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Effect of PEG additives on properties and morphologies of polyetherimide membranes prepared by phase

Jian CHEN, Jiding LI, Xia ZHAN, Xiaolong HAN, Cuixian CHEN,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 300-306 doi: 10.1007/s11705-009-0280-8

摘要： This study investigated the effect of poly(ethylene glycol) (PEG) additive as a pore-former on the structure formation of membranes and their permeation properties connected with the changes in thermodynamic and kinetic properties in the phase inversion process. The membranes were prepared by using polyetherimide/-methyl-2-pyrrolidone/PEG (PEI/NMP/PEG) casting solution and water coagulant. The resulting membranes, prepared by changing the ratio of PEG to PEI, were characterized by scanning electron microscope (SEM) observations, measurements of water flux and -globin rejection. The thermodynamic and kinetic properties of the membrane-forming system were studied through viscosity. The pore radius distribution curves were especially obtained by differential scanning calorimetry (DSC). Furthermore, the membranes were characterized for pure water flux and rejection of solute and by SEM observation. The filtration results agreed well with the SEM observations. As expected, PEG with a fixed molecular weight (PEG 600) acted as a pore forming agent, and membrane porosity increased as the PEG content of the casting solution increased.

关键词： permeation     ethylene     filtration     PEI/NMP/PEG     membrane    

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Grafting of PEG400 onto the surface of LLDPE/SMA film

CHEN Gufeng, ZHANG Yi, XU Jiarui, ZHU Yafei

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 128-131 doi: 10.1007/s11705-007-0024-6

摘要： Linear low-density polyethylene (LLDPE) was melt and blended with styrene-maleic anhydride copolymer (SMA). The blending films were then immersed in poly(ethylene glycol)400 (PEG400) at room temperature. The surface composition of the blend films was determined by Fourier transform infra-red spectroscopy coupled with a variable incidence angle attenuated total reflection accessory (ATR-FTIR). Results show that PEG400 can be grafted onto the surface of the films via esterification with SMA. The immersion of PEG promotes the enrichment of SMA onto the surface of the films. The water contact angle data show that grafting of PEG400 onto PE can greatly improve the hydrophilicity of the PE surface. These experiments show that surface functionalization of polyethylene films by blending SMA and then surface grafting of PEG is feasible, which suggest an effective and simple route for PE surface modification via blending and grafting.

关键词： hydrophilicity     temperature     effective     immersion     reflection accessory    

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Thin-film composite forward osmosis membranes with substrate layer composed of polysulfone blended with PEGor polysulfone grafted PEG methyl ether methacrylate

Baicang Liu,Chen Chen,Pingju Zhao,Tong Li,Caihong Liu,Qingyuan Wang,Yongsheng Chen,John Crittenden

《化学科学与工程前沿（英文）》 2016年 第10卷 第4期   页码 562-574 doi: 10.1007/s11705-016-1588-9

摘要： To advance commercial application of forward osmosis (FO), we investigated the effects of two additives on the performance of polysulfone (PSf) based FO membranes: one is poly(ethylene glycol) (PEG), and another is PSf grafted with PEG methyl ether methacrylate (PSf-g-PEGMA). PSf blended with PEG or PSf-g-PEGMA was used to form a substrate layer, and then polyamide was formed on a support layer by interfacial polymerization. In this study, NaCl (1 mol?L ) and deionized water were used as the draw solution and the feed solution, respectively. With the increase of PEG content from 0 to 15 wt-%, FO water flux declined by 23.4% to 59.3% compared to a PSf TFC FO membrane. With the increase of PSf-g-PEGMA from 0 to 15 wt-%, the membrane flux showed almost no change at first and then declined by about 52.0% and 50.4%. The PSf with 5 wt-% PSf-g-PEGMA FO membrane showed a higher pure water flux of 8.74 L?m ?h than the commercial HTI membranes (6–8 L?m ?h ) under the FO mode. Our study suggests that hydrophobic interface is very important for the formation of polyamide, and a small amount of PSf-g-PEGMA can maintain a good condition for the formation of polyamide and reduce internal concentration polarization.

