Chemical Ordering and Surface Segregation in Cu-Pt Nanoalloys: The Synergetic Roles in the Formation of Multishell Structures
WOS被引频次：13
SCI-E EI
作者：
Tang, Jianfeng;Deng, Lei* ;Xiao, Shifang;Deng, Huiqiu;Zhang, Xingming;Hu, Wangyu
期刊：
Journal of Physical Chemistry C ,2015年119(37):21515-21527 ISSN：1932-7447
通讯作者：
Deng, Lei
作者机构：
[Tang, Jianfeng; Hu, Wangyu] Hunan Univ, Coll Mat Sci & Engn, Changsha 411182, Hunan, Peoples R China.;[Xiao, Shifang; Deng, Huiqiu] Hunan Univ, Sch Phys & Elect, Changsha 411182, Hunan, Peoples R China.;[Deng, Lei; Tang, Jianfeng; Zhang, Xingming] Hunan Agr Univ, Dept Appl Phys, Changsha 411128, Hunan, Peoples R China.
通讯机构：
[Deng, Lei] Hunan Agr Univ, Dept Appl Phys, Changsha 411128, Hunan, Peoples R China.
摘要：
We performed Monte Carlo simulations coupled with MAEAM potentials to study the surface segregation and chemical ordering patterns in Cu-Pt nanoalloy particles for a broad range of sizes, shapes, composition, and temperature. It was found that both the Cu segregation on the surface and the chemical ordering in the core are the general rules and usually compete with each other. Surface segregation of Cu is enhanced with increasing particle size or surface openness or global Cu composition. Despite their different morphologies, most of the types of ordered phases in the core region are the same as bulk alloys. Due to the modification or suppression effects of surface segregation, the degrees of chemical ordering shift to the Pt-richer side and are more apparent in a large-sized particle. Particularly, at a narrow composition range, the multishell structures (onion-ring or multishell/maze-like core) form in (truncated) octahedrons, illustrating a subtle synergy between the segregated Cu {111} facets and the L1<inf>1</inf>ordering. The possibility and advantage of transformation from these multishell structures to Pt multilayer shell/single Cu-rich core ORR catalysts by selective etching of Cu were also discussed. ©2015 American Chemical Society.
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英文
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An acid-free rechargeable battery based on PbSO4 and spinel LiMn2O4
WOS被引频次：13
SCI-E
作者：
Liu, Yu;Wen, Zubiao* ;Wu, Xiongwei;Wang, Xiaowei;Wu, Yuping;Holze, Rudolf
期刊：
Chemical communications (Cambridge, England) ,2014年50(89):13714-13717 ISSN：1359-7345
通讯作者：
Wen, Zubiao
作者机构：
[Liu, Yu; Wu, Xiongwei; Wu, Yuping] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Yu; Wen, Zubiao] Jiangxi Normal Univ, Coll Chem & Chem Engn, Nanchang 330022, Peoples R China.;[Liu, Yu; Holze, Rudolf] Tech Univ Chemnitz, Inst Chem, AG Elektrochem, D-09107 Chemnitz, Germany.;[Wang, Xiaowei; Wu, Yuping] Fudan Univ, Dept Chem, New Energy & Mat Lab, Shanghai 200433, Peoples R China.;[Wang, Xiaowei; Wu, Yuping] Fudan Univ, Shanghai Key Lab Mol Catalysis & Innovat Mat, Shanghai 200433, Peoples R China.
通讯机构：
[Wen, Zubiao] Jiangxi Normal Univ, Coll Chem & Chem Engn, Nanchang 330022, Peoples R China.
摘要：
An acid-free lead rechargeable battery system comprising PbSO4 as the negative electrode, LiMn2O4 as the positive electrode and a neutral Li2SO4 aqueous solution as electrolyte is reported and its electrochemical performance is very good. It shows great promise to reduce the global use of lead by 50% since it is also low cost. This journal is © the Partner Organisations 2014.
语种：
英文
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Aqueous Rechargeable Batteries for Large-scale Energy Storage
WOS被引频次：13
SCI-E
作者：
Liu, Jun;Hu, Junping;Deng, Qi;Mo, Jun;Xie, Hao;Liu, Zaichun;Xiong, Yuanfu;Wu, Xiongwei* ;Wu, Yuping
期刊：
Israel Journal of Chemistry ,2015年55(5):521-536 ISSN：0021-2148
通讯作者：
Wu, Xiongwei
作者机构：
[Xiong, Yuanfu; Xie, Hao; Liu, Zaichun; Hu, Junping; Wu, Xiongwei; Mo, Jun; Wu, Yuping; Deng, Qi; Liu, Jun] Hunan Agr Univ, Coll Sci, Changsha, Hunan, Peoples R China.;[Hu, Junping; Wu, Yuping; Liu, Jun] Nanjing Tech Univ, Coll Energy, Nanjing 211816, Jiangsu, Peoples R China.
