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991.
C. N. Cacaval E. C. BuruianÎ D. Rou E. Rusu G. E. Grigoriu V. Brboiu 《Polymer International》1985,17(4):343-346
Thermogravimetry and pyrolysis in combination with gas chromatography and infrared spectroscopy were the experimental techniques applied to the thermal degradation of cinnamoylated poly(vinyl alcohol) samples, constituted from vinyl alcohol-vinyl cinnamate photocrosslinkable copolymers. The thermal decomposition products include gases, liquids and solids. The gases are formed from saturated and unsaturated volatile hydrocarbons C1? C4, carbon monoxide and carbon dioxide. The liquid fraction includes aromatic hydrocarbons and some oxygenated organic compounds. The solid product identified in the greatest amount was cinnamic acid. The content in the thermal decomposition products varies considerably both with copolymer composition and temperature. 相似文献
992.
The viscoelastic properties of a three-arm and a four-arm star polybutadiene with the same arm molecular weight (Ma) were studied. The zero-shear recoverable compliance (J0e) and plateau modulus (G0N) for these stars are the same. The zero-shear viscosity (η0) of the three-arm star is 20% lower than that of the four-arm star. Mixtures of the stars had J0e and G0N unchanged. A mixture of the three- and four-arm star was diluted with a low molecular weight linear polybutadiene. G0N∝ø2; J0e∝ø?1 and Me∝ø?1, as expected for dilution with a θ-solvent. 相似文献
993.
The noise generated by a ball mill during a batch grinding operation is investigated and the results show that, for a given ore, the noise levels may vary with time of grind, ore charge weight and mill speed. The role of the ore in absorbing noise energy is suggested as a possible control variable for the grinding process and as an indicator of product size distribution. The relationship between ore types and mill noise is also examined and, under conditions of wet grinding, it is demonstrated that mill noise analysis can indicate ore type and may have a possible use as a grindability-type parameter. 相似文献
994.
995.
N. N. Aizenberg É. I. Gergo Yu. L. Ivas'kiv I. V. Semion 《Cybernetics and Systems Analysis》1991,27(4):491-496
We propose a new class of tunable logic modules that realize functions of k-valued logic. These modules are characterized by homogeneous structure and linear dependence of the number of tunable inputs on the number of input variables.Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 24–29, July–August, 1991. 相似文献
996.
997.
B. L. WEDZICHA S. GODDARD D. N. GARNER 《International Journal of Food Science & Technology》1987,22(6):653-657
When sulphur dioxide inhibits the enzymic browning of catechol catalysed by mushroom tyrosinase, the main reaction product is 4-sulphocatechol. When assessed for its browning potential, this product appears to be unreactive and does not inhibit the enzyme. 相似文献
998.
By applying a high-reflectivity metal coating to the rear facet of a GaAs-based quantum cascade laser operating at /spl lambda//spl sim/11.5 /spl mu/m, the threshold current has been reduced by 11% at 260 K and pulsed operation of the epilayer-up mounted device was extended from 283 to 294 K. 相似文献
999.
Many of the targeted applications for powder-metallurgy materials, particularly in the automotive industry, undergo cyclic
loading. It is, therefore, essential to examine the fatigue mechanisms in these materials. The mechanisms of fatigue-crack
initiation and propagation in ferrous powder-metallurgy components have been investigated. The fatigue mechanisms are controlled
primarily by the inherent porosity present in these materials. Since most, if not all, fatigue cracks initiate and propagate
at the specimen surface, surface replication was used to determine the role of surface porosity in relation to fatigue behavior.
Surface replication provides detailed information on both initiation sites and on the propagation path of fatigue cracks.
The effect of microstructural features such as pore size and pore shape, as well as the heterogeneous microstructure on crack
deflection, was examined and is discussed. Fracture surfaces were examined to elucidate a mechanistic understanding of fatigue
processes in these materials. 相似文献
1000.
V. V. Skurat N. M. Shiryaeva N. K. Myshkina A. A. Gvozdev G. Z. Serebryanyi N. B. Golikova 《Journal of Engineering Physics and Thermophysics》2002,75(5):1200-1206
Unsatisfactory conditions of storage of decontamination waste (DW) in the storages formed in the territory of Belarus after the Chernobyl accident require the evaluation of the level of protection of the environment and population. The potential hazard of the decontamination waste burial grounds (DWBGs) has been evaluated based on the use of a generalized multichamber model that was verified by comparing the calculation results and the results obtained by the American (GW SCREEN) model. The characteristics of the 24 largest and most hazardous DWBGs are given and the evaluations of their safety are presented. The zones of influence of these storages, whose size varies from 100 to 330 m, have been determined. The reliability of the prediction evaluation of a possible hazardous radioactive contamination of water near the storages has been verified using the Dudichi DWBG as an example. 相似文献