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A soluble polymer-supported NADH model:Synthesis and application

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Chinese Science Bulletin 2010年第25期55卷 2824-2828页

作者： MEI LianRui zhu xiao-qing CHENG Jin-Pei Department of Chemistry and the State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

A polyethylene glycol (PEG)-supported NADH model as a novel organic reductant was designed and synthesized. The reductions of various α,β-unsaturated ketones by the PEG-supported NADH model were examined,and the results showed that the reductions completely and quickly proceed with no catalyst at ambient temperature. The main advantages of this liquid-like PEG-supported NADH model are easy workup,and an optimal potential for recycling use and solvent-free for use in reactions.

关键词：辅酶模型可溶性聚合物合成应用聚乙二醇有机还原剂 NADH 环境温度

Heterolytic and homolytic C-D bond dissociation energies of NADH models in acetonitrile and primary isotopic effects on hydride versus hydrogen atom transfer reactions

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Science China Chemistry 2012年第10期55卷 2054-2056页

作者： CAO ChaoTun TAN Yue zhu xiao-qing State Key Laboratory of Elemento-Organic Chemistry Department of ChemistryNankai UniversityTianjin 300071China

Heterolytic and homolytic C D bond dissociation energies of three NADH models: BNAH-4,4-d 2 , HEH-4,4-d 2 and AcrD 2 in acetonitrile were first estimated by using an efficient method. The results showed that the heterolytic C D bond dissociation energies are 65.2, 70.2, and 81.9 kcal/mol and the homolytic C D bond dissociation energies are 72.66, 70.69, and 74.95 kcal/mol for BNAH-4,4-d 2 , HEH-4,4-d 2 , and AcrD 2 , respectively. According to the bond dissociation energy differences of isotope isomers, an interesting conclusion can be made that the primary kinetic isotope effects are dependent not only on the zero-point energy difference of the isotope isomers, but also on the types of C D bond dissociations, and the C D bond homolytic dissociations should have much larger primary kinetic isotope effects (26.9 28.8) than the corresponding C D bond heterolytic dissociations (3.9-5.4).

关键词： bond dissociation energies primary isotopic effects nicotinamide-adenine dinucleotide coenzyme models

A molecular half-adder and half-subtractor based on pyrylium

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Chinese Science Bulletin 2010年第25期55卷 2799-2802页

作者： CAO ChaoTun LIU Hui zhu xiao-qing CHENG Jin-Pei Department of Chemistry State Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

A very simple molecular cation, 4-(4-dimethylaminophenyl)-2,6-diphenylpyrylium, has been demonstrated to have a function of molecular half-adder and half-subtractor according to the detectable spectroscopic changes of the molecular system in response to the inputs of acid and base. Distinct algebraic operations can be performed in this reconfigurable molecular logic system.

关键词：分子离子半加器减法吡喃基础逻辑系统氨基苯基功能变化

Genetic Analysis and Molecular Mapping of Two SMV-Resistance Traits in Soybean:Adult-Plant Resistance and Resistance to Seed Coat Mottling

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Agricultural Sciences in China 2010年第1期9卷 11-18页

作者： WANG Kun LI Wen-fu ZHANG Lei LIU Chun-yan zhu xiao-shuang CHEN qing-shan HU Guo-hua Agriculture Academy Northeast Agricultural University/Crop Research and Breeding Center of Land-Reclamation of Heilongjiang Province/ National Research Center of Soybean Engineering and Technology/Soil Fertility and Environmental Resources Institute Heilongjiang Academy of Agricultural Sciences Harbin 150090 P.R.China

