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Structural studies of BaTiO_3:Er^(3+) and BaTiO_3:Yb^(3+) powders synthesized by hydrothermal method

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Journal of Rare Earths 2014年第11期32卷 1016-1021页

作者： Garrido-Hernández A García-Murillo A Carrillo-Romo F de J Cruz-Santiago L A Chadeyron G Morales-Ramírez A de J Velumani S T.A. Post-graduate Student. instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F México instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F departament of Engineering Materials Tecnológico de Estudios Superiores de Coacalco (TESCo) Av. 16 de Septiembre # 54 Cabecera Municipal C.P. 55700 Coacalco de Berriozábal Estado de México institut de chimie de Clermont-Ferrand UMR 6296 CNRS / UBP / ENSCCF 24 avenue des Landais BP 80026 63171 Aubière Cedex – France department of Electrical Engineering (SEES) Centro de Investigación y de Estudios Avanzados del IPN Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico D.F. Mexico

Erbium and ytterbium doped barium titanate nanopowders were prepared using the hydrothermal method. A barium titanate structure doped with rare earth ions manifested new characteristics and improved the field of application of optical devices such as trichromatic tubes, LCD displays, lamps, and infrared lasers. In this work, BaTiO3：Er3＋ and BaTiO3：Yb3＋ were prepared using barium chloride [BaCl2], titanium butoxide [C16H36O4Ti], erbium chloride [ErCl3] and ytterbium chloride [YbCl3] as precursors. Anhydrous methanol was employed as a solvent. Metallic potassium was used to promote solubility in the system and increase the pH to 13. This method yielded the formation of a predominantly cubic structure in both Er3＋ and Yb3＋ doped BaTiO3 powders. Characteristic bondings of BaTiO3 were observed with FT-IR spectroscopy. The predominantly cubic structure was confirmed by X-ray diffraction and micro-Raman analyses. The particle size（～30 nm） was estimated using the Scherrer equation and X-ray diffraction data. The results were presented and discussed.

关键词： nanopowders hydrothermal BaTiO3:Er3+ BaTiO3:Yb3+ rare earths

Artificial neural network approach for multiphase segmentation of battery electrode nano-CT images

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npj Computational Materials 2022年第1期8卷 255-265页

作者： Zeliang Su Etienne decencière Tuan-Tu Nguyen Kaoutar El-Amiry Vincent de Andrade Alejandro A.Franco Arnaud demortière Laboratoire de Réactivitéet chimie des Solides(LRCS) CNRS UMR 7314Universitéde Picardie Jules VerneHub de l’EnergieRue Baudelocque80039Amiens CedexFrance Réseau sur le Stockage Electrochimique de l’Energie(RS2E) CNRS FR 3459Hub de l’EnergieRue Baudelocque80039Amiens CedexFrance MINES ParisTech–PSL Research University CMMCenter for Mathematical Morphology35 rue Saint HonoréFontainebleauFrance Renault Technocentre 78084GuyancourtFrance Advanced Photon Source Argonne National LaboratoryLemontUSA institut Universitaire de France 101 Boulevard Saint Michel75005ParisFrance ALISTORE-European Research institute CNRS FR 3104Hub de l’EnergieRue Baudelocque80039Amiens CedexFrance

The segmentation of tomographic images of the battery electrode is a crucial processing step,which will have an additional impact on the results of material characterization and electrochemical ***,manually labeling X-ray CT images(XCT)is time-consuming,and these XCT images are generally difficult to segment with histographical *** propose a deep learning approach with an asymmetrical depth encode-decoder convolutional neural network(CNN)for real-world battery material *** network achieves high accuracy while requiring small amounts of labeled data and predicts a volume of billions voxel within few *** applying supervised machine learning for segmenting real-world data,the ground truth is often *** results of segmentation are usually qualitatively justified by visual *** try to unravel this fuzzy definition of segmentation quality by identifying the uncertainty due to the human bias diluted in the training *** CNN trainings using synthetic data show quantitative impact of such uncertainty on the determination of material’s ***-XCT datasets of various battery materials have been successfully segmented by training this neural network from *** will also show that applying the transfer learning,which consists of reusing a well-trained network,can improve the accuracy of a similar dataset.

