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Catalytic synthesis of acetals and ketals with H3PW12O40/PAn

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Rare Metals 2008年第1期27卷 89-94页

作者： YANG Shuijin ZHANG Yijun DU Xinxian philippe G. Merle Hubei Key Laboratory of Bioanalytical Technique Department of Chemistry and Environmental Engineering Hubei Normal University Huangshi 435002 China Department of Chemistry and Biochemistry Concordia University Montreal H4B 1R6 Canada

A new environmental friendly catalyst H3PW12O40/PAn was prepared and identified by means of FT-IR,XRD,and TG/*** optimum conditions have been found;that is,the mass ratio of PAn to H3PW12O40 is 1：1.5,the volume of methanol is 20 mL,and the reflux reaction time is 3 *** structural identity of Keggin units is preserved after the incorporation into polyaniline *** activities of H3PW12O40/PAn in synthesizing 2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane,2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane,cyclohexanone ethylene ketal,cyclohexanone 1,2-propanediol ketal,butanone ethylene ketal,butanone 1,2-propanediol ketal,2-phenyl-1,3-dioxolane,4-methyl-2-phenyl-1,3-dioxolane,2-propyl-1,3-dioxolane,and 4-methyl-2-propyl-1,3-dioxolane were *** has been demon-strated that H3PW12O40/PAn is an excellent *** factors concerned in these reactions were *** optimum conditions are as follows：the molar ratio of aldehyde/ketone to glycol（r） is 1：1.5,the mass ratio of the catalyst used to the reactants is 0.6%,and the reaction time is 1.0 *** these conditions,the yield is as follows：2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane,69.0%;2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane,79.5%;cyclohexanone ethylene ketal,78.9%;cyclohexanone 1,2-propanediol ketal,85.3%;butanone ethylene ketal,56.9%;butanone 1,2-propanediol ketal,78.1%;2-phenyl-1,3-dioxolane,76.3%;4-methyl-2-phenyl-1,3-dioxolane,94.2%;2-propyl-1,3-dioxolane,70.7%;and 4-methyl-2-propyl-1,3-dioxolane,79.2%.

关键词： phosphotungstic acid acetal ketal polyaniline catalysis

Comparison and analysis of the efficacy of drug therapy for liver cancer

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Hepatoma Research 2020年第9期6卷 55-64页

作者： philippe Merle Miroslava Subic Unitéd’Hépatologie et Gastroentérologie Hôpital de la Croix RousseHospices Civils de LyonLyon 69004France. Centre de Recherche en Cancérologie de Lyon INSERM U1052Lyon 69003France. UniversitéClaude Bernard Lyon 1 Villeurbanne 69100France

Hepatocellular carcinoma(HCC)is a poor prognosis tumor when not accessible to potentially curative treatments such as surgical resection,thermal ablations or liver *** cytotoxic chemotherapies have shown inconsistent clinical *** 2007,sorafenib,a tyrosine kinase inhibitor(TKI),was the first systemic therapy able to significantly improve the outcome of HCC patients non-eligible for curative or loco-regional therapies,despite a modest tolerance and low tumor objective response rate(ORR).Among the newer TKIs approved after 2017,lenvatinib was the first to show a striking ORR and demonstrate non-inferiority *** in the first-line ***,phase 3 trials showed the benefit of other TKIs,regorafenib and cabozantinib,and the anti-angiogenic ramucirumab monoclonal antibody,in systemic second-line *** checkpoint inhibitors targeting PD1,achieved striking tumor shrinkage in some patients in monotherapy,seeming to be associated with exciting ***,this occurred in too few patients to improve the median overall *** recently,the combination of anti-angiogenic drugs targeting the liver microenvironment with PD-1/PD-L1 inhibitors,such as the combination of bevacizumab and atezolizumab,proved to be substantially effective in phase 3,and other combinations of PD-1/PD-L1 and CTLA-4 inhibitors or TKIs have raised a lot of hopes for the systemic treatment of HCC.

关键词： Hepatocellular carcinoma therapy immune checkpoint inhibitors tyrosine kinase inhibitors

Recent Advances on Graphene Quantum Dots for Electrochemical Energy Storage Devices

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Energy & Environmental Materials 2022年第1期5卷 201-214页

作者： Noura Zahir Pierre Magri Wen Luo Jean Jacques Gaumet philippe Pierrat CNRS L2CM UMR 7053 Universit e de Lorraine LCP-A2MC EA4632 Institut Jean Barriol Universit e de Lorraine State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technologywuhan 430070china

Graphene quantum dots(GQDs)which are nanofragments of graphene with an average size between 2 and 50 nm have attracted much attention due to their outstanding properties such as high conductivity,high surface area,and good solubility in various *** combine the quantum confinement and edges effects and the properties of ***,GQDs offers a broad range of applications in various fields(medicine,energy conversion,and energy storage devices).This review will present the recent research based on the introduction of GQDs in batteries,supercapacitors,and microsupercapacitors as electrodes materials or mixed with an active material as an auxiliary ***,discussed on selected examples,summarize the electrochemical performances and finally,challenges and perspectives are recalled for the subsequent optimization strategy of electrode *** review is expected to appeal a broad interest on functional GQDs materials and promote the further development of high-performance energy storage device.

