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Carleman Estimates for Parabolic Equations with Nonhomogeneous Boundary Conditions

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Chinese Annals of Mathematics,Series B 2009年第4期30卷 333-378页

作者： Oleg Yu IMANUVILOV Jean Pierre PUEL Masahiro YAMAMOTO department of Mathematics Colorado State University 101 Weber Building Fort Collins CO 80523USA laboratoire de mathematiques de versailles Universit de Versailles-St. Quentin 45 Avenue des Etats Unis 78035 Versailles France. department of Mathematical Sciences University of Tokyo Komaba Meguro Tokyo 153 Japan.

The authors prove a new Carleman estimate for general linear second order parabolic equation with nonhomogeneous boundary conditions. On the basis of this estimate, improved Carleman estimates for the Stokes system and for a system of parabolic equations with a penalty term are obtained. This system can be viewed as an approximation of the Stokes system.

关键词： Controllability Parabolic equations Carleman estimates

On Lagrange-Projection Schemes for Shallow Water Flows Over Movable Bottom with Suspended and Bedload Transport

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Numerical Mathematics(Theory,Methods and Applications) 2023年第4期16卷 1087-1126页

作者： Alessia del Grosso Manuel J.Castro Díaz Christophe Chalons Tomás Morales de Luna UniversitéParis-Saclay UVSQCNRSLaboratoire de Mathématiques de Versailles78000VersaillesFrance Dpto.de Análisis Matemático Facultad de CienciasUniversidad de MálagaCampus de Teatinos S/N29081 MálagaSpain

In the present work we aim to simulate shallow water flows over movable bottom with suspended and bedload *** order to numerically approximate such a system,we proceed step by *** start by considering shallow water equations with non-constant density of the mixture ***,the Exner equation is included to take into account bedload sediment ***,source terms for friction,erosion and deposition processes are ***,observe that the sediment particle could go in suspension into the water or being deposited on the *** the numerical scheme,we rely on well-balanced Lagrange-projection *** particular,since sediment transport is generally a slow process,we aim to develop semi-implicit schemes in order to obtain fast *** Lagrange-projection splitting is well-suited for such a purpose as it entails a decomposition of the(fast)acoustic waves and the(slow)material waves of the ***,in subsonic regimes,an implicit approximation of the acoustic equations allows us to neglect the corresponding CFL condition and to obtain fast numerical schemes with large time step.

关键词： Shallow water flows movable bottom erosion-deposition processes Lagrangeprojection schemes implicit-explicit schemes

Oxidation of propane over substituted Keggin phosphomolybdate salts

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Journal of Natural Gas Chemistry 2009年第3期18卷 319-324页

作者： T.Mazari C.Roch.Marchal S.Hocine N.Salhi C.Rabia laboratoire de Chimie du Gaz Naturel Faculté de ChimieUniversité des Sciences et de la Technologie Houari Boumediéne ILV-UMR 8180 CNRS-Université de versailles-St Quentin-en-Yvelines Batiment Lavoisier45 avenue des Etats-Unis78035 Versailles CedexFrance

Ammonium salts, （NH4）6HPMo11MO40 （M = Ni, Co, Fe）, have been investigated for the oxidation of propane, with molecular oxygen, at temperature ranging between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9 ℃/min. They were characterized by BET method, XRD, 31p NMR, UV-Vis and IR techniques. The catalysts were found active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9 ℃/min.

