检索结果-南通市图书馆

Journal of Materials Science & Technology 2011年第3期27卷 257-265页

作者： Fayun Lu ping yang Li Meng Fenge Cui Hua Ding School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China College of Materials and Metallurgy Northeastern University Shenyang 110004 China

Strain-induced martensites in high manganese TRIP/TWIP steels were investigated in the presence of thermal martensites and under the influence of austenitic grain orientation by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electron backscattered diffraction （EBSD）. Before deformation, the morphology of α＇- M depended mainly on the number of variants and growing period. Regardless of martensite morphologies and deformation, the Kurdjumov-Sachs （K-S） orientation relationships always maintained. The 6 α＇-M variants formed from a plate of ε-M were of 3 pairs of twins with a common axis 〈110〉α＇ parallel to the normal of {112}γ habit plane to minimize transformation strain. When α＇-M could be formed only by deformation, it nucleated at the intersection of ε-M variants and grew mainly in thick ε-M plates. Thick ε plates promoted significantly the α＇-M and weakened the influence of grain orientations. During tension, the transformation in 〈100〉-oriented grains was observed to be slower than that in 〈121〉-oriented grains. Deformation twins promoted ε-M formation slightly and had no apparent effect on α＇-M. Deformation increased the number of ε-M variants, but reduced that of α＇-M variants.

关键词： High manganese steel Martensite TRIP effect Orientation relationship Electron backscattered diffraction (EBSD)

Stereoselective Synthesis of syn- and anti-3a-Hydroxyl-1, 2, 3, 3a, 8, 8a-hexahydropyrrolo[2,3-b] indole-2-carboxylic Acid

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2003年第2期14卷 130-132页

作者： Xiao Yin yang Christian HAUG Yi ping yang Zhi Sheng HE yang YE State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaShanghai Institutes for Biological SciencesChinese Academy of ScienceShanghai 200031 Bicoll Biotechnology(Shanghai)Co.Ltd. 518A Bibo RoadShanghai 201203

The structure of syn- and anti-Nb-(p-toluenesulfonyl)-3a-hydroxyl-1, 2, 3, 3a, 8, 8a-hexahydro pyrrolo[2,3-b] indole-2-carboxylic t-butyl ester was stereoselectively synthesized by oxidative ring formation of Nb-(p-toluenesulfonyl)-L-tryptophan t-butyl ester in methylene chloride containing dimethyldioxirane (DMDO), the p-toluenesulfonyl group and t-butyl group can be easily removed by sodium naphthalenide and trifluoroacetic acid, respectively.

关键词： Oxidative ring formation Sodium naphthalenide Stereoselective synthesis

Effect of carbon solution-loss reaction on properties of coke in blast furnace

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2020年第5期27卷 489-499页

作者： Qi-hang Liu Shuang-ping yang Chen Wang Yi-long Ji School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055ShaanxiChina Metallurgical Engineering Technology Research Center of Shaanxi Province Xi’an 710055ShaanxiChina Anhui Province Key Laboratory of Metallurgical Engineering and Resources Recycling Anhui University of TechnologyMa’anshan 243002AnhuiChina

The pore structure of coke under CO2 atmosphere was investigated by the carbon solution-loss reaction *** results show that the pore size distribution of coke gradually changes from dispersion to relative concentration with the increase in carbon loss rate,but it tends to be dispersed again in the late stage of the reaction,and the pore volume and specific surface area also increase first and then decrease with the increase in carbon loss *** electron microscopy results show that the evolution of coke pores is from the formation of micropores to the expansion of micropores,and finally the micropore and mesopores collapse to form a large number of string *** chemical bonds and functional groups of different reacted cokes were analyzed by Fourier-transform infrared ***,the microstructure of reacted cokes was analyzed by optical microscopy,and then the ordering of the affinity of different microstructures with CO2 was *** volume hypothesis which was the theory about energy size of comminution was adopted to analyze the degradation behavior of reacted *** breakage energy of reacted cokes was calculated by volume hypothesis,and the power consumption coefficient CK of different reacted cokes was determined by drum experiment,and then the degradation behavior of reacted cokes under different power consumptions was predicted.

