Few-layer phosphorene: An emerging electrode material for electrochemical energy storage
作者：
Tao, Yaping;Huang, Ting;Ding, Chunxia* ;Yu, Feng;Tan, Deming;...
期刊：
Applied Materials Today ,2019年15:18-33 ISSN：2352-9407
通讯作者：
Ding, Chunxia;Xie, Qingji
作者机构：
[Tao, Yaping] Luoyang Normal Univ, Key Lab Electromagnet Transformat & Detect Henan, Coll Phys & Elect Informat, Luoyang 471022, Peoples R China.;[Ding, Chunxia] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Xie, Qingji; Huang, Ting; Yao, Shouzhuo] Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ China, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.;[Yu, Feng] Queensland Univ Technol, Sci & Engn Fac, Sch Chem Phys & Mech Engn, Brisbane, Qld 4001, Australia.;[Tan, Deming; Wan, Faxing] Tech Univ Dresden, Dept Chem & Food Chem, D-01062 Dresden, Germany.
通讯机构：
[Ding, Chunxia; Xie, Qingji] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ China, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.
关键词：
Electrode material;Few-layer phosphorene;High-performance;Rechargeable battery;Supercapacitor
摘要：
The emergence of phosphorene in 2014 augments the family of two-dimensional (2D) materials, which soon triggered tremendous interest in the field of physics, chemistry, biomedicine, and materials science. Considering the tunable band gap, large interlayer spacing (0.53 nm), high charge carrier mobility and strong in-plane anisotropy, tremendous research efforts have been dedicated to the exploration of phosphorene's applications in electrochemical energy storage systems. This review, both theoretically and experimentally, introduces the state-of-the-art development of few-layer phosphorene as the electrode material for electrochemical energy storage systems. The discussed electrochemical energy storage systems involve Li-ion batteries, Na-ion batteries, K-ion batteries, Li-S batteries and supercapacitors. More importantly, perspectives on future possibilities and opportunities of electrochemical energy storage devices based on few-layer phosphorene are also suggested, including dual-ion batteries and metal-ion hybrid capacitors. Finally, the key challenges of phosphorene electrodes are provided for the further research in this thriving field. © 2018 Elsevier Ltd
语种：
英文
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Identifying the origin and contribution of pseudocapacitive sodium ion storage in tungsten disulphide nanosheets for application in sodium-ion capacitors
作者：
Ding, Chunxia* ;Huang, Ting;Tao, Yaping;Tan, Deming;Zhang, Yin;...
期刊：
Journal of Materials Chemistry A ,2018年6(42):21010-21017 ISSN：2050-7488
通讯作者：
Ding, Chunxia;Xie, Qingji
作者机构：
[Ding, Chunxia] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Tao, Yaping] Luoyang Normal Univ, Coll Phys & Elect Informat, Luoyang 471022, Peoples R China.;[Xie, Qingji; Huang, Ting] Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ China, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.;[Zhang, Yin; Yu, Feng] Queensland Univ Technol, Fac Sci & Engn, Sch Chem Phys & Mech Engn, Brisbane, Qld, Australia.;[Tan, Deming; Wang, Faxing] Tech Univ Dresden, Dept Chem & Food Chem, D-01062 Dresden, Germany.
通讯机构：
[Ding, Chunxia; Xie, Qingji] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ China, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.
摘要：
Sodium (Na)-ion capacitors are emerging as one of the most promising hybrid devices for next generation electrochemical energy storage systems because of their abundant resources, and environmentally friendly nature as well as the potential integration of Na-ion batteries with high energy density and electrochemical capacitors with high power density. However, the practical application of Na-ion capacitors is severely hampered by the sluggish redox kinetics in anodes. To overcome this obstacle, the most effective approach is to develop a pseudocapacitive anode material for Na ion storage. Here, we demonstrate a predominant pseudocapacitive contribution for Na ion storage in tungsten disulphide (WS2) nanosheets within the potential window of 1-3 V vs. Na/Na+. Particularly, the root cause of pseudocapacitive Na ion storage in WS2 nanosheets was systematically investigated by operando X-ray diffraction (XRD), ex situ synchronous radiation tests and density functional theory (DFT) simulations. This work may provide a fundamental insight into the development of pseudocapacitive materials for electrochemical energy storage systems. © The Royal Society of Chemistry.
语种：
英文
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A DFA-based bivariate regression model for estimating the dependence of PM2.5 among neighbouring cities
作者：
Wang, Fang* ;Wang, Lin;Chen, Yuming
期刊：
Scientific Reports ,2018年8(1):7475 ISSN：2045-2322
通讯作者：
Wang, Fang
作者机构：
[Wang, Fang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Wang, Lin; Wang, Fang] Univ New Brunswick, Dept Math & Stat, Fredericton, NB E3B 5A3, Canada.;[Chen, Yuming] Wilfrid Laurier Univ, Dept Math, Waterloo, ON N2L 3C5, Canada.
