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Degradation of benzophenone in aqueous solution by Mn-Fe-K modified ceramic honeycomb-catalyzed ozonation

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Journal of Environmental Sciences 2006年第6期18卷 1065-1072页

作者： HOU Yan-jun MA Jun SUN Zhi-zhong yu ying-hui zhao Lei School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

Comparative studies of ozonation alone, ceramic honeycomb-catalyzed and Mn-Fe-K modified ceramic honeycomb catalyzed ozonation processes have been undertaken with benzophenone as the model organic pollutant. The experimental results showed that the presence of Mn-Fe-K modified ceramic honeycombs significantly increased the removal rate of benzophenone and TOC compared with that achieved by ozonation alone or ceramic honeycomb-catalyzed ozonation. The electron paramagnetic resonance （EPR） experiments verified that higher benzophenone removal rate was attribute to more hydroxyl radicals generated in the Mn-Fe-K modified ceramic honeycomb-catalyzed ozonation. Under the conditions of this experiment, the degradation rate of all the three ozonation processes are increasing with the amount of catalyst, temperature and value of pH increased in the solution. We also investigated the effects of different process of ozone addition, the optimum conditions for preparing catalyst and influence of the Mn-Fe-K modified ceramic honeycomb after multiple-repeated use.

关键词： catalytic ozonation Mn-Fe-K modified ceramic honeycomb benzophenone

POLYMERIZATION OF METHYL METHACRYLATE WITH ORGANOLANTHANIDES AS SINGLE-COMPONENT CATALYSTS

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Chinese Journal of Polymer Science 2001年第1期19卷 85-87页

作者： Lai-qiang ying Xiao-wei Ba yu-ying zhao Gang Li Tao Tang ying-tai Jin Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

It was first found that Ind(2)Y(mu -Et)(2)AlEt2 and Ind(2)LnN(i-Pr)(2) (Ln = Y, Yb) exhibit extremely high catalytic activity in the polymerization of methyl methacrylate. The reactions can be carried out over a quite broad range of polymerization temperatures from -30 to 50 degreesC. PMMA with high molecular weight (7.8 x 10(-5)) and high isotacticity (94%) can be obtained by using Ind(2)Y(mu -Et)(2)AlEt2, and narrow molecular weight distribution (M-w/M-n < 1.5) can be obtained by using Ind(2)LnN(i-Pr)(2) (Ln = Y, Yb).

关键词： organolanthanide MMA polymerization

Cell Fate Switch during In Vitro Plant Organogenesis

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Journal of Integrative Plant Biology 2008年第7期50卷 816-824页

作者： Xiang yu zhao ying Hua Su ZhiJuan Cheng Xian Sheng Zhang State Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Tai'an 271018 China

Plant mature cells have the capability to reverse their state of differentiation and produce new organs under cultured conditions. Two phases, dedifferenUation and redifferentiation, are commonly characterized during in vitro organogenesis. In these processes, cells undergo fate switch several times regulated by both extrinsic and intrinsic factors, which are associated with reentry to the cell cycle, the balance between euchromatin and heterochromatin, reprogramming of gene expression, and so forth. This short article reviews the advances in the mechanism of organ regeneration from plant somatic cells in molecular, genomic and epigenetic aspects, aiming to provide important information on the mechanism underlying cell fate switch during in vitro plant organogenesis.

关键词： cell fate dedifferentiation plant organogenesis redifferentiation regeneration.

POLYMERIZATION OF ACRYLONITRILE WITH ORGANOLANTHANIDES AS SINGLE-COMPONENT CATALYSTS

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Chinese Journal of Polymer Science 2001年第1期19卷 89-91页

作者： Lai-qiang ying Xiao-wei Ba yu-ying zhao Gang Li Tao Tang ying-tai Jin Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022Chin

Ind_(2)Y(μ-Et)_(2)AlEt_(2) and Ind_(2)LnN(i-Pr)_(2)(Ln=Y,Yb)were used as a single-component catalyst for the polymerization of acrylonitrile(AN)*** regularity of polymerization of AN and stereoregularity of polyacrylonitrile(PAN)were also studied in both *** catalysts can produce PAN with molecular weight from 10,000 to 30,*** addition,the catalytic activity and molecular weights were increased by the addition of PhONa.

关键词： acrylonitrile organolanthanide polymerization

Determination of the Absolute Configuration of Rohitukine

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Chinese Chemical Letters 2003年第7期14卷 720-723页

作者： Dong Hui YANG Shao Qing CAI yu ying zhao Hong LIANG Department of Natural Medicines School of Pharmaceutical SciencesPeking UniversityBeijing 100083

The absolute configuration of rohitukine, isolated from the stem-bark of Dysoxylum binectariferum, was determined to be 5,7-dihydroxy-2-methyl-8-[4-(3S, 4R-3-hydroxy-1-methyl) -piperidinyl]-4H-1-benzopyran-4-one by X-ray crystallographic analysis on the crystal of 4-bromobenzoyl derivatives of rohitukine. At the same time, the modified Mosher method was proved to be unsuitable for determining the absolute configuration of C-3 position in rohitukine.

