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981.
壳聚糖硫酸盐催化合成苯甲酸甲酯 总被引:9,自引:0,他引:9
以壳聚糖硫酸盐为催化剂,由苯甲酸和甲醇合成苯甲酸甲酯。考察了催化剂用量、反应时间及醇酸摩尔比等因素对反应的影响,实验结果表明,在催化剂用量为1.0g,反应时间4h,醇酸摩尔比为5:1的条件下,产品收率达90.56%,并且催化剂可重复使用多次。 相似文献
982.
丁洪生 《石油化工高等学校学报》1998,11(2):15-17
采用电化学方法成功地合成了钌掺杂聚吡咯络合物(PPRUC),PPRUC是一种很稳定的非晶态络合物,合成掺杂聚吡咯络合物来改变催化剂的存在形态,使催化剂与反应物和产物很好地分离。用物理吸附仪对PPRUC进行了比表面积和孔容等的测定,用红外和电子能谱对PPRUC进行了表征,用元素分析仪测定了PPRUC含C、N、H的比。根据测定结果和文献报道推断了PPRUC的基本结构。 相似文献
983.
984.
对氨基苯酚合成工艺的改进 总被引:2,自引:0,他引:2
介绍了对氨基苯酚的一种合成工艺 ,探讨了反应条件对产品收率的影响 ,初步得出了适宜的工艺条件。本法具有综合成本较低、操作方便、设备简单等优点 相似文献
985.
986.
The influence of the quantity of urea on the synthesis of calcium aluminate by solution combustion method was studied. It was shown that the amount of urea has a big influence on morphological characteristic and phase composition of the combustion products.The sintering behavior of the combustion products, before and after milling, was studied by rate controlled sintering method, based on which a thermal schedule was designed improving the sintering of CaAl2O4. 相似文献
987.
Jesús Manuel García-Vargas José Luís ValverdeAntonio de Lucas-Consuegra Beatriz Gómez-MonederoFernando Dorado Paula Sánchez 《International Journal of Hydrogen Energy》2013
Tri-reforming of methane has proved to be a highly efficient process for obtaining synthesis gas suitable for use in the Fischer–Tropsch process and methanol synthesis. In this paper the influence of the feedstock composition on methane conversion, the H2/CO molar ratio of the synthesis gas obtained by tri-reforming of methane and the heat released or supplied to the system with a Ni/β-SiC catalyst are all described. Firstly, a factorial plus central composite design of experiments was chosen in order to optimize the independent variables selected. Then, using the experimental data obtained, a quadratic model was built. It was observed that the effect of both water and oxygen volume flow on the H2/CO molar ratio was positive while that of methane and carbon dioxide volume flow was negative. Finally, in order to obtain an energetic optimum inside the target region, the influence of the independent variables studied previously on the overall reaction heat was calculated. 相似文献
988.
Minoru Takekawa Yasuto Fujimaki Shigeru Ohshima Shoji Fujisawa 《Polycyclic Aromatic Compounds》2013,33(3-4):259-266
Chloro-7 H -benz[ de ]anthr-7-ones (chlorobenzanthrones) are useful as starting materials for synthesis of larger polycyclic aromatic compounds by means of condensation. In the synthesis, the position of the chlorine atom is very important because the structure of condensation products strongly depends on it. For this reason, we have synthesized several chlorobenzanthrones. Although 3- and 4-chlorobenzanthrone were prepared by direct chlorination of benzanthrone and by glycerol condensation of 2-chloroanthraquinone, respectively, the synthesis of 1- and 2-chlorobenzanthrone has not yet been successful. In the present study, we attempted to synthesize them by use of the Sandmeyer reaction. First, we nitrated benzanthrone with nitric acid; 1- and 2-nitrobenzanthrone were obtained by nitration in nitrobenzene at 50-60° and in glacial acetic acid at 105-110°, respectively. Then the nitroderivatives were reduced to corresponding aminoderivatives; the reduction was performed with sodium sulfide for 1-nitrobenzanthrone and with hydrogen chloride and tin for 2-nitrobenzanthrone. Finally, chlorination was carried out by use of the Sandmeyer reaction. The products were separated and purified by column-chromatography. The position of chlorination was confirmed by NMR spectroscopy. 相似文献
989.
结合光机结构的设计与制造,提出了C4P综合体系,对其基本组成部分做了论述,并给出一个实例的软硬件构成。最后简略叙述了C4P综合设计与制造体系的实现策略。 相似文献
990.