WorldWideScience
1

Spectroscopic characterization of alkane radical cations: Pt. 1  

International Nuclear Information System (INIS)

Radical cations of various 3-methylalkanes (C_6-C_1_4) have been produced and stabilized by #gamma#-irradiation of the corresponding neutral compounds in saturated chlorofluorocarbon and perfluorocarbon matrices at 77 K. The perfluorocarbon matrices appeared more suitable for studies of the lighter radical cations, whereas the chlorofluorocarbon matrices were more suited for studies of the heavier radical cations; intermediary cations could be studied in both types of matrices. After irradiation, electronic absorptions associated with both the matrix and the alkane additive were observed. Pure spectra of the 3-methylalkane radical cations were obtained by difference spectrometry, after selective elimination of these cations by illumination. The electronic absorption spectra of the 3-methylalkane radical cations consist in all cases of a single broad absorption band. The spectral position of this band shifts to longer wavelengths with increasing ...

1989-01-01

2

Factors influencing the in vitro interaction between immunoglobulins and isolated C1: a critical study  

UK PubMed Central (United Kingdom)

The C1 fixation test is widely used for the study of the interaction between immunoglobulins, their fragments and the complement system. Some factors influencing the apparent extent of the C1 fixation...Full Text Available

1978-05-01

3

Pseudomonas aeruginosa tssC1 Links Type VI Secretion and Biofilm-Specific Antibiotic Resistance.  

Science.gov (United States)

Biofilm-specific antibiotic resistance is influenced by multiple factors. We demonstrated that Pseudomonas aeruginosa tssC1, a gene implicated in type VI secretion (T6S), is important for resistance of biofilms to a subset of antibiotics. We showed that tssC1 expression is induced in biofilms and confirmed that tssC1 is required for T6S. PMID:21784934

2011-07-22

4

Bender-Dunne Orthogonal Polynomials, Quasi-Exact Solvability and Asymptotic Iteration Method for Rabi Hamiltonian  

International Nuclear Information System (INIS)

We present a method for obtaining the quasi-exact solutions of the Rabi Hamiltonian in the framework of the asymptotic iteration method (AIM). The energy eigenvalues, the eigenfunctions and the associated Bender-Dunne orthogonal polynomials are deduced. We show (i) that orthogonal polynomials are generated from the upper limit (i.e., truncation limit) of polynomial solutions deduced from AIM, and (ii) prove to have nonpositive norm. (authors)

2011-08-01

5

Regulation of the urea active transporter gene (DUR3) in Saccharomyces cerevisiae.  

UK PubMed Central (United Kingdom)

The DUR3 gene, which encodes a component required for active transport of urea in Saccharomyces cerevisiae, has been isolated, and its sequence has been determined. The deduced DUR3 protein profile...Full Text Available

1993-08-01

6

Examples of degenerated matter in astrophysics: white dwarf and neutron stars  

Energy Technology Data Exchange (ETDEWEB)

Main features of star evolution are recalled. Then the general structure of white dwarf stars is examined. From the equation of state of an electron gas completely degenerated are deduced: mechanical equilibrium, Viriel theorem, mass-radius relationship and Chandrasekhar limit. These results are applied to neutron stars.

1982-06-01

7

Deducing the pathogenic contribution of recessive ABCA4 alleles in an outbred population  

UK PubMed Central (United Kingdom)

Accurate prediction of the pathogenic effects of specific genotypes is important for the design and execution of clinical trials as well as for meaningful counseling of individual patients. However,...Full Text Available

2010-10-01

8

A hypothetical model for the peptide binding domain of hsp70 based on the peptide binding domain of HLA.  

UK PubMed Central (United Kingdom)

The sequences of the peptide binding domains of 33 70 kd heat shock proteins (hsp70) have been aligned and a consensus secondary structure has been deduced. Individual members showed no significant...Full Text Available

1991-05-01

9

Theoretical calculation for the elastic wave velocities and thermodynamic functions of graphite  

International Nuclear Information System (INIS)

Based on the generalized gradient approximation (GGA) of density functional theory (DFT) and the full-potential linearized augmented plane wave (FLAPW) at the level including all electrons, the lattice parameters of graphite are calculated and optimized. Some elastic wave velocities transmitted in graphite are deduced. Using the methods of elastic wave velocity method and the atomic displacement method, the Debye frequency of graphite is obtained. The standard heat capacity, entropy, sublimation enthalpy of graphite is deduced at 289.5 k and 1 atm. The calculated results are discussed and compared with experimental data. (authors)

2006-06-01

10

Untitled - NASA Technical Report Server (NTRS)  

Science.gov (United States)

Joint Committee on Atomic Energy. Comgress of the United States. Washington, D. C.. 1 - Chief, Life Sciences Division. A m y Research Office ...

11

Battalion Tactical Plays--Can They Increase Combat Power  

Science.gov (United States)

... Tactical plays are more than drills or standard operating proc-edures. ... IN * BYPMASS OR BREECH MINEFIELD ON FLANK SIXE (TM I3A C1 10 ...

1988-11-10

12

A quenched c = 1 critical matrix model  

Energy Technology Data Exchange (ETDEWEB)

We study a variant of the Penner-Distler-Vafa model, proposed as a c = 1 quantum gravity: quenched' matrix model with logarithmic potential. The model is exactly soluble, and exhibits a two-cut branching as observed in multicritical unitary matrix models and multicut Hermitian matrix models. Using analytic continuation of the power in the conventional polynomial potential, we also show that both the Penner-Distler-Vafa model and our quenched' matrix model satisfy Virasoro algebra constraints.

1990-12-01

13

Phantom and animal imaging studies using PLS synchrotron X-rays  

CERN Document Server

Ultra-high resolution radiographs can be obtained using synchrotron X-rays. A collaboration team consisting of K-JIST, POSTECH and YUMC has recently commissioned a new beamline (5C1) at Pohang Light Source (PLS) in Korea for medical applications using phase contrast radiology. Relatively simple image acquisition systems were set up on 5C1 beamline, and imaging studies were performed for resolution test patterns, mammographic phantom, and animals. Resolution test patterns and mammographic phantom images showed much better image resolution and quality with the 5C1 imaging system than the mammography system. Both fish and mouse images with 5C1 imaging system also showed much better image resolution with great details of organs and anatomy compared to those obtained with a conventional mammography system. A simple and ...

2001-01-01

14

Molar extinction coefficients of some fatty acids  

International Nuclear Information System (INIS)

The attenuation of gamma rays in some fatty acids, viz. formic acid (CH_2O_2), acetic acid (C_2H_4O_2), propionic acid (C_3H_6O_2), butyric acid (C_4H_8O_2), n-hexanoic acid (C_6H_1_2O_2), n-caprylic acid (C_8H_1_6O_2), lauric acid (C_1_2H_2_4O_2), myristic acid (C_1_4H_2_8O_2), palmitic acid (C_1_6H_3_2O_2), oleic acid (C_1_8H_3_4O_2) and stearic acid (C_1_8H_3_6O_2), has been measured at the photon energies 81, 356, 511, 662, 1173 and 1332 keV. Experimental values for the molar extinction coefficient, the effective atomic number and the electron density have been derived and compared with theoretical calculations. There is good agreement between experiment and theory.

2002-10-01

15

Polarized neutron diffraction study of CePd{sub 3}  

Energy Technology Data Exchange (ETDEWEB)

We have performed polarized neutron diffraction measurements on the intermediate valence compound CePd{sub 3} using the D3 spectrometer at the ILL. The results show that at low temperatures, 1.7 K, as well as at 100 K, the field-induced magnetic amplitudes measured in a field of 4.6 T could be interpreted in terms of two contributions: a 4f-type contribution with a Ce{sup 3+} form factor, and an extra delocalized contribution (relatively narrow in q-extent). In particular, we find that the values of the 4f moment deduced from the extrapolation of the neutron data to Q=0 are systematically lower than the values deduced from bulk magnetization measurements performed on the same sample. This difference can be ascribed to a possible positive polarization of the conduction band which is similar at both temperatures.

2004-07-15

16

The competition of neutrino energy loss due to the pair, photo-, plasma process at the late stages of stellar evolution  

International Nuclear Information System (INIS)

Based on the Weinberg-Salam theory, the competition of the Neutrino Energy Loss (NEL) rates due to the pair, photo- and plasma process are canvassed. The ratio factor C1, C2 and C3 which correspond the different contributions of the pair, photo- and plasma neutrino process to those of the total NEL rates are accurately taken into account. The ratio factors are very sensitive to the temperature and density. The ratio factor C2 always is lower than the ratio factor C1 and C3. The pair NEL process is the dominant contribution before the crossed point O(C1=C3=0.45) and the plasma NEL process will be the main dominant contribution after the crossed point O. With increasing temperature, the crossed point O will move to the direction of higher density. (authors)

2009-01-01

17

How microcystin-degrading bacteria express microcystin degradation activity  

British Library Electronic Table of Contents (United Kingdom)

Abstract Alkali tolerance and the mechanism of microcystin (MC) degradation were investigated in the MC-degrading bacterial species, Sphingopyxis sp. C-1, to better understand the increased MC degradation under the alkaline conditions that arise during the disappearance of water blooms. MC-degrading bacteria harbour mlrA, mlrB and mlrC that encode MC-degrading enzymes. Sphingopyxis sp. C-1 also possesses these genes, as well as the mlrD gene that has been assumed to encode MC and its degradation transporter. This study demonstrated that MC degradation activity was promoted by the intermittent addition of microcystin-LR (MCLR) to cultures of strain C-1. That the expression of mlrA, mlrB and mlrC is induced by MCLR also was indicated, whereas that of mlrA and mlrB is induced by the MCLR degr...

2011-01-01

18

The analysis of coupled heat and particle transport in Tokamaks by means of Fourier transform  

Energy Technology Data Exchange (ETDEWEB)

A method to deduce the 2 x 2 transport matrix for coupled heat and particle transport in Tokamaks is proposed. The method applies to perturbative experiments, and is based on a Fourier transform of the measured signals of temperature and density. By analyzing different linear combinations of temperature and density, the eigenvectors and eigenvalues of the transport matrix are determined. The method is tested for a number of illustrative cases using simulated data, and the sensitivity to noise on the signals is evaluated. (author).

1992-04-01

19

Symbiotic star BF Cygni from 1965 to 1970  

Science.gov (United States)

Sixteen spectra of the symbiotic star BF Cygni covering the period 1965-- 1970 were investigated. Variations of the line intensities, the Balmer decrements, the color, and electronic temperatures are given. Approximate values of the electron density were deduced in order to derive an order of magnitude for the sizes of the emitting regions of BF Cygni. A crude stratification and evolution model is proposed. (auth)

1973-03-01

20

Radial distribution function and second virial coefficient for interacting bosons  

International Nuclear Information System (INIS)

The radial distribution function and the second virial coefficient of interacting bosons have been studied. The second virial coefficient has been deduced theoretically and is in good agreement with experimental values. The third virial coefficient has been calculated from the experimental values of the pressure. (Auth.).

1976-01-01

21

Prediction of the gain degradation induced by neutrons in dipolar transistors: spectrum dependence, electrical characteristic correlations  

International Nuclear Information System (INIS)

An original evaluating method of gain degradation has been found for neutron irradiated transistors. It establishes a correlation between degradation and the product of two coefficients: spectra factor and an electrical parameter which is measured or directly deduced from manufacturer's data. Equivalence for several type of spectra (fission, 14MeV and degradation sensitivity to electrical parameters values of individual components of a batch are obtained.

1974-06-01

22

Optical and statistical model calculation of the americium 242m capture cross section  

International Nuclear Information System (INIS)

The capture cross sections of Am 242m can be deduced from resonances analysis at low energy and computed with theoretical models at high energy. In this work, a coherent set of cross sections which reproduced the experimental values of the fission cross sections is computed. These calculations were performed for an energy of the incoming neutron between 1 keV and 1 MeV.

23

Nitrogen isotope identification by Bragg-curve spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

Projectilelike fragments following the 80 MeV /sup 16/O+/sup 27/Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.

1984-07-14

24

Nitrogen isotope identification by Bragg-curve spectroscopy  

International Nuclear Information System (INIS)

Projectilelike fragments following the 80 MeV "1"6O+"2"7Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.

25

Measurement of the susceptibility of solid "3He along the melting curve from 20 mK down to the nuclear ordering temperature  

International Nuclear Information System (INIS)

The susceptibility of solid "3He is deduced from multiple echoes observed in pulsed NMR experiments. It follows a Curie Weiss law at high temperature, increases faster than this law below 5 mK and drops abruptly around 1 mK. (Auth.).

1977-02-01

26

Mean magnetic moments of polycrystalline Ce compounds in a tetragonal crystal field  

International Nuclear Information System (INIS)

An alternative and graphical representation of the magnetic moment and the effective paramagnetic moment for polycrystalline Ce compounds with tetragonal site symmetry is described. The reduced moments can be calculated by means of standard perturbation theory. The calculated values deduced from the ground states of CeCu_2Si_2, CeRu_2Si_2, and CePd_2Si_2 polycrystals are compared with experimental magnetic moments.

27

Marsden-Ratiu reduction and W_3"2 algebra  

International Nuclear Information System (INIS)

The W_3"2 algebra is deduced by the Marsden-Ratiu reduction in the bi-Hamiltonian framework proposed by Magri et al and compared with the usual derivations via the Drinfeld-Sokolov formalism. It is observed that the choice of A in the first Poisson tensor must be different for W_3"2 algebra. (orig.).

1997-01-01

28

Investigation of lifetimes in the dipole band of {sup 139}Sm  

Energy Technology Data Exchange (ETDEWEB)

Lifetimes have been measured for a dipole band in {sup 139}Sm using DSAM. The deduced B(M1) and B(E2) values as well as B(M1)/B(E2) ratios are compared with calculations in the framework of the TAC (Tilted Axis Cranking) and SPAC (Shears mechanism with Principal Axis Cranking) models. The dipole band in {sup 139}Sm can be considered as a magnetic rotational band with a prolate or triaxial nuclear deformation. (orig.)

2008-09-15

29

Investigation of lifetimes in dipole bands of {sup 142}Gd  

Energy Technology Data Exchange (ETDEWEB)

Lifetimes have been measured for dipole bands in {sup 142}Gd using DSAM. The deduced B(M1) and B(E2) values as well as B(M1)/B(E2) ratios are compared with calculations in the framework of the TAC (Tilted Axis Cranking) and SPAC (shears mechanism with Principal Axis Cranking) models. The dipole bands DB1 to DB4 can be interpreted as magnetic rotational bands. (orig.)

2005-02-01

30

Intrinsic and extrinsic crossluminescence in ionic crystals  

Energy Technology Data Exchange (ETDEWEB)

Intrinsic crossluminescence (CRL) of CsBr, CsCl, and of BaF{sub 2} was investigated with electron-beam and synchrotron radiation excitation. From the CRL spectra, the excitation spectra and the reflectivity, energy level schemes were deduced. Extrinsic CRL was observed changing either the initial (CsCl:Br{sup -}) or the final (RbCl:Cs{sup +}; KCl:Cs{sup +}) state of CRL by doping. (author).

1991-01-01

31

Intrinsic and extrinsic crossluminescence in ionic crystals  

International Nuclear Information System (INIS)

Intrinsic crossluminescence (CRL) of CsBr, CsCl, and of BaF_2 was investigated with electron-beam and synchrotron radiation excitation. From the CRL spectra, the excitation spectra and the reflectivity, energy level schemes were deduced. Extrinsic CRL was observed changing either the initial (CsCl:Br"-) or the final (RbCl:Cs"+; KCl:Cs"+) state of CRL by doping. (author).

1990-09-03

32

Gauge theory, topological strings, and S-duality  

Energy Technology Data Exchange (ETDEWEB)

We offer a derivation of the duality between the topological U(1) gauge theory on a Calabi-Yau 3-fold and the topological A-model on the same manifold. This duality was conjectured recently by Iqbal, Nekrasov, Okounkov, and Vafa. We deduce it from the S-duality of the IIB superstring. We also argue that the mirror version of this duality relates the topological B-model on a Calabi-Yau 3-fold and a topological sector of the Type IIA Little String Theory on the same manifold. (author)

2004-09-01

33

Gamma-ray spectra from neutron capture on /sup 87/Sr  

Energy Technology Data Exchange (ETDEWEB)

The gamma-ray spectrum following neutron capture on /sup 87/Sr was measured at 3 neutron energies: E/sub n/ = thermal, 2 keV, and 24 keV. Gamma rays were detected in a three-crystal Ge(Li)-NaI-NaI pair spectrometer. Gamma-ray intensities deduced from these spectra by spectral unfolding are presented.

1981-07-01

34

Energy flux operator, current conservation and the formal Fourier's law  

International Nuclear Information System (INIS)

By revisiting previous definitions, we show that one can define an energy current operator that satisfies the continuity equation for a general Hamiltonian in one dimension. This expression is useful for studying electronic, phononic and photonic energy flow in linear systems and in hybrid structures. The definition allows us to deduce the necessary conditions that result in current conservation for general-statistics systems. The discrete form of the Fourier's law of heat conduction naturally emerges in the present definition.

2009-01-16

35

Comprehensive, nonintercepting electron-beam diagnostics using spontaneous emission  

Energy Technology Data Exchange (ETDEWEB)

Characterization and optimization of electron-beam parameters are important aspects of optimizing free-electron laser (FEL) performance. The visible spontaneous emission ({lambda}{approximately}650 nm) from the 5-meter long undulator of the Boeing FEL experiment can be characterized in sufficient detail with a streak/spectrometer to deduce time-resolved electron-beam spatial position and profile, micropulse duration, and energy. 7 refs., 13 figs., 2 tabs.

1989-01-01

36

Closed smooth strings on a torus  

Energy Technology Data Exchange (ETDEWEB)

The free energy of a gas of closed strings with extrinsic curvature (smooth strings) is evaluated on a torus. This is compared with the free energy of a collection of free particles, and hence the mass spectrum of excitations of the smooth strings is deduced. It is found that above a critical value of the coupling constant of the curvature term the spectrum is free of tachyons. Furthermore, there are no massless spin-2 excitations. The absence of massless spin-2 fields is a consequence of the fact that the smooth-string theory is not modular invariant.

1988-02-15

37

Beta and gamma decay heat measurements between 0.1s - 50,000s for neturon fission of {sup 235}U, {sup 238}U and {sup 239}Pu. Progress report, June 1, 1992--December 31, 1994  

Energy Technology Data Exchange (ETDEWEB)

In the investigations reported here, a helium-jet/tape-transport system was used for the rapid transfer of fission products to a low-background environment where their aggregate beta and gamma-ray spectra were measured as a function of delay time after neutron induced fission of {sup 235}U, {sup 238}U and {sup 239}Pu. Beta and gamma-ray energy distributions have been deduced for delay times as short as 0.2 s and extending out to 100,000s. Instrumentation development during the initial phase of the project included: (1) assembly and characterization of a NaI(Tl) spectrometer for determining aggregate gamma-ray energy distributions, (2) development and characterization of a beta spectrometer (having excellent gamma-ray rejection) for measuring aggregate beta-particle energy distributions, (3) assembly and characterization of a Compton-suppressed HPGe spectrometer for determining gamma-ray intensities of individual fission products to deduce ...

1997-05-01

38

UK CDHF for STP UK  

Science.gov (United States)

Original holdings are now kept by the World Data Centre C1 at RAL: http://wdcc1. bnsc.rl.ac.uk MODS DOY = 246 ADID_REF Not applicable LOGICAL_FILE_ID ...

39

Tumor-derived extracellular mutations of PTPRT/PTP? are deficient in cell adhesion  

UK PubMed Central (United Kingdom)

Receptor protein tyrosine phosphatase T (PTPRT/PTPc1;) is frequently mutated in human cancers including colon, lung, gastric and skin cancers. More than half of the identified tumor-derived...Full Text Available

2008-07-01

40

Tritium and "1"4C in the environment around Wolsong nuclear power plant  

International Nuclear Information System (INIS)

To understand the environmental dispersion trend of "3H and "1"4C discharged from the Wolsung nuclear power plant, the present levels of "3H and "1"4C in environmental samples in the vicinity of the Wolsong site were studied. During 1992 through 2002, the annual means of HTO and "1"4C concentrations in air collected at three sampling stations around Wolsong nuclear power plant were in the range of 1.13 #approx# 29.2 Bq m"-"3 and 0.33 #approx# 0.40 Bq g-C"-"1 respectively, decreasing with distance from the site. The annual mean of TFWT concentrations in pine needle was in the range of 104 #approx# 790 Bq L"-"1 at N-1 and 62.8 #approx# 298 Bq L"-"1 at S"-"2, while the annual mean of "1"4C concentration was in the range of 0.335 #approx# 0.897 g-C"-"1 at N-1 and 0.254 #approx# 0.332 Bq g-C"-"1 #approx# at S"-"2, showing elevated value than a 0.25 Bq ...

2003-09-01

41

Five-Year Wilkinson Microwave Anisotropy Probe (WMAP1 - LAMBDA - NASA  

Science.gov (United States)

If we decompose C1 using SVD the parameter covariance matrix can be inverted to ... However, we can analyze the parameter covariance matrix directly by ...

42

Two-dimensional (half-) integer spin conformal theories with central charge c < 1  

Energy Technology Data Exchange (ETDEWEB)

A generalized integral representation involving two types of charges is explored to construct correlation functions on the plane for c = 1 - 6/(m(m + 1)) < 1 discrete unitary Virasoro series. The various local operator product algebras emerging contain integer, or half-integer, spin fields along with scalar fields. The examples also include a generalization for arbitrary m of the Z/sub 2/sup -// statistics of the Ising model order-disorder fields.

1988-01-01

43

Decay of "1"7"7Ta composite system: comparison of excitation functions for the reaction residues occurring in "1"2C + "1"6"5Ho and "1"4N + "1"6"3Dy reactions  

International Nuclear Information System (INIS)

In the reactions induced by heavy ions, the study of breakup of heavy ions followed by the fusion of one of the fragments with the target has been of great interest. The present experiments has been performed with a view to compare the measured excitation functions for the same decay channels in "1"2C + "1"6"5Ho and "1"4N + "1"6"3Dy systems

2000-12-01

44

Two dimensional power spectral density measurements of X-rayoptics with the Micromap interferometric microscope  

Energy Technology Data Exchange (ETDEWEB)

A procedure and software have been developed to transform the area distribution of the residual surface heights available from the measurement with the Micromap interferometric microscope into a two-dimensional (2D) power spectral density (PSD) distribution of the surface height. The procedure incorporates correction of one of the spectral distortions of the PSD measurement. The distortion appears as a shape difference between the tangential and sagittal PSD spectra deduced from the 2D PSD distribution for an isotropic surface. A detailed investigation of the origin of the anisotropy was performed, and a mathematical model was developed and used to correct the distortion. The correction employs a modulation transfer function (MTF) of the detector deduced analytically based on an experimentally confirmed assumption about the origin of the anisotropy due to the asymmetry of the read-out process of the instrument's CCD camera. The ...

2005-05-12

45

Results from the photoemission spectroscopy beamline 2B1 at Pohang Light Source  

Energy Technology Data Exchange (ETDEWEB)

The results of photoemission spectroscopy using molybdenum and tantalum samples have been obtained from the new beamline 2B1 at Pohang Light Source. Beamline 2B1 is based on a spherical grating monochromator (SGM) which is equipped with five gratings. The photon energy range from 184 to 1100 eV was covered in this work using two gratings (Gratings 4 and 5). The photon energy resolution has been deduced from Ta Fermi-level spectra and 3d spectra of Mo.

1999-06-01

46

Quenched large deviations for random walk in a random environment  

CERN Document Server

We take the point of view of a particle performing random walk with bounded jumps on Z^d in a stationary and ergodic random environment. We prove the quenched large deviation principle (LDP) for the pair empirical measure of the environment Markov chain. By the contraction principle, we deduce the quenched LDP for the mean velocity of the particle and obtain a variational formula for the corresponding rate function. We propose an Ansatz for the minimizer of this formula. We verify this Ansatz for nearest-neighbor walks on Z. As a separate result, we give a probabilistic formula for the ergodic invariant density of the environment Markov chain in the case of ballistic random walk with bounded jumps on Z.

2008-01-01

47

Nuclear magnetic resonance on oriented XVTa and XXTa  

Energy Technology Data Exchange (ETDEWEB)

XVTa and XXTa nuclei were oriented at low temperature as dilute impurities in Fe. The magnetic hyperfine splitting frequencies = B sub(HF)/Ih of the XVTa and XXTa ground states have been measured to be 320.45(11) and 317.552(55) MHz by using the technique of NMR-ON. Taking the known hyperfine field of Y Ta in Fe, the magnetic moments have been deduced: ( XVTa, 7/2 ) =2.270(45) and ( XXTa, 7/2 ) =2.250(45) sub(N). These values of the magnetic moments are discussed in the framework of the rotational model.

1984-08-01

48

Modelling and measurement of radon diffusion through soil for application on mine tailings dams  

International Nuclear Information System (INIS)

The mine dumps that arise from the gold mining operations in South Africa are a potential source of high concentrations of radon (222"Rn). Studying the diffusion of radon and the emanation from the soil will help to deduce the radon flux from these dumps to identify the problem areas for rehabilitation. This study describes measurements of the emanation coefficient and the modelling of the depth profile of the radon activity concentration, which is compared to a depth profile that was measured on such a mine dump. Emanation coefficients ranging from 0.13 to 0.39 have been obtained.

2005-04-01

49

Local lattice structure, crystal field and energy level patterns in CsCdBr_3:Tm"3"+ crystals  

International Nuclear Information System (INIS)

In CsCdBr_3, Tm"3"+ substitutes for Cd"2"+. It predominately forms symmetric dimer centers and single-ion centers, both of trigonal symmetry. The energy level schemes of both centers were determined by EPR and site-selective laser spectroscopy. To describe the spectra term dependent crystal-field parameters were deduced on the basis of a microscopic model taking into account the local lattice deformation induced by the impurity centers and the quasi-resonant virtual scattering of intrinsic lattice excitations by the Tm"3"+ ions. (orig.)

1998-07-24

50

Laser photoelectron spectroscopy of ions. Progress report, August 1, 1982-July 31, 1983  

Energy Technology Data Exchange (ETDEWEB)

We have undertaken a program which measures the photoelectron spectra of negative-ion beams. This experiment has afforded us direct information about these ions and the corresponding neutral radicals. Several ions and numerous radicals are believed to be crucial intermediates in combustion processes and flame chemistry. We have fabricated a spectrometer which directly measures electron affinities (EA). Knowledge of the EA and gas-phase acidity of a radical has enabled us to deduce several radical heats of formation and bond strengths.

1983-03-01

51

Isospin mixing in the decay of the T/sub greater-than/ giant dipole state  

Energy Technology Data Exchange (ETDEWEB)

The magnitude of the isospin mixing in the decay of the T/sub greater-than/ giant dipole resonance has been estimated, using the (..gamma.., n) and (..gamma..,p) cross sections available for the medium-weight nuclei /sup 60/Ni, /sup 88/Sr, /sup 89/Y, /sup 90/Zr, and /sup 92/Mo. The deduced values show a fair correspondence with the existing data for mixing between compound states. From these results the mean mixing Coulomb matrix elements between compound states could also be derived.

1984-10-01

52

Ion Transport Measurements in a Multi-Dipole Argon Plasma by Broadband Laser Induced Fluorescence  

International Nuclear Information System (INIS)

Argon ion laser induced fluorescence measurements were carried out in a multipolar filament discharge with a broadband diode laser centered on 668 nm, which stimulated a transition from the metastable state in Ar(II) 3d4F7/2 to 4p4D05/2. The intensity of the induced fluorescence at 442 nm was maximized by the optimization of the discharge parameters and the laser power. From the recovery of the background fluorescence after the laser was turned off, the ion diffusion coefficient was deduced and compared with the result inferred from the experiments of ion acoustic wave (IAW) damping.

2009-06-01

53

Investigation of the "1"0"1Mo level and gamma-decay scheme by thermal neutron capture in "1"0"0Mo  

International Nuclear Information System (INIS)

The #gamma#-radiation following thermal neutron capture in "1"0"0Mo has been studied by singles and coincidence measurements. A "1"0"1Mo level scheme has been deduced and is compared with the results of previous (d,p), (n,#gamma#) and "1"0"1Nb decay studies. The existence of the first excited state at 13.51 keV has been confirmed. The present data yield a neutron binding energy of 5398.4 KeV. (Auth.).

1975-03-01

54

Interferometry and refraction measurements in plasmas of elliptical cross-section  

Energy Technology Data Exchange (ETDEWEB)

The measurement of electron densities using interferometry and refraction measurements in plasmas with cross-sections where the electron density contours are concentric ellipses is examined. Transforms are found for both interferometrically deduced optical path-length differences and refraction angle data obtained from elliptical cross-section plasmas. The transformed data can be inverted to give electron densities using standard techniques developed for circular cross-section plasmas. Refraction of light in elliptical cross-section plasmas is examined using numerical ray tracing.

1984-04-14

55

Exact solutions to the Chandrasekhar Page angular equation  

CERN Document Server

Exact solutions are found for the Chandrasekhar Page angular equation which results when the Dirac equation in a Kerr Newman space time is separated into its radial and angular parts. The solutions turn out to be remarkably simple in form while satisfying the asymptotic conditions deduced earlier. The eigenvalues are found to be the square root of the total angular momentum as first found by Dirac for flat space; supplemented by a term which is the product of the mass of the Dirac particle times the specific angular momentum of the black hole. The additional contribution is what is expected from frame dragging.

2006-01-01

56

Electron capture decay of sup 203 Pb  

Energy Technology Data Exchange (ETDEWEB)

Intensities of {gamma}-transitions emerging from the EC decay of {sup 203}Pb were measured precisely. The obtained relative {gamma}-intensities are 100%(279.2keV), 4.14+-0.08%(401.3keV) and 0.932+-0.022%(680.5keV). The 279.2 and 680.5keV level feeding {beta}-branching ratios were deduced to be 95.3+-0.1 and 4.7+-0.1% respectively. {sup 203}Pb is suggested for calibration purposes. (author).

1989-01-01

57

Comments on open-ended magnetic systems for fusion  

Energy Technology Data Exchange (ETDEWEB)

Differentiating characteristics of magnetic confinement systems having externally generated magnetic fields that are open'' are listed and discussed in the light of their several potential advantages for fusion power systems. It is pointed out that at this stage of fusion research high-Q'' (as deduced from long energy confinement times) is not necessarily the most relevant criterion by which to judge the potential of alternate fusion approaches for the economic generation of fusion power. An example is given of a hypothetical open-geometry fusion power system where low-Q operation is essential to meeting one of its main objectives (low neutron power flux).

1990-09-24

58

Bragg-curve spectroscopy detector  

Energy Technology Data Exchange (ETDEWEB)

In an ionization chamber with the electric field parallel to the particle trajectories, the time dependence of the anode signal contains all the information about the energy and the nuclear charge of the ionizing particle. By proper pulse shaping with a long and a short time constant the total ionization charge and the ionization charge integrated around the Bragg maximum, respectively, can be obtained. The former signal is proportional to the total energy, whereas the latter allows the nuclear charge to be deduced directly. An energy resolution of 0.4% and a Z resolution ..delta..Z/Z = 1/82 was achieved for 130 MeV /sup 32/S ions and argon-methane as the stopping medium.

1982-02-01

59

Atomic photoelectric effect near threshold edges  

Energy Technology Data Exchange (ETDEWEB)

Total photon attenuation coefficients near absorption edges are determined in certain suitable elements and compounds. Photoelectric cross sections for elements are deduced from these by subtracting the coherent and incoherent scattering cross sections as well as other elemental cross sections in the cases of compounds. Certain deviations are observed on comparison with the available theoretical and experimental compilations. The I/sub L//sub ..cap alpha..//Il x-ray intensity ratio measured by photon excitation near threshold is found to agree better with the theory than the other available experimental data.

1985-07-01

60

Atomic photoelectric effect near threshold edges  

International Nuclear Information System (INIS)

Total photon attenuation coefficients near absorption edges are determined in certain suitable elements and compounds. Photoelectric cross sections for elements are deduced from these by subtracting the coherent and incoherent scattering cross sections as well as other elemental cross sections in the cases of compounds. Certain deviations are observed on comparison with the available theoretical and experimental compilations. The I/sub L//sub #alpha#//Il x-ray intensity ratio measured by photon excitation near threshold is found to agree better with the theory than the other available experimental data.

1985-01-01

61

Alignment accuracy of focused ion beam implantation  

Energy Technology Data Exchange (ETDEWEB)

The theoretical alignment limit for focused ion beam (FIB) implantation was deduced from the calculated resolution for the detection of an alignment mark. The alignment resolution varies with the signal to noise ratio and there is an optimum current which gives the best resolution. The alignment resolution epsilon/sub sigma/ is approximately 0.006 ..mu..m for a 160 keV Si/sup ++/ beam from our FIB implanter. The measured alignment error is approximately 0.06 ..mu..m and the main reason of this discrepancy is vibration. The ultimate limit on the alignment error can be reached through improvements in the implanter system.

