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Dromion Solutions for Dispersive Long-wave Equations in Two Space Dimensions

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Communications in Nonlinear Science and Numerical Simulation 1997年第4期2卷 225-229页

作者： Yanjuan ZHU (Department of Mathematics &Physics,Guangdong university of technology,Guangzhou 5 1 0 0 90 ,China) Jiefang ZHANG (Research Center of Engineering Science,zhejiang university of technology,Hangzhou 31 0 0 32 ,China Institute of Nonlinear Department of Mathematics and Physics Guangdong University of Technology Guangzhou 510090 China Research Center of Engineering Science Zhejiang University of Technology Hangzhou 310032 China Institute of Nonlinear Physics / Department of Physics Zhejiang Normal University Jinhua 321004 Zhejiang China

By using the homogeneous balance method,we show that the dromion solutions exist for the (2 + 1 ) - dimensional dispersive long- wave *** conjectured thatthe method used here can be generalized to a class of nonlinear... 详细信息

关键词： dromiom solution soliton solution dispersive long- wave eqaution.

CRYSTAL STRUCTURE AND ELECTROCHEMICAL PROPERTIES OF Zr(Mn_(1-x)Ni_x)_2(0.40≤x≤0.75) HYDROGEN STORAGE ALLOYS

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Acta Metallurgica Sinica(English Letters) 2001年第1期14卷 56-62页

作者： W.K. Zhang, C.A. Ma, X.G. Yang, H. Huang, Y.Q. Lei and Q.D. Wang (Department of Applied Chemistry, zhejiang university of technology, Hangzhou 310014, China Department of Materials Science and Engineering, zhejiang university, Hangzhou 310027, China) Dept. of Appl. Chem. Zhejiang Univ. of Technol. Hangzhou 310014 China

The crystal structure, phase abundance and the electrochemical properties of Zr(Mn1-x Nix)2 (0.40 ≤x≤0.75) alloys were investigated by means of XRD, Rietveld refinement method and electrochemical measurements. The alloys are multiphase. C15 Laves phase occurs as a main phase accompanying with C14 phase and other minor phases, indicating that Ni element is C15-stabilized element for ZrMn2 alloy. The phase abundance and lattice parameters of Laves phase are influenced significantly by Ni substitution. The Zr(Mn0.45 Ni0.55)2 alloy with the highest amount of C15 phase exhibits the maximum electrochemical capacity of 242m Ah/g. C14 phase occurring in Zr-Mn-Ni alloys is beneficial for the electrochemical kinetics of hydride electrodes.

关键词： hydrogen storage alloy crystal structure phase abundance,elec- trochemical property

Cytotoxicity of lambda-cyhalothrin on the macrophage cell line RAW 264.7

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Journal of Environmental Sciences 2010年第3期22卷 428-432页

作者： Quan Zhang, Cui Wang, Liwei Sun, Ling Li, Meirong Zhao Research Center of Environmental Science, College of Biological and Environmental Engineering, zhejiang university of technology, Hangzhou 310032, China. [a] Research Center of Environmental Science College of Biological Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China

The wide use and wide-spectrum toxicity of synthetic pyrethroids （SPs） insecticides make them an emerging ecotoxicological concern. Some previous studies showed that SPs possessed cytotoxicity in some immune cells such as human lymphocytes and rat bone marrow. However, the cytotoxicity of SPs to macrophages, which are crucial to innate immunity, has not been explored. In the present report, we investigated a new pyrethroid insecticide, lambda-cyhalothrin （LCT）, which may increase the generation of reactive oxygen species （ROS） and DNA damage levels and cause cytotoxicity in RAW 264.7 cells in dose- and time-dependent manners. The results for the first time implicated increased endogenous ROS and DNA damage as co-mediators of LCT-induced cytotoxicity in macrophages. Our results also suggested that macrophages were involved in synthetic pyrethroid-induced adverse immune effects. Considering the ubiquitous environmental presence of SPs, this study provided new information relative to the potential long-term physiological and immunological effects associated with chronic exposure to SPs. Hence, the potential immunotoxicity of SPs should be considered in assessing the safety of these compounds in sensitive environmental compartments.

