检索结果-南通市图书馆

INFLUENCINg FACTORS FOR OBTAININg ULTRAFINE AUSTENITE gRAINS WITH INITIAL MICROSTRUCTURE OF WARM-ROLLEd FERRITE/PEARLITE

在线全文

学校读者我要写书评

暂无评论

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

EFFECT OF COPPER ON THE HOT PLASTICITY OF 304HC STAINLESS STEEL

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2005年第5期18卷 674-678页

作者： g.Z. Cui H.S. di g.d. wang X. H. Liu State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

The plasticity map of 304HC stainless steel was determined by using tensile and compressive test. The effect of Cu on the hot plasticity of 304HC stainless steel was analyzed. The microstructure, inclusion and fracture surface were studied by using the method of optical microscopy, SEM, EdS and EPMA. The results showed that Cu has effect on the hot plasticity and the hot plasticity of 304HC stainless steel decrease with the increase of Cu content. The deformation temperature also has much effect on the hot plasticity, the suitable deformation temperature are 1100-1200℃. The reason is that the brittle compounds were precipitated from austenite during cooling. These brittle compounds are Cu2S, Cu2O and PbCI etc.

关键词： 304HC stainless steel hot plasticity brittle compounds precipitation,impurity crack microstructure

NUMERICAL SIMULATION OF MOLTEN POOL ANd CONTROL STRATEgY OF KISS POINT IN A TWIN-ROLL STRIP CASTINg PROCESS

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 459-468页

作者： g.M. Cao C.g. Li Z. Y. Liu d. Wu g.d. wang X.H. Liu State Key Laboratory of Rolling ＆ Automation Northeastern University Shenyang 110004 China

Coupled turbulent flow, temperature fields of the twin-roll casting strip process were simulated by three-dimensional finite element method. Based on the heat balance calculation and using inverse methods between the simulations and real experiments, the relational models among casting speed, location, and coefficient of heat transfer between molten metal and rolls in different regions are given. In the simulation, the calculated surface temperatures are in good agreement with the measured values. An on-line model of kiss point is derived by simulations and the geometry of molten pool, corresponding control strategy is also proposed.

关键词： Twin-roll strip casting Coupled temperature and flow field Numerical simulation Kiss point Control strategy

SIMULATION OF THE TWIN ROLL STAINLESS STRIP CASTINg PROCESS

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2001年第3期14卷 199-204页

作者： Y.C. Miao, X.M. Zhang, g.d. wang, H.S. di and X.H. Liu (State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110004, China) State Key Laboratory of Rolling and Automation Northeastern University

The position of the solidification completed temperature of twin roll stainless strip casting process is very important to the quality of the casting strip. In order to control this position, the solidification completed temperature should be known at first. The present paper first simulated dendritic microsegregation under conditions of twin roll stainless strip casting, and got the relationship between the temperature and the solid fraction of the mush zone. The temperatures such as ZdT (equal to the solidification completed temperature) and LIT (liquid impenetrable temperature), et al., also can be found from this relationship. Then by using the turbulent model, the flow and thermal fields of the pool of the twin roll stainless strip casting and the speed and temperature fields of different casting speeds were given and also explained. The simulation results are coincident with the experimental results. Combined with the results of these simulations, the appropriated casting speed was found.

关键词： Computer simulation Continuous casting Segregation (metallography) Stainless steel Turbulence

A Study of Transformation from deformed Austenite to Ferrite in Low Carbon Steels by Cellular Automaton

在线全文

学校读者我要写书评

暂无评论

A Study of Transformation from Deformed Austenite to Ferrite...

Wafer-Scale Vertical 1d gaN Nanorods/2d MoS₂/PEdOT:PSS for Piezophototronic Effect-Enhanced Self-Powered Flexible Photodetectors

第二届先进钢铁结构材料国际会议

作者： L. Zhang C.B. Zhang L. X. du X.H. Liu g.d. wang The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110006 China The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110006 China College of Science Northeastern University Shenyang 110006 China The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110006 China The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110006 China The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110006 China

＜正＞A cellular automaton simulation is used to study the role of nucleation at austenite grain boundaries in the transformation from deformed austenite to ferrite for low carbon steels at large cooling rates. The simulation results show that the ferrite grain size of low-carbon steels can be refined in the case of deformed austenite at the large cooling rates. The apparent increase in the number of ferrite nuclei can only take place in a large undercooling temperature. However, the effect on this transformation is quite limited through increasing the nucleation number at austenite grain boundaries in the case of deformed austenite compared with that in the case of undeformed austenite. In such cases, cooling conditions play a main role in determining the resultant ferrite grain size.