1987-06-01

62

Age determination of plutonium material in nuclear forensics by thermal ionisation mass spectrometry  

International Nuclear Information System (INIS)

Age is a key parameter when deducing the history of plutonium material, i.e. the plutonium produced in the nuclear reactors. This is of vital importance, when a smuggled plutonium sample has been seized and the origin has to be determined. A methodology is described which allows accurately to determine the age of plutonium material by thermal ionisation mass spectrometry using independent parent/daughter relations. This has been demonstrated for Reference Materials of known ages as well as for real samples. The already established method using gamma spectrometry is compared to this. (orig.)

2000-02-01

63

Acute gastric erosions in the rat. II. Viability of the gastric mucosa  

Energy Technology Data Exchange (ETDEWEB)

The autoradiographic appearance of the gastric mucosa, 5 hours after administration of indomethacin, was investigated in 29 adult rats. Indomethacin induced superficial gastric erosions. Autoradiography demonstrated the presence of viable gastric cells (as deduced by their ability to incorporate 3H-cytidin, an RNA precursor) not only in the mucosa without erosions, but also in the mucosa underneath the superficial erosions. The results indicate that indomethacin induced gastric erosions are not the superficial expression of a necrotic process taking place in the full thickness of the gastric mucosa at a particular site. A lumen-borne mechanism appears to be responsible for the formation of erosive areas in the mucosa.

1981-01-01

64

(/sup 3/He,n) reaction in the Aapprox. =100 region  

Energy Technology Data Exchange (ETDEWEB)

The available experimental data on the (/sup 3/He,n) reaction between the ground states of even-even nuclei and lowest 1/2/sup -/ levels of odd-A nuclei in the Aapprox.=100 region are analyzed in a systematic way by the DWBA. The deduced relative intensities of these two-proton transfers, and their uncertainties, are compared to the predictions of various nuclear models. In particular, the influence of the finite dimension of the configuration space available to the transferred protons, and of the blocking effect of a 2p1/2/sup -/ proton, are examined. (orig.).

1986-03-01

65

Steady-state isotopic transient kinetic analysis investigation of CO-O_2 and CO-NO reactions over a commercial automotive catalyst  

International Nuclear Information System (INIS)

In this paper, steady-state isotopic transient kinetic analysis (SSITKA) is used to study two model reactions, CO oxidation and CO-NO reactions, on a typical formulation of a three-way auto-catalyst. Under steady-state conditions, abrupt switches in the isotopic composition of CO ("1"2C"1"6O/"1"3C"1"8O) were carried out to produce isotopic transients in both labeled reactants and products. Along with the determination of the average surface lifetimes and concentrations of reaction intermediates, an analysis of the transient responses along the carbon reaction pathway indicated that the distribution of active sites for the formation of CO_2 was bimodal for both reactions. Furthermore, relatively few surface sites contributed to the overall reaction rate.

1991-08-25

66

Five naturally bioactive molecules including two rhamnopyranoside derivatives isolated from the Streptomyces sp. strain TN58  

British Library Electronic Table of Contents (United Kingdom)

Extraction of 25 L fermentation broth of the newly isolated Streptomyces sp. strain TN58 and various separation and purification steps led to the isolation of five bioactive metabolites, namely brevianamide F (C1), reported from a streptomycete for the first time, N?-acetyltryptamine (C2), thiazolidomycin (C3), and two rhamnopyranosides (C4 and C5). These two rhamnopyranosides were produced directly, without precursor addition. The chemical structure of these five active compounds was established on the basis of 1H, 13C/APT and 2D NMR spectra, ESI and EI-MS data, and by comparison with data from the literature. According to the biological studies, we show in this work that the compounds C1, C2, C4 and C5 possess antimicrobial activities.

2009-01-01

67

Experimental bovine trypanosomiasis. Changes in serum immunoglobulins, complement and complement components in infected animals.  

Science.gov (United States)

In three calves experimentally infected with Trypanosoma congolense the amounts of IgG1 and IgG2 were little changed and similar to those of normal animals. IgM increased in amount early in the infection and the amount of the increase appeared related to the parasite burden. The amounts of IgA and IgE were both much decreased and this also appeared related to the numbers of parasites in the blood. There was a decrease in the amounts of total haemolytic complement and complement components C1, C1q and C3 in the infected calves. Furthermore the amounts of properdin fluctuated with the cyclical changes in numbers of T. congolense parasites in the individual calves. No significant change in the amount of C8 was observed. It is considered that activation of both the alternative and the classical complement pathways occurs in trypanosome infected animals but that neither pathway goes to its terminal stages.

1978-11-01

68

Nonsyndromic bilateral and unilateral optic nerve aplasia: first familial occurrence and potential implication of CYP26A1 and CYP26C1 genes  

UK PubMed Central (United Kingdom)

PurposeOptic nerve aplasia (ONA, OMIM 165550) is a very rare unilateral or bilateral condition that leads to blindness in the affected eye, and is usually associated with other ocular...Full Text Available

69

Lack of the Long Pentraxin PTX3 Promotes Autoimmune Lung Disease but not Glomerulonephritis in Murine Systemic Lupus Erythematosus  

UK PubMed Central (United Kingdom)

The long pentraxin PTX3 has multiple roles in innate immunity. For example, PTX3 regulates C1q binding to pathogens and dead cells and regulates their uptake by phagocytes. It also inhibits P-selectin-mediated...Full Text Available

70

Decay of "1"7"7T_a composite nucleus. Comparison of excitation functions for the reaction residues occurring in "1"2C + "1"6"5H_0 and "1"4N + "1"6"3D_y reactions  

International Nuclear Information System (INIS)

The experimental has been performed with a view to studying complete and incomplete fusion in "1"4N + "1"6"3D_y system below 7 MeV/nucleon. The excitation functions for several reactions have been measured using the activation technique and compared with the theoretical predictions based on statistical models. The codes ALICE-91 and CASCADE used earlier for the analysis of excitation functions in case of "1"2C + "1"6"5H_0 system have been used here also with the same set of input parameters. It has been observed that the theoretical calculations do not match with the experimental excitation functions well but the overall shape of the excitation function is reproduced satisfactorily. The composite nucleus ("1"7"7T_a) formed in this ("1"4N + "1"6"3D_y) case is the same as the one formed in "1"2C + "1"6"5H_0 system studied earlier. Measured excitation functions for the same decay channels in the two cases ...

2002-10-01

71

38 CFR 4.71a - Schedule of ratings-musculoskeletal system.  

Science.gov (United States)

...prosthesis) Anatomical loss near hip (preventing use of prosthesis) Anatomical loss or loss of use below elbow M Codes M-1 a, b, or c, 38 CFR 3.350 (c)(1)(i) L Codes L-1 d, e, f, or g, 38 CFR 3.350(b)...

2010-07-01

72

g factors and lifetimes for 2_1"+ states of sup(84,86,88)Sr  

International Nuclear Information System (INIS)

The g factors of the 2_1"+ states in sup(84,86,88)Sr have been deduced using the thin-foil transient field technique with the field calibration of the Rutgers group. The values are g("8"4Sr)= + 0.419(47), g("8"6Sr)= + 0.273(50) and g("8"8Sr)= + 1.15(17). The mean lifetimes of the 2_1"+ states in sup(86,88)Sr were determined by the Doppler-shift attenuation method to be 2.10(22) ps and 0.219(23) ps respectively. The g factor and lifetime results are compared with shell model and interacting boson model predictions. (author).

73

X-ray magnetic form factor of UTe  

Energy Technology Data Exchange (ETDEWEB)

A measurement of the magnetic form factor of a ferromagnetic actinide compound of UTe with circularly polarized X-rays is reported. The present geometrical configuration of the measurement gives a form factor of L(k)+0.3S(k), where L(k) and S(k) are the form factors of the orbital and the spin magnetic moment, respectively. We have combined the X-ray magnetic form factor with the neutron one which gives L(k)+2S(k) (G. Busch et al.: J. Phys. C 12 (1979) 1391), and have deduced L(k) and S(k) separately. The obtained profiles of L(k) and S(k) show that the orbital and the spin magnetic moments are spatially spread out more than those calculated for a free uranium ion. (author).

1995-07-01

74

X-ray magnetic form factor of UTe  

International Nuclear Information System (INIS)

A measurement of the magnetic form factor of a ferromagnetic actinide compound of UTe with circularly polarized X-rays is reported. The present geometrical configuration of the measurement gives a form factor of L(k)+0.3S(k), where L(k) and S(k) are the form factors of the orbital and the spin magnetic moment, respectively. We have combined the X-ray magnetic form factor with the neutron one which gives L(k)+2S(k) (G. Busch et al.: J. Phys. C 12 (1979) 1391), and have deduced L(k) and S(k) separately. The obtained profiles of L(k) and S(k) show that the orbital and the spin magnetic moments are spatially spread out more than those calculated for a free uranium ion. (author).

75

Vacancy complex scattering mobility of holes in IR-photoexcited p-type ZnTe  

Energy Technology Data Exchange (ETDEWEB)

Conductivity and Hall effect measurements were made in dark and IR-photoexcited p-type ZnTe samples between 77 and 300 K. Acceptor vacancy complexes of activation energies 0.09-0.1 eV were found to be present in the photoexcited samples. Different possible scattering mobilities were considered for both samples to explain the observed hole mobility. In the photoexcited sample a scattering mobility due to vacancy complexes was suggested for the first time to explain the results. The scattering centres were associated with native vacancy complexes segregated at the dislocations sites. The expression for the complex scattering mobility has been deduced using the curve fitting method to be {mu}{sub C}=(6.6x10{sup -11})T{sup 5} e{sup 725/T}. (orig.).

1990-10-01

76

Total M shell X-ray production cross sections and average fluorescence yields in 11 elements from Tm to U at photon energy of 5.96 keV  

International Nuclear Information System (INIS)

Total M shell X-ray production cross section for 11 elements with 69 #<=# Z #<=# 92 have been measured using an incident photon energy of 5.96 keV. Measurements have been performed using an "5"5Fe annular source and a Si(Li) detector. Average M shell fluorescence yield at each incident photon energy has been deduced, using the experimental total M X-ray production cross section and theoretical M shell photoionization cross section. Present experimental results are compared with other experimental and theoretical values. Reasonable agreement (to within 0.3-28%) is typically obtained between present and other experimental and theoretical values.

2005-04-01

77

To Get Overall Shapes and New Data of the 120-Cell and the 600-Cell  

CERN Document Server

This research will be helpful for people to display the 2-dimensiona projective models of 4-variable actual problems in many fields, in order to investigate deeply those actual problems. By using the theory of N-dimensional finite rotation group of the regular polytopes, the author established the 2-dimensional projective model of 4-dimensional rectangular coordinate system, and deduced a transformation matrix, and adopt it to display successfully the 2-dimensional overall shapes of two most complicated regular polytopes 120-Cell and 600-Cell. In the meantime, the author calculated all the vertex coordinates and determine the joint relationships between adjacent vertices of the regular polytopes 120-Cell and 600-Cell. Also, this provided a pattern for displaying the 2-dimensional projective model of 4-variable actual problem.

2009-01-01

78

The electron cyclotron absorption diagnostic for the JET pumped divertor plasma  

International Nuclear Information System (INIS)

We present the design of a diagnostic system to measure electron cyclotron absorption at the second harmonic E-mode resonance in the JET pumped divertor plasma. The diagnostic will measure transmission as a function of frequency along one or more sightlines from which the spatial profile of the n_eT_e product will be deduced. The divertor is briefly described, and the electron cyclotron resonance physics relevant to this measurement is reviewed. The problems of measuring transmission using an oversized transmission system are discussed and the chosen measurement technique, a swept frequency interferometer using a coherent radiation source, is described. A prototype of the instrument has been assembled to test the measurement technique. Some data demonstrating the instrument's characteristics are presented. The nonresonant losses, which may affect the interpretation of the measurement, are also discussed. (orig.).

1993-03-01

79

System and method for non-destructive evaluation of surface characteristics of a magnetic material  

Energy Technology Data Exchange (ETDEWEB)

A system and a related method for non-destructive evaluation of the surface characteristics of a magnetic material. The sample is excited by an alternating magnetic field. The field frequency, amplitude and offset are controlled according to a predetermined protocol. The Barkhausen response of the sample is detected for the various fields and offsets and is analyzed. The system produces information relating to the frequency content, the amplitude content, the average or RMS energy content, as well as count rate information, for each of the Barkhausen responses at each of the excitation levels applied during the protocol. That information provides a contiguous body of data, heretofore unavailable, which can be analyzed to deduce information about the surface characteristics of the material at various depths below the surface.

1994-05-17

80

Studies of the low-lying levels in /sup 192/Pt and /sup 192/Os  

Energy Technology Data Exchange (ETDEWEB)

The energy level schemes of /sup 192/Os and /sup 192/Pt have been established on the basis of ..gamma..-..gamma.. coincidence studies using a dual parameter data collection system. Ge(Li) detectors were employed to study the gamma spectra produced in the E.C. and ..beta../sup -/ decays of /sup 192/Ir to /sup 192/Os and /sup 192/Pt, respectively. Thirteen new transitions and three new levels at 1146.95, 1237.35 and 1913.76 keV are suggested. Relative intensities from singles measurements, branching ratios, ..cap alpha..(K) and log ft values were calculated and multipolarities, spins and parities deduced. Comparisons are made with predictions of the Interacting Boson Model calculated on the basis of an O(6) to SU(3) transition.

1985-02-01

81

Studies of the low-lying levels in "1"9"2Pt and "1"9"2Os  

International Nuclear Information System (INIS)

The energy level schemes of "1"9"2Os and "1"9"2Pt have been established on the basis of #gamma#-#gamma# coincidence studies using a dual parameter data collection system. Ge(Li) detectors were employed to study the gamma spectra produced in the E.C. and #beta#"- decays of "1"9"2Ir to "1"9"2Os and "1"9"2Pt, respectively. Thirteen new transitions and three new levels at 1,146.95, 1,237.35 and 1,913.76 keV are suggested. Relative intensities from singles measurements, branching ratios, #alpha#(K) and log ft values were calculated and multipolarities, spins and parities deduced. Comparisons are made with predictions of the Interacting Boson Model calculated on the basis of an O(6) to SU(3) transition. (orig.).

1985-01-01

82

Research of time-domain equivalent circuit method in solving dispersion of coupled-cavity traveling-wave tube  

International Nuclear Information System (INIS)

In this paper, a time-domain equivalent circuit method is applied to solve dispersion of coupled-cavity travelling-wave tube (CCTWT). First, the time-domain circuit equations of CCTWT coupled-cavity chain are deduced from the equivalent circuit model. Then, the equations are solved numerically by fourth-order Runge-Kutta method and a program CTTDCP is developed using MATLAB. Last, a L-band CCTWT is calculated using CTTDCP and the cavity pass-band of this tube is computed to be 1.08-1.48 GHz, which is consistent with the experimental results and the simulation results of electromagnetic code and demonstrates the validity of the time-domain equivalent circuit method. In addition, a new design method which uses the equivalent circuit method and electromagnetic simulation together to optimize the cold cavity characteristics of CCTWT is proposed. (authors)

2008-09-01

83

Reinforced concrete beam-column joints with crossed inclined bars under cyclic deformations  

British Library Electronic Table of Contents (United Kingdom)

This experimental study investigates the effectiveness of crossed inclined bars (X-bars) as joint shear reinforcement in exterior reinforced concrete beam-column connections under cyclic deformations. Test results of 20 joint subassemblages with various reinforcement ratios and arrangements including X-bars in the joint area are presented. The X-type, non-conventional reinforcement is examined as the only joint reinforcement and in combination with common stirrups or vertical bars. The experimental results reported herein include full loading cycle curves, energy dissipation values and a categorization of the observed damage modes. Based on the comparisons between the overall hysteretic responses of the tested specimens, it is deduced that joints with X-bars exhibited enhanced cyclic perfo...

2008-01-01

84

Primary results of measuring plasma electron temperature with YAG laser thomson scattering system on the HL-2A tokamak  

International Nuclear Information System (INIS)

This article describes the laser Thomson scattering principle and the developed system on HL-2A device. The high power Q-switch Nd:YAG laser, with a wavelength of 1064 nm, can sufficiently satisfy the measurement requirement. The polycromator consisting of avalanche photo-diodes(APD) and narrow band interference filters, can effectively improve the measurement of scattering light. The electron temperature is deduced by error-weighted lookup table method, which improves the data- processing speed or efficiency. Finally, the experiment results of the one-point electron temperature during different discharges of plasma are presented. (authors)

2008-07-01

85

Preparation and photocatalytic property of pyrochlore Bi2Ti2O7 and (Bi, La) 2Ti2O7 films  

British Library Electronic Table of Contents (United Kingdom)

Dopant-free Bi2Ti2O7 thin films with pyrochlore structure and La-doped bismuth titanate thin films have been fabricated by means of chemical solution decomposition, and characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy and UV?Vis spectrophotometry in this study. Their photocatalytic activities have been evaluated by photodegrading methyl orange solution, and the optimum processing parameters for the highest photocatalytic activity have been found. Moreover, the effects of La-doping on the phase transformation and the photocalalytic activity have been studied. It has been deduced from the experiment result that substituted La3+ ions can act as a stabilizer of Aurivillus phase BLT and a grain?growth inhibitor in BLT thin films.

2008-01-01

86

Plastic wastes, lube oils and carbochemical products as secondary feedstocks for blast-furnace coke production  

British Library Electronic Table of Contents (United Kingdom)

Two plastic wastes (polyolefin-enriched and multicomponent), two lube oils (paraffinic and synthetic) and one coal-tar were assessed as individual and combined additives to coal blends for the production of blast furnace coke. The effects of adding 2wt.% of these additives or their mixtures (50:50 w/w) on the coking capacity of coal, coking pressure and coke quality parameters were investigated. It was found that the two plastic wastes reduce fluidity, whereas the addition of oils and tar helps to partially restore the fluidity of the coal-plastic blend. From the co-carbonization of the coking blend with the different wastes in a movable wall oven of over 15kg capacity, it was deduced that polyolefins have a detrimental effect on coking pressure. The addition of oils and tar to the coal-pl...

2011-01-01

87

Plasma density ramp for relativistic self-focusing of an intense laser  

International Nuclear Information System (INIS)

It is known that a high-power laser propagating through an underdense plasma can acquire a minimum spot size due to relativistic self-focusing. Beyond the focus, the nonlinear refraction starts weakening, and the spot size of the laser increases, showing periodic self-focusing/ defocusing behavior with the distance of propagation. To overcome the defocusing, we propose the introduction of a localized upward plasma density ramp. In the presence of an upward ramp of plasma density, the laser beam obtains a minimum spot size and maintains it with only a mild ripple. For suitable parameters of the laser and the plasma, we have deduced conditions for the self-focusing. This kind of plasma density ramp may be observed in a gas-jet plasma experiment and resembles a plasma lens.

2007-05-01

88

Photo-emission-electron-microscopy for characterization of an operating organic electronic device  

Energy Technology Data Exchange (ETDEWEB)

Photoemission-electron-microscopy (PEEM) is introduced as a tool for the characterization of organic electronic devices. PEEM-measurements are used for imaging as well as for spectroscopic analyses by illumination with light of a Hg-lamp (4.9 eV), a D2 lamp (7.3 eV), and with synchrotron radiation for resonant photoelectron spectroscopy. We determine the charge carrier concentration inside the channel region of the organic device and its lateral distribution. From resonant photoelectron spectroscopy (RPES) we deduce the electronic states which are accessible with the Hg and D2 illumination. Photoelectron-spectroscopy at selected areas ({mu}-PES) gives information on the absolute values of surface potentials in lateral resolution. We are able to perform these studies with applied voltages at the source- and drain-electrode.

2006-01-20

89

PDBpaint, a visualization webservice to tag protein structures with sequence annotations  

British Library Electronic Table of Contents (United Kingdom)

Summary: Protein features are often displayed along the linear sequence of amino acids that make up that protein, but in reality these features occupy a position in the folded proteins 3D space. Mapping sequence features to known or predicted protein structures is useful when trying to deduce the function of those features and when evaluating sequence or structural predictions. To facilitate this goal, we developed PDBpaint, a simple tool that displays protein sequence features gathered from bioinformatics resources on top of protein structures, which are displayed in an interactive window (using the Jmol Java viewer). PDBpaint can be used either with existing protein structures or with novel structures provided by the user. The current version of PDBpaint allows the visualization of annot...

2011-01-01

90

Origin determination of plutonium material in nuclear forensics  

International Nuclear Information System (INIS)

Plutonium, seized from illicit trafficking in nuclear materials, can originate from several, distinct sources. The primary focus of nuclear-forensics investigations of confiscated Pu is to specify correctly its origin. Such specification is possible by means of accurate determination the Pu isotopic composition. Five Pu samples of different origins were analysed by thermal-ionisation mass spectrometry. The source (i.e., the type of production reactor) of each sample was determined by comparing the measured Pu isotopic composition with that calculated by one of two reactor-production computer codes, ORIGEN2 and SCALE. These results, in conjunction with the age determination of each sample, allow us to deduce the origin of each. (author)

2000-11-01

91

Optical-Model Description of Time-Reversal Violation  

CERN Document Server

A time-reversal-violating spin-correlation coefficient in the total cross section for polarized neutrons incident on a tensor rank-2 polarized target is calculated by assuming a time-reversal-noninvariant, parity-conserving ``five-fold" interaction in the neutron-nucleus optical potential. Results are presented for the system $n + {^{165}{\\rm Ho}}$ for neutron incident energies covering the range 1--20 MeV. From existing experimental bounds, a strength of $2 \\pm 10$ keV is deduced for the real and imaginary parts of the five-fold term, which implies an upper bound of order $10^{-4}$ on the relative $T$-odd strength when compared to the central real optical potential.

1994-01-01

92

On the electrodynamics of tachyons  

International Nuclear Information System (INIS)

Electrodynamic properties of processes involving charged tachyons are considered in connection with the real superluminal Lorentz transformations. These transformations are interpreted without making use of a tachon corridor and so that the interaction of tachyons from subluminal sources with ordinary matter is Lorentz invariant. Transformations of the electromagnetic fields are deduced from the extended principle of relativity. They are necessary in order to obtain the field equations that are satisfied by fields obeying Maxwell equations relative to superluminal inertial frames with respect to subluminal inertial frames. The field equations allow one to get the dependence of the field energy density and its current on the field strengths. The resulting equations are applied in a discussion of plane electromegnetic waves, sent out by a superluminal source. The obtained electrodynamics allows the existence of charged tatric charges do not behave as magnetic ...

93

On parameter derivatives of the associated Legendre function of the first kind (with applications to the construction of the associated Legendre function of the second kind of integer degree and order)  

British Library Electronic Table of Contents (United Kingdom)

A relationship between partial derivatives of the associated Legendre function of the first kind with respect to its degree, Formula Not Shown , and to its order, Formula Not Shown , is established for Formula Not Shown . This relationship is used to deduce four new closed-form representations of Formula Not Shown from those found recently for Formula Not Shown by the author [R. Szmytkowski, On the derivative of the associated Legendre function of the first kind of integer degree with respect to its order (with applications to the construction of the associated Legendre function of the second kind of integer degree and order), J. Math. Chem. 46 (2009) 231]. Several new expressions for the associated Legendre function of the second kind of integer degree and order, Formula Not Shown , suita...

2012-01-01

94

Off-shell Interactions for closed-string tachyons  

Energy Technology Data Exchange (ETDEWEB)

Off-shell interactions for localized closed-string tachyons in C/Z{sub N} superstring backgrounds are analyzed and a conjecture for the effective height of the tachyon potential is elaborated. At large N, some of the relevant tachyons are nearly massless and their interactions can be deduced from the S-matrix. The cubic interactions between these tachyons and the massless fields are computed in a closed form using orbifold CFT techniques. The cubic interaction between nearly-massless tachyons with different charges is shown to vanish and thus condensation of one tachyon does not source the others. It is shown that to leading order in N, the quartic contact interaction vanishes and the massless exchanges completely account for the four point scattering amplitude. This indicates that it is necessary to go beyond quartic interactions or to include other fields to test the conjecture for the height of the tachyon potential. (author)

2004-05-01

95

Off-Shell Interactions of Closed-String Tachyons  

Energy Technology Data Exchange (ETDEWEB)

Off-shell interactions for localized closed-string tachyons in C/Z{sub N} superstring backgrounds are analyzed and a conjecture for the effective height of the tachyon potential is elaborated. At large N, some of the relevant tachyons are nearly massless and their interactions can be deduced from the S-matrix. The cubic interactions between these tachyons and the massless fields are computed in a closed form using orbifold CFT techniques. The cubic interaction between nearly-massless tachyons with different charges is shown to vanish and thus condensation of one tachyon does not source the others. It is shown that to leading order in N, the quartic contact interaction vanishes and the massless exchanges completely account for the four point scattering amplitude. This indicates that it is necessary to go beyond quartic interactions or to include other fields to test the conjecture for the height of the tachyon potential.

2004-04-07

96

Numerical solutions of high-frequency perturbations in Bianchi type IX models  

International Nuclear Information System (INIS)

The problem in perturbation theory in general relativity is finding a natural gauge which simplifies the equations considerably. We solved the first and second order perturbation equations in the ''Lorentz gauge'' using the two-timing method. The equations were deduced from the equations of Einstein in the presence of a matter energy-momentum tensor of a perfect fluid with equation of state p = (#gamma#-1) rho. It is found that the 0--0 component of the first order equations together with the gauge conditions are consistent with the Bianchi type V model, without axial symmetry. It represents a ''ground state'' situation of the Bianchi type IX model (Mixmaster model.) The second order equations, describing the reaction back of the gravitational waves on the slowly varying background, give rise to rotation and will disturb the isotropization mechanism. The numerical solutions show all the features which are expected to appear. Moreover, it is found that the frequency ...

97

Numerical investigation of the impact of gas and cooling flow configurations on current and water distributions in a polymer membrane fuel cell through a pseudo-two-dimensional diphasic model  

British Library Electronic Table of Contents (United Kingdom)

For optimal performances, proton exchange membrane fuel cells require fine water and thermal management. Accurate modelling of the physical phenomena occurring in the fuel cell is a key issue to improve fuel cell technology. Here, an analytic steady state diphasic 2D model of heat and mass transfer is presented. Through this model, the aim of this work is to study the influence of local events on the global performances of a fuel cell. A part of the complete model is a microscopic representation of the coupling between water transport and charge transfers in the electrodes. The thickness of the liquid layer around the reactive agglomerates is deduced from the saturation. The evolution of the quantity of water within the catalyst layer is monitored and its influence on the global performanc...

2010-01-01

98

Nuclear structure studies via neutron interactions  

Energy Technology Data Exchange (ETDEWEB)

Research preformed consisted of: (1) publication of an experimental paper for the n + {sup 40}Ar high resolution total cross section and submission of a theoretical paper dealing with the prediction of the average parameters deduced from the the data; (2) preliminary R-matrix analysis of the neutron total cross section data for the n + {sup 208}Pb systems, up to an energy of 1.7 MeV; (3) completed the analysis of neutron total cross section of data for n + {sup 54}Fe up to energy of 500 keV, with j{sup {pi}} values confirmed, in most cases, by differential scattering data; (4) analysis of total cross section data for the n + {sup 88}Sr system up to an energy of 175 keV; (5) development of a graphical interface for the code RFUNC, used to calculate the differential scattering cross sections, for comparison with measurements.

1991-03-01

99

Nuclear magnetic resonance on oriented "1"7"5Ta and "1"7"7Ta  

International Nuclear Information System (INIS)

"1"7"5Ta and "1"7"7Ta nuclei were oriented at low temperature as dilute impurities in Fe. The magnetic hyperfine splitting frequencies #nu#="+#mu#B sub(HF)/Ih"+ of the "1"7"5Ta and "1"7"7Ta ground states have been measured to be 320.45(11) and 317.552(55) MHz by using the technique of NMR-ON. Taking the known hyperfine field of "1"8"1Ta in Fe, the magneticmoments have been deduced: "+#mu#("1"7"5Ta, 7/2"+)"+=2.270(45) and "+#mu#("1"7"7Ta, 7/2"+)"+=2.250(45)#mu# sub(N). These values of the magnetic moments are discussed in the framework of the rotational model. (author).

100

Momentum transfer in 30-200 MeV/sup 4/He induced reaction with /sup 59/Co  

Energy Technology Data Exchange (ETDEWEB)

Thick-target recoil ranges of radioactive nuclei produced in 30-200 MeV alpha-particle bombardment of /sup 59/Co have been used to deduce the longitudinal momentum transfer per projectile nucleon (psub(parallel)/A) as a function of residue mass and bombarding energy. The average value of psub(parallel)/A increases monotonically with bombarding energy and reaches a maximum value of proportional160 MeV/c at proportional23 MeV/u, and decreases thereafter. The maximum value of psub(parallel)/A is equal to the incident momentum up to proportional23 MeV/u and saturates at a value of proportional220 MeV/c beyond this energy.

1984-03-01

101

Memory of multiple aging stages above the freezing temperature in the Relaxor ferroelectric PLZT.  

Science.gov (United States)

The dynamic dielectric susceptibility and the elastic compliance of the relaxor ferroelectric lanthanum lead zirconate titanate (PLZT) 9/65/35 have been measured under different cooling and heating protocols in order to study aging and memory. The memory of multiple aging stages at different temperatures has been found (several dips in the susceptibility curves on heating), as in spin glass systems below the glass transition. Remarkably, in PLZT the memory of several aging stages is retained also above the freezing temperature deduced from the dynamic susceptibilities. The results are discussed in light of the existing models of aging and memory in spin and dipolar glasses. PMID:15447139

2004-08-24

102

Magnetic properties of B and AB-spinels Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Ni, Mg) materials  

Energy Technology Data Exchange (ETDEWEB)

The magnetic properties of diluted spinels Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Mg, Ni) systems have been studied by mean field theory, probability law and high-temperature series expansions method in the range 0 {<=} x {<=} 1. The exchange interactions are calculated by the first and second theory, respectively. The magnetic phase diagrams of Zn{sub 1-x}M{sub x}Fe{sub 2}O{sub 4} (M = Mg, Ni) are calculated by the high-temperature series expansions, combined with the Pade approximants method. The critical exponent associated with the magnetic susceptibility ({gamma}) is deduced.

2010-08-06

103

Low-lying states of {sup 109}Sn from the {sup 106}Cd({alpha},n{gamma}) reaction  

Energy Technology Data Exchange (ETDEWEB)

Measurements of {gamma}-ray, {gamma}{gamma}-coincidence and internal conversion electron spectra from the {sup 106}Cd({alpha},n{gamma}){sup 109}Sn reaction were carried out at 15-20 MeV {alpha}-particle bombarding energies with Ge(HP) {gamma}-ray and superconducting magnetic lens plus Si(Li) electron spectrometers. The energies, relative intensities, internal conversion coefficients and coincidence relations of the {sup 109}Sn transitions were determined, and a more complete, consistent level scheme has been deduced. Spin and parity values have been determined from the internal conversion coefficients, the bombarding-energy dependence of the side-feeding intensities of the states and the available {gamma}-ray angular distribution data. The level scheme was interpreted in the framework of the quasi-particle shell model.

1999-02-01

104

Local lattice structure, crystal field and energy level patterns in CsCdBr{sub 3}:Tm{sup 3+} crystals  

Energy Technology Data Exchange (ETDEWEB)

In CsCdBr{sub 3}, Tm{sup 3+} substitutes for Cd{sup 2+}. It predominately forms symmetric dimer centers and single-ion centers, both of trigonal symmetry. The energy level schemes of both centers were determined by EPR and site-selective laser spectroscopy. To describe the spectra term dependent crystal-field parameters were deduced on the basis of a microscopic model taking into account the local lattice deformation induced by the impurity centers and the quasi-resonant virtual scattering of intrinsic lattice excitations by the Tm{sup 3+} ions. (orig.) 22 refs.

1998-07-24

105

Levels in sup 152 Gd and sup 152 Sm populated by the decay of sup 152 Eu  

Energy Technology Data Exchange (ETDEWEB)

The energy level schemes of {sup 152}Gd and {sup 152}Sm have been established on the basis of single gamma-spectra, and gamma-gamma coincidence measurements. Ge(Li) detectors were used to study the gamma spectra produced in the EC/beta{sup +} and beta{sup -} decays of {sup 152}Eu to {sup 152}Sm and {sup 152}Gd, respectively. Thirteen new transitions are reported and data from eleven coincidence gates enabled five new levels to be suggested. Relative intensities and log ft values were calculated and spin/parities deduced. Comparisons are made with new predictions of the Interacting Boson Model. (orig.).

