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Trends in Extremes of Surface Humidity, Temperature, and Summertime Heat Stress in China

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Advances in Atmospheric Sciences 2001年第5期18卷 742-751页

作者： Julian x.l. wang and Dian J. Gaffen NOAA/ Air Resources laboratory, Silver Spring, MD, 20910, USA NOAA/ Air Resources laboratory Silver Spring USA

In the past half century, the mean summertime temperature in China has increased, with nights warm- ing more than days. Using surface station observations, we show that the frequency of extreme heat-stress events in China, caused by extremely hot and humid days as well as by heatwaves lasting for a few days, has increased over the period from 1951 to 1994 When humidity is high, hot weather can cause heat stress in humans. The increased heatrstress trend may pose a public health problem

关键词： Trend detection Climate change Public health

Experimental Studieson Gas－Particle Flows and Coal Combustion in New Generation Spouting－Cyclone Combustor

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Journal of Thermal Science 1996年第2期5卷 132-137页

作者： D.x. wang Z.H. Ma x.l. wang l.x. Zhou(Department of Engineering Mechanics,Tsinghua University, Beijing 100084, China) Department of Engineering Mechanics Tsinghua University Beijing China

Based on previous studies,an improved non-slagging spouting-cyclone combustor with two-stage combustion, organized in perpendicularly vortexing flows, is developed for clean coal combustion applied in small-size industrial furnaces and domestic furnaces. The isothermal model test and the combustion test give some encouraging results. In this studyt further improvement of the geometrical configuration was made, a visualizatiou method and a lDA system were used to study the gas-particle flow behavior,and the temperature and gas composition in combustion experiments were measured by using thermocouples and a COSA-6000-CD Portable Stack Analyzer. Stronger recirculation in the spouting zone and the strongly swirling effect in the cyclone zone were obtained in the improved combustor. The combustion temperature distribution is uniform. These results indicate that the improved geometrical configuration of the combustor is favorable to the stabilization of coal flame and the intensification of coal combustion, and it provides a basis for the practical application of this technique.

关键词： strongly swirling flows lDA measurement combustion

Neural Network Impedance Control for Robotic Deburring Process Honing

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Neural Network Impedance Control for Robotic Deburring Proce...

Controlled cationic ring-opening polymerization of l-lactide by organic ion pair: novel approach to isotactic-rich and crystalline polylactide

The 9th International Symposium on Advances in Abrasive Technology

作者： x.l. wang, Y. wang and Y.N. xue School of mechanical engineering, Shandong University, Jinan, 250061, China

The conventional constant controllers always result in an uneven chamfer for its characteristics in nature when the burrs vary highly in automated robotic deburring process. An adaptive impedance controller with a neural network compensator is proposed to deal with the burrs variations and achieve the desired chamfering contour. The controller is based on the impedance control, which is suitable for force tracking for its robustness towards disturbances and its reliability. A neural network compensator is integrated to modify the input command according to the contact force and reference position. The effectiveness of the proposed approach is shown by simulation experiments of the robotic deburring process and is compared with the conventional impedance control.

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Science China Chemistry 2025年第1期 394-402页

作者： Zhiqiang Ding Mingqian wang Zijing Zhou Bin wang Yuesheng li Tianjin Key laboratory of Composite & Functional Materials School of Materials Science and Engineering Tianjin University

living/controlled cationic ring-opening polymerization （ROP） of l-lactide is a promising approach to isotactic-rich and crystalline poly（l-lactide）.In contrast with the unsubstituted lactones,l-lA can not be polymerized by organic lewis acids or carbenium ions,and the state of the art in this field is the cationic ROP of l-lA catalyzed by Br?nsted acid/alcohol system via activated monomer ***,we reported the first example of controlled cationic ROP of l-lA by using Meerweintype ion pair[Me3O]+[B（C6F5）4]-as the catalyst.[Me3O]+[B（C6F5）4]-promoted rapid l-lA cationic polymerization in the absence of alcohol,producing isotactic-rich and crystalline PllA without transesterification and epimerization side *** activated chain end mechanism,involving twice SN2 substitution and configuration-inversion （S→R→S） with the assistance of released Me2O,was proposed and further verified by density functional theory and control *** work expands the catalytic toolbox of isotactic-rich and crystalline polylactide *** represents a unique example of cationic-controlled polymerization of l-lA catalyzed by an organic ion pair.

