Highly sensitive and selective colorimetric and off-on fluorescent chemosensor for Cu^{2+} in aqueous solution and living cells
WOS被引频次：345
ESI高被引 SCI-E EI Medline
作者：
Zhao, Yan;Zhang, Xiao-Bing;Han, Zhi-Xiang;Qiao, Li;Li, Chun-Yan;Jian, Li-Xin;Shen, Guo-Li;Yu, Ru-Qin
期刊：
Analytical chemistry ,2009年81(16):7022-7030 ISSN：0003-2700
通讯作者：
Zhang, X.-B.(xbzhang@hnu.cn)
作者机构：
[Shen, Guo-Li; Zhang, Xiao-Bing; Yu, Ru-Qin; Han, Zhi-Xiang; Qiao, Li; Zhao, Yan; Jian, Li-Xin] State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China;[Li, Chun-Yan] Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan, 411105, China
通讯机构：
[Zhang, Xiao-Bing] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
关键词：
Aqueous solutions - Chemosensor - Detection limits - Direct measurement - Environmental Monitoring - Experimental conditions - Fluorescence intensities - Fluorescence quenching - Fluorescent detection - Fluorescent response - High concentration - Highly sensitive - Living cell - Paramagnetic nature - Ring opening - River water samples - Signal changes - Strong binding
摘要：
The design and synthesis of a novel rhodamine spirolactam derivative and its application in fluorescent detections of Cu<sup>2+</sup>in aqueous solution and living cells are reported. The signal change of the chemosensor is based on a specific metal ion induced reversible ring-opening mechanism of the rhodamine spirolactam. It exhibits a highly sensitive "turn-on" fluorescent response toward Cu<sup>2+</sup> in aqueous solution with an 80-fold fluorescence intensity enhancement under 10 equiv of Cu<sup>2+</sup>added. This indicates that the synthesized chemosensor effectively avoided the fluorescence quenching for the paramagnetic nature of Cu<sup>2+</sup> via its strong binding capability toward Cu<sup>2+</sup>. With the experimental conditions optimized, the probe exhibits a dynamic response range for Cu<sup>2+</sup> from 8.0 ×10 <sup>-7</sup> to 1.0 ×10<sup>-5</sup> M, with a detection limit of 3.0 ×10<sup>-7</sup> M. The response of the chemosensor for Cu<sup>2+</sup> is instantaneous and reversible. Most importantly, both the color and fluorescence changes of the chemosensor are remarkably specific for Cu <sup>2+</sup> in the presence of other heavy and transition metal ions (even those that exist in high concentration), which meet the selective requirements for biomedical and environmental monitoring application. The proposed chemosensor has been used for direct measurement of Cu<sup>2+</sup> content in river water samples and imaging of Cu<sup>2+</sup> in living cells with satisfying results, which further demonstrates its value of practical applications in environmental and biological systems. ©2009 American Chemical Society.
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Broadband nonlinear optical response in multi-layer black phosphorus: an emerging infrared and mid-infrared optical material
WOS被引频次：291
ESI高被引 SCI-E EI
作者：
Lu, S. B.;Miao, L. L.;Guo, Z. N.;Qi, X.;Zhao, C. J.;Zhang, H.;Wen, S. C.;Tang, D. Y.;Fan, D. Y.
期刊：
Optics Express ,2015年23(9):11183-11194 ISSN：1094-4087
通讯作者：
Zhang, H
作者机构：
[Fan, D. Y.; Guo, Z. N.; Zhao, C. J.; Lu, S. B.; Zhang, H.] Shenzhen Univ, Minist Educ & Guangdong Prov, Coll Optoelect Engn, SZU NUS Collaborat Innovat Ctr Optoelect Sci, Shenzhen 518060, Peoples R China.;[Fan, D. Y.; Guo, Z. N.; Zhao, C. J.; Lu, S. B.; Zhang, H.] Shenzhen Univ, Coll Optoelect Engn, Minist Educ & Guangdong Prov, Key Lab Optoelect Devices & Syst, Shenzhen 518060, Peoples R China.;[Tang, D. Y.] Nanyang Technol Univ, Sch Elect & Elect Engn, Singapore 639798, Singapore.;[Wen, S. C.; Zhao, C. J.; Miao, L. L.] Hunan Univ, Coll Phys & Microelect Sci, Minist Educ, Key Lab Micronano Optoelect Devices, Changsha 410082, Hunan, Peoples R China.;[Qi, X.] Xiangtan Univ, Lab Quantum Engn & Micronano Energy Technol, Xiangtan 411105, Hunan, Peoples R China.
通讯机构：
[Zhang, H.] Shenzhen Univ, Minist Educ & Guangdong Prov, Coll Optoelect Engn, SZU NUS Collaborat Innovat Ctr Optoelect Sci, Shenzhen 518060, Peoples R China.
