Rational design of artificial dye-decolorizing peroxidases using myoglobin by engineering Tyr/Trp in the heme center
作者：
Li, Le-Le;Yuan, Hong;Liao, Fei;He, Bo;Gao, Shu-Qin;...
期刊：
DALTON TRANSACTIONS ,2017年46(34):11230-11238 ISSN：1477-9226
通讯作者：
Lin, Ying-Wu
作者机构：
[Liao, Fei; Li, Le-Le; Lin, Ying-Wu; He, Bo] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Yuan, Hong; Tan, Xiangshi] Fudan Univ, Dept Chem, Shanghai 200433, Peoples R China.;[Yuan, Hong; Tan, Xiangshi] Fudan Univ, Inst Biomed Sci, Shanghai 200433, Peoples R China.;[Gao, Shu-Qin; Wen, Ge-Bo; Lin, Ying-Wu] Univ South China, Lab Prot Struct & Funct, Hengyang 421001, Peoples R China.
通讯机构：
[Lin, Ying-Wu] U;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;Univ South China, Lab Prot Struct & Funct, Hengyang 421001, Peoples R China.
摘要：
The rational design of metalloenzymes provides advantages not only for illustrating the structure and function relationship of native enzymes, but also for creating functional artificial enzymes comparable to native enzymes. Dye-decolorizing peroxidases (DyPs) are a new family of heme peroxidases and have received much attention recently. Inspired by the structural features of native DyPs with multiple Tyr and Trp residues, we herein aimed to design functional artificial DyPs using myoglobin (Mb), an O2 carrier as a protein scaffold, by further introduction of Tyr/Trp into the secondary sphere of the heme center in the F43Y Mb mutant. The latter has been shown to possess a novel Tyr-heme cross-link and exhibit enhanced peroxidase activity, which provides an ideal platform to design a series of derivatives, including F43Y/F46Y Mb, F43Y/I107Y Mb, F43Y/F138 W Mb and F43Y/I107Y/F138 W Mb. Our design revealed that the Tyr-heme cross-link was well-retained in the mutants except for F43Y/F46Y Mb, as confirmed by X-ray crystal structure analysis. More importantly, stopped-flow kinetic studies showed that these derivatives exhibit enhanced dye-decolorizing peroxidase activities compared to that of wild-type (WT) Mb. This is particularly the case for the double mutant F43Y/F138 W Mb, exhibiting an overall catalytic efficiency (kcat/Km) of 110670 M-1 s-1, which is ∼144-fold and ∼20-fold that of WT Mb and F43Y Mb, respectively, and is ∼4.3-fold that of native DyP from Vibrio cholerae. Stopped-flow, electron paramagnetic resonance (EPR) and isothermal titration calorimetry (ITC) studies further provided insights into the activation of H2O2 and the binding of a substrate, reactive blue 19 (RB19), to the double mutant. This study provides valuable information for elucidating the structure and dye-decolorizing function relationship of peroxidases, and also clues for the design of other functional artificial heme enzymes. © 2017 The Royal Society of Chemistry.
语种：
英文
展开
Stabilization of cytochrome b5 by a conserved tyrosine in the secondary sphere of heme active site: A spectroscopic and computational study
作者：
Hu, Shan;He, Bo;Wang, Xiao-Juan;Gao, Shu-Qin;Wen, Ge-Bo;...
期刊：
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY ,2017年174:118-123 ISSN：1386-1425
通讯作者：
Lin, Ying-Wu
作者机构：
[Lin, Ying-Wu; Wang, Xiao-Juan; Hu, Shan; He, Bo] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Gao, Shu-Qin; Wen, Ge-Bo; Lin, Ying-Wu] Univ South China, Lab Prot Struct & Funct, Hengyang 421001, Peoples R China.
通讯机构：
[Lin, Ying-Wu] U;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.
关键词：
Heme proteins;Cyt b(5);Secondary sphere;Unfolding;Heme transfer
摘要：
Heme proteins perform a large array of biological functions, with the heme group bound non-covalently or covalently. To probe the stabilization role of conserved tyrosine residue in the secondary sphere of heme site in heme proteins, we herein used cytochrome b(5) (Cyt b(5)) as a model protein, and mutated Tyr30 to Phe or His by removal of Tyr30 associated H-bond network and hydrophobic interaction. We performed thermal-induced unfolding studies for the two mutants, Y30F Cyt b(5) and Y30H Cyt b(5), as monitored by both UV-Vis and CD spectroscopy, as well as heme transfer studies from these proteins to apo-myoglobin, with wild-type Cyt b(5) under the same conditions for comparison. The reduced stability of both mutants indicates that both the H-bonding and hydrophobic interactions associated with Tyr30 contribute to the protein stability. Moreover, we performed molecular modeling studies, which revealed that the hydrophobic interaction in the local region of Y30F Cyt b(5) was well remained, whereas Y30H Cyt b(5) formed an H-bond network. These observations suggest that the conserved Tyr30 in Cyt b(5) is not replaceable due to the presence of both the H-bond network and hydrophobic interaction in the secondary sphere of the heme active site, As demonstrated here for Cyt b(5), it may be of practical importance for design of artificial heme proteins by engineering a Tyr in the secondary sphere with improved properties and functions. (C) 2016 Published by Elsevier B.V.
语种：
英文
展开
Synthesis and antitumor activity of novel N-(5-benzyl-4-(tert-butyl)thiazol-2-yl)-2-(piperazin-1-yl)acetamides
作者：
Wu, Zhilin;Ding, Na;Tang, Yuting;Ye, Jiao;Peng, Junmei;...
