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中国计量 2004年第9期 9-10页

作者：杨学金马丁.博赛 j.f.马加纳沈伟民张恒烈湖南省质量技术监督局英国国家度量衡实验室国际法制计量局上海市质量技术监督局江苏省质量技术监督局

地球演化历史中氧逸度变化对壳幔循环启动、风化和超大陆循环的指示

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Science Bulletin 2024年第1期69卷 97-102页

作者：王瑞邬绍宸 Roberto f.Weinberg William j.Collins Peter A.Cawood State Key Laboratory of Geological Processes and Mineral Resources Institute of Earth SciencesChina University of GeosciencesBeijing 100083China frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China School of Earth Atmosphere and EnvironmentMonash UniversityClayton VIC 3800Australia The Institute for Geoscience Research Curtin UniversityPerth WA 6102Australia

We apply a zircon redox index to a global compilation of detrital zircons to track the variation of oxidation state,expressed asΔfMQ,through Earth's history.Those from I-type rocks,which comprise mantle and crustal igneous protoliths,including tonalite–trondhjemite–granodiorites(TTGs),generally have a high oxidation state(ΔfMQ>0).In contrast,zircons from igneous rocks derived from supracrustal source rocks(S-type)are commonly reduced(ΔfMQfunction derived from the Gaussian-Kernel-Density-Estimation,we use the maximum likelihood estimation(MLE)to distinguish Stype from I-type zircons through Earth's history using zircon redox.Voluminous S-type magma production shows a ca.600 Ma cyclicity that is closely related to the supercontinent cycle.We link a cyclic drop in redox values after 2.6 Ga to periodic S-type magma generation associated with burial and melting of metasedimentary rocks during supercontinent assembly and amalgamation.TheΔfMQ of the detrital zircons rise at~3.5 Ga followed by a consistent averageΔfMQ>0 over the last 3 Ga.Given that the redox state of magmas is independent of crustal thickness and silica variation,and elevated values are likely more closely related to tectonic setting,we suggest that the consistent averageΔfMQ>0 from ca.3.5 Ga onwards relates to recycling of oceanic lithosphere back into the mantle in what eventually became established as subduction zones.The more reduced magmas associated with sedimentary sources,became established at 2.6 Ga,presumably in response to continental rocks rising above sealevel,and follow peaks of productivity associated with the supercontinent cycle.

关键词： Oxidation state Supercontinent Weathering Subduction Zircon Granite

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全球蜂群数量和蜂蜜产量呈上升趋势

中国蜂业 2024年第4期75卷 52-53,57页

作者：罗照明(编译) 孟丽峰(编译) Phiri Bernard j.f.vre Damien Hidano Arata 中国蜂产品协会北京100050 中国农业科学院蜜蜂研究所北京100093 不详

蜜蜂在社会经济上具有重要意义,因为它们在农作物授粉中发挥着关键作用,并生产对社会和许多行业至关重要的各种蜂产品,它们对生态和社会的可持续发展具有重要贡献。具有社会经济价值的蜂产品包括蜂蜜、蜂蜡、蜂胶、花粉、蜂王浆等,被广... 详细信息

蜜蜂在社会经济上具有重要意义,因为它们在农作物授粉中发挥着关键作用,并生产对社会和许多行业至关重要的各种蜂产品,它们对生态和社会的可持续发展具有重要贡献。具有社会经济价值的蜂产品包括蜂蜜、蜂蜡、蜂胶、花粉、蜂王浆等,被广泛应用于食品、化妆品、药品,甚至用于工业中。因此,全球蜂群数量即将或持续下降可能会产生广泛的社会经济影响。Bernard j.Phiri等基于联合国粮农组织(fAO)60年来收集的数据,包括蜂群数量、蜂蜜产量、蜂蜡产量,分析并评估了全球60年蜂业变化。

关键词：蜂蜜产量社会经济价值蜂产品蜂群数量蜂业社会经济影响蜂王浆蜂蜡

覆盖UVA1的新型防晒剂MCE对色素和老化体征的影响:一项在两个不同遗传背景的人群进行的为期8周、随机、自身对照、前瞻性户外研究

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中华皮肤科杂志 2024年第6期57卷 579-580页

作者： f. flament D. G. Mercurio B. Muller j. Li C. Tricaud f. Bernerd A. Roudot D. Candau T. Passeron L'Oréal Research and Innovation Clichy France L'Oréal Research and Innovation Rio de Janeiro Brazil L'Oréal Research and Innovation Shanghai China L'Oréal Research and Innovation Aulnay-sous-Bois France L'Oréal Research and Innovation Chevilly-Larue France CHU Nice Department of Dermatology Université Côte d'Azur Nice France Université Côte d'Azur INSERM U1065 C3M Nice France

