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971.
972.
采用高温固相法合成了一种长波紫外激发的SrZnO2∶Eu3+,Li+发光材料,用X射线衍射谱、荧光光谱对样品进行了表征。结果表明,Eu3+离子在SrZnO2基质中主要占据Sr2+离子不对称性格位,发射来源于5D0→7F2612 nm为主的红光。加入电荷补偿剂Li+离子能显著提高发光强度,350~400 nm内的激发峰也有明显提高,同时观察到来自Eu3+离子高能级5D1→7FJ(J=0~2)的跃迁发射,并对其产生机制进行了初步探讨。实验结果表明,SrZnO2∶Eu3+,Li+是一种有发展前途的长波紫外激发红光荧光体。 相似文献
973.
A. V. Kashevskii M. A. Mamalyga T. L. Petrova A. Yu. Safronov V. N. Kizhnyaev 《Russian Journal of Applied Chemistry》2007,80(2):316-321
Copolymers of 1-vinyl-1,2,4-triazole and 5-vinyltetrazole with 1,1,5-trihydrooctafluoropentyl methacrylate and 1,1,7-trihydrododecafluoroheptyl methacrylate were prepared under the conditions of radical initiation. These copolymers were used for modification of the surface of a glassy carbon electrode, and the effect of the modification on the electrochemical behavior of the electrode in anodic oxidation of dopamine and NO was studied. The possibility of enhancing the selectivity of the electrochemical sensor for monitoring NO in biological media was demonstrated. 相似文献
974.
含二氧杂环异黄酮的合成 总被引:8,自引:0,他引:8
本文报道含有3', 4'-亚甲二氧基, 3', 4'-亚乙二氧基, 3, 4'-三亚甲二氧基的异黄酮类化合物的合成, 所得25个新化合物的结构经元素分析、^1H NMR谱确证; 紫外光谱表明有异黄酮特征吸收。文中并对反应机理进行了探讨。 相似文献
975.
Mian Chang Jiayou Yu Shaojun Wang Liping Yang Yi Yang Shihao Cai Shouheng Shi Yan Wang P. W. Zhu 《中国科学B辑(英文版)》1997,40(5):529-534
A synthetical equation is proposed to characterize the essential features of the inverse “S” type curve on the basis of summing-up
simulation approach of “S” type curve. The two physical variables in the model obtained are discussed and the detailed method
used to determine the parameters is given. The model is then presented to describe the crystallization of poly(caryleher ether
ketone) (PEEK) and thermal decomposition of poly(amide-imide) (PAI) respectively. It is found that some thermal characteristic
parameters can be well estimated from the model simu-lated in computer. 相似文献
976.
N. S. Shaglaeva O. V. Lebedeva Yu. N. Pozhidaev R. G. Sultangareev S. S. Bochkareva L. A. Es’kova 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(3):335-338
Hybrid organoinorganic composites insoluble in water and organic solvents were prepared by the hydrolysis of tetraethoxysilane in the presence of poly-1-vinylpyrazole, poly-1-vinylimidazole, and poly-4-vinylpyridine. The composition of the composites was determined by the nature of the polymeric nitrogen base and hydrolysis conditions. The composites synthesized showed high sorption activity in the extraction of the [PdCl4]2?, [PtCl6]2?, and [AuCl4]? ions from hydrochloric acid solutions. 相似文献
977.
I. B. Rozentsveig Yu. A. Aizina K. A. Chernyshev L. V. Klyba E. R. Zhanchipova E. N. Sukhomazova L. B. Krivdin G. G. Levkovskaya 《Russian Journal of General Chemistry》2007,77(5):926-931
The mixtures of mono-and dihalothiophenesulfonyl chlorides, formed in the sulfochlorination reaction of 2,5-dichlorothiophene
and 2,5-dibromothiophene, were treated with aqueous ammonia and thus converted into mixtures of the corresponding stable thiophenesulfonamides.
The structure and composition of the latter were studied by physicochemical methods: GC-MS and 1H, 13C, 1H-13C HSQC, 1H-13C HMBC, and NOESY NMR spectroscopy. As a result of the above chemical transformations, 2,5-dichlorothiophene afforded a mixture
of 5-chlorothiophene-2-sulfonamide and 4,5-dichlorothiophene-3-sulfonamide in a roughly 70:30 ratio. In the case of 2,5-dibromothiophene,
a mixture of 5-bromothiophene-2-sulfonamide, 4,5-dibromothiophene-3-sulfonamide, and 3,5-dibromothiophene-2-sulfonamide (3:54:43)
was formed.
Original Russian Text I.B. Rozentsveig, Yu.A. Aizina, K.A. Chernyshev, L.V. Klyba, E.R. Zhanchipova, E.N. Sukhomazova, L.B.
Krivdin, G.G. Levkovskaya, 2007, published in Zhurnal Obshchei Khimii, 2007, Vol. 77, No. 5, pp. 831–836. 相似文献
978.
979.
Devyatkina T. I. Gun'ko Yu. L. Mikhalenko M. G. 《Russian Journal of Applied Chemistry》2001,74(7):1122-1125
The influence exerted by addition of -hydroxynaphthoic acid and combined additive Hg + Pb + -hydroxynaphthoic acid on the corrosion and self-discharge of a porous zinc electrode in alkali solution was studied. 相似文献
980.