Soybean mosaic virus （SMV） could lead to adult-plant system diseases, and cause mottling of soybean seeds. Genetic analysis and molecular mapping were conducted using an F2 population and derived F3 families from two crosses of Dongnong 3C624 （susceptible）x Dongnong 8143 （resistant） and Dongnong 3C628 （susceptible）× Tie 6915 （resistant）. Simple sequence repeat （SSR） markers with bulked segregation analysis （BSA） were used to conduct genetic mapping of the resistance to SMV1 in the segregating populations. The results indicated that resistance to SMV1 in adultplants and the resistance to seed coat mottling in Dongnong 8143 and Tie 6915 was separately controlled by one single dominant gene. The two dominant genes were identified to be linked on the MLG F by Mendel＇s genetics and SSR genetic mapping. The order and distance of markers DPRSMV1 and DSRSMV1 were Sat 229-6.9 cM-DSRSMV1-4.6 cM-Sat_317-3.6 cM-DPRSMV1-5.2 cM-Satt335. The order and distance of markers TPRSMV1 and TSRSMV1 was Satt160-16.1 cM-TPRSMV1-7.3 cM-Satt516-2.0 cM-TSRSMV1-4.5 cM-Sat_133. This research provides the useful information for breeders to select the two types of SMV resistance simultaneously in soybean breeding through molecular marker-assisted selection （MAS）.

关键词： soybean SMV seed coat mottling genetic analysis SSR gene mapping

A THEORETICAL APPROACH TO P_(co_2) EVOLUTION IN THE ATMOSPHERE BASED ON ASSOCIATIONS OF SEDIMENTARY MINERALS

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Science China Chemistry 1989年第12期32卷 1509-1519页

作者：陈福朱笑青 Institute of Geochemistry Academia Sinica. Guiyang 550002 PRC

Based on the theory of pH evolution of sea water and the balance between the seawater and the atmosphere the authors discussed the problems about (i) the method ofcalculating P_(CO_2) in the ancient atmosphere with the associations of sedimentary miner-als; (ii) the evolution of P_(CO_2) values in the geologic history; (iii) the relations of thepH evolution of sea water with carbonate precipitations; and (iv) calculation of the pHlimit for some associations of sedimentary minerals and its corresponding P_(CO_2) valuesin the atmosphere. The authors pointed out that though carbonates had deposited little in the Archaean,the content of CO_2 gas in the Archaean atmosphere was very high and was gradually go-ing up to form a thick CO_2 atmosphere. Up to 2600 Ma ago, the P_(CO_2) had reached a gradeof 10- 50 atm. There was a general trend of evolution that from the early Proterozoicera to the present the depositional horizon of carbonate layers was gradually risingand finally surpassed the horizons of clay minerals and sulfides. The corresponding P_(CO_2)in the atmosphere was lowering from the thick CO_2 atmosphere to the present 0.03%atm. On the basis of the calculated P_(CO_2) sizes and its fluctuation characteristics thehistory of P_(CO_2) evolution can be divided into three major stages.

关键词： changes of sedimentary minerals pH conditions of carbonate precipitation evolution of P_(co_2) in the atmosphere

Enhancing ergosterol production in Pichia pastoris GS115 by overexpressing squalene synthase gene from Glycyrrhiza uralensis

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Chinese Journal of Natural Medicines 2015年第5期13卷 338-345页

作者： LIU Ying zhu xiao-qing LI Wen-Dong WEN Hao LIU Chun-Sheng School of Chinese Pharmacy Beijing University of Chinese Medicine Beijing Institute for Drug Control

The present study was designed to determine the effects of copy number variations(CNVs) of squalene synthase 1(SQS1) gene on the mevalonate(MVA) ***1 gene from ***(Gu SQS1) was cloned and over-expressed in Pichia pastoris *** recombinant *** strains containing different copy number of Gu SQS1 were *** was used to assay the level of ergosterol in all transgenic *** strains containing Gu *** analysis showed that the contents of ergosterol in all of the transgenic *** containing Gu SQS1 were higher than that in the negative *** with the increase of copy number of Gu SQS1,the content of ergosterol showed an increasing-decreasing-increasing *** contents of ergosterol in 10-copy-Gu SQS1 *** and 47-copy-Gu SQS1 *** were significantly higher than that in the rest recombinant *** *** conclusion,the CNVs of Gu SQS1 influence the content of secondary metabolites in the MVA *** present study provides a basis for over-expressing Gu SQS1 and increasing the content of glycyrrhizin in *** cultivars.

