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Intelligent Control of Cabin Environment Using Computational Fluid Dynamics for Intelligent Manufacturing

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Fluid Dynamics & Materials Processing 2022年第3期18卷 563-576页

作者： Xi Wang Guangping Zeng School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China

An efficient and versatile intelligent algorithm is developed for the control of the cabin environment of wind power generators.The method can be used to monitor and solve wind power generation problems at the same time.It also provides several advantages with respect to other traditional methods which imply significant workload and maintenance personnel.The functional requirements of the intelligent control system are analyzed,and a control algorithm for the stepping motor is selected and evaluated.Through the comparative analysis of the active power and internal temperature curve for three kinds of output power of the prototype,it is proved that the environmental intelligent control system greatly improves the operation efficiency,solves typical problems in the ventilator room environment,and provides a solid theoretical basis for further research in this field.

关键词： Wind turbine cabin environment control system computational fluid dynamics

Catalytic diastereoselective construction of multiple contiguous quaternary carbon stereocenters via [2+2] cycloaddition and mechanistic insight

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Chinese Chemical Letters 2023年第3期34卷 288-292页

作者： Xi Wang Fujie Liu Tao Xu Molecular Synthesis Center&Key Laboratory of Marine Drugs Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

Multiple contiguous quaternary carbon stereocenters(CQS) are highly challenging, yet important structural motifs in organic synthesis. Here, we describe a visible light induced catalytic [2 + 2] cycloaddition approach that constructed up to four CQS in a pentacyclic fused ring system diastereoselectively, from the readily accessible dienamides with pendent heteroaryls. Variously substituted dienamides have been cyclized with heteroaryls to provide a range of novel CQS-containing scaffolds(26 examples, up to 96%yield and >20:1 dr ratio). Mechanistic studies revealed that it may proceed through an uncommon β-C radical initiated 7-endo cyclization from the biradical intermediate.

关键词： Contiguous quaternary carbon stereocenters [2+2]Cycloaddition Fused ring system

Engineering Spin States of Isolated Copper Species in a Metal-Organic Framework Improves Urea Electrosynthesis

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Nano-Micro Letters 2023年第9期15卷 536-549页

作者： Yuhang Gao Jingnan wang Yijun Yang Jian wang Chuang Zhang Xi Wang Jiannian Yao Key Laboratory of Photochemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Molecular Plus and Collaborative Innovation Center of Chemical Science and Engineering Tianjin UniversityTianjin 300072People’s Republic of China Department of Physics School of Physical Science and EngineeringBeijing Jiaotong UniversityBeijing 100044People’s Republic of China Research Center for Magnetic and Spintronic Materials National Institute for Materials Science Tsukuba 305-0047Japan

The catalytic activities are generally believed to be relevant to the electronic states of their active center, but understanding this relationship is usually difficult. Here, we design two types of catalysts for electrocatalytic urea via a coordination strategy in a metal–organic frameworks: Cu^(Ⅲ)-HHTP and Cu^(Ⅱ)-HHTP. Cu^(Ⅲ)-HHTP exhibits an improved urea production rate of 7.78 mmol h^(−1)g^(−1) and an enhanced Faradaic efficiency of 23.09% at-0.6 V vs. reversible hydrogen electrode, in sharp contrast to Cu^(Ⅱ)-HHTP.Isolated CuⅢspecies with S = 0 spin ground state are demonstrated as the active center in Cu^(Ⅲ)-HHTP, different from Cu^(Ⅱ) with S = 1/2 in Cu^(Ⅱ)-HHTP. We further demonstrate that isolated Cu^(Ⅲ)with an empty dx2-y20orbital in Cu^(Ⅲ)-HHTP experiences a single-electron migration path with a lower energy barrier in the C–N coupling process, while Cu^(Ⅱ)with a single-spin state( d_(x2-y2)^(1)) in Cu^(Ⅱ)-HHTP undergoes a two-electron migration pathway.

关键词： Electrocatalysis Urea synthesis Metal-organic framework Spin catalysis C-N coupling

Dual-interlayers constructed by Ti_(3)C_(2)T_(x)/ionic-liquid for enhanced performance of solid garnet batteries

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Journal of Energy Chemistry 2023年第3期78卷 47-55,I0002页

作者： Xi Wang Yong wang Yiyu Wu Yunmiao Fan Yang Tian Department of Chemistry Analytical Instrumentation CenterCapital Normal UniversityBeijing 100048China

