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美国国家级干旱监测业务产品介绍

干旱气象 2006年第1期24卷 90-94页

作者： Mark Svoboda doug lecomte Mike Hayes Richard Heim Karin Gleason Jim Angel Brad Rippey Rich Tinker Mike Palecki David Stooksbury David Miskus Scott Stephens 王涓力（译）不详中国气象局兰州干旱气象研究所甘肃兰州730020

美国需要改进干旱监测与评估方法.干旱是代价昂贵的自然灾害(联邦应急管理局(FEMA),1995; Wilhite,2000),但经常被评估和预报产品的开发者忽略.相比于其他灾害,干旱表现得更模糊并且不适合用传统的评估或预报方法,它相对缓慢的发生以及... 详细信息

美国需要改进干旱监测与评估方法.干旱是代价昂贵的自然灾害(联邦应急管理局(FEMA),1995; Wilhite,2000),但经常被评估和预报产品的开发者忽略.相比于其他灾害,干旱表现得更模糊并且不适合用传统的评估或预报方法,它相对缓慢的发生以及其影响的复杂性,需要有一套新的方法来对它进行评估.干旱监测和预报技术的提高会使我们为应对干旱灾害做更好的准备工作,进行更好的应对实践,从而减少社会对干旱及其影响的脆弱性.

关键词：干旱监测产品介绍美国国家级评估方法业务自然灾害预报产品预报方法干旱灾害

Multi-dimensional morphology of hydride diffusion layer and associated sequential twinning in commercial pure titanium

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Journal of Materials Science & Technology 2022年第8期103卷 105-112页

作者： Qian Wang Shun Xu Yajun Zhao Jean-Sébastien lecomte Christophe Schuman Laboratoire d’Etude des Microstructures et de Mécanique des Matériaux(LEM3) Universitéde Lorraine CNRSArts et Métiers ParisTechMetz57073France Laboratory of Excellence on Design of Alloy Metals for low-mAss Structures(DAMAS) University of Lorraine57073France School of Iron and Steel Soochow UniversitySuzhou 215021China School of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116021China

The dominant hydride precipitates have been well demonstrated to follow two types of orientation relationships(ORs)with Ti matrix:OR1 with{0001}//{001},//and OR2 with{0001}//{111},//.Within the grains with special orientations,the complicated interactions of different hydride variants inside Ti-hydride diffusion layer are characterized in this *** OR1 hydride layer,the orientations of{1010}plane parallel to the sample surface and a-axis parallel to the normal direction prefer multiple OR1 *** orientations favorable for OR2 hydride layer are:{1013}plane parallel to sample surface corresponding to the layer with one OR2 variant dominated and c-axis parallel to the surface normal with multiple OR2 variant layer ***,{1012}extension twins and{1122}contraction twins are activated to accommodate the OR2 hydride-induced surface expansion and local misfit *** stimulation of these two twins is also orientation-dependent:{1012}and{1122}twins are observed in the grains with c-axis parallel to and deviated from the surface normal,*** further variant selection for each twin mode is performed through shear accommodation of hydride-twin pairs.

关键词： Titanium Hydride Cross section Twin Variant selection

Stability of steel thixoforming process

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中国有色金属学会会刊：英文版 2010年第S3期20卷 937-942页

作者： J.C.PIERRET A.RASSILI G.VANEETVELD J.lecomte-BECKERS ThixoUnit ULg Material Sciences UnitDepartment of Aerospace and Mechanical EngineeringUniversity of Liège

To improve the industrialization of the process,the study of a thixoforming line stability was *** thixoforming line is fully automated to optimize the repeatability of the *** of the heating cycle,the slug temperature,the tool temperature and the forming speed were *** each of them,a range of the expected variations in a steady-state process as well as the effects of these variations on the process itself(forming load and parts quality) were *** variations are shown to be *** different tools were used in the *** mathematical simulations were realized on the finite elements code Forge2008with a semi-solid constitutive *** capacity of the model to represent the process stability was *** simulation results are in agreement with the experiment results.

关键词： thixoforming steel high melting point stability robustness process

Conception of tooling adapted to thixoforging of high solid fraction hot-crack-sensitive aluminium alloys

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Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1712-1718页

作者： G.VANEETVELD A.RASSILI J.C.PIERRET J.lecomte-BECKERS Thixo Unit B56University of Liège Special Metallic Materials B52University of Liège

Thixoforging is a type of semi-solid metal processing at high solid fraction (0.7<φs<1), which involves the processing of alloys in the semi-solid *** has to be adapted to this particular process to benefit shear thinning and thixotropic behaviour of such semi-solid *** parameters, such as the forming speed and tool temperature, have to be accurately controlled because of their influence on thermal exchanges between material flow and *** thermal exchanges influence the high-cracking tendency and the rheology of the semi-solid material during forming, which affects parts properties and therefore their *** tests show how thermal exchanges influence quality of thixoforged parts made of 7075 aluminium alloys at high solid fraction by modifying process parameters like forming speed, tool temperature and tool thermal *** an optimum in terms of thermal exchanges has to be found between surface quality and mechanical properties of the part.A direct application is the evaluation of surface quality of thixoforged thin wall parts made of 7075 aluminium alloy.

