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771.
Single crystals of triammonium citrate are grown from aqueous solution and characterized using X-ray and etching studies. Using single crystal X-ray diffraction, the crystal is found to be orthorhombic with lattice parametersa = 6·223 Å,b = 15·048 Å andc = 11·056 Å. Surface studies on the as-grown faces reveal stratigraphic patterns. Of the several etchants tried, glacial acetic acid appears to be the best etchant for revealing dislocation sites on the as-grown faces. 相似文献
772.
Y. K. Rao 《Metallurgical and Materials Transactions A》1987,18(3):327-333
Although the Gibbs phase rule remains one of the cornerstones of thermodynamics, its usefulness has been severely limited
by a lack of suitable framework to find the number of independent components in a system. This paper rectifies this shortcoming.
It offers a comprehensive method, with suitable examples, to enable the determination of the minimum number of independent
composition-parameters, which are to be understood as ‘components’ in the Gibbsian sense. The method offered here is particularly
useful for complex systems composed of several elements and many phases. The present work also helps dispel much of the confusion
that had beset the concept of independent components since the early days of Gibbs. 相似文献
773.
774.
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776.
Hyeong Lee Chong Un 《Communications, IEEE Transactions on》1985,33(8):809-819
In this paper the performances of four statistical voice/data multiplexers are analyzed and compared. The structures of these multiplexers are based on the newly proposed queueing, frame management, and integrated flow control methods. For the queueing purpose, two separate finite voice and data buffers are used to queue voice and data packets independently. For frame management, four versions of master frame management are considered. As for the integrated flow control algorithm, speech coding techniques such as variable rate coding and embedded coding are considered. To evaluate the performances of the multiplexers, analytical formulations are made from the equivalent queueing models of the proposed systems. Then, numerical results on the performance of the multiplexers are obtained by using the Gauss-Seidel iteration method. These results show that there exist tradeoffs between data and voice traffic performances for a given input traffic load and the output channel rate. 相似文献
777.
Rupsankar Chakrabarti & Badiveddy Madhusudana Rao 《International Journal of Food Science & Technology》2008,43(1):179-184
The annual inland fish production in India is 3.2 million tonnes and above. Aquaculture is around 80% of total inland fish production. The enhanced aquaculture production demands alternate processing methods for better utilisation of the farmed fish. Cirrhinus mrigala is one of the dominated species among cultured Indian major carps, but rated with lowest price. Fish meat with good gel‐forming capacity is a prerequisite in the production of fast‐moving fabricated analogue product. Cirrhinus mrigala had the highest gel strength, i.e. 435 gcm of its fresh meat in comparison with other carps. Apart from the highest protein and salt‐soluble protein nitrogen content in fresh C. mrigala meat, this article also reports that the presence of the darkest thick band of myosin heavy chain and actin in the polyacrylamide gel electrophoresis pattern of salt‐soluble extract of C. mrigala might be another possible reason for the highest gel strength in comparison with other carps. Cirrhinus mrigala contained white meat around 90%. This carp could be suitably used in the preparation of high‐valued fabricated analogue product. 相似文献
778.
Results of an investigation dealing with the behaviour of grid-connected induction generators (GCIGs) driven by typical prime movers such as mini-hydro/wind turbines are presented. Certain practical operational problems of such systems are identified. Analytical techniques are developed to study the behavior of such systems. The system consists of the induction generator (IG) feeding a 11 kV grid through a step-up transformer and a transmission line. Terminal capacitors to compensate for the lagging VAr are included in the study. Computer simulation was carried out to predict the system performance at the given input power from the turbine. Effects of variations in grid voltage, frequency, input power, and terminal capacitance on the machine and system performance are studied. An analysis of self-excitation conditions on disconnection of supply was carried out. The behavior of a 220 kW hydel system and 55/11 kW and 22 kW wind driven system corresponding to actual field conditions is discussed 相似文献
779.
780.