Li(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO) solid garnet-type electrolyte has been widely reported due to its outstanding safety and electrochemical stability.However,the inherent rigidity and brittleness of LLZTO lead to poor contact with anode/cathode and the operation failure of full cells.Herein,the dual-interlayers are constructed as the fast interfacial ion-migration channel by using Ti_(3)C_(2)T_(x)(MXene,Txis-O,-OH,-F) with trace ionic liquid(IL),which promote the intimate contact between LLZTO and anode/cathode and suppress Li-dendrites growth.Notably,IL can wet the cathode to promote intimate interface contact and be decomposed into some inorganic compounds(such as Li3N,LiF,and Li2Sx),resulting in reduced interfacial resistance and fast Li-ion transportation.Consequently,in the prepared Li-symmetric cell,the interfacial resistance on the anode side plunges to 33.1 Ω cm^(-2),and stably maintains over 1000 h without short circuit at 0.05 mA cm^(-2).The full cell of Li|LiFePO4delivers a high initial capacity of 158.52 mA h g^(-1)and outstanding retention of 90.18% after 100 cycles at 60℃ and 0.2 C.Our work provides an efficient strategy to design dual-interlayers between LLZTO and anode/cathode for the interfacial modification to enhance the performance of solid garnet batteries.

关键词： MXene composite Interfacial modiﬁcation Garnet electrolyte Solid battery Ion-transportation

Vascular protection by high-density lipoprotein-associated sphingosine-1- phosphate

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Journal of Geriatric Cardiology 2017年第11期14卷 696-702页

作者： Xi Wang Fan wang Department of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China

流行病学的研究和动物实验一致地由高密度的脂蛋白(HDL ) 表明了心血管的保护。从越来越多的研究的调查结果进一步显示 sphingosine-1-phosphate (S1P ) 调停许多心血管的系统上的 HDL 的有益的效果包括 vasodilatation， angiogenesis... 详细信息

流行病学的研究和动物实验一致地由高密度的脂蛋白(HDL ) 表明了心血管的保护。从越来越多的研究的调查结果进一步显示 sphingosine-1-phosphate (S1P ) 调停许多心血管的系统上的 HDL 的有益的效果包括 vasodilatation， angiogenesis， endothelial 障碍功能的维护，和对动脉粥样硬化和 ischemia/reperfusion 损害的保护。在这评论，我们总结为这些调查结果的临床的翻译在心血管的健康和热点潜力机会上调查 HDL-S1P 的效果的最近的文学。

关键词：脂蛋白高密度保护磷酸盐脉管动脉粥样硬化调查结果心血管

A combined experimental and analytical method to determine the EHL friction force distribution between rollers and outer raceway in a cylindrical roller bearing

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Friction 2023年第8期11卷 1455-1469页

作者： Yu HOU Xi Wang Di YANG Zeliang xiAO School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Hunan Provincial Key Laboratory of Intelligent Manufacturing Technology for High-performance Mechanical Equipment Changsha University of Science and TechnologyChangsha 410114China

Friction force is a crucial factor causing power loss and fatigue spalling of rolling element bearings.A combined experimental and analytical method is proposed to quantitatively determine the elastohydrodynamic lubrication(EHL)friction force distribution between rollers and outer raceway in a cylindrical roller bearing(CRB).An experimental system with the instrumented bearing and housing was developed for measuring radial load distribution and friction torque of bearings.A simplified model of friction force expressed by dimensionless speed,load,and material parameters was given.An inequality constrained optimization problem was established and solved by using an experimental data-driven learning algorithm for determining the uncertain parameters in the model.The effect of speed,load,and lubricant property on friction force and friction coefficient was discussed.

关键词： cylindrical roller bearing(CRB) elastohydrodynamic lubrication(EHL) friction force distribution friction torque combined method

Bracelet salt glands of the recretohalophyte Limonium bicolor:Distribution,morphology,and induction

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Journal of Integrative Plant Biology 2023年第4期65卷 950-966页

作者： Boqing Zhao Yingli Zhou xiangmei Jiao Xi Wang Baoshan wang Fang Yuan Shandong Provincial Key Laboratory of Plant Stress College of Life SciencesShandong Normal UniversityJi'nan 250014China

Halophytes complete their life cycles in saline environments.The recretohalophyte Limonium bicolor has evolved a specialized salt secretory structure,the salt gland,which excretes Na+to avoid salt damage.Typical L.bicolor salt glands consist of 16 cells with four fluorescent foci and four secretory pores.Here,we describe a special type of salt gland at the base of the L.bicolor leaf petiole named bracelet salt glands due to their beaded-bracelet-like shape of blue auto-fluorescence.Bracelet salt glands contain more than 16 cells and more than four secretory pores.Leaf disc secretion measurements and non-invasive micro-test techniques indicated that bracelet salt glands secrete more salt than normal salt glands,which helps maintain low Na+levels at the leaf blade to protect the leaf.Cytokinin treatment induced bracelet salt gland differentiation,and the developed ones showed no further differentiation when traced with a living fluorescence microscopy imager,even though new salt gland development and leaf expansion were observed.Transcriptome revealed a NAC transcription factor gene that participates in bracelet salt gland development,as confirmed by its genome editing and overexpression in L.bicolor.These findings shed light on bracelet salt gland development and may facilitate the engineering of salt-tolerant crops.