通讯机构：
[Wang, Fang] H;[Wang, Fang] U;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Univ New Brunswick, Dept Math & Stat, Fredericton, NB E3B 5A3, Canada.
摘要：
On the basis of detrended fluctuation analysis (DFA), we propose a new bivariate linear regression model. This new model provides estimators of multi-scale regression coefficients to measure the dependence between variables and corresponding variables of interest with multi-scales. Numerical tests are performed to illustrate that the proposed DFA-bsaed regression estimators are capable of accurately depicting the dependence between the variables of interest and can be used to identify different dependence at different time scales. We apply this model to analyze the PM2.5 series of three adjacent cities (Beijing, Tianjin, and Baoding) in Northern China. The estimated regression coefficients confirmed the dependence of PM2.5 among the three cities and illustrated that each city has different influence on the others at different seasons and at different time scales. Two statistics based on the scale-dependent t-statistic and the partial detrended cross-correlation coefficient are used to demonstrate the significance of the dependence. Three new scale-dependent evaluation indices show that the new DFA-based bivariate regression model can provide rich information on studied variables.
语种：
英文
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CT系统模型新模板设计的发现
作者：
陈宣霖;罗涛;何慧玲;王访
期刊：
计算机科学与应用 ,2018年(4):496-502
作者机构：
湖南农业大学理学院;湖南农业大学农业数学建模与数据处理中心
关键词：
多边形模板;卷积;R-L滤波;约登指数
摘要：
计算机断层扫描(Computed Tomography, CT)技术被广泛地应用于医学、工程领域。模板的形状对CT系统参数标定至关重要,本文针对普通的单椭圆和小圆模板进行了改进,设计了三种新的模板。首先利用Radon变换和R-L滤波获取其接收信息,然后基于卷积反投影重建算法得到其重建图,并利用敏感度、特异度和约登指数对重建效果进行了定量评估。与原模板相比,新模板重建效果更好。此外,为了考察其抗噪性,对原模板和新模板分别加入不同强度的高斯噪声,试验结果表明新模板比原模板具有更好的抗噪性。一个有趣的发现是以多边形轮廓的单参考系几何图形比边缘为弧线的多参考系几何图形为模板对CT重建效果更好。
语种：
中文
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基于局部去趋势波动分析的油菜光谱红边位置确定方法
作者：
高菲蕊;沈陆明;王访;廖桂平
期刊：
江苏农业科学 ,2018年46(20):239-243 ISSN：1002-1302
作者机构：
湖南农业大学理学院/农业数学建模与数据处理研究中心,湖南长沙,410128;湖南农业大学理学院/农业数学建模与数据处理研究中心,湖南长沙410128;南方粮油作物协同创新中心,湖南长沙410128;[王访; 廖桂平; 高菲蕊; 沈陆明] 湖南农业大学
关键词：
油菜;红边位置;局部去趋势波动分析
摘要：
对油菜的冠层光谱进行研究,利用局部去趋势波动分析提出了一种红边位置的提取方法,并与最大一阶导数光谱法、倒高斯拟合法、线性四点插值法、拉格朗日插值法、多项式拟合法、线性外推法等6种常见的红边位置确定方法作对比。以油菜角果期冠层光谱红边位置所对应的多重分形指标Hurst指数和另外6种方法提取的红边位置所对应的光谱值为特征,用支持向量机和随机森林2种分类器建立定性识别模型,识别直播和移栽2种种植方式、1万株/667m2和2万株/667m22种密度。以平均识别率为评价指标,结果表明,利用局部去趋势波动分析的提取方法具有较好的识别率和稳定性。
语种：
中文
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油菜相邻生长期光谱动力特征的去趋势波动分析
作者：
卜美婷;邹锐标;王访
期刊：
江苏农业科学 ,2018年46(15):190-194 ISSN：1002-1302
作者机构：
湖南农业大学理学院 /农业数学建模与数据处理研究中心,湖南长沙,410128;湖南农业大学理学院 /农业数学建模与数据处理研究中心,湖南长沙 410128;南方粮油作物协同创新中心,湖南长沙 410128;[邹锐标; 王访; 卜美婷] 湖南农业大学
关键词：
油菜;相邻生长期;光谱动力特征;去趋势波动分析;蓝边;黄边;红边
摘要：
为研究油菜相邻物候期冠层光谱的波动差异性,利用去趋势波动分析（DFA）对4种不同种植方式下的油菜苗期、蕾薹期、开花期和角果发育成熟期4个物候期的冠层光谱进行研究,提出了一种基于DFA的波动差异函数,该函数能有效刻画不同波长光谱的波动差异。结果表明,苗期和蕾薹期在蓝边、黄边和红边范围的波动差异都是显著的;而黄边和红边范围内的光谱只有蕾薹期和开花期的波动差异是显著的。
语种：
中文
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Aqueous Dual-Ion Battery Based on a Hematite Anode with Exposed {104} Facets
作者：
Tao, Yaping;Ding, Chunxia* ;Tan, Deming;Yu, Feng;Wang, Faxing
期刊：
ChemSusChem ,2018年11(24):4269-4274 ISSN：1864-5631
通讯作者：
Ding, Chunxia
作者机构：
[Tao, Yaping] Luoyang Normal Univ, Coll Phys & Elect Informat, Luoyang 471022, Peoples R China.;[Ding, Chunxia] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Yu, Feng] Queensland Univ Technol, Sci & Engn Fac, Sch Chem Phys & Mech Engn, Brisbane, Qld, Australia.;[Tan, Deming; Wang, Faxing] Tech Univ Dresden, Dept Chem & Food Chem, D-01062 Dresden, Germany.
