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长江三角洲北翼更新世以来的水土环境地球化学特征及其环境指示意义

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海洋学报 2024年第3期46卷 33-53页

作者：苟富刚龚绪龙刘源江苏省地质调查研究院江苏南京210049 自然资源部地裂缝地质灾害重点实验室江苏南京210049

江苏沿海平原是江苏省域水资源脆弱带,地下水咸化已成为较为严重的生态环境问题。为了解析长江三角洲北翼地区更新世以来地下水的补给及其盐分来源,布设一口275 m的深井HYRD1,全孔连续采集易溶盐样品、土工样品、水样。在区域采集地表... 详细信息

江苏沿海平原是江苏省域水资源脆弱带,地下水咸化已成为较为严重的生态环境问题。为了解析长江三角洲北翼地区更新世以来地下水的补给及其盐分来源,布设一口275 m的深井HYRD1,全孔连续采集易溶盐样品、土工样品、水样。在区域采集地表水、浅层与深层地下水、海水样品。采用易溶盐指标结合土工指标(含水率、湿密度、比重)获取了HYRD1高精度孔隙水的水化学特征。采用Piper三线图、gibbs图、离子比值法等结合δD、δ^(18)O数据、^(14)C测年数据解析了更新世以来地下水的补给及其盐分来源。结果表明:土体盐分主要为NaCl,盐渍土占比为25%。盐渍土主要分布在q_(p3)弱透水层、 q_(p2)地层与q_(p1)上段地层。孔隙水水化学类型为Cl-Na型(仅q_(p1)下段个别点为HCO~-_3-Ca·Na),微咸水占比7%,咸水占比49%,盐水占比44%。微咸水主要分布在q_(p1)下段砂层中。潜水的δ^(18)O、δD说明潜水来源为大气降水,且受到了较为强烈的蒸发作用。弱透水层孔隙水、承压水的δ^(18)O、δD投点位于标准海水稀释线附近,且随着深度的增加,δ^(18)O、δD有减小趋势,说明海水混合作用随着深度的增加而减小。q_(p1)弱透水层多见钙质结核,说明了q_(p1)地层成土后受到了强烈的蒸发作用。HYRD1 q_(p1)上段及上覆地层盐分主要来源于5期海侵、蒸发盐岩与硅酸盐风化溶解,q_(p1)下段地层盐分主要来源为地壳源。地下水化学成分受到了水岩作用、蒸发浓缩作用与人类活动等的影响。

关键词：沉积环境含盐特征易溶盐孔隙水弱透水层沿海含水层

不同层结条件下海浪生湍流混合特征分析及其对上层海洋的影响

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海洋科学进展 2024年第3期42卷 437-451页

作者：庄展鹏袁业立自然资源部第一海洋研究所山东青岛266061 自然资源部海洋环境科学与数值模拟重点实验室山东青岛266061 崂山实验室区域海洋动力学与数值模拟功能实验室山东青岛266061

上层海洋混合过程的动力学研究和数值模拟一直是海洋和气象学家关注的重点之一,其中上层海洋垂向混合参数化方案的不准确直接影响海洋模式的模拟效果。风生海浪对海气相互作用以及上层海洋的内部混合都起到极为重要的作用。本文基于包... 详细信息

上层海洋混合过程的动力学研究和数值模拟一直是海洋和气象学家关注的重点之一,其中上层海洋垂向混合参数化方案的不准确直接影响海洋模式的模拟效果。风生海浪对海气相互作用以及上层海洋的内部混合都起到极为重要的作用。本文基于包含垂向层结效应的海浪生湍流混合系数理论模型,开展不同层结条件下海浪生湍流混合系数的分布变化特征分析。构建了一维理想解析实验和准全球算例,结果表明,在100 m以浅的上层海洋中,混合层深度与上述混合系数呈现较为显著的负相关关系,当跃层或混合层深度较大时能够显著增强垂向混合过程,进而使表层暖水下降至更深的位置,加深混合层深度模拟结果。主要原因是由于深跃层条件下表层的层结效应较弱,因而对混合的抑制作用较小。此外,在准全球算例中海浪生湍流混合方案可显著提高海洋环流模式对上层海洋温度结构的模拟能力,模式对跃层处WOA13实测数据的模拟精度最高可提升60%以上。

关键词：海浪生湍流混合垂向层结条件海洋环流数值模拟跃层深度

Fermi Surface Nesting with Heavy quasiparticles in the Locally Noncentrosymmetric Superconductor CeRh2As2

