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131.
132.
Electrical resistivity of Ag:0.29 at % Au alloy has been measured and explained theoretically with the aim of understanding the deviations from Matthiessen's rule. The anisotropy in the electron-phonon interaction, the recoil of the impurity, mass-changes, nearest neighbour radial and angular force-constant-changes and Debye-Waller factors have been taken into consideration. 相似文献
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135.
The (4, 4*) ⊕ (4*, 4) model of broken chiral SU (4) × SU (4) symmetry has been used to calculate the third-order coupling
constants involving charmed and ordinary pseudoscalar mesons. These coupling constants are exploited to derive some interesting
new relations among the masses and decay constants of these charmed particles. Using the known masses and decay constants
as inputs, we exploit these relations to predict:F
D = −1·41F
π
,F
F = −1·13F
π
,F
D/FF = 1·25,m(D
s) = 1·43 GeV,m(F
s) = 1·39 GeV andm(K
s) = 1·02 GeV. 相似文献
136.
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138.
Thermoluminescence (TL) and electron spin resonance studies have been carried out on SrS:Bi phosphor. The TL glow curve is broad and indicates a dominant peak at 120 °C with two additional peaks, not clearly resolved, appearing as shoulders at around 180 and 250 °C. Two defect centres are observed at room temperature. One of them is characterized by an isotropic g-value 2.0034 and is assigned to an F+ centre. Step annealing measurements indicate a possible association between the F+ centre and the three TL peaks. 相似文献
139.
Nonlinear Dynamics - We consider the theoretical maximum extractable average power from an energy harvesting device attached to a vibrating table which provides a unidirectional displacement... 相似文献
140.
J. S. Shukla R. K. Tiwari 《Journal of polymer science. Part A, Polymer chemistry》1981,19(6):1517-1524
The aqueous polymerization of methacrylamide (I) initiated by KBrO3–thioglycolic acid (TGA) has been studied at 30 ± 0.2°C in nitrogen. The rate is given by K[M]1.19 [thioglycolic acid]1 [KBrO3]0.53 for 10–15% conversion. Activation energy was found to be 53.96 kJ/mole (12.92 kcal/mole) in the investigated range of temperature 30–45°C. The role of addition of a series of aliphatic alcohols and some salts was also determined. The kinetics of polymerization was followed iodometrically. 相似文献