Tunable dual emission of Ca3Al4ZnO10:Bi3+,Mn(4+)via energy transfer for indoor plant growth lighting
作者：
Zhou, Zhi;Zhong, Yuan;Xia, Mao;Zhou, Nan;Lei, Bingfu;...
期刊：
Journal of Materials Chemistry C ,2018年6(33):8914-8922 ISSN：2050-7526
通讯作者：
Wu, Fangfang;Wang, Jing
作者机构：
[Zhong, Yuan; Wu, Fangfang; Zhou, Zhi; Zhou, Nan] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Xia, Mao] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.;[Lei, Bingfu] South China Agr Univ, Dept Mat Sci & Engn, Guangzhou 510642, Guangdong, Peoples R China.;[Wang, Jing] Sun Yat Sen Univ, Sch Mat Sci & Engn, Sch Chem, Guangzhou 510275, Guangdong, Peoples R China.
通讯机构：
[Wu, Fangfang] H;[Wang, Jing] S;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Sun Yat Sen Univ, Sch Mat Sci & Engn, Sch Chem, Guangzhou 510275, Guangdong, Peoples R China.
摘要：
We synthesized a series of Bi3+ doped and Bi3+ and Mn4+ co-doped Ca3Al4ZnO10 (CAZO) phosphors via a conventional high-temperature solid-state reaction (SSR). Upon excitation at 330 nm, CAZO:Bi3+ shows blue-violet emission with a peak located at 405 nm. Under the same excitation source, Bi3+ and Mn4+ co-doped CAZO phosphors show dual emission, where the blue-violet emission is mainly from the 3P1 → 1S0 transition of Bi3+ and the far red emission is attributed to the 2E → 4A2 transition of Mn4+. The intrinsic great overlap between the emission band of Bi3+ and the excitation band of Mn4+ indicates the occurrence of energy transfers from Bi3+ to Mn4+. Fluorescence decays and photoluminescence spectra were measured to investigate the energy transfer process. The energy transfer efficiencies were also calculated. The relative emission intensities of Bi3+ and Mn4+ can be easily controlled by adjusting the concentrations of raw materials. It is demonstrated that the emission of CAZO:Bi3+,Mn4+ matches well with the absorption of four dominating pigments in plants, implying that the as-prepared phosphors are suitable to be applied in agricultural fields. © 2018 The Royal Society of Chemistry.
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英文
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Effect of pyrolysis condition on the adsorption mechanism of lead, cadmium and copper on tobacco stem biochar
作者：
Zhou, Zhi;Xu, Zhihui;Feng, Qiuju;Yao, Denghui;Yu, Jingang;...
期刊：
Journal of Cleaner Production ,2018年187:996-1005 ISSN：0959-6526
通讯作者：
Zhou, Nan;Zhong, Mei-e
作者机构：
[Zhou, Nan; Zhong, ME; Zhong, Mei-e; Zhou, Zhi; Xu, Zhihui; Yao, Denghui] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Feng, Qiuju] Jishou Univ, Coll Chem & Chem Engn, Jishou 416000, Peoples R China.;[Yu, Jingang] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Liu, Yifei; Wang, Desheng; Lv, Shuangqing] Tarim Univ, Coll Plant Sci, Alar Xinjiang 843300, Peoples R China.
通讯机构：
[Zhou, N; Zhong, ME] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Adsorption mechanism;Biochar;Heavy metals;Pyrolysis;Tobacco stem
摘要：
To promote the application of biochar in environmental pollution decontamination especially the heavy metals amendment, the relationship between the adsorption mechanism and biochar pyrolysis conditions was investigated. Tobacco stem was pyrolyzed at 300-700 degrees C for various residence time of 2 h, 4 h and 6 h. The adsorption of lead, cadmium and copper in single solute was then analyzed for as-obtained biochars. The change of the crystal structures, the related functional groups, and the exchanged cations were determined to reveal the effect of pyrolysis conditions on the adsorption mechanisms of these three heavy metals. The change of crystal structure confirmed that precipitation was the main mechanism of lead adsorption and that the tobacco stem biochar obtained at 700 degrees C for around 2 h was excellent adsorbent for lead clearance, since high temperature pyrolysis could promote the formation of carbonates but they would be decomposed under long-time exposure. The alteration of surface functional groups and exchanged cations of both original and demineralized biochars followed an affinity order of Cu(II)>Cd(II)>Pb(II) to oxygen functional groups. The surface complexation should be the primary mechanism of copper adsorption. Thus, the tobacco stem biochars pyrolyzed at 400 degrees C for 4 h could be effective adsorbents for copper amendment. Despite of the important role of precipitation in its removal, cadmium favores the cation-Is interaction best, and the biochars derived from tobacco stem at 700 degrees C for the residence time of 4-6 h are good adsorbents for cadmium decontamination. (C) 2018 Elsevier Ltd. All rights reserved.
