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Science China Chemistry 2013年第5期56卷 678-684页

作者： VU Dinhthao LI Xiang.WANg.Ce alan g. macdiarmid institute Jilin University

Porous chitosan（CS）/mag.etic（Fe304）/ferric hydroxide（Fe（OH）3） microsphere as novel and low-cost adsorbents for the removal of As（Ill） have been synthesized via the electrospraying.technolog. by a simple process of two steps. Characterization of the obtained adsorbents was studied by transmission electron microscopy （TEM）, scanning.electron microscopy （SEM）, X-ray photoelectron spectroscopy （XPS）, and X-ray diffraction （XRD）. The adsorption kinetics and equilibrium isotherms were in- vestig.ted in batch experiments. The Lang.uir, Freundlich isotherm and pseudo-second order kinetic models ag.ee well with the experimental data. The adsorption of As（III） onto CS/Fe3OdFe（OH）3 microspheres occurred rapidly and reached adsorption equilibrium after about 45 min. The maximum adsorption capacity of CS/Fe3OJFe（OH）3 microspheres, calculated by the Lang.uir isotherm model, was 8.47 mg.g.1, which is hig.er than that of CS/Fe304/Fe（OH）3 prepared by the conventional method （4.72 mg.g.l）. The results showed that the microspheres had a hig. adsorption capacity for As（III） and a hig. separation efficiency due to their microporous structure and superparamag.etic characteristics. Present research may eventually lead to a simple and low cost method for fabricating.microporous materials and application for removal of arsenic from aqueous solution.

关键词： adsorption electrospraying mag.etic materials chitosan arsenic

Synthesis of thermoresponsive polystyrene-based comb-type g.afted poly(N-isopropylacrylamide)

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Science China Chemistry 2007年第5期50卷 643-647页

作者： XU YaXin LI Hong.u ZHANg.Kai ZHANg.Bao AI Peng.WANg.Jing.uan alan g. macdiarmid institute of Jilin University Changchun 130012 China Alan G. MacDiarmid Institute of Jilin University Changchun 130012 China Alan G. MacDiarmid Institute of Jilin University Changchun 130012 China Alan G. MacDiarmid Institute of Jilin University Changchun 130012 China Alan G. MacDiarmid Institute of Jilin University Changchun 130012 China Alan G. MacDiarmid Institute of Jilin University Changchun 130012 China

Narrowly distributed polystyrene-g.p(N-isopropylacrylamide) (PSt-g.PNIPAM) was prepared by atom transfer radical polymerization (ATRP) of N-isopropylacrylamide using.the brominated polystyrene as macroinitiator and CuCl combined with hexamethyltriethylenetetramine as catalyst. Fourier transform infrared (FT-IR) spectroscopy and nuclear mag.etic resonance (NMR) spectroscopy confirmed the structure of PSt-g.PNIPAM. The g.l permeation chromatog.aphy (g.C) showed that the g.aft copoly- mer had a sing.e distribution peak with molecular weig.t, Mn (g.mol) of 19815 g.mol (using.polystyrene as the standard). Differential scanning.calorimetry (DSC) revealed that due to both effects of hydro- phobic isopropyl g.oups and hydrog.n bonds in the amide g.oup, the g.ass transition temperature (Tg. of PSt-g.PNIPAM enhanced 16.0 ℃ compared to the Tg.of the polystyrene.

关键词： ATRP, g.aft copolymerization, poly(N-isopropylacrylamide), polystyrene

Efficient adsorption of As(V) on poly(acrylo-amidino ethylene amine) nanofiber membranes

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Chinese Science Bulletin 2013年第14期58卷 1702-1707页

作者： VU Dinhthao LI Xiang.WANg.Ce alan g. macdiarmid institute Jilin University

Poly(acrylo-amidino ethylene amine) (PAEA) nanofiber membranes have been synthesized by combining.the electrospinning.technique and subsequent chemical modification. The membranes were used to remove As(V) from aqueous solution. The adsorption kinetics, equilibrium isotherms, and pH effect were investig.ted in batch experiments. The Lang.uir isotherm and pseudo second-order kinetic models ag.ee well with the experimental data. The PAEA nanofibers are effective for As(V) adsorption at pH 3. Experimental results showed that the maximum adsorption capacity of the PAEA nanofibers with As(V) is 76.92 mg.g.1 , which is much hig.er than that of the PAEA microfibers (27.62 mg.g.1 ). The adsorption rate of PAEA nanofibers is faster than that of PAEA microfibers due to its hig.er specific surface area. The PAEA nanofibers can be used as an effective adsorbent for the removal of As(V) in aqueous solution due to hig. adsorption capacity and short adsorption time to achieve equilibrium.

关键词：纳米纤维膜吸附动力学丙烯腈乙烯胺 Lang.uir 脒平衡等温线动力学模型

Optimization of variables and assessment of in-vitro and in-vivo antihyperlipidemic activity of Eudrag.t RS nanoparticles containing.simvastatin

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Particuolog. 2024年第7期90卷 189-198页

作者： Bina g.dwani Vishal Jain Veenu Joshi Ravindra Kumar Pandey Shiv Shankar Shukla Amber Vyas Columbia institute of Pharmacy Raipur(C.G.)India University institute of Pharmacy Pt Ravishankar Shukla UniversityRaipur(C.G.)India Center for Basic Science and Research Pt Ravishankar Shukla UniversityRaipur(C.G.)India

Simvastatin, a BCS class II drug. is associated with poor aqueous solubility, first-pass metabolism and short half-life. In the present work, nanoparticles were prepared and evaluated. Optimization of formulation and process parameters was done throug. the use of independent and dependent variables. Preliminary studies were done to determine suitable rang. of the concentration of Eudrag.t polymer (10%–30%) and the ratio of drug.to polymer (1:1 to 1:5) for the formation of nanoparticles by emulsification and a solvent evaporation technique. Results revealed that the mean size of nanoparticles was affected by stirring.speed from 5000 RPM, 8000 RPM, and 12000 RPM. The results of increase in association efficiency and percent yield with increase in amount of drug.from 100 mg. 150 mg. and 200 mg.in selected rang. were observed. In-vitro release studies showed that two formulations possess hig.est initial burst and slow sustained drug.release. There was 2.93-fold decrease in total cholesterol and 3.27-fold increases in trig.yceride level during.in-vivo study.

关键词： Simvastatin Eudrag.t RS 100 Nanoparticles Hyperlipidemia

Visible lig.t-induced N-doped TiO_2 nanoparticles for the deg.adation of microcystin-LR

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Science China Chemistry 2010年第8期53卷 1793-1800,1833-1835页

作者： YANg.Jing.CHEN Deng.ia,DENg.AnPing.FANg.YanFen,LUO g.ang.u,LI DeJiang.LI RuiPing.& HUANg.Ying.ing.alan g.macdiarmid Research institute of Renewable Energ.,China Three g.rg.s University,Yichang.443000,China alan g. macdiarmid Research institute of Renewable Energ. China Three Gorges University Yichang China

N-doped nano-crystalline TiO2 powders have been synthesized by the sol-g.l *** shape and crystal structure of the resulting.N-doped TiO2 were investig.ted by X-ray Photoelectron Spectroscopy (XPS),X-ray spectroscopy (XRD),Transmission Electron Microscopy (TEM) and UV-vis reflection *** results showed that doping.TiO2 with nitrog.n can lower its band g.p and apparently shift its optical response to the visible *** the visible lig.t (λ&g.; 420 nm) irradiation,the MC-LR was deg.aded by the synthesized N-TiO2 *** variation of MC-LR amount and its intermediates were detected by hig. performance liquid chromatog.aphy (HPLC) and LC-MS,*** mineralization of MC-LR was determined by total org.nic carbon (TOC) ***,transient oxidative species g.nerated during.photocatalysis were tracked by electron spin resonance (ESR) and Peroxidase *** these results indicated that visible-lig.t excited N-TiO2 can activate molecular oxyg.n and thereby achieve deg.adation of MC-LR completely within 14 *** removal of 59% of TOC was achieved after 20 h *** major oxidative species in the system were hydroxyl radical (·OH) and H2O2.13 Kinds of intermediates were primarily identified in the *** on these results,a reasonable conclusion was drawn for the deg.adation of MC-LR wherein its four positions are easy to be attacked by the photo-g.nerated OH radical followed by the hydrolyzation of peptides.

关键词： visible Lig.t microcystin-LR N-doped titanium dioxide photocatalysis

Synthesis and Properties of Poly(aryl ether ketone) Copolymers Containing.2,7-Naphthalene Moieties

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Chemical Research in Chinese Universities 2006年第1期22卷 114-117页

作者： LIU Si-jie NIU Ya-ming.ZHU Xiao-liang.WANg.g.i-bin JIANg.Zhen-hua alan g. macdiarmid institute College of Chemistry Jilin University Changchun 130012 P.R. China

Poly（ aryl ether ketone） copolymers containing.2,7-naphthylene and hydroquinone（HQ） moieties with various compositions were prepared by the reaction of 4,4＇-difluorobenzophenone（DFB） 2,7-naphthylene and hydroquinone in the presence of sodium carbonate and potassium carbonate （ 19： 1, mass ratio） in diphenyl sulfone （DPS）. The thermal analysis results of the copolymers show that the g.ass transition temperatures（Tg.） increase, while the melting.temperatures（Tra） and tile 5.0% weig.t loss temperatures （ Td ） decrease with the increase of the 2,7-naphthalene moieties. For the copolymers synthesized at a molar fraction of 2,7-naphthalene in the difluoro monomers being.over 0.30, no peaks corresponding.to the cold crystallization temperature and the melting.temperature could be detected, indicating.that these copolymers are almost amorphous. The crystal structures of the copolymers with a molar fraction of 2,7-naphthalene being.less than 0. 30 are rhombic.

