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journal of Materials Science & Technology 2021年第2期61卷 16-24页

作者： H.Niu H.C.jiang M.j.Zhao l.j.Rong CAS Key laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of ScienceShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China

NiTi/Stainless Steel(SS) sheets have been welded via a vacuum electron beam welding process, with three methods(offsetting electron beam to SS side without interlayer, adding Ni interlayer and adding Fe Ni interlayer), to promote mechanical properties of the Ni Ti/SS joints. The joints with different interlayers are all fractured in the weld zone near the Ni Ti side, which is attributed to the enrichment of intermetallic compounds including Fe2 Ti and Ni3 Ti. The fracture mechanisms of different joints are strongly dependent on the types of interlayers, and the joints without interlayer, adding Ni interlayer and adding Fe Ni interlayer exhibit cleavage fracture, intergranular fracture and mixed fracture composed of cleavage and tearing ridge, respectively. Compared with the brittle laves phase Fe2 Ti, Ni3 Ti phase can exhibit certain plasticity, block the crack propagation and change the direction of crack propagation. The composite structure of Ni3 Ti and Fe2 Ti will be formed when the Fe Ni alloy is taken as the interlayer, which provides the joint excellent mechanical properties, with rupture strength of 343 MPa.

关键词： NiTi Stainless steel Electron beam welding Interlayer Mechanical property

Reply to the note by li Piani et al.

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Defence Technology（防务技术） 2024年第1期31卷 603-606页

作者： T.li Piani j.Weerheijm l.j.Sluys TU Delft Stevinweg 12628 CNDelftthe Netherlands TNO PO Box 452280 AARijswijkthe Netherlands NlDA Faculty of Military Sciences1781 CADen Helderthe Netherlands

In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of *** opportunity for a new model in the field revealed from the observation that two older models recently used by the authors of Ref.[2] shared a linear relationship between the penetration depth P and the impacting velocity v_(O).

关键词： Penetration Adobe Modeling

A MICROMECHANICAl MODEl FOR γ-TiAl BASE PST CRYSTAlS

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Acta Metallurgica Sinica(English letters) 2005年第6期18卷 686-694页

作者： j.l. Su G.K. Hu School of Mechanics-Electrics Engineering Fujian Agriculture and Forestry University Fuzhou 350002 China Department of Applied Mechanics Beijing Institute of Technology Beijing 100081 China

An analytical micromechanical method is proposed to examine the dependence of plastic deformation on the microstructure for a PST crystal. The sub-domain microstructure of the γ phase and the effect of the α2 phase are taken into account by a proper micromechanical formulation, the dislocation slip and twinning deformation mechanisms are considered in the context of crystal plasticity. The model can well predict the dependence of stress-strain relations on loading angle with respect to the microstructure. The influence of the twinning and lamellar spacing on the deformation behavior and biaxial yield surfaces for PST crystals are also examined.

关键词： TiAI alloy crystal plasticity micromechanical model yield surface

Effect and mechanism of coking residual ammonia water treating by flue gas

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journal of Environmental Sciences 2001年第2期13卷 237-246页

作者： Z j Cheng G j Yin l Q Yang W Wang D D Cheng Environmental Protection Research Institute Central Research Institute of Building and Construction Ministry of Metallurgical Industry Beijing 100088 China.

The treatment of coking residual ammonia water has been a big difficult problem at home and abroad, and there is no breakthrough research achievement in the past. The invention patent "The method of treating all coking wastewater or treating coking residual ammonia water by flue gas" has been successfully used in Huaian Steel Works for high concentration and organic industry wastewater treatment. Not only can it realize the wastewater zero discharge, but also the wastewater treatment has an effect of de-sulfur and de-nitrogen for flue gas. So that the flue gas exhaust can meet the requirement of emission standard. The mass transfer and heat transfer, fly ash absorption and coagulation, acid and alkali neutralization reaction, catalysis oxidation and reduction reaction in flue gas would be the major factors.

