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本文研究了由苯酚与三聚氯氰反应合成2,4,6-三苯氧基-1,3,5-三嗪,然后溴化合成溴代三嗪的反应条件,得到合成2,4,6-三苯氧基-1,3,5-三嗪合适的工艺条件:用氯苯作溶剂,无水三氯化铝做催化剂,苯酚与三聚氯氰在回流温度下保温反应3h。  相似文献   
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Itaconic acid finds a place in various industrial applications. It can be produced by biocultivation in a clean and environment friendly route but recovery of the acid from the dilute stream of the bioreactor is an economic problem. Reactive extraction is a promising method to recover carboxylic acid but suffers from toxicity problems of the diluent and extractant employed. So there is need for a non‐toxic extractant and diluent or a combination of less toxic extractants in a non‐toxic diluent that can recover acid efficiently. Effect of different extractants: trin‐butylphosphate (TBP) (an organophosporous compound) and Aliquat 336 (a quaternary amine) in sunflower oil was studied to find the best extractant–sunflower oil combination. Equilibrium complexation constant, KE, values of 1.789 and 2.385 m3 kmol?1, respectively, were obtained for itaconic acid extraction using TBP and Aliquat 336 in sunflower oil. The problem of toxicity in reactive extraction can be reduced by using a natural non‐toxic diluent (sunflower oil) with the extractant. Copyright © 2010 Society of Chemical Industry  相似文献   
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采用双金属氰化配位物(DMC)催化三(2-羟乙基)异氰脲酸酯(THEIC)、环氧丙烷(PO)、邻苯二甲酸酐(PA)三元共聚反应,得到一种新型的三元聚合物。用核磁共振谱(1H-NMR)和红外(IR)表征了聚合物结构。并以此聚合物为原料制备了聚氨酯硬质泡沫塑料,研究了泡沫塑料的力学性能、热性能和阻燃特性等。结果表明:PA的引入可以有效提高硬质泡沫塑料的拉伸性能;随着PA与PO的摩尔比增大,泡沫塑料的热分解温度提高,氧指数也有所提高。  相似文献   
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The mechanism of plastic forming and processing in electromagnetic dynamic tri‐screw extruder is very sophisticated and the investigation of amplitude–frequency characteristic acts as the foundation of equipment design and the optimization of polymer processing parameters. A mathematical and analytical model of plastic forming in such extruder was developed and the results were nondimensional‐normalized. To validate the mathematical solutions experiments based on LDPE were carried out and the experimental vibration amplitude and vibration frequency curve was obtained. Three conclusions can be drawn herein: (1) the experimental results hold a good agreement with the calculations, and thus the feasibility of the proposed model is validated; (2) the possibility of resonance closely relates to polymer melt viscosity, rotating speed, and geometry parameters of the screw; (3) resonance of the tri‐screw extruder is seldom observed under normal conditions and there exists an inverse correlationship between vibration frequency and amplitude. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122:1778–1784, 2011  相似文献   
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Succinic acid has been pertracted with TOA using free liquid membranes without or with 1‐octanol. The addition of the alcohol led to the increase of up to 2.8–3 times of the acid's initial and final mass flows. At the same time, the influence of 1‐octanol on the transport capacity of the pertraction system was negative, its addition inducing the accumulation of succinic acid into the liquid membrane. A mathematical model describing the acid accumulation inside the liquid membrane has been developed for pertraction systems without and with 1‐octanol and offers good concordance with the experimental data. © 2012 Canadian Society for Chemical Engineering  相似文献   
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EoC 技术是目前基于广电 HFC 网络实现三网融合的最佳接入技术之一,如何来评估及检测 EoC 产品的性能是本文主要解决的问题.本文以主芯片为 SPC -200C 的 HomePLUG BPL 方案 EoC 产品为测试基础,着重阐述了 EoC 产品的全方位性能测试新方法,以便能够为广电运营商提供一种 EoC 产品的测试及检测新手段.  相似文献   
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The distribution of La, Pr, Nd, Eu, Gd and Tb nitrates between water and tributyl phosphate was investigated over a broad range of concentrations. It has been found that the distribution constant varies only slightly with the lanthanide atomic number, whereas the activity coefficients of the salts in concentrated organic solutions change considerably with both the lanthanide atomic number and concentration. Distribution ratios and separation factors for a number of binary mixtures were determined as a function of the composition at constant total concentration in each phase.  相似文献   
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