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981.
聚环硫氯丙烷或环硫氯丙烷与环氧氯丙烷共聚物,在少量二乙烯三胺存在下制得交联预聚物,将交联预聚物与4-氨基安替吡啉(4AAP)或乙基原磺酸钾(PEA)反应,制得四种侧链带氨基安替吡啉,乙基原碘酸基的新型螯合树脂。它们对贵金属具有优良的吸附性能和高的吸附选择性。并通过X-射线光电子能谱初步探讨了树脂对金属离子的螯合作用。 相似文献
982.
The thermal conductivities of several nanofluids (dispersions of alumina nanoparticles in ethylene glycol) were measured at temperatures ranging from 298 to 411 K using a liquid metal transient hot wire apparatus. Our measurements span the widest range of temperatures that have been investigated to date for any nanofluid. A maximum in the thermal conductivity versus temperature behavior was observed at all mass fractions of nanoparticles, closely following the behavior of the base fluid (ethylene glycol). Our results confirm that additional temperature contributions inherent in Brownian motion models are not necessary to describe the temperature dependence of the thermal conductivity of nanofluids. Our results also show that the effect of mass or volume fraction of nanoparticles on the thermal conductivity of nanofluids can be correlated using the Hamilton and Crosser or Yu and Choi models with one adjustable parameter (the shape factor in the Hamilton and Crosser model, or the ordered liquid layer thickness in the Yu and Choi model). 相似文献
983.
Yu. N. Sazanov A. V. Gribanov M. Ya. Goikhman M. K. Abdulakhatov S. A. Bartenev S. A. Strelkov N. G. Firsin V. S. Gusel’nikov 《Russian Journal of Applied Chemistry》2007,80(8):1379-1383
Interaction of ITA-31 polyimide binder with a series of industrial sorbents based on styrene and vinylpyridine derivatives was studied. 相似文献
984.
G. F. Lebedeva T. Ya. Yarkova V. V. Platonov V. A. Proskuryakov 《Russian Journal of Applied Chemistry》2005,78(8):1360-1363
The possibility of chemical modification of peat humic acids in order to increase their bioactivity by reduction with tin(II) chloride and sodium borohydride and also by carboxylation using the Kolbe method was analyzed. 相似文献
985.
A. E. Raevskaya A. L. Stroyuk S. Ya. Kuchmii 《Theoretical and Experimental Chemistry》2005,41(3):181-186
We have shown that CdSe/CdS nanocomposites can be obtained in a photocatalytic reaction with participation of CdS nanoparticles from sodium selenosulfate. We have studied the kinetic characteristics of this process in detail and have shown that its most likely mechanism includes a step involving reaction between SeSO3/2− anions and electrons generated in the conduction band of the CdS nanoparticles during irradiation and stabilized in traps on the semiconductor surface.__________Translated from Teoreticheskaya i Eksperimental’naya Khimiya, Vol. 41, No. 3, pp. 171–175, May–June, 2005. 相似文献
986.
O. Ya. Neiland K. A. Balodis V. Yu. Khodorkovskii V. Zh. Tilika 《Chemistry of Heterocyclic Compounds》1991,27(9):1034-1034
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1278–1279, September, 1991. 相似文献
987.
This review surveys the progress in inorganic liquid-liquid extraction in the last 25 years. Achievements are emphasized in the theoretical foundations of the method, and in the synthesis, characterization and application of new extractants. Special attention is paid to the implementation of extraction methods and to the automation of extractive separation. The combination of liquid-liquid extraction as a method of preconcentration with the methods of subsequent determination of trace concentrations of elements is described in detail. 相似文献
988.
989.
I. V. Turovskii V. T. Glezer L. Ya. Avota Ya. P. Stradyn S. A. Hiller 《Chemistry of Heterocyclic Compounds》1973,9(7):914-916
The protolysis constants of pyridazin-6-one and some of its derivatives have been determined by the spectrophotometric method. The influence of substituents on the value of the protonation constants is discussed.Translated from Khimiya Geterots iklicheskikh Soedinenii, No. 7, pp. 993–995, July, 1973. 相似文献
990.
[formula: see text] The synthesis of all four diastereomers of bis(propionates), 3,5-dialkoxy-2,4-dimethylalkanals, by non-aldol aldol chemistry is described. The epoxy alcohols (3, 4) were converted into the mesylates (9, 11) which were cleanly rearranged to the desired 3,5-bis(oxygenated)-2,4-dimethylalkanals (10, 12) in high yield. The epoxy mesylates (13, 16) gave the desired products (14, 17) in good yield on treatment with TMSOTf and a hindered base. 相似文献