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Influence of crucible material on inclusions in 95Cr saw-wire steel deoxidized by Si–Mn

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1083-1099页

作者： Yang Li Chang-yong chen Guo-qing Qin Zhou-hua jiang Meng Sun Kui chen School of Metallurgy Northeasten UniversityShenyang 110819China

To investigate the interaction mechanism between 95 Cr saw-wire steel and different refractories,we conducted laboratory experiments at 1873 *** crucible materials(SiO2,Al2 O3,MgO·Al2 O3,MgO,and MgO-CaO)were *** results indicate that SiO2,Al2 O3,and MgO·Al2 O3 are not suitable for smelting low-oxygen,low-[Al]s 95 Cr saw-wire steel,mainly because they react with the elements in the molten steel and pollute the steel *** contrast,MgO-CaO is an ideal choice to produce 95 Cr saw-wire *** offers three advantages:(ⅰ)It does not decompose by itself at the steelmaking temperature of 1873 K because it exhibits good thermal stability;(ⅱ)[C],[Si],and[Mn]in molten steel cannot react with it to increase the[O]content;and(ⅲ)it not only desulfurizes and dephosphorizes but also removes Al2 O3 inclusions from the steel *** a result,the contents of the main elements([C],[Si],[Mn],[Cr],N,T.O(total oxygen))in the steel are not affected and the content of impurity elements([Al]s,P,and S)can be perfectly controlled within the target ***,the number and size of inclusions in the steel samples decrease sharply when the MgO-CaO crucible is used.

关键词： nonmetallic inclusions 95Cr saw-wire steel crucible material MgO–CaO refractory

Emergent Z2 topological invariant and robust helical edge states in two-dimensional topological metals

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Science China(Physics,Mechanics & Astronomy) 2020年第10期63卷 105-110页

作者： Chui-Zhen chen hua jiang Dong-Hui Xu X.C.Xie Institute for Advanced Study and School of Physical Science and Technology Soochow UniversitySuzhou 215006China Department of Physics Hubei UniversityWuhan 430062China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China Beijing Academy of Quantum Information Sciences Beijing 100193China

In this work,we study the effects of disorder on topological metals that support a pair of helical edge modes deeply embedded inside the gapless bulk ***,we predict that a quantum spin Hall(QSH)phase can be obtained from such topological metals without opening a global band *** be specific,disorder can lead to a pair of robust helical edge states which is protected by an emergent Z2 topological invariant,giving rise to a quantized conductance plateau in transport *** results are instructive for solving puzzles in various transport experiments on QSH materials that are intrinsically *** work also will inspire experimental realization of the QSH effect in disordered topological metals.

关键词： topological metal disorder Z2 topological invariant

A New Organo-templated Layered Zincophosphate Synthesized from a Solvothermal System Containing Racemic 1,2-Diaminopropane

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Chemical Research in Chinese Universities 2002年第4期18卷 375-379页

作者： chen Wei YUAN Hong-ming jiang Yu-sheng HUO hua chen Jie-sheng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130023P.R.China

A new layered zincophosphate was synthesized under solvothermal conditions by employing racemic 1,2-diaminopropane as the structure-directing agent. The structure of the compound was solved by means of single-crystal X-ray diffraction analysis. It crystallized in the monoclinic space group P2_1/c (No. 14) with a= 1.047 0(3) nm, b=0.787 31(18) nm, c=0.662 68(16) nm, β=103.120(5)°, V=0.532 0(2) nm 3 and Z=4. The structure is made up of anionic zincophosphate sheets stacked in an AAAA sequence. The individual sheet contains three- and four-membered rings and the infinite Zn-O-Zn chains can also be envisaged in the sheet. The charge-balancing diprotonated racemic 1,2-diaminopropane cations are sandwiched between the layers, whereas the inorganic layers are stabilized by strong H-bonds formed between the N atoms of the amine and the O atoms in the inorganic sheets.

关键词： Layered zincophosphate X-ray diffraction Crystal structure Racemic system

The dynamics beamline at SSRF

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Nuclear Science and Techniques 2024年第9期35卷 56-67页

作者： Zhen Liu Li-hua Wang Yong jiang Ya-Jun Tong hua-Chun Zhu Te Ji Min chen Zheng jiang Xiang-Jun Wei Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China ShanghaiTech University Shanghai 201210China

The dynamics beamline(D-Line),which combines synchrotron radiation infrared spectroscopy(SR-IR)and energy-disper-sive X-ray absorption spectroscopy(ED-XAS),is the first beamline in the world to realize concurrent ED-XAS and SR-IR measurements at the same sample position on a millisecond time-resolved *** combined technique is effective for investigating rapid structural changes in atoms,electrons,and molecules in complicated disorder systems,such as those used in physics,chemistry,materials science,and extreme ***,ED-XAS and SR-IR can be used independently in the two branches of the *** ED-XAS branch is the first ED-XAS beamline in China,which uses a tapered undulator light source and can achieve approximately 2.5×10^(12)photons/s·300 eV BW@7.2 keV at the sample *** exchange-able polychromator operating in the Bragg-reflection or Laue-transmission configuration is used in different energy ranges to satisfy the requirements for beam size and energy *** focused beam size is approximately 3.5μm(H)×21.5μm(V),and the X-ray energy range is 5–25 *** one-and two-dimensional position-sensitive detectors with frame rates of up to 400 kHz enables time resolutions of tens of microseconds to be *** distinctive techniques,such as the concurrent measurement of in situ ED-XAS and infrared spectroscopy,time-resolved ED-XAS,high-pressure ED-XAS,XMCD,and pump-probe ED-XAS,can be applied to achieve different scientific goals.

关键词： ED-XAS SR-IR Time-resolved D-line SSRF

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1-萘酚的太赫兹光谱实验及理论研究

原子与分子物理学报 2025年第4期42卷 33-39页

作者：王利民朱立江孙延华国家能源集团煤焦化有限责任公司乌海016000

1-萘酚是煤化工产物萘的合成产物,对环境和人体健康有危害.采用太赫兹时域光谱(THz-TDS)技术,获得了1-萘酚在0.5~4.0 THz范围内的实测太赫兹吸收谱,同时运用密度泛函理论(DFT)平面波赝势模型对1-萘酚晶胞模型进行理论光谱计算,探讨了平... 详细信息

1-萘酚是煤化工产物萘的合成产物,对环境和人体健康有危害.采用太赫兹时域光谱(THz-TDS)技术,获得了1-萘酚在0.5~4.0 THz范围内的实测太赫兹吸收谱,同时运用密度泛函理论(DFT)平面波赝势模型对1-萘酚晶胞模型进行理论光谱计算,探讨了平面波截断能在800~1600 eV范围内对理论光谱的影响,并对吸收峰的振动模式进行了理论归属.实验结果表明,1-萘酚在0.5~4.0 THz范围内有1.14 THz、1.60 THz、2.16 THz、2.81 THz、3.56 THz共5个吸收峰,平面波截断能1400 eV下得到的理论吸收谱与实测吸收谱在吸收峰个数、峰位、归一化峰强度上均有较好的一致性,5个吸收峰的振动模式均是以两元环为平面的受氢键束缚的面外摇摆振动或者面内扭转振动引起的.这为太赫兹技术对1-萘酚的识别提供了实验和理论基础,具有一定的理论意义和实际应用价值.

关键词：太赫兹密度泛函理论(DFT) 理论光谱 1-萘酚

Einstein Probe discovery of EP240408a: A peculiar X-ray transient with an intermediate timescale

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 222-240页

作者： Wenda Zhang Weimin Yuan Zhixing Ling Yong chen Nanda Rea Arne Rau Zhiming Cai huaqing cheng Francesco Coti Zelati Lixin Dai Jingwei Hu Shumei Jia Chichuan Jin Dongyue Li Paul O’Brien Rongfeng Shen Xinwen Shu Shengli Sun Xiaojin Sun Xiaofeng Wang Lei Yang Bing Zhang chen Zhang Shuang-Nan Zhang Yonghe Zhang Jie An David Buckley Alexis Coleiro Bertrand Cordier Liming Dou Rob Eyles-Ferris Zhou Fan hua Feng Shaoyu Fu Johan P.U.Fynbo Lluis Galbany Saurabh W.Jha Shuaiqing jiang Albert Kong Erik Kuulkers Weihua Lei Wenxiong Li Bifang Liu Mingjun Liu Xing Liu Yuan Liu Zhu Liu Chandreyee Maitra Alessio Marino Itumeleng Monageng Kirpal Nandra Jeremy Sanders Roberto Soria Lian Tao Junfeng Wang Song Wang Tinggui Wang Zhongxiang Wang Qingwen Wu Xuefeng Wu Dong Xu Yanjun Xu Suijian Xue Yongquan Xue Zijian Zhang Zipei Zhu Hu Zou Congying Bao Fansheng chen Houlei chen Tianxiang chen Wei chen Yehai chen Yifan chen chenzhou Cui Weiwei Cui Yanfeng Dai Dongwei Fan Ju Guan Dawei Han Dongjie Hou Haibo Hu Maohai huang Jia Huo Zhenqing Jia Bowen jiang Ge Jin chengkui Li Junfei Li Longhui Li Maoshun Li Wei Li Zhengda Li Tianying Lian Congzhan Liu Heyang Liu huaqiu Liu Fangjun Lu Laidan Luo Jia Ma Xuan Mao Haiwu Pan Xin Pan Liming Song Hui Sun Yunyin Tan Qingjun Tang Yihan Tao Hao Wang Juan Wang Lei Wang Wenxin Wang Yilong Wang Yusa Wang Qinyu Wu Haitao Xu Jingjing Xu Xinpeng Xu Yunfei Xu Zhao Xu Changbin Xue Yulong Xue Ailiang Yan Haonan Yang Xiongtao Yang Yanji Yang Juan Zhang Mo Zhang Wenjie Zhang Zhen Zhang Zhen Zhang Ziliang Zhang Donghua Zhao Haisheng Zhao Xiaofan Zhao Zijian Zhao Hongyan Zhou Yilin Zhou Yuxuan Zhu Zhencai Zhu National Astronomical Observatories Chinese Academy of Sciences School of Astronomy and Space Sciences University of Chinese Academy of Sciences Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Institute of Space Sciences (ICE) CSIC Institut d’Estudis Espacials de Catalunya (IEEC) Max Planck Institute for Extraterrestrial Physics Innovation Academy for Microsatellites Chinese Academy of Sciences Department of Physics University of Hong Kong School of Physics and Astronomy University of Leicester School of Physics and Astronomy Sun Yat-sen University Department of Physics Anhui Normal University Shanghai Institute of Technical Physics Chinese Academy of Sciences Physics Department Tsinghua University Nevada Center for Astrophysics University of Nevada Las Vegas Department of Physics and Astronomy University of Nevada Las Vegas South African Astronomical Observatory Department of Astronomy University of Cape Town Department of Physics University of the Free State Université Paris Cité CNRS Astroparticule et Cosmologie Université Paris Cité CEA Paris-Saclay IRFU/DAp-AIM Department of Astronomy Guangzhou University Cosmic Dawn Center (DAWN) Niels Bohr Institute University of Copenhagen Department of Physics and Astronomy Rutgers the State University of New Jersey Institute for Cosmic Ray Research The University of Tokyo ESA/ESTEC Department of Astronomy School of Physics huazhong University of Science and Technology INAF-Osservatorio Astrofisico di Torino Sydney Institute for Astronomy School of Physics The University of Sydney Department of Astronomy Xiamen University Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University Department of Astronomy University of Science and Technology School of Astronomy and Space Sciences University of Science and Technology of China Institute of Deep Space Sciences Deep Space Exploration Laboratory Department of Astronomy School of Physics and Astronomy Yunnan University Shanghai Astronomical Observatory Chi

We report the discovery of a peculiar X-ray transient,EP240408a,by Einstein Probe （EP） and follow-up studies made with EP,Swift,NICER,GROND,ATCA and other ground-based multiwavelength *** new transient was first detected with Wide-field X-ray Telescope （WXT） on board EP on April 8th,2024,manifested in an intense yet brief X-ray flare lasting for *** flare reached a peak flux of 3.9×10-9erg cm-2s-1in 0.5-4 ke V,～300 times brighter than the underlying X-ray emission detected throughout the *** and more precise follow-up observations by EP/FXT,Swift and NICER confirmed the finding of this new *** X-ray spectrum is non-thermal in 0.5-10 ke V,with a power-law photon index varying *** X-ray light curve shows a plateau lasting for ～4 d,followed by a steep decay till becoming undetectable ～10 d after the initial *** on its temporal property and constraints from previous EP observations,an unusual timescale in the range of 7-23 d is found for EP240408a,which is intermediate between the commonly found fast and long-term *** counterparts have been found in optical and near-infrared,with the earliest observation at 17 h after the initial X-ray detection,suggestive of intrinsically weak emission in these *** demonstrate that the remarkable properties of EP240408a are inconsistent with any of the transient types known so far,by comparison with,in particular,jetted tidal disruption events,gamma-ray bursts,X-ray binaries and fast blue optical *** nature of EP240408a thus remains an *** suggest that EP240408a may represent a new type of transients with intermediate timescales of the order of～10 *** detection and follow-ups of more of such objects are essential for revealing their origin.

