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Developing one-dimensional implosions for inertial confinement fusion science

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High Power Laser Science and engineering 2016年第4期4卷 1-7页

作者： j.L.Kline S.A.Yi A.N.Simakov R.e.Olson D.C.Wilson G.A.Kyrala T.S.Perry S.H.Batha e.L.Dewald j.e.ralph D.j.Strozzi A.G.MacPhee D.A.Callahan D.Hinkel O.A.Hurricane R.j.Leeper A.B.Zylstra R.R.Peterson B.M.Haines L.Yin P.A.Bradley R.C.Shah T.Braun j.Biener B.j.Kozioziemski j.D.Sater M.M.Biener A.V.Hamza A.Nikroo L.F.Berzak Hopkins D.Ho S.LePape N.B.Meezan D.S.Montgomery W.S.Daughton e.C.Merritt T.Cardenas e.S.Dodd Los Alamos National Laboratory Lawrence Livermore National Laboratory

experiments on the National Ignition Facility show that multi-dimensional effects currently dominate the implosion performance. Low mode implosion symmetry and hydrodynamic instabilities seeded by capsule mounting features appear to be two key limiting factors for implosion performance. One reason these factors have a large impact on the performance of inertial confinement fusion implosions is the high convergence required to achieve high fusion *** tackle these problems, a predictable implosion platform is needed meaning experiments must trade-off high gain for performance. LANL has adopted three main approaches to develop a one-dimensional(1D) implosion platform where 1D means measured yield over the 1D clean calculation. A high adiabat, low convergence platform is being developed using beryllium capsules enabling larger case-to-capsule ratios to improve symmetry. The second approach is liquid fuel layers using wetted foam targets. With liquid fuel layers, the implosion convergence can be controlled via the initial vapor pressure set by the target fielding temperature. The last method is double shell targets. For double shells, the smaller inner shell houses the DT fuel and the convergence of this cavity is relatively small compared to hot spot ignition. However,double shell targets have a different set of trade-off versus advantages. Details for each of these approaches are described.

关键词： beryllium capsules double shells inertial confinement fusion liquid layers

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铁电半导瓷的电畴和晶界的成象

压电与声光 1985年第2期 57-60页

作者： j.e.ralph,j.P.Gowers,M.R.Burgess,戴道文英·菲利普研究实验室英·菲利普研究实验室英·菲利普研究实验室

本文描述用扫描电子显微镜的束感应电流模使正温度系数陶瓷铁电畴和晶界成象的实验.讨论了观察到的衬度的形成机理以及这些观察同以前发表的涉及电畴与晶界位垒相互作用的假说的联系.

关键词：电畴衬度晶界晶粒间界晶体点阵成象 eBIC 位垒铁电

Are hydrides under high-pressure-high-temperature superconductors?

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National Science Review 2024年第7期11卷 9-12页

作者： j.e.Hirsch Department of Physics University of California

Contrary to the current consensus, I argue that the existing evidence for high-temperature superconductivity in hydrides under high pressure is not compelling. I suggest that the focus of the field should urgently shift to establish unequivocally experimentally whether or not superconductivity in pressurized hydrides exists, instead of continuing to search for new materials that might show elusive signals of unproven superconductivity at ever higher temperatures. The implications of a negative finding for the theoretical understanding of superconductivity are discussed.

关键词： Hydrides

Annual variation of adult survival of a south-temperate House Wren population in Argentina

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Avian Research 2024年第2期15卷 229-237页

作者： Gustavo j.Fernandez Mariana e.Carro Paulo e.Llambías Grupo de Investigacion en ecofisiología de Fauna Silvestre INIBIOMA-CONICETAsentamiento Universitario San Martín de los Andes(AUSMA)Universidad Nacional Del ComahuePasaje de la Paz 235(8370)San Martín de los AndesNeuquenArgentina Grupo de Investigacion de Biología de Aves IADIZA CCT-MendozaUniversidad Nacional de CuyoAvenida RuizLeal s/n Parque General San Martin5500MendozaArgentina

Identifying factors affecting the survival of individuals is essential for understanding the evolution of life-history traits and population *** numerous studies on this subject in north-temperate environments,there is a lack of equivalent studies at similar latitudes in the ***,we used a 14-year dataset of capture,banding,and resighting to estimate the annual variation in the apparent adult survival probability of a south-temperate population of House Wrens(Troglodytes aedon bonariae).We evaluated temporal variation in sur-vival and the effect of environmental(climatic)and demographic variables(adult abundance,total number of fledglings produced during each breeding season)on survival *** found that the probability of adult survival decreased as the abundance of breeding adults *** density-dependent effect could be related to the resident lifestyle of southern House Wrens,which could determine an intense competition for territories and resources that ultimately would affect their survival.

