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Biomimetic 3D printing of composite structures with decreased cracking

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Nanotechnology and Precision engineering 2024年第3期7卷 24-34页

作者： Fan Du Kai li Mingzhen li Junyang Fang Long Sun Chao Wang Yexin Wang Maiqi liu Jinbang li Xiaoying Wang School of mechanical engineering and Mechanics Ningbo UniversityNingbo 315211China School of mechanical and Electrical engineering China University of Mining and TechnologyXuzhou 221116China Institute of Advanced energy Storage Technology and Equipment Ningbo UniversityNingbo 315211China School of Civil and Environmental engineering and Geography Science Ningbo UniversityNingbo 315211China

The development of tissue engineering and regeneration research has created new platforms for bone ***,the preparation of scaffolds with good fiber integrity is challenging,because scaffolds prepared by traditional printing methods are prone to fiber cracking during solvent *** skin has an excellent natural heat-management system,which helps to maintain a constant body temperature through perspiration or blood-vessel *** this work,an electrohydrodynamic-jet 3D-printing method inspired by the thermal-management system of skin was *** this system,the evaporation of solvent in the printed fibers can be adjusted using the temperature-change rate of the substrate to prepare 3D structures with good structural *** investigate the solvent evaporation and the interlayer bonding of the fibers,finite-element analysis simulations of a three-layer microscale structure were carried *** results show that the solvent-evaporation path is from bottom to top,and the strain in the printed structure becomes smaller with a smaller temperaturechange *** results verified the accuracy of these simulation results,and a variety of complex 3D structures with high aspect ratios were *** cracks were reduced to the nanoscale by adjusting the temperature-change rate from 2.5 to 0.5℃*** process parameters were selected to prepare a tissue engineering scaffold with high *** was confirmed that this printed scaffold had good biocompatibility and could be used for bone-tissue *** simple and flexible 3D-printing method can also help with the preparation of a wide range of micro-and nanostructured sensors and actuators.

关键词： 3D printing Electrohydrodynamic jet Biomimetic Structural integrity Composite scaffold

Research on Chemical mechanical Planarization for Functional Ceramics

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厦门大学学报（自然科学版） 2002年第S1期41卷 52-53页

作者： YUAN Ju-long, liN Xu, Lü Bing-hai, JI Shi-ming, ZHANG li-bin (mechanical and Electronic engineering college, zhejiang university of Technology, hangzhou 310014, china)

Presently, the products of functional ceramic are widely applied in the light & mechatronics fields such as communication, aeronautic and astronautic engineering, military affairs and home-use electrical appliance etc. It’s performance of working is mainly determined by the physical performance of the surface. And therefore the roughness and the affected layer’s depth of the final processing surface have a direct influence to the performance of the device. It is obvious that how to guarantee the processing quality of functional ceramic is a kernel problem whether it can achieve the purpose of application or not. Ultra-precision planarization is usually as the final processing method of functional ceramic substrates, and the mirror surface of Ra 0.01～0.002 μm can be obtained by ultra-precision polishing. For the ultra-precision planarization processing of functional ceramic material, simplex chemical or mechanical polishing method is very difficult to achieve the technic demands, and furthermore various defects of processing exist in the surface of crystal after planarization. However, chemical mechanical planarization (CMP) which has emerged recently as a new indispensable processing technique for higher degree planarization of functional ceramic is be able to satisfy the processing requests from the aspects of processing performance and rate. The current paper systematically introduces the processing course of functional ceramic by using chemical mechanical planarization. In addition, material removal mechanism is analyzed, and the choosing of processing conditions and components and effect of polishing slurry are discussed. Then the present research status and development trend of CMP technology for functional ceramic are discussed. Finally the current existing main questions and their solutions are presented.

