Molecular dynamics simulation of cylindrically converging shock response in single crystal Cu
作者：
Tang, Fang;Jian, Zhiyong;Xiao, Shifang* ;Li, Xiaofan;Wang, Liang;...
期刊：
计算材料学(英文) ,2020年183:109845 ISSN：2057-3960
通讯作者：
Xiao, Shifang
作者机构：
[Xiao, Shifang; Deng, Huiqiu; Li, Xiaofan; Tang, Fang; Jian, Zhiyong] Hunan Univ, Sch Phys & Elect, Dept Appl Phys, Changsha 410082, Hunan, Peoples R China.;[Wang, Liang] Hunan Agr Univ, Coll Sci, Changsha 410128, Peoples R China.;[Huang, Bowen; Hu, Wangyu] Hunan Univ, Coll Mat Sci & Engn, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Xiao, Shifang] H;Hunan Univ, Sch Phys & Elect, Dept Appl Phys, Changsha 410082, Hunan, Peoples R China.
关键词：
Cylindrical converging impact;Dislocation loops;Molecular dynamics simulation;Plasticity deformation;Temperature distribution
摘要：
There are tremendous experimental and simulation studies with regard to the shock response of copper, however, it is believed that the published literatures are seldom focused on response behavior of copper under nonplanar shock loading. Combined with the interaction between a potential wall and atoms, molecular dynamics simulation is performed to investigate the shock response of single crystal Cu under cylindrically converging impact, with the axis of a cylindrical potential wall along the [0 0 1] crystallographic orientation. The results show that affected by anisotropy of wave speed, the surface shape of elastic wavefront is transformed into a quadrangular columnar form from the initial cylindrical one. With the same shock velocity, due to the converging effect, the temperature rise under cylindrical impact is higher than that under planar impact, and the temperature distribution is very complex during shock. The sites for dislocation nucleation are dependent on shock velocity. At the shock velocity of 0.4 km/s, the nucleation and activity of Shockley partial dislocation loops occur in the hot spot regions adjacent to shock front along [1 0 0] and [0 1 0] directions. As shock velocity increases to 0.55 km/s, the shock plasticity starts from the free surface along [1 1 0] and [1–10] directions. © 2020 Elsevier B.V.
语种：
英文
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Reactions of 2-aza-21-carbaporphyrin with aniline derivatives
作者：
Ren, Demin;Liu, Bin;Li, Xiaofang* ;Koniarz, Sebastian;Pawlicki, Milosz;...
期刊：
Organic Chemistry Frontiers ,2019年6(7):908-918 ISSN：2052-4110
通讯作者：
Li, Xiaofang;Chmielewski, Piotr J.
作者机构：
[Ren, Demin] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Bin; Li, Xiaofang] Hunan Univ Sci & Technol, Sch Chem & Chem Engn, Minist Educ, Key Lab Theoret Organ Chem & Funct Mol, Xiangtan 411201, Hunan, Peoples R China.;[Koniarz, Sebastian; Pawlicki, Milosz; Chmielewski, Piotr J.] Univ Wroclaw, Dept Chem, F Joliot Curie 14, PL-50383 Wroclaw, Poland.
通讯机构：
[Li, Xiaofang] H;[Chmielewski, Piotr J.] U;Hunan Univ Sci & Technol, Sch Chem & Chem Engn, Minist Educ, Key Lab Theoret Organ Chem & Funct Mol, Xiangtan 411201, Hunan, Peoples R China.;Univ Wroclaw, Dept Chem, F Joliot Curie 14, PL-50383 Wroclaw, Poland.
关键词：
Stereochemistry;Aniline derivatives;Aromatic amines;Chloranil;One pot;One step synthesis;Organic Chemistry;Redox property;Regio-selective;Aniline
摘要：
Regioselective azotization or bis(amination) products of the title porphyrinoid were achieved in one-pot one-step syntheses under mild conditions using a selection of aromatic amines and isoamyl nitrite or p-chloranil, respectively. Structures, tautomery, chirality as well as spectroscopic and redox properties of the new systems were discussed.
