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971.
水体中苯胺类化合物测定方法的改进 总被引:1,自引:0,他引:1
本文分别利用活性炭吸附、三氯甲烷萃取和前两种方法联用对显色剂 N-(1 -萘基 )乙二胺进行了提纯 ,从而使水体中苯胺类化合物测定方法的显色时间由 1 2 0 min(未提纯法 )缩短至 90 min(经三种方法提纯 ) ,显色剂溶液的稳定性有了明显的提高 ,测定方法的精密度得到了显著的改善 ,同时检出限也由 0 .3 0 mg/L (未提纯法 )分别降至 0 .0 48mg/L (活性炭吸附提纯法 )、0 .0 59mg/L(三氯甲烷萃取提纯法 )和 0 .0 3 1 mg/L(两种方法联用提纯法 ) ,用经三种方法提纯后的显色剂溶液测定水样中的苯胺 ,测定结果均令人满意 相似文献
972.
A brown coal, peat and oil shale were subjected to a rapid pyrolysis process and medium-heat-value gases together with tar were collected. The char residue was of high activity and suitable for gasification to create a two-stage gasification system. The coal-tar is used for manufacturing liquid fuels and chemicals. 相似文献
973.
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
974.
正1 RecurDyn如何在仿真之前检查模型的各种设置是否正确?在动力学分析之前,若要检验样机,可以先进行运动学分析,且在施加作用力之前确定各种约束是否正确.在RecurDyn中,还提供模型预分析功能,在simulation type中有预分析功能(pre analysis),检查模型自由度、是否有冗余约束及其相关信息.2 RecurDyn怎样解决有冗余约束的问题?当模型存在冗余约束时,软件在求解过程中会 相似文献
975.
Yong-Zhao Wang Yong-Xiang Zhao Chun-Guang Gao Dian-Sheng Liu 《Catalysis Letters》2007,116(3-4):136-142
Without use of any surfactant or oxidant, a series of Co3O4 catalysts have been prepared from cobalt nitrate aqueous solution via a very simple liquid-precipitation method with ammonium
acid carbonate followed by calcination at various temperatures. The catalytic performance of the Co3O4 for CO oxidation has been studied with a continuous flowing laboratory microreactor system. The results show that the CO
conversion of all the samples can reach 100% at ambient temperature. The catalyst calcined at 300 °C is able to maintain its
activity for CO complete oxidation more than 500 min at 25 °C and about 240 min even at −78 °C. High reaction temperature
results in a high catalytic stability, while the catalytic stability decreases with further increasing the reaction temperature.
Characterizations with X-ray powder diffraction and transmission electron microscopy suggest that all the samples exist as
a pure Co3O4 phase with the spinel structure, the samples are apt to aggregate and the specific surface area gradually decreases with
increasing the calcination temperature, which directly leads to the decrease of catalytic stability. Furthermore, the amount
of active oxygen species measured by CO titration experiments appears to be critical for catalytic performance. 相似文献
976.
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
977.
轻质油品氧化脱硫技术进展 总被引:9,自引:1,他引:9
介绍了国内外轻质油品氧化脱硫技术的研究进展情况,分析了选择性氧化脱硫、超声波氧化脱硫、光催化氧化脱硫、等离子体液相氧化脱硫等技术的优缺点,展望了氧化脱硫技术应用前景。 相似文献
978.
Hua Zhao 《Chemical Engineering Communications》2006,193(12):1660-1677
Over the past decade, ionic liquids (ILs) have become one of the fastest growing “green” media for chemists and engineers due to their superb physicochemical properties. The applications of these remarkable salts in reactions and extraction processes have been extensively investigated and reviewed. This review, however, highlights recent advances of ILs as versatile “green” engineering liquids in a variety of industrial applications including heat transfer fluids, azeotrope-breaking liquids, lubricants, electrolytes, liquid crystals, supported IL membranes, plasticizers, and more. This review is not intended to be comprehensive, but rather to discuss the potentials of ILs for diverse industrial applications. 相似文献
979.
980.
自行设计了一台单填料函滑动管板式换热器代替进口设备,运转良好。本文着重介绍该设备密封结构的设计。 相似文献