Analysis of the neutron energy spectra from the sup(208)Pb (p,n) sup(208)Bi reaction at Esub(p)=200 MeV

International Nuclear Information System (INIS)

Ershov, S.N.; Fayans, S.A.; Gareev, F.A.; Pyatov, N.I.

1986-01-01

Microscopic calculation of the small-angle neutron energy spectra from the 208 Pb (p, n) 208 Bi reaction at Esub(p)=200 MeV are presented. It is shown that the distorted-wave impulse approximation and the microscopic theory of finite Fermi systems can be employed for describing the low-energy excitation region 0 <= Q <= 30 MeV with small momentum transfers. A quantitative estimate is obtained for the local charge of quasiparticles esub(q)[σtau]=0.8 that characterizes the quenching of the integral strength of spin-flip low-energy transitions and the relevant effects are discussed

General structure of democratic mass matrix of quark sector in E{sub 6} model

Energy Technology Data Exchange (ETDEWEB)

Ciftci, R., E-mail: rciftci@cern.ch [Ankara (Turkey); Çiftci, A. K., E-mail: abbas.kenan.ciftci@cern.ch [Ankara University, Ankara (Turkey)

2016-03-25

An extension of the Standard Model (SM) fermion sector, which is inspired by the E{sub 6} Grand Unified Theory (GUT) model, might be a good candidate to explain a number of unanswered questions in SM. Existence of the isosinglet quarks might explain great mass difference of bottom and top quarks. Also, democracy on mass matrix elements is a natural approach in SM. In this study, we have given general structure of Democratic Mass Matrix (DMM) of quark sector in E6 model.

SCINFUL: A Monte Carlo based computer program to determine a scintillator full energy response to neutron detection for E/sub n/ between 0. 1 and 80 MeV: Program development and comparisons of program predictions with experimental data

Energy Technology Data Exchange (ETDEWEB)

Dickens, J.K.

1988-04-01

This document provides a discussion of the development of the FORTRAN Monte Carlo program SCINFUL (for scintillator full response), a program designed to provide a calculated full response anticipated for either an NE-213 (liquid) scintillator or an NE-110 (solid) scintillator. The program may also be used to compute angle-integrated spectra of charged particles (p, d, t, /sup 3/He, and ..cap alpha..) following neutron interactions with /sup 12/C. Extensive comparisons with a variety of experimental data are given. There is generally overall good agreement (<10% differences) of results from SCINFUL calculations with measured detector responses, i.e., N(E/sub r/) vs E/sub r/ where E/sub r/ is the response pulse height, reproduce measured detector responses with an accuracy which, at least partly, depends upon how well the experimental configuration is known. For E/sub n/ < 16 MeV and for E/sub r/ > 15% of the maximum pulse height response, calculated spectra are within +-5% of experiment on the average. For E/sub n/ up to 50 MeV similar good agreement is obtained with experiment for E/sub r/ > 30% of maximum response. For E/sub n/ up to 75 MeV the calculated shape of the response agrees with measurements, but the calculations underpredicts the measured response by up to 30%. 65 refs., 64 figs., 3 tabs.

Excitation functions of inelastic and transfer channels in {sup 12} C+{sup 12} C around E{sub c.m.} = 32.5 MeV

Energy Technology Data Exchange (ETDEWEB)

Szilner, S.; Basrak, Z.; Freeman, R.M.; Haas, F.; Beck, C. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires]|[Strasbourg-1 Univ., 67 (France); Morsad, A. [Universite Hassan II, Casablanca (Morocco). Faculte des Sciences

1996-12-31

A prominent and wide resonance centered at E{sub c.m.} = 32.5 MeV has recently been found in the (0{sub 2}{sup +}, 0{sub 2}{sup +}) inelastic channel of the {sup 12}C+{sup 12}C reaction. It has been suggested that it corresponds to a 6{alpha}-particle-chain state in {sup 24}Mg. In the present work we study {sup 12}C+{sup 12}C excitation functions between center-of-mass energies of 30 and 35 MeV in steps of 250 keV for weakly populated outgoing channels. We present the inelastic channels to the states above the {alpha}-particle decay threshold, (0{sub 1}{sup +},0{sub 2}{sup +}), (0{sub 1}{sup +},3{sub 1}{sup -}), and (0{sub 1}{sup +},4{sub 1}{sup 4}), and the one- and two-nucleon transfer channels. In the inelastic and the transfer channels we observe correlated intermediate-width structures at E{sub c.m.} = 31, 32.5, and 33.5 MeV, whose widths are appreciably smaller than the width measured in the (0{sub 2}{sup +},0{sub 2}{sup +}) channel. Our E{sub c.m.} = 31, 32.5, and 33.5 MeV, whose widths are appreciably smaller than the width measured in the (0{sub 2}{sup +},0{sub 2}{sup +}) channel. Our E{sub c.m.} = 32.5 MeV angular distribution of the (0{sub 1}{sup +},0{sub 2}{sup +})channel exhibits oscillatory behavior and, unlike that of the (0{sup +}{sub 2}, 0{sup +}{sub 2}) channel, does not display enhancement around {Theta}{sub c.m.} = 90 deg. Data were collected via the kinematic coincidence technique. For data reduction we use a novel approach allowing for the extraction of results on non-binary channels. (authors). 39 refs.

Spectroscopy of the {sup 29}Si({ital p},{gamma}) reaction for {ital E}{sub {ital p}}=1.75{endash}2.51 MeV

Energy Technology Data Exchange (ETDEWEB)

Wallace, P.M.; Bilpuch, E.G.; Bybee, C.R.; Mitchell, G.E.; Moore, E.F.; Shriner, J.D.; Shriner, J.F. Jr.; Vavrina, G.A.; Westerfeldt, C.R. [Duke University, Durham, North Carolina 27708 (United States)]|[Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 North Carolina State University, Raleigh, North Carolina 27695 (United States)]|[Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 Tennessee Technological University, Cookeville, Tennessee 38505 (United States)

1996-12-01

The {sup 29}Si({ital p},{gamma}) reaction has been studied for 30 resonances in the range {ital E}{sub {ital p}}=1.75{endash}2.51 MeV. Branching ratios have been measured for 28 of these resonances. The separation energy {ital S}{sub {ital p}} for {sup 30}P has been determined to be 5594.5{plus_minus}0.5 keV. Improved spin, parity, and isospin assignments have been made to a number of the resonant states. A new level has been identified in {sup 30}P at {ital E}{sub {ital x}}=6006 keV, and its {gamma}-ray branching ratios have been measured. {copyright} {ital 1996 The American Physical Society.}

The mean photon energy anti E{sub F} at the point of measurement determines the detector-specific radiation quality correction factor k{sub Q,M} in {sup 192}Ir brachytherapy dosimetry

Energy Technology Data Exchange (ETDEWEB)

Chofor, Ndimofor; Harder, Dietrich; Selbach, Hans-Joachim; Poppe, Bjoern [University of Oldenburg and Pius-Hospital Oldenburg (Germany). Medical Radiation Physics Group

2016-11-01

The application of various radiation detectors for brachytherapy dosimetry has motivated this study of the energy dependence of radiation quality correction factor k{sub Q,M}, the quotient of the detector responses under calibration conditions at a {sup 60}Co unit and under the given non-reference conditions at the point of measurement, M, occurring in photon brachytherapy. The investigated detectors comprise TLD, radiochromic film, ESR, Si diode, plastic scintillator and diamond crystal detectors as well as ionization chambers of various sizes, whose measured response-energy relationships, taken from the literature, served as input data. Brachytherapy photon fields were Monte-Carlo simulated for an ideal isotropic {sup 192}Ir point source, a model spherical {sup 192}Ir source with steel encapsulation and a commercial HDR GammaMed Plus source. The radial source distance was varied within cylindrical water phantoms with outer radii ranging from 10 to 30 cm and heights from 20 to 60 cm. By application of this semiempirical method - originally developed for teletherapy dosimetry - it has been shown that factor k{sub Q,M} is closely correlated with a single variable, the fluence-weighted mean photon energy anti E{sub F} at the point of measurement. The radial profiles of anti E{sub F} obtained with either the commercial {sup 192}Ir source or the two simplified source variants show little variation. The observed correlations between parameters k{sub Q,M} and anti E{sub F} are represented by fitting formulae for all investigated detectors, and further variation of the detector type is foreseen. The herewith established close correlation of radiation quality correction factor k{sub Q,M} with local mean photon energy anti E{sub F} can be regarded as a simple regularity, facilitating the practical application of correction factor k{sub Q,M} for in-phantom dosimetry around {sup 192}Ir brachytherapy sources. anti E{sub F} values can be assessed by Monte Carlo simulation or

Study of the. gamma. rho. -->. n. pi. /sup +/ reaction with polarized protons and photons at E/sub. gamma. /=340 MeV

Energy Technology Data Exchange (ETDEWEB)

Get' man, V.A.; Gorbenko, V.G.; Grushin, V.F.; Derkach, A.Y.; Zhebrovskii, Y.V.; Karnaukhov, I.M.; Kolesnikov, L.Y.; Lukhanin, A.A.; Rubashkin, A.L.; Sanin, V.M.; Sorokin, P.V.; Sporov, E.A.; Telegin, Y.N.

1979-07-05

A two-fold polarization experiment of the ''beam-target'' type is carried out for the first time for the reaction ..gamma..p..-->..n..pi../sup +/ for E/sub ..gamma../ =340 MeV, and the three polarization parameters, ..sigma.., T, and P are determined simultaneously.

Raman scattering by the E{sub 2h} and A{sub 1}(LO) phonons of In{sub x}Ga{sub 1-x}N epilayers (0.25 < x < 0.75) grown by molecular beam epitaxy

Energy Technology Data Exchange (ETDEWEB)

Oliva, R.; Ibanez, J.; Cusco, R.; Artus, L. [Institut Jaume Almera, Consell Superior d' Investigacions Cientifiques (CSIC), Lluis Sole i Sabaris s.n, 08028 Barcelona, Catalonia (Spain); Kudrawiec, R. [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Serafinczuk, J. [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wroclaw (Poland); Martinez, O.; Jimenez, J. [Departamento de Fisica de la Materia Condensada, Cristalografia, y Mineralogia, Universidad de Valladolid, 47011 Valladolid (Spain); Henini, M. [Nottingham Nanotechnology and Nanoscience Centre, University of Nottingham, Nottingham NG7 2RD (United Kingdom); Boney, C.; Bensaoula, A. [Department of Physics, University of Houston, 4800 Calhoun, Houston, Texas 77004 (United States)

2012-03-15

We use Raman scattering to investigate the composition behavior of the E{sub 2h} and A{sub 1}(LO) phonons of In{sub x}Ga{sub 1-x}N and to evaluate the role of lateral compositional fluctuations and in-depth strain/composition gradients on the frequency of the A{sub 1}(LO) bands. For this purpose, we have performed visible and ultraviolet Raman measurements on a set of high-quality epilayers grown by molecular beam epitaxy with In contents over a wide composition range (0.25 < x < 0.75). While the as-measured A{sub 1}(LO) frequency values strongly deviate from the linear dispersion predicted by the modified random-element isodisplacement (MREI) model, we show that the strain-corrected A{sub 1}(LO) frequencies are qualitatively in good agreement with the expected linear dependence. In contrast, we find that the strain-corrected E{sub 2h} frequencies exhibit a bowing in relation to the linear behavior predicted by the MREI model. Such bowing should be taken into account to evaluate the composition or the strain state of InGaN material from the E{sub 2h} peak frequencies. We show that in-depth strain/composition gradients and selective resonance excitation effects have a strong impact on the frequency of the A{sub 1}(LO) mode, making very difficult the use of this mode to evaluate the strain state or the composition of InGaN material.

The multielectron character of the S 2p → 4e{sub g} shape resonance in the SF{sub 6} molecule studied via detection of soft X-ray emission and neutral high-Rydberg fragments

Energy Technology Data Exchange (ETDEWEB)

Kivimäki, A., E-mail: kivimaki@iom.cnr.it [CNR—Istituto Officina dei Materiali (IOM), Laboratorio TASC, 34149 Trieste (Italy); Coreno, M. [CNR—Istituto di Struttura della Materia (ISM), Basovizza Area Science Park, 34149 Trieste (Italy); Miotti, P.; Frassetto, F.; Poletto, L. [CNR—Istituto di Fotonica e Nanotecnologie (IFN), via Trasea 7, 35131 Padova (Italy); Stråhlman, C. [MAX IV Laboratory, Lund University, P.O. Box 118, 22100 Lund (Sweden); Simone, M. de [CNR—Istituto Officina dei Materiali (IOM), Laboratorio TASC, 34149 Trieste (Italy); Richter, R. [Elettra-Sincrotrone Trieste, Area Science Park Basovizza, 34149 Trieste (Italy)

2016-05-15

Highlights: • The soft X-ray emission spectrum of SF{sub 6} changes at the S 2p → 4e{sub g} shape resonance. • The emission band around 172 eV indicates the population of the 6a{sub 1g} orbital. • Shake-up processes accompanying S 2p ionization can explain the new emissions. • Field ionization of neutral high Rydberg (HR) fragments reveals F and S atoms. • The yield of neutral HR fragments increases at the S 2p → 4e{sub g} shape resonance. - Abstract: We have studied the nature of the S 2p → 4e{sub g} shape resonance in the SF{sub 6} molecule by performing two different experiments. Soft X-ray emission spectra measured at the 4e{sub g} shape resonance reveal features that do not originate from the S 2p{sup −1} states. One of the features can be assigned to the 6a{sub 1g} → S 2p transition. The 6a{sub 1g} orbital, which is empty in the molecular ground state, can be populated either in core–valence double excitations or in S 2p shake-up transitions. Both these channels are considered. We have also studied the fragmentation of SF{sub 6} molecule after the decay of the S 2p core-hole states by observing neutral fragments in high-Rydberg states, where an electron occupies an orbital with n ≥ 20 (n is the principal quantum number). Such neutral fragments become, in relative terms, more abundant at the S 2p → 4e{sub g} shape resonance with respect to the S 2p → 2t{sub 2g} shape resonance, which is a pure one-electron phenomenon.

Multi-step processes in the (d, t) and (d, {sup 3}He) reactions on {sup 116}Sn and {sup 208}Pb targets at E{sub d} = 200 MeV

Energy Technology Data Exchange (ETDEWEB)

Langevin-Joliot, H.; Van de Wiele, J.; Guillot, J. [Institut de Physique Nucleaire, IN2P3/CNRS, 91 - Orsay (France); Koning, A.J. [Nuclear Research and Consultancy Group NRG, NL (Netherlands)

2000-07-01

The role of multi-step processes in the reactions {sup 116}Sn(d,t), {sup 208}Pb(d,t) and {sup 116}Sn(d,{sup 3}He), previously studied at E{sub d} = 200 MeV at forward angles and for relatively low energy transfers, has been investigated. We have performed for the first time multi-step calculations taking into account systematically collective excitations in the second and higher order step inelastic transitions. A calculation code based on the Feshbach, Kerman and Koonin model has been modified to handle explicitly these collective excitations, most important in the forward angle domain. One step double differential pick-up cross sections were built from finite range distorted wave results spread in energy using known or estimated hole state characteristics. It is shown that two-step cross sections calculated using the above method compare rather well with those deduced via coupled channel calculations for the same collective excitations. The multi-step calculations performed up to 6 steps reproduce reasonably well the {sup 115}Sn, {sup 207}Pb and {sup 115}In experimental spectra measured up to E{sub x}{approx}- 40 MeV and 15 deg. The relative contributions of steps of increasing order to pick-up cross sections at E{sub d} = 200 MeV and 150 MeV are discussed. (authors)

Spectroscopy of the {sup 29}Si(p,{gamma}) reaction for E{sub p}=1.00{endash}1.75 MeV

Energy Technology Data Exchange (ETDEWEB)

Vavrina, G.A.; Bybee, C.R.; Mitchell, G.E.; Moore, E.F.; Shriner, J.D. [North Carolina State University, Raleigh, North Carolina 27695 (United States); Bilpuch, E.G.; Wallace, P.M.; Westerfeldt, C.R. [Duke University, Durham, North Carolina 27708 (United States); Shriner, J.F. , Jr. [Tennessee Technological University, Cookeville, Tennessee 38505 (United States)

1997-03-01

The {sup 29}Si(p,{gamma}) reaction has been studied in the range E{sub p}=1.00{endash}1.75 MeV. Three previously unknown states in {sup 30}P were identified, and one state previously assigned to {sup 30}P was identified as a state in {sup 14}N. Gamma-ray strengths were determined for the three new levels, and branching ratios were measured for 17 resonances. Revised J{sup {pi}};T assignments were made for nine of these states. {copyright} {ital 1997} {ital The American Physical Society}

SCINFUL: A Monte Carlo based computer program to determine a scintillator full energy response to neutron detection for E/sub n/ between 0.1 and 80 MeV: Program development and comparisons of program predictions with experimental data

International Nuclear Information System (INIS)

Dickens, J.K.

1988-04-01

This document provides a discussion of the development of the FORTRAN Monte Carlo program SCINFUL (for scintillator full response), a program designed to provide a calculated full response anticipated for either an NE-213 (liquid) scintillator or an NE-110 (solid) scintillator. The program may also be used to compute angle-integrated spectra of charged particles (p, d, t, 3 He, and α) following neutron interactions with 12 C. Extensive comparisons with a variety of experimental data are given. There is generally overall good agreement ( 15% of the maximum pulse height response, calculated spectra are within +-5% of experiment on the average. For E/sub n/ up to 50 MeV similar good agreement is obtained with experiment for E/sub r/ > 30% of maximum response. For E/sub n/ up to 75 MeV the calculated shape of the response agrees with measurements, but the calculations underpredicts the measured response by up to 30%. 65 refs., 64 figs., 3 tabs

Pair creation by very high-energy photons in gamma-ray bursts a unified picture for the energetics of GRBs

CERN Document Server

Totani, T

1999-01-01

The extreme energetics of the gamma-ray burst (GRB) 990123 have revealed that some GRBs emit quite a large amount of energy, and the total energy release from GRBs seems to change from burst to burst by a factor of 10/sup 2/-10/sup $9 3/ as E/sub gamma , iso/~10/sup 52-55/ erg, where E/sub gamma , iso/ is the observed GRB energy when the radiation is isotropic. If all GRBs are triggered by similar events, such a wide dispersion in energy release seems odd. The $9 author proposes a unified picture for the energetics of GRBs, in which all GRB events release roughly the same amount of energy E/sub iso/~10 /sup 55-56/ erg relativistic motion, with the baryon load problem almost resolved. A mild $9 dispersion in the initial Lorentz factor ( Gamma ) results in a difference of E/sub gamma , iso/ by up to a factor of m/sub p//m/sub e/~10/sup 3/. Protons work as `a hidden energy reservoir' of the total GRB energy, and E/sub gamma , $9 iso/ depends on the energy transfer efficiency from protons into electrons (or posit...

Gerbes, M5-brane anomalies and E{sub 8} gauge theory

Energy Technology Data Exchange (ETDEWEB)

Aschieri, Paolo [Dipartimento di Scienze e Tecnologie Avanzate, Universita del Piemonte Orientale and INFN, Via Bellini 25/G, 15100 Alessandria (Italy) and Max-Planck-Institut fuer Physik, Foehringer Ring 6, D-80805, Munich (Germany) and Sektion Physik, Universitaet Muenchen, Theresienstr. 37, D-80333 Munich (Germany)]. E-mail: aschieri@theorie.physik.uni-muenchen.de; Jurco, Branislav [Max-Planck-Institut fuer Physik, Foeringer Ring 6, D-80805, Munich (Germany); Sektion Physik, Universitaet Muechen, Theresienstr. 37, D-80333 Munich (Germany)

2004-10-01

Abelian gerbes and twisted bundles describe the topology of the NS 3-form gauge field strength H. We review how they have been usefully applied to study and resolve global anomalies in open string theory. Abelian 2-gerbes and twisted nonabelian gerbes describe the topology of the 4-form field strength G of M-theory. We show that twisted nonabelian gerbes are relevant in the study and resolution of global anomalies of multiple coinciding M5-branes. Global anomalies for one M5-brane have been studied by Witten and by Diaconescu, Freed and Moore. The structure and the differential geometry of twisted nonabelian gerbes (i.e. modules for 2-gerbes) is defined and studied. The nonabelian 2-form gauge potential living on multiple coinciding M5-branes arises as curving (curvature) of twisted nonabelian gerbes. The nonabelian group is in general {omega}-tildeE{sub 8}, the central extension of the E{sub 8} loop group. The twist is in general necessary to cancel global anomalies due to the non-triviality of the 11-dimensional 4-form field strength G and due to the possible torsion present in the cycles the M5-branes wrap. Our description of M5-branes global anomalies leads to the D4-branes one upon compactification of M-theory to Type IIA theory. (author)

Study of quasiexclusive neutral meson production in pN interactions at E{sub p} = 70 GeV in the deep fragmentation region

Energy Technology Data Exchange (ETDEWEB)

Golovkin, S.V.; Kozhevnikov, A.P.; Kubarovsky, V.P. [Institute for High Energy Physics (IHEP), Protvino (Russian Federation)] [and others; SPHINX Collaboration (IHEP-ITEP)

1997-11-01

Quasiexclusive neutral meson production in pN-interactions is studied in experiments with the SPHINX facility operating in a proton beam from the IHEP accelerator (E{sub p}=70 GeV). The cross sections and the parameters of the differential distributions for {pi}{sup 0}, {omega}, {eta} and K{sup 0} production in the deep fragmentation region (x{sub F}>0.79/0.86) are presented. The results show that such proton quasiexclusive reactions with baryon exchange may be promising in searches for exotic mesons. (orig.) 20 refs.

Study of deuteron photodisintegration with linearly polarized photons over the energy range E/sub el/ = 0. 4 to 0. 8 GeV

Energy Technology Data Exchange (ETDEWEB)

Agababyan, K.S.; Adamyan, F.V.; Akopyan, G.G.; Vartapetyan, G.A.; Galumyan, P.I.; Grabskii, V.O.; Karapetyan, V.V.; Karapetyan, G.V.; Kordonskii, M.S.

1985-06-01

We describe the experimental methods and the results of measurements of the asymmetry of the cross section of the eld pn reaction induced by linearly polarized photons over the energy range E/sub el/ = 0.4 to 0.8 GeV and proton angles in the c.m. system theta* = 45 to 95. Experiments were conducted on a two-arm spectrometer installation. The results obtained do not agree either with calculations within the framework of phenomenological models, or with predictions of a partial-wave analysis that includes the contribution of dibaryon resonances.

High resolution {sup 12}C({gamma},p) experiments at E{sub {gamma}} {approx_equal} 25-75 MeV

Energy Technology Data Exchange (ETDEWEB)

Ruijter, H

1995-08-01

Absolute differential cross sections for the {sup 12}C({gamma},p){sup 11}B reaction have been measured over proton detection angels ranging from 30 to 150 deg, using tagged photons of 25-75 MeV energy, for low-lying regions of residual excitation energy in {sup 11}B. Four experiments were performed at the MAX laboratory in Lund in order to provide data. Previously reported cross sections for the reaction had systematic uncertainties of a magnitude which made them agree, in spite of a large spread in absolute values. The cross sections reported, with a systematic uncertainty of 8%, remove previous ambiguities for E{sub {gamma}}=40-75 MeV. A reinterpretation of the states excited in{sup 11}B at E about 7 MeV is also presented. The data are compared with quasi-elastic (e,e`p) results in PWIA in the same recoil momentum range. It is found that the momentum distributions do not scale for the two reaction types. Furthermore, the data are compared with the results for the inverse reaction (p,{gamma}) in the centre-of-momentum system by detailed balance. The comparison with respect to missing momentum indicates an angular dependence in the ({gamma},p) reaction which is not present in the inverse (p,{gamma}) reaction. Recent results from the MAX laboratory for the ({gamma},n) reaction are compared to the ({gamma},p) results. The mirror nuclei {sup 11}C and {sup 11}B have almost identical excitation energy spectra at E{sub {gamma}}=60 MeV. It is concluded that HF-RPA calculations with essential contributions of meson exchange currents provide a qualitative description of the angular distributions obtained for the ({gamma},p) reaction. An extension of the spherical symmetric basis for the wave function is suggested for the states at E about 7 MeV in {sup 11}B. 108 refs, 83 figs.

Identification of the additional transition around the E{sub 0} critical point in photoreflectance spectra of GaInAsSb epitaxial films

Energy Technology Data Exchange (ETDEWEB)

Tirado-Mejia, L; Prias-Barragan, J J; Gomez, J F; Ariza-Calderon, H, E-mail: litirado@uniquindio.edu.c [Laboratorio de Optoelectronica, Universidad del Quindio (Colombia)

2009-05-01

We present the analysis of the photoreflectance (PR) spectra line-shape of GaInAsSb films over GaSb. The studied samples were grown by liquid phase epitaxy technique. The growth parameters such as initial temperature and contact time were the same for all samples, but the precursor solution varied slightly in the As concentration. The cooling rate was different for each sample. The PR spectra were obtained at low temperature, modulated by a 632.8 nm He-Ne laser. These spectra were fitted using the third derivative lorentzian function but, for one of the samples exhibiting an additional structure around the E{sub 0} critical point oscillation, it was also necessary to use a first derivative lorentzian function, associated to an excitonic transition. This interpretation of the new PR feature was analyzed according to X-ray diffractograms. Comparing the FWHM of the main peak in the diffractograms it was found that the sample which exhibits the excitonic transition has the best crystalline quality, and was the sample with the lower cooling rate. The excitonic energy value obtained (9.7 meV) is in agreement with the value reported in the related literature.

Bandgap measurements and the peculiar splitting of E{sub 2}{sup H} phonon modes of In{sub x}Al{sub 1-x}N nanowires grown by plasma assisted molecular beam epitaxy

Energy Technology Data Exchange (ETDEWEB)

Tangi, Malleswararao; Mishra, Pawan; Janjua, Bilal; Ng, Tien Khee; Prabaswara, Aditya; Ooi, Boon S., E-mail: boon.ooi@kaust.edu.sa [Photonics Laboratory, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900 (Saudi Arabia); Anjum, Dalaver H.; Yang, Yang [Adavanced nanofabrication Imaging and characterization, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900 (Saudi Arabia); Albadri, Abdulrahman M.; Alyamani, Ahmed Y.; El-Desouki, Munir M. [National Center for Nanotechnology, King Abdulaziz City for Science and Technology (KACST), Riyadh 11442-6086 (Saudi Arabia)

2016-07-28

The dislocation free In{sub x}Al{sub 1-x}N nanowires (NWs) are grown on Si(111) by nitrogen plasma assisted molecular beam epitaxy in the temperature regime of 490 °C–610 °C yielding In composition ranges over 0.50 ≤ x ≤ 0.17. We study the optical properties of these NWs by spectroscopic ellipsometry (SE), photoluminescence, and Raman spectroscopies since they possesses minimal strain with reduced defects comparative to the planar films. The optical bandgap measurements of In{sub x}Al{sub 1-x}N NWs are demonstrated by SE where the absorption edges of the NW samples are evaluated irrespective of substrate transparency. A systematic Stoke shift of 0.04–0.27 eV with increasing x was observed when comparing the micro-photoluminescence spectra with the Tauc plot derived from SE. The micro-Raman spectra in the NWs with x = 0.5 showed two-mode behavior for A{sub 1}(LO) phonons and single mode behavior for E{sub 2}{sup H} phonons. As for x = 0.17, i.e., high Al content, we observed a peculiar E{sub 2}{sup H} phonon mode splitting. Further, we observe composition dependent frequency shifts. The 77 to 600 K micro-Raman spectroscopy measurements show that both AlN- and InN-like modes of A{sub 1}(LO) and E{sub 2}{sup H} phonons in In{sub x}Al{sub 1-x}N NWs are redshifted with increasing temperature, similar to that of the binary III group nitride semiconductors. These studies of the optical properties of the technologically important In{sub x}Al{sub 1-x}N nanowires will path the way towards lasers and light-emitting diodes in the wavelength of the ultra-violet and visible range.

Spin and isospin characteristics of the excited states of 36Ar through the reaction 32S(α,γ)36Ar in the bombarding energy range E/sub α/ = 4 to 5 MeV

International Nuclear Information System (INIS)

Chakrabarty, D.R.; Eswaran, M.A.; Ragoowansi, N.L.

1983-01-01

The α capture reaction 32 S(α,γ) 36 Ar was studied in the bombarding energy range of E/sub α/ = 4.13 to 5.00 MeV corresponding to the excitation energy range of E/sub x/ = 10.31 to 11.08 MeV in 36 Ar. Seven resonances have been located and their resonance strengths determined. Two of the resonances decay predominantly to the ground state while the other five decay predominantly to the first excited state of 36 Ar. Angular distribution measurements of the predominant decay gamma ray have been performed and the spin and parity of all the resonances assigned. The isospin of two of the resonances have been assigned as T = 0 while T = 1 has been assigned for three others. Evidence has been obtained for the operation of the isospin selection rule for the dipole (E1 and M1) and quadrupole (E2) gamma decay

Conjugated oestrogen during the menstrual cycle measured by a direct radioimmunoassay with an antiserum prepared against oestradiol-17-glucosiduronate-(C-6)-BSA conjugate

Energy Technology Data Exchange (ETDEWEB)

Honjo, H.; Otsubo, K.; Yasuda, J.; Kitawaki, J.; Okada, H. (Department of Obstetrics and Gynaecology, Kyoto Prefectural University of Medicine, Kyoto); Ohkubo, T.; Nambara, T. (Pharmaceutical Institute, Tohoku University, Sendai, Japan)

1984-01-01

Early morning and 24 h urine samples and serum were collected daily throughout the menstrual cycle in women. Urinary oestradiol-17-glucosiduronate (E/sub 2/-17G) was measured with a direct radioimmunoassay whose antiserum has been prepared against E/sub 2/-17-G-(C-6)-bovine serum albumin conjugate and was very specific. On the average, E/sub 2/-17-G in early morning and 24 h urine samples showed a prominent peak one day before the peak of urinary LH. The time relationship between these urinary E/sub 2/-17-G and serum E/sub 2/ levels and peaks was also investigated.

Study of the reaction 35Cl(p,γγ)36Ar at the proton energy Esub(p) = 533 keV

International Nuclear Information System (INIS)

Grosswendt, B.

1972-01-01

Triple correlation experiments were carried out on the 35 Cl(p,γγ) 36 Ar reaction at the proton energy of Esub(p) = 533 keV for studies of the 9.025 MeV state in the 36 Ar nucleus. The analysis of the gamma cascades between the 36 Ar states at 9.025 MeV, 1.97 MeV and the ground state resulted in the spin assignment of J 1 =2 + for the proton capture level. Comparison of the 36 Ar level scheme with states in the isobar 36 Cl nucleus indicated that the 2 + state in 36 Ar as measured in this study may be the isobar state analogous with 2 + level at 1.949 MeV in the 36 Cl spectrum. (orig./RF) [de

Direct radioimmunoassay of urinary estrogen and pregnanediol glucuronides during the menstrual cycle

Energy Technology Data Exchange (ETDEWEB)

Stanczyk, F.Z.; Miyakawa, I.; Goebelsmann, U.

1980-06-15

Assays measuring immunoreactive estrone glucuronide (E/sub 1/G), estradiol-3-glucuronide (E/sub 2/-3G), estradiol-17..beta..-glucuronide (E/sub 2/-17G), estriol-3-glucuronide (E/sub 3/-3G), estriol-16..cap alpha..-glucuronide (E/sub 3/-16G), and pregnanediol-3..cap alpha..-glucuronide (Pd-3G) directly in diluted urine were developed and validated. These estrogen and pregnanediol glucuronide fractions were measured in aliquots of 24-hour and overnight samples of urine collected daily from seven women for one menstrual cycle. Urinary hormone excretion was correlated with daily serum estradiol (E/sub 2/), progesterone (P), and lutenizing hormonee (LH) levels. A sharp midcycle LH peak preceded by a preovulatory rise in serum E/sub 2/ and followed by luteal phase serum P levels were noted in each of the seven apparently ovulatory cycles. Twenty-four-hour and overnight urinary excretion patterns of estrogen glucuronides were similar to those of serum E/sub 2/. Of the five estrogen glucuronide fractions tested, excretion of E/sub 2/-17G exhibited the earliest and steepest ascending slope of the preovulatory estrogen surge and correlated best with serum E/sub 2/ levels. Urinary excretion of E/sub 1/-G, E/sub 2/-3G, and E/sub 3/-16G also showed an early and steep preovulatory rise and preceded that of E/sub 3/-3G, whereas urinary excretion of E/sub 3/-3G exhibited the poorest correlation with serum E/sub 2/ concentrations. The urinary excretion of Pd-3G rose parallel to serum P levels and was markedly elevated 2 to 3 days after the midcycle LH peak in both 24-hour and overnight collections of urine. These results indicate that among the urinary estrogen conjugate fractions tested, E/sub 2/-17G is the one that most suitably predicts ovulation.

Pseudo Jahn–Teller effect in distortion and restoration of planar configurations of tetra-heterocyclic 1,2-diazetes C{sub 2}N{sub 2}E{sub 4}, E = H, F, Cl, Br

Energy Technology Data Exchange (ETDEWEB)

Ilkhani, Ali R. [Institute for Theoretical Chemistry, University of Texas at Austin, Austin, TX 78712 (United States); Department of Chemistry, Yazd Branch, Islamic Azad University, Yazd (Iran, Islamic Republic of); Gorinchoy, Natalia N. [Institute of Chemistry, Academy of Sciences of Moldova, Chisinau, Republic of Moldova (Moldova, Republic of); Bersuker, Isaac B., E-mail: bersuker@cm.utexas.edu [Institute for Theoretical Chemistry, University of Texas at Austin, Austin, TX 78712 (United States); Institute of Chemistry, Academy of Sciences of Moldova, Chisinau, Republic of Moldova (Moldova, Republic of)

2015-10-16

Highlights: • The pseudo Jahn–Teller mechanism of puckering of tetracyclic 1,2-diazetes is revealed. • Vibronic constants are extracted from ab initio calculations versus PJTE equations. • Methods of restoring the planar configuration by external perturbations are suggested. - Abstract: The pseudo Jahn–Teller effect (PJTE) is employed to explain the origin of the puckered structures of tetra-heterocyclic 1,2-diazetes, C{sub 2}N{sub 2}E{sub 4}, E = H, F, Cl, Br, and to reveal the conditions of restoration of their planar configuration. The high-symmetry C{sub 2v} planar configuration of all these compounds is unstable with respect to puckering, a{sub 2}-type distortions produced by the PJT coupling between their ground {sup 1}A{sub 1} and excited {sup 1}A{sub 2} electronic states. The PJTE coupling constants are estimated by fitting ab initio calculated energy profiles to the formulas of the vibronic coupling problem (A{sub 1} + A{sub 2}) ⊗ a{sub 2}. The conditions for the restoration of the planar configurations of the C{sub 2}N{sub 2}E{sub 4} cycles were revealed: the PJTE can be quenched by removing the outer two electrons, e.g. by producing a “triple-decker sandwich” structure with two electron acceptors on both sides of the neutral cycle.

Involvement of prostaglandins F/sub 2. cap alpha. / and E/sub 1/ with rabbit endometrium

Energy Technology Data Exchange (ETDEWEB)

Orlicky, D.J.

1985-01-01

Several growth factors and hormones are thought to play a role in the growth control of endometrial cells. The authors have shown that prostaglandin F/sub 2..-->../ (PGF/sub 2..cap alpha../) is a growth factor for primary cultures of rabbit endometrium cultured in chemically-defined serum-free medium and that prostaglandin E/sub 1/ (PGE/sub 1/) antagonizes the PGF/sub 2..-->../ induction of growth. Both (/sup 3/H)PGF/sub 2..cap alpha../ and (/sup 3/H)PGE/sub 1/ bind in a time and temperature dependent, dissociable, saturable and specific manner. The binding of (/sup 3/H)PGF/sub 2..cap alpha../ and (/sup 3/H)PGE/sub 1/ can be both down and up regulated and is enzyme sensitive. PGE /sub 1/ stimulates intracellular cAMP synthesis and accumulation in a time and concentration dependent manner. PGF/sub 2..cap alpha../ probably exerts its effects through an amiloride-sensitive intermediate. Both PGF/sub 2..cap alpha../ and PGE/sub 1/ are constitutively synthesized by these primary cultures, and they have shown this synthesis to be both drug and hormone sensitive. They hypothesize that it is the ratio, rather than the absolute quantities, of PGF/sub 2..cap alpha../ and PGE/sub 1/ which is of more importance in the regulation of endometrial cell growth. Furthermore, they believe this regulation of endometrial growth plays a role in control of proliferation during the decidual response and that a derangement in the ratio of these prostaglandins may lead to either infertility or hyperplasia. The ability of these cultures to synthesize prostaglandins in a hormonally regulatable manner may be of importance in the study of dysmenorrhea and uterine cramping as caused by the myometrial contracting prostaglandin, PGF/sub 2..cap alpha../.

Tables of Shore and Fano parameters for the helium resonances 2s21S, 2p21D, and 2s 2p 1P excited in p-He collisions E/sub p/ = 33 to 150 keV

International Nuclear Information System (INIS)

Bordenave-Montesquieu, A.; Benoit-Cattin, P.; Gleizes, A.; Merchez, H.

1976-01-01

Absolute values of Shore and Fano parameters are tabulated for the helium atom 2s 2 1 S, 2p 2 1 D, and 2s 2p 1 P resonances produced by a proton beam. Observations were made on the spectra of ejected electrons. The important variation of the shape of the resonances with ejection angle is illustrated for E/sub p/ = 100 keV; the variation with proton energy is shown at 30 0

Tests of a niobium split-ring superconducting heavy ion accelerating structure

International Nuclear Information System (INIS)

Benaroya, R.; Bollinger, L.M.; Jaffey, A.H.; Khoe, T.K.; Olesen, M.C.; Scheibelhut, C.H.; Shepard, K.W.; Wesolowski, W.A.

1976-01-01

A niobium split-ring accelerating structure designed for use in the Argonne superconducting heavy-ion energy booster was successfully tested. The superconducting resonator has a resonant frequency of 97 MHz and an optimum particle velocity β = 0.11. Ultimate performance is expected to be limited by peak surface fields, which in this structure are 4.7 E/sub a/ electric and 170 E/sub a/ (Gauss) magnetic, where E/sub a/ is the effective accelerating gradient in MV/m. The rf losses in two demountable superconducting joints severely limited performance in initial tests. Following independent measurements of the rf loss properties of several types of demountable joints, one demountable joint was eliminated and the other modified. Subsequently, the resonator could be operated continuously at E/sub a/ = 3.6 MV/m (corresponding to an energy gain of 1.3 MeV per charge) with 10W rf input power. Maximum field level was limited by electron loading. The mechanical stability of the resonator under operating conditions is excellent: vibration induced eigenfrequency noise is less than 120 Hz peak to peak, and the radiation pressure induced frequency shift is Δf/f = 1.6 x 10 -6 E/sub a/ 2

Tests of a niobium split-ring superconducting heavy ion accelerating structure

Energy Technology Data Exchange (ETDEWEB)

Benaroya, R.; Bollinger, L.M.; Jaffey, A.H.; Khoe, T.K.; Olesen, M.C.; Scheibelhut, C.H.; Shepard, K.W.; Wesolowski, W.A.

1976-01-01

A niobium split-ring accelerating structure designed for use in the Argonne superconducting heavy-ion energy booster was successfully tested. The superconducting resonator has a resonant frequency of 97 MHz and an optimum particle velocity ..beta.. = 0.11. Ultimate performance is expected to be limited by peak surface fields, which in this structure are 4.7 E/sub a/ electric and 170 E/sub a/ (Gauss) magnetic, where E/sub a/ is the effective accelerating gradient in MV/m. The rf losses in two demountable superconducting joints severely limited performance in initial tests. Following independent measurements of the rf loss properties of several types of demountable joints, one demountable joint was eliminated and the other modified. Subsequently, the resonator could be operated continuously at E/sub a/ = 3.6 MV/m (corresponding to an energy gain of 1.3 MeV per charge) with 10W rf input power. Maximum field level was limited by electron loading. The mechanical stability of the resonator under operating conditions is excellent: vibration induced eigenfrequency noise is less than 120 Hz peak to peak, and the radiation pressure induced frequency shift is ..delta..f/f = 1.6 x 10/sup -6/ E/sub a//sup 2/.

Charged hadron composition of the final state in e+e- annihilation up to 1.9 GeV/c at E/sub cm/ = 29 GeV

International Nuclear Information System (INIS)

Ong, P.P.

1983-08-01

The momentum distributions of hadrons produced in e+e - collisions at a center of mass energy of 29 GeV have been measured. The data used in this analysis were collected by the High Resolution Spectrometer (HRS) at the Positron Electron Project (PEP) in the Spring of 1982. The HRS is a general purpose particle detector consisting of a 16.2 kgauss solenoidal magnet, 17 layers of tracking chambers and multiple layers of lead-scintillator shower counters. The data consist of 8,200 hadronic events, corresponding to an integrated luminosity of 19.6 pbarn -1 at E/sub cm/ = 29 GeV. Using the barrel shower counters' time-of-flight (TOF) measurements, charged particles in the momentum range 0.5 - 1.9 GeV/c are separated statistically. Measurements of differential cross sections, d sigma /dp, scaled cross sections, S*(dsigma/dXp), and charged particle fractions are presented and compared with measurements made by the TASSO and the JADE groups

Optical properties of lattice matched In{sub x}Ga{sub 1-x}P{sub 1-y}N{sub y} heteroepitaxial layers on GaP

Energy Technology Data Exchange (ETDEWEB)

Imanishi, T.; Wakahara, A.; Kim, S.M.; Yonezu, H.; Furukawa, Y. [Department of Electrical and Electron Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi, Aichi 411-8580 (Japan)

2005-04-01

Optical constants and band structure of In{sub x}Ga{sub 1-x}P{sub 1-y}N{sub y} lattice matched to GaP (100) substrate are investigated. Nitrogen concentration in the film estimated by X-ray diffraction and X-ray photoelectron spectroscopy, was 1.4%, 1.8% and 3.5%. Refractive index and transition critical points E{sub 0} ({gamma}{sub v} to {gamma}{sub c}), E{sub 1} (L{sub v} to L{sub c}) and E{sub 2} (X{sub v} to X{sub c}) are evaluated by spectroscopic ellipsometry. When N composition increases from 1.4% to 3.5%, both photoluminescence (PL) peak energy, E{sub PL}, and E{sub 0} shift to lower energy, and the energy difference {delta}E=E{sub 0}-E{sub PL} decrease from 380 meV to 110 meV. The large red-sift of E{sub PL} from the E{sub 0} suggest that the luminescence is of defect-related luminescence, and crossover point of indirect band structure estimated by the extrapolation of N-composition dependence of {delta}E is estimated to be around in In{sub 0.1}Ga{sub 0.9}P{sub 0.96}N{sub 0.04}. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Electron irradiation of near-UV GaN/InGaN light emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Lee, In-Hwan; Cho, Han-Su [Department of Materials Science and Engineering, Korea University, Seoul (Korea, Republic of); Polyakov, Alexander Y.; Smirnov, N.B.; Shchemerov, I.V.; Zinovyev, R.A.; Didenko, S.I.; Lagov, P.B. [National University of Science and Technology MISiS, Moscow (Russian Federation); Shmidt, N.M.; Shabunina, E.I. [Ioffe Physico-Technical Institute, St. Petersburg (Russian Federation); Tal' nishnih, N.A. [Submicron Heterostructures for Microelectronics Research and Engineering Center, St. Petersburg (Russian Federation); Hwang, Sung-Min [Soft-Epi, Inc., Opo-ro 240, Gwangju-si, Gyeonggi-do (Korea, Republic of); Pearton, S.J. [Department of Materials Science and Engineering, University of Florida, Gainesville, FL (United States)

2017-10-15

Irradiation with 6 MeV electrons of near-UV (peak wavelength 385-390 nm) multi-quantum-well (MQW) GaN/InGaN light emitting diodes (LEDs) causes an increase in density of deep electron traps near E{sub c} -0.8 and E{sub c} -1 eV, and correlates to a 90% decrease of electroluminescence (EL) efficiency after a fluence of 1.1 x 10{sup 16} cm{sup -2}. The likely origin of the EL efficiency decrease is this increase in concentration of the E{sub c} -0.8 eV and E{sub c} -1 eV traps. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Short gamma-ray burst formation rate from BATSE data using E{sub p} -L{sub p} correlation and the minimum gravitational-wave event rate of a coalescing compact binary

Energy Technology Data Exchange (ETDEWEB)

Yonetoku, Daisuke; Sawano, Tatsuya; Toyanago, Asuka [College of Science and Engineering, School of Mathematics and Physics, Kanazawa University, Kakuma, Kanazawa, Ishikawa 920-1192 (Japan); Nakamura, Takashi [Department of Physics, Kyoto University, Kyoto 606-8502 (Japan); Takahashi, Keitaro, E-mail: yonetoku@astro.s.kanazawa-u.ac.jp, E-mail: takashi@tap.scphys.kyoto-u.ac.jp [Faculty of Science, Kumamoto University, Kurokami, Kumamoto 860-8555 (Japan)

2014-07-01

Using 72 short gamma-ray bursts (SGRBs) with well determined spectral data observed by BATSE, we determine their redshift and luminosity by applying the E{sub p} -L{sub p} correlation for SGRBs found by Tsutsui et al. For 53 SGRBs with an observed flux brighter than 4 × 10{sup –6} erg cm{sup –2} s{sup –1}, the cumulative redshift distribution up to z = 1 agrees well with that of 22 Swift SGRBs. This suggests that the redshift determination by the E{sub p} -L{sub p} correlation for SGRBs works well. The minimum event rate at z = 0 is estimated as R{sub on−axis}{sup min}=6.3{sub −3.9}{sup +3.1}× 10{sup −10} events Mpc{sup −3} yr{sup −1}, so that the minimum beaming angle is 0.°6-7.°8 assuming a merging rate of 10{sup –7}- 4 × 10{sup –6} events Mpc{sup –3} yr{sup –1} suggested from the binary pulsar data. Interestingly, this angle is consistent with that for SGRB 130603B of ∼4°-8°. On the other hand, if we assume a beaming angle of ∼6° suggested from four SGRBs with the observed beaming angle value, then the minimum event rate including off-axis SGRBs is estimated as R{sub all}{sup min}=1.15{sub −0.66}{sup +0.56} × 10{sup −7} events Mpc{sup −3} yr{sup −1}. If SGRBs are induced by the coalescence of binary neutron stars (NSs) and/or black holes (BHs), then this event rate leads to a minimum gravitational-wave detection rate of 3.8{sub −2.2}{sup +1.8} (146{sub −83}{sup +71}) events yr{sup −1} for an NS-NS (NS-BH) binary, respectively, by a worldwide network with KAGRA, advanced-LIGO, advanced-VIRGO, and GEO.

Space-charge-limited-current diode model for amorphous silicon solar cell degradation

International Nuclear Information System (INIS)

Partain, L.D.

1987-01-01

A space-charge-limited-current (SCLI) diode model for trap controlled rectification in the dark is extended to a continuous trap distribution for p-i-n a-Si:H solar cells in the light. Light degradation, thermal annealing recovery, and 10% efficient device data are quantitatively fit with i layer, conduction electron concentrations between 1.95 (10 11 ) and 1.90 (10 12 ) cm -3 and band gap trap concentration densities between 7.66 (10 14 ) and 1.14 (10 18 ) cm -3 ev -1 for 0.2 to 0.5 eV below the conduction band edge (E/sub c/). Light exposure increased the trap density at 0.4 eV below E/sub c/ by a factor of 7. Annealing decreased the distance of the peak trap density from E/sub c/ by 0.2 eV. These results agree with trap distributions measured with field effect, DLTS, and ICTS and with theoretical models based on dangling bonds or on defect rearrangements. The model indicates that a minimum peak amplitude of 10 17 cm -3 eV -1 of trapping states is required at about 0.5 eV below E/sub c/ for high fill factors (FF) and open circuit voltages (V/sub oc/). Improved FF values of 0.76 are predicted for trap densities below 10 15 cm -3 eV -1 at 0.2 to 0.4 eV below E/sub c/. Increased V/sub oc/ values of 0.99 V are predicted for a peak trap density of 3.5 (10 17 ) cm -3 eV -1 at 0.5 eV below E/sub c/

Measurement of the cross section for forward Compton scattering by /sup 4//sub 2/ He nuclei at energies E/sub. gamma. / = 1. 8--3. 8 GeV

Energy Technology Data Exchange (ETDEWEB)

Aleksanyan, A.S.; Babayan, G.E.; Voskanyan, A.V.; Gasparyan, A.D.; Gevorkyan, S.R.; Karapetyan, S.N.; Ketikyan, A.Z.; Megrabyan, G.K.; Movsisyan, K.A.; Oganesyan, G.A.; and others

1987-04-01

The differential cross sections for Compton scattering by nuclei of /sup 4//sub 2/ He have been measured at the momentum transfers 0.02less than or equal tochemically bondtchemically bond<0.14 (GeV/c)/sup 2/ in the energy region E/sub ..gamma../ = 1.8--3.8 GeV. On the basis of the diffraction theory of multiple scattering the values of the differential cross sections at t = 0, of the slope parameters of the diffraction cone, and of the /sup 4//sub 2/ He nucleus radius have been determined. Experimental values are given for the phase of the scattering amplitude by nucleons, ..cap alpha..( f/sup 0//sub i/) = Re f/sup 0//sub i// Im f/sup 0//sub i/. On the basis of the differential cross sections at t = 0 the total photoabsorption cross section and the photon screening coefficient are determined for the /sup 4//sub 2/ He nucleus.

Irradiation induced defects containing oxygen atoms in germanium crystal as studied by deep level transient spectroscopy

International Nuclear Information System (INIS)

Fukuoka, Noboru; Kambe, Yoshiyuki; Saito, Haruo; Matsuda, Koji.

1984-05-01

Deep level transient spectroscopy was applied to the electron trapping levels which are associated with the irradiation induced lattice defects in germanium crystals. The germanium crystals used in the study were doped with oxygen, antimony or arsenic and the defects were formed by electron irradiation of 1.5MeV or 10MeV. The nature of so called ''thermal defect'' formed by heat treatment at about 670K was also studied. The trapping levels at Esub(c)-0.13eV, Esub(c)-0.25eV and Esub(c)-0.29eV were found to be associated with defects containing oxygen atoms. From the experimental results the Esub(c)-0.25eV level was attributed to the germanium A-center (interstitial oxygen atom-vacancy pair). Another defect associated with the 715cm -1 infrared absorption band was found to have a trapping level at the same position at Esub(c)-0.25eV. The Esub(c)-0.23eV and Esub(c)-0.1eV levels were revealed to be associated with thermal donors formed by heat treatment at about 670K. Additional two peaks (levels) were observed in the DLTS spectrum. The annealing behavior of the levels suggests that the thermal donors originate from not a single type but several types of defects. (author)

Photoemission study of 5f localization in UPd/sub 3-x/(Pt,Rh)/sub x/

International Nuclear Information System (INIS)

Arko, A.J.; Koelling, D.D.; Dunlap, B.D.; Mitchell, A.W.

1987-10-01

Photoemission measurements in the two systems UPd/sub 3-x/(Pt,Rh)/sub x/ show that the 5f spectra are consistent with localized 5f electrons (peak in spectral weight is below E/sub F/ for all x within the double hexagonal DO 24 phase) while at both phase transitions the 5f peaks lock in at E/sub F/ consistent with intinerancy. A satellite 5f peak representative of d-screening is observed in both localized and itinerant systems. 17 refs., 3 figs

12C(d,p) 13C reaction at Esub(d) = 30 MeV to the positive-parity states in 13C

International Nuclear Information System (INIS)

Ohnuma, H.; Hoshino, N.; Mikoshiba, O.

1985-07-01

The 12 C(d, p) 13 C reaction has been studied at Esub(d) = 30 MeV. All the known positive-parity states of 13 C below 10 MeV in excitation energy, including the 7/2 + and 9/2 + states, are observed in this reaction. The angular distributions for these positive-parity bound and unbound states are analyzed in CCBA frame work. The 13 C wave functions, which reproduce the resonant and non-resonant scattering of neutrons from 12 C, also give good accounts of the experimentally observed angular distributions and energy spectra of outgoing protons in the 12 C(d, p) 13 C reaction. In most cases the cross section magnitude and the angular distribution shape are primarily determined by the 0 + x j component, even if it is only a small fraction of the total wave function. An exception is the 7/2 + state, where the main contribution comes from the 2 + x dsub(5/2) component. The inclusion of the 4 + state in 12 C and the gsub(9/2) and gsub(7/2) neutron components in the n + 12 C system has very small effects on the low-spin states, but is indispensable for a good fit to the 7/2 + and 9/2 + angular distributions. The transitions to the negative-parity states, 1/2 1 - , 3/2 1 - , 5/2 - , 7/2 - and 1/2 3 - , are also observed experimentally, and analyzed by DWBA. (author)

Asymmetry of the cross section for the reaction. gamma. d. -->. pn induced by linearly polarized. gamma. rays in the energy region E/sub. gamma. / = 0. 4--0. 8 GeV and theta/sup c. m. //sub p/ = 45/sup 0/--95/sup 0/

Energy Technology Data Exchange (ETDEWEB)

Adamyan, F.V.; Akopyan, G.G.; Vartapetyan, G.A.; Galumyan, P.I.; Grabskii, V.O.; Karapetyan, V.V.; Karapetyan, G.V.

1984-03-10

The asymmetry (..sigma..) of the cross section for the reaction ..gamma..d..-->..pn has been measured for the energy range E/sub ..gamma../ = 0.4--0.8 GeV and for the angular interval theta/sup c.m.//sub p/ = 45/sup 0/--95/sup 0/. The results are at odds with the calculations by Ogawa et al. and by Huneke, both based on phenomenological models, and also with the predictions of the partial-wave analysis by Ideda et al., which incorporates dibaryon resonances.

Tables of Shore and Fano parameters for the helium resonances 2s/sup 2/ /sup 1/S, 2p/sup 2/ /sup 1/D, and 2s 2p /sup 1/P excited in p-He collisions E/sub p/ = 33 to 150 keV

Energy Technology Data Exchange (ETDEWEB)

Bordenave-Montesquieu, A.; Benoit-Cattin, P.; Gleizes, A.; Merchez, H.

1976-02-01

Absolute values of Shore and Fano parameters are tabulated for the helium atom 2s/sup 2/ /sup 1/S, 2p/sup 2/ /sup 1/D, and 2s 2p /sup 1/P resonances produced by a proton beam. Observations were made on the spectra of ejected electrons. The important variation of the shape of the resonances with ejection angle is illustrated for E/sub p/ = 100 keV; the variation with proton energy is shown at 30/sup 0/.

(p,p') studies of spin excitations in nuclei and of J = 4 nuclear states: Technical progress report

International Nuclear Information System (INIS)

Baker, T.

1989-01-01

During 1988 three experiments were performed. These were: 1 H, 12 C(/rvec n/,p), E/sub n/ = 860 MeV, at SATURNE, 40 Ca(/rvec p/,/rvec p/'), E/sub p/ = 581 MeV, at LAMPF, and 208 Pb(/rvec p/,/rvec p/'), E/sub p/ = 200 MeV at TRIUMF. The purpose of the (n,p) experiment, performed in June and July, was to attempt to corroborate the previously observed shifts in the ( 3 He,t) quasielastic and Δ peaks. The data are being analyzed, and since there was virtually no on-line readout during this experiment, the results are as yet unknown. 4 refs., 4 figs

Spectroscopy of virtual photons in Ar+KCl collisions at E{sub kin}=1.76 AGeV; Spektroskopie virtueller Photonen in Ar+KCl Stoessen bei E{sub kin}=1,76 AGeV

Energy Technology Data Exchange (ETDEWEB)

Jurkovic, Martin

2010-01-14

The objective of this thesis is the analysis of virtual photon emission originating from the decays of the short lived hadrons produced in Ar+KCl collisions at E{sub kin}=1.76 AGeV. The measured observables were the reconstructed e{sup +}e{sup -} pairs and their kinematic distributions. The data were recorded with the HADES spectrometer assembled at GSI Helmholtzzentrum fuer Schwerionenforschung GmbH in Darmstadt, Germany. Due to the considerably higher combinatorial background originating from the {gamma}-conversion as compared to that from light collision systems (p+p,C+C) investigated so far with HADES, a new method for identification and suppression of conversion electrons using the signal pattern in the RICH-detector was studied. An improvement of signal to background ratio (S/B) reaching 30% was achieved. For the procedure of calculating the e{sup +}/e{sup -} track efficiencies a detailed study of RICH detector signals was performed, leading to an overall improved description of ring observables in the simulation. In total, 32545pm 385 e{sup +}e{sup -} signal pairs with an opening angle {alpha}{sub ee} > 15 and 0.1 < p{sub e} < 1.1 GeV/c were identified, with 7402{+-}222 pairs in the so-called {eta} mass region (0.15 < M{sub ee} < 0.55 GeV/c{sup 2}) and 253{+-}25 for masses M{sub ee} > 0.55 GeV/c{sup 2}. A clear signal from direct {omega} decay with S/B {proportional_to}1 was identified for the first time in the SIS18 energy regime. The extraction of the {omega} yield per produced {pi}{sup 0} results in N({omega})/N({pi}{sup 0}) {approx} (4,5 {+-} 2,5(stat) {+-} 2(sys)) .10{sup -8}. The e{sup +}e{sup -} production in the {eta} mass region was compared to the expected {eta} Dalitz decay {eta}{yields}{gamma}e{sup +}e{sup -} contribution. The measured e{sup +}e{sup -} yield is higher by a factor F = 3.4{+-}0.2(stat){+-}0.6(sys){+-}0.9({eta}) as compared to the {eta} production. The excitation function of the extra e{sup +}/e{sup -} sources shows similar energy

Construction of a time-of-flight neutron spectrometer for reaction angles 000 and study of the reaction 65Cu(p,xn) 65Zn for Esub(p)=26.7 MeV

International Nuclear Information System (INIS)

Holler, Y.

1984-01-01

At the Hamburg Isochronous Cyclotron a novel time-of-flight neutron spectrometer was designed, constructed, and tested by means of a for the planned application typical nuclear reaction. The apparature was optimized for the measurement of continuous, structure-deficient neutron spectra in a wide angular range at a reproducible, as low as possible scattering neutron background. Such a facility is fitted to the strengths of the Hamburg cyclotron and allows to study questions on the precompound emission and on the inelastic projectile ( 3 He) breakup. The final test was performed with the reaction 65 Cu(p,xn) 65 Zn at Esub(p)=26.7 MeV for which already comparable data over a smaller angular range were present. In the analysis of the measurement results performed regarding the precompound effects the hybrid-exciton model calculations let recognize essential deviations at high neutron energies in the range of the extreme reaction angles. (orig./HSI) [de

Determination of electron bunch shape using transition radiation and phase-energy measurements

Energy Technology Data Exchange (ETDEWEB)

Crosson, E.R.; Berryman, K.W.; Richman, B.A. [Stanford Univ., CA (United States)] [and others

1995-12-31

We present data comparing microbunch temporal information obtained from electron beam phase-energy measurements with that obtained from transition radiation auto-correlation measurements. The data was taken to resolve some of the ambiguities in previous transition radiation results. By measuring the energy spectrum of the electron beam as a function of its phase relative to the accelerating field, phase-energy information was extracted. This data was analyzed using tomographic techniques to reconstruct the phase-space distribution assuming an electron energy dependence of E({var_phi}) = E{sub o} + E{sub acc}cos({var_phi}), where E{sub o} is the energy of an electron entering the field, E{sub acc} is the peak energy gain, and {var_phi} is the phase between the crest of the RF wave and an electron. Temporal information about the beam was obtained from the phase space distribution by taking the one dimensional projection along the time axis. We discuss the use of this technique to verify other transition radiation analysis methods.

Ar plasma induced deep levels in epitaxial n-GaAs

Energy Technology Data Exchange (ETDEWEB)

Venter, A.; Nyamhere, C.; Botha, J. R. [Department of Physics, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa); Auret, F. D.; Janse van Rensburg, P. J.; Meyer, W. E.; Coelho, S. M. M. [Department of Physics, University of the Pretoria, Lynnwood Road, Pretoria 0002 (South Africa); Kolkovsky, V. l. [Technische Universitaet, Dresden, 01062 Dresden (Germany)

2012-01-01

Ar plasma etching of n-type (Si doped) GaAs introduces several electron traps (E{sub c} - 0.04 eV, E{sub c} - 0.07 eV, E{sub c} - 0.19 eV, E{sub c} - 0.31 eV, E{sub c} - 0.53 eV, and E{sub c} - 0.61 eV). The trap, E{sub c} - 0.04 eV, labelled E1' and having a trap signature similar to irradiation induced defect E1, appears to be metastable. E{sub c} - 0.31 eV and E{sub c} - 0.61 eV are metastable too and they are similar to the M3/M4 defect configuration present in hydrogen plasma exposed n-GaAs.

Effects of the d-donor level of vanadium on the properties of Zn{sub 1−x}V{sub x}O films

Energy Technology Data Exchange (ETDEWEB)

García-Hemme, E., E-mail: eric.garcia@ucm.es [Dpto. de Física Aplicada III (Electricidad y Electrónica), Univ. Complutense de Madrid, Madrid 28040 (Spain); CEI Campus Moncloa, UCM-UPM, Madrid 28040 (Spain); Materials Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Yu, K. M. [Materials Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Department of Physics and Materials Science, City University of Hong Kong, Kowloon (Hong Kong); Wahnon, P. [CEI Campus Moncloa, UCM-UPM, Madrid 28040 (Spain); Instituto de Energía Solar and Depto TFB, E.T.S.I. Telecomunicación, Univ. Politécnica de Madrid, Ciudad Universitaria, Madrid 28040 (Spain); González-Díaz, G. [Dpto. de Física Aplicada III (Electricidad y Electrónica), Univ. Complutense de Madrid, Madrid 28040 (Spain); CEI Campus Moncloa, UCM-UPM, Madrid 28040 (Spain); Walukiewicz, W. [Materials Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)

2015-05-04

We report the effect of d-levels of vanadium atoms on the electronic band structure of ZnO. Polycrystalline layers of Zn{sub 1−x}V{sub x}O with 0 ≤ x ≤ 0.08 were synthesized using magnetron sputtering technique. Electrical measurements show that electron concentration increases with vanadium up to x = 0.04 and then decreases and films become insulating for x > 0.06. Optical characterization reveals that the absorption edge shifts to higher energy, while the photoluminescence (PL) peak shows a shift to lower energy with increasing vanadium content. This unusual optical behavior can be explained by an anticrossing interaction between the vanadium d-levels and the conduction band (CB) of ZnO. The interaction results in an upward shift of unoccupied CB (E{sub +}) and the downward shift of the fully occupied E{sub −} band derived from the vanadium d-levels. The composition dependence of optical absorption edge (E{sub +}) and PL peak (E{sub −}) can be fitted using the Band Anticrossing model with the vanadium d-level located at 0.13 eV below CB of ZnO and a coupling constant of 0.65 eV.

Detection of oxygen-related defects in GaAs by exo-electron emission spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Hulluvarad, Shiva S.; Naddaf, M.; Bhoraskar, S.V. E-mail: svb@physics.unipune.ernet.in

2001-10-01

The influence of intentional introduction of oxygen, at the surface of GaAs, on its native surface states was studied. Oxygen was made to interact with the surface of GaAs by three different means: (1) by growing native oxides, (2) exposing to oxygen plasma in an electron cyclotron resonance (ECR) plasma reactor and by (3) high energy oxygen ion irradiation. Thermally stimulated exo-electron emission (TSEE) spectroscopy was used to estimate the relative densities and energies of the surface states induced by the three different modes of introducing oxygen. Out of the two native defect levels found in GaAs by TSEE; at 325 K (0.7 eV below E{sub c}) and at 415 K (0.9 below E{sub c}); the former is seen to get broadened or split into multiple peaks in each of the methods. Multiple peaks in TSEE signify the presence of a closely spaced band of defect levels. Therefore the results exclusively point out that oxygen-related complexes contribute to the formation of a band of defects centered at 325 K in TSEE which is correlated to an energy level 0.7 eV below E{sub c} known as the EL2 defect level. The results reported in this paper thus confirm that the TSEE peak at 0.7 eV below E{sub c} is related to oxygen induced defects whereas the peak at 0.9 eV is not affected by the presence of oxygen-related species.

Dynamic Contrast Enhanced Magnetic Resonance Imaging of Diffuse Spinal Bone Marrow Infiltration in Patients with Hematological Malignancies

Energy Technology Data Exchange (ETDEWEB)

Zha, Yunfei; Li, Maojin [Renmin Hospital of Wuhan University, Wuhan (China); Yang, Jianyong [the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China)

2010-04-15

To investigate the significance of the dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) parameters of diffuse spinal bone marrow infiltration in patients with hematological malignancies. Dynamic gadolinium-enhanced MR imaging of the lumbar spine was performed in 26 patients with histologically proven diffuse bone marrow infiltration, including multiple myeloma (n = 6), acute lymphoblastic leukemia (n = 6), acute myeloid leukemia (n = 5), chronic myeloid leukemia (n = 7), and non-Hodgkin lymphoma (n = 2). Twenty subjects whose spinal MRI was normal, made up the control group. Peak enhancement percentage (E{sub max}), enhancement slope (ES), and time to peak (TTP) were determined from a time intensity curve (TIC) of lumbar vertebral bone marrow. A comparison between baseline and follow-up MR images and its histological correlation were evaluated in 10 patients. The infiltration grade of hematopoietic marrow with plasma cells was evaluated by a histological assessment of bone marrow. Differences in E{sub max}, ES, and TTP values between the control group and the patients with diffuse bone marrow infiltration were significant (t = -11.51, -9.81 and 3.91, respectively, p < 0.01). E{sub max}, ES, and TTP values were significantly different between bone marrow infiltration groups Grade 1 and Grade 2 (Z = -2.72, -2.24 and -2.89 respectively, p < 0.05). E{sub max}, ES and TTP values were not significantly different between bone marrow infiltration groups Grade 2 and Grade 3 (Z = -1.57, -1.82 and -1.58 respectively, p > 0.05). A positive correlation was found between E{sub max}, ES values and the histological grade of bone marrow infiltration (r = 0.86 and 0.84 respectively, p < 0.01). A negative correlation was found between the TTP values and bone marrow infiltration histological grade (r = -0.54, p < 0.01). A decrease in the E{sub max} and ES values was observed with increased TTP values after treatment in all of the 10 patients who responded to treatment (t

Muentz-Szasz type approximation in direct products of spaces

Energy Technology Data Exchange (ETDEWEB)

Sedletskii, A M [M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

2006-10-31

We consider the problem of completeness of the system of exponentials exp{l_brace}-{lambda}{sub n}t{r_brace}, Re {lambda}{sub n}>0, in direct products E=E{sub 1} x E{sub 2} of the spaces E{sub 1}=E{sub 1}(0,1) and E{sub 2}=E{sub 2}(1,{infinity}) of functions defined on (0,1) and (1,{infinity}), respectively. We describe rather broad classes of spaces E{sub 1} and E{sub 2} such that the well-known condition of Szasz is necessary for the completeness of the above system in E and sufficient for this completeness.

Energy distribution in semiconductors

International Nuclear Information System (INIS)

Ance, C.

1979-01-01

For various semiconductors the dispersive energy Esub(d) defined in the Wemple-Didomenico model is connected with the covalent and ionic energies Esub(h) and C. A continuous curve of ionicity against the ratio of the two energies Esub(A) and Esub(B), connected to Esub(h) and C is reported. Afromowitz's model is applied to the ternary compounds Gasub(1-x)Alsub(x)Sb using optical decomposition. From these results the average energy gap Esub(g) is given by Esub(g) = D 0 M 0 sup((IB))/(epsilon 1 (0)-1) where M 0 sup((IB)) is the interband transition contribution to the optical moment M 0 . (author)

Role of e{sub aq}{sup −}, ·OH and H· in radiolytic degradation of atrazine: A kinetic and mechanistic approach

Energy Technology Data Exchange (ETDEWEB)

Khan, Javed Ali, E-mail: javed_chemistry@yahoo.com [Radiation Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar 25120 (Pakistan); Shah, Noor S. [Radiation Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar 25120 (Pakistan); Institute of Chemical Sciences, University of Swat, Swat 19130 (Pakistan); Nawaz, Shah; Ismail, M.; Rehman, Faiza [Radiation Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar 25120 (Pakistan); Khan, Hasan M., E-mail: hmkhan@upesh.edu.pk [Radiation Chemistry Laboratory, National Centre of Excellence in Physical Chemistry, University of Peshawar, Peshawar 25120 (Pakistan)

2015-05-15

Highlights: • Atrazine was efficiently removed from aqueous solution by γ-ray irradiation. • e{sub aq}{sup −} was found to have more crucial role in removal of atrazine than ·OH. • Atrazine degradation was reduced in the presence of t-BuOH and i-PrOH. • Atrazine showed high stability at neutral pH than at very low and high pH conditions. • Potential degradation mechanism was evaluated by GC–MS analysis. - Abstract: The degradation of atrazine was investigated in aqueous solution by gamma-ray irradiation. 8.11 μM initial atrazine concentration could be completely removed in N{sub 2} saturated solution by applying 3500 Gy radiation dose at a dose rate of 296 Gy h{sup −1}. Significant removal of atrazine (i.e., 39.4%) was observed at an absorbed dose of 1184 Gy in air saturated solution and the removal efficiency was promoted to 50.5 and 65.4% in the presence of N{sub 2}O and N{sub 2} gases, respectively. The relative contributions of hydrated electron, hydroxyl radical and hydrogen radical toward atrazine degradation were determined as ratio of observed dose constant (k{sub obs}) and found to be 5: 3: 1 for k{sub eaq}{sup −}: k{sub ·OH}: k{sub H}·, respectively. The degradation efficiency of atrazine was 69.5, 55.6 and 37.3% at pH 12.1, 1.7 and 5.7, respectively. A degradation mechanism was proposed based on the identified degradation by-products by gas chromatography–mass spectrometry. Taking the relative contributions of oxidative and reductive species to atrazine degradation into account, reductive pathway proved to be a better approach for the radiolytic treatment of atrazine contaminated water.

Three-dimensional culture of sebaceous gland cells revealing the role of prostaglandin E{sub 2}-induced activation of canonical Wnt signaling

Energy Technology Data Exchange (ETDEWEB)

Yoshida, Go J., E-mail: medical21go@yahoo.co.jp; Saya, Hideyuki

2013-09-06

Highlights: •Three-dimensional culture generates “semi-vivo” sebaceous glands. •Xenograft model failed to mimic the biology of sebaceous glands in vivo. •Proinflammatory cytokine PGE{sub 2} enhances Wnt signal activity in the organoids. •PGE{sub 2} influences on the mitochondrial and lipid metabolism in the organoids. •Considering 3R agenda, “semi-vivo” sebaceous glands are useful for research. -- Abstract: Background: Prostaglandin E{sub 2} (PGE{sub 2}) is a proinflammatory mediator and activates the canonical Wnt–β-catenin signaling pathway in hematopoietic stem cells. The SZ95 cell line was established from human sebaceous gland cells and is studied as a model system for these cells. Given that 2D culture of SZ95 cells does not recapitulate the organization of sebaceous glands in situ, we developed a 3D culture system for these cells and examined the effects of PGE{sub 2} on cell morphology and function. Results: SZ95 cells maintained in 3D culture formed organoids that mimicked the organization of sebaceous glands in situ, including the establishment of a basement membrane. Organoids exposed to PGE{sub 2} were larger and adopted a more complex organization compared with control organoids. PGE{sub 2} activated the canonical Wnt signaling pathway as well as increased cell viability and proliferation, mitochondrial metabolism, and lipid synthesis in the organoids. Conclusions: Culture of SZ95 cells in 3D culture system recapitulates the structure and susceptibility to PGE{sub 2} of sebaceous glands in situ and should prove useful for studies of the response of these glands to inflammation and other environmental stressors. Our results also implicate PGE{sub 2}-induced activation of canonical Wnt signaling pathway in regulation of the morphology,proliferation, and function of “semi-vivo” sebaceous glands.

Optical spectra of Zn{sub 1-x}Be{sub x}Te mixed crystals determined by IR-VIS-UV ellipsometry and photoluminescence measurements

Energy Technology Data Exchange (ETDEWEB)

Wronkowska, A.A., E-mail: aleksandra.wronkowska@utp.edu.p [Institute of Mathematics and Physics, University of Technology and Life Sciences, S. Kaliskiego 7, PL-85796 Bydgoszcz (Poland); Arwin, H. [Department of Physics, Chemistry and Biology, Linkoeping University, SE-58183 Linkoeping (Sweden); Firszt, F.; Legowski, S. [Institute of Physics, Nicholas Copernicus University, Grudziadzka 5, PL-87100 Torun (Poland); Wronkowski, A.; Skowronski, L. [Institute of Mathematics and Physics, University of Technology and Life Sciences, S. Kaliskiego 7, PL-85796 Bydgoszcz (Poland)

2011-02-28

Spectroscopic ellipsometry in the photon energy range from 0.04 eV to 6.50 eV is used for investigation of the optical response of Zn{sub 1-x}Be{sub x}Te crystals grown by a high-pressure Bridgman method in the composition range x {<=} 0.12. Infrared spectra display absorption bands centred between 411 cm{sup -1} and 420 cm{sup -1} associated with BeTe-type optical phonon modes. The positions of the transverse-optical and longitudinal-optical phonon modes have been found by modelling the line shape of the complex dielectric functions, {epsilon}-tilde and Im(-{epsilon}-tilde{sup -1}), using a classical damped Lorentzian oscillator approach. Ellipsometric measurements in the VIS-UV range allow determination of the fundamental energy-gap (E{sub 0}) and the higher threshold energies (E{sub 1}, E{sub 1} + {Delta}{sub 1}, E{sub 2}) originating from the band edge and spin-orbit splitting critical points. We have found that the Be content x = 0.12 causes an increase of the fundamental energy gap about 0.15 eV at room temperature when compared to the E{sub 0} = 2.23 eV of ZnTe crystal at the same temperature. Photoluminescence spectra were measured in the temperature range from 30 K to room temperature. Luminescence at temperature T > 200 K is very weak. The peak positions of the exciton emission lines agree well with the E{sub 0} band-gaps derived from ellipsometric data if corrected for their temperature dependence.

Inductively coupled plasma induced deep levels in epitaxial n-GaAs

Energy Technology Data Exchange (ETDEWEB)

Auret, F.D.; Janse van Rensburg, P.J.; Meyer, W.E.; Coelho, S.M.M. [Department of Physics, University of the Pretoria, Lynnwood Road, Pretoria 0002 (South Africa); Kolkovsky, Vl. [Technische Universitaet, Dresden, 01062 Dresden (Germany); Botha, J.R.; Nyamhere, C. [Department of Physics, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa); Venter, A., E-mail: andre.venter@nmmu.ac.za [Department of Physics, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa)

2012-05-15

The electronic properties of defects introduced by low energy inductively coupled Ar plasma etching of n-type (Si doped) GaAs were investigated by deep level transient spectroscopy (DLTS) and Laplace DLTS. Several prominent electron traps (E{sub c}-0.046 eV, E{sub c}-0.186 eV, E{sub c}-0.314 eV. E{sub c}-0.528 eV and E{sub c}-0.605 eV) were detected. The metastable defect E{sub c}-0.046 eV having a trap signature similar to E1 is observed for the first time. E{sub c}-0.314 eV and E{sub c}-0.605 eV are metastable and appear to be similar to the M3 and M4 defects present in dc H-plasma exposed GaAs.

Point defect states in Sb-doped germanium

Energy Technology Data Exchange (ETDEWEB)

Patel, Neil S., E-mail: neilp@mit.edu; Monmeyran, Corentin, E-mail: comonmey@mit.edu [Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States); Agarwal, Anuradha [Microphotonics Center, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States); Kimerling, Lionel C. [Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States); Microphotonics Center, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139 (United States)

2015-10-21

Defect states in n-type Sb-doped germanium were investigated by deep-level transient spectroscopy. Cobalt-60 gamma rays were used to generate isolated vacancies and interstitials which diffuse and react with impurities in the material to form four defect states (E{sub 37}, E{sub 30}, E{sub 22}, and E{sub 21}) in the upper half of the bandgap. Irradiations at 77 K and 300 K as well as isothermal anneals were performed to characterize the relationships between the four observable defects. E{sub 37} is assigned to the Sb donor-vacancy associate (E-center) and is the only vacancy containing defect giving an estimate of 2 × 10{sup 11 }cm{sup −3} Mrad{sup −1} for the uncorrelated vacancy-interstitial pair introduction rate. The remaining three defect states are interstitial associates and transform among one another. Conversion ratios between E{sub 22}, E{sub 21}, and E{sub 30} indicate that E{sub 22} likely contains two interstitials.

The Lag-Luminosity Relation in the GRB Source-Frame: An Investigation with Swift BAT Bursts

Science.gov (United States)

Ukwatta, T. N.; Dhuga, K. S.; Stamatikos, M.; Dermer, C. D.; Sakamoto, T.; Sonbas, E.; Parke, W. C.; Maximon, L. C.; Linnemann, J. T.; Bhat, P. N.;

Recombination centers and electrical characteristics in silicon power p-i-n diodes irradiated with high energy electrons

International Nuclear Information System (INIS)

Fuochi, P.G.; Martelli, A.; Passerini, B.; Zambelli, M.

1988-01-01

Recombination centers introduced by irradiation with 12 MeV electrons in large area silicon diodes with p-i-n structure are studied with the Deep Level Transient Spectroscopy technique (DLTS). The effects of these levels on the electrical characteristics of the devices are related to their position Esub(t) in the silicon forbidden gap, their concentration and their electron capture cross section. Changes of defect configuration during an annealing process at 360 0 C have been observed and a detailed analysis of the DLTS spectra has shown a complex defect pattern. Four major recombination centers have been identified: Esub(c) - Esub(t) = 0.17 eV, Esub(c) - Esub(t) = 0.19 eV, Esub(c) -Esub(t) 0.31 eV, Esub(c) - Esub(t) = 0.39 eV, where Esub(c) is the energy corresponding to the lower limit of the conduction band. The first energy level, known as A-center, is the dominant recombination level controlling the minority carrier lifetime after room temperature irradiation. As the annealing proceeds the center at Esub(c) - Esub(t) = 0.31 eV becomes the dominant one. The complex structure of the centers has been studied and demonstrated with the aid of proper modelling implemented on a set of numerical simulation tools. In this way it has been possible to analyze more accurately the defect kinetics during annealing. The study of the defect behaviour during the annealing process has resulted in an improved application of electron irradiation as a standard production technique in the manufacturing process of high power devices. (author)

Infrared optical responses of wurtzite In{sub x}Ga{sub 1−x}N thin films with porous surface morphology

Energy Technology Data Exchange (ETDEWEB)

Yew, P., E-mail: paulinevcu@hotmail.com [Institute of Nano-Optoelectronics Research and Technology (INOR), Universiti Sains Malaysia, 11800 Minden, Penang (Malaysia); School of Physics, Universiti Sains Malaysia, 11800 Minden, Penang (Malaysia); Lee, S.C. [School of Physics, Universiti Sains Malaysia, 11800 Minden, Penang (Malaysia); Centre of Excellence for Pre-University Studies, INTI International College Penang, Laureate International University, 1-Z, Lebuh Bukit Jambul, 11900 Penang (Malaysia); Ng, S.S. [Institute of Nano-Optoelectronics Research and Technology (INOR), Universiti Sains Malaysia, 11800 Minden, Penang (Malaysia); Hassan, H. Abu [School of Physics, Universiti Sains Malaysia, 11800 Minden, Penang (Malaysia); Chen, W.L. [Department of Electronic Engineering, National Changhua University of Education, 500, Taiwan, ROC (China); Osipowicz, T.; Ren, M.Q. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 119260 (Singapore)

2016-03-31

Room temperature infrared (IR) optical responses of wurtzite indium gallium nitride (In{sub x}Ga{sub 1−x}N) in the composition range of 0.174 ≤ x ≤ 0.883 were investigated by the polarized IR reflectance spectroscopy. Analyses of the amplitudes of oscillation fringes in the non-reststrahlen region revealed that the high frequency dielectric constants of the samples were unusually smaller than the values predicted from the Clausius–Mossotti relation. This odd behavior was attributed to the porous surface morphology of the In{sub x}Ga{sub 1−x}N samples. The E{sub 1} optical phonon modes of the In{sub x}Ga{sub 1−x}N were deduced from the composition dependent reststrahlen features. The obtained values were compared to those calculated through the modified random element iso-displacement (MREI) model. The deviation between the measured data and the MREI model prediction were explained in detail from the aspects of strain, thermal expansion and anharmonic phonon-coupling. Finally, it was found that the large discrepancy of the E{sub 1}(LO) mode is mainly attributed to the effects of the longitudinal phonon–plasmon coupling. - Highlights: • Composition dependence of E{sub 1} modes of In{sub x}Ga{sub 1−x}N alloys (x = 0.174 to 0.883) • Dependence of porous morphology on infrared (IR) optical properties • Longitudinal phonon–plasmon coupling obscures determination of E{sub 1}(LO) mode.

Effect of different electrolytes on porous GaN using photo-electrochemical etching

Energy Technology Data Exchange (ETDEWEB)

Al-Heuseen, K., E-mail: kalhussen@yahoo.com [Nano-Optoelectronics Research Laboratory, School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Hashim, M.R. [Nano-Optoelectronics Research Laboratory, School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Ali, N.K. [Material Innovations and Nanoelectronics Research Group, Faculty of Electrical Engineering, Department of Electronic Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia)

2011-05-01

This article reports the properties and the behavior of GaN during the photoelectrochemical etching process using four different electrolytes. The measurements show that the porosity strongly depends on the electrolyte and highly affects the surface morphology of etched samples, which has been revealed by scanning electron microscopy (SEM) images. Peak intensity of the photoluminescence (PL) spectra of the porous GaN samples was observed to be enhanced and strongly depend on the electrolytes. Among the samples, there is a little difference in the peak position indicating that the change of porosity has little influence on the PL peak shift, while it highly affecting the peak intensity. Raman spectra of porous GaN under four different solution exhibit phonon mode E{sub 2} (high), A{sub 1} (LO), A{sub 1} (TO) and E{sub 2} (low). There was a red shift in E{sub 2} (high) in all samples, indicating a relaxation of stress in the porous GaN surface with respect to the underlying single crystalline epitaxial GaN. Raman and PL intensities were high for samples etched in H{sub 2}SO{sub 4}:H{sub 2}O{sub 2} and KOH followed by the samples etched in HF:HNO{sub 3} and in HF:C{sub 2}H{sub 5}OH.

Parallel pathways of ethoxylated alcohol biodegradation under aerobic conditions

Energy Technology Data Exchange (ETDEWEB)

Zembrzuska, Joanna, E-mail: Joanna.Zembrzuska@put.poznan.pl; Budnik, Irena, E-mail: Irena.Budnik@gmail.com; Lukaszewski, Zenon, E-mail: zenon.lukaszewski@put.poznan.pl

2016-07-01

Non-ionic surfactants (NS) are a major component of the surfactant flux discharged into surface water, and alcohol ethoxylates (AE) are the major component of this flux. Therefore, biodegradation pathways of AE deserve more thorough investigation. The aim of this work was to investigate the stages of biodegradation of homogeneous oxyethylated dodecanol C{sub 12}E{sub 9} having 9 oxyethylene subunits, under aerobic conditions. Enterobacter strain Z3 bacteria were chosen as biodegrading organisms under conditions with C{sub 12}E{sub 9} as the sole source of organic carbon. Bacterial consortia of river water were used in a parallel test as an inoculum for comparison. The LC-MS technique was used to identify the products of biodegradation. Liquid-liquid extraction with ethyl acetate was selected for the isolation of C{sub 12}E{sub 9} and metabolites from the biodegradation broth. The LC-MS/MS technique operating in the multiple reaction monitoring (MRM) mode was used for quantitative determination of C{sub 12}E{sub 9}, C{sub 12}E{sub 8}, C{sub 12}E{sub 7} and C{sub 12}E{sub 6}. Apart from the substrate, the homologues C{sub 12}E{sub 8}, C{sub 12}E{sub 7} and C{sub 12}E{sub 6}, being metabolites of C{sub 12}E{sub 9} biodegradation by shortening of the oxyethylene chain, as well as intermediate metabolites having a carboxyl end group in the oxyethylene chain (C{sub 12}E{sub 8}COOH, C{sub 12}E{sub 7}COOH, C{sub 12}E{sub 6}COOH and C{sub 12}E{sub 5}COOH), were identified. Poly(ethylene glycols) (E) having 9, 8 and 7 oxyethylene subunits were also identified, indicating parallel central fission of C{sub 12}E{sub 9} and its metabolites. Similar results were obtained with river water as inoculum. It is concluded that AE, under aerobic conditions, are biodegraded via two parallel pathways: by central fission with the formation of PEG, and by Ω-oxidation of the oxyethylene chain with the formation of carboxylated AE and subsequent shortening of the oxyethylene chain by a

Dc transport and optical measurements on the charge-density-wave compounds (K,Rb){sub 0.3}(Mo,W)O{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Al-Hadeethi, Ali Khairi Abdul-Qader

2013-04-26

The temperature dependence of the linear and the non-linear transport properties in K{sub 0.3}MoO{sub 3}, (K{sub 0.5}Rb{sub 0.5}){sub 0.3}MoO{sub 3}, and K{sub 0.3}Mo{sub 0.99}W{sub 0.01}O{sub 3} are presented. The temperature dependence of the dc resistivity of the pure sample has shown the Peierls metal-insulator phase transition at 180 K, where the transition is very sharp. The rubidium doping shifts the transition temperature to a lower temperature (170 K) and smears out the metal-insulator phase transition, i.e., the rubidium doping broadens the transition peak. Compared with the rubidium doping, the tungsten doping broadens the transition peak more and shifts the transition temperature to a lower temperature (140 K). The temperature-dependent dc resistivity curves of pure, Rb-doped, and W-doped blue bronze K{sub 0.3}MoO{sub 3} single crystals are analyzed in terms of the pseudogap just above TP and the Peierls energy gap below TP. The non-linear transport properties of pure, Rb-doped, and W-doped blue bronze K{sub 0.3}MoO{sub 3} single crystals have shown a nonlinear conductivity due to an incoherent CDW sliding, when the applied electric field exceeds the first threshold field (E{sub T}). Furthermore, above a second threshold field (E{sub T}{sup *} > E{sub T}) a coherent CDW-sliding sets in. For all studied samples, we find a monotonic increase of E{sub T} and E{sub T}{sup *} with decreasing temperature. This finding is discussed mainly in terms of the incommensurate-commensurate transition of the CDW. The coherent and incoherent CDW movements are discussed within the frame of the Fukuyama-Lee-Rice model.

A Deep Search with the Hubble Space Telescope for Late-Time Supernova Signatures in the Hosts of XRF 011030 and XRF 020427

Science.gov (United States)

Levan, Andrew; Patel, Sandeep; Kouveliotou, Chryssa; Fruchter, Andrew; Rhoads, James; Rol, Evert; Ramirez-Ruiz, Enrico; Gorosabel, Javier; Hiorth, Jens; Wijers, Ralph

2005-01-01

X-ray flashes (XRFs) are, like gamma-ray bursts (GRBs), thought to signal the collapse of massive stars in distant galaxies. Many models posit that the isotropic equivalent energies of XRFs are lower than those for GRBs, such that they are visible fiom a reduced range of distances when compared with GRBs. Here we present the results of two-epoch Hubble Space Telescope imaging of two XRFs. These images, taken approximately 45 and 200 days postburst, reveal no evidence of an associated supernova in either case. Supernovae such as SN 1998bw would have been visible out to z approximately 1.5 in each case, while fainter supernovae such as SN 2002ap would have been visible to z approximately 1. If the XRFs lie at such large distances, their energies would not fit the observed correlation between the GRB peak energy and isotropic energy release (E(sub p) proportional to E(sub iso)(sup 1/2), in which soft bursts are less energetic. We conclude that, should these XRFs reside at low redshifts (z less than 0.6), either their line of sight is heavily extinguished, they are associated with extremely faint supernovae, or, unlike GRBs, these XRFs do not have temporally coincident supernovae.

Collective ion acceleration in the system with an isolated anode

Energy Technology Data Exchange (ETDEWEB)

Bystritskii, V M; Didenko, A N; Krasik, Ya E; Lopatin, V S; Podkatov, V I [Tomskij Politekhnicheskij Inst. (USSR). Inst. Yadernoj Fiziki, Ehlektroniki i Avtomatiki

1980-01-01

Processes of collective proton acceleration in vacuum are studied in the system of an isolated anode and isolated or earthed electrodes located behind the anode on heavy-current electron accelerators ''Tonus'' and ''Vera''. The effect of external conditions and electron beam parameters on the efficiency of accelerating processes is studied. The effect of the presence of a charge pre-pulse and the number of the after-anode electrodes on the energy of accelerated energy electrons is studied. In the system with a single anode the proton yield is Nsub(p)=10sup(14) at 2Esub(e)(p)<3Esub(e). The charge pre-pulse suppression resulted in an increase of the proton energy up to (6-8)Esub(e) at the yield of 10/sup 13/. Maximum energies of protons equal to 14Esub(e) are obtained in the system with three after-anode electrodes. Possible mechanism of proton acceleration is discussed. The results are compared with those obtained elsewhere. Possibilities to increase the efficiency of this acceleration method are considered.

Model-based analysis of thromboxane B{sub 2} and prostaglandin E{sub 2} as biomarkers in the safety evaluation of naproxen

Energy Technology Data Exchange (ETDEWEB)

Sahota, Tarjinder; Sanderson, Ian; Danhof, Meindert [Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden (Netherlands); Della Pasqua, Oscar [Division of Pharmacology, Leiden Academic Centre for Drug Research, Leiden (Netherlands); Clinical Pharmacology Modelling and Simulation, GlaxoSmithKline, Uxbridge (United Kingdom)

2014-08-01

The assessment of safety in traditional toxicology protocols relies on evidence arising from observed adverse events (AEs) in animals and on establishing their correlation with different measures of drug exposure (e.g., C{sub max} and AUC). Such correlations, however, ignore the role of biomarkers, which can provide further insight into the underlying pharmacological mechanisms. Here we use naproxen as a paradigm drug to explore the feasibility of a biomarker-guided approach for the prediction of AEs in humans. A standard toxicology protocol was set up for the evaluation of effects of naproxen in rat, in which four doses were tested (7.5, 15, 40 and 80 mg/kg). In addition to sparse blood sampling for the assessment of exposure, thromboxane B{sub 2} and prostaglandin E{sub 2} were also collected in satellite groups. Nonlinear mixed effects modelling was used to evaluate the predictive performance of the approach. A one-compartmental model with first order absorption was found to best describe the pharmacokinetics of naproxen. A nonlinear relationship between dose and bioavailability was observed which leads to a less than proportional increase in naproxen concentrations with increasing doses. The pharmacodynamics of TXB{sub 2} and PGE{sub 2} was described by direct inhibition models with maximum pharmacological effects achieved at doses > 7.5 mg/kg. The predicted PKPD relationship in humans was within 10-fold of the values previously published. Moreover, our results indicate that biomarkers can be used to assess interspecies differences in PKPD and extrapolated data from animals to humans. Biomarker sampling should be used systematically in general toxicity studies. - Highlights: • Prediction of a drug's safety profile from preclinical protocols remains challenging. • Pharmacokinetic measures of safe exposure (e.g., AUC) ignore the role of biomarkers. • PKPD relationships enable the evaluation of adverse events in a mechanistic manner. • Major

Thermoluminescent relative efficiencies of TLD-100 for nitrogen ions respect of gamma radiation; Eficiencias termoluminiscentes relativas de TLD-100 para iones de nitrogeno respecto de radiacion gamma

Energy Technology Data Exchange (ETDEWEB)

Concha S, K. [UNAM, Facultad de Ciencias, 04510 Mexico D.F. (Mexico); Avila, O. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Gamboa de Buen, I. [ICN-UNAM, 04510 Mexico D.F. (Mexico); Rodriguez V, M.; Buenfil, A.E.; Ruiz T, C.; Brandan, M.E. [IFUNAM, 04510 Mexico D.F. (Mexico)

2004-07-01

The purpose of this work is to measure the thermoluminescent relative efficiency of those TLD-100 dosemeters irradiated with nitrogen ions with respect to the gamma radiation of {sup 60} Co, in function of the linear energy transfer (LET). Two energy of such nitrogen ions were selected that has the same value from LET when impacting in the dosemeters but with E{sub 1} energy (4.8 MeV) and E{sub 2} (9.95 MeV) smaller and greater respectively that the energy of the Bragg peak. (Author)

Variational theory of nuclear and neutron matter

Energy Technology Data Exchange (ETDEWEB)

Pandharipande, V.R.; Wiringa, R.B. (Illinois Univ., Urbana, IL (USA). Dept. of Physics; Argonne National Lab., IL (USA))

1989-06-01

In these lectures we will discuss attempts to solve the A = 3 to {infinity} nuclear many-body problems with the variational method. We choose the form of a variational wave function {Chi}{sub v}(1, 2{hor ellipsis}A) to describe the ground state. The {Chi}{sub v} and the ground-state energy E{sub v} are obtained by minimizing E{sub v} = {l angle}{Chi}{sub v}{vert bar}H{vert bar}{Chi}{sub v}{r angle}/{l angle}{Chi}{sub v}{vert bar}{Chi}{sub v}{r angle} with respect to variations in {Chi}{sub v}. If the form of the variational wave function is chosen properly we can expect {Chi}{sub v} {approx} {Chi}{sub 0} and E{sub v} {approx} E{sub 0} where {Chi}{sub 0} and E{sub 0} are the exact ground-state wave function and energy. In general E{sub v} {ge} E{sub 0} in variational calculations. 63 refs., 11 figs.

Admittance studies of neutron-irradiated silicon p+-n diodes

International Nuclear Information System (INIS)

Tokuda, Y.; Usami, A.

1977-01-01

Defects introduced in n-type silicon by neutron irradiation were investigated by measuring the conductance (G) and the capacitance (C) of p + -n diodes. The method of the determination of the energy level, capture cross section, and concentration for each defect from the G-T and C-T curves for various frequencies was presented. Assuming that capture cross sections are independent of temperature, the energy levels of E/sub c/-0.15 eV, E/sub c/-0.22 eV, and E/sub c/-0.39 eV were obtained. For these defects, the calculated values of the electron capture cross section were 2.6 x 10 -14 , 3.7 x 10 -15 , and 2.0 x 10 -14 cm 2 , respectively. The introduction rate of defects for E/sub c/-0.39 eV was twice that for E/sub c/-0.22 eV which was twice that for E/sub c/-0.15 eV. Comparing with other published data, the energy levels of E/sub c/-0.15 eV and E/sub c/-0.39 eV were found to be correlated with the A center and the divacancy, respectively

Differences in tibial subchondral bone structure evaluated using plain radiographs between knees with and without cartilage damage or bone marrow lesions. The Oulu knee osteoarthritis study

Energy Technology Data Exchange (ETDEWEB)

Hirvasniemi, Jukka [University of Oulu, Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, Oulu (Finland); Oulu University Hospital and University of Oulu, Medical Research Center Oulu, Oulu (Finland); Thevenot, Jerome; Podlipska, Jana [University of Oulu, Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, Oulu (Finland); University of Oulu, Infotech Oulu, Oulu (Finland); Guermazi, Ali [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); Roemer, Frank W. [Boston University School of Medicine, Quantitative Imaging Center, Department of Radiology, Boston, MA (United States); University of Erlangen-Nuremberg, Department of Radiology, Erlangen (Germany); Nieminen, Miika T.; Saarakkala, Simo [University of Oulu, Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, Oulu (Finland); Oulu University Hospital and University of Oulu, Medical Research Center Oulu, Oulu (Finland); University of Oulu, Infotech Oulu, Oulu (Finland); Oulu University Hospital, Department of Diagnostic Radiology, Oulu (Finland)

2017-11-15

To investigate whether subchondral bone structure from plain radiographs is different between subjects with and without articular cartilage damage or bone marrow lesions (BMLs). Radiography-based bone structure was assessed from 80 subjects with different stages of knee osteoarthritis using entropy of Laplacian-based image (E{sub Lap}) and local binary patterns (E{sub LBP}), homogeneity index of local angles (HI{sub Angles,mean}), and horizontal (FD{sub Hor}) and vertical fractal dimensions (FD{sub Ver}). Medial tibial articular cartilage damage and BMLs were scored using the magnetic resonance imaging osteoarthritis knee score. Level of statistical significance was set to p < 0.05. Subjects with medial tibial cartilage damage had significantly higher FD{sub Ver} and E{sub LBP} as well as lower E{sub Lap} and HI{sub Angles,mean} in the medial tibial subchondral bone region than subjects without damage. FD{sub Hor}, FD{sub Ver}, and E{sub LBP} were significantly higher, whereas E{sub Lap} and HI{sub Angles,mean} were lower in the medial trabecular bone region. Subjects with medial tibial BMLs had significantly higher FD{sub Ver} and E{sub LBP} as well as lower E{sub Lap} and HI{sub Angles,mean} in medial tibial subchondral bone. FD{sub Hor}, FD{sub Ver}, and E{sub LBP} were higher, whereas E{sub Lap} and HI{sub Angles,mean} were lower in medial trabecular bone. Our results support the use of bone structural analysis from radiographs when examining subjects with osteoarthritis or at risk of having it. (orig.)

Measurement of proton induced thick target γ-ray yields on B, N, Na, Al and Si from 2.5 to 4.1 MeV

Energy Technology Data Exchange (ETDEWEB)

Chiari, M., E-mail: chiari@fi.infn.it [INFN-Florence and Department of Physics and Astronomy, University of Florence, via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Ferraccioli, G.; Melon, B.; Nannini, A.; Perego, A.; Salvestrini, L. [INFN-Florence and Department of Physics and Astronomy, University of Florence, via G. Sansone 1, 50019 Sesto Fiorentino (Italy); Lagoyannis, A.; Preketes-Sigalas, K. [Tandem Accelerator Laboratory, Institute of Nuclear and Particle Physics, NCSR “Demokritos”, 153.10 Aghia Paraskevi, Athens (Greece)

2016-01-01

Thick target yields for proton induced γ-ray emission (PIGE) on low-Z nuclei, namely B, N, Na, Al and Si, were measured for proton energies from 2.5 to 4.1 MeV and emission angles of 0°, 45° and 90°, at the 3 MV Tandetron laboratory of INFN-LABEC in Florence. The studied reactions were: {sup 10}B(p,α′γ){sup 7}Be (E{sub γ} = 429 keV), {sup 10}B(p,p′γ){sup 10}B (E{sub γ} = 718 keV) and {sup 11}B(p,p′γ){sup 11}B (E{sub γ} = 2125 keV) for boron; {sup 14}N(p,p′γ){sup 14}N (E{sub γ} = 2313 keV) for nitrogen; {sup 23}Na(p,p′γ){sup 23}Na (E{sub γ} = 441 and 1636 keV) and {sup 23}Na(p,α′γ){sup 20}Ne (E{sub γ} = 1634 keV) for sodium; {sup 27}Al(p,p′γ){sup 27}Al (E{sub γ} = 844 and 1014 keV) and {sup 27}Al(p,α′γ){sup 24}Mg (E{sub γ} = 1369 keV) for aluminum; {sup 28}Si(p,p′γ){sup 28}Si (E{sub γ} = 1779 keV) and {sup 29}Si(p,p′γ){sup 29}Si (E{sub γ} = 1273 keV) for silicon. The PIGE thick target yields have been measured with an overall uncertainty typically better than 10%. The use of the measured thick target yield to benchmark and validate experimental cross sections available in the literature is demonstrated.

Investigation of neutron-produced defects in silicon by transconductance measurements of junction field-effect transistors

International Nuclear Information System (INIS)

Tokuda, Y.; Usami, A.

1976-01-01

Defects introduced in silicon by neutron irradiation were investigated by measuring the phase angle theta of the small-signal transconductance of the junction field-effect transistors (JFET). Measurements of theta as a function of frequency allowed the determination of the time constant for each defect. From the temperature dependence of the time constant, assuming that capture cross sections are independent of temperature, the energy levels of E/sub v/+0.19 and E/sub v/+0.35 eV in p-type silicon and E/sub c/-0.16, E/sub c/-0.19, and E/sub c/-0.44 eV in n-type silicon were obtained. For these defects, calculations gave majority-carrier capture cross-section values of 2.8 x 10 -15 and 1.1 x 10 -14 cm 2 in p-type silicon, and 3.9 x 10 -14 , 1.6 x 10 -16 , and 2.3 x 10 -14 cm 2 in n-type silicon, respectively. Comparing with other published data, it was found that the energy level of E/sub c/-0.44 eV showed the value between the previously reported energy levels of E/sub c/-0.4 and E/sub c/-0.5 eV correlated with the doubly negative charge state and singly negative charge state of the divacancy, respectively. Thus, it is believed that a total of six energy levels are introduced in silicon by neutron irradiation. The energy levels of E/sub c/-0.16 and E/sub v/+0.35 eV were found to be correlated with the A center and the divacancy, respectively

Diagnostic performance of qualitative shear-wave elastography according to different color map opacities for breast masses

Energy Technology Data Exchange (ETDEWEB)

Kim, Hana; Youk, Ji Hyun, E-mail: jhyouk@yuhs.ac; Gweon, Hye Mi; Kim, Jeong-Ah; Son, Eun Ju

2013-08-15

Purpose: To compare the diagnostic performance of qualitative shear-wave elastography (SWE) according to three different color map opacities for breast masses Materials and methods: 101 patients aged 21–77 years with 113 breast masses underwent B-mode US and SWE under three different color map opacities (50%, 19% and 100%) before biopsy or surgery. Following SWE features were reviewed: visual pattern classification (pattern 1–4), color homogeneity (E{sub homo}) and six-point color score of maximum elasticity (E{sub col}). Combined with B-mode US and SWE, the likelihood of malignancy (LOM) was also scored. The area under the curve (AUC) was obtained by ROC curve analysis to assess the diagnostic performance under each color opacity. Results: A visual color pattern, E{sub homo}, E{sub col} and LOM scoring were significantly different between benign and malignant lesions under all color opacities (P < 0.001). For 50% opacity, AUCs of visual color pattern, E{sub col}, E{sub homo} and LOM scoring were 0.902, 0.951, 0.835 and 0.975. But, for each SWE feature, there was no significant difference in the AUC among three different color opacities. For all color opacities, visual color pattern and E{sub col} showed significantly higher AUC than E{sub homo}. In addition, a combined set of B-mode US and SWE showed significantly higher AUC than SWE alone for color patterns, E{sub homo}, but no significant difference was found in E{sub col}. Conclusion: Qualitative SWE was useful to differentiate benign from malignant breast lesion under all color opacities. The difference in color map opacity did not significantly influence diagnostic performance of SWE.

Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp

Energy Technology Data Exchange (ETDEWEB)

Furman, M. A.

2010-12-11

We present simulation results of the build-up of the electron-cloud density n{sub e} in three regions of the FNAL Main Injector (MI) for a beam fill pattern made up of 5 double booster batches followed by a 6th single batch. We vary the pulse intensity in the range N{sub t} = (2-5) x 10{sup 13}, and the beam kinetic energy in the range E{sub k} = 8-120 GeV. We assume a secondary electron emission model qualitatively corresponding to TiN, except that we let the peak value of the secondary electron yield (SEY) {delta}{sub max} vary as a free parameter in a fairly broad range. Our main conclusions are: (1) At fixed N{sub t} there is a clear threshold behavior of n{sub e} as a function of {delta}{sub max} in the range {approx} 1.1-1.3. (2) At fixed {delta}{sub max}, there is a threshold behavior of n{sub e} as a function of N{sub t} provided {delta}{sub max} is sufficiently high; the threshold value of N{sub t} is a function of the characteristics of the region being simulated. (3) The dependence on E{sub k} is weak except possibly at transition energy. Most of these results were informally presented to the relevant MI personnel in April 2010.

METing SUSY on the Z peak

Energy Technology Data Exchange (ETDEWEB)

Barenboim, G.; Bernabeu, J.; Vives, O. [Universitat de Valencia, Departament de Fisica Teorica, Burjassot (Spain); Universitat de Valencia-CSIC, Parc Cientific U.V., IFIC, Paterna (Spain); Mitsou, V.A.; Romero, E. [Universitat de Valencia-CSIC, Parc Cientific U.V., IFIC, Paterna (Spain)

2016-02-15

Recently the ATLAS experiment announced a 3 σ excess at the Z-peak consisting of 29 pairs of leptons together with two or more jets, E{sub T}{sup miss} > 225 GeV and HT > 600 GeV, to be compared with 10.6 ± 3.2 expected lepton pairs in the Standard Model. No excess outside the Z-peak was observed. By trying to explain this signal with SUSY we find that only relatively light gluinos, m{sub g} or similar 400 GeV decaying predominantly to Z-boson plus a light gravitino, such that nearly every gluino produces at least one Z-boson in its decay chain, could reproduce the excess. We construct an explicit general gauge mediation model able to reproduce the observed signal overcoming all the experimental limits. Needless to say, more sophisticated models could also reproduce the signal, however, any model would have to exhibit the following features: light gluinos, or heavy particles with a strong production cross section, producing at least one Z-boson in its decay chain. The implications of our findings for the Run II at LHC with the scaling on the Z peak, as well as for the direct search of gluinos and other SUSY particles, are pointed out. (orig.)

Effect of Si substitution on structural, electronic and optical properties of YNi{sub 4}Si-type DyNi{sub 5−x}Si{sub x} (x=0, 1, 2) compounds

Energy Technology Data Exchange (ETDEWEB)

Maurya, Dinesh Kumar; Saini, Sapan Mohan, E-mail: smsaini.phy@nitrr.ac.in

2016-10-15

We employed first principle calculations for investigation of structural, electronic and optical properties of YNi{sub 4}Si-type DyNi{sub 5−x}Si{sub x} (x=0, 1, 2) compounds. These properties are studied first time on YNi{sub 4}Si-type DyNi{sub 5−x}Si{sub x} compounds. The exchange and correlation potential is treated by the Coulomb corrected local spin density approximation (LSDA+U) method for better accounting of the correlation between the 4f electrons. The optimized lattice constants and internal cell parameters are in agreement with the available data. Self consistence band structure calculations show that Ni-3d states remains in valance band and dominant below the E{sub F}, while Dy-5d and 4f states mainly contributes above Fermi Energy (E{sub F}) in DyNi{sub 5−x}Si{sub x} (x=0, 1, 2) compounds. We also find that when silicon for nickel substitution takes place (DyNi{sub 4}Si), there is a gradual hybridization of Ni-3d and Si-3p states results, nickel moments decrease rapidly in agreement with the experiment. Optical spectra shows the main absorption peak around 4 eV depends on the substituent concentration and could be due to transition from hybridized band (Ni-3d and Si-3p), below E{sub F} to free Dy-4d states. Frequency-dependent refractive index, n(ω), and the extinction coefficient, k(ω), of DyNi{sub 5−x}Si{sub x} (x=0, 1, 2) are also calculated for the radiation up to 14 eV. - Highlights: • Calculated DOS revels that Ni-3d states are dominated below Fermi level (E{sub F}). • Spin down Dy-4f states show significant contribution to DOS above E{sub F.} • Nickel moments decrease rapidly with substitution of silicon for nickel (DyNi{sub 4}Si). • Most significant peak is found around 7eV in optical conductivity. • Nickel moments decrease rapidly with substitution of silicon for nickel (DyNi{sub 4}Si). • Peak indicates the possibility of transitions from Ni-3d states to empty spin down Dy-4f states.

The effect of band Jahn-Teller distortion on the magnetoresistivity of manganites: a model study

Energy Technology Data Exchange (ETDEWEB)

Rout, G C [Condensed Matter Physics Group, P G Department of Applied Physics and Ballistics, F M University, Balasore 756 019 (India); Panda, Saswati [Trident Academy of Technology, F2/A, Chandaka Industrial Estate, Bhubaneswar 751 024 (India); Behera, S N, E-mail: gcr@iopb.res.in, E-mail: saswatip7@gmail.com [National Institute of Science and Technology, Palur Hills, Berhampur 761 008 (India)

2011-10-05

We present a model study of magnetoresistance through the interplay of magnetisation, structural distortion and external magnetic field for the manganite systems. The manganite system is described by the Hamiltonian which consists of the s-d type double exchange interaction, Heisenberg spin-spin interaction among the core electrons, and the static and dynamic band Jahn-Teller (JT) interaction in the e{sub g} band. The relaxation time of the e{sub g} electron is found from the imaginary part of the Green's function using the total Hamiltonian consisting of the interactions due to the electron and phonon. The calculated resistivity exhibits a peak in the pure JT distorted insulating phase separating the low temperature metallic ferromagnetic phase and the high temperature paramagnetic phase. The resistivity is suppressed with the increase of the external magnetic field. The e{sub g} electron band splitting and its effect on magnetoresistivity is reported here. (paper)

Assessment of the effectiveness of attenuation of leaded aprons through TLD dosimetry and Monte Carlo simulation method

Energy Technology Data Exchange (ETDEWEB)

Olaya D, H.; Diaz M, J. A.; Martinez O, S. A. [Universidad Pedagogica y Tecnologica de Colombia, Grupo de Fisica Nuclear Aplicada y Simulacion, 150003 Tunja, Boyaca (Colombia); Vega C, H. R. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas, Zac. (Mexico)

2016-10-15

Were performed experimental setups using an X-ray equipment continuous emission Pantak DXT-3000 and three types of leaded aprons with thickness of 0.25, 0.5 and 0.75 mm coated with Mylar Fiber coated Mylar on its surface. Apron was located at a distance of 2.5 m with respect focus in order to cover a radiation field size of a meter in diameter. At the beam output were added aluminum filtration in order to reproduce qualities of narrow beams N-40 (E{sub efective} = 33 keV), N-80 (E{sub efective} = 65 keV) and N-100 (E{sub efective} = 83 keV) according to the ISO standard 4037 (1-3). Each lead apron were fixed 10 TLD dosimeters over its surface, 5 dosimeters before and 5 dosimeters after with respect to X-ray beam and were calibrated for Harshaw 4500 thermoluminescent reader system order to assess the attenuation of each apron. Were performed dosimeters readings and were calculated the attenuation coefficients for each effective energy of X-ray quality. In order to confirm the method of effective energy of ISO-4037 and evaluate effectiveness of lead aprons based on energy range for each medical practice was made a Monte Carlo simulation using code GEANT-4, calculating the fluence and absorbed dose in each one of the dosimeters Monte Carlo, then coefficients of linear attenuation were calculated and compared with the experimental data and reported by the National Institute of Standards and Technology (Nist). Finally, results are consistent between theoretical calculation and experimental measures. This work will serve to make assessments for other personalized leaded protections. (Author)

Inclusive e{sup +}e{sup -} pair production in pp collisions at 2.2 GeV; Inklusive e{sup +}e{sup -}-Paarproduktion in pp-Reaktionen bei E{sub kin}=2.2 GeV

Energy Technology Data Exchange (ETDEWEB)

Sailer, B.

2007-04-10

The work presented reports on the inclusive measurement of e{sup +}e{sup -} pairs in pp collisions at a beam energy of E{sub kin}=2.2 GeV using the HADES spectrometer. HADES focuses on the measurement of e{sup +}e{sup -} pairs which are an appropriate probe to study properties of hadronic matter in heavy ion collisions. Utilizing well-known sources, the inclusive analysis of the e{sup +}e{sup -} pair signal from pp collisions gives deeper insight in the understanding of the properties of the detector system. On the other hand vaguely known additional sources are for the first time accessible with a higher precision, which is important for the later understanding of heavy ion data. One main part of the work was to perform large Monte Carlo simulations that provided a reference data sample for comparison in each analysis step. The first step was the calculation of production cross sections for resonance states which are needed as an input for the event generator Pluto++. The events produced have then been propagated through a full-scale GEANT-based detector simulation to create a realistic detector response. This work puts effort on the correct treatment of particularities of the spectrometer set-up in the pp experiment. The single particle background was strongly reduced by applying special cuts to remove electrons and positrons that originate from {gamma}-conversion. This resulted in an overall signal-to-background-ratio (S)/(B){approx}4.7, while the invariant mass region above the {pi}{sup 0} mass - which is dominated by the {eta} Dalitz decay ({eta}{yields}e{sup +}e{sup -}) still has (S)/(B){approx}2.0. The remaining pair background has been calculated using a statistical analysis of like-sign pair distributions (e{sup +}e{sup +} and e{sup -}e{sup -}) as well as uncorrelated e{sup +}e{sup -} pairs from event mixing. The remaining signal contains 2020{+-}53 e{sup +}e{sup -} pairs and is dominated by the two dalitz decays {pi}{sup 0}{yields}{gamma}e{sup +}e

Effect of acidity on the energy level of curcumin dye extracted from Curcuma longa L

Energy Technology Data Exchange (ETDEWEB)

Agustia, Yuda Virgantara, E-mail: yuda.mechanical.engineer@student.uns.ac.id; Suyitno,, E-mail: suyitno@uns.ac.id; Sutanto, Bayu, E-mail: bayu.sutanto@student.uns.ac.id [Department of Mechanical Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A, Surakarta (Indonesia); Arifin, Zainal, E-mail: zainal-a@uns.ac.id [Department of Mechanical Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A, Surakarta (Indonesia); Department of Mechanical Engineering, Brawijaya University, Malang (Indonesia)

2016-03-29

The purpose of this research is to investigate the effect of acidity on the energy level of curcumin dye. The natural dye, curcumin, was synthesized from Curcuma longa L. using a simple extraction technique. The purification of curcumin dye was conducted in a column of chromatography and its characteristics were studied. Next, the purified curcumin dye was added by benzoic acids until various acidities of 3.0, 3.5, 4.0, 4.5, and 5.0. The absorbance spectra and the functionality groups found in the dyes were detected by ultraviolet-visible spectroscopy and Fourier-transform infrared spectroscopy, respectively. Meanwhile, the energy level of the dyes, E{sub HOMO} and E{sub LUMO} was measured by cyclic voltammetry. The best energy level of curcumin dye was achieved at pH 3.5 where E{sub red} = −0.37V, E{sub LUMO} = −4.28 eV, E{sub ox} = 1.15V, E{sub HOMO} = −5.83 eV, and E{sub band} {sub gap} = 1.55 eV. Therefore, the purified curcumin dye added by benzoic acid was promising for sensitizing the dye-sensitized solar cells.

The electron as a chemical entity 201 Farday lecture

International Nuclear Information System (INIS)

Dainton, F.S.

1975-01-01

After an introductory section, the subject is covered in sections, as follows: on 'dropping' an electron into a liquid or an amorphous solid; the preparation of solvated and trapped electrons in condensed media; the physical properties of solvated or trapped electrons (the E.S.R. spectrum and cavity structure; the equivalent conductance, mobility, diffusion constant, and Stokes radius of esub(s)sup(-); the ionic atmosphere relaxation time; the thermodynamic properties of esub(s)sup(-)); spectroscopic and other evidence concerning the cavities (the effects of pressure and temperature on the spectrum; direct evidence for a range of trap sizes for esub(t)sup(-)); the trapping and solvation mechanism; the chemical reactions of esub(s)sup(-); some applications of our knowledge of esub(s)sup(-). (U.K.)

Modulation of interfacial electronic properties in PbI{sub 2} and BN van der Waals heterobilayer via external electric field

Energy Technology Data Exchange (ETDEWEB)

Ma, Yaqiang [College of Physics and Materials Science, Henan Normal University, Xinxiang 453007 (China); Zhao, Xu, E-mail: zhaoxu@htu.cn [College of Physics and Materials Science, Henan Normal University, Xinxiang 453007 (China); Niu, Mengmeng [College of Physics and Materials Science, Henan Normal University, Xinxiang 453007 (China); Dai, Xianqi, E-mail: xqdai@htu.cn [College of Physics and Materials Science, Henan Normal University, Xinxiang 453007 (China); School of Physics and Electronic Engineering, Zhengzhou Normal University, Zhengzhou, Henan 450044 (China); Li, Wei [College of Physics and Materials Science, Henan Normal University, Xinxiang 453007 (China); Wang, Xiaolong [College of Physics and Materials Science, Henan Normal University, Xinxiang 453007 (China); State Key Laboratory of Information Photonics and Optical Communication, Beijing University Posts and Telecommunications, Beijing 100876 (China); Zhao, Mingyu; Wang, Tianxing [College of Physics and Materials Science, Henan Normal University, Xinxiang 453007 (China); Tang, Yanan [School of Physics and Electronic Engineering, Zhengzhou Normal University, Zhengzhou, Henan 450044 (China)

2017-07-31

Highlights: • An atomically type-II heterobilayer which is suitable for optoelectronics and solar cell with wide bandgap was formed. • The charge redistribution is mainly on the surface and the amount of electrons depends on the strength of E{sub field}. • The bandgaps varying with E{sub field} can be divided into three ranges indicating different E{sub field}-sensitive which may possess potential in sensor. • Increasing the E{sub field} upon 0.07 V/Å, the band alignment converts from type-II to type-I heterojunction. - Abstract: The interfacial electronic properties of PbI{sub 2} and BN van der Waals (vdW) heterobilayer are explored by using density functional theory (DFT) method. An intrinsic type-II heterostructure with a wide bandgap is demonstrated. The spatial separation of the lowest energy electron-hole pairs can be actualised and make PbI{sub 2}/BN heterostructure as a good candidate for applications in optoelectronics and solar cell. A simulation of E{sub field} is actualized to modify its electronic properties. Band alignment converts from type-II to type-I heterostructure separated by a forward voltage with the value of about 0.07 V/Å. Three regions implying different E{sub field}-sensitive properties are obtained from the variations of bandgap with E{sub field}. The charge redistribution with an E{sub field} is mainly on the surface of PbI{sub 2} and BN layers as well as the amount of electrons depends on the strength of E{sub field}. In addition, the PbI{sub 2}/BN heterobilayer exhibits more outstanding optical conductivity capability. Our results could bring forward a new perspective on sensor and shed light on the design of novel nano- and optoelectronics based on the PbI{sub 2}/BN vdW heterostructure.

Standardization of androstenedione and estrone radioimmunoassay and profile of sex steroids, gonadotropins and prolactin - in patients with chronic anovulation due to inappropriate feedback (polycystic ovarian syndrome); Padronizacao do radioimunoensaio da androstenediona e da estrona e o perfil dos esteroides sexuais, gonadotrofinas e prolactina em pacientes com anovulacao cronica por retrocontrole improprio (sindrome dos ovarios policisticos)

Energy Technology Data Exchange (ETDEWEB)

Vilanova, Maria do Socorro Veras

1992-12-01

Full text. In order to evaluate the profile of the sex steroids gonadotropin and prolactin in polycystic ovarian syndrome (POS), 24 patients with POS were studied and compared with 20 normal women during the early follicular phase of the menstrual cycle. Radioimmunoassay techniques for androstenedione (A) and estrone (E{sub 1}) were standardized for the purpose of the study. Androstenedione and estrone were extracted from plasma with ethyl ether. The assays were maintained in equilibrium and the labelled hormone-antibody complex was then separated from the free hormone using dextran charcoal. The sensitivity of the method was 6.8 pg/tube for A and 3.7 pg/tube for E{sub 1}. Nonspecific binding ws 3.4 for A and 3.3 for E{sub 1}. The interessay error at the D50 level was 15.6 for A and 8.6 for E{sub 1}. Patients with POS had significantly higher basal levels of LH, A, T E{sub 1} and PRL and similar FSH and DHEA-S levels when compared with normal women. The LH/FSH ratio was significantly elevated and the A/T ratio was significantly decreased. The A/E{sub 1} and T/E{sub 2} ratios were elevated and the E{sub 1}/E{sub 2} was decreased, although the differences were not statistically significant. A positive correlation between A and E{sub 1} was observed in patients with POS. In view of the above data, it was concluded that: the quality control parameters of the radioimmunoassay for A and E{sub 1} standardized in the present study are considered satisfactory, and the assay could be used for diagnosis and research; the patients with POS have a different sex steroid and gonadotropin profile when compared normal women during the early follicular phase of the menstrual cycle

Estrogen modulation of the ethanol-evoked myocardial oxidative stress and dysfunction via DAPK3/Akt/ERK activation in male rats

Energy Technology Data Exchange (ETDEWEB)

El-Mas, Mahmoud M., E-mail: mahelm@hotmail.com; Abdel-Rahman, Abdel A., E-mail: abdelrahmana@ecu.edu

2015-09-15

Evidence suggests that male rats are protected against the hypotensive and myocardial depressant effects of ethanol compared with females. We investigated whether E{sub 2} modifies the myocardial and oxidative effects of ethanol in male rats. Conscious male rats received ethanol (0.5, 1 or 1.5 g/kg i.v.) 30-min after E{sub 2} (1 μg/kg i.v.) or its vehicle (saline), and hearts were collected at the conclusion of hemodynamic measurements for ex vivo molecular studies. Ethanol had no effect in vehicle-treated rats, but it caused dose-related reductions in LV developed pressure (LVDP), end-diastolic pressure (LVEDP), rate of rise in LV pressure (dP/dt{sub max}) and systolic (SBP) and diastolic (DBP) blood pressures in E{sub 2}-pretreated rats. These effects were associated with elevated (i) indices of reactive oxygen species (ROS), (ii) malondialdehyde (MDA) protein adducts, and (iii) phosphorylated death-associated protein kinase-3 (DAPK3), Akt, and extracellular signal-regulated kinases (ERK1/2). Enhanced myocardial anti-oxidant enzymes (heme oxygenase-1, catalase and aldehyde dehydrogenase 2) activities were also demonstrated. In conclusion, E{sub 2} promotes ethanol-evoked myocardial oxidative stress and dysfunction in male rats. The present findings highlight the risk of developing myocardial dysfunction in men who consume alcohol while receiving E{sub 2} for specific medical conditions. - Highlights: • Ethanol lowers blood pressure and causes LV dysfunction in E{sub 2}-treated rats. • E{sub 2}/ethanol aggravates cardiac oxidative state via of DAPK3/Akt/ERK activation. • E{sub 2}/ethanol causes a feedback increase in cardiac HO-1, catalase and ALDH2. • Alcohol might increase risk of myocardial dysfunction in men treated with E{sub 2}.

On the properties of nuclear matter with an excess of neutrons, of spin-up neutrons and of spin-up protons using the Skyrme interaction

International Nuclear Information System (INIS)

Hassan, M.Y.M.; Ramadan, S.

1983-11-01

The binding energy of nuclear matter with an excess of neutrons, of spin-up neutrons, and of spin-up protons (characterized by the corresponding parameters, αsub(tau)=(N-Z/A), αsub(n)=(Nup-Ndown)/A, and αsub(rho)=(Zup-Zdown)/A), contains three symmetry energies: the isospin symmetry energy Esub(tau), the spin symmetry energy Esub(σ), and spin-isospin symmetry energy Esub(σtau). General expressions for Esub(σ), Esub(tau) and Esub(σtau) are given in the case of the Skyrme interaction. These values are compared with previous results obtained by Dabrowski and Haensel (DH) with Brueckner-Gammel-Thaler, the Hamada-Johnston, and the Reid soft core nucleon-nucleon potentials. The spin, isospin and spin-isospin dependent parts of the single-particle potential in nuclear matter are also calculated using the Skyrme interaction. The spin, isospin and spin-isospin incompressibility are calculated using the Skyrme interaction. The spin-spin part of the optical model potential is estimated. The results are compared with those of Dabrowski and Haensel (DH) and Hassan and Ramadan. (author)

Above-bandgap optical properties of biaxially strained GeSn alloys grown by molecular beam epitaxy

Energy Technology Data Exchange (ETDEWEB)

Richard D’Costa, Vijay, E-mail: elevrd@nus.edu.sg; Wang, Wei; Zhou, Qian; Yeo, Yee-Chia, E-mail: eleyeoyc@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583 (Singapore); Soon Tok, Eng [Department of Physics, National University of Singapore, Singapore 117551 (Singapore)

2014-01-13

The complex dielectric function of biaxially strained Ge{sub 1−x}Sn{sub x} (0 ≤ x ≤ 0.17) alloys grown on Ge (100) has been determined by spectroscopic ellipsometry from 1.2 to 4.7 eV. The effect of substitutional Sn incorporation and the epitaxial strain on the energy transitions E{sub 1}, E{sub 1} + Δ{sub 1}, E{sub 0}′, and E{sub 2} of GeSn alloys is investigated. Our results indicate that the strained GeSn alloys show Ge-like electronic bandstructure with all the transitions shifted downward due to the alloying of Sn. The strain dependence of E{sub 1} and E{sub 1} + Δ{sub 1} transitions is explained using the deformation potential theory, and values of −5.4 ± 0.4 eV and 3.8 ± 0.5 eV are obtained for the hydrostatic and shear deformation potentials, respectively.

The role of Al, Ba, and Cd dopant elements in tailoring the properties of c-axis oriented ZnO thin films

Energy Technology Data Exchange (ETDEWEB)

Ali, Dilawar [Department of Physics GC University, Lahore 54000 (Pakistan); Center for Advanced Studies in Physics, GC University Lahore, Lahore 54000 (Pakistan); Butt, M.Z., E-mail: mzakriabutt@gmail.com [Center for Advanced Studies in Physics, GC University Lahore, Lahore 54000 (Pakistan); Arif, Bilal [Department of Physics, Faculty of Arts and Sciences, Firat University, 23169 Elazig (Turkey); Al-Ghamdi, Ahmed A. [Department of Physics, Faculty of Sciences, King Abdul Aziz University, Jeddah (Saudi Arabia); Yakuphanoglu, Fahrettin [Department of Physics, Faculty of Arts and Sciences, Firat University, 23169 Elazig (Turkey); Department of Physics, Faculty of Sciences, King Abdul Aziz University, Jeddah (Saudi Arabia)

2017-02-01

Highly c-axis oriented un-doped ZnO and Al-, Ba-, and Cd-doped ZnO thin films were successfully deposited on glass substrate employing sol-gel spin coating method. XRD analysis showed that all thin films possess hexagonal wurtzite structure with preferred orientation along c-axis. Field emission scanning electron microscope (FESEM) was used to study the morphology of thin films. The morphology consists of spherical and non-spherical shape grains. EDX analysis confirms the presence of O, Zn, Al, Ba, and Cd in the relevant thin films. The optical properties of thin films were studied using UV–Vis spectrometer. All thin films possess more than 85% optical transmittance in the visible region. Blue shift in optical band gap E{sub g} has been observed on doping with Al, whereas doping with Ba and Cd resulted in red shift of E{sub g}. Urbach energy E{sub u} of all doped ZnO thin films was found to have excellent correlation with their band gap energy E{sub g}. Moreover, E{sub g} increases while E{sub u} decreases on the increase in crystallite size D. Optical parameters E{sub g} and E{sub u} as well as structural parameters lattice strain and stacking fault probability also show excellent correlation with the B-factor or the mean-square amplitude of atomic vibrations of the dopant elements. Electrical conductivity measurement of the thin films was carried out using two-point probe method. The electrical conductivity was found to increase with the increase in crystallite orientation along c-axis.

Statistical theory of L-H transition in tokamaks

Energy Technology Data Exchange (ETDEWEB)

Itoh, S.-I. [Kyushu Univ., Research Institute for Applied Mechanics, Kasuga, Fukuoka (Japan); Itoh, K.; Toda, S. [National Inst. for Fusion Science, Toki, Gifu (Japan)

2003-01-01

A statistical model for the bifurcation of the radial electric field E{sub r} is developed in view of describing L-H transitions of tokamak plasmas. Noise in micro fluctuations is shown to lead to random changes of E{sub r}, if a deterministic approach allows for more than one solution. The probability density function for and the ensemble average of E{sub r} are obtained. The L-to-H and the H-to-L transition probabilities are calculated, and the effective phase limit is derived. Due to the suppression of turbulence by shear in E{sub r}, the limit deviates from Maxwell's rule. The ensemble average of heat flux as well as that of E{sub r} do not show a hysteresis in contrast to the deterministic model. Experimental condition for observing the hysteresis is also addressed. (author)

Relationship between the dielectric and mechanical properties and the ratio of epoxy resin to hardener of the hybrid thermosetting polymers

Energy Technology Data Exchange (ETDEWEB)

Dias Filho, Newton Luiz; Aquino, Hermes Adolfo de; Pires, Geovanna; Caetano, Laercio [UNESP, Ilha Solteira, SP (Brazil). Faculdade de Engenharia. Dept. de Fisica e Quimica]. E-mail: nldias@dfq.feis.unesp.br

2006-05-15

The relationship between the dielectric properties (dielectric constant, {epsilon}'', and loss factor, {epsilon}''; activation energy, E{sub a}) and the ratio of epoxy resin (OG) to hardener of the epoxy resin thermosetting polymers was investigated. The amplitude of the {epsilon}'' peak decreases with increasing OG content until about 73 wt.% and slightly increases at higher OG content. The temperature of the position of the {epsilon}'' peak increases with the increasing of OG content, reaching maximum values for compositions in the range of 67 and 73 wt.%, and then it decreases sharply at higher OG content. The activation energy obtained from dielectric relaxation increased with increasing wt.% OG up to around 70 wt.%. Further increase in concentration of OG up to 83 wt.% reduced E{sub a}. The curves of tensile modulus and fracture (author)

Effect of deep levels of radiation-induced defects in silicon γ-irradiated Al-V-n-Si structures characteristics

International Nuclear Information System (INIS)

Buzaneva, E.V.; Vdovichenko, A.D.; Kuznetsov, G.V.; Muntyan, Yu.G.

1985-01-01

The effect of high energy γ-quanta irradiation on the mechanism of current transmission in Al-V-N-Si structures employed in Schottky barrier instruments has been investigated. Before irradiation the structures have been annealed in the nitrogen atmosphere at T=500 deg C. The samples have been γ-irradiated on the side of the metall film at T=20 deg C. The irradiation spectrum is continuous, maximum γ-quanta energy 50 MeV, medium one is 20 MeV. The integral flux of γ-quanta, PHIsub(γ) varied from 10 7 to 10 13 quantum/cm -2 . The volt-ampere and volt-farad characteristics have been measred. It is shown that variation of the main electrophysical characteristics of the Al-V-nSi structures upon γ-irradiation is due to deep levels of radiation defects arising in silicon with the energetic position Esub(c)-E=0.38-0.4 eV and Esub(v)+Esub(2)=0.23-0.25 → β, where Esub(c), Esub(v) are energies for the conduction band bottom and the valence band ceiling. In the 77-293 K temperature range the determining range the determining effect on current mission mechanism in irradiated structures is exerted by resonance electron tunnelling with participation of a level with the Esub(c)-Esub(1)=0.38-0.4 eV

Adsorption of carbon dioxide (CO{sub 2}) at S functionalized boron nitride (BN) and aluminum nitride (AlN) nanotubes (9, 0): A quantum chemical investigation

Energy Technology Data Exchange (ETDEWEB)

Najafi, Meysam, E-mail: meysamnajafi2016@yahoo.com

2016-10-30

Highlights: • AlN-NT has higher potential to CO{sub 2} adsorption in comparison to BN-NT. • S functionalization of studied nanotubes improve the CO{sub 2} adsorption ability of them. • E{sub ad} is suitable scale to propose the novel toxic gas sensor based on nanostructured. • E{sub ad} and E{sub HLG} of studied nanotubes have linear dependences. - Abstract: We employed density functional theory to characterize CO{sub 2} adsorption on BNNT and AlNNT surfaces. The effects of S functionalization on the adsorption of CO{sub 2} gas on BNNT and AlNNT surfaces were investigated. Results reveal that adsorptions of CO{sub 2} on studied nanotubes were exothermic and experimentally possible from the energetic viewpoint. Results show that, E{sub ad} values of CO{sub 2} on AlNNT surface were more negative than corresponding values of BNNT. Results reveal that, S functionalization of studied nanotubes causes an increase in the absolute values of E{sub ad} of CO{sub 2} on surface of studied nanotubes. These results show that, there are good linearity dependencies between E{sub ad} and orbital energy values of studied nanotubes. Therefore we can conclude the E{sub ad} and orbital energy values are highly sensitive to the adsorption process which these may be used for the selection the suitable nanotubes with enhanced CO{sub 2} adsorption potential.

Study of evaporation in Ca + Ca deep inelastic scattering at 400 MeV and setting-up of a conversational computing system

International Nuclear Information System (INIS)

Ameaume, A.

1979-01-01

The study of inelastic interactions between symmetrical systems allows to calculate the number of nucleons lost by evaporation; the identity of initial particles, within a two body hypothesis in the exit channel, implies a symmetry in the charge and mass distributions of the final nuclei. But these nuclei, in the first stage of reaction, are emitted with some excitation energy, so the observer detects only the cold products resulting from their de-excitation by evaporation. The study of the 40 Ca + 40 Ca system at 400 MeV, with an E-ΔE telescope in the laboratory angular range from 10 to 80 degrees, allowed to calculate number of lost charges ΔZ = 20 - Z versus the total excitation energy Esub(x) of the intermediate system, where Z represents the mean value of charge distributions at fixed Esub(x) and center-of-mass angle theta. The setting-up of an iterative calculation of ΔZ = f(Esub(x)) was necessary to access the Esub(x) energies before evaporation. The results are consistent with an energy thermalization hypothesis and show a linear increase of ΔZ versus Esub(x), independently of theta. The charge loss rate for one excited calcium varies from 1.6 for Esub(x) = 50 MeV to 4.8 for Esub(x) = 150 MeV [fr

Evolution of the optical properties of chromium doped calcium tetraborate glass under high pressure

Energy Technology Data Exchange (ETDEWEB)

Lesniewski, Tadeusz, E-mail: tadeusz.lesniewski@phdstud.ug.edu.pl [Institute of Experimental Physics, University of Gdansk, Wita Stwosza 57, 80-952 Gdansk (Poland); Barzowska, Justyna; Mahlik, Sebastian; Behrendt, Mirosław [Institute of Experimental Physics, University of Gdansk, Wita Stwosza 57, 80-952 Gdansk (Poland); Padlyak, Bohdan V. [Sector of Spectroscopy, Vlokh Institute of Physical Optics, Dragomanov St. 23, 79-005 Lviv (Ukraine); Division of Spectroscopy of Functional Materials, Institute of Physics, University of Zielona Gora, Szafrana St. 4a, 65-516 Zielona Gora (Poland); Grinberg, Marek, E-mail: fizmgr@ug.edu.pl [Institute of Experimental Physics, University of Gdansk, Wita Stwosza 57, 80-952 Gdansk (Poland)

2016-09-15

In this contribution, we present luminescence properties of calcium tetraborate glass (CaB{sub 4}O{sub 7}) activated with Cr{sup 3+} ions. Excitation spectra, steady state and time resolved luminescence spectra at temperatures between 10 K and 300 K and at high hydrostatic pressure up to 120 kbar were measured. The excitation spectrum consists of two broad bands peaking at 420 nm and 580 nm related to transitions from the {sup 4}A{sub 2g} ground state to {sup 4}T{sub 1g} and {sup 4}T{sub 2g} excited states, respectively. Ambient pressure luminescence spectrum consists of two bands peaking at 690 nm and 850 nm. First band is related to the spin forbidden {sup 2}E{sub g}→{sup 4}A{sub 2g} transition, whereas the second broad band is related to the spin allowed {sup 4}T{sub 2g}→{sup 4}A{sub 2g} transition. Widths of both bands are significantly greater than natural due to inhomogeneous broadening. The ratio between intensities of these bands is strongly temperature and pressure dependent. At pressure below 50 kbar relative contribution of the {sup 2}E{sub g}→{sup 4}A{sub 2g} luminescence decreases with increasing temperature and increases when pressure is applied. For pressure higher than 50 kbar only the emission related to the {sup 2}E{sub g}→{sup 4}A{sub 2g} transition is observed. Analysis of luminescence lineshape and kinetics allowed to estimate the width of the crystal field distribution and show that even at ambient pressure most of the Cr{sup 3+} ions occupy high field sites with energy of the {sup 4}T{sub 2g} higher than the energy of the {sup 2}E{sub g} state.

Study of the giant multipole resonances, especially the isoscalar giant E2 resonance in 208Pb by inelastic electron scattering with medium and high energy resolution

International Nuclear Information System (INIS)

Kuehner, E.G.F.

1982-01-01

In the nucleus 208 Pb giant multipole resonances were looked for by inelastic electron scattering up to excitation energies of Esub(x) = 35 MeV. Twelve spectra were taken up at incident energies of Esub(o) = 45-65 MeV under scattering angles from upsilon = 93 0 to 165 0 . The cross sections extracted from this were analyzed by means of DWBA calculations using RPA amplitudes from a model with separable residual interaction. Basing on this analysis for the first time it could be shown that the maximum in the electron scattering cross section at Esub(x) approx.= 14 MeV can be consistently described as a superposition of the Jsup(π) = 1 - , ΔT = 1 with a Jsup(π) = 0 + , ΔT = 0 giant resonance. Furthermore the spectra under backward scattering angles indicate the existence of a magnetic excitation at Esub(x) approx.= 15 MeV which is interpreted as Jsup(π) = 3 + giant resonance. Besides under forwards angles a further weak excitation appears at Esub(x) approx.= 14.6 MeV which is very well compatible with Jsup(π) = 2 + . At Esub(x) = 17.5 MeV a Jsup(π) = 3 - resonance was found which recently is also observed in (α,α') scattering experiments and therefore gets a ΔT = 0 assignment. A further resonance at Esub(x) approx.= 21 MeV has also Jsup(π) = 3 - character but has partly to be assigned to a Jsup(π) = 1 - , ΔT = 0 excitation. At Esub(x) = 23.8 MeV a Jsup(π) = 2 + excitation was found which gels because of model predictions a ΔT = 1 assignment. (orig./HSI) [de

Coulomb correlation effects in YBaCuO system

Energy Technology Data Exchange (ETDEWEB)

Costa-Quintana, J; Lopez-Aguilar, F; Munoz, J S; Sanchez, A [Dept. de Fisica, Grupo de Electromagnetismo, Univ. Autonoma de Barcelona (Spain); Balle, S [Dept. de Fisica, Univ. de les Illes Balears, Palma de Mallorca (Spain)

1989-12-01

In this work, we apply a mean field potential deduced from the multiband Hubbard hamiltonian in order to obtain the lower and upper strongly correlated bands. We have obtained the total and partial density of states for U{sub d} = 0 and U{sub d} = 4 eV. The results show that the density of states calculated with U{sub d} = 4 eV at E{sub F} is lesser than that obtained with U{sub d} = 0. A small peak above E{sub F} arising from the strong correlated bands appears in the dDOS calculated with U{sub d} = 4 eV and this is in agreement with the experimental data. (orig.).

Research on the reactions {sup 9}Be ({sup 3}He, 3 {alpha}) and {sup 10}B (d, 3 {alpha}); Contribution a l'etude experimentale des reactions {sup 9}Be ({sup 3}He, 3 {alpha}) et {sup 10}B (d, 3 {alpha})

Energy Technology Data Exchange (ETDEWEB)

Thouvenin, P [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1967-06-15

For studying these reactions, the detection of the final particles emitted in coincidence in the directions {theta}{sub 1} and {theta}{sub 2}, together with the bi-parametric analysis of the corresponding pulses are used. This method enables us to obtain the orthogonal Dalitz diagrams (E{sub 1}, E{sub 2}). An examination of the spectra obtained shows that the sequential mechanism appears to predominate. The contribution of the purely statistical process is less than 15 per cent of the total spectrum. In the case of {sup 10}B (d, 3 {alpha}), for E{sub d} = 1.5 MeV, 2,66 MeV and 3 MeV, the width of the peak of the first particles emitted, with respect to {sup 8}Be excitations close to 11 MeV, is found to be equal to 2.6 {+-} 0.6 MeV, much less than the width of the 2. excited state observed by {alpha} - {alpha} scattering. The coincidence spectra and the free spectra give an excitation energy of E{sub x} = 2.68 {+-} 0.07 MeV for the first excited state of {sup 8}Be. Some remarks are made concerning the anomalies observed for E{sub d} = 5 MeV and 9 MeV. The excited levels of {sup 8}Be at 13.91 MeV and 7.56 MeV which have been described in the past are not observed. (author) [French] La detection de deux des particules finales emises en cofncidence dans les directions {theta}{sub 1} et {theta}{sub 2}, et l'analyse biparametrique des impulsions correspondantes sont utilisees pour etudier ces reactions. Cette methode nous permet d'obtenir des diagrammes de Dalitz orthogonaux (E{sub 1}, E{sub 2}). L'examen des spectres obtenus montre que le mecanisme sequentiel semble predominant. La contribution du processus purement statistique est inferieure a 15 pour cent du spectre total. Dans le cas de {sup 10}B (d, 3 {alpha}), pour E{sub d} = 1,5 MeV, 2,66 MeV et 3 MeV, la largeur du pic des premieres particules emises relatives a des excitations de {sup 8}Be voisines de 11 MeV, est trouvee egale a 2,6 {+-} 0,6 MeV, tres inferieure a la largeur du 2. etat excite observee a l

Research on the reactions {sup 9}Be ({sup 3}He, 3 {alpha}) and {sup 10}B (d, 3 {alpha}); Contribution a l'etude experimentale des reactions {sup 9}Be ({sup 3}He, 3 {alpha}) et {sup 10}B (d, 3 {alpha})

Energy Technology Data Exchange (ETDEWEB)

Thouvenin, P. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

1967-06-15

For studying these reactions, the detection of the final particles emitted in coincidence in the directions {theta}{sub 1} and {theta}{sub 2}, together with the bi-parametric analysis of the corresponding pulses are used. This method enables us to obtain the orthogonal Dalitz diagrams (E{sub 1}, E{sub 2}). An examination of the spectra obtained shows that the sequential mechanism appears to predominate. The contribution of the purely statistical process is less than 15 per cent of the total spectrum. In the case of {sup 10}B (d, 3 {alpha}), for E{sub d} = 1.5 MeV, 2,66 MeV and 3 MeV, the width of the peak of the first particles emitted, with respect to {sup 8}Be excitations close to 11 MeV, is found to be equal to 2.6 {+-} 0.6 MeV, much less than the width of the 2. excited state observed by {alpha} - {alpha} scattering. The coincidence spectra and the free spectra give an excitation energy of E{sub x} = 2.68 {+-} 0.07 MeV for the first excited state of {sup 8}Be. Some remarks are made concerning the anomalies observed for E{sub d} = 5 MeV and 9 MeV. The excited levels of {sup 8}Be at 13.91 MeV and 7.56 MeV which have been described in the past are not observed. (author) [French] La detection de deux des particules finales emises en cofncidence dans les directions {theta}{sub 1} et {theta}{sub 2}, et l'analyse biparametrique des impulsions correspondantes sont utilisees pour etudier ces reactions. Cette methode nous permet d'obtenir des diagrammes de Dalitz orthogonaux (E{sub 1}, E{sub 2}). L'examen des spectres obtenus montre que le mecanisme sequentiel semble predominant. La contribution du processus purement statistique est inferieure a 15 pour cent du spectre total. Dans le cas de {sup 10}B (d, 3 {alpha}), pour E{sub d} = 1,5 MeV, 2,66 MeV et 3 MeV, la largeur du pic des premieres particules emises relatives a des excitations de {sup 8}Be voisines de 11 MeV, est trouvee egale a 2,6 {+-} 0,6 MeV, tres inferieure a la largeur du 2. etat excite

Effects of partitioned enthalpy of mixing on glass-forming ability

Energy Technology Data Exchange (ETDEWEB)

Song, Wen-Xiong; Zhao, Shi-Jin, E-mail: shijin.zhao@shu.edu.cn [Institute of Materials Science, Shanghai University, Shanghai 200072 (China)

2015-04-14

We explore the inherent reason at atomic level for the glass-forming ability of alloys by molecular simulation, in which the effect of partitioned enthalpy of mixing is studied. Based on Morse potential, we divide the enthalpy of mixing into three parts: the chemical part (Δ E{sub nn}), strain part (Δ E{sub strain}), and non-bond part (Δ E{sub nnn}). We find that a large negative Δ E{sub nn} value represents strong AB chemical bonding in AB alloy and is the driving force to form a local ordered structure, meanwhile the transformed local ordered structure needs to satisfy the condition (Δ E{sub nn}/2 + Δ E{sub strain}) < 0 to be stabilized. Understanding the chemical and strain parts of enthalpy of mixing is helpful to design a new metallic glass with a good glass forming ability. Moreover, two types of metallic glasses (i.e., “strain dominant” and “chemical dominant”) are classified according to the relative importance between chemical effect and strain effect, which enriches our knowledge of the forming mechanism of metallic glass. Finally, a soft sphere model is established, different from the common hard sphere model.

Electrical characterization of deep levels in n-type GaAs after hydrogen plasma treatment

Energy Technology Data Exchange (ETDEWEB)

Nyamhere, C., E-mail: s210239522@live.nmmu.ac.z [Department of Physics, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa); Botha, J.R.; Venter, A. [Department of Physics, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa)

2011-05-15

Deep level transient spectroscopy (DLTS) and Laplace-DLTS (L-DLTS) have been used to investigate defects in an n-type GaAs before and after exposure to a dc hydrogen plasma (hydrogenation). DLTS revealed the presence of three prominent electron traps in the material in the temperature range 20-300 K. However, L-DLTS with its higher resolution enabled the splitting of two narrowly spaced emission rates. Consequently four electron traps at, E{sub C}-0.33 eV, E{sub C}-0.36 eV, E{sub C}-0.38 eV and E{sub C}-0.56 eV were observed in the control sample. Following hydrogenation, all these traps were passivated with a new complex (presumably the M3), emerging at E{sub C}-0.58 eV. Isochronal annealing of the passivated material between 50 and 300 {sup o}C, revealed the emergence of a secondary defect, not previously observed, at E{sub C}-0.37 eV. Finally, the effect of hydrogen passivation is completely reversed upon annealing at 300 {sup o}C, as all the defects originally observed in the reference sample were recovered.

Resonance broadening in an intense light field

International Nuclear Information System (INIS)

Andreev, S.P.; Lisitsa, V.S.

1977-01-01

Collisions of identical atoms in a strong resonance radiation field E 0 cosωt, for which the atomic oscillation period is comparable to the collision time of the atoms, are considered. The problem is treated in terms of the simplest two-level atomic model. The problem of light absorption in such collisions is reduced to the problem of inelastic transitions in a three-level compound system of two atoms and an electromagnetic field. Corresponding probabilities and inelastic scattering integral cross sections for transitions between energy levels in such a system are calculated for two extreme cases- the impact (rapid collisions) and the static one (slow collisions). In the general case the cross sections depend nonlinearly on Esub(0). For small Esub(0) as compared to a certain critical Esub(0)* the results are similar to those of the well-known linear theory of resonance broadening. For Esub(0)>>Esub(0)* the absorption in the line wing is found to decrease (with increase of Esub(0)-the medium becomes more ''transparent''). The kinetics of light absorption in the medium of identical atoms with constant absorption capacity is analysed

Investigation of human teeth with respect to the photon interaction, energy absorption and buildup factor

Energy Technology Data Exchange (ETDEWEB)

Kurudirek, Murat, E-mail: mkurudirek@gmail.co [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey); Topcuoglu, Sinan [Faculty of Dentistry, Department of Endodontic, Ataturk University, 25240 Erzurum (Turkey)

2011-05-15

The effective atomic numbers and electron densities of human teeth have been calculated for total photon interaction (Z{sub PI{sub e{sub f{sub f}}}},Ne{sub PI{sub e{sub f{sub f}}}}) and photon energy absorption (Z{sub PEA{sub e{sub f{sub f}}}},Z{sub RW{sub e{sub f{sub f}}}}Ne{sub PEA{sub e{sub f{sub f}}}}) in the energy region 1 keV-20 MeV. Besides, the energy absorption (EABF) and exposure (EBF) buildup factors have been calculated for these samples by using the geometric progression fitting approximation in the energy region 0.015-15 MeV up to 40 mfp (mean free path). Wherever possible the results were compared with experiment. Effective atomic numbers (Z{sub PI{sub e{sub f{sub f}}}}) of human teeth were calculated using different methods. Discrepancies were noted in Z{sub PI{sub e{sub f{sub f}}}} between the direct and interpolation methods in the low and high energy regions where absorption processes dominate while good agreement was observed in intermediate energy region where Compton scattering dominates. Significant variations up to 22% were observed between Z{sub PI{sub e{sub f{sub f}}}} and Z{sub PEA{sub e{sub f{sub f}}}} in the energy region 30-150 keV which is the used energy range in dental cone beam computed tomography (CBCT) X-ray machines. The Z{sub eff} values of human teeth were found to relatively vary within 1% if different laser treatments are applied. In this variation, the Er:YAG laser treated samples were found to be less effected than Nd:YAG laser treated ones when compared with control group. Relative differences between EABF and EBF were found to be significantly high in the energy region 60 keV-1 MeV even though they have similar variations with respect to the different parameters viz. photon energy, penetration depth.

Observation of jets in high transverse energy events at the CERN proton antiproton collider

International Nuclear Information System (INIS)

Arnison, G.; Astbury, A.; Grayer, G.; Haynes, W.J.; Nandi, A.K.; Roberts, C.; Scott, W.; Shah, T.P.; Bowcock, T.J.V.; Eisenhandler, E.; Gibson, W.R.; Honma, A.; Kalmus, P.I.P.; Keeler, R.; Salvi, G.; Thompson, G.; Cochet, C.; DeBeer, M.; Denegri, D.; Givernaud, A.; Laugier, J.P.; Leveque, A.; Locci, E.; Loret, M.; Malosse, J.J.; Rich, J.; Sass, J.; Saudraix, J.; Savoy-Navarro, A.; Spiro, M.; Dobrzynski, L.; Fontaine, G.; Geer, S.; Ghesquiere, C.; Giraud-Heraud, Y.; Kryn, D.; Mendiburu, J.P.; Orkin-Lecourtois, A.; Sajot, G.; Vrana, J.; Bacci, C.; Bernabei, R.; Ceradini, F.; Corden, M.; Dallman, D.; D'Angelo, S.; Dowell, J.D.; Edwards, M.; Eggert, K.; Ellis, N.; Erhard, P.; Faissner, H.; Frey, R.; Fruehwirth, R.; Garvey, J.; Giboni, K.L.; Gutierrez, P.; Hansl-Kozanecka, T.; Hodges, C.; Hoffmann, D.; Homer, R.J.; Karimaeki, V.; Kenyon, I.; Kernan, A.; Kinnunen, R.; Kozanecki, W.; Lehmann, H.; Leuchs, R.; McMahon, T.; Moricca, M.; Paoluzi, L.; Pimia, M.; Radermacher, E.; Ransdell, J.; Reithler, H.; Salvini, G.; Strauss, J.; Sumorok, K.; Szoncso, F.; Tscheslog, E.; Tuominiemi, J.; Wahl, H.D.; Watkins, P.; Wilson, J.

1983-01-01

With a segmented total absorption calorimeter of large acceptance, we have measured the total transverse energy spectrum for panti p collisions at ssup(1/2)=540 GeV up to μEsub(T)=130 GeV in the pseudo-rapidity range vertical strokeetavertical stroke 40 GeV, the fraction of events with two jets increases with μEsub(T); this event structure is dominant for μEsub(T)> 100 GeV. We measure the inclusive jet cross section up to Esub(T)(jet)=60 GeV and the two-jet mass distribution up to 120 GeV/c 2 . The measured cross sections are compatible with the predictions of hard scattering models based on QCD. (orig.)

What energy does gravity unite with grand unified theories in the early universe

International Nuclear Information System (INIS)

Sivaram, C.

1987-01-01

Unification of gravity with GUTs is usually expected at the Planck energy E/sub PI/ ∼ 10 19 GeV. However, the vastly different values of the two couplings at E/sub PI/ (α/sub GUT/ E/sub PI/ with a single dimensionless coupling constant (α/sub U/ << 1) and described by a scale-invariant action quadratic in the Weyl curvature (with Yang-Mills fields). Breaking of scale invariance at E/sub PI/ then separates the interactions into gravity, now described by a Hilbert action with a dimensional G and GUTs with a dimensionless α/sub GUT/ and YM action. Problems with Klein-Kaluza unification of gravity with GUTs are also discussed in this context

Efficient mass-selective three-photon ionization of zirconium atoms

Science.gov (United States)

Page, Ralph H.

1994-01-01

In an AVLIS process, .sup.91 Zr is selectively removed from natural zirconium by a three-step photoionization wherein Zr atoms are irradiated by a laser beam having a wavelength .lambda..sub.1, selectively raising .sup.91 Zr atoms to an odd-parity E.sub.1 energy level in the range of 16000-19000 cm.sup.-1, are irradiated by a laser beam having a wavelength .lambda..sub.2 to raise the atoms from an E.sub.l level to an even-parity E.sub.2 energy level in the range of 35000-37000 cm.sup.-1 and are irradiated by a laser beam having a wavelength .lambda..sub.3 to cause a resonant transition of atoms from an E.sub.2 level to an autoionizing level above 53506 cm.sup.-1. .lambda..sub.3 wavelengths of 5607, 6511 or 5756 .ANG. will excite a zirconium atom from an E.sub.2 energy state of 36344 cm.sup.-1 to an autoionizing level; a .lambda..sub.3 wavelength of 5666 .ANG. will cause an autoionizing transition from an E.sub.2 level of 36068 cm.sup.-1 ; and a .lambda. .sub.3 wavelength of 5662 .ANG. will cause an ionizing resonance of an atom at an E.sub.2 level of 35904 cm.sup.-1.

Dislocation-related trap levels in nitride-based light emitting diodes

Energy Technology Data Exchange (ETDEWEB)

Venturi, Giulia; Castaldini, Antonio; Cavallini, Anna [Department of Physics and Astronomy, University of Bologna, Viale Berti Pichat 6/2, Bologna 40127 (Italy); Meneghini, Matteo; Zanoni, Enrico [Department of Information Engineering, University of Padova, via Gradenigo 6/B, Padova 35131 (Italy); Zhu, Dandan; Humphreys, Colin [Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS (United Kingdom)

2014-05-26

Deep level transient spectroscopy was performed on InGaN/GaN multiple quantum well light emitting diodes (LEDs) in order to determine the effect of the dislocation density on the deep intragap electronic levels. The LEDs were grown by metalorganic vapor phase epitaxy on GaN templates with a high dislocation density of 8 × 10{sup 9} cm{sup −2} and a low dislocation density of 3 × 10{sup 8} cm{sup −2}. Three trapping levels for electrons were revealed, named A, A1, and B, with energies E{sub A} ≈ 0.04 eV, E{sub A1} ≈ 0.13 eV, and E{sub B} ≈ 0.54 eV, respectively. The trapping level A has a much higher concentration in the LEDs grown on the template with a high density of dislocations. The logarithmic dependence of the peak amplitude on the bias pulse width for traps A and A1 identifies the defects responsible for these traps as associated with linearly arranged defects. We conclude that traps A and A1 are dislocation-related intragap energy levels.

Physics of ep collisions in the TeV energy range

International Nuclear Information System (INIS)

Altarelli, G.; Mele, B.; Rueckl, R.

1984-01-01

We study the physics of electron-proton collisions in the range of centre-of-mass energies between √s approx.= 0.3 TeV (HERA) and √s approx.= (1-2) TeV. The latter energies would be achieved if the electron or positron beam of LEP [Esub(e) approx.= (50-100) GeV] is made to collide with the proton beam of LHC [Esub(p) approx.= (5-10) TeV]. (orig.)

Some constructions on total labelling of m triangles

Energy Technology Data Exchange (ETDEWEB)

Voon, Chen Huey, E-mail: chenhv@utar.edu.my; Hui, Liew How, E-mail: liewhh@utar.edu.my; How, Yim Kheng, E-mail: tidusyimhome@hotmail.com [Department of Mathematical and Actuarial Sciences, Lee Kong Chian Faculty of Engineering and Science, Universiti Tunku Abdul Rahman, Jalan Sungai Long, Bandar Sungai Long, Cheras 43000 Kajang, Selangor (Malaysia)

2016-06-02

Let mK{sub 3} = (V{sub m}, E{sub m}) be a finite disconnected graph consisting of m disjoint triangles K{sub 3}, where V{sub m} is the set of vertices, E{sub m} is the set of edges and both V{sub m} and E{sub m} are of the same size 3m. A total labelling of mK{sub 3} is a function f which maps the elements in V{sub m} and E{sub m} to positive integer values, i.e. f : V{sub m} ∪ E{sub m} → {1, 2, 3,···}. Let c be a positive integer. A triangle is said have a c-Erdősian triangle labelling if it is a total labelling f : V{sub m} ∪ E{sub m} → {c, c + 1, ···, c + 6m − 1} such that f (x) + f (y) = f (xy) for any x, y ∈ V{sub m} and an edge xy ∈ E{sub m} joining them. In order to find all the c-Erdősian triangle labelling, a straightforward is to use the exhaustive search. However, the exhaustive search is only able to find c-Erdősian triangle labelling for m ≤ 5 due to combinatorial explosion. By studying the constant sum of vertex labels, we propose a strong permutation approach, which allows us to generate a certain classes of c-Erdősian triangle labelling up until m = 8.

Study on Corrosion Inhibition Efficiency of Stem Alkaloid Extract of Different Varieties of Holy Basil on Aluminium in HCl Solution

Energy Technology Data Exchange (ETDEWEB)

Kumpawat, Nutan; Chaturvedi, Alok; Upadhyay, R. K. [Synthetic and Surface Science Laboratory, Ajmer (India)

2012-08-15

Corrosion inhibition efficiencies of holy basil on Al in HCl solution were studied by weight loss and thermometric methods in presence and in absence of stem extract of three different varieties of holy basil viz. ocimum basilicum (E{sub B}), ocimum canum (E{sub C}) and ocimum sanctum (E{sub S}). Inhibition efficiency increases with the increasing concentration of stem extract and decreases with increases in acid strength. Results show that all varieties under study are good corrosion inhibitors, among which, E{sub B} is most effective. Maximum inhibition efficiency was found 97.09% in 0.5N HCl solution with 0.6% stem extract. The Langmuir adsorption isotherm indicates that surface coverage also increases with increasing in the concentration of extract of stem in HCl solution.

Solvated electron: criticism of a suggested correlation of chemical potential with optical absorption energy

International Nuclear Information System (INIS)

Farhataziz, M.

1984-01-01

A recent theoretical treatment of the absorption spectrum of the solvated electron, e - sub(s), maintains that rigorously μ 0 >= -0.75 Esub(av), which gives empirical relationship, μ 0 >= -(0.93 +- 0.02)Esub(max). For e - sub(s) in a particular solvent at a temperature and pressure, μ 0 , Esub(av) and Esub(max) are standard chemical potential, average energy of the absorption spectrum and the energy at the absorption maximum respectively. The temperature and pressure effects on the absorption spectrum of e - sub(s) in water and liquid ammonia do not support the equality sign in the above cited relationships. The implications of inequality expressed above are discussed for e - sub(s) in water and liquid ammonia. (author)

Butyl paraben and propyl paraben modulate bisphenol A and estradiol concentrations in female and male mice

Energy Technology Data Exchange (ETDEWEB)

Pollock, Tyler; Weaver, Rachel E.; Ghasemi, Ramtin; Catanzaro, Denys de, E-mail: decatanz@mcmaster.ca

2017-06-15

People are routinely exposed to the antimicrobial preservatives butyl paraben (BP) and propyl paraben (PP), as well as the monomer of polycarbonate plastics, bisphenol A (BPA). These chemicals are reliably detected in human urine and potentially interact. We investigated whether BP or PP exposure can modulate the concentrations of {sup 14}C-BPA and 17β-estradiol (E{sub 2}). Female and male CF1 mice were each given a subcutaneous injection of oil containing 0 (vehicle), 1, 3, or 9 mg BP or PP, then given a dietary supplement containing 50 μg/kg {sup 14}C-BPA. Radioactivity was measured in tissues through liquid scintillation counting. Significantly elevated {sup 14}C-BPA concentrations were observed following BP treatment in blood serum of both sexes, as well as the lungs, uterus, and ovaries of females and the testes and epididymides of males. Treatment with PP significantly elevated {sup 14}C-BPA concentrations in the uterus only. In another experiment, female and male CF1 mice were each injected with vehicle, 3 mg BP, or 3 mg PP, and E{sub 2} was measured in urine 2–12 h later. Whereas PP did not affect E{sub 2}, BP significantly elevated E{sub 2} 6–10 h after injection in females and 8 h after injection in males. These data indicate that BP and PP can alter the pharmacokinetics of BPA in vivo, and that BP can modulate E{sub 2} concentrations. These results are consistent with evidence that parabens inhibit enzymes that are critical for BPA and E{sub 2} metabolism, and demonstrate the importance of considering concurrent exposure to multiple chemicals when determining regulatory exposure limits. - Highlights: • We studied whether paraben exposure affects the distribution of oral {sup 14}C-BPA. • Elevated {sup 14}C–BPA was observed in mice given butyl or propyl paraben. • We also studied whether paraben exposure affects natural E{sub 2} levels in urine. • Elevated E{sub 2} was observed in mice given butyl, but not propyl, paraben. • Parabens may

Determining estrogenic steroids in Taipei waters and removal in drinking water treatment using high-flow solid-phase extraction and liquid chromatography/tandem mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Chen, C.-Y. [Institute of Environmental Health, College of Public Health, National Taiwan University, 17 Hsu-Chou Road, Taipei (10055), Taiwan (China)]. E-mail: dbms@ntu.edu.tw; Wen, T.-Y. [Institute of Environmental Health, College of Public Health, National Taiwan University, 17 Hsu-Chou Road, Taipei (10055), Taiwan (China); Wang, G.-S. [Institute of Environmental Health, College of Public Health, National Taiwan University, 17 Hsu-Chou Road, Taipei (10055), Taiwan (China); Department of Public Health, College of Public Health, National Taiwan University, 17 Hsu-Chou Road, Taipei (10055), Taiwan (China); Cheng, H.-W. [Institute of Environmental Health, College of Public Health, National Taiwan University, 17 Hsu-Chou Road, Taipei (10055), Taiwan (China); Lin, Y.-H. [Institute of Environmental Health, College of Public Health, National Taiwan University, 17 Hsu-Chou Road, Taipei (10055), Taiwan (China); Lien, G.-W. [Institute of Environmental Health, College of Public Health, National Taiwan University, 17 Hsu-Chou Road, Taipei (10055), Taiwan (China)

2007-06-01

River water and wastewater treatment plant (WWTP) effluents from metropolitan Taipei, Taiwan were tested for the presence of the pollutants estrone (E{sub 1}), estriol (E{sub 3}), 17{beta}-estradiol (E{sub 2}), and 17{alpha}-ethinylestradiol (EE{sub 2}) using a new methodology that involves high-flow solid-phase extraction and liquid chromatography/tandem mass spectrometry. The method was also used to investigate the removal of the analytes by conventional drinking water treatment processes. Without adjusting the pH, we extracted 1-L samples with PolarPlus C{sub 18} Speedisks under a flow rate exceeding 100 mL/min, in which six samples could be done simultaneously using an extraction station. The adsorbent was washed with 40% methanol/60% water and then eluted by 50% methanol/50% dichloromethane. The eluate was concentrated until almost dry and was reconstituted by 20 {mu}L of methanol. Quantitation was done by LC-MS/MS-negative electrospray ionization in the selected reaction monitoring mode with isotope-dilution techniques. The mobile phase was 10 mM N-methylmorpholine aqueous solution/acetonitrile with gradient elution. Mean recoveries of spiked Milli-Q water were 65-79% and precisions were within 2-20% of the tested concentrations (5.0-200 ng/L). The method was validated with spiked upstream river water; precisions were most within 10% of the tested concentrations (10-100 ng/L) with most RSDs < 10%. LODs of the environmental matrixes were 0.78-7.65 ng/L. A pre-filtration step before solid-phase extraction may significantly influence the measurement of E{sub 1} and EE{sub 2} concentrations; disk overloading by water matrix may also impact analyte recoveries along with ion suppression. In the Taipei water study, the four steroid estrogens were detected in river samples (ca. 15 ng/L for E{sub 2} and EE{sub 2} and 35-45 ng/L for E{sub 1} and E{sub 3}). Average levels of 19-26 ng/L for E{sub 1}, E{sub 2}, and EE{sub 2} were detected in most wastewater effluents

Sex-specific vitellogenin production in immature rainbow trout

Energy Technology Data Exchange (ETDEWEB)

Carlson, D.B.; Williams, D.E.

1999-10-01

Many xenobiotics interact with hormone systems of animals, potentially leading to a phenomenon commonly called endocrine disruption. Much attention has focused on steroid hormone systems and corresponding receptor proteins, particularly estrogens. Vitellogenin (Vg) was measured in sexually immature rainbow trout (Oncorhynchus mykiss) exposed to 17{beta}-estradiol (E{sub 2}) in the diet. Mixed-sex populations of trout aged 3, 6, 12, or 18 months were maintained separately and fed E{sub 2} at 0.05 or 2.5 mg/kg for 7d. Females fed E{sub 2} at 0.05 mg/kg consistently produced three- to fourfold greater amounts of Vg than similarly aged males. Age- and sex-matched fish fed E{sub 2} at 2.5 mg/kg produced equivalent amounts of Vg. Sex differences in Vg production were apparent only at a dose of E{sub 2} (0.05 mg/kg) that results in submaximal Vg induction. Their results document the importance of considering the sex of juvenile fish when using Vg production as a marker of xenoestrogen exposure.

Charged particle flux near the Mars

International Nuclear Information System (INIS)

Vernov, S.N.; Tverskoj, B.A.; Yakovlev, V.A.

1974-01-01

The data on cosmic ray fluxes, obtained for the first time in the areocentric orbit by means of the 'Mars-2' satellite are given and discussed. The measurements were carried out on the variable solar cosmic ray flux background from December 14, 1971, to June 1, 1972. For this reason it is difficult to strictly separate local increases in the soft particle fluxes near the planet (electrons with Esub(e)>0.1 and 0.3MeV and protons with Esub(p)>1 and 5MeV) from the variation of corresponding particles of a solar origin. The detected intensities exceed the background which is caused by detection of particles of a galactic origin even at the complete overlap of the counter aperture by the planet. The possible causes of the detected irregularities in an intensity are discussed. It has been established definitely that neither Mars nor Venus have radiation belts at an election energy of Esub(e)>100KeV and proton energy of Esup(p)>1

Effects of alcohols on gas holdup and volumetric liquid-phase mass transfer coefficient in gel-particle-suspended bubble column

Energy Technology Data Exchange (ETDEWEB)

Salvacion, J.; Murayama, M.; Otaguchi, K.; Koide, K. [Tokyo Institute of Technology, Tokyo (Japan)

1995-08-20

The effects of alcohols, column dimensions, gas velocity, physical properties of liquids, and gel particles on the gas holdup e{sub G} and the volumetric liquid-phase mass transfer coefficient k{sub L}a in a gel-particle-suspended bubble column under liquid-solid batch operation were studied experimentally. It was shown that addition of at alcohols to water generally increases e{sub G}. However, k{sub L}a values in aqueous solutions of alcohols became larger or smaller than those in water, according to the kind and concentration of the alcohol added to water. It was also shown that the presence of suspended gel-particles in the bubble column reduces values of e{sub G} and k{sub L}a. Based on these observations, empirical equations for e{sub G} in the transition regime in an ethanol solution, for e{sub G} in the heterogeneous now regime applicable to various alcohol solutions and for k{sub L}a in both now regimes were proposed. 18 refs., 12 figs., 3 tabs.

A Deep Search with HST for Late Time Supernova Signatures in the Hosts of XRF 011030 and XRF 020427

Science.gov (United States)

Patel, Sandeep; Kouveliotou, Chryssa; Levan, Andrew; Fruchter, Andrew; Rol, Evert; Rhoads, James; Gorosabel, Javier; Ramirez-Ruiz, Enrico; Hjorth, Jens; Wijers, Ralph

2004-01-01

X-ray Flashes (XRFs), are, like Gamma-Ray Bursts (GRBs) thought to signal the collapse of massive stars in distant galaxies. Many models posit that the isotropic equivalent energies of XRFs are lower than those for GRBs, such that they are visible hom a reduced range of distances when compared with GRBs. Here we present the results of two epoch Hubble Space Telescope imaging of two XRFs. These images taken approximately 45 and 200 days post bust reveal no evidence for an associated supernova in either case. Supernovae such as SN 1998bw would have been visible out to z approximately 1.5 in each case, while faint supernovae such as SN 2002ap would be visible to z approximately 1. At these distances the bursts would not fit the observed correlations between E(sub p) and E(sub iso) and would have required extremely luminous X-ray afterglows. We conclude that should these XRFs reside at low redshift, it is necessary either that their line of sight is heavily extinguished, or that XRFs, unlike GRBs do not have temporally coincident supernovae.

Synchrotron self-inverse Compton radiation from reverse shock on GRB 120326A

Energy Technology Data Exchange (ETDEWEB)

Urata, Yuji [Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan (China); Huang, Kuiyun; Takahashi, Satoko [Academia Sinica Institute of Astronomy and Astrophysics, Taipei 106, Taiwan (China); Im, Myungshin; Kim, Jae-Woo; Jang, Minsung [Center for the Exploration of the Origin of the Universe, Department of Physics and Astronomy, FPRD, Seoul National University, Shillim-dong, San 56-1, Kwanak-gu, Seoul (Korea, Republic of); Yamaoka, Kazutaka [Solar-Terrestrial Environment Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601 (Japan); Tashiro, Makoto [Department of Physics, Saitama University, Shimo-Okubo, Saitama 338-8570 (Japan); Pak, Soojong, E-mail: urata@astro.ncu.edu.tw [School of Space Research, Kyung Hee University, Yongin, Gyeonggi 446-701 (Korea, Republic of)

2014-07-10

We present multi-wavelength observations of a typical long duration GRB 120326A at z = 1.798, including rapid observations using a Submillimeter Array (SMA) and a comprehensive monitoring in the X-ray and optical. The SMA observation provided the fastest detection to date among seven submillimeter afterglows at 230 GHz. The prompt spectral analysis, using Swift and Suzaku, yielded a spectral peak energy of E{sub peak}{sup src}=107.8{sub −15.3}{sup +15.3} keV and an equivalent isotropic energy of E{sub iso} as 3.18{sub −0.32}{sup +0.40}×10{sup 52} erg. The temporal evolution and spectral properties in the optical were consistent with the standard forward shock synchrotron with jet collimation (6.°69 ± 0.°16). The forward shock modeling, using a two-dimensional relativistic hydrodynamic jet simulation, was also determined by the reasonable burst explosion and the synchrotron radiation parameters for the optical afterglow. The X-ray light curve showed no apparent jet break and the temporal decay index relation between the X-ray and optical (αo – α{sub X} = –1.45 ± 0.10) indicated different radiation processes in each of them. Introducing synchrotron self-inverse Compton radiation from reverse shock is a possible solution, and the detection and slow decay of the afterglow in submillimeter supports that this is a plausible idea. The observed temporal evolution and spectral properties, as well as forward shock modeling parameters, enabled us to determine reasonable functions to describe the afterglow properties. Because half of the events share similar properties in the X-ray and optical as the current event, GRB 120326A will be a benchmark with further rapid follow-ups, using submillimeter instruments such as an SMA and the Atacama Large Millimeter/submillimeter Array.

Study of the giant multipole resonances especially of the isoscalar giant E2 resonance in 208Pb by medium and high energy resolution inelastic electron scattering

International Nuclear Information System (INIS)

Kuehner, G.

1982-01-01

In the nucleus 208 Pb giant multipole resonances up to excitation energies of Esub(x) = 35 MeV were looked for by medium resolution inelastic electron scattering. Twelve spectra were taken up at incident energies of E 0 = 45-65 MeV under scattering angles from upsilon = 93 0 to 165 0 . The cross sections extracted from this were analyzed by means of DWBA calculations using RPA amplitudes from a model with separable residual interaction. On the base of this analysis for the first time it could be shown that the maximum in the electron scattering cross section at Esub(x) approx.= 14 MeV can be consistently described as superposition of the Jsup(π) = 1 - , ΔT = 1 with a Jsup(π) = 0 + , ΔT = 0 giant resonance. Furthermore the spectra under backward scattering angles indicate the existence of a magnetic excitation at Esub(x) approx.= 15 MeV which is interpreted as Jsup(π) = 3 + giant resonance. Besides under forward angles a further weak excitation at Esub(x) approx.= 14.6 MeV appears which is very well compatible with Jsup(π) = 2 + . At Esub(x) = 17.5 MeV a Jsup(π) = 3 - resonance was found which recently is observed also in (α, α') experiments and therefore gets a ΔT = 0 assignment. A further resonance at Esub(x) approx.= 21 MeV has also a Jsup(π) = 3 - character but has to be partly assigned to a Jsup(π) = 1 - , ΔT = 0 excitation. At Esub(x) = 23.8 MeV a Jsup(π) = 2 + excitation was found which gets because of model predictions a ΔT = 1 assignment. (orig./HSI) [de

Possible viscosity effects in neutron-induced fission of 232Th and 238U

International Nuclear Information System (INIS)

Gindler, J.E.; Glendenin, L.E.; Wilkins, B.D.

1979-01-01

Fission yields induced in the 238 U(n,f) and 232 Th(n,f) reactions were determined as a function of incident neutron energy (E/sub n/). The ratio of 115 Cd-to- 140 Ba yields as a function of E/sub n/ is analyzed by means of the equation Y 1 /Y 2 = exp[2(a 1 (E/sub n/+E 1 )/sup 1/2/ -2(a 2 (E/sub n/+E 2 )/sup 1/2/] to give values of a/sub i/, the level density parameter, and E/sub i/, the excitation energy for E/sub n/=0. The energies E/sub i/ are interpreted on the basis of the liquid drop model with shell and pairing corrections. Values are deduced for the energy dissipated by viscosity effects in the descent from the saddle point to the point where masses are fixed in the fissioning nucleus. These values are 1.7 MeV for 232 Th(n,f) and 4.8 MeV for 238 U(n,f). These values are consistent with the experimental observation that anti ν/sub p/ is approx. 0.6 neutron greater for 239 U fission than for 233 Th fission and that strong odd--even (nucleon pairing) effects are found in the fragment total kinetic energy distribution for 230 Th fission but not for 234 U fission. The low dissipation energy values together with the low values of pre-scission kinetic energy deduced by Guet, et al., [Nucl. Phys. A134 (1971)1] indicate a shorter path from the saddle point of the fissioning nucleus to scission than is generally assumed in theoretical calculations. 31 references

Measurement and modeling of shortwave irradiance components in cloud-free atmospheres

Energy Technology Data Exchange (ETDEWEB)

Halthore, R.N.

