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Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

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journal of Iron and Steel Research(International) 2022年第5期29卷 819-835页

作者： j.L.Guo T.j.chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

The effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were *** results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more *** softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface *** vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing *** is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is *** behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

青藏高原及其周边泥盆纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1058-1090页

作者：郄文昆梁昆郭文高彪宋俊俊陈波黄璞乔丽徐洪河陈吉涛孙语聪张以春中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学南京学院南京211135

青藏高原及其周边泥盆系分布广泛、类型多样、化石丰富,记录着北半球古亚洲洋的持续消减和南半球原特提斯洋向古特提斯洋转变的关键过程,对阐明这一时期的全球古地理格局、板块运动和生物多样性变化具有重要意义.南天山(洋)缝合带和龙木... 详细信息

青藏高原及其周边泥盆系分布广泛、类型多样、化石丰富,记录着北半球古亚洲洋的持续消减和南半球原特提斯洋向古特提斯洋转变的关键过程,对阐明这一时期的全球古地理格局、板块运动和生物多样性变化具有重要意义.南天山(洋)缝合带和龙木错-双湖-昌宁-孟连(洋)缝合带两侧的地块分属不同沉积体系和生物古地理区系,指示该洋盆具有显著的构造古地理分隔意义,分别代表了古亚洲洋和古特提斯洋的主支洋盆,以此为界泥盆系可以划分为天山型、特提斯型和冈瓦纳型三种类型.本文主要基于近年来青藏高原及其邻区泥盆纪地层古生物的研究进展,分别提供最新的综合地层格架,并结合沉积物源分析和生物群特征对比进行古地理重建,为探讨青藏高原及其邻区各个块体的早期地质演化及其动力学机制奠定基础.基于碎屑锆石物源分析和生物古地理研究,特提斯喜马拉雅带、保山地块、南羌塘地块、北羌塘地块、思茅地块、腾冲地块和华南板块沉积物源与印度板块具有亲缘性,而拉萨地块与澳大利亚板块具有亲缘性,且可能位于华南板块与澳大利亚板块之间.早泥盆世埃姆斯期,华南板块可能已经从冈瓦纳大陆北缘裂解出来,代表着金沙江-哀牢山洋的打开.中泥盆世,古特提斯洋洋中脊快速扩张,对应着全球海平面上升、碳酸盐岩台地的广泛分布和泥盆纪海水锶同位素的最低值.晚泥盆世古特提斯洋已达到相当规模,最终导致古特提斯缝合带中晚泥盆世放射虫硅质岩大量产出.

关键词：泥盆系古特提斯洋综合地层生物群物源分析古地理

Amplitude analysis of the decays D^(0)→π^(+)π^(−)π^(+)π^(−)and D^(0)→π^(+)π^(−)π^(0)π^(0)

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Chinese Physics C 2024年第8期48卷 6-33页