期刊：
Research on Chemical Intermediates ,2017年43(8):4833-4850 ISSN：0922-6168
通讯作者：
Hu, Aixi
作者机构：
[Ye, Jiao; Ding, Na; Peng, Junmei; Wu, Zhilin; Tang, Yuting; Hu, Aixi] Hunan Univ, Coll Chem & Chem Engn, Changsha, Hunan, Peoples R China.;[Wu, Zhilin] Univ South China, Sch Chem & Chem Engn, Hengyang, Hunan, Peoples R China.;[Peng, Junmei] Univ South China, Inst Pharm & Pharmacol, Hengyang, Hunan, Peoples R China.
通讯机构：
[Hu, Aixi] H;Hunan Univ, Coll Chem & Chem Engn, Changsha, Hunan, Peoples R China.
关键词：
Thiazole;Piperazinylacetamide;Antitumor activity;Cell cycle;Double staining
摘要：
A series of novel N-(5-benzyl-4-(tert-butyl) thiazol-2-yl)-2-(piperazin-1yl) acetamides were designed, synthesized and evaluated for their antitumor activities in vitro. The structures of the synthesized compounds were characterized by H-1 NMR, C-13 NMR and elemental analysis. In general, compounds 5a, 5c and 6a showed potent antiproliferative activity against HeLa (human cervical cancer) and A549 (human lung cancer) cell lines. Compound 6a, with the best inhibitory activity against HeLa cells (IC50 = 1.6 +/- 0.8 mu M), was selected to investigate the induced changes of cell morphology in the HeLa cell line by means of acridine orange (AO)/ethidium bromide (EB) double staining and cell cycle analysis using flow cytometry. The results indicated that compound 6a could induce cell apoptosis and cause G1-phase arrest in the cell division cycle.
语种：
英文
展开
A modified gelcasting approach to fabricate microscale randomized 1–3 piezoelectric arrays
作者：
Xie, Rui* ;Wang, Xiaofeng;Peng, Guowen;Xie, Tian;Zhang, Dou;...
期刊：
Ceramics International ,2017年43(1):144-148 ISSN：0272-8842
通讯作者：
Xie, Rui
作者机构：
[Wang, Hongqing; Xie, Rui; Peng, Guowen; Wang, Xiaofeng; Wang, Guoping] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Xie, Tian] Univ South China, Sch Econ & Management, Hengyang 421001, Peoples R China.;[Zhang, Dou; Zhou, Kechao] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.;[Huang, Guoji] Aerosp Res Inst Mat & Proc Technol, Dept Mat Ind & Dev, Beijing 100076, Peoples R China.
通讯机构：
[Xie, Rui] U;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.
关键词：
Gelcasting;Lead zirconate titanate;Rheology;Piezoelectric arrays;Weibull analysis
摘要：
A modified gelcasting approach was used to fabricate the microscale randomized 1–3 piezoelectric array, which involves the in situ polymerization of hydantion epoxy resin and 3,3′-Diaminodipropylamine (DPTA) in the lead zirconate titanate (PZT) suspensions with low viscosity and high solid loading. Rheological results demonstrated that the hydantion epoxy resin concentration had little effect on the viscosity of the premix solution, and therefore the optimized solid loading of the suspensions with 15.0 wt% resin could reach as high as 55.0 vol%. Weibull analysis also revealed that a more homogenous microstructure was obtained derived from the 55.0 vol% PZT suspension, where the Weibull modulus and the characteristic flexural strength reached the maximum value of 12.57 and 80.94 MPa. The excellent randomized piezoelectric pillar array with superior structural integrity and high fidelity was successfully fabricated. ©2016 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
展开
Structural control of the hybrid colloids by cooperative assembly of PS-b-PAA and semiconductor nanoparticles from the solvent aspects
作者：
Nie, Xiaobo* ;Xu, Yajun;Zhang, Ying
期刊：
Colloid and Polymer Science ,2017年295(5):817-826 ISSN：0303-402X
通讯作者：
Nie, Xiaobo
作者机构：
[Nie, Xiaobo; Zhang, Ying; Xu, Yajun] Univ South China, Coll Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Nie, Xiaobo] U;Univ South China, Coll Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
Block copolymer;Semiconductor nanoparticle;Micelles;Colloids;Fluorescence
摘要：
Well-defined polymer/inorganic nanoparticle (NP) hybrids are of vital importance to the development of nanomaterials with desired optical, electric, magnetic, and many other properties. We demonstrate the efficient incorporation of n-trioctylphosphine oxide (TOPO)-coated CdSe quantum dots (QDs) into polystyrene-b-polyacrylic acid (PS-b-PAA) colloids by a “solution phase self-assembly”approach. Driven by the hydrophobic interactions, the CdSe QDs are homogeneously encapsulated in the hybrid colloids. The sizes of the hybrid colloids with different structures, i.e., simple spherical micelles and big compound micelles, are tuned from 45 to 126 nm by varying the THF content in the cosolvents of THF and DMF, as well as changing the content or addition rate of selective solvent (water). The PS-b-PAA@CdSe QD hybrid colloids, which show brightly green fluorescence, can be endocytosed into biological cells and be released from the cells evolutionally, indicating their potential applications in biological imaging, labeling, and sensing, among others. ©2017, Springer-Verlag Berlin Heidelberg.
语种：
英文
展开
Efficient coagulation of graphene oxide on chitosan–metal oxide composites from aqueous solutions
作者：
Wang, Jian;Yao, Wen;Gu, Pengcheng;Yu, Shujun;Wang, Xiangxue;...
期刊：
Cellulose ,2017年24(2):851-861 ISSN：0969-0239
通讯作者：
Wang, Xiangke
作者机构：
[Wang, Xiangke; Wang, Jian; Wang, Xiangxue; Chen, Zhongshan; Gu, Pengcheng; Du, Yi; Yao, Wen; Yu, Shujun] North China Elect Power Univ, Sch Environm & Chem Engn, Beijing 102206, Peoples R China.;[Wang, Xiangke; Hayat, Tasawar] King Abdulaziz Univ, Fac Sci, NAAM Res Grp, Jeddah 21589, Saudi Arabia.;[Wang, Xiangke; Wang, Hongqing] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Wang, Xiangke] N;North China Elect Power Univ, Sch Environm & Chem Engn, Beijing 102206, Peoples R China.
关键词：
Chitosan–metal oxides;Coagulation;Graphene oxide;Mechanism
摘要：
In this study, chitosan–metal oxide composites (CS–MO) were prepared for graphene oxide (GO) removal from aqueous solutions. The results showed that the GO coagulation on CS–MO was dependent on pH and ionic strength. The maximum GO removal capacities reached 442.5mg/g on CS–Al2O3, 425.0mg/g on CS–ZnO and 421.2mg/g on CS–MgO, respectively, showing a huge advantage in the efficient elimination of GO from natural water system. The coagulation of GO on CS–MO was dominated by electrostatic attraction in acidic conditions and by hydrogen bonds in neutral and alkaline conditions. The findings are helpful to improve the current understanding of the environmental behavior of GO in natural aqueous systems. © 2016, Springer Science+Business Media Dordrecht.
语种：
英文
展开
不同形貌镁铝水滑石的可控合成及其对氯离子的吸附性能
作者：
柯国军;张琳;阳鹏飞;赵海东;谭弘俊
期刊：
精细化工 ,2017年34(10):1107-1113 ISSN：1003-5214
通讯作者：
Zhang, Lin(552410089@qq.com)
作者机构：
[柯国军; 张琳; 赵海东; 谭弘俊] School of Civil Engineering, University of South China, Hengyang, Hunan, 421001, China;[阳鹏飞] School of Chemistry and Chemical Engineering, University of South China, Hengyang, Hunan, 421001, China
关键词：
镁铝水滑石;形貌;吸附;氯离子;功能材料
摘要：
以硝酸镁、硝酸铝为原料,尿素为沉淀剂,采用水热法在不同条件下合成了不同形貌的镁铝水滑石LDH-1、 LDH-2、LDH-3。通过SEM、XRD、BET和EDS对合成的样品进行了表征;考察了不同形貌水滑石及其焙烧产物(LDO-1、LDO-2、LDO-3)对溶液中氯离子的吸附性能。结果表明:采用水热法添加乙二醇可合成棒状镁铝水滑石(LDH-1),添加乙醇可合成片状六边形镁铝水滑石(LDH-2),添加四丙基氢氧化铵可合成立方体镁铝水滑石(LDH-3)。其中,LDH-2形貌规整均一,片间形成交叉支撑结构,比表面积为115.311 m~2/g,在室温条件下,其对氯离子的最大吸附量为24.72 mg/g。LDO-2吸附氯离子的最优操作条件:温度为35 ℃,pH值为8,焙烧温度为450 ℃。在此条件下,焙烧产物(LDO-2)吸附氯离子的能力大大增强,最大吸附量为96.07 mg/g。
语种：
中文
展开
A highly sensitive and selective sensor based on a graphene-coated carbon paste electrode modified with a computationally designed boron-embedded duplex molecularly imprinted hybrid membrane for the sensing of lamotrigine
作者：
Wang, Hongjuan;Qian, Duo;Xiao, Xilin* ;Gao, Shuqin;Cheng, Jianlin;...
期刊：
Biosensors and Bioelectronics ,2017年94:663-670 ISSN：0956-5663
通讯作者：
Xiao, Xilin;Deng, Jian
作者机构：
[Xiao, XL; Deng, Jian; Wang, Hongjuan; Xiao, Xilin; Qian, Duo; Liao, Lifu; He, Bo] Univ South China, Coll Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.;[Gao, Shuqin] Univ South China, Coll Med, Hengyang 421001, Hunan, Peoples R China.;[Cheng, Jianlin] Univ South China, Coll Publ Hlth, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Xiao, XL; Deng, J] U;Univ South China, Coll Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
Computational design;Duplex molecularly imprinted hybrid membrane;Electrochemical sensor;Lamotrigine
摘要：
An innovative electrochemical sensor, based on a carbon paste electrode (CPE) modified with graphene (GR) and a boron-embedded duplex molecularly imprinted hybrid membrane (B-DMIHM), was fabricated for the highly sensitive and selective determination of lamotrigine (LMT). Density functional theory (DFT) was employed to study the interactions between the template and monomers to screen appropriate functional monomers for rational design of the B-DMIHM. The distinct synergic effect of GR and B-DMIHM was evidenced by the positive shift of the reduction peak potential of LMT at B-DMIHM/GR modified CPE (B-DMIHM/GR/CPE) by about 300 mV, and the 13-fold amplification of the peak current, compared to a bare carbon paste electrode (CPE). The electrochemical reduction mechanism of lamotrigine was investigated by different voltammetric techniques. It was illustrated that square wave voltammetry (SWV) was more sensitive than different pulse voltammetry (DPV) for the quantitative analysis of LMT. Thereafter, a highly sensitive electroanalytical method for LMT was established by SWV at B-DMIHM/GR/CPE with a good linear relationship from 5.0×10<sup>−8</sup>to 5.0×10<sup>−5</sup>and 5.0×10<sup>−5</sup>to 3.0×10<sup>−4</sup> mol L<sup>−1</sup>with a lower detection limit (1.52×10<sup>−9</sup> mol L<sup>−1</sup>) based on the lower linear range(S/N=3). The practical application of the sensor was demonstrated by determining the concentration of LMT in pharmaceutical and biological samples with good precision (RSD 1.04–4.41%) and acceptable recoveries (92.40–107.0%). ©2017 Elsevier B.V.
语种：
英文
展开
Controllable Synthesis of Ca-Mg-Al Layered Double Hydroxides and Calcined Layered Double Oxides for the Efficient Removal of U(VI) from Wastewater Solutions
作者：
Zou, Yidong;Wang, Xiangxue;Wu, Fen;Yu, Shujun;Hu, Yezi;...
