Insight into effect of CaCO3 on reduction roasting of fine-grained silicate type iron oxide ore and its application on Fe separation and recovery
作者：
Wu, Fangfang;Deng, Jie;Mi, Baobin;Xiao, Zhu;Kuang, Jiaqi;...
期刊：
Powder Technology ,2019年356:170-176 ISSN：0032-5910
通讯作者：
Yu, Peng;Liu, Biqiong
作者机构：
[Kuang, Jiaqi; Yu, Peng; Xiao, Zhu; Deng, Jie; Liu, Hui; Wu, Fangfang; Liang, Min] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Mi, Baobin] Hunan Acad Agr Sci, Res Inst Vegetables, Changsha 410125, Hunan, Peoples R China.;[Liu, Biqiong] Hunan Agr Univ, Grad Sch, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Yu, Peng; Liu, Biqiong] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Hunan Agr Univ, Grad Sch, Changsha 410128, Hunan, Peoples R China.
关键词：
Fined-grained iron ore;CaCO3;Alkali lignin;Microwave;Silicate gangue removal
摘要：
To solve the problem of processing of refractory iron oxide ore resulted from its fine-grained disseminated structure, in this paper, an improved technology was innovatively proposed, which consisted of three stages of reduction roasting-acid leaching followed by magnetic separation, and CaCO3 was introduced during roasting process. Mechanism analyses indicated that kaolinite, a major gangue in ore, can be thermally dehydrated to amorphous metakaolin during roasting process, and CaCO3 can in part react with metakaolin-converting the stable kaolinite gangue mineral into acid-soluble Ca3Al2(SiO4)(3), and subsequently Ca3Al2(SiO4)(3) was selectively removed by acid leaching process. Moreover, the presence of CaCO3 can also improve the gathering state of Fe-rich particles, which is beneficial for magnetic separation. Iron concentrate obtained via the proposed technology contained 53.73% Fe, 9.02% Mn, 7.51% Al, and 2.46% Si, with a Fe recovery ratio of 88.20%, which surely meet the iron ore quality requirement of steel and iron industry. (C) 2019 Published by Elsevier B.V.
语种：
英文
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Ultrasensitive graphene quantum dots-based catalytic hairpin assembly amplification resonance light scattering assay for p53 mutant DNA detection
作者：
Wang, Shuang;Zhang, Feng;Chen, Chunyan* ;Cai, Changqun*
期刊：
Sensors and Actuators B-Chemical ,2019年291:42-47 ISSN：0925-4005
通讯作者：
Chen, Chunyan;Cai, Changqun
作者机构：
[Chen, CY; Cai, CQ; Chen, Chunyan; Cai, Changqun; Wang, Shuang] Xiangtan Univ, Coll Chem, Key Lab Green Organ Synth & Applicat Hunan Prov, Key Lab Environm Friendly Chem & Applicat,Minist, Xiangtan 411105, Peoples R China.;[Zhang, Feng] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Chen, CY; Cai, CQ] X;Xiangtan Univ, Coll Chem, Key Lab Green Organ Synth & Applicat Hunan Prov, Key Lab Environm Friendly Chem & Applicat,Minist, Xiangtan 411105, Peoples R China.
关键词：
Amplification;Catalytic hairpin assembly;Enzyme-Free;Graphene quantum dots;Resonance light scattering
摘要：
In this work, a simple, enzyme-free and ultrasensitive resonance light scattering (RLS) method was developed based on graphene quantum dots (GQDs) with a catalytic hairpin assembly amplification strategy for selective detection of mutant DNA. This method contains two probes, GQDs-H1 and GQDs-H2. Two partially complementary hairpins (H1 and H2) are ingeniously and rationally designed, and they can't spontaneously hybridize with each other in the absence of target. When the target is added, the target binds with GQDs-H1 and forms GQDs-H1: target intermediates. Then, GQDs-H2 hybridizes with the GQDs-H1: target and frees the target, triggering another reaction cycle. A large amount of GQDs-H1:H2-GQDs aggregates are formed, which obviously increase the RLS signals. A limit of detection of 0.8 pmol L−1 and two linear ranges of 1.0 pmol L−1–1.5 nmol L−1 and 1.5–50.0 nmol L−1 for target detection are obtained. This detection method is simple, available, and low-cost. It can be potentially applied to other DNA detection and broadens the sensing application of GQDs for the detection of other significant disease-related markers. © 2019 Elsevier B.V.
语种：
英文
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Escape quartered theorem and the connectivity of the Julia sets of a family of rational maps
作者：
Wang, Youming* ;Yang, Fei;Zhang, Song;Liao, Liangwen
期刊：
DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS ,2019年39(9):5185-5206 ISSN：1078-0947
通讯作者：
Wang, Youming
作者机构：
[Wang, Youming; Liao, Liangwen; Yang, Fei] Nanjing Univ, Dept Math, Nanjing 210093, Jiangsu, Peoples R China.;[Wang, Youming] Hunan Agr Univ, Dept Appl Math, Changsha 410128, Hunan, Peoples R China.;[Zhang, Song] Chinese Acad Sci, Acad Math & Syst Sci, Beijing 100190, Peoples R China.
