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应用波束形成法研究51CrV4梯度功能钢的微观结构

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冶金分析 2009年第4期29卷 7-13页

作者： J. Goken M. Maikranz-Valentin J. Timmerberg s. Luker d. Fuβ J. Feierabend K. steinhoff . Institute of Maritime studies University of Applied Sciences Bergmannstr. 36 26789 Leer Germany Chair of Metal Forming Technology University of Kassel Kurt-Wolters-Str. 3 34125 Kassel Germany department of Electrical Engineering University of Applied Sciences Friedrich Paffrath-Str. 101 26389Wilhelmshaven Germany Agency of Computer-Generated Imagery Brahmsweg 2 49681 Garrel Germany Gfai Tech GmbH Rudower Chaussee 30 12489 Berlin Germany

对组分梯度功能范围的调整要求已提出,通常通过不同材料组合得以解决。但是这种生产方式一方面需要一系列的工序,另一方面也需要具体的知识,包括所用材料的独特物理及机械特性,尤其是它们的形变及热行为。因此,为了降低能耗,考虑到生态... 详细信息

对组分梯度功能范围的调整要求已提出,通常通过不同材料组合得以解决。但是这种生产方式一方面需要一系列的工序,另一方面也需要具体的知识,包括所用材料的独特物理及机械特性,尤其是它们的形变及热行为。因此,为了降低能耗,考虑到生态需求,一个组分的现代工业设计程序只应包括一种操作程序和一种具有优化性能的范围大的材料。同时对同质的工件初样进行热处理及机械处理保证了控制材料能够具有最终元件性能的梯度功能。第一步,研究不同热处理对CrV-合金热处理矩形条钢(51CrV4)微观结构演化的影响。生产出只具有铁素体-珠光体、铁素体-珠光体-贝氏体和马氏体结构的条钢。与振动的振幅衰减相关的时间由声学照相机测定。这种声学照相机可以产生彩码声音图谱,显示覆盖于已记录样品图像上噪音的强度和来源。基于作为常规信号处理方法的波束形成概念,该声音分析用来控制换能器阵列上信号的接收或传播方向。条钢的独特微观结构状况造成了振动特性的显著变化。

关键词：钢梯度功能内耗波束形成法

Effect of different starting materials on the synthesis of Ba_(0.8)Ca_(0.2)TiO_(3)

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Journal of Advanced Ceramics 2015年第1期4卷 65-70页

作者： P.N.MEdEIROs V.d.ARAÚJO A.P.A.MARQUEs R.L.TRANQUILIN C.A.PAsKOCIMAs M.R.d.BOMIO J.A.VARELA E.LONGO F.V.MOTTA dEMAT CTUFRNAv.Sen.Salgado Filho3000CEP 59072-970 NatalRNBrazil UACsA UFRPEBR 101 Sul5225CEP 54510-000 Cabo de Santo AgostinhoPEBrazil UNIFEsP Rua Prof.Artur Riedel275CEP 09972-270 DiademaSPBrazil dLIECIQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazil LIEC IQUNESPRua Francisco Degni s/nCEP 14801-907 AraraquaraSPBrazi

Literature has reported the synthesis of barium calcium titanates by various synthesis methods such as solid state reaction,co-precipitation and polymer *** compounds are usually obtained using calcium carbonate(CaCO_(3)),barium carbonate(BaCO3)and titanium oxide as starting *** study investigated the effect of different starting reagents on the synthesis of Ba_(0.8)Ca_(0.2)TiO_(3)(BCT)by complex polymerization method(CPM).Two sets of starting precursors were used:titanium citrate,CaCO_(3)and BaCO3,and titanium citrate and Ba1-xCaxCO3 solid solution *** were crystallized at a temperature range from 400℃to 700℃for different *** obtained powders were characterized by X-ray diffraction(XRd),thermogravimetry(TG)and differential thermal analysis(dTA),and Raman and infrared *** infrared spectroscopy indicated that the chelation processes of Ba,Ca,Ti and CA ions are very *** results showed that the use of CaCO_(3)and BaCO3 or Ba1-xCaxCO3 solid solution as precursors does not affect the final properties of BCT powders obtained by CPM.

关键词： ceramic synthesis Ba_(0.8)Ca_(0.2)TiO_(3)(BCT) complex polymerization method(CPM)

REsEARCH OF THE FEEdING sPEEd AdOPTING COREd-WIRE METHOd TO sPHEROIdIZE dUCTILE IRON MELT

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Acta Metallurgica sinica(English Letters) 2008年第5期21卷 362-368页

作者： G.W. Chang H.X. Wang X.d. Yue H.L. Zhang school of Materials and Chemical Engineering Liaoning University of Technology Jinzhou 121001 China Mechanical and Electronic Engineering department West Anhui University Liu＇an 237012 China Baotou Wen Xin Industry Limited Company Baotou 014000 China Manuscript received 29 August 2007

