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PREPARATION AND CORROsION REsIsTANCE OF NiP/TiO_2 COMPOsITE FIlM ON CARBON sTEEl IN sUlFURIC ACID sOlUTION

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Acta Metallurgica sinica(English letters) 2006年第2期19卷 117-123页

作者： l.z. song s.z. song j. zhao school of Environment ＆ Chemical Engineering Yanshan University Qinhuangdao 066004 China school of Materials science and Engineering Tianjin University Tianjin 300072 China

A NiP/TiO2 composite film on carbon steel was prepared by electroless plating and sol-gel composite process. An artificial neural network was applied to optimize the prepared condition of the composite film. Corrosion behavior of the NiP/TiO2 composite film was investigated by polarization resistance measurement, anode polarization, EsEM （environmental scanning electron microscopy） and EIs （electrochemical impedance spectroscopy） measurements. Results showed that the NiP/ TiO2 composite film has a good corrosion resistance in 0.5mol/l H2sO4 solution. The element valence of the composite film was characterized by XPs （X-ray photoelectron spectroscopy） spectrum, and an anticorrosion mechanism of the composite film was discussed.

关键词： electroless plating and sol-gel composite process artificial neural network NiP/TiO2 composite film corrosion resistance

Four late-type Galaxies with Double Radio lobes and Properties of such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： z.s.Yuan X.Y.Gao z.l.Wen j.l.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAs Key laboratory of FAsT National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China school of Astronomy and space sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** samples are desired for a thorough investigation and *** util.zing the optical data from the newly released Dark Energy spectroscopic Instrument imaging surveys and the radio sources from the NRAO VlA sky survey and the Faint Images of the Radio sky at Twenty-centimeter,we identify four late-type Galaxies with double Radio lobes(la GRls):j0217-3645,j0947+6220,j1412+3723 and j1736+*** previously known la GRls,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)la GRls belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of la GRls are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

Three New spiral Galaxies with Active Nuclei Producing Double Radio lobes

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Research in Astronomy and Astrophysics 2023年第3期23卷 46-53页

作者： X.Y.Gao z.s.Yuan j.l.Han z.l.Wen s.s.shan National Astronomical Observatories Chinese Academy of SciencesBejing 10011China CAs Key laboratory of FAsT National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China school of Astronomy University of Chinese Academy of SciencesBeijing 100049China

Double radio lobes are generally believed to be produced by active nuclei of elliptical ***,several double-lobed radio sources have been solidly found to be associated with spiral *** cross-matching~9×105 spiral galaxies selected from the sloan Digital sky survey DR8 data with the full 1.4 GHz radio source catalogs of NRAO VlA sky survey and Faint Images of the Radio sky at Twenty-centimeters,we identify three new spiral galaxies:j0326-0623,j1110+0321 and j1134+3046 that produce double radio lobes,and five doublelobed spirals previously *** combining the newly discovered and all the other known cases in literature,we confirm the relation that more massive spiral galaxies could produce more powerful radio *** find that most of these spiral galaxies are located in a galaxy group or a poor cluster,in which the environment is denser than in the field,and about half of them are the central brightest galaxies in their parent *** therefore suggest that the environment is one of the key factors for a spiral to produce double radio lobes.

关键词： galaxies galaxy massive

Baird’s tapir density in high elevation forests of the Talamanca region of Costa Rica

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Integrative zoology 2012年第4期7卷 381-388页

作者： j.séF.gonzÁl.z-MAYA jan sCHIPPER Beth POlIDORO Annelie HOEPKER Diego zÁRRATE-CHARRY jerrold l.BElANT sierra to sea Institute ProCAT Internacional/ColombiaLas AlturasCoto BrusPuntarenasCosta Rica Instituto de Ecología Universidad Nacional Autónoma de México(IE-UNAM)Ciudad UniversitariaDFMexico Carnivore Ecology laboratory Forest and Wildlife Research CenterMississippi State UniversityMississippiUSA Big Island Invasive species Committee University of HawaiiHiloHawaiiUSA Old Dominion University NorfolkVirginiaUSA

Baird’s tapir(Tapirus bairdii)is currently endangered throughout its neotropical range with an expected popula--lished in Valle del silencio within Parque Internacional la Amistad(PIlA).seventy-seven tapir pictures of 15 individuals comprising 25 capture-recapture events were anal.zed using mark-recapture *** 100%minimum convex polygon of the sampled area was 5.7 km2 and the effective sampled area using half mean max-imum distances moved by tapirs was 7.16 *** estimated a tapir density of 2.93 individuals/km2 which rep-resents the highest density reported for this *** valleys can represent unique and important habitats for large mammal ***,the extent of isolation of this population,potentially constrained by steep slopes of the cordillera,remains *** genetic and movement studies are required to un-derstand meta-population dynamics and connectivity between lowland and highland areas for Baird’s tapir con-servation in Costa Rica.

