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Chinese Chemical Letters 2009年第3期20卷 275-278页

作者： Feng Ping Yi Hai yang sun Xian Hua Pan Yuan Xu Ji Zong Li School of Perfume and Aroma Technology Shanghai Institute of Technology Shanghai 200235 China College of Food Science & Technology Shanghai Ocean University Shanghai 201306 China Shanghai Technological and Industrial Promotion Center of Traditional Chinese Medicine Shanghai 201203 China

Fischer indole cyclization of phenylhydrazine and various ketones using carboxyl-functionalized ionic liquid, 1-carboxymethyl- 3-methylimidazolium tetrafluoroborate （abbreviated as [crnmim] [BF4]） as catalyst was successfully performed. The yields of the target compounds were 80-92%, the purities were 96-98%. The catalyst could be recovered and reused for at least six times without significant loss in activity.

关键词： Functionalized ionic liquid Catalyst Fischer indole synthesis

Revisiting the effect of molybdenum on pitting resistance of stainless steels

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Tungsten 2021年第3期3卷 329-337页

作者： yang-Ting sun Xin Tan Long-Lin Lei Jin Li Yi-Ming Jiang Department of Materials Science Fudan UniversityShanghai 200433China

As an important alloyed element to improve the localized corrosion resistance of stainless steels,Mo has been widely studied by *** article reviews the mechanisms of the effect of Mo on localized *** possible effects and corresponding experimental research are described respectively:Mo exists in the passive film as oxide and enhances the film stability(manifesting as lower nucleation probability of localized corrosion and longer delay time of breakdown of the passive film);Mo affects dissolution kinetics and inhibits active dissolution current density(manifesting as smaller metastable pitting current density and size).Then some contradictory results are discussed by considering the pitting model *** speaking,none of the existing experimental results can deny the effect of Mo on the passive film or on the dissolution *** is reasonable to believe that Mo affects the entire process of localized corrosion rather than a single ***,some possible research suggestions are put forward.

关键词： Pitting Molybdenum Stainless steels Localized corrosion

Electrodeposition of rare refractory metals in low-temperature ionic liquids

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Rare Metals 2024年第10期43卷 4921-4933页

作者： Lin-Lin Wang Han-Dong Jiao Rui Yuan Le-yang Li Man-Peng Lin Rui-yang sun Jiu-San Xiao Shu-Qiang Jiao Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Rare refractory metals(RRMs)play a significant role in fundamental industries,including electronics,chemical industry,machinery,etc.,and future advanced fields,such as aerospace and ***,the traditional production processes of RRMs based on high-temperature thermal reduction cannot meet the requirements of low-energy *** dilemma could be addressed efficiently by using a low-temperature electrodeposition strategy in ionic liquids(ILs).This review summarizes a panoramic view of the latest developments on the electrodeposition of RRMs in ILs after a brief review on the current industrial production methods of *** on this,the electrochemical mechanism occurring at the cathode during the electrodeposition process of RRMs in different electrolytes and under different conditions is thoroughly discussed,because it is crucial for the successful production of pure *** addition,this review not only analyses the main challenges that hinder the industrial application of the electrodeposition of RRMs in ILs,but also proposes corresponding *** hope this review can provide a valuable guidance for the fundamental research and industrial development of lowtemperature electrodeposition of RRMs.

关键词： Rare refractory metals Ionic liquids Electrodeposition Production process

Melting temperature of iron under the Earth’s inner core condition from deep machine learning

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Geoscience Frontiers 2024年第6期15卷 485-493页

作者： Fulun Wu Shunqing Wu Cai-Zhuang Wang Kai-Ming Ho Renata M.Wentzcovitch yang sun Department of Physics Xiamen UniversityXiamen 361005China Department of Physics Iowa State UniversityAmesIA 50011USA Department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkNY 10027USA Department of Earth and Environmental Sciences Columbia UniversityNew YorkNY 10027USA Lamont–Doherty Earth Observatory Columbia UniversityPalisadesNY 10964USA

Constraining the melting temperature of iron under Earth’s inner core conditions is crucial for understanding core dynamics and planetary ***,we develop a deep potential(DP)model for iron that explicitly incorporates electronic entropy contributions governing thermodynamics under Earth’s core *** benchmarking demonstrates the DP’s high fidelity across relevant iron phases and extreme pressure and temperature *** thermodynamic integration and direct solid–liquid coexistence simulations,the DP predicts melting temperatures for iron at the inner core boundary,consistent with previous ab initio *** resolves the previous discrepancy of iron’s melting temperature at ICB between the DP model and ab initio calculation and suggests the crucial contribution of electronic *** work provides insights into machine learning melting behavior of iron under core conditions and provides the basis for future development of binary or ternary DP models for iron and other elements in the core.

