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Synthesis of Various Types of Silver Nanoparticles Used as Physical Developing Nuclei in Photographic Science

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Chinese Chemical Letters 2003年第6期14卷 645-648页

作者： Jun Ping ZHANG Li Qi SHENG Ping CHEN technical institute of Physics and Chemistry CASBeijing 100101

Ag nanoparticles used as physical developing nuclei in photographic science were prepared by reduction method. The as-formed Ag nanoparticle colloid was characterized by UV-Vis absorption spectrum, Atomic Force Microscopy(AFM) and Charge Coupled Device (CCD) technique. It is found that the source of Ag ions, the addition of surfactant and polymer, all have great influence on the size, topography and catalytic activity of Ag nanoparticles.

关键词： Ag nanoparticle AFM DTR.

Interaction of Hypocrellin B or Mono-cysteine Substituted Hypocrellin B with CT-DNA by Spectral Methods

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Chinese Chemical Letters 2003年第10期14卷 1054-1057页

作者： Jia Hong ZHOU, Sheng Qin XIA,Xue Song WANG, Bao Wen ZHANG, Yi CAO technical institute of Physics and Chemistry, Chinese Academy of Sciences,Beijing 100101 technical institute of Physics and Chemistry Chinese Academy of Sciences

The interaction of the anticancer drug hypocrellin B (HB) or the mono-cysteine substituted hypocrellin B (MCHB) and calf thymus deoxyribonucleic acid (CT-DNA) has been investigated using spectral methods. The results of UV-visible spectra show that the HB and MCHB could intercalate into the base-stacking domain of the CT-DNA double helix. The studies of fluorescence spectra and circular dichroism(CD) spectra also support the interacalation mechanism.

关键词： Hypocrellin B mono-cysteine substituted hypocrellin B CT-DNA interacalation mechanism.

Fabrication and Photoluminescence Properties of Hexagonal Micro-pyramids ZnO Powders by Combustion Synthesis

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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 700-702页

作者：陈皑张英 Zhoushan institute of Calibration and Testing for Qualitative and technical Supervision

The ZnO powder with hexagonal-pyramids structure was prepared by the low-temperature combustion process. Ammonium acetate was used as the fuels, whereas zinc nitrate acted as the oxidant. The effect of different ration between fuel and oxidant on the morphology and photoluminescence （PL） characteristic was studied. The formation of hexagonal-pyramids structure was discussed. The optimum preparing parameter for fine morphology is that the ratio of zinc nitrate and ammonium acetate is 1：5, and ignition temperature is 500 ℃. The PL measurement indicates all samples have the strong blue and yellow emission peak. The changes of surface energy of the polar surfaces result in the formation of micro-pyramids structure.

关键词： ZnO combustion synthesis PL morphology

Studies on Synthesis and Photochromism of a Novel Class of Fulgimide: (Z)-4-Oxazolylfulgimide

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Chinese Journal of Chemistry 2004年第1期22卷 100-102页

作者：肖军平韩勇陈懿李文樊美公 technical institute of Physics and Chemistry Chinese Academy of Sciences

A novel class of fulgimide, (Z)-4-oxazolylfulgimide ((Z)-1-benzyl-4-isopropylidene-3-[1-(2-aryl-5-methyl-oxazolyl)ethylidene]tetrahydropyrrole-2,5-dione), was synthesized by the reaction of (Z)-4-oxazolyl fulgide (4-isopropylidene-3-[1-(2-aryl-5-methyloxazolyl)ethylidene]tetrahydrofuran-2,5-dione) with benzyl amine. Photo-chromic property of (Z)-4-oxazolylfulgimide was studied. Compared with (Z)-4-oxazolylfulgide, the absorption maximum of the colored form of (Z)-4-oxazolylfulgimide is bathochromic-shifted. Substituents on the aryl ring af-fect the absorption maximum of the open form and the colored form of (Z)-4-oxazolylfulgimide.

关键词： Z)-4-oxazolyl fulgimide synthesis photochromism

STUDIES ON SELF-ASSOCIATIVE BEHAVIOR OF A NOVEL CATION AMPHIPHILIC POLYMER

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Chinese Journal of Polymer Science 2009年第4期27卷 593-596页

作者：吴飞鹏 technical institute of Physics and Chemistry Chinese Academy of Sciences

A novel associating polymer P(AEBA) was synthesized by radical polymerization of the cationic amphiphilic monomer,4-(2-(acryloyloxy)ethoxy)benzyl tri-ethyl ammonium bromide(AEBA),in aqueous solutions.P(AEBA) displays a strong tendency for self-association in aqueous solutions and is sensitive to the external stimulation such as added *** associative properties and morphologies of P(AEBA) were studied by fluorescnece probe technique,viscometry and *** dilute salt-free solutions P(AEBA) behaves as pol...

