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science china Chemistry 2004年第3期47卷 251-256页

作者： JIAng Yinzhi1,2.& HU Weixiao1 1. department of pharmaceutical science,{2. of Technology, hangzhou 310032. china 2. department of Applied Chemistry, zhejiang Institute of science and Technology, hangzhou 310033, china 1. department of pharmaceutical science Zhejiang University of Technology 310032 Hangzhou China 2. department of Applied Chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yI)-s-tetrazine (DMpTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group p-1, with a = 0.7133(4) nm, b = 1.1139(2. nm, c = 1.4572.3) nm, α= 102.13(2.°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2. V = 1113.6(7) nm3, μ = 2.12. mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.

Shape blending of artistic brushstroke represented by disk B-spline curves

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progress in Natural science:Materials International 2007年第12期17卷 1501-1507页

作者： Cheng Min1,2.and Wang Guojin1(1. department of Mathematics, zhejiang university,{2., china 2. department of Mathematics, zhejiang university of Technology, hangzhou 310032. china) department of Mathematics Zhejiang University Hangzhou 310027 China 2. department of Mathematics Zhejiang University of Technology Hangzhou 310032 China

This paper presents an algorithm for automatically generating in-between frames of two artistic brushstrokes. The basic idea of the algorithm is to represent the two key frames of artistic brushstrokes in disk B-spline curves, and then make blending of their geometric intrinsic variables. Given two key frames of artistic brushstrokes, the skeleton curves can be obtained by certain skeleton-based techniques. After disk B-spline representation of the key frames is generated, interpolation of the intrinsic variables of the initial and the target disk B-spline curves is carried out. Examples show that this method can efficiently create in-between frames of artistic brushstrokes.

关键词： computer aided calligraphy shape blending brushstroke disk B-spline curve skeleton.

Dynamic behavior of polymer surface and the time dependence of contact angle

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science china Chemistry 2005年第6期48卷 553-559页

作者： WAng Xinping1, CHEN Zhifang1 & SHEN Zhiquan2.1. Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry, department of Applied Chemistry, zhejiang Institute of {2. and Technology, hangzhou 310033, china 2. department of p.lymer.science and engineer.ng, zhejiang university, hangzhou 3.002., china 1. department of Applied Chemistry Zhejiang Institute of Science and Technology Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry 310033 Hangzhou China 2. department of p.lymer.science and engineer.ng Zhejiang University 310027 Hangzhou China

Time-dependent contact angles were measured by depositing sessile drops of wa-ter on the polymer surfaces and monitoring the drop shape as a function of time. It was found that contact angles decreased sharply with contact time and the equilibrium contact angle was finally attained after a certain time. Values of starting (θ s) and equilibrium contact angles (θ e) obtained by the sessile drop method depend on polymer properties. The Wilhelmy plate technique was used to measure advancing and receding contact angles. The variations of starting (θ s) and equilibrium contact angles (θ e), advancing (θ a) and receding contact angles (θ r) have been studied on the oxidized surface of polymers containing polybutadiene block to explore the cause of time-dependence in contact angle measurement and the meaning of θ s and θ e. The results showed the linear relationships between starting (θ s) and advancing contact angles (θ a), the equilibrium (θ e) and receding contact angles (θ r). The similar relationship was also established between the contact angle hysteresis (θ a?θ r) and differences (θ s ?θ e) in starting contact angles and equilibrium contact angles. Therefore, time-dependence in contact angle measurement was mainly attributed to the surface reconstruction when water drops were deposited on polymer surfaces. The starting contact angle was contributed by the hydrophobic component on polymer surface and the equilibrium contact angle mainly by the hydrophilic component of polymer. These results not only demonstrated the interdependency between two contact angle measurements, the sessile drop method and the Wilhelmy plate technique, but also provided the experimental evidence to explain the cause of time-dependent contact angle. This may also provide a new method to study dynamic behavior of polymer surface.

关键词： contact angle, surface dynamic behavior, polymer surface, dynamic contact angle, time-dependence.