通讯机构：
[Wang, Youming] N;[Wang, Youming] H;Nanjing Univ, Dept Math, Nanjing 210093, Jiangsu, Peoples R China.;Hunan Agr Univ, Dept Appl Math, Changsha 410128, Hunan, Peoples R China.
关键词：
Singular perturbation;Julia sets;Cantor circles;connectivity;Hausdorff dimension
摘要：
<p style='text-indent:20px;'>In this paper, we investigate the dynamics of the following family of rational maps</p><p style='text-indent:20px;'><disp-formula> <label/> <tex-math id="FE1"> \begin{document}$ \begin{equation*} f_{\lambda}(z) = \frac{z^{2n} - \lambda^{3n+1}}{z^n(z^{2n} - \lambda^{n - 1})} \end{equation*} $\end{document} </tex-math> </disp-formula></p><p style='text-indent:20px;'>with one parameter <inline-formula><tex-math id="M1">\begin{document}$ \lambda \in \mathbb{C}^* - \{\lambda: \lambda^{2n + 2} = 1\} $\end{document}</tex-math></inline-formula>, where <inline-formula><tex-math id="M2">\begin{document}$ n\geq 2 $\end{document}</tex-math></inline-formula>. This family of rational maps is viewed as a singular perturbation of the bi-critical map <inline-formula><tex-math id="M3">\begin{document}$ P_{-n}(z) = z^{-n} $\end{document}</tex-math></inline-formula> if <inline-formula><tex-math id="M4">\begin{document}$ \lambda \neq 0 $\end{document}</tex-math></inline-formula> is small. It is proved that the Julia set <inline-formula><tex-math id="M5">\begin{document}$ J(f_\lambda) $\end{document}</tex-math></inline-formula> is either a quasicircle, a Cantor set of circles, a Sierpiński carpet or a degenerate Sierpiński carpet provided the free critical orbits of <inline-formula><tex-math id="M6">\begin{document}$ f_\lambda $\end{document}</tex-math></inline-formula> are attracted by the super-attracting cycle <inline-formula><tex-math id="M7">\begin{document}$ 0\leftrightarrow\infty $\end{document}</tex-math></inline-formula>. Furthermore, we prove that there exists suitable <inline-formula><tex-math id="M8">\begin{document}$ \lambda $\end{document}</tex-math></inline-formula> such that <inline-formula><tex-math id="M9">\begin{document}$ J(f_\lambda) $\end{document}</tex-math></inline-formula> is a Cantor set of circles but the dynamics of <inline-formula><tex-math id="M10">\begin{document}$ f_{\lambda} $\end{document}</tex-math></inline-formula> on <inline-formula><tex-math id="M11">\begin{document}$ J(f_{\lambda}) $\end{document}</tex-math></inline-formula> is not topologically conjugate to that of any known rational maps with only one or two free critical orbits (including McMullen maps and the generalized McMullen maps). The connectivity of <inline-formula><tex-math id="M12">\begin{document}$ J(f_{\lambda}) $\end{document}</tex-math></inline-formula> is also proved if the free critical orbits are not attracted by the cycle <inline-formula><tex-math id="M13">\begin{document}$ 0\leftrightarrow\infty $\end{document}</tex-math></inline-formula>. Finally we give an estimate of the Hausdorff dimension of the Julia set of <inline-formula><tex-math id="M14">\begin{document}$ f_\lambda $\end{document}</tex-math></inline-formula> in some special cases.</p>
语种：
英文
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3D MnO2 nanotubes@reduced graphene oxide hydrogel as reusable adsorbent for the removal of heavy metal ions
作者：
Zeng, Tianqin;Yu, Yong;Li, Zefan;Zuo, Jiangtao;Kuai, Zeyuan;...
期刊：
Materials Chemistry and Physics ,2019年231:105-108 ISSN：0254-0584
通讯作者：
Peng, Chang
作者机构：
[Peng, Chang; Wu, Anjun; Kuai, Zeyuan; Jin, Yang; Wang, Yehe; Li, Zefan; Yu, Yong; Zuo, Jiangtao; Zeng, Tianqin] Hunan Agr Univ, Coll Sci, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Peng, Chang] H;Hunan Agr Univ, Coll Sci, Changsha 410082, Hunan, Peoples R China.
关键词：
MnO2 nanotubes;Reduced graphene oxide;Hydrogel;Heavy metal ions;Adsorption capacity
摘要：
In this work, MnO2 [email protected] graphene oxide hydrogel (MNGH) was prepared via one-step hydrothermal co-assembly approach. The as-prepared MNGH exhibited three-dimensional (3D) architecture with a high surface area of 156 m2 g−1. By characterization of the morphology of MNGH, MnO2 nanotubes with uniform size (∼20 nm) were wrapped by interconnected porous reduced graphene oxide (rGO) sheets. Benefiting from the 3D porous nanostructure as well as the synergetic action between rGO and MNTs, the MNGH sample showed decent adsorption ability for various heavy metal ions (Pb2+, Cd2+, Ag+, Cu2+ and Zn2+). Especially, the adsorption capacity of Pb2+ on MNGH can reach 356.37 mg g−1 and the sorption datum fits the Langmuir model. Moreover, the adsorption performance of MNGH can be maintained after multiple regeneration experiments. These results demonstrated that the as-prepared MNGH could be applied as the promising adsorbent for removal of heavy metal ions. © 2019 Elsevier B.V.