关键词： thixoforging solid fraction near-net-shaping tooling 7075 aluminium alloys

Studies of two lanthanide coordination polymers built up from dinuclear units

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Journal of Rare Earths 2013年第1期31卷 85-93页

作者： B.Benmerad K.Aliouane N.Rahahlia A.Guehria-Ladoudi S.Dahaoui C.lecomte Laboratory of Crystallography and Thermodynamic Department of Chemistry Faculty of ScienceUniversity A. MIRABejaa CRM2 UMR-CNRS 7036Institut Jean BarriolUniversity Nancy I

The two three-dimensional oxo-bfidged lanthanides {[Ln2（C4H2O4）3（H20）4]· 3H2O}3, with Ln=Ho3＋（1）; Gd3＋（2）, are isomorphous. They have layer-type structures built up from non-centrosymrnetric dinuclear unit Ln2O12（H2O）4, beside three lattice H20 molecules stabilizing the 3D open-frmnework. The building entities are linked through one classical syn-anti g2-carboxylato-K1O：K^1O＇ bridge. Within the bi-polyhedra, two double μ2-O＇; K2O,O＇ bridges and a syn-syn classical one, support the magnetic measurements carried out on holmium compound indicating relatively weak anti-ferromagnetic interactions. The compari- son with magnetic studies on the almost similar reported Gd（III） compound, suggested that concomitant antiferromagnetic and ferro- magnetic properties could not be excluded. The two distinct thermal behaviors evidenced the higher metal-water bond strength with the smaller cation, and revealed the great supramolecular effects generated by hydrogen-bonding patterns.

关键词： lanthanide organic frameworks crystal structure thermal behavior magnetic interactions rare earths

X38CrMoV5 hot-work tool steel as tool material for thixoforging of steel:Numerical and experimental evaluation

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中国有色金属学会会刊：英文版 2010年第S3期20卷 713-718页

作者： A.RASSILI J.C.PIERRET G.VANEETVELD J.H ALLEUX G.WALMAG J.lecomte-BECKERS Thixo Unit ULg Department of Aerospace and Mechanica l EngineeringUniversity of Liège

Although thixoforming of low melting point alloys as aluminum or magnesium is now an industrial reality,thixoforming of high melting point alloys as steel is still at the research *** working temperature,die wearing and production rate are problems that must be solved and are under *** aim of this work is to evaluate the thermal and mechanical loadings applied to the tools during the steel thixoforging process in order to determine whether classical hot-work tool steel can be an appropriate tool *** evaluation has been realized thanks to experimental trials and to simulations on the finite elements code Forge2008.The effect of the loadings on the tool's failure modes are highlighted and compared with the ones observed in classical hot *** this,the failure modes of hot-work tool steel,the X38CrMoV5 or H11,were presented.

关键词： thixoforging steel high melting point tool material

Obesity-induced sperm DNA methylation changes at satellite repeats are reprogrammed in rat offspring

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Asian Journal of Andrology 2016年第6期18卷 930-936页

作者： Neil A Youngson Virginie lecomte Christopher A Maloney Preston Leung Jia Liu Luke B Hesson Fabio Luciani Lutz Krause Margaret J Morris Department of Pharmacology School of Medical Sciences UNSW Australia Sydney NSW 2052 Australia Inflammation and Infection Research School of Medical Sciences UNSW Australia Sydney NSW 2052 Australia Adult Cancer Program Lowy Cancer Research Centre and Prince of Wales Clinical School UNSW Australia Sydney NSW 2052 Australia QIMR Berghofer Medical Research Institute Herston Brisbane Queensland 4006 Australia University of Queensland Diamantina Institute Translational Research Institute University of Queensland 37 Kent Street Woolleongabba Queensland 4102 Australia

There is now strong evidence that the paternal contribution to offspring phenotype at fertilisation is more than just DNA. However, the identity and mechanisms of this nongenetic inheritance are poorly understood. One of the more important questions in this research area is： do changes in sperm DNA methylation have phenotypic consequences for offspring？ We have previously reported that offspring of obese male rats have altered glucose metabolism compared with controls and that this effect was inherited through nongenetic means. Here, we describe investigations into sperm DNA methylation in a new cohort using the same protocol. Male rats on a high-fat diet were 30% heavier than control-fed males at the time of mating （16-19 weeks old, n = 14/14）. A small （0.25%） increase in total 5-methyl-2＇-deoxycytidine was detected in obese rat spermatozoa by liquid chromatography tandem mass spectrometry. Examination of the repetitive fraction of the genome with methyI-CpG binding domain protein-enriched genome sequencing （MBD-Seq） and pyrosequencing revealed that retrotransposon DNA methylation states in spermatozoa were not affected by obesity, but methylation at satellite repeats throughout the genome was increased. However, examination of muscle, liver, and spermatozoa from male 27-week-old offspring from obese and control fathers （both groups from n = 8 fathers） revealed that normal DNA methylation levels were restored during offspring development. Furthermore, no changes were found in three genomic imprints in obese rat spermatozoa. Our findings have implications for transgenerational epigenetic reprogramming. They suggest that postfertilization mechanisms exist for normalising some environmentally-induced DNA methylation changes in sperm cells.

