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The catalytic effect of bismuth for VO2+/VO2+and V3+/V2+redox couples in vanadium flow batteries

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Journal of Energy Chemistry 2017年第1期26卷 1-7页

作者： xiaofei yang Tao Liu Chi Xu Hongzhang Zhang Xianfeng Li Huamin Zhang Division of Energy Storage Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100039China Collaborative Innovation Center of Chemistry for Energy Materials(iChEM) Dalian 116023LiaoningChina

The effect of bismuth (Bi) for both VO2+/VO2+ and V3+/V2+ redox couples in vanadium flow batteries (VFBs) has been investigated by directly introducing Bi on the surface of carbon felt (CF). The results show that Bi has no catalytic effect for VO2+/VO2(+) redox couple. During the first charge process, Bi is oxidized to Bi3+ (never return back to Bi metal in the subsequent cycles) due to the low standard redox potential of 0.308 V (vs. SHE) for Bi3+/Bi redox couple compared with VO2+/VO2+ redox couple and Bi3+ exhibit no (or neglectable) electro-catalytic activity. Additionally, the relationship between Bi loading and electrochemical activity for V3+/V2+ redox couple was studied in detail. 2 wt% Bi-modified carbon felt (2%-BiCF) exhibits the highest electrochemical activity. Using it as negative electrode, a high energy efficiency (EE) of 79.0% can be achieved at a high current density of 160 mA/cm(2), which is 5.5% higher than the pristine one. Moreover, the electrolyte utilization ratio is also increased by more than 30%. Even the cell operated at 140 mA/cm(2) for over 300 cycles, the EE can reach 80.9% without obvious fluctuation and attenuation, suggesting excellent catalytic activity and electrochemical stability in VFBs. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.

关键词： Vanadium flow battery Bismuth Catalysis Electrochemical activity Energy efficiency

Effect of Ni doping on the microstructure and magnetic properties of FePt films

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Rare Metals 2009年第3期28卷 257-260页

作者： DONG Kaifeng CHENG Xiaomin YAN Junbing CHENG Weiming LI Peng yang xiaofei Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

FePtNi films with different Ni contents were deposited on glass substrates by RF magnetron sputtering, and the L10-FePtNi films were obtained after the asdeposited samples were subjected to vacuum annealing. The magnetic properties, structures, and orientations of the L10-FePt films with Ni doping were studied. The results show that with increasing Ni content, the （001） peak position of the FePtNi films shifts to a higher angle in comparison with FePt, which suggests that there is partial Ni substitution in the L10 lattice. The perpendicular coercivity decreases from 661 to 142 kA/m and magnetization decreases from 512 to 433 kA/m with increasing Ni content. In comparison with FePt films, the FePtNi films can effectively reduce the Curie temperature, which makes FePtNi films promising media candidates in thermally assisted recording （TAR）.

关键词： FePtNi films Curie temperature magnetization coercivity

Light-and Heat-Controlled Formation of Osmanaphthalenes and Osmanaphthalynes

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Chinese Journal of Chemistry 2022年第24期40卷 2853-2860页

作者： Ming-Xing Zhang xiaofei yang Zhiqiang Xu Jun Yin Sheng Hua Liu Key Laboratory of Pesticide and Chemical Biology Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhanHubei430079 China Hubei Key Laboratory of Purification and Application of Plant Anti-cancer Active Ingredients College of Chemistry and Life ScienceHubei University of EducationWuhanHubei430205 China Key Laboratory for Green Chemical Process of Ministry of Education School of Chemical Engineering and PharmacyWuhan Institute of TechnologyWuhanHubei430205 China

mple and efficient synthesis of metalla-aromatics with tailored distinctive optical,magnetic,redox,and light-emitting properties is attractive yet *** have now successfully synthesized three paramagnetic osmanaphthalenes bearing different electron-donating groups as well as the first osmabenzo[b]carbazole containing an osmanaphthalene unit with four fused rings in good yields by subjecting suitable osmium carbyne precursors to a visible-light-induced *** contrast,the four corresponding diamagnetic cyclic metal carbynes containing an osmanaphthalyne unit were obtained from the same osmium carbyne precursors by a heating *** lowest-energy absorptions of the paramagnetic osmanaphthalenes are red-shifted compared to the corresponding ***,experimental observations including X-ray analysis as well as nucleus-independent chemical shift(NICS),anisotropy of the current-induced density(AICD)calculations revealed these novel osmapolycycles bearing phosphonium substituents to be of aromatic character.