语种：
英文
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微信辅助BOPPPS教学模型在有机化学课程教学中的应用研究
作者：
李霞;文志勇;李宇;张薇;董新容
期刊：
科技经济导刊 ,2019年(24):112-113 ISSN：2096-1995
作者机构：
湖南农业大学理学院
关键词：
BOPPPS教学模型;微信;有机化学课程
摘要：
以湖南农业大学"有机化学"课程为例,分析传统教学在新教学模式下存在的问题,结合BOPPPS教学模型,进行微信辅助有机化学课程教学方面的研究。
语种：
中文
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High-density sodium vanadate nanowires on substrate coated with polypyrrole for lithium-ion battery
作者：
Hua, Kang;Li, Xiujuan;Fang, Dong* ;Yi, Jianhong;Wu, Xiongwei;...
期刊：
Materials Science and Engineering B-Advanced Functional Solid-State Materials ,2018年238-239:26-35 ISSN：0921-5107
通讯作者：
Fang, Dong
作者机构：
[Fang, Dong; Hua, Kang; Yi, Jianhong; Li, Xiujuan] Kunming Univ Sci & Technol, Fac Mat Sci & Engn, Kunming 650093, Yunnan, Peoples R China.;[Xu, Weilin; Fang, Dong; Cai, Ziqing; Hua, Kang; Li, Xiujuan; Jiang, Ming] Wuhan Text Univ, Coll Mat Sci & Engn, Minist Educ, Key Lab Green Proc & Funct Text New Text Mat, Wuhan 430200, Hubei, Peoples R China.;[Wu, Xiongwei] Hunan Agr Univ, Coll Sci, Changsha, Hunan, Peoples R China.;[Luo, Zhiping] Fayetteville State Univ, Dept Chem & Phys, Fayetteville, NC 28301 USA.;[Wang, Shan] Wuhan Univ Technol, Coll Mat Sci & Engn, Wuhan 430070, Hubei, Peoples R China.
通讯机构：
[Fang, Dong] K;Kunming Univ Sci & Technol, Fac Mat Sci & Engn, Kunming 650093, Yunnan, Peoples R China.
关键词：
Cathodes;Crystal structure;Electric discharges;Electrodeposition;Ions;Morphology;Nanowires;Polypyrroles;Sodium;Crystals structures;Current-collector;Deposition time;Deposition voltage;Electrodeposited-hydrothermal method;Hydrothermal methods;Nanowires films;Sodium vanadate;Sodium vanadate nanowire;Ti foil;Lithium-ion batteries
摘要：
A novel electrodeposited-hydrothermal method has been developed to fabricate high-density β-Na0.33V2O5 nanowire film on a metal current collector (Ti foil). The morphology, crystal structure, and the effects of deposition voltage, temperature and time on the prepared samples were tested and presented in detail. The thickness of the β-Na0.33V2O5 nanowire film was ∼10.5 μm under experimental conditions of 5 h time, 2.5 V voltage, and 90 °C temperature. When the β-Na0.33V2O5 nanowire film was coated with polypyrrole and served as a cathode of lithium-ion battery, it exhibited a high reversible discharge capacity of 269.9 mAh g−1 at a current density of 50 mA g−1. By contrast, the cycling behavior of this material is proved to be much better than the bare β-Na0.33V2O5 nanowire film. This research provides a new pathway to explore high tap density cathode materials for lithium-ion battery with enhanced electrochemical performance. © 2018
语种：
英文
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Global exponential stability of cohen-grossberg neural networks with time-varying delays
作者：
Wang X.;Li X.;Zhou W.
期刊：
Italian Journal of Pure and Applied Mathematics ,2018年(40):126-140 ISSN：1126-8042
通讯作者：
Li, X.
