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秘鲁铜元素地球化学空间分布及对成矿远景区的预测

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地学前缘 2025年第1期32卷 205-218页

作者：胡庆海王学求张必敏迟清华王强孙彬彬周建王玮 Igor ESPINOzA VERDE Alex AGURTO CORNEJO joel OTERO AGUILAR 盘炜刘汉粮田密吴慧自然资源部地球化学探测重点实验室中国地质科学院地球物理地球化学勘查研究所河北廊坊065000 联合国教科文组织全球尺度地球化学国际研究中心河北廊坊065000 中国地质调查局发展研究中心北京100037 秘鲁能源矿业部地质矿产冶金研究院利马51

秘鲁位于南美洲西岸,作为安第斯成矿带的重要组成部分,矿产资源丰富,铜矿资源储量和产量位居世界第二。本文首次对秘鲁开展全国范围全球尺度地球化学调查工作,获得汇水域沉积物样品共416件,秘鲁全境铜元素含量为2.38~495μg/g,背景值(... 详细信息

秘鲁位于南美洲西岸,作为安第斯成矿带的重要组成部分,矿产资源丰富,铜矿资源储量和产量位居世界第二。本文首次对秘鲁开展全国范围全球尺度地球化学调查工作,获得汇水域沉积物样品共416件,秘鲁全境铜元素含量为2.38~495μg/g,背景值(中位数)为24.0μg/g。秘鲁全境、沿海带、安第斯山区和亚马孙平原的表层(深层)汇水域沉积物中铜元素平均含量依次为31.4(31.6)、45.6(32.2)、47.5(48.2)和21.3μg/g(24.9μg/g)。地球化学图显示,秘鲁铜空间分布整体呈现出西高东低的趋势,西部沿海带和中部安第斯山区含量较高,东部亚马孙平原区含量较低的特征。本文选用75%累积频率作为异常下限值,圈定出5处铜地球化学异常,其中两处达到地球化学巨省规模,两处达到地球化学域规模。同时,讨论铜地球化学异常的来源和影响因素,解析与之对应的矿产资源响应,秘鲁良好的构造演化环境,为大型、超大型铜矿床的形成提供有利条件。太平洋纳斯卡板块向南美大陆不断俯冲变换,致使洋壳发生部分熔融,产生强烈而广泛的中酸性岩浆活动,且岩浆中铜含量大规模富集,局部地区在特定环境下富集成矿。这一构造运动导致铜元素在秘鲁空间分布上呈现出多个地球化学块体,可能也是铜地球化学异常形成的原因之一。这些巨大的地球化学块体发现可用于未来寻找铜矿集区或大型、超大型铜矿床,圈定找矿远景区,并可以降低找矿风险,提高找矿效率,缩短找矿周期。研究圈定的地球化学找矿远景区,可为秘鲁铜矿勘查开发利用提供基础资料和数据。

关键词：秘鲁铜汇水域沉积物地球化学填图成矿远景区

Dimensional heterojunction design:The rising star of 2D bismuthbased nanostructured photocatalysts for solar-to-chemical conversion

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Nano Research 2023年第4期16卷 4310-4364页

作者： joel Jie Foo Sue-Faye Ng Wee-Jun Ong School of Energy and Chemical Engineering Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Center of Excellence for NaNo Energy&Catalysis Technology(CONNECT) Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia College of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China Shenzhen Research Institute of Xiamen University Shenzhen 518057China

With the fast-pace digitalization evolution in the current generation’s lifestyle and the industry revolution,the energy demand has been ***,the two-dimensional(2D)bismuth-based nanomaterials emerged as a promising photocatalyst candidate in solar fuel conversion,not only for its exceptional light absorption capability and tunable optical properties,but it also can be synthesized into diverse variety of nanomaterials with different ranges of potential gap and band position to fulfill the potential requirement of wide range of photocatalytic ***,the weak light harvesting ability and ultrafast charge recombination has restricted its potential in commercial ***,recent researches have been focusing on tackling these issues by incorporating some modification strategies such as heteroatom doping,vacancy engineering,facet engineering,bismuth rich strategy and heterojunction ***,this review article presents the state-of-the-art modifications on 2D bismuth-based parent material,specifically on the relationship between each of the modification strategy on the electronic properties and surface chemistry in achieving boosted photocatalytic *** the view of the unique charge interaction between two semiconductors with different dimensions,we systematically discuss the rational heterostructure design from the dimensionality perspective,namely,point-to-face,line-to-face,face-to-face,and bulk-to-face in solar fuel conversion to provide inspiring insights for future interface ***,the challenges and the future research outlook in the solar-to-fuel conversion are highlighted to push forward the design of high-performance bismuth-based photocatalyst in realizing commercialscale solar-to-fuel conversion.

