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A small electron beam ion trap/source facility for electron/neutral-ion collisional spectroscopy in astrophysical plasmas

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Research in Astronomy and Astrophysics 2018年第1期18卷 1-10页

作者： Gui-Yun Liang Hui-Gang Wei Da-Wei Yuan Fei-Lu Wang Ji-Min Peng jia-yong zhong Xiao-Long Zhu Mike Schmidt Günter Zschornack Xin-Wen Ma Gang Zhao Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Department of Astronomy Beijing Normal University Beijing 100875 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China DREEBIT GmbH 01109 Dresden Germany

Spectra are fundamental observation data used for astronomical research,but understanding them strongly depends on theoretical models with many fundamental parameters from theoretical *** models give different insights for understanding a specific ***,laboratory benchmarks for these theoretical models become *** electron beam ion trap is an ideal facility for spectroscopic benchmarks due to its similar conditions of electron density and temperature compared to astrophysical plasmas in stellar coronae,supernova remnants and so *** this paper,we will describe the performance of a small electron beam ion trap/source facility installed at National Astronomical Observatories,Chinese Academy of *** present some preliminary experimental results on X-ray emission,ion production,the ionization process of trapped ions as well as the effects of charge exchange on the ionization.

关键词： X-ray:general atomic processes line:formation method:laboratory:atomic

Probing the peripheral self-generated magnetic field distribution in laser-plasma magnetic reconnection with Martin-Puplett interferometer polarimeter

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Chinese Physics B 2024年第4期33卷 129-134页

作者：张雅芃姚嘉文刘正东马作霖仲佳勇 Department of Astronomy Beijing Normal UniversityBeijing 100875China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China

Magnetic reconnection of the self-generated magnetic fields in laser-plasma interaction is an important laboratory method for modeling high-energy density astronomical and astrophysical *** use the Martin-Puplett interferometer(MPI)polarimeter to probe the peripheral magnetic fields generated in the common magnetic reconnection configuration,two separated coplanar plane targets,in laser-target *** introduce a new method that can obtain polarization information from the interference pattern instead of the sinusoidal function fitting of the intensity.A bidirectional magnetic field is observed from the side view,which is consistent with the magneto-hydro-dynamical(MHD)simulation results of self-generated magnetic field *** find that the cancellation of reverse magnetic fields after averaging and integration along the observing direction could reduce the magnetic field strength by one to two orders of *** indicates that imaging resolution can significantly affect the accuracy of measured magnetic field strength.

关键词： laser-plasma experiment polarimeter self-generated magnetic field magnetic reconnection

Calculation of valence band structures of InAs/GaAs quantum ring and quantum dot:using numerical Fourier transform method

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 106-110页

作者： jia Bo-yong,YU zhong-yuan,LIU Yu-min,TIAN Hong-da Key Laboratory of Information Photonics and Optical Communications,Ministry of Education,Beijing University of Posts and Telecommunications,Beijing 100876,China Key Laboratory of Information Photonics and Optical Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

This article puts forward a new method in calculating the band structures of low-dimensional semiconductor structures. In this study, the valence band structures of InAs/GaAs quantum ring and lens-shaped quantum dot are calculated with four-band model, in the framework of effective-mass envelope function theory. To determine the Hamiltonian matrix elements, this article develops the numerical Fourier transform method instead of the widely used analytical integral method. The valence band mixing is considered. The hole energy levels change dramatically with the geometrical parameters of the quantum ring and quantum dot. It is demonstrated that numerical Fourier transform method can be adopted in low-dimensional structures with any shape. The results of Fourier transform method are consistent with the ones of analytical integral in literature; and they are helpful for studying and fabricating optoelectronic devices.

