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Direct oxidation of methane at low temperature using Pt/c,Pd/c,Pt/c-ATO and Pd/c-ATO electrocatalysts prepared by sodium borohydride reduction process

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燃料化学学报 2018年第9期46卷 1137-1145页

作者： J.Nandenha E.H.Fontes R.M.Piasentin F.c.Fonseca A.O.Neto Instituto de Pesquisas Energéticas e Nucleares IPEN/CNEN-SPAv.Prof.Lineu Prestes2242 Cidade UniversitáriaCEP 05508-000Sao PauloSPBrazil

The main objective of this paper was to characterize the voltammetric profiles of the Pt/c,Pt/c-ATO,Pd/c and Pd/cATO electrocatalysts and study their catalytic activities for methane oxidation in an acidic electrolyte at 25 ℃ and in a direct methane proton exchange membrane fuel cell at 80 ℃. The electrocatalysts prepared also were characterized by X-ray diffraction( XRD) and transmission electron microscopy( TEM). The diffractograms of the Pt/c and Pt/c-ATO electrocatalysts show four peaks associated with Pt face-centered cubic( fcc) structure,and the diffractograms of Pd/c and Pd/c-ATO show four peaks associated with Pd face-centered cubic( fcc) structure. For Pt/c-ATO and Pd/c-ATO,characteristic peaks of cassiterite( SnO_2) phase are observed,which are associated with Sb-doped SnO_2( ATO) used as supports for electrocatalysts. cyclic voltammograms( cV) of all electrocatalysts after adsorption of methane show that there is a current increase during the anodic scan. However,this effect is more pronounced for Pt/c-ATO and Pd/c-ATO. This process is related to the oxidation of the adsorbed species through the bifunctional mechanism,where ATO provides oxygenated species for the oxidation of cO or HcO intermediates adsorbed in Pt or Pd sites. From in situ ATR-FTIR( Attenuated Total Reflectance-Fourier Transform Infrared) experiments for all electrocatalysts prepared the formation of HcO or cO intermediates are observed,which indicates the production of carbon dioxide. Polarization curves at 80 ℃in a direct methane fuel cell( DMEFc) show that Pd/c and Pt/c electroacatalysts have superior performance to Pd/c-ATO and Pt/c-ATO in methane oxidation.

关键词： sodium borohydride reduction process Pt/c-ATO and Pd/c-ATO electrocatalysts methane oxidation acidic electrolytes polarization curves

Rice Protein Tagging Project:A call for International collaborations on Genome-wide In-Locus Tagging of Rice Proteins

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Molecular Plant 2020年第12期13卷 1663-1665页

作者： Yuming Lu Pamela c.Ronald Bin Han Jiayang Li Jian-Kang Zhu Shanghai center for Plant Stress Biology CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina Department of Plant Pathology and the Genome center University of CaliforniaDavisCAUSA National center for Gene Research CAS Center for Excellence in Molecular Plant SciencesChinese Academy of SciencesShanghaiChina State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(Beijing)Institute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijingChina Department of Horticulture and Landscape Architecture Purdue UniversityWest LafayetteINUSA

