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Frontiers of Structural and Civil Engineering 2023年第10期17卷 1535-1553页

作者： feng LI Rongrong ZHANG Siqi ZHOU Xingyi zhu School of Transportation Science and Engineering Beihang UniversityBeijing 100083China Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China

Using an in situ lunar regolith as a construction material in combination with 3D printing not only reduces the weight of materials carried from the Earth but also improves the automation of lunar infrastructure *** study aims to improve the printability of a geopolymer based on a BH-1 lunar regolith simulant,including the extrudability,open time,and buildability,by controlling the temperature and adding *** parameters were used to represent printability with different water-to-binder ratios,printing temperatures,and contents of *** mechanical properties of the hardening geopolymer with different filling paths and loading directions were *** results show that heating the printed filaments with a water-to-binder ratio of 0.32 at 80°C can adjust the printability without adding any additive,which can reduce the construction cost of lunar *** printability of the BH-1 geopolymer can also be improved by adding 0.3%Attagel-50 and 0.5%polypropylene fiber by mass at a temperature of 20℃to cope with the changeable environmental conditions on the *** curing under a simulated lunar environment,the 72-h flexural and compressive strengths of the geopolymer specimens reach 4.1 and 48.1 MPa,respectively,which are promising considering that the acceleration of gravity on the Moon is 1/6 of that on the Earth.

关键词： geopolymer lunar regolith simulant 3D printing rheology printability

High-efficiency crystalline white organic lightemitting diodes

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Light(Science & Applications) 2024年第4期13卷 747-759页

作者： Yijun Liu feng zhu Yue Wang Donghang Yan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China. School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China. State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China

Crystalline white organic light-emitting diodes(C-WOLEDs)are promising candidates for lighting and display *** is urgently necessary,however,to develop energy-saving and high-efficiency C-WOLEDs that have stable and powerful emission to meet commercial ***,we report a crystalline host matrix(CHM)with embedded nanoaggregates(NA)structure for developing high-performance C-WOLEDs by employing a thermally activated delayed fluorescence(TADF)material and orange phosphorescent dopants(Phos.-D).The CHM-TADFNA-D WOLED exhibit a remarkable EQE of 12.8%,which is the highest performance WOLEDs based on crystalline *** device has a quick formation of excitons and a well-designed energy transfer process,and possesses a fast ramping of luminance and current *** to recently reported high-performance WOLEDs based on amorphous material route,the C-WOLED achieves a low series-resistance Joule-heat loss ratio and an enhanced photon output,demonstrating its significant potential in developing the next-generation WOLEDs.

关键词： diodes dopant crystalline

Evaluation of transmission risk of respiratory particles under different ventilation strategies in an elevator

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Building Simulation 2024年第5期17卷 771-784页

作者： Liangyu zhu Xian Li Bujin feng Fan Liu School of Civil Engineering and Architecture Linyi UniversityLinyi276000China College of Agriculture Shandong Agricultural UniversityTaian271018China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

People in elevators are at risk of respiratory infection because the elevator cabin is crowded and has poor *** exhaled particles may be inhaled by the susceptible person,deposited on the surface and suspended in the elevator,which can result in direct and indirect ***,whether the air vent designs adopted in the elevator can effectively reduce the transmission risk of respiratory particles remains *** this study,the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by proven computational fluid dynamics(CFD)*** flow field was simulated with the RNG κ-ξ turbulence model and the Lagrangian method was adopted to track particle *** effects of air vent layout and airflow rate on particle transmission were *** found that more than 50% of exhaled particles(average value)were suspended in the cabin and difficult to discharge under the investigated ventilation *** deposited fraction of particles on the susceptible person reached up to 39.14% for infiltration ventilation,which led to a high risk of contact *** the ventilation rate could not significantly reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator.A more proper ventilation strategy should be explored for the elevator to control transmission risk.

关键词： particle dispersion transmission risk elevator ventilation strategy computational fluid dynamics(CFD)

Distributed Flocking Algorithm for Multi-UAV System Based on Behavior Method and Topological Communication

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Journal of Bionic Engineering 2023年第2期20卷 782-796页

作者： Yifei feng Jingshi Dong Jianlin Wang Hang zhu Key Laboratory of CNC Equipment Reliability Ministry of EducationSchool of Mechanical and Aerospace EngineeringJilin UniversityChangchun130025China Department of Mechanical Engineering The University of MelbourneMelbourneVIC3052Australia

There are many interesting flocking phenomena in nature,such as joint predation and group migration,and the intrinsic communication patterns of flocking are essential for studying group *** models of communication such as the pigeon flock model and the wolf pack model define all agents within a perceptual distance as the neighborhoods,and some models have fixed communicating *** is a significant impact on the quality of the flocking formation when encountering poor initial state of the flocking,multiple obstacles,or loss of certain *** solve this problem,this paper proposes a local communication model with nearest agents in four *** on this model and behavioral method,two distributed flocking formation algorithms are designed in this paper for different scenarios,namely the flocking algorithm and the circular formation *** simulation results show that the flocking can pass through the obstacle area and re-formation smoothly,and also the formation quality of the flocking is better compared with the traditional communication model.

