稻草秸秆的碱性臭氧预处理效果
作者：
李辉勇;黄可龙;金密;魏琴琴;李志光
期刊：
农业工程学报 ,2010年26(4):264-268 ISSN：1002-6819
通讯作者：
Huang, K.(klhuang@mail.csu.edu.cn)
作者机构：
[李辉勇; 黄可龙] College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;[魏琴琴] Hunan Institute of Agriculture Economy and Regional Planning, Changsha 410125, China;[金密; 李辉勇; 李志光] College of Science, Hunan Agricultural University, Changsha 410128, China
通讯机构：
College of Chemistry and Chemical Engineering, Central South University, China
关键词：
臭氧;稻草;酶水解;扫描电镜;预处理
摘要：
为了研究碱性臭氧预处理对稻草秸秆酶水解、表观结构及成分的影响,将稻草秸秆碱性臭氧预处理后进行酶水解,对处理前后的稻草秸秆进行了扫描电镜观察及成分分析,并对处理后溶液进行了紫外光谱分析. 结果表明:碱性臭氧预处理能将稻草秸秆中的木质素氧化降解为小分子的有机酸,降低了稻草秸秆中木质素的含量,提高了纤维素的含量. 扫描电镜观察显示经碱性臭氧预处理过的稻草秸秆,机械组织暴露,孔隙度大,酶解的有效比表面积大. 在pH值5.0、每单位底物加酶量31.2mg/g、45℃条件下,碱性臭氧预处理稻草秸秆酶水解120h时还原糖达到了902mg/g,糖化率为92.57%. 在相同酶解条件下,碱性预处理与未处理稻草秸秆的糖化率分别为74.90%与53.53%. 碱性臭氧预处理稻草秸秆的糖化率明显高于碱性预处理与未处理稻草秸秆的糖化率
语种：
中文
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Si3N4-doped Zr50Al15Ni10Cu25 glassy alloy by mechanical alloying and sintering process
作者：
Ouyang Xue-qiong;Long Wo-yun;Bian Jian-ze;Gao Chao;Lu An-xian*
期刊：
中南大学学报(英文版) ,2010年17(6):1125-1128 ISSN：2095-2899
通讯作者：
Lu An-xian
作者机构：
[Lu An-xian; Gao Chao; Ouyang Xue-qiong; Long Wo-yun] Cent S Univ, Sch Mat Sci & Engn, Changsha 410083, Hunan, Peoples R China.;[Long Wo-yun] Hunan Agr Univ, Dept Appl Phys, Changsha 410083, Hunan, Peoples R China.;[Bian Jian-ze] Barun Min Co Ltd, Baotou 014080, Peoples R China.
通讯机构：
[Lu An-xian] C;Cent S Univ, Sch Mat Sci & Engn, Changsha 410083, Hunan, Peoples R China.
关键词：
Zr-based metallic glass;mechanical alloying;sintering;activation energy
摘要：
Zr50Al15Ni10Cu25 amorphous powder was synthesized by mechanical alloying. The effect of Si3N4 addition on the crystallization behavior of the alloy during sintering process was studied. Thermal stability of the powders was performed by differential scanning calorimetry (DSC). The phase and microstructure of the powders and bulk specimens sintered were determined by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results show that, introducing 0.05% (mass fraction) Si3N4 can enhance the crystallization activation energy of the Zr50Al15Ni10Cu25 amorphous powders, which indicates that Si3N4 addition has hindrance effect on forming crystals from Zr50Al15Ni10Cu25 amorphous powder. However, 0.10% Si3N4 results in the decrease of the crystallization activation energy, which makes its crystallization process easy to occur.
