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GROWTH PROCESS OF lOW-TEMPERATURE PlASMA-NITRIDING lAYER ON AUSTENITIC STAINlESS STEEl

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Acta Metallurgica Sinica(English letters) 2004年第2期17卷 210-214页

作者： Z.W.Yu l.Wang x.l.xu J.B.Qiang DalianMaritimeUniversity Dalian116026China DalianUniversityofTechnology Dalian116026China

The growth process of low-temperaturs plasma-nitriding layer was investigated by scan-ning electron microscopy (SEM) and x-ray diffraction (xRD). The layer is composedof expanded fcc phase (γN), whose lattice parameter of the layer increases with processtime resulting from increasing the nitrogen content. The layer hardness increases grad-ually with nitrogen content. The high slip band density on the layer surface observedin situ by SEM shows that the surface yield occurs when supersaturated nitrogen con-tent in the layer attains to some value, which is also responsible for the increase inlayer hardness.

关键词： austenitic stainless steel plasma nitriding slip band

Novel medium entropy perovskite oxide Sr(FeCoNiMo)_(1/4)O_(3−δ)for zinc-air battery cathode

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Journal of Energy Chemistry 2024年第9期96卷 669-678页

作者： Kaixin li Juntao Gao xu Han Qi Shao Zhe lü School of Physics Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Heilongjiang Provincial Key laboratory of Advanced Quantum Functional Materials and Sensor Components Harbin 150001HeilongjiangChina

It is widely recognized that the development of ZABs is impeded by the kinetic bottleneck of oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).The application of conformational entropy strategy to oxides often involves introducing multiple elements with different properties,thereby providing outstanding bifunctional catalytic activity for OER/***,the possible underlying catalytic pathways and potential interactions between various components are still poorly *** paper presents an excellent medium-entropy perovskite oxide,Sr(FeCoNiMo)_(1/4)O_(3−δ)(lower overpotential of 301 mV at 10 mA cm^(−2)).Zinc-air batteries employing it as a cathode catalyst demonstrate excellent round-trip efficiency(62%).By combining theoretical calculation with experiments,we aim to establish the link between the electronic structure of perovskite oxides with different elemental compositions and their OER *** reveals that the conformational entropy strategy can simultaneously shift the O 2p-band center and metal d-band center of perovskite oxide towards the vicinity of the Fermi energy level,thereby triggering a more favorable lattice oxygen-participated mechanism(lOM)during the OER *** outcomes of this work provide crucial insights into the role of conformational entropy strategies in oxygen catalysis and offer potential avenues for constructing efficient and stable electrocatalysts.

关键词： Sr(FeCoNiMo)_(1/4)O_(3−δ) Bifunctional catalyst Medium entropy lOM Rechargeable zinc-air batteries

在SrTiO3,NdGaO3衬底上生长的HgBa2CaCu2Oy超导薄膜

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低温物理学报 1999年第1期21卷 51-54页

作者：孙云峰郭建栋徐晓林王永忠熊光成北京大学物理系

通过两步法，在ＳｒＴｉＯ３，ＮｄＧａＯ３衬底上制备了ＨｇＢａ２ＣａＣｕ２Ｏｙ高温超导薄膜，Ｘ射线衍射实验结果证明了薄膜是ｃ轴外延生长的．电阻温度测量表明薄膜的超导零电阻转变温度（Ｔｃ）＞１１５Ｋ和临界电流Ｊｃ＞０．... 详细信息

通过两步法，在ＳｒＴｉＯ３，ＮｄＧａＯ３衬底上制备了ＨｇＢａ２ＣａＣｕ２Ｏｙ高温超导薄膜，Ｘ射线衍射实验结果证明了薄膜是ｃ轴外延生长的．电阻温度测量表明薄膜的超导零电阻转变温度（Ｔｃ）＞１１５Ｋ和临界电流Ｊｃ＞０．４ＭＡ／ｃｍ２（７７Ｋ，零磁场），而且重复性很好．扫描电镜实验揭示了薄膜是层状生长的，晶粒是四方形和八角形的，实验证实基于碳酸盐的靶也是适合于制备汞系铜氧化物高温超导膜的

关键词：衬底基片 SrTiO3,NdGaO3 HgBa2CaCu2Oy

Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： Yifu xu Wenjing liu Bing xu Zhifang xu Key laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by *** understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were *** rivers had averaged SO_(4)^(2-)content at 1336μmol/l,over 10times higher than the global *** δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,*** end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate *** isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid *** on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely *** the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier ***,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

Boosting oxygen reduction activity and CO_(2) resistance on bismuth ferrite-based perovskite cathode for low-temperature solid oxide fuel cells below 600℃

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Journal of Energy Chemistry 2024年第3期90卷 600-609,I0013页

作者： Juntao Gao Zhiyun Wei Mengke Yuan Zhe Wang Zhe lü Qiang li lingling xu Bo Wei School of Physics Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Key laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080HeilongjiangChina School of Physics and Electronic Engineering Harbin Normal UniversityHarbin 150025HeilongjiangChina

