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Journal of Materials Science & Technology 2012年第7期28卷 666-672页

作者： S.Q. Deng Z.P. Xue y.h. yang Q. yang y.L. Liu Department of Chemistry Jinan University Guangzhou 510632 China

Well dispersed and homogeneous y2O2S：Sm3＋ hollow submicrospheres were successfully achieved by a template- free solvothermal method combining with a postcalcining process. The crystalstructure and particle morphology were investigated by the X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） spectra, scanning and transmission electron microscopy （SEM and TEM）, respectively. A possible growth mechanism was proposed to reveal the formation process. Luminescence properties of the y202S：Sm3＋ long-lasting phosphor were an- alyzed by measuring the excitation spectra, emission spectra, afterglow decay curve and thermoluminescence curve. The excitation spectra indicated that the phosphor could be excited effectively by the ultraviolet-light emitting diode （UV-LED） or blue LED, and the emission spectra showed that the phosphor could emit red light from 600 to 650 nm.

关键词： yttrium oxysulfide hollow submicrosphere Luminescence Long-lasting phosphor

EFFECT OF Zr ADDITION TO Ti-KILLED STEEL ON INCLUSION FORMATION AND MICROSTRUCTURAL EVOLUTION IN WELDING INDUCED COARSE-GRAINED hEAT AFFECTED ZONE

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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 220-226页

作者： F. Chai C.F. yang h. Su y.Q. Zhang Z. Xu y.h. yang Institute for Structural Materials Central Iron and Steel Research Institute Beijing 100081 China School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200030 China School of Materials Science and Engineering Kunming University of Science and Technology Kunming650093 China

Effects of Zirconium on the chemical component and size distribution of Ti-bearing inclusions, favored the grain refinement of the welding reduced, coarse-grained heat affected zone （CGhAZ） with enhanced impact toughness in Ti-killed steels, which were examined based on experimental observations and thermodynamic calculations. It indicated that the chemical constituents of inclusions gradually varied from the TiO oxide to the Ti-O＋Zr-O compound oxide and a single phase of the ZrO2 oxide, as the Zr content increased from zero to 0.0100%. A trace of Zr （0.0030%-0.0080%, depending on the oxygen content in liquid steel） provided a large amount of nucleating core for Ti oxide because of the larger specific density of ZrO2 oxide, and produced a small size distribution of the inclusions favorable for acicular ferrite transformation with a high nucleation rate in the CGhAZ, and a high volume fraction of acicular ferrite was obtained in the CGhAZ, with enhanced impact toughness. Otherwise, a high content of Zr （-0.0100%） produced a single phase Zr02, which was impotent to nucleate acicular ferrite, and a microstructure composed of ferrite side plate and grain boundary ferrite developed in the CGhAZ. The experimental results were confirmed by thermodynamic calculations.

关键词： Nonmetallic inclusions Zirconium Acicular ferrite Coarse-grain heat affected zone (CGhAZ)

CONSTITUTIVE RELATIONShIP OF IN718 ALLOy FOR ThERMOVISCOPLASTIC AND MICROSTRUCTURE EVOLUTION COUPLED ANALySIS

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Acta Metallurgica Sinica(English Letters) 2007年第5期20卷 373-379页

作者： D. Liu y.h. yang J. Geng Z.J. Luo School of Materials Science Northwestern Polytechnical University Xi＇an 710072 China

The interaction between thermomechanical parameters and microstructure evolution is so intense that it must be considered during the finite element method （FEM） simulation of the hot plastic working process, for materials that are difficult to deform. Taking the microstructure evolution into account, a novel type of constitutive relationship has been put forward for the IN718 alloy. The microstructure evolution model was first established for the dominant microstructure evolution processes. Then the microstructure evolution models and the method to determine the local flow stress of the corresponding microstructure for current thermomechanical parameters and deformation history were presented. Once the local flow stresses of different structures and their volume contributions were defined, the apparent flow stress of the material could be determined as the weighted sum of the local flow stresses and volume contributions. To validate the proposed method, a thermoviscoplastics and microstructure evolution coupled analysis for a forging process of a critical IN718 disk forging was performed. The predicting results were in close agreement with the experimental data.