1999-08-04

Atmosphere scatters and absorbs incident solar radiation modifying its spectral content and decreasing its intensity at the surface. It is very useful to classify the earth-atmospheric solar radiation into several components--direct solar surface irradiance (E{sub direct}), diffuse-sky downward surface irradiance (E{sub diffuse}), total surface irradiance, and upwelling flux at the surface and at the top-of-the atmosphere. E{sub direct} depends only on the extinction properties of the atmosphere without regard to details of extinction, namely scattering or absorption; furthermore it can be accurately measured to high accuracy (0.3%) with the aid of an active cavity radiometer (ACR). E{sub diffuse} has relatively larger uncertainties both in its measurement using shaded pyranometers and in model estimates, owing to the difficulty in accurately characterizing pyranometers and in measuring model inputs such as surface reflectance, aerosol single scattering albedo, and phase function. Radiative transfer model simulations of the above surface radiation components in cloud-free skies using measured atmospheric properties show that while E{sub direct} estimates are closer to measurements, E{sub diffuse} is overestimated by an amount larger than the combined uncertainties in model inputs and measurements, illustrating a fundamental gap in the understanding of the magnitude of atmospheric absorption in cloud-free skies. The excess continuum type absorption required to reduce the E{sub diffuse} model overestimate ({approximately}3--8% absorptance) would significantly impact climate prediction and remote sensing. It is not clear at present what the source for this continuum absorption is. Here issues related to measurements and modeling of the surface irradiance components are discussed.

Peierls' instability in a one-dimensional potentially metallic solid

International Nuclear Information System (INIS)

Valladares, A.A.; Cetina, E.A.; Sansores, L.E.

1980-01-01

The Peierls instability of one-dimensional potentially metallic lithium solid is investigated in the Hueckel and SCF approximations. In the Hueckel approximation Esub(F) is a monotonic increasing function of the displacement of every other atom of the lattice, whereas in the SCF approximation, where the filling of the bands is considered, Esub(F) shows the minimum predicted by Peierls. The energy gap (for the arrangement that minimizes Esub(F)) is 4.5 eV, indicating that this solid is an insulator. (author)

The 65 keV resonance in the {sup 17}O(p,alpha){sup 14}N thermonuclear reaction

Energy Technology Data Exchange (ETDEWEB)

Sergi, M.L. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Spitaleri, C. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Coc, A. [CSNSM, UMR 8609, CNRS/IN2P3and Universite Paris Sud 11, Batiment 104, 91405 Orsay Campus (France); Mukhamedzhanov, A. [Cyclotron Institute, Texas A and M University, College Station, TX 77843 (United States); Burjan, S.V. [Nuclear Physics Institute of ASCR Rez near Prague (Czech Republic); Gulino, M. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Hammache, F. [IPN, IN2P3-CNRS et Universite de Paris-Sud 11, 91406 Orsay Cedex (France); Hons, Z. [Nuclear Physics Institute of ASCR Rez near Prague (Czech Republic); Irgaziev, B. [GIK Institute of Engineering Sciences and Technology Topi District Swabi NWFP (Pakistan); Kiss, G.G. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Kroha, V. [Nuclear Physics Institute of ASCR Rez near Prague (Czech Republic); La Cognata, M. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Centro Siciliano di Fisica Nucleare e Struttura della Materia, Catania (Italy); Lamia, L.; Pizzone, R.G. [Laboratori Nazionali del Sud, Catania (Italy); Dipartimento di Metodologie Fisiche e Chimiche per l' Ingegneria, Universita di Catania, Catania (Italy); Sereville, N. de [IPN, IN2P3-CNRS et Universite de Paris-Sud 11, 91406 Orsay Cedex (France); Somorjai, E. [ATOMKI, Debrecen (Hungary)

2010-03-01

The indirect measurement of {sup 17}O(p,alpha){sup 14}N cross section was performed by means of the Trojan Horse Method. This approach allowed to investigate the ultra-low energy range (E{sub c.m.}=0-300 keV) relevant for several astrophysics environments, where two resonant levels of {sup 18}F at E{sub c.m.}{sup R}=65 keV and E{sub c.m.}{sup R}=183 keV play a significant role in the reaction rate determination.

Statistical method for the determination of the ignition energy of dust cloud - experimental validation

Energy Technology Data Exchange (ETDEWEB)

Bernard, S.; Lebecki, K.; Gillard, P.; Youinou, L.; Baudry, G. [University of Orleans, Bourges (France)

2010-05-15

Powdery materials such as metallic or polymer powders play a considerable role in many industrial processes. Their use requires the introduction of preventive safeguard to control the plants safety. The mitigation of an explosion hazard, according to the ATEX 137 Directive (1999/92/EU), requires the assessment of the dust ignition sensitivity. PRISME laboratory (University of Orleans) has developed an experimental set-up and methodology, using the Langlie test, for the quick determination of the explosion sensitivity of dusts. This method requires only 20 shots and ignition sensitivity is evaluated through the E{sub 50} (energy with an ignition probability of 0.5) A Hartmann tube, with a volume of 1.3l, was designed and built. Many results on the energy ignition thresholds of partially oxidised aluminium were obtained using this experimental device and compared to literature. E-50 evolution is the same as MIE but their respective values are different and MIE is lower than E{sub 50} however the link between E{sub 50} and MIE has not been elucidated In this paper, the Langlie method is explained in detail for the determination of the parameters (mean value E{sub 50} and standard deviation {sigma}) of the associated statistic law. The ignition probability versus applied energy is firstly measured for Lycopodium in order to validate the method A comparison between the normal and the lognormal law was achieved and the best fit was obtained with the lognormal law. In a second part, the Langlie test was performed on different dusts such as aluminium, cornstarch, lycopodium, coal, and PA12 in order to determine E-50 and {sigma} for each dust. The energies E{sub 05} and E{sub 10} corresponding respectively to an ignition probability of 0.05 and 0.1 are determined with the lognormal law and compared to MIE find in literature. E{sub 05} and E{sub 10} values of ignition energy were found to be very close and were in good agreement with MIE in the literature.

The electronic structure of molecules by a many-body approach. Pt. 1

International Nuclear Information System (INIS)

Niessen, W. von; Cederbaum, L.S.; Kraemer, W.P.

1976-01-01

The ionization potentials of benzene are studied by an ab initio many-body approach which includes the effects of electron correlation and reorganization beyond the one-particle approximation. The calculations confirm the assignment of the photoelectron spectrum experimentally proposed by Jonsson and Lindholm: 1esub(1g)(π), 2esub(2g), 1asub(2u)(π), 2esub(1u), 1bsub(2u), 1bsub(1u), 2asub(1g), 1esub(2g) in order of increasing binding energy. To definitely establish the ordering of the ionization potentials in the second band, which has been very controversial, the corresponding vibrational structure has been calculated. A number of one-electron properties are calculated in the one-particle approximation and compared to experimental work and other theoretical calculations. (orig.) [de

Radial electric field studies in the plasma edge of ASDEX upgrade

Energy Technology Data Exchange (ETDEWEB)

Viezzer, Eleonora

2012-12-18

In magnetically confined fusion plasmas, edge transport barriers (ETBs) are formed during the transition from a highly turbulent state (low confinement regime, L-mode) to a high energy confinement regime (H-mode) with reduced turbulence and transport. The performance of an H-mode fusion plasma is highly dependent on the strength of the ETB which extends typically over the outermost 5% of the confined plasma. The formation of the ETB is strongly connected to the existence of a sheared plasma flow perpendicular to the magnetic field caused by a local radial electric field E{sub r}. The gradients in E{sub r} and the accompanying E x B velocity shear play a fundamental role in edge turbulence suppression, transport barrier formation and the transition to H-mode. Thus, the interplay between macroscopic flows and transport at the plasma edge is of crucial importance to understanding plasma confinement and stability. The work presented in this thesis is based on charge exchange recombination spectroscopy (CXRS) measurements performed at the plasma edge of the ASDEX Upgrade (AUG) tokamak. During this thesis new high-resolution CXRS diagnostics were installed at the outboard and inboard miplane of AUG, which provide measurements of the temperature, density and flows of the observed species. From these measurements the radial electric field can be directly determined via the radial force balance equation. The new CXRS measurements, combined with the other edge diagnostics available at AUG, allow for an unprecedented, high-accuracy localization (2-3 mm) of the E{sub r} profile. The radial electric field has been derived from charge exchange spectra measured on different impurity species including He{sup 2+}, B{sup 5+}, C{sup 6+} and Ne{sup 10+}. The resulting E{sub r} profiles are found to be identical within the uncertainties regardless of the impurity species used, thus demonstrating the validity of the diagnostic technique. Inside the ETB the E{sub r} profile forms a deep

A COMPREHENSIVE STUDY OF GAMMA-RAY BURST OPTICAL EMISSION. II. AFTERGLOW ONSET AND LATE RE-BRIGHTENING COMPONENTS

Energy Technology Data Exchange (ETDEWEB)

Liang Enwei; Li Liang; Liang Yunfeng; Tang Qingwen; Chen Jiemin; Lu Ruijing; Lue Lianzhong [Department of Physics and GXU-NAOC Center for Astrophysics and Space Sciences, Guangxi University, Nanning 530004 (China); Gao He; Zhang, Bing; Lue Houjun [Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154 (United States); Wu Xuefeng [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Yi Shuangxi; Dai Zigao [School of Astronomy and Space Science, Nanjing University, Nanjing, Jiangsu 210093 (China); Zhang Jin; Wei Jianyan, E-mail: lew@gxu.edu.cn, E-mail: zhang@physics.unlv.edu [National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

2013-09-01

We continue our systematic statistical study of various components of gamma-ray burst (GRB) optical light curves. We decompose the early onset bump and the late re-brightening bump with empirical fits and analyze their statistical properties. Among the 146 GRBs that have well-sampled optical light curves, the onset and re-brightening bumps are observed in 38 and 26 GRBs, respectively. It is found that the typical rising and decaying slopes for both the onset and re-brightening bumps are {approx}1.5 and {approx} - 1.15, respectively. No early onset bumps in the X-ray band are detected to be associated with the optical onset bumps, while an X-ray re-brightening bump is detected for half of the re-brightening optical bumps. The peak luminosity is anti-correlated with the peak time L{sub p}{proportional_to}t{sub p}{sup -1.81{+-}0.32} for the onset bumps and L{sub p}{proportional_to}t{sub p}{sup -0.83{+-}0.17} for the re-brightening bumps. Both L{sub p} and the isotropic energy release of the onset bumps are correlated with E{sub {gamma},iso}, whereas no similar correlation is found for the re-brightening bumps. These results suggest that the afterglow onset bumps are likely due to the deceleration of the GRB fireballs. Taking the onset bumps as probes for the properties of the fireballs and their ambient medium, we find that the typical power-law index of the relativistic electrons is 2.5 and the medium density profile behaves as n{proportional_to}r {sup -1} within the framework of the synchrotron external shock models. With the medium density profile obtained from our analysis, we also confirm the correlation between the initial Lorentz factor ({Gamma}{sub 0}) and E{sub iso,{gamma}} in our previous work. The jet component that produces the re-brightening bump seems to be on-axis and independent of the prompt emission jet component. Its typical kinetic energy budget would be about one order of magnitude larger than the prompt emission component, but with a lower {Gamma

Interaction of hydrated electron with dietary flavonoids and phenolic acids. Rate constants and transient spectra studied by pulse radiolysis

Energy Technology Data Exchange (ETDEWEB)

Cai, Zhongli; Li, Xifeng; Katsumura, Yosuke [Tokyo Univ., Tokai, Ibaraki (Japan). Nuclear Engineering Research Lab

2000-03-01

The reaction rate constants and transient spectra of 11 flavonoids and 4 phenolic acids reacting with e{sub aq}{sup -} at neutral pH were measured. The results suggest that C{sub 4} keto group is the active site for e{sub aq}{sup -} to attack on flavonoids and phenolic acids, while the o-dihydroxy structure in B-ring, the C{sub 2,3} double bond, the C{sub 3}-OH group and glycosylation have little effects on the e{sub aq}{sup -} scavenging activities. (author)

ENERGETIC FERMI/LAT GRB 100414A: ENERGETIC AND CORRELATIONS

Energy Technology Data Exchange (ETDEWEB)

Urata, Yuji; Tsai, Patrick P. [Institute of Astronomy, National Central University, Chung-Li 32054, Taiwan (China); Huang, Kuiyun [Academia Sinica Institute of Astronomy and Astrophysics, Taipei 106, Taiwan (China); Yamaoka, Kazutaka [Department of Physics and Mathematics, Aoyama Gakuin University, 5-10-1, Fuchinobe, Sayamihara 229-8558 (Japan); Tashiro, Makoto S., E-mail: urata@astro.ncu.edu.tw [Department of Physics, Saitama University, Shimo-Okubo, Saitama 338-8570 (Japan)

2012-03-20

This study presents multi-wavelength observational results for energetic GRB 100414A with GeV photons. The prompt spectral fitting using Suzaku/WAM data yielded spectral peak energies of E{sup src}{sub peak} of 1458.7{sup +132.6}{sub -106.6} keV and E{sub iso} of 34.5{sup +2.0}{sub -1.8} Multiplication-Sign 10{sup 52} erg with z = 1.368. The optical afterglow light curves between 3 and 7 days were effectively fitted according to a simple power law with a temporal index of {alpha} = -2.6 {+-} 0.1. The joint light curve with earlier Swift/UVOT observations yields a temporal break at 2.3 {+-} 0.2 days. This was the first Fermi/LAT detected event that demonstrated the clear temporal break in the optical afterglow. The jet opening angle derived from this temporal break was 5.{sup 0}8, consistent with those of other well-observed long gamma-ray bursts (GRBs). The multi-wavelength analyses in this study showed that GRB 100414A follows E{sup src}{sub peak}-E{sub iso} and E{sup src}{sub peak}-E{sub {gamma}} correlations. The late afterglow revealed a flatter evolution with significant excesses at 27.2 days. The most straightforward explanation for the excess is that GRB 100414A was accompanied by a contemporaneous supernova. The model light curve based on other GRB-SN events is marginally consistent with that of the observed light curve.

Analyses of experimental observations of electron temperatures in the near wake of a model in a laboratory-simulated solar wind plasma

International Nuclear Information System (INIS)

Intriligator, D.S.; Steele, G.R.

1985-01-01

Laboratory experiments have been performed that show the effect on the electron temperature of inserting a spherical conducting model, larger than the Debye length, into a free-streaming high-energy (1 kv) unmagnetized hydrogen plasma. These experiments are the first electron temperature experiments conducted at energies and compositions directly relevant to solar wind and astrophysical plasma phenomena. The incident plasma parameters were held constant. A large number of axial profiles of the electron temperature ratios T/sub e//sub in// T/sub e//sub out/ behind the model downstream in the model wake are presented. A rigorous statistical approach is used in the analysis of the electron temperature ratio data in both our experimental laboratory data and in our reanalysis of the published data of others. The following new results ae obtained: (1) In energetic plasma flow there is no overall temperature enhancement in the near wake since the best fit to the T/sub e//sub i/n/ T/sub e//sub out/ data is a horizontal straight line having a mean value of 1.05; (2) No statistically significant electron temperature enhancement peaks or depressions exist in the near-wake region behind a model at zero potential in a high-energy plasma even at distances less than or equal to Ma, where M is the acoustic Mach number and a is the model radius. This implies a ''filling in'' of electrons in the wake region which may be due to the higher mobility of these energetic electrons. This mechanism may permit the solar wind electrons to significantly contribute to the maintenance of the nightside ionosphere at Venus

Structural dependence of threshold displacement energies in rutile, anatase and brookite TiO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Robinson, M., E-mail: marc.robinson@curtin.edu.au [Nanochemistry Research Institute, Curtin University, GPO Box U1987, Perth, WA 6845 (Australia); Marks, N.A. [Discipline of Physics and Astronomy, Curtin University, Perth, WA 6845 (Australia); Lumpkin, G.R. [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia)

2014-09-15

Systematic molecular dynamics simulations of low energy cascades have been performed to examine how threshold displacement events are effected by changes in crystal structure. Exploiting the structural proximity of the rutile, anatase and brookite polymorphs of TiO{sub 2}, a quantitative examination of defect production has been carried out including detailed defect analysis and the determination of values of the threshold displacement energy (E{sub d}). Across all polymorphs comparable values of E{sub d} are reported for oxygen at around 20 eV, with the value for Ti in rutile (73 ± 2 eV) significantly higher than that in brookite (34 ± 1 eV) and anatase (39 ± 1 eV). Quantifying defect formation probability as a function of Primary Knock-on Atom (PKA) energy, simulations in rutile indicate a consistent reduction in defect formation at energies higher than E{sub d} relative to anatase and brookite. Defect cluster analysis reveals a significant proportion of di-Frenkel pairs in anatase at Ti PKA energies around E{sub d}. These clusters, which are stabilised by the localisation of two Frenkel pairs, are associated with a recombination barrier of approximately 0.19 eV. As such, annihilation is likely under typical experimental conditions which suggests an expected increase in the measured Ti value of E{sub d}. Identical O defect populations produced at the threshold by the O PKA in both rutile and anatase explain the comparable values of E{sub d}. At higher O PKA energies, the commencement of defect production on both sublattices in anatase is observed in contrast to the confinement of defects to the O sublattice in rutile. The overall trends reported are consistent with in-situ irradiation experiments and thermal spike simulations, suggesting the contrasting radiation response of the polymorphs of TiO{sub 2} is apparent during the initial stages of defect production. - Highlights: • Systematic calculation of threshold displacement energies (E{sub d

Constraints on Lorentz Invariance Violation from Fermi -Large Area Telescope Observations of Gamma-Ray Bursts

Science.gov (United States)

Vasileiou, V.; Jacholkowska, A.; Piron, F.; Bolmont, J.; Courturier, C.; Granot, J.; Stecker, Floyd William; Cohen-Tanugi, J.; Longo, F.

2013-01-01

We analyze the MeV/GeV emission from four bright Gamma-Ray Bursts (GRBs) observed by the Fermi-Large Area Telescope to produce robust, stringent constraints on a dependence of the speed of light in vacuo on the photon energy (vacuum dispersion), a form of Lorentz invariance violation (LIV) allowed by some Quantum Gravity (QG) theories. First, we use three different and complementary techniques to constrain the total degree of dispersion observed in the data. Additionally, using a maximally conservative set of assumptions on possible source-intrinsic spectral-evolution effects, we constrain any vacuum dispersion solely attributed to LIV. We then derive limits on the "QG energy scale" (the energy scale that LIV-inducing QG effects become important, E(sub QG)) and the coefficients of the Standard Model Extension. For the subluminal case (where high energy photons propagate more slowly than lower energy photons) and without taking into account any source-intrinsic dispersion, our most stringent limits (at 95% CL) are obtained from GRB 090510 and are E(sub QG,1) > 7.6 times the Planck energy (E(sub Pl)) and E(sub QG,2) > 1.3×10(exp 11) GeV for linear and quadratic leading order LIV-induced vacuum dispersion, respectively. These limits improve the latest constraints by Fermi and H.E.S.S. by a factor of approx. 2. Our results disfavor any class of models requiring E(sub QG,1) < or approx. E(sub Pl)

Contribution of relativistic quantum chemistry to electron’s electric dipole moment for CP violation

Energy Technology Data Exchange (ETDEWEB)

Abe, M., E-mail: minoria@tmu.ac.jp; Gopakumar, G., E-mail: gopakumargeetha@gmail.com; Hada, M., E-mail: hada@tmu.ac.jp [Tokyo Metropolitan University, 1-1, Minami-Osawa, Hachioji-city, Tokyo 192-0397 (Japan); JST, CREST, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012 (Japan); Das, B. P., E-mail: das@iiap.ernet.in [Indian Institute of Astrophysics, Bangalore 560 034 (India); Tatewaki, H., E-mail: htatewak@nsc.nagoya-cu.ac.jp [Graduate School of Natural Sciences, Nagoya City University, Nagoya, Aichi 467-8501 (Japan); Mukherjee, D., E-mail: pcdm@iacs.res.in [Raman Center of Atomic, Molecular and Optical Sciences, IACS, Kolkata 700 032 (India)

2015-12-31

The search for the electric dipole moment of the electron (eEDM) is important because it is a probe of Charge Conjugation-Parity (CP) violation. It can also shed light on new physics beyond the standard model. It is not possible to measure the eEDM directly. However, the interaction energy involving the effective electric field (E{sub eff}) acting on an electron in a molecule and the eEDM can be measured. This quantity can be combined with E{sub eff}, which is calculated by relativistic molecular orbital theory to determine eEDM. Previous calculations of E{sub eff} were not sufficiently accurate in the treatment of relativistic or electron correlation effects. We therefore developed a new method to calculate E{sub eff} based on a four-component relativistic coupled-cluster theory. We demonstrated our method for YbF molecule, one of the promising candidates for the eEDM search. Using very large basis set and without freezing any core orbitals, we obtain a value of 23.1 GV/cm for E{sub eff} in YbF with an estimated error of less than 10%. The error is assessed by comparison of our calculations and experiments for two properties relevant for E{sub eff}, permanent dipole moment and hyperfine coupling constant. Our method paves the way to calculate properties of various kinds of molecules which can be described by a single-reference wave function.

Fission energy of uranium isotopes and transuranium elements

International Nuclear Information System (INIS)

Nemirovskij, P.Eh.; Manevich, L.G.

1981-01-01

A comparison is made between the prompt fission energy, Esub(pr), calculated from the mass and binding energy spectrum and the Esub(pr) value obtained from the experimental data on the kinetic energy of fragments, the energy of prompt neutrons and prompt γ-quanta. Basing on the data on β-decay chains of fission fragments, the energies of neutrinos, γ-quanta and β-electrons are obtained, which permits to calculate the actual energy released during fission. The calculations are performed for thermal neutron-induced fission, fast-neutron induced fission and for fission after bombardment with 14 MeV neutrons. The available experimental data on the fission fragment kinetic energy, prompt γ-quanta energy and fission neutron energy are presented. The comparison of the Esub(pr) values obtained experimentally for the thermal-neutron-induced fission with the calculated Esub(pr) value shows that for 233 U, 239 Pu, 241 Pu the agreement is rather favourable. For 235 U the agreement is within the error limits. As to the Esub(pr) values for the fast-neutron-induced fission, the agreement between the calculated and experimental data for all nuclides is quite good

Identification of rotating and vibrating tetrahedrons in the heavy nucleus {sup 208}Pb

Energy Technology Data Exchange (ETDEWEB)

Heusler, A.

2017-11-15

Ten known states in the heavy nucleus {sup 208}Pb at 2.6 < E{sub x} < 7.9 MeV are described by rotating and vibrating tetrahedrons. The 3{sup -} and 4{sup +} yrast states are the first members of the rotational band. A 2{sup ±} doublet state with the 2{sup +} yrast state as one member and the newly recognized 2{sup -} yrast state as the other member, the 1{sup -} yrast state, and the third 0{sup +} state are the heads of the three elementary tetrahedral rotating and vibrating bands. The newly recognized state at E{sub x} = 4142 keV was assigned spin 2 in 1975 and is suggested to have negative parity by the absent {sup 208}Pb(α, α{sup '}) excitation. Four more states at 5.7 < E{sub x} < 7.9 MeV are identified as the next members of the three elementary tetrahedral rotating and vibrating bands. The ambiguous spin assignment to the state at E{sub x} = 7020 keV is settled with 3{sup -}, the state at E{sub x} = 7137 keV is assigned 4{sup -}. (orig.)

Degradation of shape memory effect

International Nuclear Information System (INIS)

Vandermeer, R.A.

1983-01-01

An important parameter for deciding whether or not a SME alloy is suitable for practical applications is the magnitude of the strain reversal accompanying martensite reversion. This research is concerned with elucidating metallurgical factors that cause degradation of this heat-activated recovery strain, E/sub R/. After explaining what is meant by degradation, two manifestations of degradation recently identified in near-monotectoid uranium-niobium alloys are described. The first was associated with the onset of plastic deformation of the martensite beyond the reversible strain limit, E/sub L/; a reduction of E/sub R/ from 5.25% at 8% total strain, i.e. E/sub L/, to 2.9% at 12% total strain was observed. A second type of degradation depended strongly on the heating rate during reversion; the E/sub R/ for an imposed strain of 6.95% was reduced from a value of 5.25% to 1.3% when the heating rate was decreased from 40 0 /sec to 0.05 0 /sec. Degradation was attributed to a change in the transformation path and the interjection of time-dependent, low temperature aging reactions

Physical properties evolution of sputtered zirconium oxynitride films: effects of the growth temperature

Energy Technology Data Exchange (ETDEWEB)

Rizzo, A; Signore, M A; Mirenghi, L; Piscopiello, E; Tapfer, L [ENEA, Department of Physical Technologies and New Materials, SS7, Appia, km 706, 72100 Brindisi (Italy)

2009-12-07

Zirconium oxynitride (ZrNO) films were deposited by RF reactive magnetron sputtering in water vapour-nitrogen atmosphere varying the deposition temperature from RT to 600 {sup 0}C. Optical analysis, x-ray diffraction, x-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) are the employed characterization techniques to investigate the influence of the substrate temperature on the films physical properties. It was found that the variation of the substrate temperature from RT to 600 {sup 0}C caused a structural transition from cubic phase of Zr{sub 2}ON{sub 2} to ZrN one, as confirmed by TEM observations too. In particular, Forouhi-Bloomer dispersion equations for optical parameters (n and k) and deconvolution of XPS spectra allowed further chemical properties be elucidated. They also permitted identification of two oxynitride phases, {gamma} phase (E{sub g} = 1.94 eV) and {beta} phase (E{sub g} = 1.7 eV), and an over-stoichiometric nitride one. The use of [E{sub c} - E{sub v}] values helped to confirm further the distinction between ({gamma}, {beta})-phases and N-rich zirconium nitride compound, which is unachievable by using only E{sub g} values.

Anomaly-free chiral theories in six dimensions

International Nuclear Information System (INIS)

Green, M.B.; Schwarz, J.H.; West, P.C.

1985-01-01

The coupled N = 1 Yang-Mills plus supergravity theory in ten dimensions can be made anomaly-free for SO(32) or E/sub 8/ X E/sub 8/. Only the case of SO(32) is known to correspond to a superstring theory, which is probably necessary for a fully consistent quantum theory. Anomaly-free chiral theories in lower dimensions can be obtained by considering nontrivial compactifications (involving nonzero background gauge fields) of the ten-dimensional theory that satisfy a topological consistency condition. This paper considers the compactification of four dimensions on the manifold K/sub 3/ without requiring that the equations of motion be satisfied. This leads to a large number of anomaly-free chiral supersymmetric six-dimensional theories, corresponding to various ways of embedding U(1) factors in SO(32) or E/sub 8/ X E/sub 8/

Uniform angular overlap model interpretation of the crystal field effect in U(5+) fluoride compounds

Energy Technology Data Exchange (ETDEWEB)

Gajek, Z.; Mulak, J. (W. Trzebiatowski Inst. of Low Temperature and Structure Research, Polish Academy of Sciences, Wroclaw (Poland))

1990-11-01

The uniform interpretation of the crystal field effect in three different U(5+) fluoride compounds: CsUF{sub 6}, {alpha}-UF{sub 5} and {beta}-UF{sub 5} within the angular overlap model (AOM) is given. Some characteristic relations between the AOM parameters and their distance dependencies resulting from ab initio calculations are introduced and examined from a phenomenological point of view. The traditional simplest approach with only one independent parameter, i.e. e{sub {sigma}} with e{sub {pi}}:e{sub {sigma}} = 0.32 and e{sub {delta}} = 0, is shown to provide a consistent interpretation of the crystal field effect of the whole class of the compounds. The parameters obtained for one compound are easily and successfully extrapolated to others. The specificity and importance of the e{sub {delta}} parameter for 5f{sup 1} systems is discussed. (orig.).

Relation of the Dsub(st) index to the azimuth component of the interplanetary magnetic field vector during separate storms

International Nuclear Information System (INIS)

Kovalevskij, I.V.; Levitin, A.E.; Fedoseeva, M.K.

1984-01-01

A relation between the index Dsub(st) and azimuthal component Bsub(y) of interplanetary magnetic field (IMF) vector during several magnetic storms with Dsub(st) > 100nT is discussed. It is established that the relation between Dsub(st) index and Bsub(y) and Esub(z) component of electric interplanetary field (EIF) is closed than the relation between Dsub(st) and Bsub(z) component of IMF and Esub(y) component of EIF. Correlation coefficients of Dsub(st) and Bsub(y) and Esub(z) differ but slightly from each other

Determination of the differential cross-section in hadronic e+e--annihilation events with hard, isolated, neutral particles

International Nuclear Information System (INIS)

Makowsky, M.

1982-10-01

Hadronic e + e - -annihilation events have been measured, by the CELLO-detector at PETRA at the center of mass energy Esub(cm) = 34 GeV and Esub(cm) = 22 GeV. Those events with hard, isolated, neutral particles are selected and explored. At Esub(cm) = 34 GeV the predominant source of these isolated photons is found to be initial state bremsstrahlung of the e + e - -annihilation. The measured photon distributions as function of its energy and the total cross section are investigated. The agreement with QED-predictions is good. (orig.) [de

Total photon absorption

International Nuclear Information System (INIS)

Carlos, P.

1985-01-01

Experimental methods using real photon beams for measurements of total photonuclear absorption cross section σ(Tot : E/sub γ/) are recalled. Most recent σ(Tot : E/sub γ/)results for complex nuclei and in the nucleon resonance region are presented

Non-isothermal curing kinetics and physical properties of MMT-reinforced unsaturated polyester (UP) resins

Energy Technology Data Exchange (ETDEWEB)

Vargas, María A., E-mail: angelesvh@yahoo.com [Tecnológico de Estudios Superiores de Ecatepec, Av. Tecnológico S/N, Valle de Anáhuac, 55210 Ecatepec de Morelos (Mexico); Vázquez, H. [Universidad Autónoma Metropolitana-Iztapalapa, Departamento de Física, Av. San Rafael Atlixco 186, col. Vicentina, Mexico, D.F. 09340 (Mexico); Guthausen, G. [KIT, Pro2NMR at MVM and IBG, Karlsruhe (Germany)

2015-07-10

Highlights: • Non-isothermal DSC analysis results have shown that the addition of MMT to a UP resin produces a delay in the cure reaction. • The shape of experimental heat-flow DSC curves showed two exothermic peaks for all the samples at different heating rates. • The overall kinetic analysis was performed by isoconversional methods. • It was found that the dependence of the activation energy (E{sub a}) on degree of reaction (α) is complex. - Abstract: Cure behavior of unsaturated polyester (UP)/montmorillonite (MMT)/methyl ethyl ketone peroxide (MEKP)/cobalt octoate intercalated nanocomposites with various MMT loadings was investigated by dynamic differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). UP/MMT nanocomposites were prepared by sequential mixing. Non-isothermal DSC curves were obtained by applying heating rates ranging from 5 to 20 °C/min. They presented two exothermic peaks, which should correspond to two independent cure reactions. The effective activation energy E{sub a}, was determined by applying both the Kissinger’s and Starink’s methods. The results showed slightly higher activation energy for nanocomposites, except for UP/10-MMT. It was found that the dependence of E{sub a} on α is complex. All the systems in this study fitted Sesták–Berggren (SB) model in overall reaction controlled kinetics and the corresponding model parameters, n, m, A were obtained, but it was insufficient in depicting the complex reaction kinetics. Transmission electron microscopy data support the formation of a partially delaminated nanocomposite material. UP and nanocomposites showed similar behavior on thermal stability.

MO-C-17A-02: A Novel Method for Evaluating Hepatic Stiffness Based On 4D-MRI and Deformable Image Registration

Energy Technology Data Exchange (ETDEWEB)

Cui, T [Duke University, Durham, NC (United States); Liang, X [Duke Unversity, Durham, NC (United States); Czito, B; Palta, M; Bashir, M; Yin, F; Cai, J [Duke University Medical Center, Durham, NC (United States)

2014-06-15

Purpose: Quantitative imaging of hepatic stiffness has significant potential in radiation therapy, ranging from treatment planning to response assessment. This study aims to develop a novel, noninvasive method to quantify liver stiffness with 3D strains liver maps using 4D-MRI and deformable image registration (DIR). Methods: Five patients with liver cancer were imaged with an institutionally developed 4D-MRI technique under an IRB-approved protocol. Displacement vector fields (DVFs) across the liver were generated via DIR of different phases of 4D-MRI. Strain tensor at each voxel of interest (VOI) was computed from the relative displacements between the VOI and each of the six adjacent voxels. Three principal strains (E{sub 1}, E{sub 2} and E{sub 3}) of the VOI were derived as the eigenvalue of the strain tensor, which represent the magnitudes of the maximum and minimum stretches. Strain tensors for two regions of interest (ROIs) were calculated and compared for each patient, one within the tumor (ROI{sub 1}) and the other in normal liver distant from the heart (ROI{sub 2}). Results: 3D strain maps were successfully generated fort each respiratory phase of 4D-MRI for all patients. Liver deformations induced by both respiration and cardiac motion were observed. Differences in strain values adjacent to the distant from the heart indicate significant deformation caused by cardiac expansion during diastole. The large E{sub 1}/E{sub 2} (∼2) and E{sub 1}/E{sub 2} (∼10) ratios reflect the predominance of liver deformation in the superior-inferior direction. The mean E{sub 1} in ROI{sub 1} (0.12±0.10) was smaller than in ROI{sub 2} (0.15±0.12), reflecting a higher degree of stiffness of the cirrhotic tumor. Conclusion: We have successfully developed a novel method for quantitatively evaluating regional hepatic stiffness based on DIR of 4D-MRI. Our initial findings indicate that liver strain is heterogeneous, and liver tumors may have lower principal strain values

New method for the induction of therapeutic amenorrhea: low dose endometrial afterloading irradiation. Clinical and hormonal studies

Energy Technology Data Exchange (ETDEWEB)

Gronroos, M.; Turunen, T.; Raekallio, J.; Ruotsalinen, P.; Salmi, T. (Turku Univ. (Finland). Dept. of Obstetrics and Gynecology)

1982-08-01

The authors present a new method for the induction of therapeutic amenorrhea: low dose endometrial afterloading irradiation. The problem with this method has been how to inactivate the endometrium while maintaining the physiological function of the ovaries. In 5/29 young patients regular or irregular bleedings occurred after an endometrial dose of 11+-1 Gy. These subjects were given a repeat low dose intrauterine irradiation. Thereafter no bleedings were found in four out of five patients. Two to 9 years after the repeat irradiation the plasma levels of E/sub 1/, E/sub 2/, FSH and LH corresponded closely to those of healthy women in reproductive age in three out of five patients; some high plasma P levels indicated ovulation. In two patients the E/sub 1/, E/sub 2/, and P values were more likely postmenopausal but, on the other hand, FSH and LH values reproductive ones. 19 refs.

Pulse radiolysis of rhodamine dye solutions

International Nuclear Information System (INIS)

Kucherenko, E.A.; Kartasheva, L.I.; Pikaev, A.K.

1982-01-01

Applying the method of pulse radiolysis (5 MeV electrons) a study was made on intermediate products of rhodamine B radiolytic transformations in neutral aqueous and ethanol solutions. Rate constants of reactions of esub(aq) and OH with the dye (they are equal to (2.2+-0.3)x10 10 and (2.1+-0.3)x10 10 e/molxs, accordingly) as well as optical and kinetic characteristics of esub(aq), OH and H interaction products were measured. The nature of these products is concluded. It was found that in ethanol solutions the semirecovered form - electroneutral radical of rhodamine B - was the only intermediate product. It arises during the interaction of the dye with esub(s) (k=(9.2+-1.2)x10 9 e/molxs) and α-et hananol radical (k=(1.1+-0.1)x10 8 l/molxs). Properties of this product were investigated

Lectures on superstrings

International Nuclear Information System (INIS)

Green, M.B.

1986-01-01

Superstring theories have not yet been formulated in terms of a single compelling principle such as that of general relativity. However, enough is now known about the structure of these theories to justify the optimism that certain of them might be consistent quantum theories that unify gravity and the other forces. The fact that the quantum consistency of superstring theories restricts the possible ten-dimensional unifying symmetry groups to be E/sub 8/ x E/sub 8/ or SO(32) (or (Spin 32)/Z/sub 2/ which has the same algebra as SO(32)) is a novel development in particle physics. The case of E/sub 8/ x E/sub 8/ is particularly interesting since, in the process of compactification from ten to four dimensions, it can break to a realistic chiral symmetry group describing all the observed interactions and the spectrum of the known particles

Observation of the energy transfer sequence in an organic host–guest system of a luminescent polymer and a phosphorescent molecule

Energy Technology Data Exchange (ETDEWEB)

Basel, Tek; Sun, Dali; Gautam, Bhoj; Valy Vardeny, Z., E-mail: val@physics.utah.edu

2014-11-15

We used steady state optical spectroscopies such as photoluminescence and photoinduced absorption (PA), and magnetic-field PA (MPA) for studying the energy transfer dynamics in films and organic light emitting diodes (OLED) based on host–guest blends with different guest concentrations of the fluorescent polymer poly-[2-methoxy, 5-(2′-ethyl-hexyloxy)phenylene vinylene] (MEHPPV-host), and phosphorescent molecule PtII-tetraphenyltetrabenzoporphyrin [Pt(tpbp); guest]. We show that the energy transfer process between the excited states of the host polymer and guest molecule takes a ‘ping-pong’ type sequence, because the lowest guest triplet exciton energy, E{sub T}(guest), lies higher than that of the host, E{sub T}(host). Upon photon excitation the photogenerated singlet excitons in the host polymer chains first undergo a Förster resonant energy transfer process to the guest singlet manifold, which subsequently reaches E{sub T}(guest) by intersystem crossing. Because E{sub T}(guest)>E{sub T}(host) there is a subsequent Dexter type energy transfer from E{sub T}(guest) to E{sub T}(host). This energy transfer sequence has profound influence on the photoluminescence and electroluminescence emission spectra in both films and OLED devices based on the MEHPPV-Pt(tpbp) system. - Highlights: • We studied electroluminescence of OLEDs based on host–guest blends. • The emission efficiency decreases with the guest concentration. • We found a dominant Dexter energy transfer from the triplet(guest) to triplet(host). • Energy transfer occurs from the host to guest and back to the host again.

Investigation of the 34S(p,γ)35Cl reaction and resonant absorption applied to the excitation of bound states

International Nuclear Information System (INIS)

Sparks, R.J.

1976-01-01

The yield curve of the reaction 34 S(p,γ) 35 Cl has been measured over the energy range Esub(p) = 1.95 - 2.91 MeV. Proton energies and strengths of 84 resonances are given. The decay schemes of 38 selected resonances have been studied, and for these branching ratios and spin limits are presented. Angular distributions have been measured at four 34 S(p,γ) 35 Cl resonances, at Esub(x) = 8.63, 8.64, 8.95 and 9.08 MeV, giving spin-parity assignments Jsup(π) = 7/2 - , (3/2,5/2), 3/2 + and 5/2, respectively. Spins and parities have been determined for bound states at Esub(x) = 3.92, 4.11, 4.85 and 5.16 MeV, as Jsup(π) = 3/2 + , 7/2 + , (1/2,3/2), 7/2 - , respectively. Branching and mixing ratios have been obtained for the decay of the states at Esub(x) = 3.92, 4.11, 4.35 and 5.16 MeV. Transition strengths are presented for the first three of these. A resonant absorption experiment at the Esub(p) = 2.79 MeV resonance gives for the resonance width GAMMA = 65 +- 20 eV, and also determines the partial widths GAMMAsub(γ), GAMMAsub(p) and GAMMAsub(p1). The level at 7064.3 +- 0.5 keV in 208 Pb has been excited in a resonant absorption experiment by Doppler shifted γ-radiation from the 34 S(p,γ) 35 Cl reaction at Esub(p) = 1974 keV. (Auth.)

Formation conditions for electron internal transport barriers in JT-60U plasmas

Energy Technology Data Exchange (ETDEWEB)

Fujita, T [Japan Atomic Energy Research Institute, Naka Fusion Research Establishment, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Fukuda, T [Osaka University, Suita, Osaka 565-0871 (Japan); Sakamoto, Y [Japan Atomic Energy Research Institute, Naka Fusion Research Establishment, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Ide, S [Japan Atomic Energy Research Institute, Naka Fusion Research Establishment, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Suzuki, T [Japan Atomic Energy Research Institute, Naka Fusion Research Establishment, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Takenaga, H [Japan Atomic Energy Research Institute, Naka Fusion Research Establishment, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Ida, K [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Idei, H [Kyushu University, Kasuga, Fukuoka 816-8580 (Japan); Shimozuma, T [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Fujisawa, A [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Ohdachi, S [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Toi, K [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan)

2004-05-01

The formation of electron internal transport barriers (ITBs) was studied using electron cyclotron (EC) heating in JT-60U positive shear (PS) and reversed shear (RS) plasmas with scan of neutral beam (NB) power. With no or low values of NB power and with a small radial electric field (E{sub r}) gradient, a strong, box-type electron ITB was formed in RS plasmas while a peaked profile with no strong electron ITBs was observed in PS plasmas within the available EC power. When the NB power and the E{sub r} gradient were increased, the electron transport in strong electron ITBs with EC heating in RS plasmas was not affected, while electron thermal diffusivity was reduced in conjunction with the reduction of ion thermal diffusivity, and strong electron and ion ITBs were formed in PS plasmas.

Calibration efficiency of HPGe detector in the 50-1800 KeV energy range; Calibracao em eficiencia de um detector HPGe na faixa de energias 50 - 1800KeV

Energy Technology Data Exchange (ETDEWEB)

Venturini, Luzia [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Servico de Monitoracao Ambiental

1996-07-01

This paper describes the efficiency of an HPGe detector in the 50 - 1800 keV energy range, for two geometries for water measurements: Marinelli breaker (850 ml) and a polyethylene flask (100 ml). The experimental data were corrected for the summing effect and fitted to a continuous, differentiable and energy dependent function given by 1n({epsilon})=b{sub 0}+b{sub 1}.1n(E/E{sub 0})+ {beta}.1n(E/E{sub 0}){sup 2}, where {beta} = b{sub 2} if E>E{sub 0} and {beta} =a{sub 2} if E {<=}E{sub 0}; {epsilon} = the full absorption peak efficiency; E is the gamma-ray energy and {l_brace}b{sub 0}, b{sub 1}, b{sub 2}, a{sub 2}, E{sub 0} {r_brace} is the parameter set to be fitted. (author)

Air shower detection and the energy flow in electromagnetic cascades

Energy Technology Data Exchange (ETDEWEB)

Stanev, Todor (Nuclear Power Oversight Committee (United States)); Vankov, H.P. (Bylgarska Akademiya na Naukite, Sofia (Bulgaria). Inst. za Yadrena Izsledvaniya i Yadrena Energetika)

1992-02-01

We study the longitudinal behaviour of the energy carried by the shower particles E{sub c} and its lateral distribution, give simple parametrizations of the results of Monte Carlo simulations, and discuss the advantages of shower detectors that measure directly E{sub c}. (author).

Characterization of Direct Piezoelectric Properties for Vibration Energy Harvesting

Energy Technology Data Exchange (ETDEWEB)

Yoshimura, Takeshi; Miyabuchi, Hiroki; Ashida, Atsushi; Fujimura, Norifumi [Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka, 599-8531 (Japan); Murakami, Syuichi, E-mail: tyoshi@pe.osakafu-u.ac.jp [Technology Research Institute of Osaka Prefecture, 2-7-1 Ayumino, Izumi, Osaka, 594-1157 (Japan)

2011-10-29

Direct piezoelectric effect of Pb(Zr,Ti)O{sub 3} (PZT) thin films was investigated to discuss the application of ferroelectric films to vibration energy harvesting. From the model of the piezoelectric vibration energy harvester, it was found that the figure of merit (FOM) is proportional of the square of the effective transverse piezoelectric coefficient e{sub 31,f}. The e{sub 31,f} coefficient of PZT films were measured by substrate bending method. Furthermore, it was found that the e{sub 31,f} coefficient increases with increasing strain, which is favourable for the vibration energy harvesting.

Near-bandgap optical properties of pseudomorphic GeSn alloys grown by molecular beam epitaxy

Energy Technology Data Exchange (ETDEWEB)

D' Costa, Vijay Richard, E-mail: vdcosta@asu.edu; Wang, Wei; Yeo, Yee-Chia, E-mail: eleyeoyc@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117583 (Singapore)

2016-08-14

We investigated the compositional dependence of the near-bandgap dielectric function and the E{sub 0} critical point in pseudomorphic Ge{sub 1-x}Sn{sub x} alloys grown on Ge (100) substrate by molecular beam epitaxy. The complex dielectric functions were obtained using spectroscopic ellipsometry from 0.5 to 4.5 eV at room temperature. Analogous to the E{sub 1} and E{sub 1}+Δ{sub 1} transitions, a model consisting of the compositional dependence of relaxed alloys along with the strain contribution predicted by the deformation potential theory fully accounts for the observed compositional dependence in pseudomorphic alloys.

Slowing of a fast electron beam in a plasma in an intense electromagnetic wave

Energy Technology Data Exchange (ETDEWEB)

Karapetyan, R.V.; Fedorov, M.V.

1980-01-01

The slowing of a fast electron beam as it penetrates into a plasma in a strong external electromagnetic field is studied. The effective collision frequency ..nu../sub p/ which is responsible for the slowing is derived in the dipole approximation; many-photon stimulated bremsstrahlung and inverse bremsstrahlung are taken into account. The asymptotic behavior of ..nu../sub p/ in strong wave fields E/sub 0/ is found. The results show that ..nu../sub p/ falls off with increasing E/sub 0/, because of a decrease in the frequency of collisions with plasma ions proportional to E/sub 0//sup -1/.

Room temperature ferromagnetism and phonon properties of pure and doped TiO{sub 2} nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Apostolova, I.N. [University of Forestry, Faculty of Forest Industry, 10, Kl. Ohridsky Blvd., 1756 Sofia (Bulgaria); Apostolov, A.T. [University of Architecture, Civil Engineering and Geodesy, Faculty of Hydrotechnics, Department of Physics, 1, Hristo Smirnenski Blvd., 1046 Sofia (Bulgaria); Bahoosh, S.G. [Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle (Germany); Wesselinowa, J.M., E-mail: julia@phys.uni-sofia.bg [University of Sofia, Department of Physics, 5, J. Bouchier Blvd., 1164 Sofia (Bulgaria)

2014-03-15

We have considered the origin of RTFM in TiO{sub 2} nanoparticles (NPs). Further we have studied the properties of the E{sub g1} phonon mode. The phonon frequency of anatase TiO{sub 2} NPs increases whereas in the case of rutile TiO{sub 2} NPs it decreases as the particle size decreases. The phonon damping is always enhanced in the nanosized materials. The hardening of the E{sub g1} mode and the softening of the E{sub g3} mode in anatase TiO{sub 2} NPs could be explained with the different anharmonic spin–phonon interaction constants of these modes. The doping effects with different transition metal ions on the E{sub g1} phonon mode are also discussed. - Highlights: • The origin of RTFM in TiO{sub 2} nanoparticles is investigated. • With decreasing of particle size the phonon frequency of anatase and rutile TiO{sub 2} NPs increases and decreases, respectively. • This could be explained with the different anharmonic spin–phonon interaction constants of these modes. • The phonon damping is always enhanced in the nanosized materials. • The doping effects with different transition metal ions on the E{sub g1} phonon mode are also discussed.

Behaviour of the interplanetary and magnetospheric electric fields during very intense storms

International Nuclear Information System (INIS)

Wu, Lei; Gendrin, R.; Higel, B.

1982-01-01

A study is made of the role which a positive (northward) component of the interplanetary magnetic field (IMF) Bsub(z) may play in triggering large magnetic storms. The study is made over a 15 year period (1964-1978) by selecting storms with Ksub(p) >= 7 0 and which are preceded by a Sudden Commencement (Ssc). The correlation between the geomagnetic index Ksub(m) and the three-hourly averaged Bsub(z) is established both on a statistical basis and on a case-by-case study. Storms associated with Bsub(z) > 0 are found to be less intense than those associated with Bsub(z) < 0, but major storms can be also triggered by solar wind events associated with a northward IMF. The relation-ship between interplanetary electric field Esub(γ) and Ksub(m) is also given. By using this relation together with the one between Esub(M) and Ksub(m) which has been established in previous studies (where Esub(M) is the magnetospheric convection electric field), it is possible to study the transfer efficiency of the magnetosphere. It is found that the transfer coefficient ΔEsub(M)/ΔEsub(γ) is much smaller for intense storms than for moderate ones, the latter having been studied in a previous paper (Wu Lei et al., 1981)

/sup 6/Li (e, e'X) reaction

Energy Technology Data Exchange (ETDEWEB)

Taneichi, H; Ueno, H [Yamagata Univ. (Japan); Shoda, K

1974-12-01

The target is a 99.3% enriched /sup 6/Li plate with thickness of 1.82 mg/cm/sup 2/. The energy of the electron beam ranged from 15 MeV to 31.7 MeV. Reaction products were measured by BDM which was set at the position of thetasub( l)=90/sup 0/. The (..gamma.., p) reaction was performed, the cross section was obtained. From the area ratio of P/sub 0/ and P/sub 1/ in a difference spectrum, sigma sub(p/sub 1/)/sigma sub(p/sub 0/)--3 was obtained. The cross section of the (..gamma.., t) reaction was acquired by a deduction method from two reaction spectra at Esub(e)=25 and 30 MeV. From the cross section, a reduced width theta/sup 2/--0.6 was obtained. The (..gamma.., d) reaction was measured at Esub(e)=15 MeV, and the cross section was obtained in the range from Esub(x)=8 MeV to 19 MeV by introducing previous data. The magnitude of the cross section was 0.2 to 0.1 ..mu..b/sr. The deuteron measured in this reaction must be identified whether it comes from T-impurity or E2. For the identification of this deuteron, an angular distribution measurement is needed.

Determination of trapping parameters of dosimetric thermoluminescent glow peak of lithium triborate (LiB{sub 3}O{sub 5}) activated by aluminum

Energy Technology Data Exchange (ETDEWEB)

Kafadar, V. Emir [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey); Yazici, A. Necmeddin, E-mail: yazici@gantep.edu.t [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey); Yildirim, R. Gueler [University of Gaziantep, Department of Engineering Physics, 27310 Gaziantep (Turkey)

2009-07-15

Lithium triborate (LBO) is a newly developed ideal nonlinear optical (NLO) crystal used in laser weapon, welder, radar, tracker, surgery, communication, etc. The effective atomic number (Z{sub eff}=7.3) makes it a tissue equivalent material and this encourages studies on its thermoluminescence (TL) properties for a radiation dosimetry. The previous studies have shown that Al-doped LiB{sub 3}O{sub 5} is a promising thermoluminescent dosimetric (TLD) material for dosimetric purposes and continuous and systematic investigations to improve its quality to get ones suited for dosimeter applications are worthy. In the given study, the additive dose (AD), initial rise with partial cleaning (IR), variable heating rate (VHR), peak shape (PS), three-points method (TPM) and computerized glow deconvolution (CGCD) methods were used to determine the kinetic parameters, namely the order of kinetics (b), activation energy (E{sub a}) and the frequency factor (s) associated with the dosimetric thermoluminescent glow peak (P3) of Al-doped LiB{sub 3}O{sub 5} after different dose levels with beta-irradiation.

(3He,α) reaction mechanism at high energy and neutron inner shell structure

International Nuclear Information System (INIS)

Wiele, J. van de.

1980-01-01

The ( 3 He,α) reaction on 12 C, 16 O, 28 Si, 58 Ni, 90 Zr, 118 Sn, 124 Sn and 208 Pb targets has been studied at Esub( 3 He) = 217 MeV (or 205 MeV) in order to investigate the reaction mechanism at high energy and large momentum transfer. The reaction yields large cross sections at very forward angles and strongly enhances the largest orbital momentum transfer. The angular distribution shapes are well reproduced in the frame-work of the Z-R- D.W.B.A. analysis if we use a unique empirical α-potential: Vsub(α)(Esub(α)) = Vsub( 3 He)(3/4 Esub(α)) + Vsub(n)(1/4 Esub(α)). The excitation energy spectra have been measured up to 100 MeV in the residual light and medium nuclei and up to about 16 MeV in heavy nuclei. In addition to the well-known low-lying levels, peaks or broad structures are observed for each nucleus at higher excitation energies. They are attributed to pick up from inner shells: 1s( 11 C and 15 O), 1p( 27 Si), 1d5/2 + 1p( 57 Ni), 1f7/2( 89 Zr) 1g9/2 117 Sn, 123 Sn and 1h11/2( 207 Pb). Selectivity and localization of direct and indirect pick up ( 3 He,α) reactions were studied. Finite range calculations show that this reaction is not very sensitive to the details of the range from function but only to D 0 coefficient and range R. A microscopic α-nucleus optical potential calculated with n-n dependent and independent density forces is able to reproduce both elastic scattering and pick up reaction angular distributions [fr

Neutron sources and its dosimetric characteristics; Fuentes de neutrones y sus caracteristicas dosimetricas

Energy Technology Data Exchange (ETDEWEB)

Vega C, H.R.; Manzanares A, E.; Hernandez D, V.M.; Mercado S, G.A. [Universidad Autonoma de Zacatecas, A.P. 336, 98000 Zacatecas (Mexico); Gallego D, E.; Lorente F, A. [Universidad Politecnica de Madrid, C/Jose Gutierrez Abascal 2, E-28006 Madrid (Spain)

2005-07-01

By means of Monte Carlo methods the spectra of the produced neutrons {sup 252} Cf, {sup 252} Cf/D{sub 2}O, {sup 241} Am Be, {sup 239} Pu Be, {sup 140} La Be, {sup 239} Pu{sup 18}O{sub 2} and {sup 226} Ra Be have been calculated. With the information of the spectrum it was calculated the average energy of the neutrons of each source. By means of the fluence coefficients to dose it was determined, for each one of the studied sources, the fluence factors to dose. The calculated doses were H, H{sup *}(10), H{sub p,sIab} (10, 0{sup 0}), E{sub AP} and E{sub ISO}. During the phase of the calculations the sources were modeled as punctual and their characteristics were determined to 100 cm in the hole. Also, for the case of the sources of {sup 239} Pu Be and {sup 241} Am Be, were carried out calculations modeling the sources with their respective characteristics and the dosimetric properties were determined in a space full with air. The results of this last phase of the calculations were compared with the experimental results obtained for both sources. (Author)

Isochronal and isothermal crystallization kinetics of amorphous Fe-based alloys

Energy Technology Data Exchange (ETDEWEB)

Zhang, J.T. [Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Wang, W.M., E-mail: weiminw@sdu.edu.cn [Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Key Lab of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004 (China); Ma, H.J.; Li, G.H.; Li, R.; Zhang, Z.H. [Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061 (China)

2010-06-10

Using the differential scanning calorimetry (DSC), the isochronal and isothermal crystallization kinetics of amorphous Fe{sub 61}Co{sub 9-x}Zr{sub 8}Mo{sub 5}W{sub x}B{sub 17} (x = 0 and 2) ribbons was investigated by the Kissinger equation and by the Kolmogorov-Johnson-Mehl-Avrami and Ranganathan-Heimendahl equations, respectively. The results show that tungsten can improve the activation energy E{sub 1}{sup K} for the first crystallization in the isochronal annealing process and activation energy E{sub n} for the nucleation in the isothermal annealing process, which can be ascribed to the dissolution of tungsten in the amorphous phase. Meanwhile, tungsten can decrease the activation energy E{sub 2}{sup K} for the second crystallization in the isochronal annealing process and growth activation energy E{sub g} in the isothermal annealing process, which is possibly associated with the formation of W-rich compound after the early nucleation process.

Coulomb displacement energies and neutron density distributions

International Nuclear Information System (INIS)

Shlomo, S.

1979-01-01

We present a short review of the present status of the theory of Coulomb displacement energies, ΔEsub(c), discussing the Okamoto-Nolem-Schiffer anomaly and its solution. We emphasize, in particular, that contrary to previous hopes, ΔEsub(c) does not determine rsub(ex), the root-mean square (rms) radius of the excess (valence) neutron density distribution. Instead, ΔEsub(c) is very sensitive to the value of Δr = rsub(n) - rsub(p), the difference between the rms radii of the density distributions of all neutrons and all protons. For neutron rich nuclei, such as 48 Ca and 208 Pb, a value of Δr = 0.1 fm is found to be consistent with ΔEsub(c). This value of Δr, which is considerably smaller than that (of 0.2 - 0.3 fm) predicted by some common Hartree-Fock calculations, seems to be confirmed by very recent experimental results. (orig.)

Study of the 6Li+16O light heavy-ion system around the Coulomb barrier

International Nuclear Information System (INIS)

Glasner, K.; Ricken, L.; Kuhlmann, E.

1986-01-01

Total cross sections of the light heavy-ion reactions 16 O( 6 Li,p) 21 Ne, i=0-10, have been measured for beam energies Esub(Li)=4.5-8.0 MeV in steps of 100 keV. Additional excitation functions of the inclusive reactions 16 O( 6 Li,xy), x=p, n and α, were taken for Esub(li)=4.1-12.5 MeV. The 6 Li+ 16 O reaction can be understood as a predominant compound-nucleus process as extensive Hauser-Feshbach calculations show. A comprehensive statistical analysis yields a coherence width GAMMA=130+-20 keV for Esub(x)( 22 Na)approx.=19 MeV. Statistically significant deviations from pure fluctuation phenomena are found in most excitation functions at Esub(x)( 22 Na)=17.9, 18.4, 19.2 and 20.2 MeV. Interpreting these structures with widths 400<=GAMMAsub(tot)<=800 keV as intermediate-width resonances in terms of rotational band, tentative spin assignments can be given. (orig.)

Plasmaspheric noise radiation during geomagnetic storms

International Nuclear Information System (INIS)

Larkina, V.I.; Likhter, Ya.I.

1981-01-01

Variations of plasmospheric background radiations during geomagnetic storms of different intensity are investigated. Used are results of ELF and VLF radiation measurements as well as electron fluxes of energies Esub(e)>40 keV carried out by Intercosmos 3 and Intercosmos 5 satellites. Dependences of radiation amplitude variations at 1.6 and 25 kHz frequencies on L shell for various geomagnetic activity in the day-time as well as data on variations of quasicaptured electron fluxes at Esub(e)>40 keV, are given. It is shown that experimental data agree with the existing theories of plasmospheric noise excitation. It is concluded that the plasmospheric noise excitation area Lsub(max) is always in the region of gap between radiation belts and inner slope of external radiation belt during magnetic storms. During magnetic storms Lsub(max) area moves simultaneously with the area, where particle flux of the external radiation belt is the most intensive [ru

Thermoelectric properties of TbFe{sub 2} and TbCo{sub 2} in C15- laves phase: Spin-polarized DFT+U approach

Energy Technology Data Exchange (ETDEWEB)

Reshak, A.H., E-mail: maalidph@yahoo.co.uk [New Technologies - Research Centre, University of West Bohemia, Univerzitni 8, Pilsen 306 14 (Czech Republic); School of Material Engineering, University Malaysia Perlis, Kangar, Perlis 01007 (Malaysia)

2017-01-15

Thermoelectric properties of materials are intimately related to their electronic band structure. Combining first- and second-principles calculations, we have obtained the transport properties for the spin-up and spin-down electrons of the laves phase TbFe{sub 2} and TbCo{sub 2} compounds. The unique band structure feature and the density of states at Fermi level (E{sub F}) promote the E{sub F} to a point where carriers are in energetic proximity to these features. The non-zero density of states at E{sub F} for the spin-up (↑) and spin-down (↓) electrons leads to unusual transport properties because both the (↑) and (↓) densities contributes to the states at E{sub F}. The parabolic bands in the vicinity of E{sub F} enhance the carriers mobility and hence the transport properties of TbFe{sub 2} and TbCo{sub 2}. Calculations show that the spin-up/down transport coefficients are temperature-dependent. It has been found that TbCo{sub 2} possess larger Seebeck coefficient than that of TbFe{sub 2} and hence the power factor. The calculated Seebeck coefficient of TbCo{sub 2} agree well with the available experimental data. - Highlights: • The transport properties of TbFe{sub 2} and TbCo{sub 2} are obtained. • The non-zero density of states at E{sub F} leads to unusual transport properties. • Spin-up/down transport coefficients are temperature-dependent. • The calculated Seebeck coefficient of TbCo{sub 2} agree with the experimental data. • TbCo{sub 2} possesses larger Seebeck coefficient than that of TbFe{sub 2}.

The motion of hydrogen isotopes in metals and intermetallic compounds

International Nuclear Information System (INIS)

Drexel, W.; Murani, A.; Tocchetti, D.; Kley, W.

1976-08-01

The existence of local and band modes of hydrogen and deuterium impurities in α-palladium hydride was observed by inelastic scattering of thermal neutrons of 12.6 meV. The first and second harmonic of the hydrogen local mode could be observed at Esub(1)sup(H)=(66+-4)meV and Esub(2)sup(H)=(135+-15)meV. For deuterium the first harmonics appears at Esub(1)sup(D)=(48+-4)meV. The width of the hydrogen local mode Esub(1)sup(H) is changing from 30 to 20 meV and its position from 63 to 66meV if the hydrogen concentration is altered from 2.7 to 0.2 atom percent. The intensity of the Esub(1)sup(H) mode, integrated for scattering angles from 11 0 till 68 0 and a mean k-vector pointing in the [210]-direction, is decreasing by a factor of 5 with respect to harmonic oscillator while the intensity of the second harmonic Esub(2)sup(H) and of the band modes stays almost constant if the temperature is changed from 423 0 K till 673 0 K. The behavior of this intensity distributions with temperature indicates a partition of the proton motions in diffusive and localized motions and supports the assumption of an anharmonic periodic potential along the [110] direction. The frequency distribution function of the hydrogen band modes has a shape as expected from measured dispersion curves. For [Pdsub(0.018)sup(D)-Pd] a broad quasielastic line is observed that indicates the existence of overdamped phonons in the vicinity of the impurity atom

Towards a new strategy of searching for QCD phase transition in heavy ion collisions

Energy Technology Data Exchange (ETDEWEB)

Ploszajczak, M. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); Shanenko, A.A. [Joint Inst. for Nuclear Research, Dubna (Russian Federation). Lab. of Theoretical Physics; Toneev, V.D. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France)]|[Joint Inst. for Nuclear Research, Dubna (Russian Federation). Lab. of Theoretical Physics

1995-12-31

The Hung and Shuryak arguments are reconsidered in favour of searching for the deconfinement phase transition in heavy ion collisions downward from the nominal SPS energy, at E{sub lab} {approx} 30 GeV/A where the fireball lifetime is the longest one. Using the recent lattice QCD data and the mixed phase model, it is shown that the deconfinement transition might occur at the bombarding energies as low as E{sub lab} = 3-5 GeV/A. Attention is drawn to the study of the mixed phase of nuclear matter in the collision energy range E{sub lab} = 2-10 GeV/A. (author). 18 refs.

Global energetics of solar flares. I. Magnetic energies

Energy Technology Data Exchange (ETDEWEB)

Aschwanden, Markus J. [Lockheed Martin, Solar and Astrophysics Laboratory, Org. A021S, Bldg. 252, 3251 Hanover Street, Palo Alto, CA 94304 (United States); Xu, Yan; Jing, Ju, E-mail: aschwanden@lmsal.com, E-mail: yan.xu@njit.edu, E-mail: ju.jing@njit.edu [Space Weather Research Laboratory, Center for Solar-Terrestrial Research, New Jersey Institute of Technology, 323 Martin Luther King Boulevard, Newark, NJ 07102-1982 (United States)

2014-12-10

We present the first part of a project on the global energetics of solar flares and coronal mass ejections that includes about 400 M- and X-class flares observed with Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO). We calculate the potential (E{sub p} ), the nonpotential (E {sub np}) or free energies (E {sub free} = E {sub np} – E{sub p} ), and the flare-dissipated magnetic energies (E {sub diss}). We calculate these magnetic parameters using two different NLFFF codes: the COR-NLFFF code uses the line-of-sight magnetic field component B{sub z} from HMI to define the potential field, and the two-dimensional (2D) coordinates of automatically detected coronal loops in six coronal wavelengths from AIA to measure the helical twist of coronal loops caused by vertical currents, while the PHOT-NLFFF code extrapolates the photospheric three-dimensional (3D) vector fields. We find agreement between the two codes in the measurement of free energies and dissipated energies within a factor of ≲ 3. The size distributions of magnetic parameters exhibit powerlaw slopes that are approximately consistent with the fractal-diffusive self-organized criticality model. The magnetic parameters exhibit scaling laws for the nonpotential energy, E{sub np}∝E{sub p}{sup 1.02}, for the free energy, E{sub free}∝E{sub p}{sup 1.7} and E{sub free}∝B{sub φ}{sup 1.0}L{sup 1.5}, for the dissipated energy, E{sub diss}∝E{sub p}{sup 1.6} and E{sub diss}∝E{sub free}{sup 0.9}, and the energy dissipation volume, V∝E{sub diss}{sup 1.2}. The potential energies vary in the range of E{sub p} = 1 × 10{sup 31}-4 × 10{sup 33} erg, while the free energy has a ratio of E {sub free}/E{sub p} ≈ 1%-25%. The Poynting flux amounts to F {sub flare} ≈ 5 × 10{sup 8}-10{sup 10} erg cm{sup –2} s{sup –1} during flares, which averages to F {sub AR} ≈ 6 × 10{sup 6} erg cm{sup –2} s{sup –1} during the entire observation

Electronic structure and superconductivity of fcc Cr

International Nuclear Information System (INIS)

Xu, J.; Freeman, A.J.; Jarlborg, T.; Brodsky, M.B.

1984-01-01

Results of self-consistent electronic structure calculations are reported for metastable fcc Cr metal. Unlike the case of bcc Cr which has E/sub F/ at a minimum in the density of states (DOS), the DOS at E/sub F/ in fcc Cr is at a peak making this one of the higher-DOS metals with the fcc structure (e.g., comparable with that of Ni and Pt). A calculated Stoner factor of 0.82 indicates that ferromagnetic ordering is not expected. Calculations of the electron-phonon coupling parameter lambda and superconducting transition temperature T/sub c/ were made using the rigid-ion approximation and strong-coupling theory with various estimates of the (unknown) phonon contribution. We conclude that T/sub c/'sroughly-equal2.5 K are reasonable, although they are substantially smaller than the T/sub c/roughly-equal10 K derived from measurements on Au-Cr-Au sandwiches

Reactions of radicals with lecithin bilayers

International Nuclear Information System (INIS)

Barber, D.J.W.; Thomas, J.K.

1978-01-01

The kinetics of reaction of .OH and e/sub aq/ - with lecithin bilayers have been measured. The rate for .OH + lecithin is 5.1 +- 0.9 x 10 8 M -1 sec -1 while the e/sub aq/ - + lecithin rate is very slow. When a solute such as pyrene is solubilized in the bilayer, .OH and e/sub aq/ - may react with the solute; rates of 1.65 +- 0.12 x 10 9 M -1 sec -1 and 7 x 10 7 M -1 sec -1 have been measured for reaction of .OH and e/sub aq/ - , respectively, with pyrene in lecithin. These rates are lower than those observed for similar reactions in homogeneous systems. This is explained in terms of (a) the protective effect of the bilayer, this being especially true for e/sub aq/ - which does not readily leave the aqueous phase, and (b) in terms of the restricted diffusion imposed on the reactive species by the bilayer. The kinetics in these model systems are relevant to reactions of radicals with membranes. Long-term alteration in the model membrane following .OH attack is manifested in terms of damage to the head group, increasing water penetration of the bilayer, and of cross-linking with the membrane, thereby restricting motion in the interior of the bilayer. Increased rigidity and leakiness of membranes is an expected consequence of radiation damage

Performance of algorithms that reconstruct missing transverse momentum in √(s) = 8 TeV proton-proton collisions in the ATLAS detector

Energy Technology Data Exchange (ETDEWEB)

Aad, G. [CPPM, Aix-Marseille Univ. et CNRS/IN2P3, Marseille (France); Abbott, B. [Oklahoma Univ., Norman, OK (United States). Homer L. Dodge Dept. of Physics and Astronomy; Abdallah, J. [Iowa Univ.,Iowa City, IA (United States); Collaboration: ATLAS Collaboration; and others

2017-04-15

The reconstruction and calibration algorithms used to calculate missing transverse momentum (E{sub T}{sup miss}) with the ATLAS detector exploit energy deposits in the calorimeter and tracks reconstructed in the inner detector as well as the muon spectrometer. Various strategies are used to suppress effects arising from additional proton-proton interactions, called pileup, concurrent with the hard-scatter processes. Tracking information is used to distinguish contributions from the pileup interactions using their vertex separation along the beam axis. The performance of the E{sub T}{sup miss} reconstruction algorithms, especially with respect to the amount of pileup, is evaluated using data collected in proton-proton collisions at a centre-of-mass energy of 8 TeV during 2012, and results are shown for a data sample corresponding to an integrated luminosity of 20.3 fb{sup -1}. The simulation and modelling of E{sub T}{sup miss} in events containing a Z boson decaying to two charged leptons (electrons or muons) or a W boson decaying to a charged lepton and a neutrino are compared to data. The acceptance for different event topologies, with and without high transverse momentum neutrinos, is shown for a range of threshold criteria for E{sub T}{sup miss}, and estimates of the systematic uncertainties in the E{sub T}{sup miss} measurements are presented. (orig.)

The decreased influence of overall treatment time on the response of human breast tumor xenografts following prolongation of the potential doubling time (T{sub pot})

Energy Technology Data Exchange (ETDEWEB)

Sarkaria, Jann N; Fowler, John F; Lindstrom, Mary J; Jordan, V Craig; Mulcahy, R Timothy

1995-02-15

Purpose: Repopulation during fractionated radiotherapy has been postulated to result in a significant loss in local control in rapidly proliferating tumors. Clinical data suggest that accelerated fractionation schedules can overcome the influence of repopulation by limiting the overall treatment time. Unfortunately, accelerated therapy frequently leads to increased acute reactions, which may become dose limiting. An alternative to accelerated fractionation would be to decrease the rate of repopulation during therapy. To test the potential efficacy of this alternative, we examined the effect of reducing tumor proliferation rate on the response of MCF-7 human breast carcinoma xenografts treated with a short vs. a long course of fractionated therapy. To reduce the proliferation rate, we deprived nude mice transplanted with MCF-7 xenografts of the growth-stimulating hormone estradiol (E{sub 2}). We have previously reported that E{sub 2} deprivation increases the potential doubling time (T{sub pot}) for MCF-7 xenografts from a mean of 2.6 days to 5.3 days (p < 0.001). Methods and Materials: E{sub 2}-stimulated and E{sub 2}-deprived MCF-7 breast carcinoma xenografts were clamped hypoxically and irradiated with four fractions of 5 Gy each, using either a short (3-day) or long (9-day) treatment course. E{sub 2} stimulation was restored in all animals at the completion of irradiation. Radiation response was determined by regrowth time and regrowth delay of the irradiated tumors as compared to unirradiated controls. Results: Prolongation of therapy in rapidly proliferating, E{sub 2}-stimulated tumors (T{sub pot} {approx} 2.6 days) resulted in a significant decrease in regrowth time in two identical experiments. With results pooled for analysis, the regrowth times for the short and long treatments were 62 and 32 days, respectively (combined p < 0.001). The shorter regrowth times suggest that there was less overall tumor damage with the longer fractionated radiotherapy course

Latitudinal and seasonal variations of lower atmospheric inertial gravity wave energy revealed by US radiosonde data

Energy Technology Data Exchange (ETDEWEB)

Zhang, S.D.; Yi, F. [Wuhan Univ., Hubei (China). School of Electronic Information; Ministry of Education, Wuhan, Hubei (China). Key Lab. of Geospace Environment and Geodesy; State Observatory for Atmospheric Remote Sensing, Wuhan (China); Huang, C.M. [Wuhan Univ., Hubei (China). School of Electronic Information; Ministry of Education, Wuhan, Hubei (China). Key Lab. of Geospace Environment and Geodesy; State Observatory for Atmospheric Remote Sensing, Wuhan (China); Miami Univ., Oxford, OH (United States). Electrical and Computer Engineering Dept.; Zhou, Q. [Miami Univ., Oxford, OH (United States). Electrical and Computer Engineering Dept.

2010-07-01

The latitudinal and seasonal variations of gravity wave (GW) potential energy density (E{sub P}), kinetic energy density (E{sub K}), and total energy density (E{sub T}), i.e, the sum of potential and kinetic energy densities in the tropospheric (typically 2-10 km) and lower stratospheric (typically 18- 25 km) segments have been derived from 10 years (1998- 2007) of radiosonde observations over 92 United States stations in the Northern Hemisphere. The latitudinal variation of E{sub P} in the lower stratosphere is in good agreement with satellite observations. However, E{sub K} and E{sub T} in the lower stratosphere are different from satellite observations and the difference is believed to be linked with the latitudinal dependence of GW sources. Our analysis reveals that GW energy properties exhibit distinctive latitudinal and seasonal variations. The upward-propagating GW energy in the troposphere is larger than that in the lower stratosphere at low latitudes but the opposite holds true at high latitudes. The transition latitude, where the upward- propagating energies in the two altitude regions are the same, occurs at 35 N throughout the year. So striking differences between GW activity in the troposphere and lower stratosphere are not likely explained only by the background wind Doppler shifting due to strong tropospheric jets. Our analysis indicates that the region around tropopause, roughly from 10 km to 18 km, is an important source region, especially at latitudes below 35 N. Our studies strongly suggest that in order to fully understand the global GW activity in the lower atmosphere, the GW kinetic energy and its geographical and seasonal variations should be included, and more attention should be given to GWs in the troposphere and GW sources within the intermediate region, especially the upper troposphere. (orig.)

Structural and dynamical properties of solvated electrons; a study of kinetic spectroscopy using pulse radiolysis

International Nuclear Information System (INIS)

Huis, C. van

1977-01-01

In this thesis the pulse radiolysis experiments of hexamethyl-phosphortriamide (HMPA), propanol-1, 3-methylpentane and mixtures of propanol-1 and 3-methylpentane are reported. In the pulse radiolysis of HMPA, carried out at room temperature, the high yield of esub(s) - (G=2) and the very high wavelength of the maximum absorption (max= 2200 nm) in the esub(s) - absorption spectrum are explained by considering the aprotic nature and the molecular structure of this compound. In the experiment with propanol-1 (temperature range 93deg-123degK) a temporal shift to lower wavelengths in the time range of 10 s-10 ms is observed. In further experiments biphenyl was used as electron scavenger. It was concluded that after the electron pulse the following sequence of events takes place: 1) electron redistribution in times shorter than 1 s; 2) dipole reorientation during 10 s-10 ms; 3) recombination of a part of the solvated electrons; 4) a reaction of the solvated electrons with the neighbouring propanol-1 molecules. In the experiments with 3-methylpentane at 103deg-113degK an esub(s) - absorption band with third order decay kinetics was observed. This is attributed to geminate recombination. The activation energy of the recombination process was 0.4 eV. The experiments with mixtures of propanol-1 and 3-methylpentane were carried out at 103degK. At low propanol-1 concentrations the build-up at 500 nm obeys first order kinetics, whereas at high concentrations this build-up can be split up into three first order components, as was measured in pure propanol-1. The half-lives of the three components were in the ratio of 1:10:100. In the last chapter theoretical models for the electron redistribution and the matric relaxation are discussed and compared with the experiments

Erosion Results of the MISSE 7 Polymers Experiment and Zenith Polymers Experiment After 1.5 Years of Space Exposure

Science.gov (United States)

De Groh, Kim K.; Banks, Bruce A.; Yi, Grace T.; Haloua, Athena; Imka, Emily C.; Mitchell, Gianna G.; Asmar, Olivia C.; Leneghan, Halle A.; Sechkar, Edward A.

2016-01-01

Polymers and other oxidizable materials on the exterior of spacecraft in the low Earth orbit (LEO) space environment can be eroded due to reaction with atomic oxygen (AO). Therefore, in order to design durable spacecraft it is important to know the LEO AO erosion yield (E(sub y), volume loss per incident oxygen atom) of materials susceptible to AO reaction. Two spaceflight experiments, the Polymers Experiment and the Zenith Polymers Experiment, were developed to determine the AO E(sub y) of various polymers flown in ram, wake or zenith orientations in LEO. These experiments were flown as part of the Materials International Space Station Experiment 7 (MISSE 7) mission for 1.5 years on the exterior of the International Space Station (ISS). The experiments included Kapton H(TradeMark) witness samples for AO fluence determination in ram and zenith orientations. The Polymers Experiment also included samples to determine whether AO erosion of high and low ash containing polymers is dependent on fluence. This paper provides an overview of the MISSE 7 mission, a description of the flight experiments with details on the polymers flown, the characterization techniques used, the AO fluence for each exposure orientation, and the LEO E(sub y) results. The E(sub y) values ranged from 7.99x10(exp -28)cu cm/atom for TiO2/Al2O3 coated Teflon(TradeMark) fluorinated ethylene propylene (FEP) flown in the ram orientation to 1.22x10(exp -23cu cm/atom for polyvinyl alcohol (PVOH) flown in the zenith orientation. The E(sub y) of similar samples flown in different orientations has been compared to help determine solar exposure and associated heating effects on AO erosion. The E(sub y) data from these ISS spaceflight experiments provides valuable information for LEO spacecraft design purposes.

Physical properties of N{sub x}TiO{sub 2} prepared by sol-gel route

Energy Technology Data Exchange (ETDEWEB)

Brahimi, Razika [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry, U.S.T.H.B., BP 32, 16111, El-Alia, Algiers (Algeria); Centre of Research in Physical and Chemical Analysis (CRAPC) BP 248, RP 16004, Algiers (Algeria); Bessekhouad, Yassine, E-mail: ybessekhouad@yahoo.fr [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry, U.S.T.H.B., BP 32, 16111, El-Alia, Algiers (Algeria); National Veterinary High School, BP 161-El Harrach, Algiers (Algeria); Trari, Mohamed [Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry, U.S.T.H.B., BP 32, 16111, El-Alia, Algiers (Algeria)

2012-09-15

The compounds N{sub x}TiO{sub 2}(x=0, 0.05, 0.1, 0.2) with the anatase structure have been synthesized by Sol-Gel method using Tri-ethyl Amine as nitrogen source and their optical, electrical and electrochemical properties are investigated. The electrical conductivity and thermoelectric power are measured in the temperature rang 300-600 K. The samples exhibit p-type behavior in contrast to TiO{sub 2}. The doped-samples exhibit two optical transitions (2.35{<=}E{sub h-Vis}(eV){<=}2.55; 1.97{<=}E{sub l-Vis} (eV){<=}2.06) directly allowed in the visible region, while only one transition is observed in UV region (E{sub UV}{approx}3.00 eV). Pure TiO{sub 2} shows direct band gap transition of 3.17 eV. The results confirm experimentally the calculations of Di. Valentin et al. . The transitions E{sub h-Vis} and E{sub l-Vis} are attributed respectively to the promotion of electrons from the localized N 2p and {pi}{sup Low-Asterisk} N-O bond to the conduction band. In all cases, E{sub UV} is associated to the forbidden band energy. Though that the conductivity is generally improved by doping process, only N{sub 0.05}TiO{sub 2} and N{sub 0.1}TiO{sub 2} shows an enhanced mobility. The mechanism of conduction takes place by small polaron hopping. The band edge positions of N{sub x}TiO{sub 2} (x=0, 0.05, 0.1, 0.2) at room temperature is predicted from the obtained physical properties. This study proves experimentally the principal role of nitrogen in doping process and permits the electronic states localization associated with N-impurities in TiO{sub 2} anatase.

On the relation between the ratio of energy of vaporization to activation energy for flow and physical properties of liquid metals

International Nuclear Information System (INIS)

Dutt, N.V.K.; Ravikumar, Y.V.L.; Prasad, D.H.L.

1993-01-01

A relation between the ratio of energy of vaporization (Esub(vap) to the activation energy for flow (Esub(vis)) and the ratio of melting point (T m ) to the critical temperature (T c ) has been developed for liquid metals, and is shown to be superior to the examinations from Eyring theory. (author). 12 refs

Self-consistent field with pseudowavefunctions

International Nuclear Information System (INIS)

Szasz, L.

1976-01-01

A computational method is given in which the energy of an atom is computed by using pseudowavefunctions only. The method centers on a model energy expression E/sub M/ which is similar to the Hartree--Fock energy expression, but contains only pseudowavefunctions. A theorem is proved according to which the Hartree--Fock orbitals can be transformed by a linear transformation into a set of uniquely defined pseudowavefunctions which have the property that, when substituted into E/sub M/, this quantity will closely approximate the Hartree--Fock energy E/sub F/. The new method is then formulated by identifying the total energy of an atom with the minimum of E/sub M/. Application of the energy minimum principle leads to a set of equations for the pseudowavefunctions which are similar to but simpler than the Hartree--Fock equations. These equations contain pseudopotentials for which explicit expressions are derived. The possibility of replacing these pseudopotentials by simpler model potentials is discussed, and the criteria for the selection of the model potential are outlined

Relationships between the curing conditions and some mechanical properties of hybrid thermosetting materials

Energy Technology Data Exchange (ETDEWEB)

Dias Filho, Newton L.; Aquino, Hermes A. de [UNESP, Ilha Solteira, SP (Brazil). Dept. de Fisica e Quimica]. E-mail: nldias@dfq.feis.unesp.br; Cardoso, Celso X. [UNESP, Presidente Prudente, SP (Brazil). Dept. de Fisica, Quimica e Biologia

2006-09-15

The relationship between the heat of polymerization ({alpha}H) and activation energy (E{sub a}) parameters, obtained by differential scanning calorimetry (DSC) and the ratio of epoxy resin to hardener of the thermosetting materials based on an organic-inorganic hybrid epoxy resin (OG) was investigated. Activation energy (E{sub a}) and heat of polymerization ({alpha}H) increased with an increasing OG content, up to 70 wt %. Further increase in OG content to 80 wt % reduced E{sub a} and {alpha}H. Dynamic mechanical analysis indicates that the maximum cross-link density is obtained at 83 wt % OG, whereas fracture toughness and tensile modulus mechanical properties are maximized at 70 wt % OG. (author)

Determination of deep-level impurities and their effects on the small-single and LF noise properties of ion-implanted GaAs MESFETs

International Nuclear Information System (INIS)

Sriram, S.; Kim, B.; Ghosh, P.K.; Das, M.B.; Pennsylvania State Univ., University Park; Pennsylvania State Univ., University Park

1982-01-01

A large number of deep levels, with energies ranging from Esub(c)-0.19eV to Esub(c)-0.9eV, have been identified and characterized using ion-implanted MESFET's on undoped and Cr-doped LEC-grown semi-insulating GaAs substrates. Measurement techniques used include deep level transient (DLTS) and steady state spectroscopic (DLSS) methods. Large capture cross-section values are obtained for levels below Esub(c)-0.5eV, possibly due to high electric field. Spectral densities of LF noise with distinct bulges have been shown to be related to deep levels. In some samples, natural deep level related oscillations have been observed and their ionization energies have been determined. (author)

Optical properties of PbS thin films

Energy Technology Data Exchange (ETDEWEB)

Akhmedov, O. R., E-mail: orucahmedov@mail.ru; Guseinaliyev, M. G. [National Academy of Azerbaijan, Nakhichevan Branch (Azerbaijan); Abdullaev, N. A.; Abdullaev, N. M.; Babaev, S. S.; Kasumov, N. A. [National Academy of Sciences of Azerbaijan, Abdullaev Institute of Physics (Azerbaijan)

2016-01-15

The complex dielectric function of PbS thin films is studied by spectroscopic ellipsometry in the spectral range from 0.74 to 6.45 eV at a temperature of 293 K. The critical energies are determined to be E{sub 1} = 3.53 eV and E{sub 2} = 4.57 eV. For both energy regions, the best fit is attained at the critical point 2D (m = 0). In addition, the Raman spectra and the optical-absorption spectra of PbS thin films are studied. From the dependence of the quantity (αhν){sup 2} on the photon energy hν, the band gap is established at E{sub g} = 0.37 eV.

CP-even and CP-odd transverse polarization of the electron in the muon decay

International Nuclear Information System (INIS)

Kuznetsov, A.V.

1981-01-01

In the most general weak interaction model with intermediate vector bosons, allowing CP breaking in the muon decay, CP- even and CP-odd transverse polarization of the μ-decay electrons is calculated taking into account the radiative corrections. It is shown that such corrections are essential only at the beginning of the spectrum reducing the observed transverse polarization effects. When the electron energy is close to its maximum and the emission angles are small, the transverse polarization considerably grows. Search for CP-even and CP-odd transverse polarization of the electrons should be carried out at energies Esub(e) approximately equal to O.975 Esub(e)sup(max) and emission angles THETA approximately equal to 25+35 deg [ru

Exceptional groups and elementary-particle structures

Energy Technology Data Exchange (ETDEWEB)

Biedenharn, L.C.; Truini, P.

1981-09-01

A new finite-dimensional quantum mechanical space is constructed over the complex octonionic plane using the recently developed algebraic techniques of Jordan pairs and inner ideals. The automorphism group of this structure is E/sub 6/ x U(1), realized on precisely two E/sub 6/ irreps which is abstracted as a (topless) model for grand unification.

Compactifications of the Heterotic string with unitary bundles

Energy Technology Data Exchange (ETDEWEB)

Weigand, T.

2006-05-23

In this thesis we investigate a large new class of four-dimensional supersymmetric string vacua defined as compactifications of the E{sub 8} x E{sub 8} and the SO(32) heterotic string on smooth Calabi-Yau threefolds with unitary gauge bundles and heterotic five-branes. The first part of the thesis discusses the implementation of this idea into the E{sub 8} x E{sub 8} heterotic string. After specifying a large class of group theoretic embeddings featuring unitary bundles, we analyse the effective four-dimensional N=1 supergravity upon compactification. From the gauge invariant Kaehler potential for the moduli fields we derive a modification of the Fayet-Iliopoulos D-terms arising at one-loop in string perturbation theory. From this we conjecture a one-loop deformation of the Hermitian Yang-Mills equation and introduce the idea of {lambda}-stability as the perturbatively correct stability concept generalising the notion of Mumford stability valid at tree-level. We then proceed to a definition of SO(32) heterotic vacua with unitary gauge bundles in the presence of heterotic five-branes and find agreement of the resulting spectrum with the S-dual framework of Type I/Type IIB orientifolds. A similar analysis of the effective four-dimensional supergravity is performed. Further evidence for the proposed one-loop correction to the stability condition is found by identifying the heterotic corrections as the S-dual of the perturbative part of {pi}-stability as the correct stability concept in Type IIB theory. After reviewing the construction of holomorphic stable vector bundles on elliptically fibered Calabi-Yau manifolds via spectral covers, we provide semi-realistic examples for SO(32) heterotic vacua with Pati-Salam and MSSM-like gauge sectors. We finally discuss the construction of realistic vacua with flipped SU(5) GUT and MSSM gauge group within the E{sub 8} x E{sub 8} framework, based on the embedding of line bundles into both E{sub 8} factors. Some of the appealing

Resonant excitation and the decay of autoionization states in a strong electromagnetic field

International Nuclear Information System (INIS)

Andryushin, A.I.; Kazakov, A.E.; Fedorov, M.V.