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英文
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研讨模式教学与本科毕业设计之紧密关联
作者：
周南;武芳芳;钟美娥
期刊：
科技创新导报 ,2018年15(14):228-229 ISSN：1674-098X
作者机构：
湖南农业大学理学院化学系 湖南长沙 410128;[钟美娥; 武芳芳; 周南] 湖南农业大学
关键词：
研讨模式;本科毕业设计;教学改革;本科生教育;教学方法
摘要：
针对本科毕业设计中学生完成质量不高、教师指导不力等种种问题,笔者将研讨教学模式与本科毕业设计进行有机结合,以湖南农业大学理学院材料化学专业本科二年级同学为实践对象,组织同学们以本科毕业设计为主题,开展研讨模式教学以及本科毕业设计开题与答辩环节的模拟实践。通过这次实践,发现两者在很多层面有共通之处,且通过设计性的有机结合,可以达到两者互帮互助,相互促进的目的。这次实践发现,研讨教学模式与本科毕业设计之间具有紧密的联系,两者有机结合可以有效提升同学们的学习兴趣和自主能动性,对于本科毕业设计的高质量完成以及《文献检索》课程的高效率学习,均具有良好的促进作用。
语种：
中文
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混合式教学在农业院校材料化学中的应用
作者：
钟美娥;周南;王锦
期刊：
化工时刊 ,2018年32(3):48-49 ISSN：1002-154X
作者机构：
湖南农业大学理学院应用化学系,湖南 长沙,410128;[钟美娥; 周南; 王锦] 湖南农业大学
关键词：
混合式教学;必修课;材料化学;应用
摘要：
课程信息量大,专业性强是影响本科院校专业必修课程教学质量的关键原因。以《材料化学》为例,提出了基于网络平台的混合教学模式,利用互动性强的网络平台多角度传授专业知识,通过学生课前自主学习、教师课堂集中讲授和课后习题测试,并结合相关的管理监督机制,确保教学改革的顺利实施,有利于解决教学课时不足、学生知识面狭窄和学习主观能动性差等问题,有效提高教学质量。
语种：
中文
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Improved luminescence and energy-transfer properties of Ca14Al10Zn6O35:Ti4+,Mn4+ deep-red-emitting phosphors with high brightness for light-emitting diode (LED) plant-growth lighting
作者：
Zhou, Zhi;Li, Yiran;Xia, Mao* ;Zhong, Yuan;Zhou, Nan* ;...
期刊：
DALTON TRANSACTIONS ,2018年47(38):13713-13721 ISSN：1477-9226
通讯作者：
Xia, Mao;Zhou, Nan
作者机构：
[Xia, Mao; Zhong, Yuan; Xia, M; Zhou, Nan; Zhou, Zhi; Li, Yiran] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Xia, Mao] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.;[Hintzen, H. T. (Bert)] Delft Univ Technol, Fac Appl Sci, Sect Fundamental Aspetts Mat & Energy, Grp Luminescent Mat, Delft, Netherlands.
通讯机构：
[Xia, M; Zhou, N] H;[Xia, Mao] C;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
摘要：
For plant-growth lighting, novel deep-red emission phosphors with high brightness were obtained by co-doping Ti4+ and Mn4+ into a Ca14Al10Zn6O35 substrate through a conventional solid-state reaction strategy. The nominal Ca14-(x+y)/2Al10-x-yZn6O35:xTi4+,yMn4+ (CAZO:Ti4+,Mn4+) phosphors could be excited by both near-ultraviolet (NUV) and blue-light-emitting diode (LED) chips efficiently and exhibited a strong deep-red emission band ranging from 650 nm to 750 nm, which should be the result of the 2E → 4A2 transition inside the [MnO6]8- octahedral. Multiple energy transfer from Ti4+ to Mn4+ was detected in this CAZO; whereby Ti4+ and Mn4+ phosphors were verified to be a result of the dipole-dipole interaction under excitation at 270 nm. LED plant-growth lights were fabricated using the as-prepared nominal Ca13.825Al9.65Zn6O35:0.15Mn4+,0.2Ti4+,0.005H3BO3 (CAZO:Mn4+,Ti4+,H3BO3) phosphors pumped by a 460 nm blue-chip; this luminaire could be used to greatly promote the cultivation of succulent plants. Combined with the attractive thermal stability as well as high quantum efficiency (QE) of this phosphor, it was demonstrated that these novel phosphors may be candidate deep-red luminescent materials for LED plant lighting. © 2018 The Royal Society of Chemistry.
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英文
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The Improvement of SiO2 Nanoparticles on the Oxygen Reduction Reaction Property of Nitrogen-Doped Mesoporous Graphene Spheres Prepared by Spray Drying
作者：
Xiao, Pengyu;Wang, Kaibin;Chen, Zhi;Zhou, Nan;Wang, Taihong;...