关键词： 2D heterojunction 2D nanomaterial CO_(2)reduction water splitting N2 fixation z-scheme

PSA Screening for Prostate Cancer in Men under the Age of 65: A Review of Current Practice

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Open Journal of Urology 2018年第5期8卷 135-160页

作者： Andrew H. Khalifa joel z. Cornfield St. James School of Medicine Anguilla The Grenadines Attending Staff Adventist Hinsdale Hospital and Jesse Brown Veteran’s Administration Hospital Chicago USA

Purpose: To review current practice in the use of Prostate Specific Antigen (PSA) testing and assess the overall risks and benefits of PSA testing for Adenocarcinoma of the Prostate, specifically in men under age 65, and those living with risk factors for the disease. Materials and Methods: An extensive literature review of PSA testing in various age groups was conducted with the goal being to review PSA screening trends and assess current recommendations regarding PSA Screening for Adenocarcinoma of the Prostate in various age groups, focusing on studies directed towards patients under the age of 65 and the long-term risks and benefits of PSA screening in the diagnostic algorithm. In order to reduce bias, we assessed our sources for variables such as reporting, measurement and/or selection bias. Our conclusions were then compared with current recommendations. Relevant studies with data compiled after 2004, centered around PSA screening in men under the age of 65 in general and specifically in men with risk factors for developing Adenocarcinoma of the Prostate were included. Editorials, newspaper articles and other non-scholarly and non-peer reviewed sources were automatically excluded.

关键词： Adenocarcinoma Adenocarcinoma of the Prostate Aggressive Disease

Facilitation by nurse plants contributes to vegetation recovery in human-disturbed desert ecosystems

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Journal of Plant Ecology 2016年第5期9卷 485-497页

作者： Ernesto I.Badano Omar R.Samour-Nieva joel Flores JoséL.Flores-Flores Jorge A.Flores-Cano Juan P.Rodas-Ortíz División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José2055Colonia Lomas 4ta SecciónC.P.78216San Luis PotosíMéxico Instituto de Investigación de zonas Desérticas Universidad Autónoma de San Luis PotosíAltair 200Fraccionamiento del LlanoC.P.78377San Luis PotosíMéxico Facultad de Agronomía Universidad Autónoma de San Luis PotosíKm.14.5 Carretera San Luis-MatehualaApdo.Postal 32Soledad de Graciano SánchezC.P.78321San Luis PotosíMéxico

Aims Facilitation by nurse plants is a common interaction in harsh environments and this positive plant-plant interaction may promote vegetation recovery in ecosystems affected by human *** the relevance of this process,however,requires assessing how nurse plants influence the establishment of other species,as well as the proportion of species in the regional species pool that would benefit from the presence of nurse plants in human-disturbed ***,since vegetation recovery is a time-dependent process,the community-level consequences of facilitation are likely to vary among landscapes with different disturbance ***,an integrative perspective of the relevance of nurse plants for vegetation recovery could be obtained by measuring their effects across different human-disturbed landscapes of the target *** study focuses on these issues and uses a regional-scale approach to assess the community-level effects of a widespread nurse plant of American deserts,the creosotebush(Larrea tridentata).Methods This study was conducted in the southernmost portion of Chihuahuan Desert because most floodplain valleys of this region have been affected by human activities during the past *** this study,we selected 10 floodplain valleys differing in their age(*** time elapsed after human activities were ceased).At each landscape,we measured the cover of creosotebushes and the proportion of plant species positively associated with them,as well as the density of seeds in the soil beneath creosotebush *** these data were regressed against the age of the ***,to assess whether positive association patterns were due to facilitation or other processes,we conducted field experiments and measured the ecophysiological performance of plant species established beneath and outside creosotebush *** Findings Most plant species from the target region were positively associated to creosotebushes,and our field

关键词： Chihuahuan desert community-level effects community succession positive interactions Mexico