关键词： Glycyrrhiza uralensis GuSQS1 Over-expression Pichia pastoris Copy number variations

Antiviral effect of polysaccharide from Spirulina platensis(PSP) on HSV-2 in vitro

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Journal of Microbiology and Immunology 2006年第2期4卷 146-152页

作者： HONG YU xiao zhu WEN qing ZHANG RUI Lü Department of Microbiology College of Medicine Qingdao University Qingdao P. R. China

To explore the antiviral effect and mechanism of polysaccharide from Spirulina platensis （PSP） on herpes simplex virus type 2 （HSV-2）, a standard strain of HSV-2 （333 strain） was used to investigate the antiviral effect of PSP in vitro. PSP in various concentrations was applied to different stages of HSV-2 replication cycle. Finally, the virus infectivity （TCID50）, cytopathic effect （CPE）, and MTT staining method for viable cells （MTT assay） were used as markers to evaluate the effect of PSP on HSV-2. The quantity of HSV-DNA was detected by real-time fluorescence quantitative PCR （FQ-PCR）. The HSV-2 infected Vero cell tdtrastructures were observed by transmission electron microscopy （TEM）. The results showed that PSP had little cytotoxic effect on Vero cells, it could not directly inactivate HSV-2 infectivity. PSP not only interfered in adsorption of HSV-2 to Vero cells but also inhibited HSV-2 biosynthesis in the ceils. FQ-PCR results showed that the inhibitory rate on HSV- DNA also increased in a dose-dependent and time-dependent manner. TEM also confirmed that PSP exhibited pronounced inhibitory effect on HSV-2. In conclusion, the antiviral effect of PSP on HSV-2 may be attributed to the inhibition of virus adsorption, virus replication and synthesis in cells.

关键词： Polysaccharide from Spirulina platensis (PSP) HSV-2 FQ-PCR TEM

N-亚硝基吲哚系列化合物及其自由基负离子在乙腈介质中N—NO键断裂能的测定

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高等学校化学学报 2007年第12期28卷 2295-2298页

作者：李鑫朱晓晴王小小程津培南开大学化学系元素有机国家重点实验室天津300071

利用滴定量热技术并结合适当的热力学循环测定了乙腈溶液中7个取代的N-亚硝基吲哚化合物中N—NO键的异裂能和均裂能,能量范围分别为206.1～246.2 kJ/mol和119.1～124.6 kJ/mol.表明N-亚硝基吲哚均裂释放NO自由基（NO.）比异裂释放NO正... 详细信息

利用滴定量热技术并结合适当的热力学循环测定了乙腈溶液中7个取代的N-亚硝基吲哚化合物中N—NO键的异裂能和均裂能,能量范围分别为206.1～246.2 kJ/mol和119.1～124.6 kJ/mol.表明N-亚硝基吲哚均裂释放NO自由基（NO.）比异裂释放NO正离子（NO^＋）要容易得多,通过热力学循环得到的相应自由基负离子中N—NO键的异裂能和均裂能的能量范围分别为25.5～34.4和5.0～40.5 kJ/mol,表明所研究化合物的自由基负离子在室温下很不稳定.

关键词： N-亚硝基吲哚 N-亚硝基吲哚自由基负离子 N—NO键能滴定量热

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对《中图法》(第4版)美术类目问题的探讨

图书馆论坛 2010年第4期30卷 112-114页

作者：肖竹青漳州师范学院图书馆福建漳州363000

文章介绍了美术的定义,分析了《中图法》第4版优势及不足,指出美术类目设置与绘画理论不合理、类目设置有过粗、遗漏、欠完善、混乱等问题,提出了细化类目、新增设类目、统一类目、顺应时代需求修改类目等具体措施和建议。

关键词：《中国图书馆分类法》(第4版) 美术类目