In September 1997,the International Rice Genome Sequencing Project was *** initiative pooled the resources of ten nations to obtain the first complete rice genome sequence,and promoted rice research and breeding into the post-genomics era(Li et al.,2018).In 2008,an internationally coordinated project named "RIcE2020" was proposed to systematically and fully characterize all rice genes,transcripts,and proteins(Zhang et al.,2008).While genes and their transcripts can be readily characterized by sequencing-and PcR-based methods,the characterization of protein dynamics including protein levels,subcellular localizations,post-transla-tional modifications,and interactions with macromolecules(e.g.,proteins,DNA,RNA,carbohydrates,and lipids)and small molecules(e.g.,metabolites and ligands)is much more challenging and usually requires antibodies that specifically recognize the protein of *** it is very difficult to systematically produce reliable antibodies for the specific recognition of individual plant proteins,a common practice is to transform a tag-fused open reading frame(ORF)of a gene to the corresponding loss-of-function mutant ***,such an ectopically expressed tagged protein may not fully reca-pitulate the properties of the endogenous protein due to the random insertion of the transgene,even when the transgene is expressed under the endogenous gene promoter.A preferred so-lution is to genetically label the coding sequence of the gene of interest,at its in vivo locus,with a sequence encoding a fluores-cent protein tag or an affinity tag such as FLAG or *** "in-locus" protein tagging,as we are naming it here,has been carried out genome-wide in yeast,caenorhabditis elegans,fly,and mammalian cultured cells,greatly facilitating the characterization of proteins in these organisms(Jiang et al.,2018).In 2017,a Genome Tagging Project was launched in mice,aiming to label every protein using a cRISPR/cas9-based "artificial spermatids"method(

关键词： breeding Genome endogenous

Deliberate external pancreatic fistula after pancreaticoduodenectomy performed in the setting of acute pancreatitis, and its internalization through fistula-jejunostomy

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Hepatobiliary & Pancreatic Diseases International 2020年第1期19卷 94-96页

作者： Sorin T Alexandrescu Andrei c Zlate Razvan T Grigorie Mihnea Ionescu Irinel Popescu Fundeni clinical Institute Dan Setlacec Centre of General Surgery and Liver TransplantationSos.Fundeni nr.258sector 2BucharestRomania carol Davila University of Medicine and Pharmacy BucharestRomania Titu Maiorescu University Faculty of MedicineBucharestRomania

To the Editor:Many patients with tumors of the pancreatic head or of the ampulla of Vater require endoscopic manipulation of the duodenal papilla in order to achieve tumor biopsy or for common bile duct *** interventional endoscopy approaches may lead to acute *** iatrogenic acute pancreatitis will influence the surgical strategy in patients scheduled for pancreaticoduodenectomy(PD).Due to the small number of cases,the surgical strategy in patients who require PD in the context of acute pancreatitis has not been standardized.

关键词： pancreatitis acute Vater

Structural and optoelectronic properties of sprayed Sb:SnO_2 thin films:Effects of substrate temperature and nozzle-to-substrate distance

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Journal of Semiconductors 2011年第10期32卷 1-9页

作者： A.R.Babar S.S.Shinde A.V.Moholkar c.H.Bhosale K.Y.Rajpure Electrochemical Materials Laboratory Department of PhysicsShivaji University

The influence of substrate temperature and nozzle-to-substrate distance（NSD） on the structural,morphological, optical and electrical properties of Sb：SnO_2 thin films prepared by chemical spray pyrolysis has been *** structural,morphological,optical and electrical properties were characterized by using XRD,SEM, UV-visible spectrophotometry and Hall effect measurement *** was seen that the films are polycrystalline, having a tetragonal crystal structure with strong orientation along the（200） *** pyramidal crystallites formed due to coalescence were observed from SEM *** values of highest conductivity,optical transmittance and figure of merit of about 1449（Ω·cm）^（-1）,70%and 5.2×10^（-3）□/Ω,respectively,were observed for a typical film deposited using optimal conditions（substrate temperature = 500℃and NSD = 30 cm）.

关键词： substrate temperature NSD structural optoelectronic properties

Homotopy analysis solutions for the asymmetric laminar flow in a porous channel with expanding or contracting walls

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Acta Mechanica Sinica 2011年第2期27卷 208-214页

作者： X.-H. Si L.-c. Zheng X.-X. Zhang Y. chao Applied Science School University of Science and Technology Beijing 100083 Beijing China Department of Mechanical Engineering University of Science and Technology Beijing100083 Beijing China Research Institute of chemical Defense of the EL.A 102205 Beijing China

In this paper, the asymmetric laminar flow in a porous channel with expanding or contracting walls is investigated. The governing equations are reduced to ordinary ones by using suitable similar transformations. Homotopy analysis method （HAM） is employed to obtain the expres- sions for velocity fields. Graphs are sketched for values of parameters and associated dynamic characteristics, especially the expansion ratio, are analyzed in detail.