关键词： functional ceramic CMP no damage layer

Research on Abrasives in the Chemical mechanical Polishing Process for Silicon Nitride Balls

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厦门大学学报（自然科学版） 2002年第S1期41卷 63-64页

作者： YUAN Ju-long, Lü Bing-hai, liN Xü, JI Shi-ming, ZHANG li-bin (mechanical and Electronic engineering college, zhejiang university of Technology, hangzhou 310014, china)

Silicon nitride (Si 3N 4) has been the main material for balls in ceramic ball bearings, for its lower density, high strength, high hardness, fine thermal stability and anticorrosive, and is widely used in various fields, such as high speed and high temperature areojet engines, precision machine tools and chemical engineer machines. Silicon nitride ceramics is a kind of brittle and hard material that is difficult to machining. In the traditional finishing process of silicon nitride balls, balls are lapped by expensive diamond abrasive. The machining is inefficiency and the cost is high, but also lots of pits, scratch subsurface micro crazes and dislocations will be caused on the surface of the balls, the performance of the ball bearings would be declined seriously. In these year, a kind of new technology known as chemical mechanical polishing is introduced in the ultraprecision machining process of ceramic balls. In this technology, abrasives such as ZrO 2, CeO 2 whose hardness is close to or lower than the work material (Si 3N 4) are used to polishing the balls. In special slurry, these abrasives can chemo-mechanically react with the work material and environment (air or water) to generate softer material (SiO 2). And the resultants will be removed easily at 0.1 nm level. So the surface defects can be minimized, very smooth surface (Ra=4 nm) and fine sphericity (0.15～0.25 μm ) can be obtained, and the machining efficiency is also improved. The action mechanism of the abrasives in the chemical mechanical polishing process in finishing of silicon nitride ball will be introduced in this paper.

关键词： silicon nitride ball chemical mechanical polishing abrasives

A high li-ion diffusion kinetics in multidimensional and compact-structured electrodes via vacuum filtration casting

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Journal of energy Chemistry 2024年第6期93卷 368-376,I0010页

作者： Jieqiong li Ting Ouyang Lu liu Shu Jiang Yongchao Huang M.-Sadeeq Balogun college of Materials Science and engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082HunanChina Institute of Environmental Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006GuangdongChina

Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(liBs).However,simultaneously regulating these criteria for liBs is desirable but remains a significant *** this work,niobium pentoxide(Nb_(2)O_(5))anode and lithium iron phosphate(liFePO_(4))cathode materials were chosen as the model materials and demonstrate that these three parameters can be simultaneously modulated by incorporation of micro-carbon fibers(MCF)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum filtration *** as-prepared MNC-20 anode and MLC-20 cathode achieves high reversible areal capacity of≈5.4 m A h cm^(-2)@0.1 C and outstanding li-ion diffusion coefficients of≈10~(-8)cm~2 s~(-1)in the half-cell *** assembled MNC-20‖MLC-20 full cell liB delivers maximum energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),*** excellent electrochemical properties of the asprepared thick electrodes can be attributed to the highly conductive,mechanical compactness and multidimensional mutual effects of the MCF,CNT and active materials that facilitates rapid li-ion diffusion ***,electrochemical impedance spectroscopy(EIS),symmetric cells analysis,and insitu Raman techniques clearly validates the enhanced li-ion diffusion kinetics in the present architecture.

关键词： Thick electrodes Carbon nanotubes li-ion diffusion co-efficient Vacuum filtration technique High areal capacity lithium-ion batteries

Reinforcement Learning-Based energy Management for Hybrid Power Systems:State-of-the-Art Survey,Review,and Perspectives

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Chinese Journal of mechanical engineering 2024年第3期37卷 1-25页

作者： Xiaolin tang Jiaxin Chen Yechen Qin Teng liu Kai Yang Amir Khajepour Shen li college of mechanical and Vehicle engineering Chongqing UniversityChongqing 400044China School of mechanical engineering Beijing Institute of TechnologyBeijing 100081China Department of mechanical and Mechatronics engineering University of WaterlooWaterlooON N2L 3G1Canada School of Civil engineering Tsinghua UniversityBeijing 100084China

