Study of the biological effectiveness of a nanosilver-epidermal growth factor sustained-release carrier
作者：
Zhou, Jian-Da;Wang, Shao-Hua;Liu, Rui;Zhou, Chun-Jiao;Cao, Ke;...
期刊：
EXPERIMENTAL AND THERAPEUTIC MEDICINE ,2013年5(4):1231-1235 ISSN：1792-0981
通讯作者：
Chen, Feng-Hua
作者机构：
[Liu, Rui; Zhou, Jian-Da; Cao, Ke; Chen, Yao; Wang, Shao-Hua; Liu, Jin-Yan] Cent S Univ, Xiang Ya Hosp 3, Changsha 410013, Hunan, Peoples R China.;[Zhou, Chun-Jiao] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Chen, Feng-Hua] Cent S Univ, Xiang Ya Hosp, Changsha 410008, Hunan, Peoples R China.;[Chen, Feng-Hua] Cent S Univ, Xiang Ya Hosp 3, Dept Neurosurg, 87 Xiangya Rd, Changsha 410008, Hunan, Peoples R China.
通讯机构：
[Chen, Feng-Hua] C;Cent S Univ, Xiang Ya Hosp 3, Dept Neurosurg, 87 Xiangya Rd, Changsha 410008, Hunan, Peoples R China.
关键词：
antibacterial;cell proliferation;epidermal growth factor;nanosilver;wound
摘要：
The aim of the present study was to elucidate the biological effectiveness and character of a nanosilver-epidermal growth factor (EGF) sustained-release carrier. This was synthesized using the self-assembly method and then characterized by transmission electron microscopy and UV spectrophotometry. The biological activity of the sustained release carrier was determined through cytological, bacteriological and wound-healing experiments. The results showed that the nanosilver-EGF sustained-release carrier was well dispersed with uniform particle size and that it had good antibacterial properties similar to those of nanosilver. The nanosilver-EGF sustained-release carrier is superior to EGFs in effectively promoting cell division and proliferation. The results of the wound-healing experiments provide evidence of its curative effects.
语种：
英文
展开
Effects of a Steam Explosion Pretreatment on Sugar Production by Enzymatic Hydrolysis and Structural Properties of Reed Straw
作者：
Hu, Qiulong;Su, Xiaojun;Tan, Lin;Liu, Xianghua;Wu, Anjun;...
期刊：
Bioscience, Biotechnology, and Biochemistry ,2013年77(11):2181-2187 ISSN：0916-8451
通讯作者：
Xiong, Xingyao
作者机构：
[Tian, Kaizhong; Su, Xiaojun; Liu, Xianghua; Xiong, Xingyao; Su, Dingding; Hu, Qiulong] Hunan Agr Univ, Hunan Prov Key Lab Crop Gennplasm Innovat & Utili, Changsha 410128, Hunan, Peoples R China.;[Xiong, Xingyao] Chinese Acad Agr Sci, Inst Vegetables & Flowers, Beijing 100081, Peoples R China.;[Tan, Lin] Hunan Agr Univ, Coll Plant Protect, Hunan Prov Key Lab Biol & Control Plant Dis & Ins, Changsha 410128, Hunan, Peoples R China.;[Wu, Anjun; Liu, Xianghua] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Xiong, Xingyao] H;Hunan Agr Univ, Hunan Prov Key Lab Crop Gennplasm Innovat & Utili, Changsha 410128, Hunan, Peoples R China.
关键词：
reed straw;steam explosion pretreatment;sugar production;enzymatic hydrolysis;structural properties
摘要：
Reed lignocellulose was subjected to a steam explosion pretreatment to obtain a high conversion rate of sugar after subsequent enzymatic hydrolysis using a commercial cellulase mixture. Under conditions of differing temperature (200 °C, 220 °C and 240 °C) and residence time (2, 5, and 8 min), the effect of the pretreatment on the sugar yield from enzymatic hydrolysis was studied. The highest respective reducing sugar and glucose yields were 36.14% and 15.35% after 60-h enzymatic hydrolysis of reed straw that had been pretreated with a steam explosion at 220 °C for 5 min. Fourier transform infrared spectrophotometry (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used in this study to comprehensively investigate the steam explosion-induced changes in the organizational structure and morphological properties of reed straw to analyze the reason for the increased sugar yield from enzymatic hydrolysis after the steam explosion.
语种：
英文
展开
In situ amplification signaling-based autonomous aptameric machine for the sensitive fluorescence detection ofcocaine
作者：
Xie, Su-Jin;Zhou, Hui;Liu, Dengyou;Shen, Guo-Li;Yu, Ruqin;...
