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High norbornene incorporation in ethylene-norbornene copolymerization with a bis(α-alkyloxoimine) titanium-MAO catalyst

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Science china chemistry 2010年第8期53卷 1634-1640页

作者： GAO HaiYang1,2,HU Hao1 & WU Qing1,2 1Institute of polymer Science,school of chemistry and chemical engineering,sun yat-sen (Zhongshan) university,guangzhou 5102.5,china 2Key Laboratory for polymeric Composite and Functional Materials of Ministry of Education sun yat-sen (Zhongshan) university,guangzhou 5102.5,china Institute of polymer Science School of Chemistry and Chemical Engineering Sun Yat-Sen (Zhongshan) University Guangzhou China Key Laboratory for polymeric Composite and Functional Materials of Ministry of Education Sun Yat-Sen (Zhongshan) University Guangzhou China

A novel bis(α-alkyloxoimine) titanium(IV) complex was synthesized and used as a catalyst precursor to catalyze homo-and copolymerization of ethylene and *** titanium complex activated with methylalumoxane exhibits good activities for the homopolymerizations of ethylene and norbornene under high temperature to produce high-molecular-weight linear polyethylene and vinyl-type polynorbornene,***-norbornene copolymers with high molecular weight can also be produced by this *** incorporation of norbornene from 0 to 76 mol% in the copolymers can be controlled by varying the charged norbornene.13C NMr analyses show that the microstructures of the ethylene-norbornene copolymers with low norbornene incorporation are predominantly alternated and isolated norbornene units,while those with high norbornene incorporation are random polymers containing long norbornene sequences.

关键词： catalyst ethylene norbornene polymerization copolymerization

Cycloaddition mechanism for the resin-OsO_4-catalyzed of styrene: A DFT study

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Science china chemistry 2008年第1期51卷 19-24页

作者： ZHANG XingHui1, WANG KeTai1 & FANG ran2 1 College of chemical engineering, Gansu Unite university, Lanzhou 730000, china 2 College of chemistry and chemical engineering, sun yat-sen university, guangzhou 5102.5, china College of chemical engineering Gansu Unite University Lanzhou China College of chemistry and chemical engineering Sun Yat-sen University Guangzhou China

The postulated intermediates in the base-free and base-assisted addition of OsO4 to styrene have been investigated at the b3LYp/6-311G** level of the theory. N(CH3)2(ph) was chosen as the base of the resin-OsO4. According to our model calculations the [2+3] addition was found to be favorable with an activation of ract, the reaction barriers for the [2+2] cycloaddition remain high (>155.00 kJ/mol). In addition, the electronic structure analysis of the molecules was carried out by na- ture bond orbital (NbO). The computational results were in reasonable agreement with experimental results.

关键词： cycloaddition resin-OsO4 density functional theory

chemical weathering and chemical runoffs in the seashore granite hills in South china

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Science china Earth Sciences 2010年第8期53卷 1195-1204页

作者： GAO QuanZhou & TAO Zhen school of Geography and planning, sun yat-sen university, guangzhou 5102.5, china school of Geography and planning Sun Yat-sen University Guangzhou China

Surface runoffs and the contents of major ions and dissolved silicon were surveyed and analyzed based on weekly sampling for one year in a granite watershed of Zhuhai City, Guangdong province. The results demonstrated that the slope runoff played an essential role in feeding the rivulet during precipitation, whereas the groundwater was more important for the rivulet in the non-raining stages. Dissolved silicon, Na+, HCO3-, and Clions constituted the major chemical components of the rivulet water. Atmospheric CO2 and H2SO4 sourced from the oxidation of pyrite were the main erosive mediums in the natural chemical weathering. Natural chemical weathering, the wet and dry deposition of sea-salt, and acids precipitation contributed approximately equal shares of anions to the rivulet water. The ratio of NO3- to SO42- was more than 1.0 in the runoff of the studied seashore watershed, whereas it is less than 1.0 in the Xijiang river that is adjacent to the study area. This implied that the chemical composition of runoff is controlled mainly by the differences in atmospheric acid precipitation caused by human activities and lithology within the catchments under the same bio-climate zone. The CO2 flux consumed by the rock chemical weathering processes within the seashore granite watershed in South china was (0.35-1.37)×105 mol km-2 a-1.