语种：
英文
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Nonenzymatic glucose sensor based on gold–copper alloy nanoparticles on defect sites of carbon nanotubes by spontaneous reduction
作者：
Liu, Dengyou;Luo, Qimei* ;Zhou, Fuqiang
期刊：
Synthetic Metals ,2010年160(15-16):1745-1748 ISSN：0379-6779
通讯作者：
Luo, Qimei
作者机构：
[Luo, Qimei; Zhou, Fuqiang; Liu, Dengyou] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Luo, Qimei] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Glucose detection;Functional carbon nanotubes;Spontaneous reduction;Catalysis
摘要：
Gold (Au) and copper (Cu) alloy catalysts were deposited on the defect sites of carbon nanotubes by spontaneous reduction among AuCl<inf>4</inf> <sup>-</sup>, Cu<sup>2+</sup> and oxygen-containing functional groups. Compared with AuCu alloy catalysts prepared by adsorption methods and electrochemical deposition methods, AuCu alloy catalysts show excellent catalytic ability to glucose by spontaneous reduction. The linear range of nonenzymatic sensors that were prepared by spontaneous reduction for glucose detection is 0.08-9.26 mM, and detection limit is 4 μM. In addition, there are high sensitivity (22 μA mM<sup>-1</sup>), reproducibility (96%) and stability (95% after 60 days). Selectivity of this nonenzymatic sensor for ascorbic, uric acid and acetaminophen was also obtained. ©2010 Elsevier B.V.
语种：
英文
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Conductive three-dimensional ordered nano-gold film: Ultrasensitive electrochemical sensing platform for clinical immunoassay
作者：
Liu, Dengyou;Gao, Zhixi;Luo, Qimei;Wu, Zai-Sheng*
期刊：
Talanta ,2010年82(4):1175-1180 ISSN：0039-9140
通讯作者：
Wu, Zai-Sheng
作者机构：
[Luo, Qimei; Liu, Dengyou] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Wu, Zai-Sheng] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Gao, Zhixi] Zunyi Normal Coll, Dept Chem, Zunyi 563002, Guizhou, Peoples R China.
通讯机构：
[Wu, Zai-Sheng] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
关键词：
Antibody;Human immunoglobulin G;Three-dimensional ordered nano-gold film;Ultrasensitive electrochemical clinic immunoassay
摘要：
A simple, reusable and ultrasensitive electrochemical clinic immunoassay is proposed via developing a versatile CTDONG (conductive three-dimensional ordered nano-gold) film-modified gold electrode, in which ferrocene derivative and human immunoglobulin G (hIgG) are used as signaling probe and model molecule, respectively. A signal-on signaling mechanism is achieved by utilizing a sandwich format of the primary antibody/hIgG/the secondary antibody labeled with Ferrocene (PAb/Ag/SAb). Owing to the combination of the advantages of CTDONG film with the versatility of ferrocene derivatives, a substantially enhanced signal accompanied by a low background peak current is achieved. By this sensing scheme, target molecule can be readily quantified in a comparatively wide dynamic range (8.1 ×10<sup>-13</sup>-6.2 ×10<sup>-10</sup> M) with a relatively low detection limit (2.7 ×10 <sup>-13</sup> M). In addition to a greatly improved signal gain, this immunosensor gives a favourable reusability and good reproducibility. Moreover, the CTDONG film-based sensing interface shows excellent anti-interference ability to the coexistent proteins. Meanwhile, the recovery test and determination of target molecule in real samples have confirmed the feasibility of designed sensing system for clinic immunoassay of protein molecules, demonstrating the potential application of described CTDONG film in the development of biomolecule assay platforms. ©2010 Elsevier B.V. All rights reserved.
语种：
英文
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C2C E-commerce credit comprehensive evaluation model for multi-factors
作者：
He, Qingquan;Zou, Yuanmei
期刊：
International Conference on Internet Technology and Applications, ITAP 2010 - Proceedings ,2010年
通讯作者：
He, Q.(qingquan_he@126.com)
作者机构：
[He, Qingquan] School of Science, Hunan Agriculture University, Changsha 410128, China;[Zou, Yuanmei] School of Engineering, Hunan Agriculture University, Changsha 410128, China;[He, Qingquan] School of Business, Central South University, Changsha 410083, China
摘要：
This paper analyzes the problems of the main credit evaluation model,and establishs an improved comprehensive evaluation model for C2C e-commerce credit;The improved model is based on the main indicators of the current credit evaluationt: product quality, logistics, and service attitude ,and comprehensive considerates the impact weights of various indicators ;At the same time , We calculate the user's credit with the counterparty creditworthiness number of transactions and transaction amount . For new users, We places the user's level of social credit in place of its initial credit status, and then determine the user's credit rating assessment. This model used to solve the major problems which emerges in current C2C site evaluation model. ©2010 IEEE.
语种：
中文
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Characterization of yeast cells as a microencapsulation wall material by Fourier-transform infrared spectroscopy
作者：
Shi, Guorong* ;Rao, Liqun;Xie, Qingji;Li, Jun;Li, Benxiang;...
