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International Journal of Sediment Research 2021年第2期36卷 317-327页

作者： michel Michaelovitch de Mahiques Samara Cazzoli y Goya Maria Carolina da Silva Nogueira de Matos Rodrigo Augusto Udenal de Oliveira Bianca Sung Mi Kim Paulo Alves de Lima Ferreira Rubens Cesar Lopes Figueira Marcia Caruso Bícego Oceanographic Institute University of S?o Paulo Pra?a do Oceanográfico Institute of Energy and Environment University of S?o Paulo Avenida Professor Luciano Gualberto

The current study aims to do a comparative analysis of the results obtained with two End-Member(EM)grain-size modeling techniques(Analy Size and Bas EMMA) and the Environmental Sensitive Grain-Size(ESGS) modeling for sediment samples collected in the mudbelts of the southern brazilian shelf. The methods were compared using grain-size data from the south brazilian shelf, and the results are discussed here. It is the first time that the concept of ESGS, in its present form, is utilized outside China. The results show that despite its relative ease of use, the ESGS is not fully comparable to the EM analyses, and only two grain-size ESGS classes were recognized as analogous to EMs. The comparison of the Analy Size and Bas EMMA procedures also revealed significant differences between the techniques. A comparative analysis between the two EM techniques revealed advantages in the Bas EMMA, especially in the better correlation of the end-members with the original grain size distribution. The analysis of the geographical distribution of the EM abundances allowed point sources of sandy populations to be recognized as well as the contribution of the Rio de la Plata as a source of silty sediments to be inferred.

关键词： Grain-size End-member Environmentally sensitive Mudbelt Continental shelf

classification of Sandstone-Related Uranium deposits

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Journal of Earth Science 2022年第2期33卷 236-256页

作者： michel Cuney Julien Mercadier Christophe Bonnetti Universitéde Lorraine GéoRessourcesCNRSCREGUNancy F54500France 2.State Key Laboratory of Nuclear Resources and EnvironmentEast China University of TechnologyNanchang 330013China

Sandstone type deposits are the most common type of uranium deposits in the world.A large variety of sub-types have been defined,based either on the morphology of the deposits(e.g.,tabular,roll front,etc),or on the sedimentological setting(e.g.,paleovalley,paleochannel,unconformity),or on tectonic or lithologic controls(e.g.,tectonolithologic,mafic dykes/sills),or still on a variety of others characteristics(phreatic oxidation type,interlayer permeable type,multi-element stratabound infiltrational,solution front limb deposit,humate type,etc.),reflecting the diversity of the characteristics of these deposits,but making it difficult to have a clear overview of these ***,uranium deposits occurring in the same sedimentological setting(e.g.,paleochannel),presenting similar morphologies(e.g.,tabular),may result from different genetic mechanisms and thus can be misleading for exploration *** aim of the present paper is to propose a new view on sandstone-related uranium deposits combining both genetic and descriptive *** dual view is indeed of primordial importance because all the critical characteristics of each deposit type,not limited to the morphology/geometry of the ore bodies and their relationships with depositional environments of the sandstone,have to be taken into account to propose a comprehensive classification of uranium *** this respect,several key ore-forming processes,like the physical-chemical characteristics of the mineralizing fluid,have to be used to integrate genetic aspects in the *** a succession of concentration steps,potentially temporally-disconnected,are involved in the genesis of some uranium mineralization,the classification here proposed will focus on the main mechanisms responsible for the formation and/or the location of ore *** objective of this paper is also to propose a robust and widely usable terminology to define and categorize sandstone uranium deposits,considering

关键词： sandstone uranium genetic classification redox control depositional environment fluids ore deposit geology

An improved method to assess the required strength of cemented backfill in underground stopes with an open face

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International Journal of Mining Science and Technology 2014年第4期24卷 549-558页

作者： Li Li michel Aubertin department of Civil Geological and Mining Engineering Ecole Polytechnique de MontréalMontreal H3C 3A7 Canada

Backfill is increasingly used in underground mines to reduce the surface impact from the wastes produced by the mining operations. But the main objectives of backfilling are to improve ground stability and reduce ore dilution. To this end, the backfill in a stope must possess a minimum strength to remain self-standing during mining of an adjacent stope. This required strength is often estimated using a solution proposed by Mitchell and co-workers, which was based on a limit equilibrium analysis of a wedge exposed by the open face. In this paper, three dimensional numerical simulations have been performed to assess the behavior of the wedge model. A new limit equilibrium solution is proposed, based on the backfill displacements obtained from the simulations. Comparisons are made between the proposed solution and experimental and numerical modeling results. Compared with the previous solution, a better agreement is obtained between the new solution and experimental results for the required cohesion and factor of safety. For large scale(field) conditions, the results also show that the required strength obtained from the proposed solution corresponds quite well to the simulated backfill response.