期刊：
Nanoscience and Nanotechnology Letters ,2018年10(2):200-206 ISSN：1941-4900
通讯作者：
Zhang, Ming
作者机构：
[Xiao, Pengyu; Wang, Kaibin; Wang, Taihong] Hunan Univ, Sch Chem & Chem Engn, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Chen, Zhi; Zhang, Ming] Hunan Univ, Sch Phys & Elect, Key Lab Micronano Optoelect Devices, Minist Educ, Changsha 410082, Hunan, Peoples R China.;[Zhou, Nan] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Zhang, Ming] H;Hunan Univ, Sch Phys & Elect, Key Lab Micronano Optoelect Devices, Minist Educ, Changsha 410082, Hunan, Peoples R China.
关键词：
Spray Drying;Nitrogen-Doped Graphene;SiO2;Oxygen Reduction Reaction
摘要：
The catalysts for oxygen reduction reaction (ORR) have been the research hot-pot of electrochemical energy, especially the graphene-based non-precious metal catalysts. Generally, the properties of graphene for ORR are affected by their specific surface areas, doping atoms, morphology, and so on. In this study, nitrogen-doped mesoporous graphene spheres (NGS) have been synthesized through a simple and efficient spray drying approach. It was discovered that SiO2 played a key role in the ORR catalytic property of NGS. The addition of SiO2 could promote the formation of spherical structure of graphene oxide, so that the material could wrap the nitrogen source in and reduce the nitrogen loss in the process of heat treatment, which would increase the nitrogen content. Simultaneously, the mesoporous structure with high specific surface area can be obtained by removing SiO2 with HF, which can increase the contact area between catalyst and reactant, improve the efficiency of mass transfer, and further improve the ORR catalytic performance of NGS. Compared with commercial Pt/C, NGS demonstrates higher electrocatalytic activity and exhibits good durability.
语种：
英文
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Enhancing the electrochemical properties of LiTi2 (PO4 )3 /C anode for aqueous rechargeable lithium battery by Li vacancy
作者：
Zhou, Zhi;Li, Yiran;Xia, Mao* ;Zhou, Nan
期刊：
Solid State Ionics ,2018年315:1-6 ISSN：0167-2738
通讯作者：
Xia, Mao
作者机构：
[Xia, Mao; Zhou, Zhi; Zhou, Nan; Li, Yiran] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Xia, Mao] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Xia, Mao] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Aqueous rechargeable lithium battery;Electrochemical kinetics;Energy storage;Li vacancy;LiTi 2 (PO 4 ) 3 /C composite
摘要：
In this paper, Li<inf>1–x</inf>Ti<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C composites (x = 0, 0.03, 0.05, 0.07) were synthesized by sol-gel approach, and the influence of Li vacancy on electrochemical performance of LiTi<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C anode for aqueous rechargeable lithium battery was studied. Li vacancy hardly influences the crystal structure and morphology of the composite. Electrochemical measurement results demonstrated that Li<inf>1–x</inf>Ti<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C exhibited better performance compared with pristine LiTi<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C, and Li<inf>0.95</inf>Ti<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C has the best properties. Li<inf>0.95</inf>Ti<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C delivered the discharge capacity of 104.3, 92.6, and 71.8 mAh g<sup>−1</sup>at 0.2, 5, and 20 C (1 C = 150 mA g<sup>−1</sup>), 4.1, 27.3, and 34.4 mAh g<sup>−1</sup>larger than that of Li<inf>0.95</inf>Ti<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C at corresponding rates, respectively. After 1000 cycles at 5 C, the discharge capacity retention for Li<inf>0.95</inf>Ti<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C can reach 75.3%, 15.4% larger than that for LiTi<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>/C. Our study reveals that Li vacancy is an efficient method to enhance the electrochemical properties of LiTi<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>-based materials.<br/> ©2017
语种：
英文
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pH dependent hydrothermal synthesis of Ca14Al10Zn6O35:0.15Mn4+ phosphor with enhanced photoluminescence performance and high thermal resistance for indoor plant growth lighting
作者：
Zhou, Zhi;Wang, Bianbian;Zhong, Yuan;Zhang, Wei;Zhang, Ye;...
期刊：
Ceramics International ,2018年44(16):19779-19786 ISSN：0272-8842
通讯作者：
Zhou, Nan
作者机构：
[Wang, Bianbian; Zhang, Wei; Zhang, Ye; Zhong, Yuan; Zhou, Zhi; Gao, Peixing; Zhou, Nan] Hunan Agr Univ, Coll Sci, 1 Nongda Rd, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Zhou, Nan] H;Hunan Agr Univ, Coll Sci, 1 Nongda Rd, Changsha 410128, Hunan, Peoples R China.
