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Non-equilibrium Statistic Features in Dissipative Heavy Ion Collision ^(27)Al+ ^(27)Al

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Chinese Physics Letters 1999年第12期16卷 876-878页

作者： WANG Qi LI Song-lin TIAN Wen-dong HU Peng-yun LU Jun F.Amorini m.Cabibb G.Cardellas P.Figuere A.musumarra m.Papa G.pappalardo F.Rizzo S.Romano S.Tudisco B.Heusch Institute of modern Physics Chinese Academy of SciencesLanzhou 730000 Istituto Nazionale di Fisica Nucleare the Laboratorio Nazionale del SudItaly Istituto Nazionale di Fisica Nuclearr SezCataniaItaly Dipartimento di Fisica University Catania Italy Centre de Recherches Nucleaires StrasbourgFrance

The excitation functions of dissipative products have been measured in the reaction 27Al+27Al at incident energies from 114 to 127meV in steps of 200keV. Detection angles vary continuously from 10.4° to 57.4° in laboratory system. An angular coherent width more than 40° in center of mass is obtained. The results from the analysis of excitation functions with nonself-averaging are characterized by a quasi-periodic long-range energy structure embedded in the disorder Ericson fluctuation.

关键词： excitation equilibrium steps

Friction coefficient and microhardness of anodized aluminum alloys under different elaboration conditions

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Transactions of Nonferrous metals Society of China 2015年第6期25卷 1950-1960页

作者： m.GUEZmIL W.BENSALAH A.KHALLADI K.ELLEUCH m.DEPETRIS-WERY H.F.AYEDI Laboratoire de Génie des matériaux et Environnement (LGmE) IUT mesures Physiques d’Orsay-University of Paris-sud 11

The effects of anodizing conditions （electrolyte, current density and temperature） on the friction coefficient and Vickers mierohardness of anodic oxide layers formed on A1 5754 and A1 1050A substrates were investigated. The studied properties were examined using DELTALAB HVS-1000 Vickers mierohardness tester and rotating pin on disc tribometer. It was established that the highest microhardness （〉HV 400） and the lowest friction coefficient （〈0.4） were obtained with the oxalic acid addition of 10 g/L at high current density of 3 A/dm2 and low temperature of 5 ~C. The presence of oxidized mg through the anodic oxide layer formed on A1 5754 was examined using glow-discharge optical emission spectroscopy （GDOES）. The mgO was found to act negatively on the mechanical property of the layer. Finally, the scanning electron microscopy （SEm）, energy dispersive X-ray spectroscopy （EDS）, and atomic force microscopy （AFm） were used to characterize the anodic layer before and after friction tests. It is found that the wear mechanism is related to many aspects of the initial morphology, chemical composition of the layer （C, S and mg）, porosity and internal stress.

关键词： aluminium alloy anodization friction coefficient microhardness dry sliding friction surface characterization

microbial Activity Indices: Sensitive Soil Quality Indicators for Trace metal Stress

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Pedosphere 2005年第4期15卷 409-416页

作者： LI Yong-Tao T. BECQUER2 C. QUANTIN m. BENEDETTI P. LAVELLE DAI Jun College of Natural Resources and Environment South China Agricutrual University Guangzhou 510642 （China） UmR 137 Biodiversité et Fonctionnement des Sols Institut de Recherche Pour le Déueloppement （France） Université Paris sud XI FRE Orsay Terre 2566 Bat 504 91405 Cedex （France） UmR-CNRS 7047 Lab. de Géochimie et Métallogénie/Université Pierre et Marie Curie （France）