通讯机构：
[Ding, Chunxia] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
anode;aqueous batteries;electrolytes;hematite;high-energy facets
摘要：
<jats:title>Abstract</jats:title><jats:p>The aqueous rechargeable lithium battery (ARLB) is one of the most promising devices for large‐scale grid applications. Currently, a key issue for ARLBs is to develop promising anode materials with favorable electrochemical performances. Here, for the first time, we demonstrate an aqueous battery that utilizes the reversible redox reaction with hydroxide ions (OH<jats:sup>−</jats:sup>) in the hematite (Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub>) anode and a commercial Li ion intercalation compound in neutral solution as the cathode. The fabricated aqueous battery displays a reversible capacity of 92 mAh g<jats:sup><jats:sc>−</jats:sc>1</jats:sup>. The morphology of the used Fe<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> anode with exposed {1 0 4} facets for this aqueous battery is unique and attractive. Importantly, with the dual‐pH neutral–alkaline hybrid electrolyte, many excellent anode materials that previously could only work in alkaline electrolytes can now be successfully combined with commercial cathodes in neutral solutions, which may significantly enrich the range of anode materials for ARLBs. In addition, the reported battery configuration can be extended to other aqueous batteries beyond Li‐ion ones with lower cost.</jats:p>
语种：
英文
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Asymmetric multiscale multifractal detrended cross-correlation analysis for the 1999–2000 California electricity market
作者：
Wang, Fang;Fan, Qingju* ;Wang, Kehao
期刊：
Nonlinear Dynamics ,2018年91(3):1527-1540 ISSN：0924-090X
通讯作者：
Fan, Qingju
作者机构：
[Wang, Fang] Hunan Agr Univ, Agr Math Modeling & Data Proc Ctr, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Fan, Qingju] Wuhan Univ Technol, Sch Sci, Dept Stat, Wuhan, Hubei, Peoples R China.;[Wang, Kehao] Wuhan Univ Technol, Sch Informat Engn, Wuhan, Hubei, Peoples R China.
通讯机构：
[Fan, Qingju] W;Wuhan Univ Technol, Sch Sci, Dept Stat, Wuhan, Hubei, Peoples R China.
关键词：
Multiscale multifractal detrended cross-correlation analysis;Asymmetric cross-correlation;Local Hurst surface
摘要：
In order to access the asymmetric cross-correlation between two time series in a wide range of scales, the method of asymmetric multiscale multifractal detrended cross-correlation analysis (A-MMFCCA) is proposed in this study, which is an extension of the asymmetric detrended fluctuation analysis and the multifractal cross-correlation analysis. Multiscale multifractal detrended cross-correlation analysis enables us to find that the price and the load series of California electricity market exhibit long-range persistent multifractal cross-correlation at different scale ranges during 1999–2000, and the scale range has an important impact on the fractal properties of cross-correlation. Furthermore, the asymmetric cross-correlation between the price and the load series is detected by means of our proposed A-MMFCCA method. Through comparing the local Hurst surfaces with the uptrends and downtrends, we further find that the asymmetric cross-correlation between the price and the load series in 2000 is more significant than that in 1999; the contribution of asymmetric cross-correlation in 1999–2000 mainly depends on different directional trends at different scale ranges. The findings help to interpret the power crisis phenomenon and develop effective and prospective market policy recommendations. © 2017, Springer Science+Business Media B.V., part of Springer Nature.