通讯机构：
[Wu, Xiongwei] Hunan Agr Univ, Coll Sci, Changsha, Hunan, Peoples R China.
关键词：
aqueous rechargeable batteries;electrochemical performance;electrochemistry;energy densities;environmental chemistry
摘要：
The depletion of fossil fuels and environmental pollution provide an increasing requirement for rechargeable batteries with high energy densities, high efficiency, and excellent cycling performance. Aqueous rechargeable batteries (ARBs), with the merits of safety, low-cost, super-fast charge-discharge ability, and environmental friendliness, are one of the most competitive technologies for large-scale energy systems. Recently, extensive efforts have been dedicated to enhancing their electrochemical performance, and great breakthroughs have been achieved, especially for aqueous rechargeable lithium batteries (ARLBs), including three generations of ARLBs, aqueous rechargeable sodium batteries (ARSBs), and redox flow batteries (RFBs). Herein, the latest advances on their critical components are reviewed, and challenges and further directions are also pointed out. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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英文
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Time-Domain ab lnitio Analysis Rationalizes the Unusual Temperature Dependence of Charge Carrier Relaxation in Lead Halide Perovskite
WOS被引频次：13
SCI-E
作者：
Li, Wei* ;Tang, Jianfeng;Casanova, David;Prezhdo, Oleg V.*
期刊：
ACS ENERGY LETTERS ,2018年3(11):2713-2720 ISSN：2380-8195
通讯作者：
Li, Wei;Prezhdo, Oleg V.
作者机构：
[Tang, Jianfeng; Li, Wei] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Casanova, David] DIPC, Donostia San Sebastian 20018, Euskadi, Spain.;[Casanova, David] IKERBASQUE, Basque Fdn Sci, Bilbao 48013, Euskadi, Spain.;[Prezhdo, Oleg V.] Univ Southern Calif, Dept Chem, Los Angeles, CA 90089 USA.
通讯机构：
[Li, Wei] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Prezhdo, Oleg V.] Univ Southern Calif, Dept Chem, Los Angeles, CA 90089 USA.
摘要：
Increased charge carrier lifetimes at elevated temperatures constitute an intriguing and valuable feature of hybrid organic inorganic perovskites that are subject to heating in solar energy applications. We rationalize this peculiar behavior at the atomistic level using real-time time dependent density functional theory and nonadiabatic molecular dynamics. Focusing on tetragonal MAPbI(3), we demonstrate that temperature has different effects on the organic and inorganic subsystems and leads to subtle structural changes, decreasing nonradiative electron hole recombination. First, charge-phonon interactions are decreased because the libration dynamics of the organic component at higher temperature reduces the oscillation amplitude of the Pb-I lattice that supports electrons and holes. Second, thermal disorder localizes wave functions, reducing the nonadiabatic charge phonon coupling. Third, tilting of the inorganic octahedra increases the bandgap, extending charge carrier lifetime further. The detailed time-domain atomistic analysis of the uncommon dependence of charge recombination on temperature emphasizes the key role played by the organic cation, establishes important structure property relationships, provides valuable insights into efficient performance of perovskite solar cells, and highlights factors required to maintain and improve such performance.
语种：
英文
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Graphene supported nitrogen-doped porous carbon nanosheets derived from zeolitic imidazolate framework for high performance supercapacitors
WOS被引频次：13
SCI-E EI
作者：
Gan, Qingmeng;Liu, Suqin* ;Zhao, Kuangmin;Wu, Yuanzhan;He, Zhen;Zhou, Zhi
期刊：
RSC Advances ,2016年6(82):78947-78953 ISSN：2046-2069
通讯作者：
Liu, Suqin
作者机构：
[Gan, Qingmeng; He, Zhen; Liu, Suqin; Wu, Yuanzhan; Zhao, Kuangmin] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Zhou, Zhi] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Liu, Suqin] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.
摘要：
A nitrogen-doped porous carbon nanosheet/graphene composite (NPCN/G) with layer-by-layer structure is facilely synthesized on a large scale via pyrolysis of a zeolitic imidazolate framework (ZIF-8)/graphene (2D) mixture. The as-prepared NPCN/G owns a high Brunauer-Emmett-Teller (BET) specific surface area (1210 m<sup>2</sup>g<sup>-1</sup>) and nitrogen content (6.1%). The specific capacitance of NPCN/G in 6 M KOH solution reaches 306.4 F g<sup>-1</sup>at a current density of 0.2 A g<sup>-1</sup>. Moreover, NPCN/G exhibits an outstanding cycle stability with 97.4% capacitance preservation after 3500 cycles at a current density of 5 A g<sup>-1</sup>. Compared to the nitrogen-doped porous carbon nanosheets (NPCN), NPCN/G shows a higher capacitance and a superior cycle stability which can be ascribed to the synergistic effect between the GO nanosheets and carbon nanosheets. In addition, the specific capacitance of NPCN/G enhances with increasing concentration of electrolyte. ©2016 The Royal Society of Chemistry.
语种：
英文
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Dibromocarbene modified graphene: Preparation, characterization and its application in removal of pb(II) from aqueous solutions
WOS被引频次：13
SCI-E EI
作者：
Teng, Jie;Zeng, Xiang;Yue, Bao-Yu;Zhao, Xiu-Hui;Wang, Zhi-Hang;Yu, Jin-Gang* ;Xu, Xuan-Ming;Zhong, Ming* ;Wu, Xiong-Wei;Zhou, Wen-Xin;Zhou, Zhi
期刊：
Nanoscience and Nanotechnology Letters ,2016年8(3):226-231 ISSN：1941-4900
通讯作者：
Yu, Jin-Gang;Zhong, Ming
作者机构：
[Zeng, Xiang; Teng, Jie] Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China.;[Xu, Xuan-Ming; Yue, Bao-Yu; Zhao, Xiu-Hui; Yu, Jin-Gang; Wang, Zhi-Hang] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Zhong, Ming] Hunan Inst Sci & Technol, Sch Chem & Chem Engn, Yueyang 414006, Hunan, Peoples R China.;[Zhou, Wen-Xin; Wu, Xiong-Wei; Yu, Jin-Gang; Zhou, Zhi] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Yu, Jin-Gang] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Zhong, Ming] Hunan Inst Sci & Technol, Sch Chem & Chem Engn, Yueyang 414006, Hunan, Peoples R China.;[Yu, Jin-Gang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Graphene Nanosheets;Dibromocarbene;Functionalization;Characterization
摘要：
In this study, a novel graphene-based composite, dibromocarbene modified graphene (Gr-CBr<inf>2</inf>), was successfully synthesized by a simple cycloaddition procedure. The obtained composite was fully characterized by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, highresolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS). The adsorption properties of Gr-CBr<inf>2</inf>for Pb(II) ions from aqueous solutions were evaluated. The experimental data fitted well to the Langmuir isotherm. And a maximum adsorption capacity of 49.46 mg g<sup>-1</sup>was obtained for Gr-CBr<inf>2</inf>at 298 K, which was around 19 times higher than that (mg g<sup>-1</sup>) of as-received graphene. The results indicated that Gr-CBr<inf>2</inf>may be used as an efficient adsorbent for the removal of Pb(II) from aqueous solutions Copyright ©2016 American Scientific Publishers.
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英文
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A simple and sensitive electrochemical immunosensor based on thiol aromatic aldehyde as a substrate for the antibody immobilization
WOS被引频次：13
SCI-E EI Medline
作者：
Shen, Youming* ;Zhang, Youyu;Liu, Meiling;Liu, Xiaoyin;Guo, Huan;Zhang, Xiangyang;Zhang, Chunxiang;Li, Haitao;Yao, Shouzhuo
期刊：
Talanta ,2015年141:288-292 ISSN：0039-9140
通讯作者：
Shen, Youming
作者机构：
[Shen, Youming; Zhang, Youyu; Liu, Meiling; Li, Haitao; Guo, Huan; Yao, Shouzhuo] Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.;[Shen, Youming; Zhang, Xiangyang; Zhang, Chunxiang] Hunan Univ Arts & Sci, Coll Chem & Chem Engn, Changde 415000, Peoples R China.;[Liu, Xiaoyin] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Shen, Youming] Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.
关键词：
Synthesis;Thiol aromatic aldehyde;Antibody immobilization;Electrochemical immunosensor;Human IgG
摘要：
In this work, a novel sulfur-containing compound with aldehyde groups was synthesized, which was used to immobilize antibodies through the covalent bonding of the aldehyde groups with amino groups, in which no additional chemical cross-linker is required. Human IgG was used as a model analyte to fabricate the electrochemical immunosensor. Using the proposed immunosensor, IgG was detected within the range from 0.01 to 25 ng mL<sup>-1</sup>with a detection limit of 0.003 ng mL<sup>-1</sup>obtained by 3 S/N. The simple electrochemical immunosensor had a good specificity, stability and reproducibility. ©2015 Elsevier B.V. All rights reserved.
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英文
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Quantifying the Degree of Aggregation from Fluorescent Dye-Conjugated DNA Probe by Single Molecule Photobleaching Technology for the Ultrasensitive Detection of Adenosine
WOS被引频次：12
SCI-E EI Medline
作者：
Shi, Xingbo* ;He, Yu;Gao, Wenli;Liu, Xiaoying;Ye, Zhongju;Liu, Hua;Xiao, Lehui*
期刊：
Analytical Chemistry ,2018年90(6):3661-3665 ISSN：0003-2700
通讯作者：
Shi, Xingbo;Xiao, Lehui
作者机构：
[Shi, Xingbo; Gao, Wenli; He, Yu] Hunan Agr Univ, Coll Food Sci & Technol, Hunan Prov Key Lab Food Sci & Biotechnol, Changsha 410128, Hunan, Peoples R China.;[Shi, Xingbo] Hunan Univ, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Liu, Hua; Ye, Zhongju; Xiao, Lehui] Nankai Univ, Coll Chem, Tianjin Key Lab Biosensing & Mol Recognit, State Key Lab Med Chem Biol, Tianjin 300071, Peoples R China.;[Liu, Xiaoying] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Shi, Xingbo] Hunan Agr Univ, Coll Food Sci & Technol, Hunan Prov Key Lab Food Sci & Biotechnol, Changsha 410128, Hunan, Peoples R China.;[Shi, Xingbo] Hunan Univ, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Xiao, Lehui] Nankai Univ, Coll Chem, Tianjin Key Lab Biosensing & Mol Recognit, State Key Lab Med Chem Biol, Tianjin 300071, Peoples R China.
摘要：
In this work, we demonstrated a single molecule photobleaching-based strategy for the ultrasensitive detection of adenosine. A modified split aptamer was designed to specifically recognize individual adenosine molecules in solution. The specific binding of dye-labeled short strand DNA probes onto the elongated aptamer strand in the presence of adenosine resulted in a concentration-dependent self-aggregation process. The degree-of-aggregation (DOA) of the short DNA probes on the elongated aptamer strand could then be accurately determined based on the single molecule photobleaching measurement. Through statistically analyzing the DOA under different target concentrations, a well-defined curvilinear relationship between the DOA and target molecule concentration (e.g., adenosine) was established. The limit-of-detection (LOD) is down to 44.5 pM, which is lower than those recently reported results with fluorescence-based analysis. Owing to the high sensitivity and excellent selectivity, the sensing strategy described herein would find broad applications in biomolecule analysis under complicated surroundings.<br/> ©2018 American Chemical Society.
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英文
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Local multifractal detrended fluctuation analysis for non-stationary image's texture segmentation
WOS被引频次：12
SCI-E EI
作者：
Wang, Fang* ;Li, Zong-shou;Li, Jin-wei
期刊：
Applied Surface Science ,2014年322:116-125 ISSN：0169-4332
通讯作者：
Wang, Fang
作者机构：
[Wang, Fang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Li, Zong-shou] Jishou Univ, Coll Informat Sci & Engn, Jishou 416000, Peoples R China.;[Li, Jin-wei] Hunan Agr Univ, Agr Informat Inst, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Wang, Fang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Image stationarity;Local multifractal detrended fluctuation analysis;Local generalized Hurst exponent;Image segmentation;Noise
摘要：
Feature extraction plays a great important role in image processing and pattern recognition. As a power tool, multifractal theory is recently employed for this job. However, traditional multifractal methods are proposed to analyze the objects with stationary measure and cannot for non-stationary measure. The works of this paper is twofold. First, the definition of stationary image and 2D image feature detection methods are proposed. Second, a novel feature extraction scheme for non-stationary image is proposed by local multifractal detrended fluctuation analysis (Local MF-DFA), which is based on 2D MF-DFA. A set of new multifractal descriptors, called local generalized Hurst exponent (Lh<inf>q</inf>) is defined to characterize the local scaling properties of textures. To test the proposed method, both the novel texture descriptor and other two multifractal indicators, namely, local Hölder coefficients based on capacity measure and multifractal dimension D<inf>q</inf> based on multifractal differential box-counting (MDBC) method, are compared in segmentation experiments. The first experiment indicates that the segmentation results obtained by the proposed Lh<inf>q</inf> are better than the MDBC-based D<inf>q</inf> slightly and superior to the local Hölder coefficients significantly. The results in the second experiment demonstrate that the Lh<inf>q</inf> can distinguish the texture images more effectively and provide more robust segmentations than the MDBC-based D<inf>q</inf> significantly.
语种：
英文
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Kinetics of lipase recovery from the aqueous phase of biodiesel production by macroporous resin adsorption and reuse of the adsorbed lipase for biodiesel preparation
WOS被引频次：12
SCI-E EI Medline
作者：
Zhao, Xuebing* ;Fan, Ming;Zeng, Jing;Du, Wei;Liu, Canming;Liu, Dehua
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] Tsinghua Univ, Dept Chem Engn, Inst Appl Chem, Beijing 100084, Peoples R China.
