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101.
We provide experimental evidence for stretching and collapse of neutral polymer layers, already adsorbed at an oil-in-water interface, due to its interaction with surfactants. Upon stretching, the first interaction length (2L(0)) follows a power law dependence on surfactant concentration ( proportional, variant C(x)(s), where x approximately 0.5 for cationic surfactants) and collapses in the presence of salt, as a relatively weak power law (C(-y)(s), where y=0.17), in good agreement with brush length decay for polyelectrolyte brushes. 相似文献
102.
The electronic structure of substitutional non-magnetic impurities Cu, Ag, Cd, Mg, Zn, Ga, In, Ge, Si and Sn in Al is studied
using density functional theory. A simple physical model is proposed to calculate the effective charges on impurities in trivalent
metal Al. A linear relation is found between the effective charges on impurities and impurity vacancy capture radii. The spherical
solid model (SSM) is used to account for discrete nature of the host. The impurity-induced change in charge density, scattering
phase shifts, host-impurity potential, residual resistivity and impurity self-energy are calculated. Higher order scattering
phase shifts are found significant and the host-impurity potential is found proportional to effective charge on impurity in
its vicinity. The self-consistently calculated potential is used to calculate the electric field gradients (EFGs) at the first
and second nearest neighbours (1NNs, 2NNs) of impurity. The calculated values are in agreement with the experimental results. 相似文献
103.
V. K. Gupta S. K. Badval I. K. Daftari G. L. Kaul L. K. Mangotra N. K. Rao S. K. Sharma Gian Singh Y. Prakash 《Zeitschrift fur Physik C Particles and Fields》1981,10(1):29-36
The shower particle multiplicity (〈n s 〉) in thep-nucleus interactions for different targets, in the incident energy range of ~6–500 GeV has been studied. The variation of multiplicity parameters with target mass (A) or with number of interactions that the incident hadron suffers inside the nucleus (v A ) and with the changed particle multiplicity inp-p interactions (〈n ch〉) has been examined in the light of the various models of multiparticle production. The present analysis favours the hydrodynamical model though some other models can not be conclusively ruled out. 相似文献
104.
S. Prakash 《Fresenius' Journal of Analytical Chemistry》1962,192(3):425
Ohne Zusammenfassung 相似文献
105.
Kalyan Kali Sengupta Biswanath Basu Shipra Sengupta Sanghamitra Nandi 《Polyhedron》1983,2(10):983-986
Hypophosphite ion is oxidised by Au(III) in aqueous hydrochloric acid to give phosphorus acid and Au(I). The kinetics of the reaction has been studied spectrophotometrically in the UV region at different temperatures. The oxidation of hypophosphorous acid is first order with respect to both Au(III) and substrate. Hydrogen ion has no effect on the rate in acid media (0.15–1.0)M. The energy and entropy of activations are 128 ± 3.0kJ mol?1 and 135.8 ± 6.5 JK?1 mol?1 respectively. The results are interpreted in terms of the probable formation of intermediate Au(lI). 相似文献
106.
Steady propagation of a single pulse in an inhomogeneously broadened resonant medium is studied. 2π-pulse solutions which are slightly different from those given in the literature are reported and it is shown that π-pulse solutions do not exist. 相似文献
107.
108.
B.G. Prakash 《Journal of sound and vibration》1980,70(2):303-305
109.
S. S. Rattan A. V. R. Reddy V. S. Mallapurkar R. J. Singh Satya Prakash 《Journal of Radioanalytical and Nuclear Chemistry》1981,67(1):95-99
A simple method is reported in this paper to estimate229Th in the presence of228Th. The total activity of229Th and228Th was determined by following the alpha activity growth (using a liquid scintillation counter and proportional counter) of
purified thorium samples. The activity ratio of229Th/228Th was determined by alpha spectrometry. From the initial total activity and ratio, disintegration rates of229Th and228Th were calculated. The values obtained for the activities have a precision better than ±2%. 相似文献
110.