关键词： camera trap capture Central America populations tapir

Development and application of functional gene arrays for microbial community analysis

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中国有色金属学会会刊：英文版 2008年第6期18卷 1319-1327页

作者： z. l. HE j. D. VAN NOsTRAND l.Y. WU j. z. zHOU Institute for Environmental Genomics Department of Botany and Microbiology University of Oklahoma Norman OK 73019 USA

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计... 详细信息

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计，样品准备，和数据分析提出很多挑战。这个工作集中于功能的基因数组(FGA ) 的开发和应用程序为微生物引起的社区研究指向关键功能的基因标记。一些与 FGA 有关明确地给问题调音，例如 oligonucleotide 探查设计， nucleic 酸抽取和纯化，数据分析，特性，敏感，和量的能力详细被讨论。最近的研究证明了 FGA 能从许多自然环境关于微生物引起的社区提供特定、敏感、潜在地量的信息并且控制生态系统。这种技术被期望革命化微生物引起的社区的分析，并且连接微生物引起的结构到生态系统工作。

关键词：微数列应用函数基因标记微生物种群

Mechanical Properties of a low-thermal-expansion Aluminum/silicon Composite Produced by Powder Metallurgy

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journal of Materials science & Technology 2014年第4期30卷 417-422页

作者： Y.Q.liu s.H.Wei j.z.Fan z.l.Ma T.zuo National Engineering & Technology Research Center for Nonferrous Metal Matrix Composites Beijing General Research Institute for Nonferrous Metals

AI matrix composite containing high volume fraction silicon has been promising candidate for lightweight and low-thermal-expansion components. Whereas, optimization of its mechanical properties still is an open challenge. In this article, a flexile powder metallurgy processing was used to produce a fully dense AI-4.0Cu （wt%） alloy composite reinforced with 65 vol.% si particles. In this composite, si particles were homogenously distributed, and the particle size was refined to the range of 3-15 μm. Tensile and flexural strength of the composite were 282 and 455 MPa, respectively, about 100% and 50% higher than the best properties reported in literature. The measured fracture toughness of the composite was 4.90 MPa m1/2. The improved strength of 65%si/AI was attributed to the optimized particle characteristics and matrix properties. This investigation is expected to provide a primary understanding of the mechanical behaviors of si/AI composites, and also promote the structural applications of this low-thermal-expansion material.

关键词： Aluminum matrix composite Powder metallurgy Mechanical properties Coefficient of thermal expansion Fracture

Examining the effect of the aging state on strength and plasticity of wrought aluminum alloys

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journal of Materials science & Technology 2022年第27期122卷 54-67页

作者： z.Qu z.j.zhang j.X.Yan P.zhang B.s.Gong s.l.lu z.F.zhang T.G.langdon shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaShenyang 110016China Department of Mechanical Engineering University of SouthamptonSouthampton SO171BJUnited Kingdom

A general rule of strength and plasticity was proposed for three typical wrought Al alloys(2xxx,6xxx,and 7xxx)subjected to different aging *** of the work-hardening processes and dislocation configurations in tensile and compressive testing reveal that this general rule arises because there is a common mechanism for these three kinds of wrought alloys whereby the tendency for cross-slip increases monotonously with aging *** anal.zing the strain hardening exponent and the stacking fault energy,it is demonstrated that the change in the dislocation slip mode is attributed mainly to the formation of second phases rather than to the matrix ***,a new work-hardening model was proposed for wrought Al alloys containing second phases and this explains the interaction between dislocations and second phases and other relevant experimental *** work is therefore beneficial for quantitatively investigating and optimizing the strength and plasticity of wrought aluminum alloys.

关键词： Wrought aluminum alloy strength and plasticity Work hardening Dislocation slip mode second phase

Embryo and Endosperm Phytochemicals from Polyembryonic Maize Kernels and Their Relationship with seed Germination

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Phyton-International journal of Experimental Botany 2022年第5期91卷 929-941页

作者： j.David García-Ortíz Rebeca gonzál.z-Centeno María Alejandra Torres-Tapia j.A.Ascacio-Valdés j.séEspinoza-Vel.zquez Raúl Rodríguez-Herrera Food Research Department School of ChemistryAutonomous University of CoahuilaSaltillo25280México Plant Breeding Department Universidad Autonoma Agraria Antonio Narro(UAAAN)Saltillo25315México

Because of the growing worldwide demand for maize grain,new alternatives have been sought for breeding of this cereal,e.g.,development of polyembryonic varieties,which agronomic performance could positively impact the grain yield per unit area,and nutritional *** objectives of this study were to(1)determine the phytochemicals present in the embryo and endosperm of grain from maize families with high,low,and null polyembryony frequency,which were planted at different locations,and(2)state the relationship between these compounds and seed *** extracted phytochemicals from corn were identified by *** results showed that the genotype with the highest presence of phytochemicals was the brachytic population with high polyembryony called“BAP”,which also required less water during the germination *** number of phytochemicals in both embryo and endosperm tissues was not related to the sowing location where they came from or the type of *** number of different phytochemicals depended on the grain tissue from where they were *** chemical compounds found in the different maize tissues were related to the development of the plant,either in roots or nibs because these are mainly associated with the lignin synthesis.

关键词： zea mays l HPlC-Ms locations kernels phytochemicals

Deformation behaviors of Cu bicrystals with an inclined twin boundary at multiple scales

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journal of Materials science & Technology 2017年第7期33卷 698-702页

作者： l.l.li z.j.zhang P.zhang j.Tan j.B.Yang z.F.zhang shenyaag National laboratory for Materials science lastitute of Metal Research Chinese Academy of Sciences Shenyaag 110016 China

Cu bicrystals of different sizes with a sole twin boundary（TB） inclined at 45？with respect to the loading direction were deformed under unidirectional and cyclic loading, respectively. It is found that the slip bands（sBs） parallel to the TB can be activated near the TB at all scales without obeying the schmid＇s *** is concerned with the local stress enhancement in the macroscale while it is more closely related to the scarce dislocation sources in the microscale. Moreover, a wedge-shaped zone formed near the TB in the microscale ascribed to the limited specimen size.

关键词： Bicrystal Micropillar Twin boundary schmid factors size effect