期刊：
Vibrational Spectroscopy ,2010年53(2):289-295 ISSN：0924-2031
通讯作者：
Shi, Guorong
作者机构：
[Shi, Guorong; Xiong, Xingyao] Key Lab Hunan Crop Germplasm Innovat & Utilizat, Changsha 410128, Hunan, Peoples R China.;[Li, Jun; Shi, Guorong; Li, Benxiang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Rao, Liqun] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha 410128, Hunan, Peoples R China.;[Xie, Qingji] Hunan Normal Univ, Coll Chem & Chem Engn, Minist Educ China, Key Lab Chem Biol & Tradit Chinese Med Res, Changsha 410081, Hunan, Peoples R China.
通讯机构：
[Shi, Guorong] K;Key Lab Hunan Crop Germplasm Innovat & Utilizat, Changsha 410128, Hunan, Peoples R China.
关键词：
FT-IR spectroscopy;Multivariate analysis;S. cerevisiae;Chlorogenic acid;Microencapsulation
摘要：
The chemically induced structural changes of yeast cells as a wall material for the microencapsulation of chlorogenic acid (CGA) were investigated by the Fourier-transform infrared (FT-IR) spectroscopy. Results indicate that the encapsulation performance of S. cerevisiae cells was largely affected by the composition of the culture medium, and the optimal composition of the culture medium was obtained in terms of the encapsulation yield of CGA. The yeast cells cultured under optimal conditions were subject to chemical treatment by sodium chloride, cetyltrimethylammonium bromide (CTAB), Triton X-100, sodium dodecyl sulfate (SDS) or ethanol. The chemical treatments notably changed the encapsulation properties of S. cerevisiae cells for CGA, with the highest encapsulation yield in the CTAB case. All the chemical treatments decreased the FT-IR absorption bands for proteins and nucleic acids of S. cerevisiae cells but increased those for lipids and fatty acids, and it is thus rather difficult to discuss the relationship between the encapsulation yield and the wall structures derived from the original FT-IR spectra. In contrast, multivariate analyses on the second derivative transformation FT-IR spectra of the yeast cell wall materials indicate that under various culture and chemical treatment conditions, the encapsulation yield of yeast cells for CGA was positively correlated with its IR absorption ratios of 1157 cm<sup>-1</sup> to 1043 cm<sup>-1</sup> (D1157/D1043) and of 1537 cm<sup>-1</sup> to 1043 cm<sup>-1</sup> (D1537/D1043) significantly (p <0.05), whereas negatively correlated with those of 1080 cm<sup>-1</sup> to 1043 cm<sup>-1</sup> (D1080/D1043), 1458 cm<sup>-1</sup> to 1043 cm<sup>-1</sup> (D1458/D1043) and 1740 cm<sup>-1</sup> to 1043 cm <sup>-1</sup> (D1740/D1043) significantly (p <0.05). The five absorption ratios proposed here from the second derivative transformation FT-IR spectra may be a rapid gauge for predicting the encapsulation properties of yeast cells and screening out optimal yeast cells for encapsulation of other species. ©2010 Elsevier B.V. All rights reserved.
语种：
英文
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Surface self-diffusion behavior of a Pt adatom on Wulff polyhedral clusters
作者：
Yang, Jianyu* ;Hu, Wangyu;Chen, Shuguang;Tang, Jianfeng
期刊：
Journal of Physical Chemistry C ,2009年113(52):21501-21505 ISSN：1932-7447
通讯作者：
Yang, Jianyu
作者机构：
[Yang, Jianyu] Hunan Inst Engn, Dept Math & Phys, Xiangtan 411104, Peoples R China.;[Hu, Wangyu; Chen, Shuguang] Hunan Univ, Dept Appl Phys, Changsha 410082, Hunan, Peoples R China.;[Tang, Jianfeng] Hunan Agr Univ, Dept Appl Phys, Changsha 410028, Hunan, Peoples R China.
通讯机构：
[Yang, Jianyu] H;Hunan Inst Engn, Dept Math & Phys, Xiangtan 411104, Peoples R China.
