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Chinese Journal of Chemistry 1996年第6期14卷 497-505页

作者： JIANG, Xuan-ZhenDepartment of Chemistry, zhejiang university, Hangzhou, zhejiang 310027, China Department of Chemistry Zhejiang University Hangzhou Zhejiang 310027 China

In situ infrared spectra of dimethyl ether adsorbed on two H-ZSM-5 zeolites are reported which are different in both lattice and extraframework aluminium contents. A number of dissociatively adsorbed dimethyl ether species associated respectively with the Bronsted acid sites, the external silanol groups and extraframework aluminium species at different temperatures are identified. In particular, dimethyl ether reacts with non acidic hydroxyl species associated with extraframework aluminium to form the third methoxy species. The distributions of hydrocarbons desorbed from a single pulse of dimethyl ether (1.0 mL) onto these zeolite samples are presented. Propene is the major product, and the yield of hydrocarbons correlates with the concentration of Bronsted acid bound methoxy groups.

关键词： In situ FTIR dimethyl ether adsorption extraframework aluminium bound methoxy species hydrocarbon products

Effect of background electrolytes on the adsorption of nitroaromatic compounds onto bentonite

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Journal of Environmental Sciences 2009年第8期21卷 1044-1052页

作者： CHEN Baoliang, HUANG Wenhai Department of Environmental Science, zhejiang university, Hangzhou 310028, zhejiang, China. Department of Environmental Science Zhejiang University

To further elucidate interaction of nitroaromatic compounds with mineral surface, the sorption of m-dinitrobenzene （m-DNB） and nitrobenzene to original bentonite in aqueous solution containing different electrolytes （i.e., KCl, NH4Cl, CaCl2 and Tetramethylammonium bromide （TMAB）） was studied. The sorption of m-DNB was greatly enhanced with the presence of KCl and NH4Cl, while little influence was observed with CaCl2 and TMAB, following the order of KCl 〉 NH4Cl 〉〉 TMAB, CaCl2, or DI water. For nitrobenzene, sorption enhancement only occurred at high nitrobenzene concentrations in the presence of KCl, and the solute equilibrium concentration at inflexion point was lowered with increasing KCl concentration. These sorption enhancements were significantly promoted with the increase of electrolyte concentration. The salting-out effect is insufficient to account for the sorption enhancement by original bentonite with increasing KCI or NH4Cl concentration. X-ray diffraction patterns of bentonite suspensions indicated that the sorption enhancement of m-DNB was attributed to the intercalation of K^＋ or NH4^＋ into bentonite interlayer and then dehydration with m-DNB to form inner-sphere complexes, which caused previously expanded bentonite interlayers to collapse in aqueous suspension, thus further enhanced the interaction of phenyl with siloxane surface. In comparison, the sorption enhancement of NB is attributed to the formation of outer-sphere complexes with K^＋ at high solute-loadings （〉 20（0-400 mg/kg）. The sorption of m-DNB to initially modified TMA^＋-bentonite and K^＋-bentonite was almost the same as respective sorption to original bentonite in solution containing TMA^＋ and K^＋.

关键词： sorption nitroaromatic compound bentonite cation type wastewater treatment

Preparation and characterization of bis(dimolybdo-nonatungstogermanate)lanthanates of potassium

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Rare Metals 2003年第1期22卷 6-9页

作者： WU QingyinDepartment of Chemistry, zhejiang university, Hangzhou 310027, China Department of Chemistry Zhejiang University Hangzhou 310027 China

The heteropoly complexes K_(13)[Ln(GeW_9Mo_2O_(39))_2] centre dot nH_2O (Ln =La, Ce, Pr, Nd, and Sm) were prepared for the first time and characterized by chemical analysis,infrared (IR) spectrum, ultraviolet (UV) spectrum, X-ray powder diffraction, and thermal ***, UV spectra, and X-ray powder diffraction studies show that the structure of the heteropolycomplexes is a square antiprism consisting of eight oxygen atoms of two GeW_9Mo_2O_(39)^(8-)heteropolyanions and a lanthanide ion. The thermostability of heteropoly complexes is lower thanthat of saturated Keggin structure dodecatungstogermanate.