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,{2., hangzhou 3.002., zhejiang, china. [a]department of Environmental science Zhejiang University Hangzhou 310028 Zhejiang China

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 （〉 2.（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

Interaction mechanisms of organic contaminants with burned straw ash charcoal

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Journal of Environmental sciences 2010年第10期22卷 1586-1594页

作者： Wenhai Huang,Baoliang Chen department of Environmental science,{2. university,hangzhou 3.002.,china [a] department of Environmental science Zhejiang University Hangzhou 310028 China

Black carbons （e.g., charcoal） have a great impact on the transport of organic contaminants in soil and water because of its strong affinity and ubiquity in the environment. To further elucidate their interaction mechanism, sorption of polar （p-nitrotoluene, m-dinitrobenzene and nitrobenzene） and nonpolar （naphthalene） aromatic contaminants to burned straw ash charcoal under different de-ashed treatments were investigated. The sorption isotherms fitted well with Freundlich equation, and the Freundlich N values were all around 0.31-0.38, being independent of the sorbate properties and sorbent types. After sequential removal of ashes by acid treatments （HCl and HCl-HF）, both adsorption and partition were enhanced due to the enrichment of charcoal component. The separated contribution of adsorption and partition to total sorption were quantified. The effective carbon content in ash charcoal functioned as adsorption sites, partition phases, and hybrid regions with adsorption and partition were conceptualized and calculated. The hybrid regions increased obviously after de-ashed treatment. The linear relationships of Freundlich N values with the charring-temperature of charcoal or biochar （the charred byproduct in biomass pyrolysis） were observed based on the current study and the cited publications which included 15 different temperatures （100-850℃）, 10 kinds of precursors of charcoal/biochar, and 10 organic sorbates.

关键词： ash charcoal organic pollutant adsorption partition effective carbon

Online uniform machine covering with the known largest size

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progress in Natural science:Materials International 2007年第11期17卷 1271-1278页

作者： Cao Shunjuan1,2.and Tan Zhiyi1,3(1. department of Mathematics, zhejiang university,{2., china 2. department of Mathematics, zhejiang Forestry university, hangzhou 311300, china 3. State Key Laboratory of CAD & CG, zhejiang university,{2., china) department of Mathematics Zhejiang University Hangzhou 310027 China department of Mathematics Zhejiang Forestry University Hangzhou 311300 China State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China

This paper investigates the semi-online scheduling problem with the known largest size on two uniform machines. The objective is to maximize the minimum machine completion time. Both lower bounds and algorithms are given. Algorithms are optimal for the majority values of s≥1, where s is the speed ratio of the two machines. The largest gap between the competitive ratio and the lower bound is about 0.064. Moreover, the overall competitive ratio 2.matches the overall lower bound.

关键词： scheduling and covering uniform machine design and analysis of algorithm online competitive ratio

Lipschitz continuity of best approximations and Chebyshev centers

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Chinese science Bulletin 1998年第3期43卷 185-188页

作者： LI Chong 1 and WAng Xinghua 2.1. Center for Mathematical sciences, zhejiang university,{2., china 2. department of Mathematics, hangzhou university,{2., china Center for Mathematical sciences Zhejiang University Hangzhou China department of Mathematics Hangzhou University Hangzhou China

The Lipschitz continuity results are given for best approximations and Chebyshev centers. Consequently, the open problem presented by Septycki and Vleck is solved completely.

关键词： best approximation Chebyshev center uniform convexity.

Effects of Ca substitution and surface treatment on electrochemical performances of Ml_(1.0-x) Ca_xNi_(4.0) Co_(0.6) Al_(0.4) hydrogen storage alloy electrodes

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中国有色金属学会会刊：英文版 1999年第3期9卷 487-492页

作者： Chen Weixiang(陈卫祥) 1, Qi Jianqin(祁建琴) 1, Chen Changpin(陈长聘) 2.1. department of physics 2. department of Materials {2. and engineer.ng, zhejiang university, hangzhou 3.002., p. R. china zhejiang Univ Dept Phys Hangzhou 310027 Peoples R China zhejiang Univ Dept Mat Sci & Engn Hangzhou 310027 Peoples R China