语种：
英文
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Sulfuric acid-adjuvant sulfonated graphene as efficient polysulfides tamer for high-energy-density LiS batteries
作者：
Zhong, Mei-e;Sun, Jingchun;Guan, Jindiao;Liang, Ce;Yu, Shuang;...
期刊：
Journal of Power Sources ,2019年412:134-141 ISSN：0378-7753
通讯作者：
Zhou, Nan;Gong, Daoxin
作者机构：
[Zhong, Mei-e; Sun, Jingchun; Yu, Shuang; Zhou, Nan; Guan, Jindiao; Liang, Ce] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Xiao, Zhubing] Chinese Acad Sci, State Key Lab Struct Chem, Fujian Inst Res Struct Matter, 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.
关键词：
Li-S batteries;Sulfonated graphene;Polysulfides;Shuttle effect;Mediator
摘要：
Lithium-sulfur batteries hold great promise for large-scale energy storage owing to their high theoretical energy density and low cost. However, the insulating nature of sulfur and shuttle effect of polysulfides result in low sulfur utilization and rapid capacity decay. Here, sulfonated graphene is fabricated using the low-cost diluted sulfuric acid as sulfonated reagent, for constructing the freestanding sulfur cathode. It is confirmed that the sulfo groups grafted on graphene serve as mediators to react with long-chain polysulfides by forming the thiosulfate/polythionate intermediates, and facilitate the conversion of long-chain polysulfides into short-chain species and solid discharge products. Crucially, the freestanding cathode with sulfur loading of 8.2 mg cm−2 exhibits an areal capacity of 7.57 mA h cm−2 and stable cycling over 100 cycles at 0.1 C. © 2018
语种：
英文
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Attapulgite-supported nano-Fe0/peroxymonsulfate for quinclorac removal: Performance, mechanism and degradation pathway
作者：
Ding, Chunxia;Xiao, Sijia;Lin, Yingjun;Yu, Peng;Zhong, Mei-e;...
期刊：
Chemical Engineering Journal ,2019年360:104-114 ISSN：1385-8947
通讯作者：
Deng, Yaocheng;Gong, Daoxin
作者机构：
[Yu, Peng; Ding, Chunxia; Lin, Yingjun; Xiao, Sijia; Zhong, Mei-e] Hunan Agr Univ, Coll Sci, Changsha 410082, Hunan, Peoples R China.;[Su, Long; Yang, Lihua; Zhou, Yaoyu; Deng, Yaocheng; Gong, Daoxin; Liao, Chanjuan; Wang, Han] Hunan Agr Univ, Coll Resource & Environm, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Deng, YC; Gong, DX] H;Hunan Agr Univ, Coll Resource & Environm, Changsha 410082, Hunan, Peoples R China.
关键词：
Attapulgite;Peroxymonosulfate;Quinclorac;Removal;Zero valent iron
摘要：
A nanocomposite of nZVI/ATP with nanoscale zero-valent iron(nZVI) supported on attapulgite(ATP) was synthesized for activating peroxymonosulfate (PMS) to generate reactive free radicals for quinclorac removal. The microstructures of nZVI/ATP were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, Scanning electron microscopy, and N2 adsorption-desorption. The effect factors of nZVI/ATP-PMS system on quinclorac degradation were tested, including PMS dosage, nZVI/ATP dosage, initial solution pH, initial quinclorac concentration, common existing ions and temperature. Quinclorac degradation products were identified by LC-MS/MS, and the possible degradation mechanism was proposed. The results showed that nanoscale zero-valent iron (nZVI) was evenly dispersed on the attapulgite surface, which effectively prevents the agglomeration and oxidation of nZVI and improves its catalytic performance. The removal efficiency of quinclorac was 97.36%, in an hour using 0.5 g/L nZVI/ATP3 and 10 mM PMS. The total organic carbon was removed as high as 79.97%. Quinclorac was degraded into five major products by chemical reactions of hydroxyl substitution, oxidation and ring-cleavage. Finally, most of the degradation products were mineralized into inorganics such as CO2, H2O or something else. It turned out that nZVI/ATP-PMS was a highly efficient catalytic degradation system for removing quinclorac residues in aqueous solution. © 2018 Elsevier B.V.
语种：
英文
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Palladium-Catalyzed Aerobic Benzannulation of Amines, Benzaldehydes, and β‑Dicarbonyls
作者：
Xia, Yujia;Huang, Huawen* ;Zhang, Feng;Deng, Guo-Jun*
期刊：
Organic Letters ,2019年21(18):7489-7492 ISSN：1523-7060
通讯作者：
Huang, Huawen;Deng, Guo-Jun
作者机构：
[Deng, Guo-Jun; Huang, Huawen; Deng, GJ; Xia, Yujia; Zhang, Feng] Xiangtan Univ, Coll Chem, Minist Educ,Key Lab Environm Friendly Chem & Appl, Key Lab Green Organ Synth & Applicat Hunan Prov, Xiangtan 411105, Peoples R China.;[Zhang, Feng] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Huang, HW; Deng, GJ] X;Xiangtan Univ, Coll Chem, Minist Educ,Key Lab Environm Friendly Chem & Appl, Key Lab Green Organ Synth & Applicat Hunan Prov, Xiangtan 411105, Peoples R China.
