High-performance and moisture-resistant red-emitting Cs 2 SiF 6 :Mn 4+ for high-brightness LED backlighting
作者：
Liu, Yong;Zhou, Zhi* ;Huang, Lin;Brik, Mikhail G.;Si, Shuaichen;...
期刊：
Journal of Materials Chemistry C ,2019年7(8):2401-2407 ISSN：2050-7526
通讯作者：
Wang, Jing;Zhou, Zhi;Qiu, Jianbei
作者机构：
[Lin, Litian; Si, Shuaichen; Xuan, Tongtong; Liu, Yong; Huang, Lin; Wang, Jing; Liang, Hongbin] Sun Yat Sen Univ, Key Lab Bioinorgan & Synthet Chem, State Key Lab Optoelect Mat & Technol, Sch Chem,Minist Educ, Guangzhou 510275, Guangdong, Peoples R China.;[Zhou, Zhi] Hunan Agr Univ, Coll Sci, Hunan Opt Agr Engn Technol Res Ctr, Changsha 410128, Hunan, Peoples R China.;[Brik, Mikhail G.] Chongqing Univ Posts & Telecommun, Coll Sci, Chongqing 400065, Peoples R China.;[Brik, Mikhail G.] Univ Tartu, Inst Phys, W Ostwald Str 1, EE-50411 Tartu, Estonia.;[Brik, Mikhail G.] Jan Dtugosz Univ, Inst Phys, Armii Krajowej 13-15, PL-42200 Czestochowa, Poland.
通讯机构：
[Wang, Jing] S;[Zhou, Zhi] H;[Qiu, Jianbei] K;Sun Yat Sen Univ, Key Lab Bioinorgan & Synthet Chem, State Key Lab Optoelect Mat & Technol, Sch Chem,Minist Educ, Guangzhou 510275, Guangdong, Peoples R China.;Hunan Agr Univ, Coll Sci, Hunan Opt Agr Engn Technol Res Ctr, Changsha 410128, Hunan, Peoples R China.
关键词：
Color;Fluorine compounds;Light emission;Luminance;Moisture;Phosphors;Precipitation (chemical);Coprecipitation method;Emission intensity;External quantum efficiency;High brightness LEDs;High luminous efficacy;Moisture resistance;Moisture stability;Red emitting phosphor;Light emitting diodes
摘要：
Narrow-band red-emitting fluoride phosphors for wide color gamut LED backlights have evoked considerable attention, due to their fascinating optical properties. Unfortunately, poor moisture resistance often restricts their further applications in optoelectronics. Herein we developed a Cs 2 SiF 6 :Mn 4+ red phosphor using a lowerature co-precipitation method and passivating it by using H 2 O 2 . The phosphor shows a very high external quantum efficiency (EQE) of ∼85% and exhibits excellent moisture stability retaining 74% of its emission intensity after being exposed to high temperature (85 °C) and high humidity (85%) (HTHH) for 168 h. Finally, the high brightness white LED devices combined with the passivated Cs 2 SiF 6 :Mn 4+ exhibit high luminous efficacy of 133 lm W -1 and wide color gamut (∼84.7% NTSC). The results demonstrate that the passivated Cs 2 SiF 6 :Mn 4+ with high EQE and excellent moisture-resistance is promising as a narrow-band red emitting phosphor for wide color gamut LED backlights. © 2019 The Royal Society of Chemistry.
语种：
英文
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Plasma milling modified Sb2S3-graphite nanocomposite as a highly reversible alloying-conversion anode material for lithium storage
作者：
Liu, Yuxuan;Lu, Zhongchen* ;Cui, Jie;Liu, Hui;Liu, Jun;...
期刊：
Electrochimica Acta ,2019年310:26-37 ISSN：0013-4686
通讯作者：
Hu, Renzong;Lu, Zhongchen
作者机构：
[Hu, Renzong; Zhu, Min; Liu, Yuxuan; Liu, Jun] South China Univ Technol, Sch Mat Sci & Engn, Guangdong Prov Key Lab Adv Energy Storage Mat, Guangzhou 510640, Peoples R China.;[Lu, Zhongchen] South China Univ Technol, Sch Mech & Automot Engn, Guangdong Prov Key Lab Adv Energy Storage Mat, Guangzhou 510640, Peoples R China.;[Cui, Jie] South China Univ Technol, Anal & Test Ctr, Guangzhou 510640, Peoples R China.;[Liu, Hui] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Hu, Renzong; Lu, Zhongchen] S;South China Univ Technol, Sch Mat Sci & Engn, Guangdong Prov Key Lab Adv Energy Storage Mat, Guangzhou 510640, Peoples R China.;South China Univ Technol, Sch Mech & Automot Engn, Guangdong Prov Key Lab Adv Energy Storage Mat, Guangzhou 510640, Peoples R China.