语种：
英文
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美国州内与州际能源消耗评价模型
作者：
陈宣霖;朱可馨;罗涛;王访
期刊：
低碳经济 ,2018年07(3):109-119 ISSN：2324-7924
作者机构：
[陈宣霖; 朱可馨; 罗涛; 王访] 湖南农业大学理学院，湖南 长沙;湖南农业大学农业数学建模与数据处理中心，湖南 长沙
关键词：
能源结构;能源协定;关联度评价;优劣解距离法
摘要：
摘要: 基于美国能源信息署官网数据，本文首先从静态和动态的角度分析了1960年至2009年加利福尼亚州，亚利桑那州，德克萨斯州和新墨西哥州四个行业的能源消耗情况，结果显示四个州的能源消费结构趋势基本相似。然后，利用关联度评估方法与TOPSIS综合评价法提出一种基于各州指标特征的州内评估模型，用来衡量各州从1960年到2009年的能源使用情况。最后，提出了一个州际评估模型，以适应州际联盟的发展趋势。模型检验显示，四个州有必要签订能源协定进行州际联盟。
语种：
中文
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Local detrended fluctuation analysis for spectral red-edge parameters extraction
作者：
Jiang, Shan;Wang, Fang* ;Shen, Luming* ;Liao, Guiping
期刊：
Nonlinear Dynamics ,2018年93(3):995-1008 ISSN：0924-090X
通讯作者：
Wang, Fang;Shen, Luming
作者机构：
[Shen, Luming; Liao, Guiping; Wang, F; Shen, LM; Jiang, Shan; Wang, Fang] Hunan Agr Univ, Agr Math Modeling & Data Proc Ctr, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liao, Guiping; Wang, Fang] Southern Reg Collaborat Innovat Ctr Grain & Oil C, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Wang, F; Shen, LM] H;Hunan Agr Univ, Agr Math Modeling & Data Proc Ctr, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Local detrended fluctuation analysis;Local Hurst exponent;Rapeseed (Brassica napus);Spectrum;Red-edge parameters
摘要：
Nowadays, spectrum technology makes it possible to nondestructively monitor crop and provide real-time diagnostic advice. Spectral red-edge parameters are important detection target for the growth of rapeseed. In this work, we propose a new method to acquire the rapeseed’s spectral red-edge parameters based on local detrended fluctuation analysis (L-DFA). In practice, by using the L-DFA, local Hurst exponent of the spectrum is calculated firstly. And then, six traditional red-edge parameter extraction methods, namely maximum first derivative method, adjusted linear extrapolation method, linear four-point interpolation method, inverted Gaussian method, Lagrangian interpolation method, and polynomial fitting interpolation, are employed to act on the estimated local Hurst exponent, and thus four red-edge parameters, i.e., red-edge position, red-edge amplitude, and left and right red-edge area, are obtained. In our experiments, by using the above four local Hurst exponent-based red-edge parameters as argument, a prediction model is developed to forecast the SPAD values (soil and plant analyzer development, often used as a parameter to indicate the chlorophyll content) for the five rapeseed’s growth periods based on random decision forest method. The results show that the local Hurst exponent-based red-edge feature can produce better model effect than the original spectrum-based one for the all phenological periods. Significance test for the four kinds of plant patterns shows that there is huge difference of the proposed four-dimensional red-edge features between the transplant and direct plant in the whole process of rapeseed’s growth. The differences between the other three groups of plant factors (two planting densities, two fertilizer types, and two weed controls) are not significant in certain specific growth periods of rapeseed. These findings provide a basis for studying difference of rapeseed yield and oil differences between different planting patterns. © 2018, Springer Science+Business Media B.V., part of Springer Nature.
语种：
英文
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Lagged multi-affine height correlation analysis for exploring lagged correlations in complex systems
作者：
Wang, Fang* ;Wang, Lin;Chen, Yuming
期刊：
CHAOS ,2018年28(6):061102 ISSN：1054-1500
通讯作者：
Wang, Fang
作者机构：
[Wang, Fang] Hunan Agr Univ, Coll Sci, Agr Math Modeling & Data Proc Ctr, Changsha 410128, Hunan, Peoples R China.;[Wang, Lin] Univ New Brunswick, Dept Math & Stat, Fredericton, NB E3B 5A3, Canada.;[Chen, Yuming] Wilfrid Laurier Univ, Dept Math, Waterloo, ON N2L 3C5, Canada.
通讯机构：
[Wang, Fang] H;Hunan Agr Univ, Coll Sci, Agr Math Modeling & Data Proc Ctr, Changsha 410128, Hunan, Peoples R China.
摘要：
In order to analyze lagged correlations hidden in complex systems, we propose a new method by incorporating a time-lagged operator into the multi-affine height correlation analysis (MA-HCA). Application of this lagged MA-HCA to an artificially simulated example indicates that the method is feasible to successfully detect the existence of lagged correlations. We then apply this method to explore lagged correlations in series arising from three real-world complex systems.
语种：
英文
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Extracting sensitive spectrum bands of rapeseed using multiscale multifractal detrended fluctuation analysis
作者：
Jiang, Shan;Wang, Fang* ;Shen, Luming* ;Liao, Guiping;Wang, Lin
期刊：
Journal of Applied Physics ,2017年121(10):104702 ISSN：0021-8979
通讯作者：
Wang, Fang;Shen, Luming
作者机构：
[Shen, Luming; Liao, Guiping; Wang, F; Shen, LM; Jiang, Shan; Wang, Fang] Hunan Agr Univ, Coll Sci, Changsha 410128, Peoples R China.;[Liao, Guiping; Wang, Fang] Southern Reg Collaborat Innovat Ctr Grain & Oil C, Changsha 410128, Hunan, Peoples R China.;[Shen, Luming; Wang, F; Shen, LM; Wang, Fang] Hunan Agr Univ, Agr Math Modeling & Data Proc Ctr, Changsha 410128, Peoples R China.;[Wang, Lin; Wang, Fang] Univ New Brunswick, Dept Math & Stat, Fredericton, NB E3B 5A3, Canada.
