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Journal of Zhejiang university-Science B(Biomedicine & Biotechnology) 2008年第9期9卷 721-727页

作者： Jing ZHOU, nan HU, Ya-lin WU, Yuan-jiang PAN, Cui-rong SUN (department of chemistry, Zhejiang university, Hangzhou 310027, china) department of chemistry Zhejiang University Hangzhou 310027 China.

In order to investigate the antioxidant properties of the polysaccharides from the brown alga Sargassum fusiforme, the crude polysaccharides from S. fusiforme (SFPS) were extracted in hot water, and the lipid peroxidation inhibition assay exhibited that SFPS possessed a potential antioxidant activity. Hence, two purely polymeric fractions, SFPS-1 and SFPS-2 were isolated by the column of DEAE (2-diethylaminoethanol)-Sepharose Fast Flow, with their molecular weights of 51.4 and 30.3 kDa determined by high performance gel permeation chromatography (HPGPC). They were preliminarily characterized using chemical analysis in combination of infrared (IR) and nuclear magnetic resonance (NMR) spectroscopies and found to contain large amounts of uronic acids and β-glycosidical linkages. The antioxidant activities of these two SFPS fractions were evaluated using superoxide and hydroxyl radical-scavenging assays. The results show that the antioxidant ability of SFPS-2 was higher than that of SFPS-1, probably correlating with the molecular weight and uronic acid content.

关键词： Sargassum fusiforme Polysaccharide Antioxidant activity Uronic acid Molecular weight

THE　REACTION　OF　p－NITROPHENYLSULFONYLACETONITRILE　WITH　α，β－UNSATURATED　ESTERS　AND　NITRILES

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Chinese chemical Letters 1996年第4期7卷 305-308页

作者： Guo Ren YUE and Zheng Zhang(department of chemistry, Zhangye teachers’ college.Zhangye,734000department of chemistry, nanjing university, nanjing, 210093) ZHANGYE teachers COLL DEPT CHEMZHANGYE 734000PEOPLES R CHINA nanJING UNIV DEPT CHEMNANJING 210093PEOPLES R CHINA

Michael addition and an unexpected tandem addition-rearrangement reaction occurred when p-nitrophenylsulfonylacetonitrile(1)reacted with α-β-unsaturated estcrs and nitriles (2a-f).Different products can be obtained ... 详细信息

关键词：用成 ESTERS NITRILES OF REACTION THE UNSATURATED WITH AND

Concise and Effective Synthesis of Yakuchinone-A

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Chinese chemical Letters 1998年第4期9卷 361-363页

作者： Chu Sheng HUANG Xi Hui CHEN Yu Lin LI Hong Xing LIU Ying LI(department of chemistry and Applied chemical Institute, Guangxi teachers College nanning 530004 (National Laboratory of Applied Organic chemistry and chemical Institute, Lanzhou university, L Guangxi teachers Coll Dept Chem Nanning 530004 Peoples R China Guangxi teachers Coll Inst Appl Chem Nanning 530004 Peoples R China Lanzhou Univ Nat Lab Appl Organ Chem Lanzhou 730000 Peoples R China Lanzhou Univ Inst Chem Lanzhou 730000 Peoples R China Guangxi Univ Dept Chem Nanning 530004 Peoples R China

Yakuchinone-A, a natural strong pungent flavor isolated from Alpina oxyphylla, was synthesized starting from vanillin and cinnamaldehyde in five steps and in 62% overall yield.

关键词： 1,7-diarylheptanoids yakuchinone-A synthesis

Synthesis of Arsamacrocyclic Polyethers

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Chinese chemical Letters 1999年第8期10卷 665-666页

作者： Xin You CHEN Guo Feng YU Wen Tian TAO (department of chemistry. Xiaogan teachers College,Hubei 432100)(department of chemistry, Wuhan university,Wuhan 430072) Xiaogan teachers Coll Dept Chem Hubei 432100 Peoples R China Wuhan Univ Dept Chem Wuhan 430072 Peoples R China

The synthesis of eight new arsamacrocyclic Polyethers was described. The structures of these compounds were characterized by elemental analysis, IR, H-1-NMR and MS.

