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131.
2,6-二甲基萘生产技术进展 总被引:2,自引:0,他引:2
许杰 《精细石油化工进展》2003,4(2):44-47
概述了国外2,6-二甲基萘生产技术现状,详细介绍了ExxonMobil公司2,6-二甲基萘的工艺路线和日本神户制钢所的提纯方法,指出了实现我国2,6-二甲基萘工业化生产应注意的问题。 相似文献
132.
U(Ⅳ)-U(Ⅵ)同位素交换反应动力学研究 Ⅰ.Fe~(2+)对U(Ⅳ)-U(Ⅵ)同位素交换反应的催化作用 总被引:1,自引:0,他引:1
一、前言由于U(IV)-U(VI)同位素交换体系具有相当大的同位素效应和很好的稳定性,并且容易实现两相回流,这对于分离U同位素的工业应用都是十分有利的。但是,U(IV)-U(VI)同位素交换反应速度非常慢,常温下H~+浓度为1.0—4.0 mol/l时,速度常数为1.0×10~(-4)l~2/mol·s。因此要用U(IV)-U(VI)交换体系浓缩铀同位素,必须研究U(IV)-U(VI)交换反应动力学,找到加快交换反应的方法。 相似文献
133.
Gas-phase selective oxidation of toluene has been carried out on vanadium oxide systems (5–20 wt.% of V2O5, equivalent to 0.4–1.7 theoretical monolayers) supported on TiO2–sepiolite (with titania loading around the theoretical monolayer, 12 wt.%) and on sepiolite. A study has been made on both the influence of vanadia loading and of the support on the catalytic behaviour of the supported vanadium systems. The reducibility by H2 TPR was also studied as well as the acid and basic/redox sites from the results of conversion of the 2-propanol test reaction of the solids. Benzaldehyde, benzoic acid and several coupling products were the main ones detected, attaining over 50% selectivity towards the benzaldehyde and benzoic acid products at a total conversion around 10%. The activity and selectivity to the selective products exhibited by vanadium systems supported on mixed support were superior to those exhibited by the systems supported on sepiolite and increased notably in both series with the increase in vanadium loading. The best catalytic behaviour exhibited by the vanadium systems supported on mixed support, which also exhibited the highest density of sites capable of being reduced (as well as their reducibility) and of those responsible for propanone formation, could be attributed not only to the different balance of the vanadia species existing in the two supports (monomeric + oligomeric/polymeric), but also to such other factors as the nature of the support and, concretely, its chemical composition. 相似文献
134.
A novel one-shell high temperature and high pressure semi-continuous reactor has been developed for the study of the Boudouard reaction at temperatures up to 820 °C and pressures up to 32.5 MPa. Semicontinuous gasification of charcoal using supercritical CO2 has been achieved at conversions up to 90.8% (w/w) at LSHV between 20 and 30 h−1 after 5–9 h. A gasification model is proposed and validated. Effective rates of gasification (1.32 ± 0.12) × 10−6 to (6.10 ± 2.03) × 10−5 s−1 were obtained. The results indicated that this method is technically feasible for the on-line production of high pressures streams of CO/CO2 in the lab for carrying out further chemistries, avoiding the use of CO high pressure bottles. 相似文献
135.
Nanocrystalline thin films of important surface roughness and complexity were prepared by screen-printing of commercial TiO2 powder. The screen-printed titania films were tested in the photocatalytic decomposition reaction of methyl orange under UV light (350 nm). The photocatalytic activity strongly depends on the titania paste components and especially on the presence of a surface modifier (acetyl acetone) combined with a rheology controlling agent (ethyl cellulose). This results in improvement of the paste viscosity and optimization of the films morphology. Experiments under direct full sunlight illumination prove the importance of the screen-printed films for practical applications. 相似文献
136.
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138.
Ed W.B de Leer 《Water research》1985,19(11):1411-1419
In harbour sediment samples taken near an epichlorohydrin production plant, a series of highly chlorinated ethers and diethers were detected viz. three isomeric bis(dichloropropyl)ethers, several structurally closely related ethers with 9 carbon atoms (C9 ethers), a number of C12 ethers and diethers, and finally several C15 ethers. The formation of this new class of ether compounds can be explained on the basis of the chemistry of the addition of HOCl to allylchloride. After initial addition of Cl−, a reactive intermediate is formed which may react with the product dichloropropanol, to give the C6 ethers, or may polymerize with the starting compound allylchloride followed by reaction with the product, to give the C9, C12 and C15 ethers. 相似文献
139.
本文将2,3-酸在甲苯溶剂中用氯化亚砜酰氯化合成2-羟基萘-3-甲酰氯,将其分别和正丁胺、正辛胺、正十二胺和正十八胺反应制得4种不同碳链长度的2-羟基萘-3-甲酰烷基胺,用对硝基苯胺重氮盐与其偶合分别制得了对硝基苯偶氮2-羟基萘-3-甲酰正丁胺、对硝基苯偶氮2-羟基萘-3-甲酰正辛胺、对硝基苯偶氮2-羟基萘-3-甲酰正十二胺和对硝基苯偶氮2-羟基萘-3-甲酰正十八胺系聚丙烯纤维用红色染料。熔点分别为189.8℃、96.2℃、115.8℃和108.1℃;热分解点分别为273.1℃、216.0℃、258.0℃和221.0℃;最大吸收波长分别为515.8nm、516.8nm、513.6nm和514.2nm。在染色条件下,4支染料在聚丙烯纤维上的上染率分别37.6%、41.8%、42.4%和44.7%。 相似文献
140.