关键词： lambda-cyhalothrin macrophage reactive oxygen species cytotoxicity

Understanding the endocrine disruption of chiral pesticides:The enantioselectivity in estrogenic activity of synthetic pyrethroids

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Science China Chemistry 2010年第5期53卷 1003-1009页

作者： WANG Cui 1,ZHANG Quan 1,ZHANG XiaoFeng 1,LIU Jing 2 & LIU WeiPing 2 1College of Biological and Environmental Engineering,zhejiang university of technology,Hangzhou 310032,China 2Key Laboratory of Environmental Remediation and Ecosystem Health,Ministry of Education College of Environmental and Resource Sciences,zhejiang university,Hangzhou 310029,China 1. College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China2. Key Laboratory of Environmental Remediation and Ecosystem Health Ministry of Education College of Environmental and Resource Sciences Zhejiang University Hangzhou 310029 China

Synthetic pyrethroids(SPs) ,a family of chiral insecticides consisting of multiple stereoismers,have been regarded as estrogenic endocrine-disrupting chemicals(EDCs) .In this study,we applied the yeast two-hybrid and molecular docking(MD) assay to assess the enantioselective estrogenic activities of three commonly used SPs,bifenthrin(cis-BF) ,permethrin(PM) and fenvalerate(Fen) .The β-galactosidase analyses indicated that all of the testing pyrethroids displayed significant(p<0.05) *** results showed that the estrogenic potential of cis-BF was mainly attributed to *** PM nor Fen showed estrogenic ***,two stereoisomers of PM possessed estrogenic potential activities.αR-2R-Fen and αS-2S-Fen also induced the β-galactosidase *** inability to initiate the reporter gene expression by the racemic chemicals may be due to the low ratios of these isomers or the antagonism among *** strong hydrophobic interaction and the hydrogen bond between positive estrogenic isomers and ERα support our biological testing *** research demonstrated that the enantioselective estrogenic activity of chiral SPs was due to selective binding between their isomers and the ERα*** data suggests that enantioselectivity of these chiral pesticides is significant to their estrogenic activities.

关键词： enantioselectivity synthetic pyrethroids (SPs) endocrine disruption yeast molecular docking

Enantioselective separation and zebrafish embryo toxicity of insecticide beta-cypermethrin

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Journal of Environmental Sciences 2010年第5期22卷 738-743页

作者： Chao Xu,Wenqing Tu,Chun Lou,Yingying Hong,Meirong Zhao Research Center of Environmental Science,College of Biological and Environmental Engineering,zhejiang university of technology,Hangzhou 310032,China. [a] Research Center of Environmental Science College of Biological Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China

Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between *** this study,enantiomers of insecticide beta-cypermethrin （beta-CP） were separated on selected chiral column by HPLC,and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval *** enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism （CD） at 236 *** separation could be achieved at lower temperature （e.g.,20°C） and with lower levels of polar *** enantiomers were obtained on Chiralcel *** CD spectra of enantiomers were *** comparing the elution order with a previous similar study,the absolute configuration of beta-CP enantiomers was *** individual enantiomers were used in zebrafish embryo test,and the results showed that beta-CP enantioselectively induced yolk sac edema,pericardial edema and crooked *** 1R-cis-αS and 1R-trans-αS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L,while the 1S-cis-αR and 1S-trans-αR induced no malformations at higher concentration （e.g.,0.3 mg/L）.The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects.

关键词： beta-cypermethrin enantioselectivity zebrafish embryo chiral separation

Preparation and Recipe Optimization of Water-based Architectural Heat Insulation Coatings

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Journal of Wuhan university of technology(Materials Science) 2008年第6期23卷 932-937页

作者：陈立军 School of Chemical Engineering and Materials Science Zhejiang University of Technology State Key Laboratory Breeding Base of Green Chemistry-Synthesis technology Zhejiang University of Technology

Water-based architectural heat insulation coatings were studied to overcome the drawbacks of conventional inorganic silicate heat insulation coatings. The heat insulation coatings were prepared with the method of mechanical agitation when the mixed organic polymer emulsions were used as binder of the coatings and the mixed heat insulating aggregates were applied as powder, and some assistants were also added. Water temperature difference in the plastic container, which was coated with heat insulation coatings, represented the heat-insulating property of the coatings. The influences of components of mixed polymer emulsion, mass ratio of polymer emulsion to powder, particle size of heat insulating aggregates, added amount of air entraining admixture and the match of thickeners on the properties of the coatings were studied. The experimental results show that the heat insulation coatings with good finishing, heat-insulation property and artificial weathering can be prepared when the binder is composed of 66.92% styrene-acrylic emulsion, 16.59% elastic emulsion and 16.49% silicone-acrylic emulsion, the mass ratio of polymer emulsion to powder is 0.45, the particle size of heat insulating aggregates is in the rang of 200 and 250 mesh size, the added amount of sericite is 15%, and the added amount of air entraining admixture is in the range of 1.0% and 1.5% and the thickeners are the mixtures of ASE-60 and RM-5000.