关键词： chemical weathering granite ion sea-salt acid deposition CO2

Synthesis,crystal structures,electrochemical and spectroscopic properties of ruthenium(Ⅱ) complexes containing diamino-1,3,5-triazine derivatives

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Science china chemistry 2010年第10期53卷 2099-2105页

作者： CHEN Yu, XU WenChao, KOU JunFeng, WEI XuHui, YU boLe, CHAO Hui & JI LiangNian MOE Laboratory of bioinorganic and Synthetic chemistry, school of chemistry and chemical engineering, sun yat-sen university, guangzhou 5102.5, china MOE Laboratory of bioinorganic and Synthetic chemistry School of Chemistry and Chemical Engineering Sun Yat-Sen University Guangzhou China

Three ru(Ⅱ) complexes [ru(bpy)2(1-IQTNH)](ClO4)2 (1), [ru(bpy)2(2-QTNH)](ClO4)2 (2) and [ru(bpy)2(3-IQTNH)](ClO4)2 (3) (bpy = 2,2′-bipyridine, 1-IQTNH = 6-(isoquinolin-1-yl)-1,3,5-triazine-2,4-diamine, 2-QTNH = 6-(quinolin-2-yl)-1,3,5-triazine-2,4-diamine, 3-IQTNH = 6-(isoquinolin-3-yl)-1,3,5-triazine-2,4-diamine) have been synthesized and characterized by elemental analysis, 1H NMr spectroscopy, electrospray ionization mass spectrometry and X-ray crystallography. The electrochemical and spectroscopic properties of the complexes differ from those of [ru(bpy)3]2+ owing to the structural differences between the ligands and their complexes.

关键词： ruthenium(Ⅱ) complex diamino-1 3 5-triazine crystal structures electrochemistry spectroscopy

Synthesis, DNA-binding and photocleavage studies of ruthenium(Ⅱ) complexes [ru(btz)_3]^(2+) and [ru(btz)(dppz)_2]^(2+)

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Science china chemistry 2009年第9期52卷 1504-1511页

作者： YU HuiJuan, HUANG ShuMei, KOU JunFeng, LI LvYing, JIA HaiNa, CHAO Hui & JI LiangNian MOE Laboratory of bioinorganic and Synthetic chemistry, school of chemistry and chemical engineering, sun yat-sen university, guangzhou 5102.5, china MOE Laboratory of bioinorganic and Synthetic chemistry School of Chemistry and Chemical Engineering Sun Yat-Sen University Guangzhou China

Two new ruthenium(Ⅱ) complexes, [ru(btz)3](ClO4)2 (1) and [ru(btz)(dppz)2](ClO4)2 (2) (btz = 4,4′-bithi-azole, dppz = dipyrido[3,2-a:2′,3′-c]phenazine), have been synthesized and characterized by elemental analysis, 1H NMr, ES-MS and X-ray crystallography. The DNA binding behaviors of two complexes have been studied by spectroscopic and viscosity measurements. The results suggest that complex 1 binds to CT-DNA via an electrostatic mode, while complex 2 via an intercalative mode. Under irradiation at 365 nm, both complexes were found to promote the cleavage of plasmid pbr 322 DNA from supercoiled form Ⅰ to nicked form Ⅱ. The mechanism studies reveal that singlet oxygen 1O2 and hydroxyl radical (OH-) play a significant role in the photocleavage process.