The new energy vehicle plays a crucial role in green transportation,and the energy management strategy of hybrid power systems is essential for ensuring energy-efficient *** paper presents a state-of-the-art survey and review of reinforcement learning-based energy management strategies for hybrid power ***,it envisions the outlook for autonomous intelligent hybrid electric vehicles,with reinforcement learning as the foundational *** of all,to provide a macro view of historical development,the brief history of deep learning,reinforcement learning,and deep reinforcement learning is presented in the form of a ***,the comprehensive survey and review are conducted by collecting papers from mainstream academic *** most of the contributions based on three main directions—algorithm innovation,powertrain innovation,and environment innovation—provides an objective review of the research ***,to advance the application of reinforcement learning in autonomous intelligent hybrid electric vehicles,future research plans positioned as“Alpha HEV”are envisioned,integrating Autopilot and energy-saving control.

关键词： New energy vehicle Hybrid power system Reinforcement learning energy management strategy

Effect of surface passivation on optical and electronic properties of ultrathin silicon nanosheets

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Science china(Information Sciences) 2012年第6期55卷 1469-1474页

作者： WANG Le 1,2,WU Ke 2,DONG QianMin 1,li XiaoYan 1,XIONG SiYu 1,XU LeiTing 3 & liANG Pei 1 1 college Of Electronic Science and engineering,china Jiliang university,hangzhou 310018,china 2 Department of engineering,zhejiang university,hangzhou 310000,china 3 Hang Zhou Urban Infrastructure Construction and Development Center,hangzhou 310000,china college Of Electronic Science and engineering China Jiliang University Hangzhou China Department of engineering Zhejiang University Hangzhou China Hang Zhou Urban Infrastructure Construction and Development Center Hangzhou China

The binding energy,electronic structure and optical properties of H-,H 3 C-,and HS-cluster-passivated ultrathin silicon (single-layer and double-layer) nanosheets were calculated using density functional theory based on the plane-wave ultra-soft ***,the most stable configuration was selected from passivated configurations according to the principle of lowest energy after calculating their total *** the density of state and the band structure of the different passivated systems were *** was found that different passivation clusters could affect the forbidden band,theremore the passivated cluster with sulfur could greatly decrease the width of the forbidden band through electron ***,the light absorption and reflection properties were also *** results were conducive to the development of silicon-based optoelectronic devices.

关键词： density functional theory surface passivation super-thin silicon nanosheets electronic structure

Porous framework materials for energy&environment relevant applications:A systematic review

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Green energy & Environment 2024年第2期9卷 217-310页

作者： Yutao liu liyu Chen lifeng Yang Tianhao Lan Hui Wang Chenghong Hu Xue Han Qixing liu Jianfa Chen Zeming Feng Xili Cui Qianrong Fang Hailong Wang libo li Yingwei li Huabin Xing Sihai Yang Dan Zhao Jinping li college of Chemical engineering and Technology Shanxi Key Laboratory of Gas Energy Efficient and Clean UtilizationTaiyuan University of TechnologyTaiyuan030024China School of Chemistry and Chemical engineering South China University of TechnologyGuangzhou510640China Key Laboratory of Biomass Chemical engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China Department of Chemistry The University of ManchesterManchesterM139PLUK Department of Chemical and Biomolecular engineering National University of SingaporeSingapore 117585Singapore ZJU-hangzhou Global Scientific and Technological Innovation Center Hangzhou311215China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun130012China Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of ChemistryUniversity of Science and Technology BeijingBeijing100083China

Carbon peaking and carbon neutralization trigger a technical revolution in energy&environment related *** of new technologies for green energy production and storage,industrial energy saving and efficiency reinforcement,carbon capture,and pollutant gas treatment is in highly imperious *** emerging porous framework materials such as metal–organic frameworks(MOFs),covalent organic frameworks(COFs)and hydrogen-bonded organic frameworks(HOFs),owing to the permanent porosity,tremendous specific surface area,designable structure and customizable functionality,have shown great potential in major energy-consuming industrial processes,including sustainable energy gas catalytic conversion,energy-efficient industrial gas separation and ***,this manuscript presents a systematic review of porous framework materials for global and comprehensive energy&environment related applications,from a macroscopic and application perspective.

