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171.
S.K. Malik R. Vijayaraghavan S.K. Garg R.J. Ripmeester 《Solid State Communications》1977,21(3):245-247
The 119Sn Knight shift in SmSn3 has been measured in the temperature range 15—300 K, and it is found that the 4f-contribution to the Knight shift does not show a sign reversal in this temperature interval. The range of crystal field parameters for which simultaneous fit to the magnetic susceptibility and the extended Knight shift results in SmSn3 is obtained can be substantially narrowed from that reported earlier. 相似文献
172.
The finite amplitude longitudinal waves along a uniform bar are examined by using the method or multiple scales. The evolution of the complex amplitude of a quasi-monochromatic progressive wave is shown to be governed by a non-linear Schrödinger equation. The analysis reveals that the constant amplitude progressive waves are stable against modulation. 相似文献
173.
174.
ITO–SiOx–nSi semiconductor–insulator–semiconductor (SIS) structures have been produced with a simple spraying technique. It is shown that the structures obtained in such a way may be considered as an induced p–n diode, in which the polycrystalline tin–doped indium oxide (ITO) layer spray deposited on the preliminary treated silicon surface leads to an inversion p-layer at the interface. Solar cells with an active area of 1–4 cm2 have been fabricated based on ITO–SiOx–nSi structures and studied. Under AM0 illumination conditions, the efficiency is nearly 11%, whereas it exceeds 12% for AM1.5 illumination conditions. The theoretical analysis provided in this work shows a good agreement with experimental results and allows for predicting the efficiency of the cells depending on the silicon electro-physical properties. 相似文献
175.
D. T. Adroja R. Nagarajan S. K. Malik B. D. Padalia R. Vijayaraghavan 《Hyperfine Interactions》1988,41(1):535-538
New ternary compounds having the formula EuTCu4 where T=Al, Pd and Ag have been synthesized. All these compounds are found to crystallize in the hexagonal CaCu5 type structure. Magnetization measurements reveal that these compounds are magnetically ordered with magnetic moments close to 7 μB. The Curie temperatures obtained from low field ac susceptibility measurements are 26K, 25K and 50K for T-Al, Pd and Ag respectively.151Eu Mössbauer studies at room temperature show a large negative isomer shift relative to SmF3. A hyperfine split pattern is observed at 4.2K in all these compounds, indicating that Eu ion is present in a divalent state and is magnetically ordered. 相似文献
176.
The oxide system Bi2.2Ca2.8−x
Sr
x
Cu2O
y
has been investigated for superconductivity as a function of Ca/Sr ratio withx=0.7, 1.0, 1.4 and 1.8. All these compositions are found to be superconducting with onset temperature in the range of 80–90
K implying a large homogeneity range between Sr and Ca for the superconductivity to occur in this system. Effect of partial
replacement of Bi by rare earths has been studied and it is observed that 20% replacement of Bi by Nd and Eu does not significantly
affect the superconducting transition temperature. 相似文献
177.
178.
In the reactions of meta- and para-alkyl substituted benzoic acids with aryl Grignard reagents, in tetrahydrofuran solutions and in the presence of nickel salts, the ESR spectra of the anion radicals of carboxylates derived from the benzoic acids were observed which represent the intermediates in the formation of ketyl radicals. 相似文献
179.
Summary The magnetic susceptibilities of certain vanadium pentoxide systems supported by kieselgur have been determined in the temperature
interval 30° to 400° C. The plot of reciprocal susceptibility against temperature for all the systems studied indicates sudden
deflections at temperatures which are about 150° lower than those of optimum catalytic activity. It has been suggested that
these points may mark the temperatures of commencement of structural changes which may be responsible for the activity of
these catalysts.
Zusammenfassung Die magnetische Susceptibilit?t gewisser Vanadium-Pentoxyd-Systeme mit Kieselgur als Tr?ger wurden im Temperaturintervall zwischen 30 und 400° C bestimmt. Die Auftragung der reziproken Susceptibilit?t gegen die Temperatur zeigt für alle untersuchten Systeme pl?tzliche Knicke bei Temperaturen, die etwa 150° niedriger liegen als die optimale katalytische Aktivit?t. Es wird vermutet, da? diese Knickpunkte die Temperaturen des Beginns von Struktur?nderungen zeigen, die für die Aktivit?t dieser Katalysatoren verantwortlich sind.相似文献
180.