For settling the question of feeding speed in applying the cored-wire method to spheroidize ductile iron melt, ANsYs software was applied to simulate the heat transfer and mass transfer, and the melt time of the steel strip in the iron melt was determined by linking the heat transfer and mass transfer, and then the feeding speed was calcufated. Conclusions have been drawn that the iron layer was formed on the surface of the cored-wire during the wire-feeding process. The thickness is 0.073 mm when the temperature of the iron melt is 1500℃, the time from formation to remelting of the iron layer is 0.063 s. When the temperature of the iron melt is below 1500℃, the time taken for the steel strip to melt is rapidly shortened. When the temperature of the iron melt is above 1500℃, the variation amplitude of the steel strip melt change with time is gradually diminished. The melt time of the steel strip is rapidly increased with the increase of the steel strip thickness. When the temperature of the iron melt is 1500℃ and the carbon content is 4%, the melt time of a steel strip, which has a thickness of 0.5 mm, is thrice that of a steel strip whose thickness is 0.3 mm. The calculation results of the feeding speed are basically in agreement with the applied feeding speed in the factory.

关键词： ductile iron spheroidize Feeding speed Numerical simulation

Re-folded structure of syn-orogenic granitoids(Padrón dome, NW Iberia):Assessing rheological evolution of cooling continental crust in a collisional setting

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Geoscience Frontiers 2019年第2期10卷 651-669页

作者： Rubén díez Fernández Francisco J.Rubio Pascual Luis Miguel Martín Parra departamento de Geodinámica Estratigrafía y PaleontologíaFacultad de Ciencias GeológicasUniversidad Complutense de Madrid Instituto Geológico y Minero de Espana

This contribution discusses about the rheological, kinematic and dynamic frameworks necessary to produce recumbent and upright folds from syn-orogenic granitic massifs that were formed during an early stage of magma genesis related to the onset of a migmatitic dome. syn-kinematic granitoids occurring within the high-grade infrastructure of the Padron migmatitic dome(NW Iberia) are deformed into largescale recumbent folds(d_2) that are later affected by upright folds(d_3). Petrostructural analysis of a selected area of this dome reveals that after a period of crustal thickening(d_1), NNW-directed extensional flow gave way to recumbent folds and penetrative axial plane foliation(s_2). superimposed subhorizontal compression resulted in upright folds(d_3). A closer view into the dynamics of the dome allows exploring the factors that may condition the nucleation of folds with contrasting geometries during progressive deformation of molten continental crust. The formation of folds affecting syn-kinematic granitoids suggests a cooling metamorphic path in migmatitic domes. Active and passive folding mechanisms require a crystallizing(cooling) magma to nucleate folds. A more competent metamorphic host inhibits fold nucleation from much less competent magmas. As it crystallizes, magma becomes more rigid(competent),and approaches viscosity values of its host. Passive folding is favored when no significant competence contrast exists between magma and host, so this folding mechanism is more likely shortly after magma genesis and emplacement. In such conditions, and under dominant subhorizontal flow accompanied by flattening(d_2),passive folding would produce isoclinal recumbent geometries. Further magma cooling introduces a shift into the rheological behavior of partially molten crust. Thereon, crystallizing magma bodies would represent significant competence contrasts relative to their host. At this point, buckling is a more likely folding mechanism, and more regular, buckle fo

关键词： Recumbent folds Migmatitic domes Partial melting Crustal-derived granitoids Orogenic collapse Variscan orogen

Cell-specific pathways recruited for symbiotic nodulation in the Medicago truncatula legume

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Molecular Plant 2022年第12期15卷 1868-1888页

作者： sergio Alan Cervantes-Pérez sandra Thibivilliers Carole Laffont Andrew d.Farmer Florian Frugier Marc Libault department of Agronomy and Horticulture Center for Plant Science InnovationUniversity of Nebraska-LincolnLincolnNE 68503USA single Cell Genomics Core Facility Center for BiotechnologyUniversity of Nebraska-LincolnLincolnNE 68588USA Institute of Plant sciences Paris-saclay(IPs2) UniversitéParis-SaclayCNRSINRAEUniversitéParis-CitéUniversitéd’Evry91190 Gif-sur-YvetteFrance National Center for Genome Resources Santa FeNM 87505USA

Medicago truncatula is a model legume species that has been studied for decades to understand the symbiotic relationship between legumes and soil bacteria collectively named *** symbiosis called nodulation is initiated in roots with the infection of root hair cells by the bacteria,as well as the initiation of nodule primordia from root cortical,endodermal,and pericycle cells,leading to the development of a new root organ,the nodule,where bacteria fix and assimilate the atmospheric dinitrogen for the benefit of the ***,we report the isolation and use of the nuclei from mock and rhizobia-inoculated roots for the single nuclei RNA-seq(sNucRNA-seq)profiling to gain a deeper understanding of early responses to rhizobial infection in Medicago roots.A gene expression map of the Medicago root was generated,comprising 25 clusters,which were annotated as specific cell types using 119 Medicago marker genes and orthologs to Arabidopsis cell-type marker genes.A focus on root hair,cortex,endodermis,and pericycle cell types,showing the strongest differential regulation in response to a short-term(48 h)rhizobium inoculation,revealed not only known genes and functional pathways,validating the sNucRNA-seq approach,but also numerous novel genes and pathways,allowing a comprehensive analysis of early root symbiotic responses at a cell type-specific level.