摘要：
A palladium-catalyzed aerobic multicomponent benzannulation of Hantzsch reactants, i.e., amines, aldehydes, and β-dicarbonyls, has been developed. Hence, a viable entry to highly functionalized anilines has been accessed under solvent-free neat conditions. Mechanistically, the palladium chelating with an imine intermediate was proposed to be the key for this novel carbocyclization.
语种：
英文
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Phosphorus and oxygen co-doped composite electrode with hierarchical electronic and ionic mixed conducting networks for vanadium redox flow batteries
作者：
Ling, Wei;Wang, Zhi-An;Ma, Qiang;Deng, Qi;Tang, Jian-Feng;...
期刊：
Chemical Communications ,2019年55(77):11515-11518 ISSN：1359-7345
通讯作者：
Wu, Xiong-Wei;Yue, Jun-Pei;Guo, Yu-Guo
作者机构：
[Ma, Qiang; Deng, Lei; Wu, Xiong-Wei; Tang, Jian-Feng; Ling, Wei; Deng, Qi] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Wang, Zhi-An] Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Zhu, Liang-Hong] Shenzhen Polytech, Automot & Transportat Engn, Shenzhen 518055, Guangdong, Peoples R China.;[Yue, Jun-Pei; Guo, Yu-Guo] Chinese Acad Sci, CAS Key Lab Mol Nanostruct & Nanotechnol, Inst Chem, Beijing 100190, Peoples R China.
通讯机构：
[Wu, Xiong-Wei] H;[Yue, JP; Guo, YG] C;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Chinese Acad Sci, CAS Key Lab Mol Nanostruct & Nanotechnol, Inst Chem, Beijing 100190, Peoples R China.
摘要：
The hierarchical electronic and ionic mixed conducting networks build in graphite felt electrodes possess excellent electrocatalytic activity and faster electronic and ionic conduction, resulting in an enhanced energy efficiency of vanadium redox flow batteries with durable life for 1000 cycles and a high discharge capacity of 10.1 A h L-1 at a current density of 350 mA cm-2. This journal is © The Royal Society of Chemistry.
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英文
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甜茶苷和甜茶多酚同时提取工艺优化
作者：
向锋;董新荣;曾建国
期刊：
食品工业科技 ,2019年40(6):173-178 ISSN：1002-0306
作者机构：
湖南中医药大学药学院;湖南农业大学理学院;[董新荣] 湖南农业大学;[曾建国; 向锋] 湖南中医药大学
关键词：
甜茶苷;甜茶多酚;响应面法;提取工艺
摘要：
采用响应面法优化以水为溶剂同时提取广西甜茶干叶中的甜茶苷和甜茶多酚的工艺.利用Box-Behnken响应面分析法,以甜茶苷提取率和甜茶多酚提取率为响应值,优化了同时提取甜茶苷和甜茶多酚的最佳工艺为:提取温度57℃,液料比为25∶1 mL/g,提取时间为36 min,在此条件下,甜茶多酚提取率为85.32％(RSD=1.42％,n=3),甜茶苷的提取率为83.58％(RSD=2.24％,n=3).该研究结果为甜茶叶的综合利用提供了实验依据.
语种：
中文
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Enhancing quantum efficiency and tuning photoluminescence properties in far-red-emitting phosphor Ca14Ga10Zn6O35:Mn4+ based on chemical unit engineering
作者：
Zhong, Yuan;Gai, Shujie;Xia, Mao;Gu, Simin;Zhang, Yongli;...
期刊：
Chemical Engineering Journal ,2019年374:381-391 ISSN：1385-8947
通讯作者：
Zhou, Nan;Zhou, Zhi
作者机构：
[Xia, Mao; Zhang, Yongli; Zhong, Yuan; Gai, Shujie; Zhou, Nan; Zhou, Zhi; Wu, Xianbo; Gu, Simin] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Wang, Jing] Sun Yat Sen Univ, Sch Chem, State Key Lab Optoelect Mat & Technol, Guangzhou 510275, Guangdong, Peoples R China.;[Wang, Jing] Sun Yat Sen Univ, Sch Mat Sci & Engn, Guangzhou 510275, Guangdong, Peoples R China.