关键词： energy storage graphene quantum dots lithium ion batteries sodium ion batteries supercapacitor

The Bafoussam volcanic series:origin and evolution of the volcanism along the Cameroon volcanic line

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Acta Geochimica 2022年第6期41卷 1049-1068页

作者： philippe Essomba Gilles Chazot Nicaise Blaise Tchuimegnie Ngongang Arnaud Agranier Pierre Kamgang HervéBellon philippe Nonnotte Pierre Wotchoko Innocent Badriyo Département Des Sciences de La Terre FacultéDes SciencesUniversitéde YaoundéIB.P.812YaoundéCameroun Geo-Ocean CNRSIfremerUMR6538Univ Brest29280PlouzaneFrance Département Des Sciences de La Terre FacultéDes SciencesUniversitéde DoualaDoualaCameroun Department of Geology Higher Teacher Training CollegeUniversity of BamendaBambiliBamendaCameroon Département de Séismologie et Géologie Observatoire Volcanologique de Goma-RDCGomaRépublique Démocratique du Congo

The Bafoussam area in western Cameroon is part of the central Cameroon Volcanic Ligne(CVL).This study presents the mineralogy,major and trace element compositions,Sr-Pb-Hf isotopes,and new K-Ar geochronological data about mafic and felsic volcanic *** rocks belong to two different series:A transitional series made of basalts,basaltic andesite,and trachytes and an alkaline mafic series with basalts,hawaiites,and *** age data show that the transitional series belongs to the oldest part of the CVL and was emplaced between 47 and 35 *** alkaline volcanism is younger,with ages ranging from10 to 4.5 *** evolution in both series is accomplished through a fractional crystallization process,with the removal of olivine and clinopyroxene,while plagioclase does not seem to be a major crystallizing *** the samples are enriched in incompatible trace elements,but the rocks from the alkaline series have more fractionated REE patterns and high Nb content compared to the transitional mafic *** lavas have lower initial^(87)Sr/^(86)Sr and higher^(176)Hf/^(177)Hf and Pb isotopic ratios than the transitional *** La/Nb and high^(87)Sr/^(86)Sriratio are among chemical characteristics that show that some samples from the transitional series have interacted with a crustal component during their evolution in the *** cannot be used for discussing the mantle source of the volcanic rocks from this *** elements show that primary magmas for both series formed in a garnet-bearing mantle source,with higher partial melting degrees(3-5%)for the transitional magmas than for the alkaline magmas(<2.5%).Combining trace elements and isotopic ratios,we show that the Bafoussam lavas formed from two different mantle *** magmas formed from a pyroxenite-bearing enriched mantle with low Pb isotopic *** mantle source is present in all the oldest lavas from the *** magmas formed from an HIMU-like mantle sourc

关键词： Cameroon Volcanic Line Bafoussam Mafic volcanic rocks Felsic volcanic rocks Mantle source

Hepatitis B and human immunodeficiency virus co-infection

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World Journal of Gastroenterology 2014年第46期20卷 17360-17367页

作者： Bao-Chau Phung philippe Sogni Odile Launay Université Paris Descartes Sorbonne Paris Cité75006 ParisFrance Assistance Publique-H?pitaux de Paris H?pital CochinCIC Cochin Pasteur75014 ParisFrance Inserm CIC141775014 ParisFrance APHP H?pital CochinService d’hépatologie75014 ParisFrance

Hepatitis B and human immunodeficiency virus(HBV and HIV)infection share transmission patterns and risk factors,which explains high prevalence of chronic HBV infection in HIV infected *** natural course of HBV disease is altered by the HIV infection with less chance to clear acute HBV infection,faster progression to cirrhosis and higher risk of liver-related death in HIVHBV co-infected patients than in HBV mono-infected *** infected patients with chronic hepatitis B should be counseled for liver damage and surveillance of chronic hepatitis B should be performed to screen early hepatocellular *** tools are now available to evaluate liver *** hepatitis B core antibodies(anti-HBc)are a good predictive marker of occult HBV *** the prevalence and significance of occult HBV infection is controversial,but its screening may be important in the management of antiretroviral *** against HBV infection is recommended in non-immune HIV *** optimal treatment for almost all HIV-HBV co-infectedpatients should contain tenofovir plus lamivudine or emtricitabine and treatment should not be stopped to avoid HBV *** term tenofovir therapy may lead to significant decline in hepatitis B surface *** emergence of resistant HBV strains may compromise the HBV therapy and vaccine therapy.