关键词： Medicago root single-cell transcriptomic rhizobium nodule initiation root hair cells cortical cells

Exploring the light-quark interaction

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Chinese Physics C 2009年第12期33卷 1189-1196页

作者：常雷 Ian C. CLOЁT Bruno El-BENNICH Thomas KLHN Craig d. ROBERTs Institute of Applied Physics and Computational Mathematics department of Physics University of Washington Seattle WA 98195 USA Physics division Argonne National Laboratory Argonne Illinois 60439 USA department of Physics Peking University

Two basic motivations for an upgraded JLab facility are the needs： to determine the essential nature of light-quark confinement and dynamical chiral symmetry breaking （dCsB）; and to understand nucleon structure and spectroscopy in terms of QCd＇s elementary degrees of freedom. during the next ten years a programme of experiment and theory will be conducted that can address these questions. We present a dyson- schwinger equation perspective on this effort with numerous illustrations, amongst them： an interpretation of string^breaking; a symmetry-preserving truncation for mesons; the nucleon＇s strangeness σ-term; and the neutron＇s charge distribution.

关键词： Bethe-salpeter equations bound-states confinement dynamical chiral symmetry breaking,dyson-schwinger equations Faddeev equation nucleon electromagnetic form factors

Protective effects of anti-ricin A-chain RNA aptamer against ricin toxicity

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World Journal of Gastroenterology 2008年第41期14卷 6360-6365页

作者： shaoan Fan Feng Wu Frank Martiniuk Martha L Hale Andrew d Ellington Kam-Meng Tchou-Wong department of Environmental Medicine New York University School of Medicine 57 Old Forge Road Tuxedo New York 10987 United States department of Medicine New York University School of Medicine 550 First Avenue New York 10016 United States Integrated Toxicology division U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) Fort Detrick Maryland 21702 United States department of Chemistry and Biochemistry University of Texas at Austin Austin Texas 78712 United States

AIM： To investigate the therapeutic potential of an RNA ligand （aptamer） specific for the catalytic ricin A-chain （RTA）, the protective effects of a 31-nucleo- tide RNA aptamer （31RA）, which formed a high affinity complex with RTA, against ricin-induced toxicity in cell- based luciferase translation and cell cytotoxicity assays were evaluated. METHOds： To test the therapeutic potential of anti- RTA aptamers in Chinese hamster ovary （CliO） AA8 cells stably transfected with a tetracycline regulatable promoter, ricin ribotoxicity was measured us- ing luciferase and ricin-induced cytotoxicity was ascertained by MTs cell proliferation assay with tet- razolium compound [3-（4,5-dimethylthiazol-2-yl）- 5-（3-carboxymethoxyphenyl）-2-（4-sulfophenyl）-2H- tetrazolium]. REsULTs： Inhibition of protein synthesis by ricin in CliO AA8 cells resulted in diminished luciferase activity and treatment with polyclonal antibody against degly- cosylated RTA （dgA） neutralized the inhibitory effects of ricin on luciferase activity and protected against ricin-induced cytotoxicity as measured by MTs assay. The 31RA anti-RTA aptamer inhibited the translation of luciferase mRNA in cell-free reticulocyte translation assay. 31RA aptamer also partially neutralized the inhibitory effects of ricin on luciferase activity and partially protected against ricin-induced cytotoxicity in CliO AA8 cells. CONCLUsION： We have shown that anti-RTA RNA aptamer can protect against ricin ribotoxicity in cell- based luciferase and cell cytotoxicity assays. Hence, RNA aptamer that inhibits RTA enzymatic activity represents a novel class of nucleic acid inhibitor that has the potential to be developed as a therapeutic agent for the treatment of ricin intoxication.

关键词： Ricin inhibitor RNA aptamer Luciferase assay

Phase transitions in(KNO3)1-x(NaNO2)x embedded into molecular sieves

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Phase transitions in(KNO3)1-x(NaNO2)x embedded into molecula...

Management of high-flow arteriovenous malformation in the maxillofacial region

第十届中俄双边新材料新工艺研讨会

作者： A.Yu.Milinskiy s.V.Baryshnikov E.V.Charnaya d.Michel Blagoveschensk state Pedagogical University Blagoveschensk675002 Russia Institute of Physics St.Petersburg State UniversitySt.PetersburgPetrodvorets198504 Russia Faculty of Physics and Geosciences University of LeipzigLeipzigD-04103 Germany

dielectric studies of molecular sieves MCM-41 filled with(KNO)(NaNO) salts(x=0,0.05,and 0.10) were examined and compared with results,obtained for their bulk *** regular increase upon warming in the temperature of the reconstructive phase transition from phaseⅡto phaseⅠwith decreasing pore sizes was observed for all x.A thermodynamic model for shifts of reconstructive phase transitions was *** persisted below room temperature in the bulk salts with x =0.05,0.10.

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Management of high-flow arteriovenous malformation in the ma...