JOURNAL OF MOLECULAR RECOGNITION
·
2016
·Vol. 30
·期 1
·e2566
·
IF 2.091
Hua-jin Zeng,Min Miao,Ran Yang,Ling-bo Qu
In this study, the fibrillation of hen egg-white lysozyme (HEWL) in the absence and presence of different concentrations of silybin was studied by thioflavin T spectroscopy, Congo red binding assays, 8-anilino-1-naphthalenesulfonic acid (ANS) fluorescence assay, circular dichroism, and transmission electron microscopy. The experimental results indicated that not only the fibrillation of HEWL at high temperature (65°C) and low pH (pH = 2.0) could be inhibited effectively by silybin but also the inhibition of HEWL by silybin followed a dose-dependent manner. Molecular docking studies indicated that 2 possible binding modes could be found in the interaction between silybin and HEWL via van der Waals forces and electrostatic forces as well as hydrogen bonding. One of these 2 conformations was directly entered into the cavity of HEWL (binding site I); the other was bound to the surface of HEWL (binding site II). In this way, silybin could not only increase the hydrophobicity of the cavity or the surface of HEWL but also influence the microenvironment of the binding site, which was able to stabilize the structure of HEWL and delay the process of HEWL fibrosis.
研究领域:
生物化学
·
分子生物学
·
蛋白质科学
·
药理学
·
结构生物学
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 29
·45093
·
IF 1.86
Jianning Wu,Baoxun Sui,Lei Li,Guihua Meng,Xuhong Guo,Zhiyong Liu
A higher porosity with better thermostability is desirable for poly(vinyl chloride) (PVC) resin. In this study, high molecular weight PVC resins are prepared by vinyl chloride monomer (VCM)-diallyl phthalate (DAP) suspension copolymerization in a 20-L reactor at 50 °C using DAP as chain extender. SEM, BET, and analyses of plasticizer absorption results show the high molecular weight poly(vinyl chloride) (HPVC) by DAP-VCM copolymerization is loose and porous. With increasing DAP content when the mass ratio of DAP/VCM (ω ) is below the gel point, the porosity and the degree of polymerization increase. Nevertheless, the bulk density and particle size decrease. When more than the gel point, these relationships are reversed. Thermogravimetric analysis revealed that the HPVC had better thermostability than that of commercial PVC, and its thermostability increases with increasing ω before it reaches the gel point. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45093.
研究领域:
高分子化学
·
材料科学
·
聚合物合成
·
热分析
·
多孔材料
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DOI
高影响因子
POLYMER TESTING
·
2022
·
IF 4.931
Ying Chen,Jie Li,Jiawei Lu,Meng Ding,Yi Chen
PVA hydrogels with high strength and toughness are fabricated by dual physical and chemical cross-linking. The best comprehensive mechanical properties can be achieved by reaction at room temperature followed with freeze-thaw and annealing treatment. Besides, the mechanical properties of PVA hydrogel increased first and then decreased with the increase of molecular weight or mass fraction. By changing the reaction solvent, the mechanical properties of PVA hydrogel could also be effectively adjusted. Therefore, the influences of various factors on the mechanical properties of PVA hydrogel can be obtained.
