检索结果-南通市图书馆

Hierarchically porous nitrogen-doped carbon foams decorated with zinc nanodots as high-performance sulfur hosts for lithium-sulfur battery

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2021年第9期32卷 2919-2922页

作者： Zhibo Liu Li Wang wantai yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China School of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Centre for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

To prevent polysulfides from dissolution into electrolyte,we propose a novel and simple approach to nitrogen-doped carbon foams which contain hierarchically porous structure and are decorated with zinc nanodots through one-pot carbonization and activation *** carbon foams,which serve as hosts for sulfur in lithium battery,can provide a conducting network and shorter diffusion length for ***,the zinc nanodots derived from the carbothermal reaction of ZnCl_(2) at high temperature can interact with sulfur/polysulfides by strong *** addition,the zinc nanodots can also facilitate the conversion reaction between Li_(2)S_(x)(2

关键词： Nitrogen-doped carbon foams Hierarchically porous Lithium-sulfur battery

Polymer nanoparticles with dendrimer-Ag shell and its application in catalysis

在线全文

学校读者我要写书评

暂无评论

Particuology 2013年第3期11卷 346-352页

作者： Gaofei Dang Yan Shi Zhifeng Fu wantai yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Polymer nanoparticles with dendrimer-Ag shell were prepared and their application in catalytic reduction of 4-nitrophenol （4-NP） was investigated. Cross-linked polystyrene （PS） microspheres were prepared through dispersion copolymerization of styrene, acrylic acid and crosslinking monomer 1, 2- divinylbenzene. PS microspheres with average size of 450 nm and narrow size distribution were used as support for the immobilization of dendrimer-Ag shell, The polyamidoamine （PAMAM） dendrimer shell was successively grafted onto the surface ofPS microspheres through repetitive Michael addition reaction of methyl acrylate （MA） and amidation of the obtained esters with large excess of ethylenediamine （EDA）. Silver nanoparticles were formed directly inside the PAMAM shell through reduction with NaBH4. The resulting PS@PAMAM-Ag nanopartides were packed in a stainless steel column and used successfully for catalytic reduction of 4-NP. This technique for packing catalytic polymer particles in a column could imnrove the efficiency of using the metal catalyst and the tedious seuaration in catalytic reaction.

关键词： Polymer nanoparticles Polyamidoamine dendrimer Dendrimer-metal Catalytic column Silver nanocatalyst

Visible light-induced thione-ene cycloaddition reaction for the surface modification of polymeric materials

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2018年第1期29卷 157-160页

作者： Li Wang Yi Wang Dong Chen wantai yang The State Key Laboratory of Chemical Resource Engineering College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

High-tech applications often demand the surface modification of polymeric materials using chemo- selective reactions that can proceed under mild conditions. In this paper, a feasible method for the surface modification of polymeric materials with low density polyethylene （LDPE） films as model substrates based on visible light-induced thione-ene cycloaddition reaction is proposed. This strategy includes three steps： 3-（（6-Hydroxyhexyl）oxy）-9H-xanthene-9-thione （HXT） containing visible light-reactive thio- carbonyl groups was firstly synthesized; Then thiocarbonyl groups were introduced onto LDPE films previously surface-grafted with poly（styrene-co-maleic anhydride） brushes by the reaction between the hydroxyl groups of HXT and anhydride groups; Functional alkenes were finally fixed onto the surface of LDPE films by thione-ene cycloaddition reaction conducted under visible light at room temperature （r.t.）, By FTIR, UV-vis spectroscopy, water contact angle test and XPS, we found that four typical functional alkenes, poly（ethylene glycol） methyl ethermethacrylate, 2-（perflurooctyl）ethyl methacrylate, 2, 3- dibromopropyl acrylate, and diethyl vinylphosphonate, can be successfully ligated, which confirmed the effectiveness and versatility of the present method.

关键词： Visible lightThone-ene cycloadditionSurface modificationPolymeric materialsLDPE

Sequential co-immobilization of β-glucosidase and yeast cells on single polymer support for bioethanol production

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2018年第12期61卷 1600-1608页

作者： Bin He Xing Zhu Changwen Zhao Yuhong Ma wantai yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing Laboratory of Biomedical Materials Beijing University of Chemical Technology Department of Mechanical Engineering The University of British Columbia Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education Beijing University of Chemical Technology Beijing Advanced Innovation Centre for Soft Matter Science and Engineering Beijing University of Chemical Technology