关键词： Phase Transformation Alloy Computer Simulation Cellular Automaton

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

NANO-MICRO LETTERS 2025年第1期17卷 1-15页

作者： Tang, Xin Jiang, Hongsheng Lin, Zhengliang wang, Xuan wang, Wenliang Li, guoqiang South China Univ Technol State Key Lab Luminescent Mat & Devices Guangzhou 510640 Peoples R China South China Univ Technol Sch Mat Sci & Engn Dept Elect Mat Guangzhou 510640 Peoples R China

Vertical 1d gaN nanorod arrays/2d MoS2/PEdOT:PSS heterostructures in wafer scale have been fabricated for flexible photodetection ***-powered flexible photodetector at compressive strain reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W-1 and response times of 40/45 mu s, which are superior to the state-of-the-art flexible *** work not only provides a valuable strategy for the design and construction of tunable van der Waals heterostructures, but also opens a new opportunity for flexible sensors. van der Waals (vdW) heterostructures constructed by low-dimensional (0d, 1d, and 2d) materials are emerging as one of the most appealing systems in next-generation flexible photodetection. Currently, hand-stacked vdW-type photodetectors are not compatible with large-area-array fabrication and show unimpressive performance in self-powered mode. Herein, vertical 1d gaN nanorods arrays (NRAs)/2d MoS2/PEdOT:PSS in wafer scale have been proposed for self-powered flexible photodetectors arrays firstly. The as-integrated device without external bias under weak UV illumination exhibits a competitive responsivity of 1.47 A W-1 and a high detectivity of 1.2 x 1011 Jones, as well as a fast response speed of 54/71 mu s, thanks to the strong light absorption of gaN NRAs and the efficient photogenerated carrier separation in type-II heterojunction. Notably, the strain-tunable photodetection performances of device have been demonstrated. Impressively, the device at - 0.78% strain and zero bias reveals a significantly enhanced photoresponse with a responsivity of 2.47 A W-1, a detectivity of 2.6 x 1011 Jones, and response times of 40/45 mu s, which are superior to the state-of-the-art self-powered flexible photodetectors. This work presents a valuable avenue to prepare tunable vdWs heterostructures for self-powered flexible photodetection, which performs well in flexible sensors.

关键词： Vertical nanorod arrays van der Waals heterostructure Piezophototronic effect Self-powered photodetection Flexible sensors

Cortico-striatal gamma oscillations are modulated by dopamine d3 receptors in dyskinetic rats

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第4期20卷 1164-1177页

作者： Pengfei wang Yuewei Bi Min Li Jiazhi Chen Zhuyong wang Huantao Wen Ming Zhou Minjie Luo wangming Zhang Neurosurgery Center Department of Pediatric NeurosurgeryGuangdong Provincial Key Laboratory on Brain Function Repair and RegenerationZhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

Long-term levodopa administration can lead to the development of levodopa-induced *** oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced ***,studies have reported increased oscillation power in cases of levodopa-induced ***,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced ***,the role of the dopamine d3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is *** found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s ***,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma *** of Pd128907(a selective dopamine d3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum ***,administration of Pg01037(a selective dopamine d3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum *** findings suggest that the dopamine d3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia.

关键词： aperiodic components dopamine d3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials neuromodulation Parkinson’s disease primary motor cortex

Velocity profiles and energy fluctuations in simple shear granular flows

在线全文

学校读者我要写书评

暂无评论

Particuology 2016年第4期14卷 80-87页

作者： Chuanqi Liu Qicheng Sun gordon g.d. Zhou State Key Laboratory for Hydroscience and Engineering Tsinghua University Beijing 100084 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China

Rheology analysis of granular flows is important for predicting geophysical hazards and designing industrial processes. Using a discrete element method, we simulate simple shear flows in 3d under a constant confining pressure of 10 kPa. The inertial number proposed by the gdR Midi group in France is adopted to distinguish rheology regimes, Both translational and angular velocity profiles are investigated, and both fluid-like and solid-like behavior modes are observed in the flows. The maximum angular velocity occurs near the localized deformation area. We also investigate the energy characteristics of the flows and find that at very small shearing speed, the mean kinetic energy density ek is close to zero, while the mean elastic energy density ec is much greater. At large shearing speed, ek increases. The fluctuating parts of the two types of energy increase with increasing shear speed. Thus, the mean energy density ratio ek/ec can be used in addition to the inertial number to distinguish flow regimes. These results provide insights from energetics into the rheological properties of granular flows.

关键词： dense granular flows Simple shear Energy fluctuations

EXPERIMENTAL STUdY ON BEd RESISTANCE CHARACTERISTICS OF NONUNIFORM SEdIMENT

维普期刊数据库评论

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 Hydrodynamics 2000年第4期12卷 66-74页

作者： Zhou, g.d. Liu, Q.Y. wang, g.X. Hui, Y.J. Pang, d.M. Tsinghua Univ. Beijing 100084 China

Under natural circumstances, the bed of fluvial river is composed of nonuniform sediment, and its nonuniform property influences very much the bed resistance and flow characteristics. By using a one-dimensional laser velocimeter, flume experiments are carried out to analyze the resistance characteristics of open channel flow with the bed sediment composed of different representative particles and having.d.fferent nonuniform properties. By means of separating factors, the factors affecting the bed resistance, including particle diameter, nonuniform property and flow conditions, are studied. A great number of laboratory test results and field data from other investigators have been analyzed.

关键词： Sediments