检索结果-南通市图书馆

Research on Direct Yaw Moment Control Strategy of Distributed-Drive Electric Vehicle Based on Joint Observer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy Engineering 2021年第4期118卷 853-874页

作者： Quan Min Min Deng zichen Zheng Shu Wang Xianyong Gui Haichuan Zhang CCCC Second Highway Consultants Co. Ltd.Wuhan430056China School of Automobile Chang’an UniversityXi’an710064China Shaanxi Fast Auto Drive Group Co. Ltd.Xi’an710119China

Combined with the characteristics of the distributed-drive electric vehicle and direct yaw moment control,a double-layer structure direct yaw moment controller is *** upper additional yaw moment controller is constructed based on model predictive *** at minimizing the utilization rate of tire adhesion and constrained by the working characteristics of motor system and brake system,a quadratic programming active set was designed to optimize the distribution of additional yaw *** road surface adhesion coefficient has a great impact on the reliability of direct yaw moment control,for which joint observer of vehicle state parameters and road surface parameters is designed by using unscented Kalman filter algorithm,which correlates vehicle state observer and road surface parameter observer to form closed-loop feedback *** results show that compared to the“feedforward+feedback”control,the vehicle’s error of yaw rate and sideslip angle by the model predictive control is smaller,which can improve the vehicle stability *** addition,according to the results of the docking road simulation test,the joint observer of vehicle state and road surface parameters can improve the adaptability of the vehicle stability controller to the road conditions with variable adhesion coefficients.

关键词： Vehicle stability control distributed drive direct yaw moment control joint observer

Mg(NO_(3))_(2)·6H_(2O)-Assisted insitu-Fabrication of Tea Residual Biochar for Ultra-Fast and High Adsorption of Rhodamine B

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2024年第2期29卷 165-176页

作者： HU Dandan XUE Yangfan LIU Bo WU Yongjuan LI zichen School of Chemistry&Chemical Engineering Shaanxi Xueqian Normal UniversityXi'an 710100ShaanxiChina Safe College Xi􀆳an University of Science and TechnologyXi'an 710054ShaanxiChina

In this work,porous biochar(MN-TRB_(750))was fabricated via direct pyrolysis of tea residue(TR)and Mg(NO_(3))_(2)·6H_(2)O(MN).The as-synthesized MN-TRB_(750) reached a specific surface area of 839.54 m^(2)·g^(-1)and an average pore size of 3.75 nm with multi-level pore *** decreased TR's carbonization temperature and promoted the aromatics extent,pore structure for the frizzly flake-like *** B(RhB)was chosen as the adsorbate to explore the removal performance of organic dyes in this *** results indicated that the maximum adsorption capacity of RhB on MN-TRB_(750) at 20℃ is up to 809.0 mg·g^(-1)with isotherms fitted well to Freundlich and Dubinin-Radushkevic *** adsorption kinetics followed pseudo-second-order and Elovich models with an equilibrium adsorption capacity of 757.6 mg·g^(-1)as the initial concentration of RhB is 260 mg·L^(-1).High pore filling,hydrogen bond,π-πinteraction determined the adsorption of RhB onto MN-TRB850 through a multi-active center and exothermic chemical sorption process.

关键词： Mg(NO_(3))_(2)·6H_(2)O porous biochar mechanism rhodamine B adsorption

Theoretical and Applied Mechanics Letters

在线全文

学校读者我要写书评

暂无评论

Theoretical & Applied Mechanics Letters 2021年第2期11卷 63-69页

作者： Xuan Zhao Lin Du Xuhao Peng zichen Deng Weiwei Zhang College of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China National Key Laboratory Science and Technology on Aerodynamic Design and Research Northwestern Polytechnical UniversityXi’an 710072China School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710129China MIITKey Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi’an 710072China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710129China

The placement of pressure taps on the surface of the wind tunnel test model is an important means toobtain the surface pressure ***,limited by space location and experimental cost,it isdifficult to arrange enough pressure measuring taps on the surface of complex models to obtain completepressure distribution information,thus it is impossible to obtain accurate lift and moment characteristicsthrough *** paper proposes a refined reconstruction method of airfoil surface pressure basedon compressed sensing,which can reconstruct the pressure distribution with high precision with lesspressure measurement *** on typical airfoil subsonic flow around flow show that the accuracyof lift and moment after the pressure integration reconstructed by 4-8 measuring points can meet therequirements of the national military *** algorithm is robust to noise,and provides a new ideafor obtaining accurate force data from sparse surface pressure tests in engineering.