The influences of Ca substitution for Ml and surface treatment on electrochemical performances of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 hydrogen storage alloy electrode were investigated. Ca substitution with x 2.for Ml could improve its discharge capacity, but Ca substitution with x >0.2.could decrease the capacity. It was also found that Ca substitution deteriorates the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. In order to improve these properties of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 alloy electrode, the alloy was treated in 6 mol/L KOH+0.02.mol/L KBH 4 solution. The results showed that the surface treatment improves the electrochemical performances such as the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. :The influences of Ca substitution for Ml and surface treatment on electrochemical performances of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 hydrogen storage alloy electrode were investigated. Ca substitution with x 2.for Ml could improve its discharge capacity, but Ca substitution with x >0.2.could decrease the capacity. It was also found that Ca substitution deteriorates the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode. In order to improve these properties of Ml 1.0- x Ca x Ni 4.0 Co 0.6 Al 0.4 alloy electrode, the alloy was treated in 6 mol/L KOH+0.02.mol/L KBH 4 solution. The results showed that the surface treatment improves the electrochemical performances such as the electrocatalytic activity, high rate dischargeability and cycling durability of the alloy electrode.

关键词： hydrogen storage alloy electrode Ca substitution surface modification

Electro-mechanical response of functionally graded beams with imperfectly integrated surface piezoelectric layers

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science china(physics,Mechanics & Astronomy) 2006年第5期49卷 513-525页

作者： YAN Wei1 & CHEN Weiqiu1,2.1. department of Civil engineer.ng,{2., hangzhou 3.002., china 2. State Key Lab of CAD & CG,{2., hangzhou 3.002., china 1. department of Civil engineer.ng Zhejiang University Hangzhou 310027 China 2. State Key Lab of CAD & CG Zhejiang University Hangzhou 310027 China

The time-dependent behavior of a simply-supported functionally graded beam bonded with piezoelectric sensors and actuators is studied using the state-space method. The creep behavior of bonding adhesives between piezoelectric layers and beam is characterized by a Kelvin-Voigt viscoelastic model, which is practical in a high temperature circumstance. Both the host elastic functionally graded beam and the piezoelectric layers are orthotropic and in a state of plane stress, with the former being inhomogeneous along the thickness direction. A laminate model is employed to approximate the host beam. Moreover, the coupling effect between the elastic deformation and electric field in piezoelectric layers is considered. Results indicate that the viscoelastic property of interfacial adhesives has a significant effect on the function of bonded actuators and sensors with time elapsing.

关键词： functionally graded beam piezoelectric layers Kelvin-Voigt model state-space method

ATp as anindicator of biomass activity in thermophilic upflow anaerobic sludge blanket reactor

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Journal of Environmental sciences 2000年第3期12卷 380-384页

作者： CHEN Hong (department of Environmental science and {2. ,zhejiang university ,hangzhou 31 0 0 2.7,china) 浙江大学浙江杭州 3 1 0 0 2

Thisworkinvestigatedthebiomassactivityinathermophilicupflowanaerobicsludgeblanket (UASB )reactorof wastewatertreatment .SynthetictextilewastewaterwithpH 1 0— 1 1 ,CODlevelof2.0 0 0— 30 0 0mg/Lwastested .Cellularadenosine triphosphate (ATp)involatilesolids (VS ;mgATp/gVS)wasmeasuredandexpressedasspecificATpcontenttocomparethe biomassactivityinupzoneandlowerzoneinUASBreactor .TheresultshowsthatthespecificATpcontentbasedontotalvolatile solids (VS)inlowerzone ( 0 .0 4 6mgATp/gVSaverage)ismuchlowerthanthatinupzone ( 0 .62.gATp/gVSaverage)duetohighcontentofinactivebiomassandhighpHinlowerzone .TheSATpinupzoneincreasesasHRTincreasesandapproachestoa maximumvalueof 0 .85mgATp/gVSatHRTof 7h ,thendecreases .ItshowsmostofthetotalVSinupzonerepresentactive bacterialbiomassatHRTof 7h .Rateofsubtractutiliz*** effectofHRTonSATpinlowerzoneisnotassignificantasonSATpinupzone .ThebuffercapacityofthethermophilicUASB reactorisverygood .ItistheactivityofsludgegranulesinlowerzonethatgivetheUASBreactorsuchagoodbuffercapacitytotheinlethighpH .

关键词： ATp biomassactivity UASBreactor