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1.
A. Bagheri K. L. Baluja Savita M. Datta 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1994,32(3):211-217
The density (N) dependence of electron mobility (μ) in various dense gases (H2, N2, O2, CO2 and rare gases) has been calculated using a multiple-scattering approach. Deviation of the high density gas from its perfect gas behaviour has been taken into account through the temperature-dependent second virial coefficient. Multiple scattering of electrons leads to shifts in their kinetic energy and it also changes their distribution functions. This unified approach predicts both positive and negative effects. The positive (negative) effect entails on increase (decrease) of μ withN. We have assessed the available data on momentum transfer cross-sections by comparing the mobility at very low densities (Nμ)0 with experimental results. The density dependence is studied by comparing the calculated ratioNμ)/Nμ)0 with the observed values and other theoretical work. The Legler model which assumes a constant cross-section is inadequate for predicting the observed density dependence. We obtain good agreement with available experimental work for all the atomic and molecular species studied here. 相似文献
2.
The oscillator strengthsf forE1 transitions along an isoelectronic sequence can be written asf=aK
2+bK+c whereK is a gauge parameter representing the gauge condition of the electromagnetic field. The coefficientsa,b, andc are functions of length (f
l) and velocity (f
v) values of the oscillator strengths at the Hartree-Fock level. We have shown by making a perturbation expansion of oscillator strengthsf,f
l andf
v that the gauge parameterK is independent of the nuclear charge. This property has been exploited to extrapolatef values along the isoelectronic sequence of Boron for some representativeE1 transitions within then=2 complex. We obtain good agreement between the extrapolated results with the configuration interaction results. 相似文献
3.
Moriya K. Yamada T. Sakai K. Yano S. Baluja S. Matsuo T. Pritz I. Vysochanskii Y. M. 《Journal of Thermal Analysis and Calorimetry》2002,70(2):321-328
Heat capacities of the Pb2xSn2(1-x)P2Se6 crystals (x=0, 0.098, 0.251, 0.402 and 1.0) were measured using an adiabatic calorimeter at temperatures between 10 and 350 K. In the
crystal of x=0, two heat capacity anomalies corresponding to the ferroelectric commensurate - intermediate incommensurate(C-IC) phase
transition temperature T
i, and the incommensurate - paraelectric (IC-N) phase transition temperature T
c, were observed at 193.24±0.10 and 220.07±0.15 K, respectively. The phase transition temperatures decreased with an increase
in Pb2+ concentration. The anomaly at Ti disappeared at x=0.251 in the mixed systems of the Pb2xSn2(1-x)P2Se6. In the crystal of Pb2P2Se6 (x=1.0), no phase transition was observed. The normal heat capacities for the mixed crystals were determined by least squares
fitting of the Debye and Einstein functions to the experimental data. The anomalous heat capacities gave the phase transition
entropies of 8.5 and 1.5 J mol-1 K-1 for x=0. The large transition entropies are consistent with an order-disorder mechanism in the ferroelectric-paraelectric phase
transitions in x=0.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
K. L. Baluja Anju Gupta Savita M. Datta 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,28(2):105-108
Configuration interaction wavefunctions, transition energies, line strengths and transition probabilities for allowed transitions within then=2 complex of C-like Fe XXI have been calculated in the LS coupling scheme. We included internal, semi-internal, and all-external types of correlations. We compare our non-relativistic line strengths values with those of relativistic calculations in the Breit-Pauli approximation. The relativistic effects on line strengths are negligible for all transitions except for the transition1 D e →1 D 0. Experimental wavelengths are used in the calculation of transition probabilities. 相似文献
5.
Miss S. Baluja R. N. Singh R. Tripathi B. M. Shukla 《Journal of Radioanalytical and Nuclear Chemistry》1985,94(4):233-239
Tracer diffusion of131I– ions is studied at different temperatures /20°C–50°C/ in 2.5% agar gel containing sodium and potassium sulphate solutions over a wide range of concentrations. The results are in qualitative agreement with the theoretical values in the concentration range 10–6–10–1M. Agar gel shows an obstruction effect to diffusional flow. The activation energy for tracer diffusion was found to be of the order of 16.3 kJ mol–1. 相似文献
6.