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Chinese Physics Letters 2024年第9期41卷 107-121页

作者： Yi Wu Yongjun Zhang Sailong Ju Yong Hu Yanen Huang Yanan Zhang Huali Zhang Hao Zheng guowei Yang Evrard-Ouicem Eljaouhari Baopeng Song Nicholas C.Plumb Frank Steglich Ming Shi gertrud Zwicknagl Chao Cao Huiqiu yuan Yang Liu Center for Correlated Matter and School of Physics Zhejiang UniversityHangzhou 310058China Institute for Advanced Materials Hubei Normal UniversityHuangshi 435002China Swiss Light Source Paul Scherrer InstitutCH-5232 Villigen PSISwitzerland Institut for Mathematische Physik 38106 BraunschweigGermany Max Planck Institute for Chemical Physics of Solids 01187 DresdenGermany Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China State Key Laboratory of Silicon Materials Zhejiang UniversityHangzhou 310058China

The locally noncentrosymmetric heavy fermion superconductor CeRh2As2 has attracted considerable interests due to its rich superconducting phases,accompanied by possible quadrupole density wave and pronounced antiferromagnetic *** understand the underlying physics,here we report measurements from highresolution angle-resolved *** results reveal fine splittings of the conduction bands related to the locally noncentrosymmetric structure,as well as a quasi-two-dimensional Fermi surface(FS)with strong 4𝑓*** FS shows signs of nesting with an in-plane vector q1=(π/α,π/α),which is facilitated by the heavy bands nearˉ𝑋arising from the characteristic conduction-X *** FS nesting provides a natural explanation for the observed antiferromagnetic spin fluctuations at(π/α,π/α),which might be the driving force for its unconventional *** experimental results can be reasonably explained by density functional theory plus dynamical mean field theory calculations,which can capture the strong correlation *** study not only provides spectroscopic signature of the key factors underlying the field-induced superconducting transition,but also uncovers the critical role of FS nesting and lattice Kondo effect in the underlying magnetic fluctuations.

关键词： symmetric Fermi conduction

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

All-optical μ^- acceleration in the laser wakefield

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High Power Laser Science and Engineering 2018年第4期6卷 119-124页

作者： F.Zhang Z.g.Deng L.q.Shan Z.M.Zhang B.Bi D.X.Liu W.W.Wang Z.q.yuan C.Tian S.q.Yang B.Zhang Y.q.gu Science and Technology on Plasma Physics Laboratory Laser Fusion Research CenterChina Academy of Engineering Physics IFSA Collaborative Innovation Center Shanghai Jiao Tong University

Muons produced by the Bethe–Heitler process from laser wakefield accelerated electrons interacting with high Z materials have velocities close to the laser wakefield. It is possible to accelerate those muons with laser wakefield *** for the first time we propose an all-optical ‘generator and Booster’ scheme to accelerate the produced muons by another laser wakefield to supply a prompt, compact, low cost and controllable muon source in laser laboratories. The trapping and acceleration of muons are analyzed by one-dimensional analytic model and verified by two-dimensional particle-in-cell(PIC) simulation. It is shown that muons can be trapped in a broad energy range and accelerated to higher energy than that of electrons for longer dephasing length. We further extrapolate the dependence of the maximum acceleration energy of muons with the laser wakefield relativistic factor γ and the relevant initial energy E_0. It is shown that a maximum energy up to 15.2 geV is promising with γ = 46 and E_0= 1.45 ge V on the existing short pulse laser facilities.

关键词： laser wakefield acceleration muon source

氧气反应模式-四极杆ICP-MS定量高温合金中痕量元素及质谱干扰消除机理研究

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质谱学报 2024年第4期45卷 531-539,I0004页

作者：冯媛媛周涛唐一川张见营李彭辉天津理工大学天津300384 中国计量科学研究院北京100029

本研究建立了氧气反应模式-四极杆电感耦合等离子体质谱(q-ICP-MS)法准确定量高温合金中痕量杂质元素,对不同碰撞/反应模式消除质谱干扰的效果进行研究。结果表明,氧气动态反应池(DRC-O_(2))模式下,目标元素Cd的多原子离子质谱干扰能够... 详细信息