1990-01-01

106

Levels in "1"5"2Gd and "1"5"2Sm populated by the decay of "1"5"2Eu  

International Nuclear Information System (INIS)

The energy level schemes of "1"5"2Gd and "1"5"2Sm have been established on the basis of single #gamma#-spectra, and #gamma#-#gamma# coincidence measurements. Ge(Li) detectors were used to study the gamma spectra produced in the EC/#beta#"+ and #beta#"- decays of "1"5"2Eu to "1"5"2Sm and "1"5"2Gd, respectively. Thirteen new transitions are reported and data from eleven coincidence gates enabled five new levels to be suggested. Relative intensities and log ft values were calculated and spin/parities deduced. Comparisons are made with new predictions of the Interacting Boson Model. (orig.).

1990-01-01

107

Ion temperature anisotropy in high power helium neutral beam fuelling experiments in JET  

Energy Technology Data Exchange (ETDEWEB)

During helium beam fuelling experiments in JET, distinctive anisotropic features have been observed in the velocity distribution function describing both fast and thermal alpha particle populations. During the initial fuelling phase the central helium ion temperature observed perpendicular to the magnetic field is higher than the central electron temperature, while the central helium ion temperature observed parallel to the magnetic field is lower than or equal to the central electron temperature. In order to verify temperature measurements of both perpendicular and parallel lines of sight, other independent methods of deducing the ion temperature are investigated: deuterium ion temperature, deuterium density, comparison with neutron rates and profiles (influence of a possible metastable population of helium). 6 refs., 7 figs.

1994-07-01

108

Introduction to Big Bang nucleosynthesis: open and closed models, anisotropies  

Energy Technology Data Exchange (ETDEWEB)

A variety of observations suggest that the Universe had a hot dense origin and that the pregalactic composition of the Universe was determined by nuclear reactions that occurred in the first few minutes. There is no unique hot Big Bang theory, but the simplest version produces a primeval chemical composition that is in good qualitative agreement with the abundances deduced from observation. Whether or not any Big Bang theory will provide quantitative agreement with observations depends on a variety of factors in elementary particle physics (number and masses of stable or long-lived particles, half-life of neutron, structure of grand unified theories) and from observational astronomy (present mean baryon density of the Universe, the Hubble constant and deceleration parameter). The influence of these factors on the abundances is discussed, as is the effect of departures from homogeneity and isotropy in the early Universe.

1982-10-15

109

Identification and characterization of retinoid-active short-chain dehydrogenases/reductases in Drosophila melanogaster  

British Library Electronic Table of Contents (United Kingdom)

Background In chordates, retinoid metabolism is an important target of short-chain dehydrogenases/reductases (SDRs). It is not known whether SDRs play a role in retinoid metabolism of protostomes, such as Drosophila melanogaster. Methods Drosophila genome was searched for genes encoding proteins with ?50% identity to human retinol dehydrogenase 12 (RDH12). The corresponding proteins were expressed in Sf9 cells and biochemically characterized. Their phylogenetic relationships were analyzed using PHYLIP software. Results A total of six Drosophila SDR genes were identified. Five of these genes are clustered on chromosome 2 and one is located on chromosome X. The deduced proteins are 300 to 406 amino acids long and are associated with microsomal membranes. They recognize all-trans-retinaldehyd...

2009-01-01

110

Hot dip galvanised dual phase steels for automotive applications  

Energy Technology Data Exchange (ETDEWEB)

The automotive industry desires to optimize safety and lightweight construction for the production of cars and trucks. The resulting task for steel suppliers is to make steel grades available that can fulfil these requirements. Different projects have shown optimistic outlooks for optimization of safety and reduction of the weight of automobile bodies by using different high strength and ultra high strength steels. In the last group the dual phase steels play the lead. In recent years different steel grades have been developed and optimized for these applications. On one hand developing the mechanical properties as well as joining and forming of dual phase steels is one of the first steps. On the other hand different coated surfaces for various applications of dual phase steels is another step. Starting with characteristic production conditions for cold rolled hot dip galvanised dual phase steels, the mechanical properties for joining and forming will be deduced ...

2005-07-01

111

Highly excited spin-1 states in "8"8Sr by the (#gamma#,#gamma#) reaction  

International Nuclear Information System (INIS)

The resonant scattering of bremsstrahlung #gamma#-rays by a SrCO_3 target has been studied for #gamma#-ray energies of 5-11 MeV. Six #gamma#-transitions of energies between 6-8 MeV, which indicate six resonant states in "8"8Sr, were observed. The relative intensities of the resonantly scattered #gamma#-rays at 125 and 150"0 were found to be compatible only with the assignment of spin 1 to the six states. Radiative widths of the resonant states were deduced. The possibility that these states are components of the giant M1 resonance in "8"8Sr is discussed. (orig.).

112

Generation and relaxation of microstrains in GaN nanocrystals under extreme pressures  

International Nuclear Information System (INIS)

Nanocrystalline powders of GaN with grain sizes ranging from 2 to 30 nm were examined under high external pressures by in situ diffraction techniques in a diamond anvil cell at DESY (HASYLAB, Station F3). The experiments on densification of pure powders under high pressure were performed without a pressure medium. The mechanism of generation and relaxation of internal strains and their distribution in nanoparticles was deduced from Bragg reflections recorded in situ under high pressures at room temperature. The microstrain was calculated from the full-width at half-maximum (FWHM) values of the Bragg lines. It was found that microstrains in GaN crystallites are generated and subsequently relaxed by two mechanisms: generation of stacking faults and change of the size and shape of the grains occurring under external stress. (author)

2001-09-23

113

G factors and lifetimes for 2/sub 1//sup +/ states of sup(84,86,88)Sr  

Energy Technology Data Exchange (ETDEWEB)

The g factors of the 2/sub 1//sup +/ states in sup(84,86,88)Sr have been deduced using the thin-foil transient field technique with the field calibration of the Rutgers group. The values are g(/sup 84/Sr)= + 0.419(47), g(/sup 86/Sr)= + 0.273(50) and g(/sup 88/Sr)= + 1.15(17). The mean lifetimes of the 2/sub 1//sup +/ states in sup(86,88)Sr were determined by the Doppler-shift attenuation method to be 2.10(22) ps and 0.219(23) ps respectively. The g factor and lifetime results are compared with shell model and interacting boson model predictions.

1988-01-01

114

Effects of sawtooth crashes on beam ions and fusion product tritons in JET  

Energy Technology Data Exchange (ETDEWEB)

The effect of a sawtooth crash on the radial distribution of the slowing down fusion product tritons and on beams ions, is examined with measurements of the 2.5 MeV and 14 MeV neutron emission line-integrals before and after sawtooth crashes. In deuterium discharges, the 14 MeV neutron production was wholly attributable to burnup of the 1 MeV fusion product tritons from d-d fusion. The local emissivity of 14 MeV neutrons, and hence of the profile of thermalizing tritons, is shown to be only weakly affected by crashes in the discharges studied. This is in contradiction with the apparent behaviour of injected beam ions as deduced from a study of the considerable changes in local emissivity of the 2.5 MeV neutrons. Nevertheless, the behaviour of the fusion product tritons is consistent with the scaling of the beam injected deuterium. 1 ref., 6 figs.

1994-07-01

115

Density measurements of coal samples by different probe gases and their interrelation  

Energy Technology Data Exchange (ETDEWEB)

Density is useful in deducing the spatial structure of coals. In this paper, nitrogen has been used instead of the commonly employed helium, for the gas displacement pycnometer based density determination of a number of coals of Indian origin. The results show that the nitrogen-based densities are always higher than the helium-based ones. Also, empirical relationships between the helium-based and nitrogen-based coal densities have been developed by two modeling methods, namely, multi-variable regression and artificial neural networks. Although the two models have fared well, the neural network model exhibits a relatively better prediction accuracy and generalization performance than the regression model. This study thus demonstrates that nitrogen, which is cheaper and easily available, can be used gainfully as the probe gas for estimating the true density of coals. 23 refs., 1 fig., 3 tabs.

2007-07-15

116

Decays of "8"8Kr and "8"8Rb  

International Nuclear Information System (INIS)

The #gamma# rays following the #beta# decays of "8"8Kr and "8"8Rb have been studied, using both large volume Ge(Li) detectors for singles and coincidence measurements and anti-Compton spectrometry for singles measurements. Level schemes for "8"8Rb and "8"8Sr were constructed from the data and 74 of 81 #gamma# rays observed in the decay of "8"8Kr were placed in the "8"8Rb level scheme with 23 excited states. For the decay of "8"8Rb, all of the observed 27 #gamma# rays have been placed in the (well known) level structure of "8"8Sr. Spin and parity assignments have been deduced from #beta#-decay logft values and #gamma#-ray transition patterns. Possible shell model interpretations are presented for the level schemes.

117

Correction factors determination in large samples gamma assay using its own multi-gamma lines spectrum  

Energy Technology Data Exchange (ETDEWEB)

An easy and simple method for gamma assay of large multi-gamma lines samples was introduced in this work. This method performs the assay using point source calibration. The correction factors for volume and self-attenuation are experimentally deduced from the spectra of different thicknesses samples utilizing the following two simple well known facts: large and small samples of the same homogenous material have identical specific activities; the self-attenuation of gamma line decreases as its energy increases. The method was successfully applied to naturally occurring radioactive material (NORM) large samples. This method does not require complicated mathematical procedures. Neither sample matrix data nor detector unit composition is needed.

2009-10-15

118

Correction factors determination in large samples gamma assay using its own multi-gamma lines spectrum  

International Nuclear Information System (INIS)

An easy and simple method for gamma assay of large multi-gamma lines samples was introduced in this work. This method performs the assay using point source calibration. The correction factors for volume and self-attenuation are experimentally deduced from the spectra of different thicknesses samples utilizing the following two simple well known facts: large and small samples of the same homogenous material have identical specific activities; the self-attenuation of gamma line decreases as its energy increases. The method was successfully applied to naturally occurring radioactive material (NORM) large samples. This method does not require complicated mathematical procedures. Neither sample matrix data nor detector unit composition is needed.

2009-10-01

119

Correction factors determination in large samples gamma assay using its own multi gamma lines spectrum  

International Nuclear Information System (INIS)

An easy and simple method for gamma assay of large multi gamma lines samples was introduced in this work. This method performs the assay using point source calibration. The correction factors for volume and self-attenuation are experimentally deduced from the spectra of different thicknesses samples utilizing the following tow simple well known facts: Large and small samples of the same homogenous material have identical activities; the self attenuation of gamma line decreases as its energy increases. The method was successfully applied to NORM (Naturally Occurring Radioactive Material) large samples. This method doesn't require complicated mathematical procedures. Neither sample matrix data nor detector unit composition is needed. (author)

120

Cloning of the cDNA and gene for a human D sub 2 dopamine receptor  

Energy Technology Data Exchange (ETDEWEB)

A clone encoding a human D{sub 2} dopamine receptor was isolated from a pituitary cDNA library and sequenced. The deduced protein sequence is 96% identical with that of the cloned rat receptor with one major difference: the human receptor contains an additional 29 amino acids in its putative third cytoplasmic loop. Southern blotting demonstrated the presence of only one human D{sub 2} receptor gene. Two overlapping phage containing the gene were isolated and characterized. DNA sequence analysis of these clones showed that the coding sequence is interrupted by six introns and that the additional amino acids present in the human pituitary receptor are encoded by a single exon of 87 base pairs. The involvement of this sequence in alternative splicing and its biological significance are discussed.

1989-12-01

121

Bandgap properties of the indium sulfide thin-films grown by co-evaporation  

British Library Electronic Table of Contents (United Kingdom)

In the present study the optical properties of co-evaporated indium sulfide thin films are investigated. Before being optically characterized, the composition as well as the crystalline properties of the film have been checked with the help of energy dispersive spectroscopy (EDX) and X-Ray diffraction (XRD) analyses. The optical absorption coefficient ? of this indium sulfide film has been deduced from reflectivity R(?) and transmission T(?) measurements. The fit of the curve representing ?(h?) suggests that the ?-In2S3 has an indirect bandgap of 2.01?eV. Density functional theory (DFT) calculations are performed on this indium sulfide compound, using TB-LMTO code. Through these band structure investigations, an indirect bandgap is predicted as observed experimentally. The top of the valen...

2009-01-01

122

Alpha energy distribution as a probe for the feeding of ND and SD bands in {sup 151,152}Dy nuclei  

Energy Technology Data Exchange (ETDEWEB)

The study of the {alpha}-particle energy distributions associated with ND and SD states in {sup 151,152}Dy has been carried out. The Dy isotopes were produced in the reaction {sup 37}Cl+{sup 123}Sb at 191 MeV via the ({alpha}5n) and ({alpha}4n) channels, respectively. In {sup 151}Dy the {alpha}-particle energy distributions associated to ND and SD are very different from each other, both at the low and high energy sides inducing a difference of 3 MeV in the {alpha}-particle mean energy. In {sup 152}Dy the situation is different; the {alpha}-particle spectral shapes are similar and a difference in the {alpha}-particle mean energy of only 0.7 MeV is deduced. A description in terms of energy localization of entry states is given. (orig.)

1999-10-01

123

Aerosol characteristics over coastal regions of the Arabian Sea  

Energy Technology Data Exchange (ETDEWEB)

From aerosol spectral optical depths ({tau}{sub p{lambda}}) at wavelengths in the range 380 to 1025 nm estimated at different locations in the near and far coastal regions of the Arabian sea adjoining the western coast of central India, the spatial and spectral characteristics of coastal aerosols and the effect of the proximity to the (urban) continent are investigated. The Aangstroem parameters are deduced from {tau}{sub p{lambda}} values. A significant increase, both in aerosol optical depths at shorter (visible) wavelengths ({lambda} {<=} 600 nm) and the Aangstroem wavelength exponent are observed in the near coastal regions, suggesting an increase in the (relative) concentration of sub micron particles, apparently of anthropogenic origin. The Aangstroem turbidity coefficient remains nearly steady spatially, indicating a (spatially) uniform loading of large particles. 31 refs, 10 figs, 1 tab

1997-09-01

124

Acoustic band gaps in arrays of neutral inclusions  

British Library Electronic Table of Contents (United Kingdom)

We analyse numerically the acoustic stop band properties of an array of orthotropic coated cylinders whose elastic parameters are deduced from a geometric transform [H. Chen, C.T. Chan, Acoustic cloaking in three dimensions using acoustic metamaterials, Appl. Phys. Lett. 91 (2007) 183518]. We find that whereas a single coated inclusion is acoustically neutral at any frequency, an array of them might display some stop bands. More precisely, an array of freely vibrating coated voids is always neutral, whereas an array of clamped coated inclusions might display a zero frequency stop band. Interestingly, an array of radially symmetric coated inclusions behaves as local Helmholtz resonators, for which the eigenfield within each cloak is obtained in closed form, leading to a frequency estimate a...

2010-01-01

125

Absorption of carbon dioxide at high partial pressures in 1-amino-2-propanol aqueous solution. Considerations of thermal effects  

Energy Technology Data Exchange (ETDEWEB)

In the present work, the process of carbon dioxide absorption is analyzed at high partial pressures, in aqueous solutions of 1-amino-2-propanol (monoisopropanolamine (MIPA)), in relation to the thermal effects involved. All experiments were made in a stirred-tank reactor with a plane unbroken gas-liquid interface. The variables considered were the MIPA concentration within the range 0.1--2.0 M and the temperature within the interval 288--308 K. From the results, the authors deduce that the absorption process takes place in the nonisothermal instantaneous regime and propose an equation which not only relates the experimental results of flow density with the initial concentration of amine but at the same time enables the evaluation of the rise in temperature in the gas-liquid interface.

1997-10-01

126

A numerical study of ultra-short-pulse reflectometry  

Energy Technology Data Exchange (ETDEWEB)

Ultra-short-pulse reflectometry is studied by means of the numerical integration of a one-dimensional full-wave equation for ordinary modes propagating in a plasma. The numerical calculations illustrate the potential of using the reflection of ultra-short-pulse, microwaves as an effective probe of the density profile even in the presence of significant density fluctuations. The difference in time delays of differing frequency components of the microwaves can be used to deduce the density profile. The modification of the reflected pulses in the presence of density fluctuations is examined and can be understood based on considerations of Bragg resonance. A simple and effective profile-reconstruction algorithm using the zero-crossings of the reflected pulse and subsequent Abel inversion is demonstrated. The robustness of the profile reconstruction algorithm in the presence of a sufficiently small amplitude density perturbation is assessed.

1994-05-01

127

Semi-empirical calculation of air-broadened half-widths and air pressure-induced frequency shifts of water-vapor absorption lines  

International Nuclear Information System (INIS)

This paper describes a semi-empirical calculation of the air-broadened half-widths and the air pressure-induced frequency shifts for the H_2"1"6O isotopologue. This semi-empirical calculation is based on fits of several recent high-quality measurements and theoretical calculations to the first-order terms in the expansion of the complex Robert-Bonamy (CRB) equations, which yields a second- and first-order polynomial function of the differences in the upper- and lower-state vibrational quantum numbers for the half-width and line shift, respectively. The aim of this work was to obtain a complete set of air-broadened half-widths and air pressure-induced frequency shifts for transitions of H_2"1"6O present in the HITRAN database from microwave to the visible in order to supplement the observed and calculated values. For around 700 sets of rotational quantum numbers (J"'K_a"'K_c"'<-J"''K_a"''K_c"''), semi-empirical coefficients describing the vibrational dependence of the air-broadened ...

2005-12-01

128

Seismic stratigraphy in the South Cretan fault valley system: A comparison with the upper Quaternary gravitative sedimentation of the region  

Energy Technology Data Exchange (ETDEWEB)

A synthesis of the sedimentation processes as deduced from the seismic stratigraphy and the deduced facies associations suggests the following. Small fans developed along the northern major fault line of the SCFVS and contains sediment fed directly from Crete through a series of small canyons, most of which trend perpendicular to the coast. However, the main east-west-trending valley transects the mid- and lower fan sectors and contains several intravalley basinal areas, converging toward the main Messara basin. Thus much of the suprafan sediment is reworked and longitudinally transported into the deeper basins. In these deeper intrabasinal and main basinal areas the thickness of the post-Messinian sediments generally exceeds 800 m and in places exceeds 1,500 m. Toward the south the SCFVS receives additional sediment from the Ptolemy Mountains and the Gavdos rise. Cores recovered along the SCFVS contain a remarkable association of sedimentary ...

1988-08-01

129

Radon exhalation from and diffusion in concrete  

International Nuclear Information System (INIS)

Cylindrical test pieces of concrete are used for measurements of "2"2"2Rn exhalation rates. Except one flat end surface of a test piece, other parts of its exteriority are covered with sealant. Radon atoms can escape only through its end surface from the interior into the outside air. This treatment makes the radon transport in the concrete one dimensional phenomena. The piece is put in an airtight container. Time variations of radon concentrations in the air of the container are measured with a plane multiwire-electrode ionization chamber. From this result, the radon areal exhalation rate is deduced for the piece. Exhalation rates are measured for four pieces with different length. Then, the diffusion coefficient is obtained for radon in the concrete as (5.0 #+-# 1.0) x 10"-"8m"2s"-"1 (a one-block method). A two-block method has been invented to obtain simultaneously values of three parameters: diffusion coefficient, porosity of concrete, and radon production rate ...

1990-12-01

130

Molecular cloning, characterization, and expression of human ADP-ribosylation factors: Two guanine nucleotide-dependent activators of cholera toxin  

International Nuclear Information System (INIS)

ADP-ribosylation factors (ARFs) are small guanine nucleotide-binding proteins that enhance the enzymatic activities of cholera toxin. Two ARF cDNAs, ARF1 and ARF3, were cloned from a human cerebellum library. Based on deduced amino acid sequences and patterns of hybridization of cDNA and oligonucleotide probes with mammalian brain poly(A)"+ RNA, human ARF1 is the homologue of bovine ARF1. Human ARF3, which differs from bovine ARF1 and bovine ARF2, appears to represent a newly identified third type of ARF. Hybridization patterns of human ARF cDNA and clone-specific oligonucleotides with poly(A)"+ RNA are consistent with the presence of at least two, and perhaps four, separate ARF messages in human brain. In vitro translation of ARF1, ARF2, and ARF3 produced proteins that behaved, by SDS/PAGE, similar to a purified soluble brain ARF. Deduced amino acid sequences of human ARF1 and ARF3 contain regions, similar to those in other G proteins, that ...

1989-01-01

131

Molecular cloning of chicken metallothionein. Deduction of the complete amino acid sequence and analysis of expression using cloned cDNA  

Energy Technology Data Exchange (ETDEWEB)

A cDNA library was constructed using RNA isolated from the livers of chickens which had been treated with zinc. This library was screened with a RNA probe complementary to mouse metallothionein-I (MT), and eight chicken MT cDNA clones were obtained. All of the cDNA clones contained nucleotide sequences homologous to regions of the longest (375 bp) cDNA clone. The latter contained an open reading frame of 189 bp, and the deduced amino acid sequence indicates a protein of 63 amino acids of which 20 are cysteine residues. Amino acid composition and partial amino acid sequence analyses of purified chicken MT protein agreed with the amino acid composition and sequence deduced from the cloned cDNA. Amino acid sequence comparison establish that chicken MT shares extensive homology with mammalian MTs. Southern blot analysis of chicken DNA indicates that the chicken MT gene is not a part of a large family of related sequences, but rather is likely to be ...

1988-01-25

132

Modeling of turbulent bubbly flows; Modelisation des ecoulements turbulents a bulles  

Energy Technology Data Exchange (ETDEWEB)

The two-phase flows involve interfacial interactions which modify significantly the structure of the mean and fluctuating flow fields. The design of the two-fluid models adapted to industrial flows requires the taking into account of the effect of these interactions in the closure relations adopted. The work developed in this thesis concerns the development of first order two-fluid models deduced by reduction of second order closures. The adopted reasoning, based on the principle of decomposition of the Reynolds stress tensor into two statistically independent contributions turbulent and pseudo-turbulent parts, allows to preserve the physical contents of the second order relations closure. Analysis of the turbulence structure in two basic flows: homogeneous bubbly flows uniform and with a constant shear allows to deduce a formulation of the two-phase turbulent viscosity involving the characteristic scales of bubbly turbulence, as well as an ...

2005-03-15

133

Magnetic moment of the three-quasiparticle state in /sup 177/Ta  

Energy Technology Data Exchange (ETDEWEB)

An experimental investigation was made of the ..gamma..-transitions feeding or de-exciting the 1355 keV isomeric state in /sup 177/Ta. The E2/M1 mixing ratios for the 311 keV interband transition from the isomer and for the 271 keV and the 295 keV intraband transitions within the rotational band on the isomer were determined to be delta = 0.29sup(+0.11)sub(-0.06), 0.25sup(+0.05)sub(-0.03) and 0.30sup(+0.06)sub(-0.08), respectively, employing combined measurements of the linear polarization and angular distribution of the ..gamma..-ray with the aid of conversion electron measurements. Spin and parity assignments of the isomer were confirmed to be 21/2/sup -/. The half-life of the isomer was remeasured to be Tsub(1/2) = 5.0 +- 0.2 ..mu..s and the magnetic moment was found to be ..mu.. = 0.080 +- 0.014 ..mu..sub(N). The gsub(K) and gsub(R) factors for the band on the isomer were deduced separately to be gsub(K=21/2/sup -/) = 0.062sup(+0.011)sub(-0.008) and gsub(R) = ...

1982-06-07

134

Magnetic moment of the three-quasiparticle state in "1"7"7Ta  

International Nuclear Information System (INIS)

An experimental investigation was made of the #gamma#-transitions feeding or de-exciting the 1355 keV isomeric state in "1"7"7Ta. The E2/M1 mixing ratios for the 311 keV interband transition from the isomer and for the 271 keV and the 295 keV intraband transitions within the rotational band on the isomer were determined to be delta = 0.29sup(+0.11)sub(-0.06), 0.25sup(+0.05)sub(-0.03) and 0.30sup(+0.06)sub(-0.08), respectively, employing combined measurements of the linear polarization and angular distribution of the #gamma#-ray with the aid of conversion electron measurements. Spin and parity assignments of the isomer were confirmed to be 21/2"-. The half-life of the isomer was remeasured to be Tsub(1/2) = 5.0 +- 0.2 #mu#s and the magnetic moment was found to be #mu# = 0.080 +- 0.014 #mu#sub(N). The gsub(K) and gsub(R) factors for the band on the isomer were deduced separately to be gsub(K=21/2"-) = 0.062sup(+0.011)sub(-0.008) and gsub(R) = ...

135

Cloning of Drosophila transcription factor Adf-1 reveals homology to Myb oncoproteins.  

Science.gov (United States)

The Drosophila sequence-specific DNA binding protein, Adf-1, is capable of activating transcription of the alcohol dehydrogenase gene, Adh, and is implicated in the transcriptional control of other developmentally regulated genes. We have cloned the cDNA encoding Adf-1 by generating specific DNA probes deduced from partial amino acid sequence of the protein. Several cDNA clones encoding an extended open reading frame were isolated from a phage lambda library. The complete amino acid sequence of Adf-1 deduced from the longest cDNA reveals structural similarities to the putative helix-turn-helix DNA binding motif of Myb and Myb-related proteins. DNA sequence analysis of genomic clones and Northern blot analysis of mRNA suggest that Adf-1 is a single-copy gene encoding a 1.9-kb transcript. Purified recombinant Adf-1 expressed in Escherichia coli binds specifically to Adf-1 recognition sites and activates transcription of a synthetic Adh promoter ...

1992-01-15

136

\\psi(2S) Decays into $\\J$ plus Two Photons  

CERN Document Server

Using $\\gamma \\gamma J/\\psi, J/\\psi \\ra e^+ e^-$ and $\\mu^+ \\mu^-$ events from a sample of $14.0\\times 10^6$ $\\psip$ decays collected with the BESII detector, the branching fractions for $\\psip\\ra \\pi^0\\J$, $\\eta\\J$, and $\\psi(2S)\\ar\\gamma\\chi_{c1},\\gamma\\chi_{c2}\\ar\\gamma\\gamma\\jpsi$ are measured to be $B(\\psip\\ra \\pi^0\\J) = (1.43\\pm0.14\\pm0.13)\\times 10^{-3}$, $B(\\psip\\ra \\eta\\J) = (2.98\\pm0.09\\pm0.23)%$, $B(\\psi(2S)\\ar\\gamma\\chi_{c1}\\ar\\gamma\\gamma\\jpsi) = (2.81\\pm0.05\\pm 0.23)%$, and $B(\\psi(2S)\\ar\\gamma\\chi_{c2}\\ar\\gamma\\gamma\\jpsi) = (1.62\\pm0.04\\pm 0.12)%$.

2004-01-01

137

Theoretical study of asymmetric molecular-frame photoelectron angular distributions for C 1s photoejection from CO2  

Energy Technology Data Exchange (ETDEWEB)

We report the results of ab initio calculations of cross sections and molecular-frame photoelectron angular distributions for C 1s ionization of CO2, and propose a mechanism for the recently observed asymmetry of those angular distributions with respect to the CO^+and O^+ions produced by subsequent Auger decay. The fixed-nuclei, photoionization amplitudes were constructed using variationally obtained electron-molecular ion scattering wave functions. We have also carried out electronic structure calculations which identify a dissociative state of the CO2^++ dication that is likely populated following Auger decay and which leads to O^+ + CO^+ fragment ions. We show that a proper accounting of vibrational motion in the computation of the photoelectron angular distributions, along with reasonable assumptions about the nuclear dissociation dynamics, gives results in good agreement with recent experimental observations. We also demonstrate that ...

2009-02-18

138

T=(5/2) "2"7Na from "1"4C+"1"4C, and the N=16 shell gap  

International Nuclear Information System (INIS)

For the first time a comprehensive level and decay scheme has been obtained for a T=(5/2) nucleus in the s-d shell ("2"7Na) by using a radioactive beam and target. Particle-#gamma# and p-#gamma#-#gamma# coincidences were measured following the "1"4C("1"4C,p#gamma#)"2"7Na reaction at E_l_a_b=22 MeV. The results do not support an inversion of the 2s_1_/_2 and 1d_5_/_2 orbitals, as previously proposed for T_z#>=#3, but they do suggest an increased N=16 gap between the 2s_1_/_2 and 1d_3_/_2 orbitals due to the neutron excess. A consistent interpretation of the level scheme in terms of the s-d shell model using the USD Hamiltonian is possible below 4 MeV, but differences increase at higher excitation energies. Another interpretation is that the influences of both the p_1_/_2 and f_7_/_2 intruder orbitals increase simultaneously with increasing T, an effect not included in the USD Hamiltonian.

2002-05-01

139

Synthesis, characterization and antitumor activity study of some cyclometalated organoplatinum(II) complexes containing aromatic N-donor ligands  

British Library Electronic Table of Contents (United Kingdom)

A general approach has been designed to synthesize some mononuclear and binuclear cyclometalated platinum(II) complexes, containing aromatic N-donor ligands with the presence of one Cl- trans to carbon. In this way, cyclometalated platinum(II) complex [Pt(C^N)Cl(dmso)], 1, C^N = N(1),C(2prime)-chelated, deprotonated 2-phenylpyridine and dmso = dimethylsulfoxide, was used as a precursor to react with imidazole derivatives (1-methylimidazole, 2a, imidazole, 2b,), monodentate pyridine derivatives (4-methylpyridine, 2c, pyridine, 2d,) and bidentate pyridine derivative (4,4prime-bipyridine, 3 and 4,). Synthesized complexes were fully characterized by using multinuclear NMR spectroscopy (1H, 13C{1H} and 195Pt), correlation NMR spectroscopy (1H-1H COSY, 13C{1H}-1H Heteronuclear Multiple Quantum C...

2011-01-01

140

Partial Isometries of a Sub-Riemannian Manifold  

CERN Document Server

In this paper, we obtain the following generalisation of isometric $C^1$-immersion theorem of Nash and Kuiper. Let $M$ be a smooth manifold of dimension $m$ and $H$ a rank $k$ subbundle of the tangent bundle $TM$ with a Riemannian metric $g_H$. Then the pair $(H,g_H)$ defines a sub-Riemannian structure on $M$. We call a $C^1$-map $f:(M,H,g_H)\\to (N,h)$ into a Riemannian manifold $(N,h)$ a {\\em partial isometry} if the derivative map $df$ restricted to $H$ is isometric; in other words, $f^*h|_H=g_H$. The main result states that if $\\dim N>k$ then a smooth $H$-immersion $f_0:M\\to N$ satisfying $f^*h|_H

2010-01-01

141

Integral cross sections of 50.5 MeV #alpha# particle inelastic scattering on 1p and (2s-1d) shell nuclei and scattering mechanisms  

International Nuclear Information System (INIS)

Obtained experimental data on integral cross sections (ICS) of inelastic scattering of 50.5 MeV #alpha# particles with the excitation of "6","7Li, "9Be, "1"2","1"3C, "1"4C, "1"4N, "2"0Ne, "2"4Mg, "2"8Si nucleus low-lying energy levels are discussed. Regularities, detected in the behaviour of ICS forward scattering for 20-90 deg angles and backscattering for 90-160 deg angles for the target-nucleus under investigation are considered. Effect of reaction open channel number on #alpha#-particle scattering ICS where n,p,d- and #alpha#-channels were considered as the main channels for all the target-nuclei, is discussed. Dependence of #alpha#-particle scattering ICS on the target-nucleus level excitation energy and dependences of reaction open channel number on the channel spin, calculated for 50.5 MeV #alpha# particles and different target nuclei are shown in the diagrams. It is noted that the observed ...

142

Effect of heat transfer augmentation by square rod array in impinging air jet system(heat transfer characteristic of potential core region)  

Energy Technology Data Exchange (ETDEWEB)

This research has been proceeded over the potential core region (H/B=2) of two-dimensional impinging air jet system, in which square rods(width of 6 mm) has been set up in front of heating surface in order to increase heat transfer. The objective of this research was to investigate the characteristics of heat transfer and air flow, in cases of the clearance from rods to heating surface (C = 1, 2, 4, 6 mm) and the pitch between each rods(P = 30, 40, 50 mm) changed. And this research compared the above with the experimentation without rods. As result, heat transfer performance was best under the condition of C = 1 mm, in case clearance changed, and there was no serious difference in the effect of heat transfer augmentation in the case of pitch of rods changed. (author) 11 refs. 12 figs.

