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江西全南县青龙山萤石矿稀土元素地球化学特征及成因分析

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矿产与地质 2024年第1期38卷 106-113页

作者：杨洲畬叶发江西省地质局第七地质大队江西赣州341000

本文旨在对江西省全南县青龙山萤石矿床的地球化学特征及成因进行探讨,通过对青龙山萤石矿区矿石和围岩样品进行稀土元素分析,青龙山萤石矿矿石的∑Ree平均含量为88.186×10^(-6),δeu为0.23~0.61,δCe为0.78~0.91;围岩的∑Ree平均含量... 详细信息

本文旨在对江西省全南县青龙山萤石矿床的地球化学特征及成因进行探讨,通过对青龙山萤石矿区矿石和围岩样品进行稀土元素分析,青龙山萤石矿矿石的∑Ree平均含量为88.186×10^(-6),δeu为0.23~0.61,δCe为0.78~0.91;围岩的∑Ree平均含量为184.52×10^(-6),δeu为0.31~0.69,δCe为0.85~1,萤石矿石和围岩的稀土元素配分模式具有相似性和同步性,呈轻稀土相对富集的右倾型,eu中等亏损,Ce弱亏损。矿石与围岩的稀土地球化学研究显示,该萤石矿床至少存在两个成矿期次,为岩浆热液成矿,成矿环境为稳定的较还原条件,成矿流体温度在200℃左右。

关键词：青龙山萤石矿稀土元素地球化学特征江西全南

Supramolecular Polymerization of Hydrogen-Bonded Trimers in Bulk and Aqueous Medium

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CCS Chemistry 2024年第6期6卷 1458-1465页

作者： Freek V.de graaf Stef A.H.Jansen Sandra M.C.Schoenmakers Bas van Genabeek Marle e.J.Vleugels Bart W.L.van den Bersselaar e.W.Meijer Ghislaine Vantomme Institute for Complex Molecular Systems Laboratory of Macromolecular and Organic ChemistryEindhoven University of Technology5600 MBEindhoven School of Chemistry and Rna Institute University of New South WalesSydneyNew South Wales 2052

Synthetic molecules that form functional noncovalent assemblies in water have received much attention for their potential applications as *** this work,we introduce a novel water-compatible monomer based on the phthalhydrazide moiety that assembles into hydrogen-bonded trimeric *** bulk,the material exhibits a cylindrical nanostructure in the liquid-crystalline phase at elevated temperatures,morphologically distinct from the crystalline lamellar *** water,these molecules effectively form cylinders in a one-dimensional fashion,yielding fibrous *** formation of these supramolecular polymers follows a cooperative mechanism,as evidenced by denaturation *** trimerized pattern represents a new category of aqueous su pramolecular polymers with future prospects for functional complex molecular systems.

关键词： noncovalent chemistry supramolecular polymers hydrogen bonding cooperativity nanostructure

COMPLeXeS OF RARe eARTH NITRATe WITH SCHIFF BASe DeRIVeD FROM VANILLIN AND P-TOLUidINe

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Chinese Chemical Letters 1990年第2期1卷 119-120页

作者： Guo fa LIU Bin LI Chong wu na Kun Yuan MAO Institute of Material Science,Jilin University,Changchun,130023

In this paper,complexes of rare earth nitrate with Schiff base derived from vanillin(3-methoxy-4-hydroxy-benzaldehyde)and p-toluidine[LnL_2(NO_3)_2]NO_3(Ln=La-eu except Pm,L=Schiff base ligand) have been prepared and ... 详细信息

关键词： COMPLeXeS OF RARe eARTH NITRATe WITH SCHIFF BASe DeRIVeD FROM VANILLIN AND P-TOLUidINe

Syntheses,Structures,and Luminescent Properties of New Zn~Ⅱ-Y~Ⅲ and Zn~Ⅱ-Ln~Ⅲ Schiff Base Complexes

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Chinese Journal of Structural Chemistry 2015年第8期34卷 1273-1280页

作者： HU Jin-fa QIN Ya-Ru LI Yu LIU Wei WANG Yong LI Ya-Hong College of Chemistry Chemical Engineering and Materials ScienceSoochow University

eight new ZnⅡ-yⅢ and ZnⅡ-LnⅢ heterometallic Schiff base complexes： MZnL2（NO3）3 （M = Y （1）, La （2）, Pr （3）, Nd （4）, eu （5）, Gd （6）, Dy （7）, er （8）; L = 2-（（（2- （imidazo[1,5-a]pyridin-3-yl）phenyl）imino）methyl）-6-methoxyphenol）, have been rationally synthesized under solvothermal conditions and characterized by IR, elemental analyses （eA）, single-crystal X-ray diffraction, and powder XRD. Furthermore, luminescence in the visible region for solids 1-8 suggested zine/ligand-centered emission at room temperature.

