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用择形催化剂XC-90催化α-蒎烯异构化反应,考察了反应时间、反应温度对反应结果的影响,研究了该反应的动力学,求出了反应的表观活化能、频率因子和反应级数,建立了反应速率常数与温度的关系式 相似文献
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本文详细阐述了以环己胺,间苯二酚,硫酸二甲酯,苯酐为主要原料,经缩合反应,烷基化反应,酰化反应来合成热敏染料TCT-2,并且给出了最佳操作条件缩合反应206~208℃,回流反应5小时;烷基化反应50℃反应2小时;酰化反应回流反应7小时。 相似文献
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提出了隔壁反应精馏合成碳酸甲乙酯的新工艺,除考虑碳酸二甲酯与乙醇酯交换反应外,还考虑了碳酸二甲酯与碳酸二乙酯反歧化反应的影响,并集成上述反应于一台隔壁反应精馏塔中,优化了碳酸甲乙酯的生产过程。首先,进行了碳酸二甲酯与碳酸二乙酯反歧化反应动力学实验,建立反应动力学模型,并验证了该工艺流程中此模型计算结果的可靠性。然后,运用Aspen Plus对隔壁反应精馏新工艺进行了流程模拟和优化设计,分别确定了酯交换反应段、反歧化反应段、产品精馏段和公共提馏段的理论塔板数,最佳进料位置、回流比等主要操作参数。隔壁反应精馏新工艺与常规反应精馏三塔工艺相比,新工艺将塔釜产品碳酸二乙酯返回隔壁塔内,增加了反歧化反应区,显著提高了碳酸甲乙酯选择性和收率,避免了低价值副产物碳酸二乙酯的产生,并有效减少了设备投资和运行能耗。 相似文献
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采用自制聚酯A与甲苯二异氰酸酯(TDI)进行反应,合成了聚氨酯(PU)预聚体,再与3-N(苯基)氨基丙基三甲氧基硅烷进行封端反应,合成了硅烷封端聚氨酯热熔胶(SPUR)。通过化学分析法分别研究了PU预聚体和SPUR的反应动力学。结果表明,聚酯A与TDI的预聚反应为二级反应,反应活化能Ea为33.82kJ/mol,75℃下反应速率常数k为0.00732g/(mol.min),反应末期由于粘度增大和支化反应,偏离了二级反应;PU预聚体与3-N(苯基)氨基丙基三甲氧基硅烷的反应也为二级反应,反应速率常数k为0.0827g/(mol.min),反应速率快,可在室温下快速反应。 相似文献
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Guidelines for the successful use of ozone as a stand-alone cooling tower water treatment method are discussed. Included are recommendations for system sizing, proper ozone residuals, mixing and distribution of the ozonated water, and potential problems and solutions. These include excessive or insufficient cycles of concentration, chemical contamination, low flow rates, high heat exchanger temperatures, and extended system turnover times. Also discussed are recommended maximum system downtimes, preferred types of towers and heat exchangers to treat with ozone, use of filtration systems, and elastomer compatibility with ozone. System monitoring and maintenance procedures are discussed along with ozonation safety considerations. With this information, two recently reported ozonation system failures are analyzed and the causes of failure are discussed. 相似文献
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为了实现石脑油的高效资源化利用,需开发石脑油高效分离技术。简述了石脑油正/异构烷烃吸附分离原理及分离技术现状,介绍了新型吸附剂材料的研发进展,包括金属有机框架材料(MOFs)、沸石咪唑框架材料(ZIFs)、碳分子筛(CMS)、中空沸石分子筛等,阐述了新型吸附材料对正构烷烃的分离效果和分离机理,探讨了新型吸附剂、膜分离技术和吸附-膜分离耦合技术用于分离石脑油中正/异构烷烃的可行性,展望了新型正/异构烷烃分离技术,以期为石脑油高效资源化利用提供新途径。 相似文献
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C Barnes 《Coloration Technology》1984,14(1):127-131
The traditional recipes for metal coloration are briefly mentioned and the problems associated with these processes are discussed. The important developments since 1945 are reviewed; particular attention is paid to the industrial processes that have become established for the coloration of aluminium, stainless steel, zinc and gold. Processes for the blackening of metals for use as solar collectors are also discussed. 相似文献
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Electrochemistry and the environment 总被引:50,自引:0,他引:50
Advances in electrochemical methods for pollutant remediation, recycling and sensing are reviewed. Additionally, applications of these methods in the drinking water industry, and for disinfection scenarios are discussed. Lastly, new electrode materials for environmental applications are described. In a companion review, photoelectrochemical methods will be discussed. 相似文献
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就耐腐蚀结构的过滤洗涤干燥三合一机的研究和开发进行了详细论述。着重论述了该机主要零部件的结构设计和材料选用,分析了该机的结构特点。 相似文献
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The mechanism of, and requirements for, the dyeing of wool at low temperature are discussed, and two-bath processes that satisfy these requirements are evaluated. A new one-bath process for the rapid dyeing of wool at 50 or 60°C is described and evaluated, and ways of re-using dye-liquors are discussed. 相似文献