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Acta Geologica Sinica(English Edition) 2001年第1期75卷 41-50页

作者： ZHANG Zhaochong MAO jingwen ZUO Guochao YANG jianmin Paul t.ROBINSON Institute of Geology Chinese Academy of Geological SciencesBaiwanzhuang Road 26Beijing 100037China Institute of Mineral Deposits Chinese Academy of Geological SciencesBaiwanzhuang Road 26Beijing 100037China Institute of Geology Gansu Bureau of Geology and Mineral ResourcesLanzhou 730000China Centre For Marine Geology Dalhousie UniversityHalifaxNova ScotiaB3H 3J5Canada

the Aoyougou ophiolite lies in an early Palaeozoic orogenic belt of the western North Qilian Mountains, near the Aoyougou valley in Gansu Province, northwestern China. It consists of serpentinite, a cumulate sequence of gabbro and diorite, pillow and massive lavas, diabase and chert. Ages of 1840±2 Ma, 1783±2 Ma and 1784±2 Ma on three zircons from diabase, indicate an early Middle Proterozoic age. the diabases and basalts show light rare-earth element enrichment and have relatively high tiO2 contents, characteristic of ocean island basalts. All of the lavas have low MgO, Cr, Ni contents and Mg numbers indicating a more evolved character. they are believed to have been derived from a more mafic parental magma by fractionation of olivine, Cr-spinel and minor plagioclase. Based on the lava geochemistry and regional geology, the Aoyougou ophiolite was probably believed to have formed at a spreading centre in a small marginal basin. Subduction of the newly formed oceanic lithosphere in the Middle Proterozoic produced a trench-arc-basin system, which is preserved in the North Qilian Mountains.

关键词： Proterozoic ophiolite geochronology geochemistry North Qilian Mountains

Preventing Pressure Oscillations Does Not Fix Local Linear Stability Issues of Entropy-Based Split-Form High-Order Schemes

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Communications on Applied Mathematics and Computation 2022年第3期4卷 880-903页

作者： Hendrik Ranocha Gregor j.Gassner Applied Mathematics Münster University of Münster48149 MünsterGermany Computer Electrical and Mathematical Science and Engineering(CEMSE)Division King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia Department of Mathematics and Computer Science Center for Data and Simulation ScienceUniversity of CologneCologneGermany

Recently,it was discovered that the entropy-conserving/dissipative high-order split-form discontinuous Galerkin discretizations have robustness issues when trying to solve the sim-ple density wave propagation example for the compressible Euler *** issue is related to missing local linear stability,i.e.,the stability of the discretization towards per-turbations added to a stable base *** is strongly related to an anti-diffusion mech-anism,that is inherent in entropy-conserving two-point fluxes,which are a key ingredi-ent for the high-order discontinuous Galerkin *** this paper,we investigate if pressure equilibrium preservation is a remedy to these recently found local linear stability issues of entropy-conservative/dissipative high-order split-form discontinuous Galerkin methods for the compressible Euler *** equilibrium preservation describes the property of a discretization to keep pressure and velocity constant for pure density wave *** present the full theoretical derivation,analysis,and show corresponding numerical results to underline our *** addition,we characterize numerical fluxes for the Euler equations that are entropy-conservative,kinetic-energy-preserving,pressure-equilibrium-preserving,and have a density flux that does not depend on the *** source code to reproduce all numerical experiments presented in this article is available online(https://***/10.5281/zenodo.4054366).

关键词： Entropy conservation Kinetic energy preservation Pressure equilibrium preservation Compressible Euler equations Local linear stability Summation-by-parts

Encapsulation of superparamagnetic Fe_3O_4@SiO_2 core/shell nanoparticles in MnO_2 microflowers with high surface areas

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Chinese Chemical Letters 2015年第2期26卷 233-237页

作者： Yu-Gang Sun tu t.truong Yu-Zi Liu Yong-Xing Hu Center for Nanoscale Materials Argonne National Laboratory

Microflowers made of interconnected MnO2 nanosheets have been successfully synthesized in a microwave reactor through a hydrothermal reduction of KMnO4 with aqueous HCI at elevated temperatures in the presence of superparamagnetic Fe3O4SiO2 core-shell *** to the chemical compatibility between SiO2 and MnO2,the heterogeneous reaction leads to the spontaneous encapsulation of the Fe3O4@SiO2 core-shell nanoparticles in the MnO2 *** resulting hybrid particles exhibit multiple properties including high surface area associated with the MnO2nanosheets and superparamagnetism originated from the Fe3O4@SiO2 core-shell *** are beneficial for applications requiring both high surface area and magnetic separation.