期刊：
Biosensors and Bioelectronics ,2013年44(1):95-100 ISSN：0956-5663
通讯作者：
Wu, Zai-Sheng
作者机构：
[Shen, Guo-Li; Yu, Ruqin; Zhou, Hui; Xie, Su-Jin; Wu, Zai-Sheng] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Liu, Dengyou] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Wu, Zai-Sheng] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
关键词：
Aptamer;Autonomous DNA machine;Cocaine detection;Integrated signal transduction
摘要：
The development of autonomous DNA machines and their use for specific sensing purpose have recently attracted considerable research attention. In existing autonomous machines, the target recognition process and signal transduction are separated from each other. This results in misunderstanding of the operation behavior, and the assay capability is compromised when serving as a sensing tool. In this communication, the integrated signal transduction-based autonomous aptameric machine, in which the recognition element and signal reporters are integrated into a DNA strand, is developed. This new machine can execute the in situ amplification of target binding-induced signal. The authentic operation behavior of autonomous DNA machine is discovered: the machine's products directly hybridize to the "track" rather than to the signaling probes. Along this line, the machine is employed to detect the cocaine in a more straightforward fashion, and improved assay characteristics (for example, the dynamic response range is widened by more than 500-fold) are achieved. Our efforts not only clarify the concept described in traditional autonomous DNA machines but also have made technological advancements that are expected to be especially valuable in designing nucleic acid-based machines employed in basic research and medical diagnosis. © 2013 Elsevier B.V.
语种：
英文
展开
Strain-Sensitive Current-Voltage Characteristics of ZnSe Nanowire in Metal-Semiconductor-Metal Nanostructure
作者：
Tan, Yu;Wang Yan-Guo*
期刊：
中国物理快报：英文版 ,2013年30(11): 117901-1-117901-5 ISSN：0256-307X
通讯作者：
Wang Yan-Guo
作者机构：
[Wang Yan-Guo] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Chinese Acad Sci, Inst Phys, Beijing Natl Lab Condensed Matter Phys, Beijing 100190, Peoples R China.
通讯机构：
[Wang Yan-Guo] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Strain-Sensitive;Metal-Semiconductor-Metal;Nanostructure
摘要：
Experimental investigation of electrical transport properties is carried out by in situ transmission electron microscopy (TEM) to explore the effect of local strain in ZnSe nanowires (NWs) on improvement of electron transport of Au-ZnSe NW-Au (M-S-M) nanostructure. The results show that the threshold voltage due to the Schottky barrier at the metal-semiconductor NW (M-S) nanocontact is found to decrease significantly when the ZnSe NW bends at the Au-ZnSe junction by the movable probe which can apply longitudinal compression, leading to current-voltage (I - V) characteristics of the M-S-M nanostructure being transformed from a nearly symmetrical to an asymmetrical feature. Alternation of the I - V characteristic can be ascribed to significant depression of the Schottky barrier at the M-S nanocontact due to the band gap being narrowed by highly localized strain. As a result, the I - V characteristics of the M-S-M nanostructure are strain-sensitive and can be modified by local strain intentionally produced in the semiconductor NW. The modifiable I - V characteristics of M-S-M nanostructure confirm that the strain can be used for improvement of transport property of the semiconductor NW-based nanoelectronics with the M-S-M nanostructure. © 2013 Chinese Physical Society and IOP Publishing Ltd.
语种：
英文
展开
The effect of an incident electron beam on the I-V characteristics of a Au-ZnSe nanowire-Au nanostructure
作者：
Tan Yu;Wang Yan-Guo*
期刊：
中国物理快报：英文版 ,2013年30(4):47901-047901 ISSN：0256-307X
通讯作者：
Wang Yan-Guo
作者机构：
[Tan Yu] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Wang Yan-Guo] Chinese Acad Sci, Inst Phys, Beijing Lab Condensed Matter Phys, Beijing 100190, Peoples R China.;[Wang Yan-Guo] Chinese Acad Sci, Inst Phys, Beijing Lab Condensed Matter Phys, POB 603, Beijing 100190, Peoples R China.
通讯机构：
[Wang Yan-Guo] C;Chinese Acad Sci, Inst Phys, Beijing Lab Condensed Matter Phys, POB 603, Beijing 100190, Peoples R China.
摘要：
In order to the modify electron transport property of a metal-semiconductor nanowire(NW)-metal (M-S-M) nanostructure, the effect of high-energy electron irradiation on the current-voltage (I-V) characteristics of M-S-M nanostructure is investigated by in situ transmission electron microscopy. Experimentally measured I-V characteristics of an M-S-M nanostructure can be obviously modified under electron beam irradiation. The current increases rapidly due to increase of the carrier densities resulting from the electron-hole pair excitation in the NW irradiated by the electron beam. If the electron beam is focused on the NW (M-S) nanocontact, the electrons in the Au electrode are excited to higher energy states above the height of the Schottky barrier that becomes transparent to the conduction electrons. As a result, the nonlinear to linear I-V characteristics can be observed. The experimentally revealed I-V characteristics corresponding to transformation from the rectification to Ohm strongly suggest that the intrinsic transport property of the M-S nanocontact can be completely modified by irradiation of the high-energy electron beam. © 2013 Chinese Physical Society and IOP Publishing Ltd.