关键词： Homotopy analysis method · Expanding or contracting wall · Asymmetric laminar flow · Porous channel · Expansion ratio

Severe dengue associated with aseptic meningitis, acute kidney injury, and sudden sensorineural hearing loss: A case report

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Asian Pacific Journal of Tropical Medicine 2021年第4期14卷 187-190页

作者： Renan GM Diniz Elaine c dos Santos Gabriel cL chagas Elizabeth F Daher Department of Internal Medicine Faculty of MedicineFederal University of CearaCearaBrazil Department of Intensive care Unit Fortaleza General HospitalFortalezaCearaBrazil Post-Graduation Program in Medical Sciences Department of Internal MedicineFederal University of CearaFortalezaCearaBrazil

Rationale:Dengue is the most important human arboviral *** manifestations occur rarely in *** the best of our knowledge,there is only one reported case of dengue-associated sudden sensorineural hearing loss(SSNHL)in Brazil untill *** concerns:A 42-year-old man was presented to the emergency department with unconsciousness and generalized tonicclonic ***:Dengue-associated aseptic meningitis,acute kidney injury,and ***:The patient was treated with anticonvulsants and thiamine and underwent mechanical *** received combined ceftriaxone and acyclovir,which were later switched to meropenem,acyclovir and ampicillin empirically until culture results became *** also required hemodialysis and plasmapheresis sessions and fresh frozen plasma and buffy coat transfusions until definitive ***:The patient was discharged after improvement of his general condition and of his blood test results,but hearing loss remained.A six-month follow-up visit showed persistent ***:Dengue should be included in the differential diagnosis of patients from dengue-endemic areas presenting an acute febrile disease with neurological *** the best of our knowledge,this is the second reported case of dengueassociated SSNHL,suggesting an association between dengue and development of SSNHL.

关键词： Dengue Aseptic meningitis Acute kidney injury Sensorineural hearing loss Deafness

Improvement of strength and ductility synergy in a room-temperature stretch-formable Mg-Al-Mn alloy sheet by twin-roll casting and low-temperature annealing

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Journal of Magnesium and Alloys 2022年第4期10卷 1066-1074页

作者： T.Nakata c.Xu K.Kaibe Y.Yoshida K.Yoshida S.Kamado Nagaoka University of Technology 1603-1KamitomiokaNagaoka 940-2188Japan School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001China Sumitomo Electric Industries Ltd.1-1-1 KoyakitaItami 664-0016Japan

Strength and ductility synergy in an Mg-3mass%Al-Mn(AM30)alloy sheet was successfully improved via twin-roll casting and annealing at *** AM30 alloy sheet produced by twin-roll casting,homogenization,hot-rolling,and subsequent annealing at 170℃ for 64 h exhibits a good 0.2%proof stress of 170 MPa and a large elongation to failure of 33.1%along the rolling *** sheet also shows in-plane isotropic tensile properties,and the 0.2%proof stress and elongation to failure along the transverse direction are 176 MPa and 35.5%,*** the sheet produced by direct-chill casting also shows moderate strengths if the annealing condition is same,the direct-chill casting leads to the deteriorated elongation to failure of 23.9%and 30.0%for the rolling and transverse directions,*** well as such excellent tensile properties,a high room-temperature stretch formability with an Index Erichsen value of 8.3 mm could be obtained in the twin-roll cast sheet annealed at 170℃ for 64 *** annealing at a higher temperature further improves the stretch formability;however,this results in the decrease of the tensile *** characterization reveals that the excellent combination of strengths,ductility,and stretch formability in the twin-roll cast sheet annealed at the low-temperature annealing is mainly attributed to the uniform recrystallized microstructure,fine grain size,and circular distribution of(0001)poles away from the normal direction of the sheet.