关键词： Pressure test Compressed sensing Proper orthogonal decomposition Pressure field reconstruction

Coupling effects of tungsten and molybdenum on microstructure and stress-rupture properties of a nickel-base cast superalloy

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2018年第1期28卷 45-53页

作者： Tongjin Zhou Wei Feng Huibin Zhao Yu Meng Huaxia Zhang Hongsheng Ding zichen Wang National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Beijing Institute of Aeronautical Materials

In order to comprehensively understand the forming mechanism of abnormal phases solidified in a nickel-base cast superalloy with additives of tungsten and molybdenum, the coupling effects of W and Mo on the microstructure and stress-rupture properties were investigated in this paper. The results indicated that the precipitation of primary α-（W, Mo） phase depended tremendously on the amount of W and Mo addition. When the total amount of W and Mo was greater than 5.79 at%, α-（W, Mo） phase became easily precipitated in the *** increasing of Mo/W ratio, the dendrite-like α-（W, Mo） phases were apt to convert into small bars or blockylike phases at the vicinities of γ′/γ eutectic. The morphological changes of α-（W, Mo） phase can be interpreted as the non-equilibrium solidification of W and Mo in the alloy. Since the large sized α-（W, Mo） phase has detrimental effects on stress-rupture properties in as-cast conditions, secondary cracks may mainly initiate at and then propagate along the interfaces of brittle phases and soft matrix. During exposing at 1100 ℃ for 1000 h, the α-（W, Mo） phases transformed gradually into bigger and harder M;C carbide, which results in decreasing of stress-rupture properties of the alloy. Finally, the alloy with an addition of 14W-1Mo（wt%） maintained the longest stress lives at high temperatures and therefore it revealed the best microstructure stability after 1100 ℃/1000 h thermal exposure.

关键词： Superalloy Tungsten and molybdenum Cast Microstructure Stress-rupture properties

Urchin-like Na-doped zinc oxide nanoneedles for low-concentration and exclusive VOC detections

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2024年第4期13卷 507-517页

作者： Yiwen Zhou Yifan Luo zichen Zheng Kewei Liu Xiaoxi He Kaidi Wu Marc Debliquy Chao Zhang College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China Material Science Department University of MonsMons 7000Belgium

In the early-stage diagnosis of lung cancer,the low-concentration(<5 ppm)volatile organic compounds(VOCs)are extensively identified to be the biomarkers for breath ***,the urchin-like sodium(Na)-doped zinc oxide(ZnO)nanoneedles were synthesized through a hydrothermal strategy with the addition of different contents of citric *** Na-doped ZnO gas sensor with a 3:1 molar ratio of Na^(+)and citric acid showed outstanding sensing properties with an optimal selectivity to various VOCs(formaldehyde(HCOH),isopropanol,acetone,and ammonia)based on working temperature ***,significantly enhanced sensitivity(21.3@5 ppm)compared with pristine ZnO(~7-fold),low limit of detection(LOD)(298 ppb),robust humidity resistance,and long-term stability of formaldehyde sensing performances were obtained,which can be attributed to the formation of a higher concentration of oxygen vacancies(20.98%)and the active electron ***,the improved sensing mechanism was demonstrated by the exquisite band structure and introduction of the additional acceptor level,which resulted in the narrowed bandgap of ZnO.

关键词： zinc oxide(ZnO) heterovalent ions doping citric acid gas sensor volatile organic compound(VOC)detection lungcancer

Pulse-burst laser-based 10kHz Thomson scattering measurements

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2019年第10期21卷 83-90页

作者： zichen HE Cary SMITH Zhili ZHANG Theodore M BIEWER Naibo JIANG Paul S HSU Sukesh ROY Mechanical Aerospace and Biomedical EngineeringUniversity of TennesseeKnoxville TN 37996 United States of America Fusion Energy Division Oak Ridge National LaboratoryOak Ridge TN 37931United States of America Spectral Energies LLC Dayton OH 45431United States of America

Thomson scattering (TS), as a popular and reliable diagnostic technique, has successfully measured electron temperatures and electron number densities of plasmas for many years. However, conventional TS techniques using Nd:YAG lasers operate only at tens of hertz. Here, we present the development of a high-repetition-rate TS instrument based on a high-speed, pulse-burst laser system to greatly increase the temporal resolution of measurements. Successful instrument prototype testing was carried out by collecting TS light from laboratory helium and argon plasmas at 10 kHz. Calibration of the instrument detection sensitivity using nitrogen/ oxygen rotational Raman scattering signal is also presented. Quantitative electron number densities and electron temperatures of the plasma were acquired at 10 kHz, for stable plasma discharges as, respectively,~0.9 eV and ~5.37×10^21 m^-3 for the argon plasma, and ~1 eV and ~6.5×10^21 m^-3 for the helium plasma.