期刊：
ACS SUSTAINABLE CHEMISTRY & ENGINEERING ,2017年5(1):1173-1185 ISSN：2168-0485
通讯作者：
Liu, Yunhai;Wang, Xiangke
作者机构：
[Liu, Yunhai; Zou, Yidong] East China Inst Technol, Sch Chem Biol & Mat Sci, Nanchang 330013, Jiangxi, Peoples R China.;[Wang, Xiangke; Song, Wencheng; Wang, Xiangxue; Hu, Yezi; Zou, Yidong; Yu, Shujun] North China Elect Power Univ, Sch Environm & Chem Engn, Beijing 102206, Peoples R China.;[Wu, Fen] Shanghai Univ Engn Sci, Sch Mat Engn, Po Shanghai 201620, Peoples R China.;[Wang, Xiangke; Wang, Hongqing] Univ South China, Sch Chem & Chem Engn, 28 Changsheng West Rd, Henyang 421001, Hunan, Peoples R China.;[Wang, Xiangke; Hayat, Tasawar] King Abdulaziz Univ, NAAM Res Grp, Fac Sci, Jeddah 21589, Saudi Arabia.
通讯机构：
[Liu, Yunhai] E;[Wang, Xiangke] N;[Wang, Xiangke] U;[Wang, Xiangke] K;East China Inst Technol, Sch Chem Biol & Mat Sci, Nanchang 330013, Jiangxi, Peoples R China.
关键词：
Controllable synthesis;Layered double hydroxides;Nanomaterials;U(VI)
摘要：
Novel rod-like ternary nanoscale layered double hydroxides (Ca-Mg-Al-LDH) and their bimetal derivatives (Ca-Mg-Al-LDOx, x: 200, 300, 400, 500, and 600 °C) were fabricated with a simple-green hydrothermal and calicination process. The interaction mechanism and adsorption property of U(VI) on Ca-Mg-Al-LDH and Ca-Mg-Al-LDOx were investigated by a batch technique and spectroscopy analysis, and the results indicated that U(VI) could form strong and stable surface complexes on Ca-Mg-Al-LDH and Ca-Mg-Al-LDOx surfaces. The adsorption capacity of U(VI) on various adsorbents could be controlled and adjusted through changing the calcination temperature, which was attributed to the different contents of various metal-oxide bonds (e.g., Ca-O, Mg-O, and Al-O). The adsorption capacities of U(VI) on these adsorbents were in the order of Ca-Mg-Al-LDO<inf>500</inf>(486.8 mg/g) >Ca-Mg-Al-LDO<inf>600</inf>(373.4 mg/g) >Ca-Mg-Al-LDO<inf>400</inf>(292.5 mg/g) >Ca-Mg-Al-LDO<inf>300</inf>(260.0 mg/g) >Ca-Mg-Al-LDO<inf>200</inf>(223.5 mg/g) >Ca-Mg-Al-LDH (132.5 mg/g), which might be attributed to more active surface sites and abundant "Ca-O and Al-O" with the increase of calcination temperature. The results of kinetic and thermodynamic studies demonstrated that the adsorption was a spontaneous and endothermic chemical process, and the better fitted Sips model revealed that the adsorption reaction was multilayer adsorption at low concentration of U(VI) and monolayer adsorption at high concentration of U(VI). This study provided highlights on the interaction mechanism of U(VI) with various metal-oxide bonds, and it could play an important role for the controllable adsorption capacity and effcient application in environmental remediation. ©2016 American Chemical Society.
语种：
英文
展开
Architecture of CoNx single clusters on nanocarbon as excellent oxygen reduction catalysts with high-efficient atomic utilization
作者：
He, Ting;Xue, Hui;Wang, Xiaojuan;He, Shuanghua;Lei, Yulai;...
期刊：
Nanoscale ,2017年9(24):8341-8348 ISSN：2040-3364
通讯作者：
Zhang, Yi;Xiang, Juan
作者机构：
[Xue, Hui; He, Ting; Lei, Yulai; Zhang, Y; Xiang, Juan; Zhang, Yi; Wang, Xiaojuan; Zhang, Yuyuan] Cent S Univ, Hunan Prov Key Lab Efficient & Clean Utilizat Man, Coll Chem & Chem Engn, 932 Lushan South Rd, Changsha, Hunan, Peoples R China.;[Wang, Xiaojuan] Univ South China, Coll Chem & Chem Engn, Hengyang, Hunan, Peoples R China.;[He, Shuanghua] Hefei Univ Technol, Sch Mech Engn, Hefei 230009, Peoples R China.;[Shen, Rujuan] Cent S Univ, State Key Lab Power Met, 932 Lushan South Rd, Changsha, Hunan, Peoples R China.
通讯机构：
[Zhang, Y; Xiang, J] C;Cent S Univ, Hunan Prov Key Lab Efficient & Clean Utilizat Man, Coll Chem & Chem Engn, 932 Lushan South Rd, Changsha, Hunan, Peoples R China.
摘要：
A new strategy to fabricate CoN<inf>x</inf>single cluster supported nanocarbon catalysts (C/P/2Co600) with enhanced atomic utilization towards the oxygen reduction reaction (ORR) is reported. N-Coordination protection and low-temperature pyrolysis are the two key factors for the formation of CoN<inf>x</inf>single clusters on nanocarbon supports. Morphological and structural identification confirmed the simultaneous anchoring of homo-dispersed CoN<inf>x</inf>single clusters and N-doping on the nanocarbon under relatively mild thermal treatment conditions. Expectedly, the obtained single cluster catalyst with a trace amount of metal atoms exhibited excellent ORR performance including a positive half-wave potential (0.846 V), a high mass activity (0.98 A mg<inf>Co</inf><sup>-1</sup>, ampere per milligram of cobalt) and outstanding chemical durability after 8000 potential cycles. We believe that our findings provide a new route for the rational design of low-cost and highly active ORR catalytic materials. ©2017 The Royal Society of Chemistry.
