A Traditional Quadrilateral NURBS Surfaces Generation Method using MATLAB
作者：
Li, Jiang*
期刊：
Procedia Engineering ,2011年24:672-676 ISSN：1877-7058
通讯作者：
Li, Jiang
作者机构：
[Li, Jiang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Li, Jiang] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
会议名称：
IEEE international conference on emergency management and management sciences
会议时间：
2012-08-10
会议地点：
Beijing(CN)
会议主办单位：
Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
会议论文集名称：
Proceedings of 2012 IEEE 3rd international conference on emergency management and management sciences
关键词：
NURBS Surface;Generation Method;MATLAB
摘要：
NURBS surface is defined as a bi-parameter condition, so you can construct a NURBS surface may be calculated surface points the two aspects of some parameters of the algorithm. Build the way surface grid method has higher accuracy than. Also, when the surface of the normal vector calculation pointed out that the surface point can be got. It is to alleviate the surface of the isometric construction. The results show that NURBS surface generation method is effective and strategy, and by adjusting the produce come quadrilateral surface is feasible to control some of the areas.
语种：
英文
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Convergence of iterates with errors of semicontractive mappings
作者：
Miao, Yu* ;Shen, Luming
期刊：
Journal of Global Optimization ,2011年50(2):221-227 ISSN：0925-5001
通讯作者：
Miao, Yu
作者机构：
[Miao, Yu] Henan Normal Univ, Coll Math & Informat Sci, Xinxiang 453007, Henan, Peoples R China.;[Shen, Luming] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Miao, Yu] H;Henan Normal Univ, Coll Math & Informat Sci, Xinxiang 453007, Henan, Peoples R China.
关键词：
Iterative scheme with errors;Hemicontractive mapping;Common fixed points
摘要：
In this paper, we are concerned with the study of an iterative scheme with errors involving two hemicontractive mappings. We approximate the common fixed points of these two mappings by weak and strong convergence of the iteration process in Hilbert space.
语种：
英文
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The inhibitory effects of pure black tea theaflavins on the growth of four selected human cancer cells
作者：
Wang, Kunbo;Liu, Zhonghua* ;Huang, Jianan;Bekhit, Alaa El-Din;Liu, Fang;...
期刊：
Journal of Food Biochemistry ,2011年35(6):1561-1567 ISSN：0145-8884
通讯作者：
Liu, Zhonghua
作者机构：
[Liu, Zhonghua; Wang, Kunbo; Gong, Yushun; Huang, Jianan; Liu, Fang] Hunan Agr Univ, Key Lab Tea Sci, Minist Educ, Changsha 410128, Hunan, Peoples R China.;[Liu, Zhonghua; Wang, Kunbo; Gong, Yushun; Huang, Jianan; Liu, Fang] Hunan Agr Univ, Hunan Prov Key Lab Crop Germplasm Innovat & Utili, Changsha 410128, Hunan, Peoples R China.;[Fu, Donghe; Liu, Zhonghua; Wang, Kunbo] Hunan Agr Univ, Dept Tea Sci, Changsha 410128, Hunan, Peoples R China.;[Dong, Xinrong] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Bekhit, Alaa El-Din] Univ Otago, Dept Food Sci, Dunedin, New Zealand.
通讯机构：
[Liu, Zhonghua] H;Hunan Agr Univ, Key Lab Tea Sci, Minist Educ, Changsha 410128, Hunan, Peoples R China.