语种：
英文
展开
Folate-conjugated Fe_3O_4 nanoparticles for in vivo tumor labeling
作者：
Zhou, Chun-jiao;Wang, Shao-hua;Zhou, Yu;Rong, Peng-fei;Chen, Zi-zi;...
期刊：
中国有色金属学报(英文版) ,2013年23(7):2079-2084 ISSN：1003-6326
通讯作者：
Zhou, Jian-da
作者机构：
[Zhou, Chun-jiao; Zhou, Yu] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Zhou, Jian-da; Chen, Zi-zi; Wang, Shao-hua; Liu, Jin-yan; Rong, Peng-fei] Cent S Univ, Xiangya Hosp 3, Changsha 410013, Hunan, Peoples R China.
通讯机构：
[Zhou, Jian-da] C;Cent S Univ, Xiangya Hosp 3, Changsha 410013, Hunan, Peoples R China.
关键词：
Fe_3O_4 nanoparticles;superparamagnetic property;folic acid;tumor;conjugation;magnetic resonance imaging (MRI);cell labeling
摘要：
Highly biocompatible superparamagnetic Fe3O4 nanoparticles were synthesized by amide of folic acid (FA) ligands and the NH2-group onto the surface of Fe3O4 nanoparticles. The as-synthesized folate-conjugated Fe3O4 nanoparticles were characterized by X-ray diffraction diffractometer, transmission electron microscope, FT-IR spectrometer, vibrating sample magnetometer, and dynamic light scattering instrument. The in vivo labeling effect of folate-conjugated Fe3O4 nanoparticles on the hepatoma cells was investigated in tumor-bearing rat. The results demonstrate that the as-prepared nanoparticles have cubic structure of Fe3O4 with a particle size of about 8 nm and hydrated diameter of 25.7 nm at a saturation magnetization of 51 A.m(2)/kg. These nanoparticles possess good physiological stability, low cytotoxicity on human skin fibroblasts and negligible effect on Wistar rats at the concentration as high as 3 mg/kg body mass. The folate-conjugated Fe3O4 nanoparticles could be effectively mediated into the human hepatoma Bel 7402 cells through the binding of folate and folic acid receptor, enhancing the signal contrast of tumor tissue and surrounding normal tissue in MRI imaging. It is in favor of the tumor cells labeling, tracing, magnetic resonance imaging (MRI) target detection and magnetic hyperthermia.
语种：
英文
展开
Studies on correlation between fruit and leaf of citrus based on fractal dimension
作者：
Wen, Zhiyuan* ;Cao, Leping
期刊：
Research on Crops ,2013年14(3):870-875 ISSN：0972-3226
通讯作者：
Wen, Zhiyuan
作者机构：
[Cao, Leping; Wen, Zhiyuan] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Wen, Zhiyuan] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Citrus;correlation;mass;prediction;shape;size
摘要：
This paper investigates the statistical distribution of fruit size, shape, mass and leaf size, shape, and the correlation between fruits and leaves of Citrus unshiu Marc. cv. unbergii Nakai, Citrus sinensis Bonanza and Luxi seedless Citrus reticulata Blanco cv. Ponkan in the same plantation. After the selective image cropping, background removing and image binaryzation and boundary detection and thinning to the images of the selective samples from the three varieties, it comes to the data of the boundary pixel of fruits and leaves, and those of inner pixel of fruits and leaves, then treats them as the data of their perimeter and area, respectively, next with the perimeter-area method, it gets the fractal dimensions, which characterize the shape of fruit and leaf, and that the correlation coefficient between fruits and leaves is above 0.92 after the analysis of the fruit size, shape weight and leaf size, shape in numerical order. Finally, it comes to an conclusion that the fruit size, shape and leaf size, shape follow the correlation of linear statistical distribution, that the fruit size, shape, mass and the leaf size, shape show high linear correlations and that fruit distribution can be predicted through the analysis on the growth state of leaves.
语种：
英文
展开
A Novel 2-D Graphical Representation for DNA Sequences Based on the Chemical Properties
作者：
Liu, Yuewu;Peng, Yan*
期刊：
Journal of Computational and Theoretical Nanoscience ,2013年10(9):2102-2105 ISSN：1546-1955
通讯作者：
Peng, Yan
作者机构：
[Liu, Yuewu] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Peng, Yan] Hunan Agr Univ, Crop Gene Engn Key Lab Hunan Prov, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Peng, Yan] H;Hunan Agr Univ, Crop Gene Engn Key Lab Hunan Prov, Changsha 410128, Hunan, Peoples R China.
关键词：
DNA Sequence;Graphical Representation;Numerical Characterization
摘要：
Based on the chemical properties, sixteen combinations are obtained. By allocating these combinations to sixteen different two-component vectors respectively in the Cartesian coordinate system, we present a novel 2-D graphical representation of DNA primary sequences, which can offer more biology information. This approach is not any circuit and has one to one correspondence between DNA sequences and DNA graphs. The examination of similarities/ dissimilarities among the coding sequences of the first exon of --globin gene of different species illustrates the utility of the approach. ©2013 American Scientific Publishers. All rights reserved.