通讯机构：
[Zhou, N; Zhou, Z] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
Ca14Ga10Zn6O35:Mn4+;Chemical unit engineering;Plant growth LED lighting;Quantum efficiency;Tunable emission
摘要：
Mn4+ activated Ca14Ga10Zn6O35 (CGZO)have attracted much attention for the usages of white light-emitting-diodes (WLEDs), solar cells and plant growth LEDs. In this paper, we conducted chemical unit engineering in CGZO:Mn4+ by substituting Ge4+-M+ (M = Li, Na, K)for Ga3+-Ca2+. The impacts of Ge4+-M+ (M = Li, Na, K)substitution on the crystal structure, photoluminescence properties, quantum efficiency (QE)and thermal stability were investigated systematically. With the increase of Ge4+-Li+/Na+ and Ge4+-K+, the diffraction peaks moved towards higher and lower angle, respectively. The greatest improvement of emission intensity in Ge4+-Li+/Na+/K+ co-doped CGZO:Mn4+ reached up to 169.4%, 195.0% and 198.9%. Moreover, an obvious red shift (∼3.6 nm)was detected in Ge4+-Li+ case and this change was interpreted by Tanabe–Sugano diagram. The IQE and EQE of Ge4+-Li+/Na+/K+ co-doped CGZO:Mn4+ showed remarkable improvements. The highest values of IQE and EQE were found to be 50.9% and 38.9% in Ge4+-K+ incorporated sample. Furthermore, conducting chemical unit engineering in CGZO:Mn4+ could slightly enhance its thermal stability. The configurational coordinated diagram was employed to understand this enhancement comprehensively. Finally, LED devices were fabricated by using Ge4+-Li+ co-doped CGZO:Mn4+ phosphor as light convertor. The excellent electronic luminescence (EL)properties and matchable emission with the absorption of plant pigments demonstrating that these phosphors have promising application in plant growth LED lighting. © 2019 Elsevier B.V.
语种：
英文
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Photocontrolled self-assembly of silica nanoparticles
作者：
Peng, Chang;Zeng, Tianqin;Yu, Yong;Li, Zefan;Zuo, Jiangtao;...
期刊：
Ceramics International ,2019年45(7):9320-9324 ISSN：0272-8842
通讯作者：
Li, Ling
作者机构：
[Peng, Chang; Li, Ling; Kuai, Zeyuan; Jin, Yang; Wang, Yehe; Li, Zefan; Yu, Yong; Zuo, Jiangtao; Zeng, Tianqin] Hunan Agr Univ, Coll Sci, Changsha 410082, Hunan, Peoples R China.;[Peng, Chang] Hunan Agr Univ, Hunan Opt Agr Engn Technol Res Ctr, Changsha, Hunan, Peoples R China.
通讯机构：
[Li, Ling] H;Hunan Agr Univ, Coll Sci, Changsha 410082, Hunan, Peoples R China.
关键词：
Light controlled self-assembly;Morphological patterns;Reversible photoresponse
摘要：
Herein we present a novel light-controlled assembly system, which is fabricated by functionalizing silica nanoparticles with coumarin. This system exhibits reversible morphological changes under alternating irradiation with 365 nm and 254 nm light: scattered distribution pattern, firework-shaped pattern, honeycomb pattern and donut-like pattern, due to the reversible photodimerization and photocleavage of coumarin. Furthermore, this system displays reversibly controllable wettability, which can be transformed between hydrophobic and superhydrophobic upon UV light illumination based on the photoresponsive of coumarin as well. The system with these interesting characteristics provides potential applications in the synthesis of controllable nanostructures by photo-regulation and self-cleaning fields. © 2019
语种：
英文
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Enhancing photoluminescence properties of Mn4+-activated Sr4-xBaxAl14O25 red phosphors for plant cultivation LEDs
作者：
Wu, Xianbo;Yang, Yimei;Gai, Shujie;Liu, Longhai;Zhou, Zhipeng;...
期刊：
Journal of the American Ceramic Society ,2019年102(12):7386-7396 ISSN：0002-7820
通讯作者：
Zhou, Nan;Zhou, Zhi
作者机构：
[Xia, Mao; Zhou, Zhipeng; Yang, Yimei; Gai, Shujie; Zhong, Yuan; Zhou, Nan; Zhou, Zhi; Wu, Xianbo; Liu, Longhai; Li, Minghui] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Xia, Mao; Zhou, Zhipeng; Yang, Yimei; Gai, Shujie; Zhong, Yuan; Wu, Xianbo; Zhou, Nan; Zhou, Zhi; Liu, Longhai; Li, Minghui] Hunan Agr Univ, Hunan Opt Agr Engn Technol Res Ctr, Changsha, Hunan, Peoples R China.
通讯机构：
[Zhou, N; Zhou, Z] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
LED;luminescence;phosphors;plant cultivation;Sr4Al14O25:Mn4+
摘要：
Non-rare earth Mn4+-activated strontium aluminate phosphor is considered to be a promising material for plant cultivation field owing to their advantage of inexpensively, environment friendly, nontoxic, and appropriate spectral range. In this paper, a Sr4-xBaxAl13.99O25:0.01Mn(4+),1.4H(3)BO(3) strontium aluminate phosphor is synthesized by a convenient high-temperature solid-state reaction. The photoluminescence spectra located at red region with a peak at 655 nm in the range of 600 to 750 nm that can be excited under the excitation of ultraviolet (similar to 346 nm) or blue light (similar to 450 nm). The shape emission band at 655 nm is attributed to the transition of E-2(g)-(4)A(2g). Furthermore, the emission intensity of Sr4-xBaxAl13.99O25: 0.01Mn(4+),1.4H(3)BO(3) phosphor is conducted in detail with the variety of Ba2+ doping concentration and the intensity can be enhanced to 140.9% than the Sr4Al13.99O25:0.01Mn(4+),1.4H(3)BO(3) when the value of Ba2+ concentration equal to 0.1 mol. In addition, the X-ray diffraction spectra, element mapping, composition modifying, optical properties, FT-IR spectra, diffuse reflectance spectra, thermal stability, and fluorescence lifetime are systematically investigated. According to the electro-luminescent spectra of as-packaged LED, indicating that the Sr3.9Ba0.1Al13.99O25:0.01Mn(4+),1.4H(3)BO(3) phosphor will become a great candidate for plant cultivation LEDs due to the emission spectra match well the plant pigment spectrum.
