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Influence of ZrO_(2)/siO_(2) nanomaterial incorporation on the properties of PEO layers on Mg-Mn-Ce alloy

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Journal of Magnesium and Alloys 2022年第2期10卷 552-566页

作者： d.V.Mashtalyar I.M.Imshinetskiy K.V.Nadaraia A.s.Gnedenkov s.l.sinebryukhov A.Yu.Ustinov A.V.samokhin s.V.Gnedenkov Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russian Federation Far Eastern Federal University Vladivostok 690922Russian Federation A.A.Baikov Institute of Metallurgy and Materials science Russian Academy of SciencesMoscow 119991Russian Federation

The properties of coatings formed on the MA8 magnesium alloy by the plasma electrolytic oxidation in electrolytes containing mechanical mixture of zirconia and silica nanoparticles in concentrations of 2,4 and 6 g/l have been *** has been established by sEM,Eds,and XPs that ZrO_(2)/siO_(2)nanoparticles successfully were incorporated into the ***-Raman spectroscopy showed the presence of ZrO_(2)in tetragonal and monoclinic forms in the PEO-coating composition as well as Mg_(2)siO_(4) in tetrahedral configuration uniformly distributed in the outer part of *** coatings significantly reduce corrosion current density in comparison with bare Mg alloy and base PEOlayer(from 2.4×10^(–7)A/cm^(2) for base PEO layer to 0.7×10^(–7)A/cm^(2) for coatings with nanoparticles).It has been found that the presence of solid nanoparticles in the composition of coating has a positive effect on their hardness(this parameter was increased from 2.1±0.3 GPa to 3.1±0.4 GPa)and wearproof(the wear was reduced from(4.3±0.4)×10^(–5)mm^(3)/(N×m)to(3.5±0.2)×10^(–5)mm^(3)/(N×m)).

关键词： Plasma electrolytic oxidation Composite coatings Nanoparticles Zirconia silica Protective coatings

solar-assisted photocatalytic water splitting using defective UiO-66 solids from modulated synthesis

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Nano Research 2024年第5期17卷 4134-4150页

作者： Celia M.Rueda-Navarro María Cabrero-Antonino Paula Escamilla Valentín díez-Cabanes dong Fan Pedro Atienzar Belén Ferrer Ignacio Vayá Guillaume Maurin Herme G.Baldoví sergio Navalón departamento de Química Universitat Politècnica de ValènciaCamino de Vera s/nValencia 46022Spain Instituto de Ciencia Molecular(ICMOl) Universitat de ValènciaPaterna 46980Spain ICGM Univ.MontpellierCNRSENSCMMontpellier34095France Instituto de Tecnología Química(UPV-CsIC) Universitat Politècnica de ValènciaAvenida de los Naranjos s/nValencia 46022Spain

Metal-organic frameworks(MOFs)are attracting increasing interests as photocatalysts for solar-driven hydrogen production from *** paper reports on a comparative study of using either acetic acid(AA)or trifluoroacetic acid(TFA)as the representative UiO-66 organic modulators for synthesizing visible light responsive UiO-66(Zr)-X(X:NH_(2) or NO_(2))photocatalysts for water *** results show that photocatalytic hydrogen generation from a water/methanol mixture can be improved by varying the nature and amount of the modulator employed to prepare the different UiO-66(Zr)-X(X:NH_(2) or NO_(2))solid ***-66(Zr)-NH_(2) was the most active photocatalyst,followed by UiO-66(Zr)-NO_(2),both prepared with 12 equivalents of AA with respect to the organic *** UiO-66(Zr)-NH_(2) solid was more active than the parent MOF in photocatalytic overall water splitting(OWs)(H_(2) and O_(2) production of 450 and 160μmol·g^(-1),respectively,in 5 h;apparent quantum yield(AQY)at 400 nm of 0.06%)in the absence of methanol and compares favourably with analogous *** on the photocatalytic activity of the most active solids of both series was obtained by means of a series of techniques,including ultraviolet-visible(UV-vis)diffuse reflectance,X-ray photoelectron spectroscopy(XPs),laser flash photolysis(lFP),electron spin resonance(EsR),photoluminescence and photoelectrochemical measurements together with density functional theory(dFT)*** results showed that organic acid modulators can be used to enhance the photocatalytic activity of missing linker UiO-66 defective materials in solar-powered water splitting.