关键词：
Biodiesel;Enzymatic transesterification;Free lipase;Aqueous phase;Macroporous resin;Adsorption
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 (k<inf>1</inf>) and equilibrium adsorption capacity (Q<inf>e</inf>). 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 k<inf>1</inf> but not impact Q<inf>e</inf>. Biodiesel was found to dramatically decrease Q<inf>e</inf> even present at a concentration as low as 0.02%, while k<inf>1</inf> 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
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Global existence and optimal L-2 decay rate for the strong solutions to the compressible fluid models of Korteweg type
WOS被引频次：12
SCI-E
作者：
Tan, Zhong;Wang, Huaqiao* ;Xu, Jiankai
期刊：
Journal of Mathematical Analysis and Applications ,2012年390(1):181-187 ISSN：0022-247X
通讯作者：
Wang, Huaqiao
作者机构：
[Wang, Huaqiao; Tan, Zhong] Xiamen Univ, Sch Math Sci, Xiamen 361005, Peoples R China.;[Xu, Jiankai] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Wang, Huaqiao] Xiamen Univ, Sch Math Sci, Xiamen 361005, Peoples R China.
关键词：
Compressible Navier-Stokes-Korteweg system;Energy estimates;Optimal decay rates;Strong solution
摘要：
In this paper, we consider the compressible Navier-Stokes-Korteweg system that models the motions of the compressible isothermal viscous capillary fluids. We prove the global existence of a strong solution to the compressible Navier-Stokes-Korteweg system when the initial perturbation lips parallel to rho(0) - (rho) over cap parallel to(H2) + parallel to u(0)parallel to(H1) is small. Furthermore, if the L-1 norm of the initial perturbation is finite, we can obtain the optimal L-2 decay rates. (C) 2012 Elsevier Inc. All rights reserved.
语种：
英文
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Periodic and subharmonic solutions for fourth-order nonlinear difference equations
WOS被引频次：12
SCI-E EI
作者：
Liu, Xia;Zhang, Yuanbiao;Shi, Haiping* ;Deng, Xiaoqing
期刊：
Applied Mathematics and Computation ,2014年236:613-620 ISSN：0096-3003
通讯作者：
Shi, Haiping
作者机构：
[Liu, Xia] Hunan Agr Univ, Oriental Sci & Technol Coll, Changsha 410128, Hunan, Peoples R China.;[Liu, Xia] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Zhang, Yuanbiao] Jinan Univ, Packaging Engn Inst, Zhuhai 519070, Peoples R China.;[Shi, Haiping] Guangdong Construct Vocat Technol Inst, Modern Business & Management Dept, Guangzhou 510450, Guangdong, Peoples R China.;[Deng, Xiaoqing] Hunan Univ Commerce, Sch Math & Stat, Changsha 410205, Hunan, Peoples R China.
通讯机构：
[Shi, Haiping] Guangdong Construct Vocat Technol Inst, Modern Business & Management Dept, Guangzhou 510450, Guangdong, Peoples R China.
关键词：
Periodic and subharmonic solutions;Fourth-order;Nonlinear difference equations;Discrete variational theory
摘要：
By using the critical point theory, some new criteria are obtained for the existence and multiplicity of periodic and subharmonic solutions to fourth-order nonlinear difference equations. The main approach used in our paper is a variational technique and the Linking Theorem. Our results generalize and improve the existing ones. ©2014 Elsevier B.V. All rights reserved.
