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Formation and capturing of nanoparticles in Cu-1wt.%Fe alloy melt during directional solidification process

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Journal of Iron and Steel Research International 2017年第4期24卷 411-415页

作者： Tao Wang Xiao-hua Chen guo-dong shi Chang-rong Li Zi-dong Wang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

A single crystal Cu-1wt.%Fe alloy with finely dispersed iron-rich nanoparticles which keep coherent interface with the copper matrix was prepared under directional *** of nanoparticles in the alloy melt was investigated by performing differential scanning calorimeter tests and designed water quenching experiment at a certain *** show that iron-rich nanoparticles are formed in the Cu-1wt.%Fe alloy melt before primaryα-Cu forms,which is not consistent with equilibrium phase *** that iron-rich nanoparticles are uniformly captured in the matrix was described,which is that numerous nanoparticles follow Brownian motions and are engulfed in the solidified matrix which makes it possible to form uniformly distributed nanoparticles reinforced single crystal Cu-1wt.%Fe alloy.

关键词： Single crystal Copper alloy Nanoparticle Coherent interface Brownian motion

Study on the Comprehensive Assessment for the Large-Scale Water Diversion Project Construction of Wanjiazhai Impact on Ecological Environment Quality

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Systems Science and Systems Engineering 1999年第4期9卷 49-55页

作者： YANG guo\|dong,\ shi Xiao\|feng,\ LIANG Jia\|huaDepartment of Environmental Science, Shanxi University Taiyuan 030006,China

The South Mains Project of Wanjiazhai Yellow River Water Diversion Project, which makes diverted water of the Yellow river accessible to Taiyuan city, is a large scale and key water diversion project providing municipal water supply for Taiyuan. On the basis of surveying ecological environment and social economic environment of the general mains and the south mains, with a total length of 220km, and analyzing surface run off loss of water and soil, the covering rates of vegetation, animal kinds and other main ecological factors, combined construction scales and properties of diversion water project, calculated the ecological value of different zones using the Euclidean distance and gave the comprehensive assessment to existing ecological environmental quality. Finally, ecological environmental problems caused by project construction activities were discussed.

关键词： water diversion project ecological zonations Euclidean distance ecological value comprehensive assessment

Low-temperature chlorination roasting technology for the simultaneous recovery of valuable metals from spent LiCoO_(2)cathode material

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 80-91页

作者： Junjie shi Changle Hou Jingjing dong dong Chen Jianzhong Li Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

With the continuous increase in the disposal volume of spent lithium-ion batteries(LIBs),properly recycling spent LIBs has become essential for the advancement of the circular *** study presents a systematic analysis of the chlorination roasting kinetics and proposes a new two-step chlorination roasting process that integrates thermodynamics for the recycling of LIB cathode *** activation energy for the chloride reaction was 88.41 kJ/mol according to thermogravimetric analysis–derivative thermogravimetry data obtained by using model-free,model-fitting,and Z(α)function(αis conversion rate).Results indicated that the reaction was dominated by the first-order(F1)model when the conversion rate was less than or equal to 0.5 and shifted to the second-order(F2)model when the conversion rate exceeded *** conditions were determined by thoroughly investigating the effects of roasting temperature,roasting time,and the mass ratio of NH_(4)Cl to LiCoO_(2).Under the optimal conditions,namely 400℃,20 min,and NH_(4)Cl/LiCoO_(2)mass ratio of 3:1,the leaching efficiency of Li and Co reached 99.43% and 99.05%,*** of the roasted products revealed that valuable metals in LiCoO_(2)transformed into CoCl_(2) and ***,the reaction mechanism was elucidated,providing insights for the establishment of a novel low-temperature chlorination roasting technology based on a crystal structure *** technology can guide the development of LIB recycling processes with low energy consumption,low secondary pollution,high recovery efficiency,and high added value.

关键词： spent lithium-ion battery thermodynamics chlorination roasting kinetics circular economy

Clinical study of arterial anatomic variations for transradial coronary procedure in Chinese population

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Chinese Medical Journal 2009年第18期122卷 2097-2102页

作者： NIE Bin ZHOU Yu-jie LI guo-zhong shi dong-mei WANG Jian-long Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Background The radial artery is currently regarded as a useful approach for coronary intervention procedures. Adequate anatomical information of the radial artery should be helpful in performing transradial coronary procedures. Few data about the Chinese population have been obtained in this field. Therefore, we tried to evaluate the incidence and clinical significance of anomalous patterns, and their influence on the intervention procedure. Methods In an estimated sample of 3000 cases, radial artery and subclavical artery angiography were performed after insertion of the sheath and coronary angiography （CA）. The evaluable data including branch anomaly, tortuosity of the radial artery and procedural characteristics were analyzed. The procedure success was defined as CA or percutaneous coronary intervention （PCI） completed with the initial radial artery approach without changing to other routes. Results In this study, 1897 cases of CA was undertaken and 1103 cases of CA combined with PCI were performed. The success rate of transradial intervention （TRI） was 96.6% （2899/3000）. The approach in 44 cases was changed to the contralateral radial artery and 57 cases were changed to the brachial artery or femoral artery due to failure with the initial radial artery approach. The angiography of the upper limb artery was performed in all cases. Anatomic variations of upper limb arteries were noted in 610 patients （20.3%）, which included tortuous configurations of the radial artery （5.0%）, hypoplasias （2.2%）, radioulnar loop （1.1%）, abnormal origin of the radial artery （7.7%）, stenosis of radial artery （1.4%）, a tortuous configuration of the brachial artery （0.9%）, a tortuous configurations of the subclavian artery （1.9%）, lusoria subclavian artery （0.1%）, and subclavian artery occlusion （0.03%）. The procedural success rate in the normal population was higher than in the variation group （97.6% vs 93.0%, P 〈0.001）. In addition, other procedural outcomes and incidence of complica