摘要：
The growth inhibition and cytotoxic effects of theaflavins mixture and pure theaflavins [theaflavin, theaflavins-3-gallate, theaflavins-3′-gallate and theaflavin-3, 3′-digallate] from black tea on human liver cancer HepG2 cells, gastric cancer SGC-7901 cells, lung cancer A549 cells and acute promyelocytic leukemia K562 cells were investigated. The four major theaflavins were obtained from enzymatically oxidized catechins mixture using preparative high-performance liquid chromatography (HPLC). The purity and the structures of the isolated compounds were confirmed by <sup>1</sup>H nuclear magnetic resonance, Liquid chromatography-mass spectrometry (LC/MS), Fourier-transform infrared, HPLC with diode array detection and thin-layer chromatography analyses. Theaflavin monomers and mixture exhibited strong inhibitory effects on SGC-7901 and A549 cells. The obtained TF2A exhibited high inhibition activity against the growth of all four cancer cells examined. It is concluded that individual theaflavins have differential inhibitory activity in cancer cell lines and that TF2A have promising activity to be considered in anticancer treatment research as a drug or a template for drug synthesis. PRACTICAL APPLICATIONS: Theaflavins have received much attention because of their potential benefits for human health. In this study, we used a modified method for the preparation and isolation of theaflavins and examined the cytotoxic activity of the individual theaflavins against human liver cancer (HepG2) cells, gastric cancer (SGC-7901) cells, lung cancer (A549) cells and acute promyelocytic leukemia (K562) cells. Our results demonstrates that individual theaflavins have differential inhibitory activity in cancer cell lines and has the potential to be used individually for functional food applications and for therapy targeting specific cancer treatments. The most active theaflavin (TF2A) is a promising compound that can be used as a drug or a template for drug synthesis for anticancer research. ©2011 Wiley Periodicals, Inc.
语种：
英文
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Facile synthesis of humic acid-coated iron oxide nanoparticles and their applications in wastewater treatment
作者：
Zhou, Chunjiao;Wu, Zhen;Zhang, Wenjie;Xia, Mingxia;Dai, Guozhang;...
期刊：
Functional Materials Letters ,2011年4(4):373-376 ISSN：1793-6047
通讯作者：
Zou, Bingsuo
作者机构：
[Zhou, Chunjiao] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Zou, Bingsuo; Dai, Guozhang] Beijing Inst Technol, Sch MSE, Micronano Technol Ctr, Beijing 100081, Peoples R China.;[Xia, Mingxia; Zeng, Guangming; Wu, Zhen; Zhang, Wenjie] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.;[Zhang, Panyue] Beijing Forestry Univ, Sch Environm Sci & Engn, Beijing 100083, Peoples R China.
通讯机构：
[Zou, Bingsuo] B;Beijing Inst Technol, Sch MSE, Micronano Technol Ctr, Beijing 100081, Peoples R China.
关键词：
Superparamagnetic;iron oxide;humic acid;adsorption;water treatment
摘要：
Humic acid (HA)-coated Fe3O4 (Fe3O4/HA) superparamagnetic nanoparticles were synthesized by a chemical co-precipitation method with cheap and environmental friendly iron salts and HA. The as-synthesized samples were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR) and vibrating sample magnetometer (VSM). The Fe3O4/HA nanoparticles showed faster adsorption rate and higher removal capacity of cationic organic dye Methylene blue (MB) in neutral water. Moreover, the MB desorption could be easily completed. And the reused performance of Fe3O4/HA nanoparticles was also excellent.
语种：
英文
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Study on reaction kinetics of lipase-catalyzed synthesis of vanillyl nonanoate in acetone media
作者：
Liu, Huilin* ;Liu, Shao;Dong, Xinrong;Xie, Daping
期刊：
Advanced Materials Research ,2011年233-235:2660-2664 ISSN：1022-6680
通讯作者：
Liu, Huilin
作者机构：
[Liu, Huilin; Liu, Shao; Xie, Daping] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha, Hunan, Peoples R China.;[Liu, Shao] Hunan Agr Univ, Coll Food Sci & Technol, Changsha, Peoples R China.;[Dong, Xinrong] Hunan Agr Univ, Coll Sci, Changsha, Peoples R China.
通讯机构：
[Liu, Huilin] H;Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha, Hunan, Peoples R China.
会议名称：
International Conference on Chemical Engineering and Advanced Materials
会议时间：
MAY 28-30, 2011
会议地点：
Changsha, PEOPLES R CHINA
会议主办单位：
[Liu, Huilin;Liu, Shao;Xie, Daping] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha, Hunan, Peoples R China.^[Liu, Shao] Hunan Agr Univ, Coll Food Sci & Technol, Changsha, Peoples R China.^[Dong, Xinrong] Hunan Agr Univ, Coll Sci, Changsha, Peoples R China.
