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901.
羧甲基壳聚糖/聚乙烯醇/甘油环氧树脂蛇笼型复合螯合膜的制备及对金属离子的吸附性能 总被引:4,自引:0,他引:4
以交联甘油环氧树脂交联的聚乙烯醇(PVA)为笼树脂,羧甲基壳聚糖(CCTS)为蛇树脂制备了具有蛇笼结构的复合螯合膜,研究了其对Cu^2 、Ni^2 、Pb^2 、Fe^3 、Zn^2 ,Hg”^2 、Cd^2 等金属离子的吸附性能,研究表明,该树脂对Cu^2 、Ni^2 、Pb^2 有较好的吸附性能,其中PVA是对Cu^2 的吸附的主要贡献者,而CCTS则是在对Ni^2 的吸附中起主要作用。该树脂可以用于含Cu^2 废水的处理。 相似文献
902.
Enol and keto tautomers of methyl 3-oxo pentanoate could be separated on a HP-5 capillary column. The chromatographic peaks
were identified by examining characteristic mass ions arose from the corresponding enol and keto molecular ions. The study
showed that the area percentage of enol tautomer is a function of temperature of the column. Treating the column as a reactor,
the energy of activation for the on-column tautomerization could be extracted (35.1 kJ mol−1) by monitoring the loss of the enol tautomer, because the reaction is found to obey pseudo first-order kinetics. The enthalpy
and the entropy changes (ΔH = −3.98 kJ mol−1, ΔS = −7.89 J K−1mol−1) for the enol-to-keto reaction in the stationary phase were also obtained. 相似文献
903.
M. A. Aramendía V. Borau C. Jiménez J. M. Marinas A. Moreno F. J. Urbano 《Reaction Kinetics and Catalysis Letters》1995,56(1):87-96
We have studied the activity of Pd/sepiolite and Pd/SiO2–AlPO4 catalysts in cyclohexane aromatization. The catalysts were characterized by H2 chemisorption measurements. The influence of support and reduction temperature on the metal surface properties and activity of the catalysts is discussed. 相似文献
904.
1- and 2-Methoxy-heptafluorophenazine and 1- and 2-bromoheptafluorophenazine have been obtained by anodic oxidation of appropriately substituted 2-amino-octafluorodiphenylamines, the synthesis of which is described. By reaction of octofluorophenazine with suitable nucleophiles, 2-methoxy-, 2-hydroxy and 2-N,N1-dimethylamino-heptafluorophenazine were formed; some of their reactions are described. 相似文献
905.
D. Umarova S. Kh. Maekh S. Yu. Yunusov P. G. Gorovoi É. V. Boiko 《Chemistry of Natural Compounds》1977,12(6):706-708
Summary The alkaloid composition of four far-eastern species ofThalictrum — Th. amurense, Th. contortum, Th. filamentosum, andTh. minus — have been studied, for the first time in the case of the first three species.Th. amurense contains -allocryptopine and thalictrisine, andTh. contortum contains -allocryptopine. Glaucine and thalicsimidine have been found inTh. filamentosum, and argemonine has been isolated fromTh. minus for the first time.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Pacific Ocean Institute of Bioorganic Chemistry, Far-Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 788–791, November–December, 1976. 相似文献
906.
A. L. Klyachko I. Bankós T. R. Brueva G. I. Kapustin 《Reaction Kinetics and Catalysis Letters》1985,29(2):451-455
The adsorption of NH3 has been studied on N,Na-MOR samples at 573 K by microcalorimetry. The heat of adsorption as a function of coverage shows a stepwise change. The steps can be attributed to different cationic sites characterized by distinct energy of ammonia adsorption. An increase in the degree of ion exchange increases not only the number of acid sites but their strength, too. The calorimetric measurements made possible to determine the number of acid centers of different strengths.
NH3 N,Na-MOR 573 K. . , . , . .相似文献
907.
J. Tichy M. M. Andrushkevich G. K. Boreskov A. A. Davidov L. M. Plyasova V. D. Sokolovskii 《Reaction Kinetics and Catalysis Letters》1976,5(4):407-413
The products of selective oxidation are shown to be formed via a stepwise mechanism with participation of surface allylic complexes. A successive transformation of -allyl to -allyl and further to acrolein is possible. The products of complete oxidation may be formed through surface carbonate-carboxylate complexes via either a stepwise mechanism involving the catalyst's oxygen, or a concerted mechanism with the participation of molecular oxygen.
, . - -, . - , .相似文献
908.
A slight discrepancy appears between the treatment of the steady state of diffusion controlled bimolecular quenching of excited species either by the pair model or by the continuum model. A simplifying assumption is pointed out which helps to solve the steady state case but which is responsible for the discrepancy. The error involved is of small importance considering the experimental accuracy.
- , . , , . , .相似文献
909.
V. A. Tertykh L. A. Belyakova A. M. Varvarin 《Reaction Kinetics and Catalysis Letters》1989,40(1):151-156
Interaction mechanism of (CH3)3SiX silanes (X=Br, I, N3, NCS, NCO, CN, NCNSi(CH3)3 and SO4Si(CH3)3 with dehydrated silica surface has been studied by IR spectroscopy. It has been established that (CH3)3SiCN, (CH3)3SiBr, (CH3)3SiI and [(CH3)3Si]2SO4 can be used as soft silylating agents for endcapping.
(CH3)3SiX (X=Br, I, N3, NCS, NCO, CN, NCNSi(CH3)3, SO4Si(CH3)3) -. , (CH3)3SiCN, (CH3)3SiBr, (CH3)3SiI [(CH3)3Si]2SO4 .相似文献
910.
High-voltage capillary zone electrophoresis of red blood cells 总被引:3,自引:0,他引:3
The high-voltage wide-bore capillary zone electrophoresis of red blood cells was investigated. The reproducibility of the retention time (electrophoretic mobility) is excellent and the differentiation among various species is good. The peaks in the electropherogram describe the distribution of the size and/or surface charge of the cells and are therefore broad. The relationship between the peak height and the number of cells injected is good, with linear correlation coefficients better than 0.98. Details of the preparation of cell suspensions and support electrolytes are given, which is essential for obtaining reproducible results. The inner surface of FEP capillary tubing is degraded by the application of high voltage and a pause is necessary between successive experiments if good and reproducible peak shapes are to be obtained. The length of the pause increases with the number of experiments made, and finally the tubing becomes useless. Inspection of the inner surface by X-ray photoelectron spectroscopy showed the breakdown of CHF bonds, but the actual mechanism is not known. 相似文献