Physicochemical properties, total and DTPA （diethylenetriaminepentaacetic acid）-extractable Cu, Zn, Pb and Cd contents, microbial biomass carbon （C） content and the organic C mineralization rate of the soils in a long-term trace metal-contaminated paddy region of Guangdong, China were determined to assess the sensitivity of microbial indices to moderately metal-contaminated paddy soils. The mean contents of total Cu, Zn, Pb and Cd were 251, 250, 171, and 2.4 mg kg^-1 respectively. DTPA-extractable metals were correlated positively and significantly with total metals, CEC, and organic C （except for DTPA-extractable Cd）, while they were negatively and highly significantly correlated with pH, totall Fe and mn. metal stress resulted in relatively low ratios of microbial biomass C to organic C and in remarkable inhibition of the microbial metabolic quotient and C mineralization rate, which eventually led to increases in soil organic C and C/N. moreover, microbial respiratory activity showed a stronger correlation to DTPA-extractable metals than to total metal content. Likewise, in the acid paddy soils some “linked” microbial activity indices, such as metabolic quotient and ratios of basal respiration to organic C, especially during initial incubation, were found to be more sensitive indicators of soil trace metal contamination than microbial biomass C or basal respiration alone.

关键词： availability indication microbial characteristics trace metals

Abundance of insects and aerial insectivorous birds in relation to pesticide and fertilizer use

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Avian Research 2021年第3期12卷 412-420页

作者： Anders Pape møller Dorota Czeszczewik Einar Flensted-Jensen Johannes Erritzøe Indrikis Krams Karsten Laursen Wei Liang Wiesław Walankiewicz Ecologie Systématique Evolution UniversitéParis-SudCNRSAgroParisTechUniversitéParis-Saclay91405 Orsay CedexFrance ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing 100875China Faculty of Exact and Natural Sciences Institute of Biological SciencesSiedlce University of Natural Sciences and Humanitiesul.B.Prusa 1408-110 SiedlcePoland Cypresvej 1 9700 BrønderslevDenmark House of Bird Research Taps6070 ChristiansfeldDenmark Department of Biotechnology Daugavpils UniversityDaugavpils 5401Latvia Department of Bioscience Aarhus UniversityGrenåvej 148410 RøndeDenmark ministry of Education Key Laboratory for Ecology of Tropical Islands Key Laboratory of Tropical Animal and Plant Ecology of Hainan ProvinceCollege of Life SciencesHainan Normal UniversityHaikou 571158China

Background:The abundance of insects has decreased considerably during recent decades,resulting in current abundance showing 70-80%reductions in more than 15 studies across temperate climate *** reduc-tions in the abundance of insects are likely to have consequences for other taxa at higher trophic levels such as preda-tors and ***,fertilizers and agricultural land use are likely candidates accounting for such reductions in the abundance of ***:Here we surveyed the abundance of flying insects,and the reduction in the abundance of insects as a consequence of intensive reduction in agricultural practice linked to fertilizer use and pesticide *** we dem-onstrated consistency in abundance of birds among study ***:We demonstrated that the use of fertilizers and pesticides had reduced the abundance of insects,with consequences for the abundance of insectivorous bird species such as Barn Swallows(Hirundo rustica),House martins(Delichon urbicum)and Swifts(Apus apus).Juvenile Barn Swallows were negatively affected by the reduced abundance of insects and hence the reproductive success of insectivorous bird *** effects imply that the abundance of insects could be reduced by the availability of insect ***:These effects of intensive agriculture on insect food abundance are likely to have negative impacts on populations of insects and their avian *** hypothesis was validated by a reduction in the abundance of insects,linked to an increase in the abundance of fertilizers and a general change in farming practice.

关键词： Aerial insectivores Fecundity of insects Insect abundance Insectivores,Insects

疑似急性冠状动脉综合征病人行CT血管成像后的远期疗效

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国际医学放射学杂志 2014年第6期 572-573页

作者： A.Nasis I.T.meredith P.S.sud J.D.Cameron J.m.Troupis S.K.Seneviratne 石彦姝 monash Cardiovascular Research Centre Monash-HEARTMonash Health and Monash University Department of Medicine(MMC)246 Clayton RdClayton 3168Australia

摘要目的评估疑似急性冠状动脉综合征(ACS)的急诊病人行CT血管成像引导下治疗后的远期疗效及再入院率。材料与方法本研究经伦理委员会批准,所有病人均签署

关键词：急性冠状动脉综合征血管成像病人远期疗效 CT

A positron source using an axially oriented crystal associated to a granular amorphous converter

