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Na2S2O4-Mediated Cyclocondensations of 2,2＇-Disulfanediyldianilines with Aldehydes： A Facile and Inexpensive Method for the Synthesis of 2-Substituted Benzothiazoles

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Chinese Journal of Chemistry 2011年第2期29卷 314-320页

作者： Wang zhanglin Tang Riyuan Li Jinheng College of Chemistry and Materials Engineering Wenzhou University Wenzhou Zhejiang 325035 China

A facile and inexpensive method for the synthesis of 2-substituted benzothiazoles has been developed by Na2S2O4-mediated cyclocondensations of 2,2＇-disulfanediyldianilines with aldehydes. In the presence of Na2S2O4 and 4 ,A molecular sieves, a variety of 2-substituted benzotbiazoles were obtained from the reaction of 2,2＇-disulfanediyldianilines with aldehydes in moderate to high yields.

关键词： Na2S2O4 cyclocondensation 2,2'-disulfanediyldianiline aldehyde benzothiazole

Materials Substitute Evaluation in the Production of Cement

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Journal of Wuhan University of Technology(Materials Science) 2002年第2期17卷 97-98页

作者：张友棠 CHENJun-lin zhanglin HuazhongUniversityofScienceandTechnology

The substitute of materials based on the materials of the value analysis is a valid path which can lower the cost of products. If the substitute of materials can be applied in Chinese enterprises producing cement, the... 详细信息

关键词： value analysis substitute of materials cement

Estimating differential quantities from point cloud based on a linear fitting of normal vectors

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Science in China(Series F) 2009年第3期52卷 431-444页

作者： CHENG zhanglin ZHANG XiaoPeng Sino-French Laboratory LLAMA National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of SciencesBeijing 100080 China

Estimation of differential geometric properties on a discrete surface is a fundamental work in computer graphics and computer vision. In this paper, we present an accurate and robust method for estimating differential quantities from unorganized point cloud. The principal curvatures and principal directions at each point are computed with the help of partial derivatives of the unit normal vector at that point, where the normal derivatives are estimated by fitting a linear function to each component of the normal vectors in a neighborhood. This method takes into account the normal information of all neighboring points and computes curvatures directly from the variation of unit normal vectors, which improves the accuracy and robustness of curvature estimation on irregular sampled noisy data. The main advantage of our approach is that the estimation of curvatures at a point does not rely on the accuracy of the normal vector at that point, and the normal vectors can be refined in the process of curvature estimation. Compared with the state of the art methods for estimating curvatures and Darboux frames on both synthetic and real point clouds, the approach is shown to be more accurate and robust for noisy and unorganized point cloud data.

关键词： differential geometric properties point cloud normal fitting Weingarten matrix

Preparation and Luminescent Properties of ZnO Microrods and Microtubes

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Chinese Physics Letters 2004年第7期21卷 1366-1369页

作者： CHENJian-Gang GUOChang-Xin zhanglin-Li HUJun-Tao DepartmentofPhysics UniversityofScienceandTechnologyofChinaHefei230026 StructureResearchLaboratory UniversityofScienceandTechnologyofChinaHefei230026

Hexagonal ZnO microrods and sub-microrods have been prepared through thermal decomposition of an equimolar (0.1M) aqueous solution of Zn(NO3)2.4H2O and (CH2)6N4 at 90 degrees C for different times (10–46h). The microrods were transformed into hollow hexagonal ZnO microtubes when the growth time reached 46h. The Raman spectra and the photoluminescent (PL) spectra were measured. The PL spectra of microrods consist of two strong narrow near-UV bands at 380nm and 400nm assigned to free exciton emission and exciton–exciton collision, respectively. The PL spectrum of ZnO microtubes show only one peak in the near-UV region with peak located at 380nm with FWHM of about 20nm assigned to free exciton emission. When the growth time increased, the peak intensity of near-UV band decreased.

关键词： Excitons

Quasi-holography computational model for urban computing

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Visual Informatics 2019年第2期3卷 81-86页

作者： Baoquan Chen Qiong Zeng zhanglin Cheng Peking University China Shandong University China Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesChina

Vast amounts of data are produced with the development of smart cities and urban computing *** data is often captured from multiple sensors,with heterogeneous structures and highly decentralized *** data representation and smart computational models are required for more complex tasks in urban *** dwell deeply on two fundamental questions—can we provide an integrated data representation for the whole cyber–physical–social system?And,can we provide an integrated framework to choose the appropriate data for understanding a specific urban event?A holography data representation and the quasi-holography computational model have been proposed to address these *** describe case studies using the quasi-holography computational model,and discuss further problems to solve regarding our model.

