WorldWideScience
1

Statistical treatment of the inner M-shell excitation in heavy ion-atom collisions  

Energy Technology Data Exchange (ETDEWEB)

A statistical treatment has been applied to interpret the experimental data on the Xe M-shell vacancy production in slow 1.05 MeV Xe-Xe collisions and is shown to give better agreement with experiment than that of the molecular-orbital models.

1983-06-27

2

Compressed-shell integrity measurements in spherical implosion experiments  

International Nuclear Information System (INIS)

The shell integrity near peak compression of spherical implosions using the 60-beam, 30-kJ UV OMEGA laser system [Opt. Commun. 133, 495 (1997)] has been measured. Hot core emission backlights a shell with a thin titanium-doped layer that is imaged at x-ray photon energies above and below the titanium K edge. The x-ray intensity ratio between the two images is related to perturbations in the cold, or absorbing, part of the shell. The measured cold-shell areal-density modulations, integrated over the time of peak compression, are of the order of 25% to 50% with nonuniformity spectra peaked at spatial wavelengths of 30 to 50 #mu#m and with the smallest detectable nonuniformity features extending down to spatial wavelengths of 12 to 15 #mu#m. Hot-shell areal-density modulations of the emitting part of the shell (inner edge) ...

2001-06-01

3

Measurement of M shell X-ray production cross sections and fluorescence yields for the elements in the atomic range 70#<=#Z#<=#92 at 5.96 keV  

International Nuclear Information System (INIS)

Total M X-ray cross sections for 12 elements in atomic range 70#<=#Z#<=#92 were measured at 5.96 keV Mn K X-ray photon energy. The average M shell fluorescence yields (anti #omega#_M) of these elements have also been observed using the presently measured cross section values and the theoretical M shell photoionisation cross section values. (orig.).

4

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

5

Coincidence measurements of M-shell excitation in slow Xe-Xe collisions  

Energy Technology Data Exchange (ETDEWEB)

Ion-photon and ion-Auger-electron coincidence measurements have been performed to study the impact parameter dependence of Xe M-shell excitation in 1.05 MeV Xe/sup 3 +/-Xe collisions. The experimental results are found to be consistent with the prediction of the molecular orbital model of atomic collisions. The average fluorescence yield for the Xe M shell is found to be strongly dependent on the impact parameter. This is ascribed to the production of highly charged Xe ions in close collisions.

1982-07-14

6

Angular dependence from L_3-subshell to M-shell vacancy transfer probabilities for heavy elements using EDXRF technique  

International Nuclear Information System (INIS)

Angular dependence from L_3-subshell to M-shell vacancy transfer probabilities for selected heavy elements from Au to U have been measured by using a Si(Li) detector coupled to a model 1024 computerized multi-channel analyzer. Because the angular dependence from L_3-subshell to M-shell vacancy transfer probabilities is not found in the literature, to the best of our knowledge there are no experimental values for worked elements. Therefore, the results for the elements obtained in the present study constitute the first experimental measurements; the comparison has been not made with other experimental and theoretical results. It has been observed that angular dependence from L_3-subshell to M-shell vacancy transfer probabilities increase with increasing cos #theta#.

2008-07-01

7

M shell x-ray emission in Pb, Th and U due to L_3 to M sub shell transfer of vacancies  

International Nuclear Information System (INIS)

M shell x-ray production cross sections in thick targets of Pb, Th and U by K x-rays of Rb, Nb and Mo respectively have been measured. As the incident K x-ray energies are above the L_3 edge but below L_2 edge energies of the respective target elements under reference, the M x-rays are produced not only due to direct interaction of incident photons with M shell electrons but also due to the shift of the L_3 subshell vacancies to the M shell. The experiment has been performed using a double reflection geometrical setup with a 1 Curie"2"4"1Am gamma ray source and a Si (Li) x-ray spectrometer. The measured values have been compared with those calculated using known values of M and L_3 subshell photoionisation cross sections and fluorescence yields etc., wherever possible. The component of the percentage contribution due to ...

8

Effects of indirect ionization on the charge state distributions observed with highly charged ion sources  

Energy Technology Data Exchange (ETDEWEB)

Presently, most charge state distributions produced with highly charged ion sources are predicted with models that approximate the ionization process with the Lotz formula. The Lotz ionization cross sections decrease approximately geometrically with increasing charge state except for ions with very few vacancies, for ions with very few electrons, and for electron impact energies which barely exceed the ionization energy. The geometrical decrease causes these models to predict a maximum abundance for most of the charge states, which is only weakly dependent on the charge state. Experimental results, however, yield much higher abundances for ions with an empty M shell than ions with a partly filled M shell. This difference is explained with indirect ionization processes that are neglected by the Lotz approximation, and normally can be neglected for the ionization of the L shell, but ...

2000-02-01

9

Schematic model for the differences between neutron and proton quadrupole deformation parameters in open-shell nuclei  

Energy Technology Data Exchange (ETDEWEB)

The schematic model is extended to open-shell nuclei. The quasiparticle random-phase approximation plus core polarization are used to calculate multipole matrix elements M/sub n/ and M/sub p/. Calculated trends in the ratio of deformation parameters ..beta../sub n//..beta../sub p/ are compared with experimental ratios for several sets of isotopes and isotones. The systematics indicate a rather abrupt change toward equality of ..beta../sub n/ and ..beta../sub p/ when N or Z is changed from a closed-shell value.

1984-01-16

10

The semiclassical approximation for L- and M-shell Coulomb ionization by heavy charged particles  

International Nuclear Information System (INIS)

The semiclassical approximation with straight-line trajectories is applied to the Coulomb ionization of K, L and M shells by heavy charged particles. The calculational aspects are discussed in detail. Scaling relations for the experimentally relevant quantities are derived. The theoretical predictions are compared with experiment. The relation of the present work to the earlier results of the semiclassical approximation and partial-wave Born approximation is discussed in detail. (author).

11

Measurements of K-shell x-ray production cross sections and K to L and M-shell radiative vacancy transfer probabilities for Nd, Eu, Gd, Dy and Ho at excitation with 59.5 keV photons in an external magnetic field  

International Nuclear Information System (INIS)

The effect of the #+-# 0.75 T external magnetic field on the K_#alpha#_1, K_#alpha#_2, K_#beta#_'_1 and K_#beta#_'_2 x-ray production cross sections and radiative vacancy transfer probabilities from K-shell to L2 and L3 subshells and M-shell for ferromagnetic Nd, Gd and Dy and paramagnetic Eu and Ho have been investigated, using the 59.5 keV incident photons. K-shell fluorescence yields and K x-ray intensity ratios for these elements have been determined in the external magnetic field also. The K x-rays from different targets were detected using a high-resolution Si(Li) semiconductor detector. For B = 0, the present experimental results were compared with the experimental and theoretical data in the literature. The results show that K-shell fluorescence parameters such as photoionization cross section, fluorescence yield, radiation rates, vacancy transfer probabilities and spectral linewidth can change ...

2006-06-19

12

M-shell x-ray production by 0.6--4.0-MeV protons in ten elements from hafnium to thorium  

International Nuclear Information System (INIS)

M-shell x-ray production cross sections for selected heavy elements, namely, _7_2Hf, _7_3Ta, _7_4W, _7_5Re, _7_6Os, _7_7Ir, _7_8Pt, _7_9Au, _8_3Bi, and _9_0Th, were measured for protons of energy 0.6--4.0 MeV. The experimental results are compared with the predictions of the first Born and semiclassical approximations for M-shell ionization; these data are also compared with the theory that accounts for the projectile's energy loss and Coulomb deflection as well as for the target's M-shell electron perturbed stationary state and relativistic nature (ECPSSR). Generally, fair agreement between the data and the ECPSSR theory is found. Some systematical discrepancies observed for the lightest elements (Hf, Ta, and W) are explained as possible ambiguities in the M-shell Coster-Kronig factors and fluorescence yields, which were used to convert theoretical M-subshell ionization cross ...

13

Shell coal gasification plant (SCGP-1) environmental performance results  

Energy Technology Data Exchange (ETDEWEB)

Environmental studies in slip-stream process development units at SCGP-1, Shell's advanced coal gasification demonstration plant, located near Houston, Texas, have demonstrated that the gas and water effluents from the Shell Coal Gasification Process (SCGP) are environmentally benign on a broad slate of coals. This report presents the results of those environmental studies. It contains two major subjects, which describe, respectively, the experiments on gas treating and the experiments on water treating. Gas treatment focused on the performance of aqueous methyldiethanolamine (MDEA) and sulfinol-M. 8 refs., 24 figs., 13 tabs.

1991-07-01

14

K beta X-ray transition energies of M-shell-ionized ions of Ti through Ni in a plasma  

Energy Technology Data Exchange (ETDEWEB)

K beta X-ray lines from partially M-shell-ionized ions of titanium through nickel which are produced in vacuum-spark plasmas have been observed systematically for the first time, using a high-resolution curved-crystal spectrometer. Each K beta line is clearly separated into its corresponding charge state. As a result, it is possible to measure the K beta-type transition energies of the M-shell-ionized ions. The transition energies accurately determined are compared with those calculated for iron ions, and the agreement is excellent except for ions having some additional 3d outer-shell electrons or 3s inner-shell vacancies. The square root of the K beta transition frequency is expressed as a linear function of the nuclear charge for isoelectronic sequences. The effective nuclear charges have been also determined for each K beta transition. The 3p electrons do not affect the effective nuclear charges. 10 ...

1985-05-01

15

Effects of relativity and wave functions on atomic L- and M-shell ionization by protons  

Energy Technology Data Exchange (ETDEWEB)

Atomic L- and M-shell ionization cross sections by protons have been calculated in the plane-wave Born approximation for /sub 79/Au and /sub 92/U with incident energy from 0.1 to 3 MeV with use of relativistic and nonrelativistic Hartree-Slater wave functions. These results are compared with those from the screened hydrogenic model to study the effects of relativity and wave functions. The relativistic and wave-function effects are found to operate in opposite directions. For M/sub 1,2,3/-subshell cross sections, severe cancellations occur between these two factors.

1984-10-01

16

Theoretical transition energies, lifetimes and fluorescence yields of multiply ionized silicon  

Energy Technology Data Exchange (ETDEWEB)

Theoretical x-ray transition energies, lifetimes and partial multiplet fluorescence yields are presented for all spectroscopic terms of electron configurations with a single K-shell vacancy and varying number of electrons in the L-shell and M/sub 1/-subshell for multiply-ionized silicon. 9 tables.

1982-01-01

17

Measurements and calculations of M-shell X-ray production in Er, Yb and Lu by 0.75-6 MeV He ions  

Energy Technology Data Exchange (ETDEWEB)

M-shell X-ray production cross sections for the light rare-earth elements of {sup 68}Er, {sup 7}Yb and {sup 71}Lu have been measured for incident {sup 4}He{sup +} ions in the energy range from 0.75 to 6 MeV. The measured X-ray production cross sections are compared to the predictions of the First Born approximation, the ECPSSR theory and the ECUSAR theory. A comparison of the ytterbium M-shell X-ray production cross sections with these theories is made for two different sets of fluorescence yields and Coster-Kronig factors that are further modified for multiple ionization.

2005-12-15

18

On the dependence of some helium shell flash characteristics on core mass  

Energy Technology Data Exchange (ETDEWEB)

A theoretical derivation of the intershell mass--core mass relation of Paczynski is attempted. Formulae developed by Sugimoto and Fujimoto are extended to less massive (m/sub c/< or approx. =1) cores.

1980-08-15

19

Possible influence of vacuum polarization on Q/sub 1//sub //sub s/ in muon catalyzed D-T fusion  

Energy Technology Data Exchange (ETDEWEB)

The vacuum polarization splitting of the M-shell states in muonic hydrogen can have a profound influence on the muonit de-excitation cascade in deuterium and tritium targets. The cascade also shows sensitive dependence on the precise rate of transfer processes between certain excited muonic deuterium and tritium atoms. Recent experimental data, where a much greater population of the (d..mu..) qs state (1/sub 1//sub //sub s/) was found than previously predicted, can be explained if the transfer rates from the (d..mu..) M-shell are assumed to be strongly suppressed.

1988-12-27

20

Photon angular distribution of radiative electron capture into the M shell of He-like uranium ions at 110-140 MeV/u  

Energy Technology Data Exchange (ETDEWEB)

Measurements of the photon angular distribution of Radiative Electron Capture into the M shell have been performed with He-like uranium ions in the range 110-140 MeV/u. In addition, L REC was studied at a projectile energy of 140 MeV/u. In both cases, the experimental data show an asymmetry around 90 and agree well with a fully relativistic theory. (orig.) 15 refs.

1995-10-01

21

L-subshell and total M-shell X-ray production cross sections of Ta, W, Pt, Au, Pb and Bi by 0.7-2.4 MeV protons  

International Nuclear Information System (INIS)

The L-subshell and total M-shell X-ray production cross sections of Ta, W, Pt, Au, Pb and Bi have been measured by protons of energy between 0.7 and 2.4 MeV. The obtained results for X-ray production cross sections have been compared with the existing experimental data, prediction of the ECPSSR theory and also with fitted empirical cross sections of Strivay and Weber.

2006-06-01

22

Ion-induced M X-ray emission from heavy lanthanides  

International Nuclear Information System (INIS)

Thick targets of several heavy lanthanide (Ho-Lu) compounds were bombarded by protons and "3He ions of 3 MeV/amu, and M_#alpha# and M_#beta# X-rays were measured with a crystal spectrometer. Ionization probabilities of the N-shell for zero impact parameter were obtained from the X-ray intensity ratio for proton and "3He ion impacts. A shell dependence of the ionization probability was found in a scaling plot. X-ray spectra of lanthanide compounds were compared and no chemical effect was observed. This result is considered to be due to the fact that the main component of M_#alpha# and M_#beta# lines is for radiative transition after the refilling of the 4f orbit (3d"-"14f"n"+"1 #-># 4f"n) where n denotes the number of 4f electrons of the target atom before ionization. (orig.).

1987-12-01

23

Transition rates of electrons in superheavy elements  

International Nuclear Information System (INIS)

Transition rates for electrons in the superheavy elements Z = 114, 126, 134, 145, 164 and 173 are calculated. K, L and M-shells are considerd as final states. The 2s - 1s stransition of multipolarity M1 is dominant for Z = 173 with a transition time of 10"-"1"8s. The radial expectation values and #sq root# are given. (orig.).

24

Influence of temperature and velocity of 92% sulfuric acid on anodic behavior of stainless steels  

Energy Technology Data Exchange (ETDEWEB)

This paper investigates the anodic behavior of steels 12Kh18N10T, 10Kh17N13M2T, 08Kh22N6T, and 08Kh21N6M2T in 92% sulfuric acid. The aim of the study was to determine the parameters for anodic protection of shell-and-tube coolers. Results of the study are presented.

1986-03-01

25

M X-ray production in Nd, Gd, Ho and Lu by 1-6 MeV lithium ions  

Energy Technology Data Exchange (ETDEWEB)

M-shell X-rays of the rare-earth elements {sub 60}Nd, {sub 64}Gd, {sub 67}Ho and {sub 71}Lu were measured for lithium ion bombardment in the energy range 1.0-6.0 MeV. The M-shell X-rays with energies of 0.978-1.631 keV were detected with a LINK analytical detector. The efficiency of the detector was determined by using the known atomic-field bremsstrahlung cross-sections from low energy electron beams and K-shell X-ray measurements with light projectiles. The measured cross-sections are compared to the predictions of the first Born approximation and the ECPSSR (energy loss and Coulomb deflection effects, perturbed stationary state approximation with relativistic correction) theories. The best theoretical description of the present data is given by the ECPSSR theory, even though the discrepancy between data and theory is increasing at higher projectile energies.

2004-06-01

26

The assessment of defects in thin shells subject to secondary stress  

International Nuclear Information System (INIS)

This paper is concerned with the fracture analysis of thin cylindrical shells subject to secondary bending stresses with some degree of elastic follow-up. A P.Y.F.M. failure assessment route is utilised for an initial investigation. Results are presented graphically and indicate the differences obtained by considering the stresses as primary or secondary in nature. The Jsup(*) contour integral is computed from the results of a non-linear finite element analysis of a thermally loaded cracked cylinder. Comparison is made between Jsup(*) and the P.Y.F.M. failure criteria demonstrating the degree of conservatism in the latter. It is observed that LEFM may be appropriate for moderate load levels but that the elastic follow-up of the structure causes enhancement of Jsup(*) for higher loads, at which stage LEFM becomes non-conservative. (orig.).

1981-08-21

27

Inelastic-energy-loss measurements of multiple N- and M-shell excitations in 0.3- to 1.2-MeV Xe"+-Xe collisions  

International Nuclear Information System (INIS)

The inelastic energy losses for single collisions of Xe"+ ions with Xe targets have been measured for incident ion energies from 0.3 to 1.2 MeV and for scattering angles from 3"0 to 20"0. The energy losses were found to range from 1 to 11 keV with distinct steps at distances of closest approach of 0.22 and 0.12 A. By comparing these data with earlier ionization data by the same authors these steps are shown to be caused by M-shell excitation. Other excitations observed in the ionization data may be attributed to N-shell excitation. The distances of closest approach at which these excitations occur agree well with calculations by Eichler and Wille and co-workers, giving further evidence of the usefulness of Fano and Lichten's one-electron molecular model and these calculations.

28

Ion-induced M X-ray emission from heavy lanthanides  

Energy Technology Data Exchange (ETDEWEB)

Thick targets of several heavy lanthanide (Ho-Lu) compounds were bombarded by protons and /sup 3/He ions of 3 MeV/amu, and M/sub ..cap alpha../ and M/sub ..beta../ X-rays were measured with a crystal spectrometer. Ionization probabilities of the N-shell for zero impact parameter were obtained from the X-ray intensity ratio for proton and /sup 3/He ion impacts. A shell dependence of the ionization probability was found in a scaling plot. X-ray spectra of lanthanide compounds were compared and no chemical effect was observed. This result is considered to be due to the fact that the main component of M/sub ..cap alpha../ and M/sub ..beta../ lines is for radiative transition after the refilling of the 4f orbit (3d/sup -1/4f/sup n+1/ -> 4f/sup n/) where n denotes the number of 4f electrons of the target atom before ionization.

1987-12-01

29

Isomeric states and spin polarization in A approx. 90 nuclei  

Energy Technology Data Exchange (ETDEWEB)

The observed inhibition of M4 transitions in A approx. 90 nuclei has represented a long standing theoretical problem. In particular by calculating first- and second-order configuration mixing contributions to the inhibited M4 lifetimes of /sup 89/Y and /sup 87/Sr, it is found that the first-order perturbative treatment of the residual interaction usually used in shell-model calculations is unjustified in this case. Using random-phase approximation techniques, the renormalization effects of collective (''giant'') M4 resonances in /sup 88/Sr on the low energy M4 transitions in /sup 89/Y and /sup 87/Sr are investigated. It is concluded that the observed retardation of M4 lifetimes in these nuclei is consistent with the manifestation of nuclear spin polarization.

1980-04-01

30

The large N limit of C/Z{sub N} and supergravity  

Energy Technology Data Exchange (ETDEWEB)

The C/Z{sub N} orbifold of type II string theory has localized tachyons with m{sup 2} ranging from -1+1/N to -2/N in units of 2/{alpha}'. We show that by restricting attention to the lightest tachyons it is possible to take a zero-slope limit where N is taken to infinity while N{alpha}' is held fixed. This is done by applying Buscher duality in the angular direction of the cone to obtain a supergravity solution on which the tachyons are gravitational instabilities. In this picture, supergravity provides a natural off-shell description of the tachyonic interactions. For example, the three-point couplings can be read off easily (to leading order in 1/N) from the supergravity action, and are in agreement with the on-shell couplings computed using CFT techniques. (author)

2005-02-01

31

Precise radiometry: Some recent aspects of fruitful interaction with atomic physics  

International Nuclear Information System (INIS)

Modern radiometric analytics demands a complex consideration of nuclear and electron shell processes, if more pretentious aims are envisaged. As an example the small variation of decay rates of radionuclides presents possibilities for information on chemical situations of decaying atoms. In principle this phenomenon is well known since many years, but now the situation is such that, e.g. in /sup 99m/Tc internal conversion, a full agreement of the difficult experiments and the respective theory was established. The secondary emission of X-rays as a consequence of high excitation of electron shells in combination with nuclear transitions supplies another example for a methodical progress of radiometry. Investigations on "5"1Cr as an electron capture nuclide have shown that chemically induced variations of the K/sub #alpha#/ to K/sub #beta#/ X-ray intensity ratio is at least qualitatively understood. (author).

1986-01-01

32

FG Sge at the stage of dust shell ejection  

British Library Electronic Table of Contents (United Kingdom)

New photometric observations of the variable star FG Sge, a rapidly evolving planetary nebula nucleus, were performed in 2003?2008. On 230 nights, we obtained 86 UBV and 155 BV RI (or R c , I c ) magnitude estimates. The maximum amplitude of the V-band light variations was >8 m . Six deep minima and four high maxima were observed. Analysis of the light curve has shown that the pulsation period of the star remained constant since 1991 and was P = 115 days. We have studied the wavelength dependence of the extinction at various phases of the light curve. The blueing of the B-V color at deep minima is interpreted as the result of light scattering in the circumstellar dust shell of the star formed by preceding dust ejections since 1992. Our spectroscopic observations performed on nine nights in...

2009-01-01

33

Conversion of ortho-para H2O isomers in water and a jump in erythrocyte fluidity through a microcapillary at a temperature of 36.6?0.3?C  

British Library Electronic Table of Contents (United Kingdom)

A mechanism is proposed for the previously observed [1] jump in erythrocyte fluidity through a microcapillary 1.3 ?m in diameter at a temperature of 36.6?0.3?C. Our interpretation is based on the experimental evidence both for existence of ortho and para H2O isomers in water and on spin-selective interaction of proteins with para H2O isomers as hydration shells of biomolecules are being formed [2]. It is important that the formation of hydration shells of proteins and DNA in aqueous solutions is accompanied by an increase in the Brillouin shift to 0.4 cm?1 (?0.25 cm?1 in water), which points to the formation of icelike structures. We believe that the coincidence of the translational energy kT of the Brownian motion and the energy of the rotational quanta for the 313?202 transition of para ...

2009-01-01

34

Biosorption of lead by citrobacter freundii immobilized on hazelnut shells  

Energy Technology Data Exchange (ETDEWEB)

Biosorption of lead from aqueous solutions by living and immobilized cell of C. freundii was examined as a function of metal concentration in a batch laboratory bioreactor. Lead concentrations were analyzed using Atomic Absorption Spectrophotometer (AAS). X-ray Energy Dispersion (EDX) analyses were made in order to determine the accumulation of lead on the cells and shell surfaces. Before and after the experiments the biomaterials and adsorbents were examined by Scanning Electron Microscopy (SEM). Biosorption was detected over a range of initial lead concentrations from 25{times}10{sup -3} to 200{times}10{sup -3} kg/m{sup 3}. 15 refs., 4 figs.

1996-12-31

35

The optical emission nebulae in the vicinity of WR 48 (Theta Mus); True Wolf-Rayet ejecta or unconnected supernova remnant?  

CERN Document Server

During searches for new optical Galactic supernova remnants (SNRs) in the high resolution, high sensitivity Anglo-Australian Observatory/United Kingdom Schmidt Telescope (AAO/UKST) HAlpha survey of the southern Galactic plane, we uncovered a variety of filamentary and more diffuse, extensive nebular structures in the vicinity of Wolf-Rayet (WR) star 48 (Theta Muscae), only some of which were previously recognised. We used the double-beam spectrograph of the Mount Stromlo and Siding Spring Observatory (MSSSO) 2.3-m to obtain low and mid resolution spectra of selected new filaments and structures in this region. Despite spectral similarities between the optical spectra of WR star shells and SNRs, a careful assessment of the new spectral and morphological evidence from our deep HAlpha imagery suggests that the putative shell of Theta Mus is not a WR shell at all, as has been commonly accepted, but is ...

2009-01-01

36

Design of the ZTH vacuum liner  

Energy Technology Data Exchange (ETDEWEB)

The current status of the ZTH vacuum liner design is covered by this report. ZTH will be the first experiment to be installed in the CPRF (Confinement Physics Research Facility) at the Los Alamos National Laboratory and is scheduled to be operational at the rated current of 4 MA in 1992. The vacuum vessel has a 2.4 m major radius and a 40 cm minor radius. Operating parameters which drive the vacuum vessel mechanical design include a 300 C bakeout temperature, an armour support system capable of withstanding 25 kV, a high toroidal resistance, 1250 kPa magnetic loading, a 10 minute cycle time, and high positional accuracy with respect to the conducting shell. The vacuum vessel design features which satisfy the operating parameters are defined. The liner is constructed of Inconel 625 and has a geometry which alternates sections of thin walled bellows with rigid ribs. These composite sections span between pairs of the 16 diagnostic stations to ...

1987-01-01

37

Multiple-shell planetary nebula formation  

Energy Technology Data Exchange (ETDEWEB)

Predictions of the combination of our recent model for the formation of planetary nebulae (due to a diverging pulsational instability) together with nuclear-burning shell flashing, with regard to formation of multiple shells, are explored and discussed.

1980-11-15

38

A cryocondensation pump for the DIII-D Advanced Divertor Program  

Energy Technology Data Exchange (ETDEWEB)

A cryocondensation pump was designed for the baffle chamber of General Atomics DIII-D tokamak and will be installed in the fall of 1992. The purpose of the pump is to study plasma density control by pumping the divertor. The pump is toroidally continuous, approximately 10 m long and located in the lower outer corner of the vacuum chamber of the machine. It consists of a 1 m{sup 2} liquid helium-cooled surface surrounded by a liquid nitrogen-cooled shield to limit the heat load on the helium-cooled surface. The liquid nitrogen-cooled surface is surrounded by a radiation/particle shield to prevent energetic particles from impacting and releasing condensed water molecules. A thermal enhancement coating was applied to the nitrogen shell to lower the maximum temperature of the shell. The coating is non-continuous to keep the toroidal electrical resistance high. The whole pump is supported off the ...

1992-03-01

39

Hydropower. Shell Hydrogen Knowledge Centre for the hydrogen future; Waterkracht. Shell Hydrogen kenniscentrum voor de waterstoftoekomst  

Energy Technology Data Exchange (ETDEWEB)

The activities of Shell Hydrogen in the development of a hydrogen economy are outlined. Attention is paid to the use of hydrogen in electric cars and in homes, different types of fuel cells, and the catalytic partial oxidation (CPO) process of Shell to produce hydrogen

1999-09-01

40

Hydropower. Shell Hydrogen Knowledge Centre for the hydrogen future; Waterkracht. Shell Hydrogen kenniscentrum voor de waterstoftoekomst  

Energy Technology Data Exchange (ETDEWEB)

The activities of Shell Hydrogen in the development of a hydrogen economy are outlined. Attention is paid to the use of hydrogen in electric cars and in homes, different types of fuel cells, and the catalytic partial oxidation (CPO) process of Shell to produce hydrogen.

1999-10-01

42

Shell-model predictions for electromagnetic properties of N = 50 nuclei  

Energy Technology Data Exchange (ETDEWEB)

Predictions for E2, M1, and M4 transition rates and moments, together with examples of transition-charge densities, are presented for states of N = 50 nuclei. These predictions are based on one-body spectroscopic amplitudes obtained from the wave functions of a new N = 50 shell-model calculation which incorporates the 0f/sub 5/2/, 1p/sub 3/2/, 1p/sub 1/2/, and 0g/sub 9/2/ single-particle orbits and an empirically determined effective Hamiltonian for this space. The predictions are compared with experimental data, first in order to evaluate how well the model space, as applied by this Hamiltonian, accounts for observations, and then to assess the importance of configurations excluded from the model space and to determine the values of the operator renormalizations (effective charges and effective g factors) which optimally map the theoretical results onto the corresponding experimental values.

1988-12-01

43

Relativistic mean field study of light nuclei  

International Nuclear Information System (INIS)

Bulk properties such as the binding energies, r.m.s. radii and deformation parameters are calculated for the light (Z=2-8) even-mass nuclei using deformed relativistic mean-field theory. A comparison between L1, NL1 and NL2 parameter sets are given. The effects of pairing for open-shell nuclei have been investigated. The calculation is extended to nuclei near the proton- and neutron-drip line. Reasonable agreement with experiment is achieved for NL1 and NL2 parameter sets. (orig.).

44

Recent observations of Cassiopeia A  

International Nuclear Information System (INIS)

During the last few years radio and X-ray astronomers have produced high-resolution imagery of the remnant of Cas A. Since the most recent published optical photographs of Cas A date back to 1975 it seemed worthwhile to present new optical results based on plates obtained with the 5-m Hale telescope in 1976, 1977, and 1980. The major changes that have taken place in Cas A during the last decade are: (1) A broken shell of fast-moving knots has formed along the southern and SW rim of the remnant and (2) A number of blue (oxygen-rich) filaments have developed to the north of the centre of Cas A. (Auth.).

45

Evaluation of prompt neutron spectra for americium isotopes by multimodal Madland-Nix model  

Energy Technology Data Exchange (ETDEWEB)

The prompt neutron spectra of {sup 241}Am, {sup 242m}Am, and {sup 243}Am were evaluated for the next version of Japanese Evaluated Nuclear Data Library, using the methodology developed by the authors. The method is based on the Madland-Nix theory with some improvements to consider the multimodal nature of the fission process, and shell effects on the level density parameters and the neutron multiplicity from light and heavy fragments. The results were compared with previous evaluations. (authors)

2008-07-01

46

Studies of L x-rays from 64 MeV iodine projectiles in collision with gas targets  

International Nuclear Information System (INIS)

We have studied L x-rays from 64 MeV iodine projectile in collision with various gas targets, Z_2 #18, do not arise from selective M subshell vacancy population, has been conclusively established by the observations by Datz et al (1971) and by Saha et al (1996) that the measured intensity ratio of the Ll and L#alpha# lines, which arise because of transitions from different M subshells into the same L, subshell, does not show any periodic behaviour with Z, but stays rather constant. Differences in the measured L#beta#_1/L#alpha# intensity ratio of iodine with 7"+ and 24"+ charge states impinging on Kr target established the minor role of the electrons in the N shell of the projectile in the x-ray production mechanism. (author)

1997-11-17

47

Semiclassical calculation of photon-stimulated Schwinger pair creation  

International Nuclear Information System (INIS)

We consider the electron-positron pair creation by a photon in an external constant electric field. The presented treatment is based on a purely quasiclassical calculation of the imaginary part of the on-shell photon polarization operator. By using this approach we find the pair production rate for photons with polarization parallel as well as orthogonal to the external electric field in the leading order in the parameter eE/m"2, which has been recently found by other methods. For the orthogonal polarization we also find a new contribution to the rate, which is leading in the ratio of the photon energy to the electron mass #omega#/m. We also reproduce by a purely geometrical calculation the exponential factor in the probability of the stimulated pair creation at arbitrary energy of the photon.

2010-04-15

48

Influence of sulfur dioxide content of 20% and 92% sulfuric acid on anodic behavior of stainless steels  

Energy Technology Data Exchange (ETDEWEB)

This paper investigates steels 12Kh18N10T, 10Kh17N13M2T, 08Kh22N6T, and 08Kh21N6M2T. In corrosion of stainless steels in sulfuric acid solutions, dissolved sulfur dioxide acts as a cathodic depolarizer, capable of being reduced to elemental sulfur or forming sulfides with the metal. Depending on the conditions, this is associated with some increase in potential and greater or lesser increase in corrosion or facilitation of passivation of active steel. After passivation the influence of SO/sub 2/ is negligible. The results of this investigation were used as initial data for developing systems of anodic protection for shell-and-tube heat exchangers for sulfuric acid.

1986-07-01

49

A first principles study on optical transparency mechanism in Dy doped #alpha#-SiAlON ceramics  

International Nuclear Information System (INIS)

Dy doped #alpha#-SiAlON ceramics prepared by the hot-pressing method show a high optical transmittance value, >70%, in the infrared region of 1.5-4.5 #mu#m. First principles calculations have been carried out to reveal the underlying transparency mechanism. It is found that the valence shell of doped Dy atoms interacts strongly with the doping states of #alpha#-SiAlON, resulting in the increase in the optical gap from 0.4 to 1.1 eV, which suppresses the photoabsorption in the wavelength region longer than 1.0 #mu#m and leads to the good transparency property. The calculated optical transmission spectra are in good agreement with the corresponding experiments.

2009-11-01

50

HST/ACS observations of shell galaxies: inner shells, shell colours and dust  

CERN Document Server

AIM:Learn more about the origin of shells and dust in early type galaxies. METHOD: V-I colours of shells and underlying galaxies are derived, using HST Advanced Camera for Surveys (ACS) data. A galaxy model is made locally in wedges and subtracted to determine shell profiles and colours. We applied Voronoi binning to our data to get smoothed colour maps of the galaxies. Comparison with N-body simulations from the literature gives more insight to the origin of the shell features. Shell positions and dust characteristics are inferred from model galaxy subtracted images. RESULT: The ACS images reveal shells well within the effective radius in some galaxies (at 1.7 kpc in the case of NGC 5982). In some cases, strong nuclear dust patches prevent detection of inner shells. Most shells have colours which are similar to the ...

2007-01-01

51

Core-shell polymer nanorods by a two-step template wetting process  

International Nuclear Information System (INIS)

One-dimensional core-shell polymer nanowires offer many advantages and great potential for many different applications. In this paper we introduce a highly versatile two-step template wetting process to fabricate two-component core-shell polymer nanowires with controllable shell thickness. PLLA and PMMA were chosen as model polymers to demonstrate the feasibility of this process. Solution wetting with different concentrations of polymer solutions was used to fabricate the shell layer and melt wetting was used to fill the shell with the core polymer. The shell thickness was analyzed as a function of the polymer solution concentration and viscosity, and the core-shell morphology was observed with TEM. This paper demonstrates the feasibility of fabricating polymer core-shell nanostructures using our two-step template ...

2009-07-22

52

The jet-powered optical nebula of Cygnus X-1  

CERN Document Server

We present H-alpha and [O III] (5007 Angstroms) images of the nebula powered by the jet of the black hole candidate and microquasar Cygnus X-1, observed with the 2.5m Isaac Newton Telescope (INT). The ring-like structure is luminous in [O III] and there exists a thin outer shell with a high [O III] / H-alpha flux ratio. This outer shell probably originates in the collisionally excited atoms close to the front of the bow shock. Its presence indicates that the gas is shock excited as opposed to photoionised, supporting the jet-powered scenario. The shock velocity was previously constrained at 20 = 100 km/s (1 sigma confidence) based on a comparison of the observed [O III] / H-alpha ratio in the bow shock with a number of radiative shock models. From this we further constrain the time-averaged power of the jet: P_Jet = (4 - 14)*10^36 erg/s. The H-alpha flux behind the shock front is typically 4*10^-15 erg/s/cm^2/arcsec^2, and ...

2007-01-01

53

Electron impact excitation cross sections in F-like selenium  

Science.gov (United States)

Cross sections for excitation induced by electron collision between low-lying 1s{sup 2}2s{sup 2}2p{sup 5} and 1s{sup 2}2s2p{sup 6} states of f-like selenium and from these states to singly excited states with the excited electron occupying the M shell have been calculated by relativistic distorted-wave Born procedures. The GRASP{sup 2} code was used for the atomic structure calculations. The continuum orbitals for the construction of continuum states were computed in the distorted-wave approximation, in which the distorted-wave potential used was the spherically averaged potential of the nucleus plus the potential of the bound electrons of the bound state. The cross sections for excitations were computed first by a 233-level multiconfiguration Dirac-Fock (MCDF) configuration expansion and then by a 279-level MCDF configuration expansion. The latter procedure, which also took into account contributions from all the participating singly excited ...

1998-09-01

54

Direct chemical information from special radiotracers as well as from outer X-ray excitation  

Energy Technology Data Exchange (ETDEWEB)

Radionuclides exhibiting in decaying a strong interaction between nucleus and electron shell (especially electron capture and internal conversion) are, in principle, sensitive to their chemical surroundings. Consequently, they can be used to yield chemical information after an appropriate labelling procedure. The information can be extracted from the decay rate variation as well as from their X-ray emission as a response to an inner-shell vacancy creation during nuclear deexcitation. As an example of the former method the relationship between the decay rate of /sup 99m/Tc and the chemical structures of pertechnetate and bis(meso-dimercapto-succinate)oxotechnetate(V) is considered. Lower expectations with respect to measuring techniques are associated with the observation of X-ray emission. For a number of elements (especially 3d transition elements) the K/sub ..cap alpha..//K/sub ..beta../ X-ray intensity ratio was found to ...

1983-09-01

55

Direct chemical information from special radiotracers as well as from outer X-ray excitation  

International Nuclear Information System (INIS)

Radionuclides exhibiting in decaying a strong interaction between nucleus and electron shell (especially electron capture and internal conversion) are, in principle, sensitive to their chemical surroundings. Consequently, they can be used to yield chemical information after an appropriate labelling procedure. The information can be extracted from the decay rate variation as well as from their X-ray emission as a response to an inner-shell vacancy creation during nuclear deexcitation. As an example of the former method the relationship between the decay rate of /sup 99m/Tc and the chemical structures of pertechnetate and bis(meso-dimercapto-succinate)oxotechnetate(V) is considered. Lower expectations with respect to measuring techniques are associated with the observation of X-ray emission. For a number of elements (especially 3d transition elements) the K/sub #alpha#//K/sub #betta#/ X-ray intensity ratio was found to be an ...

1982-10-01

56

Alloying effect on K to L shell vacancy transfer probabilities in 3d transition metals  

British Library Electronic Table of Contents (United Kingdom)

The alloying effects on K to L shell vacancy transfer probabilities (?KL) in 3d transition metals have been carried out by X-ray fluorescence studies of various alloy compositions. K X-ray intensity ratios of Ti, Cr, Fe, Co, Ni, and Cu elements in the FexNi1?x, FexCr1?x, NixCr1?x, FexCryNi1?(x+y), TixNi1?x, TixCo1?x, and CoxCu1?x alloys have been measured following excitation by 22.69keV X-rays from a 10 mCi 109Cd radioactive point source and ?KL values for alloying elements have been determined from these ratios. The spectrum of characteristic K-X-ray photons from samples were detected with a high resolution Si(Li) detector coupled to a 4 K multichannel analyzer. The present investigation makes it possible to ...

2010-01-01

57

3D transient calculations of PGV-1000 based on TRAC  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: During calculations of SAR accidents and transients it is necessary to perform steam generator simulation. Best accuracy is 3D transient calculations presented in report. Main outcomes of work was next: 1. There was shown by analysis the applicability of code TRAC (Los-Alamos laboratory) for thermal - hydraulic calculations of horizontal steam generator PGV-1000M. Special nodalization scheme was developed for it purposes. 2. Validation and selection of thermal-hydraulic correlations for improvement of using the code at calculation PGV-1000M were performed. As result Labuntsov formula is recommended for horizontal SG. 3. Calculations of nominal mode operation of PGV-1000M for cross-verification with code STEG (Electrogorsk Research and Engineering Center EREC) during its verification were performed. Solution by TRAC was obtained for transient problem after stabilization time. 4. Development ...