关键词： Microwave synthesis Manganese oxide nanosheets Superparamagnetic nanoparticles Hybrid nanostructures Multifunctional nanostructures

Iodide-selective polymeric membrane electrode based on copper(Ⅱ) bis(N-2-bromophenylsalicyldenaminato) complex

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Chinese Chemical Letters 2011年第9期22卷 1087-1090页

作者： Ali Benvidi M.t.Ghanbarzadeh M.Mazloum-Ardakani R.Vafazadeh Department of Chemistry Yazd UniversityYazdIran

A PVC membrane electrode based on copper（II） bis（N-2-bromophenylsalicyldenaminato） as ionophor was prepared. the ion selective electrode was tested by inorganic anions and showed a good selectivity for iodide ion. this sensor exhibited Nernstian behavior with a slope of -57.8 mV per decade at 25℃. the proposed electrode showed a linear range from 1.0 × 10 ^-5 to 1.0 × 10 ^-1 mol/L with a detection limit of 5.0 × 10 ^-6 mol/L. the electrode response was independent of pH in the range of 3.0- 10.0. the proposed sensor was applied to determine the iodide in water and antiseptic samples.

关键词： Iodide-selective electrode Polymeric membrane Potentimetry

Experimental Study of the Atomic and Molecular Processes Related to Plasma Detachment in Steady-State Divertor Simulator MAP-Ⅱ

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Plasma Science and technology 2004年第5期6卷 2451-2455页

作者： S.Kado S.Kajita Y.Iida B.Xiao t.Shikama D.Yamasaki t.Oishi S.taraka High temperature Plasma Center The University of Tokyo2-11-16 YayoiBunkyo-kuTokyo 113-8656 JapanGraduate School of EngineeringThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo1138656 JapanGraduate School of EngineeringThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo1138656 JapanHigh Temperature Plasma CenterThe University of Tokyo2-11-16 YayoiBunkyo-kuInstitute of Plasma PhysicsChinese Academy of SciencesHefei 230031ChinaGraduateGraduateGraduateGraduate School of EngineeringThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo113-8656 JapanSchool of EngineeringThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo113-8656 JapanSchool of EngineeringThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo113-8656 JapanSchool of EngineeringThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo113-8656 Japan

Atomic and molecular processes relevant to the volumetric recombinationphenomena were investigated in a linear divertor plasma simulator MAP-Ⅱ. Volumetric recombinationis induced in He plasma by puffing of He or H_2. In the He puffing case, the reduction of the ionflux is dominated by the electron-ion recombination. In the H_2 puffing case, however, it isdominated by the molecule-assisted recombination (MAR), which is characterized by the disappearanceof the Helium Rydberg spectra and by the existence of the hydrogen negative ions. Currentachievement and the future prospect are described.

关键词： divertor plasma simulator MAP-Ⅱ molecular assisted recombination heliumrydberg spectra

震源复杂性的常规估计方法——用于1992年10月18日哥伦比亚地震

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世界地震译丛 1995年第6期26卷 20-25页

作者： C.j.Ammon t.Lay A.A.Velasco j.E.Vidale 陈宇卫安徽省地震局

本文介绍两种适用于远震记录的方法,来表征地震事件的时间进程。叠加由大的区域台阵记到的短周期信号可获得震源高频辐射的稳定估计;而对经验格林函数进行反褶积则可获得适用于分析破裂复杂性和破裂时空尺度的可靠的宽带震源时间函数。... 详细信息

本文介绍两种适用于远震记录的方法,来表征地震事件的时间进程。叠加由大的区域台阵记到的短周期信号可获得震源高频辐射的稳定估计;而对经验格林函数进行反褶积则可获得适用于分析破裂复杂性和破裂时空尺度的可靠的宽带震源时间函数。这两种方法相结合就能描述大地震(M_s>7)震源在o.5-200s周期范围的辐射特征。

关键词：地震震源震级常规估计法哥伦比亚

Heavy metal concentrations in soils and plants in the vicinity of Arufu lead-zinc mine, Middle Benue trough, Nigeria

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Chinese journal Of Geochemistry 2010年第2期29卷 167-174页

作者： Nganje t.N. Adamu C.I. Ukpong E.E. Department of Geology University of Calabar Formerly Department of Geology University of Calabar

this study focused on the influence of base metal mining on heavy metal levels in soils and plants in the vicinity of Arufu lead-zinc mine, Nigeria. Soil samples (0-15 cm depth) and plant samples were collected from cul-tivated farmlands in and around the mine, the unmineralized site and a nearby forest (the control site). the samples were analyzed for heavy metals (Fe, Zn, Mn, Cu, Pb, Cr and Cd) by Atomic Absorption Spectrophotometry (AAS). the physical properties of soils (pH and LOI) were also measured. Results showed that soils from cultivated farm-lands have neutral pH values (6.5-7.5), and low organic matter contents (ti-vated soils were higher than the concentrations obtained from the control site. these heavy metals are most probably sourced from mining and agricultural activities in the study area. Heavy metal concentrations measured in plant parts decreased in the order of rice leaves>cassava tubers>peelings. In the same plant species, metal levels decreased in the order of Zn>Fe>Mn>Cu>Pb>Cr>Cd. Most heavy metals were found in plant parts at average concentrations normally observed in plants grown in uncontaminated soil, however, elevated concentrations of Pb and Cd were found in a few cassava samples close to the mine dump. A stepwise linear regression analysis identified soil metal contents, pH and LOI as some of the factors influencing soil-plant metal uptake.