关键词： propane oxidation propene acrolein polyoxometalates phosphomolybdate

Oxidation of propane over ammonium-transition metal mixed keggin phosphomolybdate salts

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Journal of Natural Gas Chemistry 2010年第1期19卷 54-60页

作者： T. Mazari C. Roch. Marchal S. Hocine N. Salhi C. Rabia laboratoire de Chimie du Gaz Naturel Faculte' de Chimie Universite' des Sciences et de la Technologie Houari Boumedie`ne USTHB BP32 El-Alia Bab-Ezzouar Alger Alge'rie ILV-UMR 8180 CNRS Universite' de Versailles -St Quentin-en-Yvelines Ba?timent Lavoisier 45 avenue des Etats-Unis 78035 Versailles Cedex France

Mixed ammonium-transition metal salts with formula of （NH4）xMyHzPMo12O40 （M = Ni^2＋, Co^2＋ or Fe ^3＋） denoted as MPMo12 have been investigated for the oxidation of propane, with molecular oxygen, at temperature range between 380 ℃ and 420 ℃ after in-situ pre-treatment performed at two heating rate of 5 or 9℃/min. They were characterized by BET method, XRD, UV-Vis and IR techniques. The catalysts were found to be active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9℃/min. FePMo12 was found to be a more active catalyst for propene （17.2% yield） with minimal over deep oxidation （0.3% yield in COx）.

关键词： phosphomolybdate ammonium keggin propane oxidation propene acrolein

Induced structural modifications in ZnS nanowires via physical state of catalyst:Highlights of 15R crystal phase

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Nano Research 2022年第1期15卷 377-385页

作者： Sumit Kumar Frederic Fossard Gaelle Amiri Jean-Michel Chauveau Vincent Sallet Groupe d'Etude de la Matiere Condensee(GEMAC) Universite Paris-SaclayCNRS-Universite de Versailles St Quentin en Yvelines45 avenue des Etats-UnisVersailles 78035France laboratoire d'Etude des Microstructures(LEM) CNRS-ONERAUniversite Paris-Saclay29 avenue Division LeclercChatillon 92322France

Peculiar and unique growth mechanisms involved in semiconductor nanowires(NWs)pave the way to the achievement of new crystallographic phases and remarkable material properties,and hence,studying polytypism in semiconductor NWs arouses a strong interest for the next generation of electronic and photonic *** this context,the growth of ZnS nanowires has been investigated,as bulk ZnS compound exhibits numerous unstable polytypes at high temperatures,but their stable occurrence is highly anticipated in a nanowire due to its special quasi-dimensional shape and growth *** this work,the idea is to provide a change in the growth mechanism via the physical state of catalyst droplet(liquid or solid)and hence,study the induced structural modifications in ZnS *** HRTEM images of VLS(via liquid alloyed catalyst)grown ZnS NWs show periodic stacking faults,which is precisely identified as a stacking sequence of cubic or hexagonal individual planes leading to an astonishing 15R crystal *** crystallographic phase is observed for the first time in ***,NWs grown with VSS(via solid catalyst)show crystal polytypes of zinc blende and *** calculate and discuss the role of cohesive energies in the formation of such ZnS ***,we present the selection rules for the crystallization of such 15R structure in NWs and discuss the involved VLS and VSS growth mechanisms leading to the formation of different crystal phases.

关键词： ll-VI semiconductors MOCVD vapor-liquid-solid(VLS) vapor-solid-solid(VSS) TEM analysis polytypism

Analysis of Natural Allelic Variation Controlling Arabidopsis thaliana Seed Germinability in Response to Cold and Dark： Identification of Three Major Quantitative Trait Loci

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Molecular Plant 2008年第1期1卷 145-154页

作者： Ping-Hong Meng Audrey Macquet Olivier Loudet Annie Marion-Poll Helen M. North laboratoire de Biologie des Semences UMR 204 INRA AgroParisTech Institut Jean-Pierre Bourgin F-78026 Versailles Cedex France Station de Genetique et Amelioration des Plantes INRA Institut Jean-Pierre Bourgin F-78026 Versailles Cedex France Present address: Institute of Horticulture Guizhou Academy of Agricultural Sciences GuiYang Guizhou Province 550006 RR. China