关键词：
Ca 14 Al 10 Zn 6 O 35 :Mn 4+;Hydrothermal method;Luminescence properties;Plant growth lighting
摘要：
Artificial light source for indoor cultivation has been vastly impeded by the lack of high far red emitting phosphors. Recently, Mn<sup>4+</sup> activated phosphors were reported to be promising luminescent materials to solve above matter. In this study, controllable design of Ca<inf>14</inf>Al<inf>10</inf>Zn<inf>6</inf>O<inf>35</inf>:0.15Mn<sup>4+</sup> (CAZO:0.15Mn<sup>4+</sup>) far red emitting phosphors was realized via pH assisted hydrothermal approach. The pure CAZO:0.15Mn<sup>4+</sup> phosphors were obtained merely when the reaction pH was 1 or 2. Meanwhile, by adjusting the pH value of the reaction solution, far red emission CAZO:0.15Mn<sup>4+</sup> phosphors with grains, sphere-like as well as aggregated bulk particles can be achieved at pH = 4, pH = 6 and pH = 10, respectively. Furthermore, the structures and morphologies depended photoluminescence (PL) performances of CAZO:0.15Mn<sup>4+</sup> were checked. The best PL performance was found for the phosphor produced at pH = 6, while over acidic or alkaline conditions would lower the emission intensity. In addition, this phosphor also exhibit good thermal resistance which can maintain 78% initial intensity at 150 °C. The practical indoor tobacco cultivation demonstrated that CAZO:0.15Mn<sup>4+</sup> obtained through this pH adjusted hydrothermal route is a promising phosphor for indoor plant growth lighting.<br/> ©2018 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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Self-assembly between photoresponsive azobenzene-based dications and thermally sensitive PNIPAM-b-PAA block copolymers in aqueous solution
作者：
Peng, Chang;Zhao, Wenkui;Wu, Anjun* ;Zhou, Nan* ;Chen, Shu*
期刊：
Journal of Polymer Research ,2018年25(3):1-8 ISSN：1022-9760
通讯作者：
Wu, Anjun;Zhou, Nan;Chen, Shu
作者机构：
[Peng, Chang; Wu, Anjun; Zhou, Nan; Zhao, Wenkui] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Chen, Shu] Hunan Univ, Sch Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Wu, AJ; Zhou, N; Chen, Shu] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Hunan Univ, Sch Chem & Chem Engn, Changsha 410082, Hunan, Peoples R China.
关键词：
Azobenzene;Block copolymers;Self-assembly;Photoresponse
摘要：
The effect of the photoresponsive azobenzene-based dications (AzoC<inf>10</inf>N<inf>2</inf>O<inf>2</inf><sup>2+</sup>) on the association in thermally sensitive poly(N-isopropylacrylamide)-b-poly(acrylic acid) (PNIPAM-b-PAA) solutions is studied for the first time. The self-assembly of this complexes was measured by dynamic light scattering (DLS), scanning electron microscopy (SEM) and ultraviolet-visible (UV-Vis) spectrum. Results show that the micellar size of this colloidal complexes can be changed by the molar weight of AzoC<inf>10</inf>N<inf>2</inf>O<inf>2</inf><sup>2+</sup>and reversibly controlled by ultraviolet (UV) light (365 nm) and blue light (455 nm) irradiation. It is the first to use azobenzene-based dications to control the self-assembly of PNIPAM-b-PAA by light irradiation, which enables the selection of appropriate conditions for the micellar properties by light.<br/> ©2018, Springer Science+Business Media B.V., part of Springer Nature.
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英文
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引导本科生深入实验研究的几点探讨
作者：
周智;黄升雄;吴安军;周南
期刊：
科技创新导报 ,2018年15(24):249-250 ISSN：1674-098X
作者机构：
湖南农业大学 理学院 湖南长沙 410128;[周南; 周智; 吴安军; 黄升雄] 湖南农业大学
关键词：
化学专业;本科生;实验研究
摘要：
深入实验研究,以研究促学习是实践类自然科学专业本科生的重要学习方式,从本科阶段培养学生的思维能力和动手能力,对于提高学生的科研能力,引导学生进入科研状态至关重要.本文基于作者在本科教学和指导本科生实验研究方面的探讨,从课堂学习支撑实验研究,以前沿研究促进基础学习,以多场景教学和思维能力培养本科生科研实验能力,以硕、博士研究生带动本科生开展前沿学术研究等方面做了具体分析.总而言之,引导本科生深入实验研究,对促进本科生的逻辑思维能力,锻炼本科生的专业技能,吸引优秀的硕士生源,具有重要意义.
语种：
中文
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Accelerated polysulfide redox kinetics revealed by ternary sandwich-type S@Co/N-doped carbon nanosheet for high-performance lithium-sulfur batteries
作者：
Zhong, Mei-e;Guan, Jindiao;Feng, Qiuju;Wu, Xiongwei;Xiao, Zhubing;...