语种：
英文
展开
Enhanced performance of proton exchange membrane fuel cell by introducing nitrogen-doped CNTs in both catalyst layer and gas diffusion layer
作者：
Hou, Sanying;Chi, Bin;Liu, Guangzhi;Ren, Jianwei;Song, Huiyu* ;...
期刊：
Electrochimica Acta ,2017年253:142-150 ISSN：0013-4686
通讯作者：
Song, Huiyu;Liao, Shijun
作者机构：
[Chi, Bin; Song, Huiyu; Liao, Shijun; Hou, Sanying; Liu, Guangzhi] South China Univ Technol, Sch Chem & Chem Engn, Key Lab Fuel Cell Technol Guangdong Prov, Guangzhou, Guangdong, Peoples R China.;[Chi, Bin; Song, Huiyu; Liao, Shijun; Hou, Sanying; Liu, Guangzhi] South China Univ Technol, Sch Chem & Chem Engn, Key Lab New Energy Technol Guangdong Univ, Guangzhou, Guangdong, Peoples R China.;[Hou, Sanying] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Ren, Jianwei] CSIR, HySA Infrastruct Ctr Competence Mat Sci & Mfg, POB 395, ZA-0001 Pretoria, South Africa.
通讯机构：
[Song, HY; Liao, SJ] S;South China Univ Technol, Sch Chem & Chem Engn, Key Lab Fuel Cell Technol Guangdong Prov, Guangzhou, Guangdong, Peoples R China.;South China Univ Technol, Sch Chem & Chem Engn, Key Lab New Energy Technol Guangdong Univ, Guangzhou, Guangdong, Peoples R China.
关键词：
Proton exchange membrane fuel cell;Catalyst layer;Microporous layer;Nitrogen-doped;Carbon nanotubes
摘要：
The performance of the proton exchange membrane fuel cell (PEMFC) is significantly improved through introducing nitrogen-doped carbon nanotubes (NCNTs) into the catalyst layer (CL) and microporous layer (MPL) of the membrane electrode assembly (MEA), it reveals by SEM images that the NCNTs are uniformly dispersed in CL and MPL, resulting in the more plenty of porosity, higher surface area, better conductivity, and better prevention of the layer cracks. The BET surface area and pore volume of MPL are increased by 88% and 77% respectively with the addition of 20 wt% of NCNTs in MPL. The membrane electrode assembly (MEA) with adding 20 wt% NCNTs both in cathode CL and in cathode GDL can yield the best cell performance. At a cell temperature of 70 °C and 30 psi back pressures, the current density is up to 1000 mA cm−2 at 0.7 V and 1600 mA cm−2 at 0.6 V, and the max power density reaches 997 mW cm−2. © 2017 Elsevier Ltd
语种：
英文
展开
反应结构材料制备技术的研究现状
作者：
陶玉强;白书欣;阳世清;李顺
期刊：
中国有色金属学报 ,2017年27(10):2079-2090 ISSN：1004-0609
通讯作者：
Tao, Yu-Qiang(87145182@qq.com)
作者机构：
[陶玉强] School of Chemistry and Chemical Engineering, University of South China, Hengyang, 421001, China;[陶玉强; 白书欣; 阳世清; 李顺] College of Aerospace Science and Engineering, National University of Defense Technology, Changsha, 410073, China
通讯机构：
School of Chemistry and Chemical Engineering, University of South China, Hengyang, China
关键词：
反应结构材料;热反应;制备技术;铝热剂;金属间化合物型复合材料
摘要：
简单介绍反应结构材料(Reactive material structures,RMS)的概念、种类、应用、能量特性、力学性能要求以及应用时存在的主要困难,概述近些年来国内外研究者对RMS开展的研究工作,重点介绍了RMS的常用制备技术及其结构设计方面的研究状况。通过分析材料制备技术的特点、致密化原理和强化机制,并结合RMS的反应特性,对比分析了各种RMS制备技术的优缺点,指出它们的适用范围和应用前景,为RMS制备技术选择提供参考。指出组元多元化、新材料体系开发、强化机制研究、低温致密化和可控塑性变形强化技术开发、大型复杂样件制备技术开发、组织结构和复合方式优化是RMS及其制备技术的主要发展趋势。
语种：
中文
展开
磁性功能改性杯[4]芳烃胺肟衍生物及其对铀的吸附特性
作者：
彭国文;余丽梅;肖方竹;蒲移秋;谢睿;...
期刊：
原子能科学技术 ,2017年51(5):783-789 ISSN：1000-6931
作者机构：
[谢睿; 余丽梅; 蒲移秋; 彭国文] School of Chemistry and Chemical Engineering, University of South China, Hengyang, 421001, China;[肖方竹; 彭国文; 刘永] Hunan Province Engineering Technology Research Center of Uranium Tailings Treatment, University of South China, Hengyang, 421001, China;[肖方竹; 彭国文] Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, China
关键词：
杯[4]芳烃胺肟衍生物;磁性功能化;铀;吸附特性;再生
摘要：
以氨基化改性磁性纳米Fe_3O_4粒子为载体,将杯[4]芳烃胺肟衍生物进行磁性功能化改性,制备得到立体构象稳定、与UO~(2+)2空间配位构型匹配的杯[4]芳烃胺肟衍生物磁性功能材料(MFM-AOCA)。并采用红外光谱、扫描电镜进行了结构表征。考察了溶液pH值、铀初始浓度、MFM-AOCA用量和吸附时间等因素对吸附的影响。结果表明:杯[4]芳烃胺肟衍生物磁性功能修饰后,具有较大的比表面积,其吸附铀的最佳条件是pH值为3.5、铀初始浓度为40 mg/L、吸附剂用量为40 mg和吸附时间为3.5 h。吸附动力学模型和吸附等温模型研究表明,MFM-AOCA对铀的吸附动力学过程符合准二级动力学模型,所得到的相关系数大于0.99;吸附等温线符合Langmuir等温线模型,其最大理论吸附量为141.28 mg/g。使用3种不同的解吸剂对MFM-AOCA解吸再生6次后,其对铀的吸附率均在80%以上,说明该MFM-AOCA具有良好的再生性能。
语种：
中文
展开
Rational design and synthesis of monodispersed hierarchical SiO2 @layered double hydroxide nanocomposites for efficient removal of pollutants from aqueous solution
作者：
Yang, Dongxu;Song, Shuang;Zou, Yidong;Wang, Xiangxue;Yu, Shujun;...