Co-immobilization of enzymes and microorganism is an effective way to enable cells to use nonmetabolizable substrates and accelerate reaction rate of overall process. Herein, a facile strategy to separately co-immobilize β-glucosidase(BG) and yeast cells on non-woven fabrics was developed. The BG was firstly in situ entrapped into poly(ethylene glycol)(PEG) network grafted on non-woven fabrics by visible light induced living/controlled graft polymerization. Then re-graft polymerization was performed on the as-formed BG loaded layer by taking advantage of living-grafting polymerization on its surface to in situ encapsulate yeast cells into the second PEG network layer. This layered structure of co-immobilization avoided possible interference between enzyme and cells. Viability assay of yeast cells demonstrated that most of cells were viable after immobilization. While immobilized BG showed decreased V_(max) compared to free BG, indicating that entrapping BG into inner PEG network layer restricted its accessibility with substrates. This co-immobilization sheet could successfully convert cellobiose to ethanol and a maximum of 98.6% bioethanol yield can be obtained after 48 h of simultaneous saccharification and fermentation(SSF). The co-immobilization sheet showed excellent reusability and could still reach more than 60% of original ethanol yield after reusing for 7 batches. Compared with the mixed co-immobilization, the sequential layered immobilization in this system showed better stability and higher ethanol yield.

关键词： immobilization graft polymerization bioethanol enzyme yeast cells

DuaI-Functionalized Hollow Polymer Particle as a pH-Responsive Adsorbent for Selective Removal of Basic Dye

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2017年第5期35卷 596-604页

作者： Dong Chen yang Liu Yan Qin Li Wang Yuhong Ma wantai yang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education Beijing University of Chemical Technology Beijing 190029 China

In the present work,novel dual-functionalized hollow polymer particles （DF-HPP） with high density of carboxylate and amino dual functional groups have been specially designed and fabricated to serve as high-performance adsorbent for selective removal of basic dye （methylene blue,b-MB,as a model dye）.Due to both the high surface area and the extremely high density of carboxylate and amino groups,the DF-HPPs exhibited excellent adsorption property for methylene blue （b-MB）,including high adsorption capacity,fast adsorption/desorption rates,unique pH-sensitivity and easy *** equilibrium adsorption data of b-MB on the DF-HPPs were evaluated using Freundlich and Langmuir isotherm models,and the equilibrium isotherm was better fit with Langmuir model with a maximum adsorption capacity of 538.8 mg/g at pH *** interestingly,the DF-HPPs showed a significant pH-dependent equilibrium adsorption capacity,which decreased dramatically from 516.1 mg/g to 24 mg/g as the solution pH decreased from 12 to *** dye-adsorbed DF-HPPs can be facilely and rapidly regenerated under mild condition （under weak acidic solution,pH 3,in 30 min） to recover both b-MB and the DF-HPPs,and the regenerated DF-HPPs can be reused for dye removal with high efficiency,indicating the exceptional recyclability of the DF-HPPs.

关键词： dual-functional hollow polymer particles adsorbent adsorption basic dye

Synthesis and Properties of Non-isocyanate Crystallizable Aliphatic Thermoplastic Polyurethanes

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2018年第5期33卷 1275-1280页

作者： LI Suqing DENG Yong ZHAO Jingbo ZHANG Zhiyuan ZHANG Jnuying yang wantai Key Laboratory of Carbon Fiber and Functional Polymers（Bering University of Chemical Technology） Ministry of Educatio State Key Laboratory of Chemical Resource Engineering College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

A simple non-isocyanate route synthesizing thermoplastic polyurethanes（TPUs） with good thermal and mechanical properties is described. Melt transurethane polycondensation of dimethyl 1,6-hexamethylene dicarbamate with 1,4-butanediol and 1,6-hexanediol was conducted at different molar ratios under the catalysis of tetrabutyl titanate. A series of crystallizable non-isocyanate TPUs with high molecular weight were prepared. The TPUs were characterized by gel permeation chromatography, FT-IR, 1 H-NMR, differential scanning calorimetry, thermogravimetric analysis, wide angle X-ray diffraction, AFM, and tensile tests. The TPUs exhibited Mn ranging from 12 500 to 26 400 g/mol, Mw from 16 700 to 56 400 g/mol, Tm up to 151.4 °C, and initial decomposition temperature over 241.8 °C. Their tensile strength reached 42.99 MPa with a strain at break of 30.00%. TPUs constructed simply with butylene, hexylene, and urethane linkages were successfully synthesized through a non-isocyanate route.