语种：
英文
展开
Temperature effects on growth configurations of Al atoms on an Fe rhombohedron: a molecular dynamics simulation
作者：
Yang, Jianyu* ;Hu, Wangyu;Tang, Jianfeng;Dai, Xiongying
期刊：
Journal of Nanoparticle Research ,2013年15(6):1-7 ISSN：1388-0764
通讯作者：
Yang, Jianyu
作者机构：
[Yang, Jianyu] Hunan Inst Engn, Xiangtan 411104, Peoples R China.;[Dai, Xiongying; Hu, Wangyu] Hunan Univ, Dept Appl Phys, Changsha 410082, Hunan, Peoples R China.;[Tang, Jianfeng] Hunan Agr Univ, Dept Appl Phys, Changsha 410028, Hunan, Peoples R China.
通讯机构：
[Yang, Jianyu] H;Hunan Inst Engn, Xiangtan 411104, Peoples R China.
关键词：
Structure of nanoparticle;Metals and alloys;Growth from solid phases;Molecular dynamics
摘要：
The growth of Al atoms on an Fe rhombohedral nanoparticle with 1,105 atoms in the temperature range of 100–1,200 K is studied by molecular dynamics and embedded atom method. Several thermodynamics parameters, including potential energy, radial distribution function, and Lindemann index are used for the growth process analysis. This study reports an increasing energy per Fe atom and a decreasing energy per Al atom with increasing temperature. Alloying between Fe and Al atoms accelerates at higher temperatures, because of the incorporation of more Al atoms into the Fe core. Three different growth configurations are found for the simulations at different temperatures. At temperatures below 800 K, the core–shell configuration with Fe and Al as core and shell, respectively, is the most favorable. At approximately 800 K, a nanoparticle with surface alloying order is formed. Finally, surface melting occurs at growth temperatures higher than 900 K.
语种：
英文
展开
Kinetics of lipase recovery from the aqueous phase of biodiesel production by macroporous resin adsorption and reuse of the adsorbed lipase for biodiesel preparation
作者：
Zhao, Xuebing* ;Fan, Ming;Zeng, Jing;Du, Wei;Liu, Canming;...
期刊：
Enzyme and Microbial Technology ,2013年52(4-5):226-233 ISSN：0141-0229
通讯作者：
Zhao, Xuebing
作者机构：
[Zeng, Jing; Zhao, Xuebing; Liu, Dehua; Du, Wei] Tsinghua Univ, Dept Chem Engn, Inst Appl Chem, Beijing 100084, Peoples R China.;[Liu, Canming; Fan, Ming] Hunan Agr Univ, Coll Sci, Changsha 410028, Hunan, Peoples R China.
通讯机构：
[Zhao, Xuebing] T;Tsinghua Univ, Dept Chem Engn, Inst Appl Chem, Beijing 100084, Peoples R China.
关键词：
Adsorption;Aqueous phase;Biodiesel;Enzymatic transesterification;Free lipase;Macroporous resin
摘要：
A commercial macroporous resin (D3520) was screened for lipase recovery by adsorption from the aqueous phase of biodiesel production. The influences of several factors on the adsorption kinetics were investigated. It was found that the kinetic behavior of lipase adsorption by macroporous resin could be well described by pseudo-first-order model. Temperature had no significant effects on lipase adsorption, while resin-to-protein ratio (R) significantly affected both rate constant (k1) and equilibrium adsorption capacity (Qe). No lipase was adsorbed when mixing (shaking) was not performed; however, protein recovery reached 98% after the adsorption was conducted at 200rpm for 5h in a shaker. The presence of methanol and glycerol showed significant negative influence on lipase adsorption kinetics. Particularly, increasing glycerol concentration could dramatically decrease k1 but not impact Qe. Biodiesel was found to dramatically decrease Qe even present at a concentration as low as 0.02%, while k1 was found to increase with biodiesel concentration. The adsorbed lipase showed a relatively stable catalytic activity in tert-butanol system, but poor stability in solvent-free system when used for biodiesel preparation. Oil and biodiesel were also found to adsorb onto resin during transesterification in solvent-free system. Therefore, the resin had to be washed by anhydrous methanol before re-used for lipase recovery. © 2013 Elsevier Inc.
语种：
英文
展开
Room temperature synthesis of Cu nanocages through Ni-induced electroless process
作者：
Zhao, Yan;Zhao, Jingzhe* ;Su, Zhaohong;Ma, Dechong;Hao, Xinli;...
期刊：
Colloids and Surfaces A: Physicochemical and Engineering Aspects ,2013年431:60-65 ISSN：0927-7757
通讯作者：
Zhao, Jingzhe
作者机构：
[Zhao, Jingzhe; Lu, Yan; Zhao, Yan; Guo, Jingnan; Hao, Xinli] Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.;[Su, Zhaohong] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Ma, Dechong] Shanxi Transportat Res Inst, Taiyuan 030006, Peoples R China.