关键词：
Antimony sulfide;Plasma milling;Conversion reactions;Reversibility
摘要：
Poor reversibility of conversion and alloying reactions for Sb2S3 limits its application as high capacity anode for rechargeable lithium storage. Herein a facile high-efficiency plasma assisted milling (P-milling) was used to create Sb2S3-C hybrid nanostructure with disk-like Sb2S3 nanograins wrapped within ultrathin graphite nanosheets. Benefiting from the high structure stability and excellent Li+ ion diffusion kinetics in the graphite wrapped Sb2S3 nanostructure, highly reversible conversion and alloying reactions are maintained throughout the long-term cycles. The Sb2S3-C nanocomposite anode demonstrates a high stable capacity of 638.2 mA h g(-1) after 250 cycles at 200 mA g(-1) between 0.01 and 3.0 V vs. Li/Li+, with a high initial Coulombic efficiency of 78.3%. A reversible capacity of 496.1 mA h g(-1) is obtained after 500 cycles even at higher current rate of 1 A g(-1), much superior to those of the unmilled Sb2S3-C and P-milled Sb2S3 anodes. These demonstrate that P-milling could be a promising strategy to create high performance metal chalcogenide anode materials involved both conversion and alloying reactions toward lithium storage. (C) 2019 Elsevier Ltd. All rights reserved.
语种：
英文
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一种基于中文关键字符串核函数的分类算法
作者：
沈黎;肖勇;刘莺
期刊：
吉首大学学报(自然科学版) ,2019年40(1):18-20 ISSN：1007-2985
作者机构：
湖南农业大学理学院,湖南长沙,410128;[沈黎; 肖勇; 刘莺] 湖南农业大学
关键词：
中文关键字符串核函数;农业文本;文本分类
摘要：
提出了一种基于中文关键字符串核函数的分类算法,并在农业文本上进行了分类性能测试.实验结果表明,与传统的中文分类算法相比,基于中文关键字符串核函数的分类算法准确率更高.
语种：
中文
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Two-grid methods for semi-linear elliptic interface problems by immersed finite element methods
作者：
Wang, Yang;Chen, Yanping* ;Huang, Yunqing;Liu, Ying
期刊：
应用数学和力学：英文版 ,2019年40(11):1657-1676 ISSN：0253-4827
通讯作者：
Chen, Yanping
作者机构：
[Wang, Yang; Liu, Ying; Huang, Yunqing] Xiangtan Univ, Sch Math & Computat Sci, Xiangtan 411105, Hunan, Peoples R China.;[Chen, Yanping] South China Normal Univ, Sch Math Sci, Guangzhou 510631, Guangdong, Peoples R China.;[Liu, Ying] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Chen, Yanping] S;South China Normal Univ, Sch Math Sci, Guangzhou 510631, Guangdong, Peoples R China.
关键词：
two-grid method;interface problem;finite element method;immersed interface
摘要：
In this paper, two-grid immersed finite element (IFE) algorithms are proposed and analyzed for semi-linear interface problems with discontinuous diffusion coefficients in two dimension. Because of the advantages of finite element (FE) formulation and the simple structure of Cartesian grids, the IFE discretization is used in this paper. Two-grid schemes are formulated to linearize the FE equations. It is theoretically and numerically illustrated that the coarse space can be selected as coarse as H = O(h1/4) (or H = O(h1/8)), and the asymptotically optimal approximation can be achieved as the nonlinear schemes. As a result, we can settle a great majority of nonlinear equations as easy as linearized problems. In order to estimate the present two-grid algorithms, we derive the optimal error estimates of the IFE solution in the Lp norm. Numerical experiments are given to verify the theorems and indicate that the present two-grid algorithms can greatly improve the computing efficiency. © 2019, Shanghai University and Springer-Verlag GmbH Germany, part of Springer Nature.
语种：
英文
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基于信令平台的手机游戏用户精准营销研究
作者：
刘莺;胡剑炜
期刊：
经济研究导刊 ,2018年(2):119-122 ISSN：1673-291X
作者机构：
湖南农业大学理学院;湘潭大学数学与计算科学学院;[胡剑炜] 中国移动通信集团湖南有限公司;[刘莺] 湖南农业大学
关键词：
信令平台数据;手机游戏;移动运营商;精准营销
摘要：
针对手机游戏用户,移动运营商基于信令平台的网络数据,结合经营分析系统的业务数据,可快速发现手机游戏用户群体的特征,从而建立游戏用户信息模型,精确用户群体标签属性。利用手机游戏用户群的不同特征属性标签,给用户模拟画像,精准定位营销活动目标用户,结合市场部活动,制定差异化的精准营销策略,可以提升用户体验,降低对非目标客户的打扰,提升用户满意度;同时,可以引导用户消费,促进移动运营商业务的发展。
语种：
中文
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Effect of pyrolysis condition on the adsorption mechanism of lead, cadmium and copper on tobacco stem biochar
作者：
Zhou, Zhi;Xu, Zhihui;Feng, Qiuju;Yao, Denghui;Yu, Jingang;...
期刊：
Journal of Cleaner Production ,2018年187:996-1005 ISSN：0959-6526
通讯作者：
Zhou, Nan;Zhong, Mei-e
作者机构：
[Zhou, Nan; Zhong, ME; Zhong, Mei-e; Zhou, Zhi; Xu, Zhihui; Yao, Denghui] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Feng, Qiuju] Jishou Univ, Coll Chem & Chem Engn, Jishou 416000, Peoples R China.;[Yu, Jingang] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Liu, Yifei; Wang, Desheng; Lv, Shuangqing] Tarim Univ, Coll Plant Sci, Alar Xinjiang 843300, Peoples R China.