摘要：
The surface diffusion of a single Pt adatom on Wulff polyhedral clusters with 586-9201 atoms is studied, through a combination of the molecular dynamics and nudged elastic band methods. Interatomic interactions are modeled by the embedded atom method. The minimum energy paths are determined, and the energy barriers for an adatom diffusing on the Wulff polyhedral surface are evaluated. Within the studied cluster size range, the energy barrier for an adatom diffusing from the {111} to {100} facet increases with increasing cluster size. From the calculated energy barriers, we conclude that the Wulff polyhedral cluster is the most stable fcc structure, as the cluster has more than about 2000 atoms at 0 K. The calculated characteristic temperatures show that larger icosahedral or octahedral clusters could be formed at higher temperature. In addition, the static and dynamic simulations show that the diffusion from {111} to a neighbor {111} facet is slower than the diffusion from the {111} to {100} facet. ©2009 American Chemical Society.
语种：
英文
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Strain isolation and optimization of process parameters for bioconversion of glycerol to lactic acid
作者：
Hong, An-An;Cheng, Ke-Ke;Peng, Feng;Zhou, Sheng;Sun, Yan;...
期刊：
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY ,2009年84(10):1576-1581 ISSN：0268-2575
通讯作者：
Liu, Can-Ming
作者机构：
[Peng, Feng; Hong, An-An; Liu, Can-Ming] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, De-Hua; Zhou, Sheng; Hong, An-An; Sun, Yan] Tsinghua Univ, Dept Chem Engn, Beijing 100084, Peoples R China.;[Cheng, Ke-Ke] Tsinghua Univ, Inst Nucl & New Energy Technol, Beijing 100084, Peoples R China.
通讯机构：
[Liu, Can-Ming] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
lactic acid;screening;fermentation;glycerol;optimization;Escherichia coli
摘要：
BACKGROUND: The crude glycerol from biodiesel production represents an abundant and inexpensive source which can be used as raw material for lactic acid production. The first aim of this investigation was to select a strain suitable for producing lactic acid from glycerol with a high concentration and productivity. The second aim was to obtain the optimum fermentation conditions, as a basis for large-scale lactate production in the future. RESULTS: Eight bacterial strains, which could aerobically convert glycerol to lactic acid, were screened from soil samples. One of the strains, AC-521, which synthesized lactic acid with a higher concentration, was identified based on its 16S rDNA sequences and physiological characteristics. These results indicated that this strain was a member of Escherichia coli. The optimal fermentation conditions for Escherichia coli AC-521 were 42°C, pH 6.5, 0.85 min<sup>-1</sup> (K <inf>L</inf>a). CONCLUSION: Escherichia coli AC-521 suitable for producing lactic acid from glycerol with high concentration and productivity was identified. After 88 h of fed-batch fermentation, both the lactic acid concentration and glycerol consumption reached maximum, giving 85.8 g L <sup>-1</sup> of lactic acid with a productivity of 0.97 g L<sup>-1</sup> h <sup>-1</sup> and a yield of 0.9 molmol<sup>-1</sup> glycerol. ©2009 Society of Chemical Industry.
语种：
英文
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Direct synthesis of micro-coiled carbon fibers on graphite substrate using co-electrodeposition of nickel and sulfur as catalysts
作者：
Liu, Dengyou* ;Luo, Qimei;Wang, Huixian;Chen, Jinhua
期刊：
Materials & Design ,2009年30(3):649-652 ISSN：0264-1275
通讯作者：
Liu, Dengyou
作者机构：
[Luo, Qimei; Liu, Dengyou; Wang, Huixian] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Chen, Jinhua] Hunan Univ, Coll Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Liu, Dengyou] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Micro-coiled carbon fibers;Catalysts;Electrochemical deposition;Sulfur;Chemical vapour deposition;Scanning electron microscopy
摘要：
Micro-coiled carbon fibers were directly prepared on the graphite substrate using co-electrodeposition of nickel and sulfur as catalysts, in this paper. The diameter of coil and that of micro-coiled carbon fiber are about 800 nm and 400 nm, respectively. Compared with the current preparation methods of catalysts, electrochemical deposition is an effective, cheap and simple technique. Especially, this method is suitable for preparation of ally catalyst. The parameters of electrochemical deposition (deposition time and current density) have little influence on helix of growth and growth mechanism of carbon fibers. By adjusting the electrolyte solution, the amount of sulfur in catalyst are easily carried out, and it is found that sulfur content in catalyst plays an important role on morphological characteristics of carbon fibers.