通讯机构：
[Zhao, Jingzhe] H;Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.
关键词：
Ni-induced mechanism;Non-enzymatic sensor;Octahedral Cu nanocages
摘要：
Designed octahedral Cu nanocages were successfully prepared at room temperature by introducing Ni induced electroless strategy. This strategy balanced the inhibitory effect of sodium oleate (SOA) in the room temperature reduction process. Reduction rate was markedly improved as Ni2+ increasing. The Ni-induced electroless Cu deposition mechanism was studied. The first deposited metallic Ni particles catalyzed the oxidation of hydrazine (N2H4·H2O) to give electrons. Cu2O intermediates captured the electrons and were reduced to Cu nanocages with SOA existence. Thermo-gravimetric and differential thermal analysis (TG-DTA) results illuminated that the Ni-induced Cu nanocages had higher oxidation resistance property in air atmosphere compared to Cu nanocages prepared without Ni inclusion. A well-defined, stable and fast amperometric response of glucose was observed when the Ni-induced Cu nanocages were constructed as non-enzymatic glucose sensor. © 2013 Elsevier B.V.
语种：
英文
展开
Epoxidation of cyclohexene with O-2 over the composite catalysts of Mn-montmorillonite coordinated with novel Schiff-base ligands
作者：
Peng, Yu;Li, Zhongying;Tang, Ruiren*
期刊：
RSC Advances ,2013年3(43):19965-19970 ISSN：2046-2069
通讯作者：
Tang, Ruiren
作者机构：
[Peng, Yu] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Li, Zhongying; Tang, Ruiren] Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Tang, Ruiren] C;Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.
摘要：
The catalytic activity of the heterogeneous catalysts of Mn-mont (where mont represents montmorillonite) coordinated with Schiff-base ligands for epoxidation of cyclohexene by O<inf>2</inf> under Mukaiyama conditions was studied. The catalysts were characterized by IR, UV-vis DRS, XRD, SEM and ICP. The heterogeneous catalysts were proved to promote the epoxidation of cyclohexene efficiently, the effects of various reaction conditions on the catalytic reaction were optimized and obtained as high as 100% conversion with 90.0% selectivity of epoxycyclohexane at 40 °C in 5 h with molecular oxygen as oxidant in acetonitrile. Repeated runs indicated that the catalysts were stable for at least 3 cycles. Thus, the heterogeneous catalysts of Mn-mont coordinated with Schiff-base ligands were proved to be environmentally friendly and economical for the epoxidation of cyclohexene. ©The Royal Society of Chemistry 2013.
语种：
英文
展开
Amperometric determination of ascorbic acid using multiwalled carbon nanotube-thiolated polyaniline composite modified glassy carbon electrode
作者：
Liu, Ying;Su, Zhaohong;Zhang, Yi;Chen, Li;Gu, Tiean;...
期刊：
Journal of Electroanalytical Chemistry ,2013年709:19-25 ISSN：1572-6657
通讯作者：
Xie, Qingji
作者机构：
[Huang, Siyu; Liu, Yan; Liu, Ying; Xie, Qingji; Gu, Tiean; Zhang, Yi; Sun, Lingen; Chen, Li; Yao, Shouzhuo] Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ China, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410087, Hunan, Peoples R China.;[Su, Zhaohong] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Xie, Qingji] H;Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ China, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410087, Hunan, Peoples R China.
关键词：
Amperometric sensing of ascorbic acid;Electroactive nanocomposite of thiolated polyaniline at neutral pH;Mercaptosuccinic acid;Multiwalled carbon nanotubes;Polyaniline
摘要：
A new nanocomposite film that is highly electroactive in neutral aqueous solutions was prepared based on multiwalled carbon nanotubes (MWCNTs), polyaniline (PANI) and mercaptosuccinic acid (MSA). Briefly, a glassy carbon electrode (GCE) was firstly cast-coated with MWCNTs (MWCNTs/GCE), PANI was then electrodeposited on MWCNTs/GCE, and finally MSA was tethered to the electrooxidized PANI via the thiol-ene reaction to form MSA-PANI/MWCNTs/GCE. Electrochemical quartz crystal microbalance, scanning electron microscopy, Fourier transform infrared spectroscopy and electrochemical impedance spectroscopy were used for film characterization and process monitoring. The high electroactivity of MSA-PANI/MWCNTs/GCE observed in neutral aqueous solutions is ascribed to the anionic MSA tethered to the PANI backbones as well as the good conductivity and high specific surface area of MWCNTs. The prepared MSA-PANI/MWCNTs/GCE electrode was successfully used for catalytic electroanalysis of ascorbic acid (AA) at neutral pH. Under optimum conditions, the anodic amperometric detection of AA provides a wide linear detection range (20 μM-29.6 mM), a high sensitivity (363 μA mM<sup>-1</sup> cm <sup>-2</sup>) and a low limit of detection (0.6 μM, S/N = 3) as well as good reproducibility and stability, which are superior to many reported AA electrochemical sensors. ©2013 Elsevier B.V. All rights reserved.