通讯机构：
[Wang, F; Shen, LM] H;[Wang, Fang] S;[Wang, Fang] U;Hunan Agr Univ, Coll Sci, Changsha 410128, Peoples R China.;Southern Reg Collaborat Innovat Ctr Grain & Oil C, Changsha 410128, Hunan, Peoples R China.
关键词：
Crops;Forecasting;Fractals;Mean square error;Nearest neighbor search;Nondestructive examination;Oilseeds;Spectrum analysis;Weed control;Correlation coefficient;Evaluation indicators;Information acquisitions;K-nearest neighbor method;Multifractal detrended fluctuation analysis;Multifractal parameters;Non destructive testing;Root mean square errors;Seed
摘要：
Spectrum technology has been widely used in crop non-destructive testing diagnosis for crop information acquisition. Since spectrum covers a wide range of bands, it is of critical importance to extract the sensitive bands. In this paper, we propose a methodology to extract the sensitive spectrum bands of rapeseed using multiscale multifractal detrended fluctuation analysis. Our obtained sensitive bands are relatively robust in the range of 534 nm-574 nm. Further, by using the multifractal parameter (Hurst exponent) of the extracted sensitive bands, we propose a prediction model to forecast the Soil and plant analyzer development values ((SPAD), often used as a parameter to indicate the chlorophyll content) and an identification model to distinguish the different planting patterns. Three vegetation indices (VIs) based on previous work are used for comparison. Three evaluation indicators, namely, the root mean square error, the correlation coefficient, and the relative error employed in the SPAD values prediction model all demonstrate that our Hurst exponent has the best performance. Four rapeseed compound planting factors, namely, seeding method, planting density, fertilizer type, and weed control method are considered in the identification model. The Youden indices calculated by the random decision forest method and the K-nearest neighbor method show that our Hurst exponent is superior to other three Vis, and their combination for the factor of seeding method. In addition, there is no significant difference among the five features for other three planting factors. This interesting finding suggests that the transplanting and the direct seeding would make a big difference in the growth of rapeseed. © 2017 Author(s).
语种：
英文
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农业院校“互联网＋”背景下大学数学教学模式探讨
作者：
王访
期刊：
中国校外教育 ,2017年(8):66-67 ISSN：1004-8502
作者机构：
湖南农业大学理学院;[王访] 湖南农业大学
关键词：
农业院校;“互联网+”;大学数学
摘要：
构建传统大学数学课堂教学的"老师启发、案例教学、师生互动"教学模式与网络教学的"实时学习、网络互动、自由探讨"教学模式融合的体系是高校数学课堂教学的发展模式,本文首先分析了我校大学数学教学改革中存在的问题,之后提出了基于"互联网+"背景下大学数学网络教学模式的新内涵和实际操作规范.
语种：
中文
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基于偏相关与逐步回归方法的AQI影响因素分析及预测
作者：
戴孟莲;王彤;邓海银;王访*
期刊：
环境保护前沿 ,2017年07(3):191-201 ISSN：2164-5485
通讯作者：
王访
作者机构：
[戴孟莲; 王彤; 邓海银; 王访] 湖南农业大学理学院，湖南 长沙;湖南农业大学，农业数学建模与数据处理研究中心，湖南 长沙
通讯机构：
[王访] ;湖南农业大学理学院，湖南 长沙
关键词：
空气质量指数;偏相关分析;逐步回归分析
摘要：
摘要: 空气质量指数(AQI)是定量描述空气质量状况的无量纲指数，可用于评价大气环境质量以及控制污染。本文以北京、长沙、海口AQI及PM2.5等6种大气污染指标的日均数据为研究对象。一方面，分别对三个城市的各个指标进行偏相关分析，结果表明影响北京空气质量的主要因素是PM10、PM2.5、NO2和O3；影响长沙空气质量的主要指标是PM10、PM2.5、NO2和CO；而影响海口空气质量的主要因素是PM10、PM2.5和SO2。北京、长沙对AQI影响最大的是PM2.5，而海口的PM10与AQI的相关关系最为显著。另一方面，应用逐步回归分析得到了影响上述三城市AQI的最显著的空气污染指标，结果与偏相关分析的结果相吻合。此外，通过偏相关分析和逐步回归分析，获得AQI的最优线性回归预测模型，模型的拟合效果显著。模型检验表明建立的预测方程能有效用于AQI的短期预测。最后针对分析结果提出一些解决对策，为空气质量改善提供建议。
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中文
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A quasi-solid-state Li-ion capacitor with high energy density based on Li3VO4/carbon nanofibers and electrochemically-exfoliated graphene sheets
作者：
Wang, Faxing;Liu, Zaichun;Yuan, Xinhai;Mo, Jun;Li, Chunyang;...
