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Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 391-398页

作者： S.j. Yao L.x. Du x.H. Liu G.D. wang State Key Laboratory ofRolling and Automation Northeastern University Shenyang 110004 China

Three warm-rolled ferrite/pearlite microstructures were prepared by rolling at 500℃, and the austenitizing characteristics were discussed in conjunction with deformation during the heating stage. The results indicated that the final austenite grain size was sensitive to the deformation direction of the initial warm-rolled microstructure. The transient microstructure at a given temperature was the most important influencing factor on the austenitizing characteristic combined with deformation. Moreover, the hot-rolled mierostructure also had to be prepared in an optimal state because of its direct effect on the warm-rolled microstructure.

关键词： Warm-rolled ferrite/pearlite Austenite Deformation Recrystallization

Dynamic Behavior of Bubble Interface During Boiling

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journal of Thermal Science 2002年第4期11卷 308-319页

作者： x.F.Peng Z.wang D.j.Lee Department of Thermal Engineering Tsinghua UniversityDepartment of Thermal Engineering Tsinghua UniversityDepartment of Chemical Engineering Taiwan University Beijing 100084 China Beijing 100084 China Taipei 106 China

A brief review with discussions is conducted for some pertinent works, done and ongoing in the Laboratory of Phase-Change and Interfacial Phenomena at Tsinghua University, on interfacial behavior of vapor bubbles and interfacial transport phenomena during liquid nucleation boiling. From a sequence of experimental investigations, some new phenomena, particularly, the visually observed interfacial transport phenomena or processes including jet-like flows, bubble interaction and spatial scale effect, were described in this article. The interfacial effects and transport phenomena associated with surface tension gradients caused by temperature and concentration variations were theoretically analyzed to reveal the marked influence on bubble interfacial shape and dynamic behavior, the bubble dynamics including nucleation, bubble motion and coalescence. Several theoretical models and methods were proposed to describe the dynamic characteristics and explain the physics of interfacial phenomena/processes. The

关键词： boiling interfacial phenomena transport process phase change bubble.

A Quantitative Analysis of Mn Segregation at Partitioned Ferrite/Austenite Interface in a Fe-C-Mn-Si Alloy

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journal of Materials Science & Technology 2009年第3期25卷 383-388页

作者： H. Guo S.W. Yang C.j.Shang x.M. wang x.L. He Department of Materials Physics and Chemistry University of Science and Technology Beijing Beijing 100083 China

Mn segregation at austenite/ferrite interface is studied in a Fe-C-Mn-Si alloy held at 656℃. Mn is partitioned during the growth of ferrite and as a result, a Mn pile-up exists in front of interface on the matrix side. An approach to evaluate Mn segregation quantitatively is developed by combining STEM raster window scanning and simulation of the interaction of the electron beam with the sample to subtract the contribution of Mn pile-up and obtain pure Mn segregation value. The evaluated maximum Mn interfacial segregation is in the order of a half-monolayer.

关键词： Interfacial segregation Phase transformation STEM Beam broadening

Effect of rolling ratios on the microstructural evolution and corrosion performance of an as-rolled Mg-8wt.%Li alloy

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journal of Magnesium and Alloys 2021年第2期9卷 560-568页

作者： B.j.wang D.K.xu x.Cai Y.x.Qiao L.Y.Sheng School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiangChina Peking University Shenzhen InstituteShenzhen Key Lab Human Tissue Regenerate&RepairShenzhen 518057China

In this work,the influence of rolling ratios on microstructural changes and corrosion behavior of an as-rolled Mg-8 wt.%Li alloy in0.1 mol/L Na Cl solution has been *** revealed that with the rolling ratio being increased from 3 to 10,theα-Mg phases were elongated and fragmented,whilst the area fraction of exposedβ-Li phases ***,the corrosion performance of the alloy decreased with the increased rolling *** all the samples,their corrosion processes were quite similar and can have two *** the initial stage with the samples being immersed for less than 6 h,the corrosion mainly occurred inβ-Li *** the samples were immersed for longer than 6 h,the corrosion attack transferred toα-Mg phases and the hydrogen evolution rate was accelerated.