关键词： heterogeneous photocatalysis metal-organic frameworks(MOFs) UiO-66 materials carboxylic acid modulators water splitting solar light

Evolution of microstructure and texture in copper during repetitive extrusion-upsetting and subsequent annealing

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Journal of Materials science & Technology 2017年第7期33卷 690-697页

作者： Q.Chen d.Y.shu J.lin Y.Wu X.s.Xia s.H.Huang Z.d.Zhao O.V.Mishin G.l.Wu state Key laboratory of Mechanical Transmission Chongqing University Chongqing 400044 China

The evolution of the microstructure and texture in copper has been studied during repetitive extrusionupsetting（REU） to a total von Mises strain of 4.7 and during subsequent annealing at different temperatures. It is found that the texture is significantly altered by each deformation pass. A duplex 001 ＋ 111 fiber texture with an increased 111 component is observed after each extrusion pass,whereas the 110 fiber component dominates the texture after each upsetting pass. during REU, the microstructure is refined by deformation-induced boundaries. The average cell size after a total strain of 4.7 is measured to be ~0.3 μm. This refined microstructure is unstable at room temperature as is evident from the presence of a small number of recrystallized grains in the deformed matrix. Pronounced recrystallization took place during annealing at 200？C for 1 h with recrystallized grains developing predominantly in high misorientation regions. At 350？C the microstructure is fully recrystallized with an average grain size of only 2.3 μm and a very weak crystallographic texture. This REU-processed and subsequently annealed material is considered to be potentially suitable for using as a material for sputtering targets.

关键词： severe plastic deformation Repetitive extrusion-upsetting Copper deformation microstructure Texture Annealing

Integrative Analysis of Transcriptome and Phenolic Compounds Profile Provides Insights into the Quality of soursop (Annona muricata l.) Fruit

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1717-1732页

作者： Yolotzin Apatzingán Palomino-Hermosillo Ángel Elpidio díaz-Jasso Rosendo Balois-Morales Verónica AlhelíOchoa-Jiménez Pedro Ulises Bautista-Rosales Guillermo Berumen-Varela Unidad de Tecnología de Alimentos-secretaría de Investigación y Posgrado Universidad Autónoma de Nayarit.Ciudad de la Cultura SNTepic63000NayaritMéxico Programa Académico de Biología Unidad Académica de AgriculturaUniversidad Autónoma de NayaritKm.9.Carretera Tepic-CompostelaXalisco63780NayaritMéxico Estancias Posdoctorales-Consejo Nacional de Humanidades Ciencias y TecnologíasCoordinación de Apoyos a Becarios e InvestigadoresDirección de PosgradoCiudad de México03940México

soursop(Annona muricata l.)is a tropical fruit highly valued for its uniqueﬂavor,nutritional value,and health-promoting *** ripening process of soursop involves complex changes in gene expression and metabo-lite accumulation,which have been studied using various omics *** analysis has provided insights into the regulation of key genes involved in ripening,while metabolic compound analysis has revealed the presence of numerous bioactive compounds with potential health beneﬁ***,the integration of transcrip-tome and metabolite compound data has not been extensively explored in ***,in this paper,we present a comprehensive analysis of the transcriptome and phenolic compound proﬁles of soursop during *** integration analysis showed that the genes and phenolic compounds were mainly involved in the starch and sucrose metabolism pathways during soursop ***,the phenolic compounds Kaempferol 3-Q-galactoside,Procyanidin C1,Procyanidin trimmer C1,and m-Coumaric,as well as the genes Ubiquitin-like protein 5(UBl5_ARATH),ATP-dependent zinc metalloprotease FTsH8(FTsH8_ORYsJ),Zinc transporter 4(ZIP4_AR-ATH),Thioredoxin-like 3-1(TRl31_ORYsJ),Mitogen-activated protein kinase YOdA(YOdA_ARATH),R-man-delonitrile lyase-like(MGl_ARATH),26s protease regulatory subunit 6A homolog(PRs6_sOllC),Cytochrome P45072A13(C7A13ARATH),Cytochrome P45084A1(C84A1_ARATH)and Homoserine O-trans-acetylase(MET2-ORYsJ)were correlated and differentially accumulated and expressed,*** study provides new insights into the molecular mechanisms underlying soursop ripening and may contribute to the development of strategies for improving the nutritional quality and shelf life of this important fruit.