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英文
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Direct Synthesis of Primary Anilines via Nickel-mediated C(sp(2))-H Aminations
WOS被引频次：12
SCI-E
作者：
Yu, Lin;Chen, Xiang;Liu, Da;Hu, Liang;Yu, Yongqi;Huang, Hang;Tan, Ze* ;Gui, Qingwen*
期刊：
Advanced Synthesis and Catalysis ,2018年360(7):1346-1351 ISSN：1615-4150
通讯作者：
Tan, Ze;Gui, Qingwen
作者机构：
[Liu, Da; Tan, Ze; Hu, Liang; Yu, Lin; Huang, Hang; Yu, Yongqi; Chen, Xiang] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Gui, Qingwen] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Tan, Ze] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Gui, Qingwen] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
C-H activation;primary aniline;nickel salt;sodium azide;anthranilic acid
摘要：
An efficient and mild protocol for the direct conversion of arene C−H bonds to C−NH 2 without the need for extra deprotection step has been established, and to the best of our knowledge, this is the first time that the synthesis of primary anilines via nickel-mediated C(sp 2 )-H activations has been reported. This approach utilizes 8-aminoquinoline as the directing group and sodium azide, a cheap and commercially available material, as the nitrogen source. In addition, the reaction is highly selective, affording the mono-ortho-aminated benzamides only. The reaction tolerates a broad range of substrates with diverse functional groups and the corresponding ortho-aminated benzamides were efficiently synthesized in 41–82% yields. (Figure presented.). © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
语种：
英文
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One pot synthesis of nitrogen-doped hollow carbon spheres with improved electrocatalytic properties for sensitive H 2 O 2 sensing in human serum
WOS被引频次：11
SCI-E EI
作者：
Peng, Chang;Zhou, Suya;Zhang, Xuemei;Zeng, Tianqin;Zhang, Wei;Li, Hongmei;Liu, Xiaoying* ;Zhao, Peng*
期刊：
Sensors and Actuators, B: Chemical ,2018年270:530-537 ISSN：0925-4005
通讯作者：
Liu, Xiaoying;Zhao, Peng
作者机构：
[Liu, Xiaoying; Peng, Chang; Zhang, Wei; Zhou, Suya; Zhang, Xuemei; Zeng, Tianqin] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Li, Hongmei; Zhao, Peng] Southern Med Univ, Sch Pharmaceut Sci, Guangzhou Key Lab Drug Res Emerging Virus Prevent, Guangdong Prov Key Lab New Drug Screening, 1838 Guangzhou Ave North, Guangzhou 510515, Guangdong, Peoples R China.
通讯机构：
[Liu, Xiaoying] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Zhao, Peng] Southern Med Univ, Sch Pharmaceut Sci, Guangzhou Key Lab Drug Res Emerging Virus Prevent, Guangdong Prov Key Lab New Drug Screening, 1838 Guangzhou Ave North, Guangzhou 510515, Guangdong, Peoples R China.
关键词：
N-doped hollow carbon spheres;One pot synthesis;Electrical catalyst;H2O2;Human serum samples
摘要：
N-doped hollow carbon spheres (N-HCS) have been proved as efficient electrical catalytic materials with outstanding oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) ability. However, conventional approaches for the synthesis of N-HCS always involved multistep procedures. In this paper, by appropriately controlling the polymerization of tetraethoxysilane (TEOS) and resorcinol/formaldehyde (RF), N-HCS have been synthesized through “one pot”method without use of surfactant. Next, the ORR and OER of N-HCS were conducted to examine its electrocatalytic ability. Finally, it was modified on the glassy carbon electrode (GCE) as an improved electrical catalyst to monitor H<inf>2</inf>O<inf>2</inf>in human serum samples. The linear ranges for monitoring H<inf>2</inf>O<inf>2</inf>were from 0.05 mM to 29.5 mM and from 29.5 mM to 47.5 mM with a limit of detection of 0.02 mM. The recoveries for the assays in human serums were between 92.5% and 107.4%. Therefore, we believe that this newly synthesized N-HCS will play a significant role in the synthesis and application of electrocatalytic materials and the development of novel electrochemical sensors.<br/> ©2018 Elsevier B.V.
语种：
英文
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Multifractal detrended fluctuation analysis for image texture feature representation
WOS被引频次：11
SCI-E EI
作者：
Wang, Fang;Li, Zong-Shou* ;Liao, Gui-Ping
期刊：
International Journal of Pattern Recognition and Artificial Intelligence ,2014年28(3) ISSN：0218-0014
通讯作者：
Li, Zong-Shou
作者机构：
[Wang, Fang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liao, Gui-Ping; Wang, Fang] Hunan Agr Univ, Agr Informat Inst, Changsha 410128, Hunan, Peoples R China.;[Li, Zong-Shou] Jishou Univ, Coll Informat Sci & Engn, Jishou 416000, Peoples R China.
通讯机构：
[Li, Zong-Shou] Jishou Univ, Coll Informat Sci & Engn, Jishou 416000, Peoples R China.
关键词：
Texture feature;blur;compression;multifractal analysis;multifractal detrended fluctuation analysis;noise
摘要：
Multifractal theory has been widely used in different kinds of fields. In this paper, methods were proposed to extract two kinds of multifractal descriptors of gray series and two-dimensional surfaces for gray image based on the multifractal detrended fluctuation analysis. The proposed multifractal parameters can be well described by texture feature through the test of some textures. Three aspects of experiments have been conducted to verify the robustness of the proposed parameters, which include noise immunity, degree of image blurring and compression ratio. Comparisons were conducted between the proposed parameters and other kinds of texture feature parameters calculated by the standard multifractal analysis, the method of differential box counting and the methods of gray level co-occurrence matrix. Results demonstrate that the proposed exponents of H(2) and h(2) have great noise immunity and are robust to image compression and blurring. ©2014 World Scientific Publishing Company.