期刊：
Chemical Engineering Journal ,2017年323:143-152 ISSN：1385-8947
通讯作者：
Wang, Hongqing;Wang, Xiangke
作者机构：
[Wang, Xiangke; Wang, Hongqing; Yang, Dongxu] Univ South China, Sch Chem & Chem Engn, 28 Changsheng West Rd, Hengyang 421001, Hunan, Peoples R China.;[Wang, Xiangke; Wen, Tao; Yang, Dongxu; Wang, Xiangxue; Song, Shuang; Wang, HQ; Wang, XK; Zou, Yidong; Yu, Shujun] North China Elect Power Univ, Sch Environm & Chem Engn, Beijing 102206, Peoples R China.;[Wang, Xiangke; Hayat, Tasawar; Alsaedi, Ahmed] King Abdulaziz Univ, Fac Sci, NAAM Res Grp, Jeddah 21589, Saudi Arabia.;[Wang, Xiangke; Wang, Hongqing; Wen, Tao; Yang, Dongxu; Wang, Xiangxue; Song, Shuang; Zou, Yidong; Hayat, Tasawar; Alsaedi, Ahmed; Yu, Shujun] Soochow Univ, Sch Radiol & Interdisciplinary Sci, Jiangsu Higher Educ Inst, Collaborat Innovat Ctr Radiat Med, Suzhou 215123, Peoples R China.
通讯机构：
[Wang, HQ; Wang, XK] N;North China Elect Power Univ, Sch Environm & Chem Engn, Beijing 102206, Peoples R China.
关键词：
Layered double hydroxides;Methyl orange;SiO2@LDH;Sorption;U(VI)
摘要：
Hierarchical silicon dioxide-@-layered double hydroxide (SiO2@LDH) nanocomposites were synthesized by a facile in situ co-precipitation method, and characterized by XRD, FESEM, FT-IR and XPS in detail. The sorption of uranium (U(VI)) and methyl orange (MO) on SiO2@LDH were investigated as a function of pH, ionic strength, contact time and temperature. The results indicated that the sorption of U(VI) and MO were strongly dependent on pH, and weakly dependent on ionic strength, demonstrating that the interaction of U(VI) was mainly dominated by inner-sphere surface complexation and the sorption of MO was mainly attributed to electrostatic attraction due to the high removal efficiency (∼98% within 4h for U(VI) ions, and ∼92% within 10min for MO). The kinetics sorption of U(VI) and MO both followed the pseudo-second-order model well, suggesting that the sorption processes were chemical sorption. The sorption isotherms of U(VI) and MO on SiO2@LDH were well fitted by the Langmuir model, and the maximum sorption capacities of SiO2@LDH were calculated to be 303.1mg·g−1 for U(VI) and 166.1mg·g−1 for MO. The thermodynamic parameters revealed that the sorption of U(VI) and MO was spontaneous process. Integrating the experimental result analysis, the hierarchical SiO2@LDH may be a promising material for the efficient elimination of radionuclides and dyes from aqueous solutions in natural environmental pollution cleanup. © 2017
语种：
英文
展开
Enantioselective determination of S-ornidazole by using carbon paste electrode modified with boron-embedded conductive copolymer-polysiloxane-based molecularly imprinted hybrid film
作者：
Wang, Hongjuan;Qian, Duo;Xiao, Xilin* ;He, Bo;Gao, Shuqin;...
期刊：
Electrochimica Acta ,2017年246:338-347 ISSN：0013-4686
通讯作者：
Xiao, Xilin;Deng, Jian
作者机构：
[Xiao, XL; Deng, Jian; Wang, Hongjuan; Xiao, Xilin; Qian, Duo; Liao, Lifu; He, Bo] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.;[Gao, Shuqin] Univ South China, Sch Med, Hengyang 421001, Hunan, Peoples R China.;[Shi, Han] Bur Anim Husb & Fisheries, Shaodong 422800, Hunan, Peoples R China.
通讯机构：
[Xiao, XL; Deng, J] U;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
S-ornidazole;Enantioselective determination;Molecularly imprinted hybrid film;Electrochemical sensor
摘要：
Highly selective determination of enantiomers by electrochemical sensors with simple recognition elements is of great interest in pharmaceutics, biochemistry and medical fields. The present work developed an innovative electrochemical sensor, which based on boron-embedded molecularly imprinted hybrid film (B-MIHF) modified carbon paste electrode (CPE), for enantioselective determination of S-ornidazole (S-ONZ). A boron-embedded conductive copolymer was firstly electro polymerized on carbon paste electrode (CPE), and then molecularly imprinted polysiloxanes (MIP) were hydrolyzed and condensed over the conductive copolymer layer via a sol-gel process. The as-prepared B-MIHF, comprised the advantages of boron-embedded conductive copolymer and molecularly imprinted polysiloxanes, could not only implement direct signal transformation between imprinted cavities and sensing elements, but show amazing selectivity to template S-ornidazole. Above all, the introduction of coordinate interaction formed between trisubstituted boron atoms embedded in B-MIHF matrix and nitrogen atoms of template endow the sensor with intensive enantioselectivity. Under optimum experiments conditions, the reduction peak currents of S-ONZ by differential pulse voltammetry were linear to S-ONZ concentrations in the range from 6.0 x 10(8) to 1.0 x 10(6) mol L-1 and 1.0 x 10(-6) to 3.5 x 10(4) mol L-1 with a detection limit of 1.1 x 10(-8) mol L-1. The B-MIHF-based sensor has been successfully applied for the determination of S-ONZ in pharmaceutical and biological samples with good precision (RSD 2.25-4.11%) and acceptable recoveries (96.00-108.00%). (C) 2017 Elsevier Ltd. All rights reserved.
语种：
英文
展开
Heme-containing enzymes and inhibitors for tryptophan metabolism
作者：
Yan, Daojing;Lin, Ying-Wu;Tan, Xiangshi*
期刊：
METALLOMICS ,2017年9(9):1230-1240 ISSN：1756-5901
通讯作者：
Tan, Xiangshi
作者机构：
[Tan, Xiangshi; Yan, Daojing] Fudan Univ, Dept Chem, Shanghai 200433, Peoples R China.;[Tan, Xiangshi; Yan, Daojing] Fudan Univ, Inst Biomed Sci, Shanghai 200433, Peoples R China.;[Lin, Ying-Wu] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Tan, Xiangshi] F;Fudan Univ, Dept Chem, Shanghai 200433, Peoples R China.;Fudan Univ, Inst Biomed Sci, Shanghai 200433, Peoples R China.
摘要：
Iron-containing enzymes such as heme enzymes play crucial roles in biological systems. Three distinct heme-containing dioxygenase enzymes, tryptophan 2,3-dioxygenase (TDO), indoleamine 2,3-dioxygenase 1 (IDO1) and indoleamine 2,3-dioxygenase 2 (IDO2) catalyze the initial and rate-limiting step of L-tryptophan catabolism through the kynurenine pathway in mammals. Overexpression of these enzymes causes depletion of tryptophan and the accumulation of metabolic products, which contributes to tumor immune tolerance and immune dysregulation in a variety of disease pathologies. In the past few decades, IDO1 has garnered the most attention as a therapeutic target with great potential in cancer immunotherapy. Many potential inhibitors of IDO1 have been designed, synthesized and evaluated, among which indoximod (D-1-MT), INCB024360, GDC-0919 (formerly NLG-919), and an IDO1 peptide-based vaccine have advanced to the clinical trial stage. However, recently, the roles of TDO and IDO2 have been elucidated in immune suppression. In this review, the current drug discovery landscape for targeting TDO, IDO1 and IDO2 is highlighted, with particular attention to the recent use of drugs in clinical trials. Moreover, the crystal structures of these enzymes, in complex with inhibitors, and the mechanisms of Trp catabolism in the first step, are summarized to provide information for facilitating the discovery of new enzyme inhibitors.
语种：
英文
展开
Enhancement of Electrochemical Performance by the Oxygen Vacancies in Hematite as Anode Material for Lithium-Ion Batteries
作者：
Zeng, Peiyuan;Zhao, Yueying;Lin, Yingwu;Wang, Xiaoxiao;Li, Jianwen;...
期刊：
Nanoscale Research Letters ,2017年12(1):1-9 ISSN：1931-7573
通讯作者：
Fang, Zhen
作者机构：
[Li, Jianwen; Fang, Zhen; Zeng, Peiyuan; Wang, Xiaoxiao; Wang, Wanwan; Zhao, Yueying] Anhui Normal Univ, Coll Chem & Mat Sci, Key Lab Funct Mol Solids, Minist Educ,Ctr Nano Sci & Technol, Wuhu 241000, Peoples R China.;[Lin, Yingwu] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Fang, Zhen] East Beijing Rd 1, Wuhu, Anhui, Peoples R China.
通讯机构：
[Fang, Zhen] A;[Fang, Zhen] E;Anhui Normal Univ, Coll Chem & Mat Sci, Key Lab Funct Mol Solids, Minist Educ,Ctr Nano Sci & Technol, Wuhu 241000, Peoples R China.;East Beijing Rd 1, Wuhu, Anhui, Peoples R China.
关键词：
Hematite;Oxygen vacancies;Calcination;Lithium-ion batteries
摘要：
The application of hematite in lithium-ion batteries (LIBs) has been severely limited because of its poor cycling stability and rate performance. To solve this problem, hematite nanoparticles with oxygen vacancies have been rationally designed by a facile sol–gel method and a sequential carbon-thermic reduction process. Thanks to the existence of oxygen vacancies, the electrochemical performance of the as-obtained hematite nanoparticles is greatly enhancing. When used as the anode material in LIBs, it can deliver a reversible capacity of 1252 mAh g<sup>−1</sup>at 2 C after 400 cycles. Meanwhile, the as-obtained hematite nanoparticles also exhibit excellent rate performance as compared to its counterparts. This method not only provides a new approach for the development of hematite with enhanced electrochemical performance but also sheds new light on the synthesis of other kinds of metal oxides with oxygen vacancies. ©2017, The Author(s).
语种：
英文
展开
Orthogonal strategy development using reversed macroporous resin coupled with hydrophilic interaction liquid chromatography for the separation of ginsenosides from ginseng root extract
作者：
Wu, Yajun;Liu, Jingjing;Gu, Su;Lin, Li;Chen, Yingzhuang* ;...
期刊：
JOURNAL OF SEPARATION SCIENCE ,2017年40(21):4128-4134 ISSN：1615-9306
通讯作者：
Chen, Yingzhuang
作者机构：
[Liu, Jingjing; Wu, Yajun; Chen, Yingzhuang; Gu, Su; Lin, Li; Chen, Bo; Ma, Ming] Hunan Normal Univ, Minist Educ, Key Lab Phytochem R&D Hunan Prov, Changsha 410081, Hunan, Peoples R China.;[Liu, Jingjing; Wu, Yajun; Chen, Yingzhuang; Gu, Su; Lin, Li; Chen, Bo; Ma, Ming] Hunan Normal Univ, Minist Educ, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.;[Liu, Jingjing] Univ South China, Coll Chem & Chem Engn, Hengyang, Peoples R China.
