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A Laurentian affinity for the Embu Terrane,Ribeira Belt(SE Brazil),revealed by zircon provenance statistical analysis

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Geoscience Frontiers 2023年第1期14卷 149-161页

作者： Bruno v.Ribeiro Frederico M.Faleiros Ginaldo A.C.Campanha Peter A.Cawood Christopher L.Kirkland Milo Barham Erin L.Martin Marina Seraine Dina I.G.Cabrita Maria T.A.G.Yogi vidyãv.Almeida Anny J.A.Forero-Ortega Elton L.Dantas Timescales of Mineral Systems Group School of Earth and Planetary SciencesCurtin UniversityPerthWA 6102Australia Isotopia Laboratory School of EarthAtmosphere and EnvironmentMonash UniversityClaytonVictoria 3800Australia Department of Mineralogy and Geotectonics University of São PauloRua do Logo 56205508-900 São PauloBrazil Department of Geological Science and Geological Engineering of Queen's University KingstonOntarioCanada Department of Earth Sciences Carleton UniversityOttawaOntarioCanada Geodynamics Division Geological Survey of Brazil(CPRM)Rua Costa 5501304-010 São PauloSPBrazil Institute for Geophysics Pontificia Universidad JaverianaBogotáColombia Institute of Geoscience University of BrasiliaCampus Universitário Darcy RibeiroAna Norte70919-900 BrasiliaDFBrazil

New and compiled detrital zircon U-Pb ages from the southern Neoproterozoic-Cambrian Ribeira Belt,SE Brazil,demonstrate Laurentian affinity of the Embu Terrane which is statistically distinct from the adjoining Apiaíand São Roque terranes with cratonic affinity(e.g.,São Francisco Craton).Zircon provenance results indicate that the type-area of the Embu Terrane is dominated by detrital zircon age modes at ca.1200 Ma,1400 Ma,and 1800 Ma,with maximum depositional age of ca.1000 *** contrast,the Apiaíand São Roque terranes are dominated by Paleoproterozoic detrital zircon ages(ca.2200-2000 Ma age dominant component),with maximum depositional ages of ca.1400 Ma and 1750 Ma,*** scaling(MDS)analysis of non-parametric similarity measurements on zircon age populations indicates for the first time that the Embu Terrane encompass two statistically distinct detrital zircon age spectra,which is also reflected in the metamorphic zircon age *** statistical characterization of the Embu Terrane through populational metrics allow a quantitative comparison with surrounding tectonic domains and rock samples classified such as *** results clearly highlight the distinction between the statistically differentiated Embu Terrane from the Apiaíand São Roque terranes,supporting an allochthonous *** addition,we demonstrate that rocks samples previously classified as Embu-type are significantly dissimilar to the definition of Embu Terrane,failing to support alternative tectonic models(e.g.,intracontinental evolution).Detrital zircon age spectra reveal that the Apiaíand São Roque terranes have similar zircon provenance to domains sourced from the São Francisco Craton,whereas detrital zircon populations from the Embu Terrane have greater affinity with SW Laurentia basins(and their inferred sediment sources),consistent with previous ***,we interpret the Embu Terrane as a Rodinia descendant developed along the active margin o

关键词： Ribeira belt Embu terrane Detrital zircon Multidimensional scaling Rodinia and gondwana Paleogeography

Synthesis and Antibacterial Activity of Urea and Thiourea Derivatives of Anacardic Acid Mixture Isolated from A Natural Product Cashew Nut Shell Liquid (CNSL)

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International Journal of Organic Chemistry 2012年第3期2卷 267-275页

作者： N. Subhakara Reddy A. Srinivas Rao M. Adharvana Chari v. Ravi kumar v. Jyothy v. Himabindu Bio-Pharma Pvt. Ltd. Westren Hills Hyderabad India Centre for Environment Institute of Science and Technology JNT University Hyderabad India Medicinal Chemistry Laboratory GVK Biosciences Pvt. Ltd. Hyderabad India

Synthesis and antibacterial activity of some novel urea and thiourea derivatives (8a - 8k, 9a - 9f) of anacardic acid prepared from commercially available anacardic acid which is obtained from natural product Cashew Nut Shell Liquid (CNSL). Compounds (8a - 8k, 9a - 9f) were tested for Gram positive and Gram negative bacterial cultures. Most of the compounds were showed active compared with standard drug ampicilline.