关键词： Coke property Carbon solution-loss reaction Coke degradation Coke pore Volume hypothesis Breakage energy

Quantitative evaluation of multi-process collaborative operation in steelmaking–continuous casting sections

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2021年第8期28卷 1353-1366页

作者： Jian-ping yang Qing Liu Wei-da Guo Jun-guo Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Engineering Research Center of MES Technology for Iron&Steel Production Ministry of EducationBeijing 100083China Laiwu iron and Steel Group Yinshan Section Steel Co. Ltd.Jinan 271104China Hesteel Group Tangsteel Company Tangshan 063000China

The quantitative evaluation of multi-process collaborative operation is of great significance for the improvement of production planning and scheduling in steelmaking–continuous casting sections(SCCSs). However, this evaluation is difficult since it relies on an in-depth understanding of the operating mechanism of SCCSs, and few existing methods can be used to conduct the evaluation, due to the lack of full-scale consideration of the multiple factors related to the production operation. In this study, three quantitative models were developed, and the multiprocess collaborative operation level was evaluated through the laminar-flow operation degree, the process matching degree, and the scheduling strategy availability degree. Based on the evaluation models for the laminar-flow operation and process matching levels, this study investigated the production status of two steelmaking plants, plants A and B, based on actual production data. The average laminar-flow operation(process matching) degrees of SCCSs were obtained as 0.638(0.610) and 1.000(0.759) for plants A and B, respectively, for the period of April to July 2019. Then, a scheduling strategy based on the optimization of the furnace-caster coordinating mode was suggested for plant A. Simulation experiments showed higher availability than the greedy-based and manual strategies. After the proposed scheduling strategy was applied,the average process matching degree of the SCCS of plant A increased by 4.6% for the period of September to November 2019. The multi-process collaborative operation level was improved with fewer adjustments and interruptions in casting.

关键词： steelmaking–continuous casting multi-process collaborative operation quantitative evaluation model laminar-flow operation process matching scheduling strategy

Magnetic Interactions with Strain Gradient in Ultrathin Pr_(0.67)Sr_(0.33)MnO_(3) Films

在线全文

学校读者我要写书评

暂无评论

Engineering 2024年第9期40卷 158-165页

作者： Bangmin Zhang ping yang Jun Ding Jingsheng Chen Gan Moog Chow Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices School of PhysicsSun Yat-sen UniversityGuangzhou 510275China Singapore Synchrotron Light Source National University of SingaporeSingapore 117603Singapore Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore

Strain gradient is a normal phenomenon around a heterostructural interface in ultrathin film,and it is important to determine its effect on magnetic interactions to understand interfacial *** this work,ultrathin Pr_(0.67)Sr_(0.33)MnO_(3)(PSMO)films on different substrates are *** PSMO film under different in-plane strain conditions,the saturated magnetization and Curie temperature can be qualitatively explained by double-exchange interaction and the Jahn-Teller ***,the difference in the saturated magnetization with zero field cooling and 5 T field cooling is proportional to the strain ***-gradient-induced structural disorder is proposed to enhance phonon-electron antiferromagnetic interactions and the corresponding antiferromagnetic-to-ferromagnetic phase transition via a strong magnetic field during the field cooling process.A non-monotonous structural transition of the MnO_(6) octahedral rotation can enlarge the strain gradient in PSMO film on a SrTiO_(3) *** work demonstrates the existence of the flexomagnetic effect in ultrathin manganite film,which should be applicable to other complex oxide systems.

关键词： Strain gradient Manganite film Octahedral rotation Flexomagnetic Magnetic interactions Phase transition

Surface effect induced phase transformation by Mn removal during annealing and its textures in cold-rolled high manganese transformation-induced plasticity steel

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2022年第3期29卷 494-502页

作者： Li-ying Liu ping yang Dan-dan Ma Xin-fu Gu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China

The surface effect induced transformation texture during vacuum annealing of cold-rolled high manganese transformation-induced plasticity(TRIP)steels was *** to Mn removal occurring at the surface layer,γ→δdiffusional phase transformation leads to the formation of hard pancake-shaped ferrite grains due to solution strengthening at the surface and the centre layer remains as austenite+martensite after *** the case of slow heating,{112}/{111}textures for the surface ferrite were strengthened with the increase in temperature and holding time,indicating an inheritance of rolling *** increasing the heating rate of annealing,the rotated cube texture was developed in surface *** kind of multiphase sandwich structure with hard ferrite surface layer and tough austenite dominant centre can increase tensile strength and should also improve deep drawing properties,therefore providing new possibility of controlling properties for the application of high manganese TRIP steel.