关键词： Metallacycles Aromaticity Osmanaphthalyne Osmanaphthalene Photolysis

Enhancement in the Response of Pb(Zr,Ti)O_3/Terfenol-D/Metglas Magnetoelectric Laminate Composites

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Journal of Wuhan University of Technology(Materials Science) 2013年第4期28卷 664-667页

作者：李杨欧阳君 TONG Bei CHEN Shi yang xiaofei School of Optical and Electronic Information Huazhong University of Science & Technology

The magnetic field response results on a five-layer structure given as Metglas/Terfenol-D/ Pb（Zr,Ti）O3frerfenol-D/Metglas were reported. Due to its high permeability, Metglas can be incorporated as the third phase into conventional Pb（Zr, Ti）OJTerfenol-D laminates, which results in a stronger magnetoelectric（ME） response. The increase in Metglas thickness significantly influences the ME response as well. The ME voltage coefficient for a structure with a 150 grn thick Metglas layer on both sides of Terfenol-D/Pb（Zr, Ti）O3 laminates at 1 kHz was found to be 1.2 V/cmOe at dc magnetic bias field of 590 Oe under an ac magnetic drive of 1 Oe, which was notably higher in comparison to similar structures with other different Metglas thickness. Key words： laminates composites; magnetoelectric response; magnetic field; Metglas thickness

关键词： laminates composites magnetoelectric response magnetic field Metglas thickness

我国滨海典型生态系统修复主要技术及问题探讨

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海洋技术学报 2024年第3期43卷 72-81页

作者：刘霜温国义张继民杨晓飞山东省海洋生态环境与防灾减灾重点实验室山东青岛266061 自然资源部渤海生态预警与保护修复重点实验室山东青岛266033 国家海洋局北海环境监测中心山东青岛266033

滨海生态系统修复是我国海洋生态保护工作的重要部分,众多海洋生态修复项目在全国各地陆续获批实施,修复技术研究面临着更高的要求。本文从海洋生态系统修复的模式划分出发,梳理了滨海盐沼、潮滩、海草床、红树林、珊瑚礁、牡蛎礁等典... 详细信息

滨海生态系统修复是我国海洋生态保护工作的重要部分,众多海洋生态修复项目在全国各地陆续获批实施,修复技术研究面临着更高的要求。本文从海洋生态系统修复的模式划分出发,梳理了滨海盐沼、潮滩、海草床、红树林、珊瑚礁、牡蛎礁等典型类型的常见修复技术;简要介绍了多种修复技术的技术瓶颈;指出目前我国海洋生态修复存在的一些问题,如生态系统修复理论研究不足,修复手段以人工为主,对生态系统功能修复的重视不够,修复的时空尺度的衔接性和延续性欠缺;提出了亟待解决的关键技术问题,如高效低成本海草床修复关键技术尚待突破,珊瑚礁修复关键技术尚在发展中,红树林宜林地的选择和退塘还林技术有待提高;并提出今后应该以生态修复的顶层谋划为引领,进一步加强相关研究。

关键词：滨海典型生态系统生态修复技术技术瓶颈技术突破实践应用

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基于局部保留投影的稀疏中智聚类算法

计算机与数字工程 2024年第2期52卷 307-314,320页

作者：张丹马盈仓杨小飞邢志伟西安工程大学理学院西安710600

聚类算法是机器学习领域重要的研究课题之一,传统的中智聚类算法(例如FC-PFS算法)未考虑局部空间结构,且距离的计算受到冗余特征影响,不能有效处理高维数据集。为此,提出一种新的基于局部保留投影的稀疏中智聚类算法(LPSNCM)及其优化方... 详细信息

