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91.
The effects of SO
4
2–
doping and Y-irradiation on the isothermal (563 K) decomposition of barium bromate have been investigated gasometrically with a vacuum apparatus. Plots of the fraction decomposed avs. timet for pure, doped and irradiated crystals exhibited characteristic stages: initial gas evolution (initial puff), an induction period, linear reaction, an acceleratory period and decay. The data are considered in the light of various kinetic models, e.g. linear rate equation, Prout-Tompkins and Avrami-Erofeev. The plausible mechanism of the reaction and the effects on this of anion vacancies and Y-irradiation are discussed briefly.
The authors thank the Department of Atomic Energy, Government of India, for financial support. M.K.S. also gratefully acknowledges the award of a Research Fellowship by the same agency, which made the work possible. 相似文献
Zusammenfassung Die Wirkung von Versetzen mit SO 4 2} - und -Bestrahlung auf die isotherme (563 K) Zersetzung von Bariumbromat wurde gasometrisch untersucht. Es zeigte sich, daß die Zeitcharakteristiken für die reinen, die versetzten und bestrahlten Kristalle verschiedene Stufen durchlaufen, nämlich anfängliche Gasentwicklung (Aufblähen), Induktionsperiode, lineare Reaktion, Beschleunigung und Abklingen. Die Daten wurden unter dem Gesichtspunkt verschiedener kinetischer Modelle betrachtet, z. B. lineare Geschwindigkeitsgleichung, das Modell von Prout-Tompkins und Avrami-Erofeev. Es werden kurz ein einleuchtender Reaktionsmechanismus und der Einfluß von Anionengitterlücken und -Bestrahlung darauf diskutiert.
- (563 ) . , ,-, «t» , , , , , . , - -. .
The authors thank the Department of Atomic Energy, Government of India, for financial support. M.K.S. also gratefully acknowledges the award of a Research Fellowship by the same agency, which made the work possible. 相似文献
92.
Time-resolved ground-state spectroscopy is able to follow triplet kinetics by probing the time course of ground-state recovery by bleacing and probing with light of identical wavelength. From the maximum of transient absorption and its long-lived plateau due to triplet population the triplet yield can be determined without using triplet—triplet absorption. A repetitive picosecond spectrometer is used to measure triplet yields of a xanthene dye with different heavy-atom substituents. 相似文献
93.
Subas Chandra Jena Rashmi Mishra Sakuntala Swain 《Proceedings Mathematical Sciences》1993,103(2):135-140
This paper reports a result for proving a triangular matrix summability of a factored Fourier series by extending the theorem on Nörlund summability of a factored Fourier series att =x when ?(t)∈B.V in (0, π) due to Singh [4] (Indian J. Math. 9 227–236). The result generalizes the theorem of Varshney [5] (Proc. Am. Math. Soc. 10, 784–789) and that of Singh. 相似文献
94.
95.
96.
97.
98.
Ba2Zn2Fe12O22 was synthesized by solid state reaction technique. The temperature and frequency dependent electrical properties and complex impedance spectroscopy were analysed. Complex modulus formalism shows the existence of high resistance and small capacitance of the material for the short range relaxation. The presence of non-Debye type relaxation is revealed from Nyquist plots and enabled to separate the contribution from bulk and grain boundary effect in the material. Further, the ac electrical conductivity of the material was well agreed with the Jonscher's universal power law. 相似文献
99.
100.
R. Venkata Krishnan Hrudananda Jena K. V. Govindan Kutty K. Nagarajan 《Journal of Thermal Analysis and Calorimetry》2010,101(1):371-377
Rare earth uranates Nd6UO12, Gd6UO12 and Eu6UO12 were prepared by combustion synthesis and characterized by XRD. Single-phase rhombohedral structure was observed for all
the above compounds. Heat capacity measurements were carried out on Nd6UO12 and Gd6UO12 with differential scanning calorimetry in the temperature range 298–800 K. Enthalpy, entropy and Gibbs energy functions were
computed. Heat capacity values of Nd6UO12 and Gd6UO12 at 298 K are 436 and 400 J K−1 mol−1, respectively. Thermal expansion characteristics were studied using high temperature X-ray diffraction (HTXRD) in the temperature
range 298–873 K. The coefficients of thermal expansion measured for Eu6UO12 are 10.5 × 10−6 and 7.3 × 10−6 K−1 along a- and c-axis, respectively. Similarly, the coefficients of thermal expansion of Gd6UO12 along a-axis are 10.0 × 10−6 K−1 and along c-axis is 9.7 × 10−6 K−1. 相似文献