语种：
英文
展开
Effect of surfactants on fabricating CuO nanoleaves and Cu nanocages at room temperature
作者：
Zhao, Yan;Zhao, Jingzhe* ;Su, Zhaohong;Hao, Xinli;Ma, Dechong;...
期刊：
Colloids and Surfaces A: Physicochemical and Engineering Aspects ,2013年436:34-40 ISSN：0927-7757
通讯作者：
Zhao, Jingzhe
作者机构：
[Zhao, Jingzhe; Lu, Yan; Zhao, Yan; Guo, Jingnan; Hao, Xinli] Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.;[Su, Zhaohong] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Ma, Dechong] Shanxi Transportat Res Inst, Taiyuan 030006, Peoples R China.
通讯机构：
[Zhao, Jingzhe] H;Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.
关键词：
Cu nanocages;CuO nanoleaves;Non-enzymatic sensor;Surfactant
摘要：
Typical surfactants, cetyltrimethylammonium bromide (CTAB), poly(vinyl pyrrolidone) (PVP) and sodium oleate (SOA), were employed to investigate their effect on fabricating CuO nanoleaves and Cu nanocages at room temperature. Comparing with the system without surfactant, adding surfactant could improve the monodispersity of CuO nanoleaves. The obtained CuO nanoleaves were further reduced to Cu nanocages. CTAB performed few effects on the reduction process. PVP accelerated the reducing velocity, while SOA had inhibitory effect on the reaction. The reaction activities of the obtained Cu nanocages with and without surfactants were characterized by thermo-gravimetric and differential thermal analysis (TG-DTA), and the sequence of activity with oxygen is PVP-assisted Cu. >. SOA-assisted Cu. >. CTAB-assisted Cu. >. Cu without surfactant. The obtained Cu nanocages were also used to construct non-enzymatic glucose sensors. The electrodes modified by PVP- and SOA-assisted Cu had relative higher sensitivity than the others. © 2013 Elsevier B.V.
语种：
英文
展开
Additive-free solvothermal synthesis of hierarchical flower-like LiFePO4/C mesocrystal and its electrochemical performance
作者：
Zhou, Nan;Uchaker, Evan;Wang, Hai-Yan;Zhang, Ming;Liu, Su-Qin;...
期刊：
RSC Advances ,2013年3(42):19366-19374 ISSN：2046-2069
通讯作者：
Li, Huiyong
作者机构：
[Wu, Xiongwei; Zhou, Nan; Li, Huiyong] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Cao, Guozhong; Uchaker, Evan; Zhou, Nan; Zhang, Ming] Univ Washington, Dept Mat Sci & Engn, Seattle, WA 98195 USA.;[Wang, Hai-Yan; Liu, Su-Qin; Liu, You-Nian; Zhou, Nan] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Li, Huiyong] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
摘要：
Three dimensional hierarchical flower-like lithium iron phosphate (LiFePO<inf>4</inf>) mesocrystals were successfully synthesized via a solvothermal approach with the utilization of a mixture of water/ethylene glycol/dimethylacetamide (H<inf>2</inf>O/EG/DMAC) as co-solvent. No other surfactant or template agent was used and beautiful micro-sized LiFePO <inf>4</inf> mesoporous structures with a special rose-like morphology were obtained. The hierarchical LiFePO<inf>4</inf> mesocrystals were assembled by well crystallized nano-sized LiFePO<inf>4</inf> thin plates with a thickness around 100 nm. The characteristics and electrochemical dynamics as well as performance of the obtained hierarchical flower-like LiFePO<inf>4</inf> mesocrystals were carefully investigated. The flower-like hierarchical LiFePO<inf>4</inf> mesocrystals showed a high initial lithium intercalation capability of 147 mA h g<sup>-1</sup> at a current density of 17 mA g <sup>-1</sup> (0.1 C), which should be attributed to the high specific surface area resulting from the mesoporous superstructure and well crystallized LiFePO<inf>4</inf> nano-plate composition units. Polyvinylpyrrolidone (PVP) was introduced during the solvothermal synthesis as an in situ carbon coating source. The obtained flower-like C-coated LiFePO<inf>4</inf> mesocrystals exhibited even better initial lithium intercalation capability of 161 mA h g<sup>-1</sup> at 0.1 C and showed improved lithium storage performance at high rates as well as good cyclic stability. ©2013 The Royal Society of Chemistry.
语种：
英文
展开
Simplified Simultaneous Determination of Concentrations of V2+, V3+ and V4+: An Example of Inverse Problems
作者：
Li, H. Y.;Yamamura, T.;Ohta, S.;Gao, C.;Xiang, X. J.;...
期刊：
Asian Journal of Chemistry ,2013年25(5):2821-2828 ISSN：0970-7077
通讯作者：
Zhou, K. C.