关键词： Chronic hepatitis B Human immunodeficiency virus Management Occult hepatitis Treatment

Scale-Free Percolation in Continuum Space

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Communications in Mathematics and Statistics 2019年第3期7卷 269-308页

作者： philippe Deprez Mario V.Wüthrich RiskLab Department of MathematicsETH Zurich8092 ZurichSwitzerland

The study of real-life network modeling has become very popular in recent *** attractive model is the scale-free percolation model on the lattice Zd,d≥1,because it fulfills several stylized facts observed in large real-life *** adopt this model to continuum space which leads to a heterogeneous random-connection model on Rd:Particles are generated by a homogeneous marked Poisson point process on Rd,and the probability of an edge between two particles is determined by their marks and their *** this model we study several properties such as the degree distributions,percolation properties and graph distances.

关键词： Scale-free percolation Continuum percolation Random-connection model Degree distribution Phase transition Graph distance

Climate change in the Tianshan and northern Kunlun Mountains based on GCM simulation ensemble with Bayesian model averaging

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Journal of Arid Land 2017年第4期9卷 622-634页

作者： YANG Jing FANG Gonghuan CHEN Yaning philippe DE-MAEYER State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China National Institute of Water and Atmospheric Research Christchurch 8011New Zealand Department of Geography Ghent UniversityGhent 9000Belgium Sino-Belgian Joint Laboratory for Geo-Information Urumqi 830011China

Climate change in mountainous regions has significant impacts on hydrological and ecological systems. This research studied the future temperature, precipitation and snowfall in the 21^（st） century for the Tianshan and northern Kunlun Mountains（TKM） based on the general circulation model（GCM） simulation ensemble from the coupled model intercomparison project phase 5（CMIP5） under the representative concentration pathway（RCP） lower emission scenario RCP4.5 and higher emission scenario RCP8.5 using the Bayesian model averaging（BMA） technique. Results show that（1） BMA significantly outperformed the simple ensemble analysis and BMA mean matches all the three observed climate variables;（2） at the end of the 21^（st） century（2070–2099） under RCP8.5, compared to the control period（1976–2005）, annual mean temperature and mean annual precipitation will rise considerably by 4.8°C and 5.2%, respectively, while mean annual snowfall will dramatically decrease by 26.5%;（3） precipitation will increase in the northern Tianshan region while decrease in the Amu Darya Basin. Snowfall will significantly decrease in the western TKM. Mean annual snowfall fraction will also decrease from 0.56 of 1976–2005 to 0.42 of 2070–2099 under RCP8.5; and（4） snowfall shows a high sensitivity to temperature in autumn and spring while a low sensitivity in winter, with the highest sensitivity values occurring at the edge areas of TKM. The projections mean that flood risk will increase and solid water storage will decrease.

关键词： climate change GCM ensemble Bayesian model averaging Tianshan and northern Kunlun Mountains

One-Pot Microwave-Assisted Synthesis of Graphene/Layered Double Hydroxide(LDH) Nanohybrids

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Nano-Micro Letters 2015年第4期7卷 332-340页

作者： Sunil P.Lonkar Jean-Marie Raquez philippe Dubois Laboratory of Polymeric and Composite Materials Center of Innovation and Research in Materials and PolymersUniversity of Mons Department of Chemical Engineering The Petroleum Institute

A facile and rapid method to synthesize graphene/layered double hydroxide(LDH)nanohybrids by a microwave technique is *** synthesis procedure involves hydrothermal crystallization of Zn–Al LDH at the same time in situ reduction of graphene oxide(GO)to *** microstructure,composition,and morphology of the resulting graphene/LDH nanohybrids were *** results confirmed the formation of nanohybrids and the reduction of graphene *** growth mechanism of LDH and in situ reduction of GO were *** LDH sheet growth was found to prevent the scrolling of graphene layers in resulting *** electrochemical properties exhibit superior performance for graphene/Zn–Al LDH hybrids over pristine *** present approach may open a strategy in hybridizing graphene with multimetallic nano-oxides and hydroxides using microwave method.

关键词： Graphene LDHs Nanostructures Microwave Composite materials

On the relevance of analytical film thickness EHD equations for isothermal point contacts: Qualitative or quantitative predictions?

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Friction 2016年第4期4卷 369-379页

作者： Jean-David WHEELER philippe VERGNE Nicolas FILLOT David PHILIPPON Univ Lyon INSA Lyon CNRS LaMCoS-UMR5259 Villeurbanne F-69621 France

Thin film and elastohydrodynamic lubrication regimes are rather young domains of tribology and they are still facing unresolved *** they rely upon a full separation of the moving surfaces by a thin (or very thin) fluid film,the knowledge of its thickness is of paramount importance,as for instance to developing lubricated mechanisms with long lasting and efficient *** a consequence,a large collection of formulae for point contacts have been proposed in the last 40 ***,their accuracy and validity have rarely been *** purpose of this paper is to offer an evaluation of the most widespread analytical formulae and to define whether they can be used as qualitative or quantitative *** methodology is based on comparisons with a numerical model for two configurations,circular and elliptical,considering both central and minimum film thicknesses.

关键词： thin film lubrication elastohydrodynamic lubrication (EHL) film thickness prediction EHD analytical equation central film thickness minimum film thickness circular contacts elliptical contacts