关键词： High manganese transformation-induced plasticity steel Surface effect Texture Microstructure Vacuum annealing

Orientation gradient on surface of non-oriented electrical steel annealed by γ → α transformation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2020年第1期27卷 88-95页

作者： Jin-hua Wang ping yang Wei-min Mao Feng-e Cui School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The microstructures and textures of the non-oriented electrical steel sheets under various annealing conditions were *** orientation gradient in the interior of grains appeared on the surface of steel sheets after α→γ→α transformation in various *** orientation gradient that appeared on the surface was inherited into the center of the steel sheet in H2 atmosphere,while that appeared only in the grains of the surface layer during γ→α transformation with N2 *** thin oxide scale was generated in various atmospheres containing traces of O2 and *** formation mechanism of orientation gradient is related to the thermal stress caused by the difference of thermal expansion coefficients between the oxide scale and the thin ferrite on the *** combined effect of phase transformation stress and thermal stress caused the plastic deformation of the thin ferrite grains on the surface in the initial stage of γ→α transformation,and then the orientations of the thin ferrite grains gradually rotated and caused the orientation gradient in the interior of grains.

关键词： Electrical steel Texture Phase transformation-Thermal stress Oxide scale

The Upper Bounds of Arbitrary Eigenvalues for Uniformly Elliptic Operators with Higher Orders

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2006年第4期22卷 589-598页

作者： Gao Jia Xiao-ping yang College of Science University of Shanghai for Science and Technology Shanghai 200093 China School of Science Nanjing University of Science and Technology Nanjing 210094 China

Let Ωbelong to R^m （m≥ 2） be a bounded domain with piecewise smooth and Lipschitz boundary δΩ Let t and r be two nonnegative integers with t ≥ r ＋ 1. In this paper, we consider the variable-coefficient eigenvalue problems with uniformly elliptic differential operators on the left-hand side and （-Δ）^T on the right-hand side. Some upper bounds of the arbitrary eigenvalue are obtained, and several known results are generalized.

关键词： Uniformly elliptic operator of any order eigeuvalue eigenfunction upper bound

Impact of water and sediment discharges on subaqueous delta evolution in yangtze Estuary from 1950 to 2010

在线全文

学校读者我要写书评

暂无评论

Water Science and Engineering 2014年第3期7卷 331-343页

作者： Yun-ping yang Yi-tian LI Yong-yang FAN Jun-hong ZHANG Key Laboratory of Engineering Sediment Tianjin Research Institute for Water Transport EngineeringMinistry of Transport State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University

In order to determine how the subaqueous delta evolution depends on the water and sediment processes in the yangtze Estuary, the amounts of water and sediment discharged into the estuary were studied. The results show that, during the period from 1950 to 2010, there was no significant change in the annual water discharge, and the multi-annual mean water discharge increased in dry seasons and decreased in flood seasons. However, the annual sediment discharge and the multi-annual mean sediment discharge in flood and dry seasons took on a decreasing trend, and the intra-annual distribution of water and sediment discharges tended to be uniform. The evolution process from deposition to erosion occurred at the -10 m and -20 m isobaths of the subaqueous delta. The enhanced annual water and sediment discharges had a silting-up effect on the delta, and the effect of sediment was greater than that of water. Based on data analysis, empirical curves were built to present the relationships between the water and sediment discharges over a year or in dry and flood seasons and the erosion/deposition rates in typical regions of the suhaqueous delta, whose evolution followed the pattern of silting in flood seasons and scouring in dry seasons. Notably, the Three Gorges Dam has changed the distribution processes of water and sediment discharges, and the dam＇s regulating and reserving functions can benefit the subaqueous delta deposition when the annual water and sediment discharges are not affected.

关键词： water discharge sediment discharge, seasonal change delta yangtze Estuary

Adaptive synchronization of a class of fractional-order complex-valued chaotic neural network with time-delay

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2021年第12期30卷 248-253页

作者： Mei Li Ruo-Xun Zhang Shi-ping yang College of Physics Hebei Normal UniversityShijiazhuang 050024China Department of Computer Science North China Electric Power UniversityBaoding 071003China College of Primary Education Xingtai UniversityXingtai 054001China

This paper is concerned with the adaptive synchronization of fractional-order complex-valued chaotic neural networks(FOCVCNNs)with *** chaotic behaviors of a class of fractional-order complex-valued neural network are ***,based on the complex-valued inequalities of fractional-order derivatives and the stability theory of fractional-order complex-valued systems,a new adaptive controller and new complex-valued update laws are proposed to construct a synchronization control model for fractional-order complex-valued chaotic neural ***,the numerical simulation results are presented to illustrate the effectiveness of the developed synchronization scheme.

关键词： adaptive synchronization fractional calculus complex-valued chaotic neural networks time-delay