关键词： heterometallic complex, crystal structure, luminescence

Radioisotope production using lasers:From basic science to applications

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Matter and Radiation at extremes 2024年第3期9卷 31-44页

作者： M.R.D.Rodrigues A.Bonasera M.Scisciò J.A.Pérez-Hernández M.ehret F.Filippi P.L.Andreoli M.Huault H.Larreur D.Singappuli D.Molloy D.Raffestin M.Alonzo G.G.Rapisarda D.Lattuada G.L.Guardo C.Verona Fe.Consoli G.Petringa A.Mcnamee M.La Cognata S.Palmerini T.Carriere M.Cipriani G.Di Giorgio G.Cristofari R.De Angelis G.A.P.Cirrone D.Margarone L.Giuffrida D.Batani P.Nicolai K.Batani R.Lera L.Volpe D.Giulietti S.Agarwal M.Krupka S.Singh fa.Consoli Cyclotron Institute Texas A&M UniversityCollege StationTexas 77840USA Laboratori nazionali del Sud Istituto Nazionale di Fisica Nucleare(LNS-INFN)CataniaItaly eNeA Fusion and Technologies for Nuclear Safety and Security Department-CFrascatiItaly Centro de Láseres Pulsados(clpu) VillamayorSpain Universidad de Salamanca SalamancaSpain Centre Lasers Intenses et Applications(CeLIA) Universitéde BordeauxCNRSCEATalenceFrance HB11 energy Holdings Pty FreshwaterNew South WalesAustralia School of Mathematics and Physics Queen’s University BelfastBelfastUnited Kingdom Dipartimento di Fisica e Astronomia“e.Majorana ”Università di CataniaCataniaItaly facoltàdi Ingegneria e Architettura Universitàdegli Studi di Enna“Kore”EnnaItaly Dipartimento di Ingegneria Industriale Universitàdi Roma“Tor Vergata”RomaItaly Dipartimento di Fisica e Geologia Universitàdegli Studi di PerugiaPerugiaItaly Istituto nazionale di Fisica Nucleare Sezione di PerugiaPerugiaItaly eLI Beamlines facility the Extreme Light Infrastructure ERICDolni BrezanyCzech Republic eTSIA Universidad Politécnica de MadridMadridSpain Dipartimento Fisica “E.Fermi”Universitàdi Pisa and INFNPisaItaly FZU–Institute of Physics of Czech Academy of Sciences PragueCzech Republic Institute of Plasma Physics of Czech Academy of Sciences PragueCzech Republic

The discovery of chirped pulse amplification has led to great improvements in laser technology,enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused to a few *** with energies of tens of MeV can be accelerated using,for instance,target normal sheath acceleration and focused on secondary *** such conditions,nuclear reactions can occur,with the production of radioisotopes suitable for medical *** use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on *** this paper,we study the production of^(67)Cu,^(63)Zn,^(18)F,and^(11)C,which are currently used in positron emission tomography and other *** the same time,we study the reactions^(10)B(p,α)^(7)Be and^(70)Zn(p,4n)^(67)Ga to put further constraints on the proton distributions at different angles,as well as the reaction^(11)B(p,α)^(8)Be relevant for energy *** experiment was performed at the 1 PW laser facility at VegaⅢin Salamanca,*** distributions of radioisotopes in the forward(with respect to the laser direction)and backward directions were measured using a high purity germanium *** results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera[*** ***.,Sect.A 637,164–170(2011)].

关键词： purity estimates backward

Two-carrier transport in SrMnBi2 thin films

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Frontiers of physics 2017年第3期12卷 61-72页

作者： Xiao Yan Cheng Zhang Shan-Shan Liu Yan-Wen Liu David Wei Zhang fa-Xian Xiu Peng Zhou State Key Laboratory of ASIC and System School of Microelectronics Fudan University Shanghai 200433 China State Key Laboratory of Surface Physics and Department of Physics Fudan University Shanghai 200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093 China

Monocrystalline SrMnBi2 thin films were grown by molecular beam epitaxy （MBe）, and their transport properties were investigated. A high and unsaturated linear magnetoresistance （MR） was observed, which exhibited a transition from a semi-classical weak-field B2 dependence to a high-field linear dependence. An unusual nonlinear Hall resistance was also observed because of the anisotropic Dirac fermions. The two-carrier model was adopted to analyze the unusual Hall resistance quantitatively. The fitting results yielded carrier densities and mobilities of 3.75×10^14 cm^-2 and 850 cm^2·V^-1·s^-1, respectively, for holes, and 1.468×10^13 cm^-2, 4118 cm^2·V^-1·s^-1, respectively, for electrons, with a hole-dominant conduction at 2.5 K. Hence, an effective mobility can be achieved, which is in reasonable agreement with the effective hole mobility of 1800 cm^2·V^-1·s^-1, extracted from the MR. Further, the angle-dependent MR, proportional to cos 0, where 0 is the angle between the external magnetic field and the perpendicular orientation of the sample plane, also implies a high anisotropy of the Fermi surface. Our results about SrMnBi2 thin films, as one of a new class of AeMnBi2 and AeMnSb2 （Ae = Ca, Sr, Ba, Yb, eu） materials, suggest that they have a lot of exotic transport properties to be investigated, and that their high mobility might facilitate electronic device applications.