语种：
英文
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A new criterion to global exponential periodicity for discrete-time BAM neural network with infinite delays
作者：
Zhou, Tiejun* ;Liu, Yuehua;Li, Xiaoping;Liu, Yirong
期刊：
CHAOS SOLITONS & FRACTALS ,2009年39(1):332-341 ISSN：0960-0779
通讯作者：
Zhou, Tiejun
作者机构：
[Liu, Yuehua; Li, Xiaoping; Zhou, Tiejun] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Yirong; Zhou, Tiejun] Cent S Univ, Sch Math, Changsha 410000, Hunan, Peoples R China.
通讯机构：
[Zhou, Tiejun] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
摘要：
The discrete-time bidirectional associative memory neural network with periodic coefficients and infinite delays is studied. And not by employing the continuation theorem of coincidence degree theory as other literatures, but by constructing suitable Liapunov function, using fixed point theorem and some analysis techniques, a sufficient criterion is obtained which ensures the existence and global exponential stability of periodic solution for the type of discrete-time BAM neural network. The obtained result is less restrictive to the BAM neural networks than previously known criteria. Furthermore, it can be applied to the BAM neural network which signal transfer functions are neither bounded nor differentiable. In addition, an example and its numerical simulation are given to illustrate the effectiveness of the obtained result. © 2007 Elsevier Ltd. All rights reserved.
语种：
英文
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Sensitive label-free electrochemical immunoassay by electrocatalytic amplification
作者：
Chen, Chenrui;Liu, Dengyou;Wu, Zaisheng* ;Luo, Qimei;Shen, Guo-Li;...
期刊：
Electrochemistry Communications ,2009年11(10):1869-1872 ISSN：1388-2481
通讯作者：
Wu, Zaisheng
作者机构：
[Chen, Chenrui; Shen, Guo-Li; Yu, Ru-Qin; Wu, Zaisheng] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Luo, Qimei; Liu, Dengyou] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Wu, Zaisheng] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
关键词：
Human immunoglobulin E (IgE);Methylene blue (MB);Gold nanoparticles (GNPs)
摘要：
A label-free electrochemical immunosensor for the detection of protein analytes without redox-active centers is for the first time developed based on the combination of gold nanoparticles and the mediated charge transport through the multilayer films that is related to an electrocatalytic process. Given the low detection limit, high sensitivity and selectivity, the success achieved here seems plausibly to serve as a significant step toward the development of versatile label-free immunoassay.
语种：
英文
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Enhancement of the enzymatic digestibility of sugarcane bagasse by alkali–peracetic acid pretreatment
作者：
Zhao, Xuebing* ;Peng, Feng;Cheng, Keke;Liu, Dehua
期刊：
Enzyme and Microbial Technology ,2009年44(1):17-23 ISSN：0141-0229
通讯作者：
Zhao, Xuebing
作者机构：
[Zhao, Xuebing; Liu, Dehua] Tsinghua Univ, Dept Chem Engn, Inst Appl Chem, Beijing 100084, Peoples R China.;[Peng, Feng] Hunan Agr Univ, Coll Sci, Changsha 410028, Peoples R China.;[Cheng, Keke] Tsinghua Univ, Inst Nucl & New Energy Technol, Beijing 100084, Peoples R China.
通讯机构：
[Zhao, Xuebing] T;Tsinghua Univ, Dept Chem Engn, Inst Appl Chem, Beijing 100084, Peoples R China.
关键词：
Sugarcane bagasse;Pretreatment;Alkaline swelling;Peracetic acid;Delignification;Enzymatic digestibility
摘要：
The enzymatic digestibility of sugarcane bagasse was greatly increased by alkali (NaOH)-peracetic acid (PAA) pretreatment under mild conditions. The effects of several factors affecting the pretreatment were investigated. It was found that when bagasse was pre-pretreated by 10% (based on initial dry materials) NaOH with 3:1 liquid-to-solid ratio at 90 °C for 1.5 h and further delignified by 10% peracetic acid (based on initial dry materials) at 75 °C for 2.5 h, the yield of reducing sugars reached 92.04% by enzymatic hydrolysis for 120 h with cellulase loading of 15 FPU/g solid. Compared with acid and alkali pretreatment, alkali-PAA pretreatment could be conducted under milder conditions and was more effective for delignification with less carbohydrates being degraded in the pretreatment process. Alkaline stage played an important role for partial delignification, swelling fibers and subsequently reducing PAA loading. No loss of cellulase activity (FPA) was observed in the liquid phase for alkali-PAA pretreated bagasse after enzymatic hydrolysis for 120 h. © 2008 Elsevier Inc. All rights reserved.
