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941.
Published data on the preparation procedures, stability, and complexation of U(III) in aqueous solutions are summarized and correlated. Reactions with inorganic and organic free radicals studied by the flash radiolysis method, the spectroscopic properties, the extraction and ion-exchange behavior of U(III), and methods for isolation of solid U(III) compounds from aqueous solutions are discussed. 相似文献
942.
943.
Among engineers and scientists, MATLAB is one of the most popular computational packages. Part of MATLAB's popularity stems from its simple, yet sophisticated, graphics capabilities. While basic plots are relatively easy to obtain, specialized plots require a little more effort to produce. This article introduces MATLAB's Handle Graphics, which provides a mechanism to fully control and customize graphics objects in MATLAB. With a basic understanding of Handle Graphics, users can produce plots that meet the unique needs and quality standards commonly required by the profession, several examples are presented to illustrate the concepts. 相似文献
944.
945.
The results of studying the effect of nontraditional additives, namely, metallic aluminum and zinc powders on the process
of silicate and glass formation using polythermal and thermogravimetric analysis, are described. The specifics of the glass-melting
process for decorative glasses using the nontraditional additives are considered.
__________
Translated from Steklo i Keramika, No. 5, pp. 7 – 10, May, 2005. 相似文献
946.
IR spectroscopic and x-ray phase analysis established the structural specifics of glasses in the system Na2O-SiO2-TiO2-Na3AlF6, as well as the dependence on the type of crystallizing phases on the chemical composition of the glass matrix. The effect of the structure of titanium-bearing clusters on the leachability of glasses, the effect of the second coordination sphere on the coordination of the central cation (Ti4+), and the propensity of experimental glass coatings to opacification are registered. 相似文献
947.
O. A. Dolgopolov 《Glass and Ceramics》2005,62(5-6):155-156
Magnetic roll separators on rare-earth magnets are suitable for removing iron impurities from various materials. The advantages
of these magnetic separators over traditional ones are demonstrated.
__________
Translated from Steklo i Keramika, No. 5, p. 33, May, 2005. 相似文献
948.
949.
950.
We formulate a class of difference schemes for stiff initial-value problems, with a small parameter ε multiplying the first derivative. We derive necessary conditions for uniform convergence with respect to the small parameter ε, that is the solution of the difference scheme uih satisfies |uih−u(xi)| Ch, where C is independent of h and ε. We also derive sufficient conditions for uniform convergence and show that a subclass of schemes is also optimal in the sense that |uih−u(xi)| C min (h, ε). Finally, we show that this class contains higher-order schemes. 相似文献