作者机构：
[Wang X.; Li X.; Zhou W.] College of Science, Hunan Agricultural University, Changsha, Hunan, 410128, China
通讯机构：
College of Science, Hunan Agricultural University, Changsha, Hunan, China
关键词：
Time delay;Time varying control systems;Time varying networks;Cohen-Grossberg neural networks;Global exponential stability;M-matrices;Nonlinear measure;Time varying- delays;Neural networks
摘要：
In this paper, without the assumptions for boundedness, monotonicity, and differentiability on activation functions and symmetry of interconnections, a class of Cohen-Grossberg neural networks with time-varying delays is studied. A new useful criteria on the uniqueness of equilibrium is obtained by utilizing the nonlinear measure. Combining with Dini derivatives and Young inequality, new sufficient condition for the global exponential stability is established by directly estimating the upper bound of solutions of the system. All results are presented in M-matrix form, which extended and generalized the corresponding results in previous literature. © 2018 Forum-Editrice Universitaria Udinese SRL. All rights reserved.
语种：
英文
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Theoretical Model of Time–Temperature Superposition Principle of the Self-Healing Kinetics of Supramolecular Polymer Nanocomposites
作者：
Zheng, Zijian;Xia, Xiuyang;Zeng, Xianxiang;Li, Xiu;Wu, Youping;...
期刊：
Macromolecular Rapid Communications ,2018年39(20):e1800382 ISSN：1022-1336
通讯作者：
Liu, Jun;Zhang, Liqun
作者机构：
[Li, Xiu; Zhang, Liqun; Xia, Xiuyang; Wu, Youping; Zeng, Xianxiang; Zheng, Zijian; Liu, Jun; Zhang, LQ] Beijing Univ Chem Technol, Key Lab Beijing City Preparat & Proc Novel Polyme, Beijing 100029, Peoples R China.;[Zheng, Zijian] Hubei Univ, Hubei Collaborat Innovat Ctr Adv Organ Chem Mat, Key Lab Green Preparat & Applicat Funct Mat,Minis, Hubei Key Lab Polymer Mat,Sch Mat Sci & Engn, Wuhan 430062, Hubei, Peoples R China.;[Zeng, Xianxiang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Li, Xiu] Guilin Univ Technol Nanning, Dept Mech & Control Engn, Fusui 532100, Peoples R China.
通讯机构：
[Liu, J; Zhang, LQ] B;Beijing Univ Chem Technol, Key Lab Beijing City Preparat & Proc Novel Polyme, Beijing 100029, Peoples R China.
关键词：
Fracture mechanics;Molecular dynamics;Nanocomposites;Controllable morphology;Molecular dynamics simulations;Polymer nanocomposite;Polymer-grafted nanoparticles;Self-healing;Supramolecular polymers;Temperature superposition;Time temperature superposition;Polymer matrix composites;nanocomposite;nanoparticle;polymer;chemistry;kinetics;molecular dynamics;temperature;theoretical model;Kinetics;Models, Theoretical;Molecular Dynamics Simulation;Nanocomposites;Nanoparticles;Polymers;Temperature
摘要：