1985-01-01

Photoionization of atoms involving resonant excitation of the auto-ionization state is studied. The evolution of the total ionization probability, its dependence on the frequency of the resonance radiation and also the photoelectron energy spectrum are investigated. It is shown that the energy of the final state of the system may be localized either in the vicinity of E approximately Esub(α), where Esub(α) is the auto-ionization energy, or in the vicinity of E approximately Esub(α)+h/2πω where h/2πω is the quantum energy of the resonance radiation. The photoelectron specturum in the region E approximately Esub(α)+h/2πω as a whole is similar to the electron spectrum on photoionization of atoms involving resonance excitation of the bound state. A strong effect on the photoelectron spectrum in the region E approximately Esub(α) is exerted by interference of various decay channels of the ground state in the resonance field which leads to the appearance in the spectrum of a characteristic structure of the Fano type. Interence also affects the widths of the two spectral curves, the relatve amount of electrons in the two energy ranges and also other characteristics of the ionization process. It is shown that the presence of a noninterfering photoionization channel of the autoionization state ensures the finiteness of the swidths and heights of the spectral curves and the absence of complete ''coherency merging''

Culture of bovine ovarian follicle wall sections maintained the highly estrogenic profile under basal and chemically defined conditions

Energy Technology Data Exchange (ETDEWEB)

Vasconcelos, R.B. [Laboratório de Biotecnologia da Reprodução, Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF (Brazil); Salles, L.P. [Laboratório de Biologia Molecular, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF (Brazil); Silva, I. Oliveira e; Gulart, L.V.M. [Laboratório de Biotecnologia da Reprodução, Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF (Brazil); Souza, D.K. [Laboratório de Biotecnologia da Reprodução, Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF (Brazil); Faculdade de Ceilândia, Universidade de Brasília, Ceilândia, DF (Brazil); Torres, F.A.G. [Laboratório de Biologia Molecular, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF (Brazil); Bocca, A.L. [Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF (Brazil); Silva, A.A.M. Rosa e [Laboratório de Biotecnologia da Reprodução, Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF (Brazil)

2013-08-16

Follicle cultures reproduce in vitro the functional features observed in vivo. In a search for an ideal model, we cultured bovine antral follicle wall sections (FWS) in a serum-free defined medium (DM) known to induce 17β-estradiol (E{sub 2}) production, and in a nondefined medium (NDM) containing serum. Follicles were sectioned and cultured in NDM or DM for 24 or 48 h. Morphological features were determined by light microscopy. Gene expression of steroidogenic enzymes and follicle-stimulating hormone (FSH) receptor were determined by RT-PCR; progesterone (P{sub 4}) and E{sub 2} concentrations in the media were measured by radioimmunoassay. DM, but not NDM, maintained an FWS morphology in vitro that was similar to fresh tissue. DM also induced an increase in the expression of all steroidogenic enzymes, except FSH receptor, but NDM did not. In both DM and NDM, there was a gradual increase in P{sub 4} throughout the culture period; however, P{sub 4} concentration was significantly higher in NDM. In both media, E{sub 2} concentration was increased at 24 h, followed by a decrease at 48 h. The E{sub 2}:P{sub 4} ratio was higher in DM than in NDM. These results suggest that DM maintains morphological structure, upregulates the expression of steroidogenic enzyme genes, and maintains steroid production with a high E{sub 2}:P{sub 4} ratio in FWS cultures.

On spinor geometry: A genesis of extended supersymmetry

International Nuclear Information System (INIS)

Budini, P.

1980-08-01

It is conjectured that euclidean geometry should be derived from spinor geometry through the equivalence of simple semispinor with isotropic semi n-vectors. The only tensors of complex 2n dimensional Euclidean space Esub(c)sup(2n) should then be: isotropic n - vectors and their intersections. Esub(c) 4 spinor geometry generates two isotropic semi bivectors equivalent to the semispinors of Esub(c) 4 (their geometrical properties are those of light propagating in vacuum), and their intersection: an isotropic vector (possibly representing momenta of massless particle and/or light rays); but no scalar, pseudoscalar or pseudovector is generated. In order to generate vectors outside the light cone in Msup(3.1) one needs not less than Esub(c) 6 spinor geometry which also generates Lorentz pseudoscalars and non isotropic pseudovectors and tensors. Besides, Dirac spinor should then always appear in doublets in Msup(3.1). Furthermore the mere geometrical structure of Esub(c) 6 spinor geometry seems to suggest formally, both Poincare (extended) and conformal supersymmetry. The suggested spinor-geometrical approach privileges the elementary role of semispinors. Its relevance for the real world should be manifested by the privileged role of semispinors in elementary interactions as in fact seems to be the case with Lorentz semispinors in weak interactions (and could perhaps also be the case for strong ones where conformal semispinors (or twistors) could be the interacting spinor fields). (author)

Forbidden energy band gap in diluted a-Ge{sub 1-x}Si{sub x}:N films

Energy Technology Data Exchange (ETDEWEB)

Guarneros, C.; Rebollo-Plata, B. [Posgrado en Fisica Aplicada, Facultad de Ciencias Fisico-Matematicas, Benemerita Universidad Autonoma de Puebla, Blvd. 14 Sur 6301, Col. San Manuel, 72570, Puebla (Mexico); Lozada-Morales, R., E-mail: rlozada@fcfm.buap.mx [Posgrado en Fisica Aplicada, Facultad de Ciencias Fisico-Matematicas, Benemerita Universidad Autonoma de Puebla, Blvd. 14 Sur 6301, Col. San Manuel, 72570, Puebla (Mexico); Espinosa-Rosales, J.E. [Posgrado en Fisica Aplicada, Facultad de Ciencias Fisico-Matematicas, Benemerita Universidad Autonoma de Puebla, Blvd. 14 Sur 6301, Col. San Manuel, 72570, Puebla (Mexico); Portillo-Moreno, J. [Facultad de Ciencias Quimicas, Benemerita Universidad Autonoma de Puebla, Blvd. 14 Sur 6301, Col. San Manuel, 72570, Puebla (Mexico); Zelaya-Angel, O. [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados del IPN, PO Box 14-740, Mexico 07360 D.F. (Mexico)

2012-06-01

By means of electron gun evaporation Ge{sub 1-x}Si{sub x}:N thin films, in the entire range 0 {<=} x {<=} 1, were prepared on Si (100) and glass substrates. The initial vacuum reached was 6.6 Multiplication-Sign 10{sup -4} Pa, then a pressure of 2.7 Multiplication-Sign 10{sup -2} Pa of high purity N{sub 2} was introduced into the chamber. The deposition time was 4 min. Crucible-substrate distance was 18 cm. X-ray diffraction patterns indicate that all the films were amorphous (a-Ge{sub 1-x}Si{sub x}:N). The nitrogen concentration was of the order of 1 at% for all the films. From optical absorption spectra data and by using the Tauc method the energy band gap (E{sub g}) was calculated. The Raman spectra only reveal the presence of Si-Si, Ge-Ge, and Si-Ge bonds. Nevertheless, infrared spectra demonstrate the existence of Si-N and Ge-N bonds. The forbidden energy band gap (E{sub g}) as a function of x in the entire range 0 {<=} x {<=} 1 shows two well defined regions: 0 {<=} x {<=} 0.67 and 0.67 {<=} x {<=} 1, due to two different behaviors of the band gap, where for x > 0.67 exists an abruptly change of E{sub g}(x). In this case E{sub g}(x) versus x is different to the variation of E{sub g} in a-Ge{sub 1-x}Si{sub x} and a-Ge{sub 1-x}Si{sub x}:H. This fact can be related to the formation of Ge{sub 3}N{sub 4} and GeSi{sub 2}N{sub 4} when x {<=} 0.67, and to the formation of Si{sub 3}N{sub 4} and GeSi{sub 2}N{sub 4} for 0.67 {<=} x. - Highlights: Black-Right-Pointing-Pointer Nitrogen doped amorphous Ge{sub 1-x}Si{sub x} thin films are grown by electron gun technique. Black-Right-Pointing-Pointer Nitrogen atoms on E{sub g} of the a-Ge{sub 1-x}Si{sub x} films in the 0 Pound-Sign x Pound-Sign 1 range are analyzed. Black-Right-Pointing-Pointer Variation in 0 Pound-Sign x Pound-Sign 1 range shows a warped change of E{sub g} in 1.0 - 3.6 eV range. Black-Right-Pointing-Pointer The change in E{sub g}(x) behavior when x {approx} 0.67 was associated with Ge{sub 2}SiN{sub 4

Reaction /sup 56/Fe (. gamma. ,. cap alpha. /sub 0/) and /sup 56/Fe (. gamma. , p/sub 0/)

Energy Technology Data Exchange (ETDEWEB)

Tamae, T; Sugawara, M [Tohoku Univ., Sendai (Japan). Lab. of Nuclear Science; Tsubota, H

1975-06-01

Precise analysis was made on the cross section of the /sup 56/Fe (..gamma.., ..cap alpha../sub 0/) reaction and the angular distribution at Esub(e) = 17 MeV, including the systematic error. The (..gamma.., ..cap alpha../sub 0/) reaction cross section was compared with a calculation using the compound nucleus model, utilizing the photon absorption cross section derived from the experimental values of /sup 56/Fe (..gamma.., n) and /sup 56/Fe (..gamma.., p) cross sections. From the (..gamma.., ..cap alpha../sub 0/) reaction cross section data of various nuclei, an empirical formula was obtained for determining the position of a peak in the (..gamma.., ..cap alpha../sub 0/) reaction cross section. The /sup 56/Fe (..gamma.., p/sub 0/) reaction cross section measured at an excitation energy in the range of 14.6--25.0 MeV was compared with the calculated one with the compound nucleus model, but the form and size differ totally.

Low temperature time resolved photoluminescence in ordered and disordered Cu{sub 2}ZnSnS{sub 4} single crystals

Energy Technology Data Exchange (ETDEWEB)

Raadik, Taavi, E-mail: taavi.raadik@ttu.ee [Department of Materials Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Krustok, Jüri; Kauk-Kuusik, M.; Timmo, K.; Grossberg, M. [Department of Materials Science, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn (Estonia); Ernits, K. [crystalsol OÜ, Akadeemia tee 15a, 12618 Tallinn (Estonia); Bleuse, J. [CEA-CNRS-UGA group “Nanophysique et Semiconducteurs”, Univ. Grenoble Alpes, INAC-PHELIQS, CEA, INAC-PHELIQS, CNRS, PLUM, F-38000 Grenoble (France)

2017-03-01

In this work we performed time-resolved micro-photoluminescence (TRPL) studies of Cu{sub 2}ZnSnS{sub 4} (CZTS) single crystals grown in molten KI salt. The order/disorder degree of CZTS was varied by the thermal post treatment temperature. Photoluminescence spectra measured at T=8 K showed an asymmetric band with a peak position of 1.33 eV and 1.27 eV for partially ordered and disordered structures, respectively. Thermal activation energies were found to be E{sub T} {sub (PO)} =65±9 meV for partially ordered and E{sub T(PD)} =27±4 meV for partially disordered. These low activation energy values indicating to the defect cluster recombination model for both partially ordered and disordered structures. TRPL was measured for both crystals and their decay curves were fitted with a stretched exponential function, in order to describe the charge carriers’ recombination dynamics at low temperature.

Analytical approximations for matter effects on CP violation in the accelerator-based neutrino oscillations with E≲1 GeV

Energy Technology Data Exchange (ETDEWEB)

Xing, Zhi-zhong [Institute of High Energy Physics, Chinese Academy of Sciences,Beijing 100049 (China); School of Physical Sciences, University of Chinese Academy of Sciences,Beijing 100049 (China); Center for High Energy Physics, Peking University,Beijing 100080 (China); Zhu, Jing-yu [Institute of High Energy Physics, Chinese Academy of Sciences,Beijing 100049 (China)

2016-07-04

Given an accelerator-based neutrino experiment with the beam energy E≲1 GeV, we expand the probabilities of ν{sub μ}→ν{sub e} and ν̄{sub μ}→ν̄{sub e} oscillations in matter in terms of two small quantities Δ{sub 21}/Δ{sub 31} and A/Δ{sub 31}, where Δ{sub 21}≡m{sub 2}{sup 2}−m{sub 1}{sup 2} and Δ{sub 31}≡m{sub 3}{sup 2}−m{sub 1}{sup 2} are the neutrino mass-squared differences, and A measures the strength of terrestrial matter effects. Our analytical approximations are numerically more accurate than those made by Freund in this energy region, and thus they are particularly applicable for the study of leptonic CP violation in the low-energy MOMENT, ESSνSM and T2K oscillation experiments. As a by-product, the new analytical approximations help us to easily understand why the matter-corrected Jarlskog parameter J̃ peaks at the resonance energy E{sub ∗}≃0.14 GeV (or 0.12 GeV) for the normal (or inverted) neutrino mass hierarchy, and how the three Dirac unitarity triangles are deformed due to the terrestrial matter contamination. We also affirm that a medium-baseline neutrino oscillation experiment with the beam energy E lying in the E{sub ∗}≲E≲2E{sub ∗} range is capable of exploring leptonic CP violation with little matter-induced suppression.

Opto-electronic characterization of polycrystalline CuInS{sub 2} and Cu(In,Ga)S{sub 2} absorber layers by photoluminescence

Energy Technology Data Exchange (ETDEWEB)

Heidemann, Florian

2011-09-29

Photoluminescence (PL) is an established method to characterize the optoelectronic properties of solar cell absorber layers. With the help of Planck's generalized law it is in principle possible to determine the quasi-Fermi level splitting - which is the upper limit of the open circuit voltage V{sub oc} - and the absorption coefficient of a solar cell before its actual completion. For large-scale measurements (mm/cm regime) this is valid for absorber layers with lateral homogeneous properties, however it is not directly transferable to polycrystalline semiconductors due to laterally fluctuating opto-electronic and structural parameters. The lateral fluctuations in opto-electronic properties of polycrystalline Cu(In{sub 1-{xi}}Ga{sub {xi}})S{sub 2} have been analyzed (e.g. with respect to fluctuations in quasi-Fermi level splitting, optical band-gap and sub band-gap absorbance) by measuring laterally and spectrally resolved PL on the {mu}m-scale and providing the transition towards macroscopic PL measurements on the mm-scale. To give a comprehensive characterization, surface roughness and optical properties have been studied and methods for feature extraction have been applied. On the microscopic scale variations in the quasi-Fermi level splitting {delta}{sub x,y}E{sub Fnp} of about 38 meV (CuInS{sub 2}) and 53 meV (Cu(In,Ga)S{sub 2}) have been found. From local absorbance spectra extracted from PL measurements on Cu(In,Ga)S{sub 2} fluctuations in the optical band-gap E{sub opt} with a full width at half maximum of FWHM{sub E{sub opt}}{approx}80 meV could be extracted, whereas band-gap fluctuations in CuInS{sub 2} are found to be negligible. Thus band-gap fluctuations seem to be mainly caused by a varying gallium (Ga) content. Furthermore, regions with higher E{sub opt} and with it a potential higher Ga content, show a higher quasi-Fermi level splitting. As a major limiting factor for the local quasi-Fermi level splitting E{sub Fnp} the local density of deep

Action of. gamma. -radiation on the pH- and heat-stability of phenylalanine-tRNA-synthetases of cotton seeds

Energy Technology Data Exchange (ETDEWEB)

Karakuziev, T U [AN Uzbekskoj SSR, Tashkent. Inst. Biokhimii

1977-01-01

Action of temperature and pH on the activity of phenyl-alanine-tRNA-synthetases has been studied in two-day-old cotton seedlings grown from irradiated (25 and 50 kR) seeds. High thermolability and increased pH sensitivity were exhibited by enzymes E/sub 1/ and, particularly, E/sub 2/ of irradiated organisms as compared to those of the controls.

Radiative corrections for semileptonic decays of hyperons: the 'model independent' part

International Nuclear Information System (INIS)

Toth, K.; Szegoe, K.; Margaritis, T.

1984-04-01

The 'model independent' part of the order α radiative correction due to virtual photon exchanges and inner bremsstrahlung is studied for semileptonic decays of hyperons. Numerical results of high accuracy are given for the relative correction to the branching ratio, the electron energy spectrum and the (Esub(e),Esub(f)) Dalitz distribution in the case of four different decays. (author)

Isobaric mass systematics for A< or =60

International Nuclear Information System (INIS)

Antony, M.S.; Pape, A.

1984-01-01

The isobaric multiplet mass equation and existing spectroscopic information have been used to establish systematics for E/sub C//sup( 1 ) and E/sub C//sup( 2 ) of the nuclear Coulomb energy and extend the concept of isobaric multiplets in a coherent manner up to A = 60. Collateral information on masses of T/sub z/ = -1,-2 nuclei and radii is also presented

Formal identity of gravitational and weakly interacting recession

International Nuclear Information System (INIS)

Muheim, J.T.

1982-01-01

The author discusses the construction of models using the five elementary constants esub(s), h/2π, G, c and ksub(B) which can produce a macro or micro world with exacticity. All physical processes in nature determine the gravitational universe recession. A diagram is presented comparing the gravitational and weakly interacting recession. The Big-Bang model is discussed. (A.N.K.)

Spectroscopy of 32P. II

International Nuclear Information System (INIS)

Eijkern, F.E.H. van; Middelkoop, G. van; Sterrenburg, W.A.; Buijense, A.F.C.

1976-01-01

Spins, parities and transition probabilities of levels in 32 P at Esub(x)>3.5 MeV have been determined with the 29 Si(α, pγ) 32 P reaction at bombarding energies of Esub(α)=12.80, 12.93 and 16.30 MeV. Proton-gamma angular correlation experiments and DSA lifetime measurements lead to six unambiguous spin assignments and to many spin limitations. The measured mixing and branching ratios yield many transition strengths for dipole and electric quadrupole transitions. Five, sofar unknown, energy levels are reported. A doublet at 4.03 MeV excitation energy and a high-spin state (Esub(x)=4.27 MeV; Jsup(π)=5 - ) were observed. Shell-model predictions have been compared to the present experimental results. (Auth.)

The total kinetic energy release in the fast neutron-induced fission of {sup 232}Th

Energy Technology Data Exchange (ETDEWEB)

King, Jonathan; Yanez, Ricardo; Loveland, Walter; Barrett, J. Spencer; Oscar, Breland [Oregon State University, Dept. of Chemistry, Corvallis, OR (United States); Fotiades, Nikolaos; Tovesson, Fredrik; Young Lee, Hye [Los Alamos National Laboratory, Physics Division, Los Alamos, NM (United States)

2017-12-15

The post-emission total kinetic energy release (TKE) in the neutron-induced fission of {sup 232}Th was measured (using white spectrum neutrons from LANSCE) for neutron energies from E{sub n} = 3 to 91 MeV. In this energy range the average post-neutron total kinetic energy release decreases from 162.3 ± 0.3 at E{sub n} = 3 MeV to 154.9 ± 0.3 MeV at E{sub n} = 91 MeV. Analysis of the fission mass distributions indicates that the decrease in TKE with increasing neutron energy is a combination of increasing yields of symmetric fission (which has a lower associated TKE) and a decrease in the TKE release in asymmetric fission. (orig.)

Energy-dependent pole expansions for the effective potentials in the four-body integral equations with tensor forces

International Nuclear Information System (INIS)

Sofianos, S.; Fiedeldey, H.; Haberzettl, H.

1980-01-01

We investigate the accuracy of the energy-dependent pole expansion for the (3+1) and (2+2) subamplitudes in the calculation of the binding energy of the α particle, E/sub α/, for separable NN potentials with tensor components. We employ the truncated t-matrix (t 00 ) approximation and compare our results for E/sub α/ to those obtained, independent of any separable expansion, by Gibson and Lehman and to the results for E/sub α/ obtained with the Hilbert-Schmidt expansion of the subamplitudes. It is shown that the energy-dependent pole expansion is both more economical and converges faster than the Hilbert-Schmidt expansion, even one term of the energy-dependent pole approximation already being accurate to better than 1.5%

Spectroscopic ellipsometry study of Cu{sub 2}ZnSnSe{sub 4} bulk crystals

Energy Technology Data Exchange (ETDEWEB)

León, M., E-mail: maximo.leon@uam.es; Lopez, N.; Merino, J. M.; Caballero, R. [Department of Applied Physics M12, Universidad Autónoma de Madrid, Madrid (Spain); Levcenko, S.; Gurieva, G. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany); Serna, R. [Laser Processing Group, Instituto de Optica, CSIC, Serrano 121, 28006 Madrid (Spain); Bodnar, I. V. [Department of Chemistry, Belarusian State University of Informatics and Radioelectronics, Minsk (Belarus); Nateprov, A.; Guc, M.; Arushanov, E. [Institute of Applied Physics, Academy of Sciences of Moldova, Chisinau MD 2028 (Moldova, Republic of); Schorr, S. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany); Institute of Geological Sciences, Free University Berlin, Malteserstr. 74-100, Berlin (Germany); Perez-Rodriguez, A. [IREC, Catalonia Institute for Energy Research, C. Jardins de les Dones de Negre 1, 08930 Sant Adrià del Besòs (Barcelona) (Spain); IN2UB, Departament d' Electrònica, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona (Spain)

2014-08-11

Using spectroscopic ellipsometry we investigated and analyzed the pseudo-optical constants of Cu{sub 2}ZnSnSe{sub 4} bulk crystals, grown by the Bridgman method, over 0.8–4.5 eV photon energy range. The structures found in the spectra of the complex pseudodielectric functions were associated to E{sub 0}, E{sub 1A}, and E{sub 1B} interband transitions and were analyzed in frame of the Adachi's model. The interband transition parameters such as strength, threshold energy, and broadening were evaluated by using the simulated annealing algorithm. In addition, the pseudo-complex refractive index, extinction coefficient, absorption coefficient, and normal-incidence reflectivity were derived over 0.8–4.5 eV photon energy range.

Spectroscopy of 32P, ch. 2

International Nuclear Information System (INIS)

Eijkern, F.E.H. van; Middelkoop, G. van; Sterrenburg, W.A.; Buijense, A.F.C.

1976-01-01

Spins, parities and transition probabilities of levels in 32 P at Esub(x) 3.5 MeV have been determined with the 29 Si(α,pγ) 32 P reaction at bombarding energies of Esub(α)=12.80, 12.93 and 16.30 MeV. Proton-gamma angular correlation experiments and DSA lifetime measurements lead to six unambiguous spin assignments and to many spin limitations. The measured mixing and branching ratios yield many transition strengths for dipole and electric quadrupole transitions. Five, sofar unknown, energy levels are reported. A doublet at 4.03 MeV excitation energy and a high-spin state (Esub(x)=4.27 MeV; Jsup(π)=5 - ) were observed. Shell-model predictions have been compared to the present experimental results. (Auth.)

Magnetic field of the U-120M isochronous cyclotron

International Nuclear Information System (INIS)

Alenitskij, Yu.G.; Vasilevskaya, D.P.; Zaplatin, N.L.; Ivashkevich, S.A.; Li Zun; Morozov, N.A.; Shishlyannikov, P.T.

1976-01-01

The main results of formation and analysis of accelerator magnetic field are presented for three levels of excitation of the main electromagnet winding, Isub(0)=610,350,175A, corresponding to obtaining the maximum proton energy, Esub(k)=39.9; 30.0; 13.0 MeV on the terminal radius, r=51 cm. Distributions of currents in concentric windings are calculated, which provide acceleration of d, He 3 2 and α particles up to energies of 8,15,20 MeV; 17,40,54 MeV; 17,30,41 MeV, correspondingly. Physical starting and studies of two operation regimes (Esub(p)=40 MeV and Esub(p)=30 MeV) have shown that the magnetic field formed satisfies all the requirements for the given accelerator

Isotopic exchange kinetics of zinc ions in Zn-A zeolite

Energy Technology Data Exchange (ETDEWEB)

Radak, V M; Gal, I J; Salai, J J [Belgrade Univ. (Yugoslavia)

1976-01-01

The isotopic exchange kinetics of Zn/sup 2 +/ ions in hydrated Zn-A zeolite of composition (Znsub(5.55)Nasub(0.90)(A10/sub 2/)/sub 12/(Si0/sub 2/)/sub 12/.aq) have been investigated by measuring the fractional attainment of isotopic equilibrium between a ZnCl/sub 2/ solution and a /sup 65/Zn-labelled Zn-A zeolite (30 and 45 ..mu..m particle radii) as a function of time, in the temperature range 25 to 60/sup 0/C. The exchange mechanism is a two-step process which has been resolved, using the Brown-Sherry-Krambeck model (J.Phys.Chem.;75:3846(1971)) into diffusion in the solid particles, with Zn/sup 2 +/ diffusivity of D = 10sup(-3.97 + -0.03) exp(-Esub(D)/RT)m/sup 2/ s/sup -1/, Esub(D) = 67.1 +- 0.5 kJ molee/sup -1/, and an intracrystalline first-order exchange between bound and mobile Zn/sup 2 +/ ions in the network, with a rate constant of k/sub 2/ = 10sup(3.05 +- 0.25) exp(-Esub(k)/RT)s/sup -1/, Esub(k) = 56.5 +- 1.5 kJ mol/sup -1/.

The cosmic ray proton, helium and CNO fluxes in the 100 TeV energy region from TeV muons and EAS atmospheric Cherenkov light observations of MACRO and EAS-TOP

CERN Document Server

Aglietta, M; Ambrosio, M; Antolini, R; Antonioli, P; Arneodo, F; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bergamasco, L; Bernardini, P; Bertaina, M; Bilokon, H; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Carboni, M; Caruso, R; Castagnoli, C; Castellina, A; Cecchini, S; Cei, F; Chiarella, V; Chiarusi, T; Chiavassa, A; Choudhary, B C; Cini, G; Coutu, S; Cozzi, M; De Cataldo, G; De Marzo, C; De Mitri, I; De Vincenzi, M; Dekhissi, H; Derkaoui, J; Di Credico, A; Di Sciascio, G; Erriquez, O; Favuzzi, C; Forti, C; Fulgione, W; Fusco, P; Galeotti, P; Ghia, P L; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iacovacci, M; Iarocci, E; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kyriazopoulou, S; Lamanna, E; Lane, C; Levin, D S; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Mannocchi, G; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Morello, C; Mufson, S; Musser, J; Navarra, G; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; D'Ettorre-Piazzoli, B; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Saavedra, O; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Stamerra, A; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Togo, V; Trinchero, G C; Vakili, M; Valchierotti, S; Vallania, P; Vernetto, S; Vigorito, C; Walter, C W; Webb, R; 10.1016/j.astropartphys.2004.01.005

2004-01-01

The primary cosmic ray (CR) proton, helium and CNO fluxes in the energy range 80-300 TeV are studied at the National Gran Sasso Laboratories by means of EAS-TOP (Campo Imperatore, 2005 m a.s.l.) and MACRO (deep underground, 3100 m w.e., the surface energy threshold for a muon reaching the detector being E/sub mu //sup th/ approximately=1.3 TeV). The measurement is based on: (a) the selection of primaries based on their energy/nucleon (i.e., with energy/nucleon sufficient to produce a muon with energy larger than 1.3 TeV) and the reconstruction of the shower geometry by means of the muons recorded by MACRO in the deep underground laboratories; (b) the detection of the associated atmospheric Cherenkov light (C.l.) signals by means of the C.l. detector of EAS-TOP. The C.l. density at core distance r>100 m is directly related to the total primary energy E/sub 0/. Proton and helium ("p+He") and proton, helium and CNO ("p +He+CNO") primaries are thus selected at E/sub 0/ approximately=80 Te V, and at E/sub 0/ appro...

Radioimmunoassay of estrone, estradiol, estriol, progesterone, cortisol and prolactin in maternal venous blood and the cord blood of the newborn child

Energy Technology Data Exchange (ETDEWEB)

Fritschi, J

1980-01-01

The estrone analyses showed that E/sub 1/ levels are not sex-dependent. The Prog/E/sub 2/ ratio changed when the children were in states of exceptional stress; analogous findings were obtained in the acidose group. Due to the wide range of variations of E/sub 3/, it was found to be impossible to determine the stage of pregnancy from the E/sub 3/ level. Progesterone levels were significantly higher in the blood of the umbilical vein than in the umbilical artery. Prolactine levels of both the umbilical vein and the umbilical artery are significantly higher than in the mother's venous blood. Cortisol levels differed with the type of delivery, especially when comparing Caesareon with normal delivery. Also, differences were found between deliveries with more or less stress. There is no significant difference between E/sub 2//prog ratios measured during induced labour, immature delivery, application of analgetics; instead, cortisol levels are best correlated with the clinical criteria of birth stress, especially during the expulsion period in which stress factors are highest. Further, there is a correlation between the cortisol levels of the umbilical vein and the mother's venous-blood.

Study of stability of humic acids from soil and peat irradiated by gamma rays; Estudo da estabilidade de acidos humicos extraidos de solo e turfa, frente a radiacao ionizante gama

Energy Technology Data Exchange (ETDEWEB)

Silva, Wilson Tadeu Lopes da

1995-07-01

Humic acids samples (one deriving from a sedimentary soil and other from a peat), in aqueous media, were irradiated with gamma rays, in doses of 10, 50 and 100 kGy, in order to understand their chemical behavior after the irradiation. The material, before and after irradiation, was analyzed by Elemental Analysis, Functional Groups (carboxylic acids and phenols), UV/Vis Spectroscopy (E{sub 4}/E{sub 6} ratio), IR spectroscopy, CO{sub 2} content and Gel permeation Chromatography (GPC) ). The Elemental Analysis showed the humic acid derived from a peat had a most percentage quantity of Carbon and Hydrogen than the material from a sedimentary soil. From the UV/Vis Spectroscopy, it was observed a decrease of E{sub 4}/E{sub 6} ratio with an increase of the applied dose. The data from GPC are in agreement with this. The results showed that the molecular weight of the material increased by exposing it to a larger radiolitical dose. The peat material was less affected by the gamma radiation than the soil material. The carboxylic groups were responsible by radiochemical behavior of the material. (author)

Charge-exchange resonances and restoration of Wigner’s supersymmetry in heavy and superheavy nuclei

Energy Technology Data Exchange (ETDEWEB)

Lutostansky, Yu. S., E-mail: lutostansky@yandex.ru; Tikhonov, V. N. [National Research Center Kurchatov Institute (Russian Federation)

2016-11-15

Various facets of the question of whether Wigner’s supersymmetry [SU(4) symmetry] may be restored in heavy and superheavy nuclei are analyzed on the basis of a comparison of the results of calculations with experimental data. The energy difference between the giant Gamow–Teller resonance and the analog resonance (the difference of E{sub G} and E{sub A}) according to calculations based on the theory of finite Fermi systems is presented for the case of 33 nuclei for which experimental data are available. The calculated difference ΔE{sub G–A} of E{sub G} and E{sub A} tends to zero in heavier nuclei, showing evidence of the restoration of Wigner’s SU(4) symmetry. Also, the isotopic dependence of the Coulomb energy difference between neighboring isobaric nuclei is analyzed within the SU(4) approach for more than 400 nuclei in the mass-number range of A = 5–244. The restoration of Wigner’s SU(4) symmetry in heavy nuclei is confirmed. It is shown that the restoration of SU(4) symmetry is compatible with the possible existence of the stability island in the region of superheavy nuclei.

Direct evidence for a systematic evolution of optical band gap and local disorder in Ag, in doped Sb{sub 2}Te phase change material

Energy Technology Data Exchange (ETDEWEB)

Shukla, Krishna Dayal; Sahu, Smriti [Discipline of Electrical Engineering, Indian Institute of Technology Indore (India); Manivannan, Anbarasu [Discipline of Electrical Engineering, Indian Institute of Technology Indore (India); Metallurgical Engineering and Materials Science, Indian Institute of Technology Indore, Indore (India); Deshpande, Uday Prabhakarrao [UGC-DAE Consortium for Scientific Research, Indore (India)

2017-12-15

Rapid and reversible switching properties of Ag, In doped Sb{sub 2}Te (AIST) phase change material is widely used in re-writable optical data storage applications. We report here a systematic evolution of optical band gap (E{sub g}), local disorder (Tauc parameter, β), and Urbach energy (E{sub U}) of AIST material during amorphous to crystalline transition using in situ UV-Vis-NIR spectroscopy. Unlike GeTe-Sb{sub 2}Te{sub 3} (GST) family, AIST material is found to show unique characteristics as evidenced by the presence of direct forbidden transitions. Crystallization is accompanied by a systematic reduction in E{sub g} from 0.50 eV (as-deposited amorphous at 300 K) to 0.18 eV (crystalline at 300 K). Moreover, decrease in E{sub U} (from 272 to 212 meV) and β is also observed during increasing the temperature in the amorphous phase, revealing direct observation of enhancement of the medium-range order and distortion in short range order, respectively. These findings of optical transition would be helpful for distinguishing the unique behavior of AIST material from GST family. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

On mechanism of low-energy heavy ions scattering on a target surface with small atomic mass

Energy Technology Data Exchange (ETDEWEB)

Umarov, F.F. E-mail: farid1945@yahoo.com; Bazarbaev, N.N.; Kudryashova, L.B.; Krylov, N.M

2002-11-01

In the present work, an experimental study of low-energy (E{sub 0}=20-500 eV) heavy Cs{sup +} ions scattering on target surfaces with small atomic masses (Al, Si, Ni) has been performed for more accurate definition of mechanism of scattering and evaluation of an opportunity for use of heavy ions scattering as a tool of surface layer analysis. It is shown that the dependence of the relative energies of scattered ions versus the initial energy E/E{sub 0} (E{sub 0}) for Si (E{sub b}=4.64 eV/atom) and Ni (E{sub b}=4.43 eV/atom) approximately coincide despite the fact that the mass of Ni atom is twice as large as that of the Si atom mass. At the same time their binding energies E{sub b} are approximately equal to each other. It is found that the scattering angles of Cs{sup +} ions considerably exceed a limiting scattering angle {theta}{sub lim} in a single collision. It has been established that the scattering of low-energy heavy ions by light targets is described by a non-binary mechanism of many-particle interactions (simultaneous ion interaction with several target atoms). It has been shown that during the many-particle interactions the structure of energy spectra disappears; high relative energy of scattering ions and their dependence on energy of bombardment is observed. It has been found that the energy of scattered ions depends on binding energy, melting temperature and packing density of target atoms.

Auger recombination suppression and band alignment in GaAsBi/GaAs heterostructures

Energy Technology Data Exchange (ETDEWEB)

Hild, K.; Batool, Z.; Jin, S. R.; Hossain, N.; Marko, I. P.; Sweeney, S. J. [Advanced Technology Institute and Department of Physics, University of Surrey, Guildford, GU2 7XH (United Kingdom); Hosea, T. JC. [1 Advanced Technology Institute and Department of Physics, University of Surrey, Guildford, GU2 7XH, UK and also, Ibnu Sina Institute, Universiti Teknologi Malaysia, Johor Bahru, 81310 (Malaysia); Lu, X. [Department of Electrical and Computer Engineering, University of Victoria, Victoria BC, V8W 3P6, Canada and now VarianSemiconductor Equipment Associates, Gloucester, MA 01930 (United States); Tiedje, T. [Department of Electrical and Computer Engineering, University of Victoria, Victoria BC, V8W 3P6 (Canada)

2013-12-04

Using a combination of experimental and theoretical techniques we present the dependence of the bandgap E{sub g} and the spin orbit splitting energy Δ{sub so}, with Bi concentration in GaAsBi/GaAs samples. We find that the concentration at which Δ{sub so},> E{sub g} occurs at 9%. Both spectroscopic as well as first device results indicate a type I alignment.

D-brane physics. From weak to strong coupling

Energy Technology Data Exchange (ETDEWEB)

Vieira Lopes, Daniel Ordine

2013-01-10

In this thesis we discuss two aspects of branes relevant to high-energy phenomenology. First, we consider a single D6-brane wrapping a special Lagrangian cycle and the background space compactified in a Calabi-Yau orientifold the conditions needed to obtain a four-dimensional N=1 supersymmetric theory. We calculate the bosonic part of the effective action by performing a Kaluza-Klein reduction of the brane seven-dimensional action, and obtain the N=1 characteristic data. To discuss the moduli, we first fix the moduli from deformations of the background Calabi-Yau and study the D-brane deformation moduli space. We next allow for Calabi-Yau deformations, and show that the moduli space for complex structure deformations is corrected by the fields living on the D6-brane. We also calculate the scalar potential from D- and F-terms generated from brane and background configurations that would break the supersymmetry condition. We then, via Mirror Symmetry, relate the spectrum obtained in our work to the spectrum in Type IIB effective theory with D3- D5- and D7-branes, and we propose a Kaehler potential for the moduli space of brane deformations in Type IIB theories. In the second part of the thesis we discuss effects of brane intersections when the string coupling can become strong, and we work in the framework of F-theory. After reviewing the basics of F-theory constructions and a particular SU(5) model already discussed in the literature, we construct a model which contains a point of E{sub 8} singularity, and curves of E{sub 6} singularity. By explicitly resolving the space, we show that the resolution requires the introduction of higher dimensional fibers, and argue how we can circumvent this problem for the E{sub 6} curve, leading to the expected resolution that generate an E{sub 6} group, while at the E{sub 8} point we cannot make the resolution lead to an expected E{sub 8} structure.

Influence of composition on optical and dispersion parameters of thermally evaporated non-crystalline Cd{sub 50}S{sub 50−x}Se{sub x} thin films

Energy Technology Data Exchange (ETDEWEB)

Hassanien, A.S., E-mail: a.s.hassanien@gmail.com [Engineering Mathematics and Physics Dept., Faculty of Engineering (Shoubra), Benha University (Egypt); Physics Department, Faculty of Science and Humanities in Ad-Dawadmi, Shaqra University, 11911 (Saudi Arabia); Akl, Alaa A. [Physics Department, Faculty of Science and Humanities in Ad-Dawadmi, Shaqra University, 11911 (Saudi Arabia)

2015-11-05

Non-crystalline thin films of chalcogenide Cd{sub 50}S{sub 50−x}Se{sub x} system (30 ≤ x ≤ 50) were obtained by thermal evaporation technique onto a pre-cleaned glass substrate at a vacuum of 8.2 × 10{sup −4} Pa. The deposition rate and film thickness were kept constant at about 8 nm/s and 200 nm, respectively. Amorphous/crystalline nature and chemical composition of films have been checked using X-ray diffraction and energy dispersive X-ray spectroscopy (EDX). Optical properties of thin films were investigated and studied using the corrected transmittance, T(λ) and corrected reflectance, R(λ) measurements. Obtained data reveal that, the indirect optical energy gap (E{sub g}) was decreased from 2.21 to 1.57 eV. On the contrary, Urbach energy (band tail width), E{sub U} was found to be increased from 0.29 to 0.45 eV. This behavior is believed to be associated with the increase of Se-content instead of S-content in the thin films of Cd{sub 50}S{sub 50−x}Se{sub x} system. Chemical bond approach model, CBA was used to analyze the obtained values of E{sub g} and E{sub U}. Optical density, skin depth, extinction coefficient, refractive index and optical conductivity of chalcogenide CdSSe thin films were discussed as functions of Se-content. Using Wemple-DiDomenico single oscillator model, the refractive index dispersion and energy parameters and their dependence on Se content were studied. - Highlights: • Amorphous thin films of thickness 200 nm of Cd{sub 50}S{sub 50−x}Se{sub x} (30 ≤ x ≤ 50) have prepared. • Optical properties, indirect optical energy gap and band tail width were studied. • Chemical bond approach, CBA was used to analyze the obtained values of E{sub g} and E{sub U}. • New data of dispersion refractive index parameters were investigated and discussed.

Growth of boron doped hydrogenated nanocrystalline cubic silicon carbide (3C-SiC) films by Hot Wire-CVD

Energy Technology Data Exchange (ETDEWEB)

Pawbake, Amit [School of Energy Studies, Savitribai Phule Pune University, Pune 411 007 (India); Tata Institute of Fundamental Research, Colaba, Mumbai 400 005 (India); Mayabadi, Azam; Waykar, Ravindra; Kulkarni, Rupali; Jadhavar, Ashok [School of Energy Studies, Savitribai Phule Pune University, Pune 411 007 (India); Waman, Vaishali [Modern College of Arts, Science and Commerce, Shivajinagar, Pune 411 005 (India); Parmar, Jayesh [Tata Institute of Fundamental Research, Colaba, Mumbai 400 005 (India); Bhattacharyya, Somnath [Department of Metallurgical and Materials Engineering, IIT Madras, Chennai 600 036 (India); Ma, Yuan‐Ron [Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan (China); Devan, Rupesh; Pathan, Habib [Department of Physics, Savitribai Phule Pune University, Pune 411007 (India); Jadkar, Sandesh, E-mail: sandesh@physics.unipune.ac.in [Department of Physics, Savitribai Phule Pune University, Pune 411007 (India)

2016-04-15

Highlights: • Boron doped nc-3C-SiC films prepared by HW-CVD using SiH{sub 4}/CH{sub 4}/B{sub 2}H{sub 6}. • 3C-Si-C films have preferred orientation in (1 1 1) direction. • Introduction of boron into SiC matrix retard the crystallanity in the film structure. • Film large number of SiC nanocrystallites embedded in the a-Si matrix. • Band gap values, E{sub Tauc} and E{sub 04} (E{sub 04} > E{sub Tauc}) decreases with increase in B{sub 2}H{sub 6} flow rate. - Abstract: Boron doped nanocrystalline cubic silicon carbide (3C-SiC) films have been prepared by HW-CVD using silane (SiH{sub 4})/methane (CH{sub 4})/diborane (B{sub 2}H{sub 6}) gas mixture. The influence of boron doping on structural, optical, morphological and electrical properties have been investigated. The formation of 3C-SiC films have been confirmed by low angle XRD, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Fourier transform infra-red (FTIR) spectroscopy and high resolution-transmission electron microscopy (HR-TEM) analysis whereas effective boron doping in nc-3C-SiC have been confirmed by conductivity, charge carrier activation energy, and Hall measurements. Raman spectroscopy and HR-TEM analysis revealed that introduction of boron into the SiC matrix retards the crystallanity in the film structure. The field emission scanning electron microscopy (FE-SEM) and non contact atomic force microscopy (NC-AFM) results signify that 3C-SiC film contain well resolved, large number of silicon carbide (SiC) nanocrystallites embedded in the a-Si matrix having rms surface roughness ∼1.64 nm. Hydrogen content in doped films are found smaller than that of un-doped films. Optical band gap values, E{sub Tauc} and E{sub 04} decreases with increase in B{sub 2}H{sub 6} flow rate.

Double time-of-flight fast neutron spectrometry and study of the reaction Be{sup 9}(n,2n); Spectrometrie de neutrons rapides a double temps de vol et etude de la reaction Be{sup 9}(n,2n)

Energy Technology Data Exchange (ETDEWEB)

Gondrand, J C [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1964-10-01

The interaction between 14,5 MeV neutrons and Be{sup 9} was studied by a double time-of-flight method. The energy E{sub 1} and E{sub 2} of the (n,2n) reaction was measured (over all resolution 2 ns, flight path 1,50 m), the two neutrons being in the same plane with incident neutron and the scattering angle 30 degrees (angular resolution 3 degrees): 310 (n,2n) events were identified by electronic method (with photographic control) and by the kinematics (430 'back-ground' events, 1.3*10{sup 11} incident neutrons, one (n,2n) event per hour) corresponding principally (> 90 per cent) to the formation of resonant states between 4 particles (2 {alpha} and 2 neutrons) of the final state: Be{sup 8}(0) {sigma} {approx_equal} 170 mb, Be{sup 8*} (2,9 MeV) {sigma} {approx_equal} 165 mb, Be{sup 9*} (6,76 MeV) Be{sup 8}(0) {sigma} {approx_equal} 95 mb. (author) [French] La reaction Be{sup 9}(n,2n) a ete etudiee avec des neutrons de 14,5 MeV. On a mesure simultanement l'energie E{sub 1} et E{sub 2} par deux temps-de-vol (base-de-vol 1,50 m, resolution totale 2 ns), les deux neutrons etant dans le meme plan de diffusion et a 30 degres du neutron incident (resolution angulaire 3): 310 evenements (n,2n) ont ete identifies a l'aide de criteres electroniques (controles par methode photographique) et de criteres cinematiques (430 evenements parasites et fortuits, 1,3.10{sup 11} neutrons incidents, un evenement reel par heure) et sont principalement (> 90 pour cent) groupes en amas dans un diagramme type Dalitz (plan E{sub 1} E{sub 2}) correspondant aux etats resonnants: Be{sup 8}(0) {sigma} {approx_equal} 170 mb, Be{sup 8*} (2,9 MeV) {sigma} {approx_equal} 165 mb, Be{sup 9*} (6,76 MeV) Be{sup 8}(0) {sigma} {approx_equal} 95 mb.

Plasma resistivity measurements in the Wisconsin levitated octupole

International Nuclear Information System (INIS)

Brouchous, D.A.

1980-11-01

Resistivity measurements parallel to the magnetic field were made on gun injected plasmas ranging in density from 10 9 cm -3 to 10 1 parallelcm -3 in the Wisconsin levitated octupole with toroidal and poloidal magnetic fields. The 10 9 cm -3 plasma was collisionless with lambda/sub mfp/ > 100 mirror lengths, had T/sub e/ = 10 eV, T/sub i/ = 30 eV and was found to have anomalous resistivity scaling like eta = √T/sub e//n/sub e/ when E/sub parallel/ > E/su c/ is the Dreicer critical field. The 10 12 cm -3 plasma was collisional with lambda/sub mfp/ < mirror length, had T/sub e/ = T/sub i/ approx. = .2 eV and was found to have Spitzer resistivity when E/sub parallel/ < E/sub c/

On polymorphism of dysprosium trichloride

Energy Technology Data Exchange (ETDEWEB)

Zakiryanova, Irina D.; Khokhlov, Vladimir A.; Salyulev, Alexander B.; Korzun, Iraida V. [RAS Ural Branch, Ekaterinburg (Russian Federation). Institute of High-Temperature Electrochemistry

2015-07-01

For the first time, the structure of crystalline DyCl{sub 3} over a wide temperature range from room temperature to melting point was studied by Raman spectroscopy. The phonon modes (cm{sup -1}) of dysprosium trichloride (monoclinic crystal lattice of AlCl{sub 3} type, Z = 4, CN = 6) at room temperature are 257 (A{sub 1g}), 201 (E{sub g}), 112 (E{sub g}), 88 (A{sub 1g}), and 63 (E{sub g}). The monoclinic structure of the crystalline DyCl{sub 3} C{sub 2h}{sup 3} symmetry was found to remain constant over the studied temperature range. No polymorphic transformation in the solid state was detected. Gravimetry, calorimetry, and mass spectrometry have been used in addition to support the conclusions made on the basis of Raman spectroscopic data.

Electron cyclotron wave absorption by the fast tail generated by the dc electric field in tokamak plasmas

International Nuclear Information System (INIS)

Giruzzi, G.; Krivenski, V.; Fidone, I.; Ziebell, L.F.

1985-03-01

Wave damping near the electron gyrofrequency in a tokamak plasma with the energetic tail generated by the dc electric field is investigated. The electron tail is computed by a Fokker-Planck initial value code as a function of the relevant parameter Esub(parallel)/Esub(c)=Esub(parallel)Tsub(e)/(2πsub(e)c 3 Λ). It is shown that in most cases of physical interest strong damping of the e-mode occurs for oblique propagation. The results are of relevance for studies of ECRH in present-day tokamaks and in future reactors where a mildly relativistic electron tail is naturally present for large tsub(e). Special emphasis is therefore given to wave absorption for frequencies f significantly below the central electron gyrofrequency, and to the associated rf-driven current

Correlation of variations of charged particle fluxes in the flare on 3 November, 1973 with change of parameters of interplanetary medium according to the data of the ''Mars-7'' automatic interplanetary station and ''Prognoz-3'' artificial Earth's satellite

International Nuclear Information System (INIS)

Kuzhevskij, B.M.; Mineev, Yu.V.; Savenko, I.A.; Spir'kova, E.S.; Surova, G.M.; ShestopaloV, I.P.

1979-01-01

The experimental data on the charged particle fluxes in the flare on the 3d of November, 1973 are analyzed. The experiments were carried out at the ''Prognoz-3'' artificial Earth satellite and ''Mars-7'' automatic interplanetary station with the help of devices recorded Esub(e) >= 30 keV energy electrons, 1 <= Esub(p) <= 5 MeV energy protons and 1-150 MeV energy protons. Presented are the data on variations of the intensity of cosmic ray particles which are compared with the data on interplanetary magnetic fields. The character of proton and electron intensity variations is explained by the change of interplanetary medium parameters. It is supposed that the electron splashes and proton intensity variations recorded at the satellites are conditioned by the sign change of the interplanetary magnetic field

INTEGRAL and XMM-Newton observations of the low-luminosity and X-ray-rich burst GRB 040223

Energy Technology Data Exchange (ETDEWEB)

McGlynn, S.; Hanlon, L.; Foley, S. [College Univ., Dublin (Iran, Islamic Republic of). Department of Experimental Physics; McBreen, S. [ESTEC, Noordwijk (Netherlands). Astrophysics Mission Division, RSSD of ESA; Moran, L. [Southampton Univ., Southampton (United Kingdom). School of Physics and Astronomy; Preece, R. [Alabama Univ., Huntsville (United States); Kienlin, A. von [Max-Planck-Institut fur extraterrestrische Physik, Garching (Germany); Williams, O.R. [SCI-SDG, Noordwijk (Netherlands). Science Operation and Data Systems Division of ESA-ESTEC

2005-07-15

GRB 040223 was observed by INTEGRAL and XMM-Newton. GRB 040223 has a peak flux of (1.6{+-}0.13) x 10{sup -8} ergs cm{sup -2} s{sup -1}, a fluence of (4.4{+-}0.4) x 10{sup -7} ergs cm{sup -2} and a steep photon power law index of -2.3{+-}0.2, in the energy range 20-200 keV. The steep spectrum implies it is an X-ray-rich GRB with emission up to 200 keV and E{sub peak} < 20 keV. If E{sub peak} is < 10 keV, it would qualify as an X-ray flash with high-energy emission. The X-ray data has a spectral index {beta}{sub x} = -1.7{+-}0.2, a temporal decay of t{sup -0.75{+-}}{sup 0.25} and a large column density of 1.8 x 10{sup 22} cm{sup -2}. The luminosity-lag relationship was used to obtain a redshift z 0.1{sub -0.02}{sup +0.04}. The isotropic energy radiated in {gamma}-rays and X-ray luminosity after 10 hours are factors of 1000 and 100 less than classical GRBs. GRB 040223 is consistent with the extrapolation of the Amati relation into the region that includes XRF 030723 and XRF 020903.

Reaction and fusion cross sections for 32S on 27Al and 48Ti

International Nuclear Information System (INIS)

Porto, F.; Sambataro, S.; Kusterer, K.; Liu Ken Pao; Doukellis, G.; Harney, H.L.

1981-01-01

Elastic scattering and evaporation residues have been measured for the system 32 S + 27 Al at Esub(c)sub(.)sub(m)sub(.) = 66.4, 73.2 MeV and 32 S + 48 Ti at Esub(c)sub(.)sub(m)sub(.) = 96.0 MeV. Reaction cross sections have been obtained by use of the optical theorem and are found to be about 60% larger than the fusion cross sections. (orig.)

Growth mechanisms for spherical mixed hydroxide agglomerates prepared by co-precipitation method: A case of Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}(OH){sub 2}

Energy Technology Data Exchange (ETDEWEB)

Yang, Yue [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Xu, Shengming, E-mail: smxu@stinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Xie, Ming [The State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Precious Metals, Kunming 650106 (China); He, Yinghe, E-mail: yinghe.he@jcu.edu.au [School of Engineering and Physical Sciences, James Cook University, Douglas, Queensland 4811 (Australia); Huang, Guoyong [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Yang, Youcai [The State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Precious Metals, Kunming 650106 (China)

2015-01-15

Highlights: • Anisotropic growth of Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}(OH){sub 2} along the [0 0 1] direction was revealed. • DFT calculation results show crystal surface energies of (0 0 1) plane is highest. • A new model was proposed to explain the formation of spherical agglomerates. - Abstract: Spherical Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}(OH){sub 2} agglomerates were synthesized by the co-precipitation method in the presence of ammonia. The results show that the growth mechanism of spherical agglomerates follows three-stages, i.e. nucleation and anisotropic growth of single crystals; agglomeration of polycrystalline crystallites agglomerated by single crystal grains as primary particles to form embryonic agglomerates; formation, growth and consolidation of spherical agglomerates or particles by agglomeration of embryonic agglomerates, continued growth of individual crystals in the agglomerates and further attachment of primary particles. The first two stages are very fast while the last stage takes almost the entire process to complete. The main reason for the anisotropic growth of Ni{sub 1/3}Co{sub 1/3}Mn{sub 1/3}(OH){sub 2} crystal is that crystal surface energy of E{sub (001)}, E{sub (100)}, E{sub (101)} and E{sub (102)} is different with E{sub (001)} being the highest. The morphology of the final spherical agglomerates is explained by partial re-crystallization of contacting primary particles. The growth process of spherical agglomerates was examined by X-ray diffraction, scanning electron microscope, transmission electron microscope and calculation of crystal surface energy using density function theory.

Thermoluminescence detected in Magicicada sp. exoskeletons

International Nuclear Information System (INIS)

Fields, D.E.; Randall, R.B.; Bauman, C.E. III

1979-01-01

Thermoluminescent emission from the irradiated exoskeletons of cicada have been observed. At a heating rate of approximately 60 0 C/min. the peak light emission temperature was 183 +- 3 0 C. This effect corresponds to charge-carrier trap parameters of Esub(a) = 0.82 +- 0.04 eV and w 0 = 10sup(9.1 +- 0.5) sec -1 . Response to filtered γ radiation of 50-kV peak energy was on the order of 3.2 x 10 6 photons/R/g. Insect exoskeletons are thus potentially useful as dosimeters. (author)

Inelastic light scattering spectroscopy of semiconductor nitride nanocolumns

Energy Technology Data Exchange (ETDEWEB)

Calleja, J.M.; Lazic, S.; Sanchez-Paramo, J. [Departamento de Fisica de Materiales, Universidad Autonoma de Madrid, 28049 Madrid (Spain); Agullo-Rueda, F. [Materials Science Institute of Madrid, CSIC, 28049 Madrid (Spain); Cerutti, L.; Ristic, J.; Fernandez-Garrido, S.; Sanchez-Garcia, M.A.; Grandal, J.; Calleja, E. [ISOM and Departamento de Ingenieria Electronica, ETSIT, Universidad Politecnica de Madrid, Ciudad Universitaria, 28040 Madrid (Spain); Trampert, A.; Jahn, U. [Paul-Drude-Institut fuer Festkoerperelektronik, Hausvogteiplatz 5-7, 10117 Berlin (Germany)

2007-08-15

A review of inelastic light scattering measurements on group III-nitride nanocolumns grown by molecular beam epitaxy is presented. The nanocolumns are hexagonal, high quality single crystals with diameters in the range of 20 to 100 nm, with no traces of extended defects. GaN nanocolumns grown on bare Si substrates with both (111) and (100) orientation display narrow phonon peaks, indicating the absence of strain inhomogeneities. This opens the possibility of efficient integration of the nanocolumns as optoelectronic devices with the complementary metal oxide semiconductor technology. Measurements of the E{sub 2} phonon frequency on AlGaN nanocolumns indicate a linear dependence of the Al concentration on the Al relative flux, up to 60%. The E{sub 2} peak width increases with Al content due to phonon damping by alloy scattering. Inelastic light scattering measurements in InN nanocolumns display a coupled LO phonon-plasmon mode together with uncoupled phonons. The coupled mode is not observed in a reference compact sample. The origin of the coupled mode is attributed to spontaneous accumulation of electrons at the lateral surfaces of the nanocolumns. The presence of free electrons in the nanocolumns is confirmed by infrared reflectance measurements. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

High-spin states of 39K and 42Ca, ch. 4

International Nuclear Information System (INIS)

Eggenhuisen, H.H.; Elstrom, L.P.; Engelbertink, G.A.P.; Aarts, H.J.M.

1978-01-01

High-spin states of 39 K and 42 Ca have been investigated with the 28 Si( 16 O, αpγ) 39 K and 28 Si( 16 O, 2pγ) 42 Ca reactions at a beam energy of 45 MeV. Gamma-gamma coincidence, γ-ray angular distribution and linear polarization measurements were performed with a Ge(Li)-NaI(Tl) Compton suppression spectrometer and a three-crystal Ge(Li) Compton polarimeter. High-spin states of 39 K at Esub(x)=7.14, 7.78 and 8.03 and of 42 Ca at Esub(x)=7.75 MeV are established. Unambiguous spin-parity assignments of Jsup(π)=11/2 - , 13/2 - , 15/2 + , 15/2 - , 17/2 + and 19/2 - to the 39 K levels at Esub(x)=5.35, 5.72, 6.48, 7.14, 7.78 and 8.03 MeV and of 6 - , 7 - , 8 - , 9 - and (8,10) to the 42 Ca levels at Esub(x)=5.49, 6.15, 6.41, 6.55 and 7.37 MeV, respectively, have been obtained. Further spin-parity restrictions, lifetime limits, excitation energies, branching ratios and multipole mixing ratios are reported. Discrepancies with previous Jsup(π) assignments are discussed in detail. (Auth.)

Pituitary-ovarian hormones after low-dose endometrial afterloading irradiation

Energy Technology Data Exchange (ETDEWEB)

Groenroos, M.; Kauppila, O.; Pulkkinen, M.; Turunen, S.; Salmi, T.; Raekallio, J. (Turku Univ. (Finland). Dept. of Obstetrics and Gynecology)

1983-10-01

Low-dose endometrial after loading irradiation was used in 19 mentally retarded women for the induction of therapeutic amenorrhea. They were divided into two groups on the basis of age: 13 young patients (mean age 17 years, range 13-26 years) and six patients of middle age (mean age 42 years, range 34-44 years). In the young patients, during the 10 month follow-up period, the plasma E/sub 2/ levels did not decrease. However, the FSH concentration increased. Later on, 2-9 years after treatment, the E/sub 2/ levels were significantly higher than those of healthy postmenopausal women and did not differ from the values of healthy women in the six to seven days of the menstrual cycle. At that time the FSH and LH levels were similar to reference values in reproductive age. The E/sub 2//E/sub 1/ ratio was significantly higher than that of healthy women in the six to seven days of the cycle and that of postmenopausal women. Most of the menstrual cycles were anovulatory but some ovulatory also occurred. The testosterone concentrations did not differ from reference values. The ovaries of the middle age patients were more sensitive to irradiation than those of the younger patients. 7 refs.

Fission-product energy release for times following thermal-neutron fission of 235U between 2 and 14000 seconds

International Nuclear Information System (INIS)

Dickens, J.K.; Emery, J.F.; Love, T.A.; McConnell, J.W.; Northcutt, K.J.; Peelle, R.W.; Weaver, H.

1977-10-01

Fission-product decay energy-releases rates were measured for thermal-neutron fission of 235 U. Samples of mass 1 to 10 μg were irradiated for 1 to 100 sec by use of the fast pneumatic-tube facility at the Oak Ridge Research Reactor. The resulting beta- and gamma-ray emissions were counted for times-after-fission between 2 and 14,000 seconds. The data were obtained for beta and gamma rays separately as spectral distributions, N(E/sub γ/) vs E/sub γ/ and N(E/sub beta/) vs E/sub β/. For the gamma-ray data the spectra were obtained by using a NaI detector, while for the beta-ray data the spectra were obtained by using an NE-110 detector with an anticoincidence mantle. The raw data were unfolded to provide spectral distributions of modest resolution. These were integrated over E/sub γ/ and E/sub β/ to provide total yield and energy integrals as a function of time after fission. Results are low compared to the present 1973 ANS Decay-heat standard. A complete description of the experimental apparatus and data-reduction techniques is presented. The final integral data are given in tabular and graphical form and are compared with published data. 41 figures, 13 tables

Present situation of researches on polar ionosphere by C.C.I.R

International Nuclear Information System (INIS)

Ishikawa, Saburo

1974-01-01

Various subjects of studies made by the sixth research committee of C.C.I.R. (International Radio Consultative Committee) are reported. The C.C.I.R. has not any definite study programme and question concerning polar ionosphere, because it studies and delivers opinion on the techniques and operation of radio communication especially in developing countries. The subjects of study programme by the sixth research committee are as follows: estimation of the intensity and transmission loss of space wave electric field in a zone between 1.5 and 40 MHz, observation of the ionosphere of oblique entrance, scattering propagation of ionosphere, back scattering, fading of signal transmitted through ionosphere, transmission of space waves in the zone between 150 and 1,500 kHz, and effect of ionosphere on space communication. In addition, the following fourteen reports are cited: confirmation of prodromal phenomena of ionosphere disturbances, observation of the ionosphere of oblique entrance, remote propagation with supermode, basic information on forecast, back scattering, side scattering from the ground surface and ionosphere, Esub(s) propagation, scattering propagation, Esub(s) forecast, fading, effect of ionosphere on the transmission between the earth and space, radio noise produced in and above ionosphere, and propagation of standard broadcast wave. (Iwakiri, K.)

Magnetic resonance as a local probe for linear bands in the Weyl semimetals NbP and TaP

Energy Technology Data Exchange (ETDEWEB)

Baenitz, Michael; Yasuoka, Hiroshi; Majumder, Mayukh; Shekhar, Chandra; Yan, Binghai; Felser, Claudia; Schmidt, Marcus [MPI for Chemical Physics of Solids, Dresden (Germany)

2016-07-01

Some compensated d-electron semimetals, for example the monophosphites NbP and TaP, with non centrosymmetric structure and with sizable spin orbit coupling (SOC) form a new class of material: the Weyl semimetals (WSM). A unique linear crossing of valence- and conduction- band in a single point in reciprocal space defines the so called Weyl point where the fermion mass vanishes theoretically. In real materials the Fermi level E{sub F} does not exactly match the Weyl node and as a consequence residual very light fermions are found. Due to the SOC these Weyl fermions have a chirality (handedness) on their linear dispersive (E ∝k) bands and frequently a linear density of states (DOS) at the Fermi level E{sub F}. We use NMR as a probe for this linear d- electron bands. The shift provides the s- and d- electron contributions to the DOS at E{sub F}, whereas the spin lattice relaxation is governed by low energy excitations around E{sub F}. {sup 31}P (I = 1/2) - Fourier - transform - and {sup 95}Nb (I = 9/2) - broadline - sweep - NMR studies are performed. We investigated powder samples as well as single crystals on both systems. The angular dependence of the {sup 95}Nb- and {sup 31}P - NMR lines is discussed.

Vacancy enhancement of diffusion after quenching and during irradiation in silver-zinc alloys

International Nuclear Information System (INIS)

Schuele, W.

1980-01-01

Quenching and annealing experiments were performed on silver-zinc alloys with 8.14 and 30 at %Zn. From the changes of the electrical resistivity due to an increase of the degree of short-range order, the activation energy of self-diffusion was determined to be Qsub(SD) = 1.60 and Qsub(SD) = 1.38 eV for both alloys, respectively. For the migration energy of vacancies, a value Esub(V)sup(M) = 0.64 eV was found for the alloy with 8.14 at %Zn. Evidence is given that the vacancy migration energy Esub(V)sup(M) of the alloys with 30 at %Zn is smaller than 0.60 eV in agreement with data given by Berry and Orehotsky. The results of measurements of radiation-enhanced diffusion obtained by a Russian and a French group, are reinterpreted. It follows that the increase of the degree of order during irradiation is obtained only be vacancy enhancement of diffusion and that the migration activation energy of self-interstitials is Esub(I)sup(M) approximately 0.46 eV and Esub(I)sup(M) approximately 0.41 eV for the alloys with 8.14 and 30 at %Zn, respectively. (author)

Determination and analysis of optical constants for Ge{sub 15}Se{sub 60}Bi{sub 25} thin films

Energy Technology Data Exchange (ETDEWEB)

Atyia, H.E., E-mail: hebaelghrip@hotmail.com [Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt); Physics Department, Faculty of Applied Medical Science at Turabah, Taif University, Turabah (Saudi Arabia); Hegab, N.A. [Physics Department, Faculty of Education, Ain Shams University, Roxy, Cairo (Egypt)

2014-12-01

Thin films of Ge{sub 15}Se{sub 60}Bi{sub 25} were deposited, at room temperature, on glass substrates by thermal evaporation technique. The optical reflectance and transmittance of amorphous Ge{sub 15}Se{sub 60}Bi{sub 25} films were measured at normal incident in the wavelength range (500–2500 nm). The optical constants, the refractive index n and the absorption index k, were determined and analyzed according to different approximate methods using the transmittance measurements only and accurate method using the transmittance and reflectance measurements. Analysis of the absorption index k data reveal the values of the optical band gap E{sub g}{sup opt}, the width of tails E{sub e} and the type of transitions. Some optical parameters such as, high frequency dielectric constant ε{sub ∞}, dispersion parameters (oscillation energy E{sub s} and the dispersion energy E{sub d}), real and imaginary parts of complex dielectric constant (ε{sub 1} and ε{sub 2}) and dielectric parameters (dissipation factor tan δ, dielectric relaxation time τ, the volume and surface energy loss functions) were estimated by analyzing the refractive index n data.The relative errors for all optical parameters depending on different approximate methods were identified and discussed.

Calculations of the electronic density of states and conductivity consistent with the generalized optical theorem

International Nuclear Information System (INIS)

Oosten, A.B. van; Geertsma, W.

1985-01-01

In order to study density of states (DOS) effects on the resistivity of liquid metals and alloys we derive a set of integral equations for these quantities so that this set satisfies the generalized optical theorem. The DOS is calculated up to second order in the scattering potential using renormalized propagators. The theory is applicable to weak scattering systems, for example, alkali and alkaline earth metals and, for example, to Li-Pb alloys for compositions where the mean free path is much larger that the average interatomic distance. From our numerical results we conclude that the Ziman equation for the resistivity should be multiplied by g 2 =N 2 (Esub(F))/N 2 sub(O)(Esub(F)) where N(Esub(F)) is the DOS at the Fermi level as calculated in our model and Nsub(O)(Esub(F)) is the free electron DOS. This solves the long standing problem of whether or not one should correct the Ziman equation by an effective mass correction. Our model is only valid for alloys consisting of atoms with a small difference in electronegativity. This is clearly shown in the results for the liquid Li-Pb system. Some of the existing resistivity theories for weak and intermediate scattering are examined in the light of our calculations. (author)

A precision measurement of the inclusive ep scattering cross section at HERA

Energy Technology Data Exchange (ETDEWEB)

Aaron, F.D. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Bucharest Univ. (Romania). Faculty of Physics; Alexa, C. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Alimujiang, K. [DESY Hamburg (DE)] (and others)

2009-03-15

A measurement of the inclusive deep-inelastic neutral current e{sup +}p scattering cross section is reported in the region of four-momentum transfer squared, 12 GeV{sup 2} {<=} Q{sup 2} {<=} 150 GeV{sup 2}, and Bjorken x, 2. 10{sup -4} {<=} x {<=}0.1. The results are based on data collected by the H1 Collaboration at the ep collider HERA at positron and proton beam energies of E{sub e}=27.6 GeV and E{sub p}=920 GeV, respectively. The data are combined with previously published data, taken at E{sub p} = 820 GeV. The accuracy of the combined measurement is typically in the range of 1.3-2%. A QCD analysis at next-to-leading order is performed to determine the parton distributions in the proton based on H1 data. (orig.)

Attosecond nanotechnology: NEMS of energy storage and nanostructural transformations in materials

Energy Technology Data Exchange (ETDEWEB)

Beznosyuk, Sergey A., E-mail: bsa1953@mail.ru; Maslova, Olga A., E-mail: maslova-o.a@mail.ru [Altai State University, Barnaul, 656049 (Russian Federation); Zhukovsky, Mark S., E-mail: zhukovsky@list.ru [Altai State Technical University, Barnaul, 656038 (Russian Federation)

2015-10-27

The attosecond technology of the nanoelectromechanical system (NEMS) energy storage as active center fast transformation of nanostructures in materials is considered. The self-organizing relaxation of the NEMS active center containing nanocube of 256-atoms limited by planes (100) in the FCC lattice matrix of 4d-transition metals (Ru, Rh, Pd) is described by the quantum NEMS-kinetics (NK) method. Typical for these metals change of the NEMS active center physicochemical characteristics during the time of relaxation is presented. There are three types of intermediate quasistationary states of the NEMS active center. Their forms are plainly distinguishable. The full relaxed NEMS active centers (Ru{sub 256}, Rh{sub 256}, Pd{sub 256}) accumulate next storage energies: E{sub Ru} = 2.27 eV/at, E{sub Rh} = 1.67 eV/at, E{sub Pd} = 3.02 eV/at.

Observation of very large transverse momentum jets at the CERN pp collider

CERN Document Server

Banner, M; Bonaudi, Franco; Borer, K; Borghini, M; Chollet, J C; Clark, A G; Conta, C; Darriulat, Pierre; Di Lella, L; Dines-Hansen, J; Dorsaz, P A; Fayard, L; Fraternali, M; Froidevaux, D; Gaillard, J M; Gildemeister, O; Goggi, V G; Grote, H; Hahn, B; Hänni, H; Hansen, J R; Hansen, P; Himel, T; Hungerbühler, V; Jenni, Peter; Kofoed-Hansen, Otto Møgens; Livan, M; Loucatos, Sotirios S; Madsen, B; Mansoulié, B; Mantovani, G C; Mapelli, L; Merkel, B; Mermikides, Michael E; Møllerud, R; Nilsson, B; Onions, Christopher J; Parrour, G; Pastore, F; Plothow-Besch, H; Repellin, J P; Ringel, J; Rothenberg, A F; Roussarie, A; Sauvage, G; Schacher, J; Siegrist, J L; Stocker, F; Teiger, J; Vercesi, V; Williams, H H; Zaccone, Henri; Zeller, W

1982-01-01

The distribution of total transverse energy Sigma E/sub T/ over the pseudorapidity interval -1( eta (1 and an azimuthal range Delta phi =300 degrees has been measured in the UA2 experiment at the CERN pp collider ( \\sqrt{s}=540 GeV) using a highly segmented total absorption calorimeter. In the events with the very large Sigma E/sub T/ ( Sigma E/sub T/>or approximately=60 GeV) most of the transverse energy is found to be contained in small angular regions as expected for high transverse momentum hadron jets. The authors discuss the properties of a sample of two-jet events with invariant two-jet masses up to 140 GeV/c/sup 2/ and measure the cross section for inclusive jet production in the range of jet transverse momenta between 15 and 60 Ge V/c.

Transfer of 6Li break-up fragments at 6Li projectile energies far above the coulomb barrier

International Nuclear Information System (INIS)

Neumann, B.; Buschmann, J.; Rebel, H.; Gils, H.J.; Klewe-Nebenius, H.

1979-05-01

Transfer of beam-velocity fragments has been experimentally investigated in 6 Li induced reactions on 208 Pb and 209 Bi in the energy range Esub(Li) = 60-156 MeV. The experimental techniques involve the observation of the target residues and measurements of the recoil ranges of heavy residual nuclei produced by charged particle bombardment. The determination of the recoil energy enables the discrimination of different reaction paths leading to the same residual nuclei. ( 6 Li, xn+p) excitation functions prove to be very similar to (α,(x-1)n) reactions at Esub(α) approximately 2/3 x Esub(Li). The results present experimental evidence for a particular reaction type indicated in previous experiments: Dissociation of the 6 Li projectile with capture of the beam-velocity alpha particle indicating an (α,xn) reaction ('internal break-up'). (orig.) [de

Tensor analyzing powers in deuteron--proton elastic scattering and the breakup reaction at 45.4 MeV

International Nuclear Information System (INIS)

Conzett, H.E.

1978-08-01

Recently the tensor analyzing powers in vector d + p elastic scattering and in the breakup reaction at E/sub d/ = 45.4 MeV were measured. The elastic results now establish a rather complete set of polarization data in nucleon--deuteron scattering at E/sub N/ = 22.7 MeV, which consists of the proton analyzing power, the deuteron vector and tensor analyzing powers, and vector polarization transfer measurements, as well. 8 references

Confusing the heterotic string

Energy Technology Data Exchange (ETDEWEB)

Benett, D.L.; Brene, N.; Nielsen, H.B.; Mizrachi, L.

1986-10-02

A confusion mechanism is proposed as a global modification of the heterotic string model. It envolves a confusion hypersurface across which the two E/sub 8/'s of the heterotic string are permuted. A remarkable numerical coincidence is found which prevents an inconsistency in the model. The low energy limit of this theory (after compactification) is typically invariant under one E/sub 8/ only, thereby removing the shadow world from the original model.

Temperature-dependent photoluminescence analysis of 1-MeV electron irradiation-induced nonradiative recombination centers in GaAs/Ge space solar cells

Energy Technology Data Exchange (ETDEWEB)

Tiancheng, Yi; Pengfei, Xiao; Yong, Zheng; Juan, Tang; Rong, Wang, E-mail: wangr@bnu.edu.cn

2016-03-01

The effects of irradiation of 1-MeV electrons on p{sup +}–n GaAs/Ge solar cells have been investigated by temperature-dependent photoluminescence (PL) measurements in the temperature range of 10–290 K. The temperature dependence of the PL peak energy agrees well with the Varnish relation, and the thermal quenching of the total integrated PL intensity is well explained by the thermal quenching theory. Meanwhile, the thermal quenching of temperature-dependent PL confirmed that there are two nonradiative recombination centers in the solar cells, and the thermal activation energies of these centers are determined by Arrhenius plots of the total integrated PL intensity. Furthermore, the nonradiative recombination center, as a primary defect, is identified as the H3 hole trap located at E{sub v} + 0.71 eV at room temperature and the H2 hole trap located at E{sub v} + 0.41 eV in the temperature range of 100–200 K, by comparing the thermal activation and ionization energies of the defects.

Solvated electrons at elevated temperatures in different alcohols: Temperature and molecular structure effects

Energy Technology Data Exchange (ETDEWEB)

Yan, Yu [Department of Nuclear Engineering and Management, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Lin, Mingzhang [Nuclear Science and Engineering Directorate, Japan Atomic Energy Agency, 2-4 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1195 (Japan); Katsumura, Yosuke, E-mail: katsu@n.t.u-tokyo.ac.j [Department of Nuclear Engineering and Management, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Nuclear Professional School, Graduate School of Engineering, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan); Fu, Haiying; Muroya, Yusa [Nuclear Professional School, Graduate School of Engineering, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Naka, Ibaraki 319-1188 (Japan)

2010-12-15

The absorption spectra of solvated electrons in pentanol, hexanol and octanol are measured from 22 to 200, 22 to 175 and 50 to150 {sup o}C, respectively, at a fixed pressure of 15 MPa, using nanosecond pulse radiolysis technique. The results show that the peak positions of the absorption spectra have a red-shift (shift to longer wavelengths) as temperature increases, similar to water and other alcohols. Including the above mentioned data, a compilation of currently available experimental data on the energy of absorption maximum (E{sub max}) of solvated electrons changed with temperature in monohydric alcohols, diols and triol is presented. E{sub max} of solvated electron is larger in those alcohols that have more OH groups at all the temperatures. The molecular structure effect, including OH numbers, OH position and carbon chain length, is investigated. For the primary alcohols with same OH group number and position, the temperature coefficient increases with increase in chain length. For the alcohols with same chain length and OH numbers, temperature coefficient is larger for the symmetric alcohols than the asymmetric ones.

Study of giant multipole resonances in 40Ca

International Nuclear Information System (INIS)

Rost, H.

1979-01-01

In the present thesis giant resonance states in 40 Ca were studied by scattering of 104 MeV a particles on 40 Ca and by the reactions 39 K(p vector,p') 39 K and 39 K(p,α) 36 Ar. The scattered α-particles were measured at extreme forward angles (THETAsub(L) = 4 0 -16 0 C), because at forward angles the cross sections for the excitation of states with spin 0 and 1 strongly differ from those with higher spin. The aim of this experiment was first of all the study of the giant resonance region in 40 Ca on the contribution to 0 + or 1 - states. Beside the known electric giant quadrupole resonances at Esub(x) approx. equal to 18.5 MeV (25% EWSR) contributions of EO-strength at Esub(x) approx. equal to 21 MeV (6% EWSR) and indications to a (isoscalar) E1-strength at Esub(x) approx. equal to 14 MeV and Esub(x) approx. equal to 16 MeV were found. At the reactions 39 K(p vector,p') 39 K and 39 K(p,α) 36 Ar in the channels (p,p 0 ),(p,p 4 ), (p,αsub(o)), and (p,α 1 ) at incident energies at about 10 MeV (Esub(x)( 40 Ca) approx. equal to 18 MeV) resonant structures were observed. A scattering phase analysis performed for the elastic proton scattering didn't however yield quantitative results about the resonance parameter. An expansion of the cross sections by Legendre polynomials for the remaining reaction channel didn't allow a conclusion about the dominance of a certain L-value. The only indication to the connection of the observed resonant structures with the giant quadrupole resonance in 40 Ca is therefore the energetic position at about Esub(x) approx. equal to 18 MeV. Altogether the observed structures however were not very pronounced, so it can be concluded, that the excitation of the giant quadrupole resonance in 40 Ca by protons via the ground state of 39 K occurs not very strongly. (orig./HSI) [de

{sup 235}U(n,F) prompt fission neutron spectra

Energy Technology Data Exchange (ETDEWEB)

Maslov, M.V.; Tetereva, N.A. [Joint Institute of Nuclear and Energy Research, Minsk-Sosny (Belarus); Pronyaev, V.P.; Kagalenko, A.B. [Institute of Physics and Power Engineering, Obninsk (Russian Federation); Capote, R. [International Atomic Energy Agency, Vienna (Austria); Granier, T.; Morillon, B. [CEA, Centre DAM-IIe de France, 91 - Arpajon (France); Hambsch, F.J. [EC-JRC Institute for Reference Materials and Measurements, Geel (Belgium); Sublet, J.C. [CEA Cadarache, 13 - Saint Paul lez Durance (France)

2009-07-01

The longstanding problem of inconsistency of integral thermal data testing and differential prompt fission neutron spectra data (PFNS) is mostly due to rather poor fits of differential PFNS data in major data libraries. The measured database is updated by using modern standards including Manhart's evaluation of the spontaneous fission neutron spectra of {sup 252}Cf(sf). That largely removes the inconsistency of older thermal neutron-induced PFNS measurements with newest data of JRC IRMM by Hambsch et al. (2009). A phenomenological approach, developed by Kornilov et al. (1999), for the first-chance fission and extended for the emissive fission domain by Maslov et al. (2005) is calibrated at E{sub th} to predict both the PFNS average energy and PFNS shape up to 20 MeV. The latter is extremely important, since rather close values in fact correspond to quite discrepant spectra shapes, which influences reactor neutronics strongly. The proposed phenomenological representation of the PFNS reproduces both soft and hard energy tails of {sup 235}U(n{sub th},F) PFNS at thermal incident neutron energy E{sub th}. In the first-chance and emissive fission domain evaluated PFNS are consistent with the data by Ethvignot et al. (2005). A compiled MF=5 Endf/B-formatted file of the {sup 235}U(n,F) PFNS largely removes the inconsistencies of the evaluated differential PFNS with integral data benchmarks. Almost perfect fits are attained for available differential PFNS data from E{sub th} up to E{sub n}=14.7 MeV, with few exceptions at E{sub n}=2.9 and E{sub n}=5 MeV. Fast integral critical experiment like GODIVA or Flattop benchmarks might be reproduced almost with the same accuracy as with the PFNS of the major data libraries. That reveals a rather delicate compensation effect, since present and previous PFNS shapes are drastically different from each other. Thermal assemblies benchmarking reveals positive biases in k(eff), which might be attributed to the influence of

Measurement of the inclusive e{sup {+-}}p scattering cross section at high inelasticity y and of the structure function F{sub L}

Energy Technology Data Exchange (ETDEWEB)

Aaron, F.D. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Bucharest Univ. (Romania). Faculty of Physics; Alexa, C. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Andreev, V. [Lebedev Physical Institute, Moscow (RU)] (and others)

2010-12-15

A measurement is presented of the inclusive neutral current e{sup {+-}}p scattering cross section using data collected by the H1 experiment at HERA during the years 2003 to 2007 with proton beam energies E{sub p} of 920, 575, and 460 GeV. The kinematic range of the measurement covers low absolute four-momentum transfers squared, 1.5 GeV{sup 2} < Q{sup 2} < 120 GeV{sup 2}, small values of Bjorken x, 2.9 . 10{sup -5} < x < 0.01, and extends to high inelasticity up to y=0.85. The structure function FL is measured by combining the new results with previously published H1 data at E{sub p} = 920 GeV and E{sub p} = 820 GeV. The new measurements are used to test several phenomenological and QCD models applicable in this low Q{sup 2} and low x kinematic domain. (orig.)

On the generalized eigenvalue method for energies and matrix elements in lattice field theory

Energy Technology Data Exchange (ETDEWEB)

Blossier, Benoit [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)]|[Paris-XI Univ., 91 - Orsay (France). Lab. de Physique Theorique; Morte, Michele della [CERN, Geneva (Switzerland). Physics Dept.]|[Mainz Univ. (Germany). Inst. fuer Kernphysik; Hippel, Georg von; Sommer, Rainer [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Mendes, Tereza [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)]|[Sao Paulo Univ. (Brazil). IFSC

2009-02-15

We discuss the generalized eigenvalue problem for computing energies and matrix elements in lattice gauge theory, including effective theories such as HQET. It is analyzed how the extracted effective energies and matrix elements converge when the time separations are made large. This suggests a particularly efficient application of the method for which we can prove that corrections vanish asymptotically as exp(-(E{sub N+1}-E{sub n}) t). The gap E{sub N+1}-E{sub n} can be made large by increasing the number N of interpolating fields in the correlation matrix. We also show how excited state matrix elements can be extracted such that contaminations from all other states disappear exponentially in time. As a demonstration we present numerical results for the extraction of ground state and excited B-meson masses and decay constants in static approximation and to order 1/m{sub b} in HQET. (orig.)

The semi-empirical tight-binding model for carbon allotropes “between diamond and graphite”

Energy Technology Data Exchange (ETDEWEB)

Lytovchenko, V.; Kurchak, A.; Strikha, M., E-mail: maksym-strikha@hotmail.com [Institute of Semiconductor Physics, NAS of Ukraine, Pr. Nauky 41, Kyiv 03028 (Ukraine)

2014-06-28

The new carbon allotropes “between diamond and graphite” have come under intensive examination during the last decade due to their numerous technical applications. The modification of energy gap in thin films of these allotropes was studied experimentally using optical methods. The proposed simple model of carbon clusters with variable lengths of chemical bonds allows us to imitate the transfer from diamond and diamond-like to graphite-like structures, as well as the corresponding modification of hybridization sp{sup 3}/sp{sup 2} for diamond-like and sp{sub z} for graphite-like phases. This enables us to estimate various allotropes parameters, like the gap E{sub g}, energies of valence E{sub v}, and conduction E{sub c} band edges, and the value of electronic affinity, i.e., optical work function X, which are all of practical importance. The obtained estimations correspond to the experimental data.

Hormonal monitoring of early pregnancy by a direct radioimmunoassay of steroid glucuronides in first morning urine

Energy Technology Data Exchange (ETDEWEB)

Mendizabal, A.F.; Quiroga, S.; Farinati, Z.; Lahoz, M.; Nagle, C.

1984-11-01

The usefulness of the direct 4-hour radioimmunoassay of estriol-16-glucuronide (E/sub 3/G) and pregnanediol-3-glucuronide (P/sub 2/G) in first morning urine (FMU) for establishing a prognosis of the early pregnancy outcome was evaluated in 106 patients that became pregnant. Microaliquots of FMU were serially assayed from day 3 of the conception cycle until day 80 of pregnancy. The E/sub 3/G and P/sub 2/G profiles of 19 pregnancies which terminated in spontaneous abortion with either a diagnosis of the blighted ovum syndrome (n = 11) or presumption of a corpus luteum/trophoblast failure (n = 8) have been compared with those of clinically normal pregnancies (n = 87). Normal pregnancies displayed typical patterns of E/sub 3/G and P/sub 2/G development, while variations were observed in abortive events that reflected changes of the fetoplacental unit.

Update of neutron dose yields as a function of energy for protons and deuterons incident on beryllium targets

International Nuclear Information System (INIS)

Ten Haken, R.K.; Awschalom, M.; Rosenberg, I.

1982-11-01

Neutron absorbed dose yields (absorbed dose rates per unit incident current on targets at a given SAD or SSD) increase with incident charged particle energy for both protons and deuterons. Analyses of neutron dose yield versus incident particle energy have been performed for both deuterons and protons. It is the purpose of this report to update those analyses by pooling all of the more recent published results and to reanalyze the trend of yield, Y, versus incident energy, E, which in the past has been described by an expression of the form Y = aE/sup b/, where a and b are empirical constants. From the reanalyzed trend it is concluded that for a given size cyclotron (E/sub p/ = 2E/sub d/), the dose yields using protons are higher than those using deuterons up to a proton energy E/sub p/ of 64 MeV

Maximum neutron yeidls in experimental fusion devices

International Nuclear Information System (INIS)

Jassby, D.L.

1979-02-01

The optimal performances of 12 types of fusion devices are compared with regard to neutron production rate, neutrons per pulse, and fusion energy multiplication, Q/sub p/ (converted to the equivalent value in D-T operation). The record values in all categories are held by the beam-injected tokamak plasma, followed by other beam-target systems. The achieved values of Q/sub p/ for nearly all laboratory plasma fusion devices (magnetically or inertially confined) are found to roughly satisfy a common empirical scaling, Q/sub p/ approx. 10 -6 E/sub in//sup 3/2/, where E/sub in/ is the energy (in kilojoules) injected into the plasma during one or two energy confinement times, or the total energy delivered to the target for inertially confined systems. Fusion energy break-even (Q/sub p/ = 1) in any system apparently requires E/sub in/ approx. 10,000 kJ

Strain control of Urbach energy in Cr-doped PrFeO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Kumar, Anil; Warshi, M.K.; Mishra, Vikash; Saxena, Shailendra K.; Kumar, Rajesh; Sagdeo, Pankaj R. [Indian Institute of Technology Indore, Material Research Laboratory, Discipline of Physics and MEMS, Indore (India)

2017-09-15

Polycrystalline samples of PrFe{sub 1-x}Cr{sub x}O{sub 3} having average particle size of ∝90 nm have been prepared by wet chemical route. The structural phase purity of the prepared samples is confirmed by powder X-ray diffraction followed by Rietveld refinements. It is observed that with Cr doping, the Urbach energy (E{sub u}) increases. The E{sub u} is measure of the various disorders present in the sample, such as chemical and structural. To understand the contribution to the E{sub u} due to chemical and structural disorders, we have probed the chemical and structural disorders in the samples by elemental mappings and through X-ray diffraction experiments, respectively. Elemental mapping confirms chemical homogeneity of prepared samples. It is observed that with Cr doping the crystallographic strain increases and Urbach energy shows the similar scaling. (orig.)

Analysis of Return and Forward Links from STARS' Flight Demonstration 1

Science.gov (United States)

Gering, James A.