关键词：土壤重金属含量土壤样品植物样本铅锌矿尼日利亚原子吸收光谱法线性回归分析 amp

Spectral reflectance response to nitrogen fertilization in field grown corn

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International journal of Agricultural and Biological Engineering 2018年第4期11卷 118-126页

作者： Chuanqi Xie Ce Yang Alexander Hummel jr Gregg A johnson Forrest t Izuno Department of Bioproducts and Biosystems Engineering University of MinnesotaSaint PaulMN 55108United States Farm Nutrients Inc. 4949 Hwy 71RembrandtIA 50576United States Department of Agronomy and Plant Genetics University of MinnesotaSaint PaulMN 55108United States Southern Research and Outreach Center University of MinnesotaWasecaMN 56093United States

this study was carried out to analyze the spectral reflectance response of different nitrogen levels for corn *** different nitrogen treatments of 0%,80%,100%and 120%BMP(best management practice)were *** component analysis-loading(PCA-loading)was used to identify the effective *** least squares(PLS)and multiple linear regression(MLR)models were built to predict different nitrogen *** indices(VIs)were calculated and then used to build more prediction *** full and selected wavelengths-based models showed similar prediction *** overall PLS model obtained the coefficient of determination(R^(2))of 0.6535 with a root mean square error(RMSE)of 0.2681 in the prediction *** selected wavelengths for overall MLR model obtained the R^(2) of 0.6735 and RMSE of 0.3457 in the prediction *** results showed that the wavelengths in visible and near infrared region(350-1000 nm)performed better than the two either spectral regions(1001-1350/1425-1800 nm and 2000-2400 nm).For each data set,the wavelengths around 555 nm and 730 nm were identified to be the most important to predict nitrogen *** vogelmann red edge index 2(VOG 2)performed the best among all *** demonstrated that spectral reflectance has the potential to be used for analyzing nitrogen response in corn.

关键词： spectrum effective wavelengths principal component analysis-loading(PCA-loading) prediction vegetation indices(VIs) corn

Secondary relaxation and dynamic heterogeneity in metallic glasses：A brief review

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Chinese Physics B 2017年第1期26卷 32-41页

作者： j C Qiao[[ Q Wang D Crespo Y Yang j M Pelletier School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi＇an 710072 China Centre for Advanced Structural Materials Department of Mechanical and Biomedical Engineering City University of Hong Kong Kowloon Tong Kowloon Hong Kong China Universite de Lyon MATEIS UMR CNRS5510 Bat. B. Pascal INSA-Lyon F-69621 Villeurhanne cedex France Key Laboratory for Structures Institute of Materials Science Shanghai University Shanghai 200444 China Departament de Fisica EETAC Universitat Politecnica de Catalunya 08860-Castelldfels Barcelona Spain

Understanding mechanical relaxation, such as primary（α） and secondary（β） relaxation, is key to unravel the intertwined relation between the atomic dynamics and non-equilibrium thermodynamics in metallic glasses. At a fundamental level, relaxation, plastic deformation, glass transition, and crystallization of metallic glasses are intimately linked to each other, which can be related to atomic packing, inter-atomic diffusion, and cooperative atom movement. Conceptually, βrelaxation is usually associated with structural heterogeneities intrinsic to metallic glasses. However, the details of such structural heterogeneities, being masked by the meta-stable disordered long-range structure, are yet to be understood. In this paper, we briefly review the recent experimental and simulation results that were attempted to elucidate structural heterogeneities in metallic glasses within the framework of β relaxation. In particular, we will discuss the correlation amongβ relaxation, structural heterogeneity, and mechanical properties of metallic glasses.

关键词： metallic glass structural heterogeneity mechanical property secondary relaxation

Comment on “Approximate and Conditional teleportation of an Unknown Atomic State Without Bell-State Measurement with two-Photon Interaction”

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Communications in theoretical Physics 2009年第7期52卷 41-44页

作者： A.D.dSouza W.B.Cardoso A.t.Avelar B.Baseia Instituto de Física Universidade Federal de Goiás

In a previous work [Commun. theor. Phys. 45 （2006） 79] a scheme was presented for approximate and conditional teleportation of an unknown atomic state in a QED-cavity without Bell-state measurement via two-photon jaynes-Cummings model in the effective Hamiltonian approach. this comment presents an alternative method, based on the so called ＂full two-photon jaynes-Cummings Hamiltonian approach＂. Accordingly, it describes the evolution of the two-photon degenerate process for arbitrary average photon number inside the cavity, as the correct way to implement teleportation in this scenario.

关键词： teleportation Bell-state measurement cavity QED two-photon interaction