关键词：
Layered semiconductors - Light-matter interactions - Non-linear optical material - Nonlinear optical response - Optical applications - Saturable absorption - Thermodynamically stable - Ultra-fast photonics
摘要：
Black phosphorous (BP), the most thermodynamically stable allotrope of phosphorus, is a high-mobility layered semiconductor with direct band-gap determined by the number of layers from 0.3 eV (bulk) to 2.0 eV (single layer). Therefore, BP is considered as a natural candidate for broadband optical applications, particularly in the infrared (IR) and mid-IR part of the spectrum. The strong light-matter interaction, narrow direct band-gap, and wide range of tunable optical response make BP as a promising nonlinear optical material, particularly with great potentials for infrared and mid-infrared opto-electronics. Herein, we experimentally verified its broadband and enhanced saturable absorption of multi-layer BP (with a thickness of similar to 10 nm) by wide-band Z-scan measurement technique, and anticipated that multi-layer BPs could be developed as another new type of two-dimensional saturable absorber with operation bandwidth ranging from the visible (400 nm) towards mid-IR (at least 1930 nm). Our results might suggest that ultra-thin multi-layer BP films could be potentially developed as broadband ultra-fast photonics devices, such as passive Q-switcher, mode-locker, optical switcher etc. (C) 2015 Optical Society of America
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英文
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Band structure engineering of graphene by strain: First-principles calculations
WOS被引频次：285
ESI高被引 SCI-E
作者：
Gui, Gui;Li, Jin;Zhong, Jianxin
期刊：
PHYSICAL REVIEW B ,2008年78(7) ISSN：1098-0121
通讯作者：
Zhong, JX
作者机构：
[Zhong, Jianxin] Xiangtan Univ, Lab Quantum Engn & Micronano Energy Technol, Xiangtan 411105, Hunan, Peoples R China.;Xiangtan Univ, Dept Phys, Xiangtan 411105, Hunan, Peoples R China.
通讯机构：
[Zhong, Jianxin] Xiangtan Univ, Lab Quantum Engn & Micronano Energy Technol, Xiangtan 411105, Hunan, Peoples R China.
摘要：
We have investigated the electronic structure of graphene under different planar strain distributions using the first-principles pseudopotential plane-wave method and the tight-binding approach. We found that graphene with a symmetrical strain distribution is always a zero band-gap semiconductor and its pseudogap decreases linearly with the strain strength in the elastic regime. However, asymmetrical strain distributions in graphene result in opening of band gaps at the Fermi level. For the graphene with a strain distribution parallel to C-C bonds, its band gap continuously increases to its maximum width of 0.486 eV as the strain increases up to 12.2%. For the graphene with a strain distribution perpendicular to C-C bonds, its band gap continuously increases only to its maximum width of 0.170 eV as the strain increases up to 7.3%. The anisotropic nature of graphene is also reflected by different Poisson ratios under large strains in different directions. We found that the Poisson ratio approaches to a constant of 0.1732 under small strains but decreases differently under large strains along different directions.
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英文
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Nonlocal Cauchy problem for fractional evolution equations
WOS被引频次：270
ESI高被引 SCI-E EI
作者：
Zhou, Yong;Jiao, Feng
期刊：
Nonlinear Analysis: Real World Applications ,2010年11(5):4465-4475 ISSN：1468-1218
通讯作者：
Zhou, Y
作者机构：
[Zhou, Yong; Jiao, Feng] Department of Mathematics, Xiangtan University, Xiangtan, Hunan 411105, China
通讯机构：
[Zhou, Yong] Xiangtan Univ, Dept Math, Xiangtan 411105, Hunan, Peoples R China.
关键词：
Evolution equations - Fractional evolution equations - Mild solution - Nonlocal Cauchy problem - Probability densities - Semi-group
摘要：
In this paper, the nonlocal Cauchy problem is discussed for the fractional evolution equations in an arbitrary Banach space and various criteria on the existence and uniqueness of mild solutions are obtained. An example to illustrate the applications of main results is also given. ©2009 Elsevier Ltd. All rights reserved.
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英文
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Existence of mild solutions for fractional neutral evolution equations
WOS被引频次：254
ESI高被引 SCI-E EI
作者：
Zhou, Yong
（ 周勇 ） ;Jiao, Feng
期刊：
Computers and Mathematics with Applications ,2010年59(3):1063-1077 ISSN：0898-1221
通讯作者：
Zhou, Y.(yzhou@xtu.edu.cn)
作者机构：
[Zhou, Yong; Jiao, Feng] Department of Mathematics, Xiangtan University, Xiangtan, Hunan 411105, China
通讯机构：
[Zhou, Yong] Xiangtan Univ, Dept Math, Xiangtan 411105, Hunan, Peoples R China.
关键词：
Analytic semigroup - Fractional neutral evolution equations - Mild solution - Neutral evolution - Nonlocal Cauchy problem - Probability densities
摘要：
In this paper, by using the fractional power of operators and some fixed point theorems, we discuss a class of fractional neutral evolution equations with nonlocal conditions and obtain various criteria on the existence and uniqueness of mild solutions. In the end, we give an example to illustrate the applications of the abstract results. ©2009 Elsevier Ltd. All rights reserved.