通讯机构：
[Zhou, N; Zhong, ME] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Adsorbents;Adsorption;Cadmium compounds;Copper compounds;Crystal structure;Decontamination;Heavy metals;Lead compounds;Positive ions;Tobacco;Adsorption mechanism;Bio chars;Cation-pi interactions;Environmental pollutions;High-temperature pyrolysis;Oxygen functional groups;Surface functional groups;Tobacco stems;Pyrolysis
摘要：
To promote the application of biochar in environmental pollution decontamination especially the heavy metals amendment, the relationship between the adsorption mechanism and biochar pyrolysis conditions was investigated. Tobacco stem was pyrolyzed at 300–700 °C for various residence time of 2 h, 4 h and 6 h. The adsorption of lead, cadmium and copper in single solute was then analyzed for as-obtained biochars. The change of the crystal structures, the related functional groups, and the exchanged cations were determined to reveal the effect of pyrolysis conditions on the adsorption mechanisms of these three heavy metals. The change of crystal structure confirmed that precipitation was the main mechanism of lead adsorption and that the tobacco stem biochar obtained at 700 °C for around 2 h was excellent adsorbent for lead clearance, since high temperature pyrolysis could promote the formation of carbonates but they would be decomposed under long-time exposure. The alteration of surface functional groups and exchanged cations of both original and demineralized biochars followed an affinity order of Cu(II)>Cd(II)>Pb(II) to oxygen functional groups. The surface complexation should be the primary mechanism of copper adsorption. Thus, the tobacco stem biochars pyrolyzed at 400 °C for 4 h could be effective adsorbents for copper amendment. Despite of the important role of precipitation in its removal, cadmium favores the cation-π interaction best, and the biochars derived from tobacco stem at 700 °C for the residence time of 4–6 h are good adsorbents for cadmium decontamination. © 2018 Elsevier Ltd
语种：
英文
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Simply and sensitively simultaneous detection hepatocellular carcinoma markers AFP and miRNA-122 by a label-free resonance light scattering sensor
作者：
Chen, Feng;Zhang, Feng;Liu, Yi;Cai, Changqun*
期刊：
Talanta ,2018年186:473-480 ISSN：0039-9140
通讯作者：
Cai, Changqun
作者机构：
[Cai, Changqun; Liu, Yi; Chen, Feng] Xiangtan Univ, Coll Chem, Key Lab Green Organ Synth & Applicat Hunan Prov, Key Lab Environm Friendly Chem & Applicat,Minist, Xiangtan 411105, Peoples R China.;[Zhang, Feng] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Cai, Changqun] X;Xiangtan Univ, Coll Chem, Key Lab Green Organ Synth & Applicat Hunan Prov, Key Lab Environm Friendly Chem & Applicat,Minist, Xiangtan 411105, Peoples R China.
关键词：
AFP;Bifunctional;Label-free;Simultaneous detection;miRNA
摘要：
In this study, an intelligent and label-free sensor is utilized for the first time to one-spot simultaneous detection hepatocellular carcinoma markers AFP and miRNA-122 by a resonance light scattering (RLS) sensor. cDNA1 hybridizes with cDNA2 to form double-stranded DNA (dsDNA). The construction of dsDNA and methyl violet is used to form the RLS sensor via the electronic interaction. When AFP or miRNA-122 is present, the cDNA (cDNA1 or cDNA2) can bindings of target, thereby RLS intensity changed proportionally with the concentration of AFP or that of miRNA-122. The detection limits of AFP and miRNA-122 are 0.94 μg/L and 98 pM respectively, and their good linear which ranges from 5 to 100 μg/L and 200 pM to 10 nM are achieved using the assay. In the presence of miRNA-122 and AFP mixtures, AFP bound to the AFP aptamer to increase the RLS signal, and miRNA-122 bound to the miRNA-122 complementary strand to decrease the RLS signal. The RLS signal changed in response to changing AFP and miRNA-122 concentrations, so that one-spot simultaneous detection of alpha fetal protein and miRNA-122 is achieved. This method has potential practical applications in the research of hepatocellular carcinoma.<br/> ©2018 Elsevier B.V.
语种：
英文
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基于大数据的高铁通信网络质量分析及优化
作者：
刘莺;胡剑炜
期刊：
信息技术 ,2018年(6):17-21 ISSN：1009-2552
作者机构：
湖南农业大学理学院信科系;湘潭大学数学与计算科学学院智能计算与信息处理教育部重点实验室;[胡剑炜] 中国移动通信集团湖南有限公司;[刘莺] 湖南农业大学
关键词：
高铁通信网络;大数据分析;网络优化
摘要：
通过大数据的采集及分析将用户、小区、路线、方向、时间、场景六维度汇聚成一整体,基于高铁用户身份识别、用户定位、乘车方向识别等,实现高铁用户脱网/公网用户入侵高风险区域的判断,对异常事件进行定位分析,并构造基于多维度算法的高铁专网质量评估体系,实现全方面的精准监控与质量分析,以提升高铁用户业务感知。
语种：
中文
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A Review of Epidemic Models Related to Meteorological Factors
作者：
Liu, Yuewu;Peng, Yan* ;Li, Qingfan;Xiong, Xiangquan
期刊：
CURRENT BIOINFORMATICS ,2018年13(4):360-366 ISSN：1574-8936
通讯作者：
Peng, Yan
作者机构：
[Li, Qingfan; Liu, Yuewu; Xiong, Xiangquan] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Yuewu] Agr Math Modeling & Data Proc Ctr, Changsha 410128, Hunan, Peoples R China.;[Peng, Yan] Hunan Agr Univ, Sci & Technol Innovat Platform, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Peng, Yan] H;Hunan Agr Univ, Sci & Technol Innovat Platform, Changsha 410128, Hunan, Peoples R China.
