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Crystal Structure of 4-(4-chlorophenyl)-7,7-dimethyl-2,5- dioxo-1,2,3,4,5,6,7,8-octahydroquinoline

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Chinese Journal of Structural Chemistry 2001年第6期20卷 459-461页

作者： TU Shu-Jiang ZHOU Jian-Feng GAO Yuan liu xiao-hong Department of Chemistry Xuzhou Normal University Department of Chemistry Huaiyin Teacher College Department of Chemistry Shenzhen University

The crystal structure of the title compound (C17H18ClNO2) has been determined by single-crystal X-ray diffraction. The crystal is monoclinic with space group C2/c, a=23.677(5), b=9.5333(2), c=14.027(3)? b=98.06(3), V=313.5(1)?, Mr=303.77, Z=8, Dc=1.287g/cm3, l=0.71073, m(MoKa)=0.247mm-1, F(000)=1280. The structure was refined to R=0.0600, wR=0.1959 for 2020 reflections with I>2s(I). X-ray analysis reveals that the dihedral angle between plane 1 [C(1)~C(6)] and plane 2 [N(1), C(10), C(11), C(7)] is 78.8(1) , between plane 2 and plane 3 [C(10), C(11), C(12), C(13), C(15)] is 3.95(7) .

关键词： quinoline synthesis crystal structure

Effects of back fat,growth rate,and age at first mating on Yorkshire and Landrace sow longevity in China

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Journal of Integrative Agriculture 2016年第12期15卷 2809-2818页

作者： HU Bin MO De-lin WANG xiao-ying liu xiao-hong CHEN Yao-sheng State Key Laboratory of Biocontrol School of Life SciencesSun Yat-Sen University

In the present study, genetic parameters for longevity and genetic correlations with back fat （BF）, average daily gain （ADG）, and first mating age （FMA） were estimated from 19 300 Yorkshire and 18 378 Landrace sows from 12 farms derived from one breeding system. General linear models （GLM） were employed to estimate genetic correlations with heritability （h2）. Longevity was defined by six different parameters （i.e., traits） and heritability ranged from h2=0.13 to 0.16 （P〈0.05） in both swine breeds. Genetic correlations between different longevity definitions were positive and high （r=0.79 to 0.99; P〈0.05）. BF exhibited low positive genetic correlations （r=0.12 to 0.15; P〈0.05） with longevity traits identified in both pig breeds which were dependent on trait definition, whereas ADG and FMA showed weak negative genetic correlations with longevity traits. The influence of BF, ADG, and FMA on longevity traits was examined by dividing the production and reproductive traits into several numerical groups; the influence of each longevity trait was subsequently analyzed among the different groups. The results indicated BF was the best trait to improve longevity among BF, ADG, and FMA, which showed positive effects for almost all longevity traits. For Yorkshire sows, gilts with over 18 mm BF were most desirable; Landrace with 10.6-13 mm BF were suitable for longevity. ADG was not favorable for gilt selection, because the correlation between growth rate and longevity very low. For FMA, our results indicated gilts mating before 230 days exhibited a longer life span. Therefore, we suggest farmers should select for thicker back fat and mate at an earlier age to improve sow longevity.

关键词： sow longevity back fat average daily gain first mating age

Highly Selective Preparation of 3-and 6-Modified Mannose/Altrose Derivatives

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Chemical Research in Chinese Universities 2006年第3期22卷 339-342页

作者： liu xiao-hong XIE Dang CHENG Chang-mei WANG Xia-yu GUO xiao-qiang ZHAO Yu-fen Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology of Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P.R. China Institute of Polymer Science and Engineering Xiangtan University Xiangtan 411105 P.R. China

A highly efficient method to get 3-and 6-modified mannose/ahrose derivatives for oligosaccharide synthesis is described. All the compounds were obtained exclusively with the combinations of 3-and/or 6-hydroxyl protect... 详细信息

关键词： Mannose Altrose Selective protection Selective deprotection

The Role of HIV Replicative Fitness in Perinatal Transmission of HIV

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Virologica Sinica 2011年第3期26卷 147-155页