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英文
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A class of fractional evolution equations and optimal controls
WOS被引频次：221
ESI高被引 SCI-E EI
作者：
JinRong Wang;Yong Zhou
（ 周勇 ）
期刊：
Nonlinear Analysis: Real World Applications ,2011年12(1):262-272 ISSN：1468-1218
通讯作者：
Zhou, Y.(yzhou@xtu.edu.cn)
作者机构：
[Yong Zhou] Department of Mathematics, Xiangtan University, Xiangtan, Hunan 411105, China;[JinRong Wang] Department of Mathematics, Guizhou University, Guiyang, Guizhou 550025, China
通讯机构：
[Zhou, Yong] Xiangtan Univ, Dept Math, Xiangtan 411105, Hunan, Peoples R China.
关键词：
Fractional evolution equations;Analytic compact semigroup;Fractional power space;alpha-mild solutions;Optimal controls
摘要：
This paper concerns the existence of mild solutions for semilinear fractional evolution equations and optimal controls in the α-norm. A suitable α-mild solution of the semilinear fractional evolution equations is introduced. The existence and uniqueness of α-mild solutions are proved by means of fractional calculus, singular version Gronwall inequality and LeraySchauder fixed point theorem. The existence of optimal pairs of system governed by fractional evolution equations is also presented. Finally, an example is given for demonstration. ©2010 Published by Elsevier Ltd. All rights reserved.
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英文
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Preparation of nano-structured LiFePO4 /graphene composites by co-precipitation method
WOS被引频次：215
ESI高被引 SCI-E EI
作者：
Ding, Y.;Jiang, Y.;Xu, F.;Yin, J.;Ren, H.;Zhuo, Q.;Long, Z.;Zhang, P.
期刊：
ELECTROCHEMISTRY COMMUNICATIONS ,2010年12(1):10-13 ISSN：1388-2481
通讯作者：
Ding, Y
作者机构：
[Zhuo, Q.; Long, Z.; Zhang, P.; Xu, F.; Ding, Y.; Jiang, Y.; Yin, J.; Ren, H.] College of Civil Engineering and Mechanics, Xiangtan University, Hunan 411105, China;[Long, Z.; Zhang, P.; Xu, F.; Ding, Y.; Jiang, Y.; Yin, J.; Ren, H.] Institute of Rheology Mechanics, Xiangtan University, Hunan 411105, China
通讯机构：
[Ding, Y.] Xiangtan Univ, Inst Rheol Mech, Xiangtan 411105, Hunan, Peoples R China.
关键词：
Composite nanostructures - Conductivity limit - Coprecipitation method - Cycle performance - Electrical conductivity - Electrode material - Electronic conductivity - Galvanostatic charges - Graphenes - High surface area - LiFePO - Lithium secondary batteries - Nano-structured
摘要：
Graphene materials with superior electrical conductivities and high surface area would be advantageous for application in energy storage. And LiFePO<inf>4</inf> has been a promising electrode material however its poor conductivity limits its practical application. To improve the electronic conductivity, we prepare LiFePO<inf>4</inf>/graphene composites in a co-precipitation method, in which graphene nanosheets are used as additives. The composites were characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM), and their electrochemical properties were investigated by galvanostatic charge and discharge tests. The experimental results show that the capacity delivery and cycle performances of LiFePO<inf>4</inf> could be improved considerably by adding graphene. Therefore, LiFePO<inf>4</inf>/graphene composites are a promising candidate for lithium secondary batteries. ©2009 Elsevier B.V. All rights reserved.
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英文
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Ultra-short pulse generation by a topological insulator based saturable absorber
WOS被引频次：212
ESI高被引 SCI-E EI
作者：
Zhao, Chujun;Zhang, Han;Qi, Xiang;Chen, Yu;Wang, Zhiteng;Wen, Shuangchun;Tang, Dingyuan
期刊：
APPLIED PHYSICS LETTERS ,2012年101(21) ISSN：0003-6951
通讯作者：
Zhao, C.
作者机构：
[Qi, Xiang] Laboratory for Quantum Engineering and Micro-Nano Energy Technology, Faculty of Materials and Optoelectronic Physics, Xiangtan University, Xiangtan 411105, China;[Chen, Yu; Zhang, Han; Wen, Shuangchun; Wang, Zhiteng; Zhao, Chujun] Key Laboratory for Micro- and Nano-Optoelectronic Devices, Hunan University, Ministry of Education, Changsha 410082, China;[Tang, Dingyuan] School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China
通讯机构：
[Zhao, Chujun] Hunan Univ, Key Lab Micro & Nano Optoelect Devices, Minist Educ, Coll Phys & Microelect Sci, Changsha 410082, Hunan, Peoples R China.
关键词：
1550 nm - Optoelectronic properties - Passive mode - Saturable absorption - Telecommunication bands - Topological insulators - Ultra-fast photonics - Ultrafast pulse - Ultrashort pulse generation - Z-scan measurement
摘要：
Under strong laser radiation, a Dirac material, the topological insulator (TI) Bi<inf>2</inf>Te<inf>3</inf>, exhibits an optical transmittance increase as a result of saturable absorption. Based on an open-aperture Z-scan measurement at 1550 nm, we clearly show that the TI, Bi<inf>2</inf>Te<inf>3</inf> under our investigation, is indeed a very-high-modulation-depth (up to 95%) saturable absorber. Furthermore, a TI based saturable absorber device was fabricated and used as a passive mode locker for ultrafast pulse formation at the telecommunication band. This contribution unambiguously shows that apart from its fantastic electronic property, a TI (Bi<inf>2</inf>Te<inf>3</inf>) may also possess attractive optoelectronic property for ultrafast photonics. ©2012 American Institute of Physics.