关键词： valence band structures quantum ring quantum dot numerical Fourier transform

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie jia-Lin Li Ling Gong Xiang-Li zhong Hong-jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： yong Hou Shuo Zhang Jie Dang jia Guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Laboratory astrophysics with laser-driven strong magnetic fields in China

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High Power Laser Science and Engineering 2016年第3期4卷 67-70页

作者： Fei-Lu Wang Xiao-Xing Pei Bo Han Hui-Gang Wei Da-Wei Yuan Gui-Yun Liang Gang Zhao jia-yong zhong Zhe Zhang Bao-Jun Zhu Yan-Fei Li Fang Li Yu-Tong Li Si-Liang Zeng Shi-Yang Zou Jie Zhang Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Astronomy Beijing Normal University Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Institute of Applied Physics and Computational Mathematics Shanghai jiao Tong University

In this paper, the recent studies of laboratory astrophysics with strong magnetic fields in China have been *** the Shenguang-II laser facility of the National Laboratory on High-Power Lasers and Physics, a laser-driven strong magnetic field up to 200 T has been achieved. The experiment was performed to model the interaction of solar wind with dayside magnetosphere. Also the low beta plasma magnetic reconnection(MR) has been studied. Theoretically, the model has been developed to deal with the atomic structures and processes in strong magnetic field. Also the study of shock wave generation in the magnetized counter-streaming plasmas is introduced.

关键词： Laboratory astrophysics laser strong magnetic fields

Structural designs and mechanism insights into electrocatalytic oxidation of 5-hydroxymethylfurfural

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Journal of Energy Chemistry 2025年第1期100卷 792-814页

作者： Jing Lei Huijie Zhang jian Yang jia Ran Jiqiang Ning Haiyan Wang yong Hu Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Department of Chemistry Zhejiang Normal University Jinhua Advanced Research Institute Department of Optical Science and Engineering Fudan University College of Chemistry and Materials Engineering Zhejiang A&F University

Biomass conversion offers an efficient approach to alleviate the energy and environmental *** oxidation of 5-hydroxymethylfurfural(HMF) has attracted tremendous attention in the latest few years for the mild synthesis conditions and high conversion efficiency to obtain 2,5-furan dicarboxylic acid(FDCA), but there still remain problems such as limited yield, short cycle life,and ambiguous reaction mechanism. Despite many reviews highlighting a variety of electrocatalysts for electrochemical oxidation of HMF, a detailed discussion of the structural modulation of catalyst and the underlying catalytic mechanism is still lacking. We herein provide a comprehensive summary of the recent development of electrochemical oxidation of HMF to FDCA, particularly focusing on the mechanism studies as well as the advanced strategies developed to regulate the structure and optimize the performance of the electrocatalysts, including heterointerface construction, defect engineering,single-atom engineering, and in situ reconstruction. Experimental characterization techniques and theoretical calculation methods for mechanism and active site studies are elaborated, and challenges and future directions of electrochemical oxidation of HMF are also prospected. This review will provide guidance for designing advanced catalysts and deepening the understanding of the reaction mechanism beneath electrochemical oxidation of HMF to FDCA.

关键词： Structural design

硼酸镁过饱和水溶液稀释和酸化过程中的Raman光谱

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无机化学学报 2001年第3期17卷 383-387页

作者：贾永忠高世扬夏树屏周园中国科学院青海盐湖研究所西宁810008

用纯水和恒沸点盐酸对六硼酸镁过饱和水溶液进行稀释和酸化，使用激光Ｒａｍａｎ光谱记录反应过程。对光谱峰进行归属。讨论了溶液中含硼量和ｐＨ值对硼氧配阴离子存在形式的影响，对多聚硼氧配阴离子在溶液中的存在形式及其相互作用机... 详细信息

用纯水和恒沸点盐酸对六硼酸镁过饱和水溶液进行稀释和酸化，使用激光Ｒａｍａｎ光谱记录反应过程。对光谱峰进行归属。讨论了溶液中含硼量和ｐＨ值对硼氧配阴离子存在形式的影响，对多聚硼氧配阴离子在溶液中的存在形式及其相互作用机理进行了初步探讨。

关键词： Raman光谱硼酸镁过饱和水溶液多聚硼氧配阴离子稀释酸化结构化学

安培瓶中水蒸汽对量热法测定纯物质热化学性质的影响

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化学研究与应用 2000年第5期12卷 566-568页

作者：景燕贾永忠中国科学院盐湖研究所青海西宁810008

The evaporation heat of H 2O in ampoule was *** influence on the enthalpy of solution of compound was *** method of calibration was given in detail in addition to description and discussion.

关键词：热化学纯物质热化学性质量热法热量计