关键词： thermoplastic polyurethanes non-isocyanate route transurethane polycondensation properties dimethyl 1 6-hexamethylene dicarbamate

Synthesis of PE with Broad MWD Catalyzed by Supported Ziegler-Natta Catalyst Consisting of Cycloalkoxy Silane as IED

在线全文

学校读者我要写书评

暂无评论

China Petroleum Processing & Petrochemical Technology 2014年第2期16卷 91-96页

作者： Yu Mengshan Nie Yanpei Zhou Lu Yi Jianjun Huang Qigu Gao Kejing yang wantai State Key Laboratory of Chemical Resource Engineering Key Laboratory of Carbon Fiber and Functional Polymers Ministry of Education Beijing University of Chemical Technology Lab for Synthetic Resin Research Institution of Petrochemical Technology China National Petroleum Corporation

Two kinds of cycloalkoxy silane compounds were synthesized and used as the internal electron donors （IEDs） of supported Ziegler-Natta catalyst for ethylene polymerization to produce polyethylene with broader molecular weight distribution （MWD）, The effect of the structure and the amount of these IEDs on the polymerization performance was in- vestigated. The results implied that the molecular weight distribution of the obtained polyethylene could be adjusted by the incorporation of IEDs. SEM result showed that the morphology of catalyst particle was spherical and uniform in size distribution. The titanium content of these catalysts was higher, the active TiCl4 species were easily anchored on the support than that without adding IED, which was determined by ICE The GPC result confirmed that the polyethylene with broader molecular weight distribution in the range of from 23.4 to 25.6 was obtained using triethoxy-（-cyclopentyloxy）-silane （ED1） and triethoxy-（-cyclohexyloxyl）- silane （ED2） as the internal electron donors.

关键词： supported Ziegler-Natta catalyst polyethylene broader molecular weight distribution electron donor

Synthesis of cleavable multi-functional mikto-arm star polymer by RAFT polymerization: example of an anti-cancer drug 7-ethyl-10-hydroxycamptothecin(SN-38) as functional moiety

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2014年第7期57卷 995-1001页

作者： WEI XiaoHu GUNATILLAKE Pathiraja A MOAD Graeme RIZZARDO Ezio ROSSELGONG Julien yang wantai THANG San H. College of Materials Science and Engineering Beijing University of Chemical Technology Materials Science and Engineering The Commonwealth Scientific and Industrial Research Organisation(CSIRO)

Multi-functional mikto-arm star polymers containing three different arms [hydrophilic, SN-38-P（OEGMAs_9）11, cationizable, SN-38-P（DMAEMA）3s and hydrophobic, SN-38-P（BMA）26] were prepared by RAFT polymerization via an arm-first approach using a cleavable cross-linker. The star polymers were cleaved to the linear arms with tributylphosphine as a reducing agent. The decrease in molecular weight observed is consistent with the initial stars having approximately five arms, Blue fluorescence was observed when a solution of mikto-arm star was irradiated under a 365 nm light proving the retention of the SN-38 moiety during star formation by RAFT polymerization. Thus these polymer-drug conjugates can be considered as potential delivery vehicles for cancer therapy. The P（DMAEMA） arms can be quaternized using iodomethane, allowing star polymers to bind negatively charged small interfering RNA （siRNA） and potentially be used as a carrier for that material.

关键词： RAFT mikto-arm star polymer-drug conjugate cleavable polymer siRNA delivery cancer therapy

Interface-directed sol-gel:direct fabrication of the covalently attached ultraflat inorganic oxide pattern on functionalized plastics

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2010年第1期53卷 173-182,287-288页

作者： GAN ShengHua,yang Peng & yang wantai State Key Laboratory of Chemical Resource Engineering College of Materials Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China 1. State Key Laboratory of Chemical Resource Engineering College of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

For plastic electronics and optics,the fabrication of smooth,transparent and stable crack-free inorganic oxide films(and patterning) on flexible polymeric substrates with strong bonding strength and controllable thickness from nanometers to micrometers is a key but still remains a *** versatile inorganic oxides,silica oxide film as SiOx is especially important because this semiconductor material could provide crucial properties in devices or serve as a base layer for further multilayer *** this paper,we describe a new interface-directed sol-gel method to fabricate flexible high quality silicon oxide film onto commodity *** resulting crack-free silica film has strong covalent bonding with polymer substrates,homogeneous morphology with ultralow roughness,highly optical transparency,tunable thickness from nm to μm,and easy patterning *** fabrication strategy relies on a novel photocatalytic oxidation reaction by photosensitive ammonium persulfate(APS),which is able to fabricate highly reactive hydroxyl monolayer surface on inert polymeric *** kind of hydroxylated surface could serve as nucleation and growth sites to initiate surface sol-gel *** a result,well-defined SiOx film deposition(gelation) occurs,and patterned hydroxylation regions could be easily utilized to induce the formation of patterned oxide film *** strategy also excludes the requirements of clean room and vacuum devices so as to fulfill low-cost and fast fabrication *** application examples from such high quality SiOx layer onto plastics are given but should not be limited within *** is that oxygen permeation rate of SiOx deposited polymer film decreases 25 times than pristine polymer substrate,which is good for the potential packaging *** other one is that silanization monolayer,for example,3-aminopropyltriethoxysilane(APTES),could be successfully constructed onto silica layer through classical silanization reac

关键词： surface patterning silicon oxide sol-gel polymer surface modification functional coatings