语种：
英文
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补偿模糊神经网络水果形状分级器分级误差
作者：
曹乐平;温芝元
期刊：
农业工程学报 ,2008年24(12):102-106 ISSN：1002-6819
通讯作者：
Cao, L.(clp4218@126.com)
作者机构：
[曹乐平] Hunan Biological and Electromechanical Polytechnic, Changsha 410127, China;[温芝元] College of Science, Hunan Agricultural University, Changsha 410128, China
通讯机构：
Hunan Biological and Electromechanical Polytechnic, China
关键词：
补偿模糊神经网络;离散傅里叶变换;谐波分量;水果形状;分级误差
摘要：
针对神经网络对水果进行分级时精度有待提高的问题,分析了补偿模糊神经网络椪柑形状分级器的分级误差。将椪柑图像前4个傅里叶描述子按期望输出模糊变量值大小排列成单调递增、单调递减、钟形分布和锯齿形分布4种训练样本,分别训练同一补偿模糊神经网络水果形状分级器,用递减排序后的同一测试样本检验分级器性能,试验表明,单调递减顺序训练样本所训练的分级器分级误差最小为1.875%,钟形分布、单调递增顺序和锯齿形分布训练样本所训练的分级器分级误差依次增大,分别为15%、63.125%、75%。分析分级误差与样本间顺序的对应关系,建立分级误差模型,结果表明,同顺序的测试样本与训练样本间相关系数大,分级误差小;不同顺序的测试样本与训练样本间相关系数小,分级误差大。因此,测试样本与训练样本按水果同一品质特征同序排列,提高样本间的相关程度,将大幅度降低神经网络类分级器分级误差,提高正确识别率。
语种：
中文
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An Approach to Resolving Two Paradoxes in Probability Theory
作者：
刘道建;黄天民;陈亚波
期刊：
上海交通大学学报(英文版) ,2008年13(3):362-365 ISSN：1007-1172
通讯作者：
Liu, D.-J.(djliu2008@163.com)
作者机构：
[刘道建] School of Mathematics and Computing Science, Hunan University of Science and Technology, Xiangtan 411201, China;[陈亚波] Science College, Hunan Agricultural University, Changsha 410128, China;[刘道建; 黄天民] School of Electrical Engineering, Southwest Jiaotong University, Chengdu 610031, China
通讯机构：
[Dao-jian Liu] S;School of Mathematics and Computing Science, Hunan University of Science and Technology, Xiangtan, China<&wdkj&>School of Electrical Engineering, Southwest Jiaotong University, Chengdu, China
关键词：
conservative probability function;conservation degree;conservative mathematical expectation;St. Petersburg paradox and Pascal＇s wager;convergence;group decision-making
摘要：
A new mathematical expectation formula with some hypotheses, notions and propositions was given to get rid of the challenge of St. Petersburg paradox and Pascal's wager. Relevant results show that it is very effective to apply the model to solve the expected revenue problems containing random events with low probability but high revenue. This work also provides the probability theory with a more widely applied perspective in group decision-making.
语种：
英文
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Diffusion Dynamics of Cu_x Cluster on Cu(111) Surface
作者：
Tang, Jian-Feng* ;Xu, Mai-Chang;Li, Xue-Song;Long, Wo-Yun
期刊：
化学物理学报(英文版) ,2008年21(1):27-31 ISSN：1674-0068
通讯作者：
Tang, Jian-Feng
作者机构：
[Tang, Jian-Feng; Li, Xue-Song; Long, Wo-Yun] Hunan Agr Univ, Dept Appl Phys, Changsha 410128, Peoples R China.;[Xu, Mai-Chang] Hunan Inst Engn, Dept Math & Phys, Xiangtan 411104, Peoples R China.
通讯机构：
[Tang, Jian-Feng] H;Hunan Agr Univ, Dept Appl Phys, Changsha 410128, Peoples R China.
