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991.
992.
本文综述了氟化物玻璃中的分相研究。在前人研究基础上应用透射电镜,X射线能谱,电子能量损失谱及X射线衍射,差热分析等研究了锆钡镧铝氟化物玻璃中的液-液分相,发现此种现象普遍存在于该类玻璃之中。对玻璃成分与分相形貌及微观结构之间的关系、对析出晶相种类及分相与析晶的相互影响进行了研究。提出欲降低氟化物玻璃的光损耗,分相与析晶一样是不容忽视的因素。 相似文献
993.
The method of coprecipitation of components was used to obtain disperse powders of tetragonal zirconium dioxide stabilized by Y2O3, Yb2O3 and a combined additive (Y2O3 + CaO + MgO). The technological parameters of the processes of synthesis and preparation of initial ZrO2 powders intended for ceramics with elevated strength parameters are proposed. 相似文献
994.
995.
The authors describe an integrated processor that performs addition and subtraction of 30-b numbers in the logarithmic number system (LNS). This processor offers 5-MOPS performance in 3-μm CMOS technology, and is implemented in a two-chip set comprising 170 K transistors. Two techniques are used to achieve this precision in a moderate circuit area. Linear approximation of the LNS arithmetic functions using logarithmic arithmetic is shown to be simple due to the particular functions involved. A segmented approach to linear approximation minimizes the amount of table space required. Subsequent nonlinear compression of each lookup table leads to a further reduction in table size. The result is that a factor of 285 reduction in table size is achieved, compared to previous techniques. The circuit area of the implementation is minimized by optimizing the table parameters, using a computer program that accurately models ROM area. The implementation is highly pipelined, and produces one result per clock cycle using a ten-stage pipeline 相似文献
996.
Yu. M. Mosin I. A. Zakharov E. O. Lavrova M. A. Voinova 《Refractories and Industrial Ceramics》1992,33(1-2):38-43
Conclusions It is shown that in technically suitable conditions for shaping blanks by centrifugal casting, the deposition of the particles occurs with a streamline schedule, and the coarse fractions are deposited during acceleration of the rotation of the mold. The main factor influencing the density of the finely dispersed blanks is the duration of rotation, and for systems containing coarse filler, centrifugal acceleration. Regulating the dimensions (wall thickness) of the blank is possible by altering the concentration of solid phase in the slip and the degree of filling of the mold with it.Translated from Ogneupory, No. 1, pp. 22–24, January, 1992. 相似文献
997.
998.
A compact method of calculation for solving a fundamental problem in structural chemistry — the problem of optimizing the geometric structure of molecular systems — is proposed. Solution of this problem will allow predicting a number of properties of polymer systems based on the existence of a structure—property correlation. It should be noted that the proposed method allows performing all calculations in analytical form. 相似文献
999.
Translated from Steklo i Keramika, No. 12, p. 12–14, December, 1991. 相似文献
1000.
Dr. A. N. Danilenko V. Yu. Vetrov A. P. Dmitrochenko A. L. Leontiev E. E. Braudo V. B. Tolstoguzov 《Molecular nutrition & food research》1992,36(2):105-111
Thermodynamic properties of aqueous solutions of both native and modified legumin of broad beans (Vicia faba L.) have been examined. A restricted trypsin-induced proteolysis was used to modify protein structure. Evaluation of protein affinity to ficoll in aqueous solutions showed that modified protein possessed higher hydrophilicity. Thermodynamic properties of diluted solutions were used to predict the phase behaviour in concentrated systems containing protein and ficoll. At specific concentrations of native legumin, the system can separate in two phases, whereas in the case of modified protein the single-phase behaviour of the system was predicted for any concentrations of both components. The experimental data obtained in concentrated systems confirmed predictions of thermodynamic analysis of diluted solutions. 相似文献