研究领域:
生物材料
·
高分子科学
·
组织工程
·
生物医学工程
·
软物质物理
·
药物递送系统
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DOI
高影响因子
MONATSHEFTE FUR CHEMIE
·
2014
·Vol. 146
·期 3
·441-447
·
IF 1.347
Li Longfei,Chen Lin,Liu Weifeng,Yang Yongzhen,Liu Xuguang,Chen Yongkang
5-Fluorouracil surface-imprinted thermosensitive magnetic microspheres were prepared by using Fe 3 O 4 -encapsulating carbon microspheres as cores, N -isopropylacrylamide as thermosentitive monomer, ammonium persulfate as initiator, N , N ′-methylenebisacrylamide as crosslinker, and 5-fluorouracil as template molecule. The formation of these hybrid microspheres was verified by field emission scanning electron microscopy, transmission electron microscopy, Fourier transformation infrared spectroscopy, thermogravimetry, and dynamic light scattering. The results of the latter measurements show that the as-synthesized microspheres have a hydrodynamic diameter of 326 nm with the lower critical solution temperature of around 43 °C. The obtained microspheres are magnetic and show good potential for controlled loading and release of 5-fluorouracil. Graphical abstract
研究领域:
药剂学
·
纳米医学
·
肿瘤治疗
·
高分子材料科学
·
靶向给药系统
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DOI
高影响因子
MARINE POLLUTION BULLETIN
·
2015
·Vol. 102
·期 1
·142-147
·
IF 2.991
Xiuping He,Xiaoqi Mei,Jiangtao Wang,Ziru Lian,Liju Tan,Wei Wu
An effective and highly selective molecularly imprinted material was prepared by suspension polymerization for the isolation and pre-concentration of synthetic estrogen diethylstilbestrol (DES) in seawater . The obtained MIPMs were proved to have more uniform size and porous structure, with maximum adsorption capacity of 8.43 mg g − 1 almost two times more than NIPMs (4.43 mg g − 1 ). The MIPMs showed no significant deterioration of the adsorption capacity after five rounds of regeneration. An off-line molecularly imprinted solid phase extraction (MISPE) method followed by HPLC–DAD was proposed for the detection of DES in seawater , and recoveries were satisfactorily higher than 77%. Four seawater samples in aquaculture area were analyzed and 0.61 ng mL − 1 DES was detected in one sample. The result demonstrated that this method can be used for the rapid separation and clean up of trace residual of DES in seawater.
研究领域:
环境分析化学
·
海洋环境污染
·
分子印迹技术
·
药物残留检测
·
水体污染物
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DOI
高影响因子
POLYMER
·
2018
·
IF 3.483
Haofei Li,Hongbo Wang,Dongfei Zhang,Ziyang Xu,Wenguang Liu
Recently, we have constructed a high strength and thermoplastic supramolecular poly( N -acryloyl glycinamide) (PNAGA) hydrogel which can be developed as printable bioinks. However, the PNAGA hydrogel is low in stiffness and toughness, potentially limiting its application as load-bearing soft tissue scaffolds. In this work, we fabricate a supramolecular polymer double-network hydrogel based on hydrogen bonding crosslinked PNAGA and Fe 3+ -coordination crosslinked sodium carboxymethyl cellulose (CMC). The combined hydrogen bonding and ionic crosslinks contribute to high-strength nonswellable PNAGA/CMC-Fe hydrogels (Tensile strength of 2.9 MPa and compressive strength of 7.3 MPa at 80% strain without fracture) and stiffness (Young's modulus of 1.2 MPa and compressive modulus of 1.5 MPa). Furthermore, these reversible double physical crosslinks enable the PNAGA/CMC-Fe hydrogels to dissipate energy efficiently with a high toughness (12.3 MJ m −3 ) and tear energy (3700 J m −2 ), meanwhile imparting self-recoverability, anti-fatigue ability and self-healability to the network. This cytocompatible supramolecular polymer double network hydrogel with excellent multifaceted mechanical performances are promising to exploited as load-bearing soft tissue engineering scaffolds .
研究领域:
生物材料学
·
组织工程
·
高分子科学
·
再生医学
·
生物力学
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DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2015
·Vol. 36
·期 10
·1726-1732
·
IF 1.964
Huanhui Chen,Xiaoci Li,Guoqing Zhao,Hongbo Gu,Zhirong Zhu
The side-chain alkylation of toluene represents a novel, environmentally friendly, and low cost route for the production of styrene . However, the yield of styrene produced in this way is currently low, and the mechanism responsible for the side-chain alkylation of toluene is poorly understood. Furthermore, the reason for the higher catalytic efficiency of CsX over NaX and KX remains unclear. In this work, the free radical mechanism of the side-chain alkylation of toluene over basic zeolite X has been elucidated using quantum chemical calculations , together with isotope tracing experiments and the reaction between p -nitrotoluene and methanol. The adsorption isotherm of methanol showed that Cs + ions could block methanol from accessing the β-cage, which is where the side-chain alkylation reaction occurred. Furthermore, the H–D exchange results between toluene and deuterated toluene (C 6 D 5 CD 3 ) showed that CsX was more efficient as a catalyst than KX for the conversion of toluene to the corresponding benzyl radical (C 6 H 5 CH 2 • ). These two results therefore explain the higher catalytic activity of CsX towards side-chain alkylation than KX. Based on the free radical mechanism, the selectivity of styrene could be increased from 17.4% to 59.4% using CO 2 as carrier gas instead of N 2 .