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英文
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Density functional calculation of transition metal adatom adsorption on graphene
WOS被引频次：192
ESI高被引 SCI-E CPCI-S EI
作者：
Mao, Yuliang;Yuan, Jianmei;Zhong, Jianxin
期刊：
Journal of physics. Condensed matter : an Institute of Physics journal ,2008年20(11):115209 ISSN：0953-8984
通讯作者：
Mao, Y.(ylmao@xtu.edu.cn)
作者机构：
[Zhong, Jianxin; Mao, Yuliang] Institute for Quantum Engineering and Micro-Nano Energy Technology, Xiangtan University, Xiangtan 411105, Hunan, China;[Yuan, Jianmei] Hunan Key Laboratory for Computation and Simulation in Science and Engineering, School of Mathematics and Computational Science, Xiangtan University, 411105, Hunan, China
通讯机构：
[Mao, Yuliang] Xiangtan Univ, Inst Quantum Engn & Micro Nano Energy Technol, Xiangtan 411105, Peoples R China.
会议名称：
13th Conference on Liquid and Amorphous Metals
会议时间：
JUL 08-14, 2007
会议地点：
Ekaterinburg, RUSSIA
会议主办单位：
[Mao, Yuliang;Zhong, Jianxin] Xiangtan Univ, Inst Quantum Engn & Micro Nano Energy Technol, Xiangtan 411105, Peoples R China.^[Yuan, Jianmei] Xiangtan Univ, Sch Math & Computat Sci, Hunan Key Lab Computat & Simulat Sci & Engn, Xiangtan 411105, Peoples R China.
关键词：
Graphene - Transition metal adatom adsorption
摘要：
The functionalization of graphene (a single graphite layer) by the addition of transition metal atoms of Mn, Fe and Co to its surface has been investigated computationally using density functional theory. In the calculation, the graphene surface supercell was constructed from a single layer of graphite (0001) surface separated by vertical vacuum layers 2 nm thick. We found that the center of the hexagonal ring formed by carbon from graphene is the most stable site for Mn, Fe, Co to stay after optimization. The calculated spin-polarized band structures of the graphene encapsulating the Mn adatom indicate that the conduction bands are modified and move down due to the coupling between the Mn atom and graphene. For Fe adsorbed on the graphene surface, it is semi-half-metallic, and the spin polarization P is found to be 100%. The system of Co adatom on graphene exhibits metallic electronic structure due to the density of states (DOS) peak at the band center with both majority and minority spins. Local density of states analyses indicate a larger promotion of 4s electrons into the 3d state in Fe and Co, resulting in lower local moments compared to an Mn adatom on the graphite surface. ©IOP Publishing Ltd.
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英文
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Transition metal-catalyzed C-H functionalization of N-oxyenamine internal oxidants.
WOS被引频次：195
ESI高被引 SCI-E
作者：
Huang, Huawen;Ji, Xiaochen;Wu, Wanqing;Jiang, Huanfeng
期刊：
Chemical Society reviews ,2015年44(5):1155-1171 ISSN：0306-0012
通讯作者：
Jiang, HF
作者机构：
[Jiang, Huanfeng; Wu, Wanqing; Ji, Xiaochen; Huang, Huawen] S China Univ Technol, Sch Chem & Chem Engn, Guangzhou 510640, Guangdong, Peoples R China.;[Ji, Xiaochen; Huang, Huawen] Xiangtan Univ, Coll Chem, Minist Educ, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Peoples R China.
通讯机构：
[Jiang, Huanfeng] S China Univ Technol, Sch Chem & Chem Engn, Guangzhou 510640, Guangdong, Peoples R China.
摘要：
The transition metal-catalyzed C-H functionalization with hydroxylamine derivatives serving as both reactants and internal oxidants has attracted a lot of interest. These reactions obviate the need for external oxidants and therefore result in high reactivity and selectivity, as well as excellent functional group tolerance under mild reaction conditions, and moreover, water, methanol or carboxylic acid is generally released as the by-product, thus leading to reduced waste. This review focuses on the transition metal-catalyzed oxidative C-H functionalization of N-oxyenamine internal oxidants, with an emphasis on the scope and limitations, as well as the mechanisms of these reactions.