会议论文集名称：
Advanced Materials Research
关键词：
Enzymatic synthesis;Lipase;Ping-pong Bi-Bi reaction;Vanillyl nonanoate
摘要：
The reaction kinetics for synthesis of vanillyl nonanoate (VN) by lipase-catalyzed transesterification of vanillyl alcohol and methyl nonanoate in acetone was investigated in this study. The reaction catalyzed by lipase was carried out as follows: A reaction mixture containing given concentration of substrates (1ml) and lipase Novozyme 435 (20mg) in acetone (1ml) was shaken at 30°C for 10min. The initial velocity of the reaction was calculated according to the concentration of VN detected by high performance liquid chromatography (HPLC), and the kinetic equation was obtained by analysis of the double reciprocal plot of initial velocity versus substrate concentration. The data calculated by the kinetic equation were basically in agreement with the experimental data with a correlation coefficient at 0.997. The inhibitory action of methanol (by-product) in the reaction was also investigated and the results indicated that the concentration of methanol influences both slope and intercept of y-axis of the double reciprocal curve, and the lines intersect on the X-axis. These results revealed that this transesterification follows the Ping-Pong reaction mechanism. ©(2011) Trans Tech Publications, Switzerland.
语种：
英文
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Dynamical simulations of Ptn (1≤n≤7) clusters on Pt(1 1 1) surface
作者：
Tang, Jianfeng;Yang, Jianyu*
期刊：
Physica B: Condensed Matter ,2011年406(13):2543-2547 ISSN：0921-4526
通讯作者：
Yang, Jianyu
作者机构：
[Tang, Jianfeng] Hunan Agr Univ, Dept Appl Phys, Changsha 410128, Hunan, Peoples R China.;[Yang, Jianyu] Hunan Inst Engn, Dept Maths & Phys, Xiangtan 411104, Peoples R China.
通讯机构：
[Yang, Jianyu] H;Hunan Inst Engn, Dept Maths & Phys, Xiangtan 411104, Peoples R China.
关键词：
Cluster;Molecular dynamics;Surface diffusion
摘要：
Field-ion microscopy measurements show a large value of the diffusion prefactor for the Pt<inf>7</inf> cluster, exceeding those of small Pt <inf>n</inf> (n≤4) clusters by two orders of magnitude. In the present paper, with long-time (∼0.2μs) simulations and tracing of interstitial atoms on the surface, a linear relation between the mean square displacement of the cluster's mass-center and the simulation time is obtained. The activation energy and prefactor for two-dimensional atomic clusters Pt<inf>n</inf> (1≤n≤7) on the Pt(1 1 1) surface are determined by molecular dynamics. The present simulations can interpret the experimental data reasonably. The large prefactor of the Pt<inf>7</inf> cluster could be attributed to a large number of nonequivalent diffusion processes with similar activation energies on the soft Pt surface. ©2011 Elsevier B.V. All rights reserved.
语种：
英文
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Global existence of the finite energy weak solutions to a nematic liquid crystals model
作者：
Xu, Jiankai* ;Tan, Zhong
期刊：
Mathematical Methods in the Applied Sciences ,2011年34(8):929-938 ISSN：0170-4214
通讯作者：
Xu, Jiankai
作者机构：
[Xu, Jiankai] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Tan, Zhong] Xiamen Univ, Sch Math Sci, Xiamen 361005, Fujian, Peoples R China.
通讯机构：
[Xu, Jiankai] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
penalized function;weak solution;nematic liquid crystals model
摘要：
In this paper, we are concerned with a simplified hydrodynamic equation, proposed by Ericksen and Leslie, modeling the flow of nematic liquid crystals. For a bounded domain in R(3), under the assumption that initial density belongs to L(gamma)(Omega), gamma>3/2, we show the global existence of weak solutions to the nematic liquid crystals model with a penalized system. Furthermore, we also obtain the energy inequality for weak solutions. Copyright (C) 2011 John Wiley & Sons, Ltd.