Light and temperature are key external factors in the control of Arabidopsis thaliana seed germination and dormancy mechanisms. Perception and response to these stimuli have to ensure that seedling emergence and growth occur at the most advantageous time for correct establishment. Analysis of over 300 Arabidopsis accessions identified 14, from 12 different geographical locations, that were able to germinate to greater than 20% at 6℃ in the dark. This natural variation was exploited to identify genetic loci responsible for cold-tolerant, dark germination. A quantitative trait loci approach was used on recombinant inbred line progeny of a cross between Bay-0 and Shahdara. Six distinct quantitative trait loci were identified, three of which were major loci, each responsible for 17-25% of the phenotypic variability in this trait. Parental phenotypes indicated that the majority of the cold-tolerant, dark-germination characteristics are related to light responses. Validation of the three major loci using heterogeneous inbred families confirmed the feasibility of fine mapping and cloning the genes at the quantitative trait loci responsible for cold-tolerant, dark germination.

关键词： .Arabidopsis accessions Seed Germinability Cold and Dark Shahdara

Local and teleconnected temperature effects of afforestation and vegetation greening in China

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National Science Review 2020年第5期7卷 897-912页

作者： Yue Li Shilong Piao Anping Chen Philippe Ciais Laurent Z.X.Li Sino-French Institute for Earth System Science College of Urban and Environmental Sciences Peking University Key Laboratory of Alpine Ecology and Biodiversity Institute of Tibetan Plateau Research Chinese Academy of Sciences Center for Excellence in Tibetan Earth Science Chinese Academy of Sciences department of Biology Colorado State University laboratoire des Sciences du Climat et de l'Environnement/Institut Pierre Simon Laplace Commissariata l Energie Atomique et aux Energies Alternatives–CNRS–Universite de Versailles Saint-QuentinUniversite Paris-Saclay laboratoire de Met eorologie Dynamique Centre National de la Recherche ScientifiqueSorbonne UniversiteEcole Normale Superieure Ecole Polytechnique

Afforestation in China provides carbon sequestration and prevents soil erosion, but its remote impacts on climate in other regions via the coupling of forest energy fluxes with atmospheric circulation are largely unknown. Here, we prescribe inventory-based forest cover change and satellite-observed leaf area index from 1982 to 2011 in a coupled land-atmosphere model to simulate their biophysical climate effects. Both local and global surface air temperatures show a seasonal contrast in response to past vegetation cover expansion over China:a phenomenon we primarily attribute to a variation of seasonality of vegetation greening. A large cooling in spring results in concurrent decreases in geopotential height over China and zonal wind over Mongolia, causing a dipole structure in the upper troposphere over the Arctic. This accounts for～58%of simulated spring warming over the Russian Arctic and～61% of simulated spring cooling over the Canadian Artic. Our results imply that spring vegetation dynamics in China may affect climate in northern high latitudes.

关键词： afforestation vegetation greening China biophysical climate effect coupled land-atmosphere model

Observations of contrasted glacial-interglacial dissolution of foraminifera above the lysocline in the Bay of Bengal,northeastern Indian Ocean

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Acta Oceanologica Sinica 2021年第1期40卷 155-161页

作者： Duo Wang Xuan Ding Franck Bassinot School of Ocean Sciences China University of Geosciences(Beijing)Beijing 100083China laboratoire des Sciences du Climat et de l’Environnement National Agency for Nuclear Energy/National Centre for Scientifique Research/University of Versailles-Saint QuentinGif-sur-Yvette 91198France