2003-01-01

Space-based Telemetry And Range Safety (STARS) is a Kennedy Space Center (KSC) led proof-of-concept demonstration, which utilizes NASA's space network of Tracking and Data Relay Satellites (TDRS) as a pathway for launch and mission related information streams. Flight Demonstration 1 concluded on July 15,2003 with the seventh flight of a Low Power Transmitter (LPT) a Command and Data Handler (C&DH), a twelve channel GPS receiver and associated power supplies and amplifiers. The equipment flew on NASA's F-I5 aircraft at the Dryden Flight Research Center located at Edwards Air Force Base in California. During this NASA-ASEE Faculty Fellowship, the author participated in the collection and analysis of data from the seven flights comprising Flight Demonstration 1. Specifically, the author examined the forward and return links bit energy E(sub B) (in Watt-seconds) divided by the ambient radio frequency noise N(sub 0) (in Watts / Hertz). E(sub b)/N(sub 0) is commonly thought of as a signal-to-noise parameter, which characterizes a particular received radio frequency (RF) link. Outputs from the data analysis include the construction of time lines for all flights, production of graphs of range safety values for all seven flights, histograms of range safety E(sub b)/N(sub 0) values in five dB increments, calculation of associated averages and standard deviations, production of graphs of range user E(sub b)/N(sub 0) values for the all flights, production of graphs of AGC's and E(sub b)/N(sub 0) estimates for flight 1, recorded onboard, transmitted directly to the launch head and transmitted through TDRS. The data and graphs are being used to draw conclusions related to a lower than expected signal strength seen in the range safety return link.

DYNAMIC STABILITY OF THE SOLAR SYSTEM: STATISTICALLY INCONCLUSIVE RESULTS FROM ENSEMBLE INTEGRATIONS

Energy Technology Data Exchange (ETDEWEB)

Zeebe, Richard E., E-mail: zeebe@soest.hawaii.edu [School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, 1000 Pope Road, MSB 629, Honolulu, HI 96822 (United States)

2015-01-01

Due to the chaotic nature of the solar system, the question of its long-term stability can only be answered in a statistical sense, for instance, based on numerical ensemble integrations of nearby orbits. Destabilization of the inner planets, leading to close encounters and/or collisions can be initiated through a large increase in Mercury's eccentricity, with a currently assumed likelihood of ∼1%. However, little is known at present about the robustness of this number. Here I report ensemble integrations of the full equations of motion of the eight planets and Pluto over 5 Gyr, including contributions from general relativity. The results show that different numerical algorithms lead to statistically different results for the evolution of Mercury's eccentricity (e{sub M}). For instance, starting at present initial conditions (e{sub M}≃0.21), Mercury's maximum eccentricity achieved over 5 Gyr is, on average, significantly higher in symplectic ensemble integrations using heliocentric rather than Jacobi coordinates and stricter error control. In contrast, starting at a possible future configuration (e{sub M}≃0.53), Mercury's maximum eccentricity achieved over the subsequent 500 Myr is, on average, significantly lower using heliocentric rather than Jacobi coordinates. For example, the probability for e{sub M} to increase beyond 0.53 over 500 Myr is >90% (Jacobi) versus only 40%-55% (heliocentric). This poses a dilemma because the physical evolution of the real system—and its probabilistic behavior—cannot depend on the coordinate system or the numerical algorithm chosen to describe it. Some tests of the numerical algorithms suggest that symplectic integrators using heliocentric coordinates underestimate the odds for destabilization of Mercury's orbit at high initial e{sub M}.

Heavy metal removal using nanoscale zero-valent iron (nZVI): Theory and application

Energy Technology Data Exchange (ETDEWEB)

Li, Shaolin, E-mail: lishaolin@tongji.edu.cn; Wang, Wei; Liang, Feipeng; Zhang, Wei-xian, E-mail: zhangwx@tongji.edu.cn

2017-01-15

Highlights: • nZVI is able to perform fast and simultaneous removal of different heavy metal ions. • Fast separation and seeding effect of nZVI facilities its application in wastewater. • A novel process of E{sub h}-controlled reactor, nZVI separator and reuse is proposed. • E{sub h}-controlled system and nZVI recirculation increase material efficiency of nZVI. • The process produces stable effluent and is effective in wastewater treatment. - Abstract: Treatment of wastewater containing heavy metals requires considerations on simultaneous removal of different ions, system reliability and quick separation of reaction products. In this work, we demonstrate that nanoscale zero-valent iron (nZVI) is an ideal reagent for removing heavy metals from wastewater. Batch experiments show that nZVI is able to perform simultaneous removal of different heavy metals and arsenic; reactive nZVI in uniform dispersion brings rapid changes in solution E{sub h}, enabling a facile way for reaction regulation. Microscope characterizations and settling experiments suggest that nZVI serves as solid seeds that facilitate products separation. A treatment process consisting of E{sub h}-controlled nZVI reaction, gravitational separation and nZVI recirculation is then demonstrated. Long-term (>12 months) operation shows that the process achieves >99.5% removal of As, Cu and a number of other toxic elements. The E{sub h}-controlled reaction system sustains a highly-reducing condition in reactor and reduces nZVI dosage. The process produces effluent of stable quality that meets local discharge guidelines. The gravitational separator shows high efficacy of nZVI recovery and the recirculation improves nZVI material efficiency, resulting in extraordinarily high removal capacities ((245 mg As + 226 mg-Cu)/g-nZVI). The work provides proof that nanomaterials can offer truly green and cost-effective solutions for wastewater treatment.

Proton threshold states in 26Al and their role in astrophysics

International Nuclear Information System (INIS)

Wijekumar, V.

1985-01-01

The energy levels of 26 Al between E/sub x/ = 6.3 and 6.5 MeV, corresponding to proton threshold energies in the 25 Mg + p reaction from E/sub p/ = 0 to 200 keV, have been investigated using the reactions 27 Al( 3 He,α) 26 Al and 24 Mg( 3 He,p) 26 Al. Despite early work reporting a doublet at E/sub x/ 6346 keV and E/sub x/ = 6362 keV, most subsequent work reported a single state with conflicting spin and parity assignments. By measuring the spectroscopic factors of these states from the 25 Mg( 3 He,d) 26 Al reaction, resonance strengths, omegaγ, of the proton threshold states in 26 Al corresponding to the 25 Mg(p,γ) 26 Al reaction have been deduced. The limits on the branching ratios from these states to the ground state of 26 Al have been obtained by using the reaction 27 Al( 3 He,αγ) 26 Al. Finally by combining the results of the above experiments, stellar reaction rates of the 25 Mg(p,γ) 26 Al reaction have been calculated. The results conclude that the production rate of 26 Al in stellar environments from the reaction 25 Mg(p,γ) 26 Al is substantially higher than what was calculated from other work

Testing two novel stump-lifting heads in a final felling Norway spruce stand

Energy Technology Data Exchange (ETDEWEB)

Kaerhae, K. (Metsaeteho Oy, Helsinki (Finland)), Email: kalle.karha@metsateho.fi; Mutikainen, A. (TTS Research, Rajamaeki (Finland)), Email: arto.mutikainen@tts.fi

2009-07-01

The use of stump and root wood chips has increased very rapidly in the 21st century in Finland: in the year 2000, the total consumption of stump wood chips for energy generation was 10 GWh, while in 2008 it was around 1.2 TWh. Metsaeteho Oy and TTS Research tested two new stump-lifting devices for lifting stumps in a final felling Norway spruce (picea abies) stand. In the time study with the Vaekevae Stump Processor lifting head, the productivity of stump lifting was 7,5 m3 / E{sub 0}-hour when lifting spruce stumps with a diameter of 30 cm from clayey soil, and 8.3 m3 /E{sub 0}-hour when lifting spruce stumps from sandy soil. When lifting stumps with a diameter of 40 cm, the stump-lifting productivity was 9.0 m3 /E{sub 0}-h (clay) and 10,5 m3 / E{sub 0}-h (sand). The results of this relatively restricted test indicated that the Vaekevae Stump Processor is s reliable and effective stump-lifting head that enables the harvesting of high-quality stump raw material for energy generation. The stump lifting productivity of the other lifting head (Jaervinen) was lower than that of the Vaekevae Strump Processor. Some development suggestions for the Jaervinen lifting head were presented and discussed. (orig.)

Lion roars and nonoscillatory drift mirror waves in the magnetosheath

International Nuclear Information System (INIS)

Tsurutani, B.T.; Smith, E.J.; Anderson, R.R.; Ogilvie, K.W.; Scudder, J.D.; Baker, D.N.; Bame, S.J.

1982-01-01

A complete set of ISEE plasma wave, plasma, and field data are used to identify the plasma instability responsible for the generation of extremely low frequency (ELF) electromagnetic lion roars. Lion roars detected close to the magnetopause are generated by the cyclotron instability of anisotropic (T - /sub perpendicular//T - /sub parallel/approx. =1.2) thermal electrons when the local plasma critical energy, E/sub M/ = B 2 /8πN, falls to values (E/sub M/ approx.10--30 eV) close to or below the electron thermal energy, 25 eV, as a result of decreases in B. The lion roars are terminated by increases in the ambient magnetic field magnitude and consequential increases in E/sub M/ to values greater than 100 eV. Because there are few resonant particles at these high energies, the growth rate decreases by 3 orders of magnitude and measurable growth ceases. The value of the absolute upper limit of the frequency of unstable waves predicted by theory, ω/sub max/ = A - Ω - /(A - +1), is compared with observations. The predictions and observations are found to be in general, but not exact, agreement. Several possible explanations are explored. The quasi-periodic, approx.20-s magnetic and plasma oscillations which cause the variations in E/sub M/ and hence alternately drive the cyclotron waves unstable and then stable are also investigated

Role of substrate and annealing temperature on the structure of ZnO and Al{sub x}Zn{sub 1−x}O thin films for solar cell applications

Energy Technology Data Exchange (ETDEWEB)

Nambala, Fred Joe [Department of Physics, University of Pretoria, Private bag X20, Hatfield 0028 (South Africa); Department of Physics, University of Zambia, PO Box 32379, Great East Road Campus, Lusaka (Zambia); Nel, Jacqueline M.; Machatine, Augusto G.J. [Department of Physics, University of Pretoria, Private bag X20, Hatfield 0028 (South Africa); Mwakikunga, Bonex W. [DST/CSIR National Centre for Nano-Structured Materials, PO Box 395, Pretoria (South Africa); Njoroge, Eric G. [Department of Physics, University of Pretoria, Private bag X20, Hatfield 0028 (South Africa); Maabong, Kelebogile [Department of Physics, University of Pretoria, Private bag X20, Hatfield 0028 (South Africa); Physics Department, University of Botswana, Private Bag 0022, Gaborone (Botswana); Das, Arran G.M. [Monash University, Private Bag X60, Roodepoort 1725 (South Africa); Diale, Mmantsae, E-mail: mmantsae.diale@up.ac.za [Department of Physics, University of Pretoria, Private bag X20, Hatfield 0028 (South Africa)

2016-01-01

This paper reports on the deposition of pure and 5 at% Al doped ZnO (AZO) prepared by sol–gel and applied to the substrates by spin-coating, and the role of annealing temperature on the crystallinity of these layers. It is found that both ZnO and AZO are largely amorphous when coated on glass compared to n-Si(111), as substrates. On both substrates, X-ray diffraction (XRD) shows that the crystallinity improves as annealing temperature is raised from 200 to 600 °C with better crystallinity on Si substrates. The thickness of the films on substrates was determined as 120 nm by Rutherford backscattering spectroscopy (RBS). Specular ultra-violet visible (UV–vis) gives the direct transition optical band gaps (E{sub g}) for AZO as-deposited films are 2.60 and 3.35 eV while that of 600 °C annealed films are 3.00 and 3.60 eV. The E{sub g} calculated from diffuse reflectance spectroscopy (DRS) UV–vis are more diverse in ZnO- and AZO-Si than the ZnO- and AZO-glass samples, although in both sets the E{sub g} tend to converge after annealing 600 °C. The Raman spectra of samples show multiphonon processes of higher order from the AZO and substrates. It is found that residual stresses are related to E{sub 2} Raman mode.

Phonon and thermal properties of exfoliated TaSe{sub 2} thin films

Energy Technology Data Exchange (ETDEWEB)

Yan, Z.; Jiang, C.; Renteria, J. [Nano-Device Laboratory, Department of Electrical Engineering, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Pope, T. R.; Tsang, C. F.; Stickney, J. L.; Salguero, T. T., E-mail: salguero@uga.edu, E-mail: balandin@ee.ucr.edu [Department of Chemistry, University of Georgia, Athens, Georgia 30602 (United States); Goli, P. [Materials Science and Engineering Program, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Balandin, A. A., E-mail: salguero@uga.edu, E-mail: balandin@ee.ucr.edu [Nano-Device Laboratory, Department of Electrical Engineering, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States); Materials Science and Engineering Program, Bourns College of Engineering, University of California–Riverside, Riverside, California 92521 (United States)

2013-11-28

We report on the phonon and thermal properties of thin films of tantalum diselenide (2H-TaSe{sub 2}) obtained via the “graphene-like” mechanical exfoliation of crystals grown by chemical vapor transport. The ratio of the intensities of the Raman peak from the Si substrate and the E{sub 2g} peak of TaSe{sub 2} presents a convenient metric for quantifying film thickness. The temperature coefficients for two main Raman peaks, A{sub 1g} and E{sub 2g}, are −0.013 and −0.0097 cm{sup −1}/{sup o}C, respectively. The Raman optothermal measurements indicate that the room temperature thermal conductivity in these films decreases from its bulk value of ∼16 W/mK to ∼9 W/mK in 45-nm thick films. The measurement of electrical resistivity of the field-effect devices with TaSe{sub 2} channels shows that heat conduction is dominated by acoustic phonons in these van der Waals films. The scaling of thermal conductivity with the film thickness suggests that the phonon scattering from the film boundaries is substantial despite the sharp interfaces of the mechanically cleaved samples. These results are important for understanding the thermal properties of thin films exfoliated from TaSe{sub 2} and other metal dichalcogenides, as well as for evaluating self-heating effects in devices made from such materials.

Upper limit for the emission of monoenergetic photons in Y(1S)- and Y(2S)-meson decays

International Nuclear Information System (INIS)

Albrecht, H.; Binder, U.; Harder, G.; Lembke-Koppitz, I.; Philipp, A.; Schmidt-Parzefall, W.; Schroeder, H.; Schulz, H.D.; Wurth, R.; Drescher, H.; Graewe, B.; Matthiesen, U.; Scheck, H.; Spengler, J.; Wegener, D.; Edwards, K.W.; Kapitza, H.; Yun, J.C.; Frisken, W.R.; Fukunaga, C.; Goddard, M.; Gilkinson, D.J.; Gingrich, D.M.; Kim, P.C.H.; Kutschke, R.; MacFarlane, D.B.; McKenna, J.A.; Orr, R.S.; Padley, P.; Prentice, J.D.; Seywerd, H.C.J.; Stacey, B.J.; Yoon, T.S.; Ammar, R.; Coppage, D.; Davis, R.; Kanekal, S.; Kwak, N.; Kernel, G.; Plesko, M.; Childers, R.; Darden, C.W.; Gennow, H.

1985-08-01

We report the results of a search for monoenergetic photons in the decay of both the Y(1S)- and the Y(2S)-meson. Photons converted in the beam tube or the drift chamber inner wall, and photons detected with the barrel shower counters of the ARGUS detector, respectively, have been used in the analysis. No narrow peak is observed in the energy interval 0.5 GeV<=Esub(γ)<=4.0 GeV. (orig.)

Elastic scattering, inelastic scattering, and transfer reactions induced by 12C bombardment of 12C

International Nuclear Information System (INIS)

Stokstad, R.G.; Wieland, R.M.; Fulmer, C.B.; Hensley, D.C.; Raman, S.; Snell, A.H.; Stelson, P.H.

1977-06-01

Graphs and tables of differential cross sections are presented for the elastic scattering of 12 C by 12 C, the single excitation (Q = -4.43 MeV) and the mutual excitation (Q = -8.86 MeV) for 14 bombarding energies in the range 70.7 less than or equal to E/sub lab/ less than or equal to 126.7 MeV. Differential cross sections for one- and two-nucleon transfer are presented for E/sub lab/ = 93.8 MeV

Polarized beam asymmetry for. gamma. d. -->. Peta in the energy range 0. 4-0. 8 GeV

Energy Technology Data Exchange (ETDEWEB)

Adamyan, F.V.; Arustamyan, G.V.; Galumyan, P.I.; Grabsky, V.H.; Hakopyan, H.H.; Karapetyan, V.V.; Vartapetyan, H.A.

1983-01-01

Measurements of the polarized beam asymmetry for deuteron photodisintegration ..gamma..d ..-->.. Peta have been carried out in the energy range E/sub ..gamma../ = 0.4-0.8 GeV and at angles theta/sub p//sup cm/ = 45/sup 0/-75/sup 0/. The results obtained are in disagreement with theoretical predictions which take into account the dibaryon resonance contribution. The data qualitative analysis indicates the weakness of isoscalar dibaryon amplitudes near E/sub ..gamma../ = 400 MeV. 8 references, 1 figure.

Neutron environment in d + Li facilities

International Nuclear Information System (INIS)

Mann, F.M.; Schmittroth, F.; Carter, L.L.

1980-01-01

A microscopic d + Li neutron yield model has been developed based upon classical models and experimental data. Using equations suggested by the Serber and evaporation models, a generalized least squares adjustment procedure generated angular yields for E/sub d/ to 40 MeV using the available experimental data. The HEDL-UCD experiment at E/sub d/ = 35 was used to adjust parameters describing the neutron spectra. The model is used to predict yields, spectra, and damage responses in the FMIT Test Cell

Neutron and gamma-ray emission in the proton induced fission of {sup 238}U and {sup 242}Pu

Energy Technology Data Exchange (ETDEWEB)

Kniajeva, G.N.; Krupa, L.; Bogachev, A.A.; Chubarian, G.G.; Dorvaux, O.; Itkis, I.M.; Itkis, M.G.; Kliman, J.; Khlebnikov, S.; Kondratiev, N.A.; Kozulin, E.M.; Lyapin, V.; Materna, T.; Pokrovsky, I.V.; Rubchenya, V.A.; Trzaska, W.H.; Vakhtin, D.; Voskressenski, V.M

2004-04-05

Average prescission M{sup pre}{sub n} and postscission M{sup post}{sub n} neutron multiplicities as well as average {gamma}-ray multiplicity , average energy <E{sub {gamma}}> emitted by {gamma}-rays as a function of mass and total kinetic energy (TKE) of fission fragments were measured in proton induced reactions p+{sup 242}Pu{yields}{sup 243}Am, p+{sup 238}U{yields}{sup 239}Np at proton energy E{sub p}=13, 20 and 55 MeV.

Present status of research on Re-186 radiopharmaceuticals at Radioisotope Production Center

Energy Technology Data Exchange (ETDEWEB)

Mutalib, A [Radioisotope Production Center, National Atomic Energy Agency Kawasan PUSPIPTEK, Serpong (Indonesia)

1998-10-01

Rhenium shows a close chemical similarity to technetium and is suitable for radiotherapy because the {beta}-emitting radionuclides {sup 186}Re (t{sub 1/2} 90 h, E{sub {beta}} = 1.1 MeV, E{sub {gamma}} = 137 keV) and {sup 188}Re (t{sub 1/2} = 17 h, E{sub {beta}} = 2.1 MeV). The {gamma}-emission associated with decay of {sup 186}Re is also useful in scintigraphy. The research on {sup 186}Re radiopharmaceuticals at Radioisotope Production Center has been carried out since April 1997. Interest in radioimmunotherapy (RIT) led us to the development of labeling antibodies with rhenium isotopes. Although there are several methods for coupling radiometal to antibody, we prefer an indirect labeling method in which a bifunctional chelating agent is used for coupling of {sup 186}Re to monoclonal antibodies. In this report we outline the study on the preparation of {sup 186}Re DMSA-TFP as precursor for labeling with monoclonal antibody. (author)

Study of the correlation of gamma-ray families with the EAS by the Monte-Carlo simulation and a suggested future experiment

International Nuclear Information System (INIS)

Kasahara, K.; Torii, S.; Yuda, T.

1981-01-01

To examine information which may be obtained by the simultaneous observation of gamma-ray families and accompanying air showers, a Monte-Carlo simulation is carried out under various assumptions for primary cosmic rays and nuclear interactions. It is shown that only proton primary can produce those families that have energy greater than ΣEsub(γ) approximately=100 TeV with air shower size less than 10 5 ; other heavy primaries such as alpha, carbon etc always generate larger sizes than 10 5 for families ΣEsub(γ)>=100 TeV. Therefore we will be able to select families generated by proton primaries and discuss the character of nuclear interaction at very high energies without suffering from the problem of imitations of various new characters (large Pt, large multiplicity etc) by heavy primaries. Moreover, it is shown that the chemical composition of the primaries at >=10 15 eV region is possibly studied through ΣEsub(γ)-size correlation

Hydrolytic cleavage of ammonia-borane complex for hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Mohajeri, Nahid; T-Raissi, Ali; Adebiyi, Olawale [Hydrogen R and D Division, Florida Solar Energy Center, University of Central Florida 1679 Clearlake Rd., Cocoa, FL 32955 (United States)

2007-05-15

A new process for generating hydrogen via near room temperature hydrolysis of AB complex using small amounts of platinum group metal catalyst has been studied. Using in situ {sup 11}B NMR spectroscopy, the overall rate of K{sub 2}Cl{sub 6}Pt catalyzed hydrolysis of AB complex was calculated to be third-order. The pre-exponential factor (A) and the activation energy (E{sub a}) of Arrhenius equation, ln k = ln A - E{sub a}/RT, were determined to be: A = 1.6 x 10{sup 11} L mol{sup -1} s{sup -1} and E{sub a} = 86.6 kJ mol{sup -1} for temperature range of (25-35 C). X-ray photoelectron spectroscopy of the residue suggested that the platinum salt was reduced from Pt{sup 4+} to Pt{sup 0} within the course of the reaction and X-ray diffraction analysis pattern for the residue showed crystallized single-phase boric acid. (author)

Hole traps in n-GaN detected by minority carrier transient spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Tokuda, Yutaka; Yamada, Yujiro; Shibata, Tatsunari; Yamaguchi, Shintaro [Department of Electrical and Electronics Engineering, Aichi Institute of Technology, Yakusa, 470-0392 Toyota (Japan); Ueda, Hiroyuki; Uesugi, Tsutomu; Kachi, Tetsu [Toyota Central R and D Laboratories, Inc., Nagakute, 480-1192 Aichi (Japan)

2011-07-15

Minority carrier transient spectroscopy (MCTS) has been applied for the detection of hole traps in n-GaN using Schottky diodes. MCTS using 355 nm light emitting diodes is performed under isothermal conditions in the temperature range 280 to 330 K for n-GaN grown by metalorganic chemical vapor deposition on sapphire. Isothermal MCTS spectra reveal the E{sub v} + 0.86 eV hole trap with the trap concentration of 1.1x10{sup 16} cm{sup -3}. The E{sub v} + 0.86 eV hole trap has the higher concentration as compared to electron traps observed by deep level transient spectroscopy. Thus, the isothermal MCTS around room temperature provides a convenient way to evaluate the dominant trap in n-GaN. It is suggested that the E{sub v} + 0.86 eV hole trap is associated with the V{sub Ga}-related defect or carbon-related defect. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Confinement of a nonionic surfactant membrane within a montmorillonite as a new way to prepare organoclay materials

Energy Technology Data Exchange (ETDEWEB)

Guegan, Regis, E-mail: regis.guegan@univ-orleans.fr [Universite d' Orleans (France); Giovanela, Marcelo [Universidade de Caxias do Sul (UCS), RS (Brazil)

2016-11-15

The aim of this study was to prepare and characterize a hybrid layered material (organoclay) with a Na-montmorillonite and the triethylene glycol mono-n-decyl ether (C{sub 10}E{sub 3} ) nonionic surfactant which forms a lamellar phase at room temperature. The synthesized organoclay was characterized by complementary techniques (Fourier transform infrared spectroscopy and X-ray diffraction). Experiments in conjunction with electron density analysis showed that a bilayer or membrane of C{sub 10}E{sub 3} was intercalated within the interlayer space of a naturally exchanged Na-montmorillonite. The intercalation of a bilayer of C{sub 10}E{sub 3} in a clay mineral offers new perspectives for the manufacturing of nanomaterials. While showing a hydrophobic surface and a large interlayer space value, the resulting organoclay preserves the compensating cations within the interlayer space allowing one to perform ion exchanges, making easier the intercalation of further organic molecules of important size with functional properties or for environmental purposes. (author)

FY10 parameters for the injection, acceleration, and extraction of gold ions in booster, AGS, and RHIC

Energy Technology Data Exchange (ETDEWEB)

Gardner, C.J.

2010-08-01

A Gold ion with charge eQ has N = 197 Nucleons, Z = 79 Protons, and (Z-Q) electrons. (Here Q is an integer and e is the charge of a single proton.) The mass is m = au - Qm{sub e} + E{sub b}/c{sup 2} (1) where a = 196.966552 is the relative atomic mass [1, 2] of the neutral Gold atom, u = 931.494013 MeV/c{sup 2} is the unified atomic mass unit [3], and m{sub e}c{sup 2} = .510998902 MeV is the electron mass [3]. E{sub b} is the binding energy of the Q electrons removed from the neutral Gold atom. This amounts to 0.332 MeV for the helium-like gold ion (Q = 77) and 0.517 MeV for the fully stripped ion. For the Au{sup 31+} ion we have E{sub b} = 13.5 keV. These numbers are given in Ref. [4].

Processes arising in the edge and diverted plasmas during ITB formation in the U-3M torsatron

Energy Technology Data Exchange (ETDEWEB)

Chechkin, V V [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Grigor' eva, L I [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Sorokovoy, E L [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Sorokovoy, Ye L [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Slavnyj, A S [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Volkov, Ye D [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Beletskij, A A [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Burchenko, P Ya [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Tsybenko, S A [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Lozin, A V [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Kulaga, A Ye; Letvinov, A P [Institute of Plasma Physics, National Science Center ' Kharkov Institute of Physics and Technology' , Akademicheskaya st. 1, 61108 Kharkov (Ukraine); Masuzaki, S; Yamazaki, K [National Institute for Fusion Science, Oroshi-cho 322-6, Toki-shi 509-5292 (Japan)

2006-05-15

Spontaneous changes in confined plasma parameters have been observed recently in the l = 3/m = 9 Uragan-3M torsatron with an RF produced and heated plasma, these being interpreted as transition to an improved confinement mode due to ITB formation near the {iota} = 1/4 rational magnetic surface. In the work presented joint studies are carried out of changes in some edge and diverted plasma characteristics that accompany ITB formation. It is shown that ITB formation induces a hard E{sub r} bifurcation at the boundary presumably driven by the ion orbit loss. As a result, E{sub r} becomes more negative, and an E{sub r} shear layer occurs, where the low-frequency microturbulence and the turbulence-induced anomalous transport are suppressed, i.e. an ETB is formed. At the pre-bifurcation phase of transition a reduction of fast ion loss takes place. The bifurcation results in an improvement of electron confinement, while the ion loss increases.

Low-energy behavior of the 3He(α,γ)7Be cross section

International Nuclear Information System (INIS)

Osborne, J.L.; Barnes, C.A.; Kavanagh, R.W.; Kremer, R.M.; Mathews, G.J.; Zyskind, J.L.; Parker, P.D.; California Inst. of Tech., Pasadena; Howard, A.J.; California Inst. of Tech., Pasadena

1984-01-01

Cross sections for the 3 He(α,γ) 7 Be reaction have been measured at several energies from Esub(c.m.)=165 to 1169 keV by counting prompt γ-rays from a windowless, differentially pumped, recirculating, 3 He gas target. The cross-section factor S 34 (Esub(c.m.)) and branching ratio γ 1 /γ 0 were determined at each energy. Cross sections were also measured at Esub(c.m.)=947 and 1255 keV by counting the γ-rays from the 7 Be produced in a 3 He gas cell with a Ni entrance foil. Combining the results of these two independent experiments yields a zero-energy intercept for the cross-section factor of S 34 (O) = 0.53+-0.03 keV x b. The relationship between these measurements and serveral theoretical calculations, and the import of the extrapolated cross section for the solar-neutrino problem are discussed. (orig.)

Study of ({alpha}, {sup 3}He) and ({alpha}, t) reactions on {sup 28}Si at 45 MeV

Energy Technology Data Exchange (ETDEWEB)

Darshan, V.P.; Sathyavathiamma, M.P.; Ramaswamy, C.R.; Raja Rao, M.; Puttaswamy, N.G.; Banerjee, S.R.; Chintalapudi, S.N. [Dept. of Phys., Bangalore Univ. (India)

1995-03-01

The {sup 28}Si({alpha}, {sup 3}He){sup 29}Si, {sup 28}Si({alpha}, t){sup 29}P and Si({alpha}, {alpha})Si reactions were studied at E{sub {alpha}} = 45 MeV. Exact finite-range (EFR) DWBA analysis was carried out for the transitions to the ground state and to five excited states in {sup 29}Si and {sup 29}P. Spectroscopic strengths G were extracted for all the states and were compared with the predictions from shell-model and quasi-particle core-coupling calculations. Similar EFR-DWBA analyses were carried out from available (unpublished) data for the {sup 28}Si({alpha}, {sup 3}He){sup 29}Si reaction at E{sub {alpha}} = 64.9 and 120 MeV, and for the {sup 28}Si({alpha}, t){sup 29}P reaction at E{sub {alpha}} = 50 and 64.9 MeV. The comparison of experimental and theoretical values of G are provided. (author)

Band structural properties of MoS2 (molybdenite)

International Nuclear Information System (INIS)

Gupta, V.P.

1980-01-01

Semiconductivity and superconductivity in MoS 2 (molybdenite) can be understood in terms of the band structure of MoS 2 . The band structural properties of MoS 2 are presented here. The energy dependence of nsub(eff) and epsilon(infinity)sub(eff) is investigated. Using calculated values of nsub(eff) and epsilon(infinity)sub(eff), the Penn gap has been determined. The value thus obtained is shown to be in good agreement with the reflectivity data and also with the value obtained from the band structure. The Ravindra and Srivastava formula has been shown to give values for the isobaric temperature gradient of Esub(G)[(deltaEsub(G)/deltaT)sub(P)], which are in agreement with the experimental data, and the contribution to (deltaEsub(G)/deltaT)sub(P) due to the electron lattice interaction has been evaluated. In addition, the electronic polarizability has been calculated using a modified Lorentz-Lorenz relation. (author)

Optical properties of P3HT:tributylphosphine oxide-capped CdSe nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Benchaabane, A. [Faculte des Sciences d' Amiens, Laboratoire de Physique de la Matiere Condensee, Amiens (France); Universite Tunis El-Manar, Laboratoire de Materiaux avances et phenomenes quantiques, Faculte des Sciences de Tunis El Manar, Tunis (Tunisia); Universite Arabe des Sciences, Ecole Superieure d' Ingenieurs et des Etudes Technologiques, Tunis (Tunisia); Ben Hamed, Z.; Kouki, F.; Bouchriha, H. [Universite Tunis El-Manar, Laboratoire de Materiaux avances et phenomenes quantiques, Faculte des Sciences de Tunis El Manar, Tunis (Tunisia); Lahmar, A.; Zellama, K.; Zeinert, A. [Faculte des Sciences d' Amiens, Laboratoire de Physique de la Matiere Condensee, Amiens (France); Sanhoury, M.A. [Laboratoire de Chimie Organique Structurale, Synthese et Etudes Physicochimiques, Tunis (Tunisia)

2016-08-15

The optical properties of nanocomposite layers prepared by incorporation of tributylphosphine oxide (TBPO)-capped CdSe nanocrystals (NCs) in a P3HT polymer matrix are studied using different nanocrystal concentrations. Reflection spectra analyzed through Kim oscillator model lead to the determination of optical constants such as refractive index n, extinction coefficient k, dielectric permittivity ε and absorption coefficient α. Using the common Cauchy, Drude-Lorentz, Tauc and single-effective-oscillator theoretical models, we have determined the values of static refractive index n{sub s} and permittivity ε{sub s}, plasma frequency ω{sub p}, carrier density N, optical band gap E{sub g} and oscillator and dispersion energies E{sub 0} and E{sub d}, respectively. It is found that TBPO-capped CdSe NCs concentration affects the optoelectronic parameters of the nanocomposite thin films. Moreover, the disorder of this hybrid system is also studied by the determination of Urbach energy, which increases with TBPO-capped CdSe concentration. (orig.)

Measurement of fission cross-section for the {sup 232}Th(n,f){sup 141}Ba reaction induced by neutrons around 14 MeV

Energy Technology Data Exchange (ETDEWEB)

Lan, Chang-Lin; Fang, Kai-Hong [Lanzhou University, School of Nuclear Science and Technology, Lanzhou, Gansu Province (China); Lanzhou University, Engineering Research Center for Neutron Application, Ministry of Education, Lanzhou, Gansu Province (China); Liu, Shuang-Tong; Lv, Tao; Wang, Qiang; Zhang, Zheng-Wei [Lanzhou University, School of Nuclear Science and Technology, Lanzhou, Gansu Province (China); Lai, Cai-Feng [Chinese Academy of Engineering Physics, Institute of Nuclear Physics and Chemistry, Mianyang, Sichuan Province (China)

2016-11-15

The fission cross-section of the {sup 232}Th(n,f){sup 141}Ba reaction induced by neutrons around 14 MeV was measured precisely with the neutron activation and off-line gamma-ray spectrometric technique. Neutron fluence was monitored on-line using the accompanying α-particles from the {sup 3}H({sup 2}H,n){sup 4}He reaction, whereas the neutron energies were measured by the method of cross-section ratios of {sup 90}Zr(n,2n){sup 89}Zr to {sup 93}Nb(n,2n){sup 92m}Nb reactions. The experimentally determined {sup 232}Th(n,f){sup 141}Ba reaction cross-sections were 12.2 ± 0.4 mb at E{sub n} = 14.1 ± 0.3 MeV, 13.0 ± 0.5 mb at E{sub n} = 14.5 ± 0.3 MeV and 13.3 ± 0.5 mb at E{sub n} = 14.7 ± 0.3 MeV, respectively. (orig.)

Measurement of inclusive ep cross sections at high Q{sup 2} at √(s) = 225 and 252 GeV and of the longitudinal proton structure function F{sub L} at HERA

Energy Technology Data Exchange (ETDEWEB)

Andreev, V.; Belousov, A.; Fomenko, A.; Gogitidze, N.; Lebedev, A.; Malinovski, E.; Rusakov, S.; Vazdik, Y. [Lebedev Physical Institute, Moscow (Russian Federation); Baghdasaryan, A.; Baghdasaryan, S.; Zohrabyan, H. [Yerevan Physics Institute, Yerevan (Armenia); Begzsuren, K.; Ravdandorj, T.; Tseepeldorj, B. [Institute of Physics and Technology of the Mongolian Academy of Sciences, Ulaanbaatar (Mongolia); Belov, P.; Brinkmann, M.; Britzger, D.; Campbell, A.J.; Dodonov, V.; Eckerlin, G.; Elsen, E.; Fleischer, M.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Gouzevitch, M.; Grebenyuk, A.; Habib, S.; Haidt, D.; Kleinwort, C.; Krueger, K.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lobodzinski, B.; Meyer, A.B.; Meyer, J.; Niebuhr, C.; Olsson, J.E.; Ozerov, D.; Pahl, P.; Petrukhin, A.; Pirumov, H.; Pitzl, D.; Placakyte, R.; Radescu, V.; Raspereza, A.; Schmitt, S.; Sefkow, F.; Shushkevich, S.; South, D.; Steder, M.; Wuensch, E. [DESY, Hamburg (Germany); Boudry, V.; Specka, A. [LLR, Ecole Polytechnique, CNRS/IN2P3, Palaiseau (France); Bradt, G. [Oxford University, Department of Physics, Oxford (United Kingdom); Brisson, V.; Jacquet, M.; Pascaud, C.; Zhang, Z.; Zomer, F. [LAL, Universite Paris-Sud, CNRS/IN2P3, Orsay (France); Buniatyan, A.; Huber, F.; Sauter, M.; Schoening, A. [Universitaet Heidelberg, Physikalisches Institut, Heidelberg (Germany); Bylinkin, A.; Bystritskaya, L.; Fedotov, A.; Rostovtsev, A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Cantun Avila, K.B.; Contreras, J.G. [CINVESTAV, Departamento de Fisica Aplicada, Merida, Yucatan (Mexico); Ceccopieri, F.; Wolf, E.A. de; Favart, L.; Hreus, T.; Janssen, X.; Roosen, R.; Mechelen, P. van [Brussels and Universiteit Antwerpen, Inter-University Institute for High Energies ULB-VUB, Antwerp (Belgium); Cerny, K.; Pokorny, B.; Polifka, R.; Salek, D.; Valkarova, A.; Zacek, J.; Zlebcik, R. [Charles University, Faculty of Mathematics and Physics, Prague (Czech Republic); Chekelian, V.; Grindhammer, G.; Kiesling, C.; Olivier, B. [Max-Planck-Institut fuer Physik, Munich (Germany); Dainton, J.B.; Gabathuler, E.; Greenshaw, T.; Klein, M.; Kretzschmar, J.; Laycock, P.; Maxfield, S.J.; Mehta, A.; Patel, G.D. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Daum, K.; Meyer, H. [Universitaet Wuppertal, Fachbereich C, Wuppertal (Germany); Diaconu, C.; Hoffmann, D.; Sauvan, E.; Vallee, C. [CPPM, Aix-Marseille Univ, CNRS/IN2P3, Marseille (France); Dobre, M.; Rotaru, M. [National Institute for Physics and Nuclear Engineering (NIPNE), Bucharest (Romania); Dossanov, A. [Universitaet Hamburg, Institut fuer Experimentalphysik, Hamburg (Germany); Max-Planck-Institut fuer Physik, Munich (Germany); Dubak, A. [Max-Planck-Institut fuer Physik, Munich (Germany); University of Montenegro, Faculty of Science, Podgorica (Montenegro); Egli, S.; Hildebrandt, M.; Horisberger, R. [Paul Scherrer Institut, Villigen (Switzerland); Feltesse, J.; Perez, E.; Schoeffel, L. [CEA, DSM/Irfu, CE-Saclay, Gif-sur-Yvette (France); Ferencei, J. [Slovak Academy of Sciences, Institute of Experimental Physics, Kosice (Slovakia); Goerlich, L.; Mikocki, S.; Nowak, G.; Sopicki, P.; Turnau, J. [Institute for Nuclear Physics, Cracow (Poland); Grab, C. [ETH, Institut fuer Teilchenphysik, Zurich (Switzerland); Henderson, R.C.W. [University of Lancaster, Department of Physics, Lancaster (United Kingdom); Herbst, M.; Jung, A.W.; Schultz-Coulon, H.C. [Universitaet Heidelberg, Kirchhoff-Institut fuer Physik, Heidelberg (Germany); Hladka, J.; Reimer, P. [Academy of Sciences of the Czech Republic, Institute of Physics, Prague (Czech Republic); Jung, H. [Brussels and Universiteit Antwerpen, Inter-University Institute for High Energies ULB-VUB, Antwerp (Belgium); DESY, Hamburg (Germany); Kapichine, M.; Morozov, A.; Spaskov, V. [Joint Institute for Nuclear Research, Dubna (RU); Kogler, R.; Nowak, K. [Universitaet Hamburg, Institut fuer Experimentalphysik, Hamburg (DE); Kostka, P.; Lange, W.; Naumann, T. [DESY, Zeuthen (DE); Landon, M.P.J.; Rizvi, E.; Traynor, D. [University of London, School of Physics and Astronomy, Queen Mary, London (GB); Lubimov, V. [Institute for Theoretical and Experimental Physics, Moscow (RU); Martyn, H.U. [I. Physikalisches Institut der RWTH, Aachen (DE); Mueller, K.; Robmann, P.; Straumann, U.; Truoel, P. [Physik-Institut der Universitaet Zuerich, Zurich (CH); Newman, P.R.; Thompson, P.D. [School of Physics and Astronomy, University of Birmingham, Birmingham (GB); Picuric, I.; Raicevic, N. [University of Montenegro, Faculty of Science, Podgorica (ME); Sankey, D.P.C. [STFC, Rutherford Appleton Laboratory, Oxfordshire (GB); Soloviev, Y. [DESY, Hamburg (DE); Lebedev Physical Institute, Moscow (RU); Stella, B. [Universita di Roma Tre (IT); INFN Roma 3, Dipartimento di Fisica, Rome (IT); Sykora, T. [Brussels and Universiteit Antwerpen, Inter-University Institute for High Energies ULB-VUB, Antwerp (BE); Charles University, Faculty of Mathematics and Physics, Prague (CZ); Tsakov, I. [Institute for Nuclear Research and Nuclear Energy, Sofia (BG); Wegener, D. [Institut fuer Physik, TU Dortmund, Dortmund (DE); Collaboration: H1 Collaboration

2014-04-15

Inclusive ep double differential cross sections for neutral current deep inelastic scattering are measured with the H1 detector at HERA.The data were taken with a lepton beam energy of 27.6 GeV and two proton beam energies of E{sub p} = 460 and 575 GeV corresponding to centre-of-mass energies of 225 and 252 GeV, respectively. The measurements cover the region of 6.5 x 10{sup -4} ≤ x ≤ 0.65 for 35 ≤ Q{sup 2} ≤ 800 GeV{sup 2} up to y = 0.85. The measurements are used together with previously published H1 data at E{sub p} = 920 GeV and lower Q{sup 2} data at E{sub p} = 460, 575 and 920 GeV to extract the longitudinal proton structure function F{sub L} in the region 1.5 ≤ Q{sup 2} ≤ 800 GeV{sup 2}. (orig.)

Single-particle resonance levels in {sup 14}O examined by N13+p elastic resonance scattering

Energy Technology Data Exchange (ETDEWEB)

Teranishi, T. [Dept. of Physics, Kyushu Univ., 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)]. E-mail: teranishi@nucl.phys.kyushu-u.ac.jp; Kubono, S. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Yamaguchi, H. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); He, J.J. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Saito, A. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Fujikawa, H. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Amadio, G. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Niikura, M.; Shimoura, S. [Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Wakabayashi, Y. [Dept. of Physics, Kyushu Univ., 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan)]|[Center for Nuclear Study (CNS), Univ. of Tokyo, Wako Branch at RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Nishimura, S.; Nishimura, M. [RIKEN Nishina Center for Accelerator-Based Science, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Moon, J.Y.; Lee, C.S. [Dept. of Physics, Chung-Ang Univ., Seoul 156-756 (Korea, Republic of); Odahara, A. [Nishinippon Inst. of Technology, Kanda, Fukuoka 800-0394 (Japan); Sohler, D. [Inst. of Nuclear Research (ATOMKI), H-4001 Debrecen, P.O. Box 51 (Hungary); Khiem, L.H. [Inst. of Physics and Electronics (IOP), Vietnamese Academy for Science and Technology (VAST), 10 Daotan, Congvi, Badinh, P.O. Box 429-BOHO, Hanoi 10000 (Viet Nam); Li, Z.H.; Lian, G.; Liu, W.P. [China Inst. of Atomic Energy, P.O. Box 275(46), Beijing 102413 (China)

2007-06-28

Single-particle properties of low-lying resonance levels in {sup 14}O have been studied efficiently by utilizing a technique of proton elastic resonance scattering with a {sup 13}N secondary beam and a thick proton target. The excitation functions for the N13+p elastic scattering were measured over a wide energy range of E{sub CM}=0.4-3.3 MeV and fitted with an R-matrix calculation. A clear assignment of J{sup {pi}}=2{sup -} has been made for the level at E{sub x}=6.767(11) MeV in {sup 14}O for the first time. The excitation functions show a signature of a new 0{sup -} level at E{sub x}=5.71(2) MeV with {gamma}=400(100) keV. The excitation energies and widths of the {sup 14}O levels are discussed in conjunction with the spectroscopic structure of A=14 nuclei with T=1.

Recommended engineering practice to enhance the EMI/EMP immunity of electric power systems

Energy Technology Data Exchange (ETDEWEB)

Wagner, C.L.; Feero, W.E. (Electric Research and Management, Inc., State College, PA (United States))

1992-12-01

Many papers and reports have been written on studies conducted by the Oak Ridge National Laboratory and investigations by others on the effect of high-altitude electromagnetic pulses (HEMP) on electric power systems. More than 100 of the published unclassified documents were reviewed with the objectives of: 1. summarizing the mitigation methods suggested in the documents and providing a subjective evaluation of each 2. discussing various standards . that presently apply to the effects of HEMP on utility systems and suggesting additions or modifications or new standards where deficiencies appear to exist; and 3. recommending future studies or actions to improve the utility response to HEMP. While all three components of HEMP were mentioned, only the early-time short-duration E[sub 1] pulse and the late-time long-duration E[sub 3] pulse were considered in detail; the E[sub 2] intermediate component was not considered to affect the power system significantly.

Recommended engineering practice to enhance the EMI/EMP immunity of electric power systems

Energy Technology Data Exchange (ETDEWEB)

Wagner, C.L.; Feero, W.E. [Electric Research and Management, Inc., State College, PA (United States)

1992-12-01

Many papers and reports have been written on studies conducted by the Oak Ridge National Laboratory and investigations by others on the effect of high-altitude electromagnetic pulses (HEMP) on electric power systems. More than 100 of the published unclassified documents were reviewed with the objectives of: 1. summarizing the mitigation methods suggested in the documents and providing a subjective evaluation of each 2. discussing various standards . that presently apply to the effects of HEMP on utility systems and suggesting additions or modifications or new standards where deficiencies appear to exist; and 3. recommending future studies or actions to improve the utility response to HEMP. While all three components of HEMP were mentioned, only the early-time short-duration E{sub 1} pulse and the late-time long-duration E{sub 3} pulse were considered in detail; the E{sub 2} intermediate component was not considered to affect the power system significantly.

Production and identification of an isomeric state in 217Pa and the new isotope 218Pa

International Nuclear Information System (INIS)

Schmidt, K.H.; Faust, W.; Muenzenberg, G.; Ewald, H.; Guettner, K.; Clerc, H.G.; Lang, W.; Wohlfarth, H.; Pielenz, K.

1977-02-01

Evaporation residues produced in the reaction 40Ar(176 MeV) + 181Ta were separated from the primary beam by the velocity filter SHIP and detected by a ΔE-E counter telescope. The technique of delayed coincidences was applied to individually identify the reaction products implanted into a Si-surface barrier detector by their subsequent alpha decays. The previously unknown nucleus 218Pa was identified by its known daughter decays. 218Pa was found to decay with Esub(α) = (9.614 +- 0.015) MeV, T(1/2) = (140 +- 50) μs and probably also with Esub(α) = (9.535 +- 0.020) MeV, T(1/2) = (150 + 100 - 50) μs. The half-life of the 8.33 MeV alpha decay of 217Pa was determined to be (o.2 +- 0.4) ms. Anew isomer in 217 Pa was found which decays with Esub(α) = (10.16 +- 0.02) MeV and T(1/2) = (1.8 +- 0.5) ms. (orig./BJ) [de

Peak systolic pressure-volume relationships in man

International Nuclear Information System (INIS)

Adachi, Haruhiko; Sugihara, Hiroki; Nakagawa, Hiroaki; Katsume, Hiroshi; Ochiai, Masakazu; Ijichi, Hamao

1985-01-01

We determined the relationship between left ventricular (LV) peak systolic pressure (PSP) and end-systolic volume, non-invasively using cuff sphygmomanometry and radionuclide angiocardiography (RNA). Systolic blood pressure (SBP) measured in the arm was substituted for PSP. LV enddiastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) were determined by a non-geometric method of gated RNA and recorded in three different hemodynamic states: at rest (basal state), during increased SBP after angiotensin administration (initial dose, 1-2 μg/min) and during decreased SBP after nitrate (sublingual nitroglycerin, 0.3-0.6 mg, or intravenous isosorbide dinitrate, 0.5-1.0 mg/min). The reproducibility of this method, tested in six subjects, proved to be good. Fifty-five subjects were divided into four groups based on EF at rest. The EDV and ESV were increased by angiotensin, and decreased by nitrate in all groups. EF was decreased by angiotensin and increased by nitrate. In contrast, the changes in PSP/ESVI due to these drugs remained in a narrow range in all groups. The regression lines of the PSP/ESVI relationship were almost linear and were steeper in the group with higher EF. Esub(max), the slope of the lines, was 5.75 +- 3.48 mmHg/ml/m 2 in group 1 (EF>50%), 3.16 +- 1.83 mmHg/ml/m 2 in group 2 (EF 49-40%), 2.27 +- 0.86 mmHg/ml/m 2 in group 3 (EF 39-30%) and 0.59 +- 0.50 mmHg/ml/m 2 in group 4 (EF<29%). The theoretical volume at zero pressure (VoI) did not meet in a definite value and was not related to EF at rest. Thus, the left ventricular peak systolic pressure-end-systolic volume relationship can be assessed non-invasively from radionuclide angiocardiography, which can be widely used for the evaluation of ventricular contractility, even in patients with asynergic ventricular contraction for whom echocardiography is unsuitable in measuring ventricular volume. (author)

Effect of Ni doping on structural and optical properties of Zn{sub 1−x}Ni{sub x}O nanopowder synthesized via low cost sono-chemical method

Energy Technology Data Exchange (ETDEWEB)

Singh, Budhendra, E-mail: bksingh@ua.pt [TEMA-NRD, Mechanical Engineering Department, Aveiro Institute of Nanotechnology (AIN), University of Aveiro, 3810-193 Aveiro (Portugal); Kaushal, Ajay, E-mail: ajay.kaushal@ua.pt [Department of Ceramic and Glass Engineering, CICECO, University of Aveiro, 3810-193 Aveiro (Portugal); Bdikin, Igor [TEMA-NRD, Mechanical Engineering Department, Aveiro Institute of Nanotechnology (AIN), University of Aveiro, 3810-193 Aveiro (Portugal); Venkata Saravanan, K. [Department of Physics, School of Basic and Applied Sciences, Central University of Tamil Nadu, Thiruvarur 610101 (India); Ferreira, J.M.F. [Department of Ceramic and Glass Engineering, CICECO, University of Aveiro, 3810-193 Aveiro (Portugal)

2015-10-15

Highlights: • Pure and Ni doped ZnO nanopowders were synthesized by low cost sonochemical method. • The optical properties of Zn{sub 1−x}Ni{sub x}O nanopowders can be tuned by varying Ni content. • The results reveal the solubility limit of Ni into ZnO matrix as below 8%. - Abstract: Zn{sub 1−x}Ni{sub x}O nanopowders with different Ni contents of x = 0.0, 0.04 and 0.08 were synthesized via cost effective sonochemical reaction method. X-ray diffraction (XRD) pattern reveals pure wurtzite phase of prepared nanostructures with no additional impurity peaks. The morphology and dimensions of nanoparticles were investigated using scanning electron microscope (SEM). A sharp and strong peak for first order optical mode for wurtzite zinc oxide (ZnO) structure was observed at ∼438 cm{sup −1} in Raman spectra. The calculated optical band gap (E{sub g}) from UV–vis transmission data was found to decrease with increase in Ni content. The observed red shift in E{sub g} with increasing Ni content in ZnO nanopowders were in agreement with band gap behaviours found in their photoluminescence (PL) spectra. The synthesised ZnO nanopowders with controlled band gap on Ni doping reveals their potential for use in various electronic and optical device applications. The results were discussed in detail.

A study of the Fe-based superconductor SmFeAsO{sub 1-x}F{sub x} by x-ray photoelectron spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Zhang, Y; Chen, Y L; Cui, Y J; Cheng, C H; Zhao, Y [Key Laboratory of Magnetic Levitation Technologies and Maglev Trains (Ministry of Education of China), Superconductivity R and D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu, Sichuan 610031 (China); Zhang, H [Department of Physics, Peking University, Beijing 100871 (China)], E-mail: yzhao@swjtu.edu.cn

2009-01-15

The electronic structure of the Fe-based superconductor SmFeAsO{sub 1-x}F{sub x} (x = 0 and 0.2) is studied with x-ray photoemission spectroscopy (XPS) through comparing the band structures of the nonsuperconducting parent material SmFeAsO and the superconducting SmFeAsO{sub 0.8}F{sub 0.2} (T{sub c} = 52.5 K). A small peak centered at 0.2 eV below the Fermi level, E{sub F}, in the valence band is observed in the parent material SmFeAsO, which is due to the low-spin state of the Fe 3d electrons. With fluorine doping, the peak at 0.2 eV disappears and a broad plateau forms near the Fermi level; in the meantime, the density of states at E{sub F} is slightly suppressed. The O 1s and Sm 3d core levels shift towards high energy by {approx}0.55 eV with fluorine doping, but in a sharp comparison, the Fe 2p and As 3d core levels do not shift significantly (the binding energy shift is less than 0.01 eV). It is deduced from the core-level shifts that the Fermi level of the system moves up by 0.55 eV by fluorine doping.

Estradiol and endocrine disrupting compounds adversely affect development of sea urchin embryos at environmentally relevant concentrations

Energy Technology Data Exchange (ETDEWEB)

Roepke, Troy A. [Bodega Marine Laboratory, University of California, Davis, POB 247, Bodega Bay, CA 94923 (United States); Snyder, Mark J. [Bodega Marine Laboratory, University of California, Davis, POB 247, Bodega Bay, CA 94923 (United States); Cherr, Gary N. [Bodega Marine Laboratory, University of California, Davis, POB 247, Bodega Bay, CA 94923 (United States) and Departments of Environmental Toxicology and Nutrition, One Shields Avenue, University of California, Davis, CA 95616 (United States)]. E-mail: gncherr@ucdavis.edu

2005-01-26

Environmental endocrine disrupting compounds (EDCs) are a wide variety of chemicals that typically exert effects, either directly or indirectly, through receptor-mediated processes, thus mimicking endogenous hormones and/or inhibiting normal hormone activities and metabolism. Little is known about the effects of EDCs on echinoderm physiology, reproduction and development. We exposed developing sea urchin embryos (Strongylocentrotus purpuratus and Lytechinus anamesus) to two known EDCs (4-octylphenol (OCT), bisphenol A (BisA)) and to natural and synthetic reproductive hormones (17{beta}-estradiol (E{sub 2}), estrone (E{sub 1}), estriol (E{sub 3}), progesterone (P{sub 4}) and 17{alpha}-ethynylestradiol (EE{sub 2})). In addition, we studied two non-estrogenic EDCs, tributyltin (TBT) and o,p-DDD. Successful development to the pluteus larval stage (96 h post-fertilization) was used to define EDC concentration-response relationships. The order of compound potency based on EC{sub 50} values for a reduction in normal development was as follows: TBT {sub L.anamesus} > OCT > TBT {sub S.{sub p}}{sub urpuratus} >> E{sub 2} > EE{sub 2} > DDD >> BisA > P{sub 4} > E{sub 1} >> E{sub 3}. The effect of TBT was pronounced even at concentrations substantially lower than those commonly reported in heavily contaminated areas, but the response was significantly different in the two model species. Sea urchin embryos were generally more sensitive to estrogenic EDCs and TBT than most other invertebrate larvae. Stage-specific exposure experiments were conducted to determine the most sensitive developmental periods using blastula, gastrula and post-gastrula (pluteus) stages. The stage most sensitive to E{sub 2}, OCT and TBT was the blastula stage with less overall sensitivity in the gastrula stage, regardless of concentration. Selective estrogen receptor modulators (SERMs) were added to the experiments individually and in combination with estrogenic EDCs to interfere with potential receptor

Active control of internal transport barrier and confinement database in JT-60U reversed shear plasma

Energy Technology Data Exchange (ETDEWEB)

Sakamoto, Yoshiteru; Takizuka, Tomonori; Shirai, Hiroshi; Fujita, Takaaki; Kamada, Yutaka; Ide, Shunsuke; Fukuda, Takeshi; Koide, Yoshihiko [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

2001-07-01

Active control of internal transport barrier (ITB) and confinement properties of plasma with ITB have been studied in reversed shear plasmas. Modifications of the radial electric field (E{sub r}) profile by changing the combination of tangential neutral beams can control the ITB strength, where the contribution to E{sub r} from the toroidal rotation plays an important role. The ITB confinement database of reversed shear plasmas has been constructed. Stored energy is strongly correlated with poloidal magnetic field at the ITB foot. (author)

Optical properties of Zn{sub 1-x}Mg{sub x}Se epilayers studied by spectroscopy methods[thin films

Energy Technology Data Exchange (ETDEWEB)

Glowacki, G; Gapinski, A; Derkowska, B; Bala, W [Institute of Physics, N. Copernicus University, Torun (Poland); Sahraoui, B [Laboratoire des Proprietes Optiques des Materiaux et Applications (POMA), Universite d' Angeres, Angeres (France)

1998-07-01

Linear optical properties of Zn{sub 1-x}Mg{sub x}Se (0 {<=} x {<=} 0.4) alloys have been studied using reflectance, spectroscopic ellipsometry and photoluminescence measurements. The refractive indexes of Zn{sub 1-x}Mg{sub x}Se epilayers were investigated as a function of Mg composition (0 {<=} x {<=} 0.4). The energies of band gap E{sub g} and spin-orbit splitting E{sub g} + {delta}, have been determined. These energies are shifted gradually to higher values with increasing Mg content. (author)

Investigation of low spin resonances in the 12C+12C and 16O+12C systems

International Nuclear Information System (INIS)

Uzureau, J.L.; Fieni, J.M.; Cocu, F.; Michaudon, A.

1979-01-01

The excitation functions of the 12 C( 12 C,α) 20 Ne and 12 C( 16 O,α) 24 Mg reactions were measured at different angles below the Coulomb barrier. Resonant structures were found at Esub(cm)=5.80 MeV in the 12 C+ 12 C system and at Esub(cm)=6.10 MeV in the 16 O+ 12 C system. From the analysis of angular distributions measured at the previous resonant energies, values of respectively Jsup(π)=0 + and 2 + have been deduced [fr

The role of electron-phonon interaction and non-Gaussian transport in spectral changes of trapped electrons in glasses

International Nuclear Information System (INIS)

Funabishi, K.; Hamill, W.H.

The continuous-time-random-walk (CTRW) model which was developed for electron scavenging reactions in polar glasses is extended to the phenomenon of spectral relaxation of electrons in shallow traps esub(t) - in a wider range of systems. The central role of electron-phonon coupling in understanding the initial electron localization, the ''pre-existing trap'', and electron transfer processes are emphasized. The reactivity of esub(t) - with scavengers, including protons, is discussed in terms of the theory of multi-phonon non-radiative transitions. (author)

Approximate angular momentum projection from cranked intrinsic states

International Nuclear Information System (INIS)

Goodman, A.L.

1979-01-01

High-spin spectra are determined by approximately projecting states of good angular momentum from cranked Hartree-Fock-Bogoliubov (CHFB) wave functions. For each J the projected energy is E/sub PROJ/ approx. = E/sub CHFB/ - (ΔJ) 2 /2 J/sub CHFB/, where the moment of inertia J and the fluctuation ΔJ are spin dependent. For /sup 168,170/Yb and 174 Hf the projected J is less than the CHFB value for all J. Consequently approximate projection increases all yrast excitation energies for these nuclei

The photon tagging facility for the Crystal-Barrel/TAPS experiment at ELSA; Die Photonenmarkierungsanlage fuer das Crystal-Barrel/TAPS-Experiment an ELSA

Energy Technology Data Exchange (ETDEWEB)

Fornet-Ponse, Kathrin

2009-11-15

With the CBELASA/TAPS experiment in the framework of the SFB/TR 16 measurements of single- and double-polarization observables in the photoporoduction were performed. The energy of the high-energetic, polarized photon beams required for this, is determined by means of a so-called tagging system. In the framework of this thesis such a tagging system was constructed. It allows the energy tagging of the photons in an energy range from 0.021.E{sub 0} to 0.871.E{sub 0} with a time resolution of {sigma}=0.240 ns and an energy resolution from 0.1%.E{sub 0} to 0.4%.E{sub 0}. The reached time resolution allows to use the tagging system as time reference for the remaining experimental components. For the calculation of cross sections the knowledge of the photon flux at the experimental target is necessary. Thereby the photon definition probability P{sub {gamma}} plays a central role, which indicates, with which probability for a signal from the tagging system the corresponding photon in the {gamma} beam at the production target is present. It could be found a prescription for the determination of P{sub {gamma}}, which yields at tagging rates from 1 MHz to 10 MHz consistent results. A relative systematic error for P{sub {gamma}} was determined. Furthermore the effects of collimation and divergence of the photon beam on the number of the really in the experiment available photons and by this on the maximally reachable P{sub {gamma}} were extensively studied and experimental observations explained. [German] Mit dem CBELSA/TAPS-Experiment werden im Rahmen des SFB/TR 16 Messungen von Einfach- und Doppelpolarisationsobservablen in der Photoproduktion durchgefuehrt. Die hochenergetischen, polarisierten Photonenstrahlen werden ueber den Bremsstrahlungsprozess erzeugt. Die Energie der Photonen bestimmt sich aus der Differenz zwischen der Elektronenergie vor (E{sub 0}) und nach (E{sub e{sup -}}) dem Bremsstrahlungsprozess. Dies erfordert den Nachweis der Sekundaerelektronen mit Hilfe

Isospin effect in the (e, e'p) reaction on Zr-isotopes and others

International Nuclear Information System (INIS)

Allen, K.J.F.; Davison, A.; Thompson, M.N.

1974-01-01

A considerable amount of work concerning 90 Zr and 91 Zr has been carried out by both the Melbourne and Tohoku groups. This interest largely originated from the observance of marked structure about the giant resonance region in early (p, γ 0 ) experiments on 90 Zr. A result of these studies so far is the proposal of a weak coupling core excitation model to explain the change in character of the isotopes 90 and 91. This has been successful with one major exception -- the lack of strength about Ep=7.9 MeV in 91 Zr. In order to further test this model and possibly arrive at some explanation for the above mentioned anomaly, the obvious progression to the isotopes 92 and 94 constitutes the basic theme of the present series of experiments. For protons from 92 Zr, to determine the nature of the proton groups seen in spectra obtained with Esub(e)=30 MeV, a series of runs with Esub(e) ranging from 22.5 to 15.0 MeV were taken with the end points differing by 0.5 MeV. It should be possible to obtain the estimates of P 0 , P 1 , and possibly P 2 cross-sections from these data. As to protons from 94 Zr, although it was not possible to make the investigation as detailed as that for 92 Zr, it will be possible to establish the nature of some of the decay scheme. (Tai, I.)

High temperature elastic constant measurements: application to plutonium; Mesure des constantes elastiques a haute temperature application au plutonium

Energy Technology Data Exchange (ETDEWEB)

Bouchet, J M [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1969-03-01

We present an apparatus with which we have measured the Young's modulus and the Poisson's ratio of several compounds from the resonance frequency of cylinders in the temperature range 0 deg. C-700 deg. C. We especially studied the elastic constants of plutonium and measured for the first time to our knowledge the Young's modulus of Pu{sub {delta}} and Pu{sub {epsilon}}. E{sub {delta}} 360 deg. C = 1.6 10{sup 11} dy/cm{sup 2}; E{sub {epsilon}} 490 deg. C = 1.1 10{sup 11} dy/cm{sup 2}, {sigma}{sub {epsilon}} = 0.25 {+-} 0.03 Using our results, we have calculated the compressibility, the Debye temperature, the Grueneisen constant and the electronic specific heat of Pu{sub {epsilon}}. (author) [French] Nous decrivons un appareil qui permet de mesurer les constantes elastiques (module de Young et module de Poisson) jusqu'a 700 deg. C a partir des frequences de resonance de barreaux cylindriques. Nous avons plus specialement etudie le plutonium et determine pour la premiere fois a notre connaissance le module de Young des phases {delta} et {epsilon}: E{sub {delta}} 360 deg. C = 1.6 10{sup 11} dy/cm{sup 2}; E{sub {epsilon}} 490 deg. C = 1.1 10{sup 11} dy/cm{sup 2}, {sigma}{sub {epsilon}} = 0.25 {+-} 0.03 Nos mesures nous ont permis de calculer la compressibilite, la temperature de Debye, la constante de Gruneisen et la chaleur specifique electronique de Pu{sub {epsilon}}. (auteur)

The influence of the dynamic ergodic divertor on the radial electric field at the Tokamak TEXTOR

Energy Technology Data Exchange (ETDEWEB)

Coenen, Jan Willem

2009-11-06

In this work the influence of external Resonant Magnetic Perturbations (RMPs) on the radial electric field Er in magnetically confined plasmas is investigated by Charge Exchange Recombination Spectroscopy (CXRS) at the Tokamak TEXTOR. Here, the RMPs are produced with the Dynamic Ergodic Divertor (DED), a set of 16 helical perturbation coils located at the high field side of TEXTOR. Within this work, the base mode number of perturbations has been m/n=6/2. We have first investigated the influence of external torque from neutral heating beams on plasma rotation and E{sub r}. The ergodic zone causes an electron loss, and subsequently a (vector)j x (vector)B force driven by the compensating ion return current. In addition, the DED changes the global confinement properties. Depending on the edge safety factor (''field line twist'') q{sub a}, either increased or decreased particle confinement is observed. In case of the increased particle confinement (IPC) the increase in density (40%) and particle confinement time {tau}{sub p} (30%) is correlated to the connection of field lines at the q=5/2 surface to the DED target, locally changing the transport properties and the E{sub r}. Transport is reduced and the E{sub r} shear is increased locally at q=5/2 up to 1.5 . 10{sup 5}s{sup -1}, while the E{sub r} becomes more positive. (orig.)

New values for some 4He I 1snl energy levels, ionization energies, and Lamb shifts

International Nuclear Information System (INIS)

Martin, W.C.

1984-01-01

Recent experimental determinations of energy separations within the 1snl term system (n = 2--6) have been used to reevaluate 35 levels. Most of the levels have estimated errors less than 0.001 cm -1 relative to the 2 3 P levels. Addition of accurate theoretical term values (ionization energies) available for several 1snl levels to the corresponding experimental level values gives generally consistent values for the principal ionization energy (E/sub I/). The theoretical energies are further confirmed by the agreement of the weighted average of seven of these E/sub I/ values with a value obtained by fitting Ritz formulas to three accurately determined 1snl series; the suggested new E/sub I/ is 198 310.7745(40) cm -1 on an energy scale fixed by the value 171 135.0000 cm -1 for 2 1 P. Lamb shifts are derived for the 2, 3, 4 3 S 1 , 2 1 S 0 , 2 3 P 1 , and 2 1 P 1 levels as differences between experimental term values obtained with the new E/sub I/ and corresponding calculated term values not including Lamb shifts. The experimental and calculated values for the 1s 2 1 S 0 ground level relative to the present 1snl excited-level system are 0.00 +- 0.15 and 0.073 +- 0.009 cm -1 , respectively, so that a approx.20-fold increase in the experimental accuracy would be required to test the calculated ground-level Lamb shift

Effects of magnetic drift tangential to magnetic surfaces on neoclassical transport in non-axisymmetric plasmas

Energy Technology Data Exchange (ETDEWEB)

Matsuoka, Seikichi, E-mail: matsuoka@rist.or.jp [Research Organization for Information Science and Technology, 6F Kimec-Center Build., 1-5-2 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047 (Japan); Satake, Shinsuke; Kanno, Ryutaro [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Department of Fusion Science, SOKENDAI (The Graduate University for Advanced Studies), 322-6 Oroshi-cho, Toki 509-5292 (Japan); Sugama, Hideo [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan)

2015-07-15

In evaluating neoclassical transport by radially local simulations, the magnetic drift tangential to a flux surface is usually ignored in order to keep the phase-space volume conservation. In this paper, effect of the tangential magnetic drift on the local neoclassical transport is investigated. To retain the effect of the tangential magnetic drift in the local treatment of neoclassical transport, a new local formulation for the drift kinetic simulation is developed. The compressibility of the phase-space volume caused by the tangential magnetic drift is regarded as a source term for the drift kinetic equation, which is solved by using a two-weight δf Monte Carlo method for non-Hamiltonian system [G. Hu and J. A. Krommes, Phys. Plasmas 1, 863 (1994)]. It is demonstrated that the effect of the drift is negligible for the neoclassical transport in tokamaks. In non-axisymmetric systems, however, the tangential magnetic drift substantially changes the dependence of the neoclassical transport on the radial electric field E{sub r}. The peaked behavior of the neoclassical radial fluxes around E{sub r }={sub  }0 observed in conventional local neoclassical transport simulations is removed by taking the tangential magnetic drift into account.

Spreading of lithium on a stainless steel surface at room temperature

Energy Technology Data Exchange (ETDEWEB)

Skinner, C.H., E-mail: cskinner@pppl.gov [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States); Capece, A.M. [Princeton Plasma Physics Laboratory, Princeton, NJ 08543 (United States); Roszell, J.P.; Koel, B.E. [Department of Chemical and Biological Engineering, Princeton University, NJ 08540 (United States)

2016-01-15

Lithium conditioned plasma facing surfaces have lowered recycling and enhanced plasma performance on many fusion devices and liquid lithium plasma facing components are under consideration for future machines. A key factor in the performance of liquid lithium components is the wetting by lithium of its container. We have observed the surface spreading of lithium from a mm-scale particle to adjacent stainless steel surfaces using a scanning Auger microprobe that has elemental discrimination. The spreading of lithium occurred at room temperature (when lithium is a solid) from one location at a speed of 0.62 μm/day under ultrahigh vacuum conditions. Separate experiments using temperature programmed desorption (TPD) investigated bonding energetics between monolayer-scale films of lithium and stainless steel. While multilayer lithium desorption from stainless steel begins to occur just above 500 K (E{sub des} = 1.54 eV), sub-monolayer Li desorption occurred in a TPD peak at 942 K (E{sub des} = 2.52 eV) indicating more energetically favorable lithium-stainless steel bonding (in the absence of an oxidation layer) than lithium–lithium bonding.

Investigation of ionization losses of shower electrons in electron-photon shower developed in liquid xenon by gamma quanta in the energy range 1600-3400 MeV

International Nuclear Information System (INIS)

Okhrymenko, L.S.; Slowinski, B.; Strugalski, Z.; Sredniawa, B.

1975-01-01

Results of the investigation of differential distributions of ionization losses and the corresponding fluctuations for shower electrons in the longitudinal development of electron-photon showers produced by gamma-quanta of energies Esub(γ)=1600-3400 MeV in liquid xenon are given. A simple and convenient from the methodical point of view two-parametric function, approximating the observed distribution has been obtained. The independence of the fluctuations of ionization losses of shower electrons on the energy of gamma-quanta in the investigated interval of Esub(γ) values has been found

Some comments on flipped SU(5) times U(1) and flipped unification in general

Energy Technology Data Exchange (ETDEWEB)

Barr, S.M. (Bartol Research Institute, University of Delaware, Newark, Delaware 19716 (US))

1989-10-01

A general group-theoretical discussion of flipped embeddings is given. In addition to the well-known flipped SU(5) and flipped SO(10), the existence of flipped E{sub 6} and E{sub 7} is shown, as well as several families and special cases of flipped embeddings. A possible physical reason, essentially based on the group theory of flipped embeddings, why nature prefers the low-energy group SU(3){times}SU(2){times}U(1) to alternatives such as SU(4){times}U(1) and SU(5) is pointed out.

Angular momentum fuctuation energy in the cranking model

International Nuclear Information System (INIS)

Goodman, A.L.

1979-01-01

Angular momentum is approximately projected from Hartree-Fock-Bogoliubov cranked (HFBC) wave functions. At each J the projected energy is Esub(proj)approximately Esub(HFBC). The spin-dependent fluctuation ΔJ includes contributions from Jsub(y) and Jsub(z) as well as Jsub(x). There are no correlations in the three angular momentum components. Projected energies are calculated for 168 170 Yb and 174 Hf. When compared to experimental energies, the projected spectra are less compressed than the HFBC spectra. At low spins the projected and experimental energies are in good agreement. (Aut.)

Pulse radiolysis of 2-mercapto benzimidazole in aqueous solutions

Energy Technology Data Exchange (ETDEWEB)

Dey, G R; Naik, D B; Kishore, K; Moorthy, P N [Bhabha Atomic Research Centre, Bombay (India). Applied Chemistry Division

1994-12-31

The initial e{sub aq}{sup -}/H adducts of 2-mercapto benzimidazole(MBZ) ({lambda}{sub max} {approx} 370 nm) which are mild reductants react with parent compound to give an intermolecular 3-electron bonded species with {lambda}{sub max} at 590 nm. The rate constants for the reactions of MBZ with e{sub aq}{sup -} and OH radicals at pH 7 and with H-atoms at pH 2 were determined. OH radical reaction with MBZ gives an intramolecular 3-electron bonded species. (author). 2 refs., 2 figs., 1 tab.

Microscopic classical equations of motion calculations of high-energy heavy-ion collisions

International Nuclear Information System (INIS)

Panos, C.N.

1979-01-01

Classical microscopic nonrelativistic calculations are made for collisions between equal-mass-nuclei projectile and target with A/sub P/ = A/sub T/ = 20 for laboratory energies E/sub L/ = 117, 400, and 800 MeV/A/sub P/ and also between nuclei with A/sub P/ = A/sub T/ = 40 for E/sub L/ = 400 MeV/A/sub P/. For a given initial configuration of the projectile and target nucleons the trajectories of all nucleons are calculated classically with two-body forces between all pairs of nucleons. The implementation of the CEOM calculations is discussed in detail. More limited relativistic calculations for single initial configurations are also made. The configurations representing the initial nuclei are chosen to have a reasonable radius and kinetic energy; however, they do not saturate with the two-body potentials used. The trajectory information is analyzed to give a large number of position and momentum dependent quantities such as densities, rapidity distributions, inclusive double differential cross sections, etc. The results show that a central collision (b = 0) proceeds in three stages, an initial transparent stage, a strongly interacting stage where the dissipation is large, and finally an expansion stage for which there is considerable dissipation. Appreciable potential energy effects were found for b = 0; however, the final distributions were very similar for the scattering equivalent potentials. For lower energies (E/sub L/ approx. = 100 MeV) there is some evidence of fusion into large fragments. The thermal models for b = 0 are tested. Noncentral collisions show typical nonequilibrium and transparency features. The multiplicity distribution is obtained for A/sub P/ = A/sub T/ = 20 and E/sub L/ = 800 MeV. A comparison of the impact parameter-integrated inclusive double differential cross sections is made with the experimental data for A/sub P/ = A/sub T/ = 20, E/sub L/ = 800 MeV and shows fair agreement

Structure of 14C via elastic and inelastic neutron scattering from 13C: Measurement, R-matrix analysis, and shell model calculations

International Nuclear Information System (INIS)

Resler, D.A.

1987-03-01

The specific purpose of this work is to provide a better understanding of the 14 C level structure; the general purpose is to provide the details for using shell model calculations in R-matrix analyses. Using the TOF facilities of the Ohio University Accelerator Laboratory, the elastic and first 3 inelastic differential scattering cross sections for 13 C + n were measured at 69 energies for 4.5 ≤ E/sub n/ ≤ 11 MeV. A multiple scattering code was developed which provided a simulation of the experimental scattering process allowing accurate corrections to the small inelastic data. The integrated 13 C(n,α) 10 Be cross section is estimated. The sequential 2n-decay of 14 C states populated by 13 C + n was observed. A shell model code was developed. Normal and nonnormal parity calculations were made for the lithium isotopes using a new two-body interaction. The results for 5 Li predict the 2s/sub 1/2/ and 1d/sub 5/2/ single-particle states to be located below the 3/2 + state. Similar calculations were made for 13 C, 13 N, and 14 C. Results for 13 C and 13 N show for E/sub x/ 7 Li and 14 C, 2 h-barω calculations were done. Shell model calculations generated the R-matrix parameters for the elastic and first 3 inelastic channels of 13 C + n. After adjusting some energies, the predicted structure generally agrees with experiment for E/sub n/ 13 C + n data were refit to replace R 0 background terms by more realistic broad states and to get better agreement with model calculations. R-matrix fitting of the full data set produced new 14 C level information. For E/sub n/ > 4 MeV (E/sub x/ > 12 MeV), 5 states are given definite J/sup π/ assignments; 3, tentative assignments. 122 refs., 91 figs., 30 tabs

Enhancment of ferromagnetism in Ba and Er co-doped BiFeO{sub 3} nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Naeimi, A.S., E-mail: naeimi.a.s@gmail.com [Department of Physics, Aliabad Katoul Branch, Islamic Azad University, Aliabad Katoul (Iran, Islamic Republic of); Dehghan, E.; Sanavi Khoshnoud, D. [Department of Physics, Semnan University, Semnan 35195-363 (Iran, Islamic Republic of); Gholizadeh, A. [School of Physics, Damghan University (DU), Damghan (Iran, Islamic Republic of)

2015-11-01

Bi{sub 1−y−x}Ba{sub y}Er{sub x}FeO{sub 3} [BB{sub y}E{sub x}FO, (0.13≤y≤0.17, 0≤x≤0.2)] nanoparticles were successfully synthesized by a sol–gel method. The structural, microstructural and magnetic properties have been investigated, using X-ray diffraction, Raman scattering, field emission scanning electron microscopy (FE-SEM) and magnetometry measurements at room temperature. The refinement of X-ray diffraction pattern of BB{sub 0.15}E{sub 0}FO indicates a phase transition from rhombohedral (R3c) to tetragonal (P4mm) with increasing Ba content and a transition from the coexistence of rhombohedral–tetragonal phase to orthorhombic (Pbnm) in BB{sub 0.15}E{sub x}FO samples with increasing Er concentration. The Raman analysis confirms crystal phase transition in BB{sub 0.15}E{sub x}FO compounds. The FE-SEM and TEM analysis show that the average nanoparticle size is about 50–100 nm and it decreases with Er concentration. The remnant magnetisation of BB{sub 0.15}E{sub 0.1}FO sample (M{sub r}=0.98 emu/g) is approximately two times greater than compared to BB{sub 0.15}E{sub 0}FO (M{sub r}=0.51 emu/g) that may be attributed to the collapse of spin structure and modifying exchange interactions because of Er{sup +3} doping. This enhancement in magnetic properties at room temperature can play an important role for the practical applications. - Highlights: • Bi{sub 1−y−x}Ba{sub y}Er{sub x}FeO{sub 3} nanoparticles were successfully synthesized by a sol–gel route. • X-ray diffraction and Raman spectroscopy measurements confirmed a phase transition from rhombohedral–orthorhombic. • Considerable enhancement in magnetisation of BiFeO{sub 3} is obtained with Ba and Er co-doping.

Shear wave elastography of thyroid nodules for the prediction of malignancy in a large scale study

Energy Technology Data Exchange (ETDEWEB)

Park, Ah Young; Son, Eun Ju [Department of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of); Han, Kyunghwa [Biostatistics Collaboration Unit, Gangnam Medical Research Center, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of); Youk, Ji Hyun [Department of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of); Kim, Jeong-Ah, E-mail: chrismd@hanmail.net [Department of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of); Park, Cheong Soo [Department of Surgery, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of)

2015-03-15

Highlights: •Elasticity indices of malignant thyroid nodules were higher than those of benign. •High elasticity indices were the independent predictors of thyroid malignancy. •SWE evaluation could be useful as adjunctive tool for thyroid cancer diagnosis. -- Abstract: Objectives: The purpose of this study is to validate the usefulness of shear wave elastography (SWE) in predicting thyroid malignancy with a large-scale quantitative SWE data. Methods: This restrospective study included 476 thyroid nodules in 453 patients who underwent gray-scale US and SWE before US-guided fine-needle aspiration biopsy (US-FNA) or surgical excision were included. Gray-scale findings and SWE elasticity indices (EIs) were retrospectively reviewed and compared between benign and malignant thyroid nodules. The optimal cut-off values of EIs for predicting malignancy were determined. The diagnostic performances of gray-scale US and SWE for predicting malignancy were analyzed. The diagnostic performance was compared between the gray-scale US findings only and the combined use of gray-scale US findings with SWEs. Results: All EIs of malignant thyroid nodules were significantly higher than those of benign nodules (p ≤ .001). The optimal cut-off value of each EI for predicting malignancy was 85.2 kPa of E{sub mean}, 94.0 kPa of E{sub max}, 54.0 kPa of E{sub min}. E{sub mean} (OR 3.071, p = .005) and E{sub max} (OR 3.015, p = .003) were the independent predictors of thyroid malignancy. Combined use of gray-scale US findings and each EI showed elevated sensitivity (95.0–95.5% vs 92.9%, p ≤ .005) and AUC (0.820–0.834 vs 0.769, p ≤ .005) for predicting malignancy, compared with the use of only gray-scale US findings. Conclusions: Quantitative parameters of SWE were the independent predictors of thyroid malignancy and SWE evaluation combined with gray-scale US was adjunctive to the diagnostic performance of gray-scale US for predicting thyroid malignancy.

Self-Absorption Studies with a 4 {pi} {beta}-Proportional Flow Counter; Etudes sur l'autoabsorption avec un compteur {beta} 4 {pi} proportionnel a courant; Izuchenie samopogloshcheniya pri pomoshchi {beta} proportsional'no-potochnogo 4 {pi} schetchika; Estudios sobre autoabsorcion con un contador de flujo proporcional {beta}4 {pi}

Energy Technology Data Exchange (ETDEWEB)

Yaffe, L; Fishman, J B [Radiochemistry Laboratory, Dept. of Chemistry, McGill University, Montreal, Quebec (Canada)

1960-06-15

Self-absorption studies of {beta} emitters have been made by means of the techniques outlined by Pate and Yaffe [Can. J. Chem. 34, 265 (1956)]. Volatile compounds of H''3, C''1''4, Co''6''0, Hg''2''0''3, As''7''7, and P{sup 32} (E{sub max} ranging from 0.018 to 1.7 MeV) were distilled on to thin VYNS mounts and the self-absorption characteristics determined. An empirically determined series of curves relating E{sub max}, source thickness, and self-absorption is given. The self-absorption data have been subjected to a theoretical analysis for counters of small angle and 4{pi} geometry. The experimentally determined self-absorption curves for 4 {pi} geometry lie in between the theoretical small angles and 4 {pi} geometry curves. (author) [French] Des etudes sur l'autoabsorption des emetteurs {beta} ont ete faites selon les techniques indiquees par Pate and Yaffe [Can. J. Chem. 34, 265 (1956)]. Des composes volatils de H{sup 3}, S{sup 14}, Co{sup 60}, Hg{sup 203}, As{sup 77} et P{sup 32} (E{sub max} allant de 0,018 a 1,7 MeV), ont ete recueillis par distillation sur des supports minces en resine vynilique (VYNS) et les caracteristiques de l'autoabsorption ont ete determinees. Le memoire contient une serie de courbes determinees empiriquement, qui donnent les relations entre E{sub max} l'epaisseur de la source et l'autoabsorption . Les donnees sur l'autoabsorption ont fait l'objet d'une analyse theorique pour les compteurs a geometrie de petit angle solide et 4 {pi}. Les courbes d'auto- absorption determinees experimentalemen t pour la geometrie 4 {pi} sont comprises entre les courbes theoriques correspondant a la geometrie de petit angle solide et a la geometrie 4 {pi}. (author) [Spanish] Les autores han estudiado la autoabsorcion de los emisores {beta} utilizando las tecnicas descritas por Pate y Yaffe [Can. J. Chem. 34, 265 (1956)]. Han destilado compuestos volatiles de H{sup 3}, S{sup 14}, So{sup 60}, Hg{sup 203}, As{sup 77} y P{sup 32} (E{sub max} comprendida

The Prompt-afterglow Connection in Gamma-ray Bursts: a Comprehensive Statistical Analysis of Swift X-ray Light-curves

Science.gov (United States)

Margutti, R.; Zaninoni, E.; Bernardini, M. G.; Chincarini, G.; Pasotti, F.; Guidorzi, C.; Angelini, Lorella; Burrows, D. N.; Capalbi, M.; Evans, P. A.;

Polarized proton capture reaction /sup 7/Li(p,. gamma. )/sup 8/Be in the energy range from 380 to 960 keV

Energy Technology Data Exchange (ETDEWEB)

Ulbricht, J; Arnold, W; Berg, H; Huttel, E; Krause, H H; Clausnitzer, G [Giessen Univ. (Germany, F.R.). Abt. Grossgeraete (Angewandte Kernphysik)

1977-09-05

The polarized proton capture in /sup 7/Li was used to study the reaction mechanism and to obtain spectroscopic information on the /sup 8/Be nucleus. Gamma-ray angular distributions of the analyzing power were measured as a function of proton energy from Esub(p) = 380-960 keV with three Ge(Li) detectors simultaneously. The excitation functions of the cross section and the analyzing power are strongly energy dependent. The data were analyzed unambiguously and represented by three R-matrix elements, two M1 and one E1. The energy dependence of the two M1 matrix elements agrees with the well-known two 1/sup +/ resonances at Esub(x) = 17.642 and 18.157 MeV. The energy dependence of the E1 matrix element shows a smooth background presumably caused by a direct-capture mechanism, and furthermore, a resonant contribution, which is a significant suggestion of a new 1/sup -/ state in the /sup 8/Be system at Esub(x) = 17.70 MeV with a width of GAMMAsub(p) = 180 keV.

Auger recombination in p-type InAs and in Gasub(x)Insub(1-x)As solid solutions

International Nuclear Information System (INIS)

Zotova, N.V.; Yassievich, I.N.

1977-01-01

The probability of the Auger recombination in p-type semiconductors, which is accompanied by transition of the second hole into the zone, splitted by spin-orbital interaction, was calculated. The above process is effective when the energy of spin-orbital splitting off Δ is close to the forbidden zone energy Esub(g), which takes place in the case of InAs, GaSb and solid solutions based on these compounds. The calculation is performed for the non-degenerate hole gas at a finite difference of Esub(g) - Δ. By means of the study of radiative recombination in InAs and Gasub(x)Insub(1-x)As solid solutions with small contents of GaAs (0 17 cm -3 . It is found that the quantum yield of radiative recombination increases sharply in Gasub(x)Insub(1-x)As solid solutions with the increase of x, which is associated with the increase of the difference of Esub(g) - Δ; the radiative recombination intensity increases in correspondence with the theoretical calculation made

Study of the effect of the deposition parameters on the structural, electric and optical characteristics of polymorphous silicon films prepared by low frequency PECVD

Energy Technology Data Exchange (ETDEWEB)

Moreno, M., E-mail: mmoreno@inaoep.mx [Instituto Nacional de Astrofisica, Optica y Electronica, INAOE, Puebla (Mexico); Torres, A. [Instituto Nacional de Astrofisica, Optica y Electronica, INAOE, Puebla (Mexico); Ambrosio, R. [Universidad Autonoma de Ciudad Juarez, Electrical Deparment, Chihuahua (Mexico); Zuniga, C.; Torres-Rios, A.; Monfil, K.; Rosales, P.; Itzmoyotl, A. [Instituto Nacional de Astrofisica, Optica y Electronica, INAOE, Puebla (Mexico)

2011-10-25

In this work we present our results on the deposition and characterization of polymorphous silicon (pm-Si:H) films prepared by low frequency plasma enhanced chemical vapor deposition (LF-PECVD). We have studied the effect of the plasma deposition parameters (as the chamber pressure and gas flow rates of SiH{sub 4} and H{sub 2}) on the structural, electric, and optical characteristics of the films. The temperature dependence of conductivity ({sigma}(T)), activation energy (E{sub a}), optical band gap (E{sub g}) and deposition rate (V{sub d}) were extracted for pm-Si:H films deposited at different pressure values and different gas flow rates. We observed that the chamber pressure is an important parameter that has a significant effect on the electric characteristics, and as well on the morphology of the pm-Si:H films (deduced from atomic force microscopy). It was found an optimal pressure range, in order to produce pm-Si:H films with high E{sub a} and room temperature conductivity, {sigma}{sub RT}, which are key parameters for thermal detection applications.