期刊：
Journal of Materials Chemistry A ,2017年5(28):14922-14929 ISSN：2050-7488
通讯作者：
Zhu, Yusong;Wu, Yuping;Wu, Xiongwei
作者机构：
[Liu, Zaichun; Yuan, Xinhai; Wang, Faxing; Zhu, Yusong; Zhu, YS; Wu, Yuping; Li, Chunyang; Fu, Lijun] Nanjing Tech Univ, Inst Electrochem Energy Storage, Sch Energy Sci & Engn, Nanjing 211816, Jiangsu, Peoples R China.;[Liu, Zaichun; Wu, Xiongwei; Wang, Faxing; Mo, Jun; Wu, XW; Wu, Yuping] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Wu, Yuping] Fudan Univ, Dept Chem, New Energy & Mat Lab, Shanghai 200433, Peoples R China.;[Wang, Faxing] Tech Univ Dresden, Dept Chem & Food Chem, D-01062 Dresden, Germany.
通讯机构：
[Zhu, YS; Wu, YP] N;[Wu, XW; Wu, YP] H;[Wu, Yuping] F;Nanjing Tech Univ, Inst Electrochem Energy Storage, Sch Energy Sci & Engn, Nanjing 211816, Jiangsu, Peoples R China.;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
摘要：
Electrochemical capacitors are playing increasing roles in our daily life but their low energy densities limit their wide applications. The appearance of Li-ion capacitors (LICs) is regarded as the beginning of a new era of increased energy densities in the field of electrochemical capacitors. However, it is a great challenge to find a suitable anode material with superior electrochemical performance. In addition, the intrinsic instability of the liquid electrolytes used in LICs can easily result in leakage of the electrolyte and causes a serious safety issue. Here, a quasi-solid-state LIC is fabricated by applying Li<inf>3</inf>VO<inf>4</inf>/carbon nanofibers as the anode and electrochemically-exfoliated graphene sheets as the cathode in a gel polymer electrolyte. It achieves an energy density of 110 W h kg<sup>-1</sup>and a good cycling performance. Our results demonstrate that quasi-solid-state LICs provide a key system acting as a bridge between conventional Li-ion batteries and supercapacitors, while meeting the high safety demands of electronic devices. ©2017 The Royal Society of Chemistry.
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英文
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基于ROC图的油菜生长期光谱敏感波段的研究
作者：
段少新;姜珊;王访;邹锐标;廖桂平
期刊：
湖南农业大学学报(自然科学版) ,2017年43(6):684-688 ISSN：1007-1032
作者机构：
湖南农业大学理学院/农业数学建模与数据处理研究中心, 湖南, 长沙, 410128;湖南农业大学理学院/农业数学建模与数据处理研究中心, 南方粮油作物协同创新中心, 湖南, 长沙, 410128;[段少新; 姜珊; 邹锐标] 湖南农业大学理学院/农业数学建模与数据处理研究中心, 湖南, 长沙, 410128;[王访; 廖桂平] 湖南农业大学理学院/农业数学建模与数据处理研究中心, 南方粮油作物协同创新中心, 湖南, 长沙, 410128
关键词：
油菜;生长期;敏感波段;受试者工作特征图
摘要：
测定了直播和移栽油菜的苗期、抽薹期、花期、盛花期和角果期的冠层光谱,构建了比值光谱植被指数(RSI)和归一化光谱植被指数(NDSI)。为了获得区分直播和移栽的最佳RSI和NDSI,利用降采样法和精细采样法相结合的受试者工作特征(ROC)图寻找油菜生长期光谱的敏感波长,直播和移栽油菜各时期RSI和NDSI的最敏感波长分别为:苗期(458 nm,511 nm)和(433 nm,517 nm);抽薹期(997 nm,501 nm)和(990 nm,510 nm);花期(1 235 nm,1 180 nm)和(1 235 nm,1 180 nm);盛花期(478 nm,396 nm)和(484 nm,416 nm);角果期(1 073 nm, 1 037 nm)和(1 092 nm,1 024 nm)。用敏感波长下的2种植被指数为特征,以最近邻法为分类器的定性识别模型,结果花期的区分效果最好,最大约登指数分别为0.941 7和0.945 0。
语种：
中文
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Detecting PM2.5's Correlations between Neighboring Cities Using a Time-Lagged Cross-Correlation Coefficient
作者：
Wang, Fang* ;Wang, Lin;Chen, Yuming
期刊：
Scientific Reports ,2017年7(1):10109 ISSN：2045-2322
通讯作者：
Wang, Fang
作者机构：
[Wang, Fang] Hunan Agr Univ, Coll Sci, Agr Math Modeling & Data Proc Ctr, Changsha, Hunan, Peoples R China.;[Wang, Lin; Wang, Fang] Univ New Brunswick, Dept Math & Stat, Fredericton, NB E3B 5A3, Canada.;[Chen, Yuming] Wilfrid Laurier Univ, Dept Math, Waterloo, ON N2L 3C5, Canada.