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英文
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Removal of hexavalent chromium [Cr(VI)] from aqueous solutions by the diatomite-supported/unsupported magnetite nanoparticles
WOS被引频次：185
ESI高被引 SCI-E EI Medline
作者：
Yuan, Peng* ;Liu, Dong;Fan, Mingde;Yang, Dan;Zhu, Runliang;Ge, Fei;Zhu, JianXi;He, Hongping
期刊：
Journal of hazardous materials ,2010年173(1-3):614-621 ISSN：0304-3894
通讯作者：
Yuan, Peng
作者机构：
[Yuan, Peng; Zhu, JianXi; Yang, Dan; Fan, Mingde; Liu, Dong; He, Hongping] Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China;[Zhu, Runliang; Ge, Fei] College of Chemical Engineering, Xiangtan University, Xiangtan, 411105, China;[Liu, Dong; Yang, Dan; Fan, Mingde] Graduate School, Chinese Academy of Sciences, Beijing, 100039, China
通讯机构：
[Yuan, Peng] Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
关键词：
Adsorption capacities - Adsorption data - Aqueous solutions - Average size - Coaggregation - Diatom shell - Diatomite - Electrostatic attractions - Elemental analysis - Hexavalent chromium - Langmuir isotherm - Magnetite nanoparticles - Nitrogen adsorption - Per unit - PH-dependent - Physicochemical process - Pseudo-second order model - Redox process - Thermally stable - Trivalent chromium
摘要：
Diatomite-supported/unsupported magnetite nanoparticles were prepared by co-precipitation and hydrosol methods, and characterized by X-ray diffraction, nitrogen adsorption, elemental analysis, differential scanning calorimetry, transmission electron microscopy and X-ray photoelectron spectroscopy. The average sizes of the unsupported and supported magnetite nanoparticles are around 25 and 15 nm, respectively. The supported magnetite nanoparticles exist on the surface or inside the pores of diatom shells, with better dispersing and less coaggregation than the unsupported ones. The uptake of hexavalent chromium [Cr(VI)] on the synthesized magnetite nanoparticles was mainly governed by a physico-chemical process, which included an electrostatic attraction followed by a redox process in which Cr(VI) was reduced into trivalent chromium [Cr(III)]. The adsorption of Cr(VI) was highly pH-dependent and the kinetics of the adsorption followed a pseudo-second-order model. The adsorption data of diatomite-supported/unsupported magnetite fit well with the Langmuir isotherm equation. The supported magnetite showed a better adsorption capacity per unit mass of magnetite than unsupported magnetite, and was more thermally stable than their unsupported counterparts. These results indicate that the diatomite-supported/unsupported magnetite nanoparticles are readily prepared, enabling promising applications for the removal of Cr(VI) from aqueous solution. ©2009 Elsevier B.V. All rights reserved.
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英文
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PEG modified BaGdF5 : Yb/Er nanoprobes for multi-modal upconversion fluorescent, in vivo X-ray computed tomography and biomagnetic imaging
WOS被引频次：164
ESI高被引 SCI-E EI
作者：
Zeng, Songjun;Tsang, Ming-Kiu;Chan, Chi-Fai;Wong, Ka-Leung;Hao, Jianhua
期刊：
BIOMATERIALS ,2012年33(36):9232-9238 ISSN：0142-9612
通讯作者：
Hao, J.(apjhhao@polyu.edu.hk)
作者机构：
[Zeng, Songjun; Chan, Chi-Fai; Tsang, Ming-Kiu; Hao, Jianhua] Department of Applied Physics and Materials Research Center, Hong Kong Polytechnic University, Hong Kong;[Wong, Ka-Leung; Chan, Chi-Fai] Department of Chemistry, Hong Kong Baptist University, Hong Kong;[Zeng, Songjun] Faculty of Materials, Optoelectronics and Physics, Key Lab. of Low-dimensional Materials and Application Technology, Ministry of Education, Xiangtan University, Xiangtan 411105, China
通讯机构：
[Hao, Jianhua] Hong Kong Polytech Univ, Dept Appl Phys, Hong Kong, Hong Kong, Peoples R China.
关键词：
Bio-imaging - Biomedical applications - Circulation time - Contrast agent - CT Image - HeLa cell - Hydrothermal methods - In-vivo - Magnetic applications - Magnetic imaging - Multi-functional - Multi-modal - Near Infrared - One pot - Paramagnetic properties - Up-conversion - Visible upconversion - X-ray computed tomography - X-ray tomography
摘要：
Herein, a multi-functional nanoprobe of polyethylene glycol (PEG) modified BaGdF<inf>5</inf>:Yb/Er upconversion nanoparticles (UCNPs) for tri-modal bioimaging of fluorescence, computed X-ray tomography (CT), and magnetic application is demonstrated for the first time. The PEG-modified BaGdF<inf>5</inf>:Yb/Er UCNPs with optimal small size were synthesized by a facile one-pot hydrothermal method. The as-designed single-phase nanoprobe presents near-infrared to visible upconversion emissions in UC fluorescent bioimaging of HeLa cell. Importantly, we have demonstrated in vivo CT images with enhanced signals of spleen of a mouse for 2 h, indicating the UCNPs can be successfully used as CT contrast agent for improving the detection of splenic diseases. In addition, these UCNPs also exhibit excellent intrinsic paramagnetic property which can be also for magnetic imaging. Therefore, our results indicate that a tri-modal nanoprobe served as fluorescent/CT/magnetic bioimaging can be realized using the PEG-modified BaGdF<inf>5</inf>:Yb/Er UCNPs with very low cytotoxicity and long circulation time, which would be very useful in a variety of biomedical application fields. ©2012 Elsevier Ltd.
