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The onset of deep recycling of supracrustal materials at the Paleo-Mesoarchean boundary

National science Review 2022年第3期9卷 110-118页

作者： Xiaolei Wang Ming Tang Jeff Moyen Di Wang Alfred kr?ner Chris Hawkesworth Xiaoping Xia Hangqiang Xie Carl Anhaeusser Axel Hofmann Junyong Li Linsen Li state Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University school of Earth and space sciences Peking University Laboratoire Magmas et Volcans UMR6524 Université de LyonUJM-UCA-CNRS-IRD Institut für Geowissenschaften Universit?t Mainz Department of Earth sciences University of Bristol state Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences sHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Economic Geology Research Unit University of the Witwatersrand Department of Geology University of Johannesburg

The recycling of supracrustal materials, and in particular hydrated rocks, has a profound impact on mantle composition and thus on the formation of continental crust, because water modifies the physical properties of lithological systems and the mechanisms of partial melting and fractional fractionation. On the modern Earth, plate tectonics offers an efficient mechanism for mass transport from the Earth’s surface to its interior, but how far this mechanism dates back in the Earth’s history is still uncertain. Here, we use zircon oxygen(O) isotopes to track recycling of supracrustal materials into the magma sources of early Archean igneous suites from the Kaapvaal Craton, southern Africa. The mean δ18O values of zircon from TTG(tonalite–trondhjemite–granodiorite) rocks abruptly increase at the Paleo-Mesoarchean boundary(ca.3230 million years ago; Ma), from mantle zircon values of 5‰–6‰ to approaching 7.1‰, and this increase occurs in ≤3230 Ma rocks with elevated Dy/Yb ratios. The18O enrichment is a unique signature of low-temperature water–rock interaction on the Earth’s surface. Because the later phase was emplaced into the same crustal level as the older one and TTG magmas would derive from melting processes in the garnet stability field(>40 km depth), we suggest that this evident shift in TTG zircon O isotopic compositions records the onset of recycling of the mafic oceanic crust that underwent seawater hydrothermal alteration at low temperature. The onset of the enhanced recycling of supracrustal materials may also have developed elsewhere in other Archean cratons and reflects a significant change in the tectonic realm during craton formation and stabilization, which may be important processes for the operation of plate tectonics on early Earth.

关键词： zircon oxygen isotopes TTG plate tectonics deep recycling Paleo-Mesoarchean boundary

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Modelling the site index of Pinus pinaster plantations in Turkey using ecological variables

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Journal of Forestry Research 2021年第2期32卷 589-598页

作者： Cezmi Özel ŞükrüTeoman Güner Mehmet Türkkan selda Akgül Özdemir Şentürk Research Institute for Forest soil and Ecology EskisehirTurkey southwest Anatolian Forest Research Institute AntalyaTurkey Poplar and Fast Growing Forest Trees Research Institute KocaeliTurkey Gölhisar Vocational school Burdur Mehmet Akif Ersoy UniversityBurdurTurkey

The determination of site productivity in forest ecosystems plays a crucial role in resource *** study was carried out to identify relationships between site characteristics and height growth of Corsican maritime pine(Pinus pinaster Ait.)plantations in ***-nine sample plots>20 years of age were selected from locations with different inclinations,aspects,elevations,slope positions and site *** samples were taken at various *** and age were measured on a dominant tree after felling in each *** and chemical properties of the soil were *** between site index(sI 25)and physiographic factors,climatic attributes as well as soil properties were evaluated using correlation analysis and multiple regression *** index was significantly related with annual precipitation,mean spring rainfall,rainfall June to september,rainfall of the driest month,length of the dry period,mean maximum temperature,mean temperature of the warmest month,stoniness of the soil,sand,silt,clay,pH,electrical conductivity,and available water *** regression accounted for 57.9%of variations in height *** models obtained can be used to determine the site index of potential areas in Turkey for maritime *** can be said that the productivity of maritime pine may decline in the future due to global climate change.