关键词：
Infectious disease;weather factor;meteorological factor;deterministic models;stochastic models.
摘要：
Background: An epidemic can spread rapidly among a large number of people in a community within a short period of time. Some infectious diseases, including influenza, hand, foot and mouth disease, dengue and meningitis, are temporally limited by variations in the meteorological factors, such as sunshine, temperature, humidity, rainfall, atmospheric pressure, wind speed and so on. Therefore, it is necessary to predict the behavior of outbreak of these infectious diseases based on meteorological factors. Objective: Review various epidemic models related to meteorological factors. Results: We discuss two kinds of epidemic models: deterministic models and stochastic models. The deterministic models include switched SIR model, seasonal SIR model, periodic SEIR system and seasonal SEIQR model. And the stochastic models involve multiple regression models, auto-regressive moving average model, autoregressive distributed lag model, time series Poisson regression models and generalized additive models. Furthermore, we introduce the latest applications of these models, respectively. Conclusion: In our work, these deterministic models and stochastic models can successfully predict the diseases outbreak using meteorological factors, and they all are now widely used in the field. However, few meteorological factors are used in these models. With the development of Meteorological Science, large amounts of Meteorological factor data will be obtained. More key Meteorological factors causing an epidemic will be identified. Therefore, in the future, more key meteorological factors will be considered in models and they will further improve the accuracy of the forecast.
语种：
英文
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基于用户感知的移动数据业务端到端优化
作者：
刘莺;胡剑炜
期刊：
吉首大学学报(自然科学版) ,2018年39(1):49-53 ISSN：1007-2985
作者机构：
湖南农业大学理学院信科系;湘潭大学数学与计算科学学院智能计算与信息处理教育部重点实验室;[胡剑炜] 中国移动通信集团湖南有限公司;[刘莺] 湖南农业大学
关键词：
用户感知;移动数据;端到端;质量优化
摘要：
利用LTE信令监测系统的信令数据对XDR数据的完整性、规范性和准确性进行核查,提升XDR数据质量.完善感知问题,如综合业务低速率质差小区、频繁乒乓TAU问题、质差互联网网元的定界方法,提高问题定界和定位的准确性.以高铁通信网络质量分析及优化为例,拓展信令数据在端到端业务感知质量提升中的支撑能力.端到端优化效果的大量数据表明,用户感知质量指标得到持续提升.
语种：
中文
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Mathematical modeling of HIV-like particle assembly in vitro
作者：
Liu, Yuewu;Zou, Xiufen*
期刊：
Mathematical Biosciences ,2017年288:46-51 ISSN：0025-5564
通讯作者：
Zou, Xiufen
作者机构：
[Zou, Xiufen; Liu, Yuewu] Wuhan Univ, Sch Math & Stat, Computat Sci Hubei Key Lab, Wuhan 430072, Peoples R China.;[Liu, Yuewu] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Zou, Xiufen] W;Wuhan Univ, Sch Math & Stat, Computat Sci Hubei Key Lab, Wuhan 430072, Peoples R China.
关键词：
Assembly;Computational geometry;Dynamics;Equilibrium constants;Geometry;Mathematical models;Rate constants;Recombinant proteins;Computational costs;Concentration variation;Existence and uniqueness;Initial concentration;Mathematical analysis;Particle assemblies;Positive equilibrium;Spherical particle;Nonlinear equations;geometry;human immunodeficiency virus;numerical model;protein;chemical binding;disease model;geometry;Human immunodeficiency virus;in vitro study;mathematical analysis;nonhuman;rate constant;statistical model;biological model;chemistry;growth, development and aging;Human immunodeficiency virus 1;virus assembly;Human immunodeficiency virus 1;HIV-1;Models, Biological;Virus Assembly
摘要：
In vitro, the recombinant HIV-1 Gag protein can generate spherical particles with a diameter of 25–30nm in a fully defined system. It has approximately 80 building blocks, and its intermediates for assembly are abundant in geometry. Accordingly, there are a large number of nonlinear equations in the classical model. Therefore, it is difficult to compute values of geometry parameters for intermediates and make the mathematical analysis using the model. In this work, we develop a new model of HIV-like particle assembly in vitro by using six-fold symmetry of HIV-like particle assembly to decrease the number of geometry parameters. This method will greatly reduce computational costs and facilitate the application of the model. Then, we prove the existence and uniqueness of the positive equilibrium solution for this model with 79 nonlinear equations. Based on this model, we derive the interesting result that concentrations of all intermediates at equilibrium are independent of three important parameters, including two microscopic on-rate constants and the size of nucleating structure. Before equilibrium, these three parameters influence the concentration variation rates of all intermediates. We also analyze the relationship between the initial concentration of building blocks and concentrations of all intermediates. Furthermore, the bounds of concentrations of free building blocks and HIV-like particles are estimated. These results will be helpful to guide HIV-like particle assembly experiments and improve our understanding of the assembly dynamics of HIV-like particles in vitro. © 2017 Elsevier Inc.
语种：
英文
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Rapid green synthesis of gold nanocatalyst for high-efficiency degradation of quinclorac
作者：
Shi, Guorong* ;Li, Yulu;Xi, Gaihong;Xu, Qinqin;He, Zijun;...
期刊：
Journal of Hazardous Materials ,2017年335:170-177 ISSN：0304-3894
通讯作者：
Shi, Guorong
作者机构：
[Shi, Guorong; Xu, Qinqin; Cai, Jun; He, Zijun; Li, Yulu] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Yating; Shi, Guorong; Xi, Gaihong] Hunan Agr Univ, Tobacco Res Inst, Changsha 410128, Hunan, Peoples R China.;[Zhang, Jianhui] Hunan Inst Food Qual Supervis Inspect & Res, Changsha 410111, Hunan, Peoples R China.
通讯机构：
[Shi, Guorong] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Catalyst activity;Catalysts;Dechlorination;Efficiency;Gold;Gold nanoparticles;Nanocatalysts;Nanoparticles;Rate constants;Sodium Borohydride;Yeast;Catalytic dechlorination;Gold nanocatalyst;High-efficiency;Organic solvent-free;Particle diameters;Pseudo-first order kinetic model;Quinclorac;Reductive dechlorination;Gold compounds;carboxylic acid derivative;gold nanoparticle;herbicide;mannoprotein;quinclorac;sodium borohydride;unclassified drug;borane derivative;gold;herbicide;metal nanoparticle;quinclorac;quinoline derivative;catalyst;concentration (composition);dechlorination;degradation;gold;nanoparticle;quinclorac;reaction kinetics;temperature effect;yeast;Article;concentration (parameters);controlled study;dechlorination;degradation;fungal cell wall;green chemistry;nanocatalyst;nonhuman;particle size;rate constant;Saccharomyces cerevisiae;synthesis;temperature;transmission electron microscopy;yeast cell;catalysis;chemistry;halogenation;infrared spectroscopy;kinetics;metabolism;ultraviolet spectrophotometry;X ray diffraction;Saccharomyces cerevisiae;Borohydrides;Catalysis;Gold;Green Chemistry Technology;Halogenation;Herbicides;Kinetics;Metal Nanoparticles;Microscopy, Electron, Transmission;Quinolines;Saccharomyces cerevisiae;Spectrophotometry, Ultraviolet;Spectroscopy, Fourier Transform Infrared;Temperature;X-Ray Diffraction
摘要：
Porous chemical pretreated Saccharomyces cerevisiae was used as support, stabilizer, and reducing agent for the rapid green synthesis of gold nanocatalyst. Au nanoparticles (Au NPs) were generated through in-situ reduction of the absorbed Au(III) by the reductive functional groups of mannoproteins in yeast cell wall. The obtained spherical mono-dispersed Au NPs have an average particle diameter of 9.99±1.63nm as evidenced by TEM image, and exhibits excellent catalytic activity for the dechlorination of quinclorac to 8-quinoline-carboxylic acid by sodium borohydride. The reductive dechlorination of quinclorac is chemical reaction controlled and follows pseudo-first-order kinetic model. The rate constant increases with the increase of the temperature and decrease of the initial quinclorac concentration. The present synthesis protocol of Au nanocatalyst has the advantages of rapid, convenient and mild operation, high catalytic dechlorination efficiency and organic solvent-free nature. © 2017 Elsevier B.V.
语种：
英文
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Mathematical modeling and quantitative analysis of HIV-1 Gag trafficking and polymerization
作者：
Liu, Yuewu;Zou, Xiufen*
期刊：
PLOS COMPUTATIONAL BIOLOGY ,2017年13(9):e1005733 ISSN：1553-734X
通讯作者：
Zou, Xiufen
作者机构：
[Zou, Xiufen; Liu, Yuewu] Wuhan Univ, Computat Sci Hubei Key Lab, Sch Math & Stat, Wuhan, Hubei, Peoples R China.;[Liu, Yuewu] Hunan Agr Univ, Coll Sci, Changsha, Hunan, Peoples R China.
通讯机构：
[Zou, Xiufen] W;Wuhan Univ, Computat Sci Hubei Key Lab, Sch Math & Stat, Wuhan, Hubei, Peoples R China.