语种：
英文
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Surface-Wrinkle-Modified Graphite Felt with High Effectiveness for Vanadium Redox Flow Batteries
作者：
Chen, Zehua;Gao, Yu;Zhang, Chuanxiang* ;Zeng, Xianxiang;Wu, Xiongwei*
期刊：
Advanced Electronic Materials ,2019年5(7):1900036- ISSN：2199-160X
通讯作者：
Zhang, Chuanxiang;Wu, Xiongwei
作者机构：
[Zhang, Chuanxiang; Gao, Yu; Chen, Zehua] Henan Polytech Univ, Coll Chem & Chem Engn, Jiaozuo 454000, Henan, Peoples R China.;[Chen, Zehua] Tsinghua Univ, Sch Mat Sci & Engn, Beijing 100084, Peoples R China.;[Zeng, Xianxiang; Wu, Xiongwei] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Zhang, Chuanxiang; Wu, Xiongwei] H;Henan Polytech Univ, Coll Chem & Chem Engn, Jiaozuo 454000, Henan, Peoples R China.;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
关键词：
all-vanadium redox flow batteries;fast ion conduction;graphite felt;surface-wrinkle modification
摘要：
Surface-wrinkle-modified graphite felt (GF) with abundant N and O is prefabricated by a hydrothermal method followed by calcination, and its surface morphology, elemental composition, and electrochemical properties are characterized by scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and charge/discharge tests. The highly folded coating has excellent wettability, abundant catalytic sites, a fast ion-diffusion rate, ultralow interface transfer resistance, and high catalytic activity for VO2+/VO2+ and V2+/V3+ reaction couples. Compared with the original GF, the modified GF greatly increases the redox reversibility of the VO2+/VO2+ and V2+/V3+ couples according to cyclic voltammetry profiles. The cathodic and anodic peak potential difference for VO2+/VO2+ substantially decreases from 542 to 388 mV. A battery based on surface-wrinkle-modified GF exhibits overall improved efficiency, higher power density, and a high reversible efficiency with a stable average energy efficiency of 78% at a current density of 150 mA cm−2 for 200 charge/discharge cycles. © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
语种：
英文
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MoS2-Catalyzed transamidation reaction
作者：
Zhang, Feng* ;Li, Lesong;Ma, Juan;Gong, Hang*
期刊：
Scientific Reports ,2019年9(1):2536 ISSN：2045-2322
通讯作者：
Zhang, Feng;Gong, Hang
作者机构：
[Zhang, Feng] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Li, Lesong; Ma, Juan; Gong, Hang] Xiangtan Univ, Coll Chem, Minist Educ, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Peoples R China.
通讯机构：
[Zhang, Feng] H;[Gong, Hang] X;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Xiangtan Univ, Coll Chem, Minist Educ, Key Lab Environm Friendly Chem & Applicat, Xiangtan 411105, Peoples R China.
摘要：
The MoS2-catalyzed transamidation reaction with high yields using N,N-dimethylformamide and other amides as carbonyl sources is developed here. The protocol is simple, does not require any additive such as acid, base, ligand, etc., and encompasses a broad substrate scope for primary, secondary and heterocyclic amines. Moreover, the acetylation and propanylation of amines also can be achieved with good to excellent yield by this strategy.
语种：
英文
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Recent advances in nanostructured electrode-electrolyte design for safe and next-generation electrochemical energy storage
作者：
Zeng, X-X;Xu, Y-T;Yin, Y-X;Wu, X-W* ;Yue, J.* ;...
期刊：
Materials Today Nano ,2019年8:100057 ISSN：2588-8420
通讯作者：
Wu, X-W;Yue, J.;Guo, Y-G
作者机构：
[Wu, X-W; Xu, Y-T; Zeng, X-X] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Yue, J.; Yin, Y-X; Guo, Y-G] Chinese Acad Sci, CAS Res Educ Ctr Excellence Mol Sci, CAS Key Lab Mol Nanostruct & Nanotechnol, Inst Chem,Beijing Natl Lab Mol Sci BNLMS, Beijing 100190, Peoples R China.;[Yin, Y-X; Guo, Y-G] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.;[Wu, X-W] Cent South Univ, XiangYa Sch Publ Hlth, Changsha 410078, Hunan, Peoples R China.