Developing efficient and stable cathodes for low-temperature solid oxide fuel cells(lT-SOFCs) is of great importance for the practical ***,we propose a series of Sm-modified Bi_(0.7-x)Sm_xSr_(0.3)FeO_(3-δ) perovskites as highly-active catalysts for *** doping can significantly enhance the electrocata lytic activity and chemical stability of *** 600℃,Bi_(0.675)Sm_(0.025)Sr_(0.3)FeO_(3-δ)(BSSF25) cathode has been found to be the optimum composition with a polarization resistance of 0.098 Ω cm^2,which is only around 22.8% of Bi_(0.7)Sr_(0.3)FeO_(3-δ)(BSF).A full cell utilizing BSSF25 displays an exceptional output density of 790 mW cm^(-2),which can operate continuously over100 h without obvious *** remarkable electrochemical performance observed can be attributed to the improved O_(2) transport kinetics,superior surface oxygen adsorption capacity,as well as O_(2)p band centers in close proximity to the Fermi ***,larger average bonding energy(ABE) and the presence of highly acidic Bi,Sm,and Fe ions restrict the adsorption of CO_(2) on the cathode surface,resulting in excellent CO_(2) *** work provides valuable guidance for systematic design of efficient and durable catalysts for lT-SOFCs.

关键词： low-temperature solid oxide fuel cell Perovskite cathode DFT calculations CO_(2) tolerance

Tomographic reconstruction of the Earth’s magnetosheath from multiple spacecraft:a theoretical study

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Earth and Planetary Physics 2024年第1期8卷 204-214页

作者： A.M.Jorgensen TianRan Sun Y.Huang l.li R.xu l.Dai Chi Wang New Mexico Institute of Mining and Technology SocorroNMUSA National Space Science Center Chinese Academy of SciencesBeijing 100190China Tsinghua University Beijing 100084China

Following our earlier work on tomographic reconstruction of the magnetosheath soft x-ray emissions with superposed epoch analysis of many images recorded from a single spacecraft we now explore the instantaneous reconstruction of the magnetosheath and magnetopause using a few images recorded simultaneously from a few *** work is motivated by the prospect of possibly having two or three soft x-ray imagers in space in the coming years,and that many phenomena which occur at the magnetopause boundary,such as reconnection events and pressure pulse responses,do not lend themselves as well to superposed epoch *** the reconstruction is successful-which we demonstrate in this paper that it can be-this collection of imagers can be used to reconstruct the magnetosheath and magnetopause from a single image from each spacecraft,allowing for high time resolution *** this paper we explore the reconstruction using,two,three,and four *** show that the location of the subsolar point of the magnetopause can be determined with just two satellites,and that volume emissions of soft x-rays,and the shape of the boundary,can be reconstructed using three or more satellites.

关键词： magnetosheath tomography soft x-ray imaging SMIlE

Evaluation of the Oxidation Reactivity and Behavior of Exhaust Soot Particles from Diesel Engines with Different Emission levels

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 72-80页

作者： Wang Yajun lin lei xing Jianqiang lüxu Yang He Song Haiqing SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China State Key laboratory of Engines Tianjin UniversityTianjin 300072China

The aim of this study was to investigate the oxidation reactivity and behavior of exhaust particulate matter(PM)from diesel *** samples from two diesel engines(1K,CY4102)with different emission levels were collected by a thermophoretic system and a quartz *** oxidation reactivity,oxidation behaviors,and physicochemical properties of the PM samples were analyzed using thermogravimetric analysis(TGA),high-resolution transmission electron microscopy(HRTEM),Fourier-transform infrared spectrometry(FTIR),and Raman *** results showed that there was a great difference in the oxidation reactivity of soot particles emitted by the two different diesel engines.A qualitative analysis of the factors influencing oxidation reactivity showed that the nanostructure,degree of graphitization,and relative concentration of aliphatic C—H functional groups were the most important factors,whereas no significant correlation was found between the primary particle size and activation energy of the diesel *** on the oxidation behavior analysis,the diesel soot particles exhibited both internal and surface oxidation modes during the oxidation *** oxidation was dominant during the initial stage,and as oxidation progressed,the mode gradually changed to internal *** oxidation mode of soot particles from the 1K engine was significantly higher than that of CY4102.

