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Soil Formation of "Atlantic Rankers" from NW Spain—A High Resolution Aluminium and Iron Fractionation Study

Pedosphere 2008年第4期18卷 441-453页

作者： J. KAAL M. COSTA-CASAIS C. FERRO-VZQUEZ x. pontevedra-pombal A. MARTINEZ-CORTIZAS Instituto de Estudios Galegos Padre Sarmiento Laboratorio de Arqueología del Paisaje (LAr) IEGPS-CSIC-XuGaRúa San Roque 2 15704 Santiago de Compostela (Spain). Departamento de Edafología y Química Agrícola Fac. Biología Universidad de Santiago (Spain)

Atlantic rankers belong to the group of ＂cryptopodzolic rankers＂, which are ubiquitous in the mountainous cool/temperate humid regions of Western Europe. The rankers of Galicia （NW Spain） formed by thousands of years of colluviation. The preponderance of Al-stabilised organic matter （OM） masks the horizonation and polycyclic character （i.e., stratification） of these soils. Cryptopodzolic rankers are generally thought to be the outcome of podzolisation. This soil type is part of the recent discussion on how to classify soils developed from nonvolcanic parent material having andic properties. To better understand the formation processes of these soils, the Al and Fe fractionation of four typical Atlantic rankers were studied by selective dissolution in acid NH4-ox.late, Na-pyrophosphate and the chlorides of K, La and Cu. A high-resolution sampling approach allowed us to investigate the soils in greater detail than simply sampling by horizon. The rankers studied display a distribution of Fe- and AI-OM complex.s that is typical of cryptopodzolic soils. However, these organomineral associations were probably immobile due to the high Al saturation. We argue that the soils owe their characteristic chemical status to ex.ernal factors rather than to translocation of organomineral associations： variations in AI-OM concentrations could be linked to changes in weathering/leaching intensity and colluviation rates caused by anthropogenic disturbances or changes in regional climate regime.

关键词： Al fractionation colluviation cryptopodzolic soil podzolisation ranker

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Distinct Electrical and Mechanical Responses of a Cu-10Fe Composite Prepared by Hot-Pressed Sintering and Post Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： x.Y.Yue S.Y.Peng x.Zhang C.N.He Y.Z.Tian Key Laboratory for Anisotropy and Tex.ure of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin300350China Research Centre for Metallic Wires Northeastern UniversityShenyang110819China

A Cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the Cu-10wt%Fe *** Cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained ex.ellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IACS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance Cu-based in-situ composites by post treatment.

关键词： Cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

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Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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Matter and Radiation at Ex.remes 2024年第3期9卷 11-18页

作者： Y.x.Wang x.L.Zhu S.M.Weng P.Li x.F.Li H.Ai H.R.Pan Z.M.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index.in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and THz spectral ranges.

关键词： laser ultrashort photon

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Large non-pedunculated colorectal polyp management: The elephant in the room

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World Journal of Gastroenterology 2024年第25期30卷 3126-3131页

作者： Shirley x.Jiang Neal Shahidi Department of Medicine University of British ColumbiaVancouver V6Z 2K5BCCanada

Minimally invasive innovations have transformed *** to colorectal cancer(CRC),there has been a shift towards less invasive surgical techniques and use of endoscopic resection as an alternative for low risk T1 *** role of endoscopic resection is however much more ex.ensive:It is now considered the first line management strategy for most large(≥20 mm)non-pedunculated colorectal polyps,the majority of which are *** is due to the well-established efficacy,safety,and cost-effectiveness of endoscopic techniques compared to *** endoscopic modalities now ex.st with distinct risk-benefit profiles and their outcomes are further improved by site-specific technical modifications,aux.liary techniques,and adverse event miti-gation *** capacity continues to evolve with emerging endoscopic techniques and ex.anding applications,particularly in the confines of a multi-disciplinary setting.

关键词： Cancer Colonoscopy Endoscopy Polyp Endoscopic mucosal resection Endoscopic submucosal dissection

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Population Dynamics and Key Influencing Factors of Microthrix.parvicella Caused Sludge Bulking

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Huanjing Kex.e/Environmental Science 2024年第11期45卷 6766-6774页

作者： Su G.-x. Qi R. x.ao S.-M. Dou D.-C. Guo Y.-x. Gao J. Tianjin Key Laboratory of Aquatic Science and Technology School of Environmental and Municipal Engineering Tianjin Chengjian University Tianjin 300384 China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Given the frequent occurrence of the sludge bulking phenomena caused by Microthrix.parvicella（M. parvicella）overgrowth during the low-temperature period in the full-scale municipal wastewater treatment plant，the filamentous bacteria dynamics of the M. parvicella population were systematically investigated during the completed bulking period using the multi-dimensional integrated filamentous monitoring method combined with the molecular quantitative method. A lab-scale reactor was constructed and successfully simulated bulking phenomena under the low-temperature condition. The trend of dominant filamentous bacterial shift and the main influencing parameters were estimated during the bulking period，to verify the key factors for filament growth and ex.inction of the sludge bulking phenomenon in the full-scale plant. The results showed that the bulking-caused M. parvicella was characterized by significant changes in the diversity of filamentous bacteria，and the dominant filamentous bacterial succession was reflected in the competition between the skeleton filamentous bacteria Type 0092 and Type 0041 and M. parvicella. At lower temperatures，sludge loading was an important controlling factor for the competitive growth advantage of M. parvicella：when the temperature was lower（approx.mately 15°C），low sludge loading［0.05 kg·（kg·d）−1］could lead to the stabilized elevation of M. parvicella，and with the loading increased to 0.1 kg·（kg·d）−1 or more，M. parvicella populations showed a targeted decline despite the presence of the low temperature factor. © 2024 Science Press. All rights reserved.