关键词： X-ray transients ${\bm~{Einstein~~Probe}}$

Inexact proximal gradient algorithm with random reshuffling for nonsmooth optimization

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Science China(Information Sciences) 2025年第1期 219-237页

作者： Xia jiang Yanyan FANG Xianlin ZENG Jian SUN Jie chen National Key Lab of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center School of Electronic and Information Engineering Tongji University

Proximal gradient algorithms are popularly implemented to achieve convex optimization with nonsmooth regularization. Obtaining the exact solution of the proximal operator for nonsmooth regularization is challenging because errors exist in the computation of the gradient; consequently, the design and application of inexact proximal gradient algorithms have attracted considerable attention from researchers. This paper proposes computationally efficient basic and inexact proximal gradient descent algorithms with random reshuffling. The proposed stochastic algorithms take randomly reshuffled data to perform successive gradient descents and implement only one proximal operator after all data pass through. We prove the convergence results of the proposed proximal gradient algorithms under the sampling-without-replacement reshuffling *** computational errors exist in gradients and proximal operations, the proposed inexact proximal gradient algorithms can converge to an optimal solution neighborhood. Finally, we apply the proposed algorithms to compressed sensing and compare their efficiency with some popular algorithms.

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First-Principles Study on Hexagonal WO_3 for HCHO Gas Sensing Application

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 772-780页

作者： Bo-Lin Tang Guo-hua jiang Wen-Xing chen Jun-Min Wan Department of Materials Engineering Zhejiang Sci-Tech University Key Laboratory of Advanced Textile Materials and Manufacturing Technology (ATMT) Ministry of Education National Engineering Laboratory for Textile Fiber Materials and Processing Technology (Zhejiang)

The adsorption energy, electronic structure, density of states, and electron population for adsorption of HCHO on the hexagonal WO3 （h-WO3）（001） surfaces were investigated by density functional theory calculations. The adsorption energy of HCHO molecule on W and O sites of WO-terminated h-WO3 （001） surface was -0.309 and -0.432 eV compared with the value at -1.936 eV for HCHO molecule on O-terminated h-WO3 （001） surface. According to the calculated results, the adsorption of HCHO on h-WO3 （001） surface was spontaneous with physical adsorption on WO- terminated h-WO3 （001） surface and chemisorption on O-terminated h-WO3 （001） surface. The charge transfer from adsorbed HCHO molecule to WO3 （001） surface was confirmed by the Mulliken population analysis, which suggested the potential application of h-WO3 for HCHO gas detection.

关键词： Semiconductors Surfaces Crystal structure Electronic structure

Effects of N and/or S Doping on Structure and Photocatalytic Properties of BiOBr Crystals

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 460-466页

作者： Guo-hua jiang Xia Li Zhen Wei Teng-Teng jiang Xiang-Xiang Du Wen-Xing chen Key Laboratory of Advanced Textile Materials and Manufacturing Technology (ATMT) Ministry of EducationZhejiang Sci-Tech University Department of Materials Engineering College of Materials and TextileZhejiang Sci-Tech University

The BiOBr crystals doped with N and/or S have been prepared by a facile and rapid solvothermal method using urea and/or thiourea as doped resource. The morphologies and structures of the as-prepared samples were characterized by SEM, TEM, XRD, XPS and PL spectrum. Their electronic structures have been investigated and discussed using first principles based on the density functional theory. The photocatalytic properties of the products can be adjusted by the content and species of dopants.

关键词： Hydrothermal method Photocatalysis Microstructure and properties