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991.
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含吲哚核端基多甲川菁染料的合成及性能 总被引:6,自引:0,他引:6
我们曾合成了具有桥环的硫三碳菁及多甲川苯乙烯菁,并测定了光学性能。本文报道吲哚环为端基的桥链三碳菁和四甲川苯乙烯菁的合成及在有机溶剂中电子吸收光谱及溶解性能的测定。所用仪器同前,7种多甲川菁染料的合成反应如下: 相似文献
995.
Carbon Nanotubes Grown on Sepiolite as Catalyst Carrier 总被引:2,自引:0,他引:2
Multi-walled carbon nanotubes were synthesized by the catalytic decomposition of acetylene at 750℃ over sepiolite powder,which was treated with aqueous cobalt nitrate. It is expected that the composite with high specific area will have high capacity of hydrogen storage. 相似文献
996.
Visible light induced photocatalytic reaction of rhodamine B dye via 12-tungstosilicic acid in water
Using 12-tungstosilicic acid (SiW124-) as the catalyst, rhodamine B (RhB) dye in an aerated aqueous solution can undergo an effective photocatalytic stepwise N-deethylation process under visible light irradiation, and dioxygen is reduced to hydrogen peroxide by the reducedSiW12 4-. This provides the potential for moving polyoxometalate-based photocatalytic processes from the near-UV into the visible region of the spectrum. 相似文献
997.
Isolation of lipase producer and its performance in enantioselective hydrolysis of glycidyl butyrate
A racemic glycidyl butyrate resolving strain, preliminarily identified as a Rhizopus sp., had been isolated from soil. Its extracellular lipase was found to enantioselectively hydrolyze the (S)-enantiomer of
the chiral ester, with optimal activities at pH 5.3 and 42°C. Higher en antioselectivity of theenzyme was observed at lower
temperatures, while the best anantioselectivity was obtained at pH 5.5–6.0, with an, E value (enantiomeric ratio) of 57. 相似文献
998.
Colloid titration and streaming current detector are two popular techniques used to determine the charge density of dissolved and colloidally dispersed polyelectrolytes. However, both techniques are based on some assumptions that may not be valid under some circumstances. In this paper, a membrane separation technique developed to determine the charge density and characterize a charge neutralization reaction is described. The technique characterizes the reaction between cationic and anionic charge carriers by measuring the counterions released during reaction or the unreacted small molecule charge carriers. Membranes with selected cutoff pore size were used to separate the species of interest from the bulk of the reaction mixture. Three different charge determination techniques were also compared. 相似文献
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1000.
Fandong Meng Genhui Xu Baowei Wang Xinbin Ma. School of Chemical Engineering Technology Tianjin University Tianjin China . Luoyang Petrochemical Engineering Corporation Luoyang ChinaManuscript received March revised Apr 《天然气化学杂志》2002,(Z1)
This article describes a process for the synthesis of diethyl oxalate by a coupling reaction of carbon monoxide, catalyzed by palladium in the presence of ethyl nitrite. The kinetics and mechanism of the coupling and regeneration reaction are also discussed. This paper presents the results of a scale-up test of the catalyst and the process based on an a priori computer simulation. 相似文献