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Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2-yl)-formimidoyl-(3-methyl-pyridin-2-yl) hydrazone

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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, zhejiang university 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 · 6H2O] 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 (H2O)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 = 2.123 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 H2O 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.

Clustering-based hyperspectral band selection using sparse nonnegative matrix factorization

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Journal of zhejiang university-science C(Computers and Electronics) 2011年第7期12卷 542-549页

作者： Ji-ming LI 1,2,Yun-tao QIAN 1 (1 School of Computer science and technology,zhejiang university,hangzhou 310027,china) (2 zhejiang Police College,hangzhou 310053,china) School of Computer science and technology Zhejiang University zhejiang Police College

Hyperspectral imagery generally contains a very large amount of data due to hundreds of spectral *** selection is often applied firstly to reduce computational cost and facilitate subsequent tasks such as land-cover classification and higher level image *** this paper,we propose a new band selection algorithm using sparse nonnegative matrix factorization (sparse NMF).Though acting as a clustering method for band selection,sparse NMF need not consider the distance metric between different spectral bands,which is often the key step for most common clustering-based band selection *** imposing sparsity on the coefficient matrix,the bands' clustering assignments can be easily indicated through the largest entry in each column of the *** results showed that sparse NMF provides considerable insight into the clustering-based band selection problem and the selected bands are good for land-cover classification.

关键词： Hyperspectral Band selection Clustering Sparse nonnegative matrix factorization

A general communication performance evaluation model based on routing path decomposition

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Journal of zhejiang university-science C(Computers and Electronics) 2011年第7期12卷 561-573页

作者： Ai-lian CHENG 1,Yun PAN 1,2,Xiao-lang YAN 2,Ruo-hong HUAN 3 (1 Department of Information science and Electronic Engineering,zhejiang university,hangzhou 310027,china) (2 Institute of VLSI Design,zhejiang university,hangzhou 310027,china) (3 College of Computer science and technology,zhejiang university of technology,hangzhou 310023,china) Department of Information science and Electronic Engineering Zhejiang University Institute of VLSI Design Zhejiang University

The network-on-chip (NoC) architecture is a main factor affecting the system performance of complicated multi-processor systems-on-chips (MPSoCs).To evaluate the effects of the NoC architectures on communication efficiency,several kinds of techniques have been developed,including various simulators and analytical *** simulators are accurate but time consuming,especially in large space explorations of diverse network configurations;in contrast,the analytical models are fast and flexible,providing alternative methods for performance *** this paper,we propose a general analytical model to esti-mate the communication performance for arbitrary NoCs with wormhole routing and virtual channel flow *** resolve the inherent dependency of successive links occupied by one packet in wormhole routing,we propose the routing path decomposition approach to generating a series of ordered link *** we use the traditional queuing system to derive the fine-grained transmission latency for each network *** to our experiments,the proposed analytical model provides a good approximation of the average packet latency to the simulation results,and estimates the network throughput precisely under various NoC configurations and ***,the analytical model runs about 10 5 times faster than the cycle-accurate NoC *** applications of the model including bottleneck detection and virtual channel allocation are also presented.

关键词： Analytical model Communication performance Network-on-chip (NoC) Queuing system Routing path decom-position Virtual channel

Variations in Laboratory-Scale Actinomycete Communities Exposed to Cadmium as Assessed by Denaturing Gradient Gel Electrophoresis Profiles

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Pedosphere 2010年第2期20卷 174-184页

作者： YUAN Hai-Ping,MIN Hang 2,LIU Ji,YAN Bo and L Zhen-Mei College of Life science,zhejiang university,hangzhou 310058 (china) [a] College of Life science Zhejiang University Hangzhou 310058 (China)

The actinomycete populations and functions in cadmium （Cd） contaminated soil were investigated by the cultivation- independent molecular methods. The genomic DNA was extracted and purified from soil adulterated with various con- centrations of Cd in the laboratory. The partial 16S rDNA genes were amplified by polymerase chain reaction （PCR） using specific primers bound to evolutionarily conserved regions within these actinomycete genes. The diversity in PCR- amplified products, as measured by denaturing gradient gel electrophoresis （EGGE）, was used as a genetic fingerprint of the population. Principle component analysis and Shannon-Weaver diversity index （H） analyses were used to analyze the DGGE results. Results showed that the two principal components accounted for only a low level of the total variance. The value H in contaminated soil was lower than that in the control at later stages of cultivation, whereas at earlier stages it was higher. Among the six sampling time points, the first, fifth and sixth weeks had the highest values of H. Significantly negative correlations between bioavallable Cd concentration and H values existed in the samples from weeks 2 （R = 0.929, P 〈 0.05） and 4 （R = 0.909, P 〈 0.05）. These results may shed light on the effect of Cd on the soil environment and the chemical behavior and toxicity of Cd to actinomycetes.

关键词： denaturing gradient gel electrophoresis genes principal component analysis Shannon-Weaver diversity index

Group sparse representation for image categorization and semantic video retrieval

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science china(Information sciences) 2011年第10期54卷 2051-2063页

作者： LIU YaNan 1,2 ,WU Fei 2 & ZHUANG YueTing 2 1 School of Information,zhejiang university of Finance & Economics,hangzhou,310018,china 2 College of Computer science and technology,zhejiang university,hangzhou,310012,china 1. School of Information Zhejiang University of Finance & Economics Hangzhou 310018 China2. College of Computer Science and Technology Zhejiang University Hangzhou 310012 China

Multimedia content analysis and management are a promising and challenging *** this paper we develop a novel approach to image representation,which we call group sparse representation (GSR),for image classification and video *** basic idea is to represent a test image as a weighted combination of all the training *** particular,we introduce two sets of weight coefficients,one for each training image and the other for each ***,we formulate our concern as a group nonnegative garrote *** resulting representations are sparse,and they are appropriate for discriminant *** on Caltech101 and PASCAL VOC2008 image dataset and TRECVID2005 video corpus testify that our proposed approach is efficient and effective.