关键词： ruthenium(Ⅱ) complex DNA binding DNA photocleavage pDT

FG020326-loaded nanoparticle with pEG and pDLLA improved pharmacodynamics of reversing multidrug resistance in vitro and in vivo

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Acta pharmacologica Sinica 2007年第6期28卷 913-920页

作者： Wen-jing DENG~2,Xiao-qiang YANG~2,Yong-ju LIANG~2,Li-ming CHEN~2,Yan-yan YAN~2,Xin-tao SHUAI~3,Li-wu FU~(2,4)~2 State Key Laboratory of Oncology in Southern china Cancer Center,sun yat-sen university,guangzhou 510060,china ~3 school ofchemistry and chemical engineering of sun yat-sen university,guangzhou 5102.5,china State Key Laboratory of Oncology in Southern china Cancer Center Sun Yat-Sen University Guangzhou China school of chemistry and chemical engineering of sun yat-sen university Guangzhou China

Aim:FG020326,a novel imidazole derivative,is a potent multidrug-resistance(MDr) modulator in vitro and in ***,FG020326 is ***-FG020326 is a FG020326-1oaded nanoparticle formed with diblock copolymers ofpoly (ethylene glycol)-block-poly (D,L-lactic acid) (pEG:pDLLA,pEDLLA) thatcan solubilize *** work was intended to evaluate the pharmacody-namics of pEDLLA-FG020326 on reversing MDr in vitro and in ***:Cytotoxicity was determined by tetrazolium *** intracellular accumulationand efflux of doxorubicin (Dox) were detected by fluorescence *** function of p-glycoprotein was examined by rhodamine 123 (rh123) accumu-lation detected by flow *** Kbv200 cell xenograft model was estab-lished to investigate the effect of pEDLLA-FG020326 on reversing MDr in ***:pEDLLA-FG020326 and FG020326 exhibited 56.4-and 35.9-fold activityin reversing Kbv200 cells to vincristine (VCr) resistance,respectively and 14.98-and 7.64-fold to Dox resistance,***-FG020326 was much stron-ger than FG020326,resulting in the increase of Dox and rh 123 accumulation andthe decrease of intracellular Dox extrusion in Kbv200 ***,pEDLLA-FG020326 exhibited more powerful activity than FG020326 in enhancing the effectof VCr against Kbv200 cell xenografts in nude mice,but did not appear more ***:The pharmacodynamics of FG020326 was improved by incorporatingit into a micellar nanoparticle formed with pEG-block-pDLLA copolymers.

关键词： FG020326 micellar nanoparticle multidrug resistance xenografts

rational design of metal selenides nanomaterials for alkali metal ion(Li^(+)/Na^(+)/K^(+))batteries:current status and perspectives

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rare Metals 2024年第5期43卷 1906-1931页

作者： rui sun Feng Xu Cai-Hong Wang Sheng-Jun Lu Yu-Fei Zhang Hao-sen Fan College of Materials Science and Metallurgy engineering Guizhou UniversityGuiyang550025China school of chemistry and chemical engineering Guangzhou UniversityGuangzhou510006China

recently,metal selenides have obtained widespread attention as electrode materials for alkali(Li^(+)/Na^(+)/K^(+))batteries due to their promising theoretical capacity and ***,metal selenides,similar to metal oxides and sulfides,also suffer from severe volume explosion during repeated charge/discharge processes,which results in the structure collapse and the following pulverization of electrode ***,it leads to poor cycle stability and influencing their further *** order to solve these issues,some special strategies,including elemental doping,coupling with carbon materials,synthesis of the bimetal selenides with heterostructure,etc.,have been gradually applied to design novel electrode materials with outstanding electrochemical ***,the recent research progress on metal selenides as anodes for alkali ion batteries is summarized,including the regulation of crystal structure,synthesis strategies,modification methods,and electrochemical mechanisms and ***,the challenges of metal selenides and the perspective for future electrode material design are *** is hoped to pave a way for the development of metal selenide electrode materials for the potential applications for alkali metal ion(Li^(+)/Na^(+)/K^(+))batteries.