通讯机构：
[Chen, Yingzhuang] H;Hunan Normal Univ, Minist Educ, Key Lab Phytochem R&D Hunan Prov, Changsha 410081, Hunan, Peoples R China.;Hunan Normal Univ, Minist Educ, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.
关键词：
ginsenosides;hydrophilic interaction liquid chromatography;macroporous resins;reversed-phase liquid chromatography
摘要：
Ginsenosides have been widely conceded as having various biological activities and are considered to be the active ingredient of ginseng. Nowadays, preparative high-performance liquid chromatography is considered to be a highly efficient method for ginseng saponins purification and preparation. However, in the process of practical application, due to the complex and varied composition of natural products and relatively simple pretreatment process, it is likely to block the chromatographic column and affect the separation efficiency and its service life. In this work, an orthogonal strategy was developed;in the first-dimension separation, reverse-phase macroporous resin was applied to remove impurities in ginseng crude extracts and classified ginseng extracts into protopanaxatriol and protopanaxadiol fractions. In the second-dimension separation, the obtained fractions were further separated by a preparative hydrophilic column, and finally yielded 11 pure compounds. Eight of them identified as ginsenoside Rh<inf>1</inf>, Rg<inf>2</inf>, Rd, Rc, Rb<inf>2</inf>, Rb<inf>1</inf>, Rg<inf>1</inf>, and Re by standards comparison and electrospray ionization mass spectrometry. The purity of these ginsenosides was assessed by high-performance liquid chromatography with UV detection. ©2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
语种：
英文
展开
Hydrothermal synthesis of ZnO flower-reduced graphene oxide composite for electrochemical determination of ascorbic acid
作者：
Long, Wei;Fu, Li*
期刊：
FULLERENES NANOTUBES AND CARBON NANOSTRUCTURES ,2017年25(7):404-409 ISSN：1536-383X
通讯作者：
Fu, Li
作者机构：
[Long, Wei; Fu, Li] Univ South China, Journal Res Inst, Hengyang 421001, Hunan, Peoples R China.;[Long, Wei] Univ South China, Sch Chem & Chem Engn, Hengyang, Hunan, Peoples R China.;[Fu, Li] Hangzhou Dianzi Univ, Coll Mat & Environm Engn, Hangzhou, Zhejiang, Peoples R China.
通讯机构：
[Fu, Li] U;Univ South China, Journal Res Inst, Hengyang 421001, Hunan, Peoples R China.
关键词：
Graphene;zinc oxide;electrochemical sensor;ascorbic acid;hydrothermal synthesis
摘要：
In this work, reduced graphene oxide coated zinc oxide flower (ZnO–RGO) nanocomposite has been prepared via a simple one-pot hydrothermal synthesis method. The morphology and properties of the proposed ZnO–RGO were characterized using SEM, Raman and UV–VIS spectroscopy. Then, an ascorbic acid (AA) electrochemical sensor was prepared based on a glassy carbon electrode (GCE) modified with the ZnO–RGO nanocomposite. An advanced performance was recorded on the ZnO–RGO/GCE compared with that of the bare GCE, ZnO/GCE, and RGO/GCE. The proposed electrochemical sensor exhibited a wide linear detection from 5 μM to 2 mM with a low detection limit of 1.2 μM. Further, the proposed AA electrochemical sensor showed a good repeatability, reproducibility and stability. ©2017 Taylor & Francis Group, LLC.
语种：
英文
展开
“Turn-On” fluorescent chemosensor based on β-diketone for detecting Th4+ ions in Aqueous Solution and application in living cell imaging
作者：
Zheng, Shulin;Wang, Hongqing* ;Hu, Qinghua;Wang, Yuyuan;Hu, Jiangke;...
期刊：
Sensors and Actuators B-Chemical ,2017年253:766-772 ISSN：0925-4005
通讯作者：
Wang, Hongqing
作者机构：
[Wang, Hongqing; Liu, Pengying; Hu, Jiangke; Zhou, Fenfen; Hu, Qinghua; Wang, Yuyuan; Zheng, Shulin] Univ South China, Sch Chem & Chem Engn, 28 Changsheng West Rd, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Wang, Hongqing] U;Univ South China, Sch Chem & Chem Engn, 28 Changsheng West Rd, Hengyang 421001, Hunan, Peoples R China.
关键词：
Fluorescent sensor;Thorium ions (Th4+);beta-diketone;Density functional theory (DFT) calculations;Cell imaging
摘要：
A fluorescent sensor Hn based on β-diketone derivative for Th<sup>4+</sup>ions was designed and investigated, which showed high selectivity in the present of other metal ions even UO<inf>2</inf><sup>2+</sup>in CH<inf>3</inf>OH:H<inf>2</inf>O (v/v = 2:8, pH = 7.2) solution. Meanwhile, the binding mode of the sensor Hn with Th<sup>4+</sup>ions was found to be 1:1 with association constant of 2.46 × 10<sup>4</sup> M<sup>−1</sup><inf>.</inf>And there was linear relationship between the fluorescent intensity of Hn-Th<sup>4+</sup>and the concentration of Th<sup>4+</sup>ions covering a range of 0.06 μM–1.0 μM and the detection limit was 0.0344 μM. At the same time, the interaction properties between the sensor Hn and Th<sup>4+</sup>ions and the fluorescent mechanism were investigated by IR,<sup>1</sup>HNMR and DFT. Most importantly, this fluorescent sensor was successfully utilized for the fluorescent imaging of Th<sup>4+</sup>ions in living cells. ©2017 Elsevier B.V.
语种：
英文
展开
