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Anisotropic thermal expansion in high-entropy multicomponent AlB_(2)-type diboride solid solutions

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International Journal of Extreme Manufacturing 2023年第1期5卷 331-343页

作者： Frédéric Monteverde Mattia Gaboardi Federico Saraga Lun Feng William Fahrenholtz Gregory Hilmas National Research council of Italy Institute of Science Technology and Sustainability for CeramicsFaenza 48018RAItaly Elettra—Sincrotrone Trieste S.c.P.A Strada Statale 14—Km 1635 in AREA Science ParkBasovizza 34149TriesteItaly Missouri University of Science and Technology RollaMO 65409United States of America AUREL Spa I-47015(ModiglianaItaly) BLUE ORIGIN 98302(KentWashington US).

High-entropy(HE)ultra-high temperature ceramics have the chance to pave the way for future applications propelling technology advantages in the fields of energy conversion and extreme environmental *** others,HE diborides stand out owing to their intrinsic anisotropic layered structure and ability to withstand ultra-high ***,we employed in-situ high-resolution synchrotron diffraction over a plethora of multicomponent compositions,with four to seven transition metals,with the intent of understanding the thermal lattice expansion following different composition or synthesis *** a result,we were able to control the average thermal expansion(TE)from 1.3×10^(−6)to 6.9×10^(−6)K^(−1)depending on the combination of metals,with a variation of in-plane to out-of-plane TE ratio ranging from 1.5 to 2.8.

关键词： ultra-high temperature ceramics borides high-entropy ceramics spark plasma sintering synchrotron diffraction anisotropic thermal expansion

ENABLING cROP DIVERSIFIcATION TO SUPPORT TRANSITIONS TOWard MORE SUSTAINABLE EUROPEAN AGRIFOOD SYSTEMS

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Frontiers of Agricultural Science and Engineering 2021年第3期8卷 474-480页

作者： Antoine MESSEAN Loïc VIGUIER Lise PARESYS Jean-Noel AUBERTOT Stefano cANALI Pietro IANNETTA Eric JUSTES Alison KARLEY Beatrix KEILLOR Laura KEMPER Frédéric MUEL Barbara PANcINO Didier STILMANT christine WATSON Helga WILLER Raul ZORNOZA French National Institute for Agriculture Food and Environment(INRAE)Eco-InnovF-78850 Thiverval-GrignonFrance French National Institute for Agriculture Food and Environment(INRAE)UMR AGIRToulouseFrance council for Agricultural Research and Economics-Research centre for Agriculture and Environment(cREA-AA) 00184 RomeItaly The James Hutton Institute InvergowrieDundeeDD25DAUK French Agricultural Research centre for International Development(cIRAD) Persyst DepartmentF-34398 MontpellierFrance Research Institute of Organic Agriculture(FiBL) 5070 FrickSwitzerland Terres Inovia F-78850 Thiverval-GrignonFrance University of Tuscia Department of EconomicsEngineeringSociety and Business Organization01100 ViterboItaly Wallon Agricultural Research centre(cRA-W) Sustainabilitysystems and prospectives DepartmentB-6800 LibramontBelgium Scotland’s Rural college(SRUc) Craibstone EstateAberdeen AB219YAUK Technical University of cartagena Department of Agricultural EngineeringCartagenaSpain

European cropping systems are often characterized by short rotations or even monocropping,leading to environmental issues such as soil degradation,water eutrophication,and air pollution including greenhouse gas emissions,that contribute to climate change and biodiversity *** use of diversification practices(i.e.,intercropping,multiple cropping including cover cropping and rotation extension),may help enhance agrobiodiversity and deliver ecosystem services while developing new value *** its benefits,crop diversification is hindered by various technical,organizational,and institutional barriers along value chains(input industries,farms,trading and processing industries,retailers,and consumers)and within sociotechnical systems(policy,research,education,regulation and advisory).Six EU-funded research projects have joined forces to boost crop diversification by creating the European crop Diversification cluster(cDc).This cluster aggregates research,innovation,commercial and citizen-focused partnerships to identify and remove barriers across the agrifood system and thus enables the uptake of diversification measures by all European value-chain *** cDc will produce a typology of barriers,develop tools to accompany actors in their transition,harmonize the use of multicriteria assessment indicators,prepare policy recommendations and pave the way for a long-term network on crop diversification.

关键词： crop rotation lock-in intercropping multiple cropping networking

Analysis of mechanical behavior and in situ observations of cu-Al-Be SMA under biaxial compressive tests by using DIc

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Analysis of mechanical behavior and in situ observations of ...

Synthesis, crystal Structure and Infrared characterization of Bis(4-dimethylamino-pyridinium) Tetrachlorocuprate

实验力学国际会议

作者： Sylvain calloch christophe Bouvet Francois Hild céric Doudard christian Lexcellent LMT-cachan LMAR.chaléat

＜正＞ A Digital Image correlation technique is used to develop and validate a new biaxial compression set-up. Some experimental tests have been performed under proportional and nonproportional loading conditions with the experimental set-up. During these tests, a particular attention is paid to the appearance and the disappearance of martensite plates during the loading path. By using a long distance microscope with a ccD camera, we show the importance of the mechanical loading path shape on the martensite formation.

