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991.
国内二氯苯生产现状及今后发展之我见 总被引:5,自引:0,他引:5
介绍了国内二氯苯3种不同生产式敢,规模及对二氯苯,邻二氯苯的精帛工艺,并分析了国内二氯苯生产装置中存在的问题,详细分析了对二氯苯,邻二氯苯的市场及应用情况,针对国内二氯苯的生产现状及与国外的差距提出了今后发展的建议。 相似文献
992.
993.
The influences of nucleating agent content on crystallization peak temperature, crystallization curve shape, crystallization onset temperature, and crystallinity of a copolypropylene were studied in detail by differential scanning calorimetry. The results showed that crystallization onset temperature and crystallization peak temperature increased 17°C–22°C and 15°C–19°C, respectively, with increasing nucleating agent content. The behavior of the nucleating agent showed excellent efficiency. But the shape of the crystallization curve broadened with increasing nucleating agent content, and the crystallinity came to an extremum when the nucleating agent content was 0.2%. These results generally differed from those for crystallization of i‐PP by a nucleating agent. Modification of copolypropylene was studied by use of a nucleating agent, and the characteristics of the effects of the nucleating agent on copolypropylene were mastered. The results showed that the hardness of a copolypropylene improved observably. So the abrasion resistance of biaxially oriented polypropylene (BOPP) film for cigarette packaging was improved by adopting the modified copolypropylene as the skin‐layer heat‐seal material of BOPP film. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101:3915–3919, 2006 相似文献
994.
995.
996.
粉煤灰饰面玻璃的研制 总被引:6,自引:1,他引:6
利用粉煤灰可制得粉煤灰饰面玻璃,与粉煤灰微晶玻璃相比,其优点是粉煤灰用量高,能耗低,成本低,装饰效果好。本文介绍了实验室与工业性扩大试验的结果,并对生产工艺中的几个问题作了讨论。 相似文献
997.
Yu-Hang Yuan Xing-Gui Zhou Wei Wu Yi-Ran Zhang Wei-Kang Yuan Lingai Luo 《Catalysis Today》2005,105(3-4):544-2
Gas phase propylene epoxidation on gold catalysts has attracted wide attention from industry and academia due to its high selectivity. However, it suffers from low propylene conversion and rapid catalyst deactivation. Experiments showed that propylene conversion could be increased by raising H2, O2, or C3H6 concentration in the feed, but the feed compositions were within the explosion limit. It was also shown that the activity of the used catalyst could be fully recovered, but the regeneration temperature was 280 °C, much higher than that for reaction. Therefore a microchannel reactor was devised to suppress explosion and was constructed with Fecralloy, to raise the temperature rapidly for catalyst regeneration by electric heating. In two minutes the temperature of the reactor could be raised from 50 to 300 °C. Catalysts were coated on the alloy belt by dip coating, and the performance of the reactor was evaluated under different operating conditions. Results showed that in the microreactor the overall reaction rate was controlled mainly by the intrinsic reaction rate, and also influenced by film diffusion to a certain extent. The deactivated catalyst was regenerated in the microchannel reactor and the activity was fully recovered. 相似文献
998.
The rheological behaviors of high‐impact polystyrene (HIPS) and HIPS/TiO2 composites were investigated by use of a rheometer in the present article. HIPS exhibited a constant critical stress of the sharkskin in various temperatures, and the analysis indicated that the mechanism of sharkskin of HIPS was wall–slip and its special temperature dependency was determined by weak wall–melt adsorption. The experimental results also showed that the introduction of TiO2 into HIPS only slightly influenced the apparent viscosity (ηa) of the composites. Moreover, TiO2 exhibited an unusual effect on the non‐Newtonian index of the composites at high shear rate. Both phenomena indicated the increase of inner free volume induced by TiO2 in molecularly rigid HIPS. Moreover, it was noteworthy that a featured stress could be used to label the dispersion of TiO2 in the HIPS matrix, and the numeric affinity of this featured stress and the critical stress of sharkskin revealed that both processes were relevant to the same molecular relaxation. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 802–807, 2005 相似文献
1000.
The quantity of computer applications is increasing dramatically as the computer industry prospers. Meanwhile, even for one application, it has different requirements of performance and power in different scenarios. Although various processors with different architectures emerge to fit for the various applications in different scenarios, it is impossible to design a dedicated processor to meet all the requirements. Furthermore, dealing with uncertain processors significantly aggravates the burden of programmers and system integrators to achieve specific performance/power. In this paper, we propose elastic architecture (EA) to provide a uniform computing platform with high elasticity, i.e., the ratio of worst-case to best-case performance/power/performance-power trade-off, which can meet different requirements for different applications. It is achieved by dynamically adjusting architecture parameters (instruction set, branch predictor, data path, memory hierarchy, concurrency, status~zcontrol, and so on) on demand. The elasticity of our prototype implementation of EA, as Sim-EA, ranges from 3.31 to 14.34, with 5.41 in arithmetic average, for SPEC CPU2000 benchmark suites, which provides great flexibility to fulfill the different performance and power requirements in different scenarios. Moreover, Sim-EA can reduce the EDP (energy-delay product) for 31.14% in arithmetic average compared with a baseline fixed architecture. Besides, some subsequent experiments indicate a negative correlation between application intervals' lengths and their elasticities. 相似文献