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Chinese Physics C 2012年第9期36卷 871-878页

作者：徐成海 Robert Chehab Peter Sievers Xavier Artru michel Chevallier Olivier Dadoun 裴国玺 Vladimir m.Strakhovenko Alessandro Variola Institute of High Energy Physics Chinese Academy of Sciences Laboratoire de l'Accélérateur Linéaire IN2P3/CNRS et Université de Paris-SudBP 34-91898Orsay cedexFrance Institut de Physique Nucléaire de Lyon IN2P3/CNRS et Université Lyon 169622 VilleurbanneFrance CERN CH-1211Genéve 23Switzerland Budker Institute of Nuclear Physics Av.Lavrentyeva11630090 NovosibirskRussia

A non-conventional positron source using the intense y radiation from an axially oriented monocrys- tal which materializes into e^＋e^- pairs in a granular amorphous converter is described. The enhancement of photon radiation by multi-GeV electrons crossing a tungsten crystal along its 〈111〉 axis is reported. The resulting enhancement of pair production in an amorphous converter placed 2 meters downstream, is also re- ported. Sweeping off the charged particles from the crystal by a bending magnet upstream of the converter allows a significant reduction of the deposited energy density. Substituting a granular target made of small spheres for the usual compact one, makes the energy dissipation easier. The deposited energy and correspond- ing heating are analyzed and solutions for cooling are proposed. The configurations studied here for this kind of positron source allow its consideration for unpolarized positrons for the ILC.

关键词： channeling effect crystal positron source ILC

Latest results from GraAL collaboration

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Chinese Physics C 2009年第12期33卷 1249-1253页

作者： V. Vegna V. Bellini J.P. Bouquet L. Casano A. D'Angelo J.P. Didelez R. Di Salvo A. Fantini D. Franco G. Gervino F. Ghio G. Giardina B. Girolami A. Giusa m. Guidal E. Hourany A.S. Ignatov R. Kunnel A. Lapik A. Lleres P. Levi Sandri F. mammoliti G. mandaglio m. manganaro m. moricciani A.N. mushkarenkov V.G. Nedorezov C. randieri D. Rebreyend N.V. Rudnev G. Russo C. Schaerf m.L. Sperduto m.C. Sutera.a.Turinge Dip. di Fisica Università degli Studi di Roma 'Tor Vergata' via della Ricerca Scientifica 1 I-00133 Roma Italy INFN - Sezione di Roma 'Tor Vergata' via della Ricerca Scientifica 1 I-00133 Roma Italy Dip. di Fisica e Astronomia Università di Catania via Santa Sofia 44 I-95123 Catania Italy INFN - Sezione di Catania via Santa Sofia 44 I-95123 Catania Italy LPSC Universit Joseph Fourier Grenoble 1 CNRS/IN2P3 Institut National Polytechnique de Grenoble 53 Avenue des Martyres 38026 Grenoble France IPNO Universit de Paris-Sud 11 CNRS/IN2P3 15 rue Georges Clemenceau 91406 Orsay France Dip. di Fisica Sperimentale Università di Torino via P.Giuria I-00125 Torino Italy INFN - Sezione di Torino via P.Giuria I-00125 Torino Italy Istituto Superiore di Sanità viale Regina Elena 299 I-00161 Roma Italy INFN - Sezione di Roma piazzale Aldo Moro 2 I-00185 Roma Italy Dip. di Fisica Universitàdi Messina salita Sperone 31 I-98166 Messina Italy Institute for Nuclear Research RAS 117312 Moscow Russia INFN - Laboratori Nazionali di Frascati via E.Fermi 40 I-00044 Frascati Italy INFN - Sezione di Catania via Santa Sofia 44 I-95123 Catania Italy

The GraAL experimental set-up consists of a polarized and tagged photon beam that covers an energy range from a minimum of 600 meV up to a maximum of 1500 meV, of a liquid Hydrogen or Deuterium target and of the 4π Lagrange detector optimized for photon detection. It allows the study of pseudo-scalar and vector meson photoproduCtion on the nucleon in the energy range corresponding to the second and the third resonance regions. In the following, the ∑ beam asymmetries in η and π0 photoproduction on quasi-free nucleon are shown. Also single and double polarization observables in K＋A photoproduction on free proton are shown; they are important to confirm the role of new or poorly known resonances in the 1900 meV mass region.