关键词： SrMnBi2 thin films magnetoresistance two carriers anisotropic Dirac fermions

Rare earth elemental and Sr isotopic evidence for seawater intrusion event of the Songliao Basin 91 million years ago

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Petroleum Science 2023年第3期20卷 1347-1362页

作者： Yu-Ke Liu Hua-jian Wang Jin-You Zhang Zhen-Wu Liu fa-Zi Chen Xiao-Mei Wang Shui-Chang Zhang He Liu Research Institute of Petroleum exploration and Development Beijing100083China Key Laboratory of Petroleum Geochemistry China National Petroleum CorporationBeijing100083China Daqing Oil Field Company China National Petroleum CorporationDaqingHeilongjiang163000China School of Ocean Sciences China University of GeosciencesBejing100083China

Petrogenesis of lacustrine dolostone is closely related with paleo-lake water *** we report the high spatial-resolution petrographic and geochemical results of a lacustrine dolomite nodule from the Qingshankou Formation,the Songliao *** and elemental signatures confirm the protogenetic origin of this nodule and its effectiveness in recording geochemical characteristics of paleo-lake water during *** low Y/Ho ratios,middle rare earth element(MRee)enrichment and subtle positive eu anomalies within the nodule indicate a fresh water ***,the Sr isotope values in the core of the nodule(0.7076-0.7080)are close to contemporaneous seawater(0.7074),yet different from the modern river(0.7120)and the host black shale(0.7100).On the premise of excluding the influence of hydrothermal fluids,the significantly low strontium isotope values of the lacustrine dolomite might be caused by seawater interference during *** findings demonstrate that lacustrine dolomite within black shales is not only a faithful tracer of diagenetic water environment,but also a novel and easily identified mineralogical evidence for episodic seawater intrusion event(91 Ma)in the Songliao Basin,which supplements other paleontological and geochemical evidence.

关键词： Songliao Basin Lacustrine dolostone Seawater intrusion Rare earth elements Strontium isotope

中欧班列冷链运输熔断机制的适用性和风险防控

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综合运输 2024年第3期46卷 138-144页

作者：李林卿吕敏法慧妍宫丹青陈变宁刘伟达北京交通大学交通运输学院北京100044 西南交通大学交通运输与物流学院四川成都611756 国家铁路局市场监测评价中心北京100036 中国铁路北京局集团有限公司货运部北京100860 中国铁路北京局集团有限公司北京货运中心北京100076

新冠肺炎疫情以来,全球物流格局发生了重大变化,航空和海运受疫情影响造成国际运输渠道大幅缩减,中欧班列凭借自身优势逆流而上,为战胜疫情做出了重要贡献。但中欧班列冷链运输也成为了“新冠”病毒传播的重要途径,因此对其熔断机制和... 详细信息

新冠肺炎疫情以来,全球物流格局发生了重大变化,航空和海运受疫情影响造成国际运输渠道大幅缩减,中欧班列凭借自身优势逆流而上,为战胜疫情做出了重要贡献。但中欧班列冷链运输也成为了“新冠”病毒传播的重要途径,因此对其熔断机制和风险防控进行研究显得尤为重要。通过对中欧班列和航空熔断机制进行介绍,结合发展现状,提出中欧班列冷链运输在监管、标准法规、信息化、产业链等方面存在的问题,并对熔断机制的适用性进行探讨。从地方人民政府、市场监管、生产、铁路、交通运输等角度出发,提出各部门风险联防联控手段,并提出冷链运输发展宏观对策。

关键词：新冠疫情中欧班列冷链运输熔断机制风险防控

论运用WTO规则解决美欧对华纺织品贸易摩擦

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中南民族大学学报（人文社会科学版） 2006年第6期26卷 110-115页

作者：宋才发中央民族大学法学院北京100081

美欧联手对华纺织品设立贸易限制的依据是《中国加入工作组报告书》的第242条款,而以此设限缺乏法律根据。必须依法应对美国的“特保”限制,美欧设限损害了中国纺织业的发展和W TO的信誉度。为解决与美欧的贸易摩擦,中国主动提高纺织品... 详细信息

美欧联手对华纺织品设立贸易限制的依据是《中国加入工作组报告书》的第242条款,而以此设限缺乏法律根据。必须依法应对美国的“特保”限制,美欧设限损害了中国纺织业的发展和W TO的信誉度。为解决与美欧的贸易摩擦,中国主动提高纺织品出口关税税率,政府实施“主动配额”的斡旋方式,对纺织品实施临时出口许可管理。中国纺织品服装企业必须正确应对国际竞争中的贸易壁垒。

关键词：纺织品服装贸易限制 WTO规则依法解决