2005-07-01

58

Heating and ventilation concept for a better room climate and for energy conservation. Part 1; Heiz- und Lueftungskonzept fuer besseres Raumklima und Energieeinsparung. T. 1  

Energy Technology Data Exchange (ETDEWEB)

Ventilation, cooling and illumination of modern high-rise office buildings with high-quality thermal insulation (average k-value 1.0 W/m12K) and high loads from office machinery (up to 20 W/m12 and beyond) are problematic even for modern facility management systems, with consequences for the building shell, heating system, and window ventilation. [Deutsch] Die Lueftung, Kuehlung und Beleuchtung moderner Buerohochbauten mit extremer Waermedaemmung (mittlerer K-Wert 1,0 W/m{sup 2}K) und hohen Bueromaschinenlasten (bis zu 20 W/m{sup 2} und mehr) verursachen auch heute noch erhebliche Probleme, obwohl die technische Gebaeudeausruestung weiterentwickelt wurde. Dies zeigt sich vor allem bei der Fassadenausbildung der Heizung und Fensterlueftung. (orig.)

1999-11-01

59

3-D modelling the electric field due to ocean tidal flow and comparison with observations  

DEFF Research Database (Denmark)

The tidal motion of the ocean water through the ambient magnetic field, generates secondary electric field. This motionally induced electric field can be detected in the sea or inland and has a potential for electrical soundings of the Earth. A first goal of the paper is to gain an understanding of the global distribution of the electric signal due to tidal ocean flow. We simulate the electric signals for two tidal constituents - lunar semidiurnal (M2) and diurnal (O1) tides. We assume a realistic Earth's conductivity model with a surface thin shell and 1-D mantle underneath. Simulations demonstrate that in some coastal regions the amplitudes of the electric field can reach 100 mV/km and 10 mV/km for M2 and O1 tides respectively. The changes of lithosphere resistance produce detectable changes in the tidal electric signals. We show that our predictions are in a good agreement with ...

2006-01-01

60

Initial post-buckling behavior of cylindrical shells under external pressure.  

Science.gov (United States)

Circular cylindrical shells with support subjected to lateral or hydrostatic pressure, using Koiter postbuckling theory

1968-01-01

61

Jet flow analysis of liquid poison injection in a CANDU reactor using source term  

Energy Technology Data Exchange (ETDEWEB)

For the performance analysis of Canadian deuterium uranium (CANDU) reactor shutdown system number 2 (SDS2), a computational fluid dynamics model of poison jet flow has been developed to estimate the flow field and poison concentration formed inside the CANDU reactor calandria. As the ratio of calandria shell radius over injection nozzle hole diameter is so large (1055), it is impractical to develop a full-size model encompassing the whole calandria shell. In order to reduce the model to a manageable size, a quarter of one-pitch length segment of the shell was modeled using symmetric nature of the jet; and the injected jet was treated as a source term to avoid the modeling difficulty caused by the big difference of the hole sizes. For the analysis of an actual CANDU-6 SDS2 poison injection, the grid structure was determined based on the results of two-dimensional real- and source-jet simulations. The maximum injection ...

2001-01-01

62

Rotational structures in {sup 177}Ta  

Energy Technology Data Exchange (ETDEWEB)

High-spin states in {sup 177}Ta were produced using the {sup 170}Er({sup 11}B, 4{ital n}) reaction at 55 and 60 MeV. Considerable extensions have been made to the previously known level scheme, and new structures have been found. {ital B}({ital M}1)/{ital B}({ital E}2) ratios have been extracted for strongly coupled bands. The behavior of the different rotational cascades, in particular the anomalous crossing frequency observed in the [541]1/2{sup {minus}} proton {ital h}{sub 9/2} band and the occurrence of ``identical bands,`` is discussed. Comparisons are made with projected shell model calculations.

1995-09-01

63

Rotational structures in "1"7"7Ta  

International Nuclear Information System (INIS)

High-spin states in "1"7"7Ta were produced using the "1"7"0Er("1"1B, 4n) reaction at 55 and 60 MeV. Considerable extensions have been made to the previously known level scheme, and new structures have been found. B(M1)/B(E2) ratios have been extracted for strongly coupled bands. The behavior of the different rotational cascades, in particular the anomalous crossing frequency observed in the [541]1/2"- proton h_9_/_2 band and the occurrence of ''identical bands,'' is discussed. Comparisons are made with projected shell model calculations.

64

Cancer-cell-specific cytotoxicity of non-oxidized iron elements in iron core-gold shell NPs  

British Library Electronic Table of Contents (United Kingdom)

Gold-coated iron nanoparticles (NPs) selectively and significantly (P <0.0001) inhibit proliferation of oral- and colorectal-cancer cells in vitro at doses as low as 5 mg/mL, but have little adverse effect on normal healthy control cells. The particle treatment caused delay in cell-cycle progression, especially in the S-phase. There was no significant difference in the NP uptake between cancer and control cells, and cytotoxicity resulted primarily from the iron core, before oxidation, rather than from the Fe ions released from the core. In contrast with magnetic NPs that usually serve as drug carriers, diagnostic probes or hyperthermia media, the iron, before oxidation, in the NPs selectively suppressed cancer cell growth and left healthy control cells unaffected in vitro and in vivo. This...

2011-01-01

65

Strength functions of primary transitions following thermal neutron capture in strontium  

Energy Technology Data Exchange (ETDEWEB)

The primary E1, M1 and E2 ..gamma..-radiation in /sup 87,88,89/Sr observed after thermal neutron capture was compared with the predictions of single particle and giant resonance models. The nuclei feature a wide range of neutron binding energies between 6.3 and 11.1 MeV, which makes a 5.5 MeV spectrum of primary transition energies available for investigation. The (n, ..gamma..) reaction was used to estimate the parameters of the spin-flip M1 giant resonance in strontium. The total energy weighted M1 strength of this resonance exceeds the results of shell model and random phase approximation calculations for /sup 90/Zr by a factor of 3-4. The E1 strengths were found to agree with the established giant dipole resonance model. The few data on primary E2 transitions do not allow to differentiate between the giant quadrupole resonance and the single particle models.

1989-04-01

66

Strength functions of primary transitions following thermal neutron capture in strontium  

International Nuclear Information System (INIS)

The primary E1, M1 and E2 #gamma#-radiation in "8"7","8"8","8"9Sr observed after thermal neutron capture was compared with the predictions of single particle and giant resonance models. The nuclei feature a wide range of neutron binding energies between 6.3 and 11.1 MeV, which makes a 5.5 MeV spectrum of primary transition energies available for investigation. The (n, #gamma#) reaction was used to estimate the parameters of the spin-flip M1 giant resonance in strontium. The total energy weighted M1 strength of this resonance exceeds the results of shell model and random phase approximation calculations for "9"0Zr by a factor of 3-4. The E1 strengths were found to agree with the established giant dipole resonance model. The few data on primary E2 transitions do not allow to differentiate between the giant quadrupole resonance and the single particle models. (orig.).

67

Production of wood plastic properties using gamma radiation as a polimerization agent  

International Nuclear Information System (INIS)

The properties of wood plastic composites (WPC) based on Pinus Radiata D. Don impregnated with methylmethacrylate and subsequently polymerized with gamma radiation were studied. Different systems of impregnation were utilized, in order to obtain partial and shell loads. The minimum irradiation dose uses was 16 kGy. The following tests were made to the material: static bending, compression strenght parallel to grain, hardness, sheer strength, toughness, water absorption, dimensional stability and flame propagation index. To evaluate the testing, the results of the samples were separated according final density in the ranges: R_1 = 429-483 kg/m3 (without treatment); R_2 = 500-650 kg/m3 and R3 = 651-850 kg/m3. In general, the best results were obtained for samples of high density. The most important results were achieved for dimensional stability, water absorption and hardness. (Author).

1984-01-01

68

Studies of off-shell amplitudes in string theory  

Energy Technology Data Exchange (ETDEWEB)

Off-shell amplitudes for the open bosonic string and the closed spinning string are considered. Due to the presence of corners on the open string world sheet, strict Weyl invariance is broken. A consistent gauge-fixing procedure to treat this anomaly is described. Factorization of amplitudes with one or two off-shell strings and any number of on-shell tachyons is established. An attempt is made to construct a propagator for the spinning string. The inherent ambiguities in the choice of boundary conditions for the fermionic coordinates are outlined.

1989-01-01

72

Energy-filtered electron microscopy for imaging core-shell nanostructures  

Energy Technology Data Exchange (ETDEWEB)

CuAg core-shell nanoparticles are synthesized by ultra-high vacuum thermal evaporation. We show on this system how the Energy-Filtered Transmission Electron Microscopy (EFTEM) technique allows one to improve the characterization by precisely pointing out the formation of core-shell arrangements in bimetallic nanoparticle assemblies. A criterion to measure the shell thickness from EFTEM images on unique core-shell nanoparticles is defined, that can be used for core-shell nanoparticles of any sizes, with shell thicknesses over 1 nm. It is based on the intensity variation along a line drawn across a core-shell nanoparticle on a EFTEM image. This criterion has been validated by a close comparison of the shell thickness measurements performed in this work and the ones obtained by acoustic micro-Raman spectroscopy. Using this ...

2008-08-15

73

Off-shell amplitudes for open bosonic strings  

Energy Technology Data Exchange (ETDEWEB)

An extension of the Polyakov path-integral formulation to compute off-shell amplitudes for open bosonic strings is derived. Boundary conditions require evaluating the path integral on open surfaces with corners on the boundaries. The contribution to the topological term in the action from the corners is exactly that required for unitarity. The presence of corners introduces a Weyl anomaly in the Polyakov measure. This requires a gauge-fixing procedure for the off-shell amplitudes. Consistent factorization of amplitudes with one or two off-shell strings and any number of on-shell tachyons is established.

1988-02-15

74

Evolution of a vacuum shell in the Friedmann-Schwarzschild world  

International Nuclear Information System (INIS)

The method of an effective potential is used to investigate the possible types of evolution of vacuum shells in the Friedmann-Schwarzschild world. Such shells are assumed to emerge during phase transitions in the early Universe. The possible global geometries are constructed for the Friedmann-Schwarzschild worlds. Approximate solutions to the equation of motion of a vacuum shell have been found. The conditions under which the end result of the evolution of the vacuum shells under consideration is the formation of black holes and wormholes with baby universes inside have been found. The interior of this world can be a closed, flat, or open Friedmann universe.

2008-08-01

75

Mass and charge distributions in the very asymmetric thermal neutron induced fission of the odd-Z nucleus {sup 242m}Am  

Energy Technology Data Exchange (ETDEWEB)

Yields of light fission products (A = 68, 70-84, 87, 88, 94, 96, 98, 102 and 106-108), their kinetic energies and nuclear charge distributions (A 71-84, 87 and 88) in the thermal neutron induced fission of the odd-Z nucleus {sup 242m}Am(Z = 95) were measured using the mass-separator Lohengrin at the Institute Laue-Langevin in Grenoble (France). The mass yield curve shows a fine structure at A = 70, probably due to shell and/or odd-even effects affecting also the nuclear charge distribution. The analysis of isotopic chain yields gives evidence for a very low excitation energy of the lightest fission fragments observed. A preferential formation of fragments with even Z is found for this odd-Z compound nucleus. Calculated values for the local odd-even effect are comparable with those for the neighbouring even-Z fissile nuclides and increase from 13% to 30% with increasing asymmetry of the mass split (A{sub L} = 84 to 68 and Z{sub L} = 35 to 28). ...

1999-10-25

76

Development of technology to utilize existing tobacco kilns and/or tobacco storage barns for curing (drying) and/or storage of other crops  

Energy Technology Data Exchange (ETDEWEB)

This report investigates methods to utilize existing bulk tobacco kilns for curing (drying) of shelled corn, peanuts, and baled hay. In recent years Ontario tobacco producers have had to reduce production levels due to a declining demand for flue-cured tobacco. Many tobacco producers are currently diversifying into other crops. Some of these crops require curing and/or storage. Because of high capital costs to purchase conventional curing and/or storage facilities, tobacco producers wish to reduce their initial diversification costs by modifying their existing tobacco kilns (tobacco drying structures) and/or tobacco storage barns for this purpose. The investigation included high profile and low profile downdraft stick kilns, bulk kilns, and tobacco storage (pack) barns. Corn, peanuts, and hay were considered in relation to bulk kiln specifications and modifications, handling, drying and storage methods, energy requirements, cost, and quality of end product. The ...

1988-01-01

77

The scattering amplitude for four off-shell tachyons from functional integrals  

International Nuclear Information System (INIS)

We use functional integral techniques to calculate the scattering amplitude for four open off-shell tachyons in Witten's string field theory and show that the residues of the first three poles agree with those obtained using oscillator methods. (orig.).

78

Synthesis and characterization of thermoresponsive polyamidoamine-polyethylene glycol-poly (D, L-lactide) (PAMAM-PEG-PDLLA) core-shell nanoparticles  

UK PubMed Central (United Kingdom)

This work describes the synthesis and characterization of novel thermoresponsive highly-branched polyamidoamine-polyethylene glycol-poly (D, L-lactide) (PAMAM-PEG-PDLLA) core-shell nanoparticles....Full Text Available

2010-03-01

79

Scattering amplitude for four off-shell tachyons from functional integrals  

Energy Technology Data Exchange (ETDEWEB)

We use functional integral techniques to calculate the scattering amplitude for four open off-shell tachyons in Witten's string field theory and show that the residues of the first three poles agree with those obtained using oscillator methods.

1988-05-30

80

On the probability of flucton production in the 1p-shell nuclei  

International Nuclear Information System (INIS)

Probabilities of flucton production have been calculated for the 1p-shell nuclei and its modification by the Yastrov method. The results obtained are in a qualitative agreement with the data resulting from the analysis of experiment in an assumption of a flucton mechanism of proton-nuclear inclusive reactions with the production of cumulative particles.

81

Climate Change, Genetics or Human Choice: Why Were the Shells of Mankind's Earliest Ornament Larger in the Pleistocene Than in the Holocene?  

UK PubMed Central (United Kingdom)

BackgroundThe southern African tick shell, Nassarius kraussianus (Dunker, 1846), has been identified as being the earliest known ornamental object used by human...Full Text Available

83

Cascade of Random Rotation and Scaling in a Shell Model Intermittent Turbulence  

International Nuclear Information System (INIS)

The time behaviors of intermittent turbulence in Gledzer-Ohkitani-Yamada model are investigated. Two kinds of orbits of each shell which is in the inertial range are discussed by portrait analysis in phase space. We find intermittent orbit parts wandering randomly and the directions of unstable quasi-periodic orbit parts of different shells form rotational, reversal and locked cascade of period three with shell number. We calculate the critical scaling of intermittent turbulence and the extended self-similarity of the two parts of orbit and point out that nonlinear scaling in inertial-range is decided by intermittent orbit parts.

2006-12-15

84

Sum rules for the inclusive. mu. -e conversion exotic reaction  

Energy Technology Data Exchange (ETDEWEB)

Microscopic non-energy weighted sum-rules for the total rates of the neutrinoless ..mu..-e conversion process are constructed in the frame of the shell model for closed shell nuclei. For non-closed shell nuclei the relevant rates were obtained by interpolation. Also the contribution of the coherent process to the total ..mu..-e conversion rate is calculated and discussed.

1989-01-19

85

Energy spectra and electromagnetic properties in lithium isotopes  

International Nuclear Information System (INIS)

Li shell-model calculation has been made in the isospin formalism in the complete (0 + n)#Planck constant##omega# model space with the assumption of a closed core "4He. The calculation could probably be improved by use of a better effective interaction and increasing shell model space. With the use of faster computer with large memories, the authors are in hope of calculation in spsd shell-model space

86

Visualization of direct contact heat transfer between water and molten alloy  

Energy Technology Data Exchange (ETDEWEB)

We have been developing an innovative Steam Generator concept of Fast Breeder Reactors by using liquid-liquid direct contact heat transfer. In this concept, the SG shell is filled with a molten alloys, which is heated by primary sodium. Water is fed into the high temperature molten alloy, and evaporates by direct contact heating. In order to obtain the fundamental information to discuss the heat transfer mechanisms of the direct contact between the water and the alloy, this phenomenon was visualized by real-time neutron radiography. JRR-3M real-time thermal neutron radiography in Japan Atomic Energy Research Institute was used. Followings are main results. (1) The vigorous evaporation occurs in the molten alloy. This phenomena is different from the known phenomenon such as the evaporation of refrigerant R-113 in the water. (2) The evaporation in the bubble has finished in a moment due to high heat transfer performance between the liquid and ...

1996-06-01

87

Synthesis and photo-degradation application of WO3/TiO2 hollow spheres  

British Library Electronic Table of Contents (United Kingdom)

A WO3/TiO2 composite, hollow-sphere photocatalyst with average diameter of 320nm and shell thickness of 50nm was successfully prepared using a template method. UV-vis diffuse reflectance spectra illustrated that the main absorption edges of the WO3/TiO2 hollow spheres were red-shifted compared to the TiO2 hollow spheres, indicating an extension of light absorption into the visible region of the composite photocatalyst. The WO3 and TiO2 phases were confirmed by X-ray diffraction analysis. BET isotherms revealed that the specific surface area and average pore diameter of the hollow spheres were 40.95m^2/g and 19nm, respectively. Photocatalytic experiments indicate that 78% MB was degraded by WO3/TiO2 hollow spheres under visible light within 80min. Under the same conditions, only 24% MB can ...

2011-01-01

88

Spherical nanostructured Si/C composite prepared by spray drying technique for lithium ion batteries anode  

International Nuclear Information System (INIS)

Spherical nanostructured Si/C composite was prepared by spray drying technique, followed by heat treatment, in which nanosized silicon and fine graphite particles were homogeneously embedded in carbon matrix pyrolyzed by phenol formaldehyde resin. Cyclic voltammetry tests showed two pairs of redox peaks corresponding to lithiation and delithiation of Si/C composite. The Si/C composite exhibited a reversible capacity of 635 mAh g"-"1 and good cycle performance used in lithium ion batteries. To improve cycle performance of this Si/C composite further, the carbon-coated Si/C composite was synthesized by the second spray drying and heat treatment processing. The cycle performance of carbon-coated Si/C composite was improved significantly, which was attributed to the formation of stable SEI passivation layers on the outer surface of carbon shell which protected the bared silicon from exposing to electrolyte directly.

2006-07-15

89

Results of 3-dimensional structural FE-modeling of the coil end-regions of the LHC main dipoles  

CERN Document Server

The transition region between the straight part and the ends of the coils of the LHC model and prototype dipole magnets are often identified as the origin of training quenches. In order to study how the discontinuities in the material properties of these regions affect coil pre-stress and possibly gain more insight in the quench behavior, a program was set up at CERN to analyze by 3D-FEM these particular regions. The ACCEL team, who performed a similar analysis for the main quadrupoles of the Superconducting Supercollider SSC, is entrusted with this program. In this paper we report on the results of 3D-modeling and analysis of the coil return end region, including the complete coil mass, of a 1-m single bore model magnet. This magnet represents all relevant features of the "two-in-one" LHC main dipole design concerning the winding configuration, the collar pack, the yoke, and the outer shell representing the He-vessel. The transition region ...

2000-01-01

90

Preparation, photocatalytic activities, and dye-sensitized solar-cell performance of submicron-scale TiO2 hollow spheres.  

Science.gov (United States)

We prepared submicron-scale spherical hollow particles of anatase TiO2 by using a polystyrene-bead template. The obtained particles were very uniform in size, with a diameter of 490 nm and a shell thickness of 30 nm. The Brunauer-Emmett-Teller surface area measurements revealed a large value of 70 m2/g. The photocatalytic property was investigated by the complete decomposition of gaseous isopropyl alcohol under UV irradiation. It was indicated that the activity of the hollow spheres was 1.8 times higher than that of the conventional P25 TiO2 nanoparticles with a diameter of 30 nm. Furthermore, we fabricated a dye-sensitized solar cell (DSC) using an electrode of the TiO2 hollow spheres, and examined the photovoltaic performance under simulated sunlight. Although the per-area efficiency was rather low (1.26%) because of a low area density of TiO2 on the electrode, the per-weight efficiency was 2.5 times higher than those of the conventional DSCs ...

2007-12-19

91

Experimental Electron Heat Diffusion in TJ-II ECRH Plasmas  

Energy Technology Data Exchange (ETDEWEB)

Interpretative transport has been used to revisit the global scalings of TJ-II ECRH plasmas from a local perspective. Density, rotational transform and ERCH power scans were analysed based upon Thomson Scattering data (electron density and temperature) in steady state discharges. A simple formula to obtain the thermal conductivity, assuming pure diffusion and negligible convective heat fluxes was used in a set of 161 discharges. All the analysis was performed with the ASTRA transport shell. The density scan indicates that inside n=0,4 there is no significant change of e with density in the range studied (0.4 <ne>(1019m-3) 1.0), while in 0,5 <0,8 approximately, e decreases with density. In the rotational transform scan it is found that the values of e when a low order rational of the rotational transform is present locally seem to be smaller for the corresponding range, although it is apparent a general beneficial effect of ...

2006-07-01

92

Biological in situ remediation of a former pond for trickling waste water containing explosives  

Energy Technology Data Exchange (ETDEWEB)

WASAG DECON developed a concept for the biological in situ remediation of an TNT-contaminated former seepage pond. This pond is located on the site of an ammunition factory in Lower Saxony. Unit 1982 all the waste water from the production buildings was directed into this pond, including TNT-contaminated water from the flushing of shells. Due to this practice, the sediment of the pond, the underlying soil and the groundwater became contaminated with TNT. The area of the soil contamination adds to abut 2.000 m{sup 2}. The remediation concept includes three steps: 1. Excavation of the most highly contaminated soil with TNT-concentrations above 1000 mg/kg. 2. Reduction of the remaining contamination by a biological in situ treatment using organic and inorganic amendments and mechanical tillage. After about to years of treatment, remediation goals of 50 mg/kg are expected to be reached on most of the area. 3. Contaminations eventually remaining in ...

2003-07-01

93

Average neutron resonance parameters and radiative capture cross sections for the isotopes of molybdenum  

International Nuclear Information System (INIS)

The neutron capture cross sections of the stable molybdenum isotopes have been measured with high energy resolution (#DELTA#E/E < approximately 0.2%), between 3 and 90 keV neutron energy, at the 40 m station of ORELA. Average resonance parameters are extracted for s- and p-wave resonances. The s-wave neutron strength function is close to 0.5x10"-"4 for all isotopes, but the p-wave strength function exhibits a well defined peak near A approximately 95. Both s- and p-wave radiative widths decrease markedly as further neutrons are added to the closed shell. The p-wave radiative widths are generally greater than the s-wave widths showing the presence of non-statistical #gamma#-decay mechanisms. Valence neutron theory fails to explain the magnitude of the p- to s-wave radiative width disparity and doorway state processes are invoked. In particular, the data for "9"8Mo appear to violate the usual valence theory, since the correlations between ...

94

Advanced direct liquefaction concepts for PETC generic units. Quarterly report, October 1991--December 1991  

Science.gov (United States)

A laser pyrolysis technique has been used to produce ultrafine particles of iron carbide with diameters ranging from 2 to 20 nm. Catalysis using iron carbide was investigated in the liquefaction of Wyodak subbituminous coal; yields were determined. A study was carried out to examine the possibility of using an ultrasonic extraction technique as a rapid method of product work-up of samples following pretreatment or liquefaction experiments. A similar study had shown that extraction of coal-derived products by an ultrasonic method was rapid and gave yields and product distributions comparable to those obtained by Soxhlet extraction. On another project, three different types of supported catalysts were used to test activity for the combined water-gas shift hydrogenation of a synthetic donor solvent. The three catalysts tested were: (1) Alumina supported NiMo catalyst-Shell 324m; (2) Bulk hydrous TiO NiMo catalyst; (3) Thin film hydrous TiO ...

1991-12-31

95

Use of shell model calculations in R-matrix studies of neutron-induced reactions  

Energy Technology Data Exchange (ETDEWEB)

R-matrix analyses of neutron-induced reactions for many of the lightest p-shell nuclei are difficult due to a lack of distinct resonance structure in the reaction cross sections. Initial values for the required R-matrix parameters, E,sub(lambda) and ..gamma..sub(lambdac) for states in the compound system, can be obtained from shell model calculations. In the present work, the results of recent shell model calculations for the lithium isotopes have been used in R-matrix analyses of /sup 6/Li+n and /sup 7/Li+n reactions for E sub(n) < 8 MeV. Consequences of the shell model predictions for the level structure of /sup 7/Li and /sup 8/Li on the /sup 6/Li+n and /sup 7/Li+n reaction mechanisms and cross sections are discussed.

1986-01-01

96

Nomographs for the evaluation of the theoretical wall-thickness of cylinder shells without cutouts and branches and cylinder shells with an inclined single branch without additional thickening according to TRD 300/301 (loading condition: predominantly static internal compressive load)  

Energy Technology Data Exchange (ETDEWEB)

The evaluation of calculated values determined by means of the equations given in the TRD 300/301 standard resulted in two nomographs by which it is possible to find the theoretical wall thickness of cylinder shells without cutouts and branches as well as cylinder shells with an inclined or vertical single branch without additional thickening. The equations for the calculation of cylinder shells with an inclined single branch according to TRD 301 having only an iterative solution, the nomographs will be a considerable help for the engineering work. The determination of the theoretical wall-thickness from the nomographs is demonstrated by means of examples.

1981-06-01

97

Thermomechanical vibration analysis of a functionally graded shell with flowing fluid  

Energy Technology Data Exchange (ETDEWEB)

This paper reports the results of an investigation into the vibration of functionally graded cylindrical shells with flowing fluid, embedded in an elastic medium, under mechanical and thermal loads. By considering rotary inertia, the first-order shear deformation theory (FSDT) and the fluid velocity potential, the dynamic equation of functionally graded cylindrical shells with flowing fluid is derived. Here, heat conduction equation along the thickness of the shell is applied to determine the temperature distribution and material properties are assumed to be graded distribution along the thickness direction according to a power-law in terms of the volume fractions of the constituents. The equations of eigenvalue problem are obtained by using a modal expansion method. In numerical examples, effects of material composition, thermal loading, static axial loading, flow velocity, medium stiffness and shell ...

2008-11-15

98

Two-proton excitations at the Z=38 and Z=40 sub-shell closures  

International Nuclear Information System (INIS)

The "8"6Kr("3He,n)"8"8Sr and "8"8Sr("3He,n)"9"0Zr reactions were studied to determine whether significant excited 0"+ strength was observed or whether these nuclei exhibited absence of excited state strength generally seen away from shell closures. Various properties of the levels are considered including angular distributions, spins, parities, interference, and enhancement. It is concluded that neither "8"8Sr nor "9"0Zr exhibit the strong proton pairing vibration expected for a closed proton shell nucleus.

1977-11-01

99

Shell effects in the symmetric-modal fission of pre-actinide nuclei  

International Nuclear Information System (INIS)

Mass distributions of fragments in the low-energy fission of nuclei from "1"8"7Ir to "2"1"3At have been analysed. This analysis has shown that shell effects in symmetric-mode fragment mass yields from the fission of pre-actinide nuclei could be described if one assumes the existence of two strongly deformed neutron shells in the arising fragments with neutron numbers N_1#approx#52 and N_2#approx#68. A new method has been proposed for quantitatively describing the mass distributions of the symmetric fission mode for pre-actinides with A#approx#180-220. (orig.)

1998-09-21

100

x - NASA Technical Reports Server  

Science.gov (United States)

Mar 1, 2011 ... Initial post-buckling behavior of cylindrical shells under external pressure. Author: Amazigo, J. C.; Budianski, B. ...

102

REVIEW OF EXPLOSIVE (CHEMICAL) FORMING  

Science.gov (United States)

... explosive (shotgun shells, etc.) method of forming is being replaced--for the most part--by the electri- cal discharge and magnetic forming methods. ...

1965-04-01

105

Closed-string tachyon condensation and the on-shell effective action of open-string tachyons  

Energy Technology Data Exchange (ETDEWEB)

We study how the effect of closed-string tachyon condensation can enter into the on-shell effective action of open-string tachyons in the bosonic case. We also consider open-string one-loop quantum corrections to the on-shell action. We use a sigma-model approach with boundary terms, and we utilize some results of boundary string field theory (BSFT) to define the on-shell effective action. We regard D-instanton-like objects with appropriate weight as closed-string tachyon tadpoles, and we insert them into worldsheets to analyze the effect of closed-string tachyons. (author)

2001-11-01

106

Acoustic resonances in two-dimensional radial sonic crystal shells  

Energy Technology Data Exchange (ETDEWEB)

Radial sonic crystals (RSC) are fluidlike structures infinitely periodic along the radial direction that verify the Bloch theorem and are possible only if certain specially designed acoustic metamaterials with mass density anisotropy can be engineered (see Torrent and Sanchez-Dehesa 2009 Phys. Rev. Lett. 103 064301). A comprehensive analysis of two-dimensional (2D) RSC shells is reported here. A given shell is in fact a circular slab with a central cavity. These finite crystal structures contain Fabry-Perot-like resonances and modes strongly localized at the central cavity. Semi-analytical expressions are developed to obtain the quality factors of the different resonances, their symmetry features and their excitation properties. The results reported here are completely general and can be extended to equivalent 3D spherical shells and to their photonic counterparts.

2010-07-15

107

Solvent effects on the solvation shell exchange kinetics  

Energy Technology Data Exchange (ETDEWEB)

Classical molecular dynamics simulations are carried out to investigate the salvation shell exchange kinetics of potassium ion in bulk water, chloroform, and carbon tetrachloride. The reactive flux method is used to compute the dissociation rates. The influence of the solvent on the reaction rates and kinetic properties of this exchange process will be discussed. Comparison will be also be made to the prediction of the Grote-Hynes theory.

1997-12-31

108

Redundancy of the off-shell parameters in chiral effective field theory with explicit spin-3/2 degrees of freedom  

Energy Technology Data Exchange (ETDEWEB)

In this note we prove to all orders in the small scale expansion that all off-shell parameters which appear in the chiral effective Lagrangian with explicit DELTA(1232) isobar degrees of freedom can be absorbed into redefinitions of certain low-energy constants and are therefore redundant.

2010-01-18

109

Pd-Na/F double exploding foil photoionization experiment  

Science.gov (United States)

The achievement of inner-shell photoionization of Zn-like Pd by means of two exploding foils is described. This resulted in the soft X-ray transition 3d94s2-3d104p at 46 A. It is shown that the photoionization of inner shell electrons in highly stripped ions can lead to X-ray transitions which may be candidates for X-ray lasers under 50 A.

1990-03-01

110

Partial preservation of the Tentaculites Crotalinus shell from Ponta Grossa Formation (Devonian)  

International Nuclear Information System (INIS)

This paper deals with an analysis of a single specimen of Tentaculites crotalinus SALTER emend. CIGUEL et al. (1984) that present a possible partial preservation of the shell. It comes from an outcrop of the Grossa Formation (Devonian) near Jaguariaiva, State of Parana. The skeletal microstructure of the Tentaculitoidea shell rather poorly Known. Thus, the phylogenetic relationships of these invertebrates still uncertain. Tentaculitids are very common fossils in Devonian Ponta Grossa Formation (Parana Basin) but so far Known only from external and internal moulds. The objective of this study is to demonstrate wheter the layer found in between the internal and external mould is or not a case shell preservation. The chemical composition of this layer and of the external mould was analysed by X rays. X rays difratometry was applied only to the matrix (at the external mould). The structure of the supposed ...

111

Load requirements for maintaining structural integrity of Hanford single-shell tanks during waste feed delivery and retrieval activities  

Energy Technology Data Exchange (ETDEWEB)

This document provides structural load requirements and their basis for maintaining the structural integrity of the Hanford Single-Shell Tanks during waste feed delivery and retrieval activities. The requirements are based on a review of previous requirements and their basis documents as well as load histories with particular emphasis on the proposed lead transfer feed tanks for the privatized vitrification plant.

1999-09-22

112

Closed-string tachyon condensation and loop corrected on-shell effective action of open-string tachyons  

International Nuclear Information System (INIS)

We propose a basic strategy to obtain a consistent on-shell effective action of open-string tachyons, on the background where closed-string tachyons are already condensed. We use sigma-model approach, basically. We regard D-instanton-like objects with appropriate weight as closed-string tachyon tadpoles, and we insert them into worldsheets to analyze the effect of closed-string tachyons.

2002-01-23

113

Characterization of the corrosion behavior of the carbon steel liner in Hanford Site single-shell tanks  

Energy Technology Data Exchange (ETDEWEB)

Six safety initiatives have been identified for accelerating the resolution of waste tank safety issues and closure of unreviewed safety questions. Safety Initiative 5 is to reduce safety and environmental risk from tank leaks. Item d of Safety Initiative 5 is to complete corrosion studies of single-shell tanks to determine failure mechanisms and corrosion control options to minimize further degradation by June 1994. This report has been prepared to fulfill Safety Initiative 5, Item d. The corrosion mechanisms that apply to Hanford Site single-shell tanks are stress corrosion cracking, pitting/crevice corrosion, uniform corrosion, hydrogen embrittlement, and microbiologically influenced corrosion. The corrosion data relevant to the single-shell tanks dates back three decades, when results were obtained from in-situ corrosion coupons in a few single-shell tanks. Since that time there have been intertank ...

1994-06-01

114

Structural acceptance criteria for the evaulation of existing double-shell waste storage tanks located at the Hanford site, Richland, Washington  

Energy Technology Data Exchange (ETDEWEB)

The structural acceptance criteria contained herein for the evaluation of existing underground double-shell waste storage tanks located at the Hanford Site is part of the Life Management/Aging Management Program of the Tank Waste Remediation System. The purpose of the overall life management program is to ensure that confinement of the waste is maintained over the required service life of the tanks. Characterization of the present condition of the tanks, understanding and characterization of potential degradation mechanisms, and development of tank structural acceptance criteria based on previous service and projected use are prerequisites to assessing tank integrity, to projecting the length of tank service, and to developing and applying prudent fixes or repairs. The criteria provided herein summarize the requirements for the analysis and structural qualification of the existing double-shell tanks for continued operation. Code reconciliation ...

1995-09-01

115

Elephant's foot phenomenon in liquid storage tanks  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a method for analyzing the seismic response of a flat bottomed cylindrical liquid storage tank to vertical earthquake excitation. Here, vertical earthquake acceleration is considered to correspond to an increase in the density of a stored liquid. Taking into account the vertical and horizontal earthquake loads, hydrostatic pressure, and considering restrictive moment and shear forces at shell-bottom welded joint, the author has calculated circumferential and longitudinal stresses. These are combined to more accurately approximate the stresses at the base shell course. The calculated result closely conforms to the actual damage, termed ''elephant's foot,'' observed in the fuel storage tanks damaged in the Tangshan earthquake. This result shows that the ''elephant's foot'' phenomenon is not caused by buckling of the tank ...

1983-01-01

116

Anti-cancer drug loaded iron-gold core-shell nanoparticles (Fe@Au) for magnetic drug targeting.  

Science.gov (United States)

Magnetic drug targeting, using core-shell magnetic carrier particles loaded with anti-cancer drugs, is an emerging and significant method of cancer treatment. Gold shell-iron core nanoparticles (Fe@Au) were synthesized by the reverse micelle method with aqueous reactants, surfactant, co-surfactant and oil phase. XRD, XPS, TEM and magnetic property measurements were utilized to characterize these core-shell nanoparticles. Magnetic measurements showed that the particles were superparamagnetic at room temperature and that the saturation magnetization decreased with increasing gold concentration. The anti-cancer drug doxorubicin (DOX) was loaded onto these Fe@Au nanoparticle carriers and the drug release profiles showed that upto 25% of adsorbed drug was released in 80 h. It was found that the amine (-NH2) group of DOX binds to the gold shell. An in vitro apparatus simulating the human circulatory system ...

2010-09-01

117

The cohomology ring of the GKM graph of a flag manifold of classical type  

CERN Document Server

If a closed smooth manifold $M$ with an action of a torus $T$ satisfies certain conditions, then a labeled graph $\\mG_M$ with labeling in $H^2(BT)$ is associated with $M$, which encodes a lot of geometrical information on $M$. For instance, the "cohomology" ring $\\mHT^*(\\mG_M)$ of $\\mG_M$ is defined to be a subring of $\\bigoplus_{v\\in V(\\mG_M)}H^*(BT)$, where $V(\\mG_M)$ is the set of vertices of $\\mG_M$, and is known to be often isomorphic to the equivariant cohomology $H^*_T(M)$ of $M$. In this paper, we determine the ring structure of $\\mHT^*(\\mG_M)$ when $M$ is a flag manifold of classical type directly without using the fact that $\\mHT^*(\\mG_M)$ is isomorphic to ...

2011-01-01

118

Understanding the peak asymmetry in alpha liquid scintillation with {beta}/{gamma} discrimination  

Energy Technology Data Exchange (ETDEWEB)

The peak evaluation in alpha liquid scintillation is known to be easy, mostly due to the gaussian shape of the peaks. However, we often observed a high-energy tail in addition to a pure gaussian function. This effect is only detectable with a high resolution {alpha} liquid scintillation spectrometer such as the PERALS trademark system. Indeed, its intrinsic resolution (180 keV for a 4 MeV {alpha} particle) is better than that obtained for conventional LSC spectrometers. The peak asymmetry was quantified using the Fisher's coefficient {gamma}{sub 1} (symmetry factor). We show that the main effect responsible for the asymmetry is internal conversion. Indeed, most of the even-even nuclides have low {alpha} intensity transitions leading to excited levels of their daughter nuclides. The internal conversion is almost equal to 100% and consequently produces a sum peak at higher energy. No generalization is possible for odd-even nuclides, but the knowledge of their disintegration ...

2000-07-01

119

Synthesis and photo-degradation application of WO3/TiO2 hollow spheres.  

Science.gov (United States)

A WO(3)/TiO(2) composite, hollow-sphere photocatalyst with average diameter of 320 nm and shell thickness of 50 nm was successfully prepared using a template method. UV-vis diffuse reflectance spectra illustrated that the main absorption edges of the WO(3)/TiO(2) hollow spheres were red-shifted compared to the TiO(2) hollow spheres, indicating an extension of light absorption into the visible region of the composite photocatalyst. The WO(3) and TiO(2) phases were confirmed by X-ray diffraction analysis. BET isotherms revealed that the specific surface area and average pore diameter of the hollow spheres were 40.95 m(2)/g and 19 nm, respectively. Photocatalytic experiments indicate that 78% MB was degraded by WO(3)/TiO(2) hollow spheres under visible light within 80 min. Under the same conditions, only 24% MB can be photodegraded by TiO(2). The photocatalytic mineralization of MB, catalyzed by TiO(2) and WO(3)/TiO(2), proceeded at a ...

2011-02-22

120

Level structures of  

Energy Technology Data Exchange (ETDEWEB)

Using Gammasphere data on prompt gamma rays from spontaneous fission of 252Cf, we propose energy-level schemes for 110,111,112, & 113Rh (Z=45). The fission-gamma data complement earlier studies of others on beta decay of fission products in that prompt fission gammas mainly populate yrast or near-yrast levels, while beta decay populates lower-spin levels. For the odd-A rhodium nuclei studied here, their ground bands and collective sidebands are compared with model calculations using triaxial-shaped nucleus with one odd quasi-proton. The energies and E2 transition rates are best fit by a shape slightly to the prolate side of maximum triaxiality, namely, gamma = 28 deg. The model calculations also show a K=1/2+ band with energies not in good agreement with a corresponding experimental band. The experimental 1/2+ band is regarded as an intruder band from a prolate-driving proton orbital 1/2[431] above the Z=50 closed shell. This intruder band, seen in other odd-A ...