作者： Xue-qing Chen Chang liu xiao-hong Kong （Laboratory of Medical Molecular Virology School of Medicine Nankai University Tianjin 300071 China）

Perinatal transmission of Human immunodeficiency virus(HIV),also called mother-to-child transmission(MTCT),accounts for 90% of infections in infants worldwide and occurs in 30%-45% of children born to untreated HIV-1 infected *** HIV-1 infected mothers,some viruses are transmitted from mothers to their infants while others are *** relationship between virologic properties and the pathogenesis caused by HIV-1 remains *** studies have demonstrated that one obvious source of selective pressure in the perinatal transmission of HIV-1 is maternal neutralizing *** studies have shown that viruses which are successfully transmitted to the child have growth advantages over those not transmitted,when those two viruses are grown ***,the higher fitness is determined by the gp120 protein of the virus *** suggests that the selective transmission of viruses with higher fitness occurred exclusively,regardless of transmission *** are many factors contributing to the selective transmission and HIV replicative fitness is an important one that should not be *** review summarizes current knowledge of the role of HIV replicative fitness in HIV MTCT transmission and the determinants of viral fitness upon MTCT.

关键词： Human immunodeficiency virus(HIV) Acquired immune deficiency syndrome(AIDS) Mother-to-child transmission(MTCT) Replicative fitness Gp120

Synthesis of Iron Chlorophyllins and Their Catalytic Performance for Aerobic Oxidation of Cyclohexene

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Chemical Research in Chinese Universities 2013年第3期29卷 526-532页

作者： liu xiao-hong LI Yong-jin YANG Wei-jun GUO Can-cheng College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China

A series of iron（III） chlorophyllins was prepared from silkworm excrement crude chlorophyll extract as a raw material. Aerobic oxidation of cyclohexene by using the prepared iron（III） chlorophyllins as biomimetic catalysts was studied under atmospheric pressure in the absence of reducing agent and solvent. The results indicate that chloro- phyll iron porphyrins have better catalytic performance than the industrial-applied iron tetraphenylporphyrin and cobalt tetraphenylporphyrin, and possess a higher selectivity for 2-cyclohexen-1-one. The smaller the polarity of iron（III） chlorophyllin＇s ligand is, the easier the catalytic oxidation of cyclohexene will be. Esterification products of iron（III） chlo- rophyllins can catalyze the oxidation of cyclohexene better than non-esterified iron（III） chlorophyllins, and therefore show a higher conversion of cyclohexene and a higher selectivity for 2-cyclohexen-l-one than the non-esterified ones. Among the six synthesized iron（III） chlorophyllin catalysts, iron（III） methyl-pyropheophorbide-a is the best biomimetic catalyst for the highest conversion of cyclohexene. The influences of catalyst＇s substituent, polarity and ring structure on the catalytic performance were discussed. The catalytic performance of iron（III） chlorophyllins improves with decreasing polarity, increasing conjugated degree of porphyrin＇s ring or enhancing chlorophyllins＇ stability. Possible mechanism of cyclohexene aerobic oxidation catalyzed by iron（III） chlorophyllins was also discussed.

关键词： Chlorophyll Iron chlorophyltin Air Cyclohexene Catalytic oxidation

Design of a node architecture for logic-calculation Nased all-optical network coding scheme

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 110-116,128页

作者： QU Zhi-jian XIE Yin-bao WANG Ju-hui liu xiao-hong School of Computer Science and Technology Shandong University of Technology

Network coding brings many benefits for multicast networks. It is necessary to introduce network coding into optical networks. Nevertheless, the traditional network coding scheme is hard to be implemented in optical networks because of the weak operation capability in photonic domain. In the paper, we focused on realizing two-channel network coding in all-optical multicast networks. An optical network coding scheme which can be realized via logic shift and logic XOR operations in photonic domain was proposed. Moreover, to perform the network coding scheme the coding node structure was designed and the operation principle and processes were illustrated in detail. In the end of the paper, the performance and the cost of different all-optical multicast mode were compared and analyzed.