1995-07-01

143

Double umbrella structure in terbium iron garnet  

International Nuclear Information System (INIS)

The umbrella magnetic structure of the terbium iron garnet (TbIG) has been studied using neutron diffraction experiments peformed in the 4.2 to 650 K temperature range which covers both the Neel temperature (Tsub(N) = 550 +- 10 K) and the compensation temperature (Tsub(comp) = 244 +- 2 K). When T > Tsub(N), the observed peak intensities originate from nuclear contribution only. When Tsub(comp) < T < Tsub(N), the results have been interpreted in the Neel theory of ferrimagnetism. Below Tsub(comp), three salient features have been observed: there appears superstructure lines forbiden by the cubic space group Ia3d, whereas the other superstructure peaks are found absent contrary to other heavy rare earth garnets; the strongest reflexion (110) vanishes near Tsub(comp). The magnetic modes associated to the rhombohedral symmetry space group R(-3)c have been calculated; the two inequivalent magnetic sites C_1 and ...

1984-04-10

144

lnc0698c.091  

Science.gov (United States)

t5I gU9S y`xmRv A'b9 (RW$ F]>H ?ts6@ Snnl yHl$- #|t_C 6G8@ u,H8 3($ds #~^iy { aN2s VFR@1 zs|9n] %pyNv Z{+; !C 1cs= ||8_ 6r$0j n9X 8n`@ ,FH8S hg3` TBq*p UP09 ...

145

The effect of flow velocity on pitting corrosion and stress corrosion cracking of reactor materials  

International Nuclear Information System (INIS)

This paper describes two research programs which are currently underway in the author's laboratory to investigate the effect of fluid flow on the degradation of power plant materials in high temperature/high pressure aqueous environments. These programs include the design and operation of a controlled hydrodynamic corrosion testing apparatus that can be used to study the general and localized corrosion characteristics of alloys in simulated nuclear reactor environments, and a study of the effect of flow velocity on the stress corrosion cracking of ASTM A508 C1.2 steel and Type 304SS in simulated BWR heat transport fluids.

146

Sharp regularity for certain nilpotent group actions on the interval  

CERN Document Server

According to the classical Plante-Thurston Theorem, all nilpotent groups of $C^2$-diffeomorphisms of the closed interval are Abelian. Using techniques coming from the works of Denjoy and Pixton, Farb and Franks constructed a faithful action by $C^1$-diffeomorphisms of $[0,1]$ for every finitely-generated, torsion-free, non-Abelian nilpotent group. In this work, we give a version of this construction that is sharp in what concerns the H\\"older regularity of the derivatives. Half of the proof relies on results on random paths on Heisenberg-like groups that are interesting by themselves.

2011-01-01

147

Photoassisted hydrogen generation by integrated electroactive SPE membrane system  

Energy Technology Data Exchange (ETDEWEB)

Incorporation of TiO{sub 2}, into perfluoroionomer membrane by treatment with TiC1{sub 4}-methanol has been described. Platinum was used as an electrocatalyst. In order to make the system electronically as well as ionically conducting, the electrode was modified with polypyrrole (PPy). Photopolymerisation of pyrrole was accomplished by immersing TiO{sub 2}-Pt-NaF in pyrrole solution. UV-visible and FT-IR Spectroscopic studies were preformed with regards to the formation of the TiO{sub 2}, Pt and PPy within Nafion matrix. We report the construction and evaluation of this integrated system and establish the feasibility of hydrogen generation thereof. (Author)

2000-04-01

148

Intermediate scale borehole (Room C): In situ data report (January 1989--June 1993)  

Energy Technology Data Exchange (ETDEWEB)

Data are presented from the intermediate scale borehole test, an in situ test fielded in the pillar separating Rooms C1 and C2 at the Waste Isolation Pilot Plant (WIPP). The test was to provide data on the influence of scale, if any, on the structural behavior of underground openings in salt. These data include selected fielding information, test configuration, instrumentation activities, and comprehensive results from a large number of gages. Construction of the test began in December 1989, with the drilling of the intermediate scale borehole in December 1990. Gage data in this report cover the period from January 1989 through June 1993.

1994-11-01

149

&C:sIC> uC%m$C C(k6C* 1CFM 2dC% !C3U J*C0! CV$,Co\\ lC$\\JC ...  

Science.gov (United States)

C C*R C" dC*9 4hC2 CX2VCTF CK/XCL` CCNA C?Q C.:FC C?v As1)Ax^IA} AyU$ =FA%WNA AfgJA Aw;ZAzg AyA!A A=!nA> CA!n/A* ? ...

150

Molecular orbitals of nucleons in nucleus-nucleus collisions  

International Nuclear Information System (INIS)

A formalism for the dynamical treatment of the molecular orbitals of valence nucleons in nucleus-nucleus collisions is developed with the use of the coupled-reaction-channel (CRC) method. The Coriolis coupling effects as well as the finite mass effects of the nucleon are taken into account in this model, of rotating molecular orbitals, RMO. First, the validity of the concept is examined from the viewpoint of the multi-step processes in a standard CRC calculation for systems containing two identical [core] nuclei. The calculations show strong CRC effects particularly in the case where the mixing of different l-parity orbitals - called hybridization in atomic physics - occurs. Then, the RMO representation for active nucleons is applied to the same systems and compared to the CRC results. Its validity is investigated with respect to the radial motion (adiabaticity) and the rotation of the molecular axis (radial and rotational coupling). Characteristic molecular orbitals of covalent ...

151

Changes in soil N fractions and utilization of recently immobilized fertilizer N by wheat as influenced by application of some organic chemicals in rice-wheat sequence  

International Nuclear Information System (INIS)

Effect of two organic chemicals viz., 2,4-dinitrophenyl hydrazone (C_1) and naphthyl ethylene diamine (C_2) was studied by their application alone and together (Csub(1+2) at the rate of 10 ppm by growing wheat on a loamy soil (Typic ustochrept) containing recently immobilized fertilizes N of "1"5N - urea applied at 60, 120 and 180 ppm N to preceding rice under greenhouse conditions of a rice-wheat sequence. The application of C_1 and C_2 alone; and their combined application (Csub(1+2) produced 12, 15 and 18 per cent higher wheat grain yield over no-chemical application i.e. Co (3.50 g/pot). The chemicals also showed their beneficial effect on utilization of recently immobilized fertilizer N, as was evidenced by significantly higher "1"5N recovery values in wheat with C_1, C_2 and Csub(1+2)(2.84, 3.63 and 3.54 per cent, respectively) than that of Co (2.29 per ...

152

h-cobordism and s-cobordism Theorems: Transfer over Semialgebraic and Nash categories, Uniform bound and Effectiveeness  

CERN Document Server

The h-cobordism theorem is a noted theorem in differential and PL topology. A generalization of the h-cobordism theorem for possibly non simply connected manifolds is the so called s-cobordism theorem. In this paper, we prove semialgebraic and Nash versions of these theorems. That is, starting with semialgebraic or Nash cobordism data, we get a semialgebraic homeomorphism (respectively a Nash diffeomorphism). The main tools used are semialgebraic triangulation and Nash approximation. One aspect of the algebraic nature of semialgebraic or Nash objects is that one can measure their complexities. We show h and s-cobordism theorems with a uniform bound on the complexity of the semialgebraic homeomorphism (or Nash diffeomorphism) obtained in terms of the complexity of the cobordism data. The uniform bound of semialgebraic h-cobordism cannot be recursive, which gives another example of non effectiveness in real algebraic geometry see [ABB]. Finally we deduce the validity ...

2009-01-01

153

cDNA cloning and sequence analysis of preproendothelin-1 (PPET-1) from salmon, Oncorhynchus keta.  

Science.gov (United States)

The presence of endothelin (ET)-like immunoreactivity and the cardiovascular effects of mammalian ET-1 in fish have been reported. To identify ET-related peptides in fish, we screened the cDNA library of the salmon (Oncorhynchus keta) stomach by means of rapid amplification of cDNA ends, and we cloned cDNAs encoding an ET-related peptide. The salmon ET-related sequence of 21 amino acids is identical to the trout ET-1 peptide recently purified from kidney specimens of Oncorhynchus mykiss. The deduced amino acid sequence of salmon pre-proET-1 (PPET-1) comprises 244 amino acids, including a putative signal sequence and mature ET-1, as well as big ET-1 and ET-1-like sequences. This precursor, the first reported PPET-1 sequence for Salmoniformes, Teleostei, has low homology with the sequences of human, mouse, frog (Xenopus laevis), and zebrafish (Danio rerio) PPET-1 (26%, 29%, 24%, and 39%, respectively). PMID:16740985

2006-06-01

154

X-ray absorption spectroscopy, EELS, and full-potential augmented plane wave study of the electronic structure of Ti_2AlC, Ti_2AlN, Nb_2AlC, and (Ti_0_._5Nb_0_._5)_2AlC  

International Nuclear Information System (INIS)

The structural parameters of various Haegg phases (H or M_n_+_1AX_n phases) are studied experimentally by x-ray and electron spectroscopies, x-ray diffraction, and ab initio full potential as well as full mutiple scattering theoretical calculations. Experimentally it was found that the structure of all ternary compounds analyzed herein are relaxed. The values of the lattice parameters and relaxations obtained from ab initio calculations are in excellent agreement with those deduced from the analysis of the experimental data. The bonding scheme has been analyzed and the charge transfer between constituting atoms determined. It is demonstrated that the strength and electrical transport properties in these materials are principally governed by the metallic planes. For the solid solution (Ti_0_._5Nb_0_._5)_2AlC, the most salient result is that the basal planes are corrugated, which could explain the solid solution scattering observed in this H phase.

2005-01-01

155

Two-nucleon multiplets near mass A = 88 and the implication for the residual nucleon-nucleon interaction  

Energy Technology Data Exchange (ETDEWEB)

The low excitation energy spectroscopy of /sup 86/Sr, /sup 88/Sr, /sup 89/Sr, /sup 86/Rb, and /sup 87/Rb nuclear systems was studied via one-nucleon transfer reactions. The strontium isotopes, /sup 87/Sr and /sup 88/Sr, were used as targets in this study. Spectroscopic strengths were extracted from the measured transfer reaction cross sections and the distorted wave Born approximation (DWBA) analysis. Efforts have been made to accomplish a complete detection of spectroscopic strengths through the excitation energy region where levels can be resolved and identified. A shell model sum rule analysis is then made. Diagonal matrix elements for the effective two-nucleon interaction were deduced from empirical energy centroid. Matrix elements normalized by their empirical monopole energy was plotted against the semiclassical angle between two spins. They were compared with various analytical function forms of the effective two-nucleon interaction depending on their spins, ...

1987-01-01

156

Two-nucleon multiplets near mass A = 88 and the implication for the residual nucleon-nucleon interaction  

International Nuclear Information System (INIS)

The low excitation energy spectroscopy of "8"6Sr, "8"8Sr, "8"9Sr, "8"6Rb, and "8"7Rb nuclear systems was studied via one-nucleon transfer reactions. The strontium isotopes, "8"7Sr and "8"8Sr, were used as targets in this study. Spectroscopic strengths were extracted from the measured transfer reaction cross sections and the distorted wave Born approximation (DWBA) analysis. Efforts have been made to accomplish a complete detection of spectroscopic strengths through the excitation energy region where levels can be resolved and identified. A shell model sum rule analysis is then made. Diagonal matrix elements for the effective two-nucleon interaction were deduced from empirical energy centroid. Matrix elements normalized by their empirical monopole energy was plotted against the semiclassical angle between two spins. They were compared with various analytical function forms of the effective two-nucleon interaction depending on their spins, isospins, and parities.

157

The response of some TL albedo neutron dosimeters  

International Nuclear Information System (INIS)

As part of a general study of personnel neutron dosimetry systems, three British and two German TL albedo dosimeters were compared. They range from simple albedo devices to multi-element devices which detect combinations of incident and albedo neutrons. They were exposed to beams of mono-energetic neutrons, a thermal neutron column and a "2"5"2Cf source. The variation in response with neutron energy above 0.1 MeV was similar for all dosimeters. The resuls show that in general multi-component dosimeters fo not provide enough information to deduce the effective energy of incident neutrons. The choice of single or multi-element dosimeters for particular types of environment is discussed. The Harvey dosimeter has the most acceptable thermal neutron response of the simpler devices. For neutron energies below 0.5 MeV its response varies roughly as the cosine of the angle of incidence but is more complex at higher energies. (author).

158

The pp{yields}K{sup +}{sigma}{sup +}n cross-section from missing-mass spectra  

Energy Technology Data Exchange (ETDEWEB)

We utilize existing inclusive data on K{sup +}-meson momentum spectra of the reaction pp{yields}K{sup +}X at T{sub p}=2.3-2.85 GeV to deduce total cross-sections for pp{yields}K{sup +}{sigma}{sup +}n. The method used to extract those cross-sections is explained and discussed in detail. Our result for T{sub p}=2.85 GeV is consistent with the data point from a direct measurement at the same beam energy. The cross-section obtained for T{sub p}=2.3 GeV is with 13.7{+-}2.3 {mu}b considerably smaller than the value found in a recent experiment by the COSY-11 Collaboration at a somewhat lower beam energy, indicating that the pp{yields}K{sup +}{sigma}{sup +}n reaction cross-section could exhibit a rather unusual energy dependence. (orig.)

2007-05-15

159

The non-linear fitting method to analyze the measured M-S plots of bipolar passive films  

Energy Technology Data Exchange (ETDEWEB)

Mott-Schottky (M-S) analysis is an effective approach to investigate the electronic property of passive films of metals, and it is well suitable for the passive film with single space charge capacitance. But there is no proper method to analyze the C{sub sc}{sup -2} vs. V{sub m} plots of passive films with several space charge capacitances in series connection, such as bipolar passive films. In this paper, the relationship between the space charge capacitance of the bipolar passive film and the applied potential was deduced and the features of corresponding plots were given out simultaneously. Accordingly, a non-linear fitting method was presented to analyze the C{sub sc}{sup -2} vs. V{sub m} plots of bipolar passive films. Then the method was used to study the semiconductor characteristics of bipolar passive films formed on the surface of Nickel base alloy after being corroded in the environments with high temperatures and high partial pressures of H{sub ...

2010-02-28

160

The non-linear fitting method to analyze the measured M-S plots of bipolar passive films  

International Nuclear Information System (INIS)

Mott-Schottky (M-S) analysis is an effective approach to investigate the electronic property of passive films of metals, and it is well suitable for the passive film with single space charge capacitance. But there is no proper method to analyze the Csc-2 vs. Vm plots of passive films with several space charge capacitances in series connection, such as bipolar passive films. In this paper, the relationship between the space charge capacitance of the bipolar passive film and the applied potential was deduced and the features of corresponding plots were given out simultaneously. Accordingly, a non-linear fitting method was presented to analyze the Csc-2 vs. Vm plots of bipolar passive films. Then the method was used to study the semiconductor characteristics of bipolar passive films formed on the surface of Nickel base alloy after being corroded in the environments with high temperatures and high partial pressures of H2S/CO2. The fitting results indicate that the ...

2010-02-28

161

The nanostructure and microstructure of steels: Electrochemical Tafel behaviour and atomic force microscopy  

International Nuclear Information System (INIS)

The influence of chemical composition and heat treatment on a low-carbon steel, chromium steel and high speed steel has been examined by polarisation curves and electrochemical parameters deduced from the Tafel plots. The electrochemical corrosion resistance, which is small between the as-received steels become greater after heat treatment, following the order: carbon steel < chromium steel #approx# high speed steel. To explain these differences, the nano- and microstructure of the steels has been characterized by the ex situ techniques of atomic force microscopy and optical microscopy, before and after surface etching with Nital (a solution of 5% HNO_3 in ethanol). This causes preferential attack of the ferrite phases showing the carbide phases more clearly. From these nanostructural studies it was possible to better understand why the passive films formed on chromium steel and high speed steel have superior protective properties to those formed on carbon ...

2005-12-01

162

Synchrotron Self-Compton Analysis of TeV X-ray Selected BL Lacertae Objects  

CERN Document Server

We introduce a methodology for analysis of multiwavelength data from X-ray selected BL Lac (XBL) objects detected in the TeV regime. By assuming that the radio--through--X-ray flux from XBLs is nonthermal synchrotron radiation emitted by isotropically-distributed electrons in the randomly oriented magnetic field of a relativistic blazar jet, we obtain the electron spectrum. This spectrum is then used to deduce the synchrotron self-Compton (SSC) spectrum as a function of the Doppler factor, magnetic field, and variability timescale. The variability timescale is used to infer the comoving blob radius from light travel-time arguments, leaving only two parameters. With this approach, we accurately simulate the synchrotron and SSC spectrum of flaring XBLs in the Thomson through Klein-Nishina regimes. Photoabsorption by interactions with internal jet radiation and the intergalactic background light (IBL) is included. Doppler factors, magnetic fields, and absolute jet ...

2008-01-01

163

Study of iodine migration in zirconia using stable and radioactive ion implantation  

Energy Technology Data Exchange (ETDEWEB)

The large uranium fission cross section leading to iodine and the behaviour of this element in the cladding tube during energy production and afterwards during waste storage is a crucial problem, especially for {sup 129}I which is a very long half-life isotope (T=1.59 x 10{sup 7} yr). Since a combined external and internal oxidation of the zircaloy cladding tube occurs during the reactor processing, iodine diffusion parameters in zirconia are needed. In order to obtain these data, stable iodine atoms were first introduced by ion implantation into zirconia with an energy of 200 keV and a dose equal to 8 x 10{sup 15} at cm{sup -2}. Diffusion profiles were measured using 3 MeV alpha-particle Rutherford backscattering spectrometry at each step of the annealing procedure between 700 C and 900 C. In such experiments a reduced iodine concentration was observed, which correlated to a diffusion-like process. Similar analysis has been performed using radioactive {sup 131}I implanted at a very ...

1998-03-01

164

Spectroscopic properties of Eu sup 3+ in lanthanum chlorotungstates  

Energy Technology Data Exchange (ETDEWEB)

The spectroscopic properties of Eu{sup 3+} doped into two lanthanum chlorotungstates matrices, namely LaWO{sub 4}Cl (1-1) and La{sub 3}WO{sub 6}Cl{sub 3}(3-1), are investigated. The fluorescence spectra of these compounds, recorded at room and liquid nitrogen temperatures, show that the lanthanide ion occupies only one site with the low symmetry, C{sub s}, in both cases. From the energy level schemes of the {sup 7}F{sub J} levels (J = 0, 1, 2, 3, 4, 5), two sets of crystal field parameters (cfp) are deduced, in a C{sub 2v} approximated point symmetry (i.e., 9 cfp), simulating the experimental data, correctly. Furthermore, for the 3-1 compound, the data is complete enough to extend the calculations to the real point group, C{sub s} (14 cfp).

1990-11-01

165

SnO{sub 2} thin films morphological and optical properties in terms of the Boubaker Polynomials Expansion Scheme BPES-related Opto-Thermal Expansivity {psi}{sub AB}  

Energy Technology Data Exchange (ETDEWEB)

In this study, SnO{sub 2} thin films have been grown using spray pyrolysis technique on glass substrates under a substrate temperature (T{sub s} = 440 {sup o}C). The precursors were methanol CH{sub 4}O and anhydrous tin tetrachloride. XRD analyses yielded strong (1 1 0)-(1 0 1)-(2 0 0) X-ray diffraction peaks which are characteristics to tetragonal crystals. Atomic Force Microscopy (AFM) analyses showed the existence of clusters with particular pyramidal shapes. The main part of this study concerns the optical measurements of transmittance T({lambda}) and reflectance R({lambda}) spectra inside 250-1800 nm domain. Conjoint optical and thermal properties were deduced using the Amlouk-Boubaker Opto-Thermal Expansivity {psi}{sub AB}. The obtained value: {psi}{sub AB} {approx} 23.4 m{sup 3} s{sup -1} helped situating the performance of the as-grown SnO{sub 2} compound among most known PV-T oxides like ZnO and TiO{sub 2}.

2010-02-04

166

SnO2 thin films morphological and optical properties in terms of the Boubaker Polynomials Expansion Scheme BPES-related Opto-Thermal Expansivity ?AB  

International Nuclear Information System (INIS)

In this study, SnO2 thin films have been grown using spray pyrolysis technique on glass substrates under a substrate temperature (Ts = 440 oC). The precursors were methanol CH4O and anhydrous tin tetrachloride. XRD analyses yielded strong (1 1 0)-(1 0 1)-(2 0 0) X-ray diffraction peaks which are characteristics to tetragonal crystals. Atomic Force Microscopy (AFM) analyses showed the existence of clusters with particular pyramidal shapes. The main part of this study concerns the optical measurements of transmittance T(?) and reflectance R(?) spectra inside 250-1800 nm domain. Conjoint optical and thermal properties were deduced using the Amlouk-Boubaker Opto-Thermal Expansivity ?AB. The obtained value: ?AB ? 23.4 m3 s-1 helped situating the performance of the as-grown SnO2 compound among most known PV-T oxides like ZnO and TiO2.

2010-02-04

167

Resonance ionization spectroscopy at {sup 240f,242f}Am fission isomers  

Energy Technology Data Exchange (ETDEWEB)

Optical Isotope shift measurements have been performed for the {sup 240f,242f}Am fission isomers to test the stability of nuclear deformation as function of the neutron number. The method is based on resonance ionization spectroscopy (RIS) in a buffer gas cell with fission detection of the ionization process. The {sup 240f,242f}Am fission isomers have been produced by {sup 242}Pu(p, 3n), {sup 242}Pu(d, 2n) reactions, respectively. Relative isotope shift ratios X{sub exp}{sup 242f}(500 nm)=IS{sup 242f,241}/IS{sup 243,241}=41.4(8) and X{sub exp}{sup 240f}(500 nm)=IS{sup 240f,241}/IS{sup 243,241}=39.2(8) were measured. From these ratios a small difference {delta}{beta}{sub 2}{sup 242f,240f}=0.0076(14) of the deformation parameter {beta}{sub 2} can be deduced assuming that the isotope shift between the reference isotopes {sup 241,243}Am is caused by a pure volume change. (orig.)

1997-10-01

168

Recovery of Tsub(c) by annealing of irradiated A-15 compounds  

International Nuclear Information System (INIS)

Data on the recovery of Tsub(c) for several neutron irradiated A-15 compounds are presented. A model for the mechanism of recovery is suggested and has been applied to isothermal annealing data at 550"0C on a sample of Nb_3Ge and to isochronal annealing (200"0C-900"0C) data on V_3Si, Nb_3Ge and Nb_3Sn subjected to varying doses of fast neutrons and on Nb_3Al of various compositions subjected to the same dose. The recovery is assumed to take place by vacancy assisted reordering and occurs in several stages. The major low temperature stage is attributed to irradiation induced vacancies, while at high temperatures there are depleted and recovery is ascribed to the motion of thermal equilibrium vacancies. Activation energies deduced for these processes, approximately 1 eV for vacancy motion and approximately 1-2 eV for vacancy formation, are consistent with what is known about diffusion in the A-15 structure. (Auth.).

169

Radon exhalation from uranium mill tailings: Modelisation and in situ validation  

International Nuclear Information System (INIS)

TRACI, a model based on the physical mechanisms governing the radon transport in unsaturated soils, has been developed to evaluate the radon flux density at Uranium Mill Tailings (UMT) covers surface. First, moisture contents in the soil, induced by weather conditions, are calculated. Then, radon concentrations in the air-filled pore space, and radon flux density at the soil surface, are deduced from a transport model which takes account for diffusion and convection in the pore space. To check the hypothesis used in TRACI and the efficiency of cover layers, an in situ study was launched in 1997 with the French uranium mining company, COGEMA. It consists of continuous measurements of moisture contents, suctions, radon concentrations at various depths inside an UMT cover, and flux density at its surface. The first analysis made on in situ observations shows that radon concentrations and flux density, calculated with a steady-state diffusion model using monthly ...

2002-02-01

170

Probabilistic power generation planning with environmental consideration for Lebanon  

International Nuclear Information System (INIS)

Full text.This paper describes a software tool for generation expansion planning based on dynamic programming, probabilistic production simulation, and environmental assessment. The aim is to determine the units needed to expand a given system in order to minimize either the cost or the environmental impact or some weighed function of the two. The problem of generation expansion planning is solved in stages using Tunnel Dynamic Programming (TDP) with Heuristic rules to limit the number of options analyzed. The production costing methodology is based on combining a probabilistic generation model known as the capacity outage table (COT) with the load duration curve (LDC) of the system to deduce a risk model from which the expected energy not supplied (EENS) is estimated. The generation model is built recursively using an efficient numerical convolution procedure and is combined at each step with the LDC to calculate the expected energy produced by each unit, its ...

2000-11-23

171

Preparation and photocatalytic property of pyrochlore Bi{sub 2}Ti{sub 2}O{sub 7} and (Bi, La) {sub 2}Ti{sub 2}O{sub 7} films  

Energy Technology Data Exchange (ETDEWEB)

Dopant-free Bi{sub 2}Ti{sub 2}O{sub 7} thin films with pyrochlore structure and La-doped bismuth titanate thin films have been fabricated by means of chemical solution decomposition, and characterized by X-ray diffraction, atomic force microscopy, scanning electron microscopy and UV-Vis spectrophotometry in this study. Their photocatalytic activities have been evaluated by photodegrading methyl orange solution, and the optimum processing parameters for the highest photocatalytic activity have been found. Moreover, the effects of La-doping on the phase transformation and the photocalalytic activity have been studied. It has been deduced from the experiment result that substituted La{sup 3+} ions can act as a stabilizer of Aurivillus phase BLT and a grain-growth inhibitor in BLT thin films.

2008-11-28

172

Piperidine adsorption on two different silver electrodes: A combined surface enhanced Raman spectroscopy and density functional theory study  

Energy Technology Data Exchange (ETDEWEB)

The surface enhanced Raman scattering (SERS) spectra of piperidine in silver colloid solution, on roughened silver electrode and on roughened silver electrode modified with silver nanoparticles were studied, and the high-quality SERS spectra of piperidine on roughened silver electrode modified with silver nanoparticles were obtained for the first time. Surface selection rules derived from the EM enhancement model were employed to deduce piperidine orientations on the different surfaces. On the basis of this, two models of piperidine adsorbed on the surface of the silver nanoparticles were built, and DFT-B3PW91/LanL2dz was applied to calculate the Raman frequencies. It proves that, at higher potential values, the piperidine is perpendicularly standing on the roughened silver electrode surface though its lone-electron pair, but in silver colloid solution and on the silver nanoparticles modified silver electrode the piperidine molecular lies flat on the silver ...

2007-10-15

173

Ozone transport from stratosphere to troposphere  

International Nuclear Information System (INIS)

"7Be produced by the interaction of cosmic rays with oxygen and nitrogen, predominantly in the stratosphere, has been used to identify and measure stratospheric ozone at the ground level. Simultaneous measurements at Whiteface Mountain, New York, in July 1975 show that the maximum "7Be concentrations are accompanied by increased ozone concentrations. Peaks in "7Be concentrations occurred on July 5-6, 11-12, 16-17, 23, and 27. Ozone peaks were observed on July 7-9, 11, 18, 24, and 27. Isentropic trajectory calculations also showed that the trajectories reaching Whiteface Mountain on July 11-12, 15-16, 23, and 27 had stratospheric origin. One-day delay in ozone peaks on July 7-9, 18, and 24 is attributed to increased tropospheric ozone production. The observed relationship between "7Be and ozone is used to deduce an upper limit of 37 ppb stratospheric ozone at Whiteface Mountain during July 1975. Thus, even during midsummer months, when stratospheric-tropospheric ...

174

Oxygen-concentration dependent enhancement of positive secondary ion emission from silicon  

Energy Technology Data Exchange (ETDEWEB)

The enhancement of positive secondary ion yields of silicon due to the presence of oxygen has been investigated quantitatively by low-energy (5 keV) oxygen implantation. Implantation and sputter profiling with 9 keV In/sup +/ were performed in the same ion microprobe instrument. Depth profiles of substrate and implanted oxygen atoms were measured for fluences ranging from 5x10/sup 15/ to 4x10/sup 16/ O-atoms/cm/sup 2/. The oxygen concentration, c(O), in the sample was deduced from the implanted fluence and the range distribution in the Gaussian approximation. It was found that the oxygen-enhanced Si/sup +/ intensity is proportional to c(O)sup(x) (with x=1.4) in the concentration regime, 1.5<=c(O)<=30 at%. The O/sup +/ intensity shows a similar dependence for c(O)> or approx.20 at.%.

1983-12-15

175

On the space-time scales of the surface solar radiation field  

Energy Technology Data Exchange (ETDEWEB)

The characteristic space-time scales of surface solar radiation fields measured by the 111-instrument ME-SONET in Oklahoma are estimated after removal of the diurnal cycle. These estimates of {open_quotes}within-day{close_quotes} are used to deduce the representativeness of surface solar radiation measurements measurement site as a function of time-averaging interval. Nomograms of the relation between point measurements and area averages are given for different space-time-averaging intervals. Examples from the nomograms show, for instance, that under conditions of low mean radiation (cloudy days), the central site point measurements are representative of a spatial area the size of a T42 GCM grid box (280 km X 280 km) if one uses hourly averages and is willing to accept a correlation of 0.45 between area average and point measurement. The point data represent a 60 km X 60 km region at a 0.90 correlation level if a 5-min time average is used. The characteristic ...

1998-01-01

176

On the orbital evolution and growth of protoplanets embedded in a gaseous disc  

CERN Document Server

We present a new computation of the linear tidal interaction of a protoplanetary core with a thin gaseous disc in which it is fully embedded. For the first time a discussion of the orbital evolution of cores with eccentricity (e) significantly larger than the gas-disc scale height to radius ratio (H/r) is given. We find that the direction of orbital migration reverses for e>1.1H/r. This occurs as a result of the orbital crossing of resonances in the disc that do not overlap the orbit when the eccentricity is very small. Simple expressions giving approximate fits to the eccentricity damping rate and the orbital migration rate are presented. We go on to calculate the rate of increase of the mean eccentricity for a system of protoplanetary cores due to dynamical relaxation. By equating the eccentricity damping time-scale with the dynamical relaxation time-scale we deduce that an equilibrium between eccentricity damping and excitation through scattering is attained ...

1999-01-01

177

Numerical solutions of high-frequency perturbations in Bianchi type IX models  

Energy Technology Data Exchange (ETDEWEB)

The problem in perturbation theory in general relativity is finding a natural gauge which simplifies the equations considerably. We solved the first and second order perturbation equations in the ''Lorentz gauge'' using the two-timing method. The equations were deduced from the equations of Einstein in the presence of a matter energy-momentum tensor of a perfect fluid with equation of state p = (..gamma..-1) rho. It is found that the 0--0 component of the first order equations together with the gauge conditions are consistent with the Bianchi type V model, without axial symmetry. It represents a ''ground state'' situation of the Bianchi type IX model (Mixmaster model.) The second order equations, describing the reaction back of the gravitational waves on the slowly varying background, give rise to rotation and will disturb the isotropization mechanism. The numerical solutions show all the ...

1983-05-15

178

Multidimensional two-phase flow regime distribution in a PWR downcomer during an LBLOCA refill phase  

Energy Technology Data Exchange (ETDEWEB)

The multidimensional countercurrent two-phase flow regimes that occur in a pressurized-water reactor (PWR) vessel downcomer during the refill phase of a large-break loss-of-coolant accident are studied using a transparent 1/10 scale model of a PWR vessel. The various flow regimes and their distribution in the downcomer have been identified and mapped for a range of air-water flooding experiments. The two-phase flow patterns that are identified in the downcomer included various types of film flows, droplet flows, countercurrent churn flows and cocurrent flows depending on the flooding condition. Through observation of the two-phase flow dynamics it was deduced that the physical mechanisms associated with the flooding processes could be separated into a liquid entrainment process and a film flow reversal process. In addition to the above exercise, the effect of non-uniform injection of water into the downcomer via different combinations of cold leg was studied ...

1994-09-01

179

Multidimensional two-phase flow regime distribution in a PWR downcomer during an LBLOCA refill phase  

International Nuclear Information System (INIS)

The multidimensional countercurrent two-phase flow regimes that occur in a pressurized-water reactor (PWR) vessel downcomer during the refill phase of a large-break loss-of-coolant accident are studied using a transparent 1/10 scale model of a PWR vessel. The various flow regimes and their distribution in the downcomer have been identified and mapped for a range of air-water flooding experiments. The two-phase flow patterns that are identified in the downcomer included various types of film flows, droplet flows, countercurrent churn flows and cocurrent flows depending on the flooding condition. Through observation of the two-phase flow dynamics it was deduced that the physical mechanisms associated with the flooding processes could be separated into a liquid entrainment process and a film flow reversal process. In addition to the above exercise, the effect of non-uniform injection of water into the downcomer via different combinations of cold leg was studied ...