关键词： constitutive relationship microstructure evolution numerical simulation IN718 alloy

MEChANICAL PROPERTIES OF LONGITUDINAL SUBMERGED ARC WELDED STEEL PIPES USED FOR GAS PIPELINE OF OFFShORE OIL

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Acta Metallurgica Sinica(English Letters) 2008年第2期21卷 85-93页

作者： Z.Z. yang W. Tian Q.R. Ma y.L. Li J.K. Li J.Z. Gao h.B. Zhang y.h. yang Tubular Goods Research Center of CNPC Xi＇an 710065 China Xiran Aerotechnical College Xi＇an 710077 China

Since the development of offshore oil and gas, increased submarine oil and gas pipelines were installed. All the early steel pipes of submarine pipelines depended on importing because of the strict requirements of comprehensive properties, such as, anti-corrosion, resistance to pressure and so on. To research and develop domes- tic steel pipes used for the submarine pipeline, the Longitudinal-seam Submerged Arc Welded （LSAW） pipes were made of steel plates cut from leveled hot rolled coils by both the JCOE and UOE （the forming process in which the plate like the letter “J”, “C”, “0” or “U” shape, then expansion） forming processes. Furthermore, the mechanical properties of the pipe base metal and weld metal were tested, and the results were in accordance with the corresponding pipe specification API SPEC 5L or DNV- OS-FI01, which showed that domestic LSAW pipes could be used for submarine oil and gas pipelines.

关键词： Mechanical properties Offshore oil and gas Longitudinal-seamsubmerged arc welded pipe (LSA W) Pipeline JCOE formingprocess UOE forming process

Improving Plant Transformation Using Zygote as the Recipient Cell

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分子植物育种 2007年第2期5卷 287-288页

作者： y.h. yang　 h.Q. Tian School of Life Sciences Xiamen University Xiamen 361005 China

Since the first transgenic plant was obtained from tobacco in the 1980's, the transformation of higher plants has been a vigorous field of study using applications of molecular biology. To date, transgenic methods of ... 详细信息

关键词：植物转换接合子受体细胞烟叶

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.y.h.ang Z.yang S.y.yang Z.h.Dai y.J.Liu J.h.Liao G.y.Zhong Z.J.Xie y.P.Fang S.S.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully.h.rnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly.h.gher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure heterostructure Photothermal effect Photocatalyst hydrogen evolution

Microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with different prestrain levels

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Journal of Materials Science & Technology 2024年第4期171卷 80-93页

作者： y.h.Zhang h.Li Z.W.yang X.Liu Q.F.Gu State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of high-Performance Precision Forming Technology and Equipment Northwestern Polytechnical UniversityXi’an 710072China

Ni_(47)Ti_(44)Nb_(9)shape memory alloy(SMA)is a promising material in the aerospace field due to its wide transformation *** application of shape memory effect depends on multistep thermomechan-ical loading,viz.,low-temperature deformation and subsequent heating to ***-temperature deformation prestrain plays a pivotal role in shape memory properties tailoring of SMA ***,microstructure evolution and deformation mechanisms of Ni_(47)Ti_(44)Nb_(9)SMA subjected to vari-ous prestrain levels are still *** this end,microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with prestrain levels of 8%-16%at-28℃(M_(s)+30℃)were *** results demonstrate that the stress-strain curve of the specimen exhibits four distinct stages at a maximal prestrain of 16%.Whereas stageⅡand stageⅢend at prestrains of∼8%and∼12%,*** stageⅡ,the stress-induced martensitic transformation is accompanied by the dislocation slip of the NiTi matrix andβ-Nb *** stageⅢ,in addition to the higher density of dislocations and further growth of stress-induced martensite variants(SIMVs),(001)compound twins are introduced as a result of the(001)deformation twinning in stress-induced ***{20-1}martensite twins are gradually introduced in stageⅣ.Correspondingly,after subsequent unloading and heating,a higher density of{114}austenite twins form in the specimen with a larger prestrain of 16%.With increasing prestrain from 8%to 16%,the recoverable strainε_(re)^(T)upon heating increases first and then ***ε_(re)^(T)obtains a maximum of 7.03%at 10%prestrain and de-creases to 6.17%at 16%*** increase ofε_(re)^(T)can be attributed to the formation of new SIMVs,the further growth of existing SIMVs,and the recoverable(001)compound *** the decrease ofε_(re)^(T)is mainly associated with the irrecoverable strain by{20−1}martensite *** effe