关键词： Underground mines Backfill Required strength Analytical solutions Numerical modeling Mitchell's solution

High Order Compact Schemes in Projection Methods for Incompressible Viscous Flows

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Communications in Computational Physics 2011年第4期9卷 994-1019页

作者： michel Fournie Alain Rigal Institut de Mathematiques de Toulouse Universite de Toulouse et CNRS(UMR 5219)France

Within the projection schemes for the incompressible Navier-Stokes equations(namely"pressure-correction"method),we consider the simplest method(of order one in time)which takes into account the pressure in both steps of the splitting *** this scheme,we construct,analyze and implement a new high order compact spatial approximation on nonstaggered *** approach yields a fourth order accuracy in space with an optimal treatment of the boundary conditions(without error on the velocity)which could be extended to more general *** prove the unconditional stability of the associated Cauchy problem via von Neumann *** we carry out a normal mode analysis so as to obtain more precise results about the behavior of the numerical *** we present detailed numerical tests for the Stokes and the Navier-Stokes equations(including the driven cavity benchmark)to illustrate the theoretical results.

关键词： Incompressible Navier-Stokes fractional step method high order compact scheme boundary conditions

Biomarkers for detection of alcohol consumption in liver transplantation

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World Journal of Gastroenterology 2016年第14期22卷 3725-3734页

作者： Katharina Staufer michel Yegles Division of Transplantation Department of Surgery Medical University of Vienna 1090 Vienna Austria Laboratoire National de Sante Service de Toxicologie medico-legale 1 rue Louis Rech L-3555 Dudelange Luxembourg

Alcoholic liver disease is an established, yet controversial, indication for liver transplantation. Although an abstinence period of up to 6 mo prior to transplantation is mandatory, alcohol relapse after transplantation is a common event. In case of recurrence of heavy drinking, graft survival is significantly impaired. Guidelines on detection and surveillance of alcohol consumption in this patient cohort are lacking. This review summarizes the challenge of patient selection as well as the current knowledge on established and novel alcohol biomarkers with special focus on liver transplant candidates and recipients.

关键词： Ethyl glucuronide Liver cirrhosis Short-term alcohol markers Long-term alcohol markers Psychological support

Numerical micro-texture optimization for lubricated contacts-A critical discussion

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Friction 2022年第11期10卷 1772-1809页

作者： Max MARIAN Andreas ALMQVIST Andreas ROSENKRANZ michel FILLON department of Mechanical and Metallurgical Engineering Pontificia Universidad Católica de ChileSantiago 690411Chile Division of Machine Elements LuleåUniversity of TechnologyLuleåSE-97187Sweden department of Chemical Engineering Biotechnology and MaterialsFCFMUniversity of ChileSantiago 8370456Chile Institut Pprime CNRSUniversity of PoitiersPoitiers Cedex TSA 4112386073France

despite numerous experimental and theoretical studies reported in the literature,surface micro-texturing to control friction and wear in lubricated tribo-contacts is still in the trial-and-error *** tribological behaviour and advantageous micro-texture geometries and arrangements largely depend on the contact type and the operating *** scale implementation is hampered by the complexity of numerical *** substantiates the urgent need to numerically design and optimize micro-textures for specific *** these aspects have not been covered by other review articles yet,we aim at summarizing the existing state-of–the art regarding optimization strategies for micro-textures applied in hydrodynamically and elastohydrodynamically lubricated *** analysis demonstrates the great potential of optimization strategies to further tailor micro-textures with the overall aim to reduce friction and wear,thus contributing toward an improved energy efficiency and sustainability.

关键词： micro-texturing hydrodynamics elastohydrodynamics tribo-simulation optimization

Cholesterol confusion and statin controversy

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World Journal of Cardiology 2015年第7期7卷 404-409页

作者： Robert DuBroff michel de Lorgeril department of Medicine Division of CardiologyUniversity of New Mexico School of MedicineMSC 10-55501 University of New Mexico PRETA-TIMC-IMAG Equipe Coeur and NutritionCNRS UMR 5525-UJF-INPFacultéde MédecineDomaine de la MerciUniversitéde Grenoble

The role of blood cholesterol levels in coronary heart disease(CHD) and the true effect of cholesterollowering statin drugs are debatable. In particular,whether statins actually decrease cardiac mortality and increase life expectancy is controversial. Concurrently,the Mediterranean diet model has been shown to prolong life and reduce the risk of diabetes,cancer,and CHD. We herein review current data related to both statins and the Mediterranean diet. We conclude that the expectation that CHD could be prevented or eliminated by simply reducing cholesterol appears unfounded. On the contrary,we should acknowledge the inconsistencies of the cholesterol theory and recognize the proven benefits of a healthy lifestyle incorporating a Mediterranean diet to prevent CHD.