研究领域:
物理化学
·
催化化学
·
材料化学
·
反应机理
·
理论化学
·
能源化学
·
环境化学
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DOI
高影响因子
MATERIALS & DESIGN
·
2015
·
IF 3.501
Heng Zhang,Libo Wang,Qiang Chen,Ping Li,Aiguo Zhou,Xinxin Cao,Qianku Hu
In this study, a Ti 3 C 2 nanomaterial and Ti 3 C 2 /UHMWPE (ultrahigh molecular weight polyethylene) nanocomposites were prepared. The morphology, structure and properties of the Ti 3 C 2 /UHMWPE nanocomposites were investigated. The results indicate that Ti 3 C 2 nanoparticle can improve the thermal and mechanical properties of UHMWPE . The crystallinity and hardness of the Ti 3 C 2 /UHMWPE nanocomposite increase with the content of Ti 3 C 2 . The tensile and breaking strengths of the nanocomposites are enhanced with increasing Ti 3 C 2 content and reach maximum values at a mass fraction of 0.75 wt.%. The creep performance is enhanced after the addition of Ti 3 C 2 to the matrix. The frictional properties of the Ti 3 C 2 /UHMWPE composites were investigated using a pin-on-disc tester. The Ti 3 C 2 /UHMWPE composites exhibited a better friction-reducing performance compared with pure UHMWPE . The addition of Ti 3 C 2 can reduce the adhesive wear and plow friction, which results in the worn surfaces of the Ti 3 C 2 /UHMWPE composite being smoother than those of pure UHMWPE.
研究领域:
材料科学
·
高分子材料
·
摩擦学
·
纳米复合材料
·
机械工程
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2016
·
IF 3.12
Huali Xie,Xuejun Lai,Hongqiang Li,Xingrong Zeng
Fabricating an effective synergism between the condensed phase (char-forming) and the gas phase (free-radical quenching) is recently considered to be a very promising way to prepare high-efficient intumescent flame retardants . In this work, a novel hindered amine phosphorous-nitrogen macromolecular charring agent (HAPN) with free-radical quenching capability was synthesized and characterized. Then it was combined with ammonium polyphosphate (APP) to flame-retard polypropylene (PP). The flame retardancy and thermal stability of PP/HAPN/APP mixtures were investigated by limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetric test (CCT) and thermogravimetric analysis (TGA). When the content of HAPN/APP was 25 wt%, PP/HAPN/APP could self-extinguish at 36 s after igniting in the oxygen concentration of 29.5% and achieve a UL-94 V-0 rating. Meanwhile, the peak heat release rate (PHRR), total heat release rate (THR), average heat release rate (AV-HRR) and average mass loss rate (AV-MLR) were significantly decreased. The flame retardant mechanism of HAPN/APP was explored and the results revealed that there was an effective synergism between the condensed phase and the gas phase during the combustion. In the condensed phase, HAPN could make PP involve into the char-forming reaction to promote the formation of compact and firm intumescent char layer. Simultaneously, the nitroxyl radical generated by HAPN could effectively restrain and even extinguish the flame in the gas phase by quenching the active free-radicals.