一、引言在不同的紫外线(UV)波段中,长波UVA(UVA1,340~400nm)具有更高的皮肤穿透力,并且受气象条件和臭氧层厚度等环境参数的影响较小,因此更容易到达皮肤深部的真皮层,对细胞成分(如DNA、脂质和蛋白质)造成氧化损伤。UVA1已经越来越多... 详细信息

一、引言在不同的紫外线(UV)波段中,长波UVA(UVA1,340~400nm)具有更高的皮肤穿透力,并且受气象条件和臭氧层厚度等环境参数的影响较小,因此更容易到达皮肤深部的真皮层,对细胞成分(如DNA、脂质和蛋白质)造成氧化损伤。UVA1已经越来越多地被发现与衰老、致癌作用、多种皮肤疾病和色素问题相关。

关键词： UVA1 真皮层自身对照致癌作用皮肤疾病防晒剂遗传背景氧化损伤

国际法制计量局局长j.f.Magana先生祝贺我国举办“世界计量日”活动

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中国计量 2003年第6期 13-14页

作者：马加纳国际法制计量局局长BIML Director

Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix composites by crystal plasticity finite element method

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journal of Materials Science & Technology 2024年第2期169卷 53-67页

作者： Y.B.Zhang S.j.Song f.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension crystal plasticity finite element(3D CPfE)simulations,co-deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix composites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive deformations.Accordingly,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered composites(MNCs).By detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always accompanied by high-stress concentration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase interface.It then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic correlation.Then by inserting a high density of high-energy interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and ductility.Such hetero-phase interface chosen by a couple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based constitutive modeling Hetero-phase interface Crystal plasticity finite element

亚热带森林植物的叶片和根系功能性状部分耦合但具有不同的群落性状分布格局

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journal of Plant Ecology 2024年第1期17卷 94-110页

作者： Wenqi Luo Oscar j Valverde-Barrantes Monique Weemstra james f Cahill jr Zi Wang Dong He Yongfa Chen Chengjin Chu Youshi Wang State Key Laboratory of Biocontrol School of Life Sciences/School of EcologySun Yat-sen UniversityGuangzhou 510275China International Center for Tropical Botany Department of Biological SciencesFlorida International UniversityMiamiFL 33199USA Department of Biological Sciences University of AlbertaEdmontonABT6G 2E9Canada School of Ecology and the Environment Xinjiang UniversityUrumqi 830046China

植物的生态过程依赖于叶片和根系的功能运行,但少有研究同时关注这两类性状在群落中的分布格局(CTD)。本文测定了广东亚热带森林44种共生木本植物的16个叶片和根系性状,旨在检验类比的叶片和根系性状是否耦合,是否沿类似的功能性状谱变... 详细信息

植物的生态过程依赖于叶片和根系的功能运行,但少有研究同时关注这两类性状在群落中的分布格局(CTD)。本文测定了广东亚热带森林44种共生木本植物的16个叶片和根系性状,旨在检验类比的叶片和根系性状是否耦合,是否沿类似的功能性状谱变异,是否表现出类似的CTD,其CTD和群落加权平均性状值(CWM)是否沿环境梯度表现出类似的响应。研究结果表明,叶片和根系性状变异的第一轴均呈显出由资源获取向资源保守变异的经济学谱,但叶片变异的第二轴主要由叶片碳含量表征,而根系变异的第二轴主要由反映菌根协作程度的根系粗细表征。类比的叶片和根系化学性状整体正相关,但形态性状的耦合程度较低。在群落水平上,叶片和根系性状第一轴的CWM均随海拔升高而变得更保守,而第二轴的变化则不一致。随土壤磷含量的降低或钾含量的升高,根系变得更细和在养分性状上更保守,而叶片性状无显著变化。当整合多维性状轴时,叶片性状呈发散格局,且随海拔、土壤磷和钾含量的增加呈收敛趋势;而根系性状呈收敛格局,但沿上述环境梯度呈发散趋势。该研究强调,叶片和根系性状与环境互作的差异可能导致不同的性状分布格局;植物可通过多样的地上和地下功能设计应对环境异质性。

关键词：性状维度群落构建叶片性状根系性状植物经济谱群落性状结构亚热带森林

Requirement Modeling and Verification for Automatic flight System Modes Based on MTRDL

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Ruan jian Xue Bao/journal of Software 2024年第9期35卷