本研究建立了氧气反应模式-四极杆电感耦合等离子体质谱(q-ICP-MS)法准确定量高温合金中痕量杂质元素,对不同碰撞/反应模式消除质谱干扰的效果进行研究。结果表明,氧气动态反应池(DRC-O_(2))模式下,目标元素Cd的多原子离子质谱干扰能够被有效去除;在优化气流为2 mL/min时,信噪比达到最高,检出限较标准模式(STD)降低了近3个数量级。此外,还研究了质谱干扰的消除机理,发现对于元素X(X=Rb、Nb、Mo、Cs、Ta、W或U),当X-O键能大于O-O键能时,质谱干扰组分XO转化成非干扰组分XOO为自发反应,因此,O_(2)充足时更容易生成XOO,从而消除XO干扰。在此基础上,采用高浓度基体模拟溶液(Mo、Nb、Ta、W)分别对痕量Cd、Ag、Au、Hg元素测量的方法学参数进行评估,方法检出限0.08~0.31μg/g、测量重复性相对标准偏差(RSD)2.3%~3.1%(n=6),加标回收率98%~103%,并进一步使用高温合金标准物质验证了方法的可靠性。最后,对3类典型牌号高温合金样品中的痕量杂质进行测量,证明该方法的分析速度快、检出限低、准确可靠,能够满足高温合金中主量Mo、Nb、Ta、W元素存在时被干扰杂质的测量要求。

关键词：四极杆电感耦合等离子体质谱(q-ICP-MS) 高温合金质谱干扰痕量元素机理研究

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State estimation over a communication network:measurement or estimate communication?

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控制理论与应用（英文版） 2010年第1期8卷 20-26页

作者： Ling SHI Ye yuan Michael Z. q. CHEN Electronic and Computer Engineering Hong Kong University of Science and Technology Hong Kong China Control group Department of Engineering University of Cambridge Cambridge CB2 IPZ UK Department of Automation Nanjing University of Science and Technology Nanjing Jiangsu 210094 China)

In this paper we consider the problem of state estimation over a communication network. Using estimation quality as a metric, two communication schemes are studied and compared. In scheme one, each sensor node communicates its measurement data to the remote estimator, while in scheme two, each sensor node communicates its local state estimate to the remote estimator. We show that with perfect communication link, if the sensor has unlimited computation capability, the two schemes produce the same estimate at the estimator, and if the sensor has limited computation capability, scheme one is always better than scheme two. On the other hand, when data packet drops occur over the communication link, we show that if the sensor has unlimited computation capability, scheme two always outperforms scheme one, and if the sensor has limited computation capability, we show that in general there exists a critical packet arrival rate, above which scheme one outperforms scheme two. Simulations are provided to demonstrate the two schemes under various circumstances.

关键词： Networked estimation Kalman filtering Packet-dropping network

Finite Element Analysis of Push-Out Test of SiC Fiber Reinforced Titanium Matrix Composites

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稀有金属材料与工程 2009年第A3期38卷 50-53页

作者： yuan M N Yang Y q Huang B Zhang R J School of Materials Northwestern Polytechnical University Xi＇an 710072 China

Based on the interphase layer model and the spring layer model, an improved interface model was developed to evaluate the interfacial shear strength of Titanium matrix composites(TMCs) and to analyze the effects of various parameters on the interfacial properties. The results showed that the improved interface model is more suitable for calculating the interfacial properties of SiC fiber reinforced titanium matrix composites. The interfacial shear strength of SiC/Timetal-834 predicted is 500 MPa. In addition, in order to better understand the interfacial properties of composites, some push out phenomenon were analyzed.

关键词：复合材料剪切强度碳化硅纤维物理性能

MODELINg OF STATIC RECRYSTALLIZATION KINETICS OF Nb-BEARINg STEELS

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Acta Metallurgica Sinica(English Letters) 2006年第4期19卷 271-278页

作者： L.q. Ma Z.Y. Liu S.H. Jiao X.q. yuan D. Wu The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110004 China Institute of Research and Development Baosteel Co. Ltd Shanghai 201900 China

By using isothermal double hit compression tests and applying the 2% offset method, a new model was developed to predict the microstructural evolution of Nb-bearing steels at temperatures above and below the start temperature of strain-induced precipitation （Tp）. The Tp was developed as a function of true strain, initial austenite grain size and the Nb content. The activation energy of static recrystallization （qrex） was expressed as a function of the content of different alloy elements. It was found that Nb played the most important role in increasing the value of qrex, The microstructural observations and measurements confirmed the validity of the model developed in the present investigation.

关键词： Nb-bearing steel static recrystallization Tp (start temperature of strain-induced precipitation) activation energy