研究领域:
高分子化学
·
材料科学
·
阻燃材料
·
热稳定性
·
燃烧性能
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 19
·11701-11714
·
IF 2.599
Wei Xiuzhen,Hong Jialiang,Zhu Shuangshuang,Chen Jinyuan,Lv Bosheng
Polyethyleneimine (PEI) of various molecular weights and trimesoyl chloride (TMC) were utilized to prepare composite nanofiltration (NF) membranes via interfacial polymerization. The changes in the surface structure and chemical composition of the prepared membranes were evaluated using SEM, ATR-FTIR, XPS and surface potential measurements. The pure-water flux and rejection rates of the inorganic salts (MgCl 2 , MgSO 4 , Na 2 SO 4 and NaCl) through the resultant NF membranes were also investigated. The results showed that the performance of the composite NF membranes was significantly affected by the molecular weight of the PEI. Notably, the permeate flux and rejection rate of the NF membranes increased with the PEI molecular weight. In addition, when the NF membranes were used to treat actual wastewater from the electroplating industry, the NF membranes presented high-efficiency separation properties for heavy metal ions. The rejection rates of the NF membranes at 0.4 MPa for chromium, nickel, zinc and copper ions reached 92.6, 89.6, 89.2 and 86.3%, respectively.
研究领域:
材料科学
·
膜分离技术
·
环境工程
·
高分子化学
·
水处理
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DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2018
·
IF 3.485
Xiong Xu,Jianying Yu,Lihui Xue,Bianyang He,Wei Du,Huang Zhang,Ying Li
The excellent comprehensive performance of SBS modified bitumen (SMB), during a long-term thermo- and photo-oxidative exposure, will fail to satisfy the pavement requirement. In this paper, the synergistic effect of 4,4′-diphenylmethane diisocyanate (MDI) and 1,4-butanediol diglycidyl ether (BUDGE) on the molecular weight of aged SBS was firstly studied, through a simulation, to confirm whether a new polymer structure can be obtained. Then, the reactive rejuvenating system containing MDI, BUDGE and bituminous composition returning agent (MDI-BUDGEs) was applied in the rejuvenation of aged SMB. The results show that the rebuilt molecular structure of aged SBS can be obtained with the combination of MDI and BUDGE. Meanwhile, MDI-BUDGEs can improve the low-temperature ductility and inhibit the sharp fall of the softening point of aged SMB, while decrease the viscosity-temperature response at 120–165 °C. Also, MDI-BUDGEs can contribute for increasing the viscous component, improving the fatigue resistance and remaining the high-temperature performance grade of aged SMB, and moreover, decrease the limited elastic modulus and the elastic-plasticity transition rate to avoid the occurrence of the brittle failure within a small strain range.
研究领域:
道路工程材料
·
高分子材料老化与修复
·
沥青化学
·
流变学
·
建筑材料耐久性
✓ 已验证
DOI
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2016
·
IF 3.42
Jing Li,Sanming Li,Zhonggui He
In the present work, molecular imprinting silica xerogel (MISX) with selective recognition function aiming to regulate drug therapy was synthesized using biomimetic method with poly(ethyleneimine)s (PEIs) as the polymer template and levorotatory ofloxacin (LOFL) as recognition template. Ultraviolet spectroscopy wavelength scanning was used to test the removal process of LOFL, and characteristics of selective loading ofloxacin (OFL) into MISX were investigated using Fourier transform infrared spectroscopy (FT-IR) and differential scanning calorimetry (DSC). Molecular recognition functionality of MISX was intensively studied, including OFL loading and release. The results suggested that MISX possessed ability to recognize and selectively adsorb LOFL into MISX in OFL aqueous solution. Amorphous phase of adsorbed molecules contributed to molecular recognition because amorphous state increased the stability of LOFL that were selectively adsorbed into MISX, which induced stronger hydrogen bonding formed between LOFL and MISX so as to improve LOFL recognition ability. In vitro release revealed that OFL-MISX tablet initially released LOFL and later gradually OFL into dissolution medium. Thus conversion of drug release with different pharmacological activity had special value in delivering systems.
研究领域:
药剂学
·
药物化学
·
纳米医学
·
生物材料
·
分子识别
·
药物递送系统
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）