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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： Pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot julien g.moreau Jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

Phase Invariant Proper Orthogonal Decomposition for the Study of a Compressed Vortex

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Journal of Thermal Science 2005年第2期14卷 108-113页

作者： julien moreau Mark FOgLEMAN g.CHARNAY J.BOREE Institut de Mécanique des Fluides UMR CNRS/INPT-UPS 5502 Allée du Pr Soula 31400 Toulouse FranceCornell University IthacaNew York 14853U.S.A.Institut de Mécanique des Fluides UMR CNRS/INPT-UPS 5502 Allée du Pr Soula 31400 ToulouseFranceLEA ENSMA UMR 6609 CNRS Futuroscope France

We propose here an experimental investigation of a vortex submitted to a radial perturbation while being compressed. This experiment reproduces a model situation of the complex flows that take place in a real engine cylinder. An isolated tumbling flow is first submitted to an injection of fluid and then compressed and measurements are realised by Particle Image Velocimetry (PIV). The Proper Orthogonal Decomposition is known to be an unbiased method to identify the coherent structures of turbulent flows. It is possible to make this decomposition for a given phase or to create a set of basis functions with the whole set of compression stroke velocity ***, the experimental set-up will be presented, then the second part provides the POD principle. Results of phased POD decomposition of the compression of the unperturbated vortex will be presented. Finally results from the time invariant POD will be discussed to study the influence of the jet perturbation in the compression of a vortex.

关键词： turbulence POD PIV cycle to cycle fluctuations.

Discrete element method simulation of segregation pattern in a sinter cooler charging chute system

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Particuology 2021年第6期19卷 34-42页

作者： Edouard Izard Maxime moreau Pascal Ravier Arcelor Mittal global RfyD Voie RomaineBP3032057283 Maizieres-les-Metz CedexFrance Arcelor Mittal Mediterranee 13776 Fos-sur-MerFrance

This paper presents the simulation of material flows in the large-scale charging chute of Fos-Sur-Mer sinter cooler plant by using three-dimensional Discrete Element Method(DEM).As a result of granular flows in the chute,segregation patterns are formed at the charging *** sinter material is modelled as dry particles and their size distribution in the simulation is larger than in the reality to keep the simulation in a reasonable run *** calibration tests are performed to specify the DEM contact parameters in order to replicate the behavior observed during experiments with the virtual sinter *** DEM model is found to be in good agreement with a segregation measurement.A sensitivity analysis using different particle sizes shows that the segregation patterns are not affected by the different sizes used for fine ***,the filling ratio in the charging system is varied in the model and shows that a high filling ratio leads to less segregation when exiting the charging *** DEM model is used to analyze the granular flows in the charging chute,understand the material behavior and optimize the sinter cooling efficiency.

关键词： Discrete element method Segregation Sinter Industrial application

Alleviation of Subsoil Acidity of Red Soil in Southeast China with Lime and gypsum *1

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Pedosphere 1998年第2期8卷 113-120页

作者： SUNBO R．moreau 等 InstituteofSoilScience TheChineseAcademyofSciencesP.O.Box821Nanjing210008（China） ORSTOM，911，avenu

Application of lime or gypsum is a common agricultural practice to ameliorate soils with low pH which prohibits crop production. Its integrated effect on soil properties in a red soil derived from Quaternary red clay in Southeast China is discussed in this paper. Application of gypsum in the topsoil without leaching raised soil pH and promoted the production of soil NH 4, but lime addition had a contrary effect. generally, application of lime and/or gypsum has little effect on soil electrical properties. gypsum had a little effect on soil exchange complex and its effect went down to 30 cm in depth. The effect of lime reached only to 5 cm below its application layer. With leaching, Ca transferred from top soil to subsoil and decreased exchangeable Al in subsoil. gypsum application led to a sharp decrease in soil exchangeable Mg but had no effect on K.

关键词： alleviation gypsum lime red soil subsoil acidity

Spatial distribution of Vespa velutina individuals hunting at domestic honeybee hives： heterogeneity at a local scale

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Insect Science 2014年第6期21卷 765-774页

作者： Karine Monceau Olivier Bonnard Jerome moreau Denis Thiery INRA UMR1065 Sante et Agroecologie du Vignoble F-33883 Villenave d'Omon ISVV UMR1065 Sante et Agroecologie du Vignoble Bordeaux Sciences Agro Universite de Bordeaux F-33883 Villenave d'Omon Equipe Ecologie Evolutive UMR 6282 Biogeosciences 6 Bd Gabriel Universite de Bourgogne F-21000 Dijon France

Since its recent introduction into Europe, the yellow-legged hornet, Vespa velutina, has become a major predator of the domestic honeybee, Apis mellifera, but little is known about its hunting behavior. We studied V. velutina hunting behavior by a capture- mark-recapture procedure in an experimental apiary. A total of 360 hornets were captured and tagged, and we determined：（i） the number of hornets visiting the apiary and the changes in time, （ii） the average number of individual visits per half-day and the time elapsed between consecutive recaptures, and （iii） the individual and global distribution of the hornets in the apiary. More than 50% of the marked hornets were recaptured at least once, this increased to 74% in considering the first marked individuals. We estimated 350 hornets visiting the patch daily with at least 1 visit per half-day. The number of marked hornets decreased over time while the number of unmarked ones increased, suggesting a turnover of individuals. The reduction of the delay between consecutive visits indicates that hornets became more efficient over time. Most of the hornets （88%） were recaptured in front of different hives but, overall, the global distribution was aggregative. Hornets were mainly recaptured in front of 1 hive which was neither the smallest nor the biggest colony, suggesting that the major cue used by hornets is not the amount of food. We hypothesize that the defensive behavior of the honeybee colony could explain our results which may be promising to further studies.

关键词： Apis mellifera capture-mark-recapture learning predation Vespidae yellow-legged hornet

Environmental impact improvements due to introducing automation into underground copper mines

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International Journal of Mining Science and Technology 2021年第6期31卷 1159-1167页

作者： Kyle moreau Corey Laamanen Ron Bose Helen Shang John Ashley Scott School of Engineering Laurentian UniversitySudburyON P3E 2C6Canada XPS–glencore Greater SudburyON P0M 1S0Canada

A life-cycle assessment(LCA) model was developed to comparatively analyze the use of manual and automated mining equipment in underground copper mine *** and key variables that were determined to contribute to the environmental impact of operations were identified for six mine sites in a range of geographical locations around the *** model successfully calculated carbon dioxide(CO_(2) eq.) emissions to within 4.9% of the reported annual emissions from the site's respective *** implementation of automation was found to decrease global warming potential by a range of 11.4%-18.0% or 3.9-17.9 kg CO_(2) eq./t *** model was also used to estimate the average reductions across several impact potentials including,acidification(11.9%-17.8%),eutrophication(7.6%-13.7%),and human toxicity(16.0%-20.0%).World-wide the mining industry is moving toward introducing significantly more automation to enhance productivity and *** novel work demonstrates an important third dimension that can support this move,reduced environmental impact.

关键词： Automation Underground copper mines Environmental improvements Life cycle assessment Modelling

Adsorption Behavior of Reducing End-Modified Cellulose Nanocrystals:A Kinetic Study Using Quartz Crystal Microbalance

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Journal of Renewable Materials 2020年第1期8卷 29-43页

作者： Maud Chemin Céline moreau Bernard Cathala Ana Villares INRAE UR BIAF-44316NantesFrance

In this work,we studied the adsorption of modified cellulose nanocrystals onto solid surfaces by quartz crystal microbalance with dissipation monitoring(QCM-D).Cellulose nanocrystals obtained from tunicate(CNC)were modified at reducing end by amidation *** different functionalities were investigated:a polyamine dendrimer(CNC-NH_(2)),which interacts with gold surface by the amine groups;and a biotin moiety(CNC-Biot),which has a strong affinity for the protein streptavidin(SAV).QCM-D results revealed different adsorption behaviors between modified and unmodified ***,unmodified CNCs covered almost all the surface forming a rigid and flat layer whereas reducing end modified CNCs remained rather upright forming a hydrated and viscoelastic layer with lower surface *** analysis of adsorption kinetics allowed the calculation of an apparent collision rate factor,which resulted 10-fold higher for unmodified CNCs compared to reducing end modified CNCs,therefore,demonstrating the different adsorption behavior.

关键词： Cellulose nanocrystals amidation reducing-end modification Voight model collision rate efficiency factor rate constant

How can the forest sector mitigate climate change in a changing climate? Case studies of boreal and northern temperate forests in eastern Canada

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Forest Ecosystems 2022年第2期9卷 267-287页

作者： Lucas moreau Evelyne Thiffault Dominic Cyr Yan Boulanger Robert Beauregard Departement des sciences du bois et de la foret Universite LavalQuebecCanada Science and Technology Branch Environment and Climate Change CanadaGatineauCanada Laurentian Forestry Centre Natural Resources CanadaQuebecCanada

Background:Forest based climate mitigation emerged as a key component of the Paris Agreement,and thus re-quires robust science to reduce uncertainties related to such *** aim of this study was to assess and compare the cumulative effects on carbon dynamics of forest management and climate change on boreal and northern temperate forest sector in eastern Canada for the 2020–2100 ***:We used the spatially explicit forest landscape model LANDIS-II and its extension Forest Carbon Suc-cession,in conjunction with the Carbon Budget Model for Harvested Wood Products *** simulated the dynamics of forest composition and carbon flows from forest ecosystems to wood products and their substitution effect on markets under increasing climate forcing,according to a tonne-year *** were con-ducted for a series of forest management scenarios based on realistic practices principally by clearcut in the boreal territory and continuous-cover forestry in the northern temperate *** scenarios included:i)a business-as-usual scenario(BaU),representing the current management strategy,ii)increased harvesting by 6.3%to 13.9%,iii)increased conservation(*** harvesting by 11.1%to 49.8%),iiii)and a scenario representing the natural evolution of the forest landscape(*** any management activity).Results:Our study revealed that increasing harvesting levels had contrasting effects on the mitigation potential in northern temperate(enhance net sequestration)and boreal forest sector(enhance net emissions)in comparison to the BaU from 2040 onwards,regardless of the future *** storage in wood products and the substi-tution effect were not sufficient to offset carbon emissions from ***,climate change had a strong impact on the capacity of both landscapes to act as carbon *** temperate landscapes became a net source of carbon over time due to their greater vulnerability to climate change than boreal landsc

关键词： Climate change Carbon Forest sector Forest management Boreal landscapes Northern temperate landscape Mitigation potential

Surface Reactivity in Tropical Highly Weathered Soils and Implications for Rational Soil Management

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Pedosphere 2004年第4期14卷 409-423页

作者： R.moreau J.PETARD Research Institute for Development(IRD) 911 Avenue AgropolisBP 6450134394 Montpellier Cedex 5(France).Research Institute for Development(IRD)911 Avenue AgropolisBP 6450134394 Montpellier Cedex 5(France).

Highly weathered soils are distributed in the humid and wet-dry tropics, as well as in the humid subtropics. As a result of strong weathering, these soils are characterized by low activity clays, which develop variable surface charge and related specific properties. Surface reactions regarding base exchange and soil acidification, heavy metal sorption and mobility, and phosphorus sorption and availability of the tropical highly weathered soils are reviewed in this *** controlling surface reactivity towards cations and anions, including ion exchange and specific adsorption processes, are discussed with consideration on practical implications for rational management of these soils. Organic matter content and pH value are major basic factors that should be controlled through appropriate agricultural practices, in order to optimise favorable effects of colloid surface properties on soil fertility and environmental quality.

关键词： heavy metal highly weathered soils phosphorus tropical soil management variable charge minerals

Behavioral syndrome in a native and an invasive hymenoptera species

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Insect Science 2015年第4期22卷 541-548页

作者： Karine Monceau Jerome moreau Juliette Poidatz Olivier Bonnard Denis Thiery INRA UMR 1065 Sante et Agroecologie du Vignoble F-33883 Villenave d'Omon France ISVV UMR 1065 Sante et Agroecologie du Vignoble Bordeaux Sciences Agro Universite de Bordeaux F-33883 Villenave d'Omon France Universite de Bourgogne UMR CNRS 6282 Biogeosciences 6 bd Gabriel 21000 Dijon France

Recent studies have focused on the role of behavior in biological invasions. Individuals may differ consistently in time for several behavioral traits （personality） which covary （behavioral syndrome） resulting in different behavioral types, some of them favoring invasion. Social hymenopterans have a strong potential to be invaders and their success depends primarily on the foundresses＇ ability to found viable colonies. They are expected to be active, explorative and bold for optimally establishing their nest. In Europe, 2 homet species coexist： the native Vespa crabro and the invasive Vespa velutina. These 2 species may compete for nesting sites and we suggest that the initial success of V. velutina has been favored by its behavior in outperforming V. crabro for the traits involved in nest initiation. Here, we （i） defined the personality of V. crabro and V：. velutina, （ii） tested for the existence of behavioral syndrome in these species, and （iii） compared their performances using an open-field test. Our results show that V. crabro foundresses behave consistently but not V. velutina; this lack of consistency being mainly due to reduced variance among individuals. This result questions the possibility of detecting consistent behavioral differences in species having recently undergone a strong bottleneck. Both species exhibit the same correlations between activity, boldness and exploration and V. velutina clearly outperforms 14. crabro for all traits. Our results suggest that activity, boldness, and exploration are implicated in both hornet nest initiation and invasion process which contributed to explain why social hymenopterans are so successful at colonization.

关键词： animal personality biological invasion invasion syndrome Vespa crabro Vespa velutina Vespidae