关键词： Annual variation CjS Density-dependence Survival Troglodytes aedon bonariae

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Using adjacency matrix to explore remarkable associations in big and small mineral data

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Geoscience Frontiers 2024年第5期15卷 61-74页

作者： Xiang Que jingyi Huang jolyon ralph jiyin Zhang Anirudh Prabhu Shaunna Morrison Robert Hazen Xiaogang Ma Department of Computer Science University of IdahoMoscowID 83844USA College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou 350002China earth and Planets Laboratory Carnegie Institution for ScienceWashingtonDC 20015USA Hudson Institute of Mineralogy KeswickVA 22947USA

Data exploration,usually the first step in data analysis,is a useful method to tackle challenges caused by big geoscience *** conducts quick analysis of data,investigates the patterns,and generates/refines research questions to guide advanced statistics and machine learning *** background of this work is the open mineral data provided by several sources,and the focus is different types of associations in mineral properties and *** in mineralogy have been applying different techniques for exploring such *** the explored associations can lead to new scientific insights that contribute to crystallography,mineralogy,and geochemistry,the exploration process is often daunting due to the wide range and complexity of factors *** this study,our purpose is implementing a visualization tool based on the adjacency matrix for a variety of datasets and testing its utility for quick exploration of association patterns in mineral ***,software packages,and use cases have been developed to process a variety of mineral *** results demonstrate the efficiency of adjacency matrix in real-world *** the developed works of this study are open source and open access.

关键词： Adjacency matrix Association analysis Data exploration Mineral informatics Open data

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.D.james j.e.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTeCs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTeC heterogeneity by examining the mechanisms by which mTeCs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Unmixing detrital zircon U-Pb ages reveals tectonic and climatic depositional influences on the Carboniferous Ansilta Formation,Calingasta-Uspallata Basin,Western Argentina

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Geoscience Frontiers 2024年第4期15卷 61-77页

作者： j.R.Malone j.e.Malone j.L.Isbell D.H.Malone j.P.Craddock K.N.Pauls Department of Geological Sciences Jackson School of GeosciencesUniversity of Texas at AustinAustinTX 78712USA Iowa Geological Survey University of IowaIowa CityIA 52240USA Department of Geosciences University of Wisconsin-MilwaukeeMilwaukeeWI 53211USA Department of Geography Geology and the EnvironmentIllinois State UniversityNormalIL 61790-4400USA

The Late Paleozoic Ice Age(LPIA)was a principal control of sedimentation across Gondwana from the late Devonian through early *** assess the hypothesis that glacial to interglacial transitions in western Argentina were the primary control influencing sediment routing patterns among the various Carboniferous-Permian basins in western *** Carboniferous Ansilta Formation consists of glaciomarine,nearshore,and fluvial systems deposited during the LPIA along the eastern margin of the Calingasta-Uspallata Basin in *** lower,glacially influenced succession of the Ansilta Formation records at least five glacial advances;the upper succession of consists of progradational shallow marine,deltaic,and fluvial *** combine 1225 new U-Pb zircon ages from six samples of the Carboniferous Ansilta Formation in the Calingasta-Uspallata Basin with 5864 U-Pb ages from 147 pub-lished samples in the detrital Pymix forward mixture model to characterize provenance *** the glacially influenced lower Ansilta Formation,sediment was derived locally from the Protoprecordillera,which was a prominent highland with alpine glaciers flowing west and east into the Calingasta-Uspallata and Paganzo basins,***,there was little or no connection between these two basins during Serpukhovian-Bashkirian *** fluvial/deltaic upper Ansilta had distal sediment sources in the Sierras ***,our results support the collapse of the Protoprecordillera topographic barrier,enabling drainage patterns connecting the Paganzo and Calingasta-Uspallata basins by late Pennsylvanian-early Permian time.

关键词： Late Paleozoic Ice Age Argentina Calingasta-Uspallata Basin Ansilta Formation Detrital zircon provenance

行星科学研究中热发射光谱的实验测量与定标方法

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空间科学学报 2024年第2期44卷 270-286页

作者：杨亚洲 MILLIKeN ralph e BRAMBLe Michael S PATTeRSON William R 邹永廖刘洋中国科学院国家空间科学中心空间天气学国家重点实验室北京100190 布朗大学地球环境与行星科学学院普罗维登斯02912

准确的物质组成信息是解译行星体形成与演化历史的关键,可见–近红外遥感光谱探测一直是获取行星表面成分的主要技术手段.在热红外谱段光谱特征更为丰富,因此随着探测技术的发展,其在行星探测中得到越来越多的应用.尤其是在目前已经实... 详细信息

准确的物质组成信息是解译行星体形成与演化历史的关键,可见–近红外遥感光谱探测一直是获取行星表面成分的主要技术手段.在热红外谱段光谱特征更为丰富,因此随着探测技术的发展,其在行星探测中得到越来越多的应用.尤其是在目前已经实施与立项的国内外小行星探测任务中,都将热发射光谱仪作为核心载荷之一.为了更好地对将来获取的热发射光谱数据进行解译,建立科学合理的数据处理与定标方案是必不可少的.本文对用于行星科学研究的热发射光谱测量装置的设计、测量及数据处理方法进行了系统分析.针对低温、真空条件下热发射测量过程中样品辐射信号与仪器辐射信号难以分离的问题,提出并论证了基于傅里叶变换红外光谱仪原始测量信号–干涉图的数据处理方法.该方法可以更为有效地分离出样品实际辐射信号,从而获得更为准确的发射率光谱数据.研究结果可为国内相关热发射测量装置的设计与搭建以及未来天问二号等探测数据的处理与科学解译提供参考.

关键词：行星探测热发射光谱实验室测量定标

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Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of Optoelectronics 2024年第2期17卷 87-97页

作者： O.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi e.Diez j.e.Velázquez-Pérez Y.M.Meziani j.M.Caridad j.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de excelencia en Luz y Materia estructurada(LUMeS) University of Salamanca37008 SalamancaSpain Research Center for electronic and Optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFeTs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFeT *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasmonic