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Stereocontrol during the radical polymerization of methyl methacrylates with combined Lewis acids:Aluminium trichloride(AlCl_3) and iron dichloride tetrahydrate

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science china Chemistry 2010年第5期53卷 1141-1147页

作者： SANG Qian,FENG Ying ,DONG XiuCai & ZHAO JiRuo key laboratory of Rubber-Plastics,{2. of education Qingdao university of science and Technology,Qingdao 2.6042.china 1. key laboratory of Rubber-Plastics Ministry of Education Qingdao University of Science and Technology Qingdao 266042 China

The radical polymerization of methyl methacrylate(MMA) was carried out in the presence of combined Lewis acids of the AlCl3-FeCl2.*** with the polymerization produced in the presence of single Lewis acids,AlCl3 or FeCl2.the MMA polymerization in the presence of AlCl3-FeCl2.composite in CHCl3 or 1-butanol produced a polymer with a higher isotacticity and in toluene produced a polymer with a much higher isotacticity(mm=50%) .The molecular weight and polydispersity of PMMA in the presence of Lewis acids were similar with those in the absence of Lewis acids,although Lewis acids decelerate the polymerization of *** effects of the Lewis acids were greater in a solvent with a lower polarity.A possible stereocontrol mechanism of the polymerization was *** Lewis acid composite of AlCl3-FeCl2.readily formed a complex with growing *** complexes possessed apparent bulkiness that changes the direction of monomer addition to the growing radical center.

关键词： MMA radical polymerization tacticity Lewis acid stereocontrol polymerization

Syntheses, structures and magnetic properties of a family of one-dimensional M(Ⅱ)-lanthanide(Ⅲ) (M = Ni(Ⅱ) and Zn(Ⅱ)) coordination polymers

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science china Chemistry 2007年第3期50卷 308-317页

作者： ZHANG Wen, ZHAO Fei, LIU Tao & GAO Song beijing National laboratory for {2. sciences, State key laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and {2. Engineering, peking university, beijing 100871, china 1. beijing National laboratory for {2. sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

A series of 1D nickel(II)/zinc(II)-lanthanide(III) coordination polymers, [M(μ-L)2.n(NO3)3]n·solvents (HL = bis(2.pyridylcarbonyl)amine; M = Ni, Ln = Gd (1·NiGd), Tb (2.NiTb), Dy (3·NiDy), Ho (4·NiHo), Y (5·NiY); M = Zn, Ln = Gd (6·ZnGd), Tb (7·ZnTb), Dy (8·ZnDy), Ho (9·ZnHo); solvents = H2. or H2.-ethanol), was synthesized and characterized. All of the complexes are isostructural at 2.3 K and crystallize in the orthorhombic space group Fddd. Magnetic measurements were performed on 1―9, where weak ferromagnetic interaction is found in 1·NiGd, ferromagnetic interaction in 2.NiTb and 3·NiDy, and antiferromagnetic interaction in 4·NiHo. A remarkable dc magnetic field dependence of ac susceptibilities was found in this series of complexes.

关键词： nickel lanthanide 3d-4f coordination polymer magnetic property

Biomimetic preparation of elastomeric fibers with micro/nano structures on the surfaces

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Progress in Natural science:Materials International 2012年第5期22卷 493-501页

作者： Quanyong Liu a,Liqun Zhang c,Lei Jiang a,b a key laboratory of Bio-Inspired Smart Interfacial {2. and Technology of ministry of education,School of Chemistry and Environment,Beihang university,beijing 100191,PR china b beijing National laboratory for molecular {2.s(MNLMS),key laboratory of Organic Solids,Institute of Chemistry,Chinese Academy of {2.s,beijing 100190,PR china c State key laboratory of Organic-Inorganic Composites,beijing university of Chemical Technology,beijing 10002.,PR china [a] key laboratory of Bio-Inspired Smart Interfacial {2. and Technology of ministry of education School of Chemistry and Environment Beihang University Beijing 100191 PR China [b] beijing National laboratory for {2. sciences (MNLMS) Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 PR China [c] State key laboratory of Organic–Inorganic Composites Beijing University of Chemical Technology Beijing 100029 PR China

Bioinspired by the spinning of spider silks,the biomimetic preparation of elastomeric fibers with micro/nano structures on the surfaces was attempted,and as a result,three types of ultrafine fullvulcanized powdered nitrile-butadiene rubber(UFPNBR)/thermoplastic polyurethane(TPU) fibers were *** first fiber was only decorated by the micron-sized grooves on the surface,and the second fiber was dotted by both the micron-sized grooves and nanometer-sized spheres on the surface,while the third fiber was helical and with a concave-convex *** biomimetic preparation mainly consisted of four steps,and the formation mechanism was described as an integrated mechanism of diffusion,coagulation,self assembly,and microphase *** micro/nano structures on the fibers were controlled by changing the mass ratio of UFPNBR to TPU and environment of vertical *** UFPNBR/TPU elastomeric fibers were hoped to have an integrated function of superhydrophobicity,self cleaning,and mechanical improvement of toughness or strength.