作者： Xu H. Huang Z.-Q. Hu j. Tao C.-Q. Wang j.-Y. Shi f. College of Computer Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China School of Information Engineering Xuzhou University of Technology Xuzhou 221018 China

During the automatic flight of civil aircraft, the transition of automatic flight system modes is an important factor affecting safety. With the rapid growth of functions and complexity of modern civil aircraft airborne systems, the safety analysis and verification of automatic flight system mode transition in the requirement phase has become an important challenge. The complexity of flight mode transition is not only reflected in the interaction among multiple flight modes necessary during the automatic flight but also in the complex data and control cross-linking relationships between the mode transition process and the external environment. Additionally, these cross-linking relationships imply the safety properties of the flight mode transition process, which increases the application difficulty of formal methods. This study proposes a domain specific modeling and verification framework. first, a modeling language MTRDL for transition requirements of automatic flight system modes and a modeling method based on extended SysML language are put forward. Secondly, the safety property-assisted protocol method based on safety requirement templates is proposed. finally, the effectiveness of the method in the requirement verification of automatic flight system mode transition is proven by a case study of a certain aircraft’s itemized requirements. © 2024 Chinese Academy of Sciences. All rights reserved.

关键词： automatic flight sytem mode formal methods safety property SysML modelling

Thermoluminescence characterization of natural and synthetic irradiated Ce-monazites

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journal of Rare Earths 2024年第4期42卷 643-650页

作者： V.Correcher C.Boronat j.Garcia-Guinea j.f.Benavente T.Rivera-Montalvo CIEMAT Av.Complutense 4028040MadridSpain MNCN-CSIC J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of synthetic and natural Ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical process.The kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic CePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence mechanism.Each peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,Ce3+?Ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,frenkel defects,ODCs or NBOHCs).

关键词： Thermoluminescence Kineticparameters Phosphate Ce-monazite Defects Rare earths

三轴形变核^(131)Ba中的奇异集体激发模式

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物理学报 2024年第11期73卷 89-100页

作者：韦锐周厚兵王思成丁兵强赟华贾晨旭陈红星郭松 C.M.Petrache D.Mengoni A.Astier E.Dupont 吕冰锋 D.Bazzacco A.Boso A.Goasduff f.Recchia D.Testov f.Galtarossa G.jaworski D.R.Napoli S.Riccetto M.Siciliano j.j.Valiente-Dobon C.Andreoiu f.H.Garcia K.Ortner K.Whitmore A.Ataç-Nyberg T.Bäck B.Cederwall E.A.Lawrie I.Kuti D.Sohler T.Marchlewski j.Srebrny A.Tucholski 广西师范大学物理科学与技术学院桂林541004 广西核物理与核技术重点实验室桂林541004 中国科学院近代物理研究所兰州730000 中国科学院大学北京100049 巴黎萨克雷大学 CNRS/IN2P3IJCLab奥赛91405 帕多瓦大学物理和天文学系帕多瓦I-35131 意大利国家核物理研究所帕多瓦分部帕多瓦I-35131 意大利国家核物理研究所莱尼亚罗国家实验室莱尼亚罗(帕多瓦)I-35020 费拉拉大学理学与自然科学院费拉拉西蒙菲莎大学化学系本拿比BC V5A 1S6 皇家理工学院物理系斯德哥摩尔S-10691 国家研究基金会iThemba加速器科学实验室西萨默塞特7123 西开普大学物理与天文系贝尔维尔ZA-7535 HUN-REN原子核研究所德布勒森4001 华沙巴斯德拉大学重离子实验室华沙02-093

利用意大利Legnaro实验室串列静电加速器提供的65 MeV^(13)C束流与122Sn靶的熔合蒸发反应布居了^(131)Ba的高自旋态,并搭建了新的能级纲图.新的能级纲图由15条转动带组成,包括三对手征双重带,其中两对正宇称手征带为赝自旋-手征四重带.... 详细信息

利用意大利Legnaro实验室串列静电加速器提供的65 MeV^(13)C束流与122Sn靶的熔合蒸发反应布居了^(131)Ba的高自旋态,并搭建了新的能级纲图.新的能级纲图由15条转动带组成,包括三对手征双重带,其中两对正宇称手征带为赝自旋-手征四重带.正负宇称手征带通过一系列增强的E1跃迁连接,表明它们之间存在八极关联.在低自旋区域搭建了一条新的转动带,通过一系列γ跃迁向νh1_(1/2)晕带退激.这种能级结构与摇摆带相似,但基于现有的实验证据还难以将它确认为摇摆带,不能排除其他集体激发机制,如γ振动的影响.

关键词：高自旋态手征带赝自旋八极关联摇摆运动