通讯机构：
[Wang, Fang] H;[Wang, Fang] U;Hunan Agr Univ, Coll Sci, Agr Math Modeling & Data Proc Ctr, Changsha, Hunan, Peoples R China.;Univ New Brunswick, Dept Math & Stat, Fredericton, NB E3B 5A3, Canada.
摘要：
<jats:title>Abstract</jats:title><jats:p>In order to investigate the time-dependent cross-correlations of fine particulate (PM2.5) series among neighboring cities in Northern China, in this paper, we propose a new cross-correlation coefficient, the time-lagged <jats:italic>q-L</jats:italic> dependent height crosscorrelation coefficient (denoted by <jats:italic>p</jats:italic><jats:sub>
<jats:italic>q</jats:italic>
</jats:sub>(<jats:italic>τ</jats:italic>, <jats:italic>L</jats:italic>)), which incorporates the time-lag factor and the fluctuation amplitude information into the analogous height cross-correlation analysis coefficient. Numerical tests are performed to illustrate that the newly proposed coefficient <jats:italic>ρ</jats:italic><jats:sub>
<jats:italic>q</jats:italic>
</jats:sub>(<jats:italic>τ</jats:italic>, <jats:italic>L</jats:italic>) can be used to detect cross-correlations between two series with time lags and to identify different range of fluctuations at which two series possess cross-correlations. Applying the new coefficient to analyze the time-dependent cross-correlations of PM2.5 series between Beijing and the three neighboring cities of Tianjin, Zhangjiakou, and Baoding, we find that time lags between the PM2.5 series with larger fluctuations are longer than those between PM2.5 series withsmaller fluctuations. Our analysis also shows that cross-correlations between the PM2.5 series of two neighboring cities are significant and the time lags between two PM2.5 series of neighboring cities are significantly non-zero. These findings providenew scientific support on the view that air pollution in neighboring cities can affect one another not simultaneously but with a time lag.</jats:p>
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英文
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A high-capacity dual core-shell structured MWCNTs@S@PPy nanocomposite anode for advanced aqueous rechargeable lithium batteries
作者：
Wu, Xiongwei;Yuan, Xinhai;Yu, Jingang;Liu, Jun;Wang, Faxing;...
期刊：
Nanoscale ,2017年9(31):11004-11011 ISSN：2040-3364
通讯作者：
Zhou, Qingming;Wu, Yuping;Zhu, Yusong
作者机构：
[Zhou, Qingming; Yuan, Xinhai; Wu, Xiongwei; Zhou, QM; Wu, Yuping; Zhou, Wenxin; Liu, Jun] Hunan Agr Univ, Coll Agron, Natl Res Ctr Engn Technol Utilizat Funct Ingredie, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Yuan, Xinhai; Wu, Xiongwei; Wang, Faxing; Zhu, Yusong; Zhu, YS; Wu, Yuping; Fu, Lijun] Nanjing Tech Univ, Coll Energy, Nanjing 211816, Jiangsu, Peoples R China.;[Yuan, Xinhai; Wu, Xiongwei; Wang, Faxing; Zhu, Yusong; Zhu, YS; Wu, Yuping; Fu, Lijun] Nanjing Tech Univ, Inst Electrochem Energy Storage, Nanjing 211816, Jiangsu, Peoples R China.;[Yuan, Xinhai; Wu, Yuping] Fudan Univ, Dept Chem, Shanghai 200433, Peoples R China.;[Yu, Jingang] Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Zhou, QM; Wu, YP] H;[Zhu, YS; Wu, YP] N;[Wu, Yuping] F;Hunan Agr Univ, Coll Agron, Natl Res Ctr Engn Technol Utilizat Funct Ingredie, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Nanjing Tech Univ, Coll Energy, Nanjing 211816, Jiangsu, Peoples R China.
关键词：
Anodes;Binary alloys;Electric batteries;Electric discharges;Electrodes;Electrolytes;Lithium alloys;Nanocomposites;Secondary batteries;Shells (structures);Yarn;Anode material;Aqueous electrolyte;Aqueous rechargeable lithium batteries;Aqueous rechargeable lithium batteries (ARLBs);Electrochemical performance;Initial discharge capacities;Rate capabilities;Sulfur contents;Lithium batteries
摘要：
Anode materials with high capacity for aqueous rechargeable lithium batteries (ARLBs) are very rarely reported. Here we found that a dual core-shell structured MWCNTs@S@PPy nanocomposite prepared by us shows excellent electrochemical performance. Its initial discharge capacity in a saturated LiAc aqueous electrolyte is very high, which is up to 481 mA h g-1 based on the weight of the composite and 879 mA h g-1 based on the sulfur content. It shows excellent rate capability. When nanotube LiMn2O4 is used as a cathode, the assembled ARLB can deliver an energy density of 110 Wh kg-1 based on two electrodes and show excellent cycling. These results show great promise for the practical application of ARLBs. © The Royal Society of Chemistry 2017.