关键词： rational design Metal selenides Nanostructure Li^(+) batteries Na^(+) batteries K^(+) batteries

Tetrabromobisphenol A and hexabromocyclododecane in sediments from the Zhujiang(pearl) river Estuary and South china Sea

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Acta Oceanologica Sinica 2024年第6期43卷 32-37页

作者： Chuyue Long Weiyan Yang Jiaxun Lu Yuanyue Cheng Ning Qiu sen Du Li Zhang Shejun Chen Yuxin sun Guangdong provincial Key Laboratory of chemical pollution and Environmental Safety/Key Laboratory of Theoretical chemistry of Environmental of Ministry of Education School of EnvironmentSouth China Normal UniversityGuangzhou 510006China South china Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China research Center of Harmful Algae and Marine biology Jinan UniversityGuangzhou 510632China university of Chinese Academy of Sciences Beijing 100049China Southern Marine Science and engineering Guangdong Laboratory Guangzhou 511458China

Marine sediments collected from the Zhujiang(pearl) river Estuary(ZrE) and South china Sea(SCS) were utilized to study the occurrence and spatial distribution of tetrabromobisphenol A(TbbpA) and hexabromocyclododecane(HbCDD).The levels of TbbpA and HbCDD in sediments ranged from not detected(nd) to 6.14 ng/g dry weight(dw) and nd to 0.42 ng/g *** concentrations in marine sediments were substantially higher than *** concentrations of TbbpA and HbCDD in the ZrE sediments were significantly greater than those in the SCS.α-HbCDD(48.7%) and γ-HbCDD(46.2%) were the two main diastereoisomers of HbCDD in sediments from the ZrE,with minor contribution of β-HbCDD(5.1%).HbCDD were only found in one sample from the northern *** enantiomeric fraction of α-HbCDD in sediments from the ZrE was obviously greater than 0.5,indicating an accumulation of(+)-α-*** enantiomers of HbCDD were not measured in sediments from the *** work highlighted the environmental behaviors of TbbpA and HbCDD in marine sediments.

关键词： tetrabromobisphenol A hexabromocyclododecane marine sediments Zhujiang river Estuary South china Sea

Metallomics:An integrated biometal science

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Science china chemistry 2009年第12期52卷 2055-2070页

作者： GE ruiGuang1,2 & sun HongZhe1 1 Department of chemistry and Open Laboratory of chemical biology,The university of Hong Kong,Hong Kong,china 2 Laboratory of Integrative biology,College of Life Sciences,sun yat-sen university,guangzhou 510006,china Department of chemistry and Open Laboratory of chemical biology The University of Hong Kong Hong Kong China Laboratory of Integrative biology College of Life Sciences Sun Yat-Sen University Guangzhou China

Metallomics is an emerging scientific area integrating the research fields related to the understanding of the molecular mechanisms of metal-associated life processes and the entirety of metal and metalloid species within a cell or tissue type. In metallomics,metalloproteins,metalloenzymes and other metal-containing biomolecules in a biological system are referred to as metallomes,similar to genomes and proteomes in genomics and proteomics,respectively. This review discusses the concept of metallomics with a focus on analytical techniques and methods,particularly the so-called hyphenated techniques which combine a high-resolution separation technique (gel electrophoresis/laser ablation,chromatography or capillary electrophoresis) with a highly sensitive detection method such as elemental (inductively coupled plasma,ICp) or molecular (electron spray ionization (ESI) or matrix-assisted laser desorption/ionization (MALDI)) mass spectrometry,or nuclear X-ray fluorescence/absorption spectrometry. The applications of these advanced analytical methods in the identification of metallo-/phospho-/seleno-proteins,probing of relationships between structure and function of metal-loproteins,and study of clinically used metallodrugs will be selectively outlined,along with their advantages and limitations.

关键词： metallomics metallome metallodrug metalloprotein chemical speciation