2003-08-19

121

Kinetics of mn-based sorbents for hot gas desulfurization: Task 2 - exploratory experimental studies. Quarterly report, March 15, 1996--June 15, 1996  

Energy Technology Data Exchange (ETDEWEB)

The objective of this project is to develop a pellet formulation which is capable of achieving low sulfur partial pressures and a high capacity for sulfur, loaded from a hot fuel gas and which is readily regenerable. Furthermore the pellet must be strong for potential use in a fluidized bed and regenerable over many cycles of loading and regeneration. Regeneration should be in air or oxygen-depleted air to produce a high-concentration sulfur dioxide. Fixed-bed tests were conducted with several formulations of manganese sesquioxide and titania, and alumina They were subject to a simplified fuel gas of the oxygen-blown Shell type spiked with a 30,000ppmv concentration of H{sub 2}S. Pellet crush strengths for 4 and 2mm diameter pellets was typically 12 lbs per pellet and 4 lbs per pellet, respectively. For the most favorable of the formulations tested and under the criteria of break-through at less than 100ppmv H2S and loading temperatures of 500{degrees}C and an ...

1996-06-12

122

K/sub. beta. //K/sub. cap alpha. / transition probability ratios from the measurement of fluorescent X-ray intensities of some lanthanide compounds  

Energy Technology Data Exchange (ETDEWEB)

The effect that different chemical and physical atomic environments can have on the relative intensities of radiative electron transitions from the filling of K shell vacancies was investigated. The method used involved the detection of photoionization induced X-ray fluorescence. An experimental system based on a hyper pure germanium detector (HPGE) was used to measure the relative K-L and K-M X-ray yields from the photofluorescence of a series of lanthanide elements and compounds. A background subtraction and peak integration strategy was employed which accounted for scattering in the samples and scattering of the flux from the radioisotope photoionization sources. Analysis of the data resulted in a tabulation of relative K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios. The measured relative K/sub ..beta..//K/sub ..cap alpha../ X-ray intensity ratios were compared to the calculated values predicted by the theoretical development of ...

1987-01-01

123

K/sub #beta#//K/sub #alpha#/ transition probability ratios from the measurement of fluorescent X-ray intensities of some lanthanide compounds  

International Nuclear Information System (INIS)

The effect that different chemical and physical atomic environments can have on the relative intensities of radiative electron transitions from the filling of K shell vacancies was investigated. The method used involved the detection of photoionization induced X-ray fluorescence. An experimental system based on a hyper pure germanium detector (HPGE) was used to measure the relative K-L and K-M X-ray yields from the photofluorescence of a series of lanthanide elements and compounds. A background subtraction and peak integration strategy was employed which accounted for scattering in the samples and scattering of the flux from the radioisotope photoionization sources. Analysis of the data resulted in a tabulation of relative K/sub #beta#//K/sub #alpha#/ X-ray intensity ratios. The measured relative K/sub #beta#//K/sub #alpha#/ X-ray intensity ratios were compared to the calculated values predicted by the theoretical development of Scofield and ...

1987-01-01

124

Investigation by XRF and XRD of Zn and Fe in Fe{sub x} Zn{sub 1-x} thin films  

Energy Technology Data Exchange (ETDEWEB)

Fe{sub x}Zn{sub 1-x} alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K{beta}/K{alpha} x-ray intensity ratios of Zn and Fe in Fe{sub x}Zn{sub 1-x} thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi {sup 241}Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in Fe{sub x}Zn{sub 1-x} thin films for different values of x. The reason for this ...

2008-12-15

125

Investigation by XRF and XRD of Zn and Fe in Fex Zn1-x thin films  

International Nuclear Information System (INIS)

FexZn1-x alloys were electrochemically deposited on aluminum substrates from a sulfate bath. The K?/K? x-ray intensity ratios of Zn and Fe in FexZn1-x thin films have been experimentally studied. The energy dispersive x-ray fluorescence (EDXRF) technique was used to measure K x-ray photons. Samples were excited by using 59.5 keV photons emitted by a 50 mCi 241Am radioactive source. The emitted K x-rays were detected by an Ultra-LEGe detector having a resolution of 150 eV at 5.9 keV. In addition, the effect of bath composition on the phase structure was investigated by x-ray diffraction (XRD) analysis. The composition of the thin films was analyzed by atomic absorption spectrometry analysis. Iron content was shown to strongly affect the structure of Zn-Fe alloys. It was found that the K-shell x-ray intensity ratio changed in FexZn1-x thin films for different values of x. The reason for this change may be that the electronegativity of iron is ...

2008-12-01

126

CFD simulation of steam generator tube rupture thermal-hydraulics  

Energy Technology Data Exchange (ETDEWEB)

Several steam generator tube rupture accidents have occurred at plants in the past. In this paper the Computational Multi-Fluid Dynamics (CMFD) investigation of the horizontal steam generator thermal-hydraulics during the tube rupture accident is performed. A guillotine of a steam generator U-tube is assumed with choked flow from the primary to the secondary side of the steam generator. We have computed water and steam velocity fields, steam volume fraction distribution on the steam generator secondary (shell) side, as well as the swell level increase. The simulation results are a support to the safety analyses of the steam generator tube rupture accident. Numerical simulation is performed with the multidimensional multi-fluid modelling approach. The two-phase flow around steam generator tubes in the bundle is modelled by the porous media approach. Interfacial mass, momentum and energy transfer are modelled with the closure laws. The governing equations are solved ...

2004-07-01

127

Shell Temperatures for a Single-Heater Diffuser  

Energy Technology Data Exchange (ETDEWEB)

A new diffuser/permeator design has been proposed for a new Savannah River Site tritium project. The use of a single heater well in the center of the shell had raised concerns that the Pd/Ag coils may be shielding radiative heat transfer to the walls thus reducing Pd/Ag tube temperatures near the shell below the recommended minimum operating temperature. The diffuser was fitted with thermocouples to measure shell temperatures during testing. Tests were run with the shell evacuated, helium feed flows of 0, 1000, and 2000 sccm; bleed pressures ranging from 0 to 203 kPa, and heater temperatures of 650, 675, and 700 degrees C. Hydrogen permeation tests were run with two hydrogen/helium mixtures and feed rates to simulate 1st and 2nd stage diffuser operations. Approximately 20 hours were required to bring the diffuser from ambient temperature to steady-state conditions. For tests with a heater temperature of ...

2004-11-01

128

Photoelastic investigations of stress concentration in perforated cylindrical shells with internal pressure  

Energy Technology Data Exchange (ETDEWEB)

Cylindrical shells with regular perforation are widely used in power generating equipment and in particular in collectors 1 of the circuit of steam generators of power generating installations with water-water reactors (WWPR) The state of stress of collectors is determined by a broad spectrum of technological and operational loads, it is therefore difficult to analyze it theoretically. The aim of the present work is the experimental investigation of stresses in the cylindrical shells of collectors subjected to internal pressure, the generalization and systematization of empirical data in the form of engineering formulas and nomographs. The investigations were carried out with photoelastic three-dimensional models with the use of {open_quotes}freezing{close_quotes}. The basic characteristics of the state of stress of perforated shells (in particular those used in calculations of the strength and life of collectors) are the ...

1994-06-01

129

The level schemes of the near "4"8Ca nuclei in the frame of the pure shell model  

International Nuclear Information System (INIS)

The energy level schemes of the near "4"8Ca nuclei were investigated in the frame of the spherical shell model with pure configurations. For every nucleus two configurations were considered: the ground state configuration (GS) - calculated making use of empirical two-body interactions extracted from the level energies of the neighbouring nuclei, and the lowest energy configuration with one nucleon in the excited state (ES) - calculated making use of the two-body Kuo-Brown interactions. The results made it possible to explain the greater part of the so-called intruder levels. Comparison of the calculated and experimental level energy values epsilonsub(J)sup(calc)-epsilonsub(J)sup(exp) reveals systematic deviations of the experimental level energies from the shell model predictions. (orig.).

1986-01-01

130

Study on possible fuel layering sequence for FIREX target  

International Nuclear Information System (INIS)

A new procedure of fuel layering for the Fast Ignition Realization Experiment (FIREX) target is proposed. A conical laser guide heating technique was experimentally demonstrated in principle as the followings. It employed the target consisting of a polystyrene (PS) shell, a fill tube and a conical laser guide. At first, liquid fuel was fed into the shell and existed around the conical laser guide because the surface tension of the fuel must cause it. Then, it was solidified. The laser light provided a heat source to the conical laser guide so that the solid fuel was moved to the other interior of the shell. This process resulted in missing solid fuel around the conical laser guide. To fill the vacant space, liquid fuel was added as temperature was raised to the melting point. After the liquid fuel addition, temperature was lowered to the solidification point again. During this process, most of the solid fuel could survive.

2010-08-01

131

Shell-model calculations for neutron-rich nuclei in the 0f1p shell  

Energy Technology Data Exchange (ETDEWEB)

A new two-body interaction recently derived for nuclei in the 0f1p shell by fitting two-body matrix elements to 494 energy levels in A=41-66 nuclei, is used to investigate the neutron-rich nuclei in the vicinity of the doubly closed nuclide {sup 48}Ca. This study is of fundamental interest in providing a test for the new effective interaction away from the stability line. Masses and binding energies are calculated for a variety of neutron-rich nuclei and compared with experimental data, where available. In addition level schemes for {sup 50-52}Ca, {sup 51-52}Sc and {sup 51-52}Ti have been calculated and are compared with available experimental data. In general a good correspondence between theory and experiment is found, but some systematic discrepancies are apparent. ((orig.)).

1995-04-17

132

Shell-model calculations for neutron-rich nuclei in the 0f1p shell  

International Nuclear Information System (INIS)

A new two-body interaction recently derived for nuclei in the 0f1p shell by fitting two-body matrix elements to 494 energy levels in A=41-66 nuclei, is used to investigate the neutron-rich nuclei in the vicinity of the doubly closed nuclide "4"8Ca. This study is of fundamental interest in providing a test for the new effective interaction away from the stability line. Masses and binding energies are calculated for a variety of neutron-rich nuclei and compared with experimental data, where available. In addition level schemes for "5"0"-"5"2Ca, "5"1"-"5"2Sc and "5"1"-"5"2Ti have been calculated and are compared with available experimental data. In general a good correspondence between theory and experiment is found, but some systematic discrepancies are apparent. ((orig.)).

133

Shell effects in the symmetric-modal fission of pre-actinide nuclei  

Energy Technology Data Exchange (ETDEWEB)

Mass distributions of fragments in the low-energy fission of nuclei from {sup 187}Ir to {sup 213}At have been analysed. This analysis has shown that shell effects in symmetric-mode fragment mass yields from the fission of pre-actinide nuclei could be described if one assumes the existence of two strongly deformed neutron shells in the arising fragments with neutron numbers N{sub 1}{approx}52 and N{sub 2}{approx}68. A new method has been proposed for quantitatively describing the mass distributions of the symmetric fission mode for pre-actinides with A{approx}180-220. (orig.) 28 refs.

1998-09-21

134

Neutron inelastic scattering to octupole states in single-closed-shell nuclei  

International Nuclear Information System (INIS)

Differential cross sections for the excitation of the first octupole-vibrational state in the closed-neutron-shell nuclides "8"8Sr and "9"0Zr and in the closed-proton shell-nuclei sup(116,118,120,124)Sn by 11 MeV neutrons are presented. The distorted-wave Born approximation is used to obtain deformation lengths, delta(3"-) for each state. Results are compared with earlier measurements of inelastic proton scattering to the same states. Although limited resolution in the neutron time-of-flight spectrometer complicates the interpretation of the Sn data, the overall conclusion that deltasub(nn')(3"-) approx. deltasub(pp')(3"-) is supported by all of the measurements. (orig.).

135

Managing design and construction of the Central North Sea FPSO  

Energy Technology Data Exchange (ETDEWEB)

Shell UK Exploration and Production, operating in the North Sea on behalf of Shell UK and Esso UK is presented developing the Teal and Guillemot fields in the Central North Sea (CNS). As part of this development it contracted with Single Buoy Moorings Inc., (SBM) for the design, supply and installation of a newbuilt floating Production Storage and Offloading (FPSO) vessel. The work is executed in close cooperation between Shell Expro (Client) and SBM (Contractor) and its main sub contractors. The system is due to be installed during the third quarter of 1996. After a short description of the field development and the FPSO vessel this paper outlines the contractual arrangements and the organization set-up to perform the work. A summary of the lessons learned (by SBM) is given. The opinions expressed in this paper are entirely that of the author and may not necessarily reflect the opinion of other parties involved in the CNS ...

1996-12-31

136

Influence of the curved geometrical shape on the thin shell buckling phenomenon behaviour  

British Library Electronic Table of Contents (United Kingdom)

The present paper deals with instabilities of long homogeneous and isotropic thin shells, characterized by geometrical non-linearities and imperfections, with reference to a bent helicoidally geometrical shape of particular interest for the helicoidal steam generators tube bundle. Apparently no data exist in the literature to describe the non-linear buckling behaviour of curved thin shells under external pressure, thus, the theoretical analyses based on the classical linear elastic theory, as expected, might be inadequate to evaluate the collapse load especially if the curvature is rather large. To the purpose of determining the buckling pressure load the effects of a pre-existing level of geometrical and technological imperfection, unavoidably caused by various manufacturing processes wer...

2009-01-01

137

Enhanced antibacterial activity of bifunctional Fe3O4-Ag core-shell nanostructures  

British Library Electronic Table of Contents (United Kingdom)

We describe a simple one-pot thermal decomposition method for the production of a stable colloidal suspension of narrowly dispersed superparamagnetic Fe3O4-Ag core-shell nanostructures. These biocompatible nanostructures are highly toxic to microorganisms. Antimicrobial activity studies were carried out on both Gram negative (Escherichia coli and Proteus vulgaris) and Gram positive (Bacillus megaterium and Staphylococcus aureus) bacterial strains. Efforts have been made to understand the underlying molecular mechanism of such antibacterial actions. The effect of the core-shell nanostructures on Gram negative strains was found to be better than that observed for silver nanoparticles. The minimum inhibitory concentration (MIC) values of these nanostructures were found to be considerably lowe...

2009-01-01

138

Effect of milling process on the core-shell structures and dielectric properties of fine-grained BaTiO3-based X7R ceramic materials  

British Library Electronic Table of Contents (United Kingdom)

Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmission electron microscope, and energy dispersive spectroscopy (EDS). As the milling time extends, the dielectric constant of the ceramics increases, whereas the temperature coefficient of capacitance at 125degreeC drops quickly. The changes in dielectric properties are considered relevant to the microstructure evolution caused by the milling process. Defects on the surface of BaTiO3 particles increase because of the effects of milling process, which will make it easier for additives to diffuse into the interior grains. As the milling time increases, the shell region gets thicker a...

2009-01-01

139

A novel electrogenerated chemiluminescence sensor for pyrogallol with core-shell luminol-doped silica nanoparticles modified electrode by the self-assembled technique  

British Library Electronic Table of Contents (United Kingdom)

The core-shell luminol-doped SiO2 nanoparticles were synthesized and immobilized on the surface of chitosan film coating graphite electrode by the self-assembled technique. Then, a novel electrogenerated chemiluminescence (ECL) sensor for pyrogallol was developed based on its ECL enhancing effect for the core-shell luminol-doped silica nanoparticles. The ECL analytical performances and the sensing mechanism of this ECL sensor for pyrogallol were investigated in detail. The corresponding results showed that: compared with the conventional ECL reaction procedures by luminol ECL reaction system, the electrochemical (EC) reaction of pyrogallol and its subsequent chemiluminescence (CL) reaction occurred in the different spatial region whilst offering a high efficiency to couple the EC with the ...

2006-01-01

140

Reduced dopamine function within the medial shell of the nucleus accumbens enhances latent inhibition  

UK PubMed Central (United Kingdom)

Latent inhibition (LI) manifests as poorer conditioning to a CS that has previously been presented without consequence. There is some evidence that LI can be potentiated by reduced mesoaccumbal dopamine...Full Text Available

2011-03-01

141

Principles of room air flow; Grundlagen der Raumluftstroemung  

Energy Technology Data Exchange (ETDEWEB)

The following subjects are dealt with: physics of indoor air flow, flow in individual rooms, exchange of air and pollution between individual building zones and with the outside world, thermal coupling with the building shell, thermal comfort and air quality, evaluation of the ventilation. figs., tabs., refs.

1994-12-31

142

Parity-projected shell model Monte Carlo level densities for fp-shell nuclei  

International Nuclear Information System (INIS)

We calculate parity-dependent level densities for the even-even isotopes "5"8","6"2","6"6Fe and "5"8Ni and the odd-A nuclei "5"9Ni and "6"5Fe using the shell model Monte Carlo method. We perform these calculations in the complete fp-gds shell-model space using a pairing+quadrupole residual interaction. We find that, due to pairing of identical nucleons, the low-energy spectrum is dominated by positive parity states. Although these pairs break at around the same excitation energy in all nuclei, the energy dependence of the ratio of negative-to-positive parity level densities depends strongly on the particular nucleus of interest. We find equilibration of both parities at noticeably lower excitation energies for the odd-A nuclei "5"9Ni and "6"5Fe than for the neighboring even-even nuclei "5"8Ni and "6"6Fe.

2007-06-01

143

Observations of late-type young stars in the Rho Oph dark cloud  

Energy Technology Data Exchange (ETDEWEB)

We present photoelectric BVRI photometry for 16 T Tau and related stars in the Rho Oph dark cloud, as well as vidicon spectroscopic observations for nine stars. The color excesses of these stars favor circumstellar dust shells as the source of the observed infrared excesses.

1980-04-01

144

Normal parity states in lithium isotopes  

Energy Technology Data Exchange (ETDEWEB)

Shell model calculations are reported for the properties of normal parity states of /sup 7/Li, /sup 8/Li and /sup 9/Li. Fits to new experimental data are displayed, some ambiguities resolved, and structure information provided for help in further investigations.

1983-11-21

147

Analytic properties of nonrelativistic two-body off-shell amplitudes II. Off-shell generalizations of the Jost formalism  

International Nuclear Information System (INIS)

The connections between several studies of the off-shell amplitude, based on apparently different criteria, are first clarified and expressed through more coincise operator notion. In all cases the resolution of the underlying dynamical relations is reduced to a two-step procedure. Underconditions which are discussed, the latter implies only Volterra-like integral equations followed by simple quadratures and algebraic operations. Then it is shown that the off-shell generalizations of the Jost formalism which are defined by such approaches can as well be introduced without reference to any explicit dynamical framework. Examples are given specifying in such model independent ways the main properties of the associated Jost-type functions. The relative interest of different representations built with these functions is also examined, and on this occasion new three-separable-term approximations are a useful guideline for introducing similar ...

148

Vibrations of circular cylindrical shells  

Science.gov (United States)

An exact solution method for the free vibration problem of thin circular cylindrical shells is presented. The differential equations of motion are solved directly with the use of simple Fourier series as the modal displacement functions. Stokes' transformation is exploited to obtain correct series expressions for the derivatives of the Fourier series. From this method an explicit expression of the exact frequency equation can be obtained for any kind of boundary conditions. The accuracy of the present method is checked against available data. The proposed method is then used to find the modal characteristics of the thermal liner of the Fast Test Reactor (FTR). The numerical results obtained are compared with finite element method solutions. (auth)

1975-07-01

149

Photon-induced K-shell X-ray intensity ratio for elements with 74#<=#Z#<=#92  

International Nuclear Information System (INIS)

The K-shell X-ray intensity ratios for W, Au, Tl, Pb, Bi, Th and U were measured at a photon incident energy of 121.9 keV from "5"7Co radionuclide. A comparison between the experimental results and the theoretically calculated values shows that the experimental results are, in general, higher than the theoretical values. The measured intensities are regarded to be reported for the first time. (author) 9 refs.; 1 tab.

1989-01-01

150

Persistence of the N=28 shell closure far from stability  

Science.gov (United States)

The masses of 16 neutron-rich nuclei in the mass range from 35 to 45 have been measured using a direct time of flight technique following the fragmentation of a {sup 48}Ca beam at 60 MeV/nucleon. The masses of {sup 35,36}Mg, {sup 38}Al, {sup 39,40}Si, {sup 42,43}P and {sup 43,44}S are reported for the first time. Preliminary analysis shows that the N=28 shell closure persists, even if weakened by the large neutron excess.

1998-12-21

151

Persistence of the N=28 shell closure far from stability  

International Nuclear Information System (INIS)

The masses of 16 neutron-rich nuclei in the mass range from 35 to 45 have been measured using a direct time of flight technique following the fragmentation of a "4"8Ca beam at 60 MeV/nucleon. The masses of "3"5","3"6Mg, "3"8Al, "3"9","4"0Si, "4"2","4"3P and "4"3","4"4S are reported for the first time. Preliminary analysis shows that the N=28 shell closure persists, even if weakened by the large neutron excess.

1998-12-21

152

Particle-hole excitations in N=50 nuclei  

Energy Technology Data Exchange (ETDEWEB)

Energy levels in N=50 nuclei are calculated allowing single-particle excitations from the p{sub 1/2} and g{sub 9/2} shells into the d{sub 5/2}, s{sub 1/2}, d{sub 3/2}, and g{sub 7/2} shells. Important parts of the interaction are determined by least-squares fits to known levels. Agreement with experiment is very good. The high-spin particle-hole states appear to be mainly yrast levels in mass 93 and higher, but are not in {sup 90}Zr. {copyright} {ital 1997} {ital The American Physical Society}

1997-03-01

153

Measurement of the K-shell ionization probability across a wide resonance: /sup 88/Sr(p,p/sub 0/) at 6. 06 MeV  

Energy Technology Data Exchange (ETDEWEB)

We have measured the K-shell ionization probability across the 6.06-MeV resonance in /sup 88/Sr(p,p/sub 0/) where the resonance width is large compared to the energy transferred to the electron. The results are found to agree quantitatively with the theory developed by Blair and Anholt. The effect of the time delay on the ionization probability, introduced by the nuclear scattering at the resonance energy, is discussed.

1982-09-01

154

Isomeric island in the vicinity of 66Fe  

Science.gov (United States)

An island of isomers have recently been observed on both sides of the N=40 shell below the Ni isotopes. Isomeric states in the 65Fe and 67Fe allow the knowledge of the single particle structure around the {nu}g9/2 shell. Moreover, the excitation energy of the first 2+ and 4+ states in the 68Fe have been established by {beta}-{gamma} correlation. The evolution of the structure of the Fe isotopes going far away from the valley of stability is, for the first time, given for N>40.

2006-04-26

155

Isomeric island in the vicinity of 66Fe  

International Nuclear Information System (INIS)

An island of isomers have recently been observed on both sides of the N=40 shell below the Ni isotopes. Isomeric states in the 65Fe and 67Fe allow the knowledge of the single particle structure around the #nu#g9/2 shell. Moreover, the excitation energy of the first 2+ and 4+ states in the 68Fe have been established by #beta#-#gamma# correlation. The evolution of the structure of the Fe isotopes going far away from the valley of stability is, for the first time, given for N>40.

2006-04-26

156

Inner-shell excitation of intrinsic luminescence and resonantly excited X-ray fluorescence at Be 1s edge in oriented BeO crystals  

International Nuclear Information System (INIS)

The results of studies of the time-resolved luminescence of self-trapped excitons (STE) with different multiplicity as well as the X-ray emission in oriented BeO crystals under excitation in the vicinity of the 1 s Be photoabsorption edge are presented. The branching of the electronic excitations relaxation depends strongly on the crystal orientation after the inner-shell excitation. The common features between the processes of the STE luminescence and resonantly excited X-ray fluorescence have been discussed.

2007-05-21

157

Gold and gold-silver core-shell nanoparticle constructs with defined size based on DNA hybridization  

Energy Technology Data Exchange (ETDEWEB)

Nanoparticles represent versatile building blocks in material science and nanotechnology. Thereby, the defined assembly of nanostructures (13 and 56 nm in diameter, respectively) is of significant importance. Short DNA sequences can be bound to the nanoparticle surface thus enabling highly specific DNA hybridization-driven events that direct the formation of nanoparticle constructs.In this paper, examples for the defined formation of gold nanoparticle constructs are demonstrated. In addition, gold-silver core-shell nanoparticles are introduced as further building blocks for the hybridization-controlled formation of nanoparticle constructs.

2009-04-15

158

Coherent correlation enhancement of outer shell photoionization cross sections of alkali-like ions  

Energy Technology Data Exchange (ETDEWEB)

An alkali-like ion interaction with inner electrons of an alkali-like ion leads to a significant increase in the photoionization cross section of the outer s electron. This occurs not only for ground-state ions with one s electron in the outer shell, but also when the outer s electron is in an excited state. The reason for this amplification, in addition to coherent enhancement in summing of the correlation amplitudes, is that the zero in the direct amplitude occurs below threshold. This leads to a constructive interference with the correlation amplitude above the photoionization threshold, in contrast to a destructive interference in the case of a neutral atom with the same electronic configuration, for which the zero occurs above threshold. Results of this research were published.

1995-08-01

159

An off-shell I.R. regularization strategy in the analysis of collinear divergences  

CERN Document Server

We present a method for the analysis of singularities of Feynman amplitudes based on the Speer sector decomposition of the Schwinger parametric integrals combined with the Mellin-Barnes transform. The sector decomposition method is described in some details. We suggest the idea of applying the method to the analysis of collinear singularities in inclusive QCD cross sections in the mass-less limit regularizing the forward amplitudes by an off-shell choice of the initial particle momenta. It is shown how the suggested strategy works in the well known case of the one loop corrections to Deep Inelastic Scattering.

2011-01-01

160

Activated charcoal from coconut shell using ZnCl{sub 2} activation  

Energy Technology Data Exchange (ETDEWEB)

In this study attempts have been made to utilize biomass residues in a proper and efficient way. As a part of these attempts activated charcoal has been produced from coconut shell. The effects of temperature, time and impregnation ratio on activation and yield have also been studied. Experimental results show that higher temperature produces better activation but lower yield. The optimum values for activation time and impregnation ratio in producing activated charcoal were 50 min and 40%, respectively, at 600{sup o}C. (Author)

2002-05-01

161

A mathematical model for a thermally coupled humidification?dehumidification desalination process  

British Library Electronic Table of Contents (United Kingdom)

The humidification?dehumidification process is an interesting technique that has been adapted for water desalination. Previous works experimentally investigated desalination processes in the shell and tube columns, where the humidification and dehumidification were thermally coupled and simultaneously performed at the tube and shell sides, respectively. In this work, a comprehensive steady-state mathematical model was developed for such a humidification?dehumidification desalination process by taking into account the heat and mass balances on both sides of the desalting column, the mass transfer rate at the humidification side, and the heat transfer rate between the dehumidification side and humidification side. Meanwhile, the mass transfer coefficient at the humidification side and the to...

2006-01-01

162

Inflow behavior observation of molten mold powder between mold and solidified shell by continuous casting simulator using Sn-Pb alloy and stearic acid  

Energy Technology Data Exchange (ETDEWEB)

High productivity and high quality slab machine have been recently required in continuous casting process to lower the cost of steel production. It is important to know the inflow behavior of mold powder between mold and solidified shell to develop higher-speed casting. The purpose in this study is to make clear she mechanism of lubrication between mold and solidified shell. Sn-5mass%Pb alloy and stearic acid were used as substituted of liquid steel and molten mold powder in the experiment simulated continuous casting machine. Direct observation on inflow behavior of mold powder was made experimentally by a digital video camera. The friction force between mold and solidified shell was measured by a load cell which was set under the mold. Mold powder flowed into the aperture between mold and solidified shell during both positive strip time period and negative strip time period and the amount of powder ...

2000-06-01

163

Study of J/Psi decays into eta Kstar Kstar-bar  

CERN Document Server

We report the first observation of $\\mPJpsi \\to \\mPeta\\mPKst\\mAPKst$ decay in a $\\mPJpsi$ sample of 58 million events collected with the BESII detector. The branching fraction is determined to be $(1.15 \\pm 0.13 \\pm 0.22)\\times 10^{-3}$. The selected signal event sample is further used to search for the $\\mPY$ resonance through $\\mPJpsi \\to \\mPeta \\mPY, \\mPY\\to\\mPKst\\mAPKst$. No evidence of a signal is seen. An upper limit of \\mathrm{Br}(\\mPJpsi \\to \\mPeta \\mPY)\\cdot\\mathrm{Br}(\\mPY\\to\\mPKst\\mAPKst) < 2.52\\times 10^{-4} is set at the 90% confidence level.

2009-01-01

164

The Hydrodynamic Environment for the s Process in the He-Shell Flash of AGB Stars  

CERN Document Server

The He-shell flash convection in AGB stars is the site for the high-temperature component of the s-process in low- and intermediate mass giants, driven by the Ne22 neutron source. [...] The upper convection boundary plays a critical role during the H-ingestion episode that may lead to neutron-bursts in the most metal-poor AGB stars. We address these problems through global 3-dimensional hydrodynamic simulations including the entire spherical He-shell flash convection zone (as oposed to the 3D box-in-a-star simulations). An important aspect of our current effort is to establish the feasibility of our appoach. We explain why we favour the explicit treatment over the anelastic approximation for this problem. The simulations presented in this paper use a Cartesian grid of 512^3 cells and have been run on four 8-core workstations for four days to simulate ~5000s, which corresponds to almost ten convective turn-over times. The convection layer ...

2009-01-01

165

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

166

Structure of molten alkali halides  

Energy Technology Data Exchange (ETDEWEB)

The results of X-ray and neutron diffraction experiments on molten alkali halides in which some data of our experiments by X-ray diffraction such as those of molten LiCl, NaCl, KCl, LiBr and KBr are included were summarized. The first peak positions in the radial distribution function in molten alkali halides by X-ray or neutron diffraction experiments are always longer than those by computer simulations and the differences of 0.1 -- 0.3 A exceed the experimental error. It seems to be due to the deformation of the electron shell. In the computer simulation, the shell model which has the spherical deformation was expected to have a closer value of the first peak position to the experimental one than the rigid ion model by taking the polarization of ions. However, no change in the first peak position was found. Therefore, the non-spherical deformation of electron shell at the point where ions are in contact with each other ...

1982-06-01

167

Structure of molten alkali halides  

International Nuclear Information System (INIS)

The results of X-ray and neutron diffraction experiments on molten alkali halides in which some data of our experiments by X-ray diffraction such as those of molten LiCl, NaCl, KCl, LiBr and KBr are included were summarized. The first peak positions in the radial distribution function in molten alkali halides by X-ray or neutron diffraction experiments are always longer than those by computer simulations and the differences of 0.1 -- 0.3 A exceed the experimental error. It seems to be due to the deformation of the electron shell. In the computer simulation, the shell model which has the spherical deformation was expected to have more closer value of the first peak position to the experimental one than the rigid ion model by taking the polarization of ions. However, no change in the first peak position was found. Therefore, the non-spherical deformation of electron shell at the point where ions are in contact with each other ...

1982-01-01

168

Some Statistical Procedures for Evaluation of the Relative Contribution for Yield Components in irradiated populations of Peanut (Arachis hypogaea L  

International Nuclear Information System (INIS)

The present investigation was conducted at Ismaillia Research Station-Agricultural Research Center, Ismaillia Governorate, during the two successive seasons of 2000 and 2001. Two varieties of peanut (Arachis hypogaea L) namely Giza 4 and Giza 5 were treated with gamma ray doses; 10,15, 20, 25 Kr in order to induce genetic variability and to study the importance of the relative contribution of peanut yield components by employing some statistical procedures, i.e. simple correlation, multiple linear regression and stepwise regression analysis. The results showed that, there was significant positive correlation between seed yield/plant and no. of pods/plant, 100 seed weight, shelling percentage and pod yield/plant, and there was significant positive correlation between pod yield/plant and no of seed/plant,100 pod weight and 100 seed weight. The multiple linear regression analysis clearly showed that the relative contribution (R"2%) of the yield components, no. of ...

2003-04-01

169

Parity-projected shell model Monte Carlo level densities for medium-mass nuclei  

International Nuclear Information System (INIS)

We investigate the effects of single-particle structure and pairing on the equilibration of positive and negative-parity level densities for the even-even nuclei "5"8","6"2","6"6Fe and "5"8Ni and the odd-A nuclei "5"9Ni and "6"5Fe. Calculations are performed using the shell model Monte Carlo method in the complete fp-gds shell-model space using a pairing+quadrupole type residual interaction. We find for the even-even nuclei that the positive-parity states dominate at low excitation energies due to strong pairing correlations. At excitation energies at which pairs are broken, single-particle structure of these nuclei is seen to play the decisive role for the energy dependence of the ratio of negative-to-positive parity level densities. We also find that equilibration energies are noticeably lower for the odd-A nuclei "5"9Ni and "6"5Fe than for the neighboring even-even nuclei "5"8Ni and "6"6Fe.

2008-11-11

170

High-spin structure of odd $^{71-81}$Ga isotopes with shell model  

CERN Document Server

The recently measured experimental data of Argonne National Laboratory for high-spin states in neutron-rich $^{71,73,75,77}$Ga isotopes have been interpreted in the framework of large-scale shell model. Calculations have been performed in $f_{5/2}pg_{9/2}$ model space with two recent effective shell model interactions, JUN45 and jj44b. We also predict high-spin states for $^{79,81}$Ga, where very little is known experimentally. The calculated results show that existence of band structure built on top of the 3/2$^-$, 5/2$^-$ and 9/2$^+$ levels in $^{71-77}$Ga. The collective structure reflected in experimental data is not well reproduced in calculated values. The calculated positive parity states in $^{71,73,75}$Ga are higher in energy in comparison to experimental finding, while for $^{77,79}$Ga, the positive parity states are in better agreement. Both the interactions predict, leading configuration of $\\pi(f_{5/2}^3)$ and ...

2011-01-01

171

ESR dosimetry of irradiated chicken legs and chicken eggs  

Energy Technology Data Exchange (ETDEWEB)

Ionising radiation induces stable free radicals in chicken bones and in the shell of chicken eggs which can be detected, by the electrons spin resonance (ESR) technique, well beyond the shelf-life of the food and can be used for dosimetry. The method usually adopted to evaluate ``a posteriori`` the dose given during the ionising radiation treatment of food, is the dose additive method. To assess the dose, the ESR signal amplitude of the irradiated food (bone or egg shell in the present case) is measured and then the dose-effect relationship is obtained by re-irradiating the sample with some additive doses (usually of 1 kGy). The dose-effect curve is back-extrapolated and the initial given dose determined. At the Istituto Superiore di Sanita (ISS), Rome, Italy, a research programme was approved two years ago aimed to, (1) study new methodological approaches for ESR dose assessment, and (2) analyse the factors which may influence the ESR readout ...

1996-12-31

172

Design/build/mockup of the Waste Isolation Pilot Plant gas generation experiment glovebox  

Energy Technology Data Exchange (ETDEWEB)

A glovebox was designed, fabricated, and mocked-up for the WIPP Gas Generation Experiments (GGE) being conducted at ANL-W. GGE will determine the gas generation rates from materials in contact handled transuranic waste at likely long term repository temperature and pressure conditions. Since the customer`s schedule did not permit time for performing R&D of the support systems, designing the glovebox, and fabricating the glovebox in a serial fashion, a parallel approach was undertaken. As R&D of the sampling system and other support systems was initiated, a specification was written concurrently for contracting a manufacturer to design and build the glovebox and support equipment. The contractor understood that the R&D being performed at ANL-W would add additional functional requirements to the glovebox design. Initially, the contractor had sufficient information to design the glovebox shell. Once the shell design was approved, ANL-W ...

1996-10-01

173

Coaxial nanocables of p-type zinc telluride nanowires sheathed with silicon oxide: synthesis, characterization and properties  

International Nuclear Information System (INIS)

Coaxial nanocables with a single-crystalline zinc telluride (ZnTe) nanowire core and an amorphous silicon oxide (SiO_x) shell have been synthesized via a simple one-step chemical vapor deposition (CVD) method on gold-decorated silicon substrates. The single-crystal ZnTe nanowire core is in zinc-blende structure along the [111] direction, while the uniform SiO_x shell fully covers the core with no observable pin-hole or crack. Formation mechanisms of the ZnTe-SiO_x nanocables are discussed. The ZnTe nanowire core shows p-type electrical properties while the SiO_x shell acts as an effective insulating layer. The ZnTe-SiO_x nanocables may have potential applications in nanoscale devices, such as p-type FETs and nanosensors.

2009-11-11

174

Characterization and reactivity of Fe3O4/FeMnOx core/shell nanoparticles for methylene blue discoloration with H2O2  

British Library Electronic Table of Contents (United Kingdom)

A magnetic core/shell Fe3O4/FeMnOx catalyst was prepared by a simple oxidation-precipitation method. The catalyst was characterized by X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and cyclic voltammetry. The characterization studies verified that Fe3O4 core was coated with a layer of Fe-Mn oxide. The Fe3O4/FeMnOx was found to be an effective and stable heterogeneous catalyst for the discoloration of methylene blue (MB) in aqueous solution by H2O2. The high catalytic activity is due to the FeMnOx shell, which not only increased the surface hydroxyl groups, but also enhanced the interfacial electron transfer. The discoloration of MB could be due to the decomposition of H2O2 into ?OH ...

2011-01-01

175

The investigations on K and L X-ray fluorescence parameters of gold compounds  

British Library Electronic Table of Contents (United Kingdom)

The study aimed to determine the chemical effects on the K and L X-ray intensity ratios and the K and L X-ray production cross sections for gold compounds. The K shell fluorescence yields and L shell average yields were also investigated. The samples were excited by 59.5keV ?-rays from an 241Am annular radioactive source and 123.6keV ?-rays from a 57Co annular radioactive source. K and L X-rays emitted from samples were counted by an Ultra-LEGe detector with a resolution of 0.150keV at 5.9keV. The experimental values were compared with theoretical, the semi-empirical and other experimental values.

2010-01-01

176

The Triton project -- A North Sea subsea challenge  

Energy Technology Data Exchange (ETDEWEB)

Three companies--Amerada Hess Ltd., Shell Expro (a 50/50 joint partnership between Shell and Esso) and Texaco--have joined forces in a project that will combine their expertise. The Triton project will allow three fields (Bittern, Guillemot West and Gullemot Northwest) to be developed simultaneously using subsea technology, with the wellheads on the seafloor and 68 miles (110 km) of flowlines taking oil and gas produced from the fields to a central floating production storage and offloading (FPSO) vessel. These fields are located in the central area of the North Sea, about 118 miles from Aberdeen in 295 ft of water. The paper discusses the development of the fields, subsea technology, technical challenges, laying the pipeline, and project completion.

1998-11-01

177

Synthesis and enhanced light absorption of alumina matrix nanocomposites containing multilayer oxide nanorods and silver nanoparticles  

British Library Electronic Table of Contents (United Kingdom)

In this paper, multilayer oxide nanorods were deposited in the nanopores of anodic aluminum oxide (AAO) via solution infiltration followed by heat treatment. The nanorods have a core-shell structure. First, the shell (nanotube) with the thickness of about 40nm was made of TiO"2 through the hydrolysis of (NH"4)"2TiF"6. Second, silver nanoparticles with the diameter of about 3nm were added into the TiO"2 layer through thermal decomposition of AgNO"3 at elevated temperatures. Then, cylindrical cores (nanorods) of CoO and ZnO with 200nm diameter were prepared, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the structure and composition of the nanorods. UV-vis light absorption measurements in the wavelength range from 350 to...

2011-01-01

178

Synthesis and characterization of Co-Ag core-shell nanoparticles  

Energy Technology Data Exchange (ETDEWEB)

A micellar method has been used to prepare silver-coated cobalt (Co-Ag) nanoparticles. The synthesized particles have been deeply characterized by several methods, i.e., XRD, UV-Vis, TEM, XPS, and electrochemical techniques. There is every indication that the obtained particles show a truly core-shell structure. All the nanoparticles obtained under different conditions are in the size range 3-5 nm. High-resolution TEM (HRTEM), Fast Fourier Transformation (FFT), and Selected Area Electron Diffraction (SAED) indicated that the presence of hcp-Co and fcc-Ag, in which cobalt is located in the central area; meanwhile silver is at the edges of the nanoparticle. The absorption band of the Co-Ag colloid shifts to a longer wavelength and broadens relative to that of pure silver colloid. Voltammetric characterization allowed to determine the coverage of the cobalt core.