关键词： inorganic chemistry heteropoly complex chemical synthesis lanthanates germanium

Corrosion of titanium in supercritical water oxidation environments

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中国有色金属学会会刊：英文版 2002年第6期12卷 1054-1057页

作者：卢建树毛志远张九渊College of Chemical Engineering zhejiang university of Technology 马淳安College of Chemical Engineering zhejiang university of Technology 毛信表College of Chemical Engineering zhejiang university of Technology 李肖华College of Chemical Engineering zhejiang university of Technology College of Chemical Engineering Zhejiang University of Technology College of Materials and Chemical Engineering Zhejiang University

Supercritical water oxidation (SCWO) can effectively destroy many kinds of civilian and military wastes. The high temperature and high pressure SCWO operation conditions generate very corrosive environment that many engineering materials fail to withstand. Preliminary test shows that titanium may be a promising material in most of SCWO conditions. Commercially pure titanium is tested in four kinds of SCWO environments. Phenol, sodium dodecyl benzosulfonate, n amine phenol, and chlorpyrifos were chosen as typical target pollutants. The results show that titanium is only superficially attacked in the first three SCWO environments while in chlorpyrifos SCWO medium titanium is corroded. The corrosion is temperature dependent, with heavier corrosion occurring at near critical temperature. X ray diffraction analysis shows that the corrosion products consist of titanium oxy phosphates and titanium oxide, in which Ti 5O 4(PO 4) 4 is the main phase.

关键词：钛腐蚀超临界水氧化

Strong near-epoch dependence

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Science China Mathematics 2004年第4期47卷 497-507页

作者： LIN ZhengyanDepartment of Mathematics, zhejiang university, Hangzhou 310028, China Department of Mathematics Zhejiang University Hangzhou China

We introduce a new class of dependent sequences of random variables, which is a subclass of near-epoch dependent sequences, but can also be approximated by mixing sequences. For this kind of sequences of random variables, we call them strong nearepoch dependent sequences, a p-order, p ＞ 2, (maximum) moment inequality is established under weaker dependence sizes.

关键词： near-epoch dependence, mixingale, strong near-epoch dependence, moment inequality, convergence.

THE CONVERGENCE ON A FAMILY OF ITERATIONS WITH CUBIC ORDER

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Journal of Computational Mathematics 2001年第5期19卷 467-474页

作者： Dan-fu Han (Department of Mathematics, zhejiang university, Hangzhou 310028, China) 浙江大学浙江杭州 310028

Establishes a convergent theorem for a family of iterations with cubic order by using general convergence hypotheses. Disadvantage of using the cubic majorizing function; Convergence of the majorizing sequence; Overvi... 详细信息

关键词： convergence majorizing method gamma-condition error estimate

Strong uniqueness of best approximations in spaces of bounded linear operators

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Science China Mathematics 2004年第3期47卷 339-351页

作者： LI Chong HE Jinsu Department of Mathematics, zhejiang university Hangzhou 310027, China Department of Mathematics, zhejiang Normal university Jinhua 321004, China Department of Mathematics Zhejiang University Hangzhou China Department of Mathematics Zhejiang Normal University Jinhua China

The present paper is concerned with problems of the strong uniqueness of the best approximation and the characterization of a uniqueness element in operator *** results on the strong uniqueness of the best approximation operatorfrom RS-sets are proved and the uniqueness element of a sun in the compactoperator space from c0 to c0 is characterized by the strict Kolmogorov's *** recent results due to Lewicki and others are extended and improved.

关键词： best approximation operator, RS-set, sun, strong uniqueness, uniqueness element.

ON MULTIPLE POSITIVE SOLUTIONS FOR A NONLINEAR ELLIPTIC PROBLEM IN R^N

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Chinese Annals of Mathematics,Series B 2000年第3期21卷 351-358页

作者： YANG HAITAO(Department of Mathematics, zhejiang university, HangZhou 310027, China.) WU SHAOPING(Department of Mathematics, zhejiang university, HangZhou 310027, China.) Department of Mathematics Zhejiang University Hangzhou 310027 China

By making use of Variational method, the authors obtain some results about existence of multiple positive solutions and their asymptotic behavior as the parameter →＋∞ for a semilinear elliptic problem in RN.

关键词： Critical point Asymptotic behavior Concentration

THE CONVERGENCE OF DURAND-KERNER METHOD FOR SIMULTANEOUSLY FINDING ALL ZEROS OF THE POLYNOMIAL

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Journal of Computational Mathematics 2000年第6期18卷 567-570页

作者： Dan-fu Han (Department of Mathematics, zhejiang university, Hangzhou 310028, China) 浙江大学浙江杭州 310028

In this paper we propose the two kinds of different criterions and use them to judge the convergence of Durand-Kerner method and to compare the obtained results with other methods. [ABSTRACT FROM AUTHOR]

关键词： Durand-Kerner method convergence two kinds of criterions