1993-10-01

180

Mechanism for transient-enhanced diffusion in ion-implanted silicon  

International Nuclear Information System (INIS)

High-dose ion implantation followed by solid-phase-epitaxial (SPE) growth is now a well-established technique for the production of supersaturated silicon alloys. However, these alloys also contain a high supersaturation of silicon interstitials, which give rise to transient, greatly enhanced dopant diffusion with subsequent heating. In this contribution, the authors present a study of a series of Si-Sb alloys of various concentrations which were made by Sb implantation under various conditions to deduce the origin of the observed transient diffusion. A multiple implant scheme was employed to produce samples with an approximately uniform dopant concentration from 40 to 150 nm in depth, but with the amorphous layer extending to a depth of 380 nm. By scaling the implant doses, alloys with different concentrations in the uniform region were produced, allowing an accurate measure of diffusion coefficients as a function of concentration. Diffusion coefficients during ...

1985-03-01

181

Measurements of radio propagation in rock salt for the detection of high-energy neutrinos  

CERN Document Server

We present measurements of the transmission of radio/microwave pulses through salt in the Cote Blanche salt mine operated by the North American Salt Company in St. Mary Parish, Louisiana. These results are from data taken in the southwestern region of the 1500 ft. (457 m) deep level of the mine on our third and most recent visit to the mine. We transmitted and received a fast, high-power, broadband pulse from within three vertical boreholes that were drilled to depths of 100 ft. (30 m) and 200 ft. below the 1500 ft. level using three different pairs of dipole antennas whose bandwidths span 125 to 900 MHz. By measuring the relative strength of the received pulses between boreholes with separations of 50 m and 169 m, we deduce the attenuation of the signal attributed to the salt medium. We fit the frequency dependence of the attenuation to a power law and find the best fit field attenuation lengths to be 93 \\pm 7 m at 150 MHz, 63 \\pm 3 m at 300 MHz, and 36 \\pm 2 m ...

2008-01-01

182

Measurement of level lifetimes in the ps range and model interpretations for neutron-rich A #approx =# 100 nuclei  

International Nuclear Information System (INIS)

The nuclear structure of A #propor to# 100 nuclei has been studied in the frame of this thesis with a recently developed #beta# - #gamma# - #gamma# triple coincidence fast timing technique and different models such as shell model, hydrodynamic model, Nilsson and particle-rotor models. This technique which allows the measurement of the level lifetimes in the ps range has been applied at JOSEF at the research reactor DIDO of KFA Juelich in studes of the short-lived neutron-rich nuclei in the A #approx =# 100 region. Lifetimes of level in "9"6,"9"8,"1"0"0 ZR, "9"9,"1"0"1-"1"0"4 Nb, "1"0"0-"1"0"5 Mo have been measured, which are in many cases completely new, and otherwise more precise than previously published data. From the lifetimes of the members of rotational bands, the size of the nuclear deformations has been deduced. (orig./HSI).

183

Interaction of 8 MeV /sup 12/C with /sup 88/Sr; neutron transfer, inelastic scattering and spin alignment of the 2/sup +/ state of /sup 12/C  

Energy Technology Data Exchange (ETDEWEB)

Using a Q3D magnetic spectrometer the elastic and inelastic scattering of /sup 12/C on /sup 88/Sr and the neutron pick-up (/sup 12/C, /sup 13/C) has been studied. The spin alignment of the inelastically excited 2/sup +/ state of /sup 12/C (4.43 MeV) has been deduced from the line shapes broadened by the ..gamma..-decay in flight. Thus for each m-substate a full angular distribution was obtained. The m = 1 substate shows a shifted interference minimum, which is explained by the different strength of the Coulomb and nuclear amplitudes in the m-substates. The analysis of the data on elastic scattering, inelastic scattering, alignment and the neutron transfer can be described consistently with one choice of the optical model parameters.

1982-04-01

184

Input of cogeneration units in the future Dutch electric power supply. Inzet van warmte/krachteenheden in de toekomstige Nederlandse elektriciteitsvoorziening  

Energy Technology Data Exchange (ETDEWEB)

An investigation was carried out to determine the significance of a large input of cogeneration units for the electric power generation, next to the input of coal and uranium. Thereto a production plant has been set up to generate heat and electric power. The plant serves as a basis for a number of comparative calculations: basic calculations to investigate the influence of some strategies on the cogeneration input, and sensitivity calculations to determine the influence of a few changes in the starting points. Some variants have been deduced from this plant, which is based on prognosis for the year 2000. By means of the computer calculation program OPINIE (Optimale Inzet en Instelling van Eenheden: Optimal Input and Installation of Units) the minimal variable costs were calculated for different situations. Finally for each considered situation the total annual costs have been calculated. 53 figs., 13 refs., 30 tabs., 3 apps.

1987-02-01

185

Inclusive K{sup +}-meson production in proton-nucleus interactions  

Energy Technology Data Exchange (ETDEWEB)

The production of K{sup +}-mesons in pA(A=D,C,Cu,Ag,Au) collisions has been investigated at the COoler SYnchrotron COSY-Juelich for beam energies T{sub p}=1.0-2.3 GeV. Double differential inclusive pC cross-sections at forward angles {theta}{sub K+}<12 as well as the target mass dependence of the K{sup +} momentum spectra have been measured with the ANKE spectrometer. Far below the free NNthreshold at T{sub NN}=1.58 GeV the spectra reveal a high degree of collectivity in the target nucleus. From the target mass dependence of the cross-sections at higher energies, the repulsive in-medium potential of the K{sup +}-mesons can be deduced. Using pNcross-section parameterisations from the literature and our measured pD data we derive a cross-section ratio {sigma}(pn{yields}K{sup +}X)/{sigma}(pp{yields}K{sup +}X) {proportional_to}(3-4). (orig.)

2004-11-01

186

In vitro corrosion, cytotoxicity and hemocompatibility of bulk nanocrystalline pure iron  

International Nuclear Information System (INIS)

Bulk nanocrystalline pure iron rods were fabricated by the equal channel angular pressure (ECAP) technique up to eight passes. The microstructure and grain size distribution, natural immersion and electrochemical corrosion in simulated body fluid, cellular responses and hemocompatibility were investigated in this study. The results indicate that nanocrystalline pure iron after severe plastic deformation (SPD) would sustain durable span duration and exhibit much stronger corrosion resistance than that of the microcrystalline pure iron. The interaction of different cell lines reveals that the nanocrystalline pure iron stimulates better proliferation of fibroblast cells and preferable promotion of endothelialization, while inhibits effectively the viability of vascular smooth muscle cells (VSMCs). The burst of red cells and adhesion of the platelets were also substantially suppressed on contact with the nanocrystalline pure iron in blood circulation. A clear size-dependent behavior from ...

2010-12-01

187

Identification of three related human GRO genes encoding cytokine functions  

International Nuclear Information System (INIS)

The product of the human GRO gene is a cytokine with inflammatory and growth-regulatory properties; GRO is also called MGSA for melanoma growth-stimulatory activity. The authors have identified two additional genes, GRO#beta# and GRO#gamma#, that share 90% and 86% identity at the deduced amino acid level with the original GRO#alpha# isolate. One amino acid substitution of proline in GRO#alpha# by leucine in GRO#beta# and GRO#gamma# leads to a large predicted change in protein conformation. Significant differences also exist in the 3' untranslated region, including different numbers of ATTTA repeats associated with mRNA instability. A 122-base-pair region in the 3' region is conserved among the three GRO genes, and a part of it is also conserved in the Chinese hamster genome, suggesting a role in regulation. DNA hybridization with oligonucleotide probes and partial sequence analysis of the genomic clones confirm that the three forms are derived from related but ...

188

Fluid pressure arrival time tomography: Estimation and assessment in the presence of inequality constraints, with an application to a producing gas field at Krechba, Algeria  

Energy Technology Data Exchange (ETDEWEB)

Deformation in the overburden proves useful in deducing spatial and temporal changes in the volume of a producing reservoir. Based upon these changes we estimate diffusive travel times associated with the transient flow due to production, and then, as the solution of a linear inverse problem, the effective permeability of the reservoir. An advantage an approach based upon travel times, as opposed to one based upon the amplitude of surface deformation, is that it is much less sensitive to the exact geomechanical properties of the reservoir and overburden. Inequalities constrain the inversion, under the assumption that the fluid production only results in pore volume decreases within the reservoir. We apply the formulation to satellite-based estimates of deformation in the material overlying a thin gas production zone at the Krechba field in Algeria. The peak displacement after three years of gas production is approximately 0.5 cm, overlying the eastern margin of the ...

2010-04-01

189

First detection of lamella-gyroid-cylinder phase transition of neat polyethylene-poly(ethylene oxide) diblock copolymers on the basis of synchrotron WAXD/SAXS and infrared/Raman spectral measurements  

International Nuclear Information System (INIS)

The phase transition behaviour of polyethylene-b-poly(ethylene oxide) (PE-b-PEO) diblock copolymer with relatively short chain lengths has been studied on the basis of temperature dependent infrared and Raman spectral measurements and synchrotron WAXD/SAXS simultaneous measurements, from which the concrete structural changes were deduced successfully from the various levels of molecular chain conformation, chain packing mode and higher-order structure. The higher-order structure has been found to transform between lamella, perforated lamella, gyroid, cylinder and sphere structures. The inner structural changes occurring in the polyethylene and poly(ethylene oxide) parts have been related with these morphological changes. The morphological transition from lamella to gyroid occurs with keeping the crystalline state of polyethylene parts. This apparently curious transition can be interpreted reasonably by assuming the thermally-activated chain motion in the crystal ...

2009-08-01

190

Expression profiles of PtrLOS2 encoding an enolase required for cold-responsive gene transcription from trifoliate orange  

British Library Electronic Table of Contents (United Kingdom)

Low expression of osmotically responsive genes 2 (LOS2) encodes an enolase (2-phospho-D-glycerate hydrolase, EC 4.2.1.11) that converts 2-phospho-D-glycerate (PGA) to phosphoenolpyruvate (PEP) in the glycolytic pathway in Arabidopsis. Meanwhile, it is a transcriptional activator of cold-responsive gene, negatively controlling the expression of STZ/ZAT10, a zinc finger transcriptional repressor of cold-responsive gene from Arabidopsis. A novel LOS2 gene, designated PtrLOS2 (GenBank accession number GQ144341), was isolated from trifoliate orange [Poncirus trifoliata (L.) Raf.]. The PtrLOS2 cDNA is 1 662 bp in length with a 1 338 bp open reading frame (ORF), encoding a deduced 445 amino acid residue protein with a predicted molecular mass of 47.79 kDa and an isoelectric point of 5.54. The ded...

2011-01-01

191

Energetic electrons in impulsive and extended solar flares as deduced from flux correlations between hard X-rays and microwaves  

Energy Technology Data Exchange (ETDEWEB)

The peak flux relationship between hard X-rays and microwaves from solar flares is studied using about 400 events simultaneously recorded with the hard X-ray burst spectrometer on the SMM satellite and the Nobeyama 17 GHz radiometer. The data indicate that the hard X-ray and microwave peak fluxes correlate best for X-ray energies of less than about 80 keV for impulsive flares and greater than about 360 keV for extended flares. By postulating that electrons responsible for microwave emission at 17 GHz are those emitting hard X-rays at these photon energies, it is concluded that: (1) in impulsive flares, microwaves at about 20 GHz are emitted mainly by electrons of less than about 200 keV from a layer through which the electrons stream down into the thick-target hard X-ray source; and (2) in extended flares, microwaves are emitted mainly by MeV electrons trapped in a coronal loop or loops. 59 references.

1988-01-01

192

Effect of solute content on plasma nitriding behavior of Fe-Cr alloys; Fe-Cr gokin purazuma chikka kyodo ni oyobosu yoshitsu nodo no eikyo  

Energy Technology Data Exchange (ETDEWEB)

It has been clarified by the present authors, based on the plasma nitriding of Fe-Cr alloys and Fe-Ti alloys carried out at the temperature under 550{degree}C hitherto, that an internal nitriding layer is formed due to the fine dispersion of the particles of Cr nitride and Ti nitride in {gamma}{prime} Fe4N layer on the specimen surface. In this study, the plasma nitriding of Fe-Cr alloys are carried out at 650{degree}C, and the effects of the solute (Cr) content on the structures, nitride and the thickness distribution are examined. The main results obtained therefrom are indicated hereafter. In accordance with the observation on the cross-sectional structure of the alloys, only the nitriding layer deduced as the dispersion and precipitation of the particles of Cr nitride from {alpha}-Fe of the mother phase is formed, while {gamma}{prime}-Fe4N layer, which is found at the temperature under 550{degree}C, is not formed. The nitride of Cr generated in the nitriding ...

1996-03-15

193

Diffusion mechanism of implanted Be in GaAs  

Energy Technology Data Exchange (ETDEWEB)

The transient enhanced diffusion of low and high dose implanted beryllium in undoped gallium arsenide during post-implant rapid thermal annealing in the temperature range of 700-900 C for 60-240 s has been studied and successfully simulated by the kick-out diffusion model, involving singly positively charged Be interstitials and doubly positively charged Ga self-interstitials. Using the ''plus one'' approach for Ga interstitial generation after implantation with the local Ga interstitial sink concept as well as the appropriate initial and boundary conditions for involved mobile species, and taking into account Fermi-level and built-in electric field effects, the obtained partial differential equations have been solved numerically by means of an explicit finite difference method. The thermal equilibrium concentrations and the diffusivities of Be and Ga interstitials, all as a function of temperature, have been deduced from the ...

2008-01-15

194

Development of the Regulation Concept for a Fusion Reactor  

International Nuclear Information System (INIS)

Fusion energy has been studied in many countries such as U.S., France, Japan, Korea etc. Because it would provide much more energy for a given weight of fuel than any technology currently in use, and the fuel itself (primarily deuterium) exists abundantly in the Earth's ocean. Nuclear fusion reactor uses tritium and deuterium as fuel while nuclear fission reactor uses uranium and plutonium as fuel. Besides, inherent design characteristics and driving condition of nuclear fusion reactor is different from those of nuclear fission reactor. Therefore, we cannot apply the regulation rules of nuclear fission reactor to nuclear fusion reactor without change and thus it is needed to development of the safety regulation concept which reflects the characteristics of nuclear fusion reactor. Safety regulation of nuclear fusion reactor employs deterministic approach until sufficient data are secured. However, regulation methodology of nuclear fusion reactor should be based on risk-informed ...

2010-10-01

195

Determination of the emission zone in a single-layer polymer light-emitting diode through optical measurements  

Science.gov (United States)

We study the emission zone in a single-layer polymer light-emitting diode. The emission zone is found by studying the angular distribution of the electroluminescence. The emission is modeled by accounting for optical interference. We account for birefringence of the anode layer in our model. The active polymer was, however, found to be isotropic. The anode consists of a single-layer of the conducting polymer complex poly(3,4-ethylenedioxythiophene) and poly(styrene sulfonate) (PEDOT-PSS), with enhanced conductivity. As a cathode we use plain aluminum. By using only PEDOT-PSS we avoid having a thin metal layer or indium-tin-oxide as the anode in the path of the escaping light. The active material is a substituted polythiophene with excellent film forming properties. A comparison between the experimental and calculated angular distribution of light emission from a single-layered polymer light-emitting diode was shown to be in good agreement for the spectral region studied. By assuming a ...

2001-06-01

196

Design and performance of a solar-powered air-conditioning system in a green building  

Energy Technology Data Exchange (ETDEWEB)

A solar-powered adsorption air-conditioning system was designed and installed in the green building of Shanghai Research Institute of Building Science. The system contained 150 m{sup 2} solar collectors and two adsorption chillers with nominal refrigeration capacity of 8.5 kW. Based on performance characteristics of the adsorption chiller, the operation mode of the solar-powered air-conditioning system was optimized by maintaining a phase shift of 540 s between the two adsorption chillers. Thereafter, the whole system realized stable operation by the balance of heat consumption and refrigeration output. From June to August of 2005, the solar-powered air-conditioning system continuously ran between 9:00 and 17:00. The operation performance of the system under representative working condition showed that the average refrigeration output of the solar-powered air-conditioning system was 15.3 kW during an 8 h operation and the maximum value exceeded 20 kW. Solar fraction for the system in ...

2008-05-15

197

Contribution to the study of sputtering and damage of uranium dioxide by fast heavy ions; Contribution a l'etude de la pulverisation et de l'endommagement du dioxyde d'uranium par les ions lourds rapides  

Energy Technology Data Exchange (ETDEWEB)

Swift heavy ion-solid interaction leads in volume to track creation and on the surface to the ejection of particles into the vacuum. To learn more about initial mechanisms of track formation, we are focused on the sputtering of uranium dioxide by fast heavy ions. This present study is exclusively devoted to the influence of the electronic stopping power on the emission of neutral particles and especially on their angular distribution. These measurements are completed by those of the ions emitted from UO{sub 2} targets bombarded with swift heavy ions. The whole experimental results give access to: i) the nature of the sputtered particles; ii) the charge state of the emitted particles; iii) the direction of ejection of the sputtered particles ; iv) the sputtering yields deduced from the angular distributions. These results are compared to the prediction of the sputtering models proposed in the literature and it seems that the supersonic gas flow model is well suited ...

2001-03-01

198

Compound elastic cross sections in the isobaric analog resonances /sup 88/Sr(p,p/sub 0/) at 5. 06 MeV and /sup 86/Sr(p,p/sub 0/) at 6. 02 MeV  

Energy Technology Data Exchange (ETDEWEB)

We have measured the K-shell ionization probability Psub(K) across the isobaric analog resonances in the elastic channel of the reactions /sup 88/Sr(p, p/sub 0/)/sup 88/Sr at 5.06 MeV and /sup 86/Sr(p, p/sub 0/)/sup 86/Sr at 6.02 MeV. The dependence of Psub(K) on the beam energy for two scattering angles 90/sup 0/ and 155/sup 0/ is analysed in the framework of the theory developed by Anholt et al. taking into account the effect of compound-nucleus scattering. A compound elastic cross section (dsigma/d..cap omega..)sub(CE)=40+-10 mb/se at the peak of the resonance is deduced in the reaction /sup 88/Sr+p at 5.06 MeV, while the experimental results agree with a negligible value of (dsigma/d..cap omega..)sub(CE) for the resonance in /sup 86/Sr+p at 6.02 MeV.

1983-10-27

199

Compound elastic cross sections in the isobaric analog resonances "8"8Sr(p,p_0) at 5.06 MeV and "8"6Sr(p,p_0) at 6.02 MeV  

International Nuclear Information System (INIS)

We have measured the K-shell ionization probability Psub(K) across the isobaric analog resonances in the elastic channel of the reactions "8"8Sr(p, p_0)"8"8Sr at 5.06 MeV and "8"6Sr(p, p_0)"8"6Sr at 6.02 MeV. The dependence of Psub(K) on the beam energy for two scattering angles 90"0 and 155"0 is analysed in the framework of the theory developed by Anholt et al. taking into account the effect of compound-nucleus scattering. A compound elastic cross section (dsigma/d#OMEGA#)sub(CE)=40+-10 mb/se at the peak of the resonance is deduced in the reaction "8"8Sr+p at 5.06 MeV, while the experimental results agree with a negligible value of (dsigma/d#OMEGA#)sub(CE) for the resonance in "8"6Sr+p at 6.02 MeV. (orig.).

200

Common Origin of mu-tau and CP Breaking in Neutrino Seesaw, Baryon Asymmetry, and Hidden Flavor Symmetry  

CERN Document Server

We conjecture that all CP violations (both Dirac and Majorana types) arise from a common origin in neutrino seesaw. With this conceptually attractive and simple conjecture, we deduce that mu-tau breaking shares the common origin with all CP violations. We study the common origin of mu-tau and CP breaking in the Dirac mass matrix of seesaw Lagrangian (with right-handed neutrinos being mu-tau blind), which uniquely leads to inverted mass-ordering of light neutrinos. We then predict different correlations between the two small mu-tau breaking observables theta_{13} - 0 and theta_{23} -45, which can be tested against our previous normal mass-ordering scheme by the on-going oscillation experiments. We also analyze the correlations of theta_{13} with Jarlskog invariant and neutrinoless double-beta-decay observable. From the common origin of CP and mu-tau breaking in the neutrino seesaw, we establish a direct link between the low energy CP violations and the cosmological ...

2011-01-01

201

Cloning and expression of a human kidney cDNA for an /alpha//sub 2/-adrenergic receptor subtype  

Energy Technology Data Exchange (ETDEWEB)

An /alpha//sub 2/-adrenergic receptor subtype has been cloned from a human kidney cDNA library using the gene for the human platelet /alpha//sub 2/-adrenergic receptor as a probe. The deduced amino acid sequence resembles the human platelet /alpha//sub 2/-adrenergic receptor and is consistent with the structure of other members of he family of guanine nucleotide-binding protein-coupled receptors. The cDNA was expressed in a mammalian cell line (COS-7), and the /alpha//sub 2/-adrenergic ligand (/sup 3/H)rauwolscine was bound. Competition curve analysis with a variety of adrenergic ligands suggests that this cDNA clone represents the /alpha//sub 2/B-adrenergic receptor. The gene for this receptor is on human chromosome 4, whereas the gene for the human platelet /alpha//sub 2/-adrenergic receptor (/alpha//sub 2/A) lies on chromosome 10. This ability to express the receptor in mammalian cells, free of other adrenergic receptor subtypes, should help in developing more ...

1988-09-01

202

Can a model-independent analysis be made for the matter distribution of "4"0Ca from 166 MeV #alpha# particle scattering  

International Nuclear Information System (INIS)

It is proposed to extract, independently of any nuclear model, the "4"0Ca matter density from an analysis of the elastic scattering of "1"6"6 MeV alpha particles. The scattering is described using an optical potential whose real part is evaluated by folding the matter density with a nucleon-alpha interaction. Following the procedure proposed by Sick (Nucl. Phys. A; 218: 509 (1974)) and Phys. Lett.; 44B; 62 (1975)) for the analysis of electron scattering data, the density is represented by a sum of gaussians whose amplitudes are deduced in fitting, via a chi"2 minimization, the experimental cross section data. This method determines the envelope of densities for different parameters of gaussians: width, spacing. The envelope of the moments of these densities are presented and the root-mean-square radius is extracted. It is concluded that only the nuclear surface is well studied by the alpha particle scattering. (author).

203

Analysis of the relation between "3H concentrations in sea water of West Daya Bay and GNP's liquid "3H discharges  

International Nuclear Information System (INIS)

Through the analysis of the relations between "3H monitoring results of sea water in West Daya Bay carried out by Guangdong Environmental Radiation Research and Monitoring Center (GERC) from 1994 to 2000 and the quantity of liquid "3H discharges made by Guangdong Nuclear Power Station (GNPS), the function has been found by fitting to describe the relation between "3H average concentrations (hereafter as to average concentration or concentration) for all sampling points at the same time and the quantity of liquid "3H discharges. "3H instantaneous concentrations or yearly average concentration in West Daya Bay can be estimated conveniently by using this function corresponding to either actual discharges or supposed discharges (the way for hydrodynamic calculation) from the GNPS's yearly "3H liquid discharge. The results have shown that the general influences both actual discharges and supposed sub-continuous discharges are almost the same and this results are in good agreement with the ...

2001-11-01

204

Amount of confining reinforcement required for flexural ductility of reinforced concrete columns. Tekkin concrete chu buzai no mage jinsei to yokokosoku (confined) hokyo kinryo  

Energy Technology Data Exchange (ETDEWEB)

In this paper, an amount of confining reinforcement required for the sufficient flexural ductility of reinforced concrete column was investigated. An equation to calculate the required confining reinforcement ratio was deduced from the analytical investigation and examination on the previous experimental data as to the effects of various factors on the required confining reinforcement ratio. The rotation angle required in plastic hinges, the axial force ratio, the material properties such as concrete strength, and the ratio of core area to the whole area of column sections were employed as the factors. From the examination of the equation, it was shown that the ultimate rotation in plastic hinges calculated by the equation was more conservative than the ultimate rotaion angle of members obtained by test column specimens. It was also indicated that the ultimate rotation angle of members of columns failed in shear was smaller than the ultimate rotation in plastic ...

1991-09-15

205

A Wide-Band Electromagnetic Impedance Profiling System forNon-Invasive Subsurface Characterization  

Energy Technology Data Exchange (ETDEWEB)

A non-invasive, wide-band electromagnetic (EM) impedance difference system for shallow subsurface electrical structure characterization in environmental and engineering problems has been developed at the Lawrence Berkeley National Laboratory (LBNL). Electrical parameters of interest are electrical conductivity and dielectric permittivity that are deduced from the impedance difference data. The prototype system includes a magnetic loop transmitter, which operates between 0.1 MHz and 100 MHz, an electrical dipole antenna for observing the electric field, and a loop antenna for measuring the magnetic field.All antennas are mounted on a cart made of non-metallic material for easy movement of the whole array for profiling. Surface EM impedance difference is obtained by taking the difference of the ratios of the electric fields to the magnetic fields at selected frequencies at two different levels. Numerical simulations will be presented to verify this new approach. A ...

2004-12-17

206

The Aldous-Shields model revisited (with application to cellular ageing)  

CERN Document Server

In Aldous and Shields (1988), a model for a rooted, growing random binary tree was presented. For some c>0, an external vertex splits at rate c^(-i) (and becomes internal) if its distance from the root (depth) is i. For c>1, we reanalyse the tree profile, i.e. the numbers of external vertices in depth i=1,2,.... Our main result are concrete formulas for the expectation and covariance-structure of the profile. In addition, we present the application of the model to cellular ageing. Here, we assume that nodes in depth h+1 are senescent, i.e. do not split. We obtain a limit result for the proportion of non-senescent vertices for large h.

2010-01-01

207

Search for extended conformal algebra  

International Nuclear Information System (INIS)

The authors search for the extended conformal algebra with two spin-s (s:integer) and one spin-1 generators. This search is inspired by the existence of chiral algebra in the Gaussian model for rational radius. For odd s, the conformal properties of the three-point functions imply that a general fusion rule can be reduced to those of the Gaussian model. For arbitrary even s, these conditions are weaker. In particular, for s = 2 the authors show that the chiral algebra of the Gaussian model is the unique extended conformal algebra with the value of the central charge fixed to be c = 1. It is also shown that the conformal generator is necessarily a bilinear of the spin-1 generator just as the Gaussian model. The authors conjecture that this remains true for arbitrary value of s.

1990-08-01

208

Radiopharmaceuticals labelled with positron emitting radionuclides  

International Nuclear Information System (INIS)

A brief survey is presented of the methods of preparation and of the applications of radiopharmaceuticals labelled with short-lived positron radionuclides "1"1C, "1"8F, "1"3N and "1"5O which, thanks to their energy level schemes, short half-life and the 511 keV photon radiation energy are almost ideal tracers in modern nuclear medicine and pharmacology. In conjunction with computerized tomography, they represent one of the most sensitive diagnostic imaging methods, the so-called positron emission tomography. In addition, their incorporation in the molecule of a pharmaceutical does not change the biological and chemical properties of the original molecule unlike those of radiopharmaceuticals labelled with technetium, iodine, etc. (author). 125 refs.

1989-01-01

209

Pyrolysis of spill oils adsorbed on zeolites with product oils recycling  

International Nuclear Information System (INIS)

Experimentally, a feasibility study for adsorption and catalytic pyrolysis of spill oils on Cu/ZSM-5 for recycling of light oils has been conducted in the present work. The adsorption and pyrolysis of model compounds such as heptane, toluene, and diesel (to stimulate the spill oils) on Cu/ZSM-5 have been investigated on a continuous fixed-bed reactor. By component fitted X-ray absorption near edge structural (XANES) spectroscopy, catalytic active species such as metallic copper (Cu) (77-84%) and Cu2O (6-7%) are found in the channels of ZSM-5 during pyrolysis of heptane or toluene. Pyrolysis of diesel effected by Cu/ZSM-5 yields gas (C1-C5) (32%) and light oil (68%) that can be used as auxiliary fuels.

2007-06-03

210

Polarised neutron reflectometry study of Co/CoO exchange-biased multilayers  

Energy Technology Data Exchange (ETDEWEB)

We have investigated via SQUID magnetometry and polarised neutron reflectivity the exchange-bias effect in CoO/Co sputtered multilayers. In particular, we studied the magnetisation reversal and the time relaxation of the exchange-bias field close to the coercive field H{sub c1}. Neutron intensities of all four cross sections (I++, I+-, I-+, I-) were recorded at the position of the first multilayer Bragg peak while scanning the magnetic field. From such scans we infer that the magnetisation reversal for the ascending as well as for the descending branch of the magnetic hysteresis occurs not by in-plane rotation but through domain-wall movements. The exchange-bias field, H{sub EB}, is strongly affected by thermal fluctuations. H{sub EB} decreases, following an exponential decay function with a half-life time of about 580 s at T=240 K. (orig.)

2002-07-01

211

On the relation between the superconducting transition temperature Tsub(c) and the electron-per-atom ratio, e/a, in the A-15 compounds  

International Nuclear Information System (INIS)

The authors make two points. Firstly, they emphasise that while the correlation suggested by the B.C.S. formula, Tsub(c) = 1.14 thetasub(D) exp[-1/n(Esub(F))V], between Tsub(c) and the density of states at the Fermi energy, N(Esub(F)), appears to coincide with the empirical trends, this agreement is purely fortuitous. Such a correlation is due to the influence of N(Esub(F)) on the phonon frequencies, which in turn determine the strength of the electron-phonon coupling. Secondly, they point out that their analysis, which was developed for transition metals, is directly applicable to the A-15 compounds leading to results in agreement with the work of Fradin et al. (Auth.).

212

Non-relativistic Fermions, Coadjoint Orbits of \\winf\\ and String Field Theory at $c=1$  

CERN Document Server

We apply the method of coadjoint orbits of \\winf-algebra to the problem of non-relativistic fermions in one dimension. This leads to a geometric formulation of the quantum theory in terms of the quantum phase space distribution of the fermi fluid. The action has an infinite series expansion in the string coupling, which to leading order reduces to the previously discussed geometric action for the classical fermi fluid based on the group $w_\\infty$ of area-preserving diffeomorphisms. We briefly discuss the strong coupling limit of the string theory which, unlike the weak coupling regime, does not seem to admit of a two dimensional space-time picture. Our methods are equally applicable to interacting fermions in one dimension.

1992-01-01

213

High-field magnetization of CeRh{sub 2}Si{sub 2} and CePd{sub 2}Si{sub 2}  

Energy Technology Data Exchange (ETDEWEB)

High-field magnetization properties of single crystalline CeRh{sub 2}Si{sub 2} and CePd{sub 2}Si{sub 2} were investigated. Two-step metamagnetic transition (H{sub c1}=25.4 T and H{sub c2}=26.0 T) was observed in the case of CeRh{sub 2}Si{sub 2}, whereas no anomaly was found in the magnetization process of CePd{sub 2}Si{sub 2} up to 28 T. The mean field analysis has shown that CeRh{sub 2}Si{sub 2} is quite anisotropic compared to CePd{sub 2}Si{sub 2}, which results in the sharp contrast between the magnetization processes of the two compounds.

1998-07-01

214

High-field magnetization of CeRh_2Si_2 and CePd_2Si_2  

International Nuclear Information System (INIS)

High-field magnetization properties of single crystalline CeRh_2Si_2 and CePd_2Si_2 were investigated. Two-step metamagnetic transition (H_c_1=25.4 T and H_c_2=26.0 T) was observed in the case of CeRh_2Si_2, whereas no anomaly was found in the magnetization process of CePd_2Si_2 up to 28 T. The mean field analysis has shown that CeRh_2Si_2 is quite anisotropic compared to CePd_2Si_2, which results in the sharp contrast between the magnetization processes of the two compounds

1997-08-04

215

Evaluation technique of neutron-irradiation embrittlement in welded RPV  

International Nuclear Information System (INIS)

The ductile-brittle transition behavior of neutron-irradiated welded A533B C1.1 steel has been studied by means of small specimen test technique for discussing the specimen size effects on the impact properties. Standard size, one-third size and 1.5 mm size Charpy V-notch specimens were prepared. Neutron irradiation was performed in JMTR with fluencies up to 0.75 and 1.3x10"2"4 n/m"2 (E > 1 MeV). Normalization of the USE is done by a curve fitting method and the USE of different size of specimens can be expressed by the equation; E=a x B"n, where a is a constant and n is an exponent. There observed linear relationships between DBTTs obtained using standard and sub-sized specimens. (author)

2006-07-01

216

Diode laser overtone spectroscopy of CO_2 at 780nm  

International Nuclear Information System (INIS)

Overtone absorption lines of "1"2C"1"6O_2 have been examined by using a tunable diode laser (TDL) spectrometer in the region around 12770cm"-"1. The spectrometer sources are commercially available double heterostructure InGaAlAs TDLs operating in the 'free-running' mode, which allowed the detection of the line positions within 0.01cm"-"1. The observed carbon dioxide absorption lines belong to the #nu#_1+5#nu#_3 ro-vibrational band with rotational quantum number J up to 48. The minimum absorbance detected by the spectrometer (#approx#5x10"-"6) permitted to observe the weakest lines having the absorption cross section of the order of #approx#1x10"-"2"7cm"2/molecule.

2005-12-01

217

Determination of molar extinction coefficients #epsilon#_m(Ce"4"+) of Ce"4"+-Ce"3"+ dosimetric system  

International Nuclear Information System (INIS)

#epsilon#_m(Ce"4"+) values of the ceric-cereus system have been measured and the experimental procedure is described. Both routine titration method and electrochemical measurement were used. Some interference factors, such as ultraviolet, acidity and temperature, were studied as well. The temperature coefficient of #epsilon#_m(Ce"4"+) value in this experiment is about -0.1% degree C"-"1. A statistic analysis was made for 24 experimental values of #epsilon#_m(Ce"4"+) and a Gaussian distribution was found. Ultimately, an average molar extinction coefficient of 553.2 +- 1.3 m"2#centre dot#mol"-"1 was obtained at #approx#320 nm in 0.4 mol/L H_2SO_4 system, with a relative standard deviation of 0.24% (95% confidence level) and a total uncertainty of 1.5%.

1996-01-01

218

BRE: Consultation on the Green Guide update  

Wastenet

...Content 3a LCA Methodology - Characterisation(PDF) 3a1 BRE Response - Characterisation 3b LCA Methodology - Normalisation (PDF) 3b1 BRE Response - Normalisation 3c LCA Methodology - Weighting (PDF) 3c1 Feedback - Weighting 3c2 Weightings Exercise (PDF) 4 Specification (PDF) 4a - Functional Units Spreadsheet (Excel) 4b Specification List (Excel) 5 Energy Model (PDF) 6 Whole Life perfomance 6b Response Note To Briefing Note 6 - Whole Life Performance (PDF) 7 End-of-Life and Waste models (PDF) 7a Waste routes and rates feedback (PDF) 7b Waste Disposal Routes for Industry Consultation 7c Site Wastage Rates for Industry Consultation 8 Existing LCA ...

219

Analysis by radio-gaschromatography of volatile aldehydes produced by the linoleic acid oxidation of soya- and oats-lipoxygenase  

International Nuclear Information System (INIS)

Soya- and oats-lipoxygenase (E.C. 1.13.1.13) are incubated by "1"4C-marked linoleic acid. The volatile aldehydes arising thereby are isolated. The activity of the components separated by gaschromatography is written down by a printing indicator and the impulses/min are registered and printed out by a ratemeter. Thus the aldehydes which are produced by the enzymatic oxydation with lipoxygenase from the molecule of the linoleic acid can be determined. The composition of the mixture of aldehydes is calculated in mol-% from the measured impulses for peak. A possible origin of pathway is indicated for the main reaction products hexanal (soyalipoxygenase) and non-trans-2-enal (oats-lipoxygenase). (orig.).

220

The neurotoxic effects of artemether on the cytoarchitecture of the cerebellum of adult male wistar rats  

International Nuclear Information System (INIS)

In a 70kg adult man, artemether is given at a total dosage of 480mg for five days in the treatment of malarial. Using t-test analysis technique at 95% confidence interval i.e t < 0.05 and P - value = 2.26, no significant difference was observed between the average brain and cerebellar weight, the average width of cerebellar cortical layers, the density and the average size of Purkinje Cells in the control groups C1 and C2 and the experimental group E. In the present study, there were no gross or morphological differences between the two groups of animals (control and experimental groups) on day 7 at the completion of experimental procedure. A significant statistical increase in average body weight was observed in the control groups C1 (which received only standard diet and water) and C2 (which received 1.23mg/kg body weight of normal saline intramuscularly in addition to standard diet and water) from ...

2007-01-01

221

Simultaneous production of "2"8Mg and "4"7Ca by high-energy heavy-ion irradiation for applications in biology  

International Nuclear Information System (INIS)

With the aim of preparing carrier-free "2"8Mg and "4"7Ca simultaneously, Ti, V and Fe targets were examined by irradiating with high-energy ions of "1"2C, "1"4N and "1"6O accelerated by the RIKEN ring cyclotron. Among the targets, V gave the highest cross section for the formation of both "2"8Mg and "4"7Ca irrespective of the kind of beams. The cross section for the formation of "2"8Mg by the reactions of Ti, V and Fe targets with ion beams increased in the order of "1"2C<"1"6O<"1"4N. On the other hand, the three beams exhibited almost the same cross sections for the formation of "4"7Ca by the reaction of a given target. Titanium and V were selected as prospective targets and "1"4N as a suitable beam for the production of "2"8Mg and "4"7Ca. Chemical separation procedures of the radiotracers in carrier- and salt-free states have been established by using cation exchange resins. The recovery yields ...

222

Preoperative staging of rectal carcinoma with combined sonography and pelvic computed tomography  

International Nuclear Information System (INIS)

The accurate staging of rectal carcinoma is very important for treatment planning. The histological data obtained from surgical specimens of 22 patients with rectal carcinoma were compared with pre-and postoperative endorectal US findings and with preoperative CT results. According to an adapted version of Astler and Coller classification, the different degrees of tumor spread into the rectal wall were represented as follows: stage A: 1 patient; stage B1: 5 patients; stage B2: 6 patients; stage C1: 1 patient; stage C2: 8 patients and stage D: 1 patient. Preoperative staging, based on the overall results of CT and US, was in agreement with histology in 19 of 22 cases. Individual analysis of US and CT results, in comparison with histological data, showed US staging accuracy to be 77.3% (17/22 patients). US accuracy in demonstrating tumor spread into the rectal wall (stages A, B1, C1) was 100% (7/7 ...

1991-01-01

223

Observation of eta_c(1S) and eta_c(2S) decays to K+ K- pi+ pi- pi0 in two-photon interactions  

CERN Document Server

We study the processes gamma gamma -> K^0_S K+/- pi-/+ and gamma gamma -> K+ K- pi+ pi- pi0 using a data sample of 519.2 fb-1 recorded by the BaBar detector at the PEP-II asymmetric-energy e+e- collider at center-of-mass energies near the Upsilon(nS) (n = 2,3,4) resonances. We observe the eta_c(1S), chi_c0(1P), chi_c2(1P), and eta_c(2S) resonances produced in two-photon interactions and decaying to K+ K- pi+ pi- pi0, with significances of 18.1, 5.7, 5.2, and 5.3 standard deviations (including systematic errors), respectively. We measure the eta_c(2S) mass and width in K^0_S K+/- pi-/+ decays, m(eta_c(2S))=3638.5 +/- 1.5 +/- 0.8 MeV/c^2 and Gamma(eta_c(2S)) = 13.4 +/- 4.6 +/- 3.2 MeV, where the first uncertainty is statistical and the second is systematic. We search for the Z(3930) resonance and find no significant signal. We also provide the two-photon width times branching fraction values for the observed resonances.

2011-01-01

224

Next-to-leading-order QCD correction to inclusive J/#psi#(#UPSILON#) production in Z"0 decay  

International Nuclear Information System (INIS)

In this paper, we study the J/#psi#(#UPSILON#) production in Z boson decay in a color-singlet model (CSM). We calculate the next-to-leading-order (NLO) QCD correction to Z#->#quarkonium+QQ, the dominant contribution in the CSM, with the vector and axial-vector parts in the ZQQ vertex being treated separately. The results show that the vector and axial-vector parts have the same K factor (the ratio of the NLO result to the leading-order result) 1.13 with the renormalization scale #mu#=2m_c and m_c=1.5 GeV, and the K factor falls to 0.918 when applying the Brodsky, Lepage, and Mackenzie (BLM) renormalization scale scheme with obtained #mu#_B_L_M=2.28 GeV and m_c=1.5 GeV. By including the contributions from the next-dominant ones, the photon and gluon fragmentation processes, the branching ratio for Z#->#J/#psi#_p_r_o_m_p_t+X is (7.3-10.0)x10"-"5 with the uncertainty consideration for the ...

2010-09-01

225

Magnetic and thermal properties of cubic single-crystal PrCu_4Ag  

International Nuclear Information System (INIS)

We succeeded in synthesizing a new cubic intermetallic compound PrCu_4Ag in a fcc structure. Measurements of X-ray diffraction, magnetic susceptibility, magnetization, specific heat, electrical resistivity, thermal expansion, and elastic constants have been performed on single crystals of PrCu_4Ag. A maximum value of #chi#(T) with a corresponding peak in C(T) suggests that an antiferromagnetic phase transition occurs at T_N=2.4 K, where a sudden decrease in #rho#_4_f(T) and a sharp peak in the thermal expansion coefficient #alpha#(T) were observed. Characteristic Curie-type softening was observed in the temperature dependence of the transverse mode for (C_1_1 - C_1_2)/2 and C_4_4 from 70 K down to T_N, which implies that the crystalline electric field (CEF) ground state is the magnetic triplet #GAMMA#_5. The anisotropic properties in M(T,H) and C(T,H) are studied when the external magnetic field is ...

2010-11-01

226

High-precision Penning-Trap measurements of light-ion masses  

International Nuclear Information System (INIS)

The UW-Penning Trap Mass Spectrometer (PTMs) is ideally suited for high precision measurements of atomic masses throughout the periodic table upon using highly-stripped ions. However, at the present time, this device has been applied extensively to the light elements ("1H, "2H, "3H, "3He, "4He, "1"2C, "1"3C, "1"4N, "1"6O) due to their fundamental importance. Atomic masses follow immediately from a comparison with some multiply-charged carbon ion, after correcting for the lost electrons and their corresponding binding energies. For instance, the most recent C"5"+/C"6"+ comparison yielded a discrepancy of -0.30(33) ppb, limited only by the magnetic field instability for a 40-h run. The initial emphasis on hydrogen has now produced a 1-ppb value for the proton's atomic mass and similar work with deuterium has yielded a 2.5-ppb value for the neutron's atomic mass. However, the most significant result is the ...

1993-04-12

227

Galactic evolution of D and "3He including stellar production of "3He  

International Nuclear Information System (INIS)

New stellar models which track the production and destruction of "3He (and D) have been evolved for a range of stellar masses (0.65#<=#M/M_c_i_r_c_l_e_-_d_o_t#<=#100), metallicities (0.01#<=#Z/Z_c_i_r_c_l_e_-_d_o_t#<=#1), and initial (main-sequence) "3He mass fractions (10"-"5#<=#X_3_,_M_S#<=#10"-"3). Armed with the "3He yields from these stellar models we have followed the evolution of D and "3He using a variety of chemical evolution models with and without infall of primordial or processed material. Production of new "3He by the lower mass stars overwhelms any reasonable primordial contributions and leads to predicted abundances in the presolar nebula and/or the present interstellar medium in excess of the observationally inferred values. This result, which obtains even for zero primordial D and "3He, and was anticipated by Rood, Steigman, ampersand Tinsley is insensitive to the choice of chemical evolution model; it is driven by the large "3He yields from low-mass ...

228

Effect of salt stress and phosphorus deficiency in mutants of rhizobium obtained by gamma irradiation  

International Nuclear Information System (INIS)

Two strains of Rhizobium: Rhizobium Tropici and Mesorhizobium Ciceri nodulating respectively common bean and chickpea were treated by gamma irradiation (60Co) source. Radiosensibility analysis showed that 800 Gy was the biggest dose supported by these two strains. We isolated gamma irradiated resistant strain in order to select mutant of them which can supported salt stress and phosphorus deficiency. Salinity analysis showed that Mesorhizobium Ciceri 835 strain, can tolerate up to 18g/l (273 mM NaCl) of salt, whereas, their irradiation mutants tolerate salinity up to 33g/l (564mM. NaCl) Rhizobium Tropici CIAT899 can survive at 20g/l (342 mM) either for control strain or mutants. Analysis of phosphorus deficiency showed that either Rhizobium Tropici CIAT899, or Mesorhizobium Ciceri 835 can survive in medium without phosphore. Our results permit us to screen mutants tolerant to these stresses wide spread in Mediterranean soil. In this study, we choose two mutants strains irradiated by ...

2008-08-12

229

Heated lipiodol as an embolization agent for transhepatic arterial embolization in VX2 rabbit liver cancer model  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To evaluate the therapeutic effect of heated (60 deg. C) lipiodol via hepatic artery administration in a rabbit model of VX2 liver cancer. Materials and methods: Thirty male New Zealand white rabbits were randomly divided into three groups with 10 rabbits assigned to each group. VX2 carcinoma cells were surgically implanted into the left hepatic lobe. The tumors were allowed to grow for 2 weeks, and studies were performed until the diameter of the tumors detected by ultrasonograph reached 2-3 cm. Under anesthesia, trans-catheter hepatic arterial embolization was performed and doxorubicin-lipiodol (37 deg. C) (1 mL), lipiodol (60 deg. C) (1 mL) or control (physiological saline (37 deg. C) (1 mL)) solution was injected into the hepatic arteries of animals in the three groups. One week later, the volume of the tumor was measured by ultrasonograph again. ...

2010-02-15

230

{sup 48}Ti(n,xnpa{gamma}) reaction cross sections using spallation neutrons for E{sub n} = 1 to 20 MeV  

Energy Technology Data Exchange (ETDEWEB)

{gamma}-ray excitation functions have been measured for the interaction of fast neutrons with {sup 48}Ti (neutron energy from 1 MeV to 250 MeV). The Los Alamos National Laboratory spallation neutron source, at the LANSCE/WNR facility, provided a ''white'' neutron beam which is produced by bombarding a natural W target with a pulsed proton beam. The prompt-reaction {gamma} rays were measured with the large-scale Compton-suppressed Ge spectrometer, GEANIE. Neutron energies were determined by the time-of-flight technique. Excitation functions were converted to partial {gamma}-ray cross sections, taking into account the dead-time correction, the target thickness, the detector efficiency, and neutron flux (monitored with an in-line fission chamber). The data analysis is presented here for neutron energies between 1 to 20 MeV. Partial {gamma}-ray cross sections for transitions in {sup 47,48}Ti, {sup 48}Sc, and {sup 45}Ca have been determined. These results ...

2005-01-06

231

cDNA sequence analysis of a 29-kDa cysteine-rich surface antigen of pathogenic Entamoeba histolytica  

Energy Technology Data Exchange (ETDEWEB)

A {lambda}gt11 cDNA library was constructed from poly(U)-Spharose-selected Entamoeba histolytica trophozoite RNA in order to clone and identify surface antigens. The library was screened with rabbit polyclonal anti-E. histolytica serum. A 700-base-pair cDNA insert was isolated and the nucleotide sequence was determined. The deduced amino acid sequence of the cDNA revealed a cysteine-rich protein. DNA hybridizations showed that the gene was specific to E. histolytica since the cDNA probe reacted with DNA from four axenic strains of E. histolytica but did not react with DNA from Entamoeba invadens, Acanthamoeba castellanii, or Trichomonas vaginalis. The insert was subcloned into the expression vector pGEX-1 and the protein was expressed as a fusion with the C terminus of glutathione S-transferase. Purified fusion protein was used to generate 22 monoclonal antibodies (mAbs) and a mouse polyclonal antiserum specific for the E. histolytica portion of the fusion protein. ...

1990-08-01

232

cDNA sequence analysis of a 29-kDa cysteine-rich surface antigen of pathogenic Entamoeba histolytica  

International Nuclear Information System (INIS)

A #lambda#gt11 cDNA library was constructed from poly(U)-Spharose-selected Entamoeba histolytica trophozoite RNA in order to clone and identify surface antigens. The library was screened with rabbit polyclonal anti-E. histolytica serum. A 700-base-pair cDNA insert was isolated and the nucleotide sequence was determined. The deduced amino acid sequence of the cDNA revealed a cysteine-rich protein. DNA hybridizations showed that the gene was specific to E. histolytica since the cDNA probe reacted with DNA from four axenic strains of E. histolytica but did not react with DNA from Entamoeba invadens, Acanthamoeba castellanii, or Trichomonas vaginalis. The insert was subcloned into the expression vector pGEX-1 and the protein was expressed as a fusion with the C terminus of glutathione S-transferase. Purified fusion protein was used to generate 22 monoclonal antibodies (mAbs) and a mouse polyclonal antiserum specific for the E. histolytica portion of the fusion protein. ...

233

X-ray absorption spectroscopy of bacterial sulfur globules  

Energy Technology Data Exchange (ETDEWEB)

Sulfur K-edge X-ray absorption spectroscopy is a powerful in situ probe of sulfur biochemistry in intact cells and tissues. Under favorable circumstances the technique can provide quantitative information on the chemical identify of the sulfur species that are present in a sample. Prange et al. have recently reported an X-ray absorption spectroscopic study of bacterial sulfur storage globules. Unfortunately there are substantial problems with the experimental technique employed that, they contend, lead to completely erroneous conclusions. In the more recent of their two papers Prange et al. employed a curve-fitting method similar to that used by us (for more than 10 years). In essence, the method employs simply fitting a linear combination of the spectra of standard compounds to that of the unknown, in this case cultures of bacterial cells. This type of analysis can provide quantitative estimates of the individual sulfur types in the sample, but is critically dependent upon the choice ...

2002-08-01

234

The carbonate feedback system: interaction between stratigraphic accommodation, ecological succession and the carbonate factory; Le systeme de feed-back des carbonates: une interaction entre accomodation stratigraphique, succession ecologique et l`usine des carbonates  

Energy Technology Data Exchange (ETDEWEB)

In this paper, the analysis of carbonate depositional systems, using high resolution sequence stratigraphy, studies the ratio between change in accommodation space and skeletal carbonate production. This approach establishes the concurrent change in nature of facies belts (expansion, retraction and type) and fossil communities, within the detailed time frame in accommodation. Carbonate production is generally considered to be a fairly simple function of environmental conditions such as climate and water depth. However, data from several case studies also show a covariance between change in stratigraphic architecture of carbonate systems (the seaward or landward stepping stacking patterns of stratigraphic units) and charge in facies. Case studies include Carboniferous algal mound development in the Paradox Basin (USA), Devonian stromatoporoid reef development in Alberta (Canada), and Cenomanian rudistid shoal development in Oman. The hypotheses are tested on cases taken from the ...

1996-12-31

235

Study of ytterbium doping effects on structural, mechanical and opto-thermal properties of sprayed ZnO thin films using the Boubaker Polynomials Expansion Scheme (BPES)  

Energy Technology Data Exchange (ETDEWEB)

In this work, ZnO thin films have been grown on glass substrates by using a solution of propanol (C{sub 3}H{sub 8}O), water (H{sub 2}O) and zinc acetate (Z{sub n}(CH{sub 3}CO{sub 2}){sub 2}) in acidified medium (pH 5). The obtained films were n doped with ytterbium (Yb) at the rates of 100, 200 and 300 ppm. The structural features of the doped films were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. XRD analysis shows a strong (0 0 2) X-ray diffraction line for increasing Yb-doping amounts. This c-axis preferential orientation of ZnO crystallites is naturally required to use this oxide as transparent conductor in optoelectronic applications. Atomic force microscopy (AFM) analysis shows an enhancement in the surface roughness of the doped ZnO:Yb thin films. Optical measurements were performed in 300-1800 nm domain via transmittance T(lambda) and reflectance R(lambda) spectra. Conjoint optical and thermal properties were ...

2009-10-19

236

Study of ytterbium doping effects on structural, mechanical and opto-thermal properties of sprayed ZnO thin films using the Boubaker Polynomials Expansion Scheme (BPES)  

International Nuclear Information System (INIS)

In this work, ZnO thin films have been grown on glass substrates by using a solution of propanol (C3H8O), water (H2O) and zinc acetate (Zn(CH3CO2)2) in acidified medium (pH 5). The obtained films were n doped with ytterbium (Yb) at the rates of 100, 200 and 300 ppm. The structural features of the doped films were investigated using XRD, atomic force microscopy and scanning electronic microscopy techniques. XRD analysis shows a strong (0 0 2) X-ray diffraction line for increasing Yb-doping amounts. This c-axis preferential orientation of ZnO crystallites is naturally required to use this oxide as transparent conductor in optoelectronic applications. Atomic force microscopy (AFM) analysis shows an enhancement in the surface roughness of the doped ZnO:Yb thin films. Optical measurements were performed in 300-1800 nm domain via transmittance T(?) and reflectance R(?) spectra. Conjoint optical and thermal properties were deduced from the optical measurements in ...

2009-10-19

237

Structural and optical investigations of sodium europium carbonate Na{sub 3}Eu(CO{sub 3}){sub 3}  

Energy Technology Data Exchange (ETDEWEB)

The crystal structure and the luminescence properties of a new carbonate, Na{sub 3}Eu(CO{sub 3}){sub 3}, are presented. Na{sub 3}Eu(CO{sub 3}){sub 3} is orthorhombic, acentric, Ama2, Z = 4; a = 9.942(2) {angstrom}, b = 11.024(3) {angstrom}, c = 7.147(2) {angstrom}; R = 0.019, R{sub w} = 0.051, 2374 unique reflections. The anionic subnetwork is built up from the stacking of {open_quotes}standing on edge{close_quotes} and {open_quotes}flat lying{close_quotes} carbonate layers into which Na{sup +} and Eu{sup 3+} ions are inserted. The symmetry of the EuO{sub 9} polyhedra is C{sub s}. The Eu{sup 3+} ions are inserted. The symmetry of the EuO{sub 9} polyhedra is C{sub s}. The Eu{sup 3+} luminescence technique confirms the presence of a unique low symmetry site for the rare earth atom. The electrostatic crystal field (cf) effects on the {sup 7}F multiplet are evaluated on the basis of the phenomenological cf theory. The simulation using C{sub 2v} symmetry for the rare earth atom gives good ...

1997-08-01

238

Stoichiometry of photorespiration during C3-photosynthesis is not fixed: evidence from combined physical and stereochemical methods  

Energy Technology Data Exchange (ETDEWEB)

The stoichiometry of photorespiration, S, is defined as the fraction of glycolate carbon photorespired. It is postulated that under steady-state conditions there are two determinants of the ratio of photorespiration to net photosynthesis: the partitioning of ribulose bisphosphate between oxidation and carboxylation, and the partitioning of glycolate between reactions leading to complete oxidation to CO/sub 2/ (S . 100%) and those yielding CO/sub 2/ plus serine (S . 25%). S may be calculated using two independent probes of the system. The physical probe, using an infrared gas analyzer, measured photorespiration and net photosynthesis, and hence their ratio PR/NPS . pn(phys). The metabolic probe employed tracer (3R)-D-(3-/sup 3/H1,3-/sup 14/C)glyceric acid to determine r, the fraction of /sup 3/H retained in the triose phosphates leaving the chloroplasts. It is deduced from the postulated model that S . pn(phys) . r/(1 - r). Experiments have been performed with ...

1985-03-01

239

State of the Art Laser Induced Breakdown Spectroscopy  

International Nuclear Information System (INIS)

Methods currently being used or developed for the elemental analysis of materials are chemical analysis, non-destructive inspection and calorimetry. The chemical analysis, which removes high-level radioactive elements through chemical treatments and then performs the quantitative analysis using the ICP-MS(Inductively Coupled Plasma - Mass Spectrometer) or the ID-MS(Isotope Dilution Mass Spectrometer), is recognized the most accurate. However, it requires a long, complex pre-treatment process in which a mass spectrometer could be contaminated. To solve this problem, a new method, which can be performed with high-level radioactivity and at high temperature, was desired. Such a method should also have the same accuracy as the chemical analysis, with a less possibility for instruments to be contaminated. In addition, as interests in the environment and the life quality are increased, a detailed analysis on the environmental impacts is also required. Satisfying all of the above-mentioned, ...

240

Some important aspects of fragment angular momentum in medium energy fission of {sup 238}U  

Energy Technology Data Exchange (ETDEWEB)

Independent isomeric yield ratios of {sup 131}Te, {sup 133}Te and {sup 134}I have been determined at five different energies in the range of 25-44 MeV alpha particle induced fission of {sup 238}U using radiochemical and gamma spectrometric techniques. From the independent isomeric yield ratios, fragment angular momenta (J{sub rms}) have been deduced using a statistical model analysis. The J{sub rms} were also calculated theoretically based on thermal equilibration of various collective modes after considering the occurrence of multichance fission. These data and the literature data for various fragments in the mass region 126-136 in {sup 238}U ({alpha},f), {sup 238}U (p,f) and {sup 238}U ({gamma},f) show the following important features: (i) Both the entrance channel excitation energy and input angular momentum affect the fragment angular momentum in the exit channel. (ii) There are two groups of fission products from the point of view of change of fragment angular ...

1999-03-15

241

Simplified methods in the estimation of the K-value of insulated cargo holds on ships  

Energy Technology Data Exchange (ETDEWEB)

The problem of buried steelwork in cargo hold insulation has been investigated by several using empirical methods. These efforts have resulted in correction factors that serve as a useful aid in the complex task of estimating the K-value of a ship`s cargo holds for the correct dimensioning of the refrigeration plant. Today, the advent of the digital computer has established numerical methods of analysis as a common working tool among practicing engineers. For estimating the flow in cases of buried steelwork that cannot be handled by correction factors, this is an effective approach. This study is an analytical/numerical investigation of the effect that buried steelworks have on the heat leakage across cargo hold walls. It aims at providing enlightenment on the physical significance of the parameters influencing the problem and developing practically simple methods for predicting the heat leakage across the hold walls. The study is set in the steady temperature in a rectangular layer of ...

1992-03-01

242

Sequences, geographic variations and molecular phylogeny of venom phospholipases and threefinger toxins of eastern India Bungarus fasciatus and kinetic analyses of its Pro31 phospholipases A2.  

Science.gov (United States)

Eight phospholipases A2 (PLAs) and four three-finger-toxins (3FTx) from the pooled venom of Bungarus fasciatus (Bf) were previously studied and sequenced, but their expression pattern in individual Bf venom and possible geographic variations remained to be investigated. We herein analyze the individual venom of two Bf specimens from Kolkata (designated as KBf) to address this question. Seven PLAs and five 3FTx were purified from the KBf venoms, and respective cDNAs were cloned from venom glands of one of the snakes. Comparison of their mass and N-terminal sequence revealed that all the PLAs were conserved in both KBf venoms, but that two of their 3FTx isoforms were variable. When comparing the sequences of these KBf-PLAs with those published, only one was found to be identical to that of Bf Vb-2, and the other five were 94-98% identical to those of Bf II, III, Va, VI and XI-2, respectively. Notably, the most abundant PLA isoforms of Bf and KBf venoms contain Pro31 substitution. They ...

2006-12-08

243

Role of nuclear structure on the tilting mode  

Energy Technology Data Exchange (ETDEWEB)

The high spin fraction (HSF) of {sup 131}Te as a function of fragment emission angle has been determined in the 40 MeV alpha-particle induced fission of {sup 238}U using off-line gamma ray spectrometric technique. From the HSF the fragment average spin (J{sub av}) of fission product has been deduced using statistical model analysis. The J{sub av} value of {sup 131}Te is seen to remain nearly constant (10{Dirac_h}) from 90 deg. to 20 deg. On the other hand, the J{sub av} value of {sup 132}I from earlier work shows a drastic decrease (33%) from 11.4{Dirac_h} at 90 deg. to 7.6{Dirac_h} at 20 deg. . However, the yield weighted J{sub av} value of both the products show a decrease of 13%, which in close agreement with the value of 5-10% change from 90 deg. to 0 deg. in the results obtained from gamma ray multiplicity measurements. Thus the drastic difference in the change of fragment average spin (J{sub av}) of individual product from 90 deg. to 20 deg. obtained from the ...

2003-12-11

244

Pteromalus puparum venom impairs host cellular immune responses by decreasing expression of its scavenger receptor gene.  

Science.gov (United States)

Insect host/parasitoid interactions are co-evolved systems in which host defenses are balanced by parasitoid mechanisms to disable or hide from host immune effectors. Although there is a rich literature on these systems, parasitoid immune-disabling mechanisms have not been fully elucidated. Here we report on a newly discovered immune-disabling mechanism in the Pieris rapae/Pteromalus puparum host/parasitoid system. Because venom injections and parasitization suppresses host phagocytosis, we turned attention to the P. rapae scavenger receptor (Pr-SR), posing the hypothesis that P. puparum venom suppresses expression of the host Pr-SR gene. To test our hypothesis, we cloned a full-length cDNA of the Pr-SR. Multiple sequences alignment showed the deduced amino acid sequence of Pr-SR is similar to scavenger receptors of other lepidopterans. Bacterial and bead injections induced Pr-SR mRNA and protein expression, which peaked at 4h post-bead injection. Venom injection ...

2011-07-22

245

Petrographically deduced triassic climate for the Deep River Basin, eastern piedmont of North Carolina  

Energy Technology Data Exchange (ETDEWEB)

A petrographic comparison of Triassic, fluvial sandstones from the Deep River Basin in the eastern piedmont of North Carolina with nearby Holocene stream sands (1) indicates that he Triassic climate was more arid than today's and (2) distinguishes an eastern, more plutonic terrane from a western, more metamorphic source terrane. The paleoclimatic interpretation is based on differences in framework composition between modern and ancient sands of the same grain size, derived from the same rock type, transported similar distances and deposited in similar settings. The Triassic sandstones contain more lithic-fragments but less quartz than otherwise equivalent, modern sand in the Deep River Basin. Feldspar content is more complex, controlled by both source-rock composition and climate. Sand from the more plutonic terrane contains more feldspar and plutonic lithic-fragments than sand from the more metamorphic terrane, which contains more quartz and metamorphic lithic-fragments. This ...

1985-01-01

246

On the Utility of Antiprotons as Drivers for Inertial Confinement Fusion  

Energy Technology Data Exchange (ETDEWEB)

By contrast to the large mass, complexity and recirculating power of conventional drivers for inertial confinement fusion (ICF), antiproton annihilation offers a specific energy of 90MJ/{micro}g and thus a unique form of energy packaging and delivery. In principle, antiproton drivers could provide a profound reduction in system mass for advanced space propulsion by ICF. We examine the physics underlying the use of antiprotons ({bar p}) to drive various classes of high-yield ICF targets by the methods of volumetric ignition, hotspot ignition and fast ignition. The useable fraction of annihilation deposition energy is determined for both {bar p}-driven ablative compression and {bar p}-driven fast ignition, in association with 0-D and 1-D target burn models. Thereby, we deduce scaling laws for the number of injected antiprotons required per capsule, together with timing and focal spot requirements. The kinetic energy of the injected antiproton beam required to ...

2003-10-20

247

Observation and simulation of the energy levels of the trivalent thulium ion in gadolinium oxychloride  

International Nuclear Information System (INIS)

The optical absorption of the Tm"3"+ ion in the gadolinium oxychloride (GdOCl) matrix in the UV, visible, and NIR range was studied at temperatures between 9 and 300 K. The visible luminescence of GdOCl:Tm"3"+ under Ar"+ ion laser and mercury lamp excitation was recorded at 9, 77, and 300 K, too. The crystal field (CF) splitting of the "3H_4_-_6, "3F_2_-_4, "1G_4, "1D_2, and "1I_6 levels of the Tm"3"+ ion deduced from the spectra was analysed according to the C_4_v point symmetry of the RE"3"+ site. The resulting energy level scheme, consisting of 39 levels (i.e. 55 Stark components) out of the total of 70 (91) for the whole 4f"1"2 configuration, was simulated with the aid of a phenomenological theory taking simultaneously into account both the free-ion and CF effects. The model included 13 adjustable parameters describing the electrostatic (the Racah parameters E_0_-_3) and the configuration interaction (the Trees parameters #alpha#, #beta#, and #gamma#) as well ...

1995-06-26

248

Natural ventilation of a room through a large external opening: calculation using a CFD code; Ventilation naturelle d`un local par une grande ouverture exterieure: calcul a l`aide d`un code de champ  

Energy Technology Data Exchange (ETDEWEB)

This paper is dedicated to the numerical study of natural ventilation in a room through a large external opening using the CFD code Fluent. Bidimensional numerical simulations are performed for wind speeds up to 5.55 m-s{sup -1} (20 km-h{sup -1}). We propose a two-step solution procedure with grid refinement. When combined with appropriate thermal boundary conditions, this technique appears very efficient at limiting local convergence problems. Through an analysis of the flow pattern in the cavity, we qualitatively explain those results and define a critical Archimedes number. Calculated air change rates are compared to values deduced from empirical correlations of the literature. Agreement is in general poor, which can be explained by the differences between the conditions of our simulations and those of the experiments that lead to those correlations. However, from our simulations, we derived very clear correlations between the air change coefficient and the ...