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英文
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Reactions of 2-aza-21-carbaporphyrin with aniline derivatives
WOS被引频次：11
ESI高被引 SCI-E
作者：
Ren, Demin;Liu, Bin;Li, Xiaofang* ;Koniarz, Sebastian;Pawlicki, Milosz;Chmielewski, Piotr J.*
期刊：
Organic Chemistry Frontiers ,2019年6(7):908-918 ISSN：2052-4129
通讯作者：
Li, Xiaofang;Chmielewski, Piotr J.
作者机构：
[Ren, Demin] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Bin; Li, Xiaofang] Hunan Univ Sci & Technol, Sch Chem & Chem Engn, Minist Educ, Key Lab Theoret Organ Chem & Funct Mol, Xiangtan 411201, Hunan, Peoples R China.;[Koniarz, Sebastian; Pawlicki, Milosz; Chmielewski, Piotr J.] Univ Wroclaw, Dept Chem, F Joliot Curie 14, PL-50383 Wroclaw, Poland.
通讯机构：
[Li, Xiaofang] Hunan Univ Sci & Technol, Sch Chem & Chem Engn, Minist Educ, Key Lab Theoret Organ Chem & Funct Mol, Xiangtan 411201, Hunan, Peoples R China.;[Chmielewski, Piotr J.] Univ Wroclaw, Dept Chem, F Joliot Curie 14, PL-50383 Wroclaw, Poland.
摘要：
Regioselective azotization or bis(amination) products of the title porphyrinoid were achieved in one-pot one-step syntheses under mild conditions using a selection of aromatic amines and isoamyl nitrite or p-chloranil, respectively. Structures, tautomery, chirality as well as spectroscopic and redox properties of the new systems were discussed.
语种：
英文
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DNA-encoded signal conversion for sensitive microgravimetric detection of small molecule-protein interaction.
WOS被引频次：11
SCI-E Medline
作者：
Fei, Yue-Hua;Liu, Dengyou;Wu, Zai-Sheng* ;Shen, Guo-Li;Yu, Ru-Qin
期刊：
Bioconjugate chemistry ,2011年22(12):2369-2376 ISSN：1043-1802
通讯作者：
Wu, Zai-Sheng
作者机构：
[Shen, Guo-Li; Yu, Ru-Qin; Wu, Zai-Sheng; Fei, Yue-Hua] Hunan Univ, Chem & Chem Engn Coll, 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] Hunan Univ, Chem & Chem Engn Coll, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
摘要：
Identification and quantification of small organic molecules capable of binding to a protein of interest with reasonable affinity and specificity is a central problem. Via developing DNA-encoded recognizing probe, we validate a proof-of-principle for constructing of small target-to-DNA conversion that screens the small molecule-protein interaction. Successful identification of beta-indole acetic acid, abscisic acid, or 2,4-dichlorophenoxyacetic acid/corresponding antibody binding implies its fascinating potential for interrogating small molecule/protein interaction.
语种：
英文
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Analysis of speech signals' characteristics based on MF-DFA with moving overlapping windows
WOS被引频次：11
SCI-E EI
作者：
Zhao, Huan;He, Shaofang*
期刊：
Physica A: Statistical Mechanics and its Applications ,2016年442:343-349 ISSN：0378-4371
通讯作者：
He, Shaofang
作者机构：
[He, Shaofang; Zhao, Huan] Hunan Univ, Sch Informat Sci & Engn, Changsha 410082, Hunan, Peoples R China.;[He, Shaofang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[He, Shaofang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
MF-DFA;Speech signals;Multi-fractal characteristics
摘要：
In this paper, multi-fractal characteristics of speech signals are analyzed based on MF-DFA, and it is found that the multi-fractal features are influenced greatly by frame length and noise, besides, there is a little difference between them among speech frames. Secondly, motivated by framing and using frame shift to ensure the continuity and smooth transition of speech in speech signals processing, an advanced MF-DFA (MF-DFA with forward moving overlapping windows) is proposed. The length of moving overlapping windows is determined by parameter θ. Given the value of time scale s, we have MF-DFA with the maximum moving overlapping windows and MF-DFA with half overlapping windows when θ=1/s and θ=1/2 respectively. Moreover, when θ=1 we exactly have MF-DFA. Numerical experiments and analysis illustrate that the multi-fractal characteristics based on AMF-DFA outperform MF-DFA and MF-DMA in stability, noise immunity and discrimination. ©2015 Elsevier B.V. All rights reserved.