关键词： heat insulation coating polymer emulsion heat insulating aggregate preparation recipe optimization

User-controllable mesh segmentation using shape harmonic signature

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Progress in Natural Science:Materials International 2009年第4期19卷 471-478页

作者： Yongwei Miao a,b, Jieqing Fenga, Jinrong Wanga,c, Xiaogang Jin a a State Key Laboratory of CAD & CG, zhejiang university, Hangzhou 310027, China b College of Science, zhejiang university of technology, Hangzhou 310032, China c Information Science & Engineering School, Hangzhou Normal university, Hangzhou 310036, China [a]State Key Laboratory of CAD & CG Zhejiang University Hangzhou 310027 China [b]College of Science Zhejiang University of Technology Hangzhou 310032 China [c]Information Science & Engineering School Hangzhou Normal University Hangzhou 310036 China

Due to different shape modeling applications, partitioning a given complex 3D mesh model into some patches or meaningful subparts is one of the fundamental problems in digital geometry processing. By using the high-dimensional mean-shift clustering scheme in shape signature space, a new method is proposed which can generate user-specified segmentation results automatically for different applications. The shape signature is composed of mesh geometric attributes and its spectral harmonics. The latter one can reflect mesh frequency spectrum information. The low frequency components are essential for semantics-oriented segmentation, while the high frequency components are important for purely geometry-oriented segmentation. The effects of the proposed method are demonstrated by several examples.

关键词： Mesh segmentation Manifold harmonic analysis Shape harmonic signature Mean-shift clustering

Perturbations of the Yang-Mills field in the universe

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Research in Astronomy and Astrophysics 2009年第8期9卷 874-882页

作者： Wen Zhao1,2 1 Department of Physics, zhejiang university of technology, Hangzhou 310014, China W 2 School of Physics and Astronomy, Cardiff university, Cardiff, CF24 3AA, United Kingdom Department of Physics Zhejiang University of Technology Hangzhou 310014 China School of Physics and Astronomy Cardiff University Cardiff CF24 3AA United Kingdom

It has been suggested that the Yang-Mills （YM） field can be a kind of candidate for the inflationary field at high energy scales or dark energy at very low energy scales, which can naturally give the equation of state - 1 〈 ω 〈 0 or ω 〈 - 1. We discuss the zero order and first order Einstein equations and YM field kinetic energy equations of the free YM field models. From the zero order equations, we find that w ＋ 1 ω α^-2, from which it follows that the equation of state of the YM field always goes to - 1, independent of the initial conditions. By solving the first order Einstein equations and the YM field equations, we find that in the YM field inflationary models, the scale-invariant primordial perturbation power spectrum cannot be generated. Therefore, only using this kind of YM field is not enough to account for inflationary sources. However, as a kind of candidate for dark energy, the YM field has the ＇sound speed＇ c^28 = -1/3 〈 0, which makes the perturbation Ф have a damping behavior at large scales. This provides a way to distinguish the YM field dark energy models from other kinds of models.

关键词： cosmology theory- gravitation- methods analytical

Interactive point cloud blending by drag-and-drop

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Journal of zhejiang university-Science A(Applied Physics & Engineering) 2007年第10期8卷 1633-1641页

作者： ZOU Wan-hong?1, DING Zhan1, YE Xiu-zi1, CHEN Zhi-yang2 (1State Key Lab. of CAD and CG, School of Computer Science and technology, zhejiang university, Hangzhou 310027, China) (2Software College, zhejiang university of technology, Hangzhou 310014, China) State Key Lab. of CAD CG School of Computer Science technology Zhejiang University Hangzhou 310027 China Software College Zhejiang University of Technology Hangzhou 310014 China

With the rapid development of 3D digital photography and 3D digital scanning devices, massive amount of point samples can be generated in acquisition of complex, real-world objects, and thus create an urgent need for advanced point-based processing and editing. In this paper, we present an interactive method for blending point-based geometries by dragging-and- dropping one point-based model onto another model’s surface metaphor. We first calculate a blending region based on the polygon of interest when the user drags-and-drops the model. Radial basis function is used to construct an implicit surface which smoothly interpolates with the transition regions. Continuing the drag-and-drop operation will make the system recalculate the blending regions and reconstruct the transition regions. The drag-and-drop operation can be compound in a constructive solid geometry (CSG) manner to interactively construct a complex point-based model from multiple simple ones. Experimental results showed that our method generates good quality transition regions between two raw point clouds and can effectively reduce the rate of overlapping during the blending.

关键词： Drag-and-drop Point cloud model Interactive blending Geometry modeling