关键词：
Cluster;Molecular dynamics;Surface diffusion
摘要：
The diffusion dynamics of small two-dimensional atomic clusters Cu x (1 x 8) on Cu(111) surface were studied using the molecular dynamics simulations and a modified analytic embedded-atom method in the temperature range from 200 K to 800 K. The cluster size and temperature dependence of the diffusion coefficients and migration energies are presented. Our simulations show that the diffusion migration energy of the Cu7 cluster is the highest and the prefactor for the Cu7 cluster is almost three orders of magnitude larger than that for single atom diffusion. This conclusion is consistent with the experimental results for similar metals. In addition, the dependence of cluster diffusion on film growth is also discussed. © 2008 Chinese Physical Society.
语种：
英文
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Statistical optimization of culture conditions for 1,3-propanediol by Klebsiella pneumoniae AC 15 via central composite design
作者：
Zheng, Zong-Ming;Hu, Qiu-Iong;Hao, Jian;Xu, Feng;Guo, Ni-Ni;...
期刊：
Bioresource Technology ,2008年99(5):1052-1056 ISSN：0960-8524
通讯作者：
Liu, De-Hua
作者机构：
[Liu, De-Hua; Xu, Feng; Hao, Jian; Guo, Ni-Ni; Sun, Yan; Zheng, Zong-Ming] Tsinghua Univ, Dept Chem Engn, Beijing 100084, Peoples R China.;[Hu, Qiu-Iong] Hunan Agr Univ, Coll Sci, Changsha 410218, Peoples R China.
通讯机构：
[Liu, De-Hua] T;Tsinghua Univ, Dept Chem Engn, Beijing 100084, Peoples R China.
关键词：
1,3-PD;CCD;Klebsiella pneumoniae;Optimization;RSM
摘要：
A central composite design was used to study the effect of glycerol, rate of stirring, air aeration and pH on the synthesis of 1,3-propanediol (1,3-PD) by Klebsiella pneumoniae AC 15. Among the four variables, glycerol and rate of stirring significantly affected 1,3-PD productivity, whereas air aeration and pH were not effective. A quadratic polynomial equation was obtained for 1,3-PD productivity by multiple regression analysis using response surface methodology. The validation experimental confirmed with the predicted model. The optimum combinations for 1,3-PD productivity was glycerol, rate of stirring, air aeration, and pH of 50 g/l, 318 rpm, 0.6 vvm, 6.48, respectively. The subsequent fed batch experiments produced 1,3-PD of 70 g/l at a fermentation of 30 h. © 2007 Elsevier Ltd. All rights reserved.
语种：
英文
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Fast-response and high sensitivity gas sensors based on SnO2 hollow spheres
作者：
Tan, Yu* ;Li, Chengchao;Wang, Yong;Tang, Jianfeng;Ouyang, Xicheng
期刊：
Thin Solid Films ,2008年516(21):7840-7843 ISSN：0040-6090
通讯作者：
Tan, Yu
作者机构：
[Tan, Yu; Li, Chengchao] Hunan Univ, Micronano Technol Res Ctr, Changsha 410082, Hunan, Peoples R China.;[Ouyang, Xicheng; Tan, Yu; Tang, Jianfeng; Wang, Yong] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Tan, Yu] H;Hunan Univ, Micronano Technol Res Ctr, Changsha 410082, Hunan, Peoples R China.
关键词：
Gas sensors;Hollow spheres;Recovery;Response;Sensitivity;SnO2
摘要：
SnO<sub>2</sub> hollow nanospheres have been synthesized by heat treatment of a mixture composed of SnCl<sub>4</sub> and carbon microspheres. The SnO<sub>2</sub> nanospheres are 100 nm in size and composed of large amount of SnO<sub>2</sub> nanocrystals with diameters of ~ 6 nm, which is close to two times of the Debye length of SnO<sub>2</sub>. It was found that the sensitivity to 1000 ppm ethanol obtained with SnO<sub>2</sub> hollow nanosphere-based sensors is as high as 75. The response and recovery time are only 4 and 10 s, respectively. Such excellent sensing properties can be ascribed to the small-size nanocrystals and porous structure of SnO<sub>2</sub> hollow nanospheres, which lead to large diffusion constant. ©2008 Elsevier B.V. All rights reserved.