2010-08-15

179

Superphenix 1 steam generator fabrication  

Energy Technology Data Exchange (ETDEWEB)

The Superphenix 750-MW (thermal), once-throughtype steam generators are the result of over 10 years of intensive research and development. Detailed design and manufacture of the components lasted from 1977 to 1982. The main difficulties encountered during the construction of these prototype units concerned: demonstration of satisfactory high-temperature properties of Alloy 800 tubes; proven resistance of tube welds to thermal fatigue and of structures and shells to sodium/ water reaction effects; prevention of the tube bundle to flow-induced vibration; necessity of manual welding of shells to prevent hot cracking hazards related to the boron content of the steel; and welding of heat exchange tubes. None of these difficulties, however, invalidated initial major design choices, but provided a wealth of technical and technological experience and knowledge for the steam generators of the future. Plans for the future include revision of the ...

1985-02-01

180

Sub-barrier fusion reactions for synthesis of "2"9"8114  

International Nuclear Information System (INIS)

Favorable reaction channels are searched for in order to obtain the superheavy element "2"9"8114. The interaction energy is supposed to comply with the adiabatic hypothesis. Concerning the deformation energy, a very complete binary macroscopic-microscopic energy method is used to perform calculations. Deformed two-center shell model provides the energy level schemes for shell effects. Yukawa-plus-exponential model gives the macroscopic (liquid drop) part of the total energy. The mass tensor is obtained by the Werner-Wheeler irrotational flow hypothesis. Finally the minimization of the multidimensional action integral produces the highest penetrability values. Kr-projectile reactions provide the best pairs, although generally the presentabilities are very low. (author)

2005-01-01

181

Structure analysis of cation selective Cr-goethite as protective rust of weathering steel  

International Nuclear Information System (INIS)

We have performed extended X-ray absorption fine structure (EXAFS) analysis for artificial Cr-goethite to elucidate the local structure around Cr in Cr-goethite. The spectra were obtained using synchrotron radiation X-rays at the Photon Factory in Tsukuba. The first shell contributions were isolated by Fourier filtering EXAFS data, and the inverse Fourier transformed single-shell data were analyzed using a curve fitting method. The results show that Cr is coordinated with (7#+-#1)O"2"- ions. The protective characteristics of the Cr-goethite protective rust layer on weathering steel can be interpreted in terms of the O"2"- coordination around Cr"3"+ resulting in the creation of negative fixed charge in the Cr-goethite particles. (author)

2005-02-01

182

Running couplings and operator mixing in the gravitational corrections to coupling constants  

CERN Document Server

The use of a running coupling constant in renormalizable theories is well known, but the implementation of this idea for effective field theories with a dimensional coupling constant is in general less useful. Nevertheless there are multiple attempts to define running couplings including the effects of gravity, with varying conclusions. We sort through many of the issues involved, most particularly the idea of operator mixing and also the kinematics of crossing, using calculations in Yukawa and lambda phi^4 theory as illustrative examples. We remain in the perturbative regime. In some theories with a high permutation symmetry, such as lambda phi^4, a reasonable running coupling can be defined. However in most cases, such as Yukawa and gauge theories, a running coupling fails to correctly account for the energy dependence of the interaction strength. As a byproduct we also contrast on-shell and off-shell renormalizaton schemes and show that ...

2010-01-01

183

Rotary Mode Core Sample System availability improvement  

Energy Technology Data Exchange (ETDEWEB)

The Rotary Mode Core Sample System (RMCSS) is used to obtain stratified samples of the waste deposits in single-shell and double-shell waste tanks at the Hanford Site. The samples are used to characterize the waste in support of ongoing and future waste remediation efforts. Four sampling trucks have been developed to obtain these samples. Truck I was the first in operation and is currently being used to obtain samples where the push mode is appropriate (i.e., no rotation of drill). Truck 2 is similar to truck 1, except for added safety features, and is in operation to obtain samples using either a push mode or rotary drill mode. Trucks 3 and 4 are now being fabricated to be essentially identical to truck 2.

1995-02-28

184

Photon-induced L-shell x-ray intensity ratio for elements with 73 #<=# Z #<=#83 in the energy range 17 #<=# E #<=# 47 keV  

International Nuclear Information System (INIS)

The L-shell x-ray intensity ratios I(L_#beta#)/I(L_#alpha#) and I(L_#gamma#)/I(L_a_l_p_h_a) for elements with 73 #<=# Z #<=# 83 have been measured at photon incident energies of 17.8, 25.8 and 46.9 keV. The emitted x-rays were measured with a Si(Li) detector system. The results for Re, Pt and Tl are being reported for the first time. A comparison is made of the experimental results with the calculated values obtained by using the theoretical x-ray emission rates, subshell ionisation cross sections, subshell fluorescence yields and Coster-Kronig transition probabilities. The experimental results are in reasonable agreement with the theoretical values. (author).

1988-01-01

185

On the evolution of supernova remnants: Pt. 2  

International Nuclear Information System (INIS)

Supernova explosions within wind-driven bubbles are studied with 2D hydrodynamical calculations. Two different density distributions for the ejecta are considered: (i) a smooth, unfragmented power-law stratification, and (ii) a fragmented distribution. As in 1D models, the presence of the shell of interstellar swept-up matter causes the rapid evolution of the remnant to the radiative phase. The main 2D effects, for both fragmented and unfragmented ejecta, include: (i) substantial chaotic deviations from a purely radial flow in the remnant interior, (ii) efficient turbulent mixing between the ejecta and the shocked wind, resulting in homogenization of the former wind cavity, and (iii) severe distortion of the wind-driven shell by cooling and Rayleigh-Taylor instabilities. (author).

186

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

187

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

188

Numerical and experimental investigation of shellside characteristics for RODbaffle heat exchanger  

Energy Technology Data Exchange (ETDEWEB)

RODbaffle heat exchanger is a kind of shell-and-tube heat exchanger with eminent performance. Because of the characteristics of tube bundle support structure, fluid flow on shellside is longitudinal and periodical, and fluid flow is of symmetry in landscape orientation. According to the fluid flow characteristics on shellside and ignoring the impact of inlet, outlet and shell wall, a periodic flow unit duct was taken as the simplified model of the shellside to perform numerical simulation by using CFD code, FLUENT. It was found that the both errors in magnitude of the main fluid velocities and heat transfer coefficients between results of simulation and that of experiment or correlations are less than 10%, and the errors of pressure drop between simulation and correlation are no more than 20%. The detailed characteristics and relation of fluid flow and heat transfer on shellside of the RODbaffle heat exchanger were analyzed using the simulation ...

2008-05-15

189

New derivation of the Marshalek-Okubo realization of the shell-model algebra SO(2. nu. +1) for even and odd systems with. nu. single-particle levels  

Energy Technology Data Exchange (ETDEWEB)

In recent years, the method for unitarizing nonunitary Dyson boson realizations of shell-model algebras has been both generalized and substantially simplified through the introduction of overtly group-theoretical methods. In this paper, these methods are applied to the boson-odd-particle realization of the algebra SO(2..nu..+1) for ..nu.. single-particle levels, adapted to the group chain SO(2..nu..+1) contains SO(2..nu..) contains U(..nu..), which Marshalek first derived by brute force summation of a Taylor expansion and later Okubo by a largely algebraic technique.

1988-04-01

190

K-shell x-ray production cross sections of selected elements from Ti to Y for 0.5- to 2.5-MeV alpha-particle bombardment  

International Nuclear Information System (INIS)

K-shell x-ray production cross sections and K#beta#/K#alpha# ratios have been measured for thin targets of Ti, V, Cr, Fe, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, and Y for 0.5- to 2.5-MeV alpha particles. The experimental values are compared to the nonrelativistic plane-wave Born approximation (PWBA), the binary-encounter approximation, and the PWBA with binding energy and Coulomb deflection corrections. The PWBA with corrections provides the best agreement with the experimental cross sections.

191

Forward on the N=Z line with GASP  

Energy Technology Data Exchange (ETDEWEB)

The experimental study of the proton-rich nuclei close to the N=Z line is a constant challenge for nuclear spectroscopy, mainly due to the difficulty to produce them with the currently available beam/target combinations. Significant advances on this direction were obtained from experiments performed with the GASP array during the last two years: the yrast line of {sup 84}Mo was extended up to 10{sup +}, {sup 88}Ru observed for the first time, and the N=Z+1 line was mapped from {sup 81}Zr to {sup 95}Ag. These new results allow us to have a more complete image of the transition from the well-deformed shell closure at N,Z=40 to the spherical-shell closure at N,Z=50, and highlights some particular effects that can be observed only in the vicinity of the N=Z line. (orig.)

2004-04-01

192

Forward on the N=Z line with GASP  

International Nuclear Information System (INIS)

The experimental study of the proton-rich nuclei close to the N=Z line is a constant challenge for nuclear spectroscopy, mainly due to the difficulty to produce them with the currently available beam/target combinations. Significant advances on this direction were obtained from experiments performed with the GASP array during the last two years: the yrast line of "8"4Mo was extended up to 10"+, "8"8Ru observed for the first time, and the N=Z+1 line was mapped from "8"1Zr to "9"5Ag. These new results allow us to have a more complete image of the transition from the well-deformed shell closure at N,Z=40 to the spherical-shell closure at N,Z=50, and highlights some particular effects that can be observed only in the vicinity of the N=Z line. (orig.)

2004-04-01

193

Feynman rules in N=2 projective superspace. II. Massive hypermultiplets  

International Nuclear Information System (INIS)

For pt.I see ibid., vol.516, p.426-48, 1998. Manifest N=2 supersymmetric hypermultiplet mass terms can be introduced in the projective N=2 superspace formalism. In the case of complex hypermultiplets, where the gauge covariantized spinor derivatives have an explicit representation in terms of gauge prepotentials, it is possible to interpret such masses as vacuum expectation values of an Abelian vector multiplet. The duality transformation that relates the N=2 off-shell projective description of the hypermultiplet to the on-shell description involving two N=1 chiral superfields allows us to obtain the massive propagators of the N=1 complex linear fields in the projective hypermultiplet. The N=1 massive propagators of the component superfields in the projective hypermultiplet suggest a possible ansatz for the N=2 massive propagator, which agrees with an explicit calculation in N=2 superspace. (orig.).

194

Electrorheological RayleighTaylor instability at the interface between a porous layer and thin shell with poorly conducting couple stress fluid  

British Library Electronic Table of Contents (United Kingdom)

This paper is concerned with the study of the Electrorheological RayleighTaylor instability (ERTI) at the interface between a densely packed saturated poorly conducting couple stress porous layer accelerated by a lighter poorly conducting couple stress fluid in a thin shell in the presence of a transverse electric field and laser radiation. A simple theory based on fully developed flow approximations is used to derive the dispersion relation for the growth rate of ERTI. The cutoff and the maximum wave numbers and the corresponding maximum frequencies are obtained. It is shown that the effects of couple stress parameter and the electric field reduce the growth rate considerably compared to a non-conducting fluid in the absence of an electric field. These are favorable to control the surface...

2011-01-01

195

Electrodeposition and magnetic properties of three-dimensional bulk and shell nickel mesostructures  

British Library Electronic Table of Contents (United Kingdom)

In this paper we demonstrate the electrodeposition of nickel, a common ferromagnetic material, in various magnetically desirable shapes including nanowires, nanoparticles and highly faceted shells. In order to obtain three dimensional mesostructures, the electrochemical deposition of nickel was performed on highly oriented pyrolytic graphite (HOPG) under different electrolyte composition and deposition potential conditions. Under potentiostatic deposition at one distinct potential negative with respect to the reversible potential of nickel, three stages of nucleation and growth take place leading to a complex morphology of deposits. However, dual-pulse potential deposition and electrodeposition in low pH solutions causing hydrogen evolution, lead to nickel deposits in the form of nanowires...

2011-01-01

196

Detection of Microcalcification in Mammograms Using Wavelet Transform and Fuzzy Shell Clustering  

CERN Document Server

Microcalcifications in mammogram have been mainly targeted as a reliable earliest sign of breast cancer and their early detection is vital to improve its prognosis. Since their size is very small and may be easily overlooked by the examining radiologist, computer-based detection output can assist the radiologist to improve the diagnostic accuracy. In this paper, we have proposed an algorithm for detecting microcalcification in mammogram. The proposed microcalcification detection algorithm involves mammogram quality enhancement using multirresolution analysis based on the dyadic wavelet transform and microcalcification detection by fuzzy shell clustering. It may be possible to detect nodular components such as microcalcification accurately by introducing shape information. The effectiveness of the proposed algorithm for microcalcification detection is confirmed by experimental results.

2010-01-01

197

An new derivation of the Marshalek-Okubo realization of the shell-model algebra SO(2#nu#+1) for even and odd systems with #nu# single-particle levels  

International Nuclear Information System (INIS)

In recent years, the method for unitarizing nonunitary Dyson boson realizations of shell-model algebras has been both generalized and substantially simplified through the introduction of overtly group-theoretical methods. In this paper, these methods are applied to the boson-odd-particle realization of the algebra SO(2#nu#+1) for #nu# single-particle levels, adapted to the group chain SO(2#nu#+1) contains SO(2#nu#) contains U(#nu#), which Marshalek first derived by brute force summation of a Taylor expansion and later Okubo by a largely algebraic technique. (orig.).

198

Slide 1  

Wastenet

Sc.Technology & Policy (M.I.T., USA) M.Sc.

200

Comparative evaluation of /sup 99m/Tc GH, /sup 99m/TcO_4, and /sup 99m/Tc DTPA as brain imaging agents  

International Nuclear Information System (INIS)

The brain imaging properties of /sup 99m/Tc glucoheptonate, /sup 99m/Tc pertechnetate, and /sup 99m/Tc DPTA are compared. Results demonstrate that optimum images are obtained at 90, 180, and 180 min., for /sup 99m/Tc GH, /sup 99m/Tc DTPA, and /sup 99m/Tc pertechnetate, respectively. The former two images are not affected by prior bone imaging with /sup 99m/Tc pyrophosphate, while /sup 99m/Tc pertechnetate images are adversely affected. /sup 99m/Tc glucoheptonate appears to be the superior agent for brain imaging, followed by /sup 99m/Tc DTPA and /sup 99m/Tc pertechnetate.

201

Z-dependence of photon induced L_#alpha#/L_l X-ray intensity ratio in some elements 73 #<=# Z #<=# 92  

International Nuclear Information System (INIS)

L_#alpha#/L_l X-ray intensity ratios have been measured in elements Ta, W, Au, Hg, Tl, Pb, Bi, Th and U using L-shell photoionization by 60 keV photons. The present results are found to agree with the calculated values of Scofield within experimental uncertainties. (author).

1983-11-21

202

Tachyons in compact spaces  

Energy Technology Data Exchange (ETDEWEB)

We discuss condensations of closed string tachyons localized in compact spaces. Time evolution of an on-shell condensation is naturally related to the worldsheet RG flow. Some explicit tachyonic compactifications of Type II string theory is considered, and some of them are shown to decay into supersymmetric theories known as the little string theories.

2005-05-01

203

Surface photometry and the structure of elliptical galaxies  

International Nuclear Information System (INIS)

Surface photometry of bulges and elliptical galaxies is reviewed. The properties of cores and nuclei as revealed by improvements in seeing and the use of CCDs are examined, and newly discovered structural details such as dust, shells, and dynamical subsystems which show the importance of accretion events in galactic evolution are addressed. Improved constraints on galaxy formation resulting from better measurements of parameter scaling laws are discussed, and accurate measurements of departures from elliptical isophotes and of color gradients obtained with CCDs are considered.

204

Realistic level density calculation for heavy nuclei  

Energy Technology Data Exchange (ETDEWEB)

A microscopic calculation of the level density is performed, based on a combinatorial evaluation using a realistic single-particle level scheme. This calculation relies on a fast Monte Carlo algorithm, allowing to consider heavy nuclei (i.e., large shell model spaces) which could not be treated previously in combinatorial approaches. An exhaustive comparison of the predicted neutron s-wave resonance spacings with experimental data for a wide range of nuclei is presented.

1994-12-31

205

Perlinhibin, a Cysteine-, Histidine-, and Arginine-Rich Miniprotein from Abalone (Haliotis laevigata) Nacre, Inhibits In Vitro Calcium Carbonate Crystallization  

UK PubMed Central (United Kingdom)

We have isolated a 4.785 Da protein from the nacreous layer of the sea snail Haliotis laevigata (greenlip abalone) shell after demineralization with acetic acid. The sequence of 41...Full Text Available

2007-08-15

206

Pairing correlation effects on the electron-scattering form factor of the 1/sup +/ state at 3. 486 MeV in /sub 38//sup 88/Sr/sub 50/  

Energy Technology Data Exchange (ETDEWEB)

The electron scattering form factor for excitation of the 1/sup +/ state of /sup 88/Sr at 3.486 MeV has been calculated in the quasiparticle random phase approximation (QRPA). The disagreement between the data and restricted shell-model calculations can be explained in terms of the pairing correlations introduced by the QRPA; no ..delta..-h admixtures are required.

1985-06-06

207

Pairing correlation effects on the electron-scattering form factor of the 1"+ state at 3.486 MeV in _3_8"8"8Sr_5_0  

International Nuclear Information System (INIS)

The electron scattering form factor for excitation of the 1"+ state of "8"8Sr at 3.486 MeV has been calculated in the quasiparticle random phase approximation (QRPA). The disagreement between the data and restricted shell-model calculations can be explained in terms of the pairing correlations introduced by the QRPA; no #DELTA#-h admixtures are required. (orig.).

208

Options for passive containment cooling in next-generation nuclear plant designs  

International Nuclear Information System (INIS)

A design for passive cooling of large containment structures has progressed sufficiently to move forward into the detailed design stage necessary for plant construction. For such application, a safety analysis report has already been submitted to the US Nuclear Regulatory Commission. The design considers an annulus between the inner steel containment vessel and outer, thick-walled concrete shield building with chimney-like natural convection cooling driven only by a density gradient relative to the atmosphere. Air within the annulus is heated as internal containment temperature rises and heat is transferred through the steel containment shell. The resulting air density gradient between the annulus and the environment causes the heated air to rise, producing a natural convection flow through inlets in the shield building, past the steel shell, and out an exit chimney. Several options for enhancing passive heat removal of large containment ...

1993-11-01

209

On the nucleon decay of subbarrier single-particle states in soft spherical nuclei  

Energy Technology Data Exchange (ETDEWEB)

The nucleon decay of subbarrier single-particle states with large angular momentum and parity opposite to that of the shell in soft spherical nuclei is considered. It is shown that the reduced probabilities of the nucleon decay into the ground state (0{sup +}) and into the first excited (2{sup +}) state of the daughter nucleus have qualitatively different energy dependences. (orig.).

1991-06-20

210

On the nucleon decay of subbarrier single-particle states in soft spherical nuclei  

International Nuclear Information System (INIS)

The nucleon decay of subbarrier single-particle states with large angular momentum and parity opposite to that of the shell in soft spherical nuclei is considered. It is shown that the reduced probabilities of the nucleon decay into the ground state (0"+) and into the first excited (2"+) state of the daughter nucleus have qualitatively different energy dependences. (orig.).

211

On effective actions for the bosonic tachyon  

Energy Technology Data Exchange (ETDEWEB)

We extend the analysis of a previous paper to the bosonic case and find the one-derivative effective action valid in the vicinity of rolling tachyons with an energy not larger than that of the original D-brane. For on-shell tachyons rolling down the well-behaved side of the potential in this theory, the energy is conserved and the pressure eventually decreases exponentially. For tachyons rolling down the 'wrong' side, the pressure instead blows up in a finite time. (author)

2003-11-01

212

Nuclear matrix elements for the coherent -e conversion process  

Energy Technology Data Exchange (ETDEWEB)

The lepton flavor-violating coherent ( /sup -/, e/sup -/) conversion is investigated. Photonic and nonphotonic contributions arising in various gauge models are considered. The dependence of the conversion rate on the structure of the nucleus is given by the elastic form factors. These are obtained in the context of shell model taking into account finite-size effects or extracted from the electron scattering data whenever possible. The relevant branching ratios are studied throughout the periodic table.

1988-12-22

213

Nuclear level densities in self-consistent field approximation  

International Nuclear Information System (INIS)

The effect of two-body nature of the nuclear shell model potential on the recent numerical calculations of the nuclear level density has been examined. For the two most widely used single particle energy level schemes based on harmonic oscillator and Woods-Saxon potential, this effect is shown to significantly modify the excitation energy dependence of the level densities. (author).

1976-01-01

214

Large-Scale Computations Leading to a First-Principles Approach to Nuclear Structure  

Energy Technology Data Exchange (ETDEWEB)

We report on large-scale applications of the ab initio, no-core shell model with the primary goal of achieving an accurate description of nuclear structure from the fundamental inter-nucleon interactions. In particular, we show that realistic two-nucleon interactions are inadequate to describe the low-lying structure of {sup 10}B, and that realistic three-nucleon interactions are essential.

2003-08-18

215

K and L x-ray production cross sections excited by 14.00--34.16 MeV #alpha#-particle beams  

International Nuclear Information System (INIS)

K and L-shell x-ray production cross sections were measured using #alpha#-particle beams of 14.00 to 34.16 MeV. The K-shell measurements ranged from Z = 20 to Z = 50 and included Ca, Sc, Ti, V, Fe, Ni, Cu, Zn, Ga, Br, Rb, Sr, Y, Mo, Ag, In, and Sn while the L-shell measurements ranged from Z = 55 to Z = 92 and included Cs, Ba, Ce, Gd, Tm, Lu, Au, Pb, Th, and U. Thin metallic foils were used for the measurements and corrections for self-attenuation were negligible. A liquid nitrogen cooled Si(Li) detector and associated pulsed optical electronics were used in detecting x-rays. Absolute cross sections with an uncertainty of +-10 percent are presented for the elements measured. Also smoothed cross sections are presented which were generated by a three term polynomial fit of the experimental data points. By use of available fluorescence yields the K-shell data were converted to ionization cross sections and ...

216

Fabrication of Porous TiO2 Hollow Spheres and Their Application in Gas Sensing  

UK PubMed Central (United Kingdom)

In this work, porous TiO2 hollow spheres with an average diameter of 100 nm and shell thickness of 20 nm were synthesized by a facile hydrothermal method with NH4HCO3...Full Text Available

217

Experience with Aerosol Generation During Rotary Mode Core Sampling in the Hanford Single Shell Waste Tanks  

Energy Technology Data Exchange (ETDEWEB)

This document provides data on aerosol concentrations in tank headspaces, total mass of aerosols in the tank headspace, and mass of aerosols sent to the exhauster during rotary mode core sampling from November 1994 through June 1999. A decontamination factor for the RMCS exhauster filter housing is calculated based upon operational data and non-destructive assay.

2001-03-23

218

Experience with Aerosol Generation During Rotary Mode Core Sampling in the Hanford Single Shell Waste Tanks  

Energy Technology Data Exchange (ETDEWEB)

This document provides data on aerosol concentrations in tank head spaces, total mass of aerosols in the tank head space and mass of aerosols sent to the exhauster during Rotary Mode Core Sampling from November 1994 through June 1999. A decontamination factor for the RMCS exhauster filter housing is calculated based on operation data.

2000-01-24

219

Effect of the electron-electron coupling parameters on the superconducting transition temperature in the compounds with the A-15 structure  

International Nuclear Information System (INIS)

The electron structure of the A-15 compounds is studied by accounting for the Hubbard energy as the highest energy parameter. The conditions for the Cooper instability origination are obtained. The superconducting transition temperature dependence on the degree of filling the d- and p-shells of the transition and nontransition elements is determined. The relationship between the transition temperature and the energy jumpover along the chains, which allows comparison with the experiment, is established. Qualitative explanation of the Mattias empiric rules is presented

2000-09-01

220

EXCITATION OF ISOBARIC ANALOG STATES IN $sup 89$Y AND $sup 90$Zr  

Science.gov (United States)

The excitation of compound-nucleus resonances in Y/sup 89/ and Zr/sup 90/ by proton bombardment at 4 to 5.5 Mev of Sr/sup 88/ and Y/sup 89/, respectively, is reported. Shell-model corfigurations were used to interpret the results. (R.E.U.)

1964-02-24

221

Differences of the deformation parameter #beta# for 2"+_1 states of even-even spherical nuclei from electromagnetic excitation and proton scattering  

International Nuclear Information System (INIS)

Differences of the deformation parameters for the 2"+_1 states of even-even spherical nuclei extracted from electromagnetic excitation #beta#sup(em)_2 and from proton scattering #beta#sup(pp')_2 are discussed. It is found that the ratio #beta#sup(pp')_2/#beta#sup(em)_2 is equal to about unity and that there is a small isotope dependence for several incomplete shell nuclei. (orig.).

222

DOUBLE-SHELL TANK (DST) HYDROXIDE DEPLETION MODEL FOR CARBON DIOXIDE ABSORPTION  

International Nuclear Information System (INIS)

This document generates a supernatant hydroxide ion depletion model based on mechanistic principles. The carbon dioxide absorption mechanistic model is developed in this report. The report also benchmarks the model against historical tank supernatant hydroxide data and vapor space carbon dioxide data. A comparison of the newly generated mechanistic model with previously applied empirical hydroxide depletion equations is also performed.

2009-04-30

223

Analysis of titanium and zirconium in red mud with energy dispersive x-ray spectrometry  

Energy Technology Data Exchange (ETDEWEB)

An energy dispersive x-ray fluorescence technique was used for the determination of Titanium (Ti) and Zirconium (Zr) in red mud by using a standard addition method. An annular {sup 241}Am source is employed for excitation of K shells of elements. 13 refs., 2 figs., 1 tab.

1996-11-01

224

Nuclear structure of light Ca and heavy Cr isotopes  

Energy Technology Data Exchange (ETDEWEB)

In the present thesis, the shell structure in exotic nuclei has been investigated. The focus of the work was on finding new experimental data in neutron-rich Cr and proton-rich Ca isotopes. The investigation of light Ca isotopes concentrated on the nucleus {sup 36}Ca which was produced in a knockout reaction from a radioactive {sup 37}Ca beam. For {sup 36}Ca, the excitation energy of the first 2{sup +} state has been measured for the first time. Furthermore, momentum distributions were analyzed using a Monte-Carlo simulation of the knockout reaction. This analysis yielded the contributions of neutrons from individual orbitals to the total knockout cross section. In principle, these may be used to calculate spectroscopic factors, but such a calculation is hampered by difficulties of present knockout-reaction models in predicting precise single-particle cross sections. The measured branching ratio to the ground and excited states, on the other hand, is close to the ...

2007-07-01

225

lua3456m.248  

Science.gov (United States)

xG3V 5d(+ sd`V jPLzT mZzt ~ 1VO W!~O 91mo Uq8m Cvfn\\ y&-. fU-m zQf`T F:P_= ^. ...

226

lla3282m.165  

Science.gov (United States)

... {lwvpqqkurxmtzoy }sprysy xmrv t`okbg\\

227

New measurement of excitation functions for (d,x) reactions on {sup nat}Mo with special regard to the formation of {sup 95m}Tc, {sup 96m+g}Tc, {sup 99m}Tc and {sup 99}Mo  

Energy Technology Data Exchange (ETDEWEB)

Cross-sections for the deuteron-induced reactions on natural molybdenum leading to {sup 93m}Tc, {sup 93m+g}Tc, {sup 94}Tc, {sup 94m}Tc, {sup 95}Tc, {sup 95m}Tc, {sup 96m+g}Tc, {sup 99m}Tc, {sup 99}Mo, {sup 101}Mo, {sup 90m+g}Nb, {sup 92m}Nb, {sup 95}Nb and {sup 89m+g}Zr were measured in the energy range 3.0-19.6 MeV on the cyclotron U-120 M in the Institute of Nuclear Physics AS CR. Special attention was paid to excitation functions and thick target yields for the formation of {sup 95m}Tc, a suitable tracer for {sup 99}Tc, of {sup 96m+g}Tc, which might be used as a beam monitor, and of {sup 99m}Tc and {sup 99}Mo, the most widespread radionuclide generator pair in nuclear medicine. If appropriate, obtained data are ...

2010-12-15

228

New measurement of excitation functions for (d,x) reactions on "n"a"tMo with special regard to the formation of "9"5"mTc, "9"6"m"+"gTc, "9"9"mTc and "9"9Mo  

International Nuclear Information System (INIS)

Cross-sections for the deuteron-induced reactions on natural molybdenum leading to "9"3"mTc, "9"3"m"+"gTc, "9"4Tc, "9"4"mTc, "9"5Tc, "9"5"mTc, "9"6"m"+"gTc, "9"9"mTc, "9"9Mo, "1"0"1Mo, "9"0"m"+"gNb, "9"2"mNb, "9"5Nb and "8"9"m"+"gZr were measured in the energy range 3.0-19.6 MeV on the cyclotron U-120 M in the Institute of Nuclear Physics AS CR. Special attention was paid to excitation functions and thick target yields for the formation of "9"5"mTc, a suitable tracer for "9"9Tc, of "9"6"m"+"gTc, which might be used as a beam monitor, and of "9"9"mTc and "9"9Mo, the most widespread radionuclide generator pair in nuclear medicine. If appropriate, obtained data are compared with the heretofore published cross-sections.

2010-12-01

229

M protein (M1) of influenza virus: antigenic analysis and intracellular localization with monoclonal antibodies.  

UK PubMed Central (United Kingdom)

A panel of 16 monoclonal antibodies recognizing M protein (M1) of influenza virus was generated. Competition analyses resulted in localization of 14 monoclonal antibodies to three antigenic sites. Three...Full Text Available

1989-09-01

231

The toughness amplification map of poly(vinyl chloride) and its cellulose acetate-compatibilized starch alloys containing core/shell rubber particles: Possible transition to super-toughening  

British Library Electronic Table of Contents (United Kingdom)

Abstract Toughening amplification of the neat poly(vinyl chloride) (PVC) and its reinforced version containing 25 phr of the cellulose acetate (CA)-compatibilized starch using methyl methacrylate-butadiene-styrene (MBS) core-shell particles was studied. The room temperature measured impact strength of the PVC showed mild increase up to 10 wt % with the addition of MBS particles. Then, the toughness enhanced discontinuously to super-tough plateau regime. The room temperature measured impact strength of PVC containing 20 phr of MBS particles, however, was reduced by as much as 95% when it was filled with 25 phr of the CA-compatibilized starch. In addition, the brittle-ductile transition (BDT) of the toughened PVC increased from 0 to 60 C because of its reinforcement, even though the matrix n...

2011-01-01

232

The importance of turbulence modelling in the design of a novel delivery system for a single-belt steel casting process  

Energy Technology Data Exchange (ETDEWEB)

In this work, a comprehensive model including heat transfer, fluid flow and solidification was used to evaluate the performance of a novel delivery system for a single-belt steel casting process. This near-net-shape casting, although still in development, is one of the most promising routes for casting of low-carbon steel in large scale. This paper focuses on the performance of a low-Re {kappa}-{epsilon} model that was employed to simulate the three-dimensional turbulent flows fully-coupled with heat transfer and macroscopic solidification. Simulations were run for the intended conditions of caster operation, and the results obtained with the {kappa}-{epsilon} were compared with the results obtained with an ad hoc viscosity model, where the molecular viscosity was boosted 100 times, uniformly throughout the computational domain. A semi-analytical solution was employed for validating the models and the results showed that the ad hoc viscosity model overestimated the thickness of the ...

2000-01-01

233

The Effect of Heat Treatment and Mechanical Polishing on Nitinol Stent  

Energy Technology Data Exchange (ETDEWEB)

To understand the effect of heat treatment and mechanical polishing of a Nitinol wire on the chemical composition and physical morphology of the wire surface. Stents with a diameter of 1.0 cm, length of 8-10 cm, and composed of a Nitinol wire, were heat-treated at 500 .deg. C for 30 minutes, and mechanically polished with walnut shell granules. The wire surface morphology was studied with both an optical and a scanning electron microscope (SEM). In addition, an elemental analysis was performed by Energy Dispersive X-ray spectroscopy (EDX). Long microcracks along the wire direction and short microcracks across the wire were observed by SEM from the raw Nitinol wire. Upon heat treatment, the color of the wire turned blue, and Na, K, Cl, Si, Al atoms were seen from the EDX of the heat treated wire, which were absent in the original wire. The microcracks disappeared with the mechanical polishing, and the Na, K, Cl, Si, Al atoms all disappeared after the mechanical ...

2009-09-15

234

Lattice relaxation around impurity atoms in semiconductors - arsenic in silicon - a comparison between experiment and theory  

International Nuclear Information System (INIS)

We have measured the lattice relaxation around As in Si at a homogeneous As concentration of 4x10"1"8 cm"-"3 by EXAFS spectroscopy. From the absorption spectra, distances up to the 4th shell could be extracted. A sizeable misfit due to an increased distance is only observed for the 1st shell. Complementing our experimental work we have performed ab initio calculations based on the density functional theory with the WIEN97 package which uses the linearised augmented plane wave method and with the FHI96md program which uses first-principles pseudo-potentials and a plane wave basis set to investigate the size dependence of the super-cells constructed around one substitutional As atom. The calculations yielded good agreement with our EXAFS experiment so that the determined relaxations can be used as a solid basis for further interpretations of derived parameters such as hyperfine interaction parameters in defect complexes.

2003-01-01

235

Internal stresses analysis in telectroformed nickel shells for thermoplastics injection mold core (rapid tooling); Analisis de las tensiones internas en las cascaras de niquel electroconformadas que se utilizan como inserto de un molde de inyeccion de termoplasticos (rapid tooling)  

Energy Technology Data Exchange (ETDEWEB)

This study deals with a research field started at the LFI (Laboratorio de Fabricacion Integrada) of the ULPGC (Universidad de Las Palmas de Gran Canaria). Its aim is to analyse and propose improvements in the electroformed nickel cores manufacture. The main application of these cores is to be used as plastic injection molds. It has been considered an important part of this study taking under consideration internal stresses that appear in the nickel electroformed core. These stresses play a determinant role towards reaching a dimensional and resistant quality standard of the shells, which will be later transformed into cores. The investigation includes not only a theoretic study but also an experimental one. the testing method has the remarkable advantage of a wide industrial application because of its simplicity, low cost and reproducibility of the electrolytic bath actual conditions. (Author) 7 refs.

2005-07-01

236

High spin states of some nuclei around the N=Z=28 double closed shell  

Energy Technology Data Exchange (ETDEWEB)

A spectroscopic study is performed for high spin states of {sup 55}Fe, {sup 55}Co and {sup 57}Ni. To populate the investigated residues with a relevant cross section, the fusion evaporation reactions of {sup 30}Si({sup 28}Si, 2pn){sup 55}Fe, {sup 30}Si({sup 28}Si, 2pn){sup 55}Co and {sup 4}He({sup 54}Fe, n){sup 57}Ni were chosen. To identify the new {gamma} transitions and to build the energy level schemes, {gamma}-{gamma} coincidence techniques together with excitation functions were employed. Angular distributions and {gamma}-{gamma} angular correlations allowed us to assign the spin values of the nuclear states. The previous level scheme of {sup 55}Fe is extended into the region between 6.5-11 MeV of excitation energy, up to spin 27/2, while the yrast decay pathos of {sup 57}Ni and {sup 55}Co are reported here for the first time. Experimental data are fairly well reproduced by Glaudemans' shell model calculations. (orig.).

1989-12-01

237

High spin states of some nuclei around the N=Z=28 double closed shell  

International Nuclear Information System (INIS)

A spectroscopic study is performed for high spin states of "5"5Fe, "5"5Co and "5"7Ni. To populate the investigated residues with a relevant cross section, the fusion evaporation reactions of "3"0Si("2"8Si, 2pn)"5"5Fe, "3"0Si("2"8Si, 2pn)"5"5Co and "4He("5"4Fe, n)"5"7Ni were chosen. To identify the new #gamma# transitions and to build the energy level schemes, #gamma#-#gamma# coincidence techniques together with excitation functions were employed. Angular distributions and #gamma#-#gamma# angular correlations allowed us to assign the spin values of the nuclear states. The previous level scheme of "5"5Fe is extended into the region between 6.5-11 MeV of excitation energy, up to spin 27/2, while the yrast decay pathos of "5"7Ni and "5"5Co are reported here for the first time. Experimental data are fairly well reproduced by Glaudemans' shell model calculations. (orig.).

1989-01-01

238

Fuel bundle geometry and composition influence on coolant void reactivity reduction in ACR and CANDU reactors  

International Nuclear Information System (INIS)

It is very well known that the CANDU reactor has positive Coolant Void Reactivity (CVR), which is most important criticisms about CANDU. The most recent innovations based on using a thin absorbent Hafnium shell in the central bundle element were successfully been applied to the Advanced CANDU Reactor (ACR) project. The paper's objective is to analyze elementary lattice cell effects in applying such methods to reduce the CVR. Three basic fuel designs in their corresponding geometries were chosen to be compared: the ACR-1000TM, the RU-43 (developed in INR Pitesti) and the standard CANDU fuel. The bundle geometry influence on void effect was also evaluated. The WIMS calculations proved the Hafnium absorber suitability (in the latest 'shell design') to achieve the negative CVR target with great accuracy for the ACR-1000 fuel bundle design than for the other two projects. (authors)

2009-05-27

239

Evaluation of small-angle neutron scattering curves of unilamellar phosphatidylcholine liposomes using a multi shell model of bilayer neutron scattering length density  

International Nuclear Information System (INIS)

Computer simulated small-angle neutron scattering curves of spherical poly disperse extruded unilamellar liposomes from saturated 1,2-diacylphosphatidylcholines in the aqueous phase are evaluated by using a multi shell model, which divides the lipid bilayer of liposomes into the polar head group region, and the nonpolar hydrocarbon region consisting of the chains of methylene groups and of the region of methyl groups. In the each of these regions, the coherent neutron scattering length density is supposed to by homogeneous. The evaluation is based on obtaining of radius of gyration from Kratky-Porod plot of small-angle neutron scattering data in the Guinier region of small scattering vector values. From radii of gyration obtained at several different molar fractions N_D_2_O/(N_D-2_O + N_H_2_O) in the aqueous phase (contrasts) and independent volumetric data, the lipid surface area A_L (or the bilayer thickness d_L) and the number of water molecules N_L penetrated ...

2000-12-15

240

Evaluation of scaling correlations for mobilization of double-shell tank waste  

Energy Technology Data Exchange (ETDEWEB)

In this report, we have examined some of the fundamental mechanisms expected to be at work during mobilization of the waste within the double-shell tanks at Hanford. The motivation stems from the idea that in order to properly apply correlations derived from scaled tests, one would have to ensure that appropriate scaling laws are utilized. Further, in the process of delineating the controlling mechanisms during mobilization, the currently used computational codes are being validated and strengthened based on these findings. Experiments were performed at 1/50-scale, different from what had been performed in the previous fiscal years (i.e., 1/12- and 1/25-scale). It was anticipated that if the current empirical correlations are to work, they should be scale invariant. The current results showed that linear scaling between the 1/25-scale and 1/50-scale correlations do not work well. Several mechanisms were examined in the scaled tests which might have contributed to ...