关键词： Inner core boundary Melting temperature Machine learning Solid-liquid coexistence Free energy calculation Molecular dynamics simulation

Nicotine protects against ulcerative colitis through regulating microRNA-124 and STAT3

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中国药理学与毒理学杂志 2017年第10期31卷 998-999页

作者： Zhen QIN yang sun Ding-feng SU Xia LIU Department of Pharmacology Second Military Medical University

OBJECTIVE Although it is generally believed that nicotine accounts for the beneficial effect of smoking on ulcerative colitis,the underlying mechanisms remain not *** previous finding that nicotine inhibits inflammatory responses through inducing miRNA-124 prompted us to ask whether the miRNA is involved in the protective action of nicotine on *** Mi R-124 expression in colon tissues and cells was determined by q-PCR and in situ *** effect of miR-124 on protective role of nicotine in ulcerative colitis was evaluated in DSS-treated mice and IL-6-treated Caco-2 colon epithelial *** of p-STAT3/STAT3 was detected by immunohistochemistry and Western blot *** miR-124 expression is upregulated in colon tissues from patients and DSS-induced *** treatment further elevated miR-124 level in colon tissues of the mice,in infiltrated lymphocytes and epithelial cells,and augmented miR-124 expression in lymphocytes isolated from human ulcerative colon *** of nicotine also reduced weight loss,improved DAI and decreased HE score in DSS-induced ***,knockdown of miR-124 in vivo significantly diminished the beneficial effect of nicotine,and in vitro on IL-6-treated Caco-2 colon epithelial *** analysis indicated that nicotine inhibited STAT3 activation in vivo and in IL-6-treated Caco-2 colon epithelial cells and Jurkat human T lymphocytes,in whichmiR-124 knockdown led to increased activation of *** These data indicated that nicotine exerts its protective action in UC through inducing miR-124 and its effect on STAT3,suggesting that the miR-124/STAT3 system is a potential target for the therapeutic intervention of UC.

关键词： microRNA-124 nicotine ulcerative colitis p-STAT3 human T lymphocytes colon epithelial cell

Development and application of the new BPM system data processing program at Hefei light source

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Nuclear Science and Techniques 2012年第5期23卷 261-266页

作者： MA Tianji yang Yongliang sun Baogen ZOU Junying LU Ping ZHOU Zeran XU Hongliang NSRL School of Nuclear Science and Technology University of Science and Technology of China Hefei 230029 China

A data processing program has been applied for the new beam position monitor (BPM) system of the storage ring at Hefei Light Source (HLS). The new BPM system in the upgrade project will be equipped with Libera Brilliance BPM processors to replace the old Bergoz MX-BPM processors. The embedded Linux system on Libera has completed some important work, including instrument status check,data acquisition, position calculation, EPICS IOC data release,and so on. A new EPICS record type has been developed to recalculate the beam position with log-ratio method. The property of the new position data was analyzed in the time and frequency domain. The results show that the rms value of beam position measurement resolution can be up to submicron. Preliminary studies have been carried out on the measurement of the tune and the beam lifetime with this new BPM system.

关键词：数据处理程序 PM系统合肥光源嵌入式Linux系统 EPICS 应用开发位置数据

Real-Time Observation on Water-Soluble Ions of PM_(2.5)in Beijing under the Influences of Different Air Masses in Summer

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Atmospheric and Oceanic Science Letters 2014年第1期7卷 23-27页

作者： CHENG Meng-Tian sun yang ZHU Xiao-Wan CHAO Na State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC) Institute of Atmospheric PhysicsChinese Academy of Sciences

To further understand the variations of water-soluble ions in PM2.5 in Beijing,the authors observed their concentrations continuously and in high temporal resolution by the system for rapid collection of fine particles and ion chromatography(RCFP-IC) during 12–18 July *** results combined with those of earlier backward trajectory research are used analyzed to determine the causes of concentration changes in water-soluble ions under the influences of two kinds of air masses in *** results indicate that concentrations of NO3-,SO42-,and NH4+ were influenced strongly by the continental air mass than by the marine air ***- and Na+ were not changed *** the sources of K+,Mg2+,and Ca2+ are mainly concentrated on land,their concentration levels were slightly higher under the control of continental air mass than that of the marine air *** of NO2- during the observation differed from those of other ions;its concentration was significantly higher under the influence of marine air ***,the authors obtain the diurnal variations of eight water-soluble inorganic ions including NH4+,K+,Mg2+,Ca2+,Cl-,NO2-,NO3-,and SO42-.Diurnal variations of NH4+,NO3-,and Cl- showed single peak,which appeared before noon,while SO42- showed two peaks that appeared during rush *** of Mg2+,Ca2+,and K+ showed single peak that appeared in the *** of NO2- showed with a peak appearing at sunrise and a valley appearing at sunset.