1998-02-01

249

Morphological survey of bar, lens, and ring components in galaxies: Secular evolution in galaxy structure  

International Nuclear Information System (INIS)

A morphological survey of barred galaxies is made to investigate the frequency of occurrence, nature, and size distributions of bars, lenses, inner and outer rings, and global spiral structure. The 121 brightest available barred galaxies are examined on Sky Survey copy plates, and on deeper and larger-scale plates, with the following main results.1. Lenses and inner rings are components of major importance in barred galaxies, occurring, respectively, in 54% of SBO--SBa, and 76% of SBab--SBc galaxies. Few early-type galaxies have rings; almost no late-type ones have lenses.2. There is an intimate connection between bars and lenses: in 17 of 20 galaxies with both components, the bar exactly fills the lens in one dimension.3. We suggest that lenses originate as bars, through an unknown process which makes some bars evolve away to a nearly axisymmetric state. Several properties of the proposed process are deduced. We emphasize the possible importance of internal ...

250

Measurement of the {beta}-{nu} angular correlation parameter in the decay of {sup 6}He using a Paul trap; Mesure du coefficient de correlation angulaire {beta}-{nu} dans la decroissance de {sup 6}He a l'aide d'un piege de Paul  

Energy Technology Data Exchange (ETDEWEB)

The central topic of this work is the study of the properties and the implementation of a Paul trap used for the measurement of the beta-neutrino angular correlation parameter in the decay of {sup 6}He. This coefficient provides a signature of the nature of the interactions involved in the weak interaction. The value of this coefficient can be deduced from the kinematical distribution of the decay events. An electromagnetic trap is used for the trapping of {sup 6}He{sup +} ions in a small volume. This trap has an open geometry that enables the detection in coincidence of the electron and the recoil ion emitted in the beta decay. A dedicated detection set up is used for the measurement of the electron energy, the ion time of flight and the position of the two particles for each event. A general description of the LPCTrap facility and of its performances is presented and shows that this set up is able to fulfill the proposed measurement. Especially, a comparison is ...

2007-07-15

251

Magnetic excitations in R_2PdSi_3 studied by inelastic neutron scattering  

International Nuclear Information System (INIS)

R_2PdSi_3 compounds have been found to exhibit rich magnetic phenomena arising from the interplay between RKKY interaction, crystal electric field effects and geometric frustration due to the derived hexagonal AlB_2 structure. The observed crystallographic superstructure further complicates the CEF level scheme. Inelastic neutron scattering measurements on single crystals of Tm_2PdSi_3 and Er_2PdSi_3 have been performed at the cold triple axis spectrometer PANDA in FRM-II. Both compounds order antiferromagnetically at T_N=7 K and 2.1 K respectively; Er_2PdSi_3 undergoes a second phase transition at T_2=2 K. Several low lying CEF excitations (below 10 meV) were observed. The intensity of the lowest excitation show strong directional dependence (in HK0 plane for Er_2PdSi_3 and in HHL plane for Tm_2PdSi_3), from which the details of the transitional matrix could be deduced. Measurements in magnetic fields up to 13 T show Zeeman splitting of the CEF excitations. In ...

2009-03-22

252

Interpretation of quasi-Fermi level splitting in Cu(Ga,In)Se2-absorbers by confocally recorded spectral luminescence and numerical modeling  

International Nuclear Information System (INIS)

Spectral room temperature photoluminescence (pl) of polycrystalline Cu(In,Ga)Se2 films (CIGSe) is evaluated with respect to optoelectronic properties and in particular for the determination of the splitting of quasi-Fermi levels (EFn - EFp). For lateral resolution of ? 1 ?m a confocal pl-setup is used. The depth profile of the excess carrier densities determining the rates of radiative transitions strongly govern the spectral pl-shape which has been numerically modeled with a matrix transfer formalism. In this optical approach we discriminate for wave propagation and attenuation in a multilayer system between a plane-wave ansatz and a 3D-spherical formalism, depending on excitation area large or small/similar compared to the thickness of the absorber. In both cases re-absorption of photons in energetic regimes with absorption approaches unity, from which the splitting of the quasi-Fermi levels is preferentially deduced, substantially influence the spectral ...

2009-02-02

253

Heavy chain of Acanthamoeba myosine IB is a fusion of myosin-like and non-myosin-like sequences  

Energy Technology Data Exchange (ETDEWEB)

Acanthamoeba castellanii myosins IA and IB demonstrate the catalytic properties of a myosin and can support analogues of contractile and motile activity in vitro, but their single, low molecular weight heavy chains, roughly globular shapes, and inabilities to self-assemble into filaments make them structurally atypical myosins. The authors present the complete amino acid sequence of the 128-kDa myosin IB heavy chain, which they deduced from the nucleotide sequence of the gene and which reveals that the polypeptide is a fusion of myosin-like and non-myosin-like sequences. Specifically, the amino-terminal approx. 76 kDa of amino acid sequence is highly similar to the globular head sequences of conventional myosins. By contrast, the remaining approx. 51 kDa of sequence shows no similarity to any portion of conventional myosin sequences, contains regions that are rich in glycine, proline, and alanine residues, and lacks the distinctive sequence characteristics of an ...

1987-10-01

254

Heavy chain of Acanthamoeba myosine IB is a fusion of myosin-like and non-myosin-like sequences  

International Nuclear Information System (INIS)

Acanthamoeba castellanii myosins IA and IB demonstrate the catalytic properties of a myosin and can support analogues of contractile and motile activity in vitro, but their single, low molecular weight heavy chains, roughly globular shapes, and inabilities to self-assemble into filaments make them structurally atypical myosins. The authors present the complete amino acid sequence of the 128-kDa myosin IB heavy chain, which they deduced from the nucleotide sequence of the gene and which reveals that the polypeptide is a fusion of myosin-like and non-myosin-like sequences. Specifically, the amino-terminal #approx# 76 kDa of amino acid sequence is highly similar to the globular head sequences of conventional myosins. By contrast, the remaining #approx# 51 kDa of sequence shows no similarity to any portion of conventional myosin sequences, contains regions that are rich in glycine, proline, and alanine residues, and lacks the distinctive sequence characteristics of an ...

255

Electromagnetic interactions in the {Delta}-resonance region  

Energy Technology Data Exchange (ETDEWEB)

Cross sections for some electro- and photoinduced spallation reactions on {sup 27}Al and {sup 51}V are measured in the energy region 130 MeV to 580 MeV with the activation method. Comparisons are made with calculations based on the Dalitz formalism for virtual photon spectra, and Monte Carlo calculations based on a cascade evaporation model, respectively. By use of Bremsstrahlung with end-point energies from threshold to 750 MeV, the yields for photo- production of{pi}{sup -}leading to ground and isomeric states in {sup 197}Hg are measured with the activation method. The activity from the Hg-isotopes were measured after a chemical separation of Hg from the target material. The yields and isomeric ratios are compared with impulse approximation calculations. For the photoproduction of {sup 195m}Hg and {sup 192}Hg from {sup 197}Au, the yields were measured. The experimental mean cross sections are compared with data from other experiments and with cascade evaporation calculations. Cross ...

1995-03-01

256

Development of an inactive heat removal system for high temperature reactors  

International Nuclear Information System (INIS)

Growing public and political interests towards incorporating passive safety features in nuclear installations, let Siempelkamp in late 1987 propose a solution consisting of a prestressed cast-iron pressure vessel and a passive heat removal system, integrated in the reactor cell surrounding the vessel. This solution combines the inherent safety of a prestressed metallic pressure vessel with the advantages of a passive heat removal system and thus constitutes a major step towards the goal of further reducing potential residual risks. The design had to meet the boundary conditions for reactor core and reactor building of the modular 200 MWth pebble bed reactor of Siemens/-KWU. The engineering design showed that many input parameters needed for the finite-element-analysis of the overall structure required a verification by measurements in a well scaled test setup. This was especially required for the heat transfer from the liner of the prestressed cast-iron pressure vessel to the natural ...

1994-08-01

257

Crystal structure of ABPO{sub 5} and optical study of Pr{sup 3+} embedded in these compounds  

Energy Technology Data Exchange (ETDEWEB)

The crystal structure of borophosphates ABPO{sub 5} (A = alkaline earth or Pb) was resolved on a polycrystalline sample using the Rietveld method. The x-ray diffraction patterns data show that ABPO{sub 5} crystallize in a centrosymmetric space group P3{sub 1}21 and their structure is related to the borogermanates REBGeO{sub 5} with a stillwellite-type structure. Pr{sup 3+} ion was used as a local structural probe to corroborate the structural resolution results. Absorption and fluorescence spectra of A{sub 1-x}Pr{sub x}BP{sub 1-x}Ge{sub x}O{sub 5} (A alkaline earth or Pb; x = 0.05) have been investigated at different temperatures. At 9 K the 3{sup H}{sub 4}{yields}{sup 3}P{sub 0} transition of trivalent praseodymium ion (4f{sup 2} configuration) is observed as a single line. This indicates a unique crystallographic site for the rare earth ion in these compounds replacing the divalent cation. Energy level schemes were deduced from the low-temperature spectroscopic ...

2001-10-22

258

Crystal structure of ABPO_5 and optical study of Pr"3"+ embedded in these compounds  

International Nuclear Information System (INIS)

The crystal structure of borophosphates ABPO_5 (A = alkaline earth or Pb) was resolved on a polycrystalline sample using the Rietveld method. The x-ray diffraction patterns data show that ABPO_5 crystallize in a centrosymmetric space group P3_121 and their structure is related to the borogermanates REBGeO_5 with a stillwellite-type structure. Pr"3"+ ion was used as a local structural probe to corroborate the structural resolution results. Absorption and fluorescence spectra of A_1_-_xPr_xBP_1_-_xGe_xO_5 (A alkaline earth or Pb; x = 0.05) have been investigated at different temperatures. At 9 K the 3"H_4#->#"3P_0 transition of trivalent praseodymium ion (4f"2 configuration) is observed as a single line. This indicates a unique crystallographic site for the rare earth ion in these compounds replacing the divalent cation. Energy level schemes were deduced from the low-temperature spectroscopic measurements. Comparing the electronic level splittings of studied ...

2001-10-22

259

Committed T lymphocyte stem cells of rats. Characterization by surface W3/13 antigen and radiosensitivity  

Energy Technology Data Exchange (ETDEWEB)

The existence of stem cells committed to the T lymphoid lineage was deduced from studying how rat T and B stem cells differ in their expression of membrane W3/13 antigen and in their susceptibility in vivo to gamma irradiation. Stem cell activity of rat bone marrow and fetal liver was measured in long-term radiation chimeras using B and T cell alloantigenic surface markers to identify the progeny of donor cells. Monoclonal mouse anti-rat thymocyte antibody W3/13 labeled approximately 40% of fetal liver cells and 60-70% of young rat bone marrow cells (40% brightly, 25% dimly). Bright, dim, and negative cells were separated on a fluorescence-activated cell sorter. All B and T lymphoid stem cells in fetal liver were W3/13 bright, as were B lymphoid stem cells in bone marrow. W3/13 dim bone marrow had over half the T cell repopulating activity of unseparated marrow but gave virtually no B cell repopulation. In further experiments, the radiosensitivity of endogenous B ...

1981-01-01

260

Calculation of the cyclic fatigue strength of notched and multiaxially loaded specimens of the bainitic steel 100Cr6; Berechnung der Wechselfestigkeit von gekerbten und mehrachsig beanspruchten Proben des Stahls 100Cr6 im bainitischen Zustand  

Energy Technology Data Exchange (ETDEWEB)

High-strength, fully hardening steels are used in general for applications involving severe wear and frequently also additional cyclic stress. For the latter condition, the available information and experimental data for component dimensioning are insufficient. Work reported in the dissertation therefore was intended to establish experimental information showing the performance of the bainitic roller bearing steel 100Cr6 and deducing rules of applicability to components, of the fatigue strength data obtained with the specimens. Various models for calculating the fatigue strength are presented together with their application to the steel 100Cr6. The results show that the weakest link model is a good concept for fatigue strength calculation, taking into account multiaxial loading. (orig/CB) [Deutsch] Hochfeste durchhaertende Staehle unterliegen in der Regel hohen Verschleissbeanspruchungen und werden darueber hinaus oftmals zusaetzlich schwingend beansprucht. Fuer ...

1998-12-01

261

APERTURE SYNTHESIS IMAGING OF V892 Tau AND PV Cep: DISK EVOLUTION  

International Nuclear Information System (INIS)

I present a study of two Herbig Ae stars that are in completely different evolutionary stages: V892 Tau and PV Cep. Using sub-arcsecond interferometric observations obtained with the Combined Array for Research in Millimeter-wave Astronomy at #lambda# = 1.3 and 2.7 mm, I have for the first time resolved their disks. I deduce that the 5 Myr old V892 Tau has a low dust opacity index #beta# = 1.1 and a disk mass of #approx#0.03 M_s_u_n. These values correspond to the growth of its dust into large, up to centimeters size, structures. In contrast, the very young (a few x10"5 yr) PV Cep has a quite high opacity index #beta# = 1.75 and a more massive disk 0.8 M_s_u_n. PV Cep has the youngest resolved disk around any Herbig Ae star. Unlike the youngest T Tauri and Class 0 stars, which contain large and processed grains, the young Herbig Ae star, PV Cep, disk contains interstellar-medium-like unprocessed dust. This suggests that PV Cep's dust evolution is slower than T ...

2010-10-10

262

A study of Pd-Ta on Si(100) using AES, RBS and variable energy positron annihilation  

Science.gov (United States)

The applicability of Pd/sub x/Ta/sub 1-x/ as a diffusion barrier on Si has been investigated. For this purpose Pd/sub x/Ta/sub 1-x/ films of 200 nm thickness (x ranges from 0 to 1) were deposited on Si(100), and the reaction between over-layer and substrate was studied as a function of temperature. Interaction was found to occur at temperatures increasing with the Ta content. The as-deposited Pd/sub x/Ta/sub 1-x/ films with 0.2 less than or equal to x less than or equal to 0.6 were found to be amorphous. The amorphous phase had a higher reaction temperature than the crystalline one, causing a discontinuous step in the reaction temperature. RBS spectra revealed that for the Pd-rich compositions first a stoichiometric Pd2Si layer formed underneath a pure Ta layer. At higher temperatures TaSi2 formed at the surface. For Ta-rich compositions Pd2Si formed first as well, however, the reaction temperature was so high that Pd2Si grains formed in a Si matrix. The defect density of the Ta layer, ...

1988-01-01

263

Vitamin C and a-naphthoflavone prevent estrogen-induced mammary tumors and decrease oxidative stress in female ACI rats  

British Library Electronic Table of Contents (United Kingdom)

The mechanisms underlying the pathogenesis of estrogen-induced breast carcinogenesis remain unclear. The present study investigated the roles of estrogen metabolism and oxidative stress in estrogen-mediated mammary carcinogenesis in vivo. Female August Copenhagen Irish (ACI) rats were treated with 17b-estradiol (E2), the antioxidant vitamin C, the estrogen metabolic inhibitor a-naphthoflavone (ANF), or cotreated with E2 + vitamin C or E2 + ANF for up to 8 months. E2 (3 mg) was administered as an subcutaneous implant, ANF was given via diet (0.2%) and vitamin C (1%) was added to drinking water. At necropsy, breast tumor incidence in the E2, E2 + vitamin C and E2 + ANF groups was 82, 29 and 0%, respectively. Vitamin C and ANF attenuated E2-induced alterations in oxidative stress markers in b...

2009-01-01

264

The origin of natural gas and the hydrocarbon charging history of the Yulin gas field in the Ordos Basin, China  

British Library Electronic Table of Contents (United Kingdom)

The genetic type, source and charging history of natural gas in the Yulin gas field in the Ordos Basin have been studied by combining the carbon isotopic composition of natural gas and geochemical characteristics of light hydrocarbons with carbon isotope fractionation model results and fluid inclusion analysis. The carbon isotopic composition of methane and ethane in the Yulin gas field is relatively enriched in ^1^3C with d^1^3C1 values ranging from -35.3%% to -29.8%% (average value=-32.4%%) and d^1^3C2 ranging from -26.3%% to -23.5%% (average value=-24.8%%). The C7 light hydrocarbons are predominated by methylcyclohexane, accounting for 65.8% to 80.9% (average value=71.6%), which is characteristic of coal-derived gas. Furthermore, the gas geochemistry indicates that, although marine lime...

2010-01-01

265

Synthesis, characterization and evaluation of antibacterial activity of some thiazolo[3,2-b][1,2,4]triazole incorporating diphenylsulfone moieties  

British Library Electronic Table of Contents (United Kingdom)

A series of thiazolo[3,2-b][1,2,4]triazole incorporating diphenylsulfone moieties were synthesized starting from 5-[4-(4-X-phenylsulfonyl)phenyl]-4H-1,2,4-triazole-3-thioles 3a-c, X=H, Cl, Br. Thus, alkylation of 1,2,4-triazoles 3 with phenacyl bromide or 4-bromophenacyl bromide afforded S-substituted 1,2,4-triazoles 4, 5. These new intermediates 4 and 5, in the presence of H2SO4 (c), were cyclized to 2-[4-(4-X-phenylsulfonyl)phenyl]-6-(4-Y-phenyl)[1,3]thiazolo[3,2-b]-[1, 2,4]-triazoles 6, 7 (I) and not to isomeric thiazolo[2,3-c][1,2,4]-triazoles 6, 7 (II). The newly synthesized compounds were characterized by IR, 1H, 13C NMR and elemental analysis. MS spectra confirmed the formation of thiazolo[3,2-b][1,2,4]triazole 6, 7 (forms I) in detriment of [2,3-c] isomeric compounds (forms II). Th...

2009-01-01

266

Spark plasma sintered tantalum carbide: Effect of pressure and nano-boron carbide addition on microstructure and mechanical properties  

British Library Electronic Table of Contents (United Kingdom)

TaC and TaC-1wt.% B4C powders were consolidated using spark plasma sintering (SPS) at 1850^oC and varying pressure of 100, 255 and 363MPa. The effect of pressure on the densification and grain size is evaluated. The role of nano-sized B4C as sintering aid and grain growth inhibitor is studied by means of XRD, SEM and high resolution TEM. Fully dense TaC samples were produced at a pressure of 255MPa and higher at 1850^oC. The increasing pressure also resulted in an increase in TaC grain size. Addition of B4C leads to an increase in the density of 100MPa sample from 89% to 97%. B4C nano-powder resists grain growth even at high pressure of 363MPa. The formation of TaB2/Carbon at TaC grain boundaries helps in pinning the grain boundary and inhibiting grain growth. The effect of B4C addition on...

2011-01-01

267

Proton spin lattice relaxation studies in lithium ammonium sulfate LiNH_4SO_4  

International Nuclear Information System (INIS)

Lithium ammonium sulfate (LAS) undergoes a phase transition at Tsub(c1) = 459.5deg K from a paraelectric phase (phase 1) to a ferroelectric phase (phase II) and again at Tsub(c2) = 283deg K to a polar ferroelastic phase (phase III). Proton spin lattice relaxation investigations in the temperature range 480-77deg K at 10 MHz show discontinuous changes in Tsub(1) at the transition temperatures, indicating first order phase transitions. The absence of the slow motion region (#omega#sub(not)tausub(not)>>1) shows that the ammonium ions are reorienting fast enough to keep the resonance absorption line narrow down to liquid nitrogen temperatures. The possibility of a second minimum and a low activation energy, Esub(a) = 2.659 kcal/mole, in phase III suggest the possibility of tunnelling of the protons at low temperatures. The nature of the transitions have been discussed in the light of the available literature. The unusually high activation ...

1978-12-31

268

Potassium deposition on a thiophene-terminated alkanethiol monolayer  

International Nuclear Information System (INIS)

Potassium deposition in ultrahigh vacuum on 12-(3-thienyl)dodecanethiol monolayers assembled on gold surfaces has been investigated using X-ray and ultraviolet photoelectron spectroscopies (XPS and UPS). Angle-resolved XPS indicates that initially deposited potassium penetrates the self-assembled monolayer (SAM) and diffuses to the SAM/Au interface. Even after large metal doses, the presence of thiophene ring valence electronic states in the UPS spectra confirms that most of the thiophene rings (at the SAM/vacuum interface) are not covered by potassium. The binding energy shifts of the thiophene ring valence states and the C1s and thiophene S2p peaks, referenced to the Fermi level, are due to the work function changes of the gold substrate. This indicates that these electronic states are pinned to the vacuum level, in contrast to the thiolate S2p orbital, which is pinned to the Fermi level. For large potassium doses, the appearance of new ...

2009-05-01

269

Performance of a modified two-dimensional gamma scan system in spent fuel pin studies  

International Nuclear Information System (INIS)

This work assesses the performance of a modified two-dimensional gamma scan system in spent fuel pin studies. The techniques for a two-dimensional gamma scan studied have been developed at the Hot Cell of Institute of Nuclear Energy Research (INER). Samples are acquired from the spent fuel pin, TPC-SP-C1, which was irradiated in a commercial reactor core (the first of its kind in Taiwan) for 2 years and then deposited in a cooling pool for 10 years. The spent fuel pin was then transferred into INER for further examination. The gamma scanning system was driven by a step motor which had an accuracy within 0.1 mm in both X-Y directions. Data obtained from this system are presented in both an isotopic distribution and contour plot. Results in this study closely correspond to those in other investigations, thereby confirming the effectiveness of this modified system. (author)

1999-11-01

270

Measurement of the dipion mass spectrum in X(3872) ---> J/psi pi+ pi- decays  

Energy Technology Data Exchange (ETDEWEB)

The authors measure the dipion mass spectrum in X(3872) {yields} J/{psi}{pi}{sup +}{pi}{sup -} decays using 360 pb{sup -1} of {bar p}p collisions at {radical}s = 1.96 TeV collected with the CDF II detector. The spectrum is fit with predictions for odd C-parity ({sup 3}S{sub 1}, {sup 1}P{sub 1}, and {sup 3}D{sub J}) charmonia decaying to J/{psi}{pi}{sup +}{pi}{sup -}, as well as event C-parity states in which the pions are from {rho}{sup 0} decay. The latter case also encompasses exotic interpretations, such as a D{sup 0}{bar D}*{sup 0} molecule. Only the {sup 3}S{sub 1} and J/{psi} {rho} hypotheses are compatible with the data. Since {sup 3}S{sub 1} is untenable on other grounds, decay via J/{psi} {rho} is favored, which implies C = +1 for the X(3872). Models for different J/{psi}-{rho} angular momenta L are considered. Flexibility in the models, especially the introduction of {rho}-{omega} interference, enable good descriptions of the data for ...

2005-12-01

271

Influence of long-time stress relief treatments on the dynamic fracture toughness properties of ASME SA508 C1 2a and ASME SA533 GR B C12 pressure vessel steels  

Energy Technology Data Exchange (ETDEWEB)

Dynamic fracture toughness tests were performed on materials which had been subjected to one of three long-time post weld type stress relief heat treatments: 48 hours at 1000/degree/F (538/degree/C), 24 hours at 1125/degree/F (607/degree/C), and 48 hours at 1125/degree/F (607/degree/C). Linear elastic K/sub Id/ results were obtained at low temperatures while J-integral techniques were utilized to evaluate dynamic fracture toughness over the transition and upper shelf temperature ranges. Tensile, Charpy impact, and drop weight nil-ductility transition tests as well as room temperature, air environment fatigue crack growth rate tests (SA508 Cl 2a only) were also performed. The fracture toughness of both materials exceeded the ASME specified minimum reference toughness K/sub IR/ curve. 17 refs.

1982-03-01

272

Influence of long-time stress relief treatments on the dynamic fracture toughness properties of ASME SA508 C1 2a and ASME SA533 GR B C12 pressure vessel steels  

International Nuclear Information System (INIS)

Dynamic fracture toughness tests were performed on materials which had been subjected to one of three long-time post weld type stress relief heat treatments: 48 hours at 1000/degree/F (538/degree/C), 24 hours at 1125/degree/F (607/degree/C), and 48 hours at 1125/degree/F (607/degree/C). Linear elastic K/sub Id/ results were obtained at low temperatures while J-integral techniques were utilized to evaluate dynamic fracture toughness over the transition and upper shelf temperature ranges. Tensile, Charpy impact, and drop weight nil-ductility transition tests as well as room temperature, air environment fatigue crack growth rate tests (SA508 Cl 2a only) were also performed. The fracture toughness of both materials exceeded the ASME specified minimum reference toughness K/sub IR/ curve. 17 refs.

273

Fifteenmile Basin habitat enhancement project : annual report FY 1990.; ANNUAL  

International Nuclear Information System (INIS)

The goal of the Fifteenmile Creek Habitat Improvement project is to improve wild winter steelhead habitat in the Fifteenmile Creek Basin. This goal was addressed under the Columbia River Basin Fish and Wildlife Program, Measure 703 (c) (1) - Action Item 4.2. Construction of fish habitat structures was completed on approximately 3.5 miles of Eightmile Creek and on approximately 8.5 miles of Fifteenmile Creek. A total of 15,435 yds of rock was placed to improve rearing and spawning habitat, and to improve water quality and reduce siltation. Riparian protection fencing was completed on 1.8 miles of Dry Creek, approximately 1.75 miles on Eightmile Creek, and 4.75 miles on Fifteenmile Creek. Approximately 10 miles of stream will receive protection from the 8 miles of new fencing installed and 6.5 miles of abandoned fence repaired. Irrigation withdrawal screens were installed at six irrigation pump withdrawals. These screens functioned satisfactorily ...

274

Electrical resistivity and thermal expansion coeffcient of carbon-black-filled compounds around T_g  

International Nuclear Information System (INIS)

A Michelson interferometer and a CCD detector were used to measure the number of interference fringes related to the expansion length of rubber sample. The sample was situated in a microcryostat, and the temperature of the sample was varied from -200 .deg. C to +80 .deg. C. Various types of carbon black filled rubber (Duradene, Sn-SSBR) samples were used to determine the glass transition temperatures (T_g) and the thermal coeffcients (#alpha#). The mixing ratio was 0, 10, 30, 40, 50, or 70 parts per hundred of carbon black to Sn-SSBR rubber. For the unfilled rubber of Sn-SSBR, the T_g was about -24 .deg. C, and the thermal coeffcient was 1.18 X 10"-"4 .deg. C"-"1. The thermal coeffcients sharply increased around T_g for all samples, and decreased with increasing doping ratio of carbonblack from 0 .deg. C to 30 .deg. C. The volume resistivity was measured for natural rubber and EPDM rubber. They had maximum volume resistivities of 1.5 X 10"6 ...

2004-04-01

275

Dissociative decay of n = 3 levels in H/sub 2/. I. Populated in charge exchange of H/sub 2/ /sup +/ with Cs  

Energy Technology Data Exchange (ETDEWEB)

Rotationally resolved spectra of kinetic energy releases epsilon-c in predissociations of H/sub 2/, after dissociative charge exchange of H/sub 2/ /sup +/ with Cs atoms, are obtained. The experiments are performed with natural and with pure parahydrogen. The predissociations with epsilon-c<1.9 eV constitute less than 5% of the total amount of dissociations to HXchemically bondH at a beam energy of 5 keV. All strong rotational peaks observed could be attributed to n = 3 Rydberg states which predissociate to H(1s)+H(2l). Vibrational-rotational series are observed of the d /sup 3/Pi/sub u//sup +/, D /sup 1/Pi/sub u//sup +/, and J /sup 1/..delta../sub g//sup +/ states. Predissociation by barrier tunneling is reported of v = 4 levels of the h /sup 3/..sigma../sub g//sup +/ state and of v = 4 and 5 levels of the i /sup 3/Pi/sub g/ state. Selectivity of the charge-exchange process for different n = 3 states, or even for different parity states, is ...

1986-11-01

276

Culture-area relation in Axelrod's model for culture dissemination  

CERN Document Server

A salient facet of Axelrod's model for culture dissemination or social influence is the existence of many multicultural absorbing states. The dependence of the number $C$ of different, coexisting cultures on the size $A$ of the territory or, equivalently, on the number of agents -- the culture-area relation -- is investigated through extensive simulations. This relation exhibits a strong qualitative dependence on the two parameters of the model, namely, the number $F$ of culture features and the number $q$ of values that each feature can take on. We find that a non-monotonous culture-area relation, for which the number of cultures decreases when the area grows beyond a certain size, occurs for $q$ smaller than a threshold value $q_c = q_c (F)$ provided that $F \\geq 3$. In the limit of infinite area, this threshold value signals the onset of a discontinuous phase transition between a homogeneous regime for which C=1, and a completely disordered ...

2009-01-01

277

Compost amendment of Cu-Zn minespoil reduces toxic bioavailable heavy metal concentrations and promotes establishment and biomass production of Bromus carinatus (Hook and Arn.)  

International Nuclear Information System (INIS)

A series of lab and greenhouse studies were undertaken to understand how Cu and Zn toxicity influences Bromus carinatus (Hook and Arn.) growth, to what degree an organic amendment (yard waste compost) may reduce Cu and Zn bioavailability in Cu-Zn minespoil and promote plant growth in combination with fertilizer, and how the vertical distribution of compost in the minespoil influences rooting depth. Root Cu and Zn toxicity thresholds were determined to be 1 mg L"-"1 and 10 mg L"-"1 in solution, respectively. The compost amendment had exceptionally high Cu and Zn binding capacities (0.17 and 0.08 g metal g C"-"1, for Cu and Zn, respectively) that were attributed to high compost humic and fulvic acid concentrations. Maximum plant biomass was achieved when minespoil was amended with compost and fertilizer in combination. Fertilizer alone had no effect on plant growth. Mixing compost into the minespoil was essential to promote adequate rooting ...

2007-07-01

278

Chemical properties of positive singly charged astatine ion in aqueous solution  

Energy Technology Data Exchange (ETDEWEB)

The mobility of oxidized astatine in solutions H(Na)ClO/sub 4/ (..mu..=0.4M)-1.10/sup -4/M K/sub 2/Cr/sub 2/O/sub 7/ has been measured at 25 degC in the interval 0.63<=pH<=1.68. Under these conditions astatine migrates to the cathode only. The speeds of the migration depends upon the concentration of hydrogen ions in solutions are: pH 1.68 Usub(c)=1.17.10/sup -4/ cm/sup 2/ V/sup -1/ s/sup -1/; pH 0.63 Usub(c)=2.67.10/sup -4/ cm/sup 2/ V/sup -1/ s/sup -1/. The effect agrees with the opinion that the singly charged cation of astatine formed in acidic solutions is a strong aquacomplex ((H/sub 2/O)sub(x)At)/sup +/ (x=1-2) (protonated hypoastatic acid). Deprotonation constant of this cation is Ksub(dp)=0.032+-0.005. Specific properties of the astatine cation are given. They can be explained, probably, through the peculiarities of its structure. 14 refs.

1984-08-01

279

Chemical properties of positive singly charged astatine ion in aqueous solution  

International Nuclear Information System (INIS)

The mobility of oxidized astatine in solutions H(Na)ClO_4 (#mu#=0.4M)-1.10"-"4M K_2Cr_2O_7 has been measured at 25 degC in the interval 0.63<=pH<=1.68. Under these conditions astatine migrates to the cathode only. The speeds of the migration depends upon the concentration of hydrogen ions in solutions are: pH 1.68 Usub(c)=1.17.10"-"4 cm"2 V"-"1 s"-"1; pH 0.63 Usub(c)=2.67.10"-"4 cm"2 V"-"1 s"-"1. The effect agrees with the opinion that the singly charged cation of astatine formed in acidic solutions is a strong aquacomplex [(H_2O)sub(x)At]"+ (x=1-2) (protonated hypoastatic acid). Deprotonation constant of this cation is Ksub(dp)=0.032+-0.005. Specific properties of the astatine cation are given. They can be explained, probably, through the peculiarities of its structure. (author).

280

BWNT assessment of TRAC/PF1-MOD2  

International Nuclear Information System (INIS)

The TRAC/PFI-MOD2 Version 5.3 code was assessed against six FLECHT-SEASET forced reflood tests (31504, 31203, 31302, 31701, 34209, and 31922) and two cylindrical core test facility (CCTF) tests [C1-19 and C2-6]. The objective of this study was to evaluate the clad thermal response predictive capabilities of the code with the newly added reflood model under large-break loss-of-coolant accident (LOCA) conditions in a pressurized water reactor (PWR). The TRAC model for the FLECHT-SEASET test facility was developed from a RELAP5 model. The test section was modeled using a vessel component with 23 axial levels, 1 radial ring, and 1 azimuthal cell. Test inlet and exit conditions were modeled using fill and break components, respectively. The measured lower and upper plenum test conditions were input to the model. The electrically heated rod was modeled using a rod component with 22 axial mesh points. The axial boundary of each mesh point coincided ...