作者机构：
[Xia, Y. F.; Gao, C.; Zhou, K. C.; Liu, J. W.; Liu, S. Q.; Wu, X. W.; Li, H. Y.] Cent S Univ, Sch Chem & Chem Engn, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.;[Jin, M.; Wu, X. W.; Li, H. Y.; Xiang, X. J.] Hunan Agr Univ, Sch Sci, Changsha 410128, Hunan, Peoples R China.;[Li, D. X.; Ohta, S.; Wu, X. W.; Yamamura, T.] Tohoku Univ, Inst Mat Res, Sendai, Miyagi 9808577, Japan.
通讯机构：
[Zhou, K. C.] C;Cent S Univ, Sch Chem & Chem Engn, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
关键词：
Spectrophotometry;Singular value decomposition;Least-squares method;Vanadium Redox-flow battery
摘要：
A simplified spectrophotometric method was developed for the simultaneous determination, of concentrations (C-n) of Vanadium ions at, different oxidation states, Which has applications in Vanadium redox-flow batteries. This method is of particular use for mixed V3+/VO2+ and V2+/V3+ Solutions. A singular value decomposition Was applied to spectra to resolve the severe overlaps of spectra of these cations and to obtain. the selected wavelength lambda(k). By using absorbance obtained at,the selected Wavelength:in the single- and mixd-valence solutions, the coefficient matrices G = [g(k), n] were determined:1;LT the least squares Method. The determined formulae are: C-n = Sigma(k=1)gk, nI(k), where I-k is the absorbance at lambda(1)=520 nm, lambda(2)=401 nm, lambda(3)=770 nm or lambda(4)=320 nm. The determined concentrations agree well (within 5%) with those determined using other methods.
语种：
英文
展开
SiO2 capsulized Cu active nanoparticles: Synthesis and activity study
作者：
Zhao, Yan;Zhao, Jingzhe* ;Su, Zhaohong;Hao, Xinli;Li, Yawen;...
期刊：
Journal of Materials Chemistry A ,2013年1(27):8029-8036 ISSN：2050-7488
通讯作者：
Zhao, Jingzhe
作者机构：
[Zhao, Jingzhe; Li, Na; Li, Yawen; Zhao, Yan; Hao, Xinli] Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.;[Su, Zhaohong] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Li, Yunling] Henan Inst Sci & Technol, Coll Chem & Chem Engn, Xinxiang 453003, Peoples R China.
通讯机构：
[Zhao, Jingzhe] H;Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.
摘要：
Cu active nanoparticles (Cu ANPs) were synthesized in weakly acidic solution to preserve their catalytic activity. SiO<inf>2</inf> capsules were designed to insulate Cu ANPs from oxidation. The weak interaction between SiO<inf>2</inf> capsules and Cu ANPs ensured that the designed nanoparticles had good anti-oxidation property and potentially high activity. The increased anti-oxidation property with thicker SiO<inf>2</inf> capsules (Cu<inf>s3</inf> >Cu<inf>s2</inf> >Cu<inf>s1</inf>) and the order of reactivity to oxygen (Cu<inf>s1</inf> = Cu<inf>s2</inf> >Cu<inf>s3</inf>) showed that Cu ANPs with SiO<inf>2</inf> capsules (Cu<inf>s2</inf>) of appropriate thickness would be the best for application. By using the samples to construct non-enzymatic sensors, the detected activity toward electro-catalytic oxidation of glucose confirmed this conclusion. Dehiscence of SiO<inf>2</inf> capsules recovered the activity of the Cu ANPs in the catalytic ammonium perchlorate (AP) decomposition process. With the addition of 1.5% of Cu ANPs, the high temperature decomposition of AP decreased by 184.2°C. ©2013 The Royal Society of Chemistry.
语种：
英文
展开
A dynamical atomic simulation for the NiAl Wulff nanoparticle
作者：
Tang, Jianfeng;Yang, Jianyu*
期刊：
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY ,2013年536:318-322 ISSN：1386-1425
通讯作者：
Yang, Jianyu
作者机构：
[Tang, Jianfeng] Hunan Agr Univ, Dept Appl Phys, Changsha 410128, Hunan, Peoples R China.;[Yang, Jianyu] Hunan Inst Engn, Xiangtan 411104, Peoples R China.
通讯机构：
[Yang, Jianyu] H;Hunan Inst Engn, Xiangtan 411104, Peoples R China.
关键词：
Crystal growth;Diffusion in nanoscale solids;Metals and alloys;Structure of nanoparticles
摘要：
Ni - Al bimetallic nanoparticle structures are studied from a kinetic point of view. The diffusion and growth of Ni (or Al) atoms on Al (or Ni) cores with the Wulff structure are simulated by molecular dynamics and nudged elastic band methods. An analytic embedded atom model is applied to the two metals. The energy barriers of several typical diffusion processes of the adatoms on the nanoparticle surface are calculated. Results show that the incorporation of the Ni atoms into the Al core easily occurs, and the reverse process does not readily proceed. The growth simulations reveal that a better core-shell nanoparticle is obtained when the Al atoms are deposited on the Ni core at lower temperatures, and the deposition of the Ni atoms on the Al core leads to an amorphous surface. (C) 2013 Elsevier B.V. All rights reserved.