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英文
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Existence of positive solutions of the boundary value problem for nonlinear fractional differential equations
WOS被引频次：160
ESI高被引 SCI-E EI
作者：
Li, C.F.;Luo, X.N.;Zhou, Yong
（ 周勇 ）
期刊：
Computers and Mathematics with Applications ,2010年59(3):1363-1375 ISSN：0898-1221
通讯作者：
Zhou, Y.(yzhou@xtu.edu.cn)
作者机构：
[Zhou, Yong; Li, C.F.; Luo, X.N.] Department of Mathematics, Xiangtan University, Hunan 411105, China
通讯机构：
[Zhou, Yong] Xiangtan Univ, Dept Math, Xiangtan 411105, Hunan, Peoples R China.
关键词：
Fixed point theorems - Fractional differential equations - Fractional order derivatives - Multiplicity results - Nonlinear differential equation - Odory conditions - Positive solution - Riemann-Liouville derivative
摘要：
In this paper, we are concerned with the nonlinear differential equation of fractional order D<inf>0 +</inf><sup>α</sup> u (t) + f (t, u (t)) = 0, 0 <t <1, 1 <α&le 2, where D<inf>0 +</inf><sup>α</sup> is the standard Riemann-Liouville fractional order derivative, subject to the boundary conditions u (0) = 0, D<inf>0 +</inf><sup>β</sup> u (1) = a D<inf>0 +</inf><sup>β</sup> u (ξ) . We obtain the existence and multiplicity results of positive solutions by using some fixed point theorems. ©2009 Elsevier Ltd. All rights reserved.
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英文
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Ultrasensitive and Broadband MoS2 Photodetector Driven by Ferroelectrics
WOS被引频次：152
ESI高被引 SCI-E EI
作者：
Wang, Xudong;Wang, Peng;Wang, Jianlu;Hu, Weida;Zhou, Xiaohao;Guo, Nan;Huang, Hai;Sun, Shuo;Shen, Hong;Lin, Tie;Tang, Minghua;Liao, Lei;Jiang, Anquan;Sun, Jinglan;Meng, Xiangjian;Chen, Xiaoshuang;Lu, Wei;Chu, Junhao
期刊：
Advanced materials (Deerfield Beach, Fla.) ,2015年27(42):6575-6581 ISSN：0935-9648
通讯作者：
Wang, JL
作者机构：
[Wang, Peng; Lu, Wei; Huang, Hai; Meng, Xiangjian; Chen, Xiaoshuang; Sun, Shuo; Shen, Hong; Chu, Junhao; Sun, Jinglan; Lin, Tie; Guo, Nan; Zhou, Xiaohao; Hu, Weida; Wang, Jianlu; Wang, Xudong] Chinese Acad Sci, Shanghai Inst Tech Phys, Natl Lab Infrared Phys, Shanghai 200083, Peoples R China.;[Jiang, Anquan] Fudan Univ, Dept Microelect, Shanghai 200433, Peoples R China.;[Tang, Minghua; Wang, Xudong] Xiangtan Univ, Sch Mat Sci & Engn, Xiangtan 411105, Hunan, Peoples R China.;[Wang, Jianlu] Chinese Acad Sci, Shanghai Inst Tech Phys, Natl Lab Infrared Phys, 500 Yu Tian Rd, Shanghai 200083, Peoples R China.;[Liao, Lei] Wuhan Univ, Dept Phys, Minist Educ, Wuhan 430072, Peoples R China.
通讯机构：
[Wang, Jianlu] Chinese Acad Sci, Shanghai Inst Tech Phys, Natl Lab Infrared Phys, 500 Yu Tian Rd, Shanghai 200083, Peoples R China.
关键词：
Detectivity - Ferroelectric polarization - Near Infrared - Photoresponse wavelength - photoresponsitivity - Poly(vinylidene fluoride-trifluoroethylene) - Ultra sensitives - Zero gate
摘要：
A few-layer MoS<inf>2</inf>photodetector driven by poly(vinylidene fluoride-trifluoroethylene) ferroelectrics is achieved. The detectivity and responsitivity are up to 2.2 ×10<sup>12</sup>Jones and 2570 A W<sup>-1</sup>, respectively, at 635 nm with ZERO gate bias. E<inf>g</inf>of MoS<inf>2</inf>is tuned by the ultrahigh electrostatic field from the ferroelectric polarization. The photoresponse wavelengths of the photodetector are extended into the near-infrared (0.85-1.55 μm). ©2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
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A grid-based evolutionary algorithm for many-objective optimization
WOS被引频次：151
ESI高被引 SCI-E EI
作者：
Yang, Shengxiang;Li, Miqing;Liu, Xiaohui;Zheng, Jinhua
期刊：
IEEE TRANSACTIONS ON EVOLUTIONARY COMPUTATION ,2013年17(5):721-736 ISSN：1089-778X
通讯作者：
Yang, SX
作者机构：
[Li, Miqing; Liu, Xiaohui] Department of Information Systems and Computing, Brunel University, Uxbridge, Middlesex UB8 3PH, United Kingdom;[Zheng, Jinhua] College of Information Engineering, Xiangtan University, Xiangtan 411105, China;[Yang, Shengxiang] School of Computer Science and Informatics, De Montfort University, Leicester LE1 9BH, United Kingdom
通讯机构：
[Yang, Shengxiang] De Montfort Univ, Sch Comp Sci & Informat, Leicester LE1 9BH, Leics, England.