作者： M.Ablikim M.N.Achasov P.Adlarson O.Afedulidis X.C.Ai R.Aliberti A.Amoroso Q.An Y.Bai O.Bakina I.Balossino Y.Ban H.-R.Bao V.Batozskaya K.Begzsuren N.Berger M.Berlowski M.Bertani D.Bettoni F.Bianchi E.Bianco A.Bortone I.Boyko R.A.Briere A.Brueggemann H.Cai X.Cai A.Calcaterra G.F.Cao N.Cao S.A.Cetin j.F.Chang W.L.Chang G.R.Che G.Chelkov C.chen C.H.chen Chao chen G.chen H.S.chen M.L.chen S.j.chen S.L.chen S.M.chen T.chen X.R.chen X.T.chen Y.B.chen Y.Q.chen Z.j.chen Z.Y.chen S.K.Choi X.Chu G.Cibinetto F.Cossio j.j.Cui H.L.Dai j.P.Dai A.Dbeyssi R.E.de Boer D.Dedovich C.Q.Deng Z.Y.Deng A.Denig I.Denysenko M.Destefanis F.De Mori B.Fang S.S.Fang W.X.Fang Y.Fang Y.Q.Fang R.Farinelli L.Fava F.Feldbauer G.Felici C.Q.Feng j.H.Feng Y.T.Feng K.Fischer M.Fritsch C.D.Fu j.L.Fu Y.W.Fu H.Gao Y.N.Gao Yang Gao S.Garbolino I.Garzia P.T.Ge Z.W.Ge C.Geng E.M.Gersabeck B.Ding X.X.Ding Y.Ding Y.Ding j.Dong L.Y.Dong M.Y.Dong X.Dong M.C.Du S.X.Du Z.H.Duan P.Egorov Y.H.Fan j.Fang jA.Gilman K.Goetzen L.Gong W.X.Gong W.Gradl S.Gramigna M.Greco M.H.Gu Y.T.Gu C.Y.Guan Z.L.Guan A.Q.Guo L.B.Guo M.j.Guo R.P.Guo Y.P.Guo A.Guskov j.Gutierrez K.L.Han T.T.Han X.Q.Hao F.A.Harris K.K.He K.L.He F.H.Heinsius C.H.Heinz Y.K.Heng C.Herold T.Holtmann P.C.Hong G.Y.Hou X.T.Hou Y.R.Hou Z.L.Hou B.Y.Hu H.M.Hu j.F.Hu T.Hu Y.Hu G.S.Huang K.X.Huang L.Q.Huang X.T.Huang Y.P.Huang T.Hussain F.H\"olzken N.H\"usken N.in der Wiesche M.Irshad j.jackson S.janchiv j.H.jeong Q.ji Q.P.ji W.ji X.B.ji X.L.ji Y.Y.ji X.Q.jia Z.K.jia D.jiang H.B.jiang P.C.jiang S.S.jiang T.j.jiang X.S.jiang Y.jiang j.B.jiao j.K.jiao Z.jiao S.jin Y.jin M.Q.jing X.M.jing T.johansson S.Kabana N.Kalantar-Nayestanaki X.L.Kang X.S.Kang M.Kavatsyuk B.C.Ke V.Khachatryan A.Khoukaz R.Kiuchi O.B.Kolcu B.Kopf M.Kuessner X.Kui A.Kupsc W.K\"uhn j.j.Lane P.Larin L.Lavezzi T.T.Lei Z.H.Lei H.Leithoff M.Lellmann T.Lenz C.Li C.Li C.H.Li cheng Li D.M.Li F.Li G.Li H.Li H.B.Li H.j.Li H.N.Li Hui Li j.R.Li j.S.Li K.Li L.j.Li L.K.Li Lei Li M.H.Li P.R.Li Q.M.Li Q.X.Li R.Li S.X.Li T.Li W.D.Li W.G.Li X.Li X.H.Li X.L.Li X.Y.Li Y Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Beihang University Beijing 100191China Bochum Ruhr-University D-44780 BochumGermany Budker Institute of Nuclear Physics SB RAS(BINP) Novosibirsk 630090Russia Carnegie Mellon University PittsburghPennsylvania 15213USA Central China Normal University Wuhan 430079China Central South University Changsha 410083China China Center of Advanced Science and Technology Beijing 100190China China University of Geosciences Wuhan 430074China Chung-Ang University Seoul06974Republic of Korea COMSATS University Islamabad Lahore CampusDefence RoadOff Raiwind Road54000 LahorePakistan Fudan University Shanghai 200433China GSI Helmholtzcentre for Heavy Ion Research GmbH D-64291 DarmstadtGermany Guangxi Normal University Guilin 541004China Guangxi University Nanning 530004China Hangzhou Normal University Hangzhou 310036China Hebei University Baoding 071002China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China Henan University of Science and Technology Luoyang 471003China Henan University of Technology Zhengzhou 450001China Huangshan College Huangshan 245000China Hunan Normal University Changsha 410081China Hunan University Changsha 410082China Indian Institute of Technology Madras Chennai 600036India Indiana University BloomingtonIndiana 47405USA INFN Laboratori Nazionali di Frascati INFN Laboratori Nazionali di FrascatiI-00044FrascatiItaly INFN Laboratori Nazionali di Frascati INFN Sezione di PerugiaI-06100PerugiaItaly INFN Laboratori Nazionali di Frascati University of PerugiaI-06100PerugiaItaly INFN Sezione di Ferrara INFN Sezione di FerraraI-44122FerraraItaly INFN Sezione di Ferrara University of FerraraI-44122FerraraItaly Inner Mongolia University Hohhot 010021China Institute of Modern Physics Lanzhou 730000China Institute of Physics and Technology Peace Avenue 54BUlaanbaatar 13330Mongolia Instituto de A