期刊：
Carbon ,2018年128:86-96 ISSN：0008-6223
通讯作者：
Zhou, Nan;Gong, Daoxin
作者机构：
[Tong, Shuai; Zhong, Mei-e; Wu, Xiongwei; Zhang, Wei; Zhou, Nan; Guan, Jindiao] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Feng, Qiuju] Jishou Univ, Coll Chem & Chem Engn, Jishou 416000, Peoples R China.;[Xiao, Zhubing] Chinese Acad Sci, Fujian Inst Res Struct Matter, State Key Lab Struct Chem, Fuzhou 350002, Fujian, Peoples R China.;[Gong, Daoxin] Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Zhou, Nan; Gong, Daoxin] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.
摘要：
Lithium-sulfur (Li-S) batteries show significant advantages for next-generation energy storage systems due to the high theoretical energy density and cost effectiveness. The main challenge for developing long-life and high-performance Li-S batteries is to simultaneously restrain the shuttle of soluble polysulfides while accelerating the redox kinetics of sulfur-related species during cell operation. Herein, a sandwich-type sulfur@Co/N-doped carbon (S@Co-NC) ternary composite is synthesized, combining in a simple way the advantages of synergetic physical and chemical confinement on sulfur-related species. A further electrochemical redox kinetic study confirms that the incorporated conductive Co mediators and doped N species serve as dual electrocatalysts, substantially accelerating the kinetics of the polysulfide redox reactions. By relieving the sluggishness of polysulfide redox reactions, the as-obtained sandwich-type S@Co-NC composite has significantly promoted electrochemical performance including enhanced rate capability, lower polarization and higher Coulombic efficiency. It delivers extremely high discharge capacity of 1401 mAh g<sup>−1</sup>at 0.05 C with an area sulfur loading of 1.3 mg cm<sup>−2</sup>. More importantly, the ternary electrode retains a high rate capability of 694 mAh g<sup>−1</sup>over extensive 600 cycles at 1 C, with nearly 100% Coulombic efficiency maintenance. These results suggest that the S@Co-NC ternary composite provides possibility of realizing the industrially practical Li-S batteries.<br/> ©2017 Elsevier Ltd
语种：
英文
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LiTi2(PO4)3@carbon/graphene hybrid as superior anode materials for aqueous lithium ion batteries
作者：
Zhou, Zhi* ;Luo, Wei;Huang, Hao;Huang, Shengxiong;Xia, Yongji;...
期刊：
Ceramics International ,2017年43(1):99-105 ISSN：0272-8842
通讯作者：
Zhou, Zhi;Zhou, Nan
作者机构：
[Zhou, Zhi; Zhou, Nan; Xia, Yongji; Huang, Shengxiong; Luo, Wei; Huang, Hao] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[He, Zhangxing] North China Univ Sci & Technol, Sch Chem Engn, Tangshan 063009, Peoples R China.
通讯机构：
[Zhou, Z; Zhou, N] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Anode;Aqueous lithium ion batteries;Graphene;Hybrid;LiTi 2 (PO 4 ) 3
摘要：
In this paper, LiTi<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>@carbon/graphene (LCG) hybrid was prepared and investigated as anode for aqueous lithium ion batteries (ALIBs). The as-prepared hybrid was characterized by XRD, SEM, TEM and TGA. The electrochemical performances of nano-structured materials as anode were evaluated by cyclic voltammetry, electrochemical impedance spectroscopy and charge-discharge tests. The cell using LCG as anode exhibits excellent cycling performance both at relatively low and high rates. The capacity retention of LCG can remain 87.6% at 0.2 C after 200 cycles and 77.2% at 5 C after 1000 cycles compared with LiTi<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>@carbon (0.2 C: 71.8%, 5 C: 58.1%). Moreover, LCG reveals superior rate capability with 80.8 mA h g<sup>−1</sup>, 62.1 mA h g<sup>−1</sup>at 10 C and 20 C, respectively. The outstanding electrochemical performance of LCG comes from the improved electrical conductivity and the forming of efficient conductive network. The results demonstrate that the graphene-modified LiTi<inf>2</inf>(PO<inf>4</inf>)<inf>3</inf>@carbon is a promising anode for ALIBs. ©2016 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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农业院校定量分析实验的教学探索
作者：
李辉勇;周南;周军
期刊：
教育教学论坛 ,2017年(35):270-271 ISSN：1674-9324
作者机构：
湖南农业大学理学院,湖南 长沙,410128;[周南; 李辉勇; 周军] 湖南农业大学
关键词：
农业院校;定量分析实验;教学
摘要：
本文结合我校实验化学教学改革的情况,重点阐述了高等农业院校定量分析实验教学内容的选择,"量"与"误差"的概念在定量分析基本单元操作及实验过程中的重要性.采用过程考核与操作考核相结合的成绩评定模式,提高学生的综合素质,培养学生的创新意识与创新能力.
