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101.
合成1,3-二(3-羟丙基)四甲基二硅氧烷的新方法   总被引:2,自引:0,他引:2  
用二乙氧基二甲基硅烷与3-氯丙醇反应,合成了新化合物3-氯丙氧基乙氧基二甲基硅烷,然后用格氏反应代替Walter的钠缩合反应,最后经水解制备了1,3-二(3-羟丙基)四甲基二硅氧烷,总收率为42.0%。  相似文献   
102.
A new interfacial polymerization (IP) procedure is developed in order to synthesize polypiperazine-amide thin-film membrane on the inner surface of poly(phthalazinone ether sulfone ketone) (PPESK) hollow fiber ultrafiltration (UF) membrane.A hollow fiber composite membrane with good performance was prepared and studied by FT-IR and scanning electron microscopy.  相似文献   
103.
An ordinary plating solution for indium hexacyanoferrate (InHCF) thin film deposition, mainly composed of equal concentrations of In3+ and [Fe(CN)6]3–, usually forms precipitates rapidly when either concentration is higher than few millimolar. This contributes to the plating solution's instability. Moreover, electrodeposited capacities are limited accordingly. In this work, the plating solution's stability and the electrodeposition of InHCF were greatly enhanced by adding a large amount of K+ and/or H+. It was found that a 10-mM plating solution added with 1 M HCl and 1 M KCl could be stored as fresh over a one-week period, whereas an unmodified plating solution became useless within a couple of minutes. Also, such cationic additions, especially adding H+, increased the electrodeposited capacity ca. 18 times at least, as compared with that obtained from the unmodified plating solution. Furthermore, related enhancing mechanisms were proposed and verified. To sum up, this study offers a means for better InHCF electrodeposition and should promote the applications of InHCF films. Electronic Publication  相似文献   
104.
胍类化合物的合成进展   总被引:5,自引:0,他引:5  
胍类化合物是精氨酸残体的一部分,它在具有生物活性的蛋白质、肽中起着重要作用,从天然产物分离得到的胍类化合物大部分具有生理活性,如抗病毒、抗肿瘤、抗艾滋病等。所以,在温和条件下高产率的合成胍类化合物显得非常重要。本文综述了胍类化合物的合成进展。参考文献32篇。  相似文献   
105.
The reaction pathway towards formation of 4-aroyl-3-hydroxy-2(5H)-furanones 1 from the base catalyzed reaction between an acetophenone, diethyl oxalate and formaldehyde was investigated. If methoxide was used as base, a transesterification was found to occur in the first step, while a side reaction, namely the retro Claisen reaction, was in competition with the desired lactone formation in the second step. The nature of the solvent and the acidic character of 1 as well as the basicity of the aminoarylene were found to have a profound influence on the course of the reaction of 1 with aminoarylenes.  相似文献   
106.
Oxychelerythrine, benzo[c]phenanthridine alkaloid, was synthesized from easily available starting toluamide 5 and benzonitrile 6 using toluamide-benzonitrile cycloaddition reaction in 6 steps.  相似文献   
107.
Multicomponent Na2V6O16.3H2O (barnesite) single-crystalline nanobelts were synthesized by a direct reaction-crystallization growth of bulk V2O5 and NaF powders under hydrothermal treatment without using any templates or catalysts. This new strategy could be extended to prepare other one-dimensional multicomponent nanomaterials including ammonium, alkali-metal or alkali-earth metal vanadium oxide bronzes and other transition metal oxyfluorides. This is an efficient and mild solution method with clear advantages over the traditional high-temperature approach for the large-scale production of 1D multicomponent nanomaterials. The applicability of this approach toward the preparation of other inorganic systems, such as tungstates and molybdates, will be explored.  相似文献   
108.
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110.
The Cu-Mo/ZSM-5 catalysts with different Cu/Mo ratios were prepared by wet impregnation method, and their catalytic performance for selective catalytic reduction of NOx was studied. The results showed that Cu-Mo/ZSM-5 is a very effective catalyst for NOx catalytic reduction with ammonia, especially when Cu/Mo molar ratio is about 1.5. It not only exhibited the extremely high catalytic activity, but also showed good stability for 02. The bulk phase structure of Cu-Mo/ZSM-5 catalysts was determined by XRD technique, and the results indicated that there is a maximum dispersion for Cu species when Cu/Mo molar ratio is 1.5, and an interaction between Cu and Mo along with HZSM-5 may be present in Cu-Mo/ZSM-5, which may possibly result in a special structure favorable for the catalytic reduction of NOx over Cu-Mo/ZSM-5 catalyst.  相似文献   
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