关键词： Mg-li alloys Wrought Microstructure Corrosion performance

Construction of hybrid Z-scheme graphitic C_(3)N_(4)/reduced TiO_(2) microsphere with visible-light-driven photocatalytic activity

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journal of Materiomics 2018年第3期4卷 238-246页

作者： C.Zhou N.F.Ye x.H.Yan j.j.wang j.M.Pan D.F.wang Q.wang j.x.Zu x.N.Cheng School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013JiangsuChina Institute for Advanced Materials Jiangsu UniversityZhenjiang212013JiangsuChina Institute of Green Materials and Metallurgy Jiangsu UniversityZhenjiang 212013JiangsuChina

A novel Z-scheme graphitic C_(3)N_(4)/reduced TiO_(2)microsphere(g-C_(3)N_(4)/r-TiO_(2))has been successfully synthesized by a solvothermal *** as-prepared samples with different contents of g-C_(3)N_(4)were characterized by x-ray diffraction,electron paramagnetic resonance,scanning electron microscope,UV *** reflectance and photoluminescence *** r-TiO_(2)microspheres are aggregated on the surface of g-C_(3)N_(4)sheets in the as-prepared g-C_(3)N_(4)/r-TiO_(2)*** g-C_(3)N_(4)/r-TiO_(2)catalysts show enhanced photocatalytic activity for the degradation of rhodamine B under visible light *** could be attributed to these influences of oxygen vacancy(changing the band gap of TiO_(2)),the large specific surface area(providing much more active sites for photocatalytic reaction),and the synergetic effect between g-C_(3)N_(4)and r-TiO_(2)(promoting the separation for photoinduced electron-hole pairs).Moreover,the Z-scheme carriers transfer mechanism in the photocatalytic process has been discussed through trapping experiments of active *** work demonstrates the strategies of the construction of Z-scheme carriers transfer system,the introduction of oxygen vacancy and structure designing are beneficial to design materials toward solar energy conversion like contaminant degradation.

关键词： TiO_(2) C_(3)N_(4) Oxygen vacancy Z-scheme heterojunction Photocatalytic performance

Multistage serrated flow behavior of a medium-manganese high-carbon steel

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journal of Iron and Steel Research International 2020年第9期27卷 1064-1072页

作者： j.Chen Y.Zhang j.j.wang C.M.Liu S.x.Zhao Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819LiaoningChina Shenyang Industrial Transformation Upgrading Promotion Center Shenyang 110083LiaoningChina The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina School of Materials Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Central Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai 201999China

The deformation mechanisms and the flow stress behavior of a medium-manganese high-carbon steel during cold deformation at a strain rate of 10×5 s^-1 were explored using a universal testing machine,an x-ray diffractometer,a field emission scanning electron microscope and a high-resolution transmission electron *** results show that continuous step-up serrated flow behavior appears after the yielding point,and the true stress-strain curve is roughly divided into five stages based on distinctive densities and amplitudes of *** strengthening mechanisms of the experimental steel involve Cottrell atmosphere,twinning-induced plasticity(TWIP)efect and transformation-induced plasticity(TRIP)*** effect is the dominant deformation mechanism,and deformation twins formed by TWIP effect comprise primary,secondary and ***,TRIP effect arises in the local high-strain *** element plays a key role in the transformation of the deformation mechanism.A small amount of carbide precipitates around twin boundaries lead to the formation of local carbon-poor regions,and Md temperature and stacking fault energy of medium-manganese high-carbon steel are propitious to the occurrence of TRIP *** addition,the contributions of various deformation mechanisms to plasticity are calculated,and that of TWIP effect is the greatest.

关键词： Serrated flow Deformation mechanism Deformation twin Twinning-induced plasticity Transformation-induced plasticity

HExAHEDRAL ELEMENT REFINEMENT FOR THE PREDICTION- CORRECTION ALE FEM SIMULATION OF 3D BULKINGFORMING PROCESS

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Acta Metallurgica Sinica(English Letters) 2004年第6期17卷 923-927页

作者： j.Chen Y.x.wang W.P.Dong x.Y.Ruan DepartmentofPlasticityEngineering ShanghaiJiaotongUniversityShanghai200030China

Based on the characteristics of 3D bulk forming process, the arbitrary Lagrangian-Eulerian (ALE) formulation-based FEM is studied, and a prediction-correction ALE-based FEM is proposed which integrates the advantages of precisely predicting the boundary configuration of the deformed material, and of efficiently avoiding hexahedron remeshing processes. The key idea of the prediction-correction ALE FEM is elaborated in detail. Accordingly, the strategy of mesh quality control, one of the key enabling techniques for the 3D bulk forming process numerical simulation by the prediction-correction ALE FEM is carefully investigated, and the algorithm for hexahedral element refinement is formulated based on the mesh distortion energy.