关键词： Magnesium Rolling Tensile property Room temperature formability Twinning

Preparation and Microstructural characterization of Activated carbon-Metal Oxide Hybrid catalysts:New Insights into Reaction Paths

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Journal of Materials Science & Technology 2015年第8期31卷 806-814页

作者： A.Barroso-Bogeat M.Alexandre-Franco c.Fernndez-Gonzlez V.Gómez-Serrano Department of Organic and Inorganic chemistry Faculty of SciencesUniversity of Extremadura

In catalysis processes, activated carbon （Ac） and metal oxides （MOs） are widely used either as catalysts or as catalyst supports because of their unique properties. A combination of Ac and MO nanoparticles in a single hybrid material usually entails both chemical and microstructural changes, which may largely influence the potential catalytic suitability and performance of the resulting product. Here, the prepa- ration of a wide series of Ac-MO hybrid catalysts is studied. Three series of such catalysts are prepared by support first of MO （Al2O3, Fe2O3, SnO2, TiO2, WO3, and ZnO） precursors on a granular Ac by wet impregnation and oven-drying at 120 ℃, and by subsequent heat treatment at 200 or 850℃ in inert atmosphere. Both the chemical composition and microstructure are mainly investigated by powder X-ray diffraction. Yield and ash content are often strongly dependent on the MO precursor and heat treatment temperature, in particular for the Sn catalysts. With the temperature rise, trends are towards the transformation of metal hydroxides into metal oxides, crystallinity improvement, and occurrence of drastic composition changes, ultimately leading to the formation of metals in elemental state and even metal carbides. Reaction paths during the preparation are explored for various hybrid catalysts and new insights into them are provided.

关键词： Activated carbon Metal oxides Hybrid catalysts Preparation Microstructural characterization X-ray diffraction

A comparative study of the sorption of O-PAHs and PAHs onto soils to understand their transport in soils and groundwater

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Journal of Environmental Sciences 2023年第2期124卷 61-75页

作者： W.Almouallem J.Michel S.Dorge c.Joyeux G.Trouve D.Le Nouen French National Institute for Industrial and Environment and Risks Direction Sites&TerritoiresVerneuil en HalatteF-60550France University of Haute-Alsace Laboratoire Gestion des Risques et Environnement(LGRE)UR2334MulhouseFrance University of Strasbourg 67000 StrasbourgFrance University of Haute-Alsace Laboratoire d’Innovation Moléculaire et Applications(LIMA)UMR 7042 CNRSMulhouseFrance

Polycyclic aromatic hydrocarbons(PAHs)and their oxygenated derivates(O-PAHs)are identified in soils and groundwater of industrialized sites and contribute to the risk for Humans and the ***,data are scarce in literature concerning their retention and transfer in soils and no soil-water partition coefficients are available for these *** of two PAHs,fluorene and acenaphthene and two O-PAHs,9H-fluorenone and dibenzofuran onto two soils with different organic carbon contents was evaluated and compared by determining their sorption *** of ionic strength and liquid to solid ratio,on fluorene and fluorenone sorption was also *** equilibrium is achieved within less than 24 hr of mixing and linear sorption models best fit the isotherm *** and dibenzofuran are similarly sorbed onto the *** of fluorene is higher than the one of fluorenone,showing a smaller affinity of fluorenone towards the solid *** means that O-PAH could form larger contamination plumes in groundwater than *** the L/S ratio from 100 to 50 and 30,increases the sorption of fluorenone onto the soil by 56% and 67%respectively,while the sorption of fluorene is slightly *** the ionic strength of the aqueous phase also modifies the sorption of fluorenone,contrary to the sorption of fluorene which is slightly affected.

关键词： PAHs O-PAHs contaminated soils Groundwater Sorption Kinetics Isotherms