A one-step,tunable method of selective reactive sputter deposition as a wrinkling approach for silver/polydimethylsiloxane for electrically conductive pliable surfaces

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Microsystems & Nanoengineering 2022年第4期8卷 221-231页

作者： joel Y.Y.Loh Ali zeineddine Moein Shayegannia Robyn McNeil Liam McRae Nazir P.Kherani Department of Electrical and Computing Engineering University of TorontoTorontoON M5S 3G4Canada Department of Material Science and Engineering University of TorontoTorontoON M5S 3E4Canada

The wrinkle period and morphology of a metal thin film on an elastic substrate is typically controlled by modifying the substrate before carrying out additional metal deposition ***,we show that a simultaneously selective and reactive sputtering plasma that modifies the surface of a polydimethylsiloxane(PDMS)substrate while not reacting with the metal during the deposition process decreases the wrinkle wavelength and induces additional wrinkling components and features such as ripples or *** selective reaction of the nitrogen plasma with PDMS functionalizes the siloxane surface into silicon *** hardens the immediate surface of PDMS,with a quadratic increase in the Young’s modulus as a function of the sputtering flow *** increase in the critical strain mismatch and the corresponding presence of folds in the nitrogen-modified wrinkled silver film form a suitable plasmonic platform for surface-enhanced Raman spectroscopy(SERS),yielding an enhancement factor of 4.8×105 for detecting *** enhancement is linked to the emergence of electromagnetic hotspots from surface plasmon polariton coupling between the folds/wrinkles,which in turn enables the detection of low concentrations of organics using ***,when strained,the nitrogen-modified wrinkles enhance electrical conductivity by a factor of 12 compared with unmodified ***,the optical properties of the substrate can be tuned by altering the N2 *** simple addition of nonreactive nitrogen to silver sputtering enables simultaneous PDMS hardening and growth of the silver film and together provide a new avenue for tuning wrinkling parameters and enhancing the electrical conductivity of pliable surfaces.

关键词： silver reactive film

Synthesis and Crystal Structure of tert-Butyl(((2R,3R,6R)-3-hydroxy-6-(nitromethyl)-3,6-dihydro-2H-pyran-2-yl)methyl)carbonate

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Chinese Journal of Structural Chemistry 2021年第9期40卷 1205-1212,1110页

作者： FENG Yong-Kui SU Hua-Lan MUKULA OTUKOL Billy joel zHANG Xue-Qing YAO Hui HUANG Nian-Yu Hubei Key Laboratory of Natural Products Research and Development Key Laboratory of Functional Yeast(China National Light Industry)College of Biological and Pharmaceutical SciencesChina Three Gorges UniversityTichangHubei 443002China

In this paper,aβ-C-pyranogalactoside(Ⅸ)was synthesized from D-galactose through a nine-step reaction with a total yield of 32%under the palladium catalyst,and its structure was characterized by nuclear magnetic resonance(NMR)and high-resolution electrospray ionization mass spectrometry(HR-ESI-MS).The absolute configuration of this pyranogalactoside was confirmed with a Flack parameter of–0.01(6)by X-ray crystallography using a Cu radiation ***(Ⅸ),C_(12)H_(19)NO_(7),crystal data:monoclinic system,space group P2_(1)2_(1)2_(1),a=8.53480(10),b=9.4207(2),c=18.1308(3)A,V=1457.79(4)A^(3),z=4,F(000)=616,Dc=1.318 g/cm^(3),μ=0.931 mm^(-1),R=0.0294 and wR=0.0752 for 2875 independent reflections(R_(int)=0.0163)and 2857 observed ones(I>2σ(I)).

关键词： X-ray diffraction crystal structure absolute configuration β-C-pyranogalactoside α-glucosidase inhibitory activity

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Adaptive Thermoforming and Structural Design of Millimeter-Wave Antenna Panels

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Nanomanufacturing and Metrology 2022年第4期5卷 327-335页

作者： zack Hatfield Alex St.Peter Christian Davila-Peralta joel Berkson Daewook Kim Justin Hyatt James C.Wyant College of Optical Sciences University of Arizona1630 E.University BlvdTucsonAZ85721USA Department of Astronomy and Steward Observatory University of Arizona933 N.Cherry AveTucsonAZ85721USA

Future large-scale radio telescope observatories,such as the next-generation Very Large Array,involve extremely large collection *** collection areas are divided into smaller shaped panels,which typically require their own unique molds to *** these projects to be cost-effective,an efficient fabrication method for the shaped panels is *** paper outlines the development and success of a novel adaptive freeform panel molding technology that greatly improves manufacturing efficiency due to its repeatable and reusable ***,it presents an analysis of a proposed panel structural design for the shaped panels,which incorporates a study on surface deformation due to gravity and wind loading under realistic operational conditions.