关键词： prediction-correction ALE FEM 3D bulk forming numerical simulation hexahedron mesh refinement

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

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journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： jin-Peng wang Guo-Cui Mao Hui-Lin jiang Bao-xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

Seasonal dependency of controlling factors on the phytoplankton production in Taihu Lake, China

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journal of Environmental Sciences 2019年第2期31卷 278-288页

作者： Qiaohua Zhao jing wang jianjian wang julian x.L.wang College of Hydrometeorology Nanjing University of Information Science and Technology Air Resources Laboratory National Oceanic and Atmospheric AdministrationCollege Park

In this study, 44 profiles of gross primary productivity(GPP) and sunlight, along with water temperature, Chlorophyll-a(Chla) and nutrients, were observed in Meiliang Bay of Taihu Lake, China, in the spring, summer, and fall seasons. Effects of water temperature, light,and nutrient concentration were examined in relation to the GPP-unit-Chla(GPP of algae per Chla). The results showed that the optimum temperature for the GPP of phytoplankton was 27.9°C, the optimal PNA-unit-Chla(photon number absorbed by phytoplankton per Chla) was 0.25(mol), and the HSCN-unit-Chla and HSCP-unit-Chla(half-saturation constants of nitrogen and phosphorus of algae per Chla) were 0.005(mg/L) and 0.0004(mg/L), respectively. The seasonal dependency of the effect of different factors on the GPP was analyzed. Compared with temperature and nutrients, light was found to be the most important factor affecting the GPP during the three seasons. The effect of temperature and nutrients on the GPP of phytoplankton has obvious seasonal change. In spring, temperature was the secondary factor affecting the GPP of phytoplankton, and the effect of nutrients may be negligible in the eutrophic lake on account of temperature limit, which showed that the GPP of algae was only affected by the physical process. In summer and fall, temperature didn't affect the GPP of algae, and the presence of nutrients was the secondary factor affecting the GPP of phytoplankton. From summer to fall, effect of phosphorus was weakened and effect of nitrogen was enhanced.

关键词： Temperature limited effect Gross primary productivity Eutrophication Light limit Optimum temperature Half-saturation constants

Improvement of Appearance Traits of elite Rice Zhenshan 97B by Molecular Introgression of Targeted about 800 kb Interval from Indica Rice jiafuzhan Genome

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分子植物育种 2007年第2期5卷 209-210页

作者： x.j. Fang　 L.R. jiang Hainan Institute of Tropical Agricultural Resource Sanya 572025 China Life College Xiamen University Xiamen 361005 Fujian China.

Rice appearance trait is mainly mean grain length （GL）, grain width （GW）, ratio of length and width （L/W）, chalkiness （CH） and transparence （TR）. Appearance is the first impression, and rice appearance traits effect significantly the value of commodity. Hybrid rice is relatively low quality, especially on rice appearance quality, which restricts partially its extend and badly export of hybrid seed and rice in China. Shanyou 63, the most famous hybrid rice combination of China, could not be also sustainable application because of its poor qualities. In this studies, We attempt to improve appearance quality of the elite rice maintainer of Zhenshan 97B by using molecular approach of genomic interval targeted introgression. Three F2 populations were constructed to study the classical and molecular genetic of rice appearance traits, at the same time, molecular marker-asisted toimprove the main maintainer line, Zhenshan 97B were performed. There some following results： Three F2 populations were constructed based on crosses of Guangluai 4×jiafuzhan （Gj popu.）, Minghui 86×jiafuzhan （Mj popu.） and Zhenshan 97B×jiafuzhan （Zj popu.）. Zj popu and Gj popu were produced to reconstruct the linkage maps related with rice appearance traits based on BSA, and detect QTL of target traits based on IM. In Zj popu, 9 QTLs of target traits were detected. The interval, RM169-RMS16 on Chromosome 5, was genetic locus of GW, L/W, CH and BW, and the explained variances were 10.9%, 14.9%, 12.0% and 14.2%, respectively. RM214 on chromosome 7, RM339 on chromosome 8 were genetic loci ifCH and BW, and the explained variances were 9.4%, 10.0%, 11.0% and 12.1%. besides there is a genetic locus, RM347, of G/W on chromosome 3, and the explained varance was 10.3%. In Gj popu, 5 QTLs office appearance traits were detected. The interval, RM169- RM516 on Chromosome 5, were also the genetic loci of GW, CH and BW, and the explained variances were 9.0%, 12.5%, and 13.6%, respectively. RM264-RM80 on chromosom

关键词：外貌特征稻子分子育种基因表达