语种：
中文
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Dy3+ Mn4+ co-doped Ca14 Ga10-M Alm Zn6 O35 far-red emitting phosphors with high brightness and improved luminescence and energy transfer properties for plant growth LED lights
作者：
Zhou, Zhi;Xia, Mao;Zhong, Yuan;Gai, Shujie;Huang, Shengxiong;...
期刊：
Journal of Materials Chemistry C ,2017年5(32):8201-8210 ISSN：2050-7526
通讯作者：
Zhou, Nan
作者机构：
[Xia, Mao; Huang, Shengxiong; Zhong, Yuan; Gai, Shujie; Zhou, Zhi; Zhou, Nan] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Tian, Yun; Lu, Xiangyang; Zhou, Zhi; Zhou, Nan] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha 410128, Hunan, Peoples R China.;[Tian, Yun; Lu, Xiangyang; Zhou, Zhi; Zhou, Nan] Hunan Agr Univ, Hunan Prov Univ Key Lab Agr Biochem & Biotransfor, Changsha 410128, Hunan, Peoples R China.;[Xia, Mao] Cent S Univ, State Key Lab Powder Met, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Zhou, Nan] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, Hunan Prov Univ Key Lab Agr Biochem & Biotransfor, Changsha 410128, Hunan, Peoples R China.
摘要：
A novel substrate of Ca<inf>14</inf>Ga<inf>10-m</inf>Al<inf>m</inf>Zn<inf>6</inf>O<inf>35</inf>(CGAZO) was successfully synthesized via a high-temperature solid-state reaction method and co-doped with Dy<sup>3+</sup>and Mn<sup>4+</sup>to form a new deep red phosphor (CGAZO:Dy<sup>3+</sup>,Mn<sup>4+</sup>) for plant growth LED lighting. This extraordinary phosphor can exhibit strong far-red emission with a maximum peak at 715 nm between 650 and 750 nm, and other four shoulder peaks at 680, 689, 698 and 706 nm, which can be ascribed to 2E<inf>g</inf>→2A<inf>g</inf>spin-forbidden transition of Mn<sup>4+</sup>. X-ray diffraction (XRD) patterns clarified that Ga<sup>3+</sup>sites in the host were partly replaced by Al<sup>3+</sup>ions. Moreover, an effective energy transfer from Dy<sup>3+</sup>to Mn<sup>4+</sup>in the CGAZO host had been verified since linear reduction of emission intensities and decay times of the Dy<sup>3+</sup>emission of the phosphors CGAZO:Dy<sup>3+</sup>,Mn<sup>4+</sup>with increasing concentration of Mn<sup>4+</sup>was observed. Finally, a LED device was fabricated using a 460 nm blue-chip, silicon gel, and the as-obtained far-red emitting CGAZO:Dy<sup>3+</sup>,Mn<sup>4+</sup>phosphors. The results of the tobacco plant cultivation lighting by this LED device indicate that the as-prepared phosphor has a potential application in the agricultural industry. ©2017 The Royal Society of Chemistry.
语种：
英文
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材料化学专业英语教学方法改革探究
作者：
周南;周智
期刊：
科技创新导报 ,2017年(6):187-188 ISSN：1674-098X
作者机构：
湖南农业大学理学院化学与材料科学系 湖南长沙 410128;[周智; 周南] 湖南农业大学
关键词：
专业英语;教学方法;改革
摘要：
针对材料化学专业本科生的专业英语需求和《材料化学专业英语》的教学现状,该文从教学方法上对《材料化学专业英语》进行了研讨探究,根据专业英语教学的实用性将专业英语教学与学生的毕业设计和毕业答辩相结合,凸显专业英语在大学学习中的重要性.通过类比基础大学英语教学中词汇、段落和表达,引入专业英语的词汇记忆、段落翻译和语言表达方法,提高学生的学习兴趣和学习效率.
语种：
中文
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本科生创新论坛培养模式分析
作者：
周南;周智
期刊：
化工时刊 ,2017年31(5):43-45 ISSN：1002-154X
作者机构：
湖南农业大学理学院,湖南,410128;[周智; 周南] 湖南农业大学
关键词：
创新论坛;人才培养;本科生
摘要：
在市场经济深入发展、知识创新不断加速、社会竞争日趋激烈的当今,人才培养与社会发展要求不相适应的矛盾日益突出。人才的知识和能力要素结构正在发生重大变化,社会对人才的需求也必然从只强调“专才”到“复合型人才”和“交叉型人才”过渡。在当代,社会的快速发展既给教育提供了机会,也带来了巨大的挑战。社会不断发展进步,但我国高等教育模式却不适应社会经济的发展需要。本文主要通过对国内外创新论坛培养模式的分析,进一步说明大学生的创新精神和实践能力,是新世纪高等教育发展的需要,更是我国社会发展和国际竞争的需要。科学有效地开展大学生创新论坛培养模式,有利于提高高等教育人才的质量,有利于精神与物质财富的提高,有利于国民经济的发展。
语种：
中文
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Enhanced electrochemical properties of Bi nanowires as anode materials in lithium and sodium batteries
作者：
Zhou, Zhi;Huang, Shengxiong;Luo, Wei;Wang, Chang;Fan, Xin;...