关键词： methylation obesity spermatozoa

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消泡剂对超滤膜的影响

食品与发酵工业 2007年第5期33卷 51-53页

作者： Jean-Paul lecomte 道康宁公司上海200001

膜污垢已成为作为分离和净化系统的超滤膜的主要缺陷。有关膜污垢的原因和理论，以及系统优化、污垢对膜寿命的影响。等研究已广泛开展。特别是人们发现，消泡剂可导致显著的膜污垢。本论文旨在讨论消泡剂膜污垢问题，研究膜污垢产生的... 详细信息

膜污垢已成为作为分离和净化系统的超滤膜的主要缺陷。有关膜污垢的原因和理论，以及系统优化、污垢对膜寿命的影响。等研究已广泛开展。特别是人们发现，消泡剂可导致显著的膜污垢。本论文旨在讨论消泡剂膜污垢问题，研究膜污垢产生的主要原因，并介绍了用于超滤顺流工艺的无污垢消泡剂的开发。

关键词：超滤膜消泡剂净化系统污垢膜寿命原因分离

Livestock induces strong spatial heterogeneity of soil CO2, N2O and CH4 emissions within a semi-arid sylvo-pastoral landscape in West Africa

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Journal of Arid Land 2017年第2期9卷 210-221页

作者： Mohamed H ASSOUMA Dominique SERCA Frederic GUERIN Vincent BLANFORT Philippe lecomte Ibra TOURE Alexandre ICKOWICZ Raphael J MANLAY Martial BERNOU Jonathan VAYSSIERES CIRAD-UMR Selmet Campus International Baillarguet Montpellier 34398 France DP PPZS ISRA-LNERV BP 2057 Dakar Hann Senegal Laboratoire d'Aerologie-OMP Universite Paul Sabatier 14 Avenue Edouard Belin Toulouse 31400 France Geosciences Environnement Toulouse UMR 5563 & UR 234 IRD Universite Paul Sabatier Avenue Edouard Belin 14 Toulouse 31400 France CILSS 03 BP 7049 Ouagadougou Burkina Faso AgroParisTech-UMR Eco&Sols 2 place Viala Montpellier SupAgro Montpellier 34060 France IRD-UMR Eco&Sols 2 place Viala Montpellier SupAgro Montpellier 34060 France

Greenhouse gas （GHG） emissions from the surface soils and surface water receiving animal excreta may be important components of the GHG balance of terrestrial ecosystems, but the associated processes are poorly documented in tropical environments, especially in tropical arid and semi-arid areas. A typical sylvo-pastoral landscape in the semi-arid zone of Senegal, West Africa, was investigated in this study. The study area （706 km2 of managed pastoral land） was a circular zone with a radius of 15 km centered on a borehole used to water livestock. The landscape supports a stocking rate ranging from 0.11 to 0.39 tropical livestock units per hectare depending on the seasonal movements of the livestock. Six landscape units were investigated （land in the vicinity of the borehole, natural ponds, natural rangelands, forest plantations, settlements, and enclosed plots）. Carbon dioxide （CO2）, nitrous oxide （N2O） and methane （CH4） fluxes were measured with static chambers set up at 13 sites covering the six landscape units, and the 13 sites are assumed to be representative of the spatial heterogeneity of the emissions. A total of 216 fluxes were measured during the one-year study period （May 2014 to April 2015）. At the landscape level, soils and surface water emitted an average 19.8 t C-CO2 eq/（hm2.a）（CO2： 82%, N2O： 15%, and CH4： 3%）, but detailed results revealed notable spatial heterogeneity of GHG emissions. CO2 fluxes ranged from 1148.2 （±91.6） mg/（m2.d） in rangelands to 97,980.2 （±4,861.7） mg/（m2.d） in surface water in the vicinity of the borehole. N2O fluxes ranged from 0.6 （±0.1） mg/（m2.d） in forest plantations to 22.6 （±10.8） mg/（m2.d） in the vicinity of the borehole. CH4 fluxes ranged from -3.2 （±0.3） mg/（m2.d） in forest plantations to 8788.5 （±2295.9） mg/（m2.d） from surface water in the vicinity of the borehole. This study identified GHG emission ＂hot spots＂ in the landscape. Emissions from the surface soils were significantly higher in the landscape units most freq

关键词： greenhouse gases soil surface water livestock landscape Senegal