1997-09-01

241

Electron diodes and cavity design for the new 4-MeV injector of the recirculating linear accelerator (RLA)  

International Nuclear Information System (INIS)

The authors have designed and constructed four types of electron-beam diodes for the new 4-MV RLA injector: a non-immersed foilless diode, a magnetically immersed foilless diode, a foil diode and an ion-focused foilless diode, They are tailored to fit the new injector cavity. The design goals were to produce high quality 10-kA to 20-kA electron beams with a #beta# perpendicular smaller than 0.2 and a beam radius of the order of 2 cm. These beams will be matched to the RLA IFR channel so #beta# perpendicular must be equal to or smaller than the square root of the ratio of the beam current versus Alfven current for f_e = 1. A reentrant anode geometry was selected for the injector cavity design, because it offers substantial savings on the required amount of feromagnetic cores. The inner radius of the outside shell, now only 30 cm, would have been twice as large (60 cm) if a coaxial non-reentrant geometry had been adopted. The shape of the anode and cathode electrodes ...

1991-03-01

242

Application of realistic meson-exchange forces in the broken-pair model  

Energy Technology Data Exchange (ETDEWEB)

A G-matrix, derived from a meson-exchange potential in nuclear matter, is applied to finite, semi-magic nuclei. For the open shell the broken-pair model, which can accommodate many single-particle levels, is used. The excitations of the closed shell are treated as particle-hole states. Energy spectra and electromagnetic transition densities are calculated for /sup 88/Sr and /sup 58/Ni. The energies of the non-collective states are well described. Pairing correlations in the ground state have almost the correct strength in a multishell model space. To improve the energies of the collective 2/sup +/ and 3/sup -/ states the inclusion of core-polarisation effects in the force is required. Transition charge densities for collective states become strongly surface-peaked by core-polarisation effects, as is observed in experiments. The effects of pairing correlations and core polarisation on the magnetic form factor of the 3.486 MeV 1/sup +/ state in ...

1985-03-11

243

Application of realistic meson-exchange forces in the broken-pair model  

International Nuclear Information System (INIS)

A G-matrix, derived from a meson-exchange potential in nuclear matter, is applied to finite, semi-magic nuclei. For the open shell the broken-pair model, which can accommodate many single-particle levels, is used. The excitations of the closed shell are treated as particle-hole states. Energy spectra and electromagnetic transition densities are calculated for "8"8Sr and "5"8Ni. The energies of the non-collective states are well described. Pairing correlations in the ground state have almost the correct strength in a multishell model space. To improve the energies of the collective 2"+ and 3"- states the inclusion of core-polarisation effects in the force is required. Transition charge densities for collective states become strongly surface-peaked by core-polarisation effects, as is observed in experiments. The effects of pairing correlations and core polarisation on the magnetic form factor of the 3.486 MeV 1"+ state in "8"8Sr are found to be ...

244

lla4846m.146  

Science.gov (United States)

... {njfdkipzkn}m hmplbiib|ekbhbik phiekknlokrpokjk qwqslqupvrv xmrv qljqsolsh ihhlxf_kh`gilimhddgofmicgfghbb`\\^a__d`mhf`indjliz lthpfopnsoonlthjphmoggfpclq ...

245

Using the Am9511 arithmetic processing unit with the Motorola M6800 microprocessor  

CERN Document Server

Using the Am9511 arithmetic processing unit with the Motorola M6800 microprocessor

1979-01-01

246

The virtual fast-ion loss detector  

International Nuclear Information System (INIS)

English 2009 p. 79 Ukraine Brudgam, M. Lauber, Ph. Garcia Munoz, M.

2009-09-21

247

The distribution of mass-to-light ratio with radius in M31 and M33  

International Nuclear Information System (INIS)

1974. Netherlands Baldwin, JE Cambridge Univ. (UK). Cavendish Lab. Reidel.;

248

Satellite imagery as verification tool for safeguards  

International Nuclear Information System (INIS)

... Formosat (Taiwan, China) 2m WorldView-1 (US) 0.5m The SIAU is using

2009-02-03

249

CHLOROPICRIN LEAKAGE TEST OF THE M17 PROTECTIVE ...  

Science.gov (United States)

... CHLOROPICRIN LEAKAGE TEST Of THE M17 PPRDOtCTIVE MASK EQUIPPED WITH DRINKING AND RESUSCITATION DEVICIS WORN BY ...

1965-10-01

250

4 maj 2009  

Wastenet

, Rinaldi, M., Fokkens, B.(eds.).IVth ECRR International ..., Rinaldi, M., Fokkens, B.(eds.).IVth ECRR International

251

np-nh bands in the N=28 isotones  

CERN Document Server

The existence of n-particle n-hole deformed yrare bands in the N=28 isotones is explored using full pf-shell diagonalizations and the Lanczos Strength Function method. We find different 2p-2h and 4p-4h collective bands that, when allowed to mix, more often disappear. Only the 2p-2h yrare band in Cr-52 and the 4p-4h yrare band in Ni-56 survive, and only in this latter case, due to the reduced density of 2p-2h states, can the band be seen as a gamma-cascade.

2002-01-01

252

Three-dimensional discrete ordinates radiation transport calculations of neutron fluxes for beginning-of-cycle at several pressure vessel surveillance positions in the high flux isotope reactor  

Energy Technology Data Exchange (ETDEWEB)

The objective of this research was to determine improved thermal, epithermal, and fast fluxes and several responses at mechanical test surveillance location keys 2, 4, 5, and 7 of the pressure vessel of the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR) for the beginning of the fuel cycle. The purpose of the research was to provide essential flux data in support of radiation embrittlement studies of the pressure vessel shell and beam tubes at some of the important locations.

1993-11-01

253

Symmetries in nuclei near the centre of the f{sub 7/2} shell  

Energy Technology Data Exchange (ETDEWEB)

High-spin states in the mirror pair nuclei {sup 49}Cr and {sup 49}Mn and their cross-conjugate partners, the mirror pair {sup 47}V and {sup 47}Cr have been investigated using experimental {gamma}-ray spectroscopic techniques. The combination of high-efficiency EUROBALL cluster Germanium detectors and clean exit-channel gating afforded by a 31-element silicon ball used in conjunction with a 15-detector neutron wall allowed a revision and extension to the energy level schemes of all four nuclei up to J{sup {pi}}=31{sup -}/2. The difference in excitation energy between states of equivalent spin in the parent nucleus and its analogue partner have thus been established for both mirror pairs up to the f{sub 7/2}-shell band terminating state for the first time. This difference is assumed to be due almost entirely to the Coulomb effect and is therefore called the Coulomb energy difference (CED). The variation in the CED with spin has been interpreted as reflecting the ...

1998-10-01

254

Spectroscopy of neutron-rich Fe isotopes populated in the "6"4Ni+"2"3"8U reaction  

International Nuclear Information System (INIS)

The neutron-rich Fe isotopes from A=61 to 66 were studied through multinucleon transfer reactions by bombarding a "2"3"8U target with a 400 MeV "6"4Ni beam. Unambiguous identification of prompt #gamma# rays belonging to each nucleus was achieved using coincidence relationships with the ions detected in a high-acceptance magnetic spectrometer. The new data extend our knowledge of the level structure of Fe isotopes, which is discussed in terms of the systematics of the region and compared with large-scale shell-model calculations.

2007-09-01

255

On-shell S-matrix and tachyonic effective actions  

Energy Technology Data Exchange (ETDEWEB)

We evaluate various disk level four-point functions involving the massless scalar and tachyon vertex operators in the presence of background B-flux in superstring theory. By studying these amplitudes in specific limits, we find couplings of two scalars with two tachyons, and couplings of four tachyons on the world-volume of non-BPS D-branes of superstring theory. They are fully consistent with the non-commutative tachyonic Dirac-Born-Infeld effective action. They also fix the coefficient of T{sup 4} term in the expansion of the tachyon potential around its maximum.

2002-12-23

256

Low-energy fission of nuclei lighter than Hg  

International Nuclear Information System (INIS)

The mass and energy distributions for low-energy p- and alpha-particle induced fission of "1"8"7","1"8"8Ir and "1"9"5Au and "3He-induced fission of sufficiently heated "1"8"8Ir and "1"9"4Au have been measured with use of fast spectrometer of complementary fragments. From Au to Ir, the shape of the mass distributions undergoes substantial changes related to specific dependence of the saddle shell corrections on A and Z fissioning nuclei. The results are compared with theoretical predictions.

257

From biomass to producer gas  

Energy Technology Data Exchange (ETDEWEB)

This article outlines the use of gasifiers during World War II and how, with soaring fuel prices, producer gas may provide an alternate energy path for agribusiness and farms today. In the last few years, the University of California has become a focus of producer gas research in the US. Biomass fuels used include crushed walnut shells, fruit pits, cereal straw and corn cobs. Particle size, moisture content and slagging create problems and the right kind of gas producer must be used to obtain reliable conversion to producer gas.

1980-09-08

258

Experiments to investigate the effects of radiative cooling on plasma jet collimation  

CERN Document Server

Preliminary experiments have been performed to investigate the effects of radiative cooling on plasma jets. Thin (3 um - 5 um) conical shells were irradiated with an intense laser, driving jets with velocities > 100 km/s. Through use of different target materials - aluminium, copper and gold - the degree of radiative losses was altered, and their importance for jet collimation investigated. A number of temporally resoved optical diagnostics was used, providing information about the jet evolution. Gold jets were seen to be narrower than those from copper targets, while aluminium targets produced the least collimated flows.

2010-01-01

259

Electromagnetic decay properties of multiparticle-hole states in neutron deficient Mo and Tc isotopes  

Energy Technology Data Exchange (ETDEWEB)

Neutron deficient nuclei with mass numbers A {approx} 90 and 40 {<=} Z {<=} 44 have been studied making use of the Osiris and Nordball spectrometers. The high spin states of these nuclei and their electromagnetic decay properties are compared to shell model calculations based on the core {sup 88}Sr and using different parametrizations of the residual interaction. The dependence of the mean square deviations of experimental and theoretical level energies, branching ratios, and transition probabilities on the neutron numbers N = 46-50 and the validity of seniority as a good quantum number are discussed. (orig.).

1995-12-31

260

E2 transition densities and proton shell structure in /sup 88/Sr, /sup 89/Y, and /sup 90/Zr  

Energy Technology Data Exchange (ETDEWEB)

Electron scattering data have been used to obtain transition charge densities for the low-lying E2 transitions in /sup 88/Sr, /sup 89/Y, and /sup 90/Zr. These charge densities show a characteristic shape indicative of their microscopic constituency, modified by core-polarization effects. A good description of transitions in the even-even nuclei is obtained by using the measured single-particle transitions in /sup 89/Y as effective densities. .ID LV2086 .PG 19 22

1983-01-03

261

Dynamic response of pipelines buried in back-filled trenches  

Energy Technology Data Exchange (ETDEWEB)

Dynamic response of pipelines buried in a back-filled rectangular trench in a semi-infinite medium has been investigated. The pipelines are modeled as long cylindrical shells of small thickness. By using the boundary integral representation and finite element method, we have studied the three-dimensional response to account for either pane P or SV wave incident at an arbitrary angle to the pipe-axis. In this paper numerical results are presented for the normal displacements, displacements along pipe-axis, and the hoop stresses in the pipe wall. It is shown that the response depends critically on the back-filled material as well as on the directions of propagation of the incident waves.

1991-08-01

262

Confrontation between stellar pulsation and evolution; Proceedings of the Conference (ASP Series, Vol. 11), Bologna, Italy, May 28-31, 1990  

International Nuclear Information System (INIS)

Attention is given to the folowing topics: population I and II variable stars; LP variables, the sun, and mass determination; and predegenerate and degenerate variables. Particular papers are presented on alternative evolutionary approaches to the absolute magnitude of the RR Lyrae variables; the evolution of the Cepheid stars; nonradial pulsations in rapidly rotating Delta Scuti stars; dynamical models of dust shells around Mira variables; and pulsations of central stars of planetary nebulae.

1990-05-28

263

Collectivity at N=40 in neutron-rich "6"4Cr  

International Nuclear Information System (INIS)

"9Be-induced inelastic scattering of "6"2","6"4","6"6Fe and "6"0","6"2","6"4Cr was performed at intermediate beam energies. Excited states in "6"4Cr were measured for the first time. Energies and population patterns of excited states in these neutron-rich Fe and Cr nuclei are compared and interpreted in the framework of large-scale shell-model calculations in different model spaces. Evidence for increased collectivity and for distinct structural changes between the neighboring Fe and Cr isotopic chains near N=40 is presented.

2010-05-01

264

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds  

Energy Technology Data Exchange (ETDEWEB)

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds were studied by electron and proton bombardments. L{sub {gamma}1} X-rays which involve transition of 4d electrons of the valence shell were found to be sensitive to the chemical environment. The L{sub {gamma}1}/L{sub {beta}1} X-ray intensity ratio increased with an increase of the 4d electron occupation of niobium or molybdenum in niobium or molybdenum compounds, showing that the chemical effects can be ascribed to the 4d electron behavior of the metallic atom in its compounds. (orig.).

1990-12-20

265

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds  

International Nuclear Information System (INIS)

Chemical effects of L X-ray intensity ratios in niobium and molybdenum compounds were studied by electron and proton bombardments. L_#gamma#_1 X-rays which involve transition of 4d electrons of the valence shell were found to be sensitive to the chemical environment. The L_#gamma#_1/L_#beta#_1 X-ray intensity ratio increased with an increase of the 4d electron occupation of niobium or molybdenum in niobium or molybdenum compounds, showing that the chemical effects can be ascribed to the 4d electron behavior of the metallic atom in its compounds. (orig.).

1990-12-01

266

Analysis of a bayonet tube heat exchanger  

Energy Technology Data Exchange (ETDEWEB)

This paper details the design, construction and testing of a bayonet tube heat exchanger for use in the process industry and potentially as part of an externally fired combined cycle. Detailed analysis of the system has been undertaken, in particular on the tube side. The data is reported in terms of temperature, pressure, heat gain and heat exchanger effectiveness, over a range of Reynolds numbers and shell side mixture ratios. Much of the heat gained by the tubes is in the annular flow of the bayonet tube. Overall the effectiveness of this system could exceed 70%. (Author)

2001-01-01

267

A measurement of the cross section for electron impact ionization of Ar"2"+, Kr"2"+ and Xe"2"+  

International Nuclear Information System (INIS)

The crossed electron-ion beams technique was used to measure absolute cross sections for single ionization of Ar"2"+, Kr"2"+ and Xe"2"+ ions at electron energies ranging from threshold to 2000 eV. In contrast to some previous measurements, the metastable contents of the ion beams were small even in the case of Xe"2"+. All measured cross section curves show significant contributions from excitation-autoionization and possibly direct ionization of inner-shell electrons. There is evidence for resonance-excitation-double-autoionization in the case of Xe"2"+. (author).

268

Spectroscopy of /sup 87,88,89/Sr with (n,. gamma. ) and (d,p) reactions  

Science.gov (United States)

Over the recent years the nuclear structure around the N = 50 shell closure, which is very pronounced in the strontium and zirconium isotopes, has been the subject of extensive experimental and theoretical work. On the proton side Z = 38 and Z = 40 provide fairly closed sub-shells. In the strontium isotopes the lg/sub 9/2/ neutron shell is closed at /sup 88/Sr, supplying relatively pure neutron-hole and neutron-particle states with large spectroscopic factors in /sup 87/Sr and /sup 89/Sr, as well as core-coupled states. The mass region is thus ideally suited to examine the transition from a correlated to an uncorrelated (chaotic.) excitational behavior. These two types are characterized e.g. by the density of excited states, the transition strengths, and the spectroscopic factors observed in transfer reactions. We conducted (n,..gamma..) and (d,p) reactions leading to /sup 87,88,89/Sr in addition to /sup 88/Sr(d,t)/sup ...

1988-01-01

269

Spectroscopy of /sup 87,88,89/Sr with (n,#gamma#) and (d,p) reactions  

International Nuclear Information System (INIS)

Over the recent years the nuclear structure around the N = 50 shell closure, which is very pronounced in the strontium and zirconium isotopes, has been the subject of extensive experimental and theoretical work. On the proton side Z = 38 and Z = 40 provide fairly closed sub-shells. In the strontium isotopes the lg/sub 9/2/ neutron shell is closed at "8"8Sr, supplying relatively pure neutron-hole and neutron-particle states with large spectroscopic factors in "8"7Sr and "8"9Sr, as well as core-coupled states. The mass region is thus ideally suited to examine the transition from a correlated to an uncorrelated (chaotic?) excitational behavior. These two types are characterized e.g. by the density of excited states, the transition strengths, and the spectroscopic factors observed in transfer reactions. We conducted (n,#gamma#) and (d,p) reactions leading to /sup 87,88,89/Sr in addition to "8"8Sr(d,t)"8"7Sr and 24 keV neutron ...

1988-04-24

270

Combustion characteristics of fuel droplets with addition of nano and micron-sized aluminum particles  

Energy Technology Data Exchange (ETDEWEB)

The burning characteristics of fuel droplets containing nano and micron-sized aluminum particles were investigated. Particle size, surfactant concentration, and the type of base fluid were varied. In general, nanosuspensions can last much longer than micron suspensions, and ethanol-based fuels were found to achieve much better suspension than n-decane-based fuels. Five distinctive stages (preheating and ignition, classical combustion, microexplosion, surfactant flame, and aluminum droplet flame) were identified for an n-decane/nano-Al droplet, while only the first three stages occurred for an n-decane/micron-Al droplet. For the same solid loading rate and surfactant concentration, the disruption and microexplosion behavior of the micron suspension occurred later with much stronger intensity. The intense droplet fragmentation was accompanied by shell rupture, which caused a massive explosion of particles, and most of them were burned during this event. On the ...

2011-02-15

271

TRACG post-test analysis of PANDA tests M3 and M2  

International Nuclear Information System (INIS)

The author describes the results of post-test analyses of PANDA transient (M-series) tests M2 and M3. The purpose of the PANDA post-test analysis activity is to demonstrate that TRACG is applicable for the calculation of long-term SBWR containment response to a LOCA. Comparisons between TRACG predictions and test measurements are presented and discussed in the dual context of what the test results show and the capability of TRACG to predict their key features

1997-04-14

272

A nuclear engine design with {sup 242m}Am as a nuclear fuel  

Energy Technology Data Exchange (ETDEWEB)

A preliminary design for a nuclear engine is presented. The engine is based on the nuclear heating of a gas composed of H{sub 2} and {sup 242m}Am as a nuclear fuel. This engine has an initial volume of 0.135 m{sup 3} and at 64 MPa the critical mass is 0.228 kg. The simplicity {sup 242m}Am of the engine design might compensate for the use of rare nuclear fuel, such as {sup 242m}Am.

2000-01-01

273

Site-specific modification of albumin by free radicals. Reaction with copper(II) and ascorbate.  

UK PubMed Central (United Kingdom)

Exposure of albumin to Cu(II) (10-100 microM) and ascorbate (0.1-2 mM) results in extensive molecular modifications, indicated by decreased fluorescence and chain breaks. The rate of utilization of...Full Text Available

1986-06-01

274

STR References 3001-3250  

Science.gov (United States)

Journal of Human Genetics. 82: 873-882. 3134. Schulz, I., Schneider, P. M., Olek, K, Rothschild, M. A., and Tsokos, M. (2006) Examination of Postmortem Animal Interference to Human...

2009-03-16

275

Potential of mTOR inhibitors for the treatment of subependymal giant cell astrocytomas in tuberous sclerosis complex  

UK PubMed Central (United Kingdom)

Rapamycin inhibits the mTOR (target of rapamycin) pathway and extends lifespan in multiple species. The tuberous sclerosis complex (TSC) protein is a negative regulator of mTOR. In humans, loss of the...Full Text Available

276

Molecular and Kinetic Comparison of the Novel Extended-Spectrum ?-Lactamases CTX-M-25 and CTX-M-26  

UK PubMed Central (United Kingdom)

CTX-M-25 is a novel extended-spectrum β-lactamase isolated from a single Canadian Escherichia coli isolate. Susceptibility testing demonstrated that this enzyme confers resistance...Full Text Available

2004-12-01

277

Limitations of Tc99m-MIBI-SPECT Imaging Scans in Persistent Primary Hyperparathyroidism  

UK PubMed Central (United Kingdom)

BackgroundIn primary hyperparathyroidism (PHPT) the predictive value of technetium 99m sestamibi single emission computed tomography (Tc99m-MIBI-SPECT) for localizing pathological...Full Text Available

2011-01-01

278

Influence of hormones and medium components on expression of dipyranocoumarins in cell suspension cultures of Calophyllum inophyllum L.  

British Library Electronic Table of Contents (United Kingdom)

Cell suspension cultures were initiated separately from leaf and nodal/internodal calluses for the study of influence of hormones and medium components on biomass growth and expression of dipyranocoumarins. Highest 6.2 times biomass was enhanced in suspension cultures of nodal/internodal callus supplemented with threefold total sulphate. Picloram 8.28mM along with BAP 8.88mM enhanced 295.05 times inophyllum A in suspension cultures of leaf callus whereas IBA 14.70mM along with BAP 4.44mM in suspension cultures of leaf callus enhanced 1065 times inophyllum B. IBA 4.90mM alone in suspension cultures of nodal/internodal callus enhanced maximum 616 times inophyllum C. Only IBA 9.80mM in suspension cultures of leaf callus enhanced 23.22 times inophyllum P. Variation in nitrate and sulphate had ...

2009-01-01

279

In vitro analysis of nuclear mRNA export using molecular beacons for target detection  

UK PubMed Central (United Kingdom)

A detailed molecular characterization of nuclear mRNA export will require an in vitro system, allowing a biochemical reconstitution of transport. To this end, an mRNA export assay has...Full Text Available

2003-06-01

280

Growth-Phase-Dependent Expression of Virulence Factors in an M1T1 Clinical Isolate of Streptococcus pyogenes  

UK PubMed Central (United Kingdom)

The effect of growth phase on expression of virulence-associated factors was studied by Northern hybridization in an M1T1 clinical isolate of Streptococcus pyogenes. Expression of M...Full Text Available

1999-10-01

281

Excretion of para-aminohippurate in the isolated perfused rat kidney: net secretion and net reabsorption.  

UK PubMed Central (United Kingdom)

1. The excretion of para-aminohippurate (PAH) in the isolated perfused rat kidney was examined over a wide range of perfusate PAH concentrations (15 microM to 6 mM). PAH excretion increased steadily...Full Text Available

1988-03-01

282

Complexes of hepatitis B surface antigen and immunoglobulin M in the sera of patients with hepatitis B virus infection.  

UK PubMed Central (United Kingdom)

Hepatitis B surface antigen (HBsAg) bound to immunoglobulin M (IgM) was detected in sera of HBsAg carriers by a radioimmunoassay based on selective absorption of the immunoglobulin on a solid phase...Full Text Available

1983-09-01

283

CTX-M ?-Lactamase Production and Virulence of Escherichia coli K1  

UK PubMed Central (United Kingdom)

We report a patient with neonatal meningitis caused by a CTX-M-1–producing Escherichia coli K1 strain. The influence of CTX-M production on virulence was investigated in cell...Full Text Available

2009-12-01

284

APOD: 2000 May 27 - M51: The Center Of The Whirlpool  

Science.gov (United States)

will download the highest resolution version available. M51: The Center Of The Whirlpool Credit: N. Panagia (STScI, ESA), NASA Explanation: In the center of M51, a spiral...

2011-10-07

285

Ultra-thin {sup 242m}Am fuel elements in nuclear reactors. II  

Energy Technology Data Exchange (ETDEWEB)

There is growing interest in using {sup 242m}Am as a nuclear fuel for space reactors and nuclear batteries. In this paper, we discuss different {sup 242m}Am enrichments, as well as fuel weight requirements, to produce a critical reactor. It was found that relatively low enrichments of {sup 242m}Am, about 10 w/o, are enough to guarantee criticality. Such low enrichments might eliminate the need for a {sup 242m}Am enrichment process. It was also found that the best results for low {sup 242m}Am requirements are obtained with a moderator to fuel volume ratio of 10,000.

2004-04-21

286

Capacity of a Simultaneous Quantum Secure Direct Communication Scheme between the Central Party and Other M Parties  

Science.gov (United States)

We analyse the capacity of a simultaneous quantum secure direct communication scheme between the central party and other M parties via M+1-particle GHZ states and swapping quantum entanglement. It is shown that the encoding scheme should be secret if other M parties wants to transmit M+1 bit classical messages to the centre party secretly. However, when the encoding scheme is announced publicly, we prove that the capacity of the scheme in transmitting the secret messages is 2 bits, no matter how large M is.

2006-10-01

287

Buckling tests on axially compressed cylindrical shells made of various austenitic stainless steels at ambient and elevated temperatures  

Energy Technology Data Exchange (ETDEWEB)

The buckling test program comprised 37 axially loaded cylinders made of austenitic stainless steels and 6 reference cylinders made of mild steel. The three test parameters were the steel grade, the shell slenderness and the operating temperature. The chosen steel grades are typical for practical applications: AISI 304 (No. 1.4301) as the basic austenitic stainless steel, AISI 316 L (No. 1.4404) as a molybdenum alloyed and AISI 316 Ti (No. 1.4571) as a molybdenum and titanium alloyed austenitic stainless steel. The chosen shell slendernesses are typical for the above-mentioned elastic-plastic region: r/t=50, 150 and 400, approximately corresponding to non-dimensional slenderness parameters {lambda}=0.3, 0.5 and 0.9 respectively. The chosen testing temperatures cover a wide range of applications: T=20 C, 100 C, 250 C and 400 C. The test cylinders were manufactured from 3.0 mm, 1.0 mm and 0.5 mm steel sheets, cold rolled into the cylindrical shape ...

1998-12-01

290

R/V Laurence M. Gould LMG0303 - Development of a luminescence - NASA  

Science.gov (United States)

R/V Laurence M. Gould LMG0303 - Development of a luminescence dating capability for Antarctic glaciomarine sediments: Tests of signal zeroing at the ...

291

On penetration effect in M1 component of 70.45 keV #gamma#-transition in "1"7"7Ta  

International Nuclear Information System (INIS)

... gamma radiation l conversion m conversion mev range 10-100 mixing ratio

1987-04-14

293

Evaluation of the addition of various surfactant-suspended carbon nanotubes in MEEKC with an in situ-synthesized surfactant system  

British Library Electronic Table of Contents (United Kingdom)

Abstract Dispersions of single-walled carbon nanotubes (SWNTs) in various surfactant solutions have been systematically evaluated as additives in MEEKC. The compounds examined were catechins, phenolic acids, and flavonoids. Compared with zwitterionic and neutral surfactants, the addition of anionic dispersion seemed to be better at separating the three types of analytes in microemulsion system. In order to achieve low operating currents, an in situ-synthesized surfactant system based on the combination of a long-chain alkyl acid with an organic base was used in MEEKC. The optimized buffer contained 0.5% (57-mM) ethyl acetate, 0.6% (30-mM) lauric acid, 4.0% (666-mM) propanol, 50-mM Tris solution, and 4.5-mg/L the dispersion of SWNTs. Under optimized conditions, the established method was ap...

2011-01-01

294

Distribution and Taxonomy of Zooplankton in the Alboran Sea ...  

Science.gov (United States)

... Tregoubovia x atentaculataj Turritopsis nutricula M4-40 x Zanclea costata M4-41 x X X x x Leptomedusae ___ _____ __ ...

1991-09-01

296

BRAZING AND BONDING OF COLUMBIUM, MOLYBDENUM ...  

Science.gov (United States)

... Kingdom Atomic Energy Authority, .... G. .. aphit. J..int. Report No. AERE R/M 165 (April, 1958). (2) Slaughter, G. M., Metallurgy ...

1962-06-11

297

Approximate Analysis of an Unreliable M/M/2 Retrial Queue  

Science.gov (United States)

... by r repair crews, thus creating a second queue, that of failed terminals. The authors defined a trivariate stochastic process as follows: X(t) = 1 if ...

2007-03-01

299

An Optical Fiber Infrasound Sensor  

Science.gov (United States)

... We use a compliant, sealed tube helically wrapped with an optical fiber. ... 2.5 cm diameter compliant, sealed tube 10 m < length < 120 m ...

2000-09-01

300

APOD: 2002 July 10 - M51: Cosmic Whirlpool  

Science.gov (United States)

on the picture will download the highest resolution version available. M51: Cosmic Whirlpool Credit & Copyright: Tony and Daphne Hallas Explanation: Follow the handle of the Big...

2011-10-07

301

APOD: 2000 July 24 - M51: The Whirlpool Galaxy  

Science.gov (United States)

on the picture will download the highest resolution version available. M51: The Whirlpool Galaxy Credit & Copyright: Todd Boroson (NOAO), AURA, NOAO, NSF Explanation: The...

2011-10-07

302

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).

303

de Haas--van Alphen effect and Fermi surface of lutetium  

International Nuclear Information System (INIS)

We report de Haas--van Alphen measurements of the Fermi surface of lutetium at temperatures down to 0.3 K and in fields up to 150 kG in the (1010) and (1120) planes. Lutetium, having a filled 4f shell, serves as a nonmagnetic prototype of the structurally similar (hcp), trivalent, heavy rare-earth elements from Gd to Tm. The fact that no complete frequency branches were observed indicates that there are no closed pieces of the Fermi surface. We observed all but one orbit predicted by relativistic augmented-plane-wave calculations of Keeton and Loucks and by recent spin-orbit--linearized-augmented-plane-wave calculations of Tibbetts and Harmon. The data support a geometry similar to that of yttrium, and in good qualitative agreement with energy-band theory.

304

VARIATION IN SIZE, DEVELOPMENT, AND HOOK NUMBER AMONG THE ONCOSPHERES OF NORMAL AND IRRADIATED HYMENOLEPIS DIMINUTA  

Science.gov (United States)

Oncospheres produced by a nonirradiated worm and oncospheres produced by a worm that had been subjected to high gamma radiation (successive generations of cysticercoids were irradiated with 15,000 r until a cumulative dose of 120,000 r was obtained) were compared. Radiation had no effect on the sizes of the embryos, the shell, and the median hooks. Radiation may have resulted in certain large, hookless embryos that did not occur in the normal worm. Two anomalies, reduced hook number and failure of growth, were more frequent in the normal than in the irradiated worm. This result, although surprising, can be explained by the high selection pressure operating under the experimental conditions. (auth)

1962-01-01

305

Unitary constraints on Deeply Virtual Compton Scattering  

Energy Technology Data Exchange (ETDEWEB)

At moderately low momentum transfer ($-t$ up to 1 GeV$^2$) the coupling to the vector meson production channels gives the dominant contribution to real Compton and deeply virtual Compton scattering (DVCS). Starting from a Regge Pole approach that successfully describes vector meson production, the singular part of the corresponding box diagrams (where the intermediate vector meson-baryon pair propagates on-shell) is evaluated without any further assumptions (unitarity). Such a treatment explains not only the unexpectedly large DVCS unpolarized cross section that has been recently measured at Jefferson Laboratory (JLab), but also all the beam spin and charge asymmetries that has been measured at JLab and Hermes, without explicit need of Generalized Parton Distributions (GPD). The issue of the relationship between the two approaches is addressed.

2007-11-01

306

Two-step template-free route for synthesis of TiO2 hollow spheres  

British Library Electronic Table of Contents (United Kingdom)

The TiO2 hollow microspheres were prepared by microwave-assisted solvothermal treatment without template. The morphology and the phase of TiO2 hollow microspheres were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), and BET surface areas. The results show that the particles have hollow structures and the shell was covered by nanocrystals and have higher specific surface area. The possible formation mechanism of hollow TiO2 spherical structures has simply been proposed. The activity was evaluated by the photocatalytic degradation of methyl orange (MO). The results show that the particles having specific surface area show higher photocatalytic activity. It can be attribute to the doped ...

2011-01-01

307

Trace analysis in cadmium telluride by heavy ion induced X-ray emission and by SIMS  

International Nuclear Information System (INIS)

The possibilities of using both selective heavy ion induced X-ray emission and secondary ion mass spectroscopy (SIMS), for the identification of impurities present at low concentrations in cadmium telluride are examined. The relative concentrations of the impurities along CdTe crystals have been determined by exciting the X-ray emission of the elements in several slices with Ar and Kr ions and by comparing the relative characteristic X-ray emission yields. As a consequence of the quasimolecular inner shell ionization mechanism in heavy ion-atom collisions, Ar and Kr ions allow a strong excitation of the main impurities seen by SIMS namely Si, Cl and Ge, As, with only a minor contribution of Cd and Te. From the changes of the concentrations of the various impurities along the crystal, informations about segregation coefficients and compensation can be obtained.

2007-02-01

308

The preparation and properties of some activated carbons modified by treatment with phosgene or chlorine  

Energy Technology Data Exchange (ETDEWEB)

Treatment of coal or coconut shell activated carbons with either phosgene or chlorine at 180{degree}C followed by washing with methanol or water results in chlorinated carbons with very similar pore structures to their precursors. Water adsorption experiments show that the modified materials are relatively hydrophobic, presumably as a result of replacement of oxygen-containing surface groups by chlorine. Adsorption of the model hydrophobic vapour chloropicrin from humid air is usually better for the modified carbons which, unlike the controls, do not appear to be subject to degradation in performance on ageing in a humid atmosphere. The stability of the modified carbons is probably a consequence of the chlorination of those sites on the control carbons that are prone to ready oxidation or hydroxylation. 1 tab., 2 figs., 17 refs.

1992-01-01

309

The Australian Geographic Team Marsupial solar-powered car  

Energy Technology Data Exchange (ETDEWEB)

As in all vehicles of this type, low weight and aerodynamic drag must be achieved without compromising safety, and in an extremely rugged structure. This has been done by using a chrome-molybdenum steel space-frame, surrounded by a Kevlar/foam sandwich body shell. The solar panel wing, which uses a laminar flow section to obtain low drag, does not tilt except when the vehicle is stationary. A high degree of redundancy is built into the vehicle; for example there are two motors and transmissions, the solar array is divided into seven parallel sub-arrays, and the power electronics is multiply redundant. Built entirely in the garage of a suburban house, the Australian Geographic Team Marsupial car cost less than US$50,000 to construct.

1988-01-01

310

Superheavy elements with the Berkeley gas-filled separator  

Energy Technology Data Exchange (ETDEWEB)

In April and May of 1999 the Berkeley Gas-filled Separator was used to search for the production and decay of element 118 from the {sup 86}Kr + {sup 208}Pb reaction, according to Smolanczuk's predictions of relatively large production rates. Three decay chains, each consisting of an implanted heavy ion, followed by a rapid (ms) succession of high-energy (>10 MeV) alpha-particle decays were detected. These chains are consistent with the production and decay of element 118 with mass number 293. These results a) show experimental evidence for the existence of shell-stabilized superheavy elements, b) provide experimental values for refinement of nuclear mass models in the superheavy element region, and, most importantly, c) present a new' reaction pathway for the production of superheavy elements. (author)

2000-03-01

311

Structure of Heavy Fe Nuclei at the Point of Transition at N #approx# 37  

International Nuclear Information System (INIS)

We have studied energy levels in "6"3Fe populated in the #beta#-decay of "6"3Mn. A new (preliminary) level scheme of "6"3Fe includes 10 excited states connected by 21 #gamma#-rays. The first excited states at 357 and 451 keV have the level half-lives of 110 ps and 780 ps, respectively. Three states, at 357, 451 and 1132 keV, are strongly #beta#-fed with log ft #approx# 5, while there is only a very week #beta#-feeding, if any at all, to the ground state. The new results imply that "6"3Fe departs from a simple shell model structure observed for heavier N = 37 isotones of "6"5Ni and "6"7Zn. (author)

2009-03-01

312

Spectroscopy of {sup 25}Al and {sup 26,27,28}P using high-energy stripping reactions  

Science.gov (United States)

We report here results of an application of single-nucleon stripping reactions at high energies (65 MeV/u) in inverse kinematics to obtain spectroscopic factors. From measurements of the partial cross-sections for ground and excited states in residual nuclei formed in one-proton stripping reactions, single particle orbits and occupancies of light nuclei have been studied in the s-d shell. Single proton stripping cross-sections of {sup 25}Al and {sup 26,27,28}P on a Be target have been measured using the S800 spectrograph and the NaI(Tl) array at the NSCL. These results indicate that this technique may provide a general tool for the intermediate energy range analogous to transfer (pick-up) reactions at low-energy.

1998-12-21

313

Spectroscopy of neutron-rich {sup 59-63}Mn isotopes  

Science.gov (United States)

The neutron-rich Mn isotopes from A=59 to 63 have been studied through multi-nucleon transfer reactions by bombarding a {sup 238}U target with a beam of {sup 70}Zn at an energy of E{sub lab}=460 MeV. Prompt {gamma} rays measured by the CLARA array have been identified unambiguously for each nucleus, using coincidence relationships with ions detected in the high-acceptance magnetic spectrometer PRISMA. The new data extends the knowledge of the low-lying level structure of Mn isotopes, which is discussed in terms of the systematics of the region. Results are compared with large-scale shell-model calculations using different effective interactions and valence spaces.

2008-08-15

314

Spectroscopy of neutron-rich "5"9"-"6"3Mn isotopes  

International Nuclear Information System (INIS)

The neutron-rich Mn isotopes from A=59 to 63 have been studied through multi-nucleon transfer reactions by bombarding a "2"3"8U target with a beam of "7"0Zn at an energy of E_l_a_b=460 MeV. Prompt #gamma# rays measured by the CLARA array have been identified unambiguously for each nucleus, using coincidence relationships with ions detected in the high-acceptance magnetic spectrometer PRISMA. The new data extends the knowledge of the low-lying level structure of Mn isotopes, which is discussed in terms of the systematics of the region. Results are compared with large-scale shell-model calculations using different effective interactions and valence spaces.

2008-08-01

315

Spectroscopy of "2"5Al and "2"6","2"7","2"8P using high-energy stripping reactions  

International Nuclear Information System (INIS)

We report here results of an application of single-nucleon stripping reactions at high energies (65 MeV/u) in inverse kinematics to obtain spectroscopic factors. From measurements of the partial cross-sections for ground and excited states in residual nuclei formed in one-proton stripping reactions, single particle orbits and occupancies of light nuclei have been studied in the s-d shell. Single proton stripping cross-sections of "2"5Al and "2"6","2"7","2"8P on a Be target have been measured using the S800 spectrograph and the NaI(Tl) array at the NSCL. These results indicate that this technique may provide a general tool for the intermediate energy range analogous to transfer (pick-up) reactions at low-energy.

1998-12-21

316

Software development for a switch-based data acquisition system  

Energy Technology Data Exchange (ETDEWEB)

We report on the software aspects of the development of a switch-based data acquisition system at Fermilab. This paper describes how, with the goal of providing an integrated systems engineering'' environment, several powerful software tools were put in place to facilitate extensive exploration of all aspects of the design. These tools include a simulation package, graphics package and an Expert System shell which have been integrated to provide an environment which encourages the close interaction of hardware and software engineers. This paper includes a description of the simulation, user interface, embedded software, remote procedure calls, and diagnostic software which together have enabled us to provide real-time control and monitoring of a working prototype switch-based data acquisition (DAQ) system.

1991-12-01

317

Software development for a switch-based data acquisition system  

Energy Technology Data Exchange (ETDEWEB)

We report on the software aspects of the development of a switch-based data acquisition system at Fermilab. This paper describes how, with the goal of providing an ``integrated systems engineering`` environment, several powerful software tools were put in place to facilitate extensive exploration of all aspects of the design. These tools include a simulation package, graphics package and an Expert System shell which have been integrated to provide an environment which encourages the close interaction of hardware and software engineers. This paper includes a description of the simulation, user interface, embedded software, remote procedure calls, and diagnostic software which together have enabled us to provide real-time control and monitoring of a working prototype switch-based data acquisition (DAQ) system.