关键词： Amphiphilic polymer Self-association Aggregation structure

Graph Traversal and Top-Down Evaluation of Logic Queries

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Journal of Computer Science & Technology 1998年第4期13卷 300-316页

作者：陈阳军 technical institute of Changsha Changsha P.R. China

In this paper, an optimal method to handle cyclic and acyclic data relations in the linear recursive queries is proposed. High efficiency is achieved by integrating graph traversal mechanisms into a top-down evaluation. In such a way the subsumption checks and the identification of cyclic data can be done very efficielltly First, based on the subsumption checks, the search space can be reduced drastically by avoiding any redundant expansion operation. In fact, in the case of non-cyclic data, the proposed algorithm requires only linear time for evaluating a linear recursive query. On the other hand, in the case of cyclic data, by using the technique for isolating strongly connected components a lot of answers can be generated directly in terms of the intermediate results and the relevant path information instead of evaluating them by performing algebraic operations. Since the cost of generating an answer is much less than that of evaluating an answer by algebraic operations, the time consumption for cyclic data can be reduced by an order of magnitude or more.

关键词： recursive query top-down evaluation RQA/FQI strategy logic query,graph traversal

Scientometric analysis of physics (1979-2008):A quantitative description of scientific impact

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Science China(Physics,Mechanics & Astronomy) 2011年第1期54卷 176-182页

作者： ZHENG YanNing YUAN JunPeng PAN YunTao ZHAO XiaoYuan institute of Scientific and technical of Information of China Beijing 100038 China

Citations are a way to show how researchers build on existing research to further evolve *** citation count is an indication of the influence of specific *** importance of citations means that it is valuable to analyze the articles that are cited the *** research investigates highly-cited articles in physics (1979-2008) using citation data from the ISI Web of *** this study,1544205 articles were *** objective of the analysis was to identify and list the highly-productive countries,institutions,authors,and fields in *** on the analysis,it was found that the USA is the world leader in physics,and Japan has maintained the highest growth rate in physics research since ***,the research focus at Bell Labs and IBM has played important roles in physics.A striking fact is that the five most active authors are all Japanese,but the five most active institutions are all in the *** fact,only The University of Tokyo is ranked among the top 11 institutions,and only American authors have single-author articles ranked among the top 19 *** highest-impact articles are distributed across 25 subjects ***,Multidisciplinary has 424 articles,and is ranked at No.1 in total articles;followed by Physics,Condensed *** study can provide science policy makers with a picture of innovation capability in this field and help them make better ***,this study will stimulate useful discussion among scientists and research managers about future research directions.

关键词： high-impact articles domestic articles international articles social network analysis Web of Science

Enantioselectivity of Photochemical Reactions within Polymer Microcapsules

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Chinese Journal of Chemistry 2003年第1期21卷 96-97页

作者：马磊吴骊珠张丽萍佟振合 technical institute of Physics and Chemistry Chinese Academy of Sciences

Polymer microcapsule was employed as a reaction medium to achieve enantioselectivity in photochemical reduction of phenyl cyclohexyl ketone and photoelectrocyclization of tropolone methyl ether under the influence of various chiral inductors. In all cases, low but evident enantioselectivity was observed. The poor enantioselectivity is probably due to the facts that not all the capsules include simultaneously both the chiral inductor and the reactant molecules, and the wall of the microcapsule is not rigid enough to hold the reactant and the chiral inductor molecules in close contact.

关键词： microcapsule enantioselectivity photochemical reduction photoelectrocyclization phenyl cyclohexyl ketone tropolone methyl ether

Skin lesion classification system using a Knearest neighbor algorithm

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Visual Computing for Industry,Biomedicine,and Art 2022年第1期5卷 78-87页

作者： Mustafa Qays Hatem Renewable Energy Department Technical Institute of BaqubahMiddle Technical UniversityDyala 32001Iraq

One of the most critical steps in medical health is the proper diagnosis of the *** is one of the most volatile and challenging fields in terms of *** often require further testing,review of the patient’s history,and other data to ensure a proper ***,finding a method that can guarantee a proper trusted diagnosis quickly is *** approaches have been developed over the years to facilitate the diagnosis based on machine ***,the developed systems lack certain properties,such as high *** study proposes a system developed in MATLAB that can identify skin lesions and classify them as normal or *** classification process is effectuated by implementing the K-nearest neighbor(KNN)approach to differentiate between normal skin and malignant skin lesions that imply *** is used because it is time efficient and promises highly accurate *** accuracy of the system reached 98%in classifying skin lesions.

关键词： Machine learning Skin disease K-nearest neighbor Skin detection MATLAB Graphical user interface