关键词： Multi-UAV system Distributed control Flocking formation Topological communication Bioinspired

Synthesis and characterization of geopolymer from lunar regolith simulant based on natural volcanic scoria

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Chinese Journal of Aeronautics 2022年第1期35卷 144-159页

作者： Siqi ZHOU Xingyi zhu Chenghong LU feng LI School of Transportation Science and Engineering Beihang UniversityBeijing 100083China Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China

In this study,a new GVS(Ground Volcanic Scoria)lunar regolith simulant was *** similarity between GVS and lunar soil was proved by comparison with Apollo lunar soil samples and other commercial lunar soil ***,GVS lunar regolith simulant was investigated as the source material for preparing geopolymer to produce building material for lunar colony *** study the possibility of preparing geopolymer from GVS lunar regolith simulant and the optimum activator formulation as well as the optimum curing conditions,alkaline activated GVS slurries with different mixing ratios based on an orthogonal test scheme were *** geopolymer products based on GVS were characterized by flexural strength test,compressive strength test,X-ray fluorescence(XRF),X-ray diffraction(XRD),Fourier Transform Infrared Spectroscopy(FTIR),Scanning Electron Microscope coupled with Energy Dispersive Spectroscopy(SEM-EDS),29Si magic angle spinning-nuclear magnetic resonance(29Si MAS-NMR),and 27Al *** experimental results indicate that changes in the mass ratio of sodium hydroxide and GVS and curing temperature have the most significant influence on the flexural strength and compressive strength,*** GVS-based geopolymer can obtain the highest 28-day compressive strength and 28-day flexural strength up to 75.6 MPa and 6.3 *** results imply that the changes of Si occurring in a variety of environments that explaining preliminarily about the reaction mechanism of GVS-based *** study approves the feasibility of making a geopolymer derived from the GVS lunar regolith simulant and the potential utilization of geopolymer based on lunar regolith for construction of the lunar colony in future space exploration.

关键词： Geopolymer Lunar regolith simulant Mechanical properties Microstructure Moon colony Volcanic scoria

Solvent-free and catalyst-free method for the synthesis of 2,4,5-triarylimidazoles under microwave irradiation

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Chinese Chemical Letters 2009年第10期20卷 1198-1200页

作者： Jian feng Zhou Gui Xia Gong Hui Qin zhu feng Xia zhu a Department of Chemistry Huaiyin Teachers CollegeJiangsu Key Laboratory for Chemistry of Low-Dimensional Materials Huaian 223300 China School of Chemistry and Chemical Engineering Key Laboratory of Organic Synthesis of Jiangsu Province Suzhou University Suzhou 215123 China

A facile procedure for the synthesis of 2,4,5-lriarylimidazoles is being reported starting from benzil, aromatic aldehyde and ammonium acetate. The reactions were carried out with catalyst-free, solvent-free and under microwave irradiation conditions in high yield （80-99%） with short time （3-5 min） and environmental benign, as well as convenient operation. The structures of the compounds have been confirmed on the basis of their IR, 1H NMR, and/or 13C NMR, MS, and elemental analyzer.

关键词： Triarylimidazole Benzil Catalyst-free Solvent-free Microwave irradiation

Photodegradation of xylene isomers:Kinetics,mechanism,secondary pollutant formation potential and health risk evaluation

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Journal of Environmental Sciences 2024年第2期136卷 658-669页

作者： Xiaoyan Chen Weikun zhu Sufen feng Jiangyao Chen Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Photodegradation technology has been widely applied in the purification of industrial aromatic ***,whether this technology efficiently removes the pollutants to prevent secondary pollution and health risk is still ***,the photodegradation processes of three xylenes were compared under designed reaction atmospheres and light *** lamp showed poor photodegradation ability toward xylenes,no matter in N_(2) or N_(2)+O_(2)system,while much higher photodegradation performance of xylenes were obtained under ultraviolet(UV)and vacuum ultraviolet(VUV)irradiation,especially in N_(2)+O_(2)+VUV system,where 97.9%of m-xylene,99.0%of o-xylene or 87.5%of p-xylene with the initial concentration of 860 mg/m^(3) was removed within 240 *** xylenes underwent three processes of photo-isomerization,photodecomposition and photo-oxidation to produce intermediates of aromatics,alkanes and *** them,the photo-isomerization products showed the highest concentration percentage(e.g.,≥50%in o-xylene system),confirming that photo-isomerization reaction was the dominated photodegradation process of ***,these isomerized products not only contributed about 97%and91%to the formation potential of O3(OFP)and secondary organic aerosols(SOAFP),but also displayed obvious non-carcinogenic risk,although one of photodecomposition product—benzene showed the highest occupational exposure ***,the secondary pollution and health risks of photodegradation products of xylenes were non-ignorable,although the OFP,SOAFP and health risks of the generated products reduced at least 4.5 times in comparison with that of the degraded *** findings are helpful for the appropriate application of this technology in the purification of industrial organic waste gas.