关键词： Biomimetic preparation Elastomeric fiber Micro/nano structure Self assembly Spider silk

Crosstalk between signaling pathways of adrenoreceptors and signal transducers and activators of transcription 3(STAT3)in heart

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Acta Pharmacologica Sinica 2007年第2期28卷 153-161+163-165页

作者： Kai-zheng GONG Hui ZHANG Jian-hai DU You-yi ZHANG~2.Institute of Vascular Medicine,peking university Third Hospital,{2. laboratory of molecular cardiovascular sciences,ministry of education beijing 100083.china InstituteofVascularMedicine PekingUniversityThirdHospitalKeyLaboratoryofMolecularCardiovascularSciencesMinistryofEducationBeijing100083China

Recently,there have been important advancements in our understanding of thesignaling mechanisms of adrenoreceptors(AR)and signal transducers and acti-vators of transcription 3(STAT3).While their crucial roles in the pathologicalprocesses of the heart are well established,accumulating evidence suggests thereis a complex pattern of crosstalk between these 2.signaling ***,the potential for crosstalk occurs at multiple levels in each signaling cascade andinvolves receptor transactivation,G proteins,small GTPases,cyclic adenosine 3’,5’-monophosphate/protein kinase A,protein kinase C,scaffold/adaptor proteins,protein tyrosine kinases,and mitogen-activated protein *** addition,post-translational modification(eg acetylation)of STAT3 may provide a link betweenSTAT3 and AR *** particular,crosstalk between these 2.systems in theheart would appear to be dependent upon the species/tissue studied,develop-mental stage,and eliciting *** at least partly accounts for the epige-netic effects on biological function that is mediated by the 2.signaling *** of these mechanisms will provide new targets in the development ofnovel clinical strategies for heart disorders.

关键词： receptors adrenergic signal transduction STAT3 transcription factor heart

Posttranslational modulation on the biological activities of molecular chaperones

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science china(Life sciences) 2009年第6期52卷 515-520页

作者： CHANG ZengYi center for Protein science,School of Life science,National laboratory of Protein Engineering and Plant Genetic Engineering,peking university,beijing 100871,china center for Protein science School of Life Science National Laboratory of Protein Engineering and Plant Genetic Engineering Peking University Beijing 100871 China

molecular chaperones are a family of proteins that were first noticed to exist about 45 years ago from their increased transcription under heat shock *** a result,the regulation of their encoding genes has been subject to extensive *** studies revealed that the biological activities of molecular chaperones can also be effectively modulated at the protein *** ways of modulation so far elucidated include allosteric effect,covalent modification,protein-protein interaction,and con-formational alteration induced by such macro-environmental conditions as temperature and *** latter aspects were reviewed *** here is the importance of such immediate structural alterations that lead to an immediate activity increase,providing the immediate protection needed for the cells to survive the stress conditions.

关键词： molecular chaperone activity modulation sHsp Hsp60 Hsp70 Hsp90 Hsp100 HdeA DegP

What we have learned from transcript profile analyses of male and female gametes in flowering plants

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science china(Life sciences) 2010年第8期53卷 927-933页

作者： XIN HaiPing & SUN MengXiang key laboratory of the {2. of education for Plant Developmental Biology, College of Life science, Wuhan university, Wuhan 430072. china 1. key laboratory of the {2. of education for Plant Developmental Biology College of Life Science Wuhan University Wuhan 430072 China

Double fertilization is one of the predominant features of sexual reproduction in flowering plants but, because of the physical inaccessibility of gametes, the essential molecular mechanisms in these processes are largely unknown. Based on the techniques for isolating highly purified gametes from several species and well-developed methods for manipulating RNA from limited quantities of gametes, genome-wide investigations of gamete transcription profiles were recently conducted in flowering plants. In this review, we survey the accumulated knowledge on gamete collection and purification, cDNA library construction, and transcript profile analysis to assess our understanding of the molecular mechanisms of gamete specialization and fertilization.