关键词： Synthesis Urea and Thiourea Derivatives Anacardic Acid Anti-Bacterial Activity

A model for the chain-to-plane charge transfer in YBa_2Cu_3O_(6+x)

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Chinese Physics B 2012年第11期21卷 448-452页

作者： v.M.Matic N.Dj.Lazarov M.Milic Laboratory of Theoretical Physics Institute of Nuclear Sciences"Vinca"Belgrade University

A model for the chain-to-plane charge transfer is proposed to account for the two plateaus, at 60 K and at 90 K, of the Tc（x） characteristics of the YBa2Cu3O6＋x high-Tc superconductor. It is assumed that the number of holes transferred from a CuO chain of length l to two nearby CuO2 sheets is proportional to l （that is, to the number of oxygen atoms in the chain）, if the chain length is greater than, or equal to, a certain critical chain length, lcr, that is required to trigger the charge transfer process. No holes are assumed to have been transferred from chains of length l〈 lcr. The calculated Tc（x） dependence is found to be in excellent agreement with the experimentally reported Tc（x）. The critical chain length parameter is estimated to be equal to lcr = 11 （eleven oxygen atoms in a chain）, which is a greater value than that obtained in the previously proposed model for the chain-to-plane charge transfer （lcr = 4）. The results obtained out of the proposed model are briefly discussed.

关键词： YBCO oxygen ordering critical temperature doping

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振荡波导阵列中孤子的实验发现

Science Bulletin 2023年第18期68卷 2017-2024,M0003页

作者： Antonina A.Arkhipova Yiqi Zhang Yaroslav v.Kartashov Sergei A.Zhuravitskii Nikolay N.Skryabin Ivan v.Dyakonov Alexander A.Kalinkin Sergei P.Kulik victor O.Kompanets Sergey v.Chekalin victor N.Zadkov Institute of Spectroscopy Russian Academy of SciencesTroitsk 108840Russia Faculty of Physics Higher School of EconomicsMoscow 105066Russia Key Laboratory for Physical Electronics and Devices(Ministry of Education) School of Electronic Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Quantum Technology Centre Faculty of PhysicsM.V.Lomonosov Moscow State UniversityMoscow 119991Russia

时间参数周期变化的弗洛凯系统有助于发现常参数静态系统中不存在并常常伴有新颖拓扑态出现的非传统拓扑相.耦合系数被周期调制的Su-Schrieffer-Heeger晶格正是这种弗洛凯系统之一.尽管这个晶格在一半演化周期内处在拓扑非平庸相,在另... 详细信息

时间参数周期变化的弗洛凯系统有助于发现常参数静态系统中不存在并常常伴有新颖拓扑态出现的非传统拓扑相.耦合系数被周期调制的Su-Schrieffer-Heeger晶格正是这种弗洛凯系统之一.尽管这个晶格在一半演化周期内处在拓扑非平庸相,在另一半周期内处于拓扑平庸相,它的边界上仍然支持源于拓扑的反常π模.本文通过在透明非线性光学材料中刻蚀出周期振荡的Su-Schrieffer-Heeger波导阵列,分别实验观测到了一维系统中位于边界和二维系统中位于角落的光学反常π模.同时,在弗洛凯频谱的禁带中,作者还证实了在高功率情况下一类分化自光学反常π模的新拓扑π孤子.本文报道的π孤子是强振荡的非线性弗洛凯态,它们的波形在每经过一个纵向周期后都可以精确地复现.不论是在一维还是在二维振荡波导阵列中,这类π孤子都是动态稳定的,它们的局域特性都由其功率决定.二维的结果还表明作者实现了弗洛凯光学高阶拓扑绝缘体.