通讯机构：
[Wu, X-W] H;[Yue, J; Guo, YG; Wu, X-W] C;[Guo, Y-G] U;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Chinese Acad Sci, CAS Res Educ Ctr Excellence Mol Sci, CAS Key Lab Mol Nanostruct & Nanotechnol, Inst Chem,Beijing Natl Lab Mol Sci BNLMS, Beijing 100190, Peoples R China.
关键词：
Electrochemical energy storage;Energy density;Nanomaterials;Power;Safety;Structure design
摘要：
The pursuit for high-efficiency energy utilization stimulates for rapid development of electrochemical storage techniques. While the energy density demand is elevated, the safety consideration has stepped onto a new height. Hence, these two aspects gain much attention in the evolution of electrochemical energy storage. Correspondingly, the electrodes and electrolytes need special design to achieve the set target. This review first collects recent progress in nanostructured electrode-electrolyte with tailored design, including specific attention on alkali metal batteries, redox flow batteries, and supercapacitors. The electrode materials along with advanced electrolytes can endow these electrochemical energy storage apparatuses with high energy or power density, long lifetime, and high safety insurance. Moreover, the particular focus is dedicated to practical concerns for these electrodes, electrolytes, and their interfaces, including the thermal behavior and charging/discharging changing of an electrode, electrolyte selection and optimization, and electrode-electrolyte interface construction. Eventually, the general guideline and direction of endeavor to break the current limitation are presented for advanced electrochemical energy storage in the future. © 2019 Elsevier Ltd
语种：
英文
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木本泥炭对Cr( Ⅵ)的吸附性能
作者：
席改红;石国荣;李强;李亚婷;徐琴琴;...
期刊：
环境化学 ,2019年38(1):202-208 ISSN：0254-6108
作者机构：
[石国荣; 席改红] 湖南农业大学生命科学技术学院,长沙,410128;[石国荣] 湖南农业大学理学院,长沙,410128;湖南农业大学农学院,长沙,410128;[李强; 徐琴琴; 李小雨; 李亚婷] 湖南农业大学
关键词：
木本泥炭;吸附;解吸附
摘要：
以木本泥炭为吸附材料,用于去除水中的Cr( Ⅵ) .研究了溶液pH值、吸附时间、木本泥炭用量、缓冲液浓度和初始浓度对Cr( Ⅵ)吸附的影响,以及溶液pH值对Cr( Ⅵ)解吸附的影响.结果表明,木本泥炭对 Cr( Ⅵ)的去除率随溶液pH值的增大而减小,当溶液pH值为4时,木本泥炭对Cr( Ⅵ)的吸附能力最强, 3.33 g·L~(-1)木本泥炭对100 mg·L~(-1) Cr( Ⅵ)的吸附量为29. 98 mg·g~(-1) ;当磷酸盐缓冲液浓度在0. 10-0.20 mol·L~(-1)范围内时,随着缓冲液浓度的增大Cr( Ⅵ)的吸附量逐渐减小;木本泥炭对Cr( Ⅵ)的吸附符合准一级反应动力学,其吸附等温线符合Langmuir吸附模型;当溶液pH值小于6时,Cr( Ⅵ)的解吸率低于0.32%.
语种：
中文
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Highly Active Co-Based Catalyst in Nanofiber Matrix as Advanced Sensing Layer for High Selectivity of Flexible Sensing Device
作者：
Wang, Kang;Li, Jing;Li, Wei;Wei, Wei;Zhang, Hao;...
期刊：
Advanced Materials Technologies ,2019年4(2):1800521- ISSN：2365-709X
通讯作者：
Wang, Lili
作者机构：
[Wang, Lili; Wang, Kang] Jilin Univ, State Key Lab Integrated Optoelect, Coll Elect Sci & Engn, Changchun 130012, Jilin, Peoples R China.;[Li, Jing] Jilin Univ, Hosp 1, Ctr Cardiovasc Dis, Changchun 130021, Peoples R China.;[Li, Wei] Hunan Agr Univ, Coll Sci, Changcha 410128, Peoples R China.;[Wei, Wei] Jilin Univ, Lab Theoret & Computat Chem, Inst Theoret Chem, Changchun 130012, Jilin, Peoples R China.;[Zhang, Hao] Shenzhen Technol Univ, Coll Hlth & Environm Engn, Shenzhen 518118, Peoples R China.
通讯机构：
[Wang, Lili] J;Jilin Univ, State Key Lab Integrated Optoelect, Coll Elect Sci & Engn, Changchun 130012, Jilin, Peoples R China.