Using e^(+)e^(−)annihilation data corresponding to an integrated luminosity of 2.93 fb^(−1)taken at the center-of-mass energy√s=3.773 GeV with the BESIII detector,a joint amplitude analysis is performed on the decays D^(0)→π^(+)π^(−)π^(+)π^(−)and D^(0)→π^(+)π^(−)π^(0)π^(0)(non-η).The fit fractions of individual components are obtained,and large interferences among the dominant components of the decays D^(0)→a_(1)(1260)π,D^(0)→π(1300)π,D^(0)→ρ(770)ρ(770),and D^(0)→2(ππ)_(S)are observed in both *** the obtained amplitude model,the CP-even fractions of D^(0)→π^(+)π^(−)π^(+)π^(−)and D^(0)→π^(+)π^(−)π^(0)π^(0)(non-η)are determined to be(75.2±1.1_(stat).±1.5_(syst.))%and(68.9±1.5_(stat).±2.4_(syst.))%,*** branching fractions of D^(0)→π^(+)π^(−)π^(+)π^(−)and D^(0)→π^(+)π^(−)π^(0)π^(0)(non-η)are measured to be(0.688±0.010_(stat.)±0.010_(syst.))%and(0.951±0.025_(stat.)±0.021_(syst.))%,*** amplitude analysis provides an important model for the binning strategy in measuring the strong phase parameters of D^(0)→4πwhen used to determine the CKM angleγ(ϕ_(3))via the B^(−)→DK^(−)decay.

关键词： BESIII D^(0)meson decays amplitude analysis CP-even fraction

Ground-state mass of ^(22)Al and test of state-of-the-art ab initio calculations

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Chinese Physics C 2024年第3期48卷 72-78页

作者：孙铭泽于越王新鹏王猛李健国张玉虎 K.Blaum 陈祖毅陈瑞九邓涵宇付超义葛文文黄文嘉焦红扬李红蕙李宏福罗胤芳廖挺 YuALitvinov 司敏帅鹏史金阳王茜邢元明徐星徐瑚珊许甫荣袁琪 T.Yamaguchi 颜鑫亮杨建成原有进周小红周旭张敏曾奇 CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Max-Planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany GSI Helmholtzzentrum für Schwerionenforschung Planckstraße 164291 DarmstadtGermany Advanced Energy Science and Technology Guangdong Laboratory Huizhou516007China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Department of Physics Saitama UniversitySaitama 338-8570Japan School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

The ground-state mass excess of the T_(z)=−2 drip-line nucleus ^(22)Al is measured for the first time as 18103(10)keV using the newly-developed Bρ-defined isochronous mass spectrometry method at the cooler storage ring in *** new mass excess value allowed us to determine the excitation energies of the two low-lying 1+states in ^(22)Al with significantly reduced uncertainties of 51 *** compared to the analogue states in its mirror nucleus ^(22)F,the mirror energy differences of the two 1^(+)states in the ^(22)Al-^(22)F mirror pair are determined to be−625(51)keV and−330(51)*** excitation energies and mirror energy differences are used to test the state-of-the-art ab initio valence-space in-medium similarity renormalization group calculations with four sets of interactions derived from the chiral effective field *** mechanism leading to the large mirror energy differences is investigated and attributed to the occupation of theπs_(1/2) orbital.