关键词： Mechanical testing shape memory alloy digital image correlation technique in situ observations

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American Journal of Analytical chemistry 2015年第5期6卷 446-456页

作者： Mahjouba Ben Nasr Frédéric Lefebvre chérif Ben Nasr Laboratoire de chimie des Matériaux Faculté des Sciences de Bizerte Université de Carthage Zarzouna Tunisie Laboratoire de chimie Organométallique de Surface (LcOMS) Ecole Supérieure de Chimie Physique Electronique Villeurbanne France

The chemical preparation, crystal structure and spectroscopic characterization of a novel organic-inorganic hybrid material, bis(4-dimethylaminopyridinium) tetrachlorocuprate, have been reported. This compound crystallizes in the monoclinic system in space group c2/c and cell parameters a = 12.4356 (18), b = 12.0901 (17), c = 14.094 (2) Å, β = 115.303 (2)°, Z = 4 and V = 1915.8 (5) Å3. In the title salt, (c7H11N2)2cucl4, both 4-dimethylaminopyridinium cations are protonated at their pyridine N atoms. The geometry of the cucl2-4 ions is intermediate between tetrahedral and square planar. The atomic arrangement can be described by an alternation of inorganic layers built up by tetrachlorocuprate anions and organic layers formed by 4-dimethylaminopyridinium cations. The organic layers are located in sandwich between the inorganic layers. The anionic and cationic layers are held together by N-H···cl and c-H···cl hydrogen bonds into a three-dimensional network. The individual cations are π-π stacked with their neighbors at a distance of 3.7622 (5) Å. The vibrational absorption bands were identified by infrared spectroscopy and DFT calculations allowed their attribution.

关键词： crystal Structure 4-Dimethylaminopyridine Hydrogen Bonds π-π Interactions DFT calculations

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能源领域文献计量学分析

科学观察 2010年第2期5卷 1-9页

作者： éric Archambault Grégoire cté 朱海峰 Science-Metrix 1335A avenue du Mont-Royal EstMontréalQuébec H2J1Y6(Canada)

在全球经济日新月异的今天,能源问题逐渐成为世界各国政要需要解决的头等大事,自然,如何界定、衡量、评估能源的研究与发展也已成为各国智囊的首要任务。该文独创了多管齐下的方法清晰地描述了能源领域的研究现状:从能源研究机构发表的... 详细信息

在全球经济日新月异的今天,能源问题逐渐成为世界各国政要需要解决的头等大事,自然,如何界定、衡量、评估能源的研究与发展也已成为各国智囊的首要任务。该文独创了多管齐下的方法清晰地描述了能源领域的研究现状:从能源研究机构发表的论文中筛选出与能源研究紧密相关的关键词组执行检索命令,生成最基本的能源论文数据组,然后通过能源专业期刊以及参考文献和引文对能源论文数据组进行扩展。该方法巧妙地同时保持了较高的查全率与查准率。数据分析结果表明,自1996年以来能源领域的论文翻了一番,其中中国保持了惊人的增长速度,论文数量有了大幅攀升,且科学研究专业化程度明显提高。与此相比,许多英语国家(除加拿大的能源领域研究好于世界平均水平)的能源研究进展缓慢,逐渐失去了传统的领先优势。

关键词：能源文献计量国际对比研究机构加拿大能源技术中心

Structure, Tree Growth and Dynamics of <I>cedrus atlantica</I>Manetti Forests in Theniet El Had National Park (N-W Algeria)

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Open Journal of Ecology 2018年第8期8卷 432-446页

作者： Mohamed Sarmoum Rafael Ma Navarro-cerrillo Frédéric Guibal Fatiha Abdoun Laboratory of Plant Physiology and Soil culture Faculty of Nature and Life Sciences Ibn Khaldoun University Tiaret Algeria Department of Forestry Engineering University of Cordoba Cordoba Spain Mediterranean Institute of Biodiversity and Marine and continental Ecology (IMBE) Aix-Marseille University (AMU) Aix-en-Provence France Laboratory of Plant Ecology and Environment Faculty of Biological Sciences University of Science and Technology Houari Boumediene (USTHB) Alger Algeria

In North Africa, cedrus atlantica forests are in decline, following decades of anthropogenic pressure and repeated drought events. Mixed c. atlantica-Quercus ilex stands located in the Theniet El Had National Park (northwestern Algeria) were considered in the present study. Based on a stratified sampling, six temporary plots were established to describe structure (species composition, density, total height, diameter and basal area) and radial growth in relation to type of stand (pure and mixed), using a dendroecological approach. The diameter distribution of c. atlantica indicated the presence of few young individuals and a poor regeneration status in all the stands. The density and basal area of c. atlantica were significantly higher in pure stands, which necessitate silvicultural operations. In contrast, Q. ilex showed a progressive dynamic, at moderate altitude. Radial growth showed a significant decline from 1980 to the 2000s. The absence of an appropriate management plan and the increase in anthropogenic effects, without ruling out a role for the current climate conditions marked by drought, seem to be the causes of c. atlantica decline.