关键词： network coding optical logic calculation coding node all-optical multicast

Synthesis and Crystal Structure of 3-(4-Ethoxyphenyl)-6-(phenoxymethyl)-1,2,4-triazolo[3,4-b][1,3,4]thiadiazole

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Chinese Journal of Structural Chemistry 2007年第5期26卷 567-571页

作者： LEI Xin-Xiang liu Miao-Chang xiao hong-Ping ZHANG An-Jiang ZHANG Li-Xue School of Chemistry and Materials Engineering Wenzhou University Zhejiang 325027 China

The title compound C18H16N4O2S has been synthesized by the reaction of 4-amino-3-（4-ethoxyphenyl）-5-mercapto-1,2,4-triazole with phenoxyacetic acid in phospho- rus oxychloride, and characterized by IR, NMR spectra and elemental analysis. Its structure was determined by single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P21/c with a = 1.4903（3）, b = 1.5230（2）, c = 0.9615（16） nm, Z = 4, V = 1.7769（5） nm^3, Dc = 1.317 g/cm^3, μ = 0.201 mm^-1, F（000） = 736, R = 0.0795 and wR = 0.2233. In the title compound, all rings are essentially planar.

关键词： X-ray diffraction crystal structure synthesis,spectral characterization thiadiazole

Functional Characterization of a NEM1-Like Gene in Magnaporthe oryzae

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Agricultural Sciences in China 2011年第9期10卷 1385-1390页

作者： WANG Ying JIAO Tian-lei liu xiao-hong LIN Fu-cheng WU Wei-ren Department of Agronomy College of Agriculture ＆ Biotechnology Zhejiang University Hangzhou 310029 P.R.China Institute of Biotechnology College of Agrieulture ＆ Biotechnology Zhejiang University Hangzhou 310029 PR. China School of Life Sciences Fujian Agriculture ＆ Forestry University Fuzhou 350002 P.R. China

Magnaporthe oryzae, a filamentous ascomycete fungus, is well known as the causal agent of rice blast. With the technology of suppression subtractive hybridization （SSH）, it was previously found that MGG_06001 （or named MoNEM1）, a gene of M. oryzae homologous to the NEM1 （nuclear envelope morphology protein 1） gene of baker＇s yeast （Saccharomyces cerevisiae）, is differentially expressed between the mature appressium and the conidium and mycelium. This study aimed to characterize the function of MoNEM1 gene by knocking it out using the method of target gene replacement. The AMoneml mutants exhibited reduced mycelial growth and conidiation. However, disruption of MoNEM1 gene does not affect the pathogenicity of M. oryzae on barley and rice.

关键词： Magnaporthe oryzae MoNEM1 conidiation growth pathogenicity

Structure and Quantum Chemistry Study on Hexaacetyl D-Mannose Hydrazine

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Chinese Journal of Structural Chemistry 2007年第8期26卷 911-916页

作者： CAO Rui liu xiao-hong CHENG Chang-Mei WANG Ru-Ji ZHAO Yu-Fen WANG Lai-Xi Key Laboratory of Bioorganic Phosphorus Chemistry ＆ Chemical Biology （Ministry of Education） Department of Chemistry Tsinghua University Beijing 100084 China Institute of Human Virology University of Maryland Biotechnology Institute University of Maryland USA

Hexaacetyl D-mannose hydrazine is one type of important intermediates in saccharide chemistry. In this paper, its single crystal was obtained and furthermore, X-ray diffraction and quantum chemistry calculation were performed. It belongs to orthorhombic system, space group P212121, with a=16.267（3）, b=19.263（3）, c=7.1948（12）A, Mr=446.41, Dc=1.315 g/cm^3, V=2254.5（6）A^3 and Z=4. Meanwhile, the experimental results also provide information for designing a kind of molecular switch based on the mannose nitrogenous derivatives.

关键词： hexaaeetyl D-mannose hydrazine crystal structure calculation of quantum chemistry molecular switch