关键词： transradial approach coronao, angioplasty transradial angiography anatomic variation

Dynamics and Operation-State Estimation of Current-Mode Controlled Flyback Converter

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Journal of Electronic Science and Technology 2013年第3期11卷 306-311页

作者： guo-dong shi Qiu-Juan Cao Bo-Cheng Bao Zheng-Hua Ma the School of Information Science and Engineering Changzhou University

By utilizing total magnetic flux φ of the primary and secondary windings of the flyback transformer as a state variable, the discrete-time model of current-mode controlled flyback converter is established, upon which the bifurcation behaviors of the converter are analyzed and two boundary classification equations of the orbit state shifting are obtained. The operation state regions of the current-mode controlled flyback converter are well classified by two boundary classification equations. The theoretical analysis results are verified by power electronics simulator （PSIM）. The estimation of operation-state regions for the flyback converter is useful for the design of circuit parameters, stability control of chaos, and chaos-based applications.

关键词： Index Terms Bifurcation chaos discrete-timemodel flyback converter.

Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang guo Di Lan Zirui Jia Zhenguo Gao Xuetao shi Mukun He Hua guo Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

棚养和塘养甲鱼肌肉中呈味核苷酸的含量变化及比较

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食品研究与开发 2006年第8期27卷 17-22页

作者：方燕过世东江南大学食品学院江苏无锡214036

采用紫外分光光度法和高效液相色谱法,对宰后24h内,甲鱼肌肉中肌酸酐、肌苷酸、肌苷的含量变化进行了定性和定量测定。结果表明:紫外分光光度法定性测定,甲鱼肌肉样品紫外吸收比(260/250)在8h后显著降低,肌肉代谢生成呈味肌苷酸、无味... 详细信息

采用紫外分光光度法和高效液相色谱法,对宰后24h内,甲鱼肌肉中肌酸酐、肌苷酸、肌苷的含量变化进行了定性和定量测定。结果表明:紫外分光光度法定性测定,甲鱼肌肉样品紫外吸收比(260/250)在8h后显著降低,肌肉代谢生成呈味肌苷酸、无味肌苷及苦味次黄嘌呤的总量显著增加;高效液相色谱法定量测定,肌苷的含量在8h后显著增加,肌苷酸含量在宰后24h内逐渐增加;高效液相色谱法定量结果验证了紫外分光光度法定性结果的可靠性。根据宰后肌苷酸等含量变化规律,进一步对宰后于5℃下冷藏12h,棚养、塘养1年、塘养2年甲鱼肌肉中肌酸酐、鸟苷酸、肌苷、肌苷酸含量进行定量测定。结果显示:棚养、塘养1年、塘养2年甲鱼肌肉肌苷酸含量分别为0.0512mg/g、0.1272mg/g、0.2011mg/g,鸟苷酸含量分别为0.0165mg/g、0.0132mg/g、0.0192mg/g。棚养甲鱼鲜味核苷酸含量显著低于塘养甲鱼的含量。

关键词：甲鱼呈味核苷酸高效液相紫外吸收比(260/250)

cis-[PtDMBA(ClCH_2CO_2)_2]晶体双相角结构不变量的符号分布

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物理学报 1990年第7期39卷 1174-1178页

作者：郭东耀郭石杉吉林大学理论化学研究所长春130023

本文计算了cis-[PtDMBA(ClCH_2CO_2)2]晶体的双相角结构不变量ψ_2=ψ_H+ψ_H,统计了其值为负时ψ_2随E的分布情况。对该晶体的计算结果表明,对于具有实际意义的较大E值的ψ,都能用Hauptman概率式给出可靠的符号估计。五个柯卡因及其衍... 详细信息

本文计算了cis-[PtDMBA(ClCH_2CO_2)2]晶体的双相角结构不变量ψ_2=ψ_H+ψ_H,统计了其值为负时ψ_2随E的分布情况。对该晶体的计算结果表明,对于具有实际意义的较大E值的ψ,都能用Hauptman概率式给出可靠的符号估计。五个柯卡因及其衍生物晶体的结果也支持这一结论。

关键词：晶体双相角结构不变量符号分布

Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 191-204页

作者： Zizhuang He Lingzi shi Ran Sun Lianfei Ding Mukun He Jiaming Li Hua guo Tiande Gao Panbo Liu School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710129People’s Republic of China School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase ***,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation *** results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial ***,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic ***,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon *** design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption.

关键词： Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption