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A. M. George N. C. Mishra M. S. Nagar N. C. Jayadevan 《Journal of Thermal Analysis and Calorimetry》1996,47(6):1701-1708
Thermal decomposition of the amorphous coprecipitate of yttrium and aluminium hydroxides forming yttrium aluminium garnet has been investigated employing thermal analyses, X-ray diffraction and IR spectroscopy. On heating, the coprecipitate progressively loses water forming a stable but highly disordered hydroxy garnet which crystallizes at 1180 K and decomposes to YAG at 1290 K. Nucleation of the crystalline phase appears to begin at 800 K.The authors thank Dr. P. V. Ravindran of the Analytical Chemistry and Shri N. K. Kulkarni of the Fuel Chemistry Divisions of BARC for their assistance in the thermoanalytical experiments. 相似文献
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Sanghamitra Khatua S. N. Mishra S. H. Devare H. G. Devare 《Hyperfine Interactions》1993,78(1-4):547-552
The local susceptibilities (T) of isolated Rh impurities in paramagnetic dilute Pt(Fe) alloys have been measured using the TDPAC method. The results show existence of 4d magnetic moment for Rh with reduced spin fluctuation temperatures (T
sf). It is suggested that moment stability scaled byT
sf is governed mainly by the interatomic d-d exchange interaction caused by induced ferromagnetic polarization of host d band electrons. 相似文献
49.
V. V. Krishnamurthy S. N. Mishra Ravi Kumar S. H. Devare H. G. Devare 《Hyperfine Interactions》1993,78(1-4):541-545
Local magnetic behaviour of Rh implanted into Ni-Rh alloys near the critical Rh compositionx=0.37 has been studied using the TDPAC method. The observed Curie-Weiss type local susceptibility reflects the presence of large d spin polarization around Rh yielding a total moment of 4.7 B. Our results show that the magnetism of Rh in the alloys depends strongly on the number of Ni near neighbour atoms. 相似文献
50.
Rapid dissolution procedure for base-metals-bearing complex materials for quality control assessment
A less labour-intensive method, involving a mixture of 1.0 g MnO2 + 20 mL HCl (11), is proposed for decomposing seven ores and six metallurgical products for accurate and precise estimation of copper, lead, zinc, cobalt and nickel for quality control assessment. Twentyone international reference materials were also analysed. Results of regression analyses are presented and intermethod comparison studies reveal that the probability of results being different compared with a reference method was less than 1%. Sample decomposition is straightforward and the method has been found to be very simple, rapid and easily adaptable, as it involves no separation of the analyte from the matrix elements. 相似文献