FY08 parameters for the injection, acceleration, and extraction of gold ions and deuterons in the booster, AGS, and RHIC

Energy Technology Data Exchange (ETDEWEB)

Gardner, C.J.

2010-08-01

A Gold ion with charge eQ has N = 197 Nucleons, Z = 79 Protons, and (Z-Q) electrons. (Here Q is an integer and e is the charge of a single proton.) The mass is m = au - Qm{sub e} + E{sub b}/c{sup 2} (1) where a = 196.966552 is the relative atomic mass [1, 2] of the neutral Gold atom, u = 931.494013 MeV/c{sup 2} is the unified atomic mass unit [3], and m{sub e}c{sup 2} = .510998902 MeV is the electron mass [3]. E{sub b} is the binding energy of the Q electrons removed from the neutral Gold atom. This amounts to 0.332 MeV for the helium-like gold ion (Q = 77) and 0.517 MeV for the fully stripped ion. For the Au{sup 31+} ion we have E{sub b} = 13.5 keV. These numbers are given in Ref. [4]. The deuteron mass [3] is 1875.612762(75) MeV/c{sup 2}.

Sex-dependent differences in phenobarbitane-induced oestradiol-2-hydroxylase activity in rat liver

Energy Technology Data Exchange (ETDEWEB)

Theron, C.N.; Neethling, A.C.; Taljaard, J.J.F. (Stellenbosch Univ. (South Africa). Dept. of Chemical Pathology)

1981-08-15

Oestradiol-2-hydroxylase (E/sub 2/-OH) activity was measured in liver and brain microsomes of 6-8-week-old Wistar rats. Phenobarbitone (75 mg/kg daily for 3 days) significantly increased enzyme activity in the liver of males and females, but there were striking differences between the two sexes. In males the enzyme activity was increased by 37% over control values and in females by 200%. The total microsomol cytochrome P-450 content was increased by 75% in males and by 82% in females. The apparent Michaelis constant (K(m)) of E/sub 2/-OH for 17..beta..-oestradiol in untreated males (9,8 ..mu..M) and females (9,2 ..mu..M) did not differ significantly. Phenobarbitone treatment, however, tended to reduce the apparent K(m) in males (8,2 ..mu..M) and to increase it in females (18,7 ..mu..M). E/sub 2/-OH activity was also detected in brain tissue of both sexes, but it was 50-200-fold lower than in the liver and was not increased by phenobarbitone.

Gamma-irradiation effects on optical properties of lexan film. Vol. 2

Energy Technology Data Exchange (ETDEWEB)

Abd-Elrehim, N; El-Samahy, A E; Kassem, M E [Physics Department, Faculty of Science, Alexandria University. (Egypt); Abou-Taleb, W M [Physics and Chemistry Department, Faculty of Education, Alexandria University. (Egypt)

1996-03-01

The optical absorption method is a powerful tool for studying the optically induced transitions and for determining the energy gap in crystalline and non-crystalline materials. The absorption spectra in the lower energy part sheds light on the atomic vibrations. While the higher energy parts of the spectrum manifest the electronic states in the atoms. Effect of gamma-irradiation on the optical properties of plastic detector (Lexan film) has been studied. These investigations were carried out for gamma-doses from 10 kGy -2 mGy to determine the optical parameters; optical energy gap E{sub op}, absorption coefficient {alpha} , absorption index K, mobility energy gap E{sub g}, absorption band edge {lambda}{sub g} and the absorbance at wavelength 340 nm. The results showed that both direct and indirect transitions existed in lexan detector, and because highly sensitive to gamma-irradiation doses. The variations of optical energy gap with gamma-irradiation doses can be explained as the change in the degree of disorder and the phonon energy E{sub p}, is dose dependent. 7 figs.

Effect of impact energy on damage resistance and mechanical property of C/SiC composites under low velocity impact

Energy Technology Data Exchange (ETDEWEB)

Mei, Hui, E-mail: phdhuimei@yahoo.com; Yu, Changkui; Xu, Yawei; Han, Daoyang; Cheng, Laifei

2017-02-27

The present study investigated the damage resistance of two dimensional carbon fiber reinforced silicon carbide (C/SiCs) composites subjected to low velocity impact (LVI). Damage microstructures of specimens under different impact energies (E{sub i}) were characterized by infrared thermography, X-ray computed tomography and scanning electron microscopy. The real damage radii of specimens were found to change slightly with E{sub i}, whereas apparent damage radii where much larger. Overall, the fabricated 2D C/SiC composites exhibited good damage resistance to LVI with nominal post-impact tensile strengths remaining at 89.4%, 83.35%, 76.97%, and 74.84% of their pre-impacted counterpart of 158 MPa, for impact energies of 3, 4, 5, and 6 J, respectively. Compared with the as-received one, after LVI real tensile strengths of the C/SiC composite specimens increased by 5.84% for the E{sub i} of 3 J, 9.27% for 4 J, −1.83% for 5 J, −3.16% for 6 J.

Seizure-induced alterations in fast-spiking basket cell GABA currents modulate frequency and coherence of gamma oscillation in network simulations

Energy Technology Data Exchange (ETDEWEB)

Proddutur, Archana; Yu, Jiandong; Elgammal, Fatima S. [Department of Neurology and Neurosciences, New Jersey Medical School, Rutgers, Newark, New Jersey 07103 (United States); Santhakumar, Vijayalakshmi, E-mail: santhavi@njms.rutgers.edu [Department of Neurology and Neurosciences, New Jersey Medical School, Rutgers, Newark, New Jersey 07103 (United States); Department of Pharmacology and Physiology, New Jersey Medical School, Rutgers, Newark, New Jersey 07103 (United States)

2013-12-15

Gamma frequency oscillations have been proposed to contribute to memory formation and retrieval. Fast-spiking basket cells (FS-BCs) are known to underlie development of gamma oscillations. Fast, high amplitude GABA synapses and gap junctions have been suggested to contribute to gamma oscillations in FS-BC networks. Recently, we identified that, apart from GABAergic synapses, FS-BCs in the hippocampal dentate gyrus have GABAergic currents mediated by extrasynaptic receptors. Our experimental studies demonstrated two specific changes in FS-BC GABA currents following experimental seizures [Yu et al., J. Neurophysiol. 109, 1746 (2013)]: increase in the magnitude of extrasynaptic (tonic) GABA currents and a depolarizing shift in GABA reversal potential (E{sub GABA}). Here, we use homogeneous networks of a biophysically based model of FS-BCs to examine how the presence of extrasynaptic GABA conductance (g{sub GABA-extra}) and experimentally identified, seizure-induced changes in g{sub GABA-extra} and E{sub GABA} influence network activity. Networks of FS-BCs interconnected by fast GABAergic synapses developed synchronous firing in the dentate gamma frequency range (40–100 Hz). Systematic investigation revealed that the biologically realistic range of 30 to 40 connections between FS-BCs resulted in greater coherence in the gamma frequency range when networks were activated by Poisson-distributed dendritic synaptic inputs rather than by homogeneous somatic current injections, which were balanced for FS-BC firing frequency in unconnected networks. Distance-dependent conduction delay enhanced coherence in networks with 30–40 FS-BC interconnections while inclusion of gap junctional conductance had a modest effect on coherence. In networks activated by somatic current injections resulting in heterogeneous FS-BC firing, increasing g{sub GABA-extra} reduced the frequency and coherence of FS-BC firing when E{sub GABA} was shunting (−74 mV), but failed to alter average

Piezoelectric response of a PZT thin film to magnetic fields from permanent magnet and coil combination

Energy Technology Data Exchange (ETDEWEB)

Guiffard, B.; Seveno, R. [Universite de Nantes, Lunam Universite, IETR UMR CNRS 6164, Nantes (France)

2014-07-10

In this study, we report the magnetically induced electric field E{sub 3} in Pb(Zr{sub 0.57}Ti{sub 0.43})O{sub 3} (PZT) thin films, when they are subjected to both dynamic magnetic induction (magnitude B{sub ac} at 45 kHz) and static magnetic induction (B{sub dc}) generated by a coil and a single permanent magnet, respectively. It is found that highest sensitivity to B{sub dc} - Δ vertical stroke E{sub 3} vertical stroke ΔB{sub dc} - is achieved for the thin film with largest effective electrode. This magnetoelectric (ME) effect is interpreted in terms of coupling between eddy current-induced Lorentz forces (stress) in the electrodes of PZT and piezoelectricity. Such coupling was evidenced by convenient modelling of experimental variations of electric field magnitude with both B{sub ac} and B{sub dc} induction magnitudes, providing imperfect open circuit condition was considered. Phase angle of E{sub 3} versus B{sub dc} could also be modelled. At last, the results show that similar to multilayered piezoelectric-magnetostrictive composite film, a PZT thin film made with a simple manufacturing process can behave as a static or dynamic magnetic field sensor. In this latter case, a large ME voltage coefficient of α = vertical stroke E{sub 3} vertical stroke /B{sub ac} = 3.55 V/cm Oe under B{sub dc} = 0.3 T was found. All these results may provide promising low-cost magnetic energy harvesting applications with microsized systems. (orig.)

First-principles study on mono-vacancy self diffusion and recovery in tungsten crystal

Energy Technology Data Exchange (ETDEWEB)

Wen, Shu long [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China); Chen, Ji ming; Liu, Xiang [Fusion Science of Southwestern Institute of Physics, Chengdu, Sichuan 610041 (China); Zhu, Hao; Chang, Hong yan [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China); Huang, Zheng, E-mail: zhhuang@swjtu.edu.cn [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China); Pan, Min, E-mail: mpan@swjtu.edu.cn [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China); Western Superconducting Technologies Co., Ltd., Xi’an, Shanxi 710018 (China); Zhao, Yong [Key Laboratory of Advanced Technology of Materials (Ministry of Education), Superconductivity and New Energy R& D Ceter, Southwest JiaoTong University, Chengdu, Sichuan 610031 (China)

2016-11-01

Highlights: • The migration barrier energy E{sub m} of vacancy indicated that the optimum diffusion paths would exist in the diffusion process. • The Frenkel pair’s recovery had a close correlation with the “I–V” distance and within a range of 1.86–2.08 eV. • The self-recovery region has an ellipsoid profile with the semiminor axis of 2.7 Å and the semimajor axis of 5.5 Å. • The probability for the vacancy migration was closely assosiated with the E{sub m} and the working temperature. - Abstract: The point defects behavior becomes one of the most basic issues under the challenge of fusion environment. The recovery mechanisms of Frenkel pair defects and the self-diffusion coefficient of mono-vacancy in bulk bcc tungsten were researched by the first principle calculations. The calculation of migration energy curves for <111> SIAs indicated that the process of the Frenkel pair recovery had a close correlation with the “I–V” distance, and the migration barrier energies E{sub m} was within a limit range of 1.86–2.08 eV. It was found that the self-recovery region had an ellipsoid profile with the semiminor axis of 2.7 Å and the semimajor axis of 5.5 Å. The self-diffusion coefficients of the mono-vacancy were calculated and the results showed that the probability for the vacancy migration was not only associated with the E{sub m} but also the temperature being challenged.

Study of relativistic nucleus-nucleus collisions at the CERN SPS

International Nuclear Information System (INIS)

Albrecht, R.; Bock, R.; Claesson, G.; Gutbrod, H.H.; Kolb, B.; Schmidt, R.; Schulze, R.; Doss, M.; Kristiansson, P.; Poskanzer, A.M.; Ritter, H.G.; Garpmann, S.; Gustafsson, H.A.; Oskarsson, A.; Otterlund, I.; Persson, S.; Soderstrom, K.; Stenlund, E.; Beckmann, P.; Berger, F.; Dragon, L.; Glasow, R.; Kampert, K.H.; Loehner, H.; Peitzmann, T.; Purschke, M.; Santo, R.; Wienke, R.; Awes, T.; Baktash, C.; Beene, J.; Ferguson, R.; Gross, E.; Johnson, J.; Lee, I.Y.; Obenshain, F.; Plasil, F.; Young, G.; Sorensen, S.; Siemiarczuk, T.; Stepaniak, Y.; Zielinski, I.

1985-08-01

In this experiment the physics at high energy densities will be explored. High energy densities are expected in collisions of 16 O (provided from the GSI-LBL light ion source) with large target nuclei. One expectation is a phase transition into the quark gluon plasma. The experiment consists of a vertex detector, called the Plastic Ball, electromagnetic Pb-glass calorimeter, a EM-Hadron Calorimeter Wall, a multiplicity detector for charged particles and a zero degree calorimeter. The Plastic Ball consists of a 655 module, double dE/dx scintillator sphere covering THETAsub(Lab)>30 0 , thus identifying protons, deuterons, tritons, alphas, etc., in the target rapidity domain. THETA 0 are covered by a streamer tube, pad readout array (25000 pads), and by 6 m 2 Pb-Fe electromagnetic/hadronic fine granularity calorimeter following the Fabjan Willis tower design. A 1350-segment, GAMS type lead glass calorimeter of sufficiently small granularity to identify π 0 and direct photons at Esub(perpendicular to)>1 GeV covers the 40 0 -90 0 cm angles. This experiment can be triggered on projectile energy loss high Esub(t), high Msub(ch) or on high Esub(t) and large e-m energy in the lead glass. Overall, it determines the energy flux and Esub(t) distribution, the high psup(perpendicular to) π 0 and γ distribution near mid-rapidity, and the target spectator decay pattern and entropy (from the relative yields of p, d, t...), as well as multiplicity distribution and multiplicity fluctuations. (orig.)

Multicolor tunable emission induced by Cu ion doping of perovskite zirconate

Energy Technology Data Exchange (ETDEWEB)

Lee, D.J. [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Lee, Y.S., E-mail: ylee@ssu.ac.kr [Department of Physics, Soongsil University, Seoul 156-743 (Korea, Republic of); Noh, H.-J. [Department of Physics, Chonnam National University, Gwangju 500-757 (Korea, Republic of)

2016-01-15

We report on a multicolor tunable emission induced by Cu ion doping of perovskite zirconate SrZrO{sub 3} with a fairly large bandgap (5.6 eV). X-ray photoelectron spectroscopy of our samples revealed the existence of two mixed valence states of the doped Cu ions, +1 and +2, with a ratio of 3:1. In photoluminescence excitation spectroscopy the absorption structures of the 3d states in monovalent Cu{sup +} and divalent Cu{sup 2+} were identified near 5 eV and 3.5 eV, respectively. Interestingly, in relation to the valence states of the Cu ions, the emission spectra depended strongly on the photo-excitation energy (E{sub ex}). For E{sub ex}<3.8 eV (UVA) two orange and green emissions were observed with the involvement of the Cu{sup 2+} state. For E{sub ex}>3.8 eV (UVB/UVC), however, the Cu{sup +} state, instead of the Cu{sup 2+} state, was dominant in the emission process, causing the visible emission to be turned into violet. Our results were indicative of the complementary role of the different Cu-ion valence states in a wide range of visible emission with respect to E{sub ex}. - Highlights: • Visible emission induced by the Cu doping of SrZrO3. • Tunable colors from orange to violet with respect to the photo-excitation energy. • Multicolor emission should be related to the mixed valence states of the doped Cu ions.

Nonlinear spectroscopy of the Rydberg atoms

International Nuclear Information System (INIS)

Delone, N.B.; Krajnov, V.P.; Shepelyanskij, D.L.

1984-01-01

The results of investigation into perturbation of Rydberg states (RS) of atoms in an outer alternating field (OAF) are discussed. Both highly excited states of hydrogen atom at the energy Esub(n)=-1/2n -2 (n>>1 - basic quantum number) and excited states of compound atoms with energy Esub(nl)=-1/2(n*) -2 where n*=n-delta sub(e)-effective basic quantum number, delta sub(e)-quantum defect, are implied by RS. Perturbation of atomic state in the OAF is determined not only by field strength E, but by its frequency ω as well. During OAF inclusion the initial state Esub(lambda) transits to quasienergetic at the energy Esub(lambda)(E)+-kω, where K=0, +-1, +-2, .... Solutions of the problem of quasienergetic level population is obtained only for some simple particular cases. A simple case, when a real multilevel atom is replaced by a model system comprising one bound electron state with the basic quantum number n-model of the insulated level (MIL) is considered. Conditions of MIL applicability are discussed. Estimation of critical OAF strength at which MIL approximation becomes faulty are discussed. It is stated that any consideration of RS perturbation in OAF claiming to exceeding MIL frames should comprise consideration of ionization processes. If one keeps to the frames of OAF; the strength of which is lower than the determined critical values then MIL is true and use of this model permits to correctly describe the main features of RS perturbation in an alternating field

Study of the (d,α) reactions on the nuclei 10B, 11B, 12C, and 13C and the reaction 13C(p,α)10B and their microscopic and semicroscopic analysis

International Nuclear Information System (INIS)

Abd el-Kariem, S.E.S.

1984-01-01

In the framework of a systematic analysis of many-particle transfer reactions on light nuclei in the present thesis the two-particle transfer reactions of the type (d,α) on the nucleus 10 B at Esub(d) = 16 MeV and on the nuclei 11 B, 12 C and 13 C at Esub(d) = 24 MeV as well as the three-particle transfer reaction 13 C(p,α) 10 B at eight incident energies between 16 and 45 MeV have been studied. In the case of the residual nuclei 10 B and 11 B transitions up to an excitation energy Esub(x) approx.= 7.5 respectively approx.= 9,0 MeV, in the case of the residual nuclei 8 Be and 9 Be transitions up to Esub(x) approx.= 17 respectively 2.5 MeV were evaluated. Under the assumption that the studied reactions behave as direct one-stage transfer processes the measurement results were analyzed in the framework of the DWBA theory in zero-range approximation. The parameters for the optical potentials used in the DWBA calculations were taken from literature and partly modified by fitting to the angular distributions of the reactions studied here. Microscopic and semimicroscopic calculations were performed. In the semimicroscopic calculations the spectroscopic amplitudes calculated microscopically or in SU(3) approximation were used together with a cluster form factor, in the other case with a microscopically calculated form factor. For the residual nucleus for some higher excited states results on spin, parity, and isospin could be partly obtained, partly confirmed. (orig./HSI) [de

Electrocatalytic oxidation of deferiprone and its determination on a carbon nanotube-modified glassy carbon electrode

Energy Technology Data Exchange (ETDEWEB)

Yadegari, H. [Department of Chemistry, Faculty of Science, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran (Iran, Islamic Republic of); Jabbari, A. [Department of Chemistry, Faculty of Science, K.N. Toosi University of Technology, P.O. Box 16315-1618, Tehran (Iran, Islamic Republic of)], E-mail: jabbari@kntu.ac.ir; Heli, H.; Moosavi-Movahedi, A.A. [Institute of Biochemistry and Biophysics, University of Tehran, Tehran (Iran, Islamic Republic of); Karimian, K. [Arasto Pharmaceutical Chemicals Inc., Tehran (Iran, Islamic Republic of); Khodadadi, A. [Department of Chemical Engineering, Faculty of Engineering, University of Tehran, Tehran (Iran, Islamic Republic of)

2008-02-15

The electrochemical behavior of the anti-thalassemia and anti-HIV replication drug, deferiprone, was investigated on a carbon nanotube-modified glassy carbon (GC-CNT) electrode in phosphate buffer solution, pH 7.40 (PBS). During oxidation of deferiprone, two irreversible anodic peaks, with E{sub 1}{sup 0}=452 and E{sub 2}{sup 0}=906mV, appeared, using GC-CNT. Cyclic voltammetric study indicated that the oxidation process is irreversible and diffusion controlled. The number of exchanged electrons in the electro-oxidation process was obtained, and the data indicated that deferiprone is oxidized via two two-electron steps. The results revealed that carbon nanotube (CNT) promotes the rate of oxidation by increasing the peak current, so that deferiprone is oxidized at lower potentials, which thermodynamically is more favorable. This result was confirmed by impedance measurements. The diffusion coefficient, electron-transfer coefficient and heterogeneous electron-transfer rate constant of deferiprone were found to be 1.49 x 10{sup -6} cm{sup 2} s{sup -1}, 0.44, and 3.83 x 10{sup -3} cm s{sup -1}, respectively. A sensitive, simple and time-saving differential-pulse voltammetric procedure was developed for the analysis of deferiprone. Using the proposed method, deferiprone can be determined with a detection limit of 5.25 x 10{sup -7} M. The applicability of the method to direct assays of spiked human serum and urine fluids is described.

n/p-Type changeable semiconductor TiO{sub 2} prepared from NTA

Energy Technology Data Exchange (ETDEWEB)

Li Qiuye; Wang Xiaodong; Jin Zhensheng, E-mail: zhenshengjin@henu.edu.cn; Yang Dagang; Zhang Shunli; Guo Xinyong; Yang Jianjun; Zhang Zhijun [Henan University, Key Laboratory of Special Functional Materials (China)

2007-10-15

A novel kind of nano-sized TiO{sub 2} (anatase) was obtained by high-temperature (400-700 deg. C) dehydration of nanotube titanic acid (H{sub 2}Ti{sub 2}O{sub 4}(OH){sub 2}, NTA). The high-temperature (400-700 deg. C) dehydrated nanotube titanic acids (HD-NTAs) with a unique defect structure exhibited a p-type semiconductor behavior under visible-light irradiation ({lambda}{>=} 420nm, E{sub photon}=2.95 eV), whereas exhibited an n-type semiconductor behavior irradiated with UV light ({lambda}{>=} 365nm, E{sub photon}=3.40 eV)

Exchange reaction between hydrogen and deuterium. I. Importance of surface reactions in the steady-state mechanism

Energy Technology Data Exchange (ETDEWEB)

Marteau, C; Gaillard-Cusin, F; James, H [Centre National de la Recherche Scientifique, 45 - Orleans-la-Source (France). Centre de Recherches sur la Chimie de Combustion et des Hautes Temperatures

1978-05-01

Investigation of heterogeneous initiation process of gas phase linear chain reactions is carried out through the study of H/sub 2/-D/sub 2/ exchange reaction. Experimental data under study concern mainly the stationary rate of HD formation and the prestationary proceeding. Steady-state method accounts for the first one of these data; it allows to clearly compare the wall process part to the part played by the homogeneous chain reaction towards HD formation. Activation energy of exchange elementary step between chemisorbed hydrogen (on silica) and gaseous deuterium has been evaluated: Esub(e1)=52+-1 Kcal/mole.

Distinguishing between SU(5) and flipped SU(5)

Energy Technology Data Exchange (ETDEWEB)

Dorsner, Ilja [Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34014 Trieste (Italy); Fileviez Perez, Pavel [Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34014 Trieste (Italy) and Pontificia Universidad Catolica de Chile, Facultad de Fisica, Casilla 306, Santiago 22 (Chile)]. E-mail: fileviez@higgs.fis.puc.cl

2005-01-13

We study in detail the d=6 operators for proton decay in the two possible matter unification scenarios based on SU(5) gauge symmetry. We investigate the way to distinguish between these two scenarios. The dependence of the branching ratios for the two body decays on the fermion mixing is presented in both cases. We point out the possibility to make a clear test of flipped SU(5) through the decay channel p->{pi}{sup +}{nu}-bar , and the ratio {tau}(p->K{sup 0}e{sub {alpha}}{sup +})/{tau}(p->{pi}{sup 0}e{sub {alpha}}{sup +})

Highly excited bound-state resonances of short-range inverse power-law potentials

Energy Technology Data Exchange (ETDEWEB)

Hod, Shahar [The Ruppin Academic Center, Emeq Hefer (Israel); The Hadassah Academic College, Jerusalem (Israel)

2017-11-15

We study analytically the radial Schroedinger equation with long-range attractive potentials whose asymptotic behaviors are dominated by inverse power-law tails of the form V(r) = -β{sub n}r{sup -n} with n > 2. In particular, assuming that the effective radial potential is characterized by a short-range infinitely repulsive core of radius R, we derive a compact analytical formula for the threshold energy E{sub l}{sup max} = E{sub l}{sup max}(n, β{sub n}, R), which characterizes the most weakly bound-state resonance (the most excited energy level) of the quantum system. (orig.)

Charge symmetry breaking nuclear forces and the properties of nuclear matter

International Nuclear Information System (INIS)

Haensel, P.

1977-01-01

The charge symmetry breaking (CSB) component of the nuclear forces yields the charge asymmetric term Esub(a)(N-Z)/A in the nuclear binding energy of nuclear matter. Calculation performed with several models of the CSB nuclear forces, and accounting for the strong short-range two-body correlations, gives Esub(a) approximately -0.2 MeV at the normal nuclear density. The charge asymmetry of the effective nucleon-nucleon interaction is determined primarily by the CSB nuclear forces at the neutron excess, observed in finite nuclei. The exclusion principle and dispersion (self-consistency) effects of the nuclear medium decrease this charge asymmetry. (author)

Measurement of the cross section for the process ν/sub μ/ + e- → ν/sub μ/ + e- at high energies

International Nuclear Information System (INIS)

Baltay, C.; Caroumbalis, D.; French, H.

1978-01-01

There were 11 events of the reaction ν/sub μ/ + e - → ν/sub μ/ + e - observed in a sample of 106,000 charged current neutrino interactions in a heavy neon--hydrogen mixture in the 15 ft. bubble chamber at Fermilab. A cross section was obtained for this process of (1.8 +- 0.8) x 10 -42 E/sub ν/ cm -2 , where E/sub ν/ is the incident neutrino energy in units of GeV. This result is in good agreement with the prediction of the Weinberg--Salam model with sin 2 theta/sub w/ = 0.2. 10 references

Speeds of film-screen combinations for radiography

International Nuclear Information System (INIS)

Holloway, A.F.; Cheng, C.N.; Paix, D.

1983-01-01

Values of Esub(x), the exposure required to yield a net optical density of 1.0, were determined for 12 blue- and nine green-sensitive film types used with 11 blue- and eight green-emitting screen types respectively. The measurements were made using x-rays generated at 80 kVp and 200 mA, under conditions simulating clinical procedures. To examine reciprocity law failure many of the determinations were repeated under similar conditions but at 15 mA. The values of Esub(x) obtained at 15 mA were 6 percent to 93 percent greater than those at 200 mA

Antigens of hepatitis B virus: failure to detect HBeAg on the surfaces of HBsAg forms

Energy Technology Data Exchange (ETDEWEB)

Gerin, J L [Oak Ridge National Lab., Rockville, MD; Shih, J W.K.; McAuliffee, V J; Purcell, R H

1978-01-01

The particulate forms of HBsAg were analysed for the presence of HBeAG on their surfaces. By immunodiffusion analysis, anti-HBe did not form precipitin bands with the purified forms of HBsAg and hyperimmune guinea pig antisera to these forms did not react with HBeAg. Lines of non-identity were observed between the HBeAg determinants (e/sub 1/ and e/sub 2/) and the Dane particles and filaments isolated from an HBeAg-positive serum. Finally, anti-HBe failed to precipitate the polymerase-positive subpopulation of Dane particles, indicating that anti-HBe has no direct role in virus neutralization.

Moessbauer investigation of SnO under hydrostatic pressure up to 41 kbar

International Nuclear Information System (INIS)

Kapitanov, E.V.; Yakovlev, E.N.

1979-01-01

Influence of hydrostatic pressure, P, on the probability of recoilless absorption, f, relative absorption line position, ΔE, and quadrupole splitting, ΔEsub(Q), of Moessbauer spectrum are experimentally determined. Results of a Moessbauer study of SnO point to a linear increase of f, decreases of the electron density at the tin nucleus and increases Esub(Q) with increasing P. The phase transition in SnO discovered earlier in non hydrostatic conditions is not detected. This fact is used to make conclusion that it is necessary to take into account shearing stresses for this phase transition. (author)

Double resonance Raman effects in InN nanowires

Energy Technology Data Exchange (ETDEWEB)

Domenech-Amador, N.; Cusco, R.; Artus, L. [Institut Jaume Almera, Consell Superior d' Investigacions Cientifiques (CSIC), Lluis Sole i Sabaris s.n., Barcelona, Catalonia (Spain); Calarco, R. [Institute of Bio- and Nanosystems, Research Center Juelich GmbH, Juelich (Germany); Paul-Drude-Institut fuer Festkoerperelektronik, Berlin (Germany); Yamaguchi, T.; Nanishi, Y. [Faculty of Science and Engineering, Ritsumeikan University, Noji-Higashi, Kusatsu, Shiga 525-8577 (Japan)

2012-04-15

We study the excitation wavelength dependence of the Raman spectra of InN nanowires. The E{sub 1}(LO) phonon mode, which is detected in backscattering configuration because of light entering through lateral faces, exhibits an upward frequency shift that can be explained by Martin's double resonance. The E{sub 1} (LO)/E{sub 2}{sup h} intensity ratio increases with the excitation wavelength more rapidly than the A{sub 1}(LO)/E{sub 2}{sup h} ratio measured in InN thin films. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Accurate ab initio potential energy surface, thermochemistry, and dynamics of the F{sup −} + CH{sub 3}F S{sub N}2 and proton-abstraction reactions

Energy Technology Data Exchange (ETDEWEB)

Szabó, István; Telekes, Hajnalka; Czakó, Gábor, E-mail: czako@chem.elte.hu [Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, H-1518 Budapest 112, P.O. Box 32 (Hungary)

2015-06-28

We develop a full-dimensional global analytical potential energy surface (PES) for the F{sup −} + CH{sub 3}F reaction by fitting about 50 000 energy points obtained by an explicitly correlated composite method based on the second-order Møller–Plesset perturbation-F12 and coupled-cluster singles, doubles, and perturbative triples-F12a methods and the cc-pVnZ-F12 [n = D, T] basis sets. The PES accurately describes the (a) back-side attack Walden inversion mechanism involving the pre- and post-reaction (b) ion-dipole and (c) hydrogen-bonded complexes, the configuration-retaining (d) front-side attack and (e) double-inversion substitution pathways, as well as (f) the proton-abstraction channel. The benchmark quality relative energies of all the important stationary points are computed using the focal-point analysis (FPA) approach considering electron correlation up to coupled-cluster singles, doubles, triples, and perturbative quadruples method, extrapolation to the complete basis set limit, core-valence correlation, and scalar relativistic effects. The FPA classical(adiabatic) barrier heights of (a), (d), and (e) are −0.45(−0.61), 46.07(45.16), and 29.18(26.07) kcal mol{sup −1}, respectively, the dissociation energies of (b) and (c) are 13.81(13.56) and 13.73(13.52) kcal mol{sup −1}, respectively, and the endothermicity of (f) is 42.54(38.11) kcal mol{sup −1}. Quasiclassical trajectory computations of cross sections, scattering (θ) and initial attack (α) angle distributions, as well as translational and internal energy distributions are performed for the F{sup −} + CH{sub 3}F(v = 0) reaction using the new PES. Apart from low collision energies (E{sub coll}), the S{sub N}2 excitation function is nearly constant, the abstraction cross sections rapidly increase with E{sub coll} from a threshold of ∼40 kcal mol{sup −1}, and retention trajectories via double inversion are found above E{sub coll} = ∼ 30 kcal mol{sup −1}, and at E{sub coll} = �

Giant quadrupole resonance in 12C, 24Mg, and 27Al observed via deuteron inelastic scattering

International Nuclear Information System (INIS)

Chang, C.C.; Didelez, J.P.; Kwiatowski, K.; Wo, J.R.

1977-06-01

Giant quadrupole resonance in 12 C, 24 Mg, and 27 Al was studied using 70 MeV deuteron beam. The results clearly show, in all three targets, resonance-like structures peaked at E/sub x/ approximately 63A/sup -1/3/ MeV, with a width of about 10 MeV. The experimental angular distributions for these resonances agree well with the l = 2 DWBA prediction. For 12 C, a binary splitting was observed, and for 24 Mg, there are indications of finer structure in the main giant quadrupole resonance region

Influence of the effective mass of water molecule on thermal neutron scattering; Uticaj efektivne mase molekula vode na rasejanje termalnih neutrona

Energy Technology Data Exchange (ETDEWEB)

Markovic, M [Belgrade Univ. (Yugoslavia). Elektrotehnicki Fakultet

1981-07-01

The influence of the effective water molecule mass on the thermal neutron scattering on the nucleus of the hydrogen atom has been investigated. Besides the actual water molecule mass (M = 18) the investigations have been carried out with its two effective values (M1 = 16 and M2 = 20). The differential and total cross sections have been calculated for the incident thermal neutron energy E{sub o} = 1 eV. Investigation results show different prominence of the quantum effects and for M2 the appearance of peaks in the quasielastic scattering. (author)

The influence of the deviation from the equilibrium deuteron distribution on the neutron spectra in linear pinch geometries

International Nuclear Information System (INIS)

Deutsch, R.; Herold, H.; Kaeppeler, H.J.; Schmidt, H.

1982-07-01

In order to analyse the influence of the deviation from the equilibrium distribution of the fast deuterons on the neutron spectrum, the limiting case, corresponding to a two-dimensional mono-energetic deuteron distribution, was studied. An essential difference in comparison to the equilibrium case is the appearance of a pronounced peak in the side-on spectra at Esub(n)approx.=2.5 MeV. A comparison of the theoretical and experimental data was made. If we take into account the relaxation processes, there results a good agreement between theory and experiment. (orig.)

IsoMS: automated processing of LC-MS data generated by a chemical isotope labeling metabolomics platform.

Science.gov (United States)

Zhou, Ruokun; Tseng, Chiao-Li; Huan, Tao; Li, Liang

2014-05-20

A chemical isotope labeling or isotope coded derivatization (ICD) metabolomics platform uses a chemical derivatization method to introduce a mass tag to all of the metabolites having a common functional group (e.g., amine), followed by LC-MS analysis of the labeled metabolites. To apply this platform to metabolomics studies involving quantitative analysis of different groups of samples, automated data processing is required. Herein, we report a data processing method based on the use of a mass spectral feature unique to the chemical labeling approach, i.e., any differential-isotope-labeled metabolites are detected as peak pairs with a fixed mass difference in a mass spectrum. A software tool, IsoMS, has been developed to process the raw data generated from one or multiple LC-MS runs by peak picking, peak pairing, peak-pair filtering, and peak-pair intensity ratio calculation. The same peak pairs detected from multiple samples are then aligned to produce a CSV file that contains the metabolite information and peak ratios relative to a control (e.g., a pooled sample). This file can be readily exported for further data and statistical analysis, which is illustrated in an example of comparing the metabolomes of human urine samples collected before and after drinking coffee. To demonstrate that this method is reliable for data processing, five (13)C2-/(12)C2-dansyl labeled metabolite standards were analyzed by LC-MS. IsoMS was able to detect these metabolites correctly. In addition, in the analysis of a (13)C2-/(12)C2-dansyl labeled human urine, IsoMS detected 2044 peak pairs, and manual inspection of these peak pairs found 90 false peak pairs, representing a false positive rate of 4.4%. IsoMS for Windows running R is freely available for noncommercial use from www.mycompoundid.org/IsoMS.

THE 2012 FLARE OF PG 1553+113 SEEN WITH H.E.S.S. AND FERMI-LAT

Energy Technology Data Exchange (ETDEWEB)

Abramowski, A. [Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, D-22761 Hamburg (Germany); Aharonian, F.; Benkhali, F. Ait [Max-Planck-Institut für Kernphysik, P.O. Box 103980, D-69029 Heidelberg (Germany); Akhperjanian, A. G. [National Academy of Sciences of the Republic of Armenia, Marshall Baghramian Avenue, 24, 0019 Yerevan, Republic of Armenia (Armenia); Angüner, E. O. [Institut für Physik, Humboldt-Universität zu Berlin, Newtonstr. 15, D-12489 Berlin (Germany); Backes, M. [University of Namibia, Department of Physics, Private Bag 13301, Windhoek (Namibia); Balenderan, S. [University of Durham, Department of Physics, South Road, Durham DH1 3LE (United Kingdom); Balzer, A. [GRAPPA, Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Barnacka, A. [Obserwatorium Astronomiczne, Uniwersytet Jagielloński, ul. Orla 171, 30-244 Kraków (Poland); Becherini, Y. [Department of Physics and Electrical Engineering, Linnaeus University, SE-351 95 Växjö (Sweden); Tjus, J. Becker [Institut für Theoretische Physik, Lehrstuhl IV: Weltraum und Astrophysik, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Berge, D. [GRAPPA, Anton Pannekoek Institute for Astronomy and Institute of High-Energy Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands); Bernhard, S. [Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität Innsbruck, A-6020 Innsbruck (Austria); Collaboration: Collaboration; and others

2015-03-20

Very high energy (VHE, E > 100 GeV) γ-ray flaring activity of the high-frequency peaked BL Lac object PG 1553+113 has been detected by the H.E.S.S. telescopes. The flux of the source increased by a factor of 3 during the nights of 2012 April 26 and 27 with respect to the archival measurements with a hint of intra-night variability. No counterpart of this event has been detected in the Fermi-Large Area Telescope data. This pattern is consistent with VHE γ-ray flaring being caused by the injection of ultrarelativistic particles, emitting γ-rays at the highest energies. The dataset offers a unique opportunity to constrain the redshift of this source at z = 0.49 ± 0.04 using a novel method based on Bayesian statistics. The indication of intra-night variability is used to introduce a novel method to probe for a possible Lorentz invariance violation (LIV), and to set limits on the energy scale at which Quantum Gravity (QG) effects causing LIV may arise. For the subluminal case, the derived limits are E{sub QG,1} > 4.10 × 10{sup 17} GeV and E{sub QG,2} > 2.10 × 10{sup 10} GeV for linear and quadratic LIV effects, respectively.

Electronic structure of the amorphous-crystalline Silicon heterostructure contact; Die elektronische Struktur des amorph-kristallinen Silizium-Heterostruktur-Kontakts

Energy Technology Data Exchange (ETDEWEB)

Korte, L.

2006-07-01

In the present work, the electronic density of states of hydrogenated amorphous silicon (a-Si:H) layers in the thickness range from 300 down to {proportional_to}2 nm was examined by Near-UV-photoelectron spectroscopy (NUV-PES). The measurements yield a mean density (averaged over all directions in k space) of the extended states in the valence band close to the band edge E{sub v}, down to approximately E{sub v}-1 eV, as well as the density of states in the band-gap between E{sub v} and the Fermi level E{sub f}. An analytic model for the density of states was fitted to the measured yield data. The model describes the extended states close to the band edge as well as the localized states in the band gap. The defect parameters obtained from the fits to the 300 nm sample are elevated with respect to literature data. In contrast to PES the photocurrent measurement yield the defect parameters averaged over the entire layer thickness. Finally, the photocurrent measurements can be evaluated in the Tauc plot to yield the optical band-gap, E{sub g}{sup opt}=1.76(5) eV. The methodology developed in the first part of the thesis (PES measurement and fit of the model density of states) was then applied to various series of approximately 10 nm thin a-Si:H layers on c-Si substrates, where the deposition temperature of the layers and the concentration of their doping both by phosphorus and boron were varied. The experimental results can be summarized as follows: Ultrathin a-Si:H layers show an optimum of the deposition-temperature around 230 C. The optimum is characterized by an Urbach energy of 66(1) meV and a defect-density of 2,9(3).10{sup 18} cm{sup -3}. For undoped layers, the Fermi level lies E{sub F}-E{sub V}{sup {mu}}=1.04(6) eV, the films are therefore slightly n-type. Conductivity measurements at identically prepared thick layers on glass allow to determine the distance of the Fermi level to the conduction band mobility edge, E{sub C}{sup {mu}}-E{sub F}. Both for the

MO-C-17A-08: Evaluation of Lung Deformation Using Three Dimensional Strain Maps

Energy Technology Data Exchange (ETDEWEB)

Cui, T [Duke University, Durham, NC (United States); Huang, Q [Duke Unversity, Durham, NC (United States); Miller, W [University of Virginia, Charlottesville, VA (United States); Zhong, X [Siemens Healthcare, Atlanta, GA (United States); Yin, F; Cai, J [Duke University Medical Center, Durham, NC (United States)

2014-06-15

Purpose: To develop a systematic approach to generate three dimensional (3D) strain maps of lung using the displacement vector field (DVF) during the respiratory deformation, and to demonstrate its application in evaluating deformable image registration (DIR). Methods: A DVF based strain tensor at each voxel of interest (VOI) was calculated from the relative displacements between the VOI and each of the six nearest neighbors. The maximum and minimum stretches of a VOI can be determined by the principal strains (E{sub 1}, E{sub 2} and E{sub 3}), which are the eigenvalues and the corresponding strain tensors. Two healthy volunteers enrolled in this study under IRB-approved protocol, each was scanned using 3D Hyperpolarized He-3 tagging-MRI and 3D proton-MRI with TrueFISP sequence at the endof- inhalation (EOI) and the end-of-exhalation (EOE) phases. 3D DVFs of tagging- and proton-MRI were obtained by the direct measurements of the tagging grid trajectory and by the DIR method implemented in commercial software. Results: 3D strain maps were successfully generated for all DVFs. The principal strain E1s were calculated as 0.43±0.05 and 0.17±0.25 for tagging-MRI and proton-MRI, respectively. The large values of E{sub 1} indicate the predominant lung motion in the superior-inferior (SI) direction. Given that the DVFs from the tagging images are considered as the ground truth, the discrepancies in the DIR-based strain maps suggest the inaccuracy of the DIR algorithm. In the E{sub 1} maps of tagging-MRI for subject 1, the fissures were distinguishable by the larger values (0.49±0.02) from the adjacent tissues (0.41±0.03) due to the larger relative displacement between the lung lobes. Conclusion: We have successfully developed a methodology to generate DVF-based 3D strain maps of lung. It can potentially enable us to better understand the pulmonary biomechanics and to evaluate and improve the DIR algorithms for the lung deformation. We are currently studying more

Solar flare X-radiation and energetic particles by the observation data from the Venera-13,14 space probes

International Nuclear Information System (INIS)

Belyakov, S.A.; Dajbog, E.I.; D'yachkov, A.P.

1984-01-01

The relationship between bursts of solar hard X-radiation quanta (Esub(x) > 0.055 MeV) and flares of solar cosmic rays (SCR) was considered on the basis of the data from the Venera-13, 14 space probes. The data on solar flares in Hsub(α) and thermal X-radiation range as well as radio-frequency radiation of the 3d type were used for analysis. It was established that the intensity amplitude of flare electrons (Esub(e) > 0.025 and > 0.07 MeV) and protons (Esub(p) > 1.0 MeV) correlates best with the flare importance in the thermal X-radiation range (r approximately 0.8+-0.03). The use of flare importance in thermal X-radiation range was independent measure of flare power in which SCR particles were generated enabled to construct heliolongitudinal dependences of the flare electron fluxes and to obtain the idea of the heliolongitudinal flare interval in which the effects of coronal propagation could be ignored. It is shown that the flux of the flare nonrelativistic electrons is related with the total energy release in the burst of hard X-radiation better than with the amplitude of this burst. Distributions of the solar events were studied with respect to the amplitudes of the intensity of electrons of SCR, thermal and hard X-radiation. It is shown that in the most part of the varying amplitude ranqe the distribution functions are approximated according to the power law. It is shown that the distribution function factor depends both on the parameter used for its construction and the type of events being used for analysis

Communication: Rovibrationally selected absolute total cross sections for the reaction H{sub 2}O{sup +}(X{sup 2}B{sub 1}; v{sub 1}{sup +}v{sub 2}{sup +}v{sub 3}{sup +}= 000; N{sup +}{sub Ka+Kc+)}+ D{sub 2}: Observation of the rotational enhancement effect

Energy Technology Data Exchange (ETDEWEB)

Xu Yuntao; Xiong Bo; Chang, Yih Chung; Ng, C. Y. [Department of Chemistry, University of California, Davis, California 95616 (United States)

2012-12-28

By employing the newly established vacuum ultraviolet laser pulsed field ionization-photoion (PFI-PI) double quadrupole-double octopole ion guide apparatus, we have measured the rovibrationally selected absolute total cross sections of the ion-molecule reaction H{sub 2}O{sup +}(X{sup 2}B{sub 1}; v{sub 1}{sup +}v{sub 2}{sup +}v{sub 3}{sup +}= 000; N{sup +}{sub Ka+Kc+)}+ D{sub 2}{yields} H{sub 2}DO{sup +}+ D in the center-of-mass collision energy (E{sub cm}) range of 0.05-10.00 eV. The pulsing scheme used for the generation of PFI-PIs has made possible the preparation of reactant H{sub 2}O{sup +}(X{sup 2}B{sub 1}; v{sub 1}{sup +}v{sub 2}{sup +}v{sub 3}{sup +}= 000) ions in single N{sup +}{sub Ka+Kc+} rotational levels with high kinetic energy resolutions. The absolute total cross sections observed in different N{sup +}{sub Ka+Kc+} levels with rotational energies in the range of 0-200 cm{sup -1} were found to exhibit a significant rotational enhancement on the reactivity for the titled reaction. In contrast, the measured cross sections reveal a decreasing trend with increasing E{sub cm}, indicating that the rotational enhancement observed is not a total energy effect, but a dynamical effect. Furthermore, the rotational enhancement is found to be more pronounced as E{sub cm} is decreased. This experiment provided evidence that the coupling of the core rotational angular momentum with the orbital angular momentum could play a role in chemical reactivity, particularly at low E{sub cm}.

Studies on the effect of solvents on self-assembly of thioctic acid and Mercaptohexanol on gold

Energy Technology Data Exchange (ETDEWEB)

Li Zhiguo; Niu Tianxing [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry of China and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China); Zhang Zhenjiang [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry of China and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China); College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215006 (China); Feng Guiying [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry of China and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China); Bi Shuping, E-mail: bisp@nju.edu.c [School of Chemistry and Chemical Engineering, State Key Laboratory of Coordination Chemistry of China and Key Laboratory of MOE for Life Science, Nanjing University, Nanjing 210093 (China)

2011-04-29

In this article we investigated the effect of solvents (CCl{sub 4}, CH{sub 3}CN, DMF, ethanol, ethanol-H{sub 2}O and H{sub 2}O) on self-assembly of Thioctic acid (TA) and Mercaptohexanol (MCH) on gold by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Electrochemical characteristics of TA and MCH self-assembled monolayers (SAMs) formed in different solvents were evaluated by inspecting the ions permeability (interfacial capacitance C and phase angle {phi}{sub 1Hz}) and electron transfer capability (current density difference {Delta}i and charge transfer resistance R{sub ct}). Experimental results indicated that the ability of solvents availing the ordering of SAMs was: for TA, CCl{sub 4} > ethanol > CH{sub 3}CN > ethanol-H{sub 2}O > DMF; for MCH, H{sub 2}O > ethanol-H{sub 2}O {approx} CCl{sub 4} > ethanol {approx} CH{sub 3}CN > DMF. Through relating the C, {phi}{sub 1Hz}, {Delta}i and R{sub ct} of SAMs (TA and MCH) with parameters of solvent (polarity E{sub T}{sup N}, solubility parameter {delta} and octanol/water partition coefficients logP{sub ow}), it was found that solvents with bigger logP{sub ow} (smaller E{sub T}{sup N} and {delta}) availed the ordering of TA-SAMs but the effect of solvents on MCH self-assembly was complex and MCH-SAMs formed in H{sub 2}O (the biggest E{sub T}{sup N}, {delta} and the smallest logP{sub ow}) and CCl{sub 4} (the smallest E{sub T}{sup N}, {delta} and the biggest logP{sub ow}) were more ordered than in other solvents.

Instability and damping of one-dimensional high-amplitude Langmuir waves

International Nuclear Information System (INIS)

Buchel'nikova, N.S.; Matochkin, E.P.

1981-01-01

Numerical experiments (methods ''of particles in cells'') on investigation of instability and damping of one-dimensional Langmuir waves in the region Esub(0)sup(2)/8πnT>m/M>(ksub(0)rsub(d))sup(2) ksub(0) is wave vector, M- ion mass, m-electron mass, v=√T/M, vsub(ph)=Wsub(0)/ksub(0), Wsub(0)-proper plasma frequency) are performed. Numerical experiments have been conducted in a wide range of initial parameters of the wave: E 0 2 /8πnT approximately 4x10 2 -10 -2 , vsub(ph)/vsub(T) approximately 3-160, M/m=10 2 , in some cases M/m=10 3 . It is shown that the basic processes are modulation instability with a modulation length less than the wave length, wave conversion at density inhomogeneity and electron capture by the wave or its harmonics. Depending on initial wave parameters the predominant role is played by this or that process. In the range of linear waves Esub(0)sup(2)/8πnT ksub(0)rsub(d) - to the collapse. In the range of 4x10sup(-2)/(ksub(0)rsub(d)sup(2)>Esub(0)sup(2)/8πnT>10sup(-3)/(ksub(0)rsub(d))sup(2) all the three processes play a comparable role. In the range of strong damping Esub(0)sup(2)/8πnT>4x10sup(-2)/(h ksub(0)rsub(d))sup(2) the main part is played by the wave electron capture resulting in damping considerably exceeding the Lamdau damping [ru

Response of Ni/4H-SiC Schottky barrier diodes to alpha-particle irradiation at different fluences

Energy Technology Data Exchange (ETDEWEB)

Omotoso, E., E-mail: ezekiel.omotoso@up.ac.za [Department of Physics, University of Pretoria, Private Bag X20, Hatfield 0028 (South Africa); Departments of Physics, Obafemi Awolowo University, Ile-Ife 220005 (Nigeria); Meyer, W.E.; Auret, F.D.; Diale, M.; Ngoepe, P.N.M. [Department of Physics, University of Pretoria, Private Bag X20, Hatfield 0028 (South Africa)

2016-01-01

Irradiation experiments have been carried out on 1.9×10{sup 16} cm{sup −3} nitrogen-doped 4H-SiC at room temperature using 5.4 MeV alpha-particle irradiation over a fluence ranges from 2.6×10{sup 10} to 9.2×10{sup 11} cm{sup −2}. Current–voltage (I–V), capacitance–voltage (C–V) and deep level transient spectroscopy (DLTS) measurements have been carried out to study the change in characteristics of the devices and free carrier removal rate due to alpha-particle irradiation, respectively. As radiation fluence increases, the ideality factors increased from 1.20 to 1.85 but the Schottky barrier height (SBH{sub I–V}) decreased from 1.47 to 1.34 eV. Free carrier concentration, N{sub d} decreased with increasing fluence from 1.7×10{sup 16} to 1.1×10{sup 16} cm{sup −2} at approximately 0.70 μm depth. The reduction in N{sub d} shows that defects were induced during the irradiation and have effect on compensating the free carrier. The free carrier removal rate was estimated to be 6480±70 cm{sup −1}. Alpha-particle irradiation introduced two electron traps (E{sub 0.39} and E{sub 0.62}), with activation energies of 0.39±0.03 eV and 0.62±0.08 eV, respectively. The E{sub 0.39} as attribute related to silicon or carbon vacancy, while the E{sub 0.62} has the attribute of Z{sub 1}/Z{sub 2}.

Experimental investigation and exergy analysis of the performance of a counter flow Ranque-Hilsch vortex tube with regard to nozzle cross-section areas

Energy Technology Data Exchange (ETDEWEB)

Dincer, K.; Avci, A.; Berber, A. [Dept. of Mechanical Eng., Fac. of Eng. and Architecture, Selcuk Univ., Selcuklu, Konya (Turkey); Baskaya, S. [Dept. of Mechanical Eng., Fac. of Eng. and Architecture, Gazi Univ., Maltepe, Ankara (Turkey)

2010-08-15

Exergy analysis and performance of a Ranque-Hilsch Vortex Tube (RHVT) with various nozzle cross-section areas (NCSA = 3 x 3, 4 x 4, 5 x 5 mm{sup 2}) were determined under inlet pressures (P{sub i}) of 260, 300 kPa (absolute) pressurized air. The maximum difference in the temperatures of hot output and cold output streams was obtained for NCSA = 3 x 3 mm{sup 2}. The total inlet exergy (sum E{sub i}), total outlet exergy (sum E{sub O}), total lost exergy (sum E{sub Lost}) and exergy efficiency ({eta}, %) were calculated. It was determined that the exergy efficiency of the system, varied between 1% and 39%, and the highest exergy efficiency was obtained for NCSA = 3 x 3 mm{sup 2}. The exergy efficiency strongly depends on the level of P{sub i}, {xi} and v{sub cold}. Variation of the exergy efficiency decreased with decreasing P{sub i}, {xi}, v{sub cold} and the highest and lowest exergy efficiencies were found when the values of P{sub i}, {xi}, v{sub cold} reached maximum and minimum levels, respectively. (author)

Experiments in high voltage electron microscopy. Progress report, October 31, 1975--August 1976

International Nuclear Information System (INIS)

Mitchell, T.E.; Das, G.; Barnard, R.; Ro, D.

1976-08-01

High voltage electron microscopy (HVEM) is being used to study the effects of irradiation on a variety of materials. The vacancies and interstitials produced by displacement can agglomerate to form dislocation loops and voids, annihilate at sinks, or enhance various diffusion processes such as precipitation and recrystallization. Threshold displacement energies, E/sub d/, have been determined for a number of fcc, bcc, and hcp metals. Directions for minimum E/sub d/ have been correlated with the crystal structure and the magnitude of E/sub d/ has been related to the sublimation energy. The effects of electron irradiation on precipitation in Al--Cu, Al--Si and Ni--Al alloys have been investigated. Precipitation respectively of theta', Si and γ' is enhanced and growth rates are being related quantitatively to theories of radiation-enhanced diffusion. Results on radiation damage in oxides (quartz, alumina, and magnesia) have also been obtained. Displacement damage gives rise to dislocation loop nucleation and growth in all cases, including multi-layer loops in Al 2 O 3 . In SiO 2 , ionization damage also occurs, which destroys the crystallinity. Threshold displacement and temperature effects have also been investigated

Properties of thermal neutron scattering on the nucleus of hydrogen atom of methane molecule; Osobine rasejanja termalnih neutrona na jezgru vodonikovog atoma molekula metana

Energy Technology Data Exchange (ETDEWEB)

Miloradovic, M M [Tehnicki fakultet, Cacak (Yugoslavia); Markovic, M I [Elektrotehnicki fakultet, Beograd (Yugoslavia)

1987-07-01

On the basis of derived quantum-mechanical expression for the microscopic nucleus scattering the single and collective influences of translational, rotational and intravibrational motions of the methane molecule on the thermal neutron scattering are established. When incident neutron energy is E{sub 0} {<=} 0.1 eV, it is found that only translational and rotational motion of the methane molecule influences the thermal neutron scattering. The influence of these motions for E{sub 0} . 0.1 eV decreases rapidly with the increase of the incident neutron energy and then the significant influence on the thermal neutron scattering exerts inelastic scattering on the combined rotational with single intravibrational phonons of the methane molecule, while the inelastic scattering on single intravibrational phonons is significantly less. In the combination with rotational phonons the biggest influence has threefold degenerated deformed intravibrational phonons, somehow less influence has twofold degenerated deformed intravibrational phonons, and the least influence has valent intravibrational phonons. All the effects of quasielastic and quantum inelastic scattering are clearly expressed with the thermal neutron scattering at small angles, so that for E{sub 0} =1 eV practically there is no scattering backward. (author)

Effect of the hydrophilic block length on the surface-active and micellar thermodynamic properties of oxyethylene-oxybutylene diblock copolymers in aqueous solution

International Nuclear Information System (INIS)

Khan, A.; Usman, M.; Siddiq, M.; Fatima, G.; Harrison, W.

2009-01-01

The effect of hydrophilic block length on the surface and micellar thermodynamic properties of aqueous solution of E/sub 40/B/sub 8/, E/sub 80/B/sub 8/ and E/sub 120/B/sub 8/ diblock copolymers, were studied by surface tension measurements over a wide concentration and temperature range; where E stands for an oxyethylene unit and B for an oxybutylene unit. Like conventional surfactants, two breaks (change in the slope) were observed in the surface tension vs logarithm of concentration curve for all the three copolymers. Surface tension measurements were used to estimate surface excess concentrations (r m), area per molecule at air/water interface a and thermodynamic parameters for all adsorption of the pre-micellar region in the temperature range 20 to 50 degree C. Likewise the critical micelle concentration, CMC and thermodynamic parameters for micellization were also calculated for the post-micellar solutions at all temperatures. For comparison the thermodynamic parameters of adsorption and micellization are discussed in detail. The impact of varying E-block length and temperature on all calculated parameters are also discussed. This study shows the importance of hydrophobic-hydrophilic-balance (HHB) of copolymers on various surface and micellar properties. (author)

Gamma-to-electron magnetic spectrometer (GEMS): An energy-resolved {gamma}-ray diagnostic for the National Ignition Facility

Energy Technology Data Exchange (ETDEWEB)

Kim, Y.; Herrmann, H. W.; Mack, J. M.; Young, C. S.; Barlow, D. B.; Schillig, J. B.; Sims, J. R. Jr.; Lopez, F. E.; Mares, D.; Oertel, J. A.; Hayes-Sterbenz, A. C. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Hilsabeck, T. J.; Wu, W. [General Atomics, PO Box 85608, San Diego, California 92186 (United States); Moy, K. [National Security Technologies, Special Technologies Laboratory, Santa Barbara, California 93111 (United States); Stoeffl, W. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2012-10-15

The gamma-to-electron magnetic spectrometer, having better than 5% energy resolution, is proposed to resolve {gamma}-rays in the range of E{sub o}{+-} 20% in single shot, where E{sub o} is the central energy and is tunable from 2 to 25 MeV. Gamma-rays from inertial confinement fusion implosions interact with a thin Compton converter (e.g., beryllium) located at approximately 300 cm from the target chamber center (TCC). Scattered electrons out of the Compton converter enter an electromagnet placed outside the NIF chamber (approximately 600 cm from TCC) where energy selection takes place. The electromagnet provides tunable E{sub o} over a broad range in a compact manner. Energy resolved electrons are measured by an array of quartz Cherenkov converters coupled to photomultipliers. Given 100 detectable electrons in the energy bins of interest, 3 Multiplication-Sign 10{sup 14} minimum deuterium/tritium (DT) neutrons will be required to measure the 4.44 MeV {sup 12}C {gamma}-rays assuming 200 mg/cm{sup 2} plastic ablator areal density and 3 Multiplication-Sign 10{sup 15} minimum DT neutrons to measure the 16.75 MeV DT {gamma}-ray line.

Speed controller for an alternating - current motor

International Nuclear Information System (INIS)

Bolie, V.W.

1984-01-01

A controller for a multi-phase ac motor that is subject to a large inertial load, e.g. an induction motor driving a heavy spinning rotor of a neutron chopper that must be rotated in phase-locked synchronism with a reference pulse train that is representative of an ac power supply signal Esub(L) having a meandering line frequency, includes a sensor which provides a feedback pulse train representative of the actual speed of the motor which is compared (by counting clock pulses between feedback pulses) with a reference clock signal in a computing unit to provide a motor control signal Esub(c). The motor control signal is a weighted linear sum of a speed error signal, a phase error signal, and a drift error signal, the magnitudes of which are recalculated and updated with each revolution of the motor shaft. The speed error signal is constant for large speed errors but highly sensitive to small speed errors. The stator windings of the motor are driven by variable-frequency power amplifiers which are controlled by the motor control signal Esub(c) via PROMs which store digital representations of sine and cosine waveforms in quadrature. (author)

Measurement of deuteron induced gamma-ray emission differential cross sections on {sup nat}Cl from 1.0 to 2.0 MeV

Energy Technology Data Exchange (ETDEWEB)

Jokar, A., E-mail: arezajokar@gmail.com; Kakuee, O.; Lamehi-Rachti, M.

2016-06-15

In this research work, measured differential cross sections for gamma-ray emission from the nuclear reactions {sup 35}Cl(d,pγ{sub 1-0}){sup 36}Cl (E{sub γ} = 788 keV), {sup 35}Cl(d,pγ{sub 2-0}){sup 36}Cl (Eγ = 1165 keV), {sup 37}Cl(d,pγ{sub 1-0}){sup 38}Cl (E{sub γ} = 671 keV) and {sup 37}Cl(d,pγ{sub 2-0}){sup 38}Cl (E{sub γ} = 755 keV) are presented. For these measurements a thin natural BaCl{sub 2} target evaporated onto a 50 μm-thick Mo foil was used. The gamma-rays and backscattered deuterons were detected simultaneously. An HPGe detector placed at an angle of 90° with respect to the beam direction was employed to collect gamma-rays while an ion implanted Si detector placed at a scattering angle of 165° was used to detect backscattered deuterons. The validity of the obtained differential cross sections was verified through a thick target benchmarking experiment. The overall systematic uncertainty of cross section values was estimated to be ±10%.

Ionic electrodeposition of II-VI and III-V compounds. III. Computer simulation of quasi-rest potentials for M/sub 1/X/sub 1/ compounds analogous to CdTe

International Nuclear Information System (INIS)

Engelken, R.D.

1987-01-01

The quasi-rest potential (QRP) has been proposed as a key quantity in characterizing compound semiconductor (e.g. CdTe) electrodeposition. This article expands the modeling/simulation representative of Cd/sub x/Te in chemical equilibrium to calculate two ''QRP's'': E/sub M/1/sub /, the mixed potential occurring immediately after current interruption and before any relaxation in double layer ion concentration and significant ion exchange/surface stoichiometry change occur, and E/sub M/2/sub /, another mixed potential occurring after the double layer ion concentrations have relaxed to their bulk values but still before any significant surface composition change occurs. Significant predictions include existence of a dramatic negative transition in QRP, with negative-going deposition potential, centered on the potential of perfect stoichiometry (PPS), inequality, in general, between the PPS and E/sub M/1/sub / unless the deposit remains in equilibrium with the electrolyte (no ion exchange at open circuit), negligible sensitivity of QRP-E curves to the activity coefficient parameter implying the importance of the PPS in characterizing compound deposition, and disappearance of the transition structure for sufficiently positive Gibbs free energies

Solar wind ∼0.1-1.5 keV electrons at quiet times

Energy Technology Data Exchange (ETDEWEB)

Tao, Jiawei; Wang, Linghua, E-mail: wanglhwang@gmail.com; Zong, Qiugang; He, Jiansen; Tu, Chuanyi [School of Earth and Space Science, Peking University, Beijing 100871 (China); Li, Gang [Department of Physics and CSPAR, University of Alabama in Huntsville, Alabama 35899 (United States); Salem, Chadi S.; Bale, Stuart D. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Wimmer-Schweingruber, Robert F. [Institute for Experimental and Applied Physics, University of Kiel (Germany)

2016-03-25

We present a statistical survey of the energy spectrum of solar wind suprathermal (∼0.1-1.5 keV) electrons measured by the WIND 3-D Plasma & Energetic Particle (3DP) instrument at 1 AU during quiet times at the minimum and maximum of solar cycles 23 and 24. Firstly, we separate strahl (beaming) electrons and halo (isotropic) electrons based on their features in pitch angle distributions. Secondly, we fit the observed energy spectrum of both the strahl and halo electrons at ∼0.1-1.5 keV to a Kappa distribution function with an index κ, effective temperature T{sub eff} and density n{sub 0}. We also integrate the the measurements over ∼0.1-1.5 keV to obtain the average electron energy E{sub avg} of the strahl and halo. We find a strong positive correlation between κ and T{sub eff} for both the strahl and halo, possibly reflecting the nature of the generation of these suprathermal electrons. Among the 245 selected samples, ∼68% have the halo κ smaller than the strahl κ, while ∼50% have the halo E{sub h} larger than the strahl E{sub s}.

On the generation of Alfven wave current drive in low aspect ratio Tokamaks with neoclassical conductivity

Energy Technology Data Exchange (ETDEWEB)

Bruma, C.; Cuperman, S.; Komoshvili, K. [School of Physics and Astronomy, Tel Aviv University, Tel Aviv (Israel)

1998-08-01

Several low aspect ratio (spherical) Tokamaks (ST's) are now in operation or under construction. These devices would permit cost-effective and attractive embodiment of future fusion reactors: they would provide high {beta}, good confinement and steady state operation at modest field values. Now, a steady state reactor has to be sustained by non-inductively driven currents. Recently, the generation of non-inductive current drive by Alfven waves (AWCD) has been investigated theoretically within the framework of ideal (E{sub p}arallel=0) MHD and non-ideal, resistive (E{sub p}arallel{ne}0) MHD; however, in all these cases, the tokamak device consisted of a cylindrical plasma with simulated toroidal effects. Rather encouraging results have been obtained. In this work we further investigate AWCD in ST's as follows: (i) we use consistent equilibrium profiles with neoclassical conductivity corresponding to an ohmic START discharge; (ii) incorporate effects due to neoclassical conductivity in the elements of the resistive MHD dielectric tensor, in the solution of the full (E{sub p}arallel{ne}0) wave equation as well as in the calculation of AWCD; and (iii) carry out a systematic search for antenna parameters optimizing the AWCD. (author)

Ultrawide band gap amorphous oxide semiconductor, Ga–Zn–O

Energy Technology Data Exchange (ETDEWEB)

Kim, Junghwan, E-mail: JH.KIM@lucid.msl.titech.ac.jp [Materials and Structures Laboratory, Tokyo Institute of Technology, Mailbox R3-4, 4259 Nagatsuta, Midori-ku, Yokohama (Japan); Miyokawa, Norihiko; Sekiya, Takumi; Ide, Keisuke [Materials and Structures Laboratory, Tokyo Institute of Technology, Mailbox R3-4, 4259 Nagatsuta, Midori-ku, Yokohama (Japan); Toda, Yoshitake [Materials Research Center for Element Strategy, Tokyo Institute of Technology, Mailbox SE-6, 4259 Nagatsuta, Midori-ku, Yokohama (Japan); Hiramatsu, Hidenori; Hosono, Hideo; Kamiya, Toshio [Materials and Structures Laboratory, Tokyo Institute of Technology, Mailbox R3-4, 4259 Nagatsuta, Midori-ku, Yokohama (Japan); Materials Research Center for Element Strategy, Tokyo Institute of Technology, Mailbox SE-6, 4259 Nagatsuta, Midori-ku, Yokohama (Japan)

2016-09-01

We fabricated amorphous oxide semiconductor films, a-(Ga{sub 1–x}Zn{sub x})O{sub y}, at room temperature on glass, which have widely tunable band gaps (E{sub g}) ranging from 3.47–4.12 eV. The highest electron Hall mobility ~ 7 cm{sup 2} V{sup −1} s{sup −1} was obtained for E{sub g} = ~ 3.8 eV. Ultraviolet photoemission spectroscopy revealed that the increase in E{sub g} with increasing the Ga content comes mostly from the deepening of the valence band maximum level while the conduction band minimum level remains almost unchanged. These characteristics are explained by their electronic structures. As these films can be fabricated at room temperature on plastic, this achievement extends the applications of flexible electronics to opto-electronic integrated circuits associated with deep ultraviolet region. - Highlights: • Incorporation of H/H{sub 2}O stabilizes the amorphous phase. • Ultrawide band gap (~ 3.8 eV) amorphous oxide semiconductor was fabricated. • The increase in band gap comes mostly from the deepening of the valence band maximum level. • Donor level is more likely aligned to the valence band maximum level.

Studies of defects in neutron-irradiated p-type silicon by admittance measurements of n+-p diodes

International Nuclear Information System (INIS)

Tokuda, Y.; Usami, A.

1978-01-01

Defects introduced in p-type silicon by neutron irradiation were studied by measuring the admittance of n + -p diodes. It was shown that the energy levels and capture cross sections estimated from the temperature dependence of the admittance had some uncertainty due to the temperature dependence of the concentration of free carriers in the bulk and the high-frequency-junction capacitance. So, we presented the method of determination of the energy levels, capture cross sections, and concentrations of defects from the frequency dependence of the admittance. This method consists of the measurements of G/ω and C as a function of frequency. From this method, assuming that capture cross sections are independent of temperature, the energy levels of E/sub v/+0.16 and E/sub v/+0.36 eV were obtained. For these defects, the calculated values of the hole capture cross section were 2.4 x 10 -14 and 3.7 x 10 -14 cm 2 , respectively. Comparing with other published data, the energy level of E/sub v/+0.36 eV was found to be correlated with the divacancy

Pulse radiolysis study on several fluoroquinolones

Energy Technology Data Exchange (ETDEWEB)

Zhang Peng [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate University of Chinese Academy of Science, Beijing 100049 (China); Yao Side [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Li Haixia; Song Xiyu; Liu Yancheng [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate University of Chinese Academy of Science, Beijing 100049 (China); Wang Wenfeng, E-mail: wangwenfeng@sinap.ac.c [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

2011-04-15

Reactions of several fluoroquinolones (FQs), including enoxacin, norfloxacin, and ciprofloxacin, with various reactive species such as e{sub aq}{sup -}, N{sup {center_dot}}{sub 3}, and {sup {center_dot}O}H are investigated by pulse radiolysis techniques. The FQ radical anions formed in the reactions of FQs with e{sub aq}{sup -} could either be protonated or deprotonated, and the absorption of FQ radical anions was located around 370 nm. The absorption of the neutral radicals produced in the protonation, and the radical dianions produced in the deprotonation of FQ radical anions were located in the 500-750 nm region. The FQ radical cations formed in the reactions of FQs with N{sub 3}{sup {center_dot}} showed an absorption band around 360 nm. Due to the strong bleaching below 350 nm, the absorption maxima ({lambda}{sub max}) of FQ radical anions, and the {lambda}{sub max} of FQ radical cations were not confirmed. The absorption of the FQ radical anions and cations was clearly pH dependent. Under neutral conditions, the reaction rate constants of FQs with e{sub aq}{sup -} and {sup {center_dot}O}H, which are diffusion controlled, were determined.

A pulse-radiolysis study of the manganese-containing superoxide dismutase from Bacillus stearothermophilus

International Nuclear Information System (INIS)

McAdam, M.E.; Fox, R.A.; Lavelle, F.; Fielden, E.M.

1977-01-01

The enzymic reaction mechanism of a manganese-containing superoxide dismutase from Bacillus stearothermophilus was studied by using pulse radiolysis. During catalysis (pH 8.9; 25 0 C), changes occurring in the kinetics of substrate disappearance and in the visible absorption of the enzyme at 480 nm established that the simple two-step mechanism found for copper- and iron-containing superoxide dismutases was not involved. At a low ratio ( 2 sup(-.) was close to exponential, whereas at much higher ratios (> 100) the observed decay was predominantly zero-order. The simplest interpretation of the results invokes a rapid one-electron oxidation-reduction cycle ('the fast cycle') and, concurrently, a slower reaction giving a form of the enzyme that is essentially unreactive towards O 2 sup(-.) but which undergoes a first-order decay to yield fully active native enzyme ('the slow cycle'). The fast cycle involved the native enzyme Esub(A) and a form of the enzyme Esub(B) which could be obtained also be treating the form Esub(A) with H 2 O 2 . Computer calculations made with such a simple model predicted behaviour in excellent agreement with the observed results. (author)

A Family of Salmonella Virulence Factors Functions as a Distinct Class of Autoregulated E3 Ubiquitin Ligases

Energy Technology Data Exchange (ETDEWEB)

Quezada, C.; Hicks, S; Galan, J; Stebbins, C

2009-01-01

Processes as diverse as receptor binding and signaling, cytoskeletal dynamics, and programmed cell death are manipulated by mimics of host proteins encoded by pathogenic bacteria. We show here that the Salmonella virulence factor SspH2 belongs to a growing class of bacterial effector proteins that harness and subvert the eukaryotic ubiquitination pathway. This virulence protein possesses ubiquitination activity that depends on a conserved cysteine residue. A crystal structure of SspH2 reveals a canonical leucine-rich repeat (LRR) domain that interacts with a unique E{sub 3} ligase [which we have termed NEL for Novel E{sub 3} Ligase] C-terminal fold unrelated to previously observed HECT or RING-finger E{sub 3} ligases. Moreover, the LRR domain sequesters the catalytic cysteine residue contained in the NEL domain, and we suggest a mechanism for activation of the ligase requiring a substantial conformational change to release the catalytic domain for function. We also show that the N-terminal domain targets SspH2 to the apical plasma membrane of polarized epithelial cells and propose a model whereby binding of the LRR to proteins at the target site releases the ligase domain for site-specific function.

Resonance strengths in the {sup 17,18}O(p, α){sup 14,15}N reactions and background suppression underground. Commissioning of a new setup for charged-particle detection at LUNA

Energy Technology Data Exchange (ETDEWEB)

Bruno, C.G.; Scott, D.A.; Aliotta, M.; Davinson, T.; Griffin, C.J. [University of Edinburgh, SUPA, School of Physics and Astronomy, Edinburgh (United Kingdom); Formicola, A.; Best, A.; Junker, M. [Laboratori Nazionali del Gran Sasso, INFN, Assergi (Italy); Anders, M.; Bemmerer, D.; Szuecs, T. [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Broggini, C.; Menegazzo, R. [INFN, Padova (Italy); Caciolli, A.; Depalo, R. [INFN, Padova (Italy); Universita di Padova, Dipartimento di Fisica e Astronomia, Padova (Italy); Cavanna, F.; Corvisiero, P.; Prati, P. [INFN, Genova (Italy); Dipartimento di Fisica, Universita di Genova, Genova (Italy); Di Leva, A.; Imbriani, G. [Universita di Napoli ' ' Federico II' ' , Dipartimento di Scienze Fisiche, Napoli (Italy); Elekes, Z.; Fueloep, Zs.; Gyuerky, Gy.; Somorjai, E. [MTA Atomki, Institute of Nuclear Research, Debrecen (Hungary); Gervino, G. [Universita degli Studi di Torino, Dipartimento di Fisica Sperimentale, Torino (Italy); Guglielmetti, A.; Trezzi, D. [Universita degli Studi di Milano (Italy); INFN, Milano (Italy); Gustavino, C. [INFN, Roma (Italy); Napolitani, E. [Universita di Padova, Dipartimento di Fisica e Astronomia, Padova (Italy); Straniero, O. [Laboratori Nazionali del Gran Sasso, INFN, Assergi (Italy); Osservatorio Astronomico di Collurania, Teramo (Italy); Strieder, F. [South Dakota School of Mines and Technology, Rapid City, SD (United States); Collaboration: LUNA Collaboration

2015-08-15

We report on measurements of resonance strengths and energies for the E{sub p} = 151 and 193 keV resonances in the {sup 18}O(p, α){sup 15}N and {sup 17}O(p, α){sup 14}N reactions, respectively, obtained during commissioning of a new setup for alpha-particle detection studies at the LUNA underground laboratory. Our values, ωγ(151) = 164.2 ± 0.9{sub stat-11.7}{sup +12.1}{sub syst} meV and ωγ (193) = 1.68 ± 0.03{sub stat} ± 0.12{sub syst} meV, are in excellent agreement with those reported in the literature. New values of resonance energies are E{sub p} = 151.2 ± 0.3 keV and E{sub p} = 194.8 ± 0.3 keV, respectively, this latter with the highest precision to date. Comparative background measurements in silicon detectors overground and underground were also carried out, yielding up to a factor of 15 in background suppression at LUNA at energies around 200 keV. This clearly demonstrates the usefulness of underground measurements in charged-particles experiments, especially at low detection energies. (orig.)

Time-resolved spectroscopy of CsI(CO{sub 3}) scintillator

Energy Technology Data Exchange (ETDEWEB)

Yakovlev, V. [National Research Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk 634034 (Russian Federation); Trefilova, L., E-mail: laratrefilova@ukr.net [National University of Civil Protection, 94 Chernyshevska Street, Kharkiv 61023 (Ukraine); Lebedinsky, A.; Daulet, Z. [National Research Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk 634034 (Russian Federation); Dubtsov, I. [Institute for Scintillation Materials, NAS of Ukraine, 60 Lenin Avenue, Kharkiv 61001 (Ukraine)

2016-05-15

The spectral-kinetics characteristics of short-living absorption and luminescence induced by an electron pulse irradiation (E{sub e}=0.25 MeV, t{sub 1/2}= 7ns, W=2×10{sup 10}÷4×10{sup 12} electron/cm{sup 2}) in CsI(CO{sub 3}) crystal are studied. It is shown that the scintillation pulse of CsI(CO{sub 3}) crystal is caused by the radiative annihilation of perturbed two-halogen excitons of two types, which are located in nearby impurity-vacancy dipole [CO{sub 3}{sup 2–}−υ{sub a}{sup +}] anion sites. The processes responsible for post-radiation rise and decay of both CO{sub 3}{sup 2–}-related luminescence bands with maxima at 2.8 and 3.2 eV are monomolecular with the thermal activation energy E{sub rise}=0.1 eV and E{sub decay}=0.05 eV. The cathodoluminescence pulse kinetics is discussed in the terms of the thermally assistant release of holes captured by CO{sub 3}{sup 2–}-ions and the formation of CO{sub 3}{sup 2–}-perturbed two-halide excitons.

Method of evaluation of structural (screen) and quantum graininess of X-ray pictures

Energy Technology Data Exchange (ETDEWEB)

Gurvich, A M; Shamanov, A A; Erofeeva, N D [Nauchno-Issledovatel' skij Inst. Rentgenologii i Radiologii, Moscow (USSR)

1979-03-01

Proposed is a method for quantitative determination of graininess of X-ray pictures (gamma-ray images), the graininess being conditioned by the structure of amplifying screens and quantum fluctuations. The method is based on the determination of threshold brightness at which the picture graininess becomes obvious. It is shown that at low effective quantum energy (Esub(eff.) <= 50 keV) the graininess observed is for the most part structural (screen). Its growth is connected with quantum fluctuations when increasing Esub(eff.) up to 150 keV and using screens with high output values of X-ray luminescence and the coefficient of spectral accordance to the film.

(p,t) reaction on /sup 12/C, /sup 54/Fe and /sup 208/Pb at 80 MeV. [80 MeV, angular distributions, zerio-range DWBA

Energy Technology Data Exchange (ETDEWEB)

Shepard, J R; Anderson, R E; Kraushaar, J J; Ristinen, R A [Colorado Univ., Boulder (USA). Nuclear Physics Lab.; Comfort, J R [Pittsburgh Univ., PA (USA). Dept. of Physics; King, N S.P. [Los Alamos Scientific Lab., NM (USA); Bacher, A; Jacobs, W W [Indiana Univ., Bloomington (USA). Dept. of Physics

1979-06-11

Angular distributions have been measured for the low-lying levels of the residual nuclei for the /sup 12/C, /sup 54/Fe and /sup 208/Pb(p,t) reactions at E/sub p/ = 80 MeV. The shapes of these angular distributions are generally well reproduced by the zero-range distorted-wave Born approximation (DWBA). Enhancement factors extracted from the data show that the DWBA predicts relative strengths consistent with those observed at lower bombarding energies. However, the overall empirical DWBA normalization at E/sub p/ = 80 MeV is observed to be 1/12(1/4) of that required at 40 MeV for /sup 208/Pb(/sup 54/Fe).

Time evolution of the vacuum - pair production in high intensity laser fields

Energy Technology Data Exchange (ETDEWEB)

Woellert, Anton; Bauke, Heiko; Keitel, Christoph H. [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

2013-07-01

Interaction between the vacuum and high intensity lasers will lead to new possibilities in high-field physics. We present numerical ab initio studies for time evolution of the vacuum state into multiple pair states. The high intensity laser field of two counter-propagating beams is treated classically and in the non-perturbative regime (E{sub 0}/ω ∝ 1). In this regime, the time needed by an electron to become relativistic in presence of a static field E{sub 0} is of same order as the period of the laser field. Pair state probabilities as well as correlations are investigated in real-time depending on polarization and field strength.

Nuclear effects on elastic reactions induced by neutrinos and antineutrinos

International Nuclear Information System (INIS)

Schaeffer, M.; Bonneaud, G.

1977-01-01

Two nuclear effects are studied on the reactions νn→μ - p and mean number of neutrons νp→μ + n: inhibition effect (due to Pauli principle) and kinematical effects due to the Fermi motion of the target nucleon inside a nucleus. By comparison with shell-model calculations it is shown that the Fermi-gas model is sufficiently accurate to describe the low-Q 2 inhibition effects. The incertitude on Esub(mean number of neutrons) and Q 2 , due to Fermi motion, is studied with a set of curves which give the error on Esub(mean number of neutrons) and Q 2 once Psub(μ) is given [fr

Alpha-heavy-ion angular correlations from /sup 28/Si + /sup 12/C. [84 to 91. 5 MeV

Energy Technology Data Exchange (ETDEWEB)

Ost, R; Cole, A J [Institut des Sciences Nucleaires, 38 - Grenoble (France); Clover, M R; Fulton, B R; Sikora, B [Rochester Univ., NY (USA). Nuclear Structure Research Lab.

1980-06-01

Alpha particles have been measured in coincidence with heavy recoil nuclei from the /sup 28/Si + /sup 12/C reaction. At Esub(lab) = 87 MeV angular correlations for alphas between 15/sup 0/ and 55/sup 0/ and heavy ions at angles -9/sup 0/, -12/sup 0/ and -15/sup 0/ have been taken. An excitation function of coincidence events with THETAsub(..cap alpha..) = 30/sup 0/ and THETAsub(HI) = -12/sup 0/ has been measured for 84 MeV < Esub(lab) < 91.5 MeV. The results are well described by a statistical-model calculation for compound nucleus decay. No evidence is found for additional processes.

Immobilization of radioactive waste in cement-based matrices

International Nuclear Information System (INIS)

Glasser, F.P.; Rahman, A.A.; Macphee, D.; Angus, M.J.; Atkins, M.; Dept. of Chemistry)

1985-01-01

A solubility model of the system CaO-SiO 2 -H 2 O is developed which takes account of the state of Si polymerization in the solid. Free energies of formations of its bonding hydrogel are tabulated. The internal redox conditions in cements have been measured; in particular, slags lower the Esub(eta) relative to OPC. The fate of Sr and U in cement systems has been determined; Sr is incorporated in the aluminate phases, while U 6+ is precipitated as Ca-U-O-H 2 O phases. Lowering the internal Esub(eta) reduces U solubility. Studies of the carbonation of slag-cement blends are reported. (author)

Tunable redox potential of nonmetal doped monolayer MoS{sub 2}: First principle calculations

Energy Technology Data Exchange (ETDEWEB)

Lu, S. [Center for Coordination Bond Engineering, China Jiliang University (China); Li, C., E-mail: canli1983@gmail.com [Center for Coordination Bond Engineering, China Jiliang University (China); School of Materials Science and Engineering, China Jiliang University (China); Zhao, Y.F.; Gong, Y.Y.; Niu, L.Y.; Liu, X.J. [Center for Coordination Bond Engineering, China Jiliang University (China)

2016-10-30

Graphical abstract: Both E{sub CBM} and E{sub VBM} values are affected by the chemical valences of dopants, which also affect the redox potentials of specimens. Compared to the pristine monolayer MoS{sub 2}, the nonmetal ions with odd chemical valences [monovalent (H{sup +}, F{sup –}, Cl{sup –}, Br{sup –} and I{sup –}), trivalent (N{sup 3–}, P{sup 3–} and As{sup 3–}) and pentavalence (B{sup 5–})] enhance the oxidation potential and reduce the reduction potential of specimens, but the nonmetal ions with even chemical valences [divalent (O{sup 2–}, Se{sup 2–} and Te{sup 2–}) and quadravalent (C{sup 4–} and Si{sup 4–})] have the opposite effects on the redox potentials. Display Omitted - Highlights: • The newly formed chemical bonds affect the electronic distribution around the dopants and the nearby Mo atoms. • Compared to pristine monolayer MoS{sub 2}, the nonmetal ions with odd (even) chemical valences enhance (reduce) the oxidation potential and reduce (enhance) the reduction potential of specimens. • The lone pair electrons in nonmetal ions with odd chemical valences extra interact with the Mo ions which reduces the E{sub CBM} and E{sub VBM} values of specimens. - Abstract: Doping is an effective method to alter the electronic behavior of materials by forming new chemical bonds and bringing bond relaxation. With this aid of first principle calculations, the crystal configuration and electronic properties of monolayer MoS{sub 2} have been modulated by the nonmetal (NM) dopants (H, B, C, N, O, F, Si, P, Cl, As, Se, Br, Te and I), and the thermodynamic stability depending on the preparation conditions (Mo-rich and S-rich conditions) were discussed. Results shown that, the NM dopants substituted preferentially for S under Mo-rich condition, the electronic distribution around the dopants and the nearby Mo atoms are changed by the new formed Mo-NM bonds and bands relaxation. Compared to pristine monolayer MoS{sub 2}, the NM ions with odd

SWIFT GRB GRB071010B: OUTLIER OF THE E srcpeak - E γ AND E iso - E srcpeak - t srcjet CORRELATIONS

International Nuclear Information System (INIS)

Urata, Yuji; Lee, Induk; Ip, Wing Huen; Huang, Kuiyun; Im, Myungshin; Deng Jinsong; Liping Xin; Qiu Yulei; Wei Jianyan; Zheng Weikang; Krimm, Hans; Ohno, Masanori; Sugita, Satoshi; Tashiro, Makoto; Yamaoka, Kazutaka

2009-01-01

We present multi-band results for GRB071010B based on Swift, Suzaku, and ground-based optical observations. This burst is an ideal target to evaluate the robustness of the E src peak - E iso and E src peak - E γ relations, whose studies have been in stagnation due to the lack of the combined estimation of E src peak and long-term optical monitoring. The joint prompt spectral fitting using Swift/Burst Alert Telescope and Suzaku/Wide-band All-sky Monitor data yielded the spectral peak energy as E src peak of 86.5 +6.4 -6.3 keV and E iso of 2.25 +0.19 -0.16 x 10 52 erg with z = 0.947. The optical afterglow light curve is well fitted by a simple power law with temporal index α = -0.60 ± 0.02. The lower limit of temporal break in the optical light curve is 9.8 days. Our multi-wavelength analysis reveals that GRB071010B follows E src peak - E iso but violates the E src peak - E γ and E iso - E src peak - t src jet at more than the 3σ level.

Surface modifications caused by a swift heavy ion irradiation on crystalline p-type gallium antimonide

Energy Technology Data Exchange (ETDEWEB)

Jadhav, Vidya, E-mail: vj1510@yahoo.com

2015-09-01

Surface modifications caused by a swift heavy ion irradiation on crystalline p-type gallium antimonide crystal have been reported. Single crystal, 1 0 0〉 orientations and ∼500 μm thick p-type GaSb samples with carrier concentration of 3.30 × 10{sup 17} cm{sup −3} were irradiated at 100 MeV Fe{sup 7+} ions. We have used 15UD Pelletron facilities at IUAC with varying fluences of 5 × 10{sup 10}–1 × 10{sup 14} ions cm{sup −2}. The effects of irradiation on these samples have been investigated using, spectroscopic ellipsometry, atomic force microscopy and ultraviolet–visible–NIR spectroscopy techniques. Ellipsometry parameters, psi (Ψ) and delta (Δ) for the unirradiated sample and samples irradiated with different fluences were recorded. The data were fit to a three phase model to determine the refractive index and extinction coefficient. The refractive index and extinction coefficient for various fluences in ultraviolet, visible, and infrared, regimes were evaluated. Atomic force microscopy has been used to study these surface modifications. In order to have more statistical information about the surface, we have plotted the height structure histogram for all the samples. For unirradiated sample, we observed the Gaussian fitting. This result indicates the more ordered height structure symmetry. Whereas for the sample irradiated with the fluence of 1 × 10{sup 13}, 5 × 10{sup 13} and 1 × 10{sup 14} ions cm{sup −2}, we observed the scattered data. The width of the histogram for samples irradiated up to the fluence of 1 × 10{sup 13} ion cm{sup −2} was found to be almost same however it decreased at higher fluence. UV reflectance spectra of the sample irradiated with increasing fluences exhibit three peaks at 292, 500 and 617 nm represent the high energy GaSb; E{sub 1}, E{sub 1} + Δ and E{sub 2} band gaps in all irradiated samples.