关键词： Dysoxylum binectariferum absolute configuration rohitukine.

Saikosaponin v-2 from Bupleurum chinense

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Chinese Chemical Letters 2001年第4期12卷 331-332页

作者： Hong LIANG Yan Jun CUI yu ying zhao Bin WANG Wen Xiu YANG Yi yu Department of Natural Medicines Peking UniversityBeijing 100083 Department of Biophysical Science and Technology Tianjin universityTianjin 300071

Saikosaponin v-2(1). was isolated li om the roots of the title plant and thc structure was identified on rhs basis of spectral anal? sis. Saikosaponin v-2 is a new compound. which was identified as 3 beta .16 alpha .23.28-tetrahydroxy-olean-11.13(18)-dien-30-oic acid-3-O-beta -D-glucopyranosyl- (1 -->2)glucopyranosyl-(1 -->3)-beta -D-fucopyranosol-30-O-xylitol ester.

关键词： Bupleurum chinense DC. Umbelliferae saikosaponin v-2.

Responses of phospholipase D and lipoxygenase to mechanical wounding in postharvest cucumber fruits

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第6期11卷 443-450页

作者： yu-ying zhao Chun-lu QIAN Ji-cheng CHEN Yan PENG Lin-chun MAO Department of Food Science and Nutrition College of Biosystem Engineering and Food Seience Zhejiang University Hangzhou 310029 China College of Horticulture and Gardening Yangtze University Jingzhou 434025 China

This study was to investigate the responses of phospholipase D（PLD） and lipoxygenase（LOX） to mechanical wounding in postharvest cucumber（Cucumis sativus ***-2） ***-associated Ca2＋ content,activities and gene expression of PLD and LOX,and contents of phosphatidylcholine（PC）,phosphatidylinositol（PI）,and phosphatidic acid（PA） were determined in cucumber fruits following mechanical *** show that PLD and LOX activities increased with the PLD and LOX mRNAs which are upregulated upon wounding,while membrane-associated Ca^2＋ content *** with the increase of PLD and LOX activities,accumulation of PA and losses of PC and PI were observed in all fruits,but there were differences of degrees between wounded and control *** suggest that PLD and LOX might be the main hydrolytic enzymes of phospholipids in postharvest cucumber fruits participating in the mechanical wounding *** activation of PLD and LOX might be the result of gene expression,which could be This study was to investigate the responses of phospholipase D（PLD） and lipoxygenase（LOX） to mechanical wounding in postharvest cucumber（Cucumis sativus ***-2） ***-associated Ca^2＋ content,activities and gene expression of PLD and LOX,and contents of phosphatidylcholine（PC）,phosphatidylinositol（PI）,and phosphatidic acid（PA） were determined in cucumber fruits following mechanical *** show that PLD and LOX activities increased with the PLD and LOX mRNAs which are upregulated upon wounding,while membrane-associated Ca2＋ content *** with the increase of PLD and LOX activities,accumulation of PA and losses of PC and PI were observed in all fruits,but there were differences of degrees between wounded and control *** suggest that PLD and LOX might be the main hydrolytic enzymes of phospholipids in postharvest cucumber fruits participating in the mechanical wounding *** activation of PLD and LOX might be

关键词： Cucumber Mechanical wounding Phospholipase D Lipoxygenase Phospholipid

A New Chromone Glycoside from Bupleurum Chinense

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Chinese Chemical Letters 1998年第1期9卷 69-70页

作者： Hong LIANG yu ying zhao Ru Yi ZHANG (Department of Phytochemistry, Beijing Medical University, Beijing 100083) Beijing Med Univ Dept Phytochem Beijing 100083 Peoples R China

A new chromone glycoside, saikochromoside A(1), was isolated from the roots of Bupleurum chinense DC. Its structure was determined on the bases of chemical and spectral analyses.

关键词： Bupleurum chinense DC saikochromoside A

A Dynamic Programming Algorithm for the κ-Haplotyping Problem

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Acta Mathematicae Applicatae Sinica 2006年第3期22卷 405-412页

作者： Zhen-ping Li Ling-yun Wu yu-ying zhao Xiang-sun Zhang Institute of Applied Mathematics Academy of Mathematics and Systems Science CAS Beijing 100080 China Mathematics Department of Beijing Wuzi University Beijing 101149 China Mathematics Department of Beijing Forest University Beijing China

The Minimum Fragments Removal （MFR） problem is one of the haplotyping problems： given a set of fragments, remove the minimum number of fragments so that the resulting fragments can be partitioned into k classes of non-conflicting subsets. In this paper, we formulate the κ-MFR problem as an integer linear programming problem, and develop a dynamic programming approach to solve the κ-MFR problem for both the gapless and gap eases.

关键词： Integer programming dynamic programming κ-haplotyping SNP