关键词： polarized photon meson photoproduction polarization observables

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二阶非线性maker条纹测试及模拟

硅酸盐学报 2010年第11期38卷 2050-2053页

作者：何漩刘启明赵修建 POUmECCEC B LANCRY m 武汉理工大学硅酸盐材料工程教育部重点实验室武汉430070 Laboratoire de Physico-Chimie de l'Etat Solide UMR CNRS-UPS 8648Universit6 de Paris SudBat.41491405Orsay CedexFrance

据maxwell方程及电磁波在界面上的边界条件,采用math CAD软件对1064 nm基频光在二阶非线性介质中的传播进行maker条纹模拟,得到二阶非线性介质中产生532nm倍频光的强度模拟公式。同时对倍频晶体材料、电场/温度场极化后玻璃的实验maker... 详细信息

据maxwell方程及电磁波在界面上的边界条件,采用math CAD软件对1064 nm基频光在二阶非线性介质中的传播进行maker条纹模拟,得到二阶非线性介质中产生532nm倍频光的强度模拟公式。同时对倍频晶体材料、电场/温度场极化后玻璃的实验maker条纹测试结果与理论结果进行比较。结果表明:倍频晶体的maker测量结果与模拟相吻合;对电场/温度场极化玻璃样品的模拟结果,在一定范围内与测量结果相一致。理论模拟可对样品制备、maker条纹测试及二阶非线性极化机理探讨具有一定的指导意义。

关键词： maxwell方程 math计算机辅助设计软件 maker条纹测试二阶非线性

Assessing Post-Conflict Challenges and Opportunities of the Animal-Agriculture System in the Alpine Region of Uvira District in sud-Kivu Province, D. R. Congo

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American Journal of Plant Sciences 2014年第20期5卷 2948-2955页

作者： m. m. D. Katunga J.-B. muhigwa International Center for Tropical Agriculture (CIAT) Bukavu D. R. Congo Current Address: National Institute of Agriculture Studies and Research (INEra) mulungu Bukavu D. R. Congo Universite Officielle de Bukavu Bukavu R. D. Congo

The Alpine region of Uvira District in South-Kivu Province faces low agricultural productivity challenges largely due to human population pressure on the natural resource base. During the dry season, conflicts between crop farmers and livestock breeders are common. This region is located 2500 - 3020 m a.s.l. and is almost inaccessible due to poor road infrastructure. To understand the interactions between natural resources (forests, pastures, soils) and sedentary agriculture, and to propose solutions for sustainable natural resource management, Participatory Rural Appraisal (Pra) sessions covering three farmer group interviews were conducted in July 2010 in marungu, Kitembe and Kahololo location. The livelihoods of the Banyamulenge have been transformed from pastoralism to a sedentary system with the introduction of crop cultivation after 1980. maize, bush beans and Irish potatoes are cultivated with limited success because of late crop maturity under the prevailing climatic conditions. Livestock, mainly cattle, sheep and goats is managed under extensive system, relying on natural pasture far from the human settlements. Livestock plays an important role to define people’s wealth and is mainly managed by men. There is a real need of forages during the dry season;however, cultivation of forages is unknown. On the other hand, pastures appear to be degenerating due to overgrazing. Access by farmers to efficient and effective agricultural extension services is fundamental in order to promote locally adapted and profitable crop and livestock production while at the same time, sustaining the productive resource base and security.

关键词： Livestock Agriculture Alpine Region D. R. Congo