期刊：
Current Nanoscience ,2017年13(4):342-348 ISSN：1573-4137
通讯作者：
Zhou, Nan;Fang, Dong
作者机构：
[Huang, Shengxiong; Luo, Wei; Zhou, Zhi; Zhou, Nan] Hunan Agr Univ, Coll Sci, Changsha, Hunan, Peoples R China.;[Fang, Dong; Wang, Chang; Wan, Renzhuo] Wuhan Text Univ, Coll Mat Sci & Engn, Minist Educ, Key Lab New Text Mat & Applicat Hubei Prov, Wuhan, Peoples R China.;[Fan, Xin] Guilin Univ Technol, Coll Mat Sci & Engn, Guangxi Minist Prov Jointly Constructed Cultivat, Guilin 541004, Peoples R China.;[Fang, Dong] Fac Wuhan Text Univ, Dept Mat Sci & Engn, Wuhan, Peoples R China.
通讯机构：
[Zhou, Nan] H;[Fang, Dong] F;Hunan Agr Univ, Coll Sci, Changsha, Hunan, Peoples R China.;Fac Wuhan Text Univ, Dept Mat Sci & Engn, Wuhan, Peoples R China.
关键词：
Bismuth nanowires;Bi/C nanocomposites;electrochemistry;Li-ion battery;Na-ion battery
摘要：
Background: Bismuth (Bi) has been studied due to its high theoretical gravimetric capacity of 385 mAh g−1, which is as important as gravimetric capacity for the practical application of battery systems in electronic mobile devices. However, there have been limited fundamental explorations on the electrochemical performances of Bi. Furthermore, the mechanism differences for the Bi anodes in lithium-ion batteries (LIBs) and sodium-ion batteries (NIBs) should be further investigated. Methods: The Bi nanowires were fabricated by vacuum melting and pressure injection method. Briefly, a Bi bulk was placed into an injection apparatus and heated up above 275 °C (melt point of Bi: 271.3 °C), and then the melt was injected into the AAO pores by a hydraulic force. After the injection process, the chamber was kept in vacuum to cool down slowly. Subsequently, the AAO template was dissolved away slowly in the etching solution (0.4 M H3PO4+ 0.2 M CrO3) at 60 °C for 72 h to expose Bi nanowires. Finally, after sonication dispersion, centrifugal sedimentation and rinsing with deionized water several times to remove the excess H3PO4-CrO3 mixture, the free-standing Bi nanowires were collected. Results: The morphologies of AAO, AAO/Bi and Bi nanowires were tested and presented in detail. It found that the Bi nanowires can be obtained by pressure injection method followed with dissolve the AAO template. After boll milling with C to form Bi/C nanocomposites, the nanocomposites were assembled as an electrode of LIBs or NIBs. It exhibited high capacities in LIBs, while for NIBs, the capacity retention was relatively low. Conclusion: Bi nanowires have been prepared by mechanical pressure injection method and thoroughly dissolution of the AAO template. After successive milling of Bi nanowires with carbon black, Bi/C nanocomposites are obtained. The Bi/C nanocomposites used as electrode in LIBs exhibit high capacities and the initial discharge/charge capacities of Bi/C anode are around 1223.4/571.9, 905.9/412.3, 829.2/ 362.6 mAh g-1 at current densities of 20, 200 and 500 mA g-1, respectively. The enhanced electrical performances are attributed to the smaller size of Bi nanowires and the introduced carbon black to buffer the volume changes during discharge/charge process. In NIBs, the capacity retention after 50 cycles reaches 284.7, 196.2 and 168.3 mAh g-1 at current densities of 20, 200 and 500 mA g-1, respectively. Furthermore, in LIBs, Bi and Li+ ions combine together through an alloying process, while in NIBs, only an intercalation process occurs for Bi and Na+ without indication of alloying.
语种：
英文
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Electrochemical presodiation promoting lithium storage performance of Mo-based anode materials
作者：
Li, Huiyong;Liu, Ping;Zhou, Nan;Huang, Xiaobing;Wang, Haiyan*
期刊：
Ceramics International ,2017年43(15):11967-11972 ISSN：0272-8842
通讯作者：
Wang, Haiyan
作者机构：
[Zhou, Nan; Li, Huiyong] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Wang, Haiyan; Liu, Ping] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Peoples R China.;[Huang, Xiaobing] Hunan Univ Arts & Sci, Coll Chem & Chem Engn, Changde 415000, Peoples R China.