关键词： Effect and mechanism of coking residual ammonia water

DOCK8 regulates signal transduction events to control immunity

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Cellular & Molecular Immunology 2017年第5期14卷 406-411页

作者： Conor j Kearney Katrina l Randall jane Oliaro Immune Defence laboratory Cancer Immunology Division The Peter MacCallum Cancer Centre East Melbourne Victoria 3002 Australia Sir Peter MacCallum Department of Oncology The University of Melbourne Parkville Victoria 3052 Australia Department of Immunology and Infectious Disease The John Curtin School of Medical Research Australian National University Acton Australian Capital Territory 2601 Australia Australian National University Medical School Australian National University Acton Australian Capital Territory 2605 Australia

Genetic mutations in the gene encoding DOCK8 cause an autosomal recessive form of hyper immunoglobulin E syndrome （AR-HIES）, referred to as DOCK8 deficiency. DOCK8 deficiency in humans results in the onset of combined immunodeficiency disease （CID）, clinically associated with chronic infections with diverse microbial pathogens, and a predisposition to malignancy. It is now becoming clear that DOCK8 regulates the function of diverse immune cell sub-types, particularly lymphocytes, to drive both innate and adaptive immune responses. Early studies demonstrated that DOCK8 is required for lymphocyte survival, migration and immune synapse formation, which translates to poor pathogen control in the absence of DOCK8. However, more recent advances have pointed to a crucial role for DOCK8 in regulating the signal transduction events that control transcriptional activity, cytokine production and functional polarization of immune cells. Here, we summarize recent advances in our understanding of DOCK8 function, paying particular attention to an emerging role as a signaling intermediate to promote immune responses to diverse external stimuli.

关键词： DOCK8 immunodeficiency lymphocytes NK Cells signal transduction

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维普期刊数据库评论

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Chinese Annals of Mathematics,Series B 2002年第2期23卷 293-310页

作者： j.l.VZQUEZ E.ZUAZUA Departamento de Matematicas Universidad AutonomaDepartamento de Matematica AplicadaUniversidadComplutense 28049MadridSpain28040 M

The authors study the asymptotic behaviour of solutions of the heat equation and a number of evolution equations using scaling techniques. It is proved that in the framework of bounded data stabilization need not occur and the general asymptotic behaviour is complex. This behaviour reflects for large times, even on compact sets, the complexity of the initial data at infinity.

关键词： Asymptotic behaviour Scaling Omega-limit Heat equation Hyperbolic conservation laws

A NOVEl METHOD FOR EVAlUATING PlANE STRESS DYNAMIC FRACTURE TOUGHNESS OF 0Cr18Ni10Ti STAINlESS STEEl WElDED jOINTS

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Acta Metallurgica Sinica(English letters) 2008年第4期21卷 303-312页

作者： Z.j. Xu Y.l. li School of Aeronautics Northwestern Polytechnical University Xi＇an 710072 China

A novel method was proposed for the evaluation of Mode I dynamic fracture toughness （DFT） under plane stress and small scale yielding conditions for welded joints of stainless steel （SS）, 0Cr18Ni10Ti. In a hybrid experimental-numerical approach, the experiments were carried out on the Hopkinson pressure bar apparatus, and three dimensional （3D） transient numerical simulations were performed by a finite element （FE） computer program. Macroscopical plastic deformation was observed at the loading and supporting points, on the specimens, after the test, which could cause a large error if omitted in the numerical simulation. Therefore, elustic-viscoplustic analysis was performed on the specimen by adopting the johnson-Cook （j-C） model to describe the rate-dependent plastic flow behavior of the material. The material heterogeneity in the mismatched welded joints, induced by the difference in the base metal （BM） and the weld metal （WM） in yield stress, has also been taken into consideration by using the j-C models separately. Good accordance was obtained between the experimental and the computational results by the present approach. The relationship between plane stress DFT and loading rate was also obtained on the order of 108 MPa.m^1/2.s^-1.