关键词： Pinus pinaster Afforestation Ecology site index

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Mesozoic and Cenozoic microbiotas from eastern Antarctic Peninsula: adaptation to a changing palaeoenvironment

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Advances in Polar science 2019年第3期30卷 165-185页

作者： Cecilia R.AMENábar Andrea CARAMés susana ADAMONIs Ana DOLDAN Gabriel MACEIRAs Andrea CONCHEYRO Instituto de Estudios Andinos"Don Pablo Groeber".Consejo Nacional de Investigaciones Científicas y Técnicas.Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires.Pabellón II.Ciudad Universitaria Departamento de Ciencias Geológicas Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires Instituto Antártico Argentino

A compiled selected literature on some groups of microfossils of the Mesozoic and Cenozoic of the James Ross Basin,eastern Antarctic Peninsula,is presented here,in order to show how the microbiota has been modified over time,triggered by environmental *** analyzed microfossils consist of palynomorphs(mostly pollen grains,spores,and dinoflagellate cysts),foraminifers and *** cysts and pollen-spores have been recorded in Jurassic to Pleistocene sedimentary *** cysts proved to be good indicators for productivity and/or nutrient availability,surface water temperature and chemistry,the position of ancient shorelines and paleoceanographic *** and spores allowed reconstruction of floral community and thus characterization of the climate that prevailed on the ***,recovered from the Lower Cretaceous to the Pleistocene sedimentary rocks,provided information about the bathymetry,showing different marine settings(e.g.,coastal,inner neritic,outer neritic,upper bathyal)in different *** bryozoan record is restricted to the *** colonial growth-forms reflect several environmental conditions such as shallow waters with a low rate of sedimentation,hard substrate and moderate or strong current action for the analyzed *** study of the Antarctic ecosystems based on the fossil microbiota and their response to the climate and the continental configuration changes,allowed understanding of the composition and dynamics of the polar environments,which have an important role in the Earth climate.

关键词： pollen-spores dinoflagellate cysts foraminifers bryozoans palaeoenvironment Mesozoic-Cenozoic James Ross Basin Antarctic Peninsula

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Discrete GWO Optimized Data Aggregation for Reducing Transmission Rate in IoT

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Computer systems science & Engineering 2023年第3期44卷 1869-1880页

作者： s.siamala Devi K.Venkatachalam Yunyoung Nam Mohamed Abouhawwash Department of Computer science and Engineering Sri Krishna College of TechnologyCoimbatore641042India Department of Applied Cybernetics Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic Department of Computer science and Engineering Soonchunhyang UniversityAsan31538Korea Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast LansingMI48824USA

The conventional hospital environment is transformed into digital transformation that focuses on patient centric remote approach through advanced *** diagnosis of many diseases will improve the patient *** cost of health care systems is reduced due to the use of advanced technologies such as Internet of Things(IoT),Wireless sensor Networks(WsN),Embedded systems,Deep learning approaches and Optimization and aggregation *** data generated through these technologies will demand the bandwidth,data rate,latency of the *** this proposed work,efficient discrete grey wolf optimization(DGWO)based data aggregation scheme using Elliptic curve Elgamal with Message Authentication code(ECEMAC)has been used to aggregate the parameters generated from the wearable sensor devices of the *** nodes that are far away from edge node will forward the data to its neighbor cluster head using *** scheme will reduce the number of transmissions over the *** aggregated data are preprocessed at edge node to remove the noise for better *** node will reduce the overhead of cloud *** aggregated data are forward to cloud server for central storage and *** proposed smart diagnosis will reduce the transmission cost through aggrega-tion scheme which will reduce the energy of the *** cost for proposed system for 300 nodes is 0.34μ*** energy cost of existing approaches such as secure privacy preserving data aggregation scheme(sPPDA),concealed data aggregation scheme for multiple application(CDAMA)and secure aggregation scheme(AsAs)are 1.3μJ,0.81μJ and 0.51μJ *** optimization approaches and encryption method will ensure the data privacy.

关键词： Discrete grey wolf optimization data aggregation cloud computing IoT WsN smart healthcare elliptic curve elgamal energy optimization

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soil Microbial Dynamics Modeling in Fluctuating Ecological situations by Using subtractive Clustering and Fuzzy Rule-Based Inference systems

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Computer Modeling in Engineering & sciences 2017年第4期113卷 443-459页

作者： sunil kr.Jha Zulfiqar Ahmad school of Computer and software Nanjing University of Information Science and TechnologyNanjing 210044China Department of Environmental sciences University of CaliforniaRiversideCA 92521USA

Microbial population and enzyme activities are the significant indicators of soil *** microbial dynamics characterize microbial population and enzyme *** present study explores the development of efficient predictive modeling systems for the estimation of specific soil microbial dynamics,like rock phosphate solubilization,bacterial population,and ACC-deaminase *** specifically,optimized subtractive clustering(sC)and Wang and Mendel's(WM)fuzzy inference systems(FIs)have been implemented with the objective to achieve the best estimation accuracy of microbial *** measurements were performed using controlled pot experiment using minimal salt media with rock phosphate as sole carbon source inoculated with phosphate solubilizing microorganism in order to estimate rock phosphate solubilization potential of selected *** experimental parameters,including temperature,pH,and incubation period have been used as inputs sC-FIs and *** better performance of the sC-FIs has been observed as compared to the WM-FIs in the estimation of phosphate solubilization and bacterial population with the maximum value of the coefficient of determination(0.9988)2 R=in the estimation of previous microbial dynamics.