关键词： aerosol water-soluble ions PM2.5 summer Beijing

High-temperature oxidation mechanism of ZrCoSb-based half-Heusler thermoelectric compounds

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Journal of Materials Science & Technology 2023年第17期148卷 242-249页

作者： Jinyu Gu Lei Wang Qingfeng Song Chao Wang Xugui Xia Jincheng Liao Yi-yang sun Lidong Chen Shengqiang Bai State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

ZrCoSb-based half-Heusler(HH)compounds are among the most promising thermoelectric(TE)materials for high-temperature power *** resistance is one of the key issues for realizing the practical application of TE materials for long-term service in the ambient working *** this work,the oxidation behavior of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)(ZHCSS)half-Heusler is systematically studied in the service temperature range from 873 to 1073 *** is revealed that three typical layers of oxidation products tend to form on the surface of HH sample,namely,the dense oxide layer(DOL)composed of(Zr,Hf)O_(2) and CoSb,the alternate oxide layer(AOL)composed of repeated(Zr,Hf)O_(2) and CoSb_(2)O_(6)/Co_(3)O_(4),and the CoSb layer between the DOL and *** mass gain during oxidation is mainly caused by the rapid growth of AOL,which is controlled by the outward diffusion of Zr/Hf and the inward diffusion of *** formation of a continuous CoSb layer and DOL is found beneficial to block the outward diffusion of Zr/*** on the analysis of the dominant factors on the outward and inward diffusions as well as the reaction activation energy,a simple approach is proposed to improve the oxidation resistance of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)by pre-oxidizing the sample in low oxygen pressure to form the dense(Zr,Hf)O_(2) and CoSb layers as oxidation protecting and/or diffusion blocking *** oxidation test shows the effectiveness of such pre-oxidation on the formation and growth of the AOL and therefore on improving the service stability of Zr_(0.5)Hf_(0.5)CoSb_(0.8)Sn_(0.2)at high temperatures in the air.

关键词： Thermoelectric Half-Heusler compounds Oxidation mechanism

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从掌心加速器到大科学装置

科学通报 2020年第35期65卷 4007-4012页

作者：孙扬上海交通大学物理与天文学院上海200240

"大科学装置"的概念由发明第一台回旋加速器的欧内斯特·劳伦斯(Ernest Lawrence)提出.从20世纪30年代开始,由于对建造更大加速器的财政需求很高,劳伦斯意识到未来科学技术上的进步必须依托政府支持下的大型科技平台.通过第二次世界大... 详细信息

"大科学装置"的概念由发明第一台回旋加速器的欧内斯特·劳伦斯(Ernest Lawrence)提出.从20世纪30年代开始,由于对建造更大加速器的财政需求很高,劳伦斯意识到未来科学技术上的进步必须依托政府支持下的大型科技平台.通过第二次世界大战期间曼哈顿计划的实施,美国从中直接受益的是当时留下的几处设施在战后全部成为国家实验室.

关键词：回旋加速器大科学装置曼哈顿计划欧内斯特科技平台实验室

Long-lasting,reinforced electrical networking in a high-loading Li_(2)S cathode for high-performance lithium–sulfur batteries

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Carbon Energy 2023年第8期5卷 1-14页

作者： Hun Kim Kyeong-Jun Min Sangin Bang Jang-Yeon Hwang Jung Ho Kim Chong SYoon yang-Kook sun Department of Energy Engineering Hanyang UniversitySeoulRepublic of Korea Department of Materials Science and Engineering Chonnam National UniversityGwangjuRepublic of Korea Institute for Superconducting&Electronic Materials(ISEM) Australian Institute of Innovative Materials(AIIM)University of WollongongNew South WalesNorth WollongongAustralia Department of Materials Science and Engineering Hanyang UniversitySeoulRepublic of Korea

Realizing a lithium sulfide(Li_(2)S)cathode with both high energy density and a long lifespan requires an innovative cathode design that maximizes electrochemical performance and resists electrode ***,a high-loading Li_(2)S-based cathode with micrometric Li_(2)S particles composed of two-dimensional graphene(Gr)and one-dimensional carbon nanotubes(CNTs)in a compact geometry is developed,and the role of CNTs in stable cycling of high-capacity Li–S batteries is *** a dimensionally combined carbon matrix,CNTs embedded within the Gr sheets create robust and sustainable electron diffusion pathways while suppressing the passivation of the active carbon *** a unique point,during the first charging process,the proposed cathode is fully activated through the direct conversion of Li_(2)S into S_(8) without inducing lithium polysulfide *** direct conversion of Li_(2)S into S_(8) in the composite cathode is ubiquitously investigated using the combined study of in situ Raman spectroscopy,in situ optical microscopy,and cryogenic transmission electron *** composite cathode demonstrates unprecedented electrochemical properties even with a high Li_(2)S loading of 10 mg cm^(–2);in particular,the practical and safe Li–S full cell coupled with a graphite anode shows ultra-long-term cycling stability over 800 cycles.

关键词： carbon nanotubes electrical network high energy high loading Li_(2)S cathode lithium-sulfur batteries