关键词： Floquet topological insulators p states Edge solitons SSH model

俄罗斯贝加尔湖北部Yoko-Dovyren层状纯橄岩-橄长岩-辉长岩地块:结构、成分以及作为矿物原材料的用途

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地学前缘 2020年第5期27卷 262-279页

作者： Svetlana S.Timofeeva Evgeniy v.Kislov Lyudmila I.Khudyakova Industrial Ecology and Life Safety Department of Irkutsk National Research Technical University Federal State Budget Educational Institution of Higher EducationIrkutskRussia Laboratory of Geochemistry and Ore Formation Processes Geological Institute of the Siberian Branch of the Russian Academy of SciencesFederal State Budgetary Institution of ScienceUlan-UdeRussia Laboratory of Chemistry and Technology of Natural Raw Materials Baikal Institute of Nature Management of the Siberian Branch of the Russian Academy of SciencesFederal State Budgetary Institution of ScienceUlan-UdeRussia

Yoko-Dovyren层状纯橄岩-橄长岩-辉长岩地块位于西伯利亚克拉通南部的一处褶皱构造框架中(俄罗斯贝加尔湖地区北部)。该地块的结构在其厚度最大的中部得到了着重研究。剖面底部主体成分为斜长橄榄岩,并依据内部的堆晶成分变化从下往上... 详细信息

Yoko-Dovyren层状纯橄岩-橄长岩-辉长岩地块位于西伯利亚克拉通南部的一处褶皱构造框架中(俄罗斯贝加尔湖地区北部)。该地块的结构在其厚度最大的中部得到了着重研究。剖面底部主体成分为斜长橄榄岩,并依据内部的堆晶成分变化从下往上可分为五个主要的地层序列:纯橄岩→橄长岩→橄榄辉长岩→橄榄辉长苏长岩→石英辉长苏长岩以及含易变辉石的辉长岩。该地块的矿化包括铜-镍矿化、低硫型富铂族元素(PGE)矿化以及铬铁矿化等。另外,该地块也含多种非金属矿物原材料,如硼矿化、透辉石、各种镁质硅酸盐岩等。它们也包括纯橄岩、异剥橄榄岩和橄长岩,并以较高的品质产出,有望采掘加工成为建筑材料(水泥、混凝土、沥青混凝土和建筑陶瓷)。综合利用矿物原材料可增加矿床价值,并有助于建设环保型采矿工作体系。

关键词：镁铁质-超镁铁质杂岩 Yoko-Dovyren层状纯橄岩-橄长岩-辉长岩地块铜镍硫化物矿铂族元素成矿作用镁硅酸盐岩石建筑材料

Effect of thermal cycle on Ni-Cr based nanostructured thermal spray coating in boiler tubes

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Transactions of Nonferrous Metals Society of China 2015年第5期25卷 1533-1542页

作者： v.SENTHILKUMAR B.THIYAGARAJAN M.DURAISELvAM K.KARTHICK Department of Production Engineering National Institute of Technology Bharat Heavy Electricals Limited

Ni-Cr based nanostructured feedstock powder was prepared by mechanical milling technique involving repeated welding, fracturing, and re-welding of powder particles in a planetary ball mill. The milled nanocrystalline powders were used to coat carbon steel tubes using high velocity oxygen fuel（HvOF） thermal spraying process. The characterization of the feedstock powder and HvOF coated substrates was performed using optical microscope, X-ray diffractometer（XRD）, scanning electron microscope（SEM）, high resolution transmission electron microscope（HR-TEM）, energy dispersive spectrometer（EDS） and microhardness tests. The coated and uncoated samples were subjected to different thermal cycles and characterized for their phase changes, metallurgical changes and microhardness variations. Ni-Cr nanostructured coated samples exhibited higher mechanical and metallurgical properties compared to their conventionally coated counter parts. The results showed that the nanostructured coating possessed a more uniform and denser microstructure than the conventional coating.