Site U1446(19°50’N,85°44’E,at water depth 1430 m)was drilled during Expedition 353(Indian monsoon rainfall)of the International Ocean Discovery Program(IODP).It is located in the Mahanadi offshore basin,on the northern Bay of *** rates and contents of biocarbonates are high at this relatively shallow *** a micropaleontological approach,we examined planktonic and benthic foraminifera in the upper around 40 m of this site,spanning the last around 190 ka.A striking feature of the foraminiferal record is the occurrence of strong but varying dissolution although the site is located well above the modern *** strong dissolution has never been reported in this *** estimated the flux of foraminifera and quantified the ratio of benthic foraminifera over total foraminifera(benthic/total foraminifera)along with the foraminifer fragmentation index in order to characterize past changes in this above-lysocline *** study reveals a clear glacialinterglacial contrast,with a stronger dissolution during marine isotope stages(MISs)1 and 5 than during MISs 2–4 and *** a difference in preservation is likely to have a strong impact on geochemical proxies measured on *** new observations call for an in-depth study of the causes of such above-lysocline dissolution in the region,and an evaluation of its impact on the foraminifera-based proxies used for paleoenvironmental reconstruction.

关键词： foraminifera dissolution lysocline glacial-interglacial Bay of Bengal

New Strigolactone Analogs as Plant Hormones with Low Activities in the Rhizosphere

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Molecular Plant 2014年第4期7卷 675-690页

作者： Francois-Didier Boyer Alexandre de Saint Germain Jean-Bernard Pouvreau Guillaume Clave Jean-Paul Pillot Amelie Roux Amanda Rasmussen Stephen depuydt Dominique Lauresserguesh Nicolas Frei dit Frey Thomas S.A. Heugebaert Christian V. Stevens Danny Geelen Sofie Goormachtig Catherine Rameau Institut Jean-Pierre Bourgin UMR1318 Institut National de la Recherche Agronomique (INRA)-AgroParisTech Route de Saint-Cyr (RD 10) F-78026 Versailles Cedex France Centre de Recherche de Gif Institut de Chimie des Substances Naturelles UPR2301 Centre National de la Recherche Scientifique (CNRS) 1 avenue de la Terrasse F-91198 Gif-sur-Yvette Cedex France laboratoire de Biologie et de Pathologie Vegetales EA 1157 SFR 4207 QUASAV Universite de Nantes 44322 Nantes France Plant Production Faculty of Bioscience Engineering Ghent University Coupure links 653 Ghent 9000 Belgium Present address: School of Biosciences Division of Plant and Crop Production The University of Nottingham Sutton Bonington Leicestershire LE12 5RD UK department of Plant Systems Biology VIB Ghent 9052 Belgium department of Plant Biotechnology and Bioinformatics Ghent University Ghent 9052 Belgium laboratoire de Recherche en Sciences Vegetales UMR 5546 Universite de Toulouse- Centre National de la Recherche Scientifique (CNRS) BP 42617 Auzeville F-31326 Castanet-Tolosan France Research Group SynBioC Department of Sustainable Organic Chemistry and Technology Faculty of Bioscience Engineering Ghent University Coupure links 653 B-9000 Gent Belgium

Strigolactones （SLs） are known not only as plant hormones, but also as rhizosphere signals for establishing symbiotic and parasitic interactions. The design of new specific SL analogs is a challenging goal in understanding the basic plant biology and is also useful to control plant architectures without favoring the development of parasitic plants. Two different molecules （23 （3＇-methyI-GR24）, 31 （thia-3＇-methyl-debranone-like molecule）） already described, and a new one （AR36）, for which the synthesis is presented, are biologically compared with the well-known GR24 and the recently identified CISA-1. These different structures emphasize the wide range of parts attached to the D-ring for the bioactivity as a plant hormone. These new compounds possess a common dimethylbutenolide motif but their structure varies in the ABC part of the molecules： 23 has the same ABC part as GR24, while 31 and AR36 carry, respectively, an aromatic ring and an acyclic carbon chain. detailed information is given for the bioactivity of such derivatives in strigolactone synthesis or in perception mutant plants （pea rmsl and rms4, Arabidopsis max2 and, max4） for different hormonal functions along with their action in the rhizosphere on arbuscular mycorrhizal hyphal growth and parasitic weed germination.

关键词： strigolactones synthetic analogs Pisum sativum Arabidopsis root parasitic plants Gigaspora rosea plant growth regulator.