关键词：
Monomers;Dimers;Polymers;Cytoplasm;Polymerization;HIV-1;Cell membranes;Molecular motors
摘要：
Gag, as the major structural protein of HIV-1, is necessary for the assembly of the HIV-1 sphere shell. An in-depth understanding of its trafficking and polymerization is important for gaining further insights into the mechanisms of HIV-1 replication and the design of antiviral drugs. We developed a mathematical model to simulate two biophysical processes, specifically Gag monomer and dimer transport in the cytoplasm and the polymerization of monomers to form a hexamer underneath the plasma membrane. Using experimental data, an optimization approach was utilized to identify the model parameters, and the identifiability and sensitivity of these parameters were then analyzed. Using our model, we analyzed the weight of the pathways involved in the polymerization reactions and concluded that the predominant pathways for the formation of a hexamer might be the polymerization of two monomers to form a dimer, the polymerization of a dimer and a monomer to form a trimer, and the polymerization of two trimers to form a hexamer. We then deduced that the dimer and trimer intermediates might be crucial in hexamer formation. We also explored four theoretical combined methods for Gag suppression, and hypothesized that the N-terminal glycine residue of the MA domain of Gag might be a promising drug target. This work serves as a guide for future theoretical and experimental efforts aiming to understand HIV-1 Gag trafficking and polymerization, and might help accelerate the efficiency of anti-AIDS drug design. © 2017 Liu, Zou.
语种：
英文
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Chemical treatment and chitosan coating of yeast cells to improve the encapsulation and controlled release of bovine serum albumin
作者：
Shi, Guorong* ;Liu, Yating;He, Zijun;Zhou, Jihen*
期刊：
ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY ,2017年45(6):1207-1215 ISSN：2169-1401
通讯作者：
Shi, Guorong;Zhou, Jihen
作者机构：
[Liu, Yating; Shi, Guorong; He, Zijun] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Yating; Shi, Guorong; Zhou, Jihen] Hunan Agr Univ, Tobacco Res Inst, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Shi, Guorong; Zhou, Jihen] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, Tobacco Res Inst, Changsha 410128, Hunan, Peoples R China.
关键词：
Yeast cells;bovine serum albumin;chemical treatment;chitosan coating;controlled delivery;microcapsule
摘要：
We investigate the encapsulation of bovine serum albumin (BSA) in chemical-treated and chitosan-coated yeast cells, Saccharomyces cerevisiae (S. cerevisiae), for the controlled release of BSA. The chemical treatment can sufficiently enlarge the small-sized cell-wall cavities and/or break the integrity for the entrance of BSA to the interior of yeast cells, and the additional chitosan coating can well prevent the rapid release of encapsulated BSA from the yeast-derived microcapsules. The sodium hydroxide pretreated S. cerevisiae gives a maximum encapsulation yield of (10.1 ± 0.2)% for BSA. An additional coating of S. cerevisiae with chitosan can reduce the initial burst release of BSA and extend the release period from 24 h in the chitosan-free case to 48 h in phosphate buffer at pH 7.4. The prepared microcapsules can well keep the shapes and sizes of yeast cells and thus show uniform sizes of 3.85 ± 0.81 μm. The encapsulated BSA well retains its pristine ultraviolet spectroscopic and chromatographic behaviors. The present microencapsulation protocol has the advantages of convenient and mild operation, high encapsulation efficiency, and organic solvent-free nature, which is of reference value for establishing high-performance controllable biomacromolecule-delivery systems. © 2016 Informa UK Limited, trading as Taylor & Francis Group.
语种：
英文
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Prediction of Lysine Malonylation Sites Based on Pseudo Amino Acid
作者：
Xiang, Qilin;Feng, Kaiyan;Liao, Bo;Liu, Yuewu;Huang, Guohua*
期刊：
COMBINATORIAL CHEMISTRY & HIGH THROUGHPUT SCREENING ,2017年20(7):622-628 ISSN：1386-2073
通讯作者：
Huang, Guohua
作者机构：
[Liao, Bo; Huang, Guohua; Xiang, Qilin] Hunan Univ, Coll Comp Sci & Elect Engn, Changsha, Hunan, Peoples R China.;[Huang, Guohua] Shaoyang Univ, Hunan Prov Key Lab Informat Serv Rural Southweste, Shaoyang, Peoples R China.;[Huang, Guohua] Shaoyang Univ, Dept Informat Engn, Shaoyang, Hunan, Peoples R China.;[Feng, Kaiyan] Guangdong AIB Polytech, Dept Comp Sci, Guangzhou, Guangdong, Peoples R China.;[Liu, Yuewu] Hunan Agr Univ, Coll Sci, Changsha, Hunan, Peoples R China.
通讯机构：
[Huang, Guohua] H;Hunan Univ, Coll Comp Sci & Elect Engn, Changsha, Hunan, Peoples R China.