关键词： filamentous bacteria Microthrix.parvicella population dynamics sludge bulking sludge loading

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轻质铝基熵合金:概述与未来趋势

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Science China Materials 2024年第1期67卷 31-46页

作者：崔立莹张展陈晓光 Department of Applied Science University of Quebec at Chicoutimi555boulevard de l’UniversiteSaguenay G7H 2B1QCCanada

新一代合金——高熵合金的出现,揭示了熵效应在合金设计中的重要意义.受这一概念的启发,轻质铝基熵合金这一概念被提出.随着对低密度结构材料的需求不断增加,这些新型合金在各种应用中具有巨大的潜力.本文综述了轻质铝基熵合金的发展背... 详细信息

新一代合金——高熵合金的出现,揭示了熵效应在合金设计中的重要意义.受这一概念的启发,轻质铝基熵合金这一概念被提出.随着对低密度结构材料的需求不断增加,这些新型合金在各种应用中具有巨大的潜力.本文综述了轻质铝基熵合金的发展背景、设计原理、制造方法、微观结构和力学性能、高温应用,及其发展前景.通过对当前研究的全面调查,本文重点研究分析了122种密度低于4.0 g cm-3的铝基熵合金.轻质铝基熵合金可以弥补传统铝和钛合金在机械性能和密度方面的差距.轻质铝基熵合金优异的热稳定性使其有望成为在高温下使用的结构材料.此外,本文还讨论了轻质铝基熵合金领域的未来发展趋势.机器学习作为有效计算工具,可以极大地提高合金的开发效率.

关键词：高温应用合金设计新型合金机器学习铝基计算工具高熵合金微观结构

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An adaptive machine learning-based optimization method in the aerodynamic analysis of a finite wing under various cruise conditions

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 27-34页

作者： Zilan Zhang Yu Ao Shaofan Li Grace x.Gu Department of Mechanical Engineering University of CaliforniaBerkeley 94720USA Department of Engineering Peking UniversityBeijing 100871China Department of Civil and Environmental Engineering University of CaliforniaBerkeley 94720USA

Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complex.ty of versatile flight *** of ex.sting literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational *** we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise *** methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing *** has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical *** also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements.

关键词： Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network

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Dissipationless layertronics in ax.on insulator MnBi2Te4

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National Science Review 2024年第6期11卷 189-196页

作者： Shuai Li Ming Gong Shuguang Cheng Hua Jiang x.C.x.e School of Physical Science and Technology Soochow University Institute for Advanced Study Soochow University International Center for Quantum Materials School of Physics Peking University Department of Physics Northwest University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University Hefei National Laboratory

Surface electrons in ax.on insulators are endowed with a topological layer degree of freedom followed by ex.tic transport phenomena, e.g., the layer Hall effect. Here, we propose that such a layer degree of freedom can be manipulated in a dissipationless way based on the antiferromagnetic MnBi2Te4with tailored domain structure. This makes MnBi2Te4a versatile platform to ex.loit the ‘layertronics’ to encode, process and store information. Importantly, the layer filter, layer valve and layer reverser devices can be achieved using the layer-locked chiral domain wall modes. The dissipationless nature of the domain wall modes makes the performance of the layertronic devices superior to those in spintronics and valleytronics. Specifically, the layer reverser, a layer version of the Datta–Das transistor, also fills up the blank in designing the valley reverser in valleytronics. Our work sheds light on constructing new generation electronic devices with high performance and low-energy consumption in the framework of layertronics.

关键词： ax.on insulator MnBi2Te4 layertronics antiferromagnetic domain wall dissipationless transport

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In situ TEM investigation of electron irradiation and aging-induced high-density nanoprecipitates in an Mg-10Gd-3Y-1Zn-0.5Zr alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1841-1853页

作者： M.Lv H.L.Ge Q.Q.Jin x.H.Shao Y.T.Zhou B.Zhang x.L.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Materials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China

In-situ electron irradiation and aging are applied to introduce high-density precipitates in an Mg-10Gd-3Y-1Zn-0.5Zr(GWZ1031K,wt.%)alloy to improve the *** results show that the hardness of the Mg alloy after irradiation for 10 h and aging for 9 h at 250℃ is 1.64 GPa,which is approx.mately 64% higher than that of the samples before being *** is mainly attributed to γ'precipitates on the basal plane after irradiation and the high-density nanoscale β'precipitates on the prismatic plane after aging,which should be closely related to the irradiation-induced homogenous *** latter plays a key role in precipitation *** result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

关键词： Mg alloy Electron beam irradiation Hardening Precipitates In-situ TEM

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The preface: Interplay of topological and magnetic orders in the Mn-Bi-Te family

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National Science Review 2024年第2期11卷 6-7页

作者： Fu-Chun Zhang Hai-Zhou Lu x.C.x.e Kavli Institute for Theoretical Sciences University of Chinese Academy of Sciences Department of Physics Southern University of Science and Technology (SUSTech) International Center for Quantum Materials School of Physics Peking University

The discovery and synthesis of MnBi2Te4in 2013 initially garnered little attention [1]. Yet, the revelation of its topological properties in 2019 [2–6] sparked a surge of research into the MnBiTe family. These ex.ensive studies are primarily driven by two objectives:the realization of a high-temperature quantum anomalous Hall effect （QAHE） and the ex.loration of ex.tic phases born from the interplay of topological and magnetic orders,

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