关键词： Bioinformatics data integration genes metabolites postharvest storage ripening

Effect of Icosahedral Phase on Crystallographic Texture and Mechanical Anisotropy of Mg–4%li Based Alloys

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Journal of Materials science & Technology 2017年第5期33卷 475-480页

作者： C.Q.li d.K.Xu s.Yu l.Y.sheng E.H.Han school of Materials science and Engineering Northeastern University CAs Key laboratory of Nuclear Materials and safety Assessment Institute of Metal Research Chinese Academy of Sciences school of Materials science and Engineering Shenyang Aerospace University shenzhen Institute Peking University Shenzhen Key Lab Human Tissue Regenerate & Repair

Through investigating and comparing the microstructure and mechanical properties of the as-extruded Mg alloys Mg-4%li and Mg-4%li-6%Zn-l.2%Y （in wt%）, it demonstrates that although the formation of I-phase （Mg3Zn6Y, icosahedral structure） could weaken the crystallographic texture and improve the me- chanical strength, the mechanical anisotropy in terms of strength remains in Mg-4%li-6%Zn-1.2%Y alloy. Failure analysis indicates that for the Mg-4%li alloy, the fracture surfaces of the tensile samples tested along transverse direction （Td） contain a large number of plastic dimples, whereas the fracture surface exhibits quasi-cleavage characteristic when tensile samples were tested along extrusion direction （Ed）. For the Mg-4%li-6%Zn-I.2%Y alloy, typical ductile fracture surfaces can be observed in both ＂Td＂ and ＂Ed＂ samples. Moreover, due to the zonal distribution of broken l-phase particles, the fracture surface of ＂Td＂ samples is characterized by the typical ＂woody fracture＂.

关键词： Mg-li alloy Texture Mechanical anisotropy Fracture

Response of C and N cycles to N fertilization in sphagnum and Molinia-dominated peat mesocosms

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Journal of Environmental sciences 2019年第3期31卷 264-272页

作者： Fabien leroy sébastien Gogo Christophe Guimbaud André-Jean Francez Renata Zocatelli Christian défarge léonard Bernard-Jannin Zhen Hu Fatima laggoun-défarge University of Orleans ISTO CNRs ISTO BRGM ISTO University of Orleans LPC2E CNRs LPC2E UMR CNRs 6553 ECOBIO University of Rennes 1 University of Orleans Cellule R&D CETRAHE school of Environmental science and Engineering Shandong University

Plant communities play an important role in the C-sink function of peatlands. However,global change and local perturbations are expected to modify peatland plant communities,leading to a shift from sphagnum mosses to vascular plants. Most studies have focused on the direct effects of modification in plant communities or of global change(such as climate warming, N fertilization) in peatlands without considering interactions between these disturbances that may alter peatlands' C function. We set up a mesocosm experiment to investigate how Greenhouse Gas(CO_2, CH_4, N_2O) fluxes, and dissolved organic carbon(dOC)and total dissolved N(TN) contents are affected by a shift from sphagnum mosses to Molinia caerulea dominated peatlands combined with N fertilization. Increasing N deposition did not alter the C fluxes(CO_2 exchanges, CH_4 emissions) or dOC content. The lack of N effect on the C cycle seems due to the capacity of sphagnum to efficiently immobilize N. Nevertheless, N supply increased the N_2O emissions, which were also controlled by the plant communities with the presence of Molinia caerulea reducing N_2O emissions in the sphagnum mesocosms. Our study highlights the role of the vegetation composition on the C and N fluxes in peatlands and their responses to the N deposition. Future research should now consider the climate change in interaction to plants community modifications due to their controls of peatland sensitivity to environmental conditions.

关键词： CO2 and CH4 N2O Peatland Plant community composition sphagnum moss Graminoid

liver histological changes and lipid peroxidation in the amphibian Ambystoma mexicanum induced by sediment elutriates from the lake Xochimilco

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Journal of Environmental sciences 2016年第8期28卷 156-164页

作者： Esperanza Ortiz-Ordonez Eugenia lópez-lópez Jacinto Elías sedeno-díaz Esther Uría Ignacio Andrés Morales María Estela Pérez Mineko shibayama Instituto Politécnico Nacional Depto.de Formación Básica e InterdisciplinariaCICS-USTAv.de los Maestros s/n.Col.Sto Instituto Politécnico Nacional Laboratorio de Evaluación de la Salud de Ecosistemas AcuáticosENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Instituto Politécnico Nacional Coordinación Politécnica para la SustentabilidadEdificio de la Biblioteca Nacional3er PisoAv.Instituto Politécnico Nacional s/nesq.Wilfrido MassieuCol Instituto Politécnico Nacional Laboratorio de HistologíaENCBProl.de Carpio y Plan de Ayala s/n.Col.Sto Unidad de servicio Académico Acuario BiologíaFacultad de CienciasUniversidad Autónoma de MéxicoCiudad Universitaria laboratorio de Infectómica Centro de Investigación y de Estudios Avanzados del IPNAv.Instituto Politécnico Nacional