关键词： neural network battery

Synthesis of two mono-deoxy β-cyclodextrin derivatives as useful tools for confirming DIBAL-H promoted bis-de-O-methylation mechanism

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Chinese Chemical Letters 2012年第12期23卷 1315-1318页

作者： Su Long Xiao de Min Zhou Ming Yang Fei Yu Li He Zhang Pierre Sinay Yong Min Zhang State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking University institut parisien de chimie moleculaire UMR CNRS 7201Universite Pierre et Marie Curie-Paris 64 Place Jussieu institute for Interdisciplinary Research Jianghan UniversityWuhan Economic and Technological Development Zone

Diisobutylaluminium hydride （DIBAL-H） promotes secondary rim regioselective bis-de-O-methylation of permethylated β- cyclodextrin （β-CD） to give diol 2. To gain an insight into the mechanism of this remarkable regioselective behavior, two corresponding permethylated β-CDs with an alcohol function at either 2- or 3-position were synthesized in our previous study. As a step further to this work, the two compounds were subjected to deoxygenation reaction with tributyltin hydride in the present of 2,2＇- azobisisobutyronitrile affording the corresponding 2- and 3-deoxy permethylated β-CD derivatives （19 and 16）. The structures of these two compounds were characterized by 1D and 2D NMR and HRMS. Compounds 16 and 19 were unable to react with DIBAL- H which suggests that O-2A and O-3B are necessary for DIBAL-H promoted bis-de-O-methylation reaction of permethylated β-CD.

关键词： Cyclodextrin (CD) DIBAL-H deoxy Synthesis Mechanism

SURVEY OF PLANTS USED IN TRADITIONAL MEDICINE AGAINST MALARIA IN BUKAVU AND UVIRA/DR CONGO

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World Journal of Traditional Chinese Medicine 2015年第4期1卷 98-98页

作者： Henry Manya Mboni Valentin Bashige Chiribagula Salvius Bakari Amuri dede Mbangu Munahu Joseph Kahumba Byanga Caroline Stévigny Jean-Baptiste Lumbu Simbi Pierre Duez Laboratoire de Pharmacognosie Faculté des Sciences Pharmaceutiques Université de Lubumbashi (UNILU) Laboratoire de Pharmacognosie Bromatologie et Nutrition humaine Université Libre de Bruxelles (ULB) Service de chimie Organique Département de Chimie Faculté des Sciences/UNILU institut National pour l'Etude et la Recherche Agronomique Station de Kipopo Laboratory of Therapeutic Chemistry & Pharmacognosy University of Mons (UMONS)

Malaria,for its high prevalence and morbidity,is one of the major tropical parasitic diseases,particularly in DR *** therapy not only uses modem antimalarials,for which many Resistance problems are encountered,but als... 详细信息

关键词： SURVEY OF PLANTS USED IN TRADITIONAL MEDICINE AGAINST MALARIA IN BUKAVU AND UVIRA/DR CONGO DR

Synthesis and Biological Evaluation of a Highly Constrained Analogue of Methylthioadenosine (MTA)

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International Journal of Organic Chemistry 2012年第4期2卷 398-403页

作者： Gustavo Senra G. de Carvalho Rafael Mafra de P. Dias Jean-Louis Fourrey Vania L. Silva Cláudio G. Diniz Adilson D. da Silva departamento de Parasitologia Microbiologia e Imunologia Instituto de Ciências Biológicas (ICB) Universidade Federal de Juiz de Fora Juiz de Fora-MG Brasil departamento de Química Instituto de Ciências Exatas (ICE) Universidade Federal de Juiz de Fora Juiz de Fora-MG Brasil institut de chimie des Substances Naturelles Gif-sur-Yvette Cedex France

We describe the synthesis and the antibacterial evaluation 2’,N3-cyclonucleoside 3 analogue of MTA that is characterized by the presence of an additional linkage between the heterocyclic ring and the sugar moiety.

关键词： Synthesis Biological Evaluation Antibacterial Analogue Methylthioadenosine

A Phelipanche ramosa KAI2 protein perceives strigolactones and isothiocyanates enzymatically

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Plant Communications 2021年第5期2卷 132-147页

作者： Alexandre de Saint Germain Anse Jacobs Guillaume Brun Jean-Bernard Pouvreau Lukas Braem David Cornu Guillaume Clavé Emmanuelle Baudu Vincent Steinmetz Vincent Servajean Susann Wicke Kris Gevaert Philippe Simier Sofie Goormachtig Philippe delavault François-Didier Boyer institut Jean-Pierre Bourgin INRAEAgroParisTechUniversitéParis-Saclay78000 VersaillesFrance department of Plant Biotechnology and Bioinformatics Ghent University9052 GentBelgium Center for Plant Systems Biology VIB9052 GentBelgium department of Biomolecular Medicine Ghent University9000 GhentBelgium Center for Medical Biotechnology VIB9000 GhentBelgium Laboratoire de Biologie et Pathologie Végétales(LBPV) Equipe d’Accueil 1157Universitéde Nantes44000 NantesFrance institute for Biology Humboldt-Universit€at zu Berlin10115 BerlinGermany UniversitéParis-Saclay CEACNRSInstitute for Integrative Biology of the Cell(I2BC)91198Gif-sur-YvetteFrance UniversitéParis-Saclay CNRSInstitut de Chimie des Substances NaturellesUPR 230191198Gif-sur-YvetteFrance

