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<正>众所周知,蜡可以防止硫化橡胶制品臭氧降解。因此,防护蜡可以延长产品的使用寿命,防止老化或龟裂。图1示出了蜡作为抗臭氧剂的作用机理。首先,由于橡胶分子的活跃运动,橡胶制品中的蜡迁移到橡胶表面;其次,由于喷霜,橡胶制品的表面形成蜡层。由此产生的蜡层可以防护橡胶制品免受臭氧的破坏;也就是说,它可以作为防护层,防止橡胶与臭氧发生反应。在实践中,通过在橡胶制品的表面形成蜡层可提高静态条件下的橡胶制品在室温下的抗臭氧性。 相似文献
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研究不同碳数分布防护蜡在轿车子午线轮胎胎侧胶中的应用。结果表明:防护蜡A—C的熔点、峰值碳数及异构烷烃含量依次增大,双峰防护蜡D的异构烷烃含量较小;不同碳数分布防护蜡对胶料的硫化特性和物理性能影响不大;防护蜡B胶料的耐臭氧老化性能最优,防护蜡A胶料的臭氧防护效果较差;23℃时防护蜡A胶料的抗喷霜效果较好,30℃时防护蜡B胶料的抗喷霜性能最佳,60℃时不同防护蜡的抗喷霜性能相近;添加防护蜡B的胶料耐臭氧老化性能和抗喷霜性能及成品轮胎的外观质量均较好。 相似文献
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本文通过对国产橡胶防护蜡与进口橡胶防护蜡在炭数分布,实际耐臭氧性能以及对胶料物理机械性能的影响进行对比,实验表明,国产橡胶防护蜡L5866无论在炭数分布,实际耐臭氧性能还是对胶料物理机械性能影响方面接近或达到进口橡胶防护蜡的水平。这说明国产橡胶防护蜡L5866完全可以替代进口橡胶防护蜡。 相似文献
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介绍橡胶防护蜡的组成、防护机理、防护效果的影响因素以及研究进展与应用现状。普遍使用的橡胶防护蜡是由石蜡和微晶蜡调配而成的混合蜡;橡胶防护蜡迁移到橡胶表面形成一层致密的保护薄膜,阻挡臭氧分子对橡胶大分子的攻击;橡胶防护蜡的碳数分布和正构烷烃/异构烷烃的比例对其在橡胶表面的防护效果影响较大,其熔点和环境温度也对其迁移有影响。国内橡胶防护蜡产品虽然有了一定的进步和发展,但在产品特性和质量方面与进口橡胶防护蜡产品存在一定的差距,稳定橡胶防护蜡产品原材料的质量以及其与不同橡胶及助剂体系的综合性研究是今后橡胶防护蜡产品开发方向之一。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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塔设备改造选型的分析 总被引:2,自引:0,他引:2
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。 相似文献