关键词： thin-film composite     forward osmosis     amphiphilic copolymer     interfacial polymerization     poly(ethylene glycol)    

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Synthesis and characterization of macromolecular surface modifier PP--PEG for polypropylene

CHEN Hanjia, SHI Xuhua, ZHU Yafei, ZHANG Yi, XU Jiarui

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 102-108 doi: 10.1007/s11705-008-0018-z

摘要： A novel macromolecular surface modifier, polypropylene-grafted-poly(ethylene glycol) copolymer (PP--PEG), was synthesized by coupling polypropylene containing maleic anhydride with monohydroxyl-terminated poly(ethylene glycol). The effects of the reaction condition on the graft reactions were studied. The copolymers were characterized by IR, H NMR, thermogravimetry (TG) and differential scanning calorimetry (DSC). The results indicated that the graft reactions were hindered by increasing the molecular weight of PP or PEG. The graft copolymer was found to have a higher initial thermal degradation temperature and lower crystallization capacity as compared with pure PP, and the side chain of PEG hindered the PP chain from forming a perfect ? crystal. The thermal stability of PP--PEG decreased with the increasing content or molecular weight of PEG. The copolymers were blended with polypropylene to modify the surface hydrophilicity of the products. The results of attenuated total reflectance FTIR spectroscopy (ATR-FTIR) showed that PP--PEG could diffuse preferably onto the surface of the blends and be suitable as an effectual macromolecular surface modifier for PP.

关键词： polypropylene     crystallization capacity     attenuated     hydrophilicity     reflectance    

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Preparation and properties of gel membrane containing porous PVDF-HFP matrix and cross-linked PEG for

ZHANG Mei, CUI Zhenyu, ZHU Baoku, HAN Gaige, XU Youyi, ZHANG Aiqing

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 89-94 doi: 10.1007/s11705-008-0011-6

摘要： Lithium ion conducting membranes are the key materials for lithium batteries. The lithium ion conducting gel polymer electrolyte membrane (Li-GPEM) based on porous poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) matrix and cross-linked PEG network is prepared by a typical phase inversion process. By immersing the porous PVDF-HFP membrane in liquid electrolyte containing poly(ethylene glycol) diacrylate (PEGDA) and an initiator to absorb the liquid electrolyte at 25°C, and then thermally cross-linking at 60°C, the Li-GPEM is fabricated successfully. The measurements on its weight loss, mechanical and electrochemical properties reveal that the obtained Li-GPEM has better overall performance than the liquid and blend gel systems used as conductive media in lithium batteries. The ionic conductivity of the fabricated Li-GPEM can reach as high as 2.25 × 10 S/cm at 25°C.

关键词： ethylene     PEGDA     inversion     network     initiator    

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Effect of incorporating Elaeagnus angustifolia extract in PCL-PEG-PCL nanofibers for bone tissue engineering

Vahideh R. Hokmabad, Soodabeh Davaran, Marziyeh Aghazadeh, Effat Alizadeh, Roya Salehi, Ali Ramazani

《化学科学与工程前沿（英文）》 2019年 第13卷 第1期   页码 108-119 doi: 10.1007/s11705-018-1742-7

摘要：

Plants have been used for medicinal purposes for thousands of years but they are still finding new uses in modern times. For example, Elaeagnus angustifolia (EA) is a medicinal herb with antinociceptive, anti-inflammatory, antibacterial and antioxidant properties and it is widely used in the treatment of rheumatoid arthritis and osteoarthritis. EA extract was loaded onto poly(ϵ-caprolactone)-poly(ethylene glycol)-poly(ϵ-caprolactone) (PCL-PEG-PCL/EA) nanofibers and their potential applications for bone tissue engineering were studied. The morphology and chemical properties of the fibers were evaluated using Fourier transform infrared spectroscopy, field emission scanning electron microscopy, contact angle measurements and mechanical tests. All the samples had bead-free morphologies with average diameters ranging from 100 to 200 nm. The response of human cells to the PCL-PEG-PCL/EA nanofibers was evaluated using human dental pulp stem cells (hDPSCs). The hDPSCs had better adhesion and proliferation capacity on the EA loaded nanofibers than on the pristine PCL-PEG-PCL nanofibers. An alizarin red S assay and the alkaline phosphatase activity confirmed that the nanofibrous scaffolds induced osteoblastic performance in the hDPSCs. The quantitative real time polymerase chain reaction results confirmed that the EA loaded nanofibrous scaffolds had significantly upregulated gene expression correlating to osteogenic differentiation. These results suggest that PCL-PEG-PCL/EA nanofibers might have potential applications for bone tissue engineering.