通讯机构：
[Wang, Haiyan] C;Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Peoples R China.
关键词：
Electrochemical presodiation;Li ion batteries;MoO3;MoS2
摘要：
Stabilizing the layer structures of Mo-based anode materials is still a challenge for Li ion batteries. Herein, we proposed an electrochemical presodiation strategy for MoS<inf>2</inf>and MoO<inf>3</inf>to improve their cycling stability. It is interesting to note that the cycling stability of as-treated MoS<inf>2</inf>and MoO<inf>3</inf>was significantly improved. Although the reversible discharge capacity was slightly decreased, the capacity of the pretreated MoS<inf>2</inf>at 300 mA g<sup>−1</sup>was retained at 345 mA h g<sup>−1</sup>after 100 cycles while that of the pristine one decreased to 151 mA h g<sup>−1</sup>. The capacity of the pretreated MoO<inf>3</inf>after 60 cycles was also improved from 275 mA h g<sup>−1</sup>(the pristine one) to 460 mA h g<sup>−1</sup>. The stabilizing effect was further verified by scanning electron microscope (SEM) analysis. Electrochemical presodiation here could be a promising modification strategy for Mo-based anode materials. ©2017 Elsevier Ltd and Techna Group S.r.l.
语种：
英文
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Effect of phosphoric acid on the surface properties and Pb(II) adsorption mechanisms of hydrochars prepared from fresh bananapeels
作者：
Zhou, Nan;Chen, Honggang;Feng, Qiuju;Yao, Denghui;Chen, Huanli;...
期刊：
Journal of Cleaner Production ,2017年165:221-230 ISSN：0959-6526
通讯作者：
Zhou, Zhi;Li, Huiyong
作者机构：
[Chen, Honggang; Chen, Huanli; Zhou, Zhi; Li, Huiyong; Zhou, Nan; Yao, Denghui] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Feng, Qiuju] Jishou Univ, Coll Chem & Chem Engn, Jishou 416000, Peoples R China.;[Wang, Haiyan] Cent S Univ, Coll Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Tian, Yun; Lu, Xiangyang] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Zhou, Z; Li, HY] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Adsorption mechanism;Banana peel;Biochar;Heavy metals removal;Hydrochar;Hydrothermal carbonization
摘要：
The acidic environment has been confirmed to have significant influence on the biochar products through hydrothermal carbonization. To investigate the effect of H<inf>3</inf>PO<inf>4</inf>on the surface properties and adsorption mechanisms of the biochar, fresh banana peels were used as feedstock and transformed into hydrochars under the catalysis of H<inf>3</inf>PO<inf>4</inf>with concentration ranges from 0% to 50%wt. The addition of H<inf>3</inf>PO<inf>4</inf>greatly impacted the physicochemical properties of the as-obtained hydrochars, such as carbonization degrees, pH values, amount of surface acidic functional groups and then further affected the adsorption mechanisms of lead ions on those hydrochars. Hydrochars catalyzed by H<inf>3</inf>PO<inf>4</inf>with higher concentration showed higher degree of carbonization, lower value of pH and fewer amount of acidic functional groups, while lower content of H<inf>3</inf>PO<inf>4</inf>could not completely catalyze the degradation reactions and resulted in larger quantity of intermolecular locked oxygen containing groups that could not be participated into the adsorption process. Among all six samples, hydrochar generated in 30%wt H<inf>3</inf>PO<inf>4</inf>exhibited the best adsorption property of 241 mg g<sup>−1</sup>, possibly due to the largest concentration of the acidic functional groups on the surface rather than in the intermolecular structure of the carbon. It had been confirmed that the adsorption mechanisms were the combination of surface complexation, cationic exchange and part of precipitation. Hydrochars derived from fresh banana peel via hydrothermal carbonization catalyzed by phosphoric acid could be excellent adsorbents for lead removal in aqueous environments. ©2017 Elsevier Ltd
语种：
英文
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类比法在有机化学教学的应用初探
作者：
周南;周智
期刊：
化工时刊 ,2017年31(2):48-50 ISSN：1002-154X
作者机构：
湖南农业大学理学院化学与材料科学系,湖南长沙,410128;[周智; 周南] 湖南农业大学
关键词：
类比法;类比教育;有机化学
摘要：
化学反应机理是有机化学课程学习中很不易理解的重点和难点,学生们常常捉摸不透,非化学专业学生则更容易听得云里雾里。在亲核取代反应机理、消除反应机理等复杂机理的授课过程中采用类比法,对化学反应机理进行深入浅出的解释,发现同学们在这种方法下的理解记忆情况相比以前大大提升,系统推广之后发现能够提高学生的学习兴趣和积极性,效果显著,值得大范围推广。
语种：
中文
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