关键词： Cholesterol Statins Coronary heart disease Mediterranean diet Cardiovascular disease Mortality

Effect of presence of lifting pocket on the THD performance of a large tilting-pad thrust bearing

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Friction 2015年第4期3卷 266-274页

作者： michel FILLON MichałWODTKE MichałWASILCZUK Institut Pprime CNRS-Universitéde Poitiers-ISAE-ENSMADépartement Génie Mécanique et Systèmes ComplexesBP 30169SP2MI86962 Futuroscope Chasseneuil CedexFrance Faculty of Mechanical Engineering Gdansk University of TechnologyGdanskPoland

Hydrostatic assistance is a commonly used method to improve limited load carrying ability of tilting-pad thrust bearings during transient states of operation of vertical shaft *** of special hydraulic equipment(as pumps,valves,etc.),it also requires manufacturing of special recesses/pockets at pad sliding surfaces,into which oil is injected under high *** allows to lift the rotor before start-up of the machine and form a hydrostatic film between pads and *** is a quite wide variety of geometry of recesses(shape,depth,and size)met in practical large bearing *** presence of a hydrostatic pocket(usually located in the sliding surface above the pivot area,where thin film,high oil pressure and temperature are observed)affects bearing performance under hydrodynamic *** theoretical researches,there is an almost common practice not to include hydrostatic recess in thermohydrodynamic(THD)or thermoelastohydrodynamic(TEHD)*** is probably due to the problems with obtaining solution for oil film geometry with pocket,the order of magnitude of the pocket depths being larger than gap *** this paper,an attempt was taken to study the effect of lifting pocket on THD performance of a large tilting-pad thrust bearing of Itaipu power *** performance was evaluated including recess shape for several cases of its *** results show that hydrostatic recess changes calculated bearing properties quite significantly,especially in vicinity of the pocket.

关键词： lifting pocket tilting-pad thrust bearing THD regime numerical simulations

A Stein deficit for the logarithmic Sobolev inequality

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Science China Mathematics 2017年第7期60卷 1163-1180页

作者： LEDOUX michel NOURDIN Ivan PECCATI Giovanni Institut de Mathematiques de Toulouse Universite de Toulouse-Paul-Sabatier Toulouse F-31062 France Institut Universitaire de France UR en Mathematiques-FSTC Luxembourg University Luxembourg City L-1359 Luxembourg

We provide some lower bounds on the deficit in the Gaussian logarithmic Sobolev inequality in terms of the so-called Stein characterization of the Gaussian *** techniques are based on the representation of the relative Fisher information along the Ornstein-Uhlenbeck semigroup by the Minimum Mean-Square Error from information theory.

关键词： deficit logarithmic Sobolev inequality Ornstein-Uhlenbeck semigroup minimum mean-square error Stein kernel

Late-entry commercial thinning effects on Pinus banksiana:growth, yield, and stand dynamics in Québec, Canada

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Journal of Forestry Research 2019年第1期30卷 95-106页

作者： Martin-michel Gauthier Stéphane Tremblay Ministère des Forêts de la Faune et des Parcs du Québec Natural Resources Canada Canadian Forest Service

We studied late-entry commercial thinning effects on growth, yield, and regeneration in a 48-year-old jack pine(Pinus banksiana Lamb.) stand. Applied thinning intensities were 27, 32, and 47% of merchantable basal area(BA) excluding skidding trails. After 15 years, mean diameter at breast height of surviving trees in the 47% BA removal increased by 4.9 cm(25%) compared to the unthinned control. The 47% BA removal also increased gross merchantable volume(GMV) tree-1by 46% compared to the control. The 27% BA removal had twice as much GMV ha-1compared to the 47% BA removal after15 years. Moreover, cumulative GMV ha-1was much higher in the 27% BA removal than in the unthinned control. The highest thinning intensity produced larger trees on average, while the lowest thinning intensity maximized volume production per hectare. Maintenance of acceptable growing stock throughout the 15-year period in the 27% BA removal could provide other ecosystem functions such as biodiversity enhancement or wildlife habitat by delaying senescence. Regeneration data showed that a shift in species composition occurred in the understory. After 15 years, the understory was dominated by black spruce(Picea mariana(Mill.) B.S.P.), white birch(Betula papyrifera Marsh.), and trembling aspen(Populus tremuloides Michx.). If regenerating jack pine is an objective after final overstory removal, additional efforts will be needed to re-establish this species.

关键词： Jack pine Commercial thinning Stand yield Succession delayed senescence Tree regeneration