M. Gupta K. L. Baluja 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(3):475-483
Electron-H2S collision process is studied using the R-matrix method. Nine low-lying states of H2S molecule are considered in the R-matrix formalism to obtain elastic integral, differential, momentum transfer and excitation cross sections for this scattering
system. We have represented our target states using configuration interaction (CI) wavefunctions. We obtained adequate representation
of vertical spectrum of the target states included in the scattering calculations. The cross sections are compared with the
experiment and other theoretical results. We have obtained good agreement for elastic and momentum transfer cross sections
with experiment for entire energy range considered. The differential cross sections are in excellent agreement with experiment
in the range 3–15 eV. A prominent feature of this calculation is the detection of a shape resonance in 2B2 symmetry which decays via dissociative electron attachment (DEA). Born correction is applied for the elastic and dipole allowed
transition to account for higher partial waves excluded in the R-matrix calculation. The electron energy range is 0.025–15 eV. 相似文献
7.
R. Gajera R. Bhalodia S. Baluja 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2010,84(5):766-770
Sound velocities of solutions of some derivatives of dihydropyrimidines (DHPMs) in N,N-dimethylforamide (DMF) and dimethyl
sulfoxide (DMSO) were measured at 298.15 K over a wide range of concentration. Adiabatic compressibilities, apparent adiabatic
molar compressibilities and apparent adiabatic molar volumes were also evaluated. Results of sound velocity measurements provide
useful information about ion-ion and ion-solvent interactions and are of significant help in understanding the behavior of
electrolytes in solutions. 相似文献
8.
Many molecules with an even number of electrons belong to open-shell systems due to π
2 ground state electronic configuration. This configuration gives rise to three low-lying states X
3
Σ
−, a
Δ
1 and b
1
Σ
+. The inclusion of these target states in a trial wave function of the entire scattering system have important implications
in the resonances that may be detected in these open-shell molecules. Various molecules like O2, PX (X = H and halogens), SO, Si2, BF have π
2 ground state configuration. The R-matrix method is a well established ab initio formalism to calculate differential, integral and momentum-transfer cross sections for the elastic scattering of electrons
by molecules. We have calculated these cross sections for PH and SO molecules in the incident electron energy range 0–10 eV.
The results are obtained by using the R-matrix method in which the closecoupling expansion of the wave function of the scattering system includes only the ground
state. This target state is described by configuration interaction wave function that includes correlation effects. The cross
section for electron impact on PH and SO are presented. 相似文献
9.
Alla Zablotskaya Izolda Segal Yuris Popelis Edmunds Lukevics Shipra Baluja Irina Shestakova Ilona Domracheva 《应用有机金属化学》2006,20(11):721-728
A series of triorganylsilyl(β‐dialkylaminoethoxy)silanes was prepared and characterized by elemental analysis, 1H, 13C, 29Si NMR and mass spectroscopy. Comparative study of 29Si resonance of newly synthesized compounds showed correlation between its value and substituent nature at the silicon atom, and is shifted upfield for β‐triorganyl(N,N‐dialkylaminoethoxy)silanes in comparison with corresponding methiodides, revealing weak N…Si interaction for proper silanes. In vitro antitumour and antimicrobial properties were investigated. The biological activity data exhibited a marked enhancement of inhibitory activity on trialkylsilylation against tumour cell lines and all the test bacterial/fungal strains. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
10.
Variousworkershavereportedthepreparation,chemicalandphysicalpropertiesofvariousSchiffbases犤1-5犦.Schiffbasesareknowntobeimportantduetotheirapplicationsintheprepa-rationofdyes,liquidcrystalsandpowerfulcorrosionin-hibitors.Furthermore,theyareusedinthemecha… 相似文献