The matrix-free polymer nanocomposites (PNCs) formed by polymer-grafted nanoparticles(NPs) gain enormous attention due to their controllable morphology and robust properties. Herein, through molecular dynamics simulation, such PNCs are successfully constructed, and the dispersion state of the NPs can be tailored by varying the grafting density. By manipulating the interaction strength between the end groups of the grafted polymer chains, the tensile fracture behavior and the chain orientation are examined. It is revealed that both of them fall down at large strain because of the propagation of the cavities. By probing the self-healing kinetics at various self-healing temperature and time, a time−temperature superposition principle, similar to the Williams, Landel and Ferry equation, is proposed. These results could provide some fundamental guidelines for the design and fabrication of high performance PNCs with excellent self-healing functionality. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
语种：
英文
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胆碱-组氨酸离子液体提取栀子苷的方法
作者：
张越;李霞;董新荣
期刊：
广州化工 ,2017年(19):68-72 ISSN：1001-9677
作者机构：
[张越; 李霞; 董新荣] 湖南农业大学理学院
关键词：
栀子;栀子苷;胆碱-组氨酸盐;离子液体;提取
摘要：
研究了胆碱-组氨酸（Ch OH-His）离子液体水溶液提取栀子苷的方法。通过单因素实验和正交实验优化了胆碱-组氨酸（Ch OH-His）离子液体水溶液提取栀子粉中栀子苷的条件。结果表明,在胆碱-组氨酸（Ch OH-His）离子液体水溶液浓度为1.5%、料液比为1∶20 g/m L、提取温度为120℃、提取时间为1.5 h的条件下,栀子苷的收率达到19.53%,比50%乙醇提取的收率（14.54%）高出34.3%。
语种：
中文
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The recurrence set arising in α-Lüroth transformation
作者：
Shen, Luming* ;Li, Xinqiang
期刊：
Journal of Number Theory ,2016年159:76-88 ISSN：0022-314X
通讯作者：
Shen, Luming
作者机构：
[Shen, Luming; Li, Xinqiang] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Shen, Luming] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
alpha-Luroth expansion;Recurrence set;Hausdorff dimension
摘要：
Let α = {An}n≥1 be a sequence of left-open and right-closed intervals which partition (0, 1]. The α-Lüroth transformation Lα is defined as an infinite piecewise linear map which maps An linearly onto (0, 1] for every n ≥ 1. Then every point x ∈ (0, 1] is attached with a finite or infinite integer sequence {ℓn}n≥1 by looking at the coding of its trajectory. In this note, we consider the size of the recurrent set in such a system. More precisely, let x0 ∈(0, 1] with an infinite α-Lüroth expansion, and {tn}n≥1 an arbitrary non-decreasing sequence of natural numbers. The recurrence set of α-Lüroth transformation Lα is defined as F(x0)={x ∈[0,1]: Lαn(x)∈ A (ℓ1, ℓ2, ...,ℓtn)(x0), F (x0)= infinitely often n ∈ N}, where A(ℓ1, ℓ2, ...ℓtn)(x0) denotes the tn-th cylinder containing x0 in α-Lüroth expansion. The Hausdorff dimension of F(x0) is obtained. © 2015 Elsevier Inc.
语种：
英文
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α-淀粉酶酶解紫甘薯糖化效果及色素提取的研究
作者：
张杨波;李蕾;李霞;董新荣
期刊：
中国酿造 ,2016年35(4):145-148 ISSN：0254-5071
作者机构：
湖南农业大学理学院,湖南长沙,410128;[张杨波; 李蕾; 董新荣; 李霞] 湖南农业大学
关键词：
紫甘薯;α-淀粉酶;色素
摘要：
该文研究了α-淀粉酶处理紫甘薯,同时获得糖化液与色素的方法。考察了α-淀粉酶用量、酶解温度、酶解时间、料液比对提取紫甘薯色素及糖化效果的影响。结果表明,酶用量35 mg/g、酶解温度80℃、酶解时间1.0 h、料液比1∶5（g∶m L）,提取两次,紫甘薯色素的提取率达85.72%,提取液中总糖质量浓度（以葡萄糖计）为68.20 mg/L,紫甘薯的酶解率达到91.65%。α-淀粉酶糖化处理紫甘薯获得色素与糖化液的方法,操作简单,为紫甘薯的综合利用提供了参考。