语种：
英文
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结合强势卖方期权的电力远期合同模型
作者：
王访;邹锐标
期刊：
电力系统保护与控制 ,2011年39(1):78-82 ISSN：1674-3415
通讯作者：
Wang, F.(topwang619@163.com)
作者机构：
[王访] Orient Science and Technology College, Hunan Agriculture University, Changsha 410128, China;[邹锐标] Science College, Hunan Agriculture University, Changsha 410128, China
通讯机构：
[Wang, F.] O;Orient Science and Technology College, Hunan Agriculture University, China
关键词：
电力市场;大发电商;强势卖方期权;风险管理;最优决策
摘要：
随着电力市场垄断的不断减弱,区域卖方垄断市场的发电商的风险日渐明显。结合期权思想,设计了一种包含强势卖方期权的电力远期合同,以发电商期望收益最大化建模,得到了其在签订合同时应购买的强势卖方期权最优数量的解析解。通过理论研究和算例随机模拟分析,说明了这种包含强势卖方期权的电力远期合同比普通单边差价合同更具实用性,并证明了发电商通过签订该合同能提高期望收益。
语种：
中文
展开
Fast and considerable adsorption of methylene blue dye onto graphene oxide
作者：
Zhang, Wenjie;Zhou, Chunjiao* ;Zhou, Weichang;Lei, Aihua;Zhang, Qinglin;...
期刊：
Bulletin of Environmental Contamination and Toxicology ,2011年87(1):86-90 ISSN：0007-4861
通讯作者：
Zhou, Chunjiao
作者机构：
[Zhang, Qinglin; Wan, Qiang; Lei, Aihua; Zhang, Wenjie; Zhou, Weichang] Hunan Univ, Sch Chem & Chem Engn, Micronano Ctr, Changsha 410082, Hunan, Peoples R China.;[Zhou, Chunjiao] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Zou, Bingsuo] Beijing Inst Technol, Micronano Technol Ctr, Sch MSE, Beijing 100081, Peoples R China.
通讯机构：
[Zhou, Chunjiao] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Adsorption;Methylene blue;Graphene oxide;Electrostatic attraction;Langmuir model
摘要：
The quite efficient adsorption of methylene blue dye from an aqueous solution by graphene oxide was studied. The favorable electrostatic attraction is the main interaction between methylene blue and graphene oxide. As graphene oxide has the special nanostructural properties and negatively charged surface, the positively charged methylene blue molecules can be easily adsorbed on it. In the aqueous solution of methylene blue at 293 K, the adsorption data could be fitted by the Langmuir equation with a maximum adsorption amount of 1.939 mg/mg and a Langmuir adsorption equilibrium constant of 18.486 mL/mg. The adsorption amount increased with the increase of the solution pH (3-11), was not affected significantly by KCl under the examined condition and the adsorption process was exothermic in nature. The fast and considerable adsorption of graphene oxide could be regarded as a potential adsorbent for cationic dye removal in wastewater treatment process. © 2011 Springer Science+Business Media, LLC.
语种：
英文
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Research on Zr50 Al15 Ni10 Cu25 bulk amorphous alloys prepared by mechanical alloying and low pressure sintering
作者：
Long, W. Y.* ;Ouyang, X. Q.;Zuo, C. G.;Zhu, L. G.;Gao, C.;...
期刊：
Powder Metallurgy ,2011年54(3):257-261 ISSN：0032-5899
通讯作者：
Long, W. Y.
作者机构：
[Zhu, L. G.; Long, W. Y.; Gao, C.; Zuo, C. G.; Ouyang, X. Q.; Lu, A. X.] Cent S Univ, Sch Mat Sci & Engn, Changsha 410083, Peoples R China.;[Long, W. Y.] Hunan Agr Univ, Dept Appl Phys, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Long, W. Y.] C;Cent S Univ, Sch Mat Sci & Engn, Changsha 410083, Peoples R China.