关键词： Elaeagnus angustifolia     scaffold     electrospinning     human dental pulp stem cell     tissue engineering    

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Control on self-assembly structures of rod-coil-rod (PANI)-(PEG)-(PANI) triblock copolymer

YANG Zhifang, WU Jingao, YANG Yingkui, ZHOU Xingping, XIE Xiaolin

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 85-88 doi: 10.1007/s11705-008-0003-6

摘要： The self-assembly behaviors of the rod-coil-rod (PANI)-(PEG)-(PANI) triblock copolymer are investigated in different solvents, such as -methyl-2-pyrrolidone (NMP), dimethyl formamide (DMF), ethanol and water. The effects of solvents, concentration and ultrasonic irradiation on self-assembly are discussed. The results indicate that the triblock copolymer forms particles, rods, fiber, networks and fiber bands in the above solvents, respectively. Especially, the triblock copolymer can form a multi-layer, tri-dimensional fibrous network and a petaline structure from the mono-layer fibrous network with the increase of its concentration in ethanol. Also, the ultrasonic irradiation has a great effect on the self-assembly of the triblock copolymer.

关键词： different     multi-layer     mono-layer     dimethyl formamide     concentration    

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Hydrogen production by catalytic gasification of cellulose in supercritical water

GUAN Yu, PEI Aixia, GUO Liejin

《化学科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 176-180 doi: 10.1007/s11705-008-0026-z

摘要： Cellulose, one of the important components of biomass, was gasified in supercritical water to produce hydrogen-rich gas in an autoclave which was operated batch-wise under high-pressure. KCO and Ca(OH) were selected as the catalysts (or promoters). The temperature was kept between 450°C and 500°C while pressure was maintained at 24–26 MPa. The reaction time was 20 min. Experimental results showed that the two catalysts had good catalytic effect and optimum amounts were observed for each catalyst. When 0.2 g KCO was added, the hydrogen yield could reach 9.456 molkg which was two times of the H amount produced without catalyst. When 1.6 g Ca(OH) was added, the H yield was 8.265 molkg which is lower than that obtained using KCO as catalyst but is still 1.7 times that achieved without catalyst. Comparing with the results obtained using KCO or Ca(OH) alone, the use of a combination of KCO and Ca(OH) could increase the H yield by up to 2.5 times that without catalyst and 25% and 45% more than that obtained using KCO and Ca(OH) alone, respectively. It was found that methane was the dominant product at relatively low temperature. When the temperature was increased, the methane reacts with water and is converted to hydrogen and carbon dioxide.

关键词： reaction     temperature     combination     catalytic effect     dominant product    

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A visual graphic approach for mobility analysis of parallel mechanisms

Xu PEI, Jingjun YU

《机械工程前沿（英文）》 2011年 第6卷 第1期   页码 92-95 doi: 10.1007/s11465-011-0213-3

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A compound load simulator based on zero-torsion parallel mechanisms

Jingjun YU, Wei LI, Xu PEI, Shusheng BI, Guanghua ZONG

《机械工程前沿（英文）》 2012年 第7卷 第1期   页码 1-4 doi: 10.1007/s11465-012-0306-7

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CFD simulation of jet behaviors in a binary gas-solid fluidized bed: comparisons with experiments

Pei PEI, Guiying WU, Bangting YU, Kai ZHANG, Jianchun JIANG, Dongsheng WEN,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 242-249 doi: 10.1007/s11705-009-0277-3

摘要： Based on the experimental observation of the fluidization characteristics of solid mixtures (resin and rapeseed) with different densities and sizes, the jet behaviours of the binary system are simulated in a two-dimensional jetting fluidized bed 0.30 m in width and 2.00 m in height. A simple mathematical model, by introducing two additional force terms in both gas and particle phase momentum equations of Gidaspow’s inviscid two-fluid model, is used to explore the effects of jet gas velocity and mixture combination on the jet penetration depth in the fluidized bed with a binary system. Experimental results show that there is a fluidization velocity interval (-) for the resin-on-rapeseed (flotsam-on-jetsam) segregated bed. The simulated jet penetration depth increases with the increase of jet gas velocity and the volume fraction of the flotsam (resin), which is in fair agreement with experimental data. The above findings show that the hydrodynamic model of Brandani and Zhang (2006), by introducing the average physical properties from Goossens et al.(1971), can be used to predict the jet behaviors of a well-mixing binary system.