关键词： bracelet salt gland 6‐BA differentiation NAC transformation

Protective efficacy of a universal influenza mRNA vaccine against the challenge of H1 and H5 influenza A viruses in mice

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mLife 2023年第3期2卷 308-316页

作者： Yulei Li Xi Wang xi Zeng Wenbo Ren Pu Liao Baoli Zhu Savaid Medical School University of Chinese Academy of SciencesBeijingChina The Key Laboratory of Molecular Pathology(Hepatobiliary Diseases)of Guangxi Department of PathologyThe Affiliated Hospital of Youjiang Medical University for NationalitiesBaiseChina CAS Key Laboratory of Pathogenic Microbiology and Immunology Chinese Academy of SciencesBeijingChina Beijing Children's Hospital Capital Medical UniversityBeijingChina College of Life Sciences Jiangxi Science and Technology Normal UniversityNanchangChina Department of Clinical Laboratory Chongqing General HospitalChongqingChina University of Chinese Academy of Sciences BeijingChina Department of Pathogenic Biology School of Basic Medical SciencesSouthwest Medical UniversityLuzhouChina

Current influenza vaccines need to be updated annually owing to constant antigenic drift in the globular head of the viral surface hemagglutinin(HA)glycoprotein.The immunogenic subdominant stem domain of HA is highly conserved and can be recognized by antibodies capable of binding multiple HA subtypes.Therefore,the HA stem antigen is a promising target for the design of universal influenza vaccines.On the basis of an established lipid nanoparticle-encapsulated mRNA vaccine platform,we designed and developed a novel universal influenza mRNA vaccine(mHAs)encoding the HA stem antigen of the influenza A(H1N1)virus.We tested the efficacy of the mHAs vaccine using a mouse model.The vaccine induced robust humoral and specific cellular immune responses against the stem region of HA.Importantly,two doses of the mHAs vaccine fully protected mice from lethal challenges of the heterologous H1N1 and heterosubtypic H5N8 influenza viruses.Vacci-nated mice had less pathological lung damage and lower viral titers than control mice.These results suggest that an mRNA vaccine using the conserved stem region of HA may provide effective protection against seasonal and other possible influenza variants.

关键词： immunogenicity influenza virus mRNA vaccine universal vaccine

Design,Hydrodynamic Analysis,and Testing of a Bio-inspired Movable Bow Mechanism for the Hybrid-driven Underwater Glider

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Journal of Bionic Engineering 2023年第4期20卷 1493-1513页

作者： Yanhui wang Yudong Guo Shaoqiong Yang Tongshuai Sun Xi Wang Huihui Zhou Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin300072China The Joint Laboratory of Ocean Observing and Detection Laoshan LaboratoryQingdao266237China

Hybrid-driven Underwater Glider(HUG)is a new type of underwater vehicle which integrates the functions of an Autonomous Underwater Glider(AUG)and an Autonomous Unmanned Vehicle(AUV).Although HUG has the characteristics of long endurance distance,its maneuverability still has room to be improved.This work introduces a new movement form of the neck of the underwater creature into HUG and proposes a parallel mechanism to adjust the attitude angle and displacement of the HUG’s bow,which can improve the steering maneuverability.Firstly,the influence of bow movement and rotation on the hydrodynamic force and flow field of the whole machine is analyzed by using the Computational Fluid Dynamics(CFD)method.The degree of freedom,attitude control range and movement amount of the Movable Bow Mechanism(MBM)are obtained,and then the design of MBM is completed based on these constraints.Secondly,the kinematic and dynamic models of MBM are established based on the closed vector method and the Lagrange equation,respectively,which are fully verified by comparing the results of simulation in Matlab and Adams software,then a Radial Basis Function(RBF)neural network adaptive sliding mode controller is designed to improve the dynamic response effect of the output parameters of MBM.Finally,a prototype of MBM is manufactured and assembled.The kinematic,dynamics model and controller are verified by experiments,which provides a basis for applying MBM in HUGs.

关键词： Underwater glider Movable bow mechanism Hydrodynamic simulation Steering maneuverability