1991-12-01

318

Simplification of Finite Element Models for Structures Having a Beam-Like Behaviour  

Science.gov (United States)

A method for simplifying finite element models of structures having a beam-like global dynamical behaviour is presented. This method is based on the use of a general uniform beam finite element formulation. It takes into account both transverse shear effects and dynamical coupling between bending and torsion due to the fact that mass centres and shear centres do not always coincide. For that purpose, we develop a condensation method for reducing any shell model into an equivalent beam, as well as a technique for automatically identifying the corresponding set of beam parameters. The method is applied to several illustrate examples that demonstrate its ability to simplify finite element models for many kinds of sophisticated structures having a beam-like predominant behaviour.

2000-04-01

319

Renormalization of Lorentz non-invariant actions and manifest T-duality  

CERN Document Server

We study general two-dimensional sigma-models which do not possess manifest Lorentz invariance. We show how demanding that Lorentz invariance is recovered as an emergent on-shell symmetry constrains these sigma-models. The resulting actions have an underlying group-theoretic structure and resemble Poisson--Lie T-duality invariant actions. We consider the one-loop renormalization of these models and show that the quantum Lorentz anomaly is absent. We calculate the running of the couplings in general and show, with certain non-trivial examples, that this agrees with that of the T-dual models obtained classically from the duality invariant action. Hence, in these cases solving constraints before and after quantization are commuting operations.

2009-01-01

320

Relativistic distorted-wave results for nickel-like gadolinium  

Science.gov (United States)

Electron collisional data are required for population kinetics modeling and spectral predictions of highly ionized ions in high-temperature plasmas. Nickel-like ions are especially interesting for their potential use in soft X-ray laser schemes pumped by electron collisional excitation and recombination. For highly stripped ions of moderate to high Z, relativistic effects begin to play a role in the atomic-physics calculations. A relativistic multiconfigurational distored-wave model has been used for the calculation of electron excitation cross sections and rate coefficients between the 3s2 3p6 3d10 Ni-like Gd ground state and the singly excited states with an N-shell electron.

1986-08-01

321

Radium concentration factors and their use in health and environmental risk assessment  

Energy Technology Data Exchange (ETDEWEB)

Radium is known to be taken up by aquatic animals, and tends to accumulate in bone, shell and exoskeleton. The most common approach to estimating the uptake of a radionuclide by aquatic animals for use in health and environmental risk assessments is the concentration factor method. The concentration factor method relates the concentration of a contaminant in an organism to the concentration in the surrounding water. Site specific data are not usually available, and generic, default values are often used in risk assessment studies. This paper describes the concentration factor method, summarizes some of the variables which may influence the concentration factor for radium, reviews reported concentration factors measured in marine environments and presents concentration factors derived from data collected in a study in coastal Louisiana. The use of generic default values for the concentration factor is also discussed.

1991-01-01

322

Radium concentration factors and their use in health and environmental risk assessment  

Energy Technology Data Exchange (ETDEWEB)

Radium is known to be taken up by aquatic animals, and tends to accumulate in bone, shell and exoskeleton. The most common approach to estimating the uptake of a radionuclide by aquatic animals for use in health and environmental risk assessments is the concentration factor method. The concentration factor method relates the concentration of a contaminant in an organism to the concentration in the surrounding water. Site specific data are not usually available, and generic, default values are often used in risk assessment studies. This paper describes the concentration factor method, summarizes some of the variables which may influence the concentration factor for radium, reviews reported concentration factors measured in marine environments and presents concentration factors derived from data collected in a study in coastal Louisiana. The use of generic default values for the concentration factor is also discussed.

1991-12-31

323

Quiet innovation adds flexibility to global lending. [Energy finance markets  

Energy Technology Data Exchange (ETDEWEB)

Few major mandates were won or lost in the first quarter of 1993, as the energy industry adopted a conservative approach to its financing needs. However, indications are that energy companies are coming back to the syndicated loan market after this quiet first quarter. Already, Enron, Shell Oil and Coastal have mandated substantial new facilities. Many more companies are expected back in the market over the new few months, including at least one jumbo for a major international name. A number of the industry's top names report that pricing is once again getting more aggressive in response to the high level of liquidity among lenders and a shortage of new mandates over the last few months. (Author)

1993-06-01

324

Prompt J/Psi production at LHC: new evidence for the kt-factorization  

CERN Document Server

In the framework of the kt-factorization approach, the production and polarization of prompt J/Psi mesons in pp collisions at the LHC energy 7 TeV is studied. Both the direct production mechanism as well as feed-down contributions from chic1, chic2 and psi' decays are taken into account. Our consideration is based on the color singlet model supplemented with the off-shell matrix elements for the corresponding partonic subprocesses. The unintegrated gluon densities in a proton are determined using the CCFM evolution equation as well the Kimber-Martin-Ryskin prescription. We compare our numerical predictions with the first experimental data taken by the CMS, ATLAS and LHCb collaborations. The estimation of all polarization parameters which determine J/Psi spin density matrix is performed.

2011-01-01

325

Pressure-induced structural transitions in multi-walled carbon nanotubes  

British Library Electronic Table of Contents (United Kingdom)

We demonstrate a novel cross-sectional deformation, called the radial corrugation, of multi-walled carbon nanotubes (MWNTs) under hydrostatic pressure. Theoretical analyses based on the continuum elastic approximation have revealed that MWNTs consisting of more than ten concentric walls undergo elastic deformations at critical pressure Formula Not Shown , above which the circular shape of the cross-section becomes radially corrugated. Various corrugation modes have been observed by tuning the innermost tube diameter and the number of constituent walls, which is a direct consequence of the core-shell structure of MWNTs. Cross-sectional views of MWNT under high hydrostatic pressure: elliptic deformation with the mode index n = 2 (left), and radial corrugations with n = 5 (center), and n = 6 ...

2009-01-01

326

Precipitation of ions induced by nonadiabatic motion in the outer cusp region  

Science.gov (United States)

The transport of magnetospheric particles in the outer cusp region is examined by means of three-dimensional single particle codes. It is shown that, at high altitudes, particles can experience nonadiabatic motions leading to significant magnetic moment changes. It is demonstrated that this nonadiabatic behavior can be interpreted, at least partly, by the action of an impulsive centrifugal force perturbing the particle gyromotion. Systematic trajectory calculations reveal that plasma sheet ions which ExB convert toward the magnetopause from low L-shells in the dayside sector are subjected to such nonadiabatic motions. As a result of magnetic moment damping, a number of them are injected into the loss cone and subsequently precipitate near the cusp equatorward edge.

327

Pion dominance in R-parity violating supersymmetry induced neutrinoless double beta decay  

International Nuclear Information System (INIS)

At the quark level there are basically two types of contributions of R-parity violating supersymmetry (Rep SUSY) to neutrinoless double beta decay: the short-range contribution involving only heavy virtual superpartners and the long-range one with the virtual squark and neutrino. Hadronization of the effective operators, corresponding to these two types of contributions, may in general involve virtual pions in addition to close on-mass-shell nucleons. From the previous studies it is known that the short-range contribution is dominated by the pion exchange. In the present paper we show that this is also true for the long-range Rep SUSY contribution. Therefore, we conclude that the Rep SUSY contributes to the neutrinoless double beta decay dominantly via charged pion exchange between the decaying nucleons.

2008-06-01

328

Photon shell game in three-resonator circuit quantum electrodynamics  

CERN Document Server

The generation and control of quantum states of light constitute fundamental tasks in cavity quantum electrodynamics (QED). The superconducting realization of cavity QED, circuit QED, enables on-chip microwave photonics, where superconducting qubits control and measure individual photon states. A long-standing issue in cavity QED is the coherent transfer of photons between two or more resonators. Here, we use circuit QED to implement a three-resonator architecture on a single chip, where the resonators are interconnected by two superconducting phase qubits. We use this circuit to shuffle one- and two-photon Fock states between the three resonators, and demonstrate qubit-mediated vacuum Rabi swaps between two resonators. This illustrates the potential for using multi-resonator circuits as photon quantum registries and for creating multipartite entanglement between delocalized bosonic modes.

2010-01-01

329

Phenotypic variation of baobab (Adansonia digitata L.) fruit traits in Mali  

British Library Electronic Table of Contents (United Kingdom)

We analyzed the phenotypic variation of baobab (Adansonia digitata L.) fruits from Mali to define the domestication potential of this species. 269 trees, selected from 10 provenances distributed along a rainfall gradient, were characterized. Five fruits were sampled from each tree. Total individual fruit weight was partitioned into shell, pulp, and seed weight. Ratios were calculated between pulp?+?seed and total weight, and between pulp and seed weight. For all the measured fruit traits, we detected significant differences between provenances, as well as between trees from the same provenance. Assuming that the measured traits are under genetic control, the latter facts indicate that there are considerable opportunities for tree selection on a local scale. However, candidate plus trees wi...

2011-01-01

330

Nanowires of silicon carbide and 3D SiC/C nanocomposites with inverse opal structure  

International Nuclear Information System (INIS)

Synthesis, morphology, structural and optical characteristics of SiC NWs and SiC/C nanocomposites with an inverse opal lattice have been investigated. The samples were prepared by carbothermal reduction of silica (SiC NWs) and by thermo-chemical treatment of opal matrices (SiC/C) filled with carbon compounds which was followed by silicon dioxide dissolution. It was shown that the nucleation of SiC NWs occurs at the surface of carbon fibers felt. It was observed three preferred growth direction of the NWs: [111], [110] and [112]. HRTEM studies revealed the mechanism of the wires growth direction change. SiC/C- HRTEM revealed in the structure of the composites, except for silicon carbide, graphite and amorphous carbon, spherical carbon particles containing concentric graphite shells (onion-like particles).

2011-07-07

331

NONLINEAR OPTICAL PHENOMENA: Nonlinear optical properties of colloidal silver nanoparticles produced by laser ablation in liquids  

Science.gov (United States)

The optical and nonlinear optical properties of colloidal solutions of silver obtained by laser ablation in water and ethanol are studied. It is shown that freshly prepared colloids experience a full or partial sedimentation by changing their nonlinear optical properties. Aqueous colloids undergo a partial sedimentation and their nonlinear optical absorption changes to nonlinear optical transmission. The obtained results are interpreted using the Drude model for metal particles taking the particle size into account and can be explained by the sedimentation of larger silver particles accompanied by the formation of a stable colloid containing silver nanoparticles with a tentatively silver oxide shell. The characteristic size of particles forming such a stable colloid is determined and its optical nonlinearity is estimated.

2004-07-01

332

Molecular dynamics study of TiO2/poly(acrylic acid-co-methyl methacrylate) and Fe3O4/polystyrene composite latex particles prepared by heterocoagulation  

British Library Electronic Table of Contents (United Kingdom)

All-atom molecular dynamics simulations were used to study the morphology of polymer/inorganic composite particles prepared by heterocoagulation. The results were also compared to those of our previous study of the preparation of TiO2/poly(acrylic acid-co-methyl methacrylate) and Fe3O4/polystyrene composite particles. In the simulation system, polymer or inorganic particles were simulated by surface-charge-modified C60 or Na atoms. Through a combination of analysis of the radial distribution functions of charged atoms and snapshots of the equilibrated structure, three kinds of particle distributions were observed under different conditions. When the polymer and inorganic particles had opposite surface charges and their sizes were very different, the composite morphology showed a core-shell...

2010-01-01

333

Microscopic Origin of the Phenomenological Equilibrium ''Doping Limit Rule'' in n -Type III-V Semiconductors  

International Nuclear Information System (INIS)

The highest equilibrium free-carrier doping concentration possible in a given material is limited by the ''pinning energy'' which shows a remarkable universal alignment in each class of semiconductors. Our first-principles total energy calculations reveal that equilibrium n -type doping is ultimately limited by the spontaneous formation of close-shell acceptor defects: the 3- -charged cation vacancy in AlN, GaN, InP, and GaAs and the 1- -charged DX center in AlAs, AlP, and GaP. This explains the alignment of the pinning energies and predicts the maximum equilibrium doping levels in different materials. (c) 2000 The American Physical Society

2000-02-07

334

Mechanism of nanocapsules of Matricaria recutita L. extract formation by the emulsion-diffusion process  

British Library Electronic Table of Contents (United Kingdom)

Nanocapsules coated by medicinal plants have many applications in drug manufacturing. Medicinal plants can be loaded on nanocapsules with polyesteric triblock copolymer poly ethylene glycol-poly butylene adipate-poly ethylene glycol (PEG-PBA-PEG) as shell and olive oil can be introduced as a core of nanocapsules by a method known as polymer deposition solvent evaporation method. In this research, first, certain amount of polymer, Matricaria recutita extract and olive oil were mixed with acetone and then, water was added to the solution using magnetic stirrer. After which the acetone was removed by vacuuming and finally nanocapsules were found by freezing-drier. The study showed the size of nanocapsules depends on variety of factors such as the ratio of polymer to oil and concentration of p...

2011-01-01

335

Measurements of K-beta/K-alpha X-ray intensity ratios using VEC beams  

International Nuclear Information System (INIS)

An experiment on the K#beta#/K#alpha# characteristic X-ray intensity ratio in silver was performed at VEC Centre, Calcutta using the #alpha#-beams at energies 40 MeV and 50 MeV employing a Si(Li) detector system on-line. The results show that the K#beta#/K#alpha# X-ray intensity ratio at energies 40 and 50 MeV are 0.215 #+-# 0.006 and 0.216 #+-# 0.006, respectively, which indicates no change with beam energy and in accordance with the earlier reports. The present experiment shows the feasibility of studying the K#beta#/K#alpha# ratios as a function of beam energy in different regions of periodic table. Experiments in elements belonging to the 3d shell and their compounds are suggested to look for the chemical effects and their dependence on #alpha#-energy. (author). 7 refs.

1987-02-03

336

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

337

In situ ligand exchange of thiol-capped CuInS2/ZnS quantum dots at growth stage without affecting luminescent characteristics  

British Library Electronic Table of Contents (United Kingdom)

An aliphatic thiol ligand of CuInS2/ZnS core/shell quantum dots is replaced with a hydroxyl-terminated thiol ligand by utilizing `on-off state' of ligands during growth stage of the quantum dots. After the ligand-exchange, negligible differences were observed on both photoluminescence spectrum and luminescent quantum efficiency. The reason for the high retention of luminescent efficiency comes from no local agglomeration and no surface deterioration of QDs. It is also observed that 70% of initial ligands are exchanged by the replacing ligand, determined by FT-IR and 1H NMR. The proposed method provides the quantum dots with an excellent dispersibility in polar solvents, supported by identical luminescence decay characteristics of the QDs.

2011-01-01

338

Impact of developing technology on indirect liquefaction  

Energy Technology Data Exchange (ETDEWEB)

The status of commercial technology for indirect liquefaction, as exemplified by SASOL facilities in South Africa, is reviewed. The impact of substituting more advanced gasifiers and synthesis systems is then investigated. Slagging BGC/Lurgi, Texaco and Shell-Koppers gasifiers were substituted for the Dry Ash Lurgi units used at SASOL. SASOL SYNTHOL synthesis units were replaced by slurry phase Fischer-Tropsch units employing technology pioneered by Kolbel. The advanced systems were found to have a highly favorable impact on plant efficiency, product distribution and gasoline cost. If all the projected technical improvements can be realized for indirect liquefaction, the yields of refined transportation fuels per ton of coal will approach those anticipated for direct liquefaction processes.

1980-11-01

339

Hanford Waste Management Plan, 1987  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the Hanford Waste Management Plan (HWMP) is to provide an integrated plan for the safe storage, interim management, and disposal of existing waste sites and current and future waste streams at the Hanford Site. The emphasis of this plan is, however, on the disposal of Hanford Site waste. The plans presented in the HWMP are consistent with the preferred alternative which is based on consideration of comments received from the public and agencies on the draft Hanford Defense Waste Environmental Impact Statement (HDW-EIS). Low-level waste was not included in the draft HDW-EIS whereas it is included in this plan. The preferred alternative includes disposal of double-shell tank waste, retrievably stored and newly generated TRU waste, one pre-1970 TRU solid waste site near the Columbia River and encapsulated cesium and strontium waste.

1987-01-01

340

Ge/Si nanowire mesoscopic Josephson junctions  

CERN Document Server

The controlled growth of nanowires (NWs) with dimensions comparable to the Fermi wavelengths of the charge carriers allows fundamental investigations of quantum confinement phenomena. Here, we present studies of proximity-induced superconductivity in undoped Ge/Si core/shell NW heterostructures contacted by superconducting leads. By using a top gate electrode to modulate the carrier density in the NW, the critical supercurrent can be tuned from zero to greater than 100 nA. Furthermore, discrete sub-bands form in the NW due to confinement in the radial direction, which results in stepwise increases in the critical current as a function of gate voltage. Transport measurements on these superconductor-NW-superconductor devices reveal high-order (n = 25) resonant multiple Andreev reflections, indicating that the NW channel is smooth and the charge transport is highly coherent. The ability to create and control coherent superconducting ordered states in ...

2006-01-01

341

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

342

First observation of excited states in the T_z=1/2 nucleus "8"5Mo  

International Nuclear Information System (INIS)

Excited states in the T_z=(1/2) nucleus "8"5Mo have been observed for the first time with the reaction "5"8Ni("3"2S,#alpha#n#gamma#) at 105 MeV. #gamma#-ray transitions in this nucleus have been assigned unambiguously by combining the information from the GASP #gamma#-ray array, the ISIS silicon ball, and the n-Ring neutron detector. Two band structures have been observed in this nucleus; they continue the smooth evolution of the known bands from the lighter N=43 isotones and have been tentatively assigned spins and parity on this basis. After reaching a maximum of collectivity at "8"3Zr, the trend with increasing mass is reversed, showing a smaller collectivity at "8"5Mo. The rotational behavior of the observed bands is discussed on the basis of the projected shell model calculations.

2002-03-01

343

Evolutionary developments advancing the floating production, storage, and offloading concept  

Energy Technology Data Exchange (ETDEWEB)

Tanker-based floating production, storage and offloading (FPSO) systems have been in operation since Aug. 1977, when a single-well FPSO was put into production by Shell Espana in the Mediterranean. The overall operational experience with this system at this field is reviewed. Special attention is directed to the wireline workover facilities which have proven to be satisfactory. A subsequent evolutionary step, a FPSO accommodating multiple wells, necessitated development of a multiple-bore product swivel. A design program for this swivel was initiated in 1978, a prototype was built and fullscale testing finalized in 1980. A summary of the test results is presented. Simultaneous with the multiple-bore swivel development, detailed engineering for an 8-well FPSO was begun. This sytem includes gas lift a

1982-01-01

344

Diphtheria toxoid conformation in the context of its nanoencapsulation within liposomal particles sandwiched by chitosan  

British Library Electronic Table of Contents (United Kingdom)

Chitosan (a?-(1-4)-amino-2-deoxy-b?-D-glucan) is a deacetylated form of chitin, a polysaccharide from crustacean shells. Its unique characteristics, such as positive charge, biodegradability, biocompatibility, nontoxicity, and rigid structure, make this macromolecule ideal for an oral vaccine delivery system. We prepared reverse-phase evaporation vesicles (REVs) sandwiched by chitosan (Chi) and polyvinylic alcohol (PVA). However, in this method, there are still some problems to be circumvented related to protein stabilization. During the inverted micelle phase of protein nanoencapsulation, hydrophobic interfaces are expanded, leading to interfacial adsorption, followed by protein unfolding and aggregation. Here, spectroscopic and immunological techniques were used to ascertain the effects ...

2011-01-01

345

Determination of ratios of emission probabilities of Auger electrons and K-L-shell radiative vacancy transfer probabilities for 17 elements from Mn to Mo at 59.5keV  

Energy Technology Data Exchange (ETDEWEB)

The measurements of the K X-ray intensity ratio I(K{sub {beta}})/I(K{sub {alpha}}) for the 17 elements Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, As, Se, Br, Rb, Sr, Y, Zr, Nb and Mo have been done following ionization by 59.5keV {gamma}-rays from a {sup 241}Am point source. Ratios of emission probabilities of Auger electrons and the vacancy transfer coefficients have been extracted in terms of the intensity ratios. It is found that the present results agree well with earlier fitted values and the semi-empirical values.

2006-01-15

346

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.

347

Decays of "1"0"1Mo and "1"0"1Tc  

International Nuclear Information System (INIS)

The activities "1"0"1Mo and "1"0"1Tc produced from neutron capture by natural Mo were chemically separated and studied using Ge(Li) #gamma#-ray detectors. Out of 185 transitions observed in the decay of "1"0"1Mo, 170 were assigned to 44 excited levels in "1"0"1Tc. For the decay of "1"0"1Tc, 26 of 27 transitions were placed among 10 excited levels in "1"0"1Ru. The interpretation of the "1"0"1Tc level scheme using the shell-model approach is not satisfactory even for a five-particle calculation. Systematics of odd-A level structures in the region of A=101 indicate that the level structure of "1"0"1Tc could be due partly to the onset of collective effects.

348

Decay of very neutron-rich Mn nuclides and vanishing of the N=40 subshell closure in {sup 66}Fe  

Science.gov (United States)

The use of chemically selective laser ionization combined with beta-delayed neutron counting at ISOLDE has permitted identification and half-life measurements for {sup 61}Mn up through {sup 69}Mn. The 14(4)-ms half life for {sup 69}Mn is one of the shortest determined for any nuclide beyond the sd shell. Gamma-ray singles and coincidence spectra have been determined for the decays of {sup 64,66}Mn to levels of {sup 64,66}Fe, revealing strong deformation and vanishing of the N=40 subshell in the Fe isotopes. {copyright} {ital 1998 American Institute of Physics.}

1998-12-01

349

Decay of very neutron-rich Mn nuclides and vanishing of the N=40 subshell closure in "6"6Fe  

International Nuclear Information System (INIS)

The use of chemically selective laser ionization combined with beta-delayed neutron counting at ISOLDE has permitted identification and half-life measurements for "6"1Mn up through "6"9Mn. The 14(4)-ms half life for "6"9Mn is one of the shortest determined for any nuclide beyond the sd shell. Gamma-ray singles and coincidence spectra have been determined for the decays of "6"4","6"6Mn to levels of "6"4","6"6Fe, revealing strong deformation and vanishing of the N=40 subshell in the Fe isotopes.

1998-12-21

350

Decay of Neutron-Rich Mn Nuclides and Deformation of Heavy Fe Isotopes  

Energy Technology Data Exchange (ETDEWEB)

The use of chemically selective laser ionization combined with {beta} -delayed neutron counting at CERN/ISOLDE has permitted identification and half-life measurements for 623-ms {sup 61}Mn up through 14-ms {sup 69}Mn . The measured half-lives are found to be significantly longer near N=40 than the values calculated with a quasiparticle random-phase-approximation shell model. Gamma-ray singles and coincidence spectroscopy has been performed for {sup 64,66}Mn decays to levels of {sup 64,66}Fe , revealing a significant drop in the energy of the first 2{sup +} state in these nuclides that suggests an unanticipated increase in collectivity near N=40 . {copyright} {ital 1999} {ital The American Physical Society }

1999-02-01

351

Decay of Neutron-Rich Mn Nuclides and Deformation of Heavy Fe Isotopes  

International Nuclear Information System (INIS)

The use of chemically selective laser ionization combined with #beta# -delayed neutron counting at CERN/ISOLDE has permitted identification and half-life measurements for 623-ms "6"1Mn up through 14-ms "6"9Mn . The measured half-lives are found to be significantly longer near N=40 than the values calculated with a quasiparticle random-phase-approximation shell model. Gamma-ray singles and coincidence spectroscopy has been performed for "6"4","6"6Mn decays to levels of "6"4","6"6Fe , revealing a significant drop in the energy of the first 2"+ state in these nuclides that suggests an unanticipated increase in collectivity near N=40 . copyright 1999 The American Physical Society.

1999-02-01

352

Correlated charge-changing uion-atom collisions. Final Technical Report  

International Nuclear Information System (INIS)

This document comprises the final technical report for atomic collisions research supported by DOE grant No. DE-FG02-87ER13778 from September 1, 2001 through August 31, 2004. The research involved the experimental investigation of excitation and charge-changing processes occurring in ion-atom and ion-molecule collisions. Major emphases of the study were: (1) interference effects resulting from coherent electron emission in H2, (2) production of doubly vacant K-shell (hollow ion) states due to electron correlation, and (3) formation of long-lived metastable states in electron transfer processes. During the period of the grant, this research resulted in 23 publications, 12 invited presentations, and 39 contributed presentations at national and international meetings and other institutions. Brief summaries of the completed research are presented below.

2005-11-01

353

Chitinolytic enzyme production and genetic improvement of a new isolate belonging to Streptomyces anulatus  

British Library Electronic Table of Contents (United Kingdom)

Thirty bacterial isolates were obtained from different sources and sites at Jeddah, Saudi Arabia, on chitin agar medium; 9 of the 30 isolates were cultured in liquid medium containing chitin as sole carbon and nitrogen sources. Isolate SM21, which was isolated from shrimp shells, showed the best growth and chitinase production in liquid medium. According to its morphological, physiological and biochemical characteristics, SM21 belongs to the genus Streptomyces and was identified as Streptomyces anulatus SM21. Identification was confirmed using 16S rDNA analysis. The chitinase enzyme was precipitated with 80% NH4SO4 and purified using DEAE-cellulose ion exchange chromatography followed by Sephadex G-100 gel filtration. The molecular weight determined using sodium dodecyl sulfate polyacrylam...

2011-01-01

354

CFD analysis and overheating control of a turbine  

Energy Technology Data Exchange (ETDEWEB)

The thermal analysis of a turbine stack discharging exhaust gases to the atmosphere is presented. The examined turbine stack belongs to a gas lift plant for oil extraction located in the Gulf area. The analysis has been performed because an overheating of the anchor flange/bolts and of the concrete foundation occurred and caused small cracks in the upper layer of the foundation. A qualitative thermal analysis of the stack has pointed out that the main cause of the overheating was the thermal radiation in the air-filled region underneath the stack bottom plate. Detailed calculations performed by using a CFD code (Fluent ver. 6.0.12), cross-checked with measurements taken from site, have shown that a significant reduction of the heat flux to the foundation could be obtained by filling the above mentioned air region with an insulating material. The benefits of this solution are prevailing over those achievable with the installation of external fins on the stack shell. ...

2004-11-01

355

Augmentation of laminar flow and heat transfer in flat tubes by means of helical screw-tape inserts  

British Library Electronic Table of Contents (United Kingdom)

The heat transfer a characteristics and friction factor in the horizontal double pipes of flat tubes with full length helical screw element of different twist ratio and helical screw inserts with different spacer length are investigated. Cold and hot water are used as working fluid in tube side and shell side respectively. The experiments covered a range of Reynolds numbers 5.7x102Re1.31x103. The effect of spacer length on the heat transfer augmentation and friction factor and the effect of twist ratio on heat transfer augmentation and friction factor have been presented separately. The study shows that, the Nusslet number (Nu) and friction factor (f) decrease with the increase of S or Y for flat tube. The comparison between the data of present plain circular with that of previous plain ci...

2011-01-01

356

Atomic density functions: atomic physics calculations analyzed with methods from quantum chemistry  

CERN Document Server

This contribution reviews a selection of findings on atomic density functions and discusses ways for reading chemical information from them. First an expression for the density function for atoms in the multi-configuration Hartree--Fock scheme is established. The spherical harmonic content of the density function and ways to restore the spherical symmetry in a general open-shell case are treated. The evaluation of the density function is illustrated in a few examples. In the second part of the paper, atomic density functions are analyzed using quantum similarity measures. The comparison of atomic density functions is shown to be useful to obtain physical and chemical information. Finally, concepts from information theory are introduced and adopted for the comparison of density functions. In particular, based on the Kullback--Leibler form, a functional is constructed that reveals the periodicity in Mendeleev's table. Finally a quantum similarity measure is ...

2011-01-01

357

Application of the grazing angle polarized neutron reflectometry to study the magnetism in thin films and stratified media  

Energy Technology Data Exchange (ETDEWEB)

From optical point of view and due to the magnetic interaction of the cold neutrons with the unpaired electron shell, magnetic materials hae a neutron spin-dependent refractive index n[sup +] [spin up] and n[sup -] [spin down]. Magnetic media such as Fe, Co and Ni react like birefringent uniaxial crystals in ordinary optica. n[sup +] and n[sup -] are the equivalent of the ordinary and extraordinary refractive indices. The specular reflection of spin polarized neutrons which is due to the discontinuity of the magnetic induction at the surface of the ferromagnet is a sensitive probe of surface and interface magnetism. We shall first give the background of the art of polarized neutron optics. Secondly, some recent examples from surface and interface magnetism will be given to illustrate the power of this technique such as the magnetic coupling in thin films and multilayers and flux penetration in superconductors. (orig.).

1992-12-01

358

A simple one-step fabrication of micrometer-scale hierarchical TiO2 hollow spheres  

British Library Electronic Table of Contents (United Kingdom)

Hierarchical TiO2 hollow spheres had been prepared based on bubble templates by a simple one-step hydrothermal method. The diameter of hollow spheres was about 700nm and the shell thickness of them was 69nm. They were composed of similar spindle- or needle-like building units. Furthermore, hydrothermal time had an important influence on the morphology and crystallinity of hollow spheres. Moreover, the UV-Vis diffuse reflectance spectra of TiO2 hollow spheres heated at 150^oC for 10h showed the strongest absorption in the UV-Vis region and the Raman spectrum demonstrated the anatase sample. Additionally, a possible formation mechanism of TiO2 hollow spheres was proposed. So this novel and simple method would provide a development direction to fabricate all kinds of inorganic hollow spheres ...

2010-01-01

359

A Complete Detonator, Booster, and Main Charge Study of LX-07/PBX 9502  

British Library Electronic Table of Contents (United Kingdom)

Abstract A complete study of an exploding bridgewire detonator (EBW), an LX-07 hemispherical booster and a PBX 9502 outer shell are described. Breakout times from all three are listed in terms of first impact on the booster, i.e., code times. Lucite windows are also used to obtain particle velocities at the edges of each explosive, and these are converted into explosive pressures. The key to modeling is the use of the profile of the aluminum detonator can as it impacts the booster, i.e., we need to know the curvature of the end of the booster can. Modeling even with coarse zoning shows that (i) using reactive flow in the booster is better than programmed burn, (ii) creating the flyer curvature helps, and (iii) creating the time differences of flyer impact helps even more.

2011-01-01

360

nasa_d_FEDMACSOILAIRTEMP.xml  

Science.gov (United States)

S.M. Goltz; NASA Goddard Space Flight Center, Forest Ecosystem Dynamics Project ...

361

lub5022o.339  

Science.gov (United States)

KIGKNDEJJNEIMKGDGEDEDFCEFGHIEKOTkbCDGB@DHDEIFFBMOJDMGCLIKSOUUNNDFEEEEDFEDEFEHPM^ y\\GFEB>GCEGC?M@L>ADEBFPIHGRXRSRCFEFFDDFFDEDDJONfrJKIFD? ...

363

The sup(187m)Ir isomer state and its decay scheme  

International Nuclear Information System (INIS)

... beta spectrometers comparative evaluations data decay electrons

364

The ALPHA programs and thermal-hydraulic facilities at PSI  

International Nuclear Information System (INIS)

... J. DREIER, M. HUGGENBERGER, C. AUBERT, TH BANDURSKI, F. DE

1999-12-01

367

Primary structure of streptococcal Pep M5 protein: Absence of extensive sequence repeats  

UK PubMed Central (United Kingdom)

Extensive sequence repeats have been observed in a biologically active fragment of type 24 streptococcal M protein, namely Pep M24 [Beachey, E. H., Sayer, J. M. & Kang, A. H. (1978) Proc....Full Text Available

1983-09-01

368

New Variant of CTX-M-Type Extended-Spectrum ?-Lactamases, CTX-M-71, with a Gly238Cys Substitution in a Klebsiella pneumoniae Isolate from Bulgaria?  

UK PubMed Central (United Kingdom)

A single Klebsiella pneumoniae strain isolated in a Bulgarian hospital was found to produce CTX-M-71, a new CTX-M variant characterized by one amino acid substitution...Full Text Available

2009-10-01

369

Measurement of radiative, Auger, and nonradiative currents in 1. 3-. mu. m InGaAsP buried heterostructure lasers  

Energy Technology Data Exchange (ETDEWEB)

Frequency response measurements are used to determine the carrier lifetime of 1.3-..mu..m InGaAsP buried heterostructure lasers between 1 mA and threshold. The data confirm previous results on the radiative and Auger recombination coefficients and reveal the presence of a nonradiative current which dominates at low currents and contributes 4 mA at threshold.

1987-02-09

370

Individual products of the adenovirus 12S and 13S EIa mRNAs stimulate viral EIIa and EIII expression at the transcriptional level.  

UK PubMed Central (United Kingdom)

Recombinant plasmids containing mutant or wild-type adenovirus serotype 2 EIa genes that produce the 12S mRNA alone, the 13S mRNA alone, or both mRNAs were cotransfected into HeLa cells with plasmids...Full Text Available

1984-07-01

371

IEE, accelerated waste mgt, McM  

Science.gov (United States)

... in ATCM Recommendation XIV-2. The USAP's materials and waste management efforts are consistent with ...

372

Gutta-percha of Maytenus acanthophylla (Celastraceae)  

International Nuclear Information System (INIS)

Portuguese 2004 [1 p.] Brazil Oliveira, Djalma M. Ferraz, Vany Duarte,

376

Effect of energy intake on the metabolism of glucose and glutamine in rumen epithelial tissue  

International Nuclear Information System (INIS)

Ten Holstein steers (579 kg average body weight) were fed either alfalfa hay (12.2% crude protein) or a 90% concentrate diet to supply 14.2 or 25.2 Mcal ME respectively for a minimum of 28 days. Samples of rumen epithelial tissue were removed at slaughter from the anterior ventral sac, washed free of feed particles and transported to the laboratory in oxygenated Krebs-Ringer bicarbonate buffer (KRB; pH 7.4). Papillae were weighed (100-200 mg) in triplicate into flasks containing 3 ml KRB with 1 mM glutamine or 5 mM glucose and acetate (50 mM), propionate (25 mM), butyrate (15 mM), lactate (1 mM) and glucose (5 mM) or glutamine (1 mM) as competing substrates. A parallel set of flasks contained 1 or .5 #mu#Ci of [U-"1"4C]-glutamine or glucose respectively for "1"4CO_2 production. There were no interactions with dietary ...

1986-04-13

377

Determination of the /sup 242m/Am nuclear moments  

Energy Technology Data Exchange (ETDEWEB)

The hyperfine structure of Am atoms was investigated in an atomic beam by laser spectroscopy. The observed splittings were evaluated with respect to the magnetic dipole and electric quadrupole moments of /sup 242m/Am. The results are: ..mu../sub I/(/sup 242m/Am) = +0.97(5) nm, Q(/sup 242m/Am) = +6.5(2.0) b.

1988-07-01

379

CTX-M-14, a Plasmid-Mediated CTX-M Type Extended-Spectrum ?-Lactamase Isolated from Escherichia coli  

UK PubMed Central (United Kingdom)

Four Escherichia coli isolates harboring CTX-M-14, with a single Ala231→Val substitution compared to CTX-M-9, had three different ribotypes. Cefotaxime resistance was plasmid...Full Text Available

2002-06-01

380

Americium 242m in nuclear test debris  

International Nuclear Information System (INIS)

... americium 241 americium 242 americium 243 curium 242 environment local

381

Activation of mGluR7s Inhibits Cocaine-Induced Reinstatement of Drug-Seeking Behavior by a Nucleus Accumbens Glutamate-mGluR2/3 Mechanism in Rats  

UK PubMed Central (United Kingdom)

The metabotropic glutamate receptor 7 (mGluR7) has been reported to be involved in cocaine and alcohol self-administration. However, the role of mGluR7 in relapse to drug seeking is unknown....Full Text Available

2010-09-01

382

The quark strange star in the enlarged Nambu-Jona-Lasinio model  

Energy Technology Data Exchange (ETDEWEB)

The strange quark star is investigated within the enlarged SU(3) Nambu-Jona-Lasinio model. The stable quark star can exist until a maximal configuration with {rho}{sub m}=3.1x10{sup 15} g cm{sup -3} with M{sub m}=1.61 M{sub circle} and R{sub m}=8.74 km is reached. Strange quarks appear for density above {rho}{sub c}=9.84 g cm{sup -3} for the quark star with radius R{sub c}=8.003 km and M{sub c}=0.77 M{sub circle}. A comparison of quark star properties obtained in the quark mean-field approach to a neutron star model constructed within the relativistic mean-field theory is presented. (author)

2002-03-01

383

Redetermination of several half-lives  

International Nuclear Information System (INIS)

The half-lives of "4"1Ar, "8"0"mBr, "9"4"mNb, "1"0"1Mo, "1"0"1Tc, "1"0"9Pd, "1"0"9"mPd, "1"2"2Sb, "1"2"2"mSb, "1"2"3"mSn, "1"5"2"mEu and "2"3"9Np have been measured more accurately compared to previous measurements. All of these half-lives and 39 others published earlier will be cited by M.S. Antony in the forthcoming project 'Chart of the nuclides - Strasbourg, 1990' due to appear early 1991. (author) 34 refs.; 4 figs.; 2 tabs.

384

Mechanism of conjugated oxidation with hydrogen peroxide in presence of halide ions  

Science.gov (United States)

The change in the concentration of hydrogen peroxide in the course of its decomposition was shown, catalyzed by 0.02 M PbI/sub 2/, 0.03 M CuI, 0.02 M KI, 0.02 M FeSo/sub 4/, 6 M HCl, and 1 M HCL + 2 M H/sub 2/SO/sub 4/ at 25 C. It was suggested that in the process of the catalytic decomposition at the initial stage of the reaction, the formation of an intermediate active species containing positively charged halogen occurs; depending on the oxidative power of the counterion, the relative proportions of the hydrogen peroxide decomposing under the action of either the cation or the anion varied.

1988-01-10

385

A radioassay for Gsub(M1) ganglioside concentration in cerebrospinal fluid  

International Nuclear Information System (INIS)

A radioassay for the rapid determination of Gsub(M1) ganglioside concentration in small volumes of CSF from individual patients is described. The assay utilizes the high-affinity interaction between cholera enterotoxin ("1"2"5I-labelled) and Gsub(M1) ganglioside. The lower detection limit of Gsub(M1) ganglioside by this radioassay under the described incubation conditions is 2.5 ng/ml. The radioassay-determined lumbar CSF Gsub(M1) ganglioside concentrations in a small group of patients with diverse neurologic disorders are presented. The radioassay Gsub(M1) ganglioside concentration is in good agreement with the G(M1) ganglioside concentration determined, in one patient, by the tlc-densitometry technique. (author).

1980-01-01

386

Test results of TQS03: a LARP shell-based Nb3Sn quadrupole using 108/127 conductor  

Energy Technology Data Exchange (ETDEWEB)

Future insertion quadrupoles with large apertures and high gradients will be required for the Phase II luminosity upgrade (10{sup 35} cm{sup -2}s{sup -1}) of the Large Hadron Collider (LHC). Although improved designs, based on NbTi, are being considered as an intermediate step for the Phase I upgrade, the Nb{sub 3}Sn conductor is presently the best option that meets the ultimate performance goals for both operating field and temperature margin. As part of the development of Nb{sub 3}Sn magnet technology, the LHC Accelerator Research Program (LARP) developed and tested several 1-meter long, 90-mm aperture Nb{sub 3}Sn quadrupoles. The first two series of magnet used OST MJR 54/61 (TQ01 series) and OST RRP 54/61 (TQ02 series) strands. The third series (TQ03) used OST RRP 108/127 conductor. The larger number of sub-elements and the consequent reduction of the effective filament size, together with an increased fraction of copper and a lower Jc were expected to improve the conductor ...

