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ENSO impacts on litter stocks and water holding capacity in secondary forests in eastern Amazonia

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Journal of Forestry Research 2024年第1期35卷 83-89页

作者： Julia Isabella de Matos Rodrigues Walmer Bruno Rocha Martins Victor Pereira de Oliveira Myriam Suelen da Silva Wanzerley hélio Brito dos Santos Júnior Francisco de Assis Oliveira Graduate Program in Forestry Sciences Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Av.Presidente Tancredo Neves2501BelémPará66077-530Brazil Federal Rural University of Amazonia Tv.Pau-AmareloCapitão PoçoPará68650-000Brazil National Institute of Amazonia Research Av.Constelação Cruzeiro do SulManausAmazonas 69060-062Brazil

Among the impacts of climate change,there is the intensification of phenomena such as the El Niño South-ern Oscillation(ENSO)responsible for El Niño and La Niñ***,understanding their effects on the functional pro-cesses of forests is ***,this study evaluated the effects of ENSO on litter stock and water holding capac-ity(WhC)in a successional forest in eastern *** occurred in periods with the most rainfall in El Niño(2019)and least in La Niña(2021)*** permanent plots were used to sample *** effects were evident for WhC,higher during El Niñ***,this influence was not clear for litter,as only in the rainy season effects were *** was a positive correlation of WhC with precipitation and humidity,while litter stocks were negatively correlated with temperature and wind *** the subject of this study requires long-term assessments,preliminary results suggests that,depending on the intensity of ENSO,forest functional processes can be strongly impacted and *** conclusion reinforces warnings by the scientific community about the impacts of climate change on the maintenance of litter stocks,decomposition and,consequently,the biogeochemical cycle and essential ecosystem services for the maintenance of Amazonia *** need to develop long-term research to understand the effects of climatic change on litter stocks and water holding capacity is highlighted,especially in Amazonia.

关键词： Seasonality Climate change Succession ecosystem Biogeochemical cycle Amazonia biodiversity

Microstructural evolution and grain growth mechanism of pre-twinned magnesium alloy during annealing

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Journal of Magnesium and Alloys 2021年第4期9卷 1238-1251页

作者： Ye Jin Kim Jong Un Lee Young Min Kim Sung hyuk par School of Materials Science and Engineering Kyungpook National JJniversityDaegu 41566Republic of Korea Implementation Research Division Korea Institute of Materials ScienceChanson 51508Republic of Korea

The microstructural evolution and underlying grain growth mechanism of a{1012}-twin-containing Mg alloy during annealing are investigated through quasi in situ electron backscatter diffraction measurements of a rolled AZ31 alloy subjected to precompression along the rolling direction(RD).The precompressed material shows a partially twinned structure consisting of a twinned region and a residual matrix region,and this structure changes to an almost twin-free structure consisting of grown grains with serrated grain boundaries in twinand matrix-originated regions after annealing at 250℃ for 1 *** addition,the average grain size almost doubles and the internal strain energy decreases significantly after *** microstructural variations are induced mainly by grain growth through the strain-induced migration of high-angle grain boundaries without the movement of twin *** twinned region of the precompressed material has higher stored strain energy than the residual matrix region because the crystallographic orientation of the former region is favorable for basal slip and because of the occurrence of the dislocation transmutation reaction in the *** reducing the total strain energy accumulated in the precompressed material,the residual matrix region—having lower stored strain energy—preferentially grows while consuming the twinned regions formed in the surrounding grains during *** a result,the area fraction of grains with a matrix texture increases whereas that of grains with a twin texture decreases after *** twin texture intensity increases significantly and this texture becomes more concentrated along the RD because the highly RD oriented twins tend to grow during annealing on account of their fairly low stored strain energy.

关键词： Magnesium Twin Annealing Grain growth Strain energy

Ecosystem management in paludified boreal forests:enhancing wood production,biodiversity,and carbon sequestration at the landscape level

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Forest Ecosystems 2018年第4期5卷 376-389页

作者： Benoit Lafleur Nicole J.Fenton Martin Simard Alain Leduc David paré Osvaldo Valeria Yves Bergeron NSERC-UQAT-UQAM Industrial Chair in Sustainable Forest Management and Institut de recherche sur les forêts Université du Québec en Abitibi-Témiscamingue445boul.de I'UniversiteRouyn-NorandaQC J9X 5E4Canada Department of Geography Laval UniversityQuebecQC GIV 0A6Canada Centre d'etude de la foret Universite du Quebec a Montreal141 Avenue du President-KennedyMontrealQC H2X IY4Canada Ressources Naturelles Canada Service canadien des forets Centre de foresterie des Laurentides1055du P.E P S.P.O.13ox 3800QuebecQC GIV 4C7Canada

Canada’s boreal forest represents an important contributor of the world’s wood supply industry. however,maintaining or increasing productivity of the boreal forest may be challenging in areas dominated by forested peatlands. Moreover, sustainable management of these forests must also consider other important aspects of the forest ecosystem such as biodiversity and carbon sequestration. To address these concerns, ecosystem-based management has been implemented in some Canadian jurisdictions, such as in regions where a large portion of the boreal forest is dominated by forested peatlands. The objectives of this paper are(1) to summarize our current understanding of how natural disturbances influence stand dynamics and biodiversity in forested peatlands, and(2) to review the main differences between natural and managed forest stands with respect to soil properties, stand productivity, understory plant communities. We also discuss how even-age management regime succeeds or fails to preserve old forests and how this loss affects both forest structure and habitat diversity at the landscape *** conclude by showing how, in boreal forested peatlands, forest management could contribute to carbon sequestration and mitigate projected climate change.