关键词： diesel engine soot particles oxidation reactivity oxidation behavior

A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

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Journal of Palaeogeography 2024年第1期13卷 149-164页

作者： Da-Wei lü Wen-xu Du Zhi-Hui Zhang Yuan Gao Tian-Tian Wang Jin-Cheng xu Ao-Cong Zhang Cheng-Shan Wang Shandong Provincial Key laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina School of Earth Sciences and Resources China University of GeosciencesBejing 100083China Institute of Earth Sciences China University of Geosciences(Bejing)Beijing 100083China

The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

关键词： Wildfire Cretaceous Atmospheric oxygen Taphonomy Charcoal

STCF conceptual design report (Volume 1): Physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov x.C.Ai l.P.An R.Aliberti Q.An x.Z.Bai Y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko Z.H.Bu F.M.Cai H.Cai J.J.Cao Q.H.Cao x.Cao Z.Cao Q.Chang K.T.Chao D.Y.Chen H.Chen H.x.Chen J.F.Chen K.Chen l.l.Chen P.Chen S.l.Chen S.M.Chen S.Chen S.P.Chen W.Chen x.Chen x.F.Chen x.R.Chen Y.Chen Y.Q.Chen H.Y.Cheng J.Cheng S.Cheng T.G.Cheng J.P.Dai l.Y.Dai x.C.Dai D.Dedovich A.Denig I.Denisenko J.M.Dias D.Z.Ding l.Y.Dong W.H.Dong V.Druzhinin D.S.Du Y.J.Du Z.G.Du l.M.Duan D.Epifanov Y.l.Fan S.S.Fang Z.J.Fang G.Fedotovich C.Q.Feng x.Feng Y.T.Feng J.l.Fu J.Gao Y.N.Gao P.S.Ge C.Q.Geng l.S.Geng A.Gilman l.Gong T.Gong B.Gou W.Gradl J.l.Gu A.Guevara l.C.Gui A.Q.Guo F.K.Guo J.C.Guo J.Guo Y.P.Guo Z.H.Guo A.Guskov K.l.Han l.Han M.Han x.Q.Hao J.B.He S.Q.He x.G.He Y.l.He Z.B.He Z.x.Heng B.l.Hou T.J.Hou Y.R.Hou C.Y.Hu H.M.Hu K.Hu R.J.Hu W.H.Hu x.H.Hu Y.C.Hu J.Hua G.S.Huang J.S.Huang M.Huang Q.Y.Huang W.Q.Huang x.T.Huang x.J.Huang Y.B.Huang Y.S.Huang N.Hüsken V.Ivanov Q.P.Ji J.J.Jia S.Jia Z.K.Jia H.B.Jiang J.Jiang S.Z.Jiang J.B.Jiao Z.Jiao H.J.Jing x.l.Kang x.S.Kang B.C.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin Y.lei E.levichev C.H.li C.li D.Y.li F.li G.li G.li H.B.li H.li H.N.li H.J.li H.l.li J.M.li J.li l.li l.li l.Y.li N.li P.R.li R.H.li S.li T.li W.J.li x.li x.H.li x.Q.li x.H.li Y.li Y.Y.li Z.J.li H.liang J.H.liang Y.T.liang G.R.liao l.Z.liao Y.liao C.x.lin D.x.lin x.S.lin B.J.liu C.W.liu D.liu F.liu G.M.liu H.B.liu J.liu J.J.liu J.B.liu K.liu K.Y.liu K.liu l.liu Q.liu S.B.liu T.liu x.liu Y.W.liu Y.liu Y.l.liu Z.Q.liu Z.Y.liu Z.W.liu I.logashenko Y.long C.G.lu J.x.lu N.lu Q.F.lü Y.lu Y.lu Z.lu P.lukin F.J.luo T.luo x.F.luo Y.H.luo H.J.lyu x.R.lyu J.P.Ma P.Ma Y.Ma Y.M.Ma F.Maas S.Malde D.Matvienko Z.x.Meng R.Mitchell A.Nefediev Y.Nefedov S.l.Olsen Q.Ouyang P.Pakhlov G.Pakhlova x.Pan Y.Pan E.Passemar Y.P.Pei H.P.Peng l.Peng x.Y.Peng x.J.Peng K.Peters S.Pivovarov E.Pyata B.B.Qi Y.Q.Qi W.B.Qian Y.Qian C.F.Qiao J.J.Qin J.J.Qin l.Q.Qin x.S.Qin T.l.Qiu J.Rademacker C.F.Redmer H.Y.Sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear Physics Novosibirsk 630090Russia CAS Key laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Cavendish laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom Central China Normal University Wuhan 430079China Central South University Changsha 410083China China University of Geosciences Wuhan 430074China China University of Mining and Technology Xuzhou 221116China École Polytechnique Fédérale de lausanne(EPFl) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China Hangzhou Institute for Advanced Study UCASHangzhou 310024China Hebei Normal University Shijiazhuang 050024China Hebei University Baoding 071002China Hefei University of Technology Hefei 230601China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China High Energy Physics Center Chung-Ang UniversitySeoul 06974Korea Higher School of Economy 11 Pokrovsky Bulvar Moscow 109028Russia Huangshan University Huangshan 245000China Hubei University of Automotive Technology Shiyan 442002China Hunan Normal University Changsha 410081China Hunan University of Science and Technology Xiangtan 411201China Hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced Science Facilities Shenzhen 518107China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Jilin University Changch

The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard *** STCF project in China is under development with an extensive R&D *** document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity STCF detector conceptual design