关键词： nuclear mass Bρ-defined IMS mirror energy difference ab initio VS-IMSRG calculations chiral interactions

由超拍电子伏特加速器产生的超高能伽马射线气泡

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Science Bulletin 2024年第4期69卷 449-457页

作者： LHAASO Collaboration Zhen Cao Chuandong Gao Cong Li Ruo-Yu Liu Ruizhi Yang 不详 Key Laboratory of Particle Astrophyics&Experimental Physics Division&Computing Center Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China TIANFU Cosmic Ray Research Center ChengduChina Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China University of Science and Technology of China Hefei 230026China

We report the detection of aγ-ray bubble spanning at least 100deg2 in ultra-high energy(UHE)up to a few PeV in the direction of the star-forming region Cygnus X,implying the presence super PeVatron(s)accelerating protons to at least 10 PeV.A log-parabola form with the photon indexΓ(E)=(2.71±0.02)+(0.11±0.02)×log10(E/10 TeV)is found fitting the gamma-ray energy spectrum of the bubble *** sources,“hot spots”correlated with very massive molecular clouds,and a quasi-spherical amorphousγ-ray emitter with a sharp central brightening are observed in the *** the core of~0.5°,spatially associating with a region containing massive OB association(Cygnus OB2)and a microquasar(Cygnus X-3),as well as previously reported multi-TeV sources,an enhanced concentration of UHEγ-rays is observed with 2 photons at energies above 1 *** general feature of the bubble,the morphology,and the energy spectrum,are reasonably reproduced by the assumption of a particle accelerator in the core,continuously injecting protons into the ambient medium.

关键词： Cosmic rays γ-rays Interstellar medium Star cluster

Revisiting the gravity laws of inter-city mobility in megacity regions

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Science China Earth Sciences 2023年第2期66卷 271-281页

作者： Pengjun ZHAO Haoyu HU Liangen ZENG jun chen Xinyue YE College of Urban and Environmental Sciences Peking UniversityBeijing100871China School of Urban Planning and Design Peking University Shenzhen Graduate SchoolShenzhen518055China Laboratory for Laboratory for Earth Surface System and Human-Earth Relations Ministry of Natural Resources of ChinaPeking University Shenzhen Graduate SchoolShenzhen518055China National Geomatics Center of China Beijing100048China Department of Landscape Architecture and Urban Planning Texas A&M UniversityCollege StationTX77843USA

Inter-city mobility is one of the most important issues in the UN Sustainable Development Goals,as it is essential to access the regional labour market,goods and services,and to constrain the spread of infectious *** the gravity model has been proved to be an effective model to describe mobility among settlements,knowledge is still insufficient in regions where dozens of megacities interact closely and over 100 million people *** addition,the existing knowledge is limited to overall population mobility,while the difference in inter-city travel with different purposes is unexplored on such a large geographic *** revisited the gravity laws of inter-city mobility using the 2.12 billion trip chains recorded by 40.48 million mobile phone users’trajectories in the jing-jin-ji Region,which contains China’s capital ***,unlike previous studies,we found that non-commuting rather than commuting is the dominant type of inter-city mobility(89.3%).Noncommuting travellers have a travel distance 42.3%longer than commuting ***,we developed more accurate gravity models for the spatial distribution of inter-city commuting and non-commuting *** also found that inter-city mobility has a hierarchical structure,as the distribution of inter-city travel volume follows Zipf’s *** particular,the hierarchy of non-commuting travel volume among the cities is more in line with an ideal Zipf distribution than commuting *** findings contribute to new knowledge on basic inter-city mobility laws,and they have significant applications for regional policies on human mobility.

