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991.
A comparative analysis of the information activities of leading scientists has been carried out, including 5 Soviet chemists and 5 foreign ones, and 8 Soviet physicists, specialist in low temperature physics. Within chemists there has appeared a tendency to a new form of scientific activities, namely ephemeron teams which favour the production line mode of getting new information. In physics, the traditional scheme is preserved: leading scientists publish few articles and have few co-authors. The ephemeron teams produce an expanding information: new objects and processes are studied from the previously elaborated point of view. The specific average citation rate (number of references per number of papers) is a criterion for separating the publications of the intellectual industry from the pilot studies full of novel ideas.Repinted from: A. I. MIKHAILOV (Ed.), Problems of Information User Needs, All-Union Institute for Scientific and Technical Information, Moscow, 1973, p. 113–134. 相似文献
992.
余热制冷技术在玻璃工业中的应用探讨 总被引:1,自引:0,他引:1
介绍了两种蒸汽制冷设备的工作原理和特点,并对各自的运行状况作了比较,同时简要分析了在玻璃工业中利用余热制冷的可行性。 相似文献
994.
用初速度法测定了青霉素酰化酶基因工程菌 E.coli A_(56)(pPA22)游离细胞和固定化细胞水解青霉素 G 的动力学常数,并进行了动力学模型的检验。该菌体酶活高,米氏常数小,固定化后米氏常数和苯乙酸抑制常数增大,底物抑制常数和6-APA 抑制常数没有变化。通过青霉素 G 裂解过程的考察,验证了青霉裂解动力学模型的适用性及动力学常数测定的可靠性。 相似文献
995.
L. F. Grigor’eva S. A. Petrov O. Yu. Sinel’shchikova I. A. Drozdova V. V. Gusarov 《Glass Physics and Chemistry》2007,33(1):72-79
The mechanism of formation of barium titanate Ba2Ti9O20 in the BaO-TiO2 and BaO-SrO-TiO2 systems is investigated using initial mixtures prepared by three methods, namely, mechanical grinding of the initial reactants, coprecipitation from aqueous solutions of salts, and the sol-gel technique. It is established that, irrespective of the preparation procedure, the formation of Ba2Ti9O20 proceeds through the formation of the intermediate phases BaTi4O9 and BaTi5O11. The nature of the intermediate phases is determined by the homogeneity and dispersion of the initial mixture, as well as by the stability of the intermediate phase. The most optimum conditions for the synthesis of Ba2Ti9O20 are provided by the formation of BaTi5O11 as an intermediate phase upon heat treatment of the coprecipitation products in the nanocrystalline state. The metastability and structural defects in the BaTi5O11 intermediate phase encourage a decrease in the temperature of the final heat treatment by 100–150°C in the course of the preparation of Ba2Ti9O20 single-phase ceramics. 相似文献
996.
A new derivation of the scale effect equation for polymer fibers is proposed. The equation is: AL
–, where is the average strength of the fiber; L is the length of the fiber; A and are coefficients. The equation was obtained from the general premises of scale effect theory without indication of the concrete form of the probability function F(S).Ukrainian Scientific-Research Institute of Polymer Fibers, Kiev. Translated from Khimicheskie Volokna, No. 4, pp. 34–36, July–August, 1992. 相似文献
997.
中国漆文化遗产保护调查研究之二 总被引:1,自引:0,他引:1
云雕是漆器的一种。通常用红黑两色漆交替髹涂,然后雕刻花纹,刻纹侧面显出红黑相间的线纹。多雕成云状,故又称“云雕”,也即剔犀。 相似文献
998.
999.
Yu. A. Samoilovich 《Journal of Engineering Physics and Thermophysics》1975,29(3):1188-1193
An approximate method is given for calculating the solidification of a complex casting on the basis of a quasistationary approach and the use of conformal transformation. The solution to the two-dimensional Stefan's problem is illustrated by the solidification of a melt in wedges of angle up to 2.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 29, No. 3, pp. 527–534, September, 1975. 相似文献
1000.
Yu. Ts. Oganesyan A. G. Demin A. S. Il'inov S. P. Tret'yakova A. A. Pleve Yu. É. Penionzhkevich M. P. Ivanov Yu. P. Tret'yakov 《Atomic Energy》1975,38(6):492-501
Conclusions A number of conclusions can be drawn from the aggregate of experimental results.The method of synthesis of transfermium elements in the irradiation of lead isotopes with ions with mass AI40 atomic units, investigated earlier [12] for the example of the reaction Pb(40Ar, xn)Fm, is also extremely effective using50Ti ions. The reactions Pb(40Ar, 2n)Fm and Pb(50Ti, 2n)Ku have approximately equal cross sections, which might have been expected on the basis of theoretical estimates. This permits us to hope that this method can be used successfully for the synthesis of heavier elements in the reactions induced by54Cr,55Mn, and58Fe ions.In all probability, the substantial changes in the systematics of the half-lives for even-even isotopes of kurchatovium are associated with the structure of the barriers to fission of these nuclei. From this standpoint, it seems important to investigate the properties of more neutron-deficient isotopes of kurchatovium, using, in particular, the reactions with204Pb, and to attempt to advance into the region of elements with Z 106. On the other hand, a detailed theoretical analysis must be made of the data obtained on the basis of the modern theory of nuclear fission, which, in our opinion, will aid in a more reliable prediction of the properties of heavy and ultraheavy elements.Translated from Atomnaya Énergiya, Vol. 38, No. 6, pp. 382–390, June, 1975. 相似文献