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1.
Hydrogen Permeability of Borosilicate Glasses 总被引:1,自引:0,他引:1
E. F. Medvedev 《Glass and Ceramics》2002,59(7-8):224-227
Borosilicate glass-forming compositions R2O – B2O3 – SiO2 – RaOb (R — Li, Na, K; Ra — Zn, PbO) are investigated. A correlation-regression analysis of the criteria (the silicate modulus, the oxygen number, the structure cohesion factor, the relative molar volumes of the components) affecting the hydrogen permeability of glasses is carried out. The tendency for permeability variations depending on the component composition and the above specified criteria is identified. 相似文献
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A novel approach to monitoring and control of the coal powder injection in a blast furnace is presented and discussed. Image analysis of video recordings is used as a means to estimate the instantaneous coal flow. Initial experiments at blast furnace number 3 of SSAB Tunnplat AB, Lulea, Sweden, are reported and firsthand results on modeling and control of a single injection line are given 相似文献
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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
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An NMR tracking magnetometer, in which the frequency modulation is used instead of the traditional magnetic modulation, is described. Owing to the proposed digital compensation of modulation shifts, the tracking error is negligibly small and does not exceed the corresponding error for NMR magnetometers with magnetic modulation. The absence of the modulation rings decreases the sizes of the sensors to the utmost and excludes their effect on the surrounding systems. 50%-deuteron saturated solution of lithium chloride in water of 50% deuterons, which is used as a sensor substance, allows one to measure magnetic fields of 0.0625 to 15.3 T with a 10?7 relative error at the most. 相似文献
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DM Kulibaba VN Novozhilov EG Tsvetkov VG Medvedev 《Canadian Metallurgical Quarterly》1997,156(2):117-118
Access and visualization in the implant-abutment area are often compromised. Tissue impingement and lack of abutment position verification may result in inaccurate fit. 相似文献