关键词： mathematical     two-dimensional     flotsam-on-jetsam     fluidization velocity     physical    

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Performance analysis of an air-source heat pump using an immersed water condenser

Jie JI, Huide FU, Hanfeng HE, Gang PEI,

《能源前沿（英文）》 2010年 第4卷 第2期   页码 234-245 doi: 10.1007/s11708-009-0056-3

摘要： A distributed model of an air-source heat pump (ASHP) system and its experimental setup using an immersed water condenser were presented. Dynamic performance of the ASHP was then evaluated by both simulation and experiment. The results indicated that the system coefficient of performance (COP) decreased as the condenser temperature increased, ranging from 4.41 to 2.32 with the average COP equaling 3.29 during the experiment. Comparisons between simulation results and experimental measurements demonstrated that the model was able to yield satisfactory predictions. Furthermore, temperature profiles of the refrigerant in the evaporator and condenser were also given. This paper provides the theoretical and experimental background for ASHP system optimization and a valuable reference for a solar air-source heat pump water heater when the solar irradiation energy is insufficient on cloudy or rainy days.

关键词： air-source     heat pump     distributed model     immersed water condenser    

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Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene carbonate under mild conditions

Rui YAO, Hua WANG, Jinyu HAN

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 239-245 doi: 10.1007/s11705-012-1297-y

摘要： The coupling reaction of propylene and CO to form propylene carbonate (PC) was promoted by an ionic liquid (IL) covalently bound to polyethylene glycol (PEG). The supported ionic liquid, which has both acidic and basic components, proved to be an active catalyst for PC synthesis under mild conditions. The effects of different cations and anions, reaction temperature, CO pressure, and reaction time were investigated. It was demonstrated that the acid group in the catalyst plays an important role in the reaction. With this system, a high PC yield (95%) was achieved under mild conditions (3.0 MPa, 120°C and 4 h) without a co-solvent. In addition, the catalyst was readily recovered and reused. Based on the experimental results, a plausible mechanism for the catalyst was proposed.

关键词： ionic liquid     PEG-supported ionic liquid     carbon dioxide     propylene carbonate    

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Chemical characteristics of fine particulate matter emitted from commercial cooking

Bing PEI,Hongyang CUI,Huan LIU,Naiqiang YAN

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 559-568 doi: 10.1007/s11783-016-0829-y

摘要： The chemical characteristics of fine particulate matter (PM ) emitted from commercial cooking were explored in this study. Three typical commercial restaurants in Shanghai, i.e., a Shanghai-style one (SHS), a Sichuan-style one (SCS) and an Italian-style one (ITS), were selected to conduct PM sampling. Particulate organic matter (POM) was found to be the predominant contributor to cooking-related PM mass in all the tested restaurants, with a proportion of 69.1% to 77.1%. Specifically, 80 trace organic compounds were identified and quantified by gas chromatography/mass spectrometry (GC/MS), which accounted for 3.8%–6.5% of the total PM mass. Among the quantified organic compounds, unsaturated fatty acids had the highest concentration, followed by saturated fatty acids. Comparatively, the impacts of other kinds of organic compounds were much smaller. Oleic acid was the most abundant single species in both SCS and ITS. However, in the case of SHS, linoleic acid was the richest one. ITS produced a much larger mass fraction of most organic species in POM than the two Chinese cooking styles except for monosaccharide anhydrides and sterols. The results of this study could be utilized to explore the contribution of cooking emissions to PM pollution and to develop the emission inventory of PM from cooking, which could then help the policy-makers design efficient treatment measures and control strategies on cooking emissions in the future.