关键词：
Protein post-translational modification;dataset;leave-one-out test;lysine malonylation;pseudo amino acid composition;support vector machine
摘要：
Aim and Objective: Protein malonylation is a newly discovered post-translational modification. Malonylation is known to closely be associated with type 2 diabetes and to play its regulatory role in fatty acid oxidation and the associated genetic disease. Identifying protein malonylations might lay a solid foundation to explore malonylation function. Due to the limitations of experimental techniques, it is a great challenge to fast and accurately identify malonylation sites. Methods: We proposed a computational method to predict malonylation sites and to analyze malonylation pattern. We firstly extracted protein segments so that the lysine is at the center of each segment. Then, each segment was encoded by the pseudo amino acid compositions. The support vector machine classifier trained by a training dataset was built to distinguish malonylation sites from non-malonylation ones. Results: The leave-one-out test on the training dataset reached the accuracy of 0.7733, and the independent test on the testing dataset got 0.8889. Furthermore, the classifier also successfully identified 144 of 160 putative malonylation sites. Analyses on the differences between malonylation and non-malonylation segments implicated that lysine malonylation should follow a specific pattern, e.g. lysine with its neighbors being Glycine and Alanine might be more likely to be malonylated. Therefore, the proposed method is expected to be a promising tool to identify malonylation sites. © 2017 Bentham Science Publishers.
语种：
英文
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Crystal structure and luminescence properties of the blue-green-emitting Ba9(Lu, Y)2Si6O24:Ce3 + phosphor
作者：
Xu, Huawei* ;Zhou, Zhi* ;Liu, Yongfu* ;Liu, Qunxing;He, Zhiyuan;...
期刊：
LUMINESCENCE ,2017年32(5):812-816 ISSN：1522-7235
通讯作者：
Xu, Huawei;Zhou, Zhi;Liu, Yongfu
作者机构：
[Liu, Qunxing; Wang, Shen; Xu, Huawei; He, Zhiyuan; Huang, Linyi] Qual Inspect & Testing Ctr, Res Inst MIIT 5, 110 Dongguan Zhuang Rd, Guangzhou 510610, Guangdong, Peoples R China.;[Zhou, Zhi] Hunan Agr Univ, Coll Sci, 1 Nongda Rd, Changsha 410128, Hunan, Peoples R China.;[Liu, Yongfu] Chinese Acad Sci, NIMTE, 1219 Western Zhongguan Rd, Ningbo 315201, Zhejiang, Peoples R China.;[Zhu, Hongbo] Chinese Acad Sci, Changchun Inst Opt Fine Mech & Phys, 3888 Nanhu Rd, Changchun 130033, Peoples R China.
通讯机构：
[Xu, Huawei] Q;[Zhou, Zhi] H;[Liu, Yongfu] C;Qual Inspect & Testing Ctr, Res Inst MIIT 5, 110 Dongguan Zhuang Rd, Guangzhou 510610, Guangdong, Peoples R China.;Hunan Agr Univ, Coll Sci, 1 Nongda Rd, Changsha 410128, Hunan, Peoples R China.
关键词：
Crystal structure;Light emitting diodes;Luminescence;Phosphors;Solid state reactions;Thermodynamic stability;Blue-green phosphor;Ce 3+;Ce3 + luminescence;Crystals structures;Green phosphor;Luminescence properties;Near ultraviolet;Structure property;Synthesised;White LED's;Silicates;cerium;luminescent agent;lutetium;chemistry;color;crystallization;luminescence;powder;X ray diffraction;Cerium;Color;Crystallization;Luminescent Agents;Luminescent Measurements;Lutetium;Powders;X-Ray Diffraction
摘要：
Samples of the Ba9(Lu2-xYx)Si6O24:Ce3 + (x=0–2) blue-green phosphors were synthesized by solid-state reactions. All the samples exhibited a rhombohedral crystal structure. As the Y3 + concentration increased, the diffraction peaks shifted to the small angle region and the lattice parameters increased due to the larger ionic radius of Y3 + (r=0.900Å) compared with that of Lu3 + (r=0.861Å). Under 400nm excitation, samples exhibited strong blue-green emissions around 490nm. The emission bands had a slight blue shift that resulted from weak crystal-field splitting with increasing Y3 + concentration. Luminescence intensity and quantum efficiency (QE) decreased with increasing Y3 + concentration. The internal QE decreased from 74 to 50% and the external QE decreased from 50 to 34% as x increased from 0 to 2. The thermal stability of the Lu series was better than that of the Y-series. The excitation band peak around 400nm matched well with the emission light from the efficient near-ultraviolet (NUV) chip. These results indicate promising applications for these NUV-based white light-emitting diodes. Copyright © 2017 John Wiley & Sons, Ltd.
语种：
英文
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Quantitative Analysis of Genetic Relationship of Species Based on the Network for Protein-Coding DNA Sequences
作者：
Peng, Yan;Liu, Yuewu* ;Ruan, Sichun;Wei, Yulin
期刊：
MATCH-COMMUNICATIONS IN MATHEMATICAL AND IN COMPUTER CHEMISTRY ,2016年75(2):403-416 ISSN：0340-6253
通讯作者：
Liu, Yuewu
作者机构：
[Peng, Yan] Hunan Agr Univ, Key Lab Crop Germplasm Innovat & Utilizat Hunan P, Changsha 410128, Hunan, Peoples R China.;[Ruan, Sichun; Liu, Yuewu; Wei, Yulin] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Liu, Yuewu] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
摘要：
A novel quantitative analysis method of genetic relationship of species is presented, which is based on the network composed of 20 nodes corresponding to 20 amino acids and edges corresponding to their interactions. The degree of genetic relationship of species is determined by the distance of the vectors which consist of 40 elements corresponding to the out-degrees and in-degrees of 20 nodes. Compared with the classical methods, it avoids choosing the four reference directions corresponding to four bases of DNA sequence, whose optimal angles are very difficult to get. Moreover, our method is efficient because it only computes the distance of vectors. In contrast, much time is spent for the classical methods on computing the eigenvalue of matrix, which has large sizes for long DNA sequence. The contrast experiments show that this approach is superior to the classical methods.
