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171.
172.
R. Singh R. M. Misra D. C. Gupta D. D. Shukla M. N. Sharma M. P. Madan 《Zeitschrift für Physik B Condensed Matter》1985,58(2):83-89
The parameterC
1=[(1/K
T
)/P]
T
, which describes the pressure variation of the compressibility, has been examined correlating the thermodynamical and interatomic potential approaches employing fewer approximations than has been usual heretofore. General expressions have been derived forC
1 by including the thermal correction terms, which have generally been ignored in previous studies concerning thermal properties of ionic crystals. The parameterC
1 has also been related to the Grüneisen parameter, , using a relation given earlier. The applicability of the derived equations is investigated and discussed for alkali halides employing few realistic potential forms. A good general accord is found with the available experimental data, which exhibits an essential improvement over other theoretical determinations. 相似文献
173.
Using the Wigner-Kirkwood expansion and bare Lennard-Jones (LJ) (12-6) potential, an effectiveLJ potential is derived, which includes the quantum effects through the expressions of the effective diameter∂(T, λ) and well-depth
(T, λ). We use theWCA perturbation theory to calculate the free energy and pressure for theLJ and effectiveLJ potentials. Simple analytic expressions are given for the reference system and the first order correction calculated. The
results are quite good at high density. The quantum effects on the free energy and pressure are also discussed. 相似文献
174.
175.
K. Nagarajan M. Bhupathy Rajendra Prasad Ziley Singh V. Venugopal D.D. Sood 《Thermochimica Acta》1980,36(1):85-89
The thermal decomposition kinetics of Pr2(SO4)3 to Pr2O2SO4 have been studied by isothermal weight change determination. The reaction was found to obey a linear law up to α = 0.5; beyond α = 0.5 it could be described as a phase-boundary controlled process. A dependence of the activation energy upon the sample weight was observed. The changes in surface area and density which occur during the decomposition are also given. 相似文献
176.
Summary A series of square planar complexes of the type [PdX2L2] where X=Cl, Br, I; L=telluracyclopentane (tcp), telluracyclohexane (tch) or benzotelluracyclopentane (btp) have been synthesised. The complexes were characterised by far-i.r., n.m.r. and u.v.-vis. spectroscopy. The data implytrans-geometries except for the complex [PdCl2(tch)2] where a mixture ofcis- andtrans-isomers is obtained. 相似文献
177.
A study of the fragmentation of l-methyl-3-(2-benzothiazolylhydrazono)-2-indolinones on electron impact reveals that the major processes involve N? N bond fission and the competing loss of CO from the molecular ion. 相似文献
178.
Bhagwan S. Garg Ranjana Dixit Asha L. Singh 《Journal of Thermal Analysis and Calorimetry》1990,36(7-8):2567-2582
Three different types of iron(III) complexes, Fe(A)3, Fe(A)2(A') and Fe(A)(A')2, whereA is either piperidyldithiocarbamate or morpholyl dithiocarbamate andA' is glycine(oxine) acetylacetone have been prepared by reacting Fe(III) salt with sodium salt of piperidinedithiocarbamic acid or morpholine-dithiocarbamic acid and acetylacetone(oxine)-glycine in different ratios. The mixed ligand complexes have been characterised by elemental analysis, magnetic susceptibility measurements, infrared, electronic spectral techniques and by thermal analysis. Electronic spectral studies suggests that all the complexes possess distorted octahedral geometry. The magnetic moment of the high spin iron(III) complexes lies in the range of 5.88–6.00 and for low spin lies in the range of 3.36–4.34 B.M. TG studies show one step decomposition of complexes and formation of Fe2O3 at the end of the step. 相似文献
179.
The technique of three-phase partitioning (TPP) was used to purify the green fluorescent protein (GFP) in a single step. TPP uses a combination of ammonium sulphate and tert-butanol to precipitate proteins from their crude extracts. In the first round of TPP with 20% ammonium sulphate saturation at the ratio of crude to tert-butanol 1:1 (v/v), most of the GFP remains in the lower aqueous phase. When subjected to a second round of TPP with 60% ammonium sulphate saturation at the ratio of crude to tert-butanol 1:2 (v/v) gives 78% recovery of GFP with a 20-fold purification. The sodium dodecyl sulphate-polyacrylamide gel electrophoretic (SDS-PAGE) analysis of purified preparation shows single band. The fluorescence excitation and emission spectra agreed with values reported in literature. 相似文献
180.