关键词： Radio telescope Millimeter-wave Thermoform Adaptable mold

Spontaneous Tumor Lysis Syndrome and Secondary Thrombotic Thrombocytopenic Purpura in Early Stage Colorectal Cancer

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Chinese Journal of Clinical Oncology 2008年第2期5卷 150-153页

作者： Saad Usmani joel Appel zainab Shahid Husain Saleh Hematology-Oncology University of Connecticut Health Center Department of Internal Medicine/HematologyOncology Sinai-Grace HospitalWayne State University Department of Internal Medicine Sinai-Grace Hospital/Detroit Medical CenterWayneState University Department of Pathology Sinai-Grace Hos-pital/Detroit Medical CenterAssociate Pro-fessor of PathologyWayne State University

Introduction Acute tumor lysis syndrome （ATLS） is a well-described oncological emergency that is usually associated with hematological malignancies complicated by treatment. It is typically related to a high tumor burden, rapidly growing and chemosensitive malignancies. ATLS is characterized by the presence of hyperphosphatemia, hyperuricemia, hyperkalemia, hypocalcemia and acute renal failure. The administration of cytotoxic chemotherapy causes tumor death and tissue necrosis which leads to release of inflammatory mediators precipitating this syndrome. However, it has been rarely reported in hematological malignancies without administration of chemotherapy, and has been referred to as spontaneous tumor lysis syndrome （STLS）. STLS is even more infrequent in solid tumors.

关键词： tumor lysis syndrome thrombotic thrombocytopenic purpura colorectal cancer acute renal failure.

Structure and magnetostructural correlation of ferrimagnetic meso-tetraphenylporphinatomanganese(Ⅲ) dimethyl- N,N′-dicyanoquinone diiminide, [MnTPP]^+[Me_2DCNQI]^(.-)

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Science China Chemistry 2012年第6期55卷 987-996页

作者： Jordan L. Arthur Saul H. Lapidus Peter W. Stephens joel S. Miller Department of Chemistry University of Utah Salt Lake City Utah 84112-0850 USA Department of Physics & Astronomy Stony Brook University Stony Brook NY 11794-3800 USA Photon Sciences Directorate Brookhaven National Laboratory Upton NY 11973 USA

The structure [MnmTPP][Me2DCNQI] （TPP = tetraphenylporphinato; Me2DCNQI = 2,5-dimethyl-N,N＇-dicyanoquinonediimine） has been determined from X-ray powder diffraction data. The nonsolvated structure is composed of linear （I-D） chains of alternating [MnmTPP]＋ and ta-[MezDCNQI]＇- with intrachain Mn...Mn separations of 12.83 A, and a Mn-NDcNQI distance of 2.18A. The dihedral angle between the mean Mn（N4）xpp and [MezDCNQI]＇-planes, and the Mn-（N-C）ocNQ1 angle are 84.18° and 143.6°, respectively. [MnInTpP][MezDCNQI] has a Tc of 4.3 K from the 10 Hz x（T） data, 2-K coercivity of 5,600 Oe, and 6,300 emuOe/mol remnant magnetization that are reduced from that observed for related materials, and their in- clusion extends the magnetostructural correlation between the intrachain coupling and both the dihedral angle between the mean Mn（N4）xPp and [TCNE]＇-（TCNE --- tetracyanoethylene） planes and Mn-（N-C）Tcr angles. This is in accord with the in- trachain coupling arising from the overlap of the Mnm dz2-1ike singly occupied molecular orbital （SOMO） and the z component of the [TCNE]- π＊（π2＊） SOMO, which increases with decreasing dihedral angle between the mean Mn（N4）xep and [TCNE]＇- planes and Mn-（N-C）TcNE angle.

关键词： metalloporphyrin magnetic ordering ferrimagnet crystal structure