语种：
英文
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酸处理改善1,3-丙二醇发酵液过滤效果的研究
作者：
曾凡佳;郝健;刘灿明;刘德华
期刊：
化学工程 ,2008年36(3):52-56 ISSN：1005-9954
通讯作者：
Zeng, F.-J.(zengfanjia9910108@163.com)
作者机构：
[曾凡佳; 刘灿明] 湖南农业大学理学院;[郝健; 刘德华] 清华大学化工系;清华大学化工系 湖南长沙410128;北京100084
通讯机构：
College of Sciences, Hunan Agricultural University, China
关键词：
1,3-丙二醇;发酵液;过滤;预处理;克雷伯氏肺炎杆菌
摘要：
克雷伯氏肺炎杆菌TUAC01产1,3-丙二醇生发酵液不能通过絮凝或过滤的方法得到澄清。研究采取酸处理的方法进行澄清,结果表明,酸处理后发酵液可经过滤进行澄清,同时发酵液还能自然沉降澄清。酸处理最适操作条件为：温度80—100℃、pH值为3.0、时间30—60 min。发酵液酸处理后滤纸过滤清液OD_(650)降为0.01,降低了99.9%,黏度下降明显,其粘滞系数降为0.001 5 Pa.s;蛋白质质量浓度降低至0.05 mg/mL,降低了98%—99%。该酸处理方法经车间大规模实践,效果理想,可作为带荚膜菌种发酵所得发酵液的澄清处理方法。
语种：
中文
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Global exponential periodicity for BAM neural network with periodic coefficients and continuously distributed delays
作者：
Zhou, Tiejun* ;Liu, Yuehua;Li, Xiaoping;Liu, Yirong
期刊：
Computers & Mathematics with Applications ,2008年55(11):2689-2698 ISSN：0898-1221
通讯作者：
Zhou, Tiejun
作者机构：
[Liu, Yuehua; Li, Xiaoping; Zhou, Tiejun] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Yirong; Zhou, Tiejun] Cent S Univ, Sch Math, Changsha 410000, Hunan, Peoples R China.
通讯机构：
[Zhou, Tiejun] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
BAM neural network;Continuously distributed delay;Global exponential stability;Lyapunov function;Periodic solution
摘要：
By constructing a suitable Lyapunov function and using some analysis techniques, rather than employing the continuation theorem of coincidence degree theory as in other literature, a sufficient criterion is obtained to ensure the existence and global exponential stability of periodic solution for the bidirectional associative memory neural network with periodic coefficients and continuously distributed delays. The obtained result is less restrictive to the BAM neural network than the previously known criteria. And it can be applied to the BAM neural network in which signal transfer functions are neither bounded nor differentiable. In addition, an example and its numerical simulation are given to illustrate the effectiveness of the obtained result. © 2007 Elsevier Ltd. All rights reserved.
语种：
英文
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Multi-KNN-SVR组合预测在含氟化合物QSAR研究中的应用
作者：
Tan Xian-Sheng;Yuan Zhe-Ming* ;Zhou Tie-Jun;Wang Chun-Juan;Xiong Jie-Yi
期刊：
高等学校化学学报 ,2008年29(1):95-99 ISSN：0251-0790
通讯作者：
Yuan Zhe-Ming
作者机构：
[Wang Chun-Juan; Tan Xian-Sheng; Xiong Jie-Yi; Yuan Zhe-Ming] Hunan Agr Univ, Coll Biosafety Sci & Technol, Changsha 410128, Peoples R China.;[Zhou Tie-Jun; Tan Xian-Sheng] Hunan Agr Univ, Coll Sci, Changsha 410128, Peoples R China.
通讯机构：
[Yuan Zhe-Ming] H;Hunan Agr Univ, Coll Biosafety Sci & Technol, Changsha 410128, Peoples R China.
关键词：
含氟化合物;支持向量回归;定量构效关系;K-最近邻;组合预测
摘要：
为深入认识含氟农药生物活性与其结构之间的关系，建立了理想的QSAR模型，从化合物油水分配系数等7个分子结构描述符出发，基于支持向量回归（SVR）和MSE最小原则，经自动寻找最优核函数和非线性筛选描述符，构建了多个K-最近邻（KNN）预测子模型．再经非线性筛选获得保留子模型，以保留子模型实施组合预测（Multi—KNN—SVR）．33种含氟化合物对5种不同病害生物活性的留一法组合预测结果表明，采用非线性筛选描述符和KNN子模型能有效地提高预测精度，基于多个KNN子模型的非线性组合能进一步提高预测性能．Multi—KNN—SVR组合预测在QSAR以及其它相关预测研究中具有广泛应用前景．
语种：
中文
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