关键词： macrocyclic compound arsamacrocyclic polyether synthesis

Preparation and Structure of[(C5H4Me)2Sm(THF)(DME)][BPh4]

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Journal of Rare Earths 1999年第2期 14-17页

作者： Yuan Fugen (department of chemistry, Suzhou Railway teachers College, Suzhou 215009, china)Shen Qi (School of chemistry and chemical engineering,Suzhou university,Suzhou 215006,china)Sun Jie (Shanghai Institute of Organic chemistry,Chinese Acade

Ｔｈｅｃｈｅｍｉｓｔｒｙｏｆｃａｔｉｏｎｉｃｃｏｍｐｌｅｘｅｓｆｏｒｔｒａｎｓｉｔｉｏｎｍｅｔａｌｓａｎｄａｃｔｉｎｉｄｅｅｌｅｍｅｎｔｓｈａｓｄｅｖｅｌｏｐｅｄｒａｐｉｄｌｙ．Ｔｈｉｓｉｎｔｅｒｅｓｔａｒｉｓｅｓ... 详细信息

Ｔｈｅｃｈｅｍｉｓｔｒｙｏｆｃａｔｉｏｎｉｃｃｏｍｐｌｅｘｅｓｆｏｒｔｒａｎｓｉｔｉｏｎｍｅｔａｌｓａｎｄａｃｔｉｎｉｄｅｅｌｅｍｅｎｔｓｈａｓｄｅｖｅｌｏｐｅｄｒａｐｉｄｌｙ．Ｔｈｉｓｉｎｔｅｒｅｓｔａｒｉｓｅｓｆｒｏｍｔｈｅｓｕｇｇｅｓｔｉｏｎ...

关键词： Rare earths Cationic complex Samarium Methylcyclopentadienyl Crystal structure

Synthesis of α-[2-(2, 4-Dichlorophenoxy) Propionyloxy] Alkyl Phosphonates

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Chinese chemical Letters 1997年第11期8卷 943-944页

作者： Jun WANG Hong Wu HE and Zhao Jie LIU(Institute of Organic Synthesis, Central china Normal university, Wuhan, 430070)(department of chemistry, Xiaogan teachers College, Hubei, 432100) Cent china Normal Univ Inst Organ Synth Wuhan 430070 Peoples R China Xiaogan teachers Coll Dept Chem Hubei 432100 Peoples R China

The synthesis of thirteen new compounds α - [2 - (2, 4 -dichlorophenoxy) propionyloxy] alkyl phosphonates was described. The structures of these compounds were characterized by IR, 1H-NMR and MS.

关键词： Synthesis of Propionyloxy Dichlorophenoxy Alkyl Phosphonates

Carbon coated LaFe_(0.92)Pd_(0.08)O_(3) composites for catalytic transfer hydrogenation:Balance in the ability of substrates adsorption and conversion

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nano Research 2024年第5期17卷 3724-3732页

作者： Bowen Wang nan Zhang Ping Xiao Jian Zhang Sónia A.C.Carabineiro Junjiang Zhu Hubei Key Laboratory of Biomass Fibers and Eco-dyeing&Finishing College of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhan 430200China College of chemistry and Materials engineering Wenzhou UniversityWenzhou 325035China LAQV-REQUIMTE Department of ChemistryNOVA School of Science and TechnologyUniversidade NOVA de LisboaLargo da Torre2829-516 CaparicaPortugal

Catalytic transfer hydrogenation(CTH)is a green and efficient pathway for selective hydrogenation of unsaturated aldehydes and ***,managing the abilities of solid catalysts to adsorb substrates and to convert them into desired products is a challenging ***,we report the synthesis of carbon coated LaFe_(0.92)Pd_(0.08)O_(3) composites(LFPO-8@C)for CTH of benzaldehyde(BzH)into benzyl alcohol(BzOH),using isopropanol(IPA)as hydrogen *** coating with carbon improves the ability to adsorb/transfer reactants from solution to active sites,and the doping of Pd2+at Fe3+site strengthens the ability of LaFeO_(3) to convert BzH into BzOH.A balanced point between them(i.e.,abilities to adsorb BzH and to convert BzH into BzOH)is obtained at LFPO-8@C,which exhibits a BzOH formation rate of 3.88 mmol·gcat^(-1)·h^(-1) at 180℃ for 3 h,which is 1.50 and 2.72 times faster than those of LFPO-8 and LaFeO_(3)@C.A reaction mechanism is proposed,in which the acidic sites(e.g.,Fe^(4+),oxygen vacancy)are used for the activation of C=O bond of BzH and O-H bond of IPA,and the basic sites(e.g.,lattice oxygen)for the activation ofα-H(O-H)bond of IPA.