关键词：
Mechanical alloying;Amorphous alloys;Activation energy;Low pressure sintering
摘要：
Amorphous Zr<inf>50</inf>Al<inf>15</inf>Ni<inf>10</inf>Cu<inf>25</inf> alloy powders were fabricated by mechanical alloying technique with commercially pure element powders. The effects of small amount of C, Si<inf>3</inf>N <inf>4</inf> and SiC powders addition on the thermal stability and crystallisation behaviour of the Zr<inf>50</inf>Al<inf>15</inf>Ni <inf>10</inf>Cu<inf>25</inf> amorphous alloy were investigated. The blended powders were compacted into bars by oil hydraulic press, and were sintered in argon atmosphere at different temperatures and pressures. The samples before and after sintering were characterised by X-ray diffraction, scanning electron microscopy, differential scanning calorimetry and electron tensile testing machine. The results demonstrated that a proper addition of Si<inf>3</inf>N <inf>4</inf> powders to the amorphous matrix can improve the thermal stability of the matrix. Suitable additives can help to improve the density and mechanical properties of the matrix in sintering process. ©2011 Institute of Materials, Minerals and Mining.
语种：
英文
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Strong stability of the mono-tubular heat exchanger equation with output feedback
作者：
Chen, Jian-Hua* ;Lu, Wen-Ying;Peng, Dao-Lin
期刊：
Systems & Control Letters ,2011年60(1):15-18 ISSN：0167-6911
通讯作者：
Chen, Jian-Hua
作者机构：
[Lu, Wen-Ying; Chen, Jian-Hua] Hunan Univ Sci & Technol, Sch Math & Computat Sci, Xiangtan 411201, Hunan, Peoples R China.;[Peng, Dao-Lin] Hunan Agr Univ, Sch Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Chen, Jian-Hua] H;Hunan Univ Sci & Technol, Sch Math & Computat Sci, Xiangtan 411201, Hunan, Peoples R China.
关键词：
Mono-tubular heat exchanger equation;C(0)-semigroup;Strong stability;Miyadera-Voigt perturbation
摘要：
We investigate asymptotic behavior of the C0-semigroup T(t) associated with the mono-tubular heat exchanger equation with output feedback by a perturbation method. It is shown that T(t) is bounded if a constraint is satisfied by the parameters and the spatial distribution function. Further, applying the Arendt–Batty–Lyubich–Vu theorem, a criterion is established to judge strong stability of T(t).
语种：
英文
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Amorphous mechanism of Zr50 Al15 Ni10 Cu25 amorphous alloy powder prepared by mechanical alloying
作者：
欧阳雪琼;龙卧云;唐武彪;李婧;卢安贤
期刊：
粉末冶金材料科学与工程 ,2010年15(3):225-228 ISSN：1673-0224
通讯作者：
Lu, A.-X.(axlu@mail.csu.edu.cn)
作者机构：
[卢安贤; 欧阳雪琼; 李婧; 唐武彪; 龙卧云] School of Material Science and Engineering, Central South University, Changsha 410083, China;[龙卧云] College of Science, Hunan Agricultural University, Changsha 410128, China
通讯机构：
[Lu, A.-X.] S;School of Material Science and Engineering, Central South University, China
关键词：
Zr50Al15Ni10Cu25粉末;机械合金化;非晶化机制;晶粒极度细化
摘要：
用Zr,Al,Ni和Cu的元素粉末,采用机械合金化的方法在转速为400 r/min、球料质量比20：1的条件下制备具有非晶结构的Zr50Al15 Ni10Cu25粉末,研究其非晶化机制。用X射线衍和扫描电镜分析粉末的结构、晶粒尺寸和形貌。结果表明：在球磨8 h后可使Zr50Al15 Ni10Cu25混合粉末非晶化,晶粒尺寸约80 nm;球磨过程中并没有出现任何过饱和固溶体或者中间合金相,非晶化过程是由于球磨过程中球磨罐和磨球对粉末的不断冲击、剪切、摩擦和挤压,使混合粉末中的晶粒极度细化而直接转变为非晶态颗粒,得到非晶粉末。
语种：
中文
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Global exponential stability of MAM neural network with time delays
作者：
Zhou, Tiejun;Wang, Ming;Fang, Haiquan;Li, Xiaoqun
期刊：
Proceedings 2010 IEEE 5th International Conference on Bio-Inspired Computing: Theories and Applications, BIC-TA 2010 ,2010年:6-10
通讯作者：
Zhou, T.(tj_zhou@hunau.net)
作者机构：
[Zhou, Tiejun; Fang, Haiquan; Wang, Ming] College of Science, Hunan Agricultural University, Changsha, Hunan 410128, China;[Zhou, Tiejun; Li, Xiaoqun] College of Orient Science and Technology, Hunan Agricultural University, Changsha, Hunan 410128, China
摘要：
By extending the bidirectional associative memory neural network model, a mathematical model of multidirectional associative memory(MAM) neural networks with constant time delays is proposed. By using Brouwer fixed point theorem and the upper right Dini derivative, a sufficient condition for the existence and the global exponential stability of an equilibrium point is obtained. And for a special MAM neural network which connection weights is positive, a sufficient and necessary condition for the existence and the global exponential stability of an equilibrium point is obtained. The results are new for MAM neural networks. An example and its numerical simulation are given to illustrate the effectiveness of the obtained results. ©2010 IEEE.