语种：
英文
展开
Leaf image segmentation method based on multifractal detrended fluctuation analysis
作者：
Wang, Fang;Li, Jin-Wei* ;Shi, Wen;Liao, Gui-Ping
期刊：
Journal of Applied Physics ,2013年114(21):214905 ISSN：0021-8979
通讯作者：
Li, Jin-Wei
作者机构：
[Shi, Wen; Wang, Fang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liao, Gui-Ping; Li, Jin-Wei; Wang, Fang] Hunan Agr Univ, Agr Informat Inst, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Li, Jin-Wei] H;Hunan Agr Univ, Agr Informat Inst, Changsha 410128, Hunan, Peoples R China.
关键词：
crops;fuzzy set theory;image segmentation;pattern clustering
摘要：
To identify singular regions of crop leaf affected by diseases, based on multifractal detrended fluctuation analysis (MF-DFA), an image segmentation method is proposed. In the proposed method, first, we defend a new texture descriptor: local generalized Hurst exponent, recorded as LHq based on MF-DFA. And then, box-counting dimension f(LHq) is calculated for sub-images constituted by the LHq of some pixels, which come from a specific region. Consequently, series of f(LHq) of the different regions can be obtained. Finally, the singular regions are segmented according to the corresponding f(LHq). Six kinds of corn diseases leaf's images are tested in our experiments. Both the proposed method and other two segmentation methods—multifractal spectrum based and fuzzy C-means clustering have been compared in the experiments. The comparison results demonstrate that the proposed method can recognize the lesion regions more effectively and provide more robust segmentations.
语种：
英文
展开
Adsorption of methylene blue onto humic acid-coated Fe3O4 nanoparticles
作者：
Zhang, Xian;Zhang, Panyue* ;Wu, Zhen;Zhang, Ling;Zeng, Guangming;...
期刊：
Colloids and Surfaces A: Physicochemical and Engineering Aspects ,2013年435:85-90 ISSN：0927-7757
通讯作者：
Zhang, Panyue
作者机构：
[Zhang, Xian] Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.;[Zeng, Guangming; Zhang, Panyue; Wu, Zhen] Hunan Univ, Minist Educ, Key Lab Environm Biol & Pollut Control, Changsha 410082, Hunan, Peoples R China.;[Zhang, Ling] Hunan Univ, Coll Civil Engn, Changsha 410082, Hunan, Peoples R China.;[Zhou, Chunjiao] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Zhang, Panyue] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Zhang, Panyue] H;Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.
会议名称：
7th International Conference on Interfaces Against Pollution (IAP)
会议时间：
JUN 11-14, 2012
会议地点：
Nancy, FRANCE
会议主办单位：
[Zhang, Xian] Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.^[Zhang, Panyue;Wu, Zhen;Zeng, Guangming] Hunan Univ, Minist Educ, Key Lab Environm Biol & Pollut Control, Changsha 410082, Hunan, Peoples R China.^[Zhang, Ling] Hunan Univ, Coll Civil Engn, Changsha 410082, Hunan, Peoples R China.^[Zhou, Chunjiao] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Humic acid;Fe3O4 nanoparticles;Adsorption;Methylene blue;Desorption
摘要：
Humic acid-coated Fe3O4 (HA-Fe3O4) nanoparticles as magnetic adsorbents were prepared with co-precipitation of humic acids and Fe3O4 nanoparticles. TEM analysis indicated that the average diameter of the spherical HA-Fe3O4 core was about 15nm. TGA characterization showed that the HA-Fe3O4 nanoparticles contained about 50% (w/w) HA. The characteristic absorption of HA at 1604/cm and 1701/cm was observed in the FIRT spectra of HA-Fe3O4 nanoparticles. The HA-Fe3O4 nanoparticles exhibited a typical superparamagnetic characteristic with a saturation magnetization of 77emu/g, which resulted in an easy solid-liquid separation with an external magnet. The HA-Fe3O4 nanoparticles were applied for methylene blue (MB) adsorption and results showed that the HA-Fe3O4 nanoparticles possessed much higher adsorbed amount of MB than the bare Fe3O4 nanoparticles and HA powders. The HA-Fe3O4 nanoparticles remained stable in a broad pH range of 3-11. The adsorption kinetics can be described by a pseudo-second-order equation, and the time when 50% of the MB was adsorbed (t1/2) was 7min. The adsorption isotherm of the HA-Fe3O4 nanoparticles agreed well with Langmuir adsorption equation, and the maximum adsorbed amount of MB was 0.291mmol/g. Desorption of the saturated HA-Fe3O4 nanoparticles was easily carried out with a mixture of methanol and acetic acid with a volume ratio of 9:1. © 2013 Elsevier B.V.
语种：
英文
展开