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英文
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油菜大田环境下的WSN 信道传播损耗特性建模研究
作者：
李建辉;王访
期刊：
计算机应用研究 ,2017年34(4):1189-1194 ISSN：1001-3695
作者机构：
广东东软学院计算机科学与技术系, 广东, 佛山, 528225;湖南农业大学理学院, 长沙, 410128;[李建辉] 广东东软学院计算机科学与技术系, 广东, 佛山, 528225;[王访] 湖南农业大学理学院, 长沙, 410128
关键词：
无线传感器网络;信道特性建模;油菜;现场感知
摘要：
针对因特定农业环境下无线信道模型缺乏而造成的现场感知业务的优化与分析难题,建立了油菜大田环境下WSN 信道传播损耗特征模型。以油菜及其生长大田为例,依据不同的生育期提炼出三个典型的测试场景,采用两种载波频率的无线传感器节点测试大田现场的信号损耗值,对测定结果进行了最小二乘法拟合建模,结果表明,供试大田环境下的WSN 信道传播损耗特性与传统的移动信道模型存在较大差异,适合采用多斜率对数阴影衰落经验模型进行表征。以节点的有效传播距离和路径损耗预测值为指标,与free-space、COST321和 Egli 等经典模型比较,对拟合模型进行有效性验证的结果表明,本模型各项指标与实测数据接近,可为优化和设计较高能量效率的现场感知业务系统提供精准参考。
语种：
中文
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LATEST ADVANCES IN SUPERCAPACITORS: FROM NEW ELECTRODE MATERIALS TO NOVEL DEVICE DESIGNS
作者：
Wang, Faxing;Wu, Xiongwei;Yuan, Xinhai;Liu, Zaichun;Zhang, Yi;...
期刊：
CHEMICAL SOCIETY REVIEWS ,2017年46(22):6816-6854 ISSN：0306-0012
通讯作者：
Fu, Lijun;Wu, Yuping;Zhou, Qingming
作者机构：
[Fu, Lijun; Wu, Yuping; Yuan, Xinhai; Liu, Zaichun; Wu, Xiongwei; Wang, Faxing; Huang, Wei; Zhu, Yusong; Zhang, Yi] Nanjing Tech Univ, Sch Energy Sci & Engn, Nanjing 211816, Jiangsu, Peoples R China.;[Fu, Lijun; Wu, Yuping; Yuan, Xinhai; Liu, Zaichun; Wu, Xiongwei; Wang, Faxing; Huang, Wei; Zhu, Yusong; Zhang, Yi] Nanjing Tech Univ, Inst Adv Mat, Nanjing 211816, Jiangsu, Peoples R China.;[Wang, Faxing; Wu, Yuping] Fudan Univ, Dept Chem, Shanghai 200433, Peoples R China.;[Wang, Faxing; Wu, Yuping] Fudan Univ, Shanghai Key Lab Mol Catalysis & Innovat Mat, Shanghai 200433, Peoples R China.;[Wang, Faxing] Tech Univ Dresden, Dept Chem & Food Chem, D-01062 Dresden, Germany.
通讯机构：
[Fu, LJ; Wu, YP] N;[Wu, Yuping] F;[Zhou, Qingming] H;Nanjing Tech Univ, Sch Energy Sci & Engn, Nanjing 211816, Jiangsu, Peoples R China.;Nanjing Tech Univ, Inst Adv Mat, Nanjing 211816, Jiangsu, Peoples R China.
摘要：
Notably, many significant breakthroughs for a new generation of supercapacitors have been reported in recent years, related to theoretical understanding, material synthesis and device designs. Herein, we summarize the state-of-the-art progress toward mechanisms, new materials, and novel device designs for supercapacitors. Firstly, fundamental understanding of the mechanism is mainly focused on the relationship between the structural properties of electrode materials and their electrochemical performances based on some in situ characterization techniques and simulations. Secondly, some emerging electrode materials are discussed, including metal–organic frameworks (MOFs), covalent organic frameworks (COFs), MXenes, metal nitrides, black phosphorus, LaMnO3, and RbAg4I5/graphite. Thirdly, the device innovations for the next generation of supercapacitors are provided successively, mainly emphasizing flow supercapacitors, alternating current (AC) line-filtering supercapacitors, redox electrolyte enhanced supercapacitors, metal ion hybrid supercapacitors, micro-supercapacitors (fiber, plane and three-dimensional) and multifunctional supercapacitors including electrochromic supercapacitors, self-healing supercapacitors, piezoelectric supercapacitors, shape-memory supercapacitors, thermal self-protective supercapacitors, thermal self-charging supercapacitors, and photo self-charging supercapacitors. Finally, the future developments and key technical challenges are highlighted regarding further research in this thriving field.
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英文
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