2009-09-13

387

THE EVOLUTION OF THE KINEMATICS OF NEBULAR SHELLS IN PLANETARY NEBULAE IN THE MILKY WAY BULGE  

International Nuclear Information System (INIS)

We study the line widths in the [O III]#lambda#5007 and H#alpha# lines for two groups of planetary nebulae in the Milky Way bulge based upon spectroscopy obtained at the Observatorio Astronomico Nacional in the Sierra San Pedro Martir (OAN-SPM) using the Manchester Echelle Spectrograph. The first sample includes objects early in their evolution, having high H#beta# luminosities, but [O III]#lambda#5007/H#beta# < 3. The second sample comprises objects late in their evolution, with He II #lambda#4686/H#beta#>0.5. These planetary nebulae represent evolutionary phases preceding and following those of the objects studied by Richer et al. in 2008. Our sample of planetary nebulae with weak [O III]#lambda#5007 has a line width distribution similar to that of the expansion velocities of the envelopes of asymptotic giant branch stars and shifted to systematically lower values as compared to the less evolved objects studied by Richer et al. The sample with strong He II #lambda#4686 has a ...

2010-06-10

388

Spectroscopic investigation of the charge dynamics of heavy ions penetrating solid and gaseous targets  

Energy Technology Data Exchange (ETDEWEB)

This thesis presents the study of the slowing down process of fast heavy ions inside matter. In the framework of this research, the influence of the target density on the stopping process is investigated. Experiments on the interaction of {sup 48}Ca{sup 6+}-{sup 48}Ca{sup 10+} and {sup 26}Mg{sup 5+} ion beams with initial energies of 11.4 MeV/u and 5.9 MeV/u with solid and gaseous targets have been carried out. A novel diagnostic method, X-ray spectroscopy of K-shell projectile radiation, is used to determine the ion charge state in relation to its velocity during the penetration of fast heavy ions inside the stopping material. A spatially resolved analysis of the projectile and target radiation in solids is achieved for the first time. The application of low-density silica aerogels as stopping media provided a stretching of the ion stopping length by 20 - 100 times in comparison with solid quartz. The Doppler Effect observed on the projectile ...

2007-01-15

389

Reaction cross-section and reduced strong absorption radius measurements of neutron-rich nuclei in the vicinity of closed shells N=20 and N=28  

Energy Technology Data Exchange (ETDEWEB)

The energy-integrated reaction cross-sections of several neutron-rich nuclei ({sup 17-22}N, {sup 19-24}O, {sup 21-27}F, {sup 23-30}Ne, {sup 26-33}Na, {sup 28-35}Mg, {sup 31-38}Al, {sup 33-40}Si, {sup 36-42}P, {sup 39-44}S, {sup 42-45}Cl, {sup 45,46}Ar), measured at intermediate energy (30-65 A-bar MeV), via direct method, are presented. Silicon detectors have been used as the active target as well as for particles identification. The reduced strong absorption radii r{sub 0}{sup 2} are extracted and compared to the data available from the literature. New measurements for 19 nuclei ({sup 27}F, {sup 27,30}Ne, {sup 33}Na, {sup 28,34-35}Mg, {sup 36-38}Al, {sup 38-40}Si, {sup 41-42}P, {sup 42-44}S, {sup 45}Cl) are revealed. From the study of the isospin dependence of the reduced strong absorption radius, a new quadratic parameterisation of the nuclear radii in the closed shell regions N=8 and N=28, is proposed. According to this parameterisation, the proton/neutron rich ...

2006-12-11

390

Influence of anchor behaviour on the earthquake response of liquid storage tanks  

International Nuclear Information System (INIS)

The dynamic response of thin liquid storage tanks to earthquakes is a very complicated phenomenon, because it can be highly non linear. Among others, one can meet material and geometric non linearities of the tank shell leading eventually to static or dynamic buckling non linear behavior of anchor bolts, contact non-linearities due to the uplift of the tank base and to the unilateral character of the fluid pressure on the shell and high amplitude fluid oscillations. Moreover, linear or non linear soil structure interaction affects considerably the response of the fluid structure system under consideration. In this paper we focus attention on problems related only to the base uplift and anchors plastification. We study a tank similar to the Hualien project tank, but we neglect the soil structure interaction. The studied tank is representative of medium height to radius ratio ratio tanks with relatively thick bottom plate. The contact is ...

391

Five-particle, shell-model calculation using a spin-dependent potential as applied to $sup 101$Tc and the nuclear decays of $sup 101$Mo, $sup 101$Tc, $sup 142$Xe, and $sup 142$Cs  

Science.gov (United States)

Thesis. Five-particle shell-model calculations, using a spin-dependent potential, were performed for the nucleus /sup 101/Tc. The effects of varying the single-particle energy differences and the strengths of the spin-dependent and pairing terms are discussed. The isobars /sup 101/Mo and /sup 101/Tc were chemically separated to enable the detailed study of their decay schemes. As a result, 184 gamma rays were observed in the decay of /sup 101/Mo, and 169 of them were assigned to 45 levels in /sup 101/Tc. In the decay of /sup 101/Tc, 27 gamma rays were observed, and 26 of them were assigned to 11 levels in /sup 101/Ru. In a study of the decays of /sup 142/Xe and /sup 142/Cs the TRI STAN on-line isotope separator was used to separate the 142 mass chain produced in /sup 235/U fission with /sup 142/2Xe as the emanating and accelerated nuclide. Isobaric separation of /sup 142/Xe and /sup 142/Cs was achieved with a moving tape system. ...

1974-03-01

392

Effect of pitting corrosion on local strength of hold frames of bulk carriers (1st report)  

Energy Technology Data Exchange (ETDEWEB)

Firstly, pitting corrosion observed on hold frames in cargo holds of bulk carriers which exclusively carry coal and iron ore has been investigated in detail. It was shown that the shape of the corrosion pits observed on them is a circular cone and the ratio of the diameter to the depth is in the range between 8 to 1 and 10 to 1, which is different from the trend observed for the bottom shell of the oil tanker where the ratio is in the range between 4 to 1 and 6 to 1. Secondly, a series of tensile tests has been conducted to investigate the effect of pitting corrosion on tensile strength of members. It was pointed out that the tensile strength decreases gradually and the total elongation decreases drastically with the increase of the thickness loss due to pitting corrosion. The reduction of the tensile strength of the members with pitting corrosion is larger than that of members with uniform thickness loss in terms of average thickness loss. Thirdly, a series of ...

2004-09-01

393

Diagnostics aid for mass spectrometer trouble-shooting  

International Nuclear Information System (INIS)

The MS Expert system provides problem diagnostics for instruments used in the Mass Spectrometry Laboratory (MSL). The most critical results generated on these mass spectrometers are the uranium concentration and isotopic content data used for process control and materials accountability at the Idaho General Processing Plant. The two purposes of the system are: (1) to minimize instrument downtime and thereby provide the best possible support to the Plant, and (2) to improve long-term data quality. This system combines the knowledge of several experts on mass spectrometry to provide a diagnostic tool, and can make these skills available on a more timely basis. It integrates code written in the Pascal language with a knowledge base entered into a commercial expert system shell. The user performs some preliminary status checks, and then selects from among several broad diagnostic categories. These initial steps provide input to the rule base. The overall analysis ...

394

Decay of "1"0"1Mo and band structures of its daughter nuclide "1"0"1Tc in the projected shell model  

International Nuclear Information System (INIS)

The decay of molybdenum-101 has been investigated using the three-parameter (#gamma#-#gamma#-t) coincidence system of HPGe-HPGe detectors. According to the off-line analysis, the decay scheme was modified. The positions of 221.80, 318.00, 377.90; 452.50, 515.42, 1011.05, and 1759.72 keV transitions have been arranged again, the transition positions of 104.70, 105.95, and 774.15 keV gamma rays have been assigned for the first time, the positions of 169.00, 590.91, 980.52, and 1431.68 keV transitions have been reconfirmed, and the 1508.01 keV gamma ray was observed simultaneously for the first time and its transition position has been assigned. The #beta#"- intensities and the values of log ft of most levels were calculated. Combining with the high-spin states observed by the in-beam #gamma#-ray spectroscopy of previous decay works, the structure of the excited positive/negative-parity yrast states of "1"0"1Tc is discussed using a projected shell model, and a band ...

2006-01-01

395

Corrosion studies of carbon steel under impinging jets of simulated slurries of neutralized current acid waste (NCAW) and neutralized cladding removal waste (NCRW)  

Energy Technology Data Exchange (ETDEWEB)

Plans for the disposal of radioactive liquid and solid wastes presently stored in double-shell tanks at the Hanford Site call for retrieval and processing of the waste to create forms suitable for permanent disposal. Waste will be retrieved from a tank using a submerged slurry pump in conjunction with one or more rotating slurry jet mixer pumps. Pacific Northwest Laboratory (PNL) has conducted tests using simulated waste slurries to assess the effects of a impinging slurry jet on the corrosion rate of the tank wall and floor, an action that could potentially compromise the tank's structural integrity. Corrosion processes were investigated on a laboratory scale with a simulated neutralized cladding removal waste (NCRW) slurry and in a subsequent test with simulated neutralized current acid waste (NCAW) slurry. The test slurries simulated the actual NCRW and NCAW both chemically and physically. The tests simulated those conditions expected to exist in the ...

1992-01-01

396

Corrosion studies of carbon steel under impinging jets of simulated slurries of neutralized current acid waste (NCAW) and neutralized cladding removal waste (NCRW)  

Energy Technology Data Exchange (ETDEWEB)

Plans for the disposal of radioactive liquid and solid wastes presently stored in double-shell tanks at the Hanford Site call for retrieval and processing of the waste to create forms suitable for permanent disposal. Waste will be retrieved from a tank using a submerged slurry pump in conjunction with one or more rotating slurry jet mixer pumps. Pacific Northwest Laboratory (PNL) has conducted tests using simulated waste slurries to assess the effects of a impinging slurry jet on the corrosion rate of the tank wall and floor, an action that could potentially compromise the tank`s structural integrity. Corrosion processes were investigated on a laboratory scale with a simulated neutralized cladding removal waste (NCRW) slurry and in a subsequent test with simulated neutralized current acid waste (NCAW) slurry. The test slurries simulated the actual NCRW and NCAW both chemically and physically. The tests simulated those conditions expected to exist in the respective ...

1992-01-01

397

Benchmark Analysis of Subcritical Noise Measurements on a Nickel-Reflected Plutonium Metal Sphere  

Energy Technology Data Exchange (ETDEWEB)

Subcritical experiments using californium source-driven noise analysis (CSDNA) and Feynman variance-to-mean methods were performed with an alpha-phase plutonium sphere reflected by nickel shells, up to a maximum thickness of 7.62 cm. Both methods provide means of determining the subcritical multiplication of a system containing nuclear material. A benchmark analysis of the experiments was performed for inclusion in the 2010 edition of the International Handbook of Evaluated Criticality Safety Benchmark Experiments. Benchmark models have been developed that represent these subcritical experiments. An analysis of the computed eigenvalues and the uncertainty in the experiment and methods was performed. The eigenvalues computed using the CSDNA method were very close to those calculated using MCNP5; however, computed eigenvalues are used in the analysis of the CSDNA method. Independent calculations using KENO-VI provided similar eigenvalues to those determined using the ...

2009-09-01

398

The (N,M)-th KdV hierarchy and the associated W algebra  

International Nuclear Information System (INIS)

We discuss a differential integrable hierarchy, which we call the (N, M)-th KdV hierarchy, whose Lax operator is obtained by properly adding M pseudo-differential terms to the Lax operator of the N-th KdV hierarchy. This new hierarchy contains both the higher KdV hierarchy and multi-field representation of KP hierarchy as sub-systems and naturally appears in multi-matrix models. The (N+2M-1) coordinates or fields of this hierarchy satisfy two algebras of compatible Poisson brackets which are local and polynomial. Each Poisson structure generate an extended W_1_+_#infinity# and W_#infinity# algebra, respectively. We call W (N, M) the generating algebra of the extended W_#infinity# algebra. This algebra, which corresponds with the second Poisson structure, shares many features of the usual W_N algebra. We show that there exist M distinct reductions of the (N, ...

1993-01-01

399

Studies of wind profile and estimation of surface layer scaling parameters for the coastal site of Tarapur  

International Nuclear Information System (INIS)

This paper presents the directional dependence of surface scaling parameters namely roughness length and corresponding friction velocity, for neutral category of Tarapur coastal site. The average roughness length of lowest value of 0.07 m (SW) and the highest value of 0.32 m (E) and average friction velocity of lowest value 1.6 m/sec(SSE) and a highest value 2.8 m/sec (SW) for the year 2006 were observed. Wind profile studies for the coastal site Tarapur with the wind data measured from meteorological tower of 30m which is at 1500m downwind fetch distance from the coastal line in the east direction gave the wind profile index parameter 'p' as 0.4, 0.5 and 0.75 for Unstable, Neutral and Stable weather conditions respectively. Sector Average Turbulent kinetic energy estimated as 17.7m2/s2 and its dissipation rate is 3.1 ...

2007-06-05

400

Insulin affects the sodium affinity of the rat adipocyte (Na ,K )-ATPase  

Energy Technology Data Exchange (ETDEWEB)

The K0.5 for intracellular sodium of the two forms of (Na ,K )-ATPase which exist in rat adipocytes has been determined by incubating the cells in the absence of potassium in buffers of varying sodium concentration; these conditions shut off the Na pump and allow sodium to equilibrate into the cell. The activity of (Na ,K )-ATPase was then monitored with YWRb /K pumping which was initiated by adding isotope and KCl to 5 mM, followed by a 3-min uptake period. Atomic absorption and SSNa tracer equilibration were used to determine the actual intracellular (Na ) under the different conditions. The K0.5 values thus obtained were 17 mM for alpha and 52 mM for alpha(+). Insulin treatment of rat adipocytes had no effect on the intracellular (Na+) nor on the Vmax of YWRb /K pumping, but did produce a shift in the sodium ion K0.5 values to 14 mM for alpha and 33 mM for alpha(+). This change ...

1985-08-25

401

Anodic Protection performance of Steels ASTM A 516-60 And JIS G 3131 SPHC In Concentrated Sulfuric Acid  

International Nuclear Information System (INIS)

One of the methods to protect a carbon steel material from corrosion attack of sulfuric acid environment is with anodic protection. This research was intended to investigate the effect of anodic protection quickened with potential polarization, The material under investigation were ASTM A 516 and JIS G 3131-SPHC in highly concentrated H_2SO_4 solution. The results showed that potential that was effective for anodic protection in ASTM A 516-60 were at 236-436 mV for 75%, 276-476 mV for 80%, 264-514 mV for 85%,285-485 mV for 90%, and 231-431 mV for 97% H_2SO_4 so that in JlS G 3131-SPHC were at 303 -503 mV for 75%, 290-490 mV for 80%, 269- 516 mV for 85%, 264-514 mV for 90%, and 287 -487 mV for 97% H_2SO_4.

2001-06-01

402

School of Earth and Environment  

Wastenet

...Verheggen, B; Dommen, J; Duplissy, J; Prevot, AS; Weingartner, E; Riipinen, I; Kulmala, M; Spracklen, DV; Carslaw, KS; ...Carslaw, KS; Boucher, O; Spracklen, DV; Mann, GW; Rae, JGL; Woodward, S; Kulmala, M (2010) A review of natural aerosol interactions ...Pickering, S; Ogren, JA; Andrews, E; Baltensperger, U; Weingartner, E; Boy, M; Kulmala, M; Laakso, L; Lihavainen, H; ...Fastrup, B; Gagne, S; Hahn, F; Harrison, RG; Kellett, B; Kirkby, J; Kulmala, M; Laakso, L; Laaksonen, A; ...

403

A QUINTET OF BLACK HOLE MASS DETERMINATIONS  

International Nuclear Information System (INIS)

We report five new measurements of central black hole masses based on Space Telescope Imaging Spectrograph and Wide Field Planetary Camera 2 observations with the Hubble Space Telescope (HST) and on axisymmetric, three-integral, Schwarzschild orbit-library kinematic models. We selected a sample of galaxies within a narrow range in velocity dispersion that cover a range of galaxy parameters (including Hubble type and core/power-law surface density profile) where we expected to be able to resolve the galaxy's sphere of influence based on the predicted value of the black hole mass from the M-#sigma# relation. We find masses for the following galaxies: NGC 3585, M _B_H = 3.4"+"1"."5 _-_0_._6 x 10"8 M _s_u_n; NGC 3607, M _B_H = 1.2"+"0"."4 _-_0_._4 x 10"8 M _s_u_n; NGC 4026, M _B_H = 2.1"+"0"."7 _-_0_._4 x 10"8 M _s_u_n; and NGC 5576, ...

2009-04-20

404

A low-temperature calorimetric study of synthetic (forsterite+fayalite) {(Mg2SiO4+Fe2SiO4)} solid solutions: An analysis of vibrational, magnetic, and electronic contributions to the molar heat capacity and entropy of mixing  

International Nuclear Information System (INIS)

The molar heat capacities (Cp,m) of a series of synthetic forsterite (Fo)-fayalite (Fa), (Mg2SiO4+Fe2SiO4), olivines have been measured between 5K and 300K on milligram-sized samples with the Physical Properties Measurement System (Quantum Design(R)). Sharp, ?-type heat capacity anomalies are observed in the Fe-rich compositions fayalite, Fo10Fa90, Fo20Fa80, Fo30Fa70, and Fo40Fa60. The corresponding Neel temperatures TN decrease linearly from 64.5K in fayalite to 32.8K in Fo40Fa60 following the relationship TN=79.02.xFa-14.07. Fo50Fa50 and Mg-richer olivines show weak broad features in the heat capacity data around 15K to 20K that decrease in magnitude with increasing forsterite content. In order to derive and separate molar electronic, magnetic and vibrational heat capacity contributions, Cel,m, Cmag,m, and Cvib,m from the experimental heat capacities (Ctot,m), we used a ...

2007-06-01

405

High-frequency microseismicity in the rock salt of the Asse mine around the 945 m level; Hochfrequenz Mikroseismizitaet im Steinsalz der Asse um den 945-m-Bereich  

Energy Technology Data Exchange (ETDEWEB)

3407 events were registrated up to a distance of 300 m during the period from 12.10.1989 to 31.12.1990, of which 385 could be precisely located. Activities were determined in areas surrounding the dam construction traversal drifts and boreholes at the 875 m level, near the large cavern at 975 m depth, in drifts and caverns above the 875 m level and in the vicinity of the rock salt/carnallitite transition zone to the south-east of the 875 m level. Energies and source parameters were calculated by means of spectres. Energy variations range from 10 J to 10{sup -4} J, the source radii from 3.5 m to 0.2 m, the source dislocations from 10{sup -6} m to 10{sup -8} m, and the stress drops from 10{sup 5} Pa to 0.06 10{sup 5} Pa. Magnitude and type of events observed are usual for mines. The microseismic ...

1991-11-01

406

The nucleation kinetics of calcium sulfate dihydrate in NaCl solutions up to 6 m and 90 C  

Energy Technology Data Exchange (ETDEWEB)

The crystallization of calcium sulfate from aqueous solutions with NaCl is both geological and industrial interest because NaCl is the dominant solute in natural brines and many industrial fluids. Induction periods for the nucleation of calcium sulfate dihydrate were experimentally determined as a function of supersaturation in NaCl solutions from 0 to 6 m at 25 C and in 3.0-m NaCl solutions at temperatures from 25 to 90 C. Using classic nucleation theory, the interfacial tension between gypsum and 3.0-m NaCl solution was estimated to be about 39 mJ/m[sup 2] at 25 C and increases with increasing temperature (to 63 mJ/m[sup 2] at 90 C). It was observed that the induction period decreases with increasing NaCl concentrations up to 3 m and then starts to increase slightly at a given temperature and saturation state. The electrolyte effect on nucleation was ...

1994-02-01

407

The lightest Higgs Boson of mSUGRA, mGMSB and mAMSB at Present and Future Colliders Observability and Precision Analyses  

CERN Document Server

We investigate the physics of the lightest CP-even MSSM Higgs boson at the Tevatron, the LHC, a linear e+e- collider, a gamma gamma collider and a mu+mu- collider. The analysis is performed in the three most prominent soft SUSY-breaking scenarios, mSUGRA, mGMSB and mAMSB. For all colliders the observability and parameter regions with suppressed production cross sections (compared to a SM Higgs boson with the same mass) are investigated. For the lepton and photon colliders the potential is analyzed of precision measurements of the branching ratios of the light CP-even Higgs boson for obtaining indirect bounds on the mass of the CP-odd Higgs boson and the high-energy parameters of the soft SUSY-breaking scenarios. In regions of the parameter space where the LHC can detect the heavy Higgs bosons, precision measurements of the properties of the light Higgs boson at the linear collider can provide valuable information for ...

2003-01-01

408

Supersymmetric renormalisation group fixed points and third generation fermion mass predictions  

Energy Technology Data Exchange (ETDEWEB)

We present a supersymmetric renormalization group fixed point determination of the third generation fermion masses, in which the large mass ratio between the top and bottom quarks is attributed to a hierarchy in the vacuum expectation values of the two Higgs doublets. Above a supersymmetry breaking scale, M{sub s}, we use the minimal supersymmetric standard model with a transition at M{sub s} to the standard model with only one Higgs- doublet effective. The mass predictions result from renormalization group evolution of large Yukawa couplings at M{sub x} {approximately} 1016 GeV. Averaging over a wide range of these couplings, not subject to any symmetry requirements, gives m{sub t} = 184.3{plus_minus}6.8 GeV, m{sub b} = 4.07{plus_minus}0.33 GeV, m{sub {tau}} = 1.78{plus_minus}0.33 GeV and a light Higgs mass m{sub h}o = 121.8{plus_minus}4.3 ...

1992-09-01

409

Generalized support varieties for finite group schemes  

CERN Document Server

We construct two families of refinements of the (projectivized) support variety of a finite dimensional module $M$ for a finite group scheme $G$. For an arbitrary finite group scheme, we associate a family of {\\it non maximal rank varieties} $\\Gamma^j(G)_M$, $1\\leq j \\leq p-1$, to a $kG$-module $M$. For $G$ infinitesimal, we construct a finer family of locally closed subvarieties $V^{\\ul a}(G)_M$ of the variety of one parameter subgroups of $G$ for any partition $\\ul a$ of $\\dim M$. For an arbitrary finite group scheme $G$, a $kG$-module $M$ of constant rank, and a cohomology class $\\zeta$ in $\\HHH^1(G,M)$ we introduce the {\\it zero locus} $Z(\\zeta) \\subset \\Pi(G)$. We show that $Z(\\zeta)$ is a closed subvariety, and relate it to the non-maximal rank varieties. We also extend the construction of $Z(\\zeta)$ to an arbitrary ...

2011-01-01

410

Gelatin ablation wavelength dependency in the range of 5.6-6.7 #mu#m using a mid-infrared Free Electron Laser  

International Nuclear Information System (INIS)

Efficient and precise ablation of soft tissue is needed for non-invasive dermatological and corneal surgeries. Previous research has revealed that smooth and efficient cutting of certain soft tissues and gelatin is possible using a Free Electron Laser (FEL) with a wavelength of #lambda#=6.45 #mu#m, tuned to the amide-II band of protein. Gelatin ablation experiments have been carried out using a mid-infrared FEL within the waveband #lambda#=5.6-6.7 #mu#m by changing the primary absorbers such as water (#lambda#=6.1 #mu#m) and protein (#lambda#=6.45 #mu#m). The gelatin with 80 wt% water was efficiently ablated by FEL irradiation with the waveband #lambda#=#approx#5.95-6.19 #mu#m. On the other hand, using irradiation within #lambda#=#approx#6.4-6.6 #mu#m, many small bubbles were observed in the irradiated volume, and the gelatin was not ablated but significantly ...

2003-07-11

411

Determination of radiochemical purity and pharmacokinetic parameters of sup(99m)Tc-sulphur colloid and sup(99m)Tc-tin colloid  

Energy Technology Data Exchange (ETDEWEB)

Labelling yield and radiochemical purity, higher than 95%, of sup(99m)Tc-colloid preparations were determined by using the paper chromatography method. Less than 3% of labelled citric acid, added to the preparation as a buffer solution, has been found in sup(99m)Tc-sulphur colloid. High radiochemical purity and optimum size of colloid particles has also been proved by biodistribution studies on experimental animals. The analysis performed has shown that more than 50% of sup(99m)Tc-colloid preparations excreted by urine is sup(99m)TcO/sup -/, the remaining past 50% being protein bound sup(99m)Tc. Biological half-time of excretion of the fast phase is the same for both preparations, i.e. 10 min, while for the slow component it is 120 min in sup(99m)Tc-S-colloid and 160 min in sup(99m)Tc-Sn colloid.

1981-12-01

412

Correlation between proton pumping and the bacteriorhodopsin photocycle  

Energy Technology Data Exchange (ETDEWEB)

In an attempt to establish a relationship between proton pumping and the photocycle intermediates of bacteriorhodopsin, we have studied the effects of pH and temperature of flash-induced proton pumping and the photointermediates O/sub 640/ and M/sub 412/. The relative quantum yield of flash-induced proton pumping is both pH and temperature dependent. It is high in the acid pH range and at low temperatures but decreases in the basic pH range and at high temperatures. The decay of M/sub 412/ is biphasic. The amplitude of the slowly decaying component (M/sup s/) was found to be pH dependent with a pK similar to that of the ..delta..pH. The pH dependence of the fast-decaying component (M/sup f/) is opposite to that of M/sup s/ and ..delta..pH. Like that of M/sup s/, the amplitude of O/sub 640/ is high in the acid pH range, but unlike the amplitude of ...

1984-11-01

413

An EXAFS investigation of the structures of bromocopper(II) complexes in some solutions  

International Nuclear Information System (INIS)

The structures of bromocopper(II) complexes in methanolic (M1, M2, M3, M4), ethanolic (E), and aqueous (H) solutions were determined by the analyses of the Cu K- and Br K-edge EXAFS spectra using a curve-fitting method. The molar concentrations of Cu and Br in these solutions prepared by CuBr_2 and LiBr are 0.996 and 1.992 (M1), 1.015 and 5.381 (M2), 0.493 and 4.525 (M3), 0.260 and 4.073 (M4), 1.031 and 4.313 (E), and 0.982 and 5.426 (H). In M1 solution the interatomic distances for the Cu-O_e_q, Br_e_q-Cu, and Br_e_q-O_e_q (_e_q = equatorial) were 2.00A, 2.35A, and 3.15A respectively, and the Br_e_q-Cu-O_e_q angle was estimated as about 92 deg. Therefore, trans-dibromo bis(methanol)copper(II) complex with a slightly distorted planar structure was proposed to be dominant complex species in ...

414

Application of low-dose radiation protocols in survey CT scans  

International Nuclear Information System (INIS)

Objective: To characterize the protocols with low-dose radiation in survey CT scans for localization. Methods: Eighty standard adult patients, head and body phantoms were recruited. Default protocols provided by operator's manual setting were that all the tube voltage for head, chest, abdomen and lumbar was 120 kV; the tube currents were 20,10,20 and 40 mA, respectively. Values of kV and mA in the low-dose experiments were optimized according to the device options. For chest and abdomen, the tube position were compared between default (0 degree) and 180 degree. Phantoms were scanned with above protocols, and the radiation doses were measured respectively. Paired t-test were used for comparisons of standard deviation in CT value, noise and exposure surface dose (ESD) between group with default protocols and group with optimized protocols. Results: The optimized protocols in low-dose CT survey scans were 80 kV, 10 mA for ...

2009-08-01

415

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

416

Complete genome sequences of Brucella melitensis strains M28 and M5-90, with different virulence backgrounds.  

Science.gov (United States)

Brucella melitensis is a Gram-negative coccobacillus bacteria belonging to the Alphaproteobacteria subclass. It is an important zoonotic pathogen that causes brucellosis, a disease affecting sheep, cattle, and sometimes humans. The B. melitensis strain M5-90, a live attenuated vaccine cultured from the B. melitensis virulent strain M28, has been an effective tool to control brucellosis in goats and sheep in China. Here we report the complete genome sequences of B. melitensis M28 and M5-90, strains with different virulence backgrounds, which will serve as a valuable reference for future studies. PMID:21478357

2011-04-08

417

Analysis of organic acids in the pyrohydrolysis distillate of (U,Pu) mixed carbide fuel by ion chromatography  

International Nuclear Information System (INIS)

The study reports the identification of different organic acids that are formed during the pyrohydrolysis of mixed carbide of uranium and plutonium using ion chromatography (IC). The identification of organic acids present in the pyrohydrolysis distillate is required to carry out interference free analysis of Cl and F. The study describes three stage isocratic separations with NaOH eluents having concentrations 2 mM, 10 mM and 50 mM respectively in order to separate and identify both aliphatic and aromatic acids. The present investigation identified formic, acetic, propionic, butyric, tartaric and oxalic acids in the distillate, however, aromatic acids could not be identified. (author)

2011-02-22

418

Adiabatic matter effect with three generation neutrinos and the solar neutrino problem  

CERN Document Server

We find an exact analytic solution for the time evolution of a three Dirac neutrino system adiabatically oscillating in matter, constructing explicitly the relevant 3\\times 3 mixing matrix in matter. Using this result we investigate the solar neutrino data in a scenario where the neutrino masses are such that m_1\\alt m_2\\ll m_3, taking into account several phenomenological constraints on neutrino mixing angles and masses. A solution of the solar neutrino problem for large values of the parameter \\delta m^2=m_2^2-m_1^2 which are not usually associated with a resonance is found. This is an essentially three-generation effect.

1994-01-01

419

In vitro and in vivo study of {sup 99m}Tc-MIBI encapsulated in PEG-liposomes: a promising radiotracer for tumour imaging  

Energy Technology Data Exchange (ETDEWEB)

Encapsulation of technetium-99m sestamibi ({sup 99m}Tc-MIBI) in polyethyleneglycol-liposomes ({sup 99m}Tc-MIBI-PEG-liposomes) could extend the duration of its circulation in blood and alter its biodistribution, enabling its concentration in tumours to be increased. An original method to encapsulate {sup 99m}Tc-MIBI in PEG-liposomes is described. The {sup 99m}Tc-MIBI-PEG-liposomes were compared with free {sup 99m}Tc-MIBI with respect to (a) tumour availability (b) ability to distinguish between chemotherapy-sensitive and -resistant cells and (c) uptake ratio in tumour imaging. PEG-liposomal systems composed of distearoylphosphatidylcholine/cholesterol/PEG{sub 2000}-distearoyl phosphatidylethanolamine and lissamine-rhodamine B-labelled liposomes were used. The encapsulation of {sup 99m}Tc-MIBI in liposomes was achieved using the K{sup +} ...

2003-04-01

420

THE M-#sigma# AND M-L RELATIONS IN GALACTIC BULGES, AND DETERMINATIONS OF THEIR INTRINSIC SCATTER  

International Nuclear Information System (INIS)

We derive improved versions of the relations between supermassive black hole mass (M _B_H) and host-galaxy bulge velocity dispersion (#sigma#) and luminosity (L; the M-#sigma# and M-L relations), based on 49 M _B_H measurements and 19 upper limits. Particular attention is paid to recovery of the intrinsic scatter (#epsilon#_0) in both relations. We find log(M _B_H/M _s_u_n) = #alpha# + #beta#log(#sigma#/200 km s"-"1) with (#alpha#, #beta#, #epsilon#_0) = (8.12 #+-# 0.08, 4.24 #+-# 0.41, 0.44 #+-# 0.06) for all galaxies and (#alpha#, #beta#, #epsilon#_0) = (8.23 #+-# 0.08, 3.96 #+-# 0.42, 0.31 #+-# 0.06) for ellipticals. The results for ellipticals are consistent with previous studies, but the intrinsic scatter recovered for spirals is significantly larger. The scatter inferred reinforces the need for its consideration when calculating local black hole mass ...

2009-06-10

421

Activation analysis of trace elements in titanium-molybdate target used for pre-formed TiMo gel based "9"9"mTc generator production and radionuclidic impurity of "9"9"mTc pertechnetate eluate  

International Nuclear Information System (INIS)

A gel-type "9"9Mo-"9"9"mTc generator using Titanium-Molybdate target (TiMo-target) as column packing was developed in Radioisotope Department, the Dalat Nuclear Research Institute [1]. The concentration of trace elements in TiMo-target and radionuclidic purity in "9"9"mTc solution eluted from this type of generator were studied for quality control purpose. The monostandard method in neutron activation analysis has been applied to determine the concentration of trace impurities in titanium-molybdate target. For neutron activation analysis, TiMo samples were irradiated in the different channels of nuclear reactor IVV-9 at a neutron flux of maximum 2.1 x 10"1"3 n.cm"-"2s"-"1. The following chemical element impurities were determined: Na, W, Co, Fe, Zn, Ag, Sb and Cr. The gamma ray emitted nuclides found in "9"9"mTc solution eluted from our "9"9"mTc generator were the following: "6"5Zn, "6"0Co, ...

2004-06-01

422

Virulence Factors of Escherichia coli Isolates That Produce CTX-M-Type Extended-Spectrum ?-Lactamases  

UK PubMed Central (United Kingdom)

This study determined the phylogenetic groups and virulence factors of 37 Escherichia coli isolates producing types of CTX-M compared with those of 19 isolates producing different types...Full Text Available

2005-11-01

423

The 17-M VAWT program  

Science.gov (United States)

The commercial potential of the 17 m, 100 kW Darrieus Vertical Axis Wind Turbine (VAWT) is discussed. Long term testing is in progress. As the first commercially adapted Darrieus turbines built by DOE, the superior cost, structural integrity, and output characteristics demonstrated by the prototypes appear particularly promising.

1981-01-01

424

Survey for Transiting Extrasolar Planets in Stellar Systems. II. Spectrophotometry and Metallicities of Open Clusters  

CERN Document Server

We present metallicity estimates for seven open clusters based on spectrophotometric indices from moderate-resolution spectroscopy. Observations of field giants of known metallicity provide a correlation between the spectroscopic indices and the metallicity of open cluster giants. We use \\chi^2 analysis to fit the relation of spectrophotometric indices to metallicity in field giants. The resulting function allows an estimate of the target-cluster giants' metallicities with an error in the method of \\pm0.08 dex. We derive the following metallicities for the seven open clusters: NGC 1245, [m/H]=-0.14\\pm0.04; NGC 2099, [m/H]=+0.05\\pm0.05; NGC 2324, [m/H]=-0.06\\pm0.04; NGC 2539, [m/H]=-0.04\\pm0.03; NGC 2682 (M67), [m/H]=-0.05\\pm0.02; NGC 6705, [m/H]=+0.14\\pm0.08; NGC 6819, [m/H]=-0.07\\pm0.12. These metallicity ...

2005-01-01

425

Subunits of the Drosophila CCR4-NOT complex and their roles in mRNA deadenylation  

UK PubMed Central (United Kingdom)

The CCR4-NOT complex is the main enzyme catalyzing the deadenylation of mRNA. We have investigated the composition of this complex in Drosophila melanogaster by immunoprecipitation...Full Text Available

2010-07-01

426

Spectrophotometry of H II regions in the spiral galaxy M101  

Energy Technology Data Exchange (ETDEWEB)

Spectral line intensity data are presented for ionized hydrogen regions in the giant spiral galaxy M101. The influence of interstellar extinction is assessed and electron temperatures of the gas clouds are derived.

1981-04-01

427

Sodium ion-dependent amino acid transport in membrane vesicles of Bacillus stearothermophilus.  

UK PubMed Central (United Kingdom)

Amino acid transport in membrane vesicles of Bacillus stearothermophilus was studied. A relatively high concentration of sodium ions is needed for uptake of L-alanine (Kt = 1.0 mM) and L-leucine (Kt...Full Text Available

1991-01-01

428

Signal transduction underlying the control of urinary bladder smooth muscle tone by muscarinic receptors and ?-adrenoceptors  

UK PubMed Central (United Kingdom)

The normal physiological contraction of the urinary bladder, which is required for voiding, is predominantly mediated by muscarinic receptors, primarily the M3 subtype, with the M2...Full Text Available

2008-06-01

429

Seasonal and Regional Dynamics of M. ulcerans Transmission in Environmental Context: Deciphering the Role of Water Bugs as Hosts and Vectors  

UK PubMed Central (United Kingdom)

BackgroundBuruli ulcer, the third mycobacterial disease after tuberculosis and leprosy, is caused by the environmental mycobacterium M. ulcerans. Various modes of...Full Text Available

430

Role of sodium in the growth of a ruminal selenomonad.  

UK PubMed Central (United Kingdom)

The ruminal selenomonad strain H18 grew rapidly (mu = 0.50 h-1) in a defined medium containing glucose, ammonia, purified amino acids, and sodium (95 mM); little if any ammonia was utilized as a nitrogen...Full Text Available

1991-06-01

431

RefLexiones sobre la inmensidad del universo.La materia vista desde la Grecia antigua hasta la era m  

CERN Document Server

RefLexiones sobre la inmensidad del universo.La materia vista desde la Grecia antigua hasta la era m

2009-01-01

432

Recent changes in the epidemiology and management of extended-spectrum ?-lactamase-producing Enterobacteriaceae  

UK PubMed Central (United Kingdom)

Since 2000, Escherichia coli producing CTX-M enzymes (especially CTX-M-15) have emerged worldwide as important causes of community-onset urinary tract and blood stream infections due...Full Text Available

433

RESPONSE OF THE ARCTIC FRESHWATER BUDGET TO EXTREME NAO - ECCO2 - NASA  

Science.gov (United States)

... J. Rolph, S. J. Camargo, K. L. Gleason, M. J. Salinger, A. B. Watkins, ... C . Kocot, D. Phillips, R. Whitewood, M. O. Vazquez, E. K. Grover-Kopec, ...

434

Purification of mRNA guanylyltransferase from calf thymus.  

UK PubMed Central (United Kingdom)

mRNA guanylyltransferase has been extensively purified from calf thymus. A GTP-binding assay was used based on the observations by Shuman and Hurwitz (1981) and Venkatesan and Moss (1982) that vaccinia...Full Text Available

1982-01-01

435

Pubs.GISS: Ghil et al. 1977: A balanced ... - Publications - NASA  

Science.gov (United States)

Ghil, M., B. Shkoller, and V. Yangarber, 1977: A balanced diagnostic system compatible with a barotropic prognostic model. M. Weather. Rev. , 105, 1223- 1238, ...

436

Processing L0 to L2 250m TSM - Ocean Color - NASA  

Science.gov (United States)

I was wondering if someone could please help me out with the steps involved to process MODIS L0 data to 250m res TSM data using a ...

437

Presence of two independent chromosomes in the Brucella melitensis 16M genome.  

UK PubMed Central (United Kingdom)

Mapping the restriction fragments of the Brucella melitensis 16M genome with a new restriction endonuclease, PacI, which cut the DNA into only eight fragments, indicated that this species contains two...Full Text Available

1993-02-01

438

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 $f^*h|_HM,g_H)\\to (N,h)$ which is $C^0$-close to $f_0$. In particular we prove that every sub-Riemannian manifold $(M,H,g_H)$ admits a partial isometry in $\\R^n$ provided $n\\geq ...

2010-01-01

439

ONERA M6 Wing - NASA  

Science.gov (United States)

Jul 8, 2008 ... This case involves the flow over the ONERA M6 wing. ... The wind tunnel tests are documented by Schmitt and Charpin in the AGARD Report AR-138 ... supersonic flow, shocks, and turbulent boundary layers separation). ...