关键词： Atlas cedar Algeria Structure Regeneration Radial Growth Forest Management

三洋Xacti VPc c1多功能数码相机

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科学时代 2004年第1期 14-16页

作者： ric

日本三洋(Sanyo)公司推出了其旗舰级 DV-Sanyo Xacti VPc cl,为历来最轻巧的320万像素高品质数码摄像机。该机采用按人体工学设计的圆滑机身,不但突破了传统四方的造型还可以单手操作,不需切换镜头,即可以同时进行录影和拍照。Xacti VPc... 详细信息

日本三洋(Sanyo)公司推出了其旗舰级 DV-Sanyo Xacti VPc cl,为历来最轻巧的320万像素高品质数码摄像机。该机采用按人体工学设计的圆滑机身,不但突破了传统四方的造型还可以单手操作,不需切换镜头,即可以同时进行录影和拍照。Xacti VPc cl 还拥有强大的 MPEG 4格式(640×480)影像功能,具备 cD 品质的影音效果,随时随地拥有视觉与感官的顶级快拍享受。最轻巧 DV—最具行动性的口袋型 DV

关键词：数码相机 VPc Xacti VPc c1 功能

Induced structural modifications in ZnS nanowires via physical state of catalyst:Highlights of 15R crystal phase

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Nano Research 2022年第1期15卷 377-385页

作者： Sumit Kumar Frederic Fossard Gaelle Amiri Jean-Michel chauveau Vincent Sallet Groupe d'Etude de la Matiere condensee(GEMAc) Universite Paris-SaclayCNRS-Universite de Versailles St Quentin en Yvelines45 avenue des Etats-UnisVersailles 78035France Laboratoire d'Etude des Microstructures(LEM) CNRS-ONERAUniversite Paris-Saclay29 avenue Division LeclercChatillon 92322France

Peculiar and unique growth mechanisms involved in semiconductor nanowires(NWs)pave the way to the achievement of new crystallographic phases and remarkable material properties,and hence,studying polytypism in semiconductor NWs arouses a strong interest for the next generation of electronic and photonic *** this context,the growth of ZnS nanowires has been investigated,as bulk ZnS compound exhibits numerous unstable polytypes at high temperatures,but their stable occurrence is highly anticipated in a nanowire due to its special quasi-dimensional shape and growth *** this work,the idea is to provide a change in the growth mechanism via the physical state of catalyst droplet(liquid or solid)and hence,study the induced structural modifications in ZnS *** HRTEM images of VLS(via liquid alloyed catalyst)grown ZnS NWs show periodic stacking faults,which is precisely identified as a stacking sequence of cubic or hexagonal individual planes leading to an astonishing 15R crystal *** crystallographic phase is observed for the first time in ***,NWs grown with VSS(via solid catalyst)show crystal polytypes of zinc blende and *** calculate and discuss the role of cohesive energies in the formation of such ZnS ***,we present the selection rules for the crystallization of such 15R structure in NWs and discuss the involved VLS and VSS growth mechanisms leading to the formation of different crystal phases.

关键词： ll-VI semiconductors MOcVD vapor-liquid-solid(VLS) vapor-solid-solid(VSS) TEM analysis polytypism

Dynamic performance and reflection sensitivity of quantum dot distributed feedback lasers with large optical mismatch

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Photonics Research 2021年第8期9卷 1550-1558页

作者： BOZHANG DONG JIANAN DUAN HEMING HUANG JUSTIN cNORMAN KENIcHI NISHI KEIZO TAKEMASA MITSURU SUGAWARA JOHN EBOWERS FRéDéric GRILLOT LTcI Telecom ParisInstitut Polytechnique de Paris19 Place Marguerite Perey91120 PalaiseauFrance Institute for Energy Efficiency University of CaliforniaSanta BarbaraCalifornia 93106USA Materials Department University of CaliforniaSanta BarbaraCalifornia 93106USA QD Laser Inc.KawasakiKanagawa 210-0855Japan Department of Electrical and computer Engineering University of CaliforniaSanta BarbaraCalifornia 93106USA center for High Technology Materials University of New-MexicoAlbuquerqueNew Mexico 87106USA current address:State Key Laboratory on Tunable Laser Technology School of Electronic and Information EngineeringHarbin Institute of TechnologyShenzhen 518055China

This work reports on a high-efficiency In As/Ga As distributed feedback quantum dot *** large optical wavelength detuning at room temperature between the lasing peak and the gain peak causes the static,dynamic,and nonlinear intrinsic properties to all improve with temperature,including the lasing efficiency,the modulation dynamics,the linewidth enhancement factor,and consequently the reflection *** reported show an optimum operating temperature at 75°c,highlighting the potential of the large optical mismatch assisted single-frequency laser for the development of uncooled and isolator-free high-speed photonic integrated circuits.

关键词： mismatch optical tuning