语种：
英文
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Low temperature synthesis of high quality carbon nanospheres through the chemical reactions between calcium carbide and oxalic acid
作者：
Xie, Yonggui* ;Huang, Qizhong;Huang, Baiyun;Xie, Xiangmin
期刊：
Materials Chemistry and Physics ,2010年124(1):482-487 ISSN：0254-0584
通讯作者：
Xie, Yonggui
作者机构：
[Huang, Baiyun; Xie, Yonggui; Huang, Qizhong] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.;[Xie, Xiangmin] Hunan Agr Univ, Dept Appl Chem, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Xie, Yonggui] C;Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
关键词：
Chemical synthesis;Electron microscopy;Nanostructures;Raman spectroscopy
摘要：
Carbon nanospheres (CNSs) were synthesized through the chemical reactions of calcium carbide and oxalic acid without using catalysts. The chemical reactions were carried out in a sealed stainless steel pressure vessel with various molar ratios at temperatures of 65–250 °C. The synthesized CNSs have been characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) attached to the SEM, transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectroscopy. The total yield of carbonaceous materials relative to the starting material is about 4% (w/w). SEM and TEM results reveal that the percentage of CNSs is high (>95%). The CNSs that have been synthesized are roe-like spheres of relatively uniform size with diameters of 60–120 nm. The attached EDS result shows that the carbon content of CNSs reaches up to 98%.
语种：
英文
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Preparation of Biodiesel by Transesterification of Rapeseed Oil with Methanol Using Solid Base Catalyst Calcined K2CO3/gamma-Al2O3
作者：
Liu, Xianghua;Xiong, Xingyao;Liu, Canming* ;Liu, Dengyou;Wu, Anjun;...
期刊：
JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY ,2010年87(7):817-823 ISSN：0003-021X
通讯作者：
Liu, Canming
作者机构：
[Wu, Anjun; Liu, Canming; Liu, Xianghua; Liu, Dengyou] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Chunlin; Liu, Xianghua; Xiong, Xingyao] Key Lab Plant Resource Utilizat Hunan Prov, Changsha 410128, Hunan, Peoples R China.;[Hu, Qiulong] Hunan Agr Univ, Coll Hort & Gardening, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Liu, Canming] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Biodiesel;Methanol;Rapeseed oil;Solid base catalyst;Transesterification
摘要：
We report here the preparation of biodiesel by transesterification of rapeseed oil with methanol using calcined K2CO3/gamma-Al2O3 as a solid base catalyst. The prepared catalysts were characterized using SEM, IR and BET, and their catalytic activities were evaluated. The reaction conditions were optimized, and in particular, the conversion can be as high as 98.62% under the optimal reaction conditions. In addition, the effect of the presence of water in the reaction system on the catalytic activity was also studied.
语种：
英文
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基于色调分形维数的柑橘糖度和有效酸度检测
作者：
曹乐平;温芝元;沈陆明
期刊：
农业机械学报 ,2010年41(3):143-148 ISSN：1000-1298
通讯作者：
Wen, Z.(wenzhiyuan6629@163.com)
作者机构：
[曹乐平] Educational Affairs Department, Hunan Biological and Electromechanical Polytechnic, Changsha 410127, China;[沈陆明; 温芝元] College of Science, Hunan Agricultural University, Changsha 410128, China
通讯机构：
College of Science, Hunan Agricultural University, China
关键词：
柑橘;糖度;有效酸度;机器视觉;无损检测;色调;分形维数
摘要：
研究了宫川温州蜜柑糖度及有效酸度的机器视觉检测技术及影响检测精度的因素.对机器视觉系统采集的柑橘图像进行图像裁切、亮度法去图像背景和RGB空间至HSI空间的转换,将柑橘色调范围分割为0°～20°、20°～40°、40°～60°、60°～80°、80°～100°和100°～120°共6个区域,提取各区域色调分形维数,以此作为BP神经网络输入,无损检测宫川温州蜜柑糖度及有效酸度.167个测试样本的检测结果表明:在±1.5°Brix精度范围内糖度正确识别率为66.6175%,在±0.5精度范围内有效酸度正确识别率为73.9275%.宫川温州蜜柑糖度及有效酸度与果皮色调分形维数之间具有相关性,可用机器视觉检测其糖度及有效酸度.
语种：
中文
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Entanglement dynamics of a double two-photon Jaynes-Cummings model with Kerr-like medium
作者：
Ouyang Xi-Cheng;Fang Mao-Fa* ;Kang Guo-Dong;Deng Xiao-Juan;Huang Li-Yuan
期刊：
中国物理B ,2010年19(3):55-60 ISSN：1674-1056
通讯作者：
Fang Mao-Fa
作者机构：
[Kang Guo-Dong; Ouyang Xi-Cheng; Deng Xiao-Juan; Fang Mao-Fa] Hunan Normal Univ, Coll Phys & Informat Sci, Changsha 410081, Hunan, Peoples R China.;[Ouyang Xi-Cheng] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Huang Li-Yuan] Changsha Univ, Dept Elect & Commun Engn, Changsha 410003, Hunan, Peoples R China.
通讯机构：
[Fang Mao-Fa] H;Hunan Normal Univ, Coll Phys & Informat Sci, Changsha 410081, Hunan, Peoples R China.
关键词：
entanglement sudden death;concurrence;two-photon Jaynes-Cummings model;Kerr-like medium
摘要：
In this paper, the entanglement dynamics of a double two-photon Jaynes-Cummings model with Kerr-like medium is investigated. It is shown that initial entanglement has an interesting subsequent time evolution, including the so-called entanglement sudden death effect. It is also shown analytically that the Kerr-like medium can repress entanglement sudden death and enhance the degree of atom-atom entanglement. A more interesting fact is that the Kerr effect is more obvious when each of the two cavities with have the Kerr-like medium than only one of them with the Kerr-like medium.
语种：
英文
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Surface self-diffusion of a Pt adatom on cuboctahedral and truncated decahedral clusters, size dependence
作者：
Yang, J. Y.* ;Hu, W. Y.;Tang, J. F.
期刊：
EUROPEAN PHYSICAL JOURNAL B ,2010年78(3):315-321 ISSN：1434-6028
通讯作者：
Yang, J. Y.
作者机构：
[Yang, J. Y.] Hunan Inst Engn, Dept Math & Phys, Xiangtan 411104, Peoples R China.;[Hu, W. Y.] Hunan Univ, Dept Appl Phys, Changsha 410082, Hunan, Peoples R China.;[Tang, J. F.] Hunan Agr Univ, Dept Appl Phys, Changsha 410028, Hunan, Peoples R China.
通讯机构：
[Yang, J. Y.] H;Hunan Inst Engn, Dept Math & Phys, Xiangtan 411104, Peoples R China.
关键词：
The European Physical Journal B;Condensed Matter;Complex Systems;journal;EPJ
摘要：
The self-diffusion of single Pt adatom on the surface of cuboctahedral and truncated decahedral clusters with 561-10179 atoms are studied within the context of the many-body potentials obtained via the embedded atom method. The minimum energy diffusion path and the corresponding energy barrier for adatom diffusion on the cuboctahedral and truncated decahedral clusters surfaces are determined through a combination of the quenched molecular dynamics and the nudged elastic band method. The calculated energy barriers are consistent with the available experimental data. The dependence of energy barrier for adatom diffusion across the step edge on the cluster size is found. For the larger cuboctahedral and truncated decahedral clusters, the simulations show that the movement of the adatom is confined to a central region, and the adatom may escape from the center region only at elevated temperatures. In addition, we also find that the truncated decahedral structure is more favorable over the cuboctahedral structure for smaller clusters. The cluster growth experiments support our results. © 2010 EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg.
语种：
英文
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Effect of reactant phase form on the properties of LiFePO4 synthesized by carbothermal reduction method
作者：
Zhong, Mei-e* ;Zhou, Zhentao
期刊：
Solid State Ionics ,2010年181(35-36):1607-1610 ISSN：0167-2738
通讯作者：
Zhong, Mei-e
作者机构：
[Zhong, Mei-e] Hunan Agr Univ, Coll Sci, Changsha 410128, Peoples R China.;[Zhou, Zhentao] S China Univ Technol, Coll Mat Sci & Engn, Guangzhou 510640, Guangdong, Peoples R China.
通讯机构：
[Zhong, Mei-e] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Peoples R China.
关键词：
Carbothermal reduction method;Cathode;LiFePO4;Lithium ion batteries
摘要：
Pure olivine LiFePO<inf>4</inf>/C composite compounds are synthesized by carbothermal reduction (CTR) method using trigonal anhydrous FePO<inf>4</inf> raw material. The physical and electrochemical properties of the prepared samples are investigated in comparison with those of a sample obtained from incompletely crystallized hydrous FePO<inf>4</inf>•2H<inf>2</inf>O. The olivine LiFePO<inf>4</inf>/C prepared with trigonal anhydrous FePO<inf>4</inf> has a high discharge capacity of 142 mAh g<sup>- 1</sup> at 0.1 C. The composite also displays a better rate capability, a higher discharge capacity and a more stable cycle-life than that synthesized with incompletely crystallized hydrous FePO<inf>4</inf>•2H<inf>2</inf>O. The improved electrochemical performance of trigonal anhydrous FePO<inf>4</inf> synthesis samples originates mainly from the single-phase structure and small particle size. ©2010 Elsevier B.V. All rights reserved.
语种：
英文
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LSQR iterative common symmetric solutions to matrix equations AXB = E and CXD = F
作者：
Chen, Yabo;Peng, Zhenyun;Zhou, Tiejun*
期刊：
Applied Mathematics and Computation ,2010年217(1):230-236 ISSN：0096-3003
通讯作者：
Zhou, Tiejun
作者机构：
[Chen, Yabo; Zhou, Tiejun] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Peng, Zhenyun] Guilin Univ Elect Technol, Guilin 541004, Peoples R China.
通讯机构：
[Zhou, Tiejun] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Iterative method;Least-squares problem;Matrix equation;Matrix nearness problem
摘要：
A new matrix based iterative method is presented to compute common symmetric solution or common symmetric least-squares solution of the pair of matrix equations AXB = E and CXD = F. By this iterative method, for any initial matrix X0, a solution X* can be obtained within finite iteration steps if exact arithmetic was used, and the solution X * with the minimum Frobenius norm can be obtained by choosing a special kind of initial matrix. In addition, the unique nearest common symmetric solution or common symmetric least-squares solution X to given matrix X in Frobenius norm can be obtained by first finding the minimum Frobenius norm common symmetric solution or common symmetric least-squares solution of the new pair of matrix equations. The given numerical examples show that the matrix based iterative method proposed in this paper has faster convergence than the iterative methods proposed in [1,2] to solve the same problems. © 2010 Elsevier Inc. All rights reserved.
语种：
英文
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