关键词： 0Cr18Ni10Ti Welded joint High strain rate Dynamic fracture Plane stress

An ensemble method for gene discovery based on DNA microarray data

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Science China(life Sciences) 2004年第5期47卷 396-405页

作者： Kathy l. MOSER Eric j. TOPOl Department of Medicine Institute of Human Genetics University of Minnesota Minnesota 55455 USA Center for Cardiovascular Genetics Department of Cardiovascular Medicine the Cleveland Clinic Foundation 9500 Euclid Avenue Cleveland Ohio 44195 USADepartment of Molecular Cardiology the Cleveland Clinic Foundation 9500 Euclid Avenue Cleveland Ohio 44195 USA

The advent of DNA microarray technology has offered the promise of casting new insights onto deciphering secrets of life by monitoring activities of thousands of genes simulta-neously. Current analyses of microarray data focus on precise classification of biological types, for example, tumor versus normal tissues. A further scientific challenging task is to extract dis-ease-relevant genes from the bewildering amounts of raw data, which is one of the most critical themes in the post-genomic era, but it is generally ignored due to lack of an efficient approach. In this paper, we present a novel ensemble method for gene extraction that can be tailored to fulfill multiple biological tasks including (i) precise classification of biological types; (ii) disease gene mining; and (iii) target-driven gene networking. We also give a numerical application for (i) and (ii) using a public microarrary data set and set aside a separate paper to address (iii).

关键词： microarrays,ensemble decision,recursive partition tree,feature gene selection.

Existence and Uniqueness of Fixed Point in Partially Ordered Sets and Applications to Ordinary Differential Equations

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2205-2212页

作者： juan j.NIETO RosanaRODRGUEZ-lPEZ Departamento de Análisis Matemático Facultad de MatemáticasUniversidad de Santiago de Compostela

We prove some fixed point theorems in partially ordered sets, providing an extension of the Banach contractive mapping theorem. Having studied previously the nondecreasing case, we consider in this paper nonincreasing mappings as well as non monotone mappings. We also present some applications to first-order ordinary differential equations with periodic boundary conditions, proving the existence of a unique solution admitting the existence of a lower solution.

关键词： fixed point partially ordered set first-order differential equation lower and upper solutions

Potential influence of wildfire in modulating climate-induced forest redistribution in a central Rocky Mountain landscape

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Ecological Processes 2017年第1期6卷 52-68页

作者： john l.Campbell Douglas j.Shinneman Department of Forest Ecosystems and Society Oregon State UniversityCorvallisORUSA U.S.Geological Survey Forest and Rangeland Ecosystem Science CenterBoiseIDUSA.

Introduction:Climate change is expected to impose significant tension on the geographic distribution of tree ***,tree species range shifts may be delayed by their long life spans,capacity to withstand long periods of physiological stress,and dispersal *** could theoretically break this biological inertia by killing forest canopies and facilitating species redistribution under changing *** investigated the capacity of wildfire to modulate climate-induced tree redistribution across a montane landscape in the central Rocky Mountains under three climate scenarios(contemporary and two warmer future climates)and three wildfire scenarios(representing historical,suppressed,and future fire regimes).Methods:Distributions of four common tree species were projected over 90 years by pairing a climate niche model with a forest landscape simulation model that simulates species dispersal,establishment,and mortality under alternative disturbance regimes and climate ***:Three species(Douglas-fir,lodgepole pine,subalpine fir)declined in abundance over time,due to climate-driven contraction in area suitable for establishment,while one species(ponderosa pine)was unable to exploit climate-driven expansion of area suitable for *** fire frequency accelerated declines in area occupied by Douglas-fir,lodgepole pine,and subalpine fir,and it maintained local abundance but not range expansion of ponderosa ***:Wildfire may play a larger role in eliminating these conifer species along trailing edges of their distributions than facilitating establishment along leading edges,in part due to dispersal limitations and interspecific competition,and future populations may increasingly depend on persistence in locations unfavorable for their establishment.

关键词： Forest disturbance Wildfire Climate change Central Rocky Mountains Climate niche Species migration Species distribution