关键词： Phosphate solubilizing bacteria bacterial population ACC-deaminase activity subtractive clustering fuzzy rule-based prediction system

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Multicriteria to estimate the environmental risk of sediment from the Obedska Bog(Northern serbia),a reservation area on UNEsCO's list

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International Journal of sediment Research 2020年第5期35卷 527-539页

作者： Dejan kr?mar Nenad Grba Marijana kragulj Isakovski Nata?a Varga Jelena spasojevi? Jasmina Agbaba Bozo Du?an Dalmacija University of Novi sad Faculty of sciences Department of ChemistryBiochemistry and Environmental Protection

The objective of this current study is to compare related sediment legislation standards and norms to the diversity and influence of anthropogenic and natural(geogenic) sources of pollution in the investigated fluvial relief test site region of the Obedska *** metals(nickel(Ni).zinc(Zn),cadmium(Cd),copper(Cu) and lead(Pb) except chromium(Cr)) and arsenic(As) have higher values than the Upper Continental Crust(UCC) for loess *** sharp leaps in the enrichment factor(r) suggested "indicators of anthropogenic metal pollution" for Cd,Cu(r> 5.0) and Zn,Ni(r> 1.0) for this *** addition,the Chemical Proxy of Alteration(CPA,60-95) from the unique Jadar block terrane and neighbouring representative catchment areas,confirmed moderate to higher intensity of *** Component Analysis/Factor Analysis(PCA/FA) and cluster analysis suggest that Ni,Zn,Cu and Cd are derived from several anthropogenic sources,whereas As is convincingly of geogenic origin,and Pb and Cr exhibit dual *** sum of 16 *** Protection Agency Polycyclic Aromatic Hydrocarbons(EPA PAHs) indicated heterogenic sources,but minor effects to *** results of the current investigation indicated intensive and highly diffuse sources of pollution in this United Nations Educational,scientific and Cultural Organization [UNEsCO's] *** outcomes indicate that Cu should be added to the European Union [EU] watch list of emerging contaminants.

关键词： Priority substances in sediment Contamination criteria Multivariate statistical techniques Heterogeneous sources

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A novel multi-shot target platform for laser-driven laboratory astrophysics experiments

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High Power Laser science and Engineering 2023年第2期11卷 11-19页

作者： Pablo Perez-Martin Irene Prencipe Manfred sobiella Fabian Donat Ning Kang Zhiyu He Huiya Liu Lei Ren Zhiyong Xie Jun Xiong Yan Zhang Florian-Emanuel Brack MichalČervenák Pavel Gajdoš Lenka Hronová Kakolee Kaniz Michaela Kozlová Florian kroll Xiayun Pan Gabriel schaumann sushil singh MichalŠmíd Francisco suzuki-Vidal Panzheng Zhang Jinren sun Jianqiang Zhu Miroslav krůs Katerina Falk Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiation PhysicsDresdenGermany Technische Universität Dresden DresdenGermany Key Laboratory of High Power Laser and Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina shanghai Institute of Laser Plasma China Academy of Engineering PhysicsShanghaiChina Institute of Plasma Physics Czech Academy of SciencesPragueCzech Republic Czech Technical University Faculty of Nuclear Sciences and Physical EngineeringPragueCzech Republic Department of Physics Jagannath UniversityDhakaBangladesh ELI-Beamlines Institute of PhysicsCzech Academy of SciencesPragueCzech Republic Institute for Nuclear Physics Technical University of DarmstadtDarmstadtGermany Institute of Physics Czech Academy of SciencesPragueCzech Republic Blackett Laboratory Imperial CollegeLondonUnited Kingdom First Light Fusion Oxford Industrial ParkYarntonOxfordUnited Kingdom

A new approach to target development for laboratory astrophysics experiments at high-power laser facilities is *** the dawn of high-power lasers,laboratory astrophysics has emerged as a field,bringing insight into physical processes in astrophysical objects,such as the formation of *** important factor for success in these experiments is *** date,targets have mainly relied on expensive and challenging microfabrication *** design presented incorporates replaceable machined parts that assemble into a structure that defines the experimental *** can make targets cheaper and faster to manufacture,while maintaining robustness and *** platform is intended for experiments on plasma flows,but it is flexible and may be adapted to the constraints of other experimental *** of targets used in experimental campaigns are shown,including a design for insertion in a high magnetic field *** results are included,demonstrating the performance of the targets.