440

MicroRNAs and small interfering RNAs can inhibit mRNA expression by similar mechanisms  

UK PubMed Central (United Kingdom)

MicroRNAs (miRNAs) are endogenously encoded small noncoding RNAs, derived by processing of short RNA hairpins, that can inhibit the translation of mRNAs bearing partially complementary target sequences....Full Text Available

2003-08-19

441

Methanogen Diversity Evidenced by Molecular Characterization of Methyl Coenzyme M Reductase A (mcrA) Genes in Hydrothermal Sediments of the Guaymas Basin  

UK PubMed Central (United Kingdom)

The methanogenic community in hydrothermally active sediments of Guaymas Basin (Gulf of California, Mexico) was analyzed by PCR amplification, cloning, and sequencing of methyl coenzyme M reductase...Full Text Available

2005-08-01

442

Mean glandular doses for women undergoing mammographic breast screening in Oyo state, Nigeria  

British Library Electronic Table of Contents (United Kingdom)

In this work, thermoluminescent dosimeters have been used to measure entrance surface doses (ESDs) of patients undergoing mammographic screening at the University College Hospital, Ibadan, Oyo state. The mean glandular doses (MGDs) were also calculated using the measured ESDs. The results showed that the ESDs ranged from 0.26mGy to 21.26mGy for the mediolateral oblique (MLO) views and 0.08mGy to 5.36mGy for the craniocaudal (CC) views. The calculated MGD ranged from 0.07mGy to 3.57mGy for the MLO views and 0.02mGy to 0.98mGy for the CC views. The possible reasons for the large variations in the individual ESD values and MGD values for both views are discussed using patients data, equipment specific data and the technical parameters used for the examinations. Comparison showed that the mean...

2009-01-01

443

Making the message clear: visualizing mRNA localization  

UK PubMed Central (United Kingdom)

Localized mRNA provides spatial and temporal protein expression essential to cell development and physiology. To explore the mechanisms involved, considerable effort has been spent in establishing new...Full Text Available

2010-07-01

444

MSFC ESO Applied ... - Global Hydrology and Climate Center - NASA  

Science.gov (United States)

In the IEEE Marine Technology Society OCEANS 2009 Conference, Biloxi. October 26-29, 2009. Biloxi, MS. Al-Hamdan, M.; Estes, M.; Quattrochi, D.; Thom, R.; ...

445

J4P Evaluation of Externally Heated Pulsed MPD Thruster Cathodes  

Science.gov (United States)

twenty 350 V, 2.5 mF aluminum electrolytic capacitors with 10.8 mH inductors made of multi-strand wire. The PFN discharge was controlled using an silicon ...

446

Identification of CTX-M-Type Extended-Spectrum-?-Lactamase Genes Using Real-Time PCR and Pyrosequencing?  

UK PubMed Central (United Kingdom)

CTX-M extended-spectrum β-lactamases (ESBLs) are increasingly prevalent worldwide among Escherichia coli bacteria, mostly in community-acquired urinary tract infections. Finding...Full Text Available

2007-01-01

447

Identification of CTX-M-14 Extended-Spectrum ?-Lactamase in Clinical Isolates of Shigella sonnei, Escherichia coli, and Klebsiella pneumoniae in Korea  

UK PubMed Central (United Kingdom)

CTX-M-14 β-lactamase was identified in a stool isolate of Shigella sonnei and in blood isolates of Escherichia coli (one isolate) and Klebsiella pneumoniae...Full Text Available

2001-10-01

448

Functional Analysis of the Murine Cytomegalovirus Chemokine Receptor Homologue M33: Ablation of Constitutive Signaling Is Associated with an Attenuated Phenotype In Vivo?  

UK PubMed Central (United Kingdom)

The murine cytomegalovirus (MCMV) M33 gene is conserved among all betaherpesviruses and encodes a homologue of seven-transmembrane receptors (7TMR) with the capacity for constitutive signaling. Previous...Full Text Available

2008-02-01

449

Evaluating the performance of wind turbines in selected locations in Oyo state, Nigeria  

British Library Electronic Table of Contents (United Kingdom)

The wind speed distribution and wind energy potential are investigated in three selected locations in Oyo state using wind speed data that span between 12 and 20 years measured at 10 m height. In addition, the performance of selected small to medium size wind turbines in these sites were examined. The annual energy output and capacity factor for these turbines were determined. It was found that the monthly mean wind speeds in Oyo state ranges from 2.85 m/s to 5.20 m/s. While the monthly mean power density varies between 27.08 W/m2 and 164.48 W/m2, while the annual mean power density is in the range of 67.28 W/m2 and 106.60 W/m2. Based on annual energy output, wind turbines with cut-in wind speed of about 2.5 m/s and moderate rated wind speeds will be best suited for all the sites.

2011-01-01

451

Early Life History of the Nurseryfish, Kurtus gulliveri (Perciformes: Kurtidae), from Northern Australia  

Science.gov (United States)

... Brill, Leiden, The Netherlands. Berra, T. M. 2001. Freshwater fish distribution. Academic Press: San Diego, CA. Berra, T. M. ... ...

452

Dissemination of CTX-M-Type Extended-Spectrum ?-Lactamase Genes to Unusual Hosts  

UK PubMed Central (United Kingdom)

A Citrobacter amalonaticus and a Morganella morganii producing the CTX-M-1 extended-spectrum β-lactamase (ESBL) were isolated from an area where this enzyme...Full Text Available

2005-08-01

453

DTIC 8B9 2 14 0 5 1  

Science.gov (United States)

... TYPE F PFW NO IM M MW AERODYNAMICS TECHNICAL 01030 MEMORANDUM 397 t. CTO mSM F PDWW .U U. awma.ef MizE .

2011-05-05

454

Cytoplasmic heat shock granules are formed from precursor particles and are associated with a specific set of mRNAs.  

UK PubMed Central (United Kingdom)

In heat-shocked tomato cell cultures, cytoplasmic heat shock granules (HSGs) are tightly associated with a specific subset of mRNAs coding mainly for the untranslated control proteins. This messenger...Full Text Available

1989-03-01

455

Characterizing the spectral-temporal response of ... - MODIS Website  

Science.gov (United States)

... days after it burned, using a portable spectroradiometer (704 bands in the range 0.35 to 2.5 mu m) and an infrared thermometer (one band, 6 to 14 mu m). ...

456

Characterization of the 5'-terminal cap structures of early simian virus 40 mRNA.  

UK PubMed Central (United Kingdom)

Early simian virus 40-specific mRNA was isolated from lytically infected and stably transformed cells and analyzed with respect to the 5'-terminal cap content. An analogous diversity of capped structures...Full Text Available

1980-09-01

457

Characteristics of sugar uptake by immature maize embryos  

Energy Technology Data Exchange (ETDEWEB)

Characteristics of sugar uptake by immature maize embryos were determined in vitro utilizing a /sup 14/C-sugar solution incubation method. Hexose uptake rates were greater than those for sucrose, however, all showed biphasic kinetics. Glucose and fructose saturable components were evidence at <50 mM and sucrose at <5 mM. Chemical inhibitors (CCCP, DNP, NaCN, and PCMBS) and low temperature reduced sugar uptake. Sucrose influx was pH dependent while glucose was not. Embryos maintained a high sucrose to hexose ratio throughout development. At 25 days after pollination sucrose levels exceeded 200 mM while hexose levels remained below 5 mM. Glucose was rapidly converted to sucrose upon transport into the embryo. These circumstantial data indicate that sugar uptake by immature maize embryos is metabolically dependent and carrier mediated. Furthermore, sucrose transport appears to occur against its ...

1986-04-01

458

Calculations of long-lived isomer production in neutron reactions  

Energy Technology Data Exchange (ETDEWEB)

We have carried out theoretical calculations for the production of the long-lived isomers {sup 93m}Nb({1/2}{sup {minus}}, 16y), {sup 121m}Sn(11/2{minus}, 55 yr), {sup 166m}Ho(7-, 1200 yr), {sup 184m}Re(8+, 165 d), {sup 186m}Re(8+, 2{times}10{sup 5} yr), {sup 178m}Hf(16+, 31 yr), {sup 179m}Hf(25/2-, 25 d), {sup 192m}Ir(9+, 241 yr), all of which pose potential radiation activation problems in nuclear fusion reactors. We consider (n, 2n), (n,n{prime}), and (n, {gamma}) production modes and compare our results both with experimental data (where available) and systematic. We also investigate the dependence of the isomeric cross section ratio on incident neutron energy for the isomers under consideration. The statistical Hauser-Feshbach plus preequilibrium code GNASH was used for the calculations. Where discrete state ...

1991-01-01

459

CTX-M-Type Extended-Spectrum ?-Lactamases in Italy: Molecular Epidemiology of an Emerging Countrywide Problem  

UK PubMed Central (United Kingdom)

A nationwide survey of extended-spectrum β-lactamase (ESBL) production among Enterobacteriaceae, carried out in 2003, showed that CTX-M-type enzymes have achieved a sizeable...Full Text Available

2006-08-01

460

CTX-M ?-Lactamases in Escherichia coli from Community-acquired Urinary Tract Infections, Cambodia  

UK PubMed Central (United Kingdom)

Despite the recent global spread of CTX-M β-lactamases in Escherichia coli isolates from community-acquired urinary tract infections (CA-UTIs), their dissemination has been...Full Text Available

2009-05-01

461

APOD: January 25, 1997 - M51: The Whirlpool Galaxy  

Science.gov (United States)

on the picture will download the highest resolution version available. M51: The Whirlpool Galaxy Credit: W. Keel (U. Alabama), 1.1-meter Hall Telescope, Lowell Observatory...

2011-10-07

462

APOD: December 18, 1995 - M51: The Whirlpool Galaxy  

Science.gov (United States)

on the picture will download the highest resolution version available. M51: The Whirlpool Galaxy Credit: 1.1 Meter Hall Telescope, Lowell Observatory, Bill Keel (U. Alabama)...

2011-10-07

463

APOD: 2006 November 11 - M51: Cosmic Whirlpool  

Science.gov (United States)

on the picture will download the highest resolution version available. M51: Cosmic Whirlpool Credit: S. Beckwith (STScI) Hubble Heritage Team, (STScI/AURA), ESA, NASA...

2011-10-07

464

APOD: 2005 April 28 - M51: Cosmic Whirlpool  

Science.gov (United States)

on the picture will download the highest resolution version available. M51: Cosmic Whirlpool Credit: S. Beckwith (STScI) Hubble Heritage Team, (STScI/AURA), ESA, NASA...

2011-10-07

465

APOD: 2004 September 5 - M51: The Whirlpool Galaxy in Dust and...  

Science.gov (United States)

on the picture will download the highest resolution version available. M51: The Whirlpool Galaxy in Dust and Stars Credit: Credit: N. Scoville (Caltech), T. Rector (U....

2011-10-07

466

APOD: 2003 September 25 - Logarithmic Spirals Isabel and M51  

Science.gov (United States)

much in common. For starters, Isabel was hundreds of miles across, while M51 (the Whirlpool Galaxy) spans about 50,000 light-years making them vastly dissimilar in scale, not...

2011-10-07

467

APOD: 2002 July 11 - M51: X Rays from the Whirlpool  

Science.gov (United States)

picture will download the highest resolution version available. M51: X-Rays from the Whirlpool Credit: A. Wilson (UMD) et al., CXC, NASA Explanation: Fresh from yesterday's...

2011-10-07

468

APOD: 2001 April 10 - M51: The Whirlpool Galaxy in Dust and Stars  

Science.gov (United States)

on the picture will download the highest resolution version available. M51: The Whirlpool Galaxy in Dust and Stars Credit: N. Scoville (Caltech), T. Rector ( (NOAO) et al.,...

2011-10-07

469

A rapid and efficient method for region- and strand-specific mutagenesis of cloned DNA.  

UK PubMed Central (United Kingdom)

The single-stranded viral DNA of an M13 phage recombinant containing the early promoter region of SV40 was hybridized with linear, double-stranded replicative form DNA of a related M13 phage containing...Full Text Available

1982-01-01

470

1980-1990 - NASA Technical Report Server (NTRS)  

Science.gov (United States)

of the soleus in 6-mercaptopurine-treated rats. Experimental and Molecular Pathology. 43: 74-81, 1985. (GWU 5998). Jaweed, M.M.; Bozentka, D.; Hume, E.L.; ...

471

Final Scientific EFNUDAT Workshop  

ScienceCinema

...and it's really a pleasure to ...you and ...and for ...was shelled and then doses of pleasure for me to ...and my director general ...? and journal article ? ...but and yeah well that's um ? ...and ...and what could be achieved ? what might be the consequences ...? and ...and ...and ...and ...and ...structural because and ...over and hopefully is also serve the purpose to get ...principles and ...and ...and ...how to use them and future ...and and that ...and purposes and that's very important ...you and ...and ...and in the future ? and yeah ...true and ...and ...just and and and and and the order of nuclear physics a ...useful and ...too much ? and ...portable comes from and ...and ...and ...and ...no more ? how to knowledge and the and ...and ...and and keep ever seen all of all ? ...and ...and ...and what you're ...and ...and ...and you and ...and ...and ...and so when you keep that and and ...and ...? and ...and ...and ...the problems and the other side ? ...

472

Suppression of band crossing in the neutron-rich nuclei {sup 172,173}Yb due to the absence of a static pair field  

Energy Technology Data Exchange (ETDEWEB)

High-spin states in the neutron-rich nuclei {sup 172,173}Yb have been populated in a {sup 170}Er({sup 7}Li,(p,d,t)xn) incomplete-fusion reaction and the emitted {gamma}-radiation was detected with the GASP array. The signature partners of the 7/2{sup +}[633] rotational band of the odd-N {sup 173}Yb isotope have been newly established and were observed up to spin values of (45/2{sup +}) and (43/2{sup +}), respectively. The ground-state band of the even-even nucleus {sup 172}Yb has been observed up to a spin value of (22{sup +}). No band crossings were found in these bands. To explain this observation, it is proposed that the static pair field is absent, considering that the neutron odd-even mass differences reach for these nuclei very small values and that the band crossing is absent in cranked shell modell calculations without pairing. The results indicate, however, that strong dynamic correlations are still present. (orig.)

2005-10-01

473

Studies on sugar recognizing and binding protein (lectin) in marine invertebrates (physiological control of lectin); Kaiyo musekitsui dobutsu no toninshiki ketsugo tanpakushitsu (lectin) ni kansuru kenkyu (lectin no seiriteki seigyo)  

Energy Technology Data Exchange (ETDEWEB)

Lectin is a generic name of sugar binding protein in living organisms. With an objective to clarify physiological functions of lectin in marine invertebrates and utilize it as a useful material in the bio-chemical industry, studies were carried out on the chemical structure, distribution in living organisms and structural changes of lectin. Lectin is involved with such physiological actions as immunity reactions, generation and differentiation, Ca fixation and symbiosis. Lectin is one of the main components of lymph fluid in shellfish and crustacean, and is a multi-functional polymer that is related with foreign substance recognition, Ca transport, and shell formation. Lectin of a certain kind shows strong actions to accelerate cell division. Organs and cells were cultivated for lectin producing organs and lectin producing cells to verify the production thereof. Elucidation was attempted in a molecular level on such physiological functions as foreign substance ...

1993-03-01

474

Stability study of a gyrotron-traveling-wave amplifier based on a lossy dielectric-loaded mode-selective circuit  

Science.gov (United States)

The millimeter microwave source of gyrotron-traveling-wave amplifier (gyro-TWT) is capable of generating high power coherent radiation in a broad bandwidth, while its performance is severely deteriorated by the stability problems. This paper focuses on modeling and the stability analysis of the Naval Research Laboratory (NRL) Ka-band TE{sub 01} mode gyro-TWT based on an interaction circuit alternately loaded with lossy ceramic shells and metal rings. The propagation characteristics of the interaction circuit is analyzed first, based on which the boundary impedance method is employed to build an equivalent uniform lossy circuit. Then the stability of the interaction system is studied using linear and nonlinear theories. The analysis reveals that, due to the special waveguide structure and the dielectric loss, the propagation characteristics of the complex waveguide are similar to that of a uniform lossy circuit. The analysis of the absolute instabilities ...

2009-07-15

475

Stability study of a gyrotron-traveling-wave amplifier based on a lossy dielectric-loaded mode-selective circuit  

International Nuclear Information System (INIS)

The millimeter microwave source of gyrotron-traveling-wave amplifier (gyro-TWT) is capable of generating high power coherent radiation in a broad bandwidth, while its performance is severely deteriorated by the stability problems. This paper focuses on modeling and the stability analysis of the Naval Research Laboratory (NRL) Ka-band TE01 mode gyro-TWT based on an interaction circuit alternately loaded with lossy ceramic shells and metal rings. The propagation characteristics of the interaction circuit is analyzed first, based on which the boundary impedance method is employed to build an equivalent uniform lossy circuit. Then the stability of the interaction system is studied using linear and nonlinear theories. The analysis reveals that, due to the special waveguide structure and the dielectric loss, the propagation characteristics of the complex waveguide are similar to that of a uniform lossy circuit. The analysis of the absolute instabilities characterizes the ...

2009-07-01

476

On higher derivative corrections of tachyon action  

Energy Technology Data Exchange (ETDEWEB)

We have examined the momentum expansion of the disk level S-matrix element of two tachyons and two gauge fields to find, up to on-shell ambiguity, the couplings of these fields in the world volume theory of N coincident non-BPS D-branes to all order of {alpha}'. Using the proposal that the action of D-brane-anti-D-brane is given by the projection of the action of two non-BPS D-branes with (-1){sup F{sub L}}, we find the corresponding couplings in the world volume theory of the brane-anti-brane system. Using these infinite tower of couplings, we then calculate the massless pole of the scattering amplitude of one RR field, two tachyons and one gauge field in the brane-anti-brane theory. We find that the massless pole of the field theory amplitude is exactly equal to the massless pole of the disk level S-matrix element of one RR, two tachyons and one gauge field to all order of {alpha}'. We have also found the couplings of four tachyons to all order ...

2008-09-11

477

Numerical Simulation and Analyses of the Loss of Feedwater Transient at the Unit 4 of Kola NPP  

Science.gov (United States)

A three-dimensional numerical simulation of the loss-of-feed water transient at the horizontal steam generator of the Kola nuclear power plant is performed. Presented numerical results show transient change of integral steam generator parameters, such as steam generation rate, water mass inventory, outlet reactor coolant temperature, as well as detailed distribution of shell side thermal-hydraulic parameters: swell and collapsed levels, void fraction distributions, mass flux vectors, etc. Numerical results are compared with measurements at the Kola NPP. The agreement is satisfactory, while differences are close to or below the measurement uncertainties. Obtained numerical results are the first ones that give complete insight into the three-dimensional and transient horizontal steam generator thermal-hydraulics. Also, the presented results serve as benchmark tests for the assessment and further improvement of one-dimensional models of horizontal steam generator ...

2002-07-01

478

Nuclear mass prediction as an image reconstruction problem: can observed pattern determine mass values?  

Energy Technology Data Exchange (ETDEWEB)

Theoretical prediction of nuclear masses is analyzed as a pattern recognition problem on the N-Z plane. A global pattern is observed by plotting the differences between measured masses and Liquid Drop Model (LDM) predictions. After unfolding the data by removing the smooth LDM mass contributions, the remaining microscopic effects have proved difficult to model, although they display a striking pattern. These deviations carry information related to shell closures, nuc]ear deformation and the residual nuclear interactions. In the present work the more than 2000 known nuclear masses are studied as an array in the N-Z plane viewed through a mask, behind which the approximately 7000 unknown unstable nuclei that can exist between the proton and neutron drip lines are hidden. We show here that employing a Fourier transform deconvolution method these by masses can be predicted with similar accuracy than standard methods. We believe that a more general approach needs to be ...

2006-07-01

479

Nuclear mass prediction as an image reconstruction problem: can observed pattern determine mass values?  

International Nuclear Information System (INIS)

Theoretical prediction of nuclear masses is analyzed as a pattern recognition problem on the N-Z plane. A global pattern is observed by plotting the differences between measured masses and Liquid Drop Model (LDM) predictions. After unfolding the data by removing the smooth LDM mass contributions, the remaining microscopic effects have proved difficult to model, although they display a striking pattern. These deviations carry information related to shell closures, nuc]ear deformation and the residual nuclear interactions. In the present work the more than 2000 known nuclear masses are studied as an array in the N-Z plane viewed through a mask, behind which the approximately 7000 unknown unstable nuclei that can exist between the proton and neutron drip lines are hidden. We show here that employing a Fourier transform deconvolution method these by masses can be predicted with similar accuracy than standard methods. We believe that a more general approach needs to be ...

480

Magnetic nanoparticle detection using nano-SQUID sensors  

International Nuclear Information System (INIS)

We demonstrate detection of a single core-shell magnetite-silica nanoparticle (outer diameter #approx#120 nm, moment #approx#10"4#mu#_B) using an Nb dc superconducting quantum interference device (SQUID) with the loop size of 350 nm operational at T < 10 K. The system noise was minimized down to 0.2 #mu##PHI#_0 Hz"-"1"/"2 using a cryogenic SQUID series array pre-amplifier. Initial measurements of an individual magnetic nanoparticle were performed and a clear change of the noise spectra of the nano-SQUID was detected at low frequencies in the presence of the nanoparticle. Similar behaviour was confirmed with an FePt nanoparticle with a larger magnetic moment (diameter #approx#150 nm, moment #approx#10"6#mu#_B). Thus, we demonstrate a magnetic sensor based on a dc nano-SQUID and enabling detection of small moments (potentially down to a few electron spins). Such a sensor is of considerable significance for nanomagnetic metrology and quantum information processing ...

2010-12-01

481

Lifetimes of superdeformed nuclei in the mass region A {approx}150 with the Eurogam multidetector array; Durees de vie de noyaux superdeformes de la region de masse A {approx}150 mesurees avec le multicompteur Eurogam  

Energy Technology Data Exchange (ETDEWEB)

This work concerns the study of the nuclear superdeformation phenomenon in the rare earth region (A {approx} 150). The superdeformed (SD) states in Gadolinium and Dysprosium isotopes were produced via heavy-ion induced reactions and studied with the (EUROGAM EUROpean GAmma-ray Microscope) gamma multidetector array. Precise level attenuation method (DSAM). From the derived quadrupole moments, we find large differences in deformation between the yrast bands in neighbour nuclei explained in terms of the case of nuclei corresponding to an axis ratio of 2:1, the shell gaps are not fixed at a specific particle number and deformation. Furthermore the present results indicate that the deformations associated with identical bands are different supporting the picture that mass and deformation changes tend to compensate in SB bands with the same moments of inertia. (author). 114 refs.

1996-05-13

482

High resolution spectroscopy of second overtone transitions in solid parahydrogen  

Energy Technology Data Exchange (ETDEWEB)

The high resolution spectrum of the parahydrogen Q{sub 3}(0) transition at 11758 cm{sup -1} has allowed specific quantum state assignment of the ten lines which compose this transition. The transition cannot occur unless a dipole moment is induced in the parahydrogen by an external field. The quadrupole field of an impurity o-H{sub 2} molecule provides this field, and the transition occurs in the orientationally dependent field of the orthohydrogen molecule. Transitions induced by the quadrupolar field of the J=1 H{sub 2} in the nearest neighbor as well as in the next nearest neighbor shells have been observed. By lowering the impurity orthohydrogen concentration, the authors have observed lines with linewidths of approximately 15 MHz hwhm with a Ti:Sapphire laser having a sensitivity of 3x10{sup -5} ({Delta}I/I) using the toneburst method. Additionally, the second vibrational overtone of the impurity orthohydrogen molecule (Q{sub 3}(1)) has been observed at ...

1995-12-31

483

Hard X-ray identification of Eta Carinae and steadiness close to periastron  

CERN Document Server

Context: The colliding-wind binary Eta Car exhibits soft X-ray thermal emission that varies strongly around periastron, and non-thermal emission seen in hard X-rays and gamma-rays. Aims: To definitively identify Eta Car as the source of the hard X-ray emission, to examine how changes in the 2-10 keV band influence changes in the hard X-ray band, and to understand more clearly the mechanisms producing the non-thermal emission using new INTEGRAL observations obtained close to periastron. Methods: A Chandra observation encompassing the ISGRI error circle was analysed, and all other soft X-ray sources (including the outer shell of Eta Car itself) were discarded as likely counter-parts. New hard X-ray images of Eta Car were studied close to periastron, and compared to previous observations far from periastron. Results: The INTEGRAL component, when represented by a power law (with a photon index of 1.8), would produce more emission in the Chandra band than observed from ...

2010-01-01

484

Groundwater quality assessment plan for single-shell tank waste management Area U at the Hanford Site  

Energy Technology Data Exchange (ETDEWEB)

Waste Management Area U (WMA U) includes the U Tank Farm, is currently regulated under RCRA interim-status regulations, and is scheduled for closure probably post-2030. Groundwater monitoring has been under an evaluation program that compared general contaminant indicator parameters from downgradient wells to background values established from upgradient wells. One of the indicator parameters, specific conductance, exceeded its background value in one downgradient well triggering a change from detection monitoring to a groundwater quality assessment program. The objective of the first phase of this assessment program is to determine whether the increased concentrations of nitrate and chromium in groundwater are from WMA U or from an upgradient source. Based on the results of the first determination, if WMA U is not the source of contamination, then the site will revert to detection monitoring. If WMA U is the source, then a second part of the groundwater quality assessment plan will be ...

2000-03-21

485

GENERALIZED ATOMIC MASS LAW  

Science.gov (United States)

Least-squares analyses were performed on a set of atomic masses using standard and generalized senaiempirical mass laws. Presumably because of errors in the assured form of the standand mass law, its least-squares coefficients can be determined at best to an accuracy of about 10%, and masses are predicted with an uncertainty of several Mev/c/sup 2/. The standard mass law was generalized by addition of shell effect and deformation terms. While the least-squares fitting of the generalized mass law is better than for the standard mass law, it is still not possible to predict atomic masses to an accuracy better than a few Mev/c/sup 2/. The nuclear deformations and the well depth . of the nuclear interaction obtained from the additional mass-law terms are in reasonable agreement with more accurate determinations by other methods. A similar statement applies to the nuclear radius constant as obtained from the least-squares coefficient of ...

1959-11-15

486

Fluorescence quantum yields and cascade-free lifetimes of state selected CO_2"+, COS"+, CS_2"+ and N_2O"+ determined by photoelectron-photon coincidence spectroccopy  

International Nuclear Information System (INIS)

The details and principles of an apparatus built for measurements of fluorescence quantum yields and cascade-free lifetimes of open-shell cations are reported. These rely on the detection of coincidences between energy selected photo-electrons and undispersed photons. The results of such measurements for CO"+_2,COS"+,CS"+_2 and N_2O"+ in selected vibrational levels of their excited states are presented. Non-unity fluorescence quantum yields are found for some vibronic levels of CO"+_2(B), COS"+(A), N_2O"+(A) and a non-exponential decay is observed for CS"+_2(B). The data yield the following values for the radiative lifetimes: CO"+_2(A) 124 +- 6 ns,CO"+_2(B) 140 +- 7 ns, COS"+(A) 550 +- 50 ns and N_2O"+(A) 240 +- 12 ns. (orig.).

1980-10-01

487

Electric-field-induced deformation of biological cells  

Energy Technology Data Exchange (ETDEWEB)

The cell is modeled as an ellipsoid with shell and the surface stress distribution calculated by means of the Maxwell Stress Tensor. The cell membrane is treated as incompressible material having both bending and shear energies of deformation. Employing the principle of virtual work, cell volume (and hence shape) is computed as a function of the external field strength and orientation with respect to the field. The following results were obtained: (1) The surface stresses that develop or the cell membrane are distributed having both normal and tangential components that act together to produce a rounding of the cell. (2) If the tangential component of the stress is ignored, then higher field strengths are needed to produce similar deformation (shape change) of cells. (3) The threshold value of the applied field, i.e, the field strength at which the volume (shape) of the cell changes abruptly, occurs at approximately 55V/cm. Above the threshold value further ...

1989-01-01

488

Don't Panic! Closed String Tachyons in ALE Spacetimes  

Energy Technology Data Exchange (ETDEWEB)

We consider closed string tachyons localized at the fixed points of noncompact nonsupersymmetric orbifolds. We argue that tachyon condensation drives these orbifolds to flat space or supersymmetric ALE spaces. The decay proceeds via an expanding shell of dilaton gradients and curvature which interpolates between two regions of distinct angular geometry. The string coupling remains weak throughout. For small tachyon VEVs, evidence comes from quiver theories on D-branes probes, in which deformations by twisted couplings smoothly connect non-supersymmetric orbifolds to supersymmetric orbifolds of reduced order. For large tachyon VEVs, evidence comes from worldsheet RG flow and spacetime gravity. For C{sup 2}/Z{sub n}, we exhibit infinite sequences of transitions producing SUSY ALE spaces via twisted closed string condensation from non-supersymmetric ALE spaces. In a T-dual description this provides a mechanism for creating NS5-branes via closed string tachyon ...

2001-08-20

489

Development of a combined ultrasonic and eddy current inspection system for examination of the internal surfaces of water-filled austenitic piping  

Energy Technology Data Exchange (ETDEWEB)

After October 1993, Swedish BWR power plant operators will be required to present an inspection concept which will facilitate the nondestructive examination of recirculation system piping. According to the pertinent Swedish codes and standards, such inspections will be required to focus on internal pipe surfaces. Since it is impossible for external inspections to cover all essential areas with the necessary degree of sensitivity (geometry, beam attenuation), Siemens-KWU was commissioned to develop an inspection system which combines ultrasonic search units and eddy current probes to produce the required degree of examination sensitivity. A pipe crawler was developed to transport the inspection unit. This device can be used for the inspection of circumferential and longitudinal pipe welds, nozzle-to-pipe welds and RPV nozzle-to-shell welds. Special probes designed to fulfill inspection and manipulation requirements were developed for the inspection of the 30 welds ...

1994-12-31

490

Detections of SiO and H$_2$O Masers in the Bipolar Nebula IRAS 19312+1950  

CERN Document Server

We report on the detection of SiO and water masers toward a newly found bipolar nebula, IRAS 19312+1950. This object exhibits extreme red IRAS color log (F25/F12)=0.5 and log (F60/F25)=0.7 and a nebulosity having a size of about 30" extended to the South-West in the 2MASS near-infrared image. Toward this object, we have detected emission from the H2O 6(1,6)-5(2,3) transition, the SiO J=1-0, v=1 and 2, and J=2-1, v=1 transitions, and the SO 2(2)--1(1) and H13CN J=1-0 transitions. The thermal lines of SO and H13CN are shifted by about 12 km/s in radial velocity with respect to the maser lines, indicating that thermal emission comes from the background molecular cloud. However, the SiO J=2-1, v=2 spectrum shows another component of SiO emission separated by 26 km/s from the main component, that might be formed in a rotating or expanding shell.

2000-01-01

491

Concawe news brief: gasoline risk assessment at TCNES  

Energy Technology Data Exchange (ETDEWEB)

The risk assessment report for gasoline was discussed at the EU TCNES (Technical Committee for New and Existing Substances) on 1 December 2004. CONCA WE was represented at the meeting by Tom Parkerton (EMBSI), Peter Boogaard (Shell),Jan Urbanus (CONCA WE) and Duncan King (BP). First a short introduction to CONCAWE was given, followed by a summary of the on-going programme of risk assessments on groups of petroleum substances. The methodology and outline conclusions for the environmental and health risk assessment for gasoline were then presented. Member States were invited to comment on the draft risk assessment. It was clear that not ail of the Member States had yet reviewed the report in detail (it had been circulated to the Member States approximately 5 weeks in advance of the meeting). However, those that did provide comments (along with ail of all European Chemicals Bureau representatives) were ail very supportive of the CONCAWE initiative, recognizing the ...

2005-03-15

492

Bonding exterior grade structural panels with copolymer resins of biomass residue components, phenol, and formaldehyde  

Energy Technology Data Exchange (ETDEWEB)

Components of various forest and agricultural residue biomass-including the polyphenolic compounds-were converted into aqueous solution and/or suspension by extraction and digestion. Some biomass components reacted vigorously under alkaline catalysis with formaldehyde and initially showed a high degree of exothermic reaction; however, other components did not react as vigorously under these conditions, indicating that different biomass materials require different methods to obtain optimum reactivity for the copolymerization with phenol. Our primary goal is to develop adhesives capable of producing acceptable bond quality, as determined by the wood products industries` standards, under a reasonable range of gluing conditions. Copolymer resins of phenol, formaldehyde, and biomass components were synthesized and evaluated for gluability of bonding exterior grade structural replaced with chemicals derived from peanut hulls, pecan shell flour, pecan pith, southern pine ...

1993-12-31

493

Beta-decay studies of neutron-rich Sc-Cr nuclei  

International Nuclear Information System (INIS)

The neutron-rich nuclei"5"7","5"8_2_1Sc,"5"8"-"6"0_2_2Ti,"6"0"-"6"3_2_3V,"6"2"-"6"6_2_4Cr have been produced at Ganil via interactions of a 61.8A MeV "7"6Ge beam with a "5"8Ni target. Beta-decay studies have been performed using combined #beta#- and #gamma#-ray spectroscopy. Half-lives have been determined and #beta#-decay schemes are proposed for "5"8Ti, "6"1V and "6"2Cr. From these studies, new hints for the existence of #beta#-decaying isomers in "6"0V and in "6"2Mn are provided. These results are compared to shell model calculations. The role of the #pi#f_7_/_2- #nu#f_5_/_2 proton-neutron interaction is examined through its influence on the lifetime values. (orig.)

2005-01-01

494

Augmentation of laminar flow and heat transfer in flat tubes by means of helical screw-tape inserts  

Energy Technology Data Exchange (ETDEWEB)

The heat transfer a characteristics and friction factor in the horizontal double pipes of flat tubes with full length helical screw element of different twist ratio and helical screw inserts with different spacer length are investigated. Cold and hot water are used as working fluid in tube side and shell side respectively. The experiments covered a range of Reynolds numbers 5.7 x 10{sup 2} {<=} Re {<=} 1.31 x 10{sup 3}. The effect of spacer length on the heat transfer augmentation and friction factor and the effect of twist ratio on heat transfer augmentation and friction factor have been presented separately. The study shows that, the Nusslet number (Nu) and friction factor (f) decrease with the increase of S or Y for flat tube. The comparison between the data of present plain circular with that of previous plain circular tube showed a good agreement between them but the data of present plain flat tube showed a higher in heat transfer and pressure ...

2011-01-15

495

Apoferritin-Templated Yttrium Phosphate Nanoparticle Conjugates for Radioimmunotherapy of Cancers  

Energy Technology Data Exchange (ETDEWEB)

We report a templated-synthetic approach based on apoferritin to prepare radionuclide nanoparticle (NP) conjugates. Non-radioactive yttrium (89Y) was used as model target and surrogate for radioyttrium (90Y) to prepare the nanoparticle conjugate. The center cavity and multiple channel structure of apoferritin offer a fast and facile method to precipitate yttrium phosphate by diffusing yttrium and phosphate ions into the cavity of apofrritin, resulting a core-shell nanocomposite. The yttrium phosphate/apoferritin nanoparticle was functionalized with biotin for further application. The synthesized nanoparticle was characterized by transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy (XPS). We found that the resulting nanoparticles were uniform in size, with a diameter of around 8 nm. We tested the pre-targeting capability of the biotin-modified yttrium phosphate/apoferritin nanoparticle (yttrium phosphate/apoferritin nanoparticle) conjugate ...

2008-05-01

496

Advanced Coal Liquefaction Research and Development Facility, Wilsonville, Alabama. Run 261 with Illinois No. 6 Burning Star Mine coal  

Science.gov (United States)

This report presents the results of Run 261 performed at the Advanced Coal Liquefaction R & D Facility in Wilsonville, Alabama. The run started on January 12, 1991 and continued until May 31, 1991, operating in the Close-Coupled Integrated Two-Stage Liquefaction mode processing Illinois No. 6 seam bituminous coal (from Burning star No. 2 mine). In the first part of Run 261, a new bimodal catalyst, EXP-AO-60, was tested for its performance and attrition characteristics in the catalytic/catalytic mode of the CC-ITSL process. The main objective of this part of the run was to obtain good process performance in the low/high temperature mode of operation along with well-defined distillation product end boiling points. In the second part of Run 261, Criterion (Shell) 324 catalyst was tested. The objective of this test was to evaluate the operational stability and catalyst and process performance while processing the high ash Illinois No. 6 coal. Increasing viscosity ...

1992-09-01

497

Advanced Coal Liquefaction Research and Development Facility, Wilsonville, Alabama. Run 260 with Black Thunder Mine subbituminous coal: Technical progress report  

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of Run 260 performed at the Advanced Coal Liquefaction R&D Facility in Wilsonville. The run was started on July 17, 1990 and continued until November 14, 1990, operating in the Close-Coupled Integrated Two-Stage Liquefaction mode processing Black Thunder mine subbituminous coal (Wyodak-Anderson seam from Wyoming Powder River Basin). Both thermal/catalytic and catalytic/thermal tests were performed to determine the methods for reducing solids buildup in a subbituminous coal operation, and to improve product yields. A new, smaller interstage separator was tested to reduce solids buildup by increasing the slurry space velocity in the separator. In order to obtain improved coal and resid conversions (compared to Run 258) full-volume thermal reactor and 3/4-volume catalytic reactor were used. Shell 324 catalyst, 1/16 in. cylindrical extrudate, at a replacement rate of 3 lb/ton of MF coal was used in the catalytic stage. Iron oxide ...

1992-01-01

498

Advanced Coal Liquefaction Research and Development Facility, Wilsonville, Alabama  

Energy Technology Data Exchange (ETDEWEB)

This report presents the results of Run 260 performed at the Advanced Coal Liquefaction R D Facility in Wilsonville. The run was started on July 17, 1990 and continued until November 14, 1990, operating in the Close-Coupled Integrated Two-Stage Liquefaction mode processing Black Thunder mine subbituminous coal (Wyodak-Anderson seam from Wyoming Powder River Basin). Both thermal/catalytic and catalytic/thermal tests were performed to determine the methods for reducing solids buildup in a subbituminous coal operation, and to improve product yields. A new, smaller interstage separator was tested to reduce solids buildup by increasing the slurry space velocity in the separator. In order to obtain improved coal and resid conversions (compared to Run 258) full-volume thermal reactor and 3/4-volume catalytic reactor were used. Shell 324 catalyst, 1/16 in. cylindrical extrudate, at a replacement rate of 3 lb/ton of MF coal was used in the catalytic stage. Iron oxide was ...

1992-01-01

499

A hydrogen infrastructure - what, why, when and how - an oil industry perspective  

International Nuclear Information System (INIS)

Shell Oil's exploration of profitable business opportunities afforded by fuel cells and by the emergence of a viable hydrogen economy is discussed. The emphasis in this paper is on the transportation sector, particularly the importance of a refueling infrastructure and the influence that consumer attitudes will have on which technological solution will gain the upper hand in hydrogen-powered vehicle development. Key issues facing the oil industry with regard to development of hydrogen as the new energy carrier are also reviewed. Methanol reformer fuel cell cars are the most likely to gain acceptability in the short term, but the probability of methanol fuel cell vehicles being replaced by gasoline or hydrogen fuelled fuel cell vehicles or be superseded by advances in internal combustion engine and after-treatment technology, are very real. Government regulations, fiscal incentives and societal pressures will be the principal determinants of development. Beyond ...

1999-02-07