语种：
中文
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赖氨酸磷酸盐水溶液提取紫薯色素的研究
作者：
刘玮;王华平;李霞;董新荣
期刊：
化学与生物工程 ,2015年(12):42-46 ISSN：1672-5425
作者机构：
湖南农业大学理学院,湖南 长沙,410128;[刘玮; 王华平; 董新荣; 李霞] 湖南农业大学
关键词：
氨基酸离子液体;赖氨酸磷酸盐;紫薯色素;提取
摘要：
制备了20种氨基酸离子液体，筛选出提取效果最好的赖氨酸磷酸盐型离子液体用于紫薯色素的提取，并考察了赖氨酸磷酸盐水溶液浓度、料液比、提取温度、提取时间对紫薯色素提取的影响，通过单因素实验和正交实验优化紫薯色素的提取工艺。结果表明，在赖氨酸磷酸盐水溶液浓度为2．0％、料液比为1∶10（g∶mL）、提取温度为40℃、提取时间为20 min 时，紫薯色素的提取效果最好。
语种：
中文
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桂花果实油脂脂肪酸组成的GC-MS分析
作者：
赵彩屹;何荞玲;李霞;董新荣
期刊：
化学工程师 ,2015年29(8):25-26+41 ISSN：1002-1124
作者机构：
湖南农业大学理学院,湖南长沙,410128;[何荞玲; 赵彩屹; 董新荣; 李霞] 湖南农业大学
关键词：
桂花果实;油脂;脂肪酸;气相色谱-质谱
摘要：
采用索氏提取法提取桂花果实核仁中的油脂,通过GC-MS分析油脂中脂肪酸的组成及含量。结果显示,桂花果实核仁油脂中鉴定9种脂肪酸,主要包含油酸（39.04%）、亚油酸（33.15%）、棕榈酸（10.31%）、硬脂酸（3.80%）、9,12-十八二烯酸（4.62%）和γ-亚麻酸（6.44%）。其中油酸和亚油酸等不饱和脂肪酸含量高达83.25%。桂花果实核仁中油脂的不饱和脂肪酸含量高,具有良好的应用前景。
语种：
中文
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一种简易同时蒸馏萃取方法用于八角茴香挥发油提取及其GC-MS分析
作者：
孙玉琼;夏东海;董新荣;李霞
期刊：
应用化学 ,2015年32(3):356-361 ISSN：1000-0518
作者机构：
[孙玉琼; 夏东海; 董新荣; 李霞] 湖南农业大学理学院
关键词：
同时蒸馏萃取;水蒸汽蒸馏;气相色谱/质谱;挥发油;八角茴香
摘要：
设计了一种简易同时蒸馏萃取(SSDE)装置并用于八角茴香挥发油提取及其气相色谱-质谱法(GC-MS)分析。该装置由圆底烧瓶、恒压滴液漏斗和回流冷凝管构成。通过对八角茴香挥发油组分的GC-MS分析, 比较SSDE法和水蒸汽蒸馏提取法(HD)提取植物源挥发油的效果。结果表明, SSDE法所得挥发油相对含量在0. 1%以上的19种化合物占挥发油总量的98. 84%(相对标准偏差(RSD)(n=3)均不大于5. 59%, 其中RSD ﹤ 5%的17种化合物占鉴定组分89. 5%。SSDE法和HD法挥发油平均收率分别为7. 30%(RSD=2. 37%(n=5))和6. 67%(RSD = 5. 26%(n=5))。SSDE法简便、快速, 适用于八角茴香挥发油的提取。
语种：
中文
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Simultaneous separation and purification of calycosin and formononetin from crude extract of Astragalus membranaceus Bge. var. mongholicus (Bge.) using high-speed counter-current chromatography
作者：
Li, Xia* ;Dong, Xinrong;Shuai, Ming;Liang, Yizeng
期刊：
Journal of Analytical Chemistry ,2015年70(1):92-97 ISSN：1061-9348
通讯作者：
Li, Xia
作者机构：
[Dong, Xinrong; Li, Xia; Shuai, Ming] Hunan Agr Univ Changsha, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Dong, Xinrong; Liang, Yizeng] Cent S Univ, Res Ctr Modernizat Chinese Med, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Li, Xia] H;Hunan Agr Univ Changsha, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
caycosin;formononetin;Astragalus membranaceus;counter-current;chromatography
摘要：
A simple and effective high-speed counter-current chromatography (HSCCC) method for simultaneous separation and purification of calycosin and formononetin from the ethanolic crude extract of Astragalus membranaceus is described. HSCCC separation was performed using a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (2.5: 2.5: 2: 3, v/v). A total of 7.5 mg calycosin and 11.2 mg formononetin was obtained from 500 mg crude extract of Astragalus membranaceus with purities of 98.5 and 98.3%, respectively, determined using HPLC. Chemical structures were confirmed by MS,<sup>1</sup>HNMR. ©2015, Pleiades Publishing, Ltd.
语种：
英文
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超声波法提取野生石蒜中加兰他敏
作者：
文祝友;熊海蓉;熊远福;李霞;蒋利华;...
期刊：
中国野生植物资源 ,2014年33(1):32-35 ISSN：1006-9690
作者机构：
湖南农业大学动物科技学院,长沙,4101281;湖南农业大学分析测试中心,长沙,410128;湖南农业大学理学院,长沙,410128;[赵明明; 熊海蓉; 文祝友; 熊远福; 蒋利华; 李霞] 湖南农业大学
关键词：
石蒜;加兰他敏;提取;超声波法;常规溶剂法
摘要：
石蒜是我国丰富的野生资源之一,其鳞茎富含重要药用成分加兰他敏。为了获得石蒜中加兰他敏的超声波提取方法,以野生石蒜为原料,用乙醇作提取剂,探讨了超声波提取加兰他敏的工艺条件,并与常规溶剂法进行了比较。分析了料液比、超声波功率、提取温度、提取时间、提取次数等因素对加兰他敏提取效果的影响,运用正交实验L9（34）确定了最佳提取工艺条件。结果显示,超声波提取加兰他敏的最佳工艺条件为:料液比1:6,超声波功率250 W,提取温度60℃,提取时间1.5 h,提取2次;加兰他敏的提取率为94.6%,产率为0.0543%;提取物中加兰他敏含量为15.53%。与常规溶剂法相比,超声波法具有用时少、提取率高、提取次数少等优点,整体效果优于常规溶剂法。
语种：
中文
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超微粉型油菜种衣剂的筛选及理化性能研究
作者：
熊海蓉;张先文;李霞;熊远福;文祝友;...
期刊：
农学学报 ,2014年4(7):19-23 ISSN：2095-4050
作者机构：
湖南农业大学分析测试中心,长沙,410128;湖南农业大学生物科学技术学院,长沙,410128;湖南农业大学理学院,长沙,410128;湖南农业大学动物科技学院,长沙,410128;[熊海蓉; 文祝友; 熊远福; 王宇婷; 张先文; 李霞] 湖南农业大学
关键词：
种子包衣;超微粉型种衣剂;油菜;配方筛选;理化性质;苗素质
摘要：
为了筛选超微粉型油菜种衣剂的合适配方,探明其理化性质,为新型油菜种衣剂的创制与应用提供参考,用3个自研超微粉型油菜种衣剂包衣油菜种子,通过发芽试验与理化检测,研究了超微粉型油菜种衣剂合适的配方、药种比及其理化性能,并与进口种衣剂进行了比较.结果表明：在自研超微粉型油菜种衣剂WFZ-5、WFY-1和WFW-6中WFY-1为最佳配方,其最佳药种比为1∶300; WFY-1的pH6.89,粘度为12.3 mPa/s,成膜时间7.8 min,包衣均匀度为95.5％,包衣脱落率为3.1％.WFY-1理化性能良好,能促进油菜生长,提高成苗率和苗素质,其综合效果优于进口种衣剂SLS.