关键词： sperm cell egg cell fertilization cDNA library gametogenesis transcript profile

Interaction between Plasminogen Activator Inhibitor Type-2.and Pre-mRNA Processing Factor 8

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 623-628页

作者： Jing FAN, Yu-Qing ZHANG, Ping LI, Chang TONG, Li TAN, and Yun-Song ZHU*Department of molecular Genetics, Shanghai Medical School of Fudan university, {2. laboratory of molecular Medicine,ministry of education, Shanghai 2.0032. china Department of molecular Genetics Shanghai Medical School ofFudan UniversityKey Laboratory of Molecular MedicineMinistry of EducationShanghai 200032China

The plasminogen activator inhibitor type-2.(PAI-2. dependent apoptosis protection is due to the 33 amino acids fragment located between helix C and D of PAI-2. this fragment may interact with some unknown intracellular proteins. In this study we used the fragment between helix C and D of PAI-2.as a bait to perform a yeast two-hybrid screen using a cDNA library constructed with HeLa cells during apoptosis, and retrieved a clone encoding 94 amino acid residues of C-terminus of pre-mRNA processing factor 8 (PRPF8). Co-immunoprecipitation experiments confirmed that PAI-2.could interact with PRPF8 in vivo. PAI-2.could bind PRPF8 C-terminal in both the inside and outside of nuclear. These results suggested that the interaction between these two proteins might not be involved in the apoptosis process.

关键词： plasminogen activator inhibitor type-2 pre-mRNA processing factor 8 (PRPF8) yeast two-hybrid system U5

PEG-g-poly(aspartamide-co-N,N-dimethylethylenediamino aspartamide):Synthesis,characterization and its application as a drug delivery system

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Progress in Natural science:Materials International 2009年第10期19卷 1305-1310页

作者： Dong Yang,Xiaohong Zhang,Li Yuan,Jianhua Hu key laboratory of {2. Engineering of Polymers(ministry of education),laboratory of Advanced Materials,Department of Macro{2. science,Fudan university,Shanghai 2.0433,china [a]key laboratory of {2. Engineering of Polymers (ministry of education) Laboratory of Advanced Materials Department of Macromolecular Science Fudan University Shanghai 200433 China

PEG-g-poly(aspartamide-co-N,N-dimethylethylenediamino aspartamide)(PEG-DMEDA-PASP) was synthesized by two-step ring-opening reactions of polysuccinimide(PSI) with a-methoxy-x-amino-poly(ethylene glycol) and N,*** polymer structure was confirmed by 1H NMR and *** resultant PEG-DMEDA-PASP with ammonium glycyrrhizinate(AMG) could form polymeric micelles in aqueous *** results of transmission electron microscopy(TEM) and dynamic light scattering(DLS) measurements revealed that these polymeric micelles were spherical particles with a narrow diameter distribution and that their average diameter was ca.70 *** polymeric micelles had high-loading capacity(58%) and encapsulation efficiency(70%) for *** results of in vitro release experiments showed that these polymeric micelles possessed sustained-release effects,with a release rate of 2.% within 3 h and 90% within 2. h.

关键词： PEG-g-poly(aspartamide-co-N,N-dimethylethylenediamino aspartamide) Polymeric micelle Drug delivery system Ammonium glycyrrhizinate

On the variation of water resource structure in the Lower Yellow River

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science china(Technological sciences) 2004年第z1期47卷 127-141页

作者： NI Jinren1, WANG Yudong1, QIAN Zhenghan1, LI Tianhong1 & ZHAO Yean2.1. Department of Environmental Engineering, peking university The {2. laboratory of Water and Sedi- ment sciences, ministry of education, beijing 100871, china 2. Institute of Hydraulic Research, Yellow River Conservancy Commission, Zhengzhou 450003, china 1. Department of Environmental Engineering Peking University 100871 Beijing China2. The Key Laboratory of Water and Sediment Sciences Ministry of Education 100871 Beijing China3. Institute of Hydraulic Research YellowRiver Conservancy Commission 450003 Zhengzhou China

In view of river functions and the Minimum Water Demand for River Ecosystem (MWDRE), the water resources in the Lower Yellow River is further divided into three portions, i.e. water available for ecosystem (WE), water exploitable for socioeconomic purposes (WS) and excess flood water (WF). Corresponding conceptions and practical significances are expounded in details. The annual amount of the three portions of water resources from 1950 to 2.01 is worked out on the basis of the daily hydrologic data, and the division of different portions is discussed. The results indicate that although the essential water demand for river functions is considered preferentially, the amount of the WE has decreased dramatically while its proportion increased gradually since the 1950s, and the shortage to the MWDRE increased markedly; both the amount and the proportion of the WS decreased notably. Since the 1990s, the actual water consumption for socioeconomic purposes in the lower reaches of the river basin has already exceeded the maximum amount of the WS and has to take over the WE which is already insufficient, hence not only the normal river functions are further disturbed and the river course shrinks greatly, but also the proportion and potential danger of the WF show no decreasing tendency in spite of the sharp decrease of upstream runoff.

关键词： the Yellow River, water resource structure, water available for ecosystem, water exploitable for socioeconomic purposes, excess flood water.