关键词： high magnetic fields laboratory astrophysics laser-plasma interaction magnetized plasmas target design

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Effect of Under Connected Plates on the Hydrodynamic Efficiency of the Floating Breakwater

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China Ocean Engineering 2014年第3期28卷 349-362页

作者： A.s.Koraim O.s.Rageh Water and Water structure Engineering Department Faculty of EngineeringZagazig University Irrigation and Hydraulics Department Faculty of Engineering El-Mansoura University

In this paper, the hydrodynamic efficiency of a floating breakwater system is experimentally studied by use of physical models. Regular waves with wide ranges of wave heights and periods are tested. The efficiency of the breakwater is presented as a function of the wave transmission, reflection, and energy dissipation coefficients. Different parameters affecting the breakwater efficiency are investigated, e.g. the number of the under connected vertical plates, the length of the mooring wire, and the wave length. It is found that, the transmission coefficient kt decreases with the increase of the relative breakwater width B/L, the number of plates n and the relative wire length l/h, while the reflection coefficient kr takes the opposite trend. Therefore, it is possible to achieve kt values smaller than 0.25 and kr values larger than 0.80 when B/L is larger than 0.25 for the case of l/h-1.5 and n=4. In addition, empirical equations used for estimating the transmission and reflection coefficients are developed by using the dimensionless analysis, regression analysis and measured data and verified by different theoretical and experimental results.

关键词： floating breakwaters vertical plates regular waves transmission reflection energy dissipation

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Hydrodynamic Performance of Vertical Porous structures Under Regular Waves

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China Ocean Engineering 2013年第4期27卷 451-468页

作者： A.s.Koraim O.s.Rageh Water and Water structure Eng. Dept. Faculty of Eng. Zagazig University Irrigation and Hydraulics Dept. Faculty of Eng. El-Mansoura University

The hydrodynamic efficiency of the vertical porous structures is investigated under regular waves by use of physical models. The hydrodynamic efficiency of the breakwater is presented in terms of the wave transmission （kt）, reflection （kr） and energy dissipation （ka） coefficients. Different wave and structural parameters affecting the breakwater efficiency are tested. It is found that, the transmission coefficient （kt） decreases with the increase of the relative water depth （h/L）, the wave steepness （Hi^L）, the relative breakwater widths （B/L, B/h）, the relative breakwater height （D/h）, and the breakwater porosity （n）. The reflection coefficient （kr） takes the opposite trend of kt when D/h=l.25 and it decreases with the increasing h/L, HJL and B/L when D/h〈1.0. The dissipation coefficient （kd） increases with the increasing h/L, HilL and B/L when D/h〈_l.O and it decreases when D/h=l.25. In which, it is possible to achieve values ofkt smaller than 0.3, k~ larger than 0.5, and kd larger than 0.6 when D/h=1.25, B/h=0.6, h/L〉0.22, B/L〉O. 13, and H/L 〉0.04. Empirical equations are developed for the estimation of the transmission and reflection coefficients. The results of these equations are compared with other experimental and theoretical results and a reasonable agreement is obtained.

关键词： water waves porous breakwaters wave attenuation wave transmission wave reflection wave dissipation

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Chiral synthesis of the Key Intermediate of Diterpenoids

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Chinese Chemical Letters 1997年第11期8卷 949-950页

作者： Hao, XJ Node, MB Fuji, kr Chinese Acad sci Kunming Inst Bot Kunming 650204 Peoples R China Kyoto Pharmaceut Univ Yamashima Ku Kyoto 607 Japan Kyoto Univ Inst Chem Res Uji 611 Japan

(-)-Methyl(4R, 5s, 10R)-14-methoxypodocarpa-8, 11, 13-triene-19-oate(1), which is the key intermediate for synthesis of diterpenoids, was synthesized from (R)-(+)-2-methyl-2-(2`-nitrovinyl)-delta-valerolactone(2).

关键词： ADDITION ELIMINATION PROCEss NITROOLEFINATION LACTONEs

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