关键词： Holography model Urban data representation

Radial growth and non-structural carbohydrate partitioning response to resin tapping of slash pine(Pinus elliottii ***)

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Journal of Forestry Research 2022年第2期33卷 423-433页

作者： Baoguo Du Qifu Luan zhanglin Ni Honggang Sun Jingmin Jiang College of Life Science and Biotechnology Ecological and Security Key Laboratory of Sichuan ProvinceMianyang Normal UniversityMianyang 621000People’s Republic of China Chair of Tree Physiology Institute of Forest SciencesAlbert Ludwigs-Universitat FreiburgGeorges-Köhler-Allee 5379110 FreiburgGermany Institute of Subtropical Forestry Research of the Chinese Academy of Forestry Fuyang 311400People’s Republic of China

Slash pine(Pinus elliottii ***)is a resin-producing species grown worldwide for significant economic benefits for wood *** tapping cre-ates a carbon sink at the expense of carbon allocation for growth and consequently,wood production may be ***-structural carbohydrates comprising starch and sugars stored in plant organs,may serve as intermediate pools between assimilation and ***,the effect of resin tapping between tree growth and non-structural carbo-hydrates is not well *** study investigated(1)the effects of resin tapping on radial growth,(2)the effects of resin tapping on non-structural carbohydrate pools in different compartments,and(3)the feasibility of resin pro-duction without disruption of tree *** one-year-old slash pines were subjected to resin tapping over two suc-cessive ***-structural carbohydrate concentrations in needles,branches,stem phloem,and roots of tapped and untapped trees in summer and winter were determined after the second year of resin *** results showed that tapping had no significant effects on annual *** was the dominant non-structural carbohydrate frac-tion,regardless of tissues and season,and constituted up to 99%of the total non-structural carbohydrates in the phloem and *** and fructose were the dominant sugars;sucrose was *** with the controls,tapped trees showed 26%lower non-structural carbohydrate concen-tration in the phloem above the tapping wound in summer,which was attributable to the decreased abundance of starch,glucose,fructose,and *** winter,the altered non-structural carbohydrate profiles in the phloem above the tap-ping wounding were minimised as a result of recovery of the sugar *** contrast to free sugars,which accu-mulated substantially in needles and branches during winter,starch was enriched in the phloem,roots,and current-year *** results provide evidence fo

关键词： Slash pine Localised effects Non-structural carbohydrate Resin tapping Radial growth

Learning local shape descriptors for computing non-rigid dense correspondence

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Computational Visual Media 2020年第1期6卷 95-112页

作者： Jianwei Guo Hanyu Wang zhanglin Cheng Xiaopeng Zhang Dong-Ming Yan National Laboratory of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China University of Maryland-College Park MarylandUSA Shenzhen VisuCA Key Lab Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenChina

A discriminative local shape descriptor plays an important role in various *** this paper,we present a novel deep learning framework that derives discriminative local descriptors for deformable 3D *** use local"geometry images"to encode the multi-scale local features of a point,via an intrinsic parameterization method based on geodesic polar *** new parameterization provides robust geometry images even for badly-shaped triangular *** a triplet network with shared architecture and parameters is used to perform deep metric learning;its aim is to distinguish between similar and dissimilar pairs of ***,a newly designed triplet loss function is minimized for improved,accurate training of the triplet *** solve the dense correspondence problem,an efficient sampling approach is utilized to achieve a good compromise between training performance and descriptor *** testing,given a geometry image of a point of interest,our network outputs a discriminative local descriptor for *** testing of non-rigid dense shape matching on a variety of benchmarks demonstrates the superiority of the proposed descriptors over the state-of-the-art alternatives.

关键词： local feature descriptor triplet CNN dense correspondence geometry image non-rigid shape

Basic Pattern in Atmospheric Turbulence Model

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Communications in Theoretical Physics 2004年第6期41卷 845-848页

作者： FUZun-Tao zhanglin LIUShi-Da LIUShi-Kuo SchoolofPhysics PekingUniversityBeijing100871China StateKeyLaboratoryfor~urbulenceandComplexSystem PekingUniversityBeijing100871China

From the controlling equations of atmosphere motion, Prandtl's mixing length theory is used to derive the atmospheric turbulence models, such as Burgers equation model and Burgers-KdV equation model. And then the projective Riccati equations are applied to solve these atmospheric turbulence models, where much more patterns are obtained, including solitary wave pattern, singular pattern, and so on.

关键词： atmospheric turbulence model Burgers-type equations projective Riccati equations

Probability Properties of Multi-contact in Protein Molecules

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Chemical Research in Chinese Universities 2003年第3期19卷 370-375页

作者： WANGXiang-hong KEJian-hong HUMin-xiao zhanglin-xi DepartmentofPhysics WenzhouNormalCollegeWenzhou325000P.R.China DepartmentofPhysics ZhejiangUniversityHangzhou310028P.R.China

The compact conformations of polymers are important because the native conformations of all bio-polymers with certain function are highly compact. The properties of mutil-contact bio-polymer chains were studied by Gaussian statistics of the random-flight chain. The theoretical expressions(were given, also), the calculations of probability distributions and correlation functions for different topologic cases were derived and made respectively. Comparison between single, double and triple contacts was also made. By means of setting the parameters, the results of the current calculations of the multiple contacts are just the same as those calculated by single, double or tripe contacts separately. It is a useful method to investigate native conformations of biopolymers. The probabilities of multi contacts and correlation functions between chain 's contacts were calculated for the Gaussian chains. Because the bond probability distributions are Gaussian 's distributions, the probability distributions of the separations of various points along the chains are always consecutive. All the contacts may break up into several groups, and each group consists of many contacts. Here we investigated the probability distribution from one group to three groups of contacts.

关键词： Random-flight model Protein molecule Correlation function