聚类算法是机器学习领域重要的研究课题之一,传统的中智聚类算法(例如FC-PFS算法)未考虑局部空间结构,且距离的计算受到冗余特征影响,不能有效处理高维数据集。为此,提出一种新的基于局部保留投影的稀疏中智聚类算法(LPSNCM)及其优化方法。一方面LPSNCM算法通过局部保留投影方法生成具有局部结构信息的正交投影空间,另一方面通过特征提取方法可以减少特征数量以获得更有效的特征,从而增强了FC-PFS算法处理高维数据的能力。LPSNCM算法也可以被看作是谱聚类两个独立阶段的统一模型。在一些基准数据集上的实验结果表明,与FC-PFS和某些最新方法相比,证明了LPSNCM的有效性。

关键词：中智集局部信息保留基于投影的空间转化

Quantum correlations in a chain-type quantum network

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Communications in Theoretical Physics 2024年第6期76卷 77-91页

作者： xiaofei Qi Aihong Zhai Lihua yang School of Mathematical Science Shanxi UniversityTaiyuan 030006China Key Laboratory of Complex Systems and Data Science of Ministry of Education Shanxi UniversityTaiyuan 030006China School of Mathematics and Information Technology Yuncheng UniversityYuncheng 044000China

A quantum network concerns several independent entangled resources and can create strong quantum correlations by performing joint measurements on some *** this paper,we discuss an n-partite chain network with each of two neighboring observers sharing an arbitrary Bell state and all intermediate observers performing some positive-operator-valued measurements with parameterλ.The expressions of all post-measurement states between any two observers are obtained,and their quantifications of Bell nonlocality,Einstein-Podolsky-Rosen steering and entanglement with different ranges ofλare respectively detected and analyzed.

关键词： quantum correlation nonlocality entanglement chain-type quantum network

Progress of super-resolution near-field structure in near-field optical storage technology

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Frontiers of Optoelectronics 2008年第Z2期1卷 292-298页

作者： xiaofei yang Qian LI Xiaomin CHENG Department of Electronics Sciences and Technology Huazhong University of Science and Technology

Super-resolution near-field structure(Super-RENS) is one of the most promising near-field optical recording schemes with significant application *** development of Super-RENS from the basic type to the third-generation is introduced. The development of mask material and the application of Super-RENS in different recording systems are summarized.

关键词： super-resolution near-field structure (Super-RENS) mask material third-generation Super-RENS recording system

宫腔负压吸引术联合宫腔镜冷刀切除术治疗多发性子宫内膜息肉的效果

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中国实用医刊 2024年第17期51卷 36-39页

作者：杨晓飞薛惠英裴慧慧胡捷安阳市人民医院妇产科安阳

目的分析宫腔负压吸引术联合宫腔镜冷刀切除术(HCKR)治疗多发性子宫内膜息肉(EMP)的效果。方法队列研究。抽取2019年1月至2021年12月安阳市人民医院收治的94例多发性EMP患者, 按随机数字表法分为宫腔镜下电刀切除术(HER)组和HCKR组, 每... 详细信息

目的分析宫腔负压吸引术联合宫腔镜冷刀切除术(HCKR)治疗多发性子宫内膜息肉(EMP)的效果。方法队列研究。抽取2019年1月至2021年12月安阳市人民医院收治的94例多发性EMP患者, 按随机数字表法分为宫腔镜下电刀切除术(HER)组和HCKR组, 每组47例。HER组采用宫腔负压吸引术联合HER治疗, HCKR组采用宫腔负压吸引术联合HCKR治疗。对比两组围术期指标、子宫内膜血流参数[阻力指数(RI)、搏动指数(PI)]、术后并发症发生率、术后1年复发率和妊娠率。结果 HCKR组手术时间、住院天数短于HER组, 术中出血量、膨宫液吸收量少于HER组(P<0.05);术后3个月, HCKR组RI、PI低于HER组(P<0.05);HCKR组术后并发症发生率(6.38%, 3/47)低于HER组(21.28%, 10/47), P<0.05;HCKR组术后1年复发率(8.51%, 4/47)低于HER组(27.66%, 13/47), 妊娠率(42.55%, 20/47)高于HER组(10.64%, 5/47), P<0.05。结论宫腔负压吸引术联合HCKR治疗多发性EMP效果显著, 能降低出血量和膨宫液吸收量, 缩短手术时间和住院天数, 改善子宫内膜血流参数, 且并发症发生率和复发率低, 有利于促进妊娠。

关键词：多发性子宫内膜息肉宫腔负压吸引术宫腔镜冷刀切除术炎症因子