语种：
中文
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Stage extraction of capsaicinoids and red pigments from fresh red pepper (Capsicum) fruits with ethanol as solvent
作者：
Dong, Xinrong* ;Li, Xia;Ding, Lei;Cui, Fuzhi;Tang, Zuojiao;...
期刊：
LWT ,2014年59(1):396-402 ISSN：0023-6438
通讯作者：
Dong, Xinrong
作者机构：
[Dong, Xinrong; Cui, Fuzhi; Tang, Zuojiao; Ding, Lei; Li, Xia] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Liu, Zhonghua; Dong, Xinrong] Hunan Agr Univ, Natl Res Ctr, Engn Technol Funct Ingredients Bot, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Dong, Xinrong] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Stage extraction;Capsaicinoids;Red pigments;Carotenoids;Fresh red pepper (Capsicum)
摘要：
A method for stage extraction of capsaicinoids and red pigments from fresh red peppers (FRPs) was developed in this work. Firstly, capsaicinoids were extracted from FRPs without any drying process by 40%-50% ethanol. Then red colorants without piquancy were extracted from the residues after removal of capsaicinoids using 95% ethanol as solvent with the conditions of 90°C of temperature of water bath, 4mL/g of ratio of solvent to material and 120min of extraction time. The yield of red pigments were 89.8% of total content of red colorants in FRPs, which is about 2.2 times that of dry red peppers (DRPs) dried from equivalent FRPs. Compared with conventional methods, the new processes were simple, but gave a high yield of red pigments without remain of toxic solvent. © 2014 Elsevier Ltd.
语种：
英文
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辣椒素对茶油的抗氧化与清除超氧阴离子自由基活性研究
作者：
李宇;刘宇光;李霞;董新荣
期刊：
中国酿造 ,2014年33(9):86-88 ISSN：0254-5071
作者机构：
湖南农业大学理学院,湖南长沙,410128;[董新荣; 刘宇光; 李宇; 李霞] 湖南农业大学
关键词：
辣椒素;茶油;抗氧化活性;超氧阴离子自由基;邻苯三酚法
摘要：
研究了辣椒素对高温强化处理的油茶籽油的抗氧化性能及对O2-·的清除能力。添加抗氧化剂的油茶籽油在（60±2）℃恒温下强化处理后,用碘量法来测定过氧化值（POV）评判抗氧化性能。通过改良邻苯三酚自氧化法测定辣椒素清除自由基能力。样品经10 d的60℃加热处理后,未添加抗氧化剂的POV值达到32.16 mmol/kg,添加质量分数0.10%辣椒素的POV值为17.03 mmol/kg。在相同浓度下,辣椒素的对油茶籽油的抗氧化效果介于同BHT与VE之间。当辣椒素的物质的量浓度为0.006 0 mmol/m L时,对O2-·自由基的清除率达到80.75%,此时维生素E为81.12%而BHT为77.15%。辣椒素具有较强的清除O2-·自由基的能力。
语种：
中文
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火棘果胶微波法提取及品质研究
作者：
熊海蓉;李霞;文祝友;熊远福;王锦;...
期刊：
中国农学通报 ,2014年30(3):271-275 ISSN：1000-6850
作者机构：
[熊海蓉] 湖南农业大学分析测试中心;[李霞; 熊远福; 王锦; 刘俊] 湖南农业大学理学院;[文祝友] 湖南农业大学动物科技学院
关键词：
火棘;果胶;提取;微波法;酸水解法;品质检验
摘要：
以火棘果为原料，用已获得的色素提取方法将火棘果中的红色素、黄色素提尽，然后用稀盐酸溶液作提取剂，运用微波法提取火棘果渣中的果胶，并检测果胶的品质。探讨提取剂pH、料液比、微波功率、时间、提取次数等因素对火棘果胶提取效果的影响，通过L_9(3~4)正交实验确定最佳工艺条件。结果表明，微波法提取火棘果胶的最佳条件为：提取剂pH 2，料液比1:9，微波功率300W，提取时间2.5min，提取2次；火棘果胶的提取率为86.7%，产率为7.55%。微波法提取火棘果胶耗时少、提取率高，优于传统酸水解法。检测表明，果胶品质符合标准QB 2484-2000，且有益元素含量丰富。
语种：
中文
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Assessment of nomadic rice-duck complex ecosystem on energy and economy
作者：
Huabin Zheng;Huang Huang;Diqin Li;Xumeng Li;Zhiqiang Fu;...