语种：
英文
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An acid-free rechargeable battery based on PbSO4 and spinel LiMn2O4 (vol 50, pg 13714, 2014)
作者：
Liu, Yu;Wen, Zubiao* ;Wu, Xiongwei* ;Wang, Xiaowei;Wu, Yuping* ;...
期刊：
Chemical Communications ,2016年52(48):7620-7620 ISSN：1359-7345
通讯作者：
Wu, Xiongwei;Wu, Yuping;Wen, Zubiao;Holze, Rudolf
作者机构：
[Liu, Yu; Wu, Xiongwei; Wu, XW; 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, NEML, Dept Chem, 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：
[Wu, XW; Wu, YP] H;[Wen, Zubiao] J;[Holze, Rudolf] T;[Wu, Yuping] F;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
摘要：
<p>Correction for ‘An acid-free rechargeable battery based on PbSO<sub>4</sub> and spinel LiMn<sub>2</sub>O<sub>4</sub>’ by Yu Liu <italic>et al.</italic>, <italic>Chem. Commun.</italic>, 2014, <bold>50</bold>, 13714–13717.</p>
语种：
英文
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Origin and Luminescence of Anomalous Red-Emitting Center in Rhombohedral Ba9Lu2Si6O24:Eu2+ Blue Phosphor
作者：
Liu, Yongfu* ;Zhang, Changhua;Cheng, Zhixuan;Zhou, Zhi;Jiang, Jun* ;...
期刊：
INORGANIC CHEMISTRY ,2016年55(17):8628-8635 ISSN：0020-1669
通讯作者：
Liu, Yongfu;Jiang, Jun;Jiang, Haochuan
作者机构：
[Jiang, Haochuan; Zhang, Changhua; Jiang, Jun; Liu, Yongfu; Jiang, HC] Chinese Acad Sci, Ningbo Inst Mat Technol & Engn, Ningbo 315201, Zhejiang, Peoples R China.;[Cheng, Zhixuan; Zhang, Changhua] Shanghai Univ, Dept Chem, Coll Sci, Shanghai 200444, Peoples R China.;[Zhou, Zhi] Hunan Agr Univ, Coll Sci, 1 Nongda Rd, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Liu, YF; Jiang, J; Jiang, HC] C;Chinese Acad Sci, Ningbo Inst Mat Technol & Engn, Ningbo 315201, Zhejiang, Peoples R China.
摘要：
We obtain a blue phosphor, Ba9Lu2Si6O24:Eu2+ (BLS:Eu2+), which shows a strong emission peak at 460 nm and a weak tail from 460 to 750 nm. A 610 nm red emission is observed for the first time in this kind of rhombohedral structure material, which is much different from the same crystal structure of Ba9Sc2Si6O24:Eu2+ and Ba9Y2Si6O24:Eu2+. The luminescence properties and decays from 10 to 550 K are discussed. The new red emission arises from a trapped exciton state of Eu2+ at the Ba site with a larger coordination number (12-fold). It exhibits abnormal luminescence properties with a broad bandwidth and a large Stokes shift. Under the 400 nm excitation, the external quantum efficiency of BLS:Eu2+ is 45.4%, which is higher than the 35.7% for the commercial blue phosphor BAM:Eu2+. If the thermal stability of BLS:Eu2+ can be improved, it will show promising applications in efficient near-UV-based white LEDs.
语种：
英文
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在线开放课程建设的研究与实践——以湖南农业大学“信息论基础”课程为例
作者：
刘莺;周丽;刘凯;胡剑炜
期刊：
河北农业大学学报(农林教育版) ,2016年18(2):106-108 ISSN：1008-6927
作者机构：
湖南农业大学理学院;[胡剑炜] 中国移动通信集团有限公司;[刘凯; 刘莺; 周丽] 湖南农业大学
关键词：
在线开放课程;课程设计;教学模式;“信息论基础”课程
摘要：
随着在线开放课程的兴起,湖南农业大学积极响应教育教学改革的号召,于2013年开始在线开放课程的建设工作,现已取得优异成效。结合"信息论基础"课程的特点,从学习资源的设计、学习活动的设计、课程管理的实施3方面介绍在线开放课程的建设与实施。其中,学习资源的设计包含静态和动态学习资源的设计。在线开放课程使教学模式进行了转变,包括单一任课教师转为教学团队协同教学;创建以"学"为主课堂,实现以人为本的改革;形成翻转课堂和混合式教学。教学实践表明,使用在线开放课程辅助教学不仅给师生提供了交流互动的平台,还能激发学习者的主观能动性,并通过管理模板给予学生及时全面的学习评价和反馈,从而推动考核方式的改革,在线开放课程更能实现优质教育资源的共享。
语种：
中文
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