关键词：
Convergence - Diversity - Evolutionary multiobjective optimization - Grid - Many-objective optimizations
摘要：
Balancing convergence and diversity plays a key role in evolutionary multiobjective optimization (EMO). Most current EMO algorithms perform well on problems with two or three objectives, but encounter difficulties in their scalability to many-objective optimization. This paper proposes a grid-based evolutionary algorithm (GrEA) to solve many-objective optimization problems. Our aim is to exploit the potential of the grid-based approach to strengthen the selection pressure toward the optimal direction while maintaining an extensive and uniform distribution among solutions. To this end, two concepts - grid dominance and grid difference - are introduced to determine the mutual relationship of individuals in a grid environment. Three grid-based criteria, i.e., grid ranking, grid crowding distance, and grid coordinate point distance, are incorporated into the fitness of individuals to distinguish them in both the mating and environmental selection processes. Moreover, a fitness adjustment strategy is developed by adaptively punishing individuals based on the neighborhood and grid dominance relations in order to avoid partial overcrowding as well as guide the search toward different directions in the archive. Six state-of-the-art EMO algorithms are selected as the peer algorithms to validate GrEA. A series of extensive experiments is conducted on 52 instances of nine test problems taken from three test suites. The experimental results show the effectiveness and competitiveness of the proposed GrEA in balancing convergence and diversity. The solution set obtained by GrEA can achieve a better coverage of the Pareto front than that obtained by other algorithms on most of the tested problems. Additionally, a parametric study reveals interesting insights of the division parameter in a grid and also indicates useful values for problems with different characteristics. ©1997-2012 IEEE.
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英文
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Existence and uniqueness for fractional neutral differential equations with infinite delay
WOS被引频次：142
ESI高被引 SCI-E EI
作者：
Zhou, Yong;Jiao, Feng;Li, Jing
期刊：
Nonlinear Analysis, Theory, Methods and Applications ,2009年71(7-8):3249-3256 ISSN：0362-546X
通讯作者：
Zhou, Y.(yzhou@xtu.edu.cn)
作者机构：
[Zhou, Yong; Jiao, Feng; Li, Jing] Department of Mathematics, Xiangtan University, Xiangtan, Hunan 411105, China
通讯机构：
[Zhou, Yong] Xiangtan Univ, Dept Math, Xiangtan 411105, Hunan, Peoples R China.
关键词：
Fractional neutral differential equations;Infinite delay;Existence;Uniqueness
摘要：
In this paper, the Cauchy initial value problem is discussed for the fractional neutral functional differential equations with infinite delay and various criteria on existence and uniqueness are obtained. ©2009 Elsevier Ltd. All rights reserved.
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英文
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Investigating the structural evolution of thiolate protected gold clusters from first-principles
WOS被引频次：141
ESI高被引 SCI-E EI
作者：
Pei, Yong;Zeng, Xiao Cheng
期刊：
Nanoscale ,2012年4(14):4054-4072 ISSN：2040-3364
通讯作者：
Pei, Y.(ypnku78@gmail.com)
作者机构：
[Pei, Yong] Xiangtan Univ, Dept Chem, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Hunan, Peoples R China.;[Zeng, Xiao Cheng] Univ Nebraska, Dept Chem, Lincoln, NE 68588 USA.;[Zeng, Xiao Cheng] Univ Nebraska, Nebraska Ctr Mat Nanosci, Lincoln, NE 68588 USA.
通讯机构：
[Pei, Yong] Xiangtan Univ, Dept Chem, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Hunan, Peoples R China.
关键词：
Atomic packing - Bulk materials - Gold clusters - Gold nanocluster - Grand Challenge - In-depth understanding - Lowest energy structure - Metal cluster - Metal nanoclusters - Nano-sized - Physicochemical property - Recent progress - Special class - Structural evolution - Structural formula - Thiolates
摘要：
Unlike bulk materials, the physicochemical properties of nano-sized metal clusters can be strongly dependent on their atomic structure and size. Over the past two decades, major progress has been made in both the synthesis and characterization of a special class of ligated metal nanoclusters, namely, the thiolate-protected gold clusters with size less than 2 nm. Nevertheless, the determination of the precise atomic structure of thiolate-protected gold clusters is still a grand challenge to both experimentalists and theorists. The lack of atomic structures for many thiolate-protected gold clusters has hampered our in-depth understanding of their physicochemical properties and size-dependent structural evolution. Recent breakthroughs in the determination of the atomic structure of two clusters, [Au<inf>25</inf>(SCH<inf>2</inf>CH <inf>2</inf>Ph)<inf>18</inf>]<sup>q</sup> (q = -1, 0) and Au<inf>102</inf>(p- MBA)<inf>44</inf>, from X-ray crystallography have uncovered many new characteristics regarding the gold-sulfur bonding as well as the atomic packing structure in gold thiolate nanoclusters. Knowledge obtained from the atomic structures of both thiolate-protected gold clusters allows researchers to examine a more general "inherent structure rule" underlying this special class of ligated gold nanoclusters. That is, a highly stable thiolate-protected gold cluster can be viewed as a combination of a highly symmetric Au core and several protecting gold-thiolate "staple motifs", as illustrated by a general structural formula [Au] <inf>a+a′</inf>[Au(SR)<inf>2</inf>]<inf>b</inf>[Au<inf>2</inf>(SR) <inf>3</inf>]<inf>c</inf>[Au<inf>3</inf>(SR)<inf>4</inf>]<inf>d</inf>[Au <inf>4</inf>(SR)<inf>5</inf>]<inf>e</inf> where a, a′, b, c, d and e are integers that satisfy certain constraints. In this review article, we highlight recent progress in the theoretical exploration and prediction of the atomic structures of various thiolate-protected gold clusters based on the "divide-and-protect" concept in general and the "inherent structure rule" in particular. As two demonstration examples, we show that the theoretically predicted lowest-energy structures of Au<inf>25</inf>(SR) <inf>8</inf><sup>-</sup> and Au<inf>38</inf>(SR)<inf>24</inf> (-R is the alkylthiolate group) have been fully confirmed by later experiments, lending credence to the "inherent structure rule". This journal is ©2012 The Royal Society of Chemistry.