lacustrine sediments accumulate pollutants that input from the lake watershed and can be released to the water column by sediment resuspension; thus, pollutants can change their bioavailability and exert adverse effects to aquatic biota. shallow-urban lakes are particularly susceptible to receive pollutants from urban discharges and sediment resuspension. lake Xochimilco, in Mexico City, an urban-shallow lake, faces multiple problems： urban sprawl, overexploitation of aquifers, drying of springs, discharge of wastewater from treatment plants, and sediment resuspension. The aquatic biota living in this ecosystem is continuously exposed to the release of pollutants from the sediments. We assessed the risk that pollutants released from sediments from lake Xochimilco, Touristic（TZ） and Agriculture zone（AZ）, can exert on a native amphibian species of the lake（Ambystoma mexicanum） through exposure bioassays to sediment elutriates. We evaluate alterations in the amphibian by three approaches： biochemical（level of lipid peroxidation,lPO）, cellular（ultrastructure） and the liver histology of A. mexicanum and we compare them with a batch control. Additionally, we assessed heavy metals（Pb, Cd and Hg） in *** from TZ showed the highest concentrations of the metals assessed. Organisms exposed to sediment elutriates from either study sites showed higher lPO values than control organisms（p 〈 0.05）. Organisms exposed to elutriates from the TZ showed the most conspicuous damages： hepatic vas.d.l.tion of sinusoids, capillaries with erythrocytes,leukocyte infiltration and cytoplasmic vacuolation in hepatocytes. The biological responses assessed reflected the risk that faces A. mexicanum when is exposed for prolonged periods to sediment resuspension in lake Xochimilco.

关键词： Elutriates Amphibian liver Histological alterations Ultrastructure Oxidative stress Metals Urban lake

low-Frequency dependence of Conductivity and dielectric Properties of Polyaniline/ZnFe_(2)O_(4) Nanocomposites

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Chinese Physics letters 2011年第11期28卷 218-221页

作者： G.d.Prasanna H.s.Jayanna Ashok R lamani M.l.dinesha C.s.Naveen G.J.shankaramurthy department of PG studies and Research in Physics Kuvempu UniversityShankarghatta-577451KarnatakaIndia Bapuji Institute of Engineering and Technology Davangere-577004KarnatakaIndia

Conducting polyaniline/ZnFe_(2)O_(4) nanocomposites are synthesized by using a simple and inexpensive one-step in-situ polymerization method in the presence of ZnFe2O4 *** structural,morphological and electrical properties of the samples are characterized by x-ray diffraction,Fourier transform infrared spectra and scanning electron *** results reveal the formation of polyaniline/ZnFe2O4 *** morphology of these samples is studied by scanning electron ***,the ac conductivity(σac)of these composites is investigated in the frequency range of 1 kHz–10 *** presence of polarons and bipolarons are responsible for the frequency dependence of ac conductivity in these *** ac conductivity is found to be constant up to 1MHz and thereafter it increases *** ac conductivity of 0.695 s・cm^(−1) at room temperature is observed as the maxima for the polyaniline with 40wt%of the ZnFe2O4 nanocomposite.

关键词： composites ZnFe2O4 conductivity

Electrochemical synthesis of boron-containing coatings on Mg alloy for thermal neutron shielding

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Journal of Magnesium and Alloys 2023年第10期11卷 3779-3789页

作者： K.V.Nadaraia s.N.suchkov N.s.Markin I.M.Imshinetskiy s.I.Ivannikov d.V.Mashtalyar A.Yu.Ustinov s.l.sinebryukhov s.V.Gnedenkov Institute of Chemistry FEB RAs 159 Pr.100-Letiya VladivostokaVladivostok 690022Russia

The work provides the results of the one-step formation of boron-containing coatings on an Mg–Mn–Ce alloy by plasma electrolytic oxidation. The results of studies of the composition, structure and morphology of heteroxide coatings are presented. It was established that the boron is contained in the coating mainly in the form of B or B_(2)O_(3). The introduction of B changes the color of coatings, and also helps to increase their porosity. The method of determining the full cross section of the interaction of thermal neutron absorption efficiency by samples material using the installation of neutron-activation analysis based on ^(252)Cf was developed. It was shown that the introduction of boron into the formed coatings allows to increase the macroscopic cross-section of the interaction of samples with thermal neutrons by 3.8 times. This effect opens the potential for the use of synthesized material in the field of nuclear technologies and aerospace industry.

关键词： Plasma electrolytic oxidation Boron Neutron capture Neutron shielding Protective coatings