关键词： commercial cooking     PM2.5     chemical characteristics     organic matter    

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Effect of inhibiting tyrosine kinase Src expression on protein phosphatase 2A and tau phosphorylation

LIU Rong, ZENG Ji, ZHOU Xinwen, WANG Jianzhi, PEI Jinjing

《医学前沿（英文）》 2008年 第2卷 第3期   页码 235-238 doi: 10.1007/s11684-008-0044-8

摘要： The aim of this study is to investigate the effect of tyrosine kinase Src on Tyrosine 307(Y307) phosphorylation, protein phosphatase 2A (PP2A) activity, and on tau phosphorylation. Specific Src siRNA was transfected into cultured mouse neuroblastoma N2a cells to inhibit the expression of Src protein, and the phosphorylation levels of PP2A Y307 and tau at different sites, as well as PP2A activity were detected at different time points after siRNA transfection. Twelve hours after siRNA transfection, the protein level of Src was dramatically decreased, with decreased PP2A Y307 phosphorylation. However, the total PP2A protein level was also decreased, together with a decreased PP2A activity. Tau was hyperphosphorylated at the Ser198/199/202 sites. Multiple factors may be involved in the cellular regulation of PP2A activity. Inhibiting Src expression could induce inactivation of PP2A and tau hyperphosphorylation.

关键词： hyperphosphorylation     PP2A activity     cellular regulation     siRNA     siRNA transfection    

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标题 作者 时间 类型 操作

Effect of PEG additives on properties and morphologies of polyetherimide membranes prepared by phase

Jian CHEN, Jiding LI, Xia ZHAN, Xiaolong HAN, Cuixian CHEN,

期刊论文

Grafting of PEG400 onto the surface of LLDPE/SMA film

CHEN Gufeng, ZHANG Yi, XU Jiarui, ZHU Yafei

期刊论文

Thin-film composite forward osmosis membranes with substrate layer composed of polysulfone blended with PEGor polysulfone grafted PEG methyl ether methacrylate

Baicang Liu,Chen Chen,Pingju Zhao,Tong Li,Caihong Liu,Qingyuan Wang,Yongsheng Chen,John Crittenden

期刊论文

Synthesis and characterization of macromolecular surface modifier PP--PEG for polypropylene

CHEN Hanjia, SHI Xuhua, ZHU Yafei, ZHANG Yi, XU Jiarui

期刊论文

Preparation and properties of gel membrane containing porous PVDF-HFP matrix and cross-linked PEG for

ZHANG Mei, CUI Zhenyu, ZHU Baoku, HAN Gaige, XU Youyi, ZHANG Aiqing

期刊论文

Effect of incorporating Elaeagnus angustifolia extract in PCL-PEG-PCL nanofibers for bone tissue engineering

Vahideh R. Hokmabad, Soodabeh Davaran, Marziyeh Aghazadeh, Effat Alizadeh, Roya Salehi, Ali Ramazani

期刊论文

Control on self-assembly structures of rod-coil-rod (PANI)-(PEG)-(PANI) triblock copolymer

YANG Zhifang, WU Jingao, YANG Yingkui, ZHOU Xingping, XIE Xiaolin

期刊论文

Hydrogen production by catalytic gasification of cellulose in supercritical water

GUAN Yu, PEI Aixia, GUO Liejin

期刊论文

A visual graphic approach for mobility analysis of parallel mechanisms

Xu PEI, Jingjun YU

期刊论文

A compound load simulator based on zero-torsion parallel mechanisms

Jingjun YU, Wei LI, Xu PEI, Shusheng BI, Guanghua ZONG

期刊论文

CFD simulation of jet behaviors in a binary gas-solid fluidized bed: comparisons with experiments

Pei PEI, Guiying WU, Bangting YU, Kai ZHANG, Jianchun JIANG, Dongsheng WEN,

期刊论文

Performance analysis of an air-source heat pump using an immersed water condenser

Jie JI, Huide FU, Hanfeng HE, Gang PEI,

期刊论文

Polyethylene glycol-supported ionic liquid as a highly efficient catalyst for the synthesis of propylene carbonate under mild conditions

Rui YAO, Hua WANG, Jinyu HAN

期刊论文

Chemical characteristics of fine particulate matter emitted from commercial cooking

Bing PEI,Hongyang CUI,Huan LIU,Naiqiang YAN

期刊论文

Effect of inhibiting tyrosine kinase Src expression on protein phosphatase 2A and tau phosphorylation

LIU Rong, ZENG Ji, ZHOU Xinwen, WANG Jianzhi, PEI Jinjing

期刊论文