关键词： Porous framework materials Catalysis Separation Gas storage Carbon neutrality

Lean methane combustion over zeolite-supported Pd catalysts:Structure-performance relationship and deactivation mechanism

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Journal of Environmental Sciences 2024年第11期145卷 128-138页

作者： Xingyu liu Jingkun Chen Bowen Han Renna li Le Shi Zhongbiao Wu Xiaole Weng Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China ZJU-hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311200China zhejiang Provincial engineering Research Centre of Industrial Boiler&Furnace Flue Gas Pollution Control Hangzhou 310058China

Zeolites are a promising support for Pd catalysts in leanmethane(CH_(4))***,three types of zeolites(H-MOR,H-ZSM-5 and H-Y)were selected to estimate their structural effects and deactivation mechanisms in CH_(4)*** show that variations in zeolite structure and surface acidity led to distinct changes in Pd ***/H-MOR with external high-dispersing Pd nanoparticles exhibited the best apparent activity,with activation energy(Ea)at 73 kJ/mol,while Pd/H-ZSM-5 displayed the highest turnover frequency(TOF)at 19.6×10^(−3)sec^(−1),presumably owing to its large particles with more step sites providing active sites in one particle for CH_(4)***/H-Y with dispersed PdO within pore channels and/or Pd2+ions on ion-exchange sites yielded the lowest apparent activity and ***,Pd/H-MOR and Pd/H-ZSM-5 were both stable under a dry condition,but introducing 3 vol.%H_(2)O caused the CH_(4)conversion rate on Pd/H-MOR drop from 100%to 63%and that on Pd/H-ZSM-5 decreased remarkably from 82%to 36%.The former was shown to originate fromzeolite structural dealumination,and the latter principally owed to Pd aggregation and the loss of active PdO.

关键词： Methane combustion Pd catalysts Zeolite Structure-performance relationship Deactivation mechanism

Climate chamber investigation of the effect of indoor thermal histories on thermal adaptation in different seasons

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energy and Built Environment 2024年第3期5卷 455-463页

作者： Yuxin Wu Angchen Jiang Hong liu Baizhan li Risto Kosonen School of Civil engineering and Architecture Zhejiang Sci-Tech UniversityHangzhouZhejiang 310018China Joint International Research Laboratory of Green Buildings and Built Environments(Ministry of Education) Chongqing UniversityChongqing 400045China National Centre for International Research of Low-carbon and Green Buildings(Ministry of Science and Technology) Chongqing UniversityChongqing 400045China Department of mechanical engineering Aalto UniversityEspoo 02150Finland college of Urban Construction Nanjing Tech UniversityNanjing 210009China

The indoor thermal history of residents in the hot summer and cold winter climate zone in china have undergone a significant change in recent years,which also changes their seasonal thermal adaptations and this has formed feed-back effects to the increasing usage of air conditioning units in this *** study the seasonal variations of thermal adaptation,the thermal comfort experiments were conducted on two groups of *** groups included 20 participants who had indoor history mainly with natural ventilation(NV group)and air-conditioning(AC group),*** results demonstrated that the thermal sensation vote(TSV)in warm environments did not differ between AC and NV subjects in ***,the TSV of AC subjects were much lower than that of NV subjects in the same standard effective temperature and skin temperature in a cold environment in ***,the participants who spent most of their time in AC space in winter showed a low level of thermal adaptation with a narrower acceptable skin temperature range of 32.6-33.5℃.Thus,this study presents the basic information regarding the seasonal effects on human thermal adaptation due to different long-term indoor thermal histories.

关键词： Skin temperature Thermal experience Thermal comfort Cold acclimation Hot summer and cold winter