关键词： Clearcutting Fire Forest dynamics partial cutting Soil properties Stand productivity Understory plant

Grippe aviaire : tout ce qu'il faut savoir

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法语国家与地区研究 2006年第1期 61-64页

作者： par Claudia Cornwall

Qu’est-ce que la grippe ?Il s’agit d’une infection respiratoire d’origine virale, hautement contagieuse, qui se transmet entre individus par voie dite aérienne (toux, éternuement). On distingue trois grands groupes de virus de la grippe : A, B et C. Ceux de type A, qui affectent les canards, poulets, porcs et baleines, mais aussi les hommes, sont les plus *** surface des virus est hérissée de spicules, dont les virus A et B comportent deux types : l’hémagglutinine (hA) et la neuraminidase (NA), également appelées protéines de surface. Les chercheurs ont identifié 16 sous-types de hA et 9 sous-types de NA, ce qui donne au total 144 combinaisons possibles de virus grippaux de type A. Mais seules 3 combinaisons (h1N1, h1N2, h3N2) se transmettent d’homme  homme  ce jour.

关键词： Grippe aviaire

CFD study of non-premixed swirling burners: Effect of turbulence models

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1029-1038页

作者： Erfan Khodabandeh hesam Moghadasi Mohsen Saffari Pour Mikael Ersson par G.Jonsson Marc A.Rosen Alireza Rahbari Department of Mechanical Engineering Amirkabir University of TechnologyTehranIran School of Mechanical Engineering Department of Energy ConversionIran University of Sciesnce and Technology(IUST)Narmak 16846-13114TehranIran Department of Mechanical Engineering Shahid Bahonar University of KermanKermanIran Division of Processes Department of Materials Science and EngineeringKTH Royal Institute of TechnologyBrinellvägen 23SE-10044 StockholmSweden Faculty of Engineering and Applied Science University of Ontario Institute of TechnologyOshawaOntarioL1H 7K4Canada Department of Mechanical Engineering Shahid Rajaee Teacher Training University(SRTTU)TehranIran Research School of Engineering The Australian National UniversityCanberraACT 2601Australia

This research investigates a numerical simulation of swirling turbulent non-premixed *** effects on the combustion characteristics are examined with three turbulence models:namely as the Reynolds stress model,spectral turbulence analysis and Re-Normalization *** addition,the P-1 and discrete ordinate(DO)models are used to simulate the radiative heat transfer in this *** governing equations associated with the required boundary conditions are solved using the numerical *** accuracy of this model is validated with the published experimental data and the comparison elucidates that there is a reasonable agreement between the obtained values from this model and the corresponding experimental *** different models proposed in this research,the Reynolds stress model with the Probability Density Function(PDF)approach is more accurate(nearly up to 50%)than other turbulent models for a swirling flow *** the effect of radiative heat transfer model,it is observed that the discrete ordinate model is more precise than the P-1 model in anticipating the experimental *** model is able to simulate the subcritical nature of the isothermal flow as well as the size and shape of the internal recirculation induced by the swirl due to combustion.

关键词： Computational Fluid Dynamics(CFD) Turbulent combustion Non-premixed flames Large eddy simulations Radiative heat transfer model Modeling validation

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LE BIEN ET LE MAL

法国研究 1985年第4期 26-30页

作者： par Wang Tai Lai-La modernitéchez Victor hugo…

Au cours de mis au point de ma présente étude,j′ai change de titrequi était DECOUVERTE *** hésitation peut s′expli-quer par le fait que ma communication a été préparée à partir de deuxséries d′interrogati... 详细信息

关键词：责任编辑

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假如地球找不到北(1)

法语学习 2004年第6期 67-72页

作者： par hélène Guillemot 徐伟民

根据间隔 2 0年的人造卫星测量 ,地球磁场迅速衰减。我们是否将重新遭遇地球曾经历过的磁场颠倒 ?

关键词：法语科技文阅读双语阅读对照读物

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白喉诊断上之拭喉法

中华医学杂志 1935年第6期21卷 647-648页

作者： h.J.parísh 戴天右

作者由应用Folger氏之拭喉法所得之经验,证明此法於白喉之早期诊断颇有相当价值。所用方法,系就 Foloer氏之原有方法略加变更。其法如下:用普通已消毒之棉花拭子醮正常马(或牛)血清(末经冲淡,加热或加有防腐剂者);将拭子靠於玻管

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Fundamental solutions for axi-symmetric translational motionof a microstretch fluid

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Acta Mechanica Sinica 2012年第3期28卷 605-611页

作者： h.h.Sherief M.S.Faltas E.A.Ashmawy Department of Mathematics Faculty of ScienceAlexandria University

The fundamental solution for the axi-symmetric translational motion of a microstretch fluid due to a concen- trated point body force is obtained. A general formula for the drag force exerted by the fluid on an axi-symmetric rigid par- ticle translating in it is then deduced. As an application to the obtained drag formula, this paper has discussed the problem of creeping translational motion of a rigid sphere in a mi- crostretch fluid. The slip boundary condition on the surface of the spherical particle is applied. The drag force and the other physical quantities are obtained and represented graph- ically for various values of the micropolarity and slip param- eters.

关键词： Drag force Fundamental solution Mi-crostretch fluid Slip condition