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91.
We have established general quantitative relationships linking the magnitude of the induction period in isothermal and nonisothermal regimes of oligomer hardening for the case in which the nonisothermicity is determined by the kinetics of heat generation in the chemical reaction.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 56, No. 4, pp. 591–595, April, 1989. 相似文献
92.
A. Ya. Aronson 《Strength of Materials》1989,21(3):296-300
PO Leningrad Metallurgical Plant. Translated from Problemy Prochnosti, No. 3, pp. 25–28, March, 1989. 相似文献
93.
V. S. Grebneva V. A. Ermishkin D. L. Krasavin S. Ya. Misevra R. D. Strokatov 《Strength of Materials》1992,24(10):593-598
The commercial alloy 36NKhTYu in various structural conditions differing in the type of decomposition, grain size, and degree of dispersion of Y'- and -phase hardening particles was investigated by high-voltage electron microscopy and determination of the mechanical properties in tension in fatigue tests. It was established that in the alloy with the original coarse grain size regardless of the type of structure being formed and the form of loading, fracture is primarily ductile, occurring by a dislocation-shear mechanism. The comparison of structures of different type that was made showed that the structure with interrupted precipitation of -phase has the highest fracture energy requirement as the result of the presence of plastic interlamellar layers, providing effective dissipation of the energy supplied in loading. Deformation and fracture of the fragmented and ultradispersed structures is controlled by collective rotational processes.Translated from Problemy Prochnosti, No. 10, pp. 23–28, October, 1992. 相似文献
94.
赵勋 《计算机光盘软件与应用》2012,(3):3+11
本文主要介绍RFDI技术定义及系统工作原理,并重点关注RFID技术在智能交通领域的实际应用方式。同时RFID技术也成功解决了车辆自动识别和信息采集问题,为智能交通管理和服务系统的建立提供了强大的信息支撑和保障。 相似文献
95.
The characterization of La
x
Sr1−x
MnO3 powders produced by spray pyrolysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observation,
specific surface area (Brunauer-Emett-Teller), and particle size distribution measurements shows that the resultant large
particles are loose agglomerates consisting of many small particles. However, the sintered tiny particles can form hard agglomerates,
and the particle size increases remarkably. The structures of the powders before and after sintering were identified by x-ray
diffraction (XRD). The study of the electrical property of the powder shows that the powder is a metallic conductor. In a
reducing atmosphere, the powder can be decomposed. When the powder is cofired with yttria-stabilized zirconia 5% (YSZ) powder
at 1200 °C for 5 h, no new phase is produced, and the powder remains a single provskite hexagonal-rhombohedral structure. 相似文献
96.
97.
98.
Pipelines and heat exchangers using seawater as coolant suffer from biofouling. Biofouling not only reduces heat transfer performance significantly, but also causes considerable pressure drop, calling for higher pumping requirements. It would be much more desirable if surfaces with an inherently lower stickability for biofouling could be developed. In this paper, a cost-effective autocatalytic graded Ni-Cu-P-PTFE composite coating with corrosion-resistant properties was applied to reduce biofouling formation. The experimental results showed that the surface free energy of the Ni-Cu-P-PTFE coatings, which were altered by changing the PTFE content in the coatings, had a significant influence on the adhesion of microbial and mineral deposits. The Ni-Cu-P-PTFE coatings with defined surface free energy reduced the adhesion of these deposits significantly. The anti-bacterial mechanism of the composite coatings was explained with the extended DLVO theory. 相似文献
99.
IR spectra of ultrafine diamonds produced by different teams of researchers are studied. The effects of heating and radiation on the properties of ultrafine diamonds are studied. Quantitative assumptions on the kinetics of formation of ultrafine diamonds are made from analysis of IR spectra. 相似文献
100.