关键词： Isomer aromatics Photodegradation Ozone formation Secondary organic aerosols Health risk

Effects of the microstructure of twin roll cast and hot rolled plates on the surface quality of presensitized plates

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International Journal of Minerals,Metallurgy and Materials 2014年第9期21卷 919-924页

作者： Yuan-Zhi zhu Ya-feng Zhang Chao-Qi Zhao feng Zhou College of Mechanical and Electrical Engineering North China University of Technology Key Laboratory for Ferrous Metallurgy and Resources Utilization of the Ministry of Education Wuhan University of Science and Technology

The effect of the microstructure of plates fabricated both in the traditional process, involving casting, hot rolling and cold rolling （HR）, and in the novel twin roll casting ＋ cold rolling （TRC） process on the surface quality of presensitized （PS） plates was analyzed by optical microscopy （OM）, scanning electron microscopy （SEM）, and energy-dispersive X-ray spectroscopy （EDXS）. The formation of pores on the surface of the electrolyzed HR plate could be attributed to the presence of approximately 1-μm-sized large Al-Fe precipitates in the HR plate compared to the smaller precipitates in the TRC plate. Moreover, residual graphite lubricants used during the TRC process were entrapped on the surface of the TRC plate during the subsequent rolling process. The entrapped pollutants tended to further deteriorate the formation of pores on the surface of the TRC plate, and no residual carbon was detected on the surface of the HR plate. Furthermore, the surface quality of the TRC plate can be improved by surface cleaning before the cold rolling process, which could dramatically lower the residual graphite on the surface.

关键词： aluminum plates microstructure presensitizing surface quality

Evaluation of Voltage Quality and Energy Saving Benefits of Urban Rail Transit Power Supply Systems Considering the Access of Photovoltaics

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2309-2320页

作者： Ding feng Hengkai zhu feng Wang Xiaojun Sun Sheng Lin Zhengyou He the School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China. China Railway Design Group Co. Ltd.Tianjin 300000China

Along the route of urban rail transit(URT),the subway depots,parking lots,and elevated subway stations are equipped with sufficient photovoltaic(PV)generation *** access of PVs in the URT power supply system should not only make full use of nearby renewable energy,but also improve the economic operation of the *** order to quantify the impact of PV access on the URT power supply system,this paper proposes a method to evaluate the voltage quality and energy saving benefits of the URT power supply system,considering PV ***,by fully considering the random fluctuations of PV output power,as well as the intermittency and impact of traction load,the URT power supply system with PV access is ***,such values as system voltage and power are calculated through the hybrid AC/DC load flow calculation *** with the results of the load flow calculation,the indicators describing voltage quality and power saving benefits of the system are proposed to quantify the influence of PV access on the ***,a case study concerning a certain section of a subway line is presented to verify the proposed *** shows that the proposed method can effectively quantify the voltage quality and power saving benefits of the system after PV access,providing valuable insights for design and maintenance personnel to comprehend system state and operating characteristics.

关键词： Energy saving benefits photovoltaics urban rail transit voltage quality

Anti-parity-time symmetric phase transition in diffusive systems

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Chinese Physics B 2021年第3期30卷 9-16页

作者： Pei-Chao Cao Xue-feng zhu School of Physics and Innovation Institute Huazhong University of Science and TechnologyWuhan 430074China

Parity-time (PT) symmetry/anti-parity-time (APT) symmetry in non-Hermitian systems reveal profound physics andspawn intriguing effects. Recently, it has been introduced into diffusive systems together with the concept of exceptionalpoints (EPs) from quantum mechanics and the wave systems. With the aid of convection, we can generate complex thermalconductivity and imitate various wavelike dynamics in heat transfer, where heat flow can be “stopped” or moving against thebackground motion. Non-Hermitian diffusive systems offer us a new platform to investigate the heat wave *** this review, we first introduce the construction of APT symmetry in a simple double-channel toy model. Then we showthe phase transition around the EP. Finally, we extend the double-channel model to the four-channel one for showing thehigh-order EP and the associated phase transition. In a general conclusion, the phase difference of adjacent channels isalways static in the APT symmetric phase, while it dynamically evolves or oscillates when the APT symmetry is broken.

关键词： anti-parity-time symmetry phase transition exceptional point heat transfer