期刊：
生态过程 ,2014年3(1):1-8 ISSN：2192-1709
通讯作者：
Huang, Huang
作者机构：
[Li D.] College of Agronomy, Hunan Agricultural University, Changsha, 410128, China;Observation Station of Crop Cultivation in Central China, Ministry of Agriculture, Changsha, 410128, China;[Li X.] College of Science, Hunan Agricultural University, Changsha, 410128, China;[Chen C.; Zheng H.; Huang Huang; Fu Z.] College of Agronomy, Hunan Agricultural University, Changsha, 410128, China, Observation Station of Crop Cultivation in Central China, Ministry of Agriculture, Changsha, 410128, China
通讯机构：
[Huang Huang; Diqin Li] C;College of Agronomy, Hunan Agricultural University, Changsha, China<&wdkj&>Observation Station of Crop Cultivation in Central China, Ministry of Agriculture, Changsha, China<&wdkj&>College of Agronomy, Hunan Agricultural University, Changsha, China
关键词：
Economy;Energy;Intermediate-type technology;PSI;Traditional farming technology in China
摘要：
<jats:title>Abstract</jats:title>
<jats:sec>
<jats:title>Introduction</jats:title>
<jats:p>Modern intensive rice production has brought a large amount of environmental pollution and do not guarantee the safety of rice quality. Thus, to improve the farmer's rice production model to reduce agro-chemicals is of great importance to decrease pollution and to guarantee the security of food quality. Here, our experiments illustrated that nomadic rice-duck complex ecosystem (RD) could reduce energy input and increase both energy output and the values of the product safety index based on energy (PSI).</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Results</jats:title>
<jats:p>According to the results of our experiments, RD and rice monoculture production system (RM) were -0.6 and -0.78, respectively, which indicated that the safety potential of products in RD was higher than that of RM. Protein yield based on RD was significantly higher than that of RM. The output/input, gross income, and net income of RD were 15.26%, 39.51%, and 44.80%, respectively, higher than that of RM; the data suggest that the economic benefits of RD were greater than that of RM.</jats:p>
</jats:sec>
<jats:sec>
<jats:title>Conclusions</jats:title>
<jats:p>Consequently, as an intermediate-type technology, RD could become a feasible alternative that could reduce agro-chemical application rate without decreasing rice yield and increasing labor intensity. Furthermore, as an inheritance and development of the Chinese farming culture, RD is a classic Chinese farming technology withstanding more than 700 years of tests.</jats:p>
</jats:sec>
语种：
英文
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应用化学专业“三维一体”自主实践教学体系研究与实践——以湖南农业大学为例
作者：
李霞;董新荣;张薇;李宇;文志勇
期刊：
科技创新导报 ,2014年(25):146-147 ISSN：1674-098X
作者机构：
湖南农业大学理学院 湖南长沙 410128;[张薇; 董新荣; 志勇; 李宇; 李霞] 湖南农业大学
关键词：
应用化学专业;三维一体;自主实践教学体系
摘要：
在分析应用化学专业实践教学发展过程及现状的前提下,针对应用化学专业特点,湖南农业大学应用化学专业提出了以课内实践教学为主渠道,校内实践第二课堂和社会实践为两翼的＂三维一体＂自主实践教育体系。通过多年实践,完善了该实践教育体系,学生在动手能力和创新性培养上取得了良好的效果。
语种：
中文
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