A facile inexpensive route for SnS thin film solar cells with SnS{sub 2} buffer

Energy Technology Data Exchange (ETDEWEB)

Gedi, Sreedevi [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Solar Photovoltaic Laboratory, Department of Physics, Sri Venkateswasra University, Tirupati 517 502 (India); Minna Reddy, Vasudeva Reddy, E-mail: drmvasudr9@gmail.com [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Solar Photovoltaic Laboratory, Department of Physics, Sri Venkateswasra University, Tirupati 517 502 (India); Pejjai, Babu [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Solar Photovoltaic Laboratory, Department of Physics, Sri Venkateswasra University, Tirupati 517 502 (India); Jeon, Chan-Wook [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Park, Chinho, E-mail: chpark@ynu.ac.kr [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Ramakrishna Reddy, K.T., E-mail: ktrkreddy@gmail.com [Solar Photovoltaic Laboratory, Department of Physics, Sri Venkateswasra University, Tirupati 517 502 (India)

2016-05-30

Graphical abstract: PYS spectra of SnS/SnS{sub 2} interface and the related band diagram. - Highlights: • A low cost SnS solar cell is developed using chemical bath deposition. • We found E{sub I} & χ of SnS (5.3 eV & 4.0 eV) and SnS{sub 2} (6.9 eV & 4.1 eV) films from PYS. • Band offsets of 0.1 eV (E{sub c}) and 1.6 eV (E{sub v}) are estimated for SnS/SnS{sub 2} junction. • SnS based solar cell showed a conversion efficiency of 0.51%. - Abstract: Environment-friendly SnS based thin film solar cells with SnS{sub 2} as buffer layer were successfully fabricated from a facile inexpensive route, chemical bath deposition (CBD). Layer studies revealed that as-grown SnS and SnS{sub 2} films were polycrystalline; (1 1 1)/(0 0 1) peaks as the preferred orientation; 1.3 eV/2.8 eV as optical band gaps; and showed homogeneous microstructure with densely packed grains respectively. Ionization energy and electron affinity values were found by applying photoemission yield spectroscopy (PYS) to the CBD deposited SnS and SnS{sub 2} films for the first time. These values obtained as 5.3 eV and 4.0 eV for SnS films; 6.9 eV and 4.1 eV for SnS{sub 2} films. The band alignment of SnS/SnS{sub 2} junction showed TYPE-II heterostructure. The estimated conduction and valance band offsets were 0.1 eV and 1.6 eV respectively. The current density–voltage (J–V) measurements of the cell showed open circuit voltage (V{sub oc}) of 0.12 V, short circuit current density (J{sub sc}) of 10.87 mA cm{sup −2}, fill factor (FF) of 39% and conversion efficiency of 0.51%.

DISCOVERY OF THE BROAD-LINED TYPE Ic SN 2013cq ASSOCIATED WITH THE VERY ENERGETIC GRB 130427A

Energy Technology Data Exchange (ETDEWEB)

Xu, D.; Krühler, T.; Hjorth, J.; Malesani, D.; Fynbo, J. P. U.; Watson, D. J.; Geier, S. [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 København Ø (Denmark); De Ugarte Postigo, A.; Thöne, C. C.; Sánchez-Ramírez, R. [Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomía s/n, E-18008 Granada (Spain); Leloudas, G. [The Oskar Klein Centre, Department of Physics, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Cano, Z.; Jakobsson, P. [Centre for Astrophysics and Cosmology, Science Institute, University of Iceland, Dunhagi 5, IS-107 Reykjavik (Iceland); Schulze, S. [Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile); Kaper, L. [Astronomical Institute Anton Pannekoek, University of Amsterdam, Science Park 904, NL-1098 XH Amsterdam (Netherlands); Sollerman, J. [The Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Cabrera-Lavers, A. [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Cao, C. [Department of Space Science and Physics, Shandong University at Weihai, Weihai, Shandong 264209 (China); Covino, S. [INAF/Brera Astronomical Observatory, via Bianchi 46, I-23807 Merate (Italy); Flores, H., E-mail: dong@dark-cosmology.dk [Laboratoire Galaxies Etoiles Physique et Instrumentation, Observatoire de Paris, 5 place Jules Janssen, F-92195 Meudon (France); and others

2013-10-20

Long-duration gamma-ray bursts (GRBs) at z < 1 are found in most cases to be accompanied by bright, broad-lined Type Ic supernovae (SNe Ic-BL). The highest-energy GRBs are mostly located at higher redshifts, where the associated SNe are hard to detect observationally. Here, we present early and late observations of the optical counterpart of the very energetic GRB 130427A. Despite its moderate redshift, z = 0.3399 ± 0.0002, GRB 130427A is at the high end of the GRB energy distribution, with an isotropic-equivalent energy release of E{sub iso} ∼ 9.6 × 10{sup 53} erg, more than an order of magnitude more energetic than other GRBs with spectroscopically confirmed SNe. In our dense photometric monitoring, we detect excess flux in the host-subtracted r-band light curve, consistent with that expected from an emerging SN, ∼0.2 mag fainter than the prototypical SN 1998bw. A spectrum obtained around the time of the SN peak (16.7 days after the GRB) reveals broad undulations typical of SNe Ic-BL, confirming the presence of an SN, designated SN 2013cq. The spectral shape and early peak time are similar to those of the high expansion velocity SN 2010bh associated with GRB 100316D. Our findings demonstrate that high-energy, long-duration GRBs, commonly detected at high redshift, can also be associated with SNe Ic-BL, pointing to a common progenitor mechanism.

Effects of mine acid on the longevity and reproductive rate of the Gastrotricha Lepidodermella squammata (Dujardin)

Energy Technology Data Exchange (ETDEWEB)

Faucon, A.S.; Hummon, W.D.

1976-09-30

Effects of mine acid on longevity and reproductive rate of the parthenogenic gastrotrich Lepidodermella squammata were studied under laboratory culture conditions. Water from unpolluted and polluted streams was used, directly or mixed, to establish a series of test conditions at pH 8.1, 7.1, 6.4, 5.2, 4.6, and 3.3. Eggs, cultured individually under each test condition, were observed at 12 h intervals for hatching, daughter egg laying and death. Data representing 50 animals under each test condition were used in the construction of a series of life tables. From these were calculated maximal life expectancy (e/sub x/), net reproductive rate per individual lifetime (R/sub 0/) and intrinsic rate of natural increase (r/sub max/). Values of e, R/sub 0/ and r/sub max/ were maximal at pH 7.1 and were reduced slightly at the higher pH: e/sub x/ was greatly reduced and R/sub 0/ zero at pH 6.4 and 5.2; and e/sub x/ was zero at pH 4.6 and 3.3. Analysis of variance tests indicate significant differences between e/sub x/ values of L. squammata cultured at pH 8.1 and those cultured at pH 7.1, but no differences between R/sub 0/ or r/sub max/. Associated with the decrease in pH was an increase in total conductivity and a decrease in carbonate alkalinity and hence in carbonate conductivity. It appears that L. squammata is capable of living and reproducing at pH 6.0 to 6.5 under field conditions low in carbonates, providing non-carbonate ions are not abundant, or under field conditions high in non-carbonate ions, providing sufficient carbonates are present.

Results of measurements with a superconducting niobium coil resonator at 106 MHz: the story of a coil

International Nuclear Information System (INIS)

Piosczyk, B.

A number of tests were performed with a newly developed coil. The surface was treated by conventional surface treatment methods. In the first tests, breakdown occurred at field strengths E/sub max/ approximately equal to 11 to 14 MV/m. The reason for the early breakdown was presumed to reside in small sites with increased losses which expand above a critical field strength. Only after a series of treatment steps in which a total of about 160 μ had been removed from the coil surface were maximum surface fields of up to E/sub max/ approximately equal to 29 MV/m and B/sub max/ approximately equal to 1050 Oe (greater than or equal to E/sub TW/ approximately equal to 4.0 MV/m) reached. Subsequently, breakdown is usually caused by electrons. A comparison of anodized and unanodized resonators showed no significant difference for the maximum attainable field strengths or in the characteristics with regard to electron loading and sensitivity to gas contamination. In two long-term tests for up to 800 h, the resonator was operated at high HF-field strengths (E/sub max/ approximately equal to 18 to 24 MV/m). An abrupt increase of e-loading, which was connected with increased resonator losses, was observed at certain time intervals. Subsequent He-conditioning for a few minutes reduced this elevated e-loading. With increasing operating time, an increase of surface losses was observed which were evidently caused by electrons impinging on the surface (radiation damage). The magnitude of the radiation damage appears to be rather uncritical for application. This radiation damage does not heal during heating to room temperature. However, light oxidative polishing suffices to eliminate the radiation damage

Inclusive-jet photoproduction at HERA and determination of {alpha}{sub s}

Energy Technology Data Exchange (ETDEWEB)

Abramowicz, H. [Tel Aviv Univ. (Israel). School of Physics; Max Planck Institute for Physics, Munich (Germany); Abt, I. [Max Planck Institute for Physics, Munich (Germany); Adamczyk, L. [AGH-Univ. of Science and Technology, Krakow (PL). Faculty of Physics and Applied Computer Science] (and others)

2012-03-15

Inclusive-jet cross sections have been measured in the reaction ep{yields}e+jet+X for photon virtuality Q{sup 2}<1 GeV{sup 2} and {gamma}p centre-of-mass energies in the region 142E{sub T}{sup jet}, and pseudorapidity, {eta}{sup jet}, for jets with E{sub T}{sup jet}>17 GeV and -1<{eta}{sup jet}<2.5. In addition, measurements of double-differential inclusive-jet cross sections are presented as functions of E{sub T}{sup jet} in different regions of {eta}{sup jet}. Next-to-leading-order QCD calculations give a good description of the measurements, except for jets with low E{sub T}{sup jet} and high {eta}{sup jet}. The influence of non-perturbative effects not related to hadronisation was studied. Measurements of the ratios of cross sections using different jet algorithms are also presented; the measured ratios are well described by calculations including up to O({alpha}{sub s}{sup 2}) terms. Values of {alpha}{sub s}(MZ) were extracted from the measurements and the energy-scale dependence of the coupling was determined. The value of {alpha}{sub s}(MZ) extracted from the measurements based on the k{sub T} jet algorithm is {alpha}{sub s}(MZ) = 0.1206{sub -0.0022}{sup +0.0023}(exp.){sub -0.0035}{sup +0.0042}(th.); the results from the anti-k{sub T} and SIScone algorithms are compatible with this value and have a similar precision.

High and Low Energy Proton Radiation Damage in p/n InP MOCVD Solar Cells

Science.gov (United States)

Rybicki, George; Weinberg, Irv; Scheiman, Dave; Vargas-Aburto, Carlos; Uribe, Roberto

1995-01-01

InP p(+)/n/n(+) solar cells, fabricated by metal organic chemical vapor deposition, (MOCVD) were irradiated with 0.2 MeV and 10 MeV protons to a fluence of 10(exp 13)/sq cm. The power output degradation, IV behavior, carrier concentration and defect concentration were observed at intermediate points throughout the irradiations. The 0.2 MeV proton-irradiated solar cells suffered much greater and more rapid degradation in power output than those irradiated with 10 MeV protons. The efficiency losses were accompanied by larger increases in the recombination currents in the 0.2 MeV proton-irradiated solar cells. The low energy proton irradiations also had a larger impact on the series resistance of the solar cells. Despite the radiation induced damage, the carrier concentration in the base of the solar cells showed no reduction after 10 MeV or 0.2 MeV proton irradiations and even increased during irradiation with 0.2 MeV protons. In a deep level transient spectroscopy (DLTS) study of the irradiated samples, the minority carrier defects H4 and H5 at E(sub v) + 0.33 and E(sub v) + 0.52 eV and the majority carrier defects E7 and El0 at E(sub c) - 0.39 and E(sub c) - 0.74 eV, were observed. The defect introduction rates for the 0.2 MeV proton irradiations were about 20 times higher than for the 10 MeV proton irradiations. The defect El0, observed here after irradiation, has been shown to act as a donor in irradiated n-type InP and may be responsible for obscuring carrier removal. The results of this study are consistent with the much greater damage produced by low energy protons whose limited range causes them to stop in the active region of the solar cell.

Effects of short-term administration of estradiol on reperfusion arrhythmias in rats of different ages

Energy Technology Data Exchange (ETDEWEB)

Savergnini, S.Q.; Reis, A.M. [Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Santos, R.A.S. [1Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Santos, P.E.B. [Departamento de Farmacologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Ferreira, A.J. [Departamento de Morfologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Almeida, A.P. [Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil)

2012-11-01

Little is known about age-related differences in short-term effects of estradiol on ischemia-reperfusion (I/R) insults. The present study was designed to evaluate the effects of short-term treatment with estradiol on reperfusion arrhythmias in isolated hearts of 6-7-week-old and 12-14-month-old female rats. Wistar rats were sham-operated, ovariectomized and treated with vehicle or ovariectomized and treated with 17β-estradiol (E{sub 2}; 5 µg·100 g{sup −1}·day{sup −1}) for 4 days. Hearts were perfused by the Langendorff technique. Reperfusion arrhythmias, i.e., ventricular tachycardia and/or ventricular fibrillation, were induced by 15 min of left coronary artery ligation and 30 min of reperfusion. The duration and incidence of I/R arrhythmias were significantly higher in young rats compared to middle-aged rats (arrhythmia severity index: 9.4 ± 1.0 vs 3.0 ± 0.3 arbitrary units, respectively, P < 0.05). In addition, middle-aged rats showed lower heart rate, systolic tension and coronary flow. Four-day E{sub 2} treatment caused an increase in uterine weight. Although E{sub 2} administration had no significant effect on the duration of I/R arrhythmias in middle-aged rats, it induced a marked reduction in the rhythm disturbances of young rats accompanied by a decrease in heart rate of isolated hearts. Also, this reduction was associated with an increase in QT interval. No significant changes were observed in the QT interval of middle-aged E{sub 2}-treated rats. These data demonstrate that short-term estradiol treatment protects against I/R arrhythmias in hearts of young female rats. The anti-arrhythmogenic effect of estradiol might be related to a lengthening of the QT interval.

Band-gap and sub-band-gap photoelectrochemical processes at nanocrystalline CdS grown on ZnO by successive ionic layer adsorption and reaction method

Energy Technology Data Exchange (ETDEWEB)

Malashchonak, M.V., E-mail: che.malasche@gmail.com [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Streltsov, E.A., E-mail: streltea@bsu.by [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Mazanik, A.V. [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Kulak, A.I., E-mail: kulak@igic.bas-net.by [Institute of General and Inorganic Chemistry, National Academy of Sciences of Belarus, Surganova str., 9/1, Minsk 220072 (Belarus); Poznyak, S.K. [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Stroyuk, O.L., E-mail: stroyuk@inphyschem-nas.kiev.ua [L.V. Pysarzhevsky Institute of Physical Chemistry of National Academy of Sciences of Ukraine, 31 prosp. Nauky, 03028 Kyiv (Ukraine); Kuchmiy, S.Ya. [L.V. Pysarzhevsky Institute of Physical Chemistry of National Academy of Sciences of Ukraine, 31 prosp. Nauky, 03028 Kyiv (Ukraine); Gaiduk, P.I. [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus)

2015-08-31

Cadmium sulfide nanoparticle (NP) deposition by the successive ionic layer adsorption and reaction (SILAR) method on the surface of mesoporous ZnO micro-platelets with a large specific surface area (110 ± 10 m{sup 2}g{sup −1}) results in the formation of ZnO/CdS heterostructures exhibiting a high incident photon-to-current conversion efficiency (Y) not only within the region of CdS fundamental absorption (Y{sub max} = 90%; 0.1 M Na{sub 2}S + 0.1 M Na{sub 2}SO{sub 3}), but also in the sub-band-gap (SBG) range (Y{sub max} = 25%). The onset potentials of SBG photoelectrochemical processes are more positive than the band-gap (BG) onset potential by up to 100 mV. A maximum incident photon-to-current conversion efficiency value for SBG processes is observed at larger amount of deposited CdS in comparison with the case of BG ones. The Urbach energy (E{sub U}) of CdS NPs determined from the photocurrent spectra reaches a maximal value on an early deposition stage (E{sub U} = 93 mV at SILAR cycle number N = 5), then lowers somewhat (E{sub U} = 73 mV at N = 10) and remains steady in the range of N from 20 to 300 (E{sub U} = 67 ± 1 mV). High efficiency of the photoelectrochemical SBG processes are interpreted in terms of light scattering in the ZnO/CdS heterostructures. - Highlights: • ZnO/CdS films demonstrate high quantum efficiency (25%) for sub-band-gap transitions. • Onset photocurrent potentials for sub-band-gap processes differ than those for band-gap ones. • Sub-band-gap transitions are caused by band-tail states in CdS nanoparticles.

Interaction of different poisons with MgCl{sub 2}/TiCl{sub 4} based Ziegler-Natta catalysts

Energy Technology Data Exchange (ETDEWEB)

Bahri-Laleh, Naeimeh, E-mail: n.bahri@ippi.ac.ir

2016-08-30

Highlights: • The interactions between different classes of poison molecules and TiCl{sub 4}/MgCl{sub 2} type Ziegler-Natta catalyst is considered. • Poisons strongly stabilize MgCl{sub 2} crystal surfaces, mostly Ti active center relative to the unpoisoned solid. • Poison molecules decrease catalyst activity by increasing E{sub TS} in olefin polymerization. • Poison molecules do not have significant effect in stereospecifity of ZN catalysts in propylene polymerization. - Abstract: Adsorption of different poison molecules on activated MgCl{sub 2} is investigated within DFT using a cluster model of the MgCl{sub 2} surface with (MgCl{sub 2}){sub 16} formula containing four 4-coordinated and eight 5-coordinated Mg atoms as (110) and (104) surfaces, respectively. Studied poison molecules are chosen as possible impurities in hydrocarbon solvents and monomer feeds and contain water, hydrogensulfide, carbondioxide, molecular oxygen and methanol. First, adsorption of 1–4 molecules of different poisons to the (104) and (110) lateral cuts of MgCl{sub 2}, as well as their adsorption on [MgCl{sub 2}]/TiCl{sub 2}Et active center and AlEt{sub 3} cocatalyst is considered. Results reveal that poisons strongly stabilize both crystal surfaces, mostly Ti active center relative to the unpoisoned solid. Second, energy barrier (E{sub TS}) for ethylene insertion in the presence of different poisons located on the first and second Mg atom relative to the active Ti is calculated. While poison molecule located on the second Mg does not change E{sub TS}, coordination of it into the first Mg atom increases E{sub TS} by 0.9–1.2 kcal mol{sup −1}. In the last part of this manuscript, the stereoselective behavior of active Ti species, with and without poison molecules and external electron donor, is fully explored.

Possible evidence for shape isomeric γ-decay in μ- atoms of 238U

International Nuclear Information System (INIS)

Fromm, W.D.; Ortlepp, H.-G.; Polikanov, S.M.; Schmidt, U.; Zorin, G.N.; Arlt, R.; Musiol, G.

1977-01-01

A search for the γ-decay of the shape isomer in muonic 238 U excited by radiationless transitions has been performed. Seven delayed transitions in the energy region of 700 to 3200 keV have been observed with a large Ge(Li) detector. Two transitions with Esub(γ)=2215 and 3131 keV have been attributed to the decay of the shape isomeric state into levels in the first well. The isomeric shift of the second minimum Esub(II) approximately 600 keV in the presence of the muon and the decrease of the lifetime of the shape isomer to tau=12+-2 ns give arguments in favour of the connection of shape isomerism with large quadrupole deformations. (Auth.)

Higgs boson production by very high energy neutrinos

International Nuclear Information System (INIS)

Mikaelian, K.O.; Oakes, R.J.

1978-11-01

Higgs bosons may be produced by bremsstrahlung off a virtual W/sup +-/ or a Z 0 exchanged in a charged or neutral current neutrino interaction. The production cross sections are calculated, and it is pointed out that they cannot grow quadratically with E/sub nu/ as had been suggested earlier, and it is argued that at best they can increase like the square of ln s/M 2 /sub W,Z/ at very high energies. Using a simple approximation for the propagator effect, numerical results in the high energy regime 1 TeV less than or equal to E/sub nu/ less than or equal to 1000 TeV appropriate for DUMAND. 9 references

E-string theory on Riemann surfaces

Energy Technology Data Exchange (ETDEWEB)

Kim, Hee-Cheol; Vafa, Cumrun [Jefferson Physical Laboratory, Harvard University, Cambridge, MA (United States); Razamat, Shlomo S. [Physics Department, Technion, Haifa (Israel); Zafrir, Gabi [Kavli IPMU (WPI), UTIAS, the University of Tokyo, Kashiwa, Chiba (Japan)

2018-01-15

We study compactifications of the 6d E-string theory, the theory of a small E{sub 8} instanton, to four dimensions. In particular we identify N = 1 field theories in four dimensions corresponding to compactifications on arbitrary Riemann surfaces with punctures and with arbitrary non-abelian flat connections as well as fluxes for the abelian sub-groups of the E{sub 8} flavor symmetry. This sheds light on emergent symmetries in a number of 4d N = 1 SCFTs (including the 'E7 surprise' theory) as well as leads to new predictions for a large number of 4-dimensional exceptional dualities and symmetries. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

A serach for moderate- and high-energy neturino emission correlated with gamma-ray bursts

Science.gov (United States)

Becker-Szendy, R.; Bratton, C. B.; Breault, J.; Casper, D.; Dye, S. T.; Gajewski, W.; Goldhaber, M.; Haines, T. J.; Halverson, P. G.; Kielczewska, D.

1995-01-01

A temporal correlation analysis between moderate- (60 Mev less than or equal to E(sub nu)greater than or equal to 2500 MeV) and high-energy (E(sub nu) greater than or equal to 2000 MeV) neutrino interactions consist of two types: the moderate-energy interactions that are contained within the volume of IMB-3 and the upward-going muons produced by high-energy nu(sub mu) interactions in the rock around the detector. No evidence is found for moderate- or high-energy neutrino emission from GRBs nor for any neutrino/neutrino correlation. The nonobservation of nu/GRB correlations allows upper limits to be placed on the neutrino flux associated with GRBs.

Is the nutation of the solid inner core responsible for the 24-year libration of the pole

International Nuclear Information System (INIS)

Kakuta, Chuichi; Okamoto, Isao; Sasao, Tetsuo

1975-01-01

BUSSE's (1970) theory of the dynamical coupling between the rigid inner core and mantle of the Earth through the pressure reactions in the fluid outer core is examined. It is confirmed that the rigid inner core has the eigenfrequency, (1-rhosub(t)/rhosub(r))esub(r)Ω 0 , of nutation (Ω 0 : the mean rotation rate of the Earth, esub(r): ellipticity of the rigid inner core, and rhosub(t), rhosub(r): the densities of the fluid outer and rigid inner cores, respectively), but it is concluded to be extremely difficult to interpret the 24-yr libration of the pole suggested by MARKOWITZ (1960, 1968) in terms of the nutation with this frequency. (auth.)

Electrooxidation of 2-propanol compared ethanol on Pd electrode in alkaline medium

Energy Technology Data Exchange (ETDEWEB)

Su, Yuzhi; Xu, Changwei; Liu, Zhaoqing [School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006 (China); Liu, Jianping [Dongguan Entry-exit Inspection and Quarantine Bureau, Dongguan 511700 (China)

2009-10-20

Here, the oxidation activity of 2-propanol compared ethanol on Pd electrode has been studied in alkaline medium. We have used the amount of coulombs (coulometry) and apparent activation energy (E{sub a}) to measure the activity of alcohol electrooxidation. The amount of coulombs during alcohol electrooxidation for 2-propanol is much higher than that of ethanol showing that 2-propanol is more easily electrochemically oxidized than ethanol. The E{sub a} values of 2-propanol are lower than that of ethanol at the potential from -0.45 to -0.375 V which is usually used in direct alcohol fuel cells (DAFCs) indicating that 2-propanol shows better electrooxidation activity than ethanol. (author)

Ion heating due to rotation and collision in magnetized plasma

International Nuclear Information System (INIS)

Anderegg, F.; Stern, R.A.; Skiff, F.; Hammel, B.A.; Tran, M.Q.; Paris, P.J.; Kohler, P.

1986-01-01

The E x B rotation and associated collisional ion heating of noble-gas magnetized plasmas are investigated with high resolution by means of laser-induced fluorescence and electrical probes. Plasma rotation results from a radial potential gradient which can be controlled by biasing of the discharge electrodes. The time and space evolution of the potential, the rotation velocity v/sub t//sub h//sub e//sub t//sub a/, and the ion perpendicular temperature indicate that heating is due to the randomization of v/sub t//sub h//sub e//sub t//sub a/ by ion-neutral collisions, and leads to temperature increases as high as a factor of 50 over initial values

Search for linking transitions in {sup 143}Eu

Energy Technology Data Exchange (ETDEWEB)

Lerma, F.; LaFosse, D.R.; Devlin, M. [Washington Univ., Saint Louis, MO (United States)] [and others

1996-12-31

Six SD bands were populated in {sup 143}Eu and {sup 144}Eu, two of which had not been previously observed. Sum spectra were generated to search for two step links from the yrast SD band in {sup 143}Eu. However, no two step links were found. A single link from the SD band in {sup 143}Eu was found at 3364 keV. The level where it feeds into has not been identified. Alpha-particle energy (E{sub {alpha}}) spectra leading to the SD band and to normal states in {sup 143}Eu were measured and a correlation was found between E{sub {alpha}} and the level spin of the residual nucleus.

Parameters of radiation defects in GaP and GaAssub(1-x)Psub(x) with thermostimulated current measurements

International Nuclear Information System (INIS)

Brajlovskij, E.Yu.; Marchuk, N.D.

1980-01-01

Introduction of point defects in gallium phosphide crystals and GaAssub(1-x)Psub(x) solid solutions under the action of 1 MeV electrons is studied by TSC method on Schottky barriers. The TSC spectra processing using the computer is given. In GaP crystals the dominant electron and hole traps are D-centers (Esub(c)-1.24 eV) and M-centers (Esub(v)+1.43 eV). The received level spectrum explains the compensation of conductivity of n- and p-lGaP under irradiation. It is shown that main defects observed in electron irradiated GaP are most likely phosphorus vacancies (D-center)and gallium vacancies (M-center)

Radiation defects in GaP and solid solution of GaAssub(1-x)Psub(x)

International Nuclear Information System (INIS)

Brailovsky, E.Y.; Grigoryan, N.E.; Marchouk, N.D.; Pambuhchyan, N.H.; Tartachnik, V.P.

1979-01-01

The introduction and annealing behaviour of radiation defects in GaP and GaAssub(1-x)Psub(x) at 1 to 50 MeV electron irradiation was investigated by the Hall effect, thermal stimulated current (TSC) and optical absorption. The recovery of electrical properties of irradiated GaAssub(1-x)Psub(x) was dependent on x. From TSC measurement it has been shown that the predominant radiation defects in GaP are electron traps Esub(c) - (1.2 +- 0.1)eV and hole traps Esub(v) + (1.5 +- 0.15)eV which are the cause of n and p decreasing in GaP crystals. The formation of density state 'tails' during irradiation was investigated. (author)

Threshold states in /sup 26/Al. Pt. 2. Extraction of resonance strengths

Energy Technology Data Exchange (ETDEWEB)

Champagne, A E; Howard, A J; Parker, P D [Yale Univ., New Haven, CT (USA). Wright Nuclear Structure Lab.

1983-06-20

The total width of the Esub(c.m.)=376 keV resonance in the /sup 25/Mg+p system has been measured using the /sup 25/Mg(p,..gamma..)/sup 26/Al reaction and is found to be 460+-70 eV. From this information, a resonance strength ..omega gamma..=5.7x10/sup 16/ eV is obtained for the astrophysically important 37.2 keV resonance in /sup 26/Al through an R-matrix parameterization of the relative energy dependence of the resonance width. In a similar manner, an upper limit ..omega gamma..<=1.0x10/sup -11/ eV is deduced for a possible resonance at Esub(c.m.)=94.0 keV.

Vacancy production in molybdenum by low energy light ion bombardment: computer simulation

International Nuclear Information System (INIS)

Hou, M.; Veen, A. van; Caspers, L.M.; Ypma, M.R.

1983-01-01

A comparison is made of the room temperature vacancy production measured with THDS (thermal helium desorption spectrometry) and the Frenkel pair production calculated in the binary collision approximation with MARLOWE for 0.5 to 3 keV He + ions and 1.5 keV protons injected into a Mo(110) crystal. Using the distributions of Frenkel pair separation distances calculated with MARLOWE for various values of the displacement threshold Esub(d), the experimental data are matched by selecting a cut-off radius Rsub(c) so that for separations larger than Rsub(c) the Frenkel pairs survive recombination. It became apparent that all experimental data could be reasonably described by a pair of parameters Esub(d) = 33 eV and Rsub(c) = 3.7 a 0 (a 0 is the lattice cell edge unit). The value of Esub(d) we found is close to the experimentally determined threshold energy for permanent displacements in Mo. A detailed analysis of the recombination process using the MARLOWE results shows that the found cut-off radius corresponds with an effective recombination radius Rsub(o) = 2.8 a 0 . In the literature lower (theoretical) values of Rsub(o) = 1.4 - 2.1 a 0 are quoted for correlated recombination of single Frenkel pairs in molybdenum. (orig.)

Measurement of radiation-enhanced diffusion of La in single crystal thin film CeO{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Pappas, Harrison K. [Department of Nuclear, Radiological, and Plasma Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Heuser, Brent J., E-mail: bheuser@illinois.ed [Department of Nuclear, Radiological, and Plasma Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Strehle, Melissa M. [Department of Nuclear, Radiological, and Plasma Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

2010-10-15

The diffusion of La, a trivalent cation dopant, actinide surrogate, and high-yield fission product, in CeO{sub 2}, a UO{sub 2} nuclear fuel surrogate, during 1.8 MeV Kr{sup +} ion bombardment over a temperature range from 673 K to 1206 K has been measured with secondary ion mass spectroscopy. The diffusivity under these irradiation conditions has been analyzed with a model based on a combination of sink-limited and recombination-limited kinetics. This analysis yielded a cation vacancy migration energy of E{sub m}{sup v} {approx} 0.4 eV below {approx}800 K, were recombination-limited kinetics dominated the behavior. The thermal diffusivity of La in the same system was measured over a range of 873-1073 K and was characterized by an activation enthalpy of E{sub a}=E{sub f}{sup v}+E{sub m}{sup v{approx}}1.4eV. The measurement of both the migration enthalpy and total activation enthalpy separately allows the vacancy formation enthalpy on the cation sublattice to be determined; E{sub f}{sup v} {approx} 1 eV. The mixing parameter under energetic heavy-ion bombardment at room temperature was measured as well and found to be {approx}4 x 10{sup -5} nm{sup 5}/eV.

Boron doping compensation of hydrogenated amorphous and polymorphous germanium thin films for infrared detection applications

Energy Technology Data Exchange (ETDEWEB)

Moreno, M., E-mail: mmoreno@inaoep.mx [National Institute of Astrophysics, Optics and Electronics, INAOE, P.O. Box 51 and 216, Puebla, Z. P. 72840 Puebla (Mexico); Delgadillo, N. [Universidad Autónoma de Tlaxcala, Av. Universidad No. 1, Z. P. 90006 Tlaxcala (Mexico); Torres, A. [National Institute of Astrophysics, Optics and Electronics, INAOE, P.O. Box 51 and 216, Puebla, Z. P. 72840 Puebla (Mexico); Ambrosio, R. [Technology and Engineering Institute, Ciudad Juarez University UACJ, Av. Del Charro 450N, Z. P. 32310 Chihuahua (Mexico); Rosales, P.; Kosarev, A.; Reyes-Betanzo, C.; Hidalga-Wade, J. de la; Zuniga, C.; Calleja, W. [National Institute of Astrophysics, Optics and Electronics, INAOE, P.O. Box 51 and 216, Puebla, Z. P. 72840 Puebla (Mexico)

2013-12-02

In this work we have studied boron doping of hydrogenated amorphous germanium a-Ge:H and polymorphous germanium (pm-Ge:H) in low regimes, in order to compensate the material from n-type (due to oxygen contamination that commonly occurs during plasma deposition) to intrinsic, and in this manner improve the properties that are important for infrared (IR) detection, as activation energy (E{sub a}) and temperature coefficient of resistance (TCR). Electrical, structural and optical characterization was performed on the films produced. Measurements of the temperature dependence of conductivity, room temperature conductivity (σ{sub RT}), E{sub a} and current–voltage characteristics under IR radiation were performed in the compensated a-Ge:H and pm-Ge:H films. Our results demonstrate that, effectively, the values of E{sub a}, TCR and IR detection are improved on the a-Ge:H/pm-Ge:H films, using boron doping in low regimes, which results of interest for infrared detectors. - Highlights: • We reported boron doping compensation of amorphous and polymorphous germanium. • The films were deposited by plasma enhanced chemical vapor deposition. • The aim is to use the films as thermo-sensing elements in un-cooled microbolometers. • Those films have advantages over boron doped a-Si:H used in commercial detectors.

High resolution inelastic electron scattering on 90Zr at low momentum transfer and strong fragmentation of the magnetic quadrupole strength

International Nuclear Information System (INIS)

Meuer, D.; Frey, R.; Hoffmann, D.H.H.; Richter, A.; Spamer, E.; Titze, O.; Knuepfer, W.

1980-01-01

High-resolution (FWHM approx. 30 keV) inelastic electron scattering on 90 Zr at low momentum transfer (0.20 -1 ) has been used to study magnetic transitions at excitation energies Esub(x) = 8-10 MeV. The experimental data were analyzed in the distorted-wave Born approximation (DWBA) with wave functions calculated in the random phase approximation (RPA). Three Jsup(π) = 1 + states have been identified Esub(x) = 8.233, 9.000 and 9.371 MeV. There is some indication of further very fragmented dipole strength and the upper limit for the total M1 strength in the investigated energy region is ΣB(M1)up 2 sub(K). It is much smaller than any theoretical prediction. Furthermore, a large number of 2 - states has been observed, with the center of gravity located at Esub(x) approx. 9 MeV. These states carry a total strength of ΣB(M2)up = 1000 μ 2 sub(K) x fm 2 . Their strong fragmentation is in qualitative agreement with theoretical calculations, but the deduced strength is much smaller than theoretically predicted. In addition the distributions of spacings and radiative widths of the 2 - states are consistent with a Wigner and a Porter-Thomas distribution, respectively. (orig.)

Exact ∇{sup 4}R{sup 4} couplings and helicity supertraces

Energy Technology Data Exchange (ETDEWEB)

Bossard, Guillaume [Centre de Physique Théorique, Ecole Polytechnique, Université Paris-Saclay,91128 Palaiseau Cedex (France); Pioline, Boris [Laboratoire de Physique Théorique et Hautes Energies, CNRS UMR 7589,Université Pierre et Marie Curie,4 place Jussieu, 75252 Paris cedex 05 (France); CERN, Theoretical Physics Department,1211 Geneva 23 (Switzerland)

2017-01-12

In type II string theory compactified on a d-dimensional torus T{sup d} down to D=10−d dimensions, the R{sup 4} and ∇{sup 4}R{sup 4} four-graviton couplings are known exactly, for all values of the moduli, in terms of certain Eisenstein series of the U-duality group E{sub d}(ℤ). In the limit where one circle in the torus becomes large, these couplings are expected to reduce to their counterpart in dimension D+1, plus threshold effects and exponentially suppressed corrections corresponding to BPS black holes in dimension D+1 whose worldline winds around the circle. By combining the weak coupling and large radius limits, we determine these exponentially suppressed corrections exactly, and demonstrate that the contributions of 1/4-BPS black holes to the ∇{sup 4}R{sup 4} coupling are proportional to the appropriate helicity supertrace. Mathematically, our results provide the complete Fourier expansion of the next-to-minimal theta series of E{sub d+1}(ℤ) with respect to the maximal parabolic subgroup with Levi component E{sub d} for d≤6, and the complete Abelian part of the Fourier expansion of the same for d=7.

Nonambipolarity, orthogonal conductivity, poloidal flow, and torque

International Nuclear Information System (INIS)

Hulbert, G.W.; Perkins, F.W.

1989-02-01

Nonambipolar processes, such as neutral injection onto trapped orbits or ripple-diffusion loss of α-particles, act to charge a plasma. A current j/sub r/ across magnetic surfaces must arise in the bulk plasma to maintain charge neutrality. An axisymmetric, neoclassical model of the bulk plasma shows that these currents are carried by the ions and exert a j/sub r/B/sub θ/R/c torque in the toroidal direction. A driven poloidal flow V/sub θ/ = E/sub r/'c/B must also develop. The average current density is related to the radial electric field E/sub r/' = E/sub r/ + v/sub /phi//B/sub θ//c in a frame moving with the plasma via the orthogonal conductivity = σ/sub /perpendicular//E/sub r/', which has the value σ/sub /perpendicular// = (1.65ε/sup 1/2/)(ne 2 ν/sub ii//MΩ/sub θ/ 2 ) in the banana regime. If an ignited plasma loses an appreciable fraction Δ of its thermonuclear α-particles by banana ripple diffusion, then the torque will spin the plasma to sonic rotation in a time /tau//sub s/ ∼ 2/tau//sub E//Δ, /tau//sub E/ being the energy confinement time. 10 refs., 1 fig

Perturbation of the Electron Transport Mechanism by Proton Intercalation in Nanoporous TiO2 Films

Energy Technology Data Exchange (ETDEWEB)

Halverson, A. F.; Zhu, K.; Erslev, P. T.; Kim, J. Y.; Neale, N. R.; Frank, A. J.

2012-04-11

This study addresses a long-standing controversy about the electron-transport mechanism in porous metal oxide semiconductor films that are commonly used in dye-sensitized solar cells and related systems. We investigated, by temperature-dependent time-of-flight measurements, the influence of proton intercalation on the electron-transport properties of nanoporous TiO{sub 2} films exposed to an ethanol electrolyte containing different percentages of water (0-10%). These measurements revealed that increasing the water content in the electrolyte led to increased proton intercalation into the TiO{sub 2} films, slower transport, and a dramatic change in the dependence of the thermal activation energy (E{sub a}) of the electron diffusion coefficient on the photogenerated electron density in the films. Random walk simulations based on a microscopic model incorporating exponential conduction band tail (CBT) trap states combined with a proton-induced shallow trap level with a long residence time accounted for the observed effects of proton intercalation on E{sub a}. Application of this model to the experimental results explains the conditions under which E{sub a} dependence on the photoelectron density is consistent with multiple trapping in exponential CBT states and under which it appears at variance with this model.

Effective-medium theory for nonlinear magneto-optics in magnetic granular alloys: cubic nonlinearity

Energy Technology Data Exchange (ETDEWEB)

Granovsky, Alexander B. E-mail: granov@magn.ru; Kuzmichov, Michail V.; Clerc, J.-P.; Inoue, Mitsuteru

2003-03-01

We propose a simple effective-medium approach for calculating the effective dielectric function of a magnetic metal-insulator granular alloy in which there is a weakly nonlinear relation between electric displacement D and electric field E for both constituent materials of the form D{sub i}={epsilon}{sub i}{sup (0)}E{sub i} +{chi}{sub i}{sup (3)}|E{sub i}|{sup 2}E{sub i}. We assume that linear {epsilon}{sub i}{sup (0)} and cubic nonlinear {chi}{sub i}{sup (3)} dielectric functions are diagonal and linear with magnetization non-diagonal components. For such metal-insulator composite magneto-optical effects depend on a light intensity and the effective cubic dielectric function {chi}{sub eff}{sup (3)} can be significantly greater (up to 10{sup 3} times) than that for constituent materials. The calculation scheme is based on the Bergman and Stroud-Hui theory of nonlinear optical properties of granular matter. The giant cubic magneto-optical nonlinearity is found for composites with metallic volume fraction close to the percolation threshold and at a resonance of optical conductivity. It is shown that a composite may exhibit nonlinear magneto-optics even when both constituent materials have no cubic magneto-optical nonlinearity.

Role of Fe doping on structural and vibrational properties of ZnO nanostructures

Energy Technology Data Exchange (ETDEWEB)

Pandiyarajan, T.; Udayabhaskar, R.; Karthikeyan, B. [National Institute of Technology, Department of Physics, Tiruchirappalli (India)

2012-05-15

In this report, Raman and Fourier Transform Infrared (FTIR) measurements were carried out to study the phonon modes of pure and Fe doped ZnO nanoparticles. The nanoparticles were prepared by sol-gel technique at room temperature. The X-ray diffraction measurements reveal that the nanoparticles are in hexagonal wurtzite structure and doping makes the shrinkage of the lattice parameters, whereas there is no alteration in the unit cell. Raman measurements show both E{sub 2}{sup low} and E{sub 2}{sup High} optical phonon mode is shifted towards lower wave number with Fe incorporation and explained on the basis of force constant variation, stress measurements, respectively. In addition, Fe related local vibrational modes (LVM) were observed for higher concentration of Fe doping. FTIR spectra reveal a band at 444 cm{sup -1} which is specific to E{sub 1} (TO) mode; a red-shift of this mode in Fe doped samples and some surface phonon modes were observed. Furthermore, the observation of additional IR modes, which is considered to have an origin related to Fe dopant in the ZnO nanostructures, is also reported. These additional mode features can be regarded as an indicator for the incorporation of Fe ions into the lattice position of the ZnO nanostructures. (orig.)

Communication: Theoretical study of ThO for the electron electric dipole moment search

Energy Technology Data Exchange (ETDEWEB)

Skripnikov, L. V., E-mail: leonidos239@gmail.com; Petrov, A. N.; Titov, A. V. [Federal State Budgetary Institute “Petersburg Nuclear Physics Institute,” Gatchina, Leningrad district 188300 (Russian Federation); Department of Physics, Saint Petersburg State University, Saint Petersburg, Petrodvoretz 198904 (Russian Federation)

2013-12-14

An experiment to search for the electron electric dipole moment (eEDM) on the metastable H{sup 3}Δ{sub 1} state of ThO molecule was proposed and now prepared by the ACME Collaboration [ http://www.electronedm.org ]. To interpret the experiment in terms of eEDM and dimensionless constant k{sub T,} {sub P} characterizing the strength of the T,P-odd pseudoscalar–scalar electron–nucleus neutral current interaction, an accurate theoretical study of an effective electric field on electron, E{sub eff}, and a parameter of the T,P-odd pseudoscalar–scalar interaction, W{sub T,} {sub P}, in ThO is required. We report our results for E{sub eff} (84 GV/cm) and W{sub T,} {sub P} (116 kHz) together with the hyperfine structure constant, molecule frame dipole moment, and H{sup 3}Δ{sub 1} → X{sup 1}Σ{sup +} transition energy, which can serve as a measure of reliability of the obtained E{sub eff} and W{sub T,} {sub P} values. Besides, our results include a parity assignment and evaluation of the electric-field dependence for the magnetic g factors in the Ω-doublets of H{sup 3}Δ{sub 1}.

Spin-flip (p,n) reactions on 26Mg, 54Fe, and 56Fe at selected proton bombarding energies in the range of 17 to 25 MeV

International Nuclear Information System (INIS)

Aron, D.L.

1985-06-01

New data are presented for the 26 Mg(p,n) 26 Al reaction at E/sub p/ = 19.12 and 24.97 MeV, for the 54 Fe(p,n) 54 Co reaction at E/sub p/ = 17.20, 18.60, and 24.60 MeV, and for the 56 Fe(p,n) 56 Co reaction at E/sub p/ = 19.12 and 24.59 MeV. Data were taken with the LLNL Cyclograaff at 16 angles from 3.5 0 to 159.0 0 . A large detector at 23.8 0 with a long neutron flight path collected high resolution spectra. This large detector also collected separate 0 0 high resolution data on the 26 Mg and 56 Fe(p,n) reactions at E/sub p/ = 19 MeV. Absolute differential (p,n) cross sections were extracted for 1 + states in 26 Al, 54 Co, and 56 Co, for the 0 + isobaric analong state (IAS) in 54 Co and 56 Co, for a 2 + state in each residual nucleus, and for the 0.199 MeV 7 + state of 54 Co. No new experimental states were identified. Only relative cross sections were extracted at 0 0 . Experimental angle-integrated cross sections were obtained for all but one state. DWBA79 was used, with the G-matrix effective nucleon-nucleon interaction of Bertsch et al. (with the central triplet-odd component V/sub to/ = O) and the Livermore shell model wave functions to calculate differential (p,n) cross sections to 1 + states and to the 54 Co and 56 Co IAS. Normalization of the DWBA angle-integrated cross sections to measurements for the 54 Co and 56 Co IAS (at E/sub p/ = 24.6 MeV) yielded the renormalized V/sub tau/ = 21.4 +- 2.1 MeV. Normalization of the DWBA angle-integrated cross sections to measurements for the 24.6 MeV 54 Co and 56 Co 1 + states, coupled with the normalization of the wave functions to previously experimentally determined GT strength, yield the renormalized V/sub sigmatau/ = 12.3 +- 1.2 MeV. The experimental Gamow-Teller strength B(GT)/sub exp./ of the T = 1 26 Al state at 9.44 MeV was found to be 0.69; B(GT)/sub exp/ of the T = 1 26 Al state at 10.47 MeV was found to be 0.39

Crystallization study of Sn additive Se–Te chalcogenide alloys

Energy Technology Data Exchange (ETDEWEB)

Abdel-Rahim, M.A.; Gaber, A.; Abu-Sehly, A.A.; Abdelazim, N.M., E-mail: nana841@hotmail.co.uk

2013-08-20

Highlights: • The aim of the work deals with studying the crystallization kinetics by using different method. • Values of various kinetic parameters were calculated. • The results indicate that the rate of crystallization is related to the thermal stability and glass forming ability. - Abstract: Results of differential thermal analysis (DTA) under non-isothermal conditions of glasses Se{sub 90−x}Te{sub 10}Sn{sub x} (x = 0, 2.5, 5 and 7 at.%) are reported and discussed. The glass transition temperature (T{sub g}), the onset crystallization temperature (T{sub c}) and the peak temperature of crystallization (T{sub p}) were found to be dependent on the compositions and the heating rate. Values of various kinetic parameters such as activation energy of glass transition (E{sub g}), activation energy of crystallization (E{sub c}), rate constant (K{sub p}), Hurby number (H{sub r}) and the order parameter (n) were determined. For the present systems, the results indicate that the rate of crystallization is related to thermal stability and glass forming ability (GFA). According to the Avrami exponent (n), the results show a one dimensional growth for the composition Se{sub 90}Te{sub 10} and a three dimensional growth for the three other compositions. The crystalline phases resulting from DTA and (SEM) have been identified using X-ray diffraction.

Zinc-induced modification of the dynamical magnetic susceptibility in the superconducting state of YBa{sub 2}Cu{sub 3}O{sub 6+}{sub {ital x}} as revealed by inelastic neutron scattering

Energy Technology Data Exchange (ETDEWEB)

Sidis, Y.; Bourges, P.; Hennion, B. [Laboratoire Leon Brillouin, CEA-CNRS, Centre dEtudes de Saclay, 91191 Gif-sur-Yvette (France); Regnault, L.P. [Centre dEtudes Nucleaires de Grenoble, Departement de Recherche Fondamentale sur la Matiere Condensee, Service de Physique Statistique, Magnetisme et Supraconductivite, Groupe Magnetisme et Diffraction Neutronique, 85 X, 38041 Grenoble cedex (France); Villeneuve, R.; Collin, G. [Laboratoire Leon Brillouin, CEA-CNRS, Centre dEtudes de Saclay, 91191 Gif-sur-Yvette (France); Marucco, J.F. [Laboratoire des Composes Non-Stoechiometriques, CNRS URA 446, Batiment 415, Universite Paris Sud centre dOrsay, Orsay (France)

1996-03-01

Inelastic-neutron-scattering measurements have been performed to determine the imaginary part of the dynamical susceptibility, {chi}{double_prime}({ital Q},{omega}), of a YBa{sub 2}(Cu{sub 1{minus}{ital y}}Zn{sub {ital y}}){sub 3}O{sub 6.97} sample exhibiting a superconducting transition at {ital T}{sub {ital c}}=69 K. Zinc substitution induces striking modifications of the energy dependence of {chi}{double_prime}({ital Q},{omega}) but magnetic fluctuations remain peaked at the antiferromagnetic wave vector, {ital Q}{sub AF}, at all investigated energies. In the superconducting state of the zinc-free compound, {chi}{double_prime}({ital Q},{omega}) is restricted to a narrow energy range, {h_bar}{omega}=33{endash}47 meV, displaying a {ital spin} {ital gap} at {ital E}{sub {ital G}}=33 meV and a resonant enhancement at {ital E}{sub {tau}}=39 meV, both features vanishing upon heating up above {ital T}{sub {ital c}}. In the {ital y}=0.02 substituted sample in the superconducting state, there is still an energy band in the range 32{endash}47 meV but no clear resonance, and a signal is now observed in the low energy range, though the line shape of {chi}{double_prime}({ital Q},{omega}) indicates some reminiscence of the spin gap of the pure compound. {copyright} {ital 1996 The American Physical Society.}

Comparative study of the core level photoemission of the ZrB{sub 2} and ZrB{sub 12}

Energy Technology Data Exchange (ETDEWEB)

Huerta, L. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, 04510 Mexico D.F. (Mexico); Duran, A. [Centro de Nanociencias y Nanotecnologia, Universidad Nacional Autonoma de Mexico, Apartado Postal 2681, Ensenada, Baja California 22800 (Mexico); Falconi, R. [Division Academica de Ciencias Basicas, Universidad Juarez Autonoma de Tabasco, Cunduacan, Tabasco, CP 86690, AP 24 (Mexico); Flores, M. [Departamento de Ingenieria de Proyectos, CUCEI, Universidad de Guadalajara, AP 307, Zapopan Jal 45101 (Mexico); Escamilla, R., E-mail: rauleg@servidor.unam.m [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, 04510 Mexico D.F. (Mexico)

2010-05-01

X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) were used to investigate the binding energies and valence band for ZrB{sub 2} and ZrB{sub 12}. The Zr 3d and B 1s core levels were identified. The Zr 3d core level shows a spin-orbit split 3d{sub 5/2} and 3d{sub 3/2} while that for B 1s core level exhibited a single symmetric peak, these being typical of zirconium and boride signals. Comparing the Zr 3d and B 1s core levels with metallic Zr, B{sub 2}O{sub 3} and ZrO{sub 2} reference materials only a negative chemical shift for Zr 3d associated to ZrB{sub 2} was observed, which suggests that the charge transfer model based on the concept of electronegativity was not applicable to explain the superconductivity in the ZrB{sub 12} sample. The measured valence band using UPS is consistent with the band-structure calculations indicating a higher density of states (DOS) at E{sub F} for ZrB{sub 12} respect to ZrB{sub 2}. Finally, we found that the weak mixed B-p and Zr-d states for ZrB{sub 12} is crucial for the superconductivity due to the state population increased the DOS at the E{sub F}.

Erbium concentration dependent absorbance in tellurite glass

Energy Technology Data Exchange (ETDEWEB)

Sazali, E. S., E-mail: mdsupar@utm; Rohani, M. S., E-mail: mdsupar@utm; Sahar, M. R., E-mail: mdsupar@utm; Arifin, R., E-mail: mdsupar@utm; Ghoshal, S. K., E-mail: mdsupar@utm; Hamzah, K., E-mail: mdsupar@utm [Advanced Optical Material Research Group, Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, 81310, Skudai, Johor Bahru, Johor (Malaysia)

2014-09-25

Enhancing the optical absorption cross-section in topically important rare earth doped tellurite glasses is challenging for photonic devices. Controlled synthesis and detailed characterizations of the optical properties of these glasses are important for the optimization. The influence of varying concentration of Er{sup 3+} ions on the absorbance characteristics of lead tellurite glasses synthesized via melt-quenching technique are investigated. The UV-Vis absorption spectra exhibits six prominent peaks centered at 490, 526, 652, 800, 982 and 1520 nm ascribed to the transitions in erbium ion from the ground state to the excited states {sup 4}F{sub 7/2}, {sup 2}H{sub 11/2}, {sup 4}F{sub 9/2}, {sup 4}I{sub 9/2}, {sup 2}H{sub 11/2} and {sup 4}I{sub 13/2}, respectively. The results are analyzed by means of optical band gap E{sub g} and Urbach energy E{sub u}. The values of the energy band gap are found decreased from 2.82 to 2.51 eV and the Urbach energy increased from 0.15 to 0.24 eV with the increase of the Er{sub 2}O{sub 3} concentration from 0 to 1.5 mol%. The excellent absorbance of the prepared tellurite glasses makes them suitable for fabricating solid state lasers.

Determination of optical constant and dispersion parameters of Se{sub 75}Sb{sub 10}In{sub 15} thin film characterized by wide band gap

Energy Technology Data Exchange (ETDEWEB)

Abd-Elrahman, M.I.; Abu-Sehly, A.A.; El-sonbaty, Sherouk Sh.; Hafiz, M.M. [Assiut University, Physics Department, Faculty of Science, Assiut (Egypt)

2017-02-15

Chalcogenide Se{sub 75}Sb{sub 10}In{sub 15} thin films of different thickness (50-300 nm) are deposited using thermal evaporation technique. The thermogram of the chalcogenide bulk Se{sub 75}Sb{sub 10}In{sub 15} is obtained using a differential scanning calorimetry (DSC). The crystallization temperature T{sub c}, peak crystallization temperature T{sub p} and melting temperature T{sub m}, are identified. The X-ray diffraction (XRD) examination indicates the crystallinity of the as-deposited film decreases with increasing of thickness. Optical transmission and reflection spectra are recorded in the wavelength range of the incident photons from 250 to 2500 nm. It is found that the film thickness affects the absorption coefficient, refractive index, extinction coefficient and the width of the tails of localized states in the gap region. The absorption mechanism of the as-deposited films is a direct allowed transition. The optical band gap energy (E{sub g}) decreases from 3.31 to 2.51 eV with increasing the film thickness from 50 to 300 nm. The behavior of E{sub g} is explained on the basis of the structure disorders in the thicker films. The effect of the film thickness on the single-oscillator and dispersion energies is studied by the dispersion analyses of the refractive index. (orig.)

A role of prostaglandin E/sub2/ in radiation-induced hyperthermia

International Nuclear Information System (INIS)

Cernak, I.; Stanimirovic, D.; Simovic, M.; Ivanovic, L.; Markovic, M.; Savic, J.

1989-01-01

Radiation-induced (6.7 Gy X-ray) changes in body temperature were investigated in rats exposed to: whole body irradiation pretreatment with indomethacin (5 mg/kg b.w.) 30 min before whole body irradiation and irradiation of the body with protected head. Content of prostaglandin E 2 (PGE 3 ) was measured in the rat brain hypothalamic regions and compared to correspondent body temperature. Hypothalamic PGE 2 content strongly correlated with body temperature (r=0.79, p 2 in the hypothalamus is presumed as a putative mediator of radiation-induced changes in body temperature. (author). 8 refs.; 2 figs.; 1 tab

Quadrupole hyperfine structure and splitting of Δ-levels in the microwave spectra of KOH, RbOH and CsOH in the 100 GHz region

International Nuclear Information System (INIS)

Kuijpers, P.; Dymanus, A.; Toerring, T.

1977-01-01

Hyperfine structure of rotational transitions of KOH, RbOH and CsOH in various v 2 - and l-states has been carefully measured in the 100 GHz range. From the observed splittings and broadenings information about quadrupole coupling constant (eqQ) of the K nucleus in KOH and about the spacing (Esub(Δ) - Esub(Σ)) between Σ and Δ levels in the vibrational spectrum of KOH, RbOH and CsOH has been derived. The measured value of the eqQ of KOH is close to that of KF. The separation between Σ and Δ levels is found to be rather similar for the group of the alkali hydroxides increasing gradually when progressing from LiOH to CsOH. (orig.) [de

Parameters of compensating centers in n-type Si highly compensated by irradiation. Parametry kompensiruyushchikh tsentrov v n-Si sil'no kompensirovannym oblucheniem

Energy Technology Data Exchange (ETDEWEB)

Klinger, P M; Fistul' , V I [Moskovskij Gosudarstvennyj Univ., Moscow (USSR)

1990-06-01

Resuls of investigations into effect of {gamma}- and neutron irradiation on defect formation in high-ohmic n-Si

using technique of capacity temperature dependence (CTD) are given. Radiation dose varied from 4.8x10{sup 17} up to 1.7x10{sup 18} cm{sup -2}. CTD technique is shown to be successfully applied to investigate into defect formation at irradiation of highly compensated silicon. Rate of admission of Ec-0.40 eV deep acceptor levels in n-Si at pulsed electron irradiation does not depend on fine impurity cocentration. Positions of energy levels of deep acceptors introduced into n-Si do not coincide and constitute, respectively, E{sub c}-0.40 and E{sub c}-049 eV.

RIA system programming by means of kinetic parameters

Energy Technology Data Exchange (ETDEWEB)

Silberring, J; Golda, W [Akademia Medyczna, Krakow (Poland). Dept. of Endocrinology and Metabolism

1979-12-01

Insulin-/sup 125/I antibody reaction was optimized by physical-chemical parameters. After the activation energies Esub(a) and Esub(d)-for association and association, respectively were calculated from the experimental data, the theoretical values of the reaction rate constants ksub(a) and ksub(d) were determined as well as equilibrium constants K. By means of the empirical formulae, the approximate incubation time for the RIA kit and maximal percent of insulin-/sup 125/I binding to antibody (%B) in relation to temperature were computed. The proposed method may be applied to the new antigen-binder systems preparation (new antibodies, shortening of the incubation time, temperature changes, influence of different ions and kind of buffer). (orig.) 891 MG/orig. 892 MBE.

Intrinsic electron traps in atomic-layer deposited HfO{sub 2} insulators

Energy Technology Data Exchange (ETDEWEB)

Cerbu, F.; Madia, O.; Afanas' ev, V. V.; Houssa, M.; Stesmans, A. [Laboratory of Semiconductor Physics, Department of Physics and Astronomy, University of Leuven, 3001 Leuven (Belgium); Andreev, D. V. [Laboratory of Semiconductor Physics, Department of Physics and Astronomy, University of Leuven, 3001 Leuven (Belgium); Bauman Moscow State Technical University—Kaluga Branch, 248000 Kaluga, Moscow obl. (Russian Federation); Fadida, S.; Eizenberg, M. [Department of Materials Science and Engineering, Technion-Israel Institute of Technology, 32000 Haifa (Israel); Breuil, L. [imec, 3001 Leuven (Belgium); Lisoni, J. G. [imec, 3001 Leuven (Belgium); Institute of Physics and Mathematics, Faculty of Science, Universidad Austral de Chile, Valdivia (Chile); Kittl, J. A. [Laboratory of Semiconductor Physics, Department of Physics and Astronomy, University of Leuven, 3001 Leuven (Belgium); Advanced Logic Lab, Samsung Semiconductor, Inc., Austin, 78754 Texas (United States); Strand, J.; Shluger, A. L. [Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom)

2016-05-30

Analysis of photodepopulation of electron traps in HfO{sub 2} films grown by atomic layer deposition is shown to provide the trap energy distribution across the entire oxide bandgap. The presence is revealed of two kinds of deep electron traps energetically distributed at around E{sub t} ≈ 2.0 eV and E{sub t} ≈ 3.0 eV below the oxide conduction band. Comparison of the trapped electron energy distributions in HfO{sub 2} layers prepared using different precursors or subjected to thermal treatment suggests that these centers are intrinsic in origin. However, the common assumption that these would implicate O vacancies cannot explain the charging behavior of HfO{sub 2}, suggesting that alternative defect models should be considered.

Pulse radiolysis of ethanolic solutions of rhodamine dyes

International Nuclear Information System (INIS)

Kartasheva, L.I.; Kucherenko, E.A.; Kozlov, A.S.; Pikaev, A.K.

1983-01-01

The primary products of radiolytical transformations of rhodamine 6G, rhodamine B, rhodamine 3B and rhodamine 110 in ethanolic solutions were studied by pulse radiolysis method under various conditions. It was found that the semireduced form of a dye was the only intermediate product of such transformations in ethanolic solutions of all dyes. It was shown that this species was formed by interaction of the dye with esub(s) - and CH 3 CHOH. The properties of this species were investigated and the rate constants of respective reactions for each dye were determined. It was found that nature and position of a substituent in the molecule of the dye have an effect on the rate of formation of the semi-reduced form. (author)

Measurement of dijet cross sections for events with a leading neutron in photoproduction at HERA

Energy Technology Data Exchange (ETDEWEB)

Breitweg, J.; Chekanov, S.; Derrick, M.; Krakauer, D.; Magill, S.; Musgrave, B.; Pellegrino, A.; Repond, J.; Stanek, R.; Yoshida, R.; Mattingly, M.C.K.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cara Romeo, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; De Pasquale, S.; Giusti, P.; Iacobucci, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Palmonari, F.; Pesci, A.; Sartorelli, G.; Zichichi, A.; Amelung, C.; Bornheim, A.; Brock, I.; Coboeken, K.; Crittenden, J.; Deffner, R.; Hartmann, H.; Heinloth, K.; Hilger, E.; Irrgang, P.; Jakob, H.-P.; Kappes, A.; Katz, U.F.; Kerger, R.; Paul, E.; Rautenberg, J.; Schnurbusch, H.; Stifutkin, A.; Tandler, J.; Voss, K.C.; Weber, A.; Wieber, H.; Bailey, D.S.; Barret, O.; Brook, N.H.; Foster, B. E-mail: b.foster@bristol.ac.uk; Heath, G.P.; Heath, H.F.; Rodrigues, E.; Scott, J.; Tapper, R.J.; Capua, M.; Schioppa, M.; Susinno, G.; Jeoung, H.Y.; Kim, J.Y.; Lee, J.H.; Lim, I.T.; Ma, K.J.; Pac, M.Y.; Caldwell, A.; Liu, W.; Liu, X.; Mellado, B.; Paganis, S.; Sampson, S.; Schmidke, W.B.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Klimek, K.; Olkiewicz, K.; Piotrzkowski, K.; Przybycien, M.B.; Stopa, P.; Zawiejski, L.; Bednarek, B.; Jelen, K.; Kisielewska, D.; Kowal, A.M.; Kowalski, T.; Przybycien, M.; Rulikowska-Zarebska, E.; Suszycki, L.; Szuba, D.; Kotanski, A.; Bauerdick, L.A.T.; Behrens, U.; Bienlein, J.K.; Borras, K.; Chiochia, V.; Dannheim, D.; Desler, K.; Drews, G.; Fox-Murphy, A.; Fricke, U.; Goebel, F.; Goers, S.; Goettlicher, P.; Graciani, R.; Haas, T.; Hain, W.; Hartner, G.F.; Hebbel, K.; Hillert, S.; Koch, W.; Koetz, U.; Kowalski, H.; Labes, H.; Loehr, B.; Mankel, R.; Martens, J.; Martinez, M.; Milite, M.; Moritz, M.; Notz, D.; Petrucci, M.C.; Polini, A.; Rohde, M.; Savin, A.A.; Schneekloth, U.; Selonke, F.; Sievers, M.; Stonjek, S.; Wolf, G.; Wollmer, U.; Youngman, C.; Zeuner, W.; Coldewey, C.; Lopez-Duran Viani, A.; Meyer, A.; Schlenstedt, S.[and others

2001-02-26

Differential cross sections for dijet photoproduction in association with a leading neutron using the reaction e{sup +}+p{yields}e{sup +}+n+jet+jet+X{sub r} have been measured with the ZEUS detector at HERA using an integrated luminosity of 6.4 pb{sup -1}. The fraction of dijet events with a leading neutron in the final state was studied as a function of the jet kinematic variables. The cross sections were measured for jet transverse energies E{sub T}{sup jet}>6 GeV, neutron energy E{sub n}>400 GeV, and neutron production angle {theta}{sub n}<0.8 mrad. The data are broadly consistent with factorization of the lepton and hadron vertices and with a simple one-pion-exchange model.

Study of high spin states in 68Zn and 68Ga using (α,pγ) and (α,nγ) reactions

International Nuclear Information System (INIS)

Berthet, Bernard.

1976-01-01

Yrast levels of 68 Zn and 6 Ga have been studied via the reactions 65 Cu(α,pγ) 68 Zn, 65 Cu(α,nγ) 68 Ga at Esub(α)=12-21MeV and 66 Zn(α,pnγ) 68 Ga at Esub(α)=25-40MeV. The level schemes have been established by means of relative yield functions, electronic timing measurements, prompt and delayed γ-γ coincidences, angular distributions and directional orientation coincidences. Spin up to 8 were assigned to observed states, for 68 Zn. For 68 Ga, spins up to 11 + were assigned to level up to 4MeV excitation and the higher ones were interpreted by coupling a 67 Ga core with a 1gsub(9/2) neutron [fr

Search for photinos in e/sup +/e/sup -/ annihilation

Energy Technology Data Exchange (ETDEWEB)

Ellis, J; Hagelin, J S [Stanford Linear Accelerator Center, CA (USA). Theory Group

1983-03-10

We discuss the pair production of massive photinos or other neutral gauginos in e/sup +/e/sup -/ annihilation. We present cross sections for e/sup +/e/sup -/->..gamma gamma.. and e/sup +/e/sup -/->..gamma gamma gamma.. including finite mass effects for both the selectron and the gaugino. Experimental signatures are a possible pair of photons from ..gamma.. decay each with <Esub(..gamma..)>=1/4Esub(cm) and a single soft photon in the case of radiative pair production. We exhibit the domains of selectron and gaugino masses and of the supersymmetry breaking scale parameter that could be probed by dedicated searches, pointing out that the present PETRA and PEP centre-of-mass energies are nearly ideal for light gaugino hunts.

Collective processes in heavy-ion collisions with atomic nuclei. Dissipation of energy and angular momentum

International Nuclear Information System (INIS)

Kuzminski, J.

1980-01-01

The collective processes in collision of heavy-ions with atomic nuclei are discussed. Measured data on the S+Ti collision at Esub(LAB)=105, 130 and 144 MeV have been analysed in terms of a ''fission-like'' processes which seem to be a special case of deep inelastic collisions whose total available kinetic energy is completely dissipated. Applying transport theory it was possible to introduce a ''clock'' for measuring the time scale of nuclear processes in collision of heavy-ions by measuring the FWHM of mass distribution of emitted reaction products. Experimental data on continuum gamma spectra from Cu+Au collision at Esub(LAB)=400 MeV are presented and the angular momentum dissipation in this reaction is discussed. (author)

Destruction of /sup 18/O in red giants. A search for a sub-threshold resonance in the /sup 18/O+p system

Energy Technology Data Exchange (ETDEWEB)

Champagne, A E; Pitt, M L

1986-09-08

The /sup 18/O(/sup 3/He,d)/sup 19/F reaction has been used to determine if a presumed sub-threshold resonance at Esub(c.m.)=-94 KeV in the /sup 18/O(p,..cap alpha..)/sup 15/N reaction exists at an astrophysically significant level. No evidence for this state was observed which implies a dimensionless reduced width thetasub(p)/sup 2/<5 . 10/sup -5/. In addition, a proton width GAMMAsub(p)=2 x 10/sup -19/ eV has been determined for a d-wave resonance located at Esub(c.m.)=20 keV. The resulting thermonuclear reaction rate is slow enough to ensure that /sup 18/O is not destroyed at red-giant temperatures.

The pulse radiolysis of aqueous solutions of simple RCN compounds

International Nuclear Information System (INIS)

Draganic, I.G.; Draganic, Z.D.; Markovic, V.M.

1976-01-01

Fast kinetic spectrophotometry was used to study the absorption spectra of short-living intermediates produced by reactions of RCN molecules with H, esub(aq) - and OH. The spectra were obtained on the microsecond time scale after an electron pulse from a Febetron 707 accelerator in aqueous solutions of the following compounds: hydrocyanic acid, acetonitrile, propionitrile, malononitrile and succinonitrile. It has been found that all intermediates absorb in the U.V. range (lamba 9 dm 3 mol -1 s -1 . In the presence of an efficient scavenger for hydroxyl radicals, the same transient spectra were registered in acid and neutral solutions suggesting that the protonations of esub(aq) - adducts of these RCN molecules were complete within a submicrosecond time interval. (author)

Crystal structures and thermodynamics/kinetics of Zn(II) coordination polymers with helical chains

Energy Technology Data Exchange (ETDEWEB)

He, Tian [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China); Yue, Ke-Fen, E-mail: ykflyy@nwu.edu.cn [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China); Zhao, Yi-xing; Chen, San-Ping [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China); Zhou, Chun-sheng, E-mail: slzhoucs@126.com.cn [Shaanxi Key Laboratory of Comprehensive Utilization of Tailings Resources, College of Chemical Engineering and Modern Materials, Shangluo University, Shangluo 726000 (China); Yan, Ni [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710069 (China)

2016-07-15

Solvothermal reactions of Zn(II) acetates and four V-shaped carboxylates ligands in the presence of 1,4-Bis(2-methyl-imidazol-1-yl)butane afforded four interesting Zn(II) coordination polymers with helical chains, namely, {[Zn(bib)(atibdc)]·2H_2O}{sub n} (1), {[Zn(bib)(atbip)]·H_2O}{sub n} (2), {[Zn(bib)(2,2′-tda)]}{sub n} (3) and {[Zn(bib)(5-tbipa)]·EtOH}{sub n} (4), (H{sub 2}atibdc=5-amino-2,4,6-triiodoisophthalic acid, H{sub 2}atbip=5-amino-2,4,6-tribromoisophthalic acid, 2,2′-H{sub 2}tad=2,2′-thiodiacetic acid, 5-H{sub 2}tbipa=5-tert-butyl-isophthalic acid). 1 reveals a 3D chiral framework with three kinds of helical chains along a, b and c axis. 2 shows a 2D step-type chiral framework with right-handed helical chains. 3 displays a wavelike 2D layer network possessing alternate left- and right-handed helical chains. 4 presents a four-connected 3D framework with zigzag and meso-helical chains. The different spacers and substituent group of carboxylic acid ligands may lead to the diverse network structures of 1–4. The fluorescent properties of complexes 1−4 were studied. In addition, the thermal decompositions properties of 1–4 were investigated by simultaneous TG/DTG–DSC technique. The apparent activation energy E and the pre-exponential factor (A) of skeleton collapse for the complexes 1–4 are calculated by the integral Kissinger's method and Ozawa–Doyle's method. The activation energy E (E{sub 1}=209.658 kJ·mol{sup −1}, E{sub 2}=250.037 kJ mol{sup −1}, E{sub 3}=225.300 kJ mol{sup −1}, E{sub 4}=186.529 kJ·mol{sup −1}) demonstrates that the reaction rate of the melting decomposition is slow. The thermodynamic parameters (ΔH{sup ‡}, ΔG{sup ‡} and ΔS{sup ‡}) at the peak temperatures of the DTG curves were also calculated. ΔG{sup ‡}>0 indicates that the skeleton collapse is not spontaneous. ΔH{sub d}>0 suggests that the skeleton collapse is endothermic, corresponding to the intense endothermic peak of the DSC

Peak regulation right

International Nuclear Information System (INIS)

Gao, Z. |; Ren, Z.; Li, Z.; Zhu, R.

2005-01-01

A peak regulation right concept and corresponding transaction mechanism for an electricity market was presented. The market was based on a power pool and independent system operator (ISO) model. Peak regulation right (PRR) was defined as a downward regulation capacity purchase option which allowed PRR owners to buy certain quantities of peak regulation capacity (PRC) at a specific price during a specified period from suppliers. The PRR owner also had the right to decide whether or not they would buy PRC from suppliers. It was the power pool's responsibility to provide competitive and fair peak regulation trading markets to participants. The introduction of PRR allowed for unit capacity regulation. The PRR and PRC were rated by the supplier, and transactions proceeded through a bidding process. PRR suppliers obtained profits by selling PRR and PRC, and obtained downward regulation fees regardless of whether purchases are made. It was concluded that the peak regulation mechanism reduced the total cost of the generating system and increased the social surplus. 6 refs., 1 tab., 3 figs

Alpha particle spectroscopy for CR-39 detector utilizing matrix of energy equations

Energy Technology Data Exchange (ETDEWEB)

Awad, E.M. [Department of General Sciences, Yanbu Industrial College, PO Box 30436, Madinat Yanbu Al-Sinaiya (Saudi Arabia); Physics Department, Faculty of Science, Menofia University, Shebin El-Koom (Egypt)], E-mail: ayawad@yahoo.com; Soliman, A.A. [Department of Mathematics, Faculty of Education (AL-Arish), Suez Canal University, AL-Arish 45111 (Egypt); Department of Mathematics, Teacher' s College (Bisha), King Khalid University, Bisha, PO Box 551 (Saudi Arabia)], E-mail: asoliman_99@yahoo.com; Rammah, Y.S. [Physics Department, Faculty of Science, Menofia University, Shebin El-Koom (Egypt)

2007-10-01

A method for determining alpha-particle energy using CR-39 detector by utilizing matrix of energy equation was described. The matrix was composed from two axes; the track minor axis (m) and diameter of etched out track end (d) axis of some selected elliptical tracks. The energy E in (m,d) coordinate was approximated by matrix of energy equations given by: E{sub k}={sigma}{sub i,j=0}{sup 2}a{sub ij}d{sub k}{sup i}m{sub k}{sup j}, which was identified using two different approaches. First, i and j were treated as power exponents for d and m. The adjusting parameters values a{sub ij} were obtained and the energy of a given track was deduced directly from it. Second, i and j were treated as indices of some chosen tracks that were fitted to obtain iso-energy curves that were superimposed on m-d scatter plot as calibration curves. The energy between any two successive iso-energy curves in this case was assumed varied linearly with d for a given m. The energy matrix in both cases was solved numerically. Results of the two approaches were compared.

Study of oxidation-reduction reactions of plutonium and neptunium in sulphuric-phosphoric acid media

International Nuclear Information System (INIS)

Moiseev, I.V.; Kuperman, A.Ya.; Borodina, N.N.; Galkina, V.N.; Vinokurov, V.A.

1976-01-01

Potentiostatic, coulometric, potentiometric, and amperometric methods have been used for determining the rate constants of disproportionation (ksub(d)) of plutonium(5) and neptunium (5) and normal real redox potentials (Esub(0)sup(p)) of the following ion pairs in sulphur-phosphoric-acid media: PuOsub(2)sup(2)sup(+) (PuO 2 + , Pu 4+ /Pu 3+ , NpO 2 2+ /NpO 2 + , NpO 2 2+ /Np 4+ , NpO 2 + /Np 4+ , and Fe 3+ /Fe 2+ . The regularities have been shown of changing ksub(d) and Esub(o)sup(p) as a function of H 2 SO 4 and H 3 PO 4 concentration. It has been established that for plutonium and neptunium a linear correlation is observed between lg ksub(d) and Esub(o)sup(p) of the ion pairs NpO 2 2+ /NpO 2 + , NpO 2 2 /Np 4+ , NpO 2 + /Np 4+ and PuO 2 2+ /PuO 2 + in a wide range of their values. The correlation coefficient is close to unity in all cases (no less than 0.96). The results of investigations have made it possible to recommend optimum compositions of background electrolytes for performing continuous amperostatic coulometric titration of Pusup((6)) and Npsup((6)) up to four valent state by electrogenerated ions of iron (2)

Productivity of whole-tree bundler in energy wood and pulpwood harvesting from early thinnings

Energy Technology Data Exchange (ETDEWEB)

Nuutinen, Yrjoe; Laitila, Juha (Finnish Forest Research Inst., Joensuu (Finland)), e-mail: Yrjo.Nuutinen@metla.fi; Kaerhae, Kalle; Keskinen, Sirkka (Metsaeteho Oy, Helsinki (Finland)); Jylhae, Paula (Finnish Forest Research Inst., Kannus (Finland))

2011-06-15

First thinnings have been neglected to great extent in Finland because of high harvesting costs. The whole-tree bundler (Fixteri) was developed in order to rationalize the integrated harvesting of small-diameter energy wood and pulpwood and to reduce transportation costs through load compaction. The operation of the whole-tree bundler is composed of cutting and compaction processes. In the present study, the productivity level and the performance characteristics of the second version of the whole-tree bundler (Fixteri II) in integrated energy wood and pulpwood harvesting from first thinnings were defined on the basis of a time study. When the mean volume of removed whole trees averaged 20 dm3 at the stand, the productivity of Fixteri II per effective working (E{sub 0} excluding delays) hour was 3.4 m3/(E{sub 0}) and with an average removal of 75 dm3, it was 6.1 m3/(E{sub 0}). When compared with the first prototype of the whole-tree bundler (Fixteri I), the productivity of Fixteri II was 38-77% higher, depending on the stand density and mean tree volume of the removal. The higher performance level of Fixteri II stemmed mainly from the increase in multi-tree cutting and from the introduction of grapple feeding of the bunches. Furthermore, the better hydraulic capacity of the base machine enabled a higher level of simultaneous working processes

Monte Carlo simulation of the HEGRA cosmic ray detector performance

Energy Technology Data Exchange (ETDEWEB)

Martinez, S. [Universidad Complutense de Madrid (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Arqueros, F. [Universidad Complutense de Madrid (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Fonseca, V. [Universidad Complutense de Madrid (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Karle, A. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D80805 Munich (Germany); Lorenz, E. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D80805 Munich (Germany); Plaga, R. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D80805 Munich (Germany); Rozanska, M. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D80805 Munich (Germany)]|[Institute of Nuclear Physics, ul.Kawiory 26a, PL30-055 Cracow (Poland)

1995-04-21

Models of the scintillator and wide-angle air Cherenkov (AIROBICC) arrays of the HEGRA experiment are described here. Their response to extensive air showers generated by cosmic rays in the 10 to 1000 TeV range has been assessed using a detailed Monte Carlo simulation of air shower development and associated Cherenkov emission. Protons, {gamma}-rays and oxygen and iron nuclei have been considered as primary particles. For both arrays, the angular resolution as determined from the Monte Carlo simulation is compared with experimental data. Shower size N{sub e} can be reconstructed from the scintillator signals with an error ranging from 10% (N{sub e}=2x10{sup 5}) to 35% (N{sub e}=3x10{sup 3}). The energy threshold of AIROBICC is 14 TeV for primary gammas and 27 TeV for protons and an angular resolution of 0.25 can be obtained. The measurement of the Cherenkov light at 90 m from the shower core provides an accurate determination of primary energy E{sub 0} as far as the nature of the primary particle is known. For gammas an error in the energy prediction ranging from 8% (E{sub 0}=5x10{sup 14} eV) to 15% (E{sub 0}=2x10{sup 13} eV) is achieved. This detector is therefore a powerful tool for {gamma}-ray astronomy. ((orig.)).

A case of internal contamination with plutonium oxide

International Nuclear Information System (INIS)

Breuer, F.; Clemente, G.F.; Strambi, E.; Testa, C.

1980-01-01

A case is described of internal contamination caused by the accidental explosion of a glove box, whereby a technician was wounded in his right cheek and inhaled insoluble PuO 2 . Immediate washing of the wound with a DTPA solution and the performance of a small surgical toilet reduced the wound contamination a hundred times. Intravenous injection of DPTA was started and continued for nine days. The ''in vivo'' determination of plutonium and Am-241 lung content was performed immediately after the accident and several other times thereafter. Plutonium was determined periodically in urine and fecal samples for five months. The large Esub(f)/Esub(u) ratio and the steep slope of the Esub(f) curve in the first days indicated that the inhaled material was very insoluble and that the suspended powder particles were large. This conclusion was confirmed by the lung clearance ''in vivo'' during the first few days. The initial lung burden, calculated by the fecal excretion of plutonium in the first five days, was in very good agreement with the direct measurement of the lung content; the residual lung burden and the systemic burden were derived respectively U by the fecal and urinary excretion 100 days after the intake. The committed doses to lungs, bone, liver and kidneys were calculated and were found to be considerably lower than the maximum permissible levels. (H.K.)

Transverse electron resonance accelerator

International Nuclear Information System (INIS)

Csonka, P.L.

1985-01-01

Transverse (to the velocity, v, of the particles to be accelerated) electron oscillations are generated in high (e.g. solid) density plasmas by either an electromagnetic wave or by the field of charged particles traveling parallel to v. The generating field oscillates with frequency ω = ω/sub p/, where ω/sub p/ is the plasma frequency. The plasma is confined to a sequence of microstructures with typical dimensions of d approx. = 2πc/ω/sub p/, allowing the generating fields to penetrate. Since ω/sub p/ is now high, the time scales, T, are correspondingly reduced. The microstructures are allowed to explode after t = T, until then they are confined by ion inertia. As a result of resonance, the electric field, E, inside the microstructures can exceed the generating field E/sub L/. The generating force is proportional to E/sub L/ (as opposed to E/sub L/ 2 ). Phase matching of particles is possible by appropriate spacing of the microstructures or by a gas medium. The generating beam travels outside the plasma, filamentation is not a problem. The mechanism is relatively insensitive to the exact shape and position of the microstructures. This device contains features of various earlier proposed acceleration mechanisms and may be considered as the limiting case of several of those for small d, T and high E

Diesel exhaust particulate extracts inhibit transcription of nuclear respiratory factor-1 and cell viability in human umbilical vein endothelial cells

Energy Technology Data Exchange (ETDEWEB)

Mattingly, Kathleen A.; Klinge, Carolyn M. [University of Louisville School of Medicine, Department of Biochemistry and Molecular Biology, Center for Genetics and Molecular Medicine, Louisville, KY (United States)

2012-04-15

Endothelial dysfunction precedes cardiovascular disease and is accompanied by mitochondrial dysfunction. Here we tested the hypothesis that diesel exhaust particulate extracts (DEPEs), prepared from a truck run at different speeds and engine loads, would inhibit genomic estrogen receptor activation of nuclear respiratory factor-1 (NRF-1) transcription in human umbilical vein endothelial cells (HUVECs). Additionally, we examined how DEPEs affect NRF-1-regulated TFAM expression and, in turn, Tfam-regulated mtDNA-encoded cytochrome c oxidase subunit I (COI, MTCO1) and NADH dehydrogenase subunit I (NDI) expression as well as cell proliferation and viability. We report that 17{beta}-estradiol (E{sub 2}), 4-hydroxytamoxifen (4-OHT), and raloxifene increased NRF-1 transcription in HUVECs in an ER-dependent manner. DEPEs inhibited NRF-1 transcription, and this suppression was not ablated by concomitant treatment with E{sub 2}, 4-OHT, or raloxifene, indicating that the effect was not due to inhibition of ER activity. While E{sub 2} increased HUVEC proliferation and viability, DEPEs inhibited viability but not proliferation. Resveratrol increased NRF-1 transcription in an ER-dependent manner in HUVECs, and ablated DEPE inhibition of basal NRF-1 expression. Given that NRF-1 is a key nuclear transcription factor regulating genes involved in mitochondrial activity and biogenesis, these data suggest that DEPEs may adversely affect mitochondrial function leading to endothelial dysfunction and resveratrol may block these effects. (orig.)

The acute effects of different energy beta-emitters on pig and mouse skin

International Nuclear Information System (INIS)

Hopewell, J.W.; Hamlet, R.; Wells, J.; Charles, M.W.

1986-01-01

Acute changes were studied in the skin of mice and pigs following irradiation with Sr 90 (Esub(max) 2.27 MeV), Tm 170 (Esub(max) 0.97 MeV) and Pm 147 (Esub(max) 0.225 MeV). Sr 90 irradiation in the pig and Sr 90 and Tm 170 exposure in the mouse resulted in a distinct field-size effect for sources of 5-22.5 mm diameter; ED 50 values for moist desquamation were 22.0-27.5 Gy from the 22.5 mm source and 75-90 Gy for the 5 mm source. Tm 170 irradiation in the pig produced no distinct area effect for sources of 5-19 mm diameter (ED 50 approx.= 80 Gy). Acute tissue breakdown was only achieved in pig and mouse skin by very high doses (ED 50 >= 140 Gy) from sources of 147 produced acute epithelial breakdown, only after high skin-surface doses (ED 50 550-725 Gy). Area-and energy-related changes can, in part be explained by an hypothesis based on repopulation of the epithelium in the irradiated area by the migration of either cells from the edge of that area and/or cells surviving at the base of hair follicles. Differences in the results in pig and mouse can be explained on the basis of the distribution of target cells in the epidermis at varying depths. (author)

Photons, missing energy and the quest for supersymmetry at the LHC

Energy Technology Data Exchange (ETDEWEB)

Gebbert, Ulla

2012-03-15

In this thesis a search for supersymmetry in events with at least one photon, jets and missing transverse energy (E{sub T}) in an integrated luminosity of 4.32 fb{sup -1} of pp collisions at {radical}(s)=7 TeV is presented. The data is recorded by the CMS detector in 2011. Final states with photons are expected in models with gauge mediated supersymmetry breaking, where the lightest supersymmetric particle is the gravitino. The gravitino leaves the detector without energy deposition and thus leads to missing transverse momentum in the event. E{sub T} is crucial to distinguish the signal from the Standard Model events and is reconstructed from all energy deposits in the detector. Due to the non-linearity of the response in the calorimeter, additional corrections are required. In this thesis, a data driven technique to determine the correction for unclustered energy deposits, using the transverse momentum balance between a Z boson and the hadronic recoil, is presented. For the search for supersymmetry the E{sub T} distribution measured in data is compared to the expected Standard Model distribution. For this purpose the main Standard Model background processes from QCD multi- and photon-jet or electro-weak processes are modelled using data events. No excess over the Standard Model expectation is observed. Exclusion limits at the 95% CL are set and interpreted in the GMSB parameter space.