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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

Force and impulse multi-sensor based on flexible gate dielectric field effect transistor

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 214-220页

作者： Chao Tan Junling lü Chunchi Zhang Dong liang lei Yang Zegao wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other ***-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate ***,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of *** we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor *** systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 *** sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on ***,there was almost no performance loss for the device as left in the air for two months.

关键词： flexible gate dielectric transistor force sensor impulse sensor force sensor array

NUMERICAl SIMUlATION OF PARTIClE SEPARATION IN AN OIl-SAND SEPARATOR

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Journal of Hydrodynamics 2001年第1期13卷 81-85页

作者： Wei, x.l. Tian, W.D. wang, J.M. Sheng, H.Z. Inst. of Mechanics Chinese Acad. of Sci. Beijing 100080 China

The gathering systems of crude oil are greatly endangered by the fine sand and soil in oil. Up to now, how to separate sand from the viscid oil is still a technical problem for oil production at home or abroad. Recently, Institute of Mechanics in Chinese Academy of Sciences has developed a new type of oil-sand separator, which has been applied successfully in oil field in situ. In this paper, the numerical method of vortex-stream function is used to predict the liquid-solid separating course and the efficiency for this oil-sand separator. Results show that the viscosity and particle diameter have much influence on the particle motion. The calculating separating efficiency is compared with that of experiment and indicates that this method can be used to model the complex two-phase flow in the separator.

关键词： Computer simulation Crude petroleum Petroleum engineering Separators

CORROSION BEHAVIORS OF THE ExPOSED SIDE AND UNDERSIDE OF lOW AllOY WEATHERING STEEl IN QINGDAO AND WANNING FOR 18 MONTHS

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Acta Metallurgica Sinica(English letters) 2008年第6期21卷 425-436页

作者： S. T. wang S. W. Yang K. W. Gao x.l. He Department of Materials Physics and Chemistry University of Science and Technology Beijing Beijing 100083 China

For 18 months, a newly developed low alloy weathering steel has been exposed in two coastal sites （Qingdao in the north China, Wanning in the south China）. The different corrosion behaviors of the exposed side and the underside of the samples were characterized by x-ray diffraetion （xRD）, polarization curve, electrochemical impedance spectroscopy （EIS）, scanning electron microscopy （SEM）, and N2 adsorption approach. It was found that the samples exhibited higher corrosion rate in Wanning than that in Qingdao. The underside of the samples corrodes more seriously than the exposed side in Qingdao, whereas the result in Wanning is just the reverse. The protection performance of rust layers mainly depends on its compactness and the enrichment of Cu and Cr is a secondary causation. The different compactness of rust layers in the exposed side and the underside originates from different corrosion conditions of the two sides.

关键词： low alloy weathering steel Temperate marine environment Subtropical marine environment Exposed side Underside side

THEORETICAl STUDY OF GIANT MAGNETO-IMPEDANCE IN AMORPHOUS FIlMS WITH lONGITUDINAl MAGNETIC ANISOTROPY

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Acta Metallurgica Sinica(English letters) 2000年第4期13卷 995-1000页

作者： Yu, J.Q. Zhou, Y. Cai, B.C. Zhao, x.l. Shanghai Jiaotong Univ Shanghai China

Giant magneto-impedance (MI) effect in thin films with longitudinal magnetic anisotropy was studied theoretically. The effective permeability of films as a function of external magnetic field Ha, anisotropy field and other parameters of films was presented by landau-lifshitz-Gilbert theory. The theoretical results agree well with the experimental data, which shows a strong dependence of the impedance on the applied magnetic field.

关键词： Electric currents Magnetic anisotropy Magnetic fields Skin effect