关键词： LaFe_(0.92)Pd_(0.08)O_(3) porous carbon catalytic transfer hydrogenation isopropanol reaction mechanism

The Synthesis of Podophyllotoxin Derivatives with Macrocyclic Dilactone

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Chinese chemical Letters 1999年第4期10卷 275-276页

作者： Min YANG Ning CHEN Xin Fu PAN Bing Chang QIN(department of chemistry. National Laboratory of Applied Organic chemistry,Lanzhou university, Lanzhou, 730000)(department of chemistry, Anyang teachers College. Anyang 455002) Lanzhou Univ Dept Chem Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China Anyang teachers Coll Dept Chem Anyang 455002 Peoples R China

Starting from podophyllotoxin, five new derivatives with macrocyclic dilactone 5 similar to 9 have been synthesized,and their structures were confirmed by IR, MS,H-1 NMR as well as HRMS. The key step is cyclization by... 详细信息

关键词： podophyllotoxin derivatives macrocyclic dilactone synthesis

Mitigated reaction kinetics between lithium metal anodes and electrolytes by alloying lithium metal with low-content magnesium

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Journal of Energy chemistry 2024年第8期95卷 644-650,I0014页

作者： Yang-Yang Wang Ya-nan Wang nan Yao Shu-Yu Sun Xiao-Qing Ding Chen-Xi Bi Qian-Kui Zhang Zhao Zheng Cheng-Bin Jin Bo-Quan Li Xue-Qiang Zhang Jia-Qi Huang School of Materials Science and engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green chemical Reaction engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China College of Materials and chemistry China Jiliang UniversityHangzhou 310018ZhejiangChina

Lithium(Li)metal is regarded as a promising anode candidate for high-energy-density rechargeable ***,Li metal is highly reactive against electrolytes,leading to rapid decay of active Li metal ***,alloying Li metal with low-content magnesium(Mg)is proposed to mitigate the reaction kinetics between Li metal anodes and *** atoms enter the lattice of Li atoms,forming solid solution due to the low amount(5 wt%)of *** atoms mainly concentrate near the surface of Mg-alloyed Li metal *** reactivity of Mg-alloyed Li metal is mitigated kinetically,which results from the electron transfer from Li to Mg atoms due to the electronegativity *** on quantitative experimental analysis,the consumption rate of active Li and electrolytes is decreased by using Mgalloyed Li metal anodes,which increases the cycle life of Li metal batteries under demanding ***,a pouch cell(1.25 Ah)with Mg-alloyed Li metal anodes delivers an energy density of 340 Wh kg^(-1)and a cycle life of 100 *** work inspires the strategy of modifying Li metal anodes to kinetically mitigate the side reactions with electrolytes.

关键词： Lithium metal anodes Alloying Anode/electrolyte interface Reaction kinetics Pouch cell

10种黄酮类抗氧化剂活性差异的理论阐释(英文)

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生物化学与生物物理学报 2000年第4期32卷 317-321页

作者：张红雨陈德展淄博学院生物与化学工程系!淄博255091 山东师范大学化学系!济南250014

借助理论方法 ,包括结构活性关系 (SAR)和量子化学计算阐释了 1 0种黄酮类抗氧化剂清除自由基活性的差异。发现SAR可以定性地解释抗氧化剂的活性差异 ,而半经验量子化学方法AM1计算的理论参数ΔHOF(抗氧化剂与其抽氢反应产生的自由基... 详细信息

借助理论方法 ,包括结构活性关系 (SAR)和量子化学计算阐释了 1 0种黄酮类抗氧化剂清除自由基活性的差异。发现SAR可以定性地解释抗氧化剂的活性差异 ,而半经验量子化学方法AM1计算的理论参数ΔHOF(抗氧化剂与其抽氢反应产生的自由基的生成热之差 )可以对此给出进一步的解释。ΔHOF与抗氧化剂清除自由基速率常数的对数还有一定相关性 ,相关系数为 -0 .752 3。因此理论方法在解释抗氧化剂的活性差异方面是有效的 ,同时也证明另一个理论参数 ,最高占据分子轨道 (HOMO)能级在这方面是无效的。

关键词： AM1方法抗氧化剂黄酮类化合物自由基结构-活性关系