关键词： Ni_(47)Ti_(44)Nb_(9)shape memory alloy Wide transformation hysteresis Thermomechanical loading Microstructure evolution Shape memory behaviors Stress-induced martensitic transformation Deformation twinning

Morphology-Tailored Dynamic State Transition in Active-Passive Colloidal Assemblies

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Research 2024年第3期2024卷 751-760页

作者： Nan yu Zameer h.Shah Mingcheng yang yongxiang Gao Institute for Advanced Study Shenzhen University518060ShenzhenChina Key Laboratory of Optoelectronic Device and Systems of Ministry of Education and Guangdong Province College of Optoelectronic EngineeringShenzhen University518060ShenzhenChina Beijing National Laboratory for Condensed Matter Physics and Laboratory of Soft Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory DongguanGuangdong 523808China.

Mixtures of active self-propelled and passive colloidal particles promise rich assembly and dynamic states that are beyond reach via equilibrium ***,controllable transition between different dynamic states remains ***,we reveal a plethora of dynamic behaviors emerging in assemblies of chemically propelled snowman-like active colloids and passive spherical particles as the particle shape,size,and composition are *** example,assembles of one or more active colloids with one passive particle exhibit distinct translating or orbiting states while those composed of one active colloid with 2 passive particles display persistent“8”-like cyclic motion or hopping between circling states around one passive particle in the plane and around the waist of 2 passive ones out of the plane,controlled by the shape of the active colloid and the size of the passive particles,*** morphology-tailored dynamic transitions are in excellent agreement with state diagrams predicted by mesoscale dynamics *** work discloses new dynamic states and corresponding transition strategies,which promise new applications of active systems such as micromachines with functions that are otherwise impossible.

关键词： Transition otherwise transitions

Nitrogen-doping boosts *CO utilization and h2O activation on copper for improving CO2 reduction to C2+ products

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Green Energy & Environment 2024年第9期9卷 1459-1465页

作者： yisen yang Zhonghao Tan Jianling Zhang Jie yang Renjie Zhang Sha Wang yi Song Zhuizhui Su Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and Thermodynamics CAS Research/Education Center for Excellence in Molecular Sciences Center for Carbon Neutral Chemistry Institute of Chemistry Chinese Academy of Sciences School of Chemical Sciences University of Chinese Academy of Sciences Key Laboratory of Photochemistry CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

To improve the electrocatalytic transformation of carbon dioxide （CO2） to multi-carbon (C2+) products is of great *** we developed a nitrogen-doped Cu catalyst,by which the maximum C2+Faradaic efficiency can reach 72.7%in flow-cell system,with the partial current density reaching 0.62 A *** in situ Raman spectra demonstrate that the *CO adsorption can be strengthened on such a N-doped Cu catalyst,thus promoting the*CO utilization in the subsequent C–C coupling ***,the water activation can be well enhanced by N doping on Cu *** to the synergistic effects,the selectivity and activity for C2+products over the N-deoped Cu catalyst are much improved.

关键词： Electrocatalytic CO 2 reduction reaction Copper catalyst Doping Multi-carbon products In situ Raman measurement

Copper-catalyzed C(sp)-h aryl amination enables modular synthesis of quinolines and 2-quinolinones

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Science China Chemistry 2024年第2期67卷 595-603页

作者： yang Gao haixia Li Simin yang yanping huo Qian Chen Xianwei Li Zhe Wang Xiao-Qiang hu School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou510006China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory Jieyang515200China Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education&hubei Key Laboratory of Catalysis and Materials Science School of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhan430074China

herein,we disclose a novel copper-catalyzed C(sp)-h aryl amination of terminal alkynes with anthranils,enabling the rapid generation of highly reactive secondary N-aryl ynamines for the modular synthesis of structurally diverse C2-substituted quinolines and *** in-situ formed carbonyl-ynamines are prone to tautomerize to carbonyl-ketenimines,which can efficiently react with a series of nucleophiles,including amines,alcohols,phenols,thiols,thiophenols,active-methylene compounds,and even water to produce various quinoline derivatives with the generation of h_(2)O as a sole and green *** method also unlocks a practical route to create various quinoline-fused heterocycles and can be successfully applied to the late-stage modification of complex molecules and the concise synthesis of bioactive *** studies reveal a coppercatalyzed inner-sphere nitrene transfer process by using anthranils as novel aryl nitrene precursors.

关键词： copper catalysis anthranils C(sp)-h aryl amination carbonyl-ketenimines quinolines