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991.
Ye Wan Wenhui Guo Jin Xiao Dazhou Yan Xiong Zhao Shuhu Guo Jianhua Liu Qifan Zhong Tao Yang Yu Zhao Xin Chang Xin Gao 《中国化学工程学报》1982,28(9):2248-2255
Ultra-high-purity silicon tetrachloride (SiCl4) is demanded as an electronic-grade chemical to meet the stringent requirements of the rapidly developing semiconductor industry. The high requirement for ultra-high-purity SiCl4 has created the need for a high-efficient process for reducing energy consumption as well as satisfying product quality. In this paper, a mass of production technology of ultra-high-purity SiCl4 was successfully developed through chlorination reaction in the ultraviolet (UV)-based photo microreactor coupled with the distillation process. The influences of key operational parameters, including temperature, pressure, UV wavelength and light intensity on the product quality, especially for hydrogen-containing impurities, were quantified by the infrared transmittance of Fourier transform infrared spectroscopy (FT-IR) at 2185 cm-1 and 2160 cm-1 indicating that characteristic vibrational modes of Si—H bonds, as well as the operating conditions of distillation were also investigated as key factors for metal impurities removing. The advanced intensification of SiCl4 manufactured by the integration of photo microreactor and distillation achieves the products with superior specifications higher than the standard commercial products. 相似文献
992.
针对轮胎帘布裁断机监控系统功能单一、集成化和智能化程序低的现状,采用虚拟仪器开发平台LabVIEW,在IPC+PLC硬件架构上开发了实时EtherNet/IP工业以太网通信的监控与故障诊断专家系统.通过故障树分析,建立裁断机故障树模型并计算最小割集以及相应重要度,建立了专家系统知识库,解决了专家系统知识库获取难的问题.基于故障树割集重要度的推理机推理过程简洁直观,灵活通用.设计的裁断机监控系统交互界面简明清晰,故障诊断快速准确,在厂测试和设备交付后的反馈情况表明,系统能有效缩短设备故障停机检修时间,提高了设备利用率. 相似文献
993.
Laiyuan Chen Liwu Lin Zhusheng Xu Tao Zhang Dongbai Liang Qin Xin Pinliang Ying 《Catalysis Letters》1995,35(3-4):245-258
Infrared investigations on the interaction of methane with silica, aluminas (, and ) and HZSM-5 zeolite have been carried out. At low temperature (173 K), methane adsorption was observed over these oxides and HZSM-5 zeolite. Our findings featured that the infrared inactive
1 band (2917 cm–1) of a gaseous methane molecule became active and shifted to lower frequencies (2900 and 2890 cm–1) when it adsorbed on the surfaces of these adsorbents. Our results also demonstrate that hydroxyl groups played a very important role in methane adsorption over the acidic oxides and the HZSM-5 zeolite. When interaction between the hydroxyl groups and methane took place, the band shift of the hydroxyl groups varied with different oxides. The strength of the interaction decreased according to the following sequence, Si-OH-Al>Al-OH>Si-OH, which is in accordance with the order of their acidities. At higher temperatures, methane interacted quite differently with various oxides and HZSM-5 zeolite. It has been observed that the hydroxyl groups of silica, -alumina and HZSM-5 zeolite could exchange with CD4 at temperatures higher than 773K, while those on -alumina could exchange at a temperature as low as 573 K. Another interesting observation was the formation of formate species over Al2O3 (both and ) at temperatures higher than 473 K. The formate species would decompose to CO2, or produce carbonate at much higher temperatures. Formation of formate species was not observed over silica and HZSM-5 under similar conditions, -Al2O3 did not adsorb or react with methane in any case. 相似文献
994.
分析了国内外二甲基亚砜的消费市场情况,介绍了二甲基亚砜的生产工艺,对国内发展二甲基亚砜生产技术提出了合理建议。 相似文献
995.
Ye Wan Wenhui Guo Jin Xiao Dazhou Yan Xiong Zhao Shuhu Guo Jianhua Liu Qifan Zhong Tao Yang Yu Zhao Xin Chang Xin Gao 《中国化学工程学报》2020,28(9):2248-2255
Ultra-high-purity silicon tetrachloride (SiCl4) is demanded as an electronic-grade chemical to meet the stringent requirements of the rapidly developing semiconductor industry. The high requirement for ultra-high-purity SiCl4 has created the need for a high-efficient process for reducing energy consumption as well as satisfying product quality. In this paper, a mass of production technology of ultra-high-purity SiCl4 was successfully developed through chlorination reaction in the ultraviolet (UV)-based photo microreactor coupled with the distillation process. The influences of key operational parameters, including temperature, pressure, UV wavelength and light intensity on the product quality, especially for hydrogen-containing impurities, were quantified by the infrared transmittance of Fourier transform infrared spectroscopy (FT-IR) at 2185 cm−1 and 2160 cm−1 indicating that characteristic vibrational modes of SiH bonds, as well as the operating conditions of distillation were also investigated as key factors for metal impurities removing. The advanced intensification of SiCl4 manufactured by the integration of photo microreactor and distillation achieves the products with superior specifications higher than the standard commercial products. 相似文献
996.
抗rHu-IFN-αMcAb亲和常数的测定 总被引:1,自引:0,他引:1
采用ELISA间接法检测抗原-抗体反应系统中游离抗体量的方法,对本实验室制备的5系抗rHu-IFN-αMcAb进行了亲和力测定,获得比较准确的McAb亲和常数。 相似文献
997.
应用基于模糊数学与常规可靠性理论相结合的模糊可靠性设计方法,讨论钢制薄壁内压容器模糊静强度在不同工况时,有关标准可接受的模糊可靠度范围;对钢制薄壁内压容器静强度的模糊可靠度范围与安全系数的关系进行研究。分析认为容器静强度在满足最小模糊可靠度要求的前提下,可取屈服安全系数ns≥1.55与抗拉安全系数nb≥1.95。 相似文献
998.
999.
碳酸二苯酯技术发展现状及展望 总被引:1,自引:0,他引:1
综述了碳酸二苯酯多种合成技术的发展现状,重点介绍了碳酸二甲酯与苯酚酯交换法和氧化羰基化法技术,并对碳酸二苯酯技术在国内的发展进行了展望。 相似文献
1000.
塑料制品的添加剂—成核剂的分类及研究 总被引:2,自引:0,他引:2
成核剂是促进聚合物结晶并改善其晶粒结构的改性剂,它主要包括无机类成核剂、有机类成核剂和高分子类成核剂,在聚合物中加入成核剂,加成了结晶速度,使聚合物的晶粒结构细化,缩短了成形周期,改善了产品的物理机械性能,使产品具有良好的加工和使用性能。 相似文献