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英文
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Promising pyridinium ylide based anchors towards high-efficiency dyes for dye-sensitized solar cells applications: Insights from theoretical investigations
WOS被引频次：11
SCI-E EI
作者：
Lu, Teng-Fei;Li, Wei* ;Chen, Jie;Tang, Jianfeng;Bai, Fu-Quan;Zhang, Hong-Xing*
期刊：
Electrochimica Acta ,2018年283:1798-1805 ISSN：0013-4686
通讯作者：
Zhang, Hong-Xing;Li, Wei
作者机构：
[Bai, Fu-Quan; Lu, Teng-Fei; Zhang, Hong-Xing; Chen, Jie] Jilin Univ, Inst Theoret Chem, Lab Theoret & Computat Chem, Changchun 130023, Jilin, Peoples R China.;[Tang, Jianfeng; Li, Wei] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Zhang, Hong-Xing] Jilin Univ, Inst Theoret Chem, Lab Theoret & Computat Chem, Changchun 130023, Jilin, Peoples R China.;[Li, Wei] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Dye-sensitized solar cell;Density function theory;Charge transfer;Anchoring group;Organic dye
摘要：
We theoretically examine a series of anchors for dye-sensitized solar cells application, with particular attention was paid to the potential of novel pyridinium ylide based anchors. The geometrical structure, electronic property, and optical spectrum of the isolated dyes and its interface with TiO<inf>2</inf> are analyzed by using quantum chemistry calculations. Quantum dynamics simulation is performed to investigate the interface electron transfer process across the dye/TiO<inf>2</inf> interface. The key parameters influencing the short-circuit current and open-circuit voltage are calculated to quantify the performance of different dyes. Our results show that the pyridinium ylide based anchors benefit light-harvesting and improve intramolecular charge transfer character as well as shift up the conduction band edge of TiO<inf>2</inf> semiconductor which further increase short-circuit current and open-circuit voltage. Conjugated rhodanime-3-acetic anchor exhibits the enhanced electron injection than the non-conjugated structure due to the more significant donor-acceptor interaction. The simulation performed in this work demonstrates the potential of novel pyridinium ylide based anchors with respect to the traditional carboxylic acid and rhodanime-3-acetic based anchors, reveals the crucial role of local structure variation in the interface electron transfer, and finally guides the design of high-efficiency sensitizer for dye-sensitized solar cells application.<br/> ©2018 Elsevier Ltd
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英文
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Improved luminescence and energy-transfer properties of Ca14Al10Zn6O35:Ti4+,Mn4+ deep-red-emitting phosphors with high brightness for light-emitting diode (LED) plant-growth lighting
WOS被引频次：11
SCI-E
作者：
Zhou, Zhi;Li, Yiran;Xia, Mao* ;Zhong, Yuan;Zhou, Nan* ;Hintzen, H. T. (Bert)
期刊：
Dalton Transactions ,2018年47(38):13713-13721 ISSN：1477-9234
通讯作者：
Xia, Mao;Zhou, Nan
作者机构：
[Xia, Mao; Zhong, Yuan; Xia, M; Zhou, Nan; Zhou, Zhi; Li, Yiran] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Xia, Mao] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.;[Hintzen, H. T. (Bert)] Delft Univ Technol, Fac Appl Sci, Sect Fundamental Aspetts Mat & Energy, Grp Luminescent Mat, Delft, Netherlands.
通讯机构：
[Xia, M; Zhou, N] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Xia, Mao] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
摘要：
For plant-growth lighting, novel deep-red emission phosphors with high brightness were obtained by co-doping Ti4+ and Mn4+ into a Ca14Al10Zn6O35 substrate through a conventional solid-state reaction strategy. The nominal Ca14-(x+y)/2Al10-x-yZn6O35:xTi4+,yMn4+ (CAZO:Ti4+,Mn4+) phosphors could be excited by both near-ultraviolet (NUV) and blue-light-emitting diode (LED) chips efficiently and exhibited a strong deep-red emission band ranging from 650 nm to 750 nm, which should be the result of the 2E → 4A2 transition inside the [MnO6]8- octahedral. Multiple energy transfer from Ti4+ to Mn4+ was detected in this CAZO; whereby Ti4+ and Mn4+ phosphors were verified to be a result of the dipole-dipole interaction under excitation at 270 nm. LED plant-growth lights were fabricated using the as-prepared nominal Ca13.825Al9.65Zn6O35:0.15Mn4+,0.2Ti4+,0.005H3BO3 (CAZO:Mn4+,Ti4+,H3BO3) phosphors pumped by a 460 nm blue-chip; this luminaire could be used to greatly promote the cultivation of succulent plants. Combined with the attractive thermal stability as well as high quantum efficiency (QE) of this phosphor, it was demonstrated that these novel phosphors may be candidate deep-red luminescent materials for LED plant lighting. © 2018 The Royal Society of Chemistry.
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英文
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