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英文
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Iodine-Catalyzed Regioselective Sulfenylation of Indoles with Sodium Sulfinates
WOS被引频次：131
ESI高被引 SCI-E
作者：
Xiao, Fuhong;Xie, Hao;Liu, Saiwen;Deng, Guo-Jun
期刊：
ADVANCED SYNTHESIS & CATALYSIS ,2014年356(2-3):364-368 ISSN：1615-4150
通讯作者：
Deng, GJ
作者机构：
[Liu, Saiwen; Xie, Hao; Deng, Guo-Jun; Xiao, Fuhong] Xiangtan Univ, Coll Chem, Minist Educ, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Peoples R China.;[Deng, Guo-Jun] Chinese Acad Sci, Inst Chem, Key Lab Mol Recognit & Funct, Beijing 100080, Peoples R China.
通讯机构：
[Deng, Guo-Jun] Xiangtan Univ, Coll Chem, Minist Educ, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Peoples R China.
关键词：
indoles;iodine;sodium sulfinates;sulfenylation;transition metal-free conditions
摘要：
An iodine-catalyzed sulfenylation of free indoles with sodium sulfinates is described. The reaction selectively afforded 3-arylthioindoles in good to high yields in anisole under metal-free conditions. Functional groups such as halogens were well tolerated under the optimized reaction conditions.
语种：
英文
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Iodine-catalyzed regioselective 2-sulfonylation of indoles with sodium sulfinates.
WOS被引频次：123
ESI高被引 SCI-E Medline
作者：
Xiao, Fuhong;Chen, Hui;Xie, Hao;Chen, Shuqing;Yang, Luo;Deng, Guo-Jun
期刊：
ORGANIC LETTERS ,2014年16(1):50-53 ISSN：1523-7060
通讯作者：
Deng, GJ
作者机构：
[Chen, Hui; Xie, Hao; Chen, Shuqing; Deng, Guo-Jun; Yang, Luo; Xiao, Fuhong] Xiangtan Univ, Coll Chem, Minist Educ, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Peoples R China.;[Deng, Guo-Jun] Chinese Acad Sci, Inst Chem, Key Lab Mol Recognit & Funct, Beijing 100080, Peoples R China.
通讯机构：
[Deng, Guo-Jun] Xiangtan Univ, Coll Chem, Minist Educ, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Peoples R China.
摘要：
Iodine-catalyzed selective 2-arylsulfonyl indole formation from indoles and sodium sulfinates is disclosed. Various substituted 2-arylsulfonyl indoles were obtained in one pot in the absence of metal catalyst at room temperature under air.
语种：
英文
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On the new concept of solutions and existence results for impulsive fractional evolution equations
WOS被引频次：122
ESI高被引 SCI-E
作者：
Wang, JinRong;Feckan, Michal;Zhou, Yong
（ 周勇 ）
期刊：
DYNAMICS OF PARTIAL DIFFERENTIAL EQUATIONS ,2011年8(4):345-361 ISSN：1548-159X
通讯作者：
Wang, JR
作者机构：
[Zhou, Yong] Xiangtan Univ, Dept Math, Xiangtan 411105, Hunan, Peoples R China.;[Wang, JinRong] Guizhou Univ, Dept Math, Guiyang 550025, Guizhou, Peoples R China.;[Feckan, Michal] Comenius Univ, Dept Math Anal & Numer Math, Fac Math Phys & Informat, Bratislava, Slovakia.
通讯机构：
[Wang, JinRong] Guizhou Univ, Dept Math, Guiyang 550025, Guizhou, Peoples R China.
关键词：
Impulsive conditions;Caputo fractional derivative;Evolution equations;Cauchy problems;Nonlocal problmes;PC-mild solutions
摘要：
In this paper we discuss the existence of PC-mild solutions for Cauchy problems and nonlocal problems for impulsive fractional evolution equations involving Caputo fractional derivative. By utilizing the theory of operators semigroup, probability density functions via impulsive conditions, a new concept on a PC-mild solution for our problem is introduced. Our main techniques based on fractional calculus and fixed point theorems. Some concrete applications to partial differential equations are considered.
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英文
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