关键词： compressive sensing group sparse representation bag-of-SIFT-words nonnegative garrote l1-minimization apcluster

Approximate merging of multiple Bézier segments

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Progress in Natural science:Materials International 2008年第6期18卷 757-762页

作者： Min Chenga,b,Guojin Wanga,* aInstitute of Computer Graphics and Image Processing,zhejiang university,hangzhou 310027,china bCollege of science,zhejiang university of technology,hangzhou 310032,china Institute of Computer Graphics and Image Processing Zhejiang University Hangzhou 310027 China College of science Zhejiang University of Technology Hangzhou 310032 China

This paper deals with the approximate merging problem of multiple adjacent Bézier curves with dierent degrees by a single Bézier curve,which is a frequently seen problem in *** unified matrix representation for precise merging is presented and the approx-imate merging curve is further derived based on matrix *** at the endpoints of curves is also discussed in the merging *** show that the method in this paper achieves satisfying merging results.

关键词： Computer-aided geometric design Bézier curve Approximate merging Matrix representation

An analytical solution to contaminant transport through composite liners with geomembrane defects

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中国科学：技术科学英文版 2010年第5期53卷 1424-1433页

作者： XIE HaiJian1,2,CHEN YunMin1 & LOU ZhangHua1,2 1MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering,zhejiang university,hangzhou 310058,china 2Institute of Hydrology and Water Resources Engineering,zhejiang university,hangzhou 310058,china 1. MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310058 China2. Institute of Hydrology and Water Resources Engineering Zhejiang University Hangzhou 310058 China

To investigate the performance of landfill composite liner system,a one-dimensional model was developed for solute transport through composite liners containing geomembrane *** analytical solution to the model was obtained by the method of Laplace *** results obtained by the presented solution agree well with those obtained by the numerical *** show that leachate head and construction quality of geomembrane(GM) have significant influences on the performance of the composite liners for heavy metal *** breakthrough time of lead decreases from 50 a to 19 a when the leachate head increases from 0.3 m to 10 *** is also indicated that the contaminant mass flux of volatile organic compounds(VOCs) induced by leakage can not be neglected in case of poor construction quality of the landfill barrier *** is shown that diffusion coefficient and partition coefficient of GM have great influences on solute transport through composite liners for *** breakthrough time of heavy metal ions will be greatly overestimated if the effects of diffusion and adsorption of clay and geosynthetic clay liner(GCL) are *** composite liner consisting of a geomembrane and a GCL provides a poor barrier for *** presented analytical solution is relatively simple to apply and can be used for preliminary design of composite liners,evaluating experimental results,and verifying more complex numerical models.

关键词： defect composite liner contaminant transport analytical solution leachate head landfill groundwater contamination

Use of the modified viral satellite DNA vector to silence mineral nutrition-related genes in plants: silencing of the tomato ferric chelate reductase gene, FRO1, as an example

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science china(Life sciences) 2008年第5期51卷 402-409页

作者： HE XiuXia1,2,JIN ChongWei1, LI GuiXin3, YOU GuangYi4, ZHOU XuePing3 & ZHENG ShaoJian4 1 Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education, College of Environmental and Resource science, zhejiang university, hangzhou 310029, china 2 College of Life science, Changchun university of science and technology, Changchun 130022, china 3 Institute of Biotechnology, zhejiang university, hangzhou 310029, china 4 State Key Laboratory of Plant Physiology and Biochemistry, College of Life science, zhejiang university, hangzhou 310058, china 1. Key Laboratory for Environmental and Ecosystem Health of the Ministry of Education College of Environmental and Resource Science Zhejiang University Hangzhou 310029 China 2. College of Life science Changchun University of Science and Technology Changchun 130022 China 3. Institute of Biotechnology Zhejiang University Hangzhou 310029 China 4. State Key Laboratory of Plant Physiology and Biochemistry College of Life Science Zhejiang University Hangzhou 310058 China

Virus-induced gene silencing (VIGS) is potentially an attractive reverse-genetics tool for studies of plant gene function, but whether it is effective in silencing mineral nutritional-related genes in roots has not been demonstrated. Here we report on an efficient VIGS system that functions in tomato roots using a modified viral satellite DNA (DNAmβ) associated with Tomato yellow leaf curl china virus (TYLCCNV). A cDNA fragment of the ferric chelate reductase gene (FRO1) from tomato was inserted into the DNAmβ vector. Tomato roots agro-inoculated with DNAmβ carrying both a fragment of FRO1 and TYLCCNV used as a helper virus exhibited a significant reduction at the FRO1 mRNA level. As a consequence, ferric chelate reductase activity, as determined by visualization of the pink FeBPDS3 complex was significantly decreased. Our results clearly demonstrated that VIGS system can be employed to investigate gene function associated with plant nutrient uptake in roots.

关键词： virus-induced gene silencing roots ferric chelate reductase

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. [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 （〉 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