关键词： nanostructure coating feedstock powder thermal spray boiler tubes high velocity oxygen fuel

Separation and purification of tantalum from plumbomicrolite of amazonite deposit in Kola Peninsula by acid leaching and solvent extraction

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Journal of Central South University 2021年第1期28卷 72-88页

作者： S M MASLOBOEvA L G ARUTYUNYAN M N PALATNIKOv D v MANUKOvSKAYA Tananaev Institute of Chemistry–Subdivision of the Federal Research Centre Kola Science Centre of the Russian Academy of SciencesApatity 184209Russia

A plumbomicrolite concentrate(PMC)was leached with the mixture of HF and H2SO4,HF and HNO3 acids,*** conditions ensuring high recovery of tantalum and niobium(up to 99%)into solution,and radionuclides into insoluble residue were ***-sulfuric acid and fluoride-nitric acid schemes were proposed for PMC leaching by an extractive separation of tantalum form niobium,lead and impurities,and production of high-purity tantalum ***-1 was used as an *** conditions for production of high-purity tantalum strip solutions were defined for all stages(extraction-scrubbing-stripping).Produced tantalum compounds,such as tantalum pentoxide and potassium heptafluotanthalate,comply with the norms for high-purity substances in terms of impurities *** choice of the PMC processing scheme is determined by its profitability.

关键词： mineral plumbomicrolite tantalum niobium acid leaching radioactivity solvent extraction

The Applicability of Fluid Model to Electrical Breakdown and Glow Discharge Modeling in Argon

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Chinese Physics Letters 2015年第2期32卷 81-85页

作者： M. N. Stankov M. D. Petkovic v. Lj. Markovic S. N. Stamenkovic A. P. Jovanovic Department of Physics Faculty of Sciences and Mathematics University of Nis Visegradska 33 Nis18001 Serbia Department of Computer Science Faculty of Sciences and Mathematics University of Nis Visegradska 33 Nig 18001 Serbia

The simple fluid model, an extended fluid model, and the fluid model with nonlocal ionization are applied for the calculations of static breakdown voltages, Paschen curves and current-voltage characteristics. The best agreement with the experimental data for the Paschen curve modeling is achieved by using the model with variable secondary electron yield. The modeling of current-voltage characteristics is performed for different inter-electrode distances and the results are compared with the experimental data. The fluid model with nonlocal ionization shows an excellent agreement for all inter-electrode distances, while the extended fluid model with variable electron transport coefficients agrees well with measurements at short inter-electrode distances when ionization by fast electrons can be neglected.

关键词： PASCHEN-Back effect ARGON ELECTRIC currents ELECTRIC potential ELECTRODES

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气体燃料气动火焰稳定器混合特性的初步研究

推进技术 2019年第12期40卷 2771-2778页

作者：李子万申小明袁怡祥 vARSEGOv v L 肖波图波列夫喀山国立技术大学喷气发动机与动力装置系俄罗斯嘻山市420111 中国科学院工程热物理研究所北京100190 中国科学院大学工程科学学院北京100190

为了克服航空发动机加力燃烧室传统钝体火焰稳定器存在的流阻较大、燃烧效率较低和红外辐射偏大的缺点,设计了一种气体燃料气动火焰稳定器,通过喷射气体燃料射流形成气动屏障来产生回流区从而稳定火焰,并采用数值模拟计算和实验测试的... 详细信息

为了克服航空发动机加力燃烧室传统钝体火焰稳定器存在的流阻较大、燃烧效率较低和红外辐射偏大的缺点,设计了一种气体燃料气动火焰稳定器,通过喷射气体燃料射流形成气动屏障来产生回流区从而稳定火焰,并采用数值模拟计算和实验测试的方法研究了气体燃料火焰稳定器的混合特性。数值模拟计算表明气动火焰稳定器掺混速度快,可在回流区内形成余气系数比较均匀的混合物,且回流区内余气系数分布随来流和射流的参数变化基本保持恒定不变,实验结果证实了数值模拟的结果,并表明采用气动火焰稳定器的燃烧效率较高,部分工况可达98%以上,可为加力燃烧室火焰稳定器的研究和设计提供参考和依据。

关键词：航空发动机气体燃料气动火焰稳定器余气系数燃烧效率