关键词： Mobility Inter-city Travel behaviour Megacity region Zipf’s law China

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湖北省北斗地基增强系统坐标时间序列分析

测绘地理信息 2024年第1期49卷 109-112页

作者：魏以宽邹崇尧陈钧周星宇修延霞邵蕊湖北省测绘工程院湖北武汉430074 吉奥时空信息技术股份有限公司湖北武汉430223 湖北珞珈实验室湖北武汉430079

解算了湖北省北斗地基增强系统的北斗坐标时间序列,并对坐标时间序列性能进行了分析,最后给出北斗和GPS坐标时间序列对比分析方法及案例,从而为省级连续运行基准站快速更新维护提供一种参考方案。

关键词： GNSS 北斗 GPS 时间序列分析大地基准维护

Attention-based LSTM predictive model for the attitude and position of shield machine in tunneling

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Underground Space 2023年第6期13卷 335-350页

作者： Qing Kang Elton j.chen Zhong-Chao Li Han-Bin Luo Yong Liu State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China School of Civil&Hydraulic Engineering Huazhong University of Science&TechnologyWuhan 430074China Tunnel Engineering Company Wuhan Municipal Construction Group Co.LtdWuhan 430023China

Shield machine may deviate from its design axis during excavation due to the uncertainty of geological environment and the complexity of *** study therefore introduced a framework to predict the attitude and position of shield machine by combining long short-term memory(LSTM)model with attention *** data obtained from the Wuhan Rail Transit Line 6 project were utilized to verify the feasibility of the proposed *** adding the attention mechanism into the LSTM model,the proposed model can focus more on parameters with higher *** analysis based on Pearson correlation coefficient was conducted to improve the prediction efficiency and reduce the irrelevant input *** with LSTM model,LSTM-attention model has higher *** mean value of coefficient of determination(R^(2))increases from 0.625 to 0.736,and the mean value of root mean square error(RMSE)decreases from 3.31 to *** proposed LSTM-attention model can provide an effective prediction for attitude and position of shield machine in practical tunneling engineering.

关键词： LSTM Shield machine Attitude and position prediction Attention mechanism Tunnel excavation

云微物理参数化的改进及其对川藏铁路沿线降水的模拟优势

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中国科学：地球科学 2024年第3期54卷 874-891页

作者：徐晓齐衡志炜李跃清王顺久李建王元陈景华张佩文陆春松南京气象科技创新研究院中国气象局交通气象重点开放实验室南京210041 中国气象局成都高原气象研究所高原与盆地暴雨旱涝灾害四川省重点实验室成都610072 中国气象科学研究院灾害天气国家重点实验室北京100081 兰州大学西部生态安全省部共建协同创新中心兰州730000 南京信息工程大学中国气象局气溶胶与云降水重点开放实验室/气象灾害预报预警与评估协同创新中心南京210044

川藏铁路是我国铁路网的重要组成部分,该区域山洪、滑坡等地质灾害多发,而降水是诱发这些灾害的重要原因,因此该区域降水的准确模拟是至关重要的.本文改进了西南区域业务预报模式云微物理方案中不确定性较大的物理过程,包括云滴活化、... 详细信息

川藏铁路是我国铁路网的重要组成部分,该区域山洪、滑坡等地质灾害多发,而降水是诱发这些灾害的重要原因,因此该区域降水的准确模拟是至关重要的.本文改进了西南区域业务预报模式云微物理方案中不确定性较大的物理过程,包括云滴活化、云水自动转化、云雨碰并和混合蒸发过程.原方案中,不同大小的云水含量对应着相同的云滴浓度,与实际不符,造成云滴尺度过大,相关物理过程速率(比如云水自动转化率)过快,导致降水高估.新方案克服了云滴尺度过大的问题,云水自动转化和云雨碰并过程均与随机收集方程更为接近,云滴蒸发机制更符合云中实际物理过程.基于新旧方案,模拟了川藏铁路沿线2021年汛期的多次降水过程,利用地面观测和卫星反演资料,评估了模拟结果.新方案对云物理量的模拟变得更为合理,使原方案对液水路径和液滴半径的模拟偏差从2倍减少到1倍以内,并显著缓解了原方案对降水强度和范围的高估情况,降水的平均均方根误差减小22%.本文所得结果能够为提高模式在该区域预报降水和灾害防控能力提供科学参考.

关键词：川藏铁路云微物理降水模式改进