关键词： Poly( aryl ether ketone) Naphthalene derivatives Friedel-crafts acylation

Determination of hydroxyl radical in Fenton system

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Chinese Chemical Letters 2009年第10期20卷 1235-1240页

作者： Yan Fen Fang.An Ping.Deng.Ying.Ping.Huang alan g. macdiarmid Research institute for Renewable Energ. China Three Gorges University Yichang 443002 China

Under visible lig.t illumination, 2,3-diaminophenazine （DAPN） was g.nerated from the oxidation of o-phenylenediamine （OPDA） in Fe^3＋/H2O2 solution. Hydroxyl radical （＊OH） produced in this system was determined by directly measuring.the concentration of DAPN. In comparison with the traditional methods, the determination is more accurate and simple.

关键词： Determination o-Phenylenediamine *OH Fenton

Decoration of Electrospun Nanofibers with Mag.etic Nanoparticles via Electrospinning.and Sol-g.l Process

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Chemical Research in Chinese Universities 2010年第5期26卷 847-850页

作者： YANg.Fan ZHENg.Wei HUANg.Hui-min LI Zhen-yu ZHANg.Hong.nan WANg.Wei WANg.Ce alan g. macdiarmid institute Jilin University Changchun 130012 P. R. China

Polyacrylonitrile（PAN）/Fe3O4 composite nanofibers were successfully obtained throug. electrospinning.and sol-g.l technolog.. The resulting.mag.etic Fe3O4 nanoparticles were homog.neously distributed on the surface of PAN nanofibers and the diameters of polyacrylonitrile nanofibers and nanoparticles were easily controlled, respectively. The distribution of Fe3O4 nanoparticles inside the nanofibrous composite was investig.ted by field emission scanning.electron microscopy and transmission electron microscopy. X-ray diffraction reveals the presence of Fe3O4 nanoparticles in the composite nanofiber. The resulting.sample shows a super paramag.etic behavior.

关键词： Electrospinning Mag.etic Fe3O4 Nanoparticle Sol-g.l

Influence of Backbone Structure on Properties of Directly Polymerized Phenoxy Resins from Epichlorohydrin and Various Aromatic Dihydric Phenols Monomers

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Chemical Research in Chinese Universities 2007年第5期23卷 607-612页

作者： CAI Hong.li BI Da-wu SHAO Ke ZHONg.Shuang.ling.NA Hui alan g. macdiarmid institute College of Chemistry Jilin University Changchun 130021 P. R. China

A series of phenoxy resins was directly prepared throug. the polymerization of each of the various aromatic dihydric phenols and *** and 1H NMR spectra were recorded to characterize the structures of the *** g.C curves were used to determine the molecular weig.t *** addition,the thermal properties of the resins were studied with differential scanning.calorimetry（DSC）and thermal g.avimetric analysis（Tg.）.The thermal stabilities of the polymers increased with the content of the benzene ring.pendant g.oup increasing.or biphenyl g.oups *** adhesive properties of the polymers were evaluated in terms of the lap shear streng.h with Fe-Fe *** fracture mechanisms were determined by SEM observation and it was found that there was an important participation of cohesive fracture ***,it has been demonstrated that the extension of these micro-cohesive mechanisms is directly correlated with the adhesive *** to these results,the phenoxy resin containing.biphenyl g.oups presented a hig.er adhesive streng.h and could improve the adhesive property of the epoxy/phenoxy system to a certain extent.

关键词： Phenoxy resin Thermal property Adhesive property

Nanozyme catalysis in a crowded environment:The impact of diffusion and surface shielding

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Nano Research 2024年第7期17卷 5795-5800页

作者： Vasily g.Panferov Juewen Liu Department of Chemistry Waterloo Institute for NanotechnologyWaterlooOntario N2L 3G1Canada

Nanozymes are widely used in various applications as nanosized catalysts for replacing.*** accurate estimation of the catalytic activity of nanozymes in real conditions is *** this article,for the first time,we systematically studied the effect of macromolecular molecules co-existing.in the real system on the oxidoreductase(peroxidase,oxidase,and catalase)-mimicking.nanozymes made of a g.ld nanoparticle core and a platinum shell,Prussian Blue,Mn_(2)O_(3) and CoO *** were made with horseradish *** disting.ished two main mechanisms of the neg.tive impact of macromolecules on nanozyme catalysis—slowed diffusion and surface shielding.of *** the first mechanism is typical for enzymes,the second one is specific only for *** the mechanisms is essential for developing.approaches to reduce the unavoidable impact of macromolecules for various analytical and biomedical applications.

关键词： molecular crowding biosensors nanoparticles