关键词： Thomson scattering high-speed pulse-burst laser

Technical alternatives for coke oven gas utilization in China: A comparative analysis of environment-economic-strategic perspectives

在线全文

学校读者我要写书评

暂无评论

Environmental Science and Ecotechnology 2024年第5期21卷 168-177页

作者： zichen Di Feixia Lei Jiankai Jing Hao Peng Xi Lu Fangqin Cheng Institute of Resources and Environmental Engineering Shanxi UniversityTaiyuan030006PR China School of Environment State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing100084PR China Institute for Carbon Neutrality Tsinghua UniversityBeijing100084PR China

China is the largest coke producer and *** is a pressing need to address the high emissions of air pollutants and carbon dioxide associated with traditional coking *** the nation pursues a transition towards carbon neutrality,expanding supply chains for coking plants to produce hydrogen,methanol,and other green alternatives has garnered significant ***,the relative advantages of these strategies have remained *** this study,we integrate a life cycle assessmenteconomic analysis-scenario analysis model to evaluate various coke oven gas(COG)utilization routes(COGtM:COG-to-methanol,COGtLNG:COG-to-liquefied natural gas,COGtSA:COG-to-synthetic ammonia,and COGtH:COG-to-hydrogen).The results indicate that COGtSA emerges as the preferred option for balancing environmental and economic ***,COGtM demonstrates economic viability but is associated with higher environmental *** being recognized as a significant strategic direction under carbon neutrality initiatives,COGtH faces economic feasibility and risk resilience *** encounters both financial and environmental challenges,necessitating strategic development from an energy security *** projected coking capacity is anticipated to experience a slight increase in the mid-term yet a significant decline in the long term,influenced by steel production *** potential future markets,COGtM is estimated to potentially capture a maximum market share of 16e34%in the methanol ***,against the backdrop of continuously expanding potential demand for hydrogen,COGtH holds advantages as a transitional solution,but in the long run,it can only meet a small portion of the *** can meet 7e14%of market demand and emerges as the most viable pathway from the viewpoint of balancing environmental and economic aspects and covering future markets.

关键词： Coke oven gas Life cycle assessment Economic analysis Comprehensive benefits Transformation strategy

Pressureless two-step sintering of ultrafine-grained refractory metals:Tungsten-rhenium and molybdenum

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 Materials Science & Technology 2022年第31期126卷 203-214页

作者： Zhongyou Que zichen Wei Xingyu Li Lin Zhang Yanhao Dong Mingli Qin Junjun Yang Xuanhui Qu Ju Li Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

The challenge of sintering ultrafine-grained refractory metals and alloys to full density is hereby addressed by pressureless two-step sintering in tungsten-rhenium alloy and pure molybdenum. Using properly processed nano powders(~50 nm average particle size), we are able to sinter W-10Re alloy to 98.4% density below 1200 ℃ while maintaining a fine grain size of 260 nm, and sinter molybdenum to 98.3% density below 1120 ℃ while maintaining a fine grain size of 290 nm. Compared to normal sintering,two-step sintering offers record-fine grain sizes and better microstructural uniformity, which translates to better mechanical properties with higher hardness(6.3 GPa for tungsten-rhenium and 4.0 GPa for molybdenum, both being the highest in all pressurelessly sintered samples of the respective material system)and larger Weibull modulus. Together with our previous demonstration in tungsten, we believe that twostep sintering is a general effective method to produce high-quality fine-grained refractory metals and alloys, and the lessons learned here are transferable to other materials for powder metallurgy.

关键词： Powder metallurgy Refractory metals Porosity Two-step sintering Grain growth

Hyperbranched magnetic polymer:highly efficient removal of Cr(Ⅵ)and application in electroplating wastewater

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2023年第10期17卷 1568-1580页

作者： Nan Sun Qing Wu Lifang Jin zichen Zhu Jianhui Sun Shuying Dong Haijiao Xie Chunyan Zhang Yanrui Cui Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control Ministry of Educationand Henan Key Laboratory for Environmental Pollution ControlSchool of EnvironmentHenan Normal UniversityXinxiang 453007China

By using a two-step hydrothermal method and trithiocyanuric acid(TTCA),2,4,6-trihydrazino-1,3,5-triazine(THT),and Fe_(3)O_(4)as raw materials,a spherical magnetic adsorbent polymer(TTCA/THT@Fe_(3)O_(4))was synthesized to achieve the efficient removal of Cr(VI)from *** optimal adsorption conditions,the maximum adsorption capacity of TTCA/THT@Fe_(3)O_(4)for Cr(VI)can reach 1340 mg∙g‒***,the removal efficiency can approach 98.9%,even at the lower concentration of 20 mg∙L^(‒1)Cr(VI).For actual wastewater containing Cr(VI),the Cr(VI)concentration was reduced from 25.8 to 0.4 mg∙L^(‒1),a remarkable 20%lower than the current industry discharge standard value.A mechanism for the high adsorption performance of Cr(VI)on TTCA/THT@Fe_(3)O_(4)was investigated using Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,and density functional *** can be plausibly attributed to the formation of Cr/N and Cr/S coordination ***,surface electrostatic adsorption,reduction effects,and the spherical polymer structure increase the contact area with Cr(VI),maximizing *** synergistic effect of adsorption and reduction enhances the adsorption performance of TTCA/THT@Fe_(3)O_(4)for Cr(VI)and total chromium in *** resultant polymer has a simple preparation process,excellent adsorption performance,easy magnetic separation,and promising application for actual wastewater.

关键词： magnetic polymer chromium removal hydrogen bonding recyclability actual wastewater