关键词：
1D heteronanofibers;density functional theory;flexible sensing devices;high active facets;high selective sensitivity
摘要：
An efficient and economic sensing material for flexible chemical sensors is increasingly in great demand as a result of its potential application in the healthcare and environmental detection systems. Endowing the nanomaterials with high active facets serves as a promising method for the design of nanomaterials with advanced functionalities. New physicochemical properties of chemical sensor can be obtained by using high active facets nanoparticles combined in one-dimensional (1D) nanofiber/wires. However, it remains a great challenge to conduct the development of 1D heterostructure sensing materials with high selectivity, in particular the ones that can perform under room temperature. Here, a high performance flexible sensing device based on Co3O4 nanoparticles with specific (112) facet in α-Fe2O3 nanofiber is reported. The heterointerfaces and grain boundary allow the fast electrons transportation in sensing reactions and the (112) facets in Co3O4 nanoparticles provide a large number of highly active sites where the selective absorption of ammonia gas molecules occurs. Consequently, the flexible gas sensor exhibits ultrahigh sensitivity (417%) and mechanical stability to ammonia gas molecules, which are proved by using density functional theory calculations. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
语种：
英文
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Influence of Defects on Excited-State Dynamics in Lead Halide Perovskites: Time-Domain ab Initio Studies
作者：
Li, Wei* ;Long, Run* ;Tang, Jianfeng* ;Prezhdo, Oleg V.*
期刊：
Journal of Physical Chemistry Letters ,2019年10(13):3788-3804 ISSN：1948-7185
通讯作者：
Li, Wei;Tang, Jianfeng;Long, Run;Prezhdo, Oleg V.
作者机构：
[Tang, Jianfeng; Li, Wei; Li, W] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Long, Run] Beijing Normal Univ, Minist Educ, Key Lab Theoret & Computat Photochem, Coll Chem, Beijing 100875, Peoples R China.;[Prezhdo, Oleg V.] Univ Southern Calif, Dept Chem, Los Angeles, CA 90089 USA.
通讯机构：
[Li, W; Tang, JF] H;[Long, Run] B;[Prezhdo, Oleg V.] U;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Beijing Normal Univ, Minist Educ, Key Lab Theoret & Computat Photochem, Coll Chem, Beijing 100875, Peoples R China.
摘要：
This Perspective summarizes recent research into the excited-state dynamics in lead halide perovskites that are of paramount importance for photovoltaic and photocatalytic applications. Nonadiabatic molecular dynamics combined with time-domain ab initio density functional theory allows one to mimic time-resolved spectroscopy experiments at the atomistic level of detail. The focus is placed on realistic aspects of perovskite materials, including point defects, surfaces, grain boundaries, mixed stoichiometries, dopants, and interfaces. The atomistic description of the quantum dynamics of electron and hole trapping and recombination, provided by the time-domain ab initio simulations, generates important insights into the mechanisms of charge and energy losses and guides the development of high-performance perovskite solar cell devices.
语种：
英文
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胆碱/谷氨酸离子液体微波辅助提取栀子活性成分的研究
作者：
李奎;王梓瑜;文志勇;董新荣
期刊：
广州化工 ,2019年47(12):81-86 ISSN：1001-9677
作者机构：
湖南农业大学理学院,湖南 长沙,410128;[文志勇; 王梓瑜; 董新荣; 李奎] 湖南农业大学
关键词：
栀子;离子液体;栀子苷;栀子黄色素;绿原酸
摘要：
研究了[胆碱][谷氨酸]离子液体([Ch][Glu]IL)水溶液提取栀子活性成分的方法.以栀子黄色素、 绿原酸、 栀子苷三者收率为考察指标,用响应面优化了微波辅助提取栀子活性成分的条件.最佳条件为:[胆碱][谷氨酸]离子液体水浓度1.4％、液料比25.5 mL/g、 微波功率320 W、 微波处理时间305 s.在此条件下,栀子黄色素、 绿原酸、 栀子苷的收率可达49.58、17.23、71.82 mg/g.[Ch][Glu]IL水溶液提取栀子活性成分具有时间短、 效率高、 环境友好等优点,为栀子活性成分的获得提供了新方法.
语种：
中文
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Ultrasound accelerated synthesis of O-alkylated hydroximides under solvent- and metal-free conditions
作者：
Jiang, Hongmei;Tang, Xiaoyue;Liu, Sihan;Wang, Lian;Shen, Haicheng;...
期刊：
Organic & Biomolecular Chemistry ,2019年17(48):10223-10227 ISSN：1477-0520
通讯作者：
Gui, Qing-Wen
作者机构：
[Wang, Lian; Yang, Jiankui; Shen, Haicheng; Gui, Qing-Wen; Liu, Sihan; Wang, Huixian; Jiang, Hongmei] Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Jiang, Hongmei] Hunan Univ, Coll Chem Engn, State Key Lab ChemoBiosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Tang, Xiaoyue] South China Univ Technol, Sch Chem & Chem Engn, Dept Pharmaceut Engn, Guangzhou 510640, Guangdong, Peoples R China.
通讯机构：
[Gui, Qing-Wen] H;Hunan Agr Univ, Coll Sci, Changsha 410128, Hunan, Peoples R China.
摘要：
A novel, sustainable, environmentally friendly, high substrate scope, efficient, solvent-free and metal catalyst-free method for the cross-dehydrogenative coupling (CDC) reaction between N-hydroxyphthalimide (NHPI) and benzyl/ether compounds is described. This coupling reaction proceeds through ultrasound acceleration. Compared to conventional heating conditions, the use of ultrasound techniques not only improves the reaction efficiency and enhances the reaction rate but also minimizes the side reactions.
语种：
英文
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