1993-11-14

281

A study on heat-transfer enhancement by a square-rod array in an impinging jet system  

Energy Technology Data Exchange (ETDEWEB)

An impinging jet is a widely used technique for realizing high heat-transfer rates between a fluid and a surface. However, the area of enhanced heat transfer is limited to the neighborhood of the stagnation point. In this study, heat transfer is augmented remote from the stagnation point in an impinging plane jet system by a rod array located near the wall. Each square rod in the array was positioned normal to the flow direction and parallel to the flat plate surface. The distance between the nozzle and the flat plate (H) and the spacing between the rods and the flat plate surface (C) were changed to find the optimum values. The largest heat-transfer augmentation was obtained for C = 1 mm, H/B = 10, where the jet nozzle width is B. In this case, the heat-transfer coefficient averaged over an area 2B from the stagnation point is about 1.6 times greater compared to that without a rod array.

1996-07-01

282

A new fuel cell electrocatalyst based on carbonized polyacrylonitrile foam: The nature of platinum-support interactions  

Energy Technology Data Exchange (ETDEWEB)

X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) have been conducted on a new fuel cell electrocatalytic material based on a highly porous carbonized polyacrylonitrile (PAN) microcellular foam with very low platinum loading ({approximately}13 to 23 {micro}g/cm{sup 2}). TEM images of this material clearly show the existence of nanometer size platinum particles which are homogeneously distributed in the highly porous carbonized PAN matrix. An XPS study of Pt-loaded PAN indicates that C 1s, O 1s, and N 1s peaks shift to lower binding energies, compared to virgin PAN. It was concluded that special metal-support interaction exists, through the formation of a charge-transfer complex between platinum and pyridine-type nitrogen atoms of PAN support. This interaction leads to the enhancement of the catalytic activity, and the improvement of the long-time stability of this electrocatalyst.

1997-01-01

283

A DC-81-indole conjugate agent suppresses melanoma A375 cell migration partially via interrupting VEGF production and stromal cell-derived factor-1a-mediated signaling  

British Library Electronic Table of Contents (United Kingdom)

Pyrrolo[2,1-c][1,4]benzodiazepine (PBD) chemicals are antitumor antibiotics inhibiting nucleic acid synthesis. An indole carboxylate-PBD hybrid with six-carbon spacer structure (IN6CPBD) has been previously demonstrated to induce melanoma cell apoptosis and reduce metastasis in mouse lungs. This study aimed at investigating the efficacy of the other hybrid compound with four-carbon spacer (IN4CPBD) and elucidating its anti-metastatic mechanism. Human melanoma A375 cells with IN4CPBD treatment underwent cytotoxicity and apoptosis-associated assays. Transwell migration assay, Western blotting, and ELISA were used for mechanistic study. IN4CPBD exhibited potent melanoma cytotoxicity through interrupting G1/S cell cycle progression, increasing DNA fragmentation and hypodipoidic DNA contents, a...

2011-01-01

284

THE DOUBLE-DEGENERATE NUCLEUS OF THE PLANETARY NEBULA TS 01: A CLOSE BINARY EVOLUTION SHOWCASE  

International Nuclear Information System (INIS)

We present a detailed investigation of SBS 1150+599A, a close binary star hosted by the planetary nebula PN G135.9+55.9 (TS 01). The nebula, located in the Galactic halo, is the most oxygen-poor known to date and is the only one known to harbor a double degenerate core. We present XMM-Newton observations of this object, which allowed the detection of the previously invisible component of the binary core, whose existence was inferred so far only from radial velocity (RV) and photometric variations. The parameters of the binary system were deduced from a wealth of information via three independent routes using the spectral energy distribution (from the infrared to X-rays), the light and RV curves, and a detailed model atmosphere fitting of the stellar absorption features of the optical/UV component. We find that the cool component must have a mass of 0.54 #+-# 0.2 M_s_u_n, an average effective temperature, T_e_f_f, of 58,000 #+-# 3000 K, a mean radius of 0.43 #+-# ...

2010-05-01

285

Observation and simulation of the energy levels of the trivalent thulium ion in gadolinium oxychloride  

Energy Technology Data Exchange (ETDEWEB)

The optical absorption of the Tm{sup 3+} ion in the gadolinium oxychloride (GdOCl) matrix in the UV, visible, and NIR range was studied at temperatures between 9 and 300 K. The visible luminescence of GdOCl:Tm{sup 3+} under Ar{sup +} ion laser and mercury lamp excitation was recorded at 9, 77, and 300 K, too. The crystal field (CF) splitting of the {sup 3}H{sub 4-6}, {sup 3}F{sub 2-4}, {sup 1}G{sub 4}, {sup 1}D{sub 2}, and {sup 1}I{sub 6} levels of the Tm{sup 3+} ion deduced from the spectra was analysed according to the C{sub 4v} point symmetry of the RE{sup 3+} site. The resulting energy level scheme, consisting of 39 levels (i.e. 55 Stark components) out of the total of 70 (91) for the whole 4f{sup 12} configuration, was simulated with the aid of a phenomenological theory taking simultaneously into account both the free-ion and CF effects. The model included 13 adjustable parameters describing the electrostatic (the Racah parameters E{sub 0-3}) and the ...

1995-06-26

286

Measurement of level lifetimes in the ps range and model interpretations for neutron-rich A {approx_equal} 100 nuclei  

Energy Technology Data Exchange (ETDEWEB)

The nuclear structure of A {proportional_to} 100 nuclei has been studied in the frame of this thesis with a recently developed {beta} - {gamma} - {gamma} triple coincidence fast timing technique and different models such as shell model, hydrodynamic model, Nilsson and particle-rotor models. This technique which allows the measurement of the level lifetimes in the ps range has been applied at JOSEF at the research reactor DIDO of KFA Juelich in studes of the short-lived neutron-rich nuclei in the A {approx_equal} 100 region. Lifetimes of level in {sup 96},{sup 98},{sup 100} ZR, {sup 99},{sup 101}-{sup 104} Nb, {sup 100}-{sup 105} Mo have been measured, which are in many cases completely new, and otherwise more precise than previously published data. From the lifetimes of the members of rotational bands, the size of the nuclear deformations has been deduced. (orig./HSI). [Deutsch] Im Rahmen dieser Doktorarbeit wurde die Kernstruktur der A {proportional_to} 100 Kerne ...

1992-08-01

287

Application of photogrammetry, remote sensing and GIS in the environmental monitoring of the Deutsche Steinkohle AG; Einsatz von Photogrammetrie, Fernerkundung und GIS im Umweltmonitoring der Deutschen Steinkohle AG  

Energy Technology Data Exchange (ETDEWEB)

Due to legal restrictions, the German hard coal mining company Deutsche Steinkohle AG (DSK) is obliged to conduct a monitoring on surface changes (subsidence) caused by mining activity (e.g. topographic surface, groundwater, water, flora and fauna, soil). To fulfill legal demands and to do this effectively, process chains by use of Photogrammetry, Remote Sensing and Geo-Informationssystems (GIS) have been established. Photogrammetric methods are used to generate high resolution Digital Elevation Models (DEM) from which in combination with subsidence data geometrical changes at the topographic surface are deduced. The potential use of active sensors (Laser Scanning and Synthetic Aperture Radar Systems) to deduct DEM has been investigated. The applicability of SAR satellite data to detect and observe subsidence and resulting movements - point wise or with spatial extent - using differential SAR Interferometry (dInSAR) as well as persistent scatterer technology (here: ...

2006-03-15

288

The ternary system cerium-palladium-silicon  

International Nuclear Information System (INIS)

Phase relations in the ternary system Ce-Pd-Si have been established for the isothermal section at 800 deg. C based on X-ray powder diffraction and EMPA techniques on about 130 alloys, which were prepared by arc-melting under argon or powder reaction sintering. Eighteen ternary compounds have been observed to participate in the phase equilibria at 800 deg. C. Atom order was determined by direct methods from X-ray single-crystal counter data for the crystal structures of #tau#_8-Ce_3Pd_4Si_4 (U_3Ni_4Si_4-type, Immm; a=0.41618(1), b=0.42640(1), c=2.45744(7) nm), #tau#_1_6-Ce_2Pd_1_4Si (own structure type, P4/nmm; a=0.88832(2), c=0.69600(2) nm) and also for #tau#_1_8-CePd_1_-_xSi_x (x=0.07; FeB-type, Pnma; a=0.74422(5), b=0.45548(3), c=0.58569(4) nm). Rietveld refinements established the atom arrangement in the structures of #tau#_5-Ce_3PdSi_3 (Ba_3Al_2Ge_2-type, Immm; a=0.41207(1), b=0.43026(1), c=1.84069(4) nm) and ...

2009-09-01

289

Trace elements in the Allende meteorite  

International Nuclear Information System (INIS)

New RNAA determinations of Ba, Sr, Zr, U, Re, Pd, Ag, Zn and Se and INAA measurements of Lu are added to published data for 21 other elements in the same suite of ten samples. On the average, 21 refractory elements are not significantly fractionated from one another. The mean of their enrichment factors relative to C1 chondrites is 17.5 +- 0.4, indicating that the high-temperature condensate inclusions represent 5.7 wt% of the total condensable matter. Os, Ir, Ru, Re and most of the W condensed in one or more refractory siderophile element alloys along with small fractions of the Pd, Co, Au and Ag. The bulk of the Eu and Sr condensed in solid solution in melilite. Sc, Zr, Hf, Ta, U and the remaining REE condensed in a phase whose abundance in the inclusions in negatively correlated with that of melilite, either diopside or one or more minor or trace phases, including perovskite. Ba condensed in a different phase, separately from all these ...

1977-01-01

290

Synthesis and PET imaging of the benzodiazepine receptor tracer [N-methyl-"1"1C]iomazenil  

International Nuclear Information System (INIS)

The central benzodiazepine receptor tracer [N-methyl-"1"1C]iomazenil (Ro 16-0154) was synthesized by alkylation of the desmethyl precursor noriomazenil with ["1"1C]methyl iodide. The ["1"1C]CH_3I (prepared by reduction of ["1"1C]CO_2 with LiAlH_4 followed by reaction with HI) was reacted with noriomazenil inN,N -dimethylformamide and Bu_4N"+OH"- for 1 min at 80 deg. C and purified by HPLC (C_1_8, 34% CH_3CN/H_2O, 7 mL/min). The product was obtained with synthesis time 35 #+-# 5 min (mean #+-# SD, n = 7), radiochemical yield (EOB) 36 #+-# 16%, radiochemical purity 99 #+-# 1%, and specific activity 5100 #+-# 2800 mCi/#mu#mol. Absorbed radiation doses were calculated from previously acquired human biodistribution data. The urinary bladder wall received the highest dose (0.099 mGy/MBq) for 4.8 h voiding interval and the effective dose equivalent was 0.015 mSv/MBq. After i.v. injection of ["1"1C]iomazenil in an adult baboon or healthy human ...

1995-07-01

291

Structure-activity relationships of anthraquinones on the suppression of DNA-binding activity of the aryl hydrocarbon receptor induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin.  

Science.gov (United States)

Anthraquinones are widely present in plant kingdom, and clinically used as laxatives. Environmental contaminants, dioxins, develop various adverse effects through transformation of a cytosolic aryl hydrocarbon receptor (AhR). We investigated the effects of 18 anthraquinones and 7 of their structurally related compounds on transformation of the AhR estimated by its DNA-binding activity in the cell-free system. 1,4-Dihydroxyanthraquinone (quinizarin), 1,5-dihydroxyanthraquinone (anthrarufin), 1,8-dihydroxyanthraquinone (danthron), and 5-hydroxy-1,4-naphthoquinone (juglone) strongly suppressed DNA-binding activity of the AhR induced by 0.1 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), with their IC(50) values around 1 muM. On the other hand, anthraquinone, 2,6-dihydroxyanthraquinone (anthraflavic acid), and 2-hydroxy-1,4-naphthalendione (lawsone) showed moderate effects. Quantitative structure-activity relationships analysis demonstrated that hydroxyl groups at ...

2009-03-01

292

Mechanisms and controlling characteristics of the catalytic oxidation of methane. Technical progress report, June 15, 1990--December 14, 1992  

Energy Technology Data Exchange (ETDEWEB)

We have demonstrated in this work (1) that methane is readily activated at mild conditions (100{degree}C, 1 torr) over a relatively noble metal, Pd. This was observed using a stepped and kinked Pd(679) crystal (1), and other crystal faces are now being investigated to establish whether the cracking of the C-H bond of methane on Pd is structure sensitive or structure insensitive. Oxygen chemisorption is extremely structure sensitive: weakly bonded, highly reactive oxygen overlayers form on Pd(100) surface (2), while strongly bonded, moderately reactive oxygen overlayers form on Pd(111) and Pd(679). Reaction of the weakly bonded oxygen with surface carbide gives rise to CO{sub 2} over clean Pd(100) but to CO over halogen-doped Pd(100) (3--5). The effect of halogens is primarily ensemble-controlling, or oxygen-supply restricting, but long range influence of surface Cl on the strength of the Pd-O bond has also been observed (3). Because the overall ...

1992-12-31

293

Mechanisms and controlling characteristics of the catalytic oxidation of methane  

Energy Technology Data Exchange (ETDEWEB)

We have demonstrated in this work (1) that methane is readily activated at mild conditions (100[degree]C, 1 torr) over a relatively noble metal, Pd. This was observed using a stepped and kinked Pd(679) crystal (1), and other crystal faces are now being investigated to establish whether the cracking of the C-H bond of methane on Pd is structure sensitive or structure insensitive. Oxygen chemisorption is extremely structure sensitive: weakly bonded, highly reactive oxygen overlayers form on Pd(100) surface (2), while strongly bonded, moderately reactive oxygen overlayers form on Pd(111) and Pd(679). Reaction of the weakly bonded oxygen with surface carbide gives rise to CO[sub 2] over clean Pd(100) but to CO over halogen-doped Pd(100) (3--5). The effect of halogens is primarily ensemble-controlling, or oxygen-supply restricting, but long range influence of surface Cl on the strength of the Pd-O bond has also been observed (3). Because the overall ...

1992-01-01

294

Magnetic properties of Ni/sub 100-2x/Mn/sub x/Sb/sub x/-alloys (5less than or equal toxless than or equal to50) - solid and liquid state  

Energy Technology Data Exchange (ETDEWEB)

Magnetothermal measurements up to 1600 K have been made on alloys in the ternary Ni-Mn-Sb system with a constant ratio Mn/Sb=1/1, to which belong the two ferromagnetic Heusler phases Ni/sub 2/MnSb with L2/sub 1/ structure and NiMnSb with C1/sub b/ structure. The susceptibility-temperature curves show the constitution of the vertical section. At high temperatures the susceptibilities obey a Curie-Weiss law. In the solid state the effective magneton number decreases with increasing Mn concentration from 4.9 (Ni/sub 2/MnSb) to 3.8 (NiMnSb). Simultaneously, on the transition from Ni/sub 2/MnSb to NiMnSb there is a strong increase of the susceptibility and of the Curie temperature from 292 to 686 K. In the heterogeneous range between 10 and 20 at.% Mn another phase part appears which is ferromagnetic at room temperature. By a heat treatment it undergoes a distinct development. In the liquid phase, the alloys can be characterized by an extended ...

1989-02-01

295

High performance polymer electrolyte fuel cells with ultra-low Pt loading electrodes prepared by dual ion-beam assisted deposition  

International Nuclear Information System (INIS)

Ultra-low pure Pt-based electrodes (0.04-0.12 mg_P_t/cm"2) were prepared by dual ion-beam assisted deposition (dual IBAD) method on the surface of a non-catalyzed gas diffusion layer (GDL) substrate. Film thicknesses ranged between 250 and 750 A, these are compared with a control, a conventional Pt/C (1.0 mg_P_t_(_M_E_A_)/cm"2, E-TEK). The IBAD electrode constituted a significantly different morphology, where low density Pt deposits (largely amorphous) were formed with varying depths of penetration into the gas diffusion layer, exhibiting a gradual change towards increasing crystalline character (from 250 to 750 A). Mass specific power density of 0.297 g_P_t/kW is reported with 250 A IBAD deposit (0.04 mg_P_t/cm"2 for a total MEA loading of 0.08 mg_P_t/cm"2) at 0.65 V. This is contrasted with the commercial MEA with a loading of 1 mg_P_t_(_M_E_A_)/cm"2 where mass specific power density obtained was 1.18 g_P_t/kW (at 0.65 V), a value typical of ...

2006-06-05

296

Future needs and requirements for AMS "1"4C standards and reference materials  

International Nuclear Information System (INIS)

"1"4C measurement uses a number of standards and reference materials with different properties. Historically the absolute calibration of "1"4C measurement was tied to 1890 wood, through the 'primary' standard of NBS-OxI (produced by the National Bureau of Standards, now NIST - National Institute of Standards and technology) subsequently replaced by NBS-OxII. These are both internationally calibrated and certified materials, whose "1"4C activities are known absolutely. A second tier of materials, often called secondary standards or reference materials, and including internationally recognised materials such as ANU-sucrose (now also IAEA-C6), Chinese - sucrose and the IAEA C1-C6 series, augmented by additional oxalic acid samples are also used routinely. The activity of these materials has been estimated from large numbers of measurements made by many laboratories. Recently, further natural materials from the Third and Fourth International ...

2004-08-01

297

Experimental study and modeling of CH{sub 4}/O{sub 2}/Ar and C{sub 2}H{sub 6}/O{sub 2}/Ar pre-mixing laminar flames; Etude experimentale et modelisation de flammes laminaires de premelange CH{sub 4}/O{sub 2}/Ar et C{sub 2}H{sub 6}/O{sub 2}/Ar  

Energy Technology Data Exchange (ETDEWEB)

New studies are always needed to better determine the physico-chemical processes involved in the combustion of natural gas. The understanding of the reaction mechanisms that lead to the formation of nitrogen oxides or volatile organic compounds requires to identify the inner mechanisms which take place during combustion and in particular the mechanisms of formation of intermediate products. The aim of this study is to analyze the thermal degradation of methane and ethane in low pressure pre-mixed stabilized laminar flames condition, because both of these compounds represent the major part of natural gas composition. The main chemical reaction ways identified in the studied flames and responsible for combustion have been identified after a comparison between experimental results and the computerized simulation performed using an a-priori postulated chemical mechanism. This study stresses on the transfer reaction schemes between the different C1, ...

1996-12-31

298

Evaluation of chitosan/beta-tricalcium phosphate microspheres as a constituent to PMMA cement.  

Science.gov (United States)

Two methods, a traditional emulsion technique and a high voltage electrostatically modified encapsulation system, were used to fabricate degradable chitosan/beta -tricalcium phosphate (beta-TCP) microspheres. The two distinct kinds of microspheres both exhibited good sphericity and the beta-TCP was trapped well inside the chitosan gel. The microspheres prepared by high voltage electrostatic system exhibited a rougher outer surface and narrower size distribution. These microspheres were then used as an added constituent to commercially available PMMA bone cement. Four modified cement composites that were prepared with different composition ratios of the two kinds of chitosan/beta-TCP microspheres that were made from emulsion technique (C1P1 and C2P1) and from a process by a high voltage electrostatic system (EC1P1 and EC2P1) were compared with the PMMA cement (Pure P). The characteristics of these materials indicate that with the addition of ...

2005-06-01

299

Enhancement of electrical conductivity of ion-implanted polymer films  

Energy Technology Data Exchange (ETDEWEB)

The electrical conductivity of ion-implanted films of Nylon 66, Polypropylene (PP), Poly(tetrafluoroethylene) (Teflon) and mainly Poly (ethylene terephthalate) (PET) was determined by DC measurements at voltages up to 4500 V and compared with the corresponding values of pristine films. Measurements were made at 21/sup 0/C +/- 1/sup 0/C and 65 +/- 2% RH. The electrical conductivity of PET films implanted with F/sup +/, Ar/sup +/, or As/sup +/ ions at energies of 50 keV increases by seven orders of magnitude as the fluence increases from 1 x 10/sup 18/ to 1 x 10/sup 20/ ions/m/sup 2/. The conductivity of films implanted with As/sup +/ was approximately one order greater than those implanted with Ar/sup +/, which in turn was approximately one-half order greater than those implanted with F/sup +/. The conductivity of the most conductive film approx.1 S/m) was almost 14 orders of magnitude greater than the pristine PET film. Except for the three PET ...

1985-01-01

300

Design of novel polysaccharidic nanostructures for gene delivery  

Energy Technology Data Exchange (ETDEWEB)

The goal of the present work was to develop a new synthetic nanosystem for gene delivery. For this purpose, we chose two polysaccharides, hyaluronic acid (HA) and chitosan (CS), as the main components of the nanocarrier. Nanoparticles with different hyaluronate:chitosan (HA:CS) mass ratios (0.5:1 and 1:1) and different polymer molecular weights (hyaluronate 170 (HA) or <10 kDa (HAO) and chitosan 125 (CS) or 10-12 (CSO) kDa) could be obtained using an ionic crosslinking method. These nanoparticles were loaded with pDNA and characterized for their size, zeta potential and pDNA association efficiency. Moreover, their toxicity and ability to transfect the model plasmid pEGFP-C1 were evaluated in the cell line HEK 293, as well as their intracellular fate. The results showed that HA:CS nanoparticles have a small size in the range of 110-230 nm, a positive zeta potential of +10 to +32 mV and a very high pDNA association efficiency of 87-99% ...

2008-02-20

301

Dependence of integral cross sections of the 24 MeV #alpha#-particle inelastic scattering on "1"2C, "1"6O, "1"8O, "1"9F, "2"0Ne and "2"2Ne nuclei on level excitation energy  

International Nuclear Information System (INIS)

Inelastic scattering of #alpha#-particles in 22-24 MeV energy range on "1"8o o, "1"9f, "2"0Ne, "2"2Ne nuclei is investigated. Measurements of excitation functions were conducted for the beam of Leningrad University cyclo otron at several angles in 15-165 deg range of laboratory system with 2.5 deg spacing. The error of determining absolute cross sections equals +-20% for "2"2Ne and +-12% for other nuclei. Angular distributions have the differaction character, are similar in form for all nuclei, the values of differential cross- -sections don't exceed the rutherford values. The dependence of integral cross-sections on the energy of level excitation is similar to the exponential d dependence of cross-sections of production of the given element isotopes on the gergy difference of masses of final nuclear products in the reactions of deeply inelastic transfers with heavy ions. The observed isotopic effect in the value of cross-sections of elastic and inelastic #alpha#-particle scattering ...

1983-04-01

302

Deep-ocean record of major late Cenozoic rhyolitic eruptions from New Zealand  

International Nuclear Information System (INIS)

A 12 m.y. record of large rhyolitic eruptions from the Coromandel (CVZ) and Taupo (TVZ) volcanic zones of New Zealand is contained in cores retrieved by Leg 181 of the Ocean Drilling Program. Site 1124, located 670 km from the TVZ, has a maximum of 134 macroscopic tephra layers with a total thickness of 13.18 m. These units, along with between 7 and 63 tephras from 3 other sites, were dated by a combination of magnetostratigraphy, biostratigraphy, isothermal plateau fission track determinations, and geochemical correlation with onshore tephra deposits. Additional time control for the last 3 m.y. came from an orbitally tuned, benthic, oxygen isotope profile for Site 1123. Results extend the incomplete terrestrial record of volcanism by placing the first major rhyolitic eruption in the CVZ at c. 12 Ma, c. 1.6-1 m.y. earlier than previously known. Tephras became thicker and more frequent from the late Miocene into the Quaternary - a trend that ...

2004-09-01

303

Crystal-field analysis of Eu"3"+ energy levels in the new rare-earth R BiY_1_-_xR_xGeO_5 oxide  

International Nuclear Information System (INIS)

Pale colored BiY_1_-_xR_xGeO_5 (R=rare-earth from Pr to Yb) polycrystalline samples exhibit a crystalline phase isostructural with the orthorhombic Pbca (No. 61) structure-type established for BiYGeO_5 and BiYbGeO_5. R occupies a single point site in the host, with the lowest C_1 symmetry. While for Pr and Nd x must be #<=#0.35, for smaller R ions, Sm to Yb, the phase appears for any x content. Detailed crystallographic data for BiErGeO_5 have been determined from the structure refinement of its neutron diffraction profile at room temperature. Optical absorption and photoluminescence measurements at 10 K have been performed for BiEuGeO_5. An initial approach to the parametrization of crystal-field effects on this new host has been provided by results of the semi-empirical Simple Overlap Model, which considers the crystallographic positions of the nearest neighbors around R. Furthermore, the strongly reduced "7F_J_M set of levels of the 4f"6 ...

2002-07-13

304

Chiral logarithms in quenched QCD  

Energy Technology Data Exchange (ETDEWEB)

The quenched chiral logarithms are examined on a 163x28 lattice with Iwasaki gauge action and overlap fermions. The pion decay constant fpi is used to set the lattice spacing, a = 0.200(3) fm. With pion mass as low as {approx}180 MeV, we see the quenched chiral logarithms clearly in mpi2/m and fP, the pseudoscalar decay constant. The authors analyze the data to determine how low the pion mass needs to be in order for the quenched one-loop chiral perturbation theory (chiPT) to apply. With the constrained curve-fitting method, they are able to extract the quenched chiral logarithmic parameter delta together with other low-energy parameters. Only for mpi<=300 MeV do we obtain a consistent and stable fit with a constant delta which they determine to be 0.24(3)(4) (at the chiral scale Lambdachi = 0.8 GeV). By comparing to the 123x28 lattice, they estimate the finite volume effect to be about 2.7% for the smallest pion mass. They also fitted the pion mass to the form for the re-summed ...

2004-08-01

305

Chiral logarithms in quenched QCD  

International Nuclear Information System (INIS)

The quenched chiral logarithms are examined on a 163x28 lattice with Iwasaki gauge action and overlap fermions. The pion decay constant fpi is used to set the lattice spacing, a = 0.200(3) fm. With pion mass as low as #approx#180 MeV, we see the quenched chiral logarithms clearly in mpi2/m and fP, the pseudoscalar decay constant. The authors analyze the data to determine how low the pion mass needs to be in order for the quenched one-loop chiral perturbation theory (chiPT) to apply. With the constrained curve-fitting method, they are able to extract the quenched chiral logarithmic parameter delta together with other low-energy parameters. Only for mpi<=300 MeV do we obtain a consistent and stable fit with a constant delta which they determine to be 0.24(3)(4) (at the chiral scale Lambdachi = 0.8 GeV). By comparing to the 123x28 lattice, they estimate the finite volume effect to be about 2.7% for the smallest pion mass. They also fitted the pion mass to the form for the re-summed ...

2004-08-01

306

Analysis of the D+ --> K- pi+ e+ nu_e decay channel  

CERN Document Server

Using 347.5 fb-1 of data recorded by the BABAR detector at the PEP-II electron-positron collider, 244*10^3 signal events for the D+ --> K- pi+ e+ nu_e decay channel are analyzed. This decay mode is dominated by the \\bar{K}^*(892)^0 contribution. We determine the \\bar{K}^*(892)^0 parameters: m_{K^*(892)^0}=(895.4 +- 0.2 +- 0.2) MeV/c^{2}, \\Gamma^0_{K^*(892)^0}=(46.5 +- 0.3 +- 0.2) MeV/c^{2} and the Blatt-Weisskopf parameter $r_{BW}=2.1 +- 0.5 +- 0.5 (GeV/c)^{-1} where the first uncertainty comes from statistics and the second from systematic uncertainties. We also measure the parameters defining the corresponding hadronic form factors at q^{2}=0 (r_{V} = V(0) / A_{1}(0)=1.463 +- 0.017 +- 0.031, r_{2} = A_{2}(0) / A_{1}(0) = 0.801 +- 0.020 +- 0.020) and the value of the axial-vector pole mass parameterizing the q^2 variation of A_{1} and A_{2}: m_{A}=(2.63 +- 0.10 +- 0.13) GeV/c^{2}. The S-wave fraction is equal to (5.79 +- 0.16 +- 0.15)%. ...

2010-01-01

307

A study on the recovery of radiation hardening of PWR pressure vessel steel using microhardness and positron annihilation  

International Nuclear Information System (INIS)

A post-irradiation annealing study was conducted with use of reactor pressure vessel(RPV) steel A533B C1.1 base metal irradiated to a dose of 4.84x10"1"8 n/cm"2 at about 380 deg C. Microhardness and positron annihilation (PA) methods were used to obtain better understanding of the recovery of radiation hardening. Isochronal anneal experiments indicated that two recovery processes occur during annealing of irradiated specimens. The first recovery process occurs in the temperature of 280-305 deg C. The variations of Ip, Iw and R parameters indicated that the formation of vacancy clusters by vacancy aggromeration and the annihilation parameters measured indicated that the dissolution of carbon atoms decorated around vacancy-type defects and possible precipitates, and the annihilation of monovacancies give rise to the second recovery process. It was further indicated that radiation anneal hardening (RAH) in the range of 305-405 deg C between the ...

308

A model for the devolatilization of a coal particle sufficiently large to be controlled by heat transfer  

Energy Technology Data Exchange (ETDEWEB)

This study follows previous experimental work showing that the shrinking-core model applies to the pyrolysis (i.e., heating in the absence of oxygen) of particles (diam.{approx}14 mm) of a bituminous coal or a lignite in a fluidized bed at 700-950 {sup o}C. These experimental facts are in accord with the production of volatile matter being endothermic and not thermoneutral, as often assumed. Also, the rate at which volatile matter is produced in the presence of oxygen (i.e., devolatilization) or in its absence (pyrolysis) is demonstrated here to be controlled not at all by mass transfer, but by heat conduction to a moving reaction front inside a coal particle, provided its diameter exceeds {approx}3 mm. The resulting steady-state model of devolatilization indicates that six dimensionless groups are required to describe the rate of(I)coal->char+volatile matter for a nonfragmenting and nonswelling coal. This reaction occurs for a total time of c{sub 1}r{sub 0}+c{sub 2}r{sub 0}{sup ...

2006-08-15

309

The ternary system cerium-palladium-silicon  

Science.gov (United States)

Phase relations in the ternary system Ce-Pd-Si have been established for the isothermal section at 800 deg. C based on X-ray powder diffraction and EMPA techniques on about 130 alloys, which were prepared by arc-melting under argon or powder reaction sintering. Eighteen ternary compounds have been observed to participate in the phase equilibria at 800 deg. C. Atom order was determined by direct methods from X-ray single-crystal counter data for the crystal structures of tau{sub 8}-Ce{sub 3}Pd{sub 4}Si{sub 4} (U{sub 3}Ni{sub 4}Si{sub 4}-type, Immm; a=0.41618(1), b=0.42640(1), c=2.45744(7) nm), tau{sub 16}-Ce{sub 2}Pd{sub 14}Si (own structure type, P4/nmm; a=0.88832(2), c=0.69600(2) nm) and also for tau{sub 18}-CePd{sub 1-x}Si{sub x} (x=0.07; FeB-type, Pnma; a=0.74422(5), b=0.45548(3), c=0.58569(4) nm). Rietveld refinements established the atom arrangement in the structures of tau{sub 5}-Ce{sub 3}PdSi{sub 3} (Ba{sub 3}Al{sub 2}Ge{sub 2}-type, Immm; a=0.41207(1), b=0.43026(1), ...

2009-09-15

310

Carbon monoxide - hydrogen combustion characteristics in severe accident containment conditions. Final report  

International Nuclear Information System (INIS)

Carbon monoxide can be produced in severe accidents from interaction of ex-vessel molten core with concrete. Depending on the particular core-melt scenario, the type of concrete and geometric factors affecting the interaction, the quantities of carbon monoxide produced can vary widely, up to several volume percent in the containment. Carbon monoxide is a combustible gas. The carbon monoxide thus produced is in addition to the hydrogen produced by metal-water reactions and by radiolysis, and represents a possibly significant contribution to the combustible gas inventory in the containment. Assessment of possible accident loads to containment thus requires knowledge of the combustion properties of both CO and H_2 in the containment atmosphere. Extensive studies have been carried out and are still continuing in the nuclear industry to assess the threat of hydrogen in a severe reactor accident. However the contribution of carbon monoxide to the combustion threat has received less ...

1994-10-19

311

Biogenic emissions of isoprenoids and NO in China and comparison to anthropogenic emissions  

International Nuclear Information System (INIS)

In this study, a regional dynamical model (WRF) is used to drive biogenic emission models to calculate high resolution (10 x 10 km) biogenic emissions of isoprene (C_5H_8), monoterpenes (C_1H_1_6), and nitric oxide (NO) in China. This high resolution biogenic inventory will be available for the community to study the effect of biogenic emissions on photochemical oxidants in China. The biogenic emissions are compared to anthropogenic emissions to gain insight on the potential impact of the biogenic emissions on tropospheric chemistry, especially ozone production in this region. The results show that the biogenic emissions in China exhibit strongly diurnal, seasonal, and spatial variations. The isoprenoid (including both isoprene and monoterpenes) emissions are closely correlated to tree density and strongly vary with season and local time. During winter (January), the biogenic isoprenoid emissions are the lowest, resulting from lower temperature ...

2006-12-01