Phelipanche ramosa is an obligate root-parasitic weed that threatens major crops in central *** order to germinate,it must perceive various structurally divergent host-exuded signals,including isothiocyanates(ITCs)and strigolactones(SLs).However,the receptors involved are still ***,we identify five putative SL receptors in *** and show that PrKAI2d3 is involved in the stimulation of seed *** demonstrate the high plasticity of PrKAI2d3,which allows it to interact with different chemicals,including *** SL perception mechanism of PrKAI2d3 is similar to that of endogenous SLs in non-parasitic *** provide evidence that PrKAI2d3 enzymatic activity confers hypersensitivity to ***,we demonstrate that methylbutenolide-OH binds PrKAI2d3 and stimulates *** germination with bioactivity comparable to that of *** study demonstrates that *** has extended its signal perception system during evolution,a fact that should be considered for the development of specific and efficient biocontrol methods.

关键词： a/b-hydrolase receptor seed germination stimulant strigolactones isothiocyanates Phelipanche ramosa

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.

New Hemisynthetic Oleanane Saponin with Antimicrobial Activities

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Advances in Biological Chemistry 2021年第1期11卷 1-11页

作者： Cyrille Ngoufack Tagousop Jean-de-Dieu Tamokou Leonel Donald Tsamo Feugap Dominique Harakat Laurence Voutquenne-Nazabadioko David Ngnokam department of Basic Scientific Studies University Institute of Technology University of Ngaoundere Ngaoundere Cameroon Research Unit of Environmental and Applied Chemistry Department of Chemistry Faculty of Science University of Dschang Dschang Cameroon Research Unit of Microbiology and Antimicrobial Substances Department of Biochemistry Faculty of Science University of Dschang Dschang Cameroon Service Commun d’Analyses Institut de Chimie Moléculaire de Reims (ICMR) CNRS UMR 7312 Reims France Groupe Isolement et Structure Institut de Chimie Moléculaire de Reims (ICMR) CNRS UMR 7312 Reims France

A new hemisynthetic oleanane saponin: 4',2",3",4",6"-penta-O-acetyl-6'-O- methyl-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl oleanolic acid (2) was obtained after acetylation and methylation reaction on 3-O... 详细信息

关键词： Saponin Acetylation Methylation Antimicrobial Activities

Qualitative determination of Photodegradation Products of Progesterone and Testosterone in Aqueous Solution

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American Journal of Analytical Chemistry 2016年第1期7卷 22-33页

作者： Ladji Méité Baba Donafologo Soro Narcisse Kouassi Aboua Véronique Mambo Karim Sory Traoré Patrick Mazellier Joseh de Laat Laboratoire des Sciences de l’Environnement Unité de Formation et de Recherche des Sciences et Gestion de l’Environnement Université Nangui Abrogoua Abidjan Cote d’Ivoire CNRS-UMR 5805 EPOC Laboratoire de Physico et Toxico Chimie de l’Environnement Université de Bordeaux Bordeaux France institut de chimie des Milieux et Matériaux de Poitiers (UMR CNRS 7285) Equipe Eaux Géochimie Santé Ecole Nationale Supérieure d’Ingénieurs de Poitiers Université de Poitiers Poitiers France

Direct photochemical degradations of progesterone (PR) and testosterone (TR), two naturally produced hormones, have been conducted in non-buffered aqueous solution (pH ranging between 5.5 and 6.0). The irradiation experiments were carried out in a batch reactor upon monochromatic (254 nm) and polychromatic (λ > 290 nm) at 25°C. GLC/MS and LC/UV-DAD/MS analyses were performed to investigate phototransformation products after a solid phase extraction (SPE) step for analytes concentration. For each compound several by-products have been identified and are the same ones under both irradiation conditions. Because of the presence of the same chromophore (α, β-unsaturated group) absorbing UV radiations in both hormones, the majority of chromatographic peaks correspond to by-products formed according to identical mechanisms involving isomerization, enolization, oxidation and hydration to lead to the generation of lumiketone, cyclopentenone, spiro-hydration, oxidation and hydroxylation photoproducts.

关键词： Photoproducts Testosterone Progesterone GLC/MS LC/UV-DAD/MS