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881.
882.
The study and creation of the infrastructure required to enable system-level science--the integration of diverse sources of knowledge about the constituent parts of a complex system with the goal of obtaining an understanding of the system's properties as a whole--is becoming increasingly important, spawning new knowledge in variety of fields at a rapid pace. 相似文献
883.
Necessary and sufficient conditions are found for continuous and periodic liquid motion in systems containing siphons.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 52, No. 6, pp. 916–920, June, 1987. 相似文献
884.
885.
886.
The conditions for a rather fast increase in parametric thermomechanical oscillations have been revealed by using numerical solutions of some types of Hill's equation. It is shown that the occurrence of a real parametric resonance is essentially determined by the character of thermal modulations. It is hypothesized that the indicated trends are observed in oscillations of any physical nature.Stavropol State Pedagogical Institute, Stavropol. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 63, No. 3, pp. 294–298, September, 1992. 相似文献
887.
The paper describes the synthesis of N-2/4-toluyl methacrylatoethyl carbamates using 2/4-toluyl isocyanate and 2-hydroxyethyl methacrylate. Homopolymerisation and copolymerisation of these novel monomers with methyl methacrylate was carried out using benzoyl peroxide as an initiator and tetrahydrofuran as solvent. Photopolymerisation of N-4-toluyl methacrylatoethyl carbamate could be carried out without the use of photosensitiser. Structural characterisation of copolymers was done using 1H-NMR. Thermal stability of copolymers was evaluated in a nitrogen atmosphere by dynamic thermogravimetry. 相似文献
888.
G. A. Isaak'yan V. Ya. Alekseev A. I. Ivanov N. I. Karmalitsyn A. E. Kochin T. E. Sazonova S. V. Sepman I. F. Uchevatkin V. I. Fominykh 《Atomic Energy》1992,73(5):903-907
Mendeleev All-Union Metrology Research Institute. Translated from Atomnaya Énergiya, Vol. 73, No. 5, pp. 393–397, November 1992. 相似文献
889.
I. R. Tatur D. A. Yakovlev I. A. Timokhin L. R. Berezovskii G. B. Prigul'skii V. A. Lazarev V. N. Sergeev 《Chemical and Petroleum Engineering》1992,28(10):623-627
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 10, pp. 29–31, October, 1992. 相似文献
890.
A method has been developed for assay of deoxynivalenol (DON) and its metabolite desepoxideoxynivalenol (DOM-1) in animal excrements with the use of reversed-phase high-performance liquid chromatography with UV-detection (218 nm). The method includes purification in the mini-column with activated carbon and aluminium oxide. The detection limit was 50 ng/g, relative standard deviation--0.05-0.1, the degree of toxin isolation--76-89%. DON isolated from Fusarium macroceras, strain 579a, cultivated in rice under laboratory conditions, and DOM-1 obtained as a result of DON incubation with the contents of the beef first stomach, were used in the study. The structure of toxins isolated has been proved by the mass-spectrometry method. The method developed by the authors was used in the study of DON metabolism in vivo in monkeys. 相似文献