Observation of self-organized criticality (SOC) behavior during edge biasing experiment on TEXTOR

Energy Technology Data Exchange (ETDEWEB)

Xu, Y.H.; Jachmich, S.; Weynants, R.R. [Ecole Royale Militaire/Koninklijke Militaire School, Laboratory for Plasma Physics, Euratom-Belgian State Association, Brussels, Belgium, Partner in the Trilateral Euregio Cluster (Belgium)

2004-07-01

The self-organized criticality (SOC) behavior of the edge plasma transport has been investigated using the fluctuation data measured in the plasma edge and the scrape-off layer of TEXTOR tokamak before and during the edge electrode biasing experiments. In the 'non-shear' discharge phase before biasing, both the potential and density fluctuations clearly exhibit some of the characteristics associated with SOC: (1) existence of f{sup -1} power-law dependence in the frequency spectrum, (2) slowly decaying long tails in the autocorrelation function, (3) values of Hurst parameters larger than 0.5 at all the detected radial locations, (4) non-Gaussian probability density function of fluctuations and (5) radial propagation of avalanche-like events in the edge plasma area. During the biasing phase, with the generation of an edge radial electric field E{sub r} and hence a sheared E{sub r} x B flow, the local turbulence is found to be well de-correlated by the E{sub r} x B velocity shear, consistent with theoretical predictions. Nevertheless, it is concomitantly found that the Hurst parameters are substantially enhanced in the negative flow shear region and in the scrape-off layer as well, which is contrary to theoretical expectation. Implication of these observations to our understanding of plasma transport mechanisms is discussed. (authors)

Flux formulation of DFT on group manifolds and generalized Scherk-Schwarz compactifications

Energy Technology Data Exchange (ETDEWEB)

Bosque, Pascal du [Max-Planck-Institut für Physik,Föhringer Ring 6, 80805 München (Germany); Arnold-Sommerfeld-Center für Theoretische Physik,Fakultät für Physik, Ludwig-Maximilians-Universität München,Theresienstraße 37, 80333 München (Germany); Hassler, Falk [University of North Carolina, Department of Physics and Astronomy,Phillips Hall, CB #3255, 120 E. Cameron Ave., Chapel Hill, NC 27599-3255 (United States); City University of New York, The Graduate Center,365 Fifth Avenue, New York, NY 10016 (United States); Columbia University, Department of Physics,Pupin Hall, 550 West 120th St., New York, NY 10027 (United States); Lüst, Dieter [Max-Planck-Institut für Physik,Föhringer Ring 6, 80805 München (Germany); Arnold-Sommerfeld-Center für Theoretische Physik,Fakultät für Physik, Ludwig-Maximilians-Universität München,Theresienstraße 37, 80333 München (Germany)

2016-02-04

A flux formulation of Double Field Theory on group manifold is derived and applied to study generalized Scherk-Schwarz compactifications, which give rise to a bosonic subsector of half-maximal, electrically gauged supergravities. In contrast to the flux formulation of original DFT, the covariant fluxes split into a fluctuation and a background part. The latter is connected to a 2D-dimensional, pseudo Riemannian manifold, which is isomorphic to a Lie group embedded into O(D,D). All fields and parameters of generalized diffeomorphisms are supported on this manifold, whose metric is spanned by the background vielbein E{sub A}{sup I}∈ GL(2D). This vielbein takes the role of the twist in conventional generalized Scherk-Schwarz compactifications. By doing so, it solves the long standing problem of constructing an appropriate twist for each solution of the embedding tensor. Using the geometric structure, absent in original DFT, E{sub A}{sup I} is identified with the left invariant Maurer-Cartan form on the group manifold, in the same way as it is done in geometric Scherk-Schwarz reductions. We show in detail how the Maurer-Cartan form for semisimple and solvable Lie groups is constructed starting from the Lie algebra. For all compact embeddings in O(3,3), we calculate E{sub A}{sup I}.

Micro-Raman investigations of InN-GaN core-shell nanowires on Si (111) substrate

Energy Technology Data Exchange (ETDEWEB)

Sangeetha, P.; Ramakrishnan, V. [Department of Laser Studies, School of Physics, Madurai Kamaraj University, Madurai-625 021 (India); Jeganathan, K. [Centre for Nanoscience and Nanotechnology, School of Physics, Bharathidasan University, Tiruchirappalli-620 024 (India)

2013-06-15

The electron-phonon interactions in InN-GaN core-shell nanowires grown by plasma assisted- molecular beam epitaxy (MBE) on Si (111) substrate have been analysed using micro-Raman spectroscopic technique with the excitation wavelength of 633, 488 and 325 nm. The Raman scattering at 633 nm reveals the characteristic E{sub 2} (high) and A{sub 1} (LO) phonon mode of InN core at 490 and 590 cm{sup -1} respectively and E{sub 2} (high) phonon mode of GaN shell at 573 cm{sup -1}. The free carrier concentration of InN core is found to be low in the order {approx} 10{sup 16} cm{sup -3} due to the screening of charge carriers by thin GaN shell. Diameter of InN core evaluated using the spatial correlation model is consistent with the transmission electron microscopic measurement of {approx}15 nm. The phonon-life time of core-shell nanowire structure is estimated to be {approx}0.4 ps. The micro-Raman mapping and its corresponding localised spectra for 325 nm excitation exhibit intense E{sub 2} (high) phonon mode of GaN shell at 573 cm{sup -1} as the decrease of laser interaction length and the signal intensity is quenched at the voids due to high spacing of NWs.

ENDF/B fission product decay data

International Nuclear Information System (INIS)

Rose, P.F.; Burrows, T.W.

1976-08-01

The fission product data have been organized by A-chains in order of ascending A from A = 72 to A = 167. The heading page is followed by more detailed information on the individual members of the chain in order of increasing Z and decreasing metastable state. The detailed information for each member includes the ENDF/B-IV File 1 comments and references if available and applicable to the decay data. Following the comments is a decay scheme of the nuclide tabulating the quantities T/sub 1 / 2 /, Q, branching ratio (BR), (E/sub γ/), (E/sub β/), and (E/sub α/). Uncertainties are given if available in the file. Independent fission yields are given, as well as thermal cross sections and resonance integrals as obtained from ENDF/B-IV. All energies listed in this publication are in keV, and all branching ratios (BR) sum to unity. If there are spectra in the decay data file, the decay scheme is followed by tables of photon, particle, and characteristic radiation. For cases in which the multipolarities could be obtained from the file the tables also contain information on x-rays, conversion electrons, and Auger electrons. Associated with the photon and particle radiation tables are the appropriate average energies per decay for each type of radiation, including neutrino radiation

Optical properties of CuCdTeO thin films sputtered from CdTe-CuO composite targets

Energy Technology Data Exchange (ETDEWEB)

Mendoza-Galván, A., E-mail: amendoza@qro.cinvestav.mx [Cinvestav-IPN, Unidad Querétaro, Libramiento Norponiente 2000, 76230 Querétaro (Mexico); Laboratory of Applied Optics, Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping (Sweden); Arreola-Jardón, G. [Cinvestav-IPN, Unidad Querétaro, Libramiento Norponiente 2000, 76230 Querétaro (Mexico); Karlsson, L.H.; Persson, P.O.Å. [Thin Film Physics Division, Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping (Sweden); Jiménez-Sandoval, S. [Cinvestav-IPN, Unidad Querétaro, Libramiento Norponiente 2000, 76230 Querétaro (Mexico)

2014-11-28

The effective complex dielectric function (ε) of Cu and O containing CdTe thin films is reported in the spectral range of 0.05 to 6 eV. The films were fabricated by rf sputtering from targets comprised by a mixture of CdTe and CuO powders with nominal Cu and O concentrations in the range of 2–10 at.%. Low concentration levels improved the crystalline quality of the films. Spectroscopic ellipsometry and transmittance measurements were used to determine ε. The critical point energies E{sub 1}, E{sub 1} + Δ{sub 1}, and E{sub 2} of CdTe are red-shifted with the incorporation of Cu and O. Also, an absorption band is developed in the infrared range which is associated with a mixture of CdTe and low resistivity phases Cu{sub 2−x}Te according to an effective medium analysis. The elemental distribution of the films was mapped by energy dispersive X-ray spectroscopy using scanning transmission electron microscopy. - Highlights: • Incorporation of 2 to 10 at.% of Cu and O atoms in CdTe films • Improved crystalline quality with 2 and 3 at.% of Cu and O • Complex dielectric function of Cu and O containing CdTe thin films • Effective medium modeling of below band-gap absorption.

SU-G-JeP1-08: Dual Modality Verification for Respiratory Gating Using New Real- Time Tumor Tracking Radiotherapy System

Energy Technology Data Exchange (ETDEWEB)

Shiinoki, T; Hanazawa, H; Shibuya, K [Yamaguchi University, Ube, Yamaguchi (Japan); Kawamura, S; Koike, M; Yuasa, Y; Uehara, T; Fujimoto, K [Yamaguchi University Hospital, Ube, Yamaguchi (Japan)

2016-06-15

Purpose: The respirato ry gating system combined the TrueBeam and a new real-time tumor-tracking radiotherapy system (RTRT) was installed. The RTRT system consists of two x-ray tubes and color image intensifiers. Using fluoroscopic images, the fiducial marker which was implanted near the tumor was tracked and was used as the internal surrogate for respiratory gating. The purposes of this study was to develop the verification technique of the respiratory gating with the new RTRT using cine electronic portal image device images (EPIDs) of TrueBeam and log files of the RTRT. Methods: A patient who underwent respiratory gated SBRT of the lung using the RTRT were enrolled in this study. For a patient, the log files of three-dimensional coordinate of fiducial marker used as an internal surrogate were acquired using the RTRT. Simultaneously, the cine EPIDs were acquired during respiratory gated radiotherapy. The data acquisition was performed for one field at five sessions during the course of SBRT. The residual motion errors were calculated using the log files (E{sub log}). The fiducial marker used as an internal surrogate into the cine EPIDs was automatically extracted by in-house software based on the template-matching algorithm. The differences between the the marker positions of cine EPIDs and digitally reconstructed radiograph were calculated (E{sub EPID}). Results: Marker detection on EPID using in-house software was influenced by low image contrast. For one field during the course of SBRT, the respiratory gating using the RTRT showed the mean ± S.D. of 95{sup th} percentile E{sub EPID} were 1.3 ± 0.3 mm,1.1 ± 0.5 mm,and those of E{sub log} were 1.5 ± 0.2 mm, 1.1 ± 0.2 mm in LR and SI directions, respectively. Conclusion: We have developed the verification method of respiratory gating combined TrueBeam and new real-time tumor-tracking radiotherapy system using EPIDs and log files.

Dijets in photoproduction and soft multiparton interactions at HERA

Energy Technology Data Exchange (ETDEWEB)

Naumann, S.

2007-07-15

Dijet events in photoproduction at HERA have been studied using data collected with the ZEUS detector in the period 1998-2000 that correspond to an integrated luminosity of 81.7 pb{sup -1}. The events have been selected in a kinematic region defined by restricting the virtuality of the incoming photon, Q{sup 2}, to Q{sup 2}<1 GeV{sup 2} and its inelasticity, y, to 0.2E{sub T,1}>14 GeV and E{sub T,2}>11 GeV in each event. Cross sections measured for this inclusive dijet sample have been compared to results obtained in data from the 1996-1997 period. Another sample of dijet events has been obtained using the transverse-energy requirements E{sub T,1}>10 GeV and E{sub T,2}>8 GeV, demanding additionally that the two jets are roughly back-to-back in the azimuthal plane and have almost equal transverse energies and that no third hard jet is found in the event. All results have been compared to leading-order Monte Carlo predictions. The transverse energy in the region between the jets shows a large sensitivity to multiparton interactions, allowing parameters of the corresponding models to be tested. The measurement suggests that multiparton interactions are needed to describe the data. The analysis presented here contains the most comprehensive study of soft multiparton interactions at ZEUS to date. (orig.)

Pregnenolone co-treatment partially restores steroidogenesis, but does not prevent growth inhibition and increased atresia in mouse ovarian antral follicles treated with mono-hydroxy methoxychlor

Energy Technology Data Exchange (ETDEWEB)

Craig, Zelieann R., E-mail: zelieann@illinois.edu; Hannon, Patrick R., E-mail: phannon2@illinois.edu; Flaws, Jodi A., E-mail: jflaws@illinois.edu

2013-11-01

Mono-hydroxy methoxychlor (mono-OH MXC) is a metabolite of the pesticide, methoxychlor (MXC). Although MXC is known to decrease antral follicle numbers, and increase follicle death in rodents, not much is known about the ovarian effects of mono-OH MXC. Previous studies indicate that mono-OH MXC inhibits mouse antral follicle growth, increases follicle death, and inhibits steroidogenesis in vitro. Further, previous studies indicate that CYP11A1 expression and production of progesterone (P{sub 4}) may be the early targets of mono-OH MXC in the steroidogenic pathway. Thus, this study tested whether supplementing pregnenolone, the precursor of progesterone and the substrate for HSD3B, would prevent decreased steroidogenesis, inhibited follicle growth, and increased follicle atresia in mono-OH MXC-treated follicles. Mouse antral follicles were exposed to vehicle (dimethylsulfoxide), mono-OH MXC (10 μg/mL), pregnenolone (1 μg/mL), or mono-OH MXC and pregnenolone together for 96 h. Levels of P{sub 4}, androstenedione (A), testosterone (T), estrone (E{sub 1}), and 17β-estradiol (E{sub 2}) in media were determined, and follicles were processed for histological evaluation of atresia. Pregnenolone treatment alone stimulated production of all steroid hormones except E{sub 2}. Mono-OH MXC-treated follicles had decreased sex steroids, but when given pregnenolone, produced levels of P{sub 4}, A, T, and E{sub 1} that were comparable to those in vehicle-treated follicles. Pregnenolone treatment did not prevent growth inhibition and increased atresia in mono-OH MXC-treated follicles. Collectively, these data support the idea that the most upstream effect of mono-OH MXC on steroidogenesis is by reducing the availability of pregnenolone, and that adding pregnenolone may not be sufficient to prevent inhibited follicle growth and survival. - Highlights: • Mono-OH MXC inhibited antral follicle steroidogenesis, growth, and survival. • Pregnenolone partially restored steroidogenesis

Stand-Level Gas-Exchange Responses to Seasonal Drought in Very Young Versus Old Douglas-fir Forests of the Pacific Northwest, USA

Energy Technology Data Exchange (ETDEWEB)

Wharton, S; Schroeder, M; Bible, K; Falk, M; Paw U, K T

2009-02-23

This study examines how stand age affects ecosystem mass and energy exchange response to seasonal drought in three adjacent Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) forests. The sites include two early seral stands (ES) (0-15 years old) and an old-growth (OG) ({approx} 450-500) forest in the Wind River Experiment Forest, Washington, USA. We use eddy covariance flux measurements of carbon dioxide (F{sub NEE}), latent energy ({lambda}E) and sensible heat (H) to derive evapotranspiration rate (E{sub T}), bowen ratio ({beta}), water use efficiency (WUE), canopy conductance (G{sub c}), the Priestley-Taylor coefficient ({alpha}) and a canopy decoupling factor ({Omega}). The canopy and bulk parameters are examined to see how ecophysiological responses to water stress, including changes in available soil water ({theta}{sub r}) and vapor pressure deficit ({delta}e) differ among the two forest successional-stages. Despite very different rainfall patterns in 2006 and 2007, we observed distinct successional-stage relationships between E{sub T}, {alpha}, and G{sub c} to {delta}e and {theta}{sub r} during both years. The largest stand differences were (1) higher morning G{sub c} (> 10 mm s{sup -1}) at the OG forest coinciding with higher CO{sub 2} uptake (F{sub NEE} = -9 to -6 {micro}mol m{sup -2} s{sup -1}) but a strong negative response in G{sub c} to moderate {delta}e later in the day and a subsequent reduction in E{sub T}, and (2) higher E{sub T} at the ES stands because midday canopy conductance did not decrease until very low water availability levels (<30%) were reached at the end of the summer. Our results suggest that early seral stands are more likely than mature forests to experience declines in production if the summer drought becomes longer or intensifies because water conserving ecophysiological responses were only observed at the very end of the seasonal drought period in the youngest stands.

Physical properties of chemically deposited Bi{sub 2}S{sub 3} thin films using two post-deposition treatments

Energy Technology Data Exchange (ETDEWEB)

Moreno-García, H., E-mail: hamog@ier.unam.mx [Instituto de Ciencias Físicas, Laboratorio de espectroscopia, Universidad Nacional Autónoma de México, Apartado Postal 48-3, C.P. 62210 Cuernavaca, Morelos (Mexico); Messina, S. [Universidad Autónoma de Nayarit, Ciudad de la Cultura “Amado Nervo” S/N, C.P. 63155 Tepic, Nayarit (Mexico); Calixto-Rodriguez, M. [Universidad Tecnológica Emiliano Zapata del Estado de Morelos, Av. Universidad Tecnológica No. 1, C.P. 62760 Emiliano Zapata, Morelos (Mexico); Martínez, H. [Instituto de Ciencias Físicas, Laboratorio de espectroscopia, Universidad Nacional Autónoma de México, Apartado Postal 48-3, C.P. 62210 Cuernavaca, Morelos (Mexico)

2014-08-30

Highlights: • The post-deposition treatment by Ar plasma is a viable alternative to enhance the optical, electrical, morphological and structural properties of Bi{sub 2}S{sub 3} semiconductor thin films. • The plasma treatment avoids the loss in thickness of the chemically deposited Bi{sub 2}S{sub 3} thin films. • The E{sub g} values were 1.60 eV for the thermally annealed samples and 1.56 eV for the Ar plasma treated samples. • The highest value obtained for the electrical conductivity was 7.7 × 10{sup −2} (Ω cm){sup −1} in plasma treated samples. - Abstract: As-deposited bismuth sulfide (Bi{sub 2}S{sub 3}) thin films prepared by chemical bath deposition technique were treated with thermal annealed in air atmosphere and argon AC plasma. The as-deposited, thermally annealing and plasma treatment Bi{sub 2}S{sub 3} thin films have been characterized by X-ray diffraction (XRD) analysis, atomic force microscopy analysis (AFM), transmission, specular reflectance and electrical measurements. The structural, morphological, optical and electrical properties of the films are compared. The XRD analysis showed that both post-deposition treatments, transform the thin films from amorphous to a crystalline phase. The atomic force microscopy (AFM) measurement showed a reduction of roughness for the films treated in plasma. The energy band gap value of the as-prepared film was E{sub g} = 1.61 eV, while for the film thermally annealed was E{sub g} = 1.60 eV and E{sub g} = 1.56 eV for film treated with Plasma. The electrical conductivity under illumination of the as-prepared films was 3.6 × 10{sup −5} (Ω cm){sup −1}, whereas the conductivity value for the thermally annealed films was 2.0 × 10{sup −3} (Ω cm){sup −1} and for the plasma treated films the electrical conductivity increases up to 7.7 × 10{sup −2} (Ω cm){sup −1}.

Visible light absorbance enhanced by nitrogen embedded in the surface layer of Mn-doped sodium niobate crystals, detected by ultra violet - visible spectroscopy, x-ray photoelectron spectroscopy, and electric conductivity tests

Energy Technology Data Exchange (ETDEWEB)

Molak, A., E-mail: andrzej.molak@us.edu.pl; Pilch, M. [Institute of Physics, University of Silesia, ul. Uniwersytecka 4, 40-007 Katowice (Poland)

2016-05-28

Sodium niobate crystals doped with manganese ions, Na(NbMn)O{sub 3}, were annealed in a nitrogen N{sub 2} flow at 600, 670, and 930 K. It was verified that simultaneous doping with Mn ions and annealing in nitrogen enhanced the photocatalytic features of sodium niobate. The transmission in the ultraviolet-visible range was measured at room temperature. The absorbance edge is in the range from 3.4 to 2.3 eV. The optical band gap E{sub gap} = 1.2–1.3 eV was evaluated using the Tauc relation. Crystals annealed at 670 K and 930 K exhibited an additional shift of the absorption edge of ∼20–40 nm toward longer wavelengths. The optical energy gap narrowed as a result of the superimposed effect of Mn and N co-doping. The x-ray photoelectron spectroscopy test showed that N ions incorporated into the surface layer. The valence band consisted of O 2p states hybridized with Nb 4d, Mn 3d, and N 2s states. The disorder detected in the surroundings of Nb and O ions decreased due to annealing. The binding energy of oxygen ions situated within the surface layer was E{sub B} ≈ 531 eV. The other contributions were assigned to molecular contamination. The contribution centered at 535.5 eV vanished after annealing at 600 K and 670 K. The contribution centered at 534 eV vanished after annealing at 930 K. The N{sub 2} annealing partly removed carbonates from the surfaces of the samples. In the 480–950 K range, the electric conductivity activation energy, E{sub a} = 0.7–1.2 eV, was comparable with the optical E{sub gap}. The electric permittivity showed dispersion in the 0.1–800 kHz range that corresponds to the occurrence of defects.

Primary transitions between the yrast superdeformed band and low-lying normal deformed states in {sup 194}Pb

Energy Technology Data Exchange (ETDEWEB)

Hauschild, K.; Bernstein, L.A.; Becker, J.A. [Lawrence Livermore National Lab., CA (United States)] [and others

1996-12-31

The observation of one-step `primary` gamma-ray transitions directly linking the superdeformed (SD) states to the normal deformed (ND) low-lying states of known excitation energies (E{sub x}), spins and parities (J{sup {pi}}) is crucial to determining the E{sub x} and J{sup {pi}} of the SD states. With this knowledge one can begin to address some of the outstanding problems associated with SD nuclei, such as the identical band issue, and one can also place more stringent restrictions on theoretical calculations which predict SD states and their properties. Brinkman, et al., used the early implementation of the GAMMASPHERE spectrometer array (32 detectors) and proposed a single, candidate {gamma} ray linking the {sup 194}Pb yrast SD band to the low-lying ND states in {sup 194}Pb. Using 55 detectors in the GAMMASPHERE array Khoo, et al., observed multiple links between the yrast SD band in {sup 194}Hg and the low-lying level scheme and conclusively determined E{sub x} and J of the yrast SD states. Here the authors report on an experiment in which Gammasphere with 88 detectors was used and the E{sub x} and J{sup {pi}} values of the yrast SD states in {sup 194}Pb were uniquely determined. Twelve one-step linking transitions between the yrast SD band and low-lying states in {sup 194}Pb have been identified, including the transition proposed by Brinkman. These transitions have been placed in the level scheme of {sup 194}Pb using coincidence relationships and agreements between the energies of the primary transitions and the energy differences in level spacings. Furthermore, measurements of angular asymmetries have yielded the multipolarities of the primaries which have allowed J{sup {pi}} assignments of the {sup 194}Pb SD states to be unambiguously determined for the first time without a priori assumptions about the character of SD bands. A study performed in parallel to this work using the EUROGAM-II array reports similar, but somewhat less extensive, results.

Searching for gravitational-wave signals emitted by eccentric compact binaries using a non-eccentric template bank: implications for ground-based detectors

Energy Technology Data Exchange (ETDEWEB)

Cokelaer, T; Pathak, D, E-mail: Thomas.Cokelaer@astro.cf.ac.u, E-mail: Devanka.Pathak@astro.cf.ac.u [School of Physics and Astronomy, Cardiff University, Cardiff CF24 3AA (United Kingdom)

2009-02-21

Most of the inspiralling compact binaries are expected to be circularized by the time their gravitational-wave signals enter the frequency band of ground-based detectors such as LIGO or VIRGO. However, it is not excluded that some of these binaries might still possess a significant eccentricity at a few tens of hertz. Despite this possibility, current search pipelines-based on matched filtering techniques-consider only non-eccentric templates. The effect of such an approximation on the loss of signal-to-noise ratio (SNR) has been investigated by Martel and Poisson (1999 Phys. Rev. D 60 124008) in the context of initial LIGO detector. They ascertained that non-eccentric templates will be successful at detecting eccentric signals. We revisit their work by incorporating current and future ground-based detectors and precisely quantify the exact loss of SNR. In order to be more faithful to an actual search, we maximized the SNR over a template bank, whose minimal match is set to 95%. For initial LIGO detector, we claim that the initial eccentricity does not need to be taken into account in our searches for any system with total mass M element of [2-45]M{sub o-dot} if e{sub 0} approx< 0.05 because the loss of SNR (about 5%) is consistent with the discreteness of the template bank. Similarly, this statement is also true for systems with M element of [6-35]M{sub o-dot} and e{sub 0} approx< 0.10. However, by neglecting the eccentricity in our searches, significant loss of detection (larger than 10%) may arise as soon as e{sub 0} >= 0.05 for neutron-star binaries. We also provide exhaustive results for VIRGO, Advanced LIGO and Einstein Telescope detectors. It is worth noting that for Einstein Telescope, neutron star binaries with e{sub 0} >= 0.02 lead to a 10% loss of detection.

Resveratrol protects the ovary against chromium-toxicity by enhancing endogenous antioxidant enzymes and inhibiting metabolic clearance of estradiol

Energy Technology Data Exchange (ETDEWEB)

Banu, Sakhila K., E-mail: skbanu@cvm.tamu.edu; Stanley, Jone A.; Sivakumar, Kirthiram K.; Arosh, Joe A.; Burghardt, Robert C.

2016-07-15

Resveratrol (RVT), a polyphenolic component in grapes and red wine, has been known for its cytoprotective actions against several diseases. However, beneficial effects of RVT against early exposure to endocrine disrupting chemicals (EDCs) have not been understood. EDCs are linked to several ovarian diseases such as premature ovarian failure, polycystic ovary syndrome, early menopause and infertility in women. Hexavalent chromium (CrVI) is a heavy metal EDC, and widely used in > 50 industries. Environmental contamination with CrVI in the US is rapidly increasing, predisposing the human to several illnesses including cancers and still birth. Our lab has been involved in determining the molecular mechanism of CrVI-induced female infertility and intervention strategies to mitigate CrVI effects. Lactating mother rats were exposed to CrVI (50 ppm potassium dichromate) from postpartum days 1–21 through drinking water with or without RVT (10 mg/kg body wt., through oral gavage daily). During this time, F1 females received respective treatments through mother's milk. On postnatal day (PND) 25, blood and the ovary, kidney and liver were collected from the F1 females for analyses. CrVI increased atresia of follicles by increasing cytochrome C and cleaved caspase-3; decreasing antiapoptotic proteins; decreasing estradiol (E{sub 2}) biosynthesis and enhancing metabolic clearance of E{sub 2}, increasing oxidative stress and decreasing endogenous antioxidants. RVT mitigated the effects of CrVI by upregulating cell survival proteins and AOXs; and restored E{sub 2} levels by inhibiting hydroxylation, glucuronidation and sulphation of E{sub 2}. This is the first study to report the protective effects of RVT against any toxicant in the ovary. - Highlights: • Resveratrol (RVT) protects the ovary against CrVI-toxicity. • RVT mitigated CrVI-induced apoptosis and follicle atresia. • RVT restored estradiol level against CrVI-toxicity. • RVT inhibited metabolic clearance of

Wavelength dependence of interstellar polarization and ratio of total to selective extinction

International Nuclear Information System (INIS)

Serkowski, K.; Mathewson, D.S.; Ford, V.L.

1975-01-01

Wavelength dependence of interstellar linear polarization has been observed for about 180 stars, mostly southern, in the UBVR spectral regions. A multichannel polarimeter-photometer, in which spectral regions are separated by dichroic filters, was used. Normalized wavelength dependence of interstellar linear polarization p follows closely a single empirical curve p (lambda)/p /sub max/=exp-1.15 ln 2 (lambda/sub max//lambda), where the wavelength lambda/sub max/ at which the maximum interstellar linear polarization p/sub max/ occurs takes values from 0.45 μ to 0.8 μ. Wavelength lambda/sub max/ is well correlated with the ratios of color excesses E/sub V-K//E/sub B-V/, E/sub V-K//E/sub V-R/, and E/sub V-I//E/sub V-R/. These correlations indicate that the ratio R of total to selective interstellar extinction can be found for any individual star from the relationship R = 5.5 lambda/sub max/. Polarimetry seems to be the most practical method of estimating R. A map of distribution of lambda/sub max/ on the sky, based on values for about 350 stars, indicates several well defined regions with lambda/sub max/, and hence R, clearly larger (or smaller) than the median value lambda/sub max/ = π.545 μ, corresponding to R = 3.0. The predominance of larger than average values of lambda/sub max/ among stars nearer than 0.4 kpc and the negative correlation between lambda/sub max/ and E/sub B-V/ are explained by selection effects. There is evidence of negative correlation between lambda/sub max/ and p/sub max//E/sub B-V/ suggested by Kruszewski. The lower limits for color excess of Praesepe, M67, and several globular clusters are set by their linear polarization. The largest known values of interstellar circular polarization, parallel q parallel approximately equal to 0.06 percent, were found in near-infrared for two stars with exceptionally small lambda/sub max/: star No. 12 in association VI Cygni and HD 204827. (U.S.)

High-pitch computed tomography of the lung in pediatric patients. An intraindividual comparison of image quality and radiation dose to conventional 64-MDCT

Energy Technology Data Exchange (ETDEWEB)

Tsiflikas, I.; Thomas, C.; Ketelsen, D.; Claussen, C.D.; Schaefer, J.F. [University Hospital of Tuebingen (Germany). Diagnostic and Interventional Radiology; Seitz, G.; Warmann, S. [University Hospital of Tuebingen (Germany). Pediatric Surgery

2014-06-15

Purpose: The aim of this study was to investigate frequencies of typical artifacts in low-dose pediatric lung examinations using high-pitch computed tomography (HPCT) compared to MDCT, and to estimate the effective radiation dose (E{sub eff}). Materials and Methods: Institutional review board approval for this retrospective study was obtained. 35 patients (17 boys, 18 girls; mean age 112 ± 69 months) were included and underwent MDCT and follow-up scan by HPCT or vice versa (mean follow-up time 87 days), using the same tube voltage and current. The total artifact score (0-8) was defined as the sum of artifacts arising from movement, breathing or pulsation of the heart or pulmonary vessels (0 - no; 1 - moderate; 2 - severe artifacts). E{sub eff} was estimated according to the European Guidelines on Quality Criteria for Multislice Computed Tomography. The Mann-Whitney U test was used to analyze differences between the patient groups. The Spearman's rank correlation coefficient was used for correlation of ordinal variables. Results: The scan time was significantly lower for HPCT compared to MDCT (0.72 ± 0.13 s vs. 3.65 ± 0.81s; p < 0.0001). In 28 of 35 (80 %) HPCT examinations no artifacts were visible, whereas in MDCT artifacts occurred in all examinations. The frequency of pulsation artifacts and breathing artifacts was higher in MDCT compared to HPCT (100% vs. 17% and 31% vs. 6%). The total artifact score significantly correlated with the patient's age in MDCT (r=-0.42; p=0.01), but not in HPCT (r=-0.32; p=0.07). The estimated E{sub eff} was significantly lower in HPCT than in MDCT (1.29±0.31 vs. 1.47±0.37 mSv; p < 0.0001). Conclusion: Our study indicates that the use of HPCT has advantages for pediatric lung imaging with a reduction of breathing and pulsation artifacts. Moreover, the estimated E{sub eff} was lower. In addition, examinations can be performed without sedation or breath-hold without losing image quality. (orig.)

RCNP E398 {sup 16}O,{sup 12}C(p,p’) experiment: Measurement of the γ-ray emission probability from giant resonances in relation to {sup 16}O,{sup 12}C(ν,ν’) reactions

Energy Technology Data Exchange (ETDEWEB)

Ou, I.; Yamada, Y.; Mori, T.; Yano, T.; Sakuda, M. [Department of Physics, Okayama University, Okayama 700-8530 (Japan); Tamii, A.; Suzuki, T.; Yosoi, M.; Aoi, N.; Ideguchi, E.; Hashimoto, T.; Miki, K.; Ito, T.; Iwamoto, C.; Yamamoto, T. [Research Center for Nuclear Physics (RCNP), Osaka University, Ibaraki, Osaka 567-0047 (Japan); Akimune, H. [Department of Physics, Konan University, Okamoto 8-9-1, Higashinada, Kobe 658-8501 (Japan)

2015-05-15

We propose to measure the γ-ray emission probability from excited states above 5 MeV including giant resonance of {sup 16}O and {sup 12}C as a function of excitation energy in 1-MeV step. Here, we measure both the excitation energy (E{sub x}=5-30MeV) at the forward scattering angles (0°-3°) of the {sup 16}O, {sup 12}C (p, p’) reaction using Grand-Raiden Spectrometer and the energy of γ-rays (E{sub γ}) using an array of NaI(Tl) counters. The purpose of the experiment is to provide the basic and important information not only for the γ-ray production from primary neutral-current neutrino-oxygen (-carbon) interactions but also for that from the secondary hadronic (neutron-oxygen and -carbon) interactions.

Microscopic theory of longitudinal sound velocity in charge ordered manganites

Energy Technology Data Exchange (ETDEWEB)

Rout, G C [Condensed Matter Physics Group, PG Department of Applied Physics and Ballistics, FM University, Balasore 756 019 (India); Panda, S, E-mail: gcr@iopb.res.i [Trident Academy of Technology, F2/A, Chandaka Industrial Estate, Bhubaneswar 751 024 (India)

2009-10-14

A microscopic theory of longitudinal sound velocity in a manganite system is reported here. The manganite system is described by a model Hamiltonian consisting of charge density wave (CDW) interaction in the e{sub g} band, an exchange interaction between spins of the itinerant e{sub g} band electrons and the core t{sub 2g} electrons, and the Heisenberg interaction of the core level spins. The magnetization and the CDW order parameters are considered within mean-field approximations. The phonon Green's function was calculated by Zubarev's technique and hence the longitudinal velocity of sound was finally calculated for the manganite system. The results show that the elastic spring involved in the velocity of sound exhibits strong stiffening in the CDW phase with a decrease in temperature as observed in experiments.

Photoproduction of isolated photons, inclusively and with a jet, at HERA

Energy Technology Data Exchange (ETDEWEB)

Abramowicz, H. [Tel Aviv Univ. (Israel). School of Physics; Max-Planck-Institute for Physics, Munich (Germany); Abt, I. [Max-Planck-Institute for Physics, Munich (Germany); Adamczyk, L. [AGH-Univ. of Science and Technology, Krakow (Poland). Faculty of Physics and Applied Computer Science; Collaboration: ZEUS Collaboration; and others

2013-12-15

The photoproduction of isolated photons, both inclusive and together with a jet, has been measured with the ZEUS detector at HERA using an integrated luminosity of 374 pb{sup -1}. Differential cross sections are presented in the isolated-photon transverse-energy and pseudorapidity ranges 6<E{sub T}{sup {gamma}}<15 GeV and -0.7 <{eta}{sup {gamma}}<0.9, and for jet transverse-energy and pseudorapidity ranges 4<E{sub T}{sup jet}<35 GeV and -1.5<{eta}{sup jet}<1.8, for exchanged-photon virtualities Q{sup 2}<1 GeV{sup 2}. Differential cross sections are also presented for inclusive isolated photon production as functions of the transverse energy and pseudorapidity of the photon. Higher-order theoretical calculations are compared to the results.

Beta ray backscattering studies for thickness measurements

Energy Technology Data Exchange (ETDEWEB)

Singh, M; Sharma, K K [Punjabi Univ., Patiala (India). Nuclear Science Labs.

1979-01-01

Back-scattering of beta rays from /sup 204/Tl (Esub(..beta..)max = 740 keV) and /sup 90/Sr-/sup 90/Y (Esub(..beta..)max =550 and 2250 keV) has been studied in an improved reflection geometry, using annular sources, from a number of elemental targets with Z values ranging from 13 to 82. Source to target and target to detector geometry factors are 0.0225 and 0.0282 respectively. Values of saturation back scattering thickness obtained in the two cases are 72 +- 10 and 190 +- 40 mg/cm/sup 2/ respectively. It is observed that the intensity of back scattered radiation varies linearly with thickness upto a value of 12 +- 2 mg/cm/sup 2/ in /sup 204/Tl and 17 +- 3 mg/cm/sup 2/ in /sup 90/Sr-/sup 90/Y.

High spin levels in 62Zn, 64Zn, 66Zn, and 68Zn

International Nuclear Information System (INIS)

Bruandet, J.-F.

1976-01-01

Investigation by in-beam gamma spectroscopy of high-spin states in the even zinc isotopes has been made using the Ni(α,2nγ)Zn reactions at Esub(α) approximately equal to 30MeV for 62 Zn, 64 Zn and 66 Zn, and the 65 Cu(α,pγ) reaction at Esub(α) approximately equal to 18MeV for 68 Zn. The high-spin states feeding by varying the incident particles: p, 3 He,α, 12 C is discussed. It is pointed out that the gsub(9/2) orbital plays an important role in the structure of the high-spin states. The variation of the inertia momentum throughout the yrast line shows a backbending behavior and a shape transition associated to the occurence, for J>6, of rotational states is speculated [fr

Correlation of the concentration of the carbon-associated radiation damage levels with the total carbon concentration in silicon

Energy Technology Data Exchange (ETDEWEB)

Ferenczi, G.; Londos, C.A.; Pavelka, T.; Somogyi, M.; Mertens, A.

1988-01-01

The dominant carbon-related radiation damage center in silicon was studied in detail by deep level transient spectroscopy. Samples with different carbon and oxygen content were implanted with gradually increasing proton fluence. Two energetically closely spaced levels were revealed and tentative identities were assigned. One at E/sub T/+E/sub V/ = 0.344 eV (sigma/sub p/ = 1.1 x 10/sup -16/ cm/sup 2/) is assigned as the C+O/sub i/ complex, and that at E/sub T/+E/sub V/ = 0.370 eV (sigma/sub p/ = 8 x 10/sup -18/ cm/sup 2/) is assigned as the C/sub s/-Si/sub i/-C/sub s/ complex. It was shown that the concentration of these defects is correlated to the total concentration of carbon in the crystal.

Deep levels in SiC:V by high temperature transport measurements

Energy Technology Data Exchange (ETDEWEB)

Mitchel, W.C.; Perrin, R.; Goldstein, J.; Roth, M.; Ahoujja, M.; Smith, S.R.; Solomon, J.S.; Landis, G.; Jenny, J. [Air Force Materials Lab., Wright-Patterson AFB, OH (United States). Research and Technology Div.; Evwaraye, A.O. [Univ. of Dayton, Dayton, OH (United States); Hobgood, H.McD.; Augustine, G.; Balakrishna, V. [Northrop Grumman Corp., Science and Technology Center, Pittsburgh, PA (United States)

1998-06-01

Vanadium doped 6H and 4H SiC have been studied with high temperature Hall effect and resistivity, optical absorption and SIMS. The 6H samples were found to exhibit three thermal activation energies, 0.35 eV, 0.7 eV and near mid-gap. The 0.3 eV level is due to thermal ionization of residual uncompensated boron. We attribute the mid-gap level to thermal ionization of the vanadium donor level. The 0.7 eV activation is believed to be due to transfer of electrons from the ionized vanadium acceptor levels to the conduction band. These results suggest that the vanadium donor and acceptor levels are located at E{sub c}-1.42 eV and E{sub V} + 2.4 eV respectively. (orig.) 7 refs.

The {sup 14}N(p, {gamma}){sup 15}O reaction studied at low and high beam energy

Energy Technology Data Exchange (ETDEWEB)

Marta, Michele

2012-07-01

The Bethe-Weizsaecker cycle consists of a set of nuclear reactions that convert hydrogen into helium and release energy in the stars. It determines the luminosity of low-metal stars at their turn-off from the main-sequence in the Hertzsprung-Russel diagram, so its rate enters the calculation of the globular clusters' age, an independent lower limit on the age of the universe. The cycle contributes less than 1% to our Sun's luminosity, but it produces neutrinos that can in principle be measured on Earth in underground experiments and bring direct information of the physical conditions in the solar core, provided that the nuclear reaction rate is known with sufficient precision. The {sup 14}N(p,{gamma}){sup 15}O reaction is the slowest reaction of the Bethe-Weizsaecker cycle and establishes its rate. Its cross section is the sum of the contributions by capture to different excited levels and to the ground state in {sup 15}O. Recent experiments studied the region of the resonance at E{sub p} = 278 keV. Only one modern data set from an experiment performed in 1987 is available for the high-energy domain. Both energy ranges are needed to constrain the fit of the excitation function in the R-matrix framework and to obtain a reliable extrapolated S-factor at the very low astrophysical energies. The present research work studied the {sup 14}N(p,{gamma}){sup 15}O reaction in the LUNA (Laboratory for Underground Nuclear Astrophysics) underground facility at three proton energies 0.36, 0.38, 0.40MeV, and in Dresden in the energy range E{sub p} = 0.6 - 2MeV. In both cases, an intense proton beam was sent on solid titanium nitride sputtered targets, and the prompt photons emitted from the reaction were detected with germanium detectors. At LUNA, a composite germanium detector was used. This enabled a measurement with dramatically reduced summing corrections with respect to previous studies. The cross sections for capture to the ground state and to the excited states

Magnetite-graphene for the direct electrochemistry of hemoglobin and its biosensing application

Energy Technology Data Exchange (ETDEWEB)

He Yaping; Sheng Qinglin [Institute of Analytical Science/Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi' an, Shaanxi 710069 (China); Zheng Jianbin, E-mail: zhengjb@nwu.edu.c [Institute of Analytical Science/Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi' an, Shaanxi 710069 (China); Wang Minzhi [Institute of Analytical Science/Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry, Northwest University, Xi' an, Shaanxi 710069 (China); Liu Bin [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry (Ministry of Education), Northwest University, Xi' an, Shaanxi 710069 (China); Department of Chemistry, Xianyang Normal University, Xianyang, Shaanxi 712000 (China)

2011-02-01

Magnetite-graphene (Fe{sub 3}O{sub 4}-GE) was prepared via a simple effective chemical precipitation method, followed by the chemical reduction with hydrazine. Fe{sub 3}O{sub 4}-GE was characterized by Raman spectroscopy, transmission electron microscope, X-ray powder diffraction and electrochemical methods. A hydrogen peroxide (H{sub 2}O{sub 2}) biosensor was structured by immobilizing hemoglobin (Hb) into Fe{sub 3}O{sub 4}-GE for the first time. UV-vis and Fourier transform infrared spectra were employed to characterize Hb retained original structure in the resulting Hb-Fe{sub 3}O{sub 4}-GE membrane. Electrochemical investigation of the biosensor showed a pair of well-defined, quasi-reversible redox peaks with E{sub pa} = -0.285 V and E{sub pc} = -0.363 V (vs. SCE) in phosphate buffer solution (0.1 mol/L, pH 7.0) at the scan rate of 100 mV/s. The Hb-Fe{sub 3}O{sub 4}-GE showed a better synergistic electrochemical effect for the reduced process of H{sub 2}O{sub 2}. The biosensor displayed a fast response time (<3 s) and broad linear response to H{sub 2}O{sub 2} in the range from 1.50 to 585 {mu}mol/L with a relatively low detection limit of 0.5 {mu}mol/L (S/N = 3). Moreover, the biosensor could be applied in practical analysis and exhibit good reproducibility and long-term stability.

Effect of FEL induced ionization on X-ray reflectivity of multilayers

Energy Technology Data Exchange (ETDEWEB)

Ksenzov, Dmitriy; Grigorian, Souren; Pietsch, Ullrich [University of Siegen (Germany)

2009-07-01

The VUV-FEL in Hamburg (FLASH) emits short-pulse radiation with wavelengths from 6 to 30 nm and a pulse length of 10-50 fs. The FLASH wavelength allows x-ray diffraction experiments at periodical multilayer's structures acting as 1D crystal. The probe of depth selective interaction of the high-intense x-ray short pulse with these objects can be used to obtain information about possible electronic excitation and various recombination processes inside multilayers. As known from recent experiments at FLASH, the later ones are most likely using highly intense FEL radiation. The ML reflectivity is analyzed for case of that the optical parameters are changing as function of the depth of the penetrating incident pulse into the multilayer. The response is studied for the model system La/B{sub 4}C using two experimental conditions both at fixed incidence angle: 1) the energy of the incident pulses, E, coincides with the energy of the 1st order multilayer Bragg peak, E{sub B}, of the reflection curve, and 2) the energy of incident pulse differs by a small dE from E{sub B}. The ML response to a given sub-pulse differs for both conditions. However, there is a clear fingerprint of ionization for both conditions for the case that E is close to the K-absorption edge of B-atoms. Our results support respective efforts to measure the optical parameters of solids under high-intense FEL radiation.

The accuracy of heavy ion optical model calculations

International Nuclear Information System (INIS)

Kozik, T.

1980-01-01

There is investigated in detail the sources and magnitude of numerical errors in heavy ion optical model calculations. It is shown on example of 20 Ne + 24 Mg scattering at Esub(LAB)=100 MeV. (author)

Optical anisotropy of quasi-1D rare-earth silicide nanostructures on Si(001)

Energy Technology Data Exchange (ETDEWEB)

Chandola, S., E-mail: sandhya.chandola@isas.de [Leibniz-Institut für Analytische Wissenschaften – ISAS – e.V., Schwarzschildstraße 8, 12489 Berlin (Germany); Speiser, E.; Esser, N. [Leibniz-Institut für Analytische Wissenschaften – ISAS – e.V., Schwarzschildstraße 8, 12489 Berlin (Germany); Appelfeller, S.; Franz, M.; Dähne, M. [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin (Germany)

2017-03-31

Highlights: • Reflectance anisotropy spectroscopy (RAS) is capable of distinguishing optically between the semiconducting wetting layer and the metallic nanowires of rare earth (Tb and Dy) silicide nanostructures grown on vicinal Si(001). • The spectra of the wetting layer show a distinctive line shape with a large peak appearing at 3.8 eV, which is assigned to the formation of 2 × 3 and 2 × 4-like subunits of the 2 × 7 reconstruction. The spectra of the metallic nanowires show peaks at the E{sub 1} and E{sub 2} transitions of bulk Si which is assigned to strong substrate strain induced by the nanowires. • The optical anisotropy of the Tb nanowires is larger than for the Dy nanowires, which is related to the preferential formation of more strained bundles as well as larger areas of clean Si surfaces in the case of Tb. • RAS is shown to be a powerful addition to surface science techniques for studying the formation of rare-earth silicide nanostructures. Its surface sensitivity and rapidity of response make it an ideal complement to the slower but higher resolution of scanning probes of STM and AFM. - Abstract: Rare earth metals are known to interact strongly with Si(001) surfaces to form different types of silicide nanostructures. Using STM to structurally characterize Dy and Tb silicide nanostructures on vicinal Si(001), it will be shown that reflectance anisotropy spectroscopy (RAS) can be used as an optical fingerprint technique to clearly distinguish between the formation of a semiconducting two-dimensional wetting layer and the metallic one-dimensional nanowires. Moreover, the distinctive spectral features can be related to structural units of the nanostructures. RAS spectra of Tb and Dy nanostructures are found to show similar features.

The crystal structure and electrical properties of K{sub 2}NiF{sub 4}-type (Ca{sub 2−x}Sm{sub x})MnO{sub 4}

Energy Technology Data Exchange (ETDEWEB)

Taguchi, Hideki, E-mail: htaguchi@cc.okayama-u.ac.jp [The Graduate School of Natural Science and Technology (Science), Okayama University, 3-1-1 Tsushima-Naka, Kita-Ku, Okayama 700-8530 (Japan); Kido, Hiroyasu [Osaka Municipal Technical Research Institute, 1-6-50 Morinomiya, Jyoto-Ku, Osaka 536-8553 (Japan); Kato, Masaki; Hirota, Ken [Department of Molecular Chemistry and Biochemistry, Faculty of Science and Engineering, Doshisha University, Kyo-Tanabe 610-0321 (Japan)

2015-04-15

Graphical abstract: The relationship between log ρ of K{sub 2}NiF{sub 4}-type (Ca{sub 2−x}Sm{sub x})MnO{sub 4} and 1000/T. - Highlights: • K{sub 2}NiF{sub 4}-type (Ca{sub 2−x}Sm{sub x})MnO{sub 4} was synthesized using a polymerized complex route. • The semiconductive samples had minimum values of ρ and E{sub a} at x = 0.1. • The log ρ–1/T curve of x = 0.3 consisted of two different lines at 315 K. • The 1/χ − T curve of x = 0.3 had a peak at 325 K. • These results indicated the presence of a charge-ordering transition at x = 0.3. - Abstract: K{sub 2}NiF{sub 4}-type (Ca{sub 2−x}Sm{sub x})MnO{sub 4} (0.02 ≤ x ≤ 0.3) was synthesized using a polymerized complex route. The crystal structure changed from tetragonal to orthorhombic at x = 0.3. A variation in the lattice parameters was explained by the Mn–O(2) distance, the Mn−O(2)−Mn angle, and the (Ca,Sm)–(Ca,Sm) distance. The samples were n-type semiconductors, and the minimum values of electrical resistivity (ρ) and an energy gap (E{sub g}) at x = 0.1 were accounted by electron transfer through an Mn−O(2)−Mn path and overlap between the Mnt{sub 2g} and Op{sub π} orbitals. In the sample (x = 0.3), the log ρ–1000/T curve consisted of two different lines that intersected at ca. 325 K, and a peak was observed at ca. 315 K in the magnetic susceptibility–temperature curve. These results indicated the presence of a charge-ordering (CO) transition at 315–325 K.

Effects of postoperative adjuvant chemotherapy and radiotherapy on ovarian function in women undergoing treatment for soft tissue sarcoma

Energy Technology Data Exchange (ETDEWEB)

Shamberger, R.C. (National Inst. of Health, Bethesda, MD); Sherins, R.J.; Ziegler, J.L.; Glatstein, E.; Rosenberg, S.A.

1981-12-01

Ovarian function was evaluated in 11 women 16 to 43 years of age at treatment who received doxorubicin, cyclophosphamide, and high doses of methotrexate with or without radiotherapy in adjuvant therapy of soft tissue sarcoma. Five women (16-33 yr old) who received chemotherapy alone or combined with radiotherapy only at sites distant from the ovaries (chest wall, thigh, and leg) had minimal menstrual irregularities or temporary cessation of menses during therapy; cyclic menses returned promptly after therapy. Gonadotropin levels (expressed as means +/- SD) (follicle-stimulating hormone (FSH), 10 +/- 15 mlU/ml; luteinizing hormone (LH), 10 +/- 4 mlU/ml) and 17 ..beta..-estradiol (E/sub 2/) levels (means +/- SD, 208 +/- 147 pg/ml) were normal. By contrast, 4 older women (ages 36-43 yr) who received similar treatment developd persistent amenorrhea with postmenopausal levels of gonadotropin (FSH, 109 +/- 29 mlU/ml; LH, 72 +/- 19 mlU/ml) and E/sub 2/ (19 +/- 8 pg/ml). Two additional women (ages 21 and 39 yr) who received radiation (7000 rad) to the pelvis plus chemotherapy developed prompt cessation of menses and became functional castrates (FSH, 77 and 80mlU/ml; LH, 40 and 58 mlU/ml; E/sub 2/, 10 and 19 pg/ml). However, this result would be expected from the radiation dose alone. The data demonstrated that ovarian dysfunction may follow the use of doxorubicin, cyclophosphamide, and high doses of methotrexate and that the injury is age related.

Study of structural and optical properties of Cd{sub 1-x}Zn{sub x}Se thin films

Energy Technology Data Exchange (ETDEWEB)

Wahab, L.A., E-mail: aly_lo2003@yahoo.com [National Center for Radiation Research and Technology, Nasr City, Cairo (Egypt); Zayed, H.A. [University Collage of Women for Art, Science and Education, Ain Shams University, Cairo (Egypt); El-Galil, A.A. Abd [National Center for Radiation Research and Technology, Nasr City, Cairo (Egypt)

2012-06-01

Cd{sub 1-x}Zn{sub x}Se (x = 0, 0.5 and 1) thin films have been deposited onto glass substrates using thermal evaporation technique. The lattice constants, grain size, microstrain and dislocation density were studied by using X-ray diffraction. In addition the optical constants were calculated in the wavelength range 400-2500 nm. Transmittance and reflectance were used to calculate the absorption coefficient {alpha} and the optical band gap E{sub g}. The linear relation of ({alpha}h{upsilon}){sup 2} as a function of photon energy h{upsilon} for the thin films illustrated that the films exhibit a direct band gap, which increases with increasing Zn content. This increasing of optical band gap was interpreted in accordance to the increasing in the cohesive energy. Optical constants, such as refractive index n, optical conductivity {sigma}{sub opt}, complex dielectric constant, relaxation time {tau} and dissipation factor tan{delta} were determined. The optical dispersion parameters E{sub 0}, E{sub d} were determined according to Wemple and Di Domenico method. - Highlights: Black-Right-Pointing-Pointer ZnSe thin film has cubic zinc blende structure while CdSe and Cd{sub 0.5}Zn{sub 0.5}Se thin films have hexagonal structure. Black-Right-Pointing-Pointer Grain size of Cd{sub 1-x}Zn{sub x}Se decreases with increasing x (x = 0, 0.5 and 1). Black-Right-Pointing-Pointer Optical band gap increases with increasing x.

Aspects of the effects of temperature and electrolyte composition on pitting corrosion of stainless steel in dairy fluids

Energy Technology Data Exchange (ETDEWEB)

Perrin, F.X. [Toulon Univ., 83 - La Garde (France). Lab. de Chimie Appliquee; Girard, H.; Pagetti, J. [Universite de Franche-Comte, Besancon (France). Lab. de Corrosion et Traitments de Surfaces; Daufin, G. [INRA, Rennes (France). Lab. de Recherches de Technologie Laitiere

2001-08-01

The pitting corrosion resistance of 304L stainless steel in dairy fluids (milks, wheys, soya juice and peptidic fluids) was studied using electrochemical measurements. The effects of temperature, chloride content and other components of the fluids was particularly investigated. In the range 30- 70 C, the pitting potential in whole milk E{sub p} is related to the temperature by the relation ln(E{sub p} + 100) = aT{sup -1} + b. Above 70 C, a further phenomenon adds to the common activation effect of temperature. Heat induced conformational changes (denaturation) of the proteins were believed to explain such a behaviour. A typical linear relationship was found between E{sub p} and the logarithm of chloride concentration. All fluids are well represented by a single relationship. Therefore, the buffering capacity of casein micelles in milks do not significantly change the pitting resistance of the oxide film. In dairy industry, the corrosion risk is usually estimated from the difference between the pitting potential and the potential of a gold electrode (E{sub g}). It is noteworthy that the pitting risk decreases when temperature increases in the temperature range 50-90 C. Such a trend was due to the strong decrease in dissolved oxygen above 50 C. Besides, in aggressive peptidic solutions, the resistance of the passive film to localized attack is directly related to the Cr, Mo and N alloy content of stainless steel. (orig.)

Application of C{sub 60}, C{sub 72} and carbon nanotubes as anode for lithium-ion batteries: A DFT study

Energy Technology Data Exchange (ETDEWEB)

Najafi, Meysam, E-mail: meysamnajafi2016@gmail.com

2017-07-01

The application of C{sub 60}, C{sub 72}, CNT (8, 0) and CNT (10, 0) as anode materials for Lithium-ion batteries were investigated by density functional theory (DFT) calculations. Results show that the average values of voltage cell (V{sub cell}) and adsorption energy (E{sub ad}) of CNT (8, 0) and CNT (10, 0) were higher than C{sub 60} and C{sub 72} ca 0.327 V and 6.52 kcal/mol, respectively. The NH{sub 2} functionalization of studied nanostructures as a strategy to improve the performance of these systems as anode materials of Lithium-ion batteries were investigated. Results show that, NH{sub 2} functionalization of studied nanostructures increase the average values of voltage cell and adsorption energy ca 0.197 V and 8.20 kcal/mol, respectively. Obtained results propose that NH{sub 2} functionalized C{sub 72} and CNT (10, 0) have larger V{sub cell} and E{sub ad} values and therefore these nanostructures have higher potential as anode material for Lithium-ion battery. - Highlights: • C{sub 60} and CNT (10, 0) as anode materials for Lithium-ion batteries were investigated. • V{sub cell} and E{sub ad} of CNT (8, 0) and CNT (10, 0) were higher than C{sub 60} and C{sub 72} ca. • NH{sub 2} functionalization of C{sub 60} improve the performance of it as anode materials of Lithium-ion batteries.

A new method of quench monitoring in liquid scintillation counting

International Nuclear Information System (INIS)

Horrocks, D.L.

1978-01-01

The quench level of different liquid scintillation counting samples is measured by comparing the responses (pulse heights) produced by the same energy electrons in each sample. The electrons utilized in the measurements are those of the maximum energy (Esub(max)) which are produced by the single Compton scattering process for the same energy gamma-rays in each sample. The Esub(max) response produced in any sample is related to the Esub(max) response produced in an unquenched, sealed standard. The difference in response on a logarithm response scale is defined as the ''H Number''. The H number is related to the counting efficiency of the desired radionuclide by measurement of a set of standards of known amounts of the radionuclide and different amounts of quench (standard quench curve). The concept of the H number has been shown to be theoretically valid. Based upon this proof, the features of the H number concept as embodied in the Beckman LS-8000 Series Liquid Scintillation Systems have been demonstrated. It has been shown that one H number is unique; it provides a method of instrument calibration and wide dynamic quench range measurements. Further, it has been demonstrated that the H number concept provides a universal quench parameter. Counting efficiency vs. H number plots are repeatable within the statistical limits of +-1% counting efficiency. By the use of the H number concept a very accurate method of automatic quench compensation (A.Q.C.) is possible. (T.G.)

Studies of annealing of neutron-produced defects in silicon by transconductance measurements of junction field-effect transistors

International Nuclear Information System (INIS)

Tokuda, Y.; Usami, A.

1978-01-01

Annealing behavior of neutron-produced defects in silicon was studied by measuring the phase angle theta of the small-signal transconductance of the junction field-effect transistors (JFET's). Three deep levels (N-1, N-2, and N-3 levels) in n-type silicon and two deep levels (P-1 and P-2 levels) in p-type silicon, introduced by irradiation, annealed gradually. Their energy levels and capture cross sections have been already reported by us. Three deep levels (P-3, P-4, and P-5 levels) were observed in annealed p-type silicon in the temperature range 150--300 0 C. For these defects, theta was measured as a function of frequency to obtain the time constant. From the temperature dependence of the time constant, assuming that capture cross sections are independent of temperature, the energy levels of P-3, P-4, and P-5 were estimated to be E/sub v/+0.21, E/sub v/+0.40, and E/sub v/+0.30 eV, respectively. The calculated hole capture cross sections of these levels were 2.2 x 10 -15 , 8.7 x 10 -14 , and 1.2 x 10 -14 cm 2 , respectively. Comparison with other published data was made. It was found that N-3 and P-2 levels corresponded to the divacancy. Furthermore, it seemed that P-3, P-4, and P-5 levels corresponded to the high-order vacancy defects

Experiments in high voltage electron microscopy. Progress report, October 31, 1976--August 1977

International Nuclear Information System (INIS)

Mitchell, T.E.; Hobbs, L.W.; Howitt, D.G.; Barnard, R.; Ro, H.

1977-07-01

High voltage electron microscopy (HVEM) is being used to study the effects of irradiation on a variety of materials. The vacancies and interstitials produced by displacement can aggregate to form dislocation loops and voids, annihilate at sinks, or enhance various diffusion processes such as precipitation and recrystallization. Threshold displacement energies, E/sub d/, have been determined for a number of fcc, bcc and hcp metals and for various oxides. In MgO, E/sub d/ is less along (100) than (110); also, E/sub d/ decreases with increasing temperature, possibly due to thermally activated escape of interstitials from recombination volumes or softening of saddle points. The effects of electron irradiation on precipitation in Al--Cu, Al--Si and Ni--Al alloys have been investigated. Precipitation respectively of theta', Si and γ' is enhanced and growth rates are explicable in terms of theories of radiation-enhanced diffusion, with D/sub rad/ approx. 10 -15 cm 2 sec -1 . In oxides, damage gives rise to interstitial dislocation loop nucleation and growth in all cases, perfect [110] loops in MgO faulted basal and prismatic loops in Al 2 O 3 . Quantitative analysis of loop growth rates in MgO gives a migration energy of 3.3 eV for anion vacancies. Other radiation effects include sublimation of MgO and decomposition of MgAl 2 O 4 and Mg 2 SiO 4 into MgO plus other phases

Study of grown-in and radiation-induced defects in indium phosphide

International Nuclear Information System (INIS)

Shaban, E.H.

1986-01-01

This research is focused on (1) conducting detailed theoretical and experimental study of grown-in and radiation-induced defects in liquid encapsulated Czohralski (LEC) grown, Zn-doped P-type indium phosphide (InP), (2) identifying the physical origin of the defects detected using Deep Level Transient Spectroscopy (DLTS) method, and (3) and developing a second-order model to interpret the presence of nonexponential capacitance transients in DLTS method. Analysis of grown-in and radiation-induced defects in P-type InP is undertaken. The main research results are summarized as follows: (1) DLTS analysis of grown-in defects in liquid LEC-grown, Zn-doped, P-type InP is made in this study. A single-hole trap of E/sub v/ + 0.52 eV is detected with a trap density of 1.8 x 10 15 cm -3 . The physical origin of this hole trap is attributed to a phosphorus vacancy or phosphorus interstitial-related defect. (2) One-MeV electron-irradiated P-type InP introduced two new hole traps, namely E/sub v/ + 0.34 and E/sub v/ + 0.58 eV with introduction rates (dN/sub T/d phi) of 0.4 and 1.2 per electron-cm, respectively. (3) A theoretical model is developed to interpret nonexponential capacitance transients in a deep-level transient spectroscopy method when the capture process competes with the dominant thermal-emission process

Transverse energy distribution, charged particle multiplicities and spectra in 16O-nucleus collisions

International Nuclear Information System (INIS)

Sunier, J.W.

1987-01-01

The HELIOS (High Energy Lepton and Ion Spectrometer) experiment, installed at the CERN Super Proton Synchrotron, proposes to examine in details the physical properties of a state of high energy created in nuclei by ultra-relativistic nucleus-nucleus collisions. It is generally believed that, at high densities or temperatures, a phase transition to a plasma of quark and gluons will occur. The dynamic of the expansion of such a plasma and its subsequent condensation into a hadron gas should markedly affect the composition and momentum distribution of the emerging particles and photons. The HELIOS experimental setup therefore combines 4π calorimetric coverage with measurements of inclusive particle spectra, two particle correlations, low and high mass lepton pairs and photons. The emphasis is placed on transverse energy flow (E/sub T/) measurements with good energy resolution, and the ability to trigger the acquisition of data in a variety of E/sub T/ ranges, thereby selecting the impact parameter or the violence of the collisions. This short note presents HELIOS results, for the most part still preliminary, on 16 O-nucleus collisions at the incident energies of 60 and 200 GeV per nucleon. The E/sub T/ distributions from Al, Ag and W targets are discussed and compared to the associated charged particle multiplicities from W. Charged particle and (converted) photon spectra measured with the external magnetic spectrometer are compared for 16 O + W and p + W collisions at 200 GeV per nucleon. 5 refs., 7 figs

Monte Carlo study of the critical behavior and magnetic properties of La{sub 2/3}Ca{sub 1/3}MnO{sub 3} thin films

Energy Technology Data Exchange (ETDEWEB)

Restrepo-Parra, E., E-mail: erestrepopa@unal.edu.c [Departamento de Fisica y Quimica, Universidad Nacional de Colombia-Sede Manizales, A.A. 127 Manizales (Colombia); Bedoya-Hincapie, C.M.; Jurado, F.J.; Riano-Rojas, J.C. [Departamento de Fisica y Quimica, Universidad Nacional de Colombia-Sede Manizales, A.A. 127 Manizales (Colombia); Restrepo, J. [Grupo de Magnetismo y Simulacion G, Instituto de Fisica, Universidad de Antioquia, A.A. 1226 Medellin (Colombia)

2010-11-15

Critical exponents offer important information concerning the interaction mechanisms near the paramagnetic to ferromagnetic transition. In this work a Monte Carlo-Metropolis simulation of the critical behavior in La{sub 2/3}Ca{sub 1/3}MnO{sub 3} thin films is addressed. Canonical ensemble averages for magnetization per site, magnetic susceptibility and specific heat of stoichiometric manganite within a three-dimensional classical Heisenberg model with nearest magnetic neighbor interactions are computed. The La{sub 2/3}Ca{sub 1/3}MnO{sub 3} thin films were simulated addressing the thickness influence and thermal dependence. In the model, Mn magnetic ions are distributed on a simple cubic lattice according to the perovskite structure of this manganite. Ferromagnetic coupling for the bonds Mn{sup 3+}-Mn{sup 3+}(e{sub g}-e{sub g}'), Mn{sup 3+}-Mn{sup 4+}(e{sub g}-d{sup 3}) and Mn{sup 3+}-Mn{sup 4+}(e{sub g}'-d{sup 3}) were taken into account. On the basis of finite-size scaling theory, our best estimates of critical exponents, linked to the ferromagnetic to paramagnetic transition, for the correlation length, specific heat, magnetization and susceptibility are, respectively: v=0.56{+-}0.01, {alpha}=0.16{+-}0.03, {beta}=0.34{+-}0.04{gamma} and {gamma}=1.17{+-}0.05. These theoretical results are consistent with the Rushbrooke equalitiy {alpha}+2{beta}+{gamma}=2.

CAMAC - supported electronic set-up for the determination of the capture cross section of the reaction 1H(n,d)γ

International Nuclear Information System (INIS)

Hutsch, J.; Moeller, K.; Moesner, J.; Neubert, W.; Pilz, W.; Schmidt, G.; Stiehler, T.; Kudin, L.G.; Spiridenkov, E.M.; Volkov, S.S.

1984-08-01

After a brief description of the physical problem the experimental apparatus and the electronic set-up for the investigation of the capture reaction 1 H(n,d)γ at E/sub n/ = 25 MeV are described. (author)

Soviet-France cooperative study of the solar corona

International Nuclear Information System (INIS)

Vsekhvsyatskij, S.K.; Dzyubenko, N.I.; Ivanchuk, V.I.; Popov, O.S.; Rubo, G.A.; Kuchmij, S.; Kuchmij, O.; Shtel'makher, G.

1981-01-01

The study continues the investigations on the solar corona performed according to the program of the Soviet-France experiment ''The white corona dynamics'' during total solar eclipses on July 10 1972 and June 30, 1973 by the expeditions of Kiev University and Paris Astrophysical Institute. The results of the study of eclipse negatives obtained on June 30 1973 in Africa are given. On the basis of new methods of photometry and colorimetry using star images up to 8.5sup(m) as the photometry standards it has been found with high accuracy the distribution of the total corona brightness up to r approximately equal to 4.5 Rsub(S) and its K- and F-corona components for E and N directions. Neither color effect nor flattening is found in the dust component (r -6 Esub(S)

Laser-induced damage study of polymer PMMA; Motale-e-ye padid-e-ye khesarat-e mavvad-e polimeri PMMA dar moghabel-e barik-e-ye laizer

Energy Technology Data Exchange (ETDEWEB)

Mansour, N

2001-07-01

This article presents the results of bulk laser-induced damage measurements in polymer PMMA at 532 nm and 1064 nm for nanosecond laser pulses. The damage thresholds were measured for focused spot sizes ranging over two orders of magnitude. In this work, self-focusing effects were verified to be absent by measurements of breakdown thresholds using both linearly and circularly polarized light. At both 1064 nm and 532 nm, the dependence of the breakdown field, E{sub B}, on the spot size, {omega}, was empirically determined to be E{sub B} = C/{radical}{omega}, where C depends on the wavelength. The extracted value for C({lambda}) at 1064 nm is larger by a factor of 5 than at 532 nm. Possible reasons for this strong dispersion and mechanism for laser-induced damage in polymer materials will be discussed.

Measurement of the Branching Fraction and Lambda-bar Polarization in B0 -> Lambda-par p pi-

Energy Technology Data Exchange (ETDEWEB)

Aubert, B.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; /Annecy, LAPP; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Martinelli, M.; Palano, A.; Pappagallo, M.; /INFN, Bari /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Battaglia, M.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /INFN, Naples /Naples U. /INFN, Naples /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /Pennsylvania U. /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison

2009-08-03

We present a measurement of the B{sup 0} {yields} {bar {Lambda}}p{pi}{sup -} branching fraction performed using the BABAR detector at the PEP-II asymmetric e{sup +}e{sup -} collider. Based on a sample of 467 x 10{sup 6} B{bar B} pairs we measure {Beta}(B{sup 0} {yields} {bar {Lambda}}p{pi}{sup -}) [3.07 {+-} 0.31(stat.) {+-} 0.23(syst.)] x 10{sup -6}. The measured differential spectrum as a function of the dibaryon invariant mass m({bar {Lambda}}p) shows a near-threshold enhancement similar to that observed in other baryonic B decays. We study the {bar {Lambda}} polarization as a function of {bar {Lambda}} energy in the B{sup 0} rest frame (E*{sub {bar {Lambda}}}) and compare it with theoretical expectations of fully longitudinally right-polarized {bar {Lambda}} at large E*{sub {bar {Lambda}}}.

Dielectric response in high Tc superconductors

Energy Technology Data Exchange (ETDEWEB)

Lopez-Aguilar, F.; Costa-Quintana, J.; Febrero, F.; Aurell, M.T.; Sanchez, A.; Munoz, J.S. (Dept. de Fisica, Grupo de Electromagnetismo, Univ. Autonoma de Barcelona (Spain)); Balle, S. (Dept. de Fisica, Univ. de les Illes Balears, Palma de Mallorca (Spain))

1989-12-01

The random phase approximation integral equation is solved for obtaining the dynamically screened interaction between d electrons (W{sub d}({omega})), p electrons (W{sub p}({omega})) and p/d electrons (W{sub pd}({omega})). Some characteristic divergences of this last interaction correspond to the plasmon frequencies which one can relate with the effective masses of the p and d electrons close to E{sub F} by means of the relation {omega}{sub p1}/{omega}{sub p2} = (m{sub 2}/m{sub 1}){sup 1/2}. Another feature of this W{sub pd}({omega}) interaction is the attractive character for low frequencies. The lowest frequency for which {epsilon}{sub pd} = 0 decreases when the localization of states close to E{sub F} arising from the x{sup 2}-y{sup 2} symmetry increases. (orig.).

Angular momentum distributions for {sup 16}O + {sup 144}Nd

Energy Technology Data Exchange (ETDEWEB)

Duchene, G.; Romain, P.; Beck, F.A.; Benet, P.; Disdier, D.; Haas, B.; Lott, B.; Rauch, V.; Scheibling, F.; Vivien, J.P. [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires]|[Strasbourg-1 Univ., 67 (France); Basu, S.K. [Bhabha Atomic Research Centre, Calcutta (India). Variable Energy Cyclotron Project; Bozek, E.; Zuber, K. [Institute of Nuclear Physics, Cracow (Poland); Di Gregorio, D.E.; Fernandez-Niello, J. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina). Dept. de Fisica

1992-12-31

Fusion cross sections have been measured for the system {sup 16} O + {sup 144} Nd at bombarding energies in the range 67 MeV {<=}E{sub lab} {<=} 90 MeV by detecting directly evaporation residues in Si detectors and in the range 60 MeV {<=}E{sub lab}{<=} 75 MeV by off-line detection of the K X-rays emitted by the radioactive evaporation residues and daughters. In order to obtain the spin distributions in the compound system gamma-ray multiplicity distributions for the most important neutron evaporation channels were also measured using a 4{pi} - BaF{sub 2} array, in conjunction with Ge detectors. Results are compared with calculations based on models that consider fluctuations in barrier height due to ground state zero point vibrations as well as couplings to various inelastic and transfer channels.

Measurement of isolated photon production in deep inelastic ep scattering

Energy Technology Data Exchange (ETDEWEB)

Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Lab., Argonne, IL (US)] (and others)

2009-09-15

Isolated photon production in deep inelastic ep scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 320 pb{sup -1}. Measurements were made in the isolated-photon transverse-energy and pseudo- rapidity ranges 4<E{sub T}{sup {gamma}}<15 GeV and -0.7<{eta}{sup {gamma}}<0.9 for exchanged photon virtualities, Q{sup 2}, in the range 105 GeV. Differential cross sections are presented for inclusive isolated photon production as functions of Q{sup 2}, x, E{sub T}{sup {gamma}} and {eta}{sup {gamma}}. Leading-logarithm parton-shower Monte Carlo simulations and perturbative QCD predictions give a reasonable description of the data over most of the kinematic range. (orig.)

Low-lying intruder state of the unbound nucleus {sup 13}Be

Energy Technology Data Exchange (ETDEWEB)

Kondo, Y., E-mail: kondo@phys.titech.ac.j [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Nakamura, T.; Satou, Y. [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Matsumoto, T.; Aoi, N. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Endo, N. [Department of Physics, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 (Japan); Fukuda, N.; Gomi, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Hashimoto, Y. [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Ishihara, M. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Kawai, S. [Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima, Tokyo 171-8501 (Japan); Kitayama, M.; Kobayashi, T.; Matsuda, Y. [Department of Physics, Tohoku University, 2-1-1 Katahira, Aoba, Sendai, Miyagi 980-8577 (Japan); Matsui, N. [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Motobayashi, T. [RIKEN Nishina Center, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan); Nakabayashi, T.; Okumura, T. [Department of Physics, Tokyo Institute of Technology, 2-12-1 Oh-Okayama, Meguro, Tokyo 152-8551 (Japan); Ong, H.J.; Onishi, T.K. [Department of Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033 (Japan)

2010-06-21

An experimental study for the unbound nucleus {sup 13}Be has been performed by means of the invariant mass method via the one-neutron removal reaction {sup 1}H({sup 14}Be,{sup 12}Be+n). A resonance has been observed at 0.51(1) MeV in the relative energy (E{sub rel}) spectrum of the {sup 12}Be+n system. The transverse momentum distribution of the {sup 12}Be+n system as well as the resonance width of 0.45(3) MeV gives evidence for the p-wave nature of the resonance. A d-wave resonance has also been observed at 2.39(5) MeV in the E{sub rel} spectrum. The observation of the low-lying p-wave resonance indicates the disappearance of the N=8 magicity in the vicinity of the neutron drip line region.

The inhibition of positronium by the chloride ion in water and the positron: Chloride reaction

International Nuclear Information System (INIS)

Beling, C.D.; Smith, F.A.

1983-01-01

A discussion is made of existing theories of Ps inhibition in the presence of Cl - ions. Our favoured interpretation of the data uses the thermalised pre-solvated positron as a common precursor of Ps and e + Cl - . Consideration is given to the prevention of solvation by the strong electric fields in the vicinity of Cl - ions, assuming best estimates for the solvation time, positron mobility and intermolecular spacing. An expression for the Ps inhibition constant K is derived on the basis of diffusive capture. The observed enhancement of Ps yield at higher Cl - concentrations is attributed to the scavenging by the Cl - ion of highly mobile species such as H 2 + O within times approx.=10 -14 s. Dissociation between e + Cl - and the solvated state esub(s) + is suggested as the cause of the ''missing fraction''. (orig.)

THM determination of the 65 keV resonance strength intervening in the {sup 17}O(p,α){sup 14}N reaction rate

Energy Technology Data Exchange (ETDEWEB)

Sergi, M. L.; La Cognata, M.; Pizzone, R. G. [INFN-Laboratori Nazionali del Sud, Catania (Italy); Spitaleri, C.; Cherubini, S.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S. [Università di Catania, Catania, Italy and INFN-Laboratori Nazionali del Sud, Catania (Italy); Burjan, S. V.; Hons, Z.; Kroha, V. [Nuclear Physics Institute of ASCR Rez near Prague (Czech Republic); Coc, A. [CSNSM, UMR 8609, CNRS/IN2P3 and Universitè Paris Sud 11, Bâtiment 104, 91405 Orsay Campus (France); Gulino, M.; Tumino, A. [Università di Catania, Catania, Italy and INFN-Laboratori Nazionali del Sud, Catania, Italy and Universitá Kore di Enna, Enna (Italy); Hammache, F. [IPN, IN2P3-CNRS et Université de Paris-Sud 91406 Orsay Cedex (France); Irgaziev, B. [GIK Institute of Engineering Sciences and Technology Topi District Swabi NWFP (Pakistan); Kiss, G. G.; Somorjai, E. [ATOMKI, Debrecen (Hungary); Lamia, L. [Università di Catania, Catania (Italy); Mukhamedzhanov, A. [Cyclotron Institute,Texas A and M University College Station (United States); and others

2015-02-24

The {sup 17}O(p,α){sup 14}N reaction is of paramount importance for the nucleosynthesis in a number of stellar sites, including red giants (RG), asymptotic giant branch (AGB) stars, massive stars and classical novae. We report on the indirect study of the {sup 17}O(p,α){sup 14}N reaction via the Trojan Horse Method by applying the approach recently developed for extracting the resonance strength of the narrow resonance at E{sub c.m.}{sup R} = 65 keV (E{sub X} =5.673 MeV). The strength of the 65 keV resonance in the {sup 17}O(p,α){sup 14}N reaction, measured by means of the THM, has been used to renormalize the corresponding resonance strength in the {sup 17}O+p radiative capture channel.

A tewlve detector coincidence spectrometer for on-line and off-line measurements of nuclear g-factors

International Nuclear Information System (INIS)

Alfter, I.; Bodenstedt, E.; Hamer, B.; Hoff, J. van den; Knichel, W.; Muenning, H.; Piel, S.; Schueth, J.; Sajok, R.

1992-01-01

A twelve detector γ-γ directional correlation setup is described which has been designed and constructed for high precision on-line and off-line IPAC measurements. A ring of twelve BaF 2 detectors which may be replaced by Ge detectors is arranged around a superconducting magnet providing a maximum magnetic field of 4.5 T. In on-line experiments the magnetic field has the direction of the beam which passes through a central bore of the magnet. The data acquisition system stores directly the Esub(γ 1 )-Esub(γ 2 ) coincidence matrices for all 66 two-detector combinations in two 8 Mbyte RAMs, one for each of the two field directions. This allows a very fast data evaluation with a small on-line computer. The apparatus got into operation one-and-a-halve years ago and revealed excellent properties. (orig.)

Photoproduction of isolated photons, inclusively and with a jet, at HERA

Energy Technology Data Exchange (ETDEWEB)

Abramowicz, H. [Raymond and Beverly Sackler Faculty of Exact Sciences, School of Physics, Tel Aviv University, Tel Aviv (Israel); Abt, I. [Max-Planck-Institut für Physik, München (Germany); Adamczyk, L. [AGH—University of Science and Technology, Faculty of Physics and Applied Computer Science, Krakow (Poland); Adamus, M. [National Centre for Nuclear Research, Warsaw (Poland); Aggarwal, R. [Panjab University, Department of Physics, Chandigarh (India); Antonelli, S. [University and INFN Bologna, Bologna (Italy); Arslan, O. [Physikalisches Institut der Universität Bonn, Bonn (Germany); Aushev, V. [Institute for Nuclear Research, National Academy of Sciences, Kyiv (Ukraine); Department of Nuclear Physics, National Taras Shevchenko University of Kyiv, Kyiv (Ukraine); Aushev, Y. [Department of Nuclear Physics, National Taras Shevchenko University of Kyiv, Kyiv (Ukraine); Bachynska, O. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Barakbaev, A.N. [Institute of Physics and Technology of Ministry of Education and Science of Kazakhstan, Almaty (Kazakhstan); Bartosik, N.; Behnke, O.; Behr, J.; Behrens, U. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Bertolin, A. [INFN Padova, Padova (Italy); Bhadra, S. [Department of Physics, York University, Ontario, M3J 1P3 (Canada); Bloch, I. [Deutsches Elektronen-Synchrotron DESY, Zeuthen (Germany); Bokhonov, V. [Institute for Nuclear Research, National Academy of Sciences, Kyiv (Ukraine); Boos, E.G. [Institute of Physics and Technology of Ministry of Education and Science of Kazakhstan, Almaty (Kazakhstan); and others

2014-03-07

The photoproduction of isolated photons, both inclusive and together with a jet, has been measured with the ZEUS detector at HERA using an integrated luminosity of 374 pb{sup −1}. Differential cross sections are presented in the isolated-photon transverse-energy and pseudorapidity ranges 6<E{sub T}{sup γ}<15 GeV and −0.7<η{sup γ}<0.9, and for jet transverse-energy and pseudorapidity ranges 4<E{sub T}{sup jet}<35 GeV and −1.5<η{sup jet}<1.8, for exchanged-photon virtualities Q{sup 2}<1 GeV{sup 2}. Differential cross sections are also presented for inclusive isolated-photon production as functions of the transverse energy and pseudorapidity of the photon. Higher-order theoretical calculations are compared to the results.

Hopping model for the non-Debye dielectric response in ionic crystals

International Nuclear Information System (INIS)

Wang, J.C.; Bates, J.B.

1988-10-01

A model based on ion hopping in potential double-wells is proposed to explain the non-Debye dielectric response in solids. Relying on some assumptions, an attempt is made to remove the ''average'' nature of previous diffusion theories. This results in a distribution of activation energies, G(E), which decays exponentially on both sides of some given value E/sub o/. It is shown that the existence of a dielectric loss peak is a result of the decay of G(E) for E > E 0 the constant-phase-angle behavior above the loss peak is associated with the decay of G(E) for E 0 , and G(E) can produce all the main features of the empirical Havriliak-Negami function. An interesting property of this G(E) is that it broadens with increasing temperature, consistent with many experimental observations. 18 refs., 3 figs

The international ISOE programme. ISOE European technical centre activities

International Nuclear Information System (INIS)

Ascenzo, L. d'; Crouail, P.; Levy, F.; Livolsi, P.; Schieber, C.; Lefaure, C.

1996-01-01

The CEPN has been involved from the beginning in the NEA Information System on Occupational Exposure (ISOE). As ISOE European Technical Centre, the CEPN is responsible for the collection and distribution of European data to the various ISOE partners, the collection of data from the other regional technical centres, and the custodianship of the full ISOE data base. This full data base is updated annually and distributed to all the European participating utilities and to other Regional Technical Centres. The European data are also sent to the European Commission (EC) as a contribution to their own occupational exposure data base. In addition to these activities, the CEPN has developed two computer programmes under Windows to facilitate the management of ISOE data bases. The first software, called ASPIC, allows participating utilities to electronically complete NEA1 and NEA3 questionnaires, as well as to consult the NEA3 data base using key words search routine. This software is available in six different languages. The second programme is a relational data base for the performance of statistical analyses using data from NEA1. The CEPN also contributes significantly to the efficient flow of information through the ISOE Network. This includes participation in the preparation and distribution of the ISOE Annual Report (which presents and analyses NEAI data), ISOE Information Sheets (providing short synthesis using NEA1 and NEA3 data), and Technical Reports. Participating Authorities and Utilities have each made information requests to the CEPN concerning dosimetric data, radiation protection experiences, policies and practices. Some examples of these requests, and of the types of data provided, will be presented. (author)

Fluctuation of shower front structure: measurements, Esub(p) approximately 1018 eV

International Nuclear Information System (INIS)

Barrett, M.L.; Watson, A.A.; Wild, P.; Wilson, J.G.

1975-01-01

The work of Watson and Wilson (1974) on the introduction of a parameter of shower-front development fluctuations has been extended using a purpose-built recording system yielding results over an increased distance range from the shower axis. An exhaustive study of possible spurious sources of the observed features has been undertaken, and none of significance have been identified. The values of the fluctuation parameter now given are considered well-established. (orig.) [de

The renormalized Hamiltonian truncation method in the large E{sub T} expansion

Energy Technology Data Exchange (ETDEWEB)

Elias-Miró, J. [SISSA and INFN, I-34136 Trieste (Italy); Montull, M. [Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology (BIST), Campus UAB, E-08193 Bellaterra (Spain); Riembau, M. [Institut de Física d’Altes Energies (IFAE), Barcelona Institute of Science and Technology (BIST), Campus UAB, E-08193 Bellaterra (Spain); DESY, Notkestrasse 85, 22607 Hamburg (Germany)

2016-04-22

Hamiltonian Truncation Methods are a useful numerical tool to study strongly coupled QFTs. In this work we present a new method to compute the exact corrections, at any order, in the Hamiltonian Truncation approach presented by Rychkov et al. in refs. http://dx.doi.org/10.1103/PhysRevD.91.085011; http://dx.doi.org/10.1103/PhysRevD.93.065014; http://dx.doi.org/10.1103/PhysRevD.91.025005. The method is general but as an example we calculate the exact g{sup 2} and some of the g{sup 3} contributions for the ϕ{sup 4} theory in two dimensions. The coefficients of the local expansion calculated in ref. http://dx.doi.org/10.1103/PhysRevD.91.085011 are shown to be given by phase space integrals. In addition we find new approximations to speed up the numerical calculations and implement them to compute the lowest energy levels at strong coupling. A simple diagrammatic representation of the corrections and various tests are also introduced.

Measurements of vibrational excitation of N2, CO, and NO by low energy proton impact

International Nuclear Information System (INIS)

Krutein, J.; Linder, F.

1979-01-01

Differential scattering experiments are reported for proton impact on N 2 , CO, and NO in the energy range E/sub lab/=30--80 eV. The measurements include the range of very small scattering angles around 0 0 as well as the rainbow region. The vibrationally resolved energy-loss spectra show a relatively low vibrational inelasticity for all three systems. Differential cross sections, transition probabilities, and the mean vibrational energy transfer are presented. Rotational excitation is indicated by the broadening of the energy-loss peaks which is most significant for H + --NO. The small-angle scattering data for vibrational excitation in CO show good agreement with the impact parameter theory using the known long-range interactions for this system

Production of $\\phi$ -mesons in p+p, p+Pb and central Pb+Pb collisions at $E_{beam}$=158 A GeV

CERN Document Server

Afanasiev, S V; Bächler, J; Barna, D; Barnby, L S; Bartke, Jerzy; Barton, R A; Betev, L; Bialkowska, H; Billmeier, A; Blume, C; Blyth, C O; Boimska, B; Bracinik, J; Brady, F P; Brun, R; Buncic, P; Carr, L; Cebra, D; Cooper, G E; Cramer, J G; Csató, P; Eckardt, V; Eckhardt, F; Ferenc, D; Fischer, H G; Fodor, Z; Foka, P Y; Freund, P; Friese, V; Ftácnik, J; Gál, J; Ganz, R E; Gazdzicki, M; Gladysz-Dziadus, E; Grebieszkow, J; Harris, J W; Hegyi, S; Hlinka, V; Höhne, C; Igo, G; Ivanov, M; Jacobs, P; Janik, R; Jones, P G; Kadija, K; Kolesnikov, V I; Kowalski, M; Lasiuk, B; Lévai, Peter; Malakhov, A I; Margetis, S; Markert, C; Mayes, B W; Melkumov, G L; Mischke, A; Molnár, J; Nelson, J M; Odyniec, Grazyna Janina; Oldenburg, M; Pálla, G; Panagiotou, A D; Petridis, A; Pikna, M; Pinsky, L; Poskanzer, A M; Prindle, D J; Pühlhofer, F; Reid, J G; Renfordt, R E; Retyk, W; Ritter, H G; Röhrich, D; Roland, C; Roland, G; Rybicki, A; Sammer, T; Sandoval, A; Sann, H; Semenov, A Yu; Schäfer, E; Schmitz, N; Seyboth, P; Siklér, F; Sitár, B; Skrzypczak, E; Snellings, R; Squier, G T A; Stock, Reinhard; Strmen, P; Ströbele, H; Susa, T; Szarka, I; Szentpétery, I; Sziklai, J; Toy, M; Trainor, T A; Trentalange, S; Ullrich, T S; Varga, D; Vassiliou, Maria; Veres, G I; Vesztergombi, G; Voloshin, S A; Vranic, D; Wang, F; Weerasundara, D D; Wenig, S; Whitten, C; Xu, N; Yates, T A; Yoo, I K; Zimányi, J

2000-01-01

Yields and phase space distributions of phi -mesons emitted from p+p (minimum bias trigger), p+Pb (at various centralities) and central Pb +Pb collisions are reported (E/sub beam/=158 A GeV). The decay phi to K/sup +/K/sup -/ was used for identification. The phi / pi ratio is found to increase by a factor of 3.0+or-0.7 from inelastic p+p to central Pb+Pb. Significant enhancement in this ratio is also observed in subclasses of p+p events (characterized by high charged-particle multiplicity) as well as in the forward hemisphere of central p+Pb collisions. In Pb+Pb no shift or significant broadening of the phi - peak is seen. (28 refs).