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Initiation of Single-part Epoxy in Cementitious System

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Journal of Wuhan University of Technology(Materials science) 2016年第5期31卷 713-716页

作者：朱吉鹏 LI Zongjin ZHANG Yamei Department of Civil Engineering Nanjing University of Science&TechnologyNanjing 210094China Department of Civil Engineering The Hong Kong University of Science&TechnologyHong KongChina School of Materials science and Engineering Southeast UniversityNanjing 210096China

In order to make clear the interaction mechanism of single component epoxy in cementitious environment, the interaction between epoxy resin and active silanol, epoxy resin and alkali was investigated From solid-state 13C NMR and FT-IR tests, it is confirmed that silanol group can initiate epoxy resin. Test results have also revealed that alkali as the dominant product of cement hydration can open the epoxide ring making epoxy harden.

关键词： cementitious system epoxy hardener-free

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Identification of QTL for Popping Characteristics Using a BC_2F_2 Population and Comparison with Its F_(2:3) Population in Popcorn

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Agricultural sciences in china 2009年第2期8卷 137-143页

作者： LI Yu-ling DONG Yong-bin NIU Su-zhen CUI Dang-qun Agronomy College Henan Agricultural University Zhengzhou 450002 P.R.China

Normal corn germplasm can be used to improve popcorn （Zea mays L.） through 1-2 backcrosses with popcorn as recurrent parents. Popping characteristics of derived lines from popcorn × dent or flint corn crosses play a determinant role in popcorn breeding. Advanced backcross QTL methods can effectively combine QTL identification and plant breeding. 220 selected BC2F2 families developed from a cross between Dan 232, a dent corn inbred line, and N04, an elite popcorn inbred line, were evaluated for three popping characteristics, popping volume, flake size, and popping rate, under two environmental conditions. Using composite interval mapping, a total of 10 significant QTLs were detected, and of these, 2 to 4 QTLs were identified for each trait. Six QTLs had favorable alleles contributed by Dan 232. Comparison with the 15 QTLs detected in the F2：3 families showed that 3 QTLs were the same in both populations. The QTLs should be redetected in generations developed through severe selection. Improved N04 and near isogenic lines could be developed from this BC2F2 population through selfing or another 1 to 2 backcrosses with N04.

关键词： Zea mays L. popcorn BC2F2 population quantitative trait loci popping characteristics

MADDPG-D2: An Intelligent Dynamic Task Allocation Algorithm Based on Multi-Agent Architecture Driven by Prior Knowledge

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Computer Modeling in Engineering & sciences 2024年第9期140卷 2559-2586页

作者： Tengda Li Gang Wang Qiang Fu College of Air and Missile Defense Air Force Engineering UniversityXi’an710051China

Aiming at the problems of low solution accuracy and high decision pressure when facing large-scale dynamic task allocation(DTA)and high-dimensional decision space with single agent,this paper combines the deep reinforce-ment learning(DRL)theory and an improved Multi-Agent Deep Deterministic Policy Gradient(MADDPG-D2)algorithm with a dual experience replay pool and a dual noise based on multi-agent architecture is proposed to improve the efficiency of *** algorithm is based on the traditional Multi-Agent Deep Deterministic Policy Gradient(MADDPG)algorithm,and considers the introduction of a double noise mechanism to increase the action exploration space in the early stage of the algorithm,and the introduction of a double experience pool to improve the data utilization rate;at the same time,in order to accelerate the training speed and efficiency of the agents,and to solve the cold-start problem of the training,the a priori knowledge technology is applied to the training of the ***,the MADDPG-D2 algorithm is compared and analyzed based on the digital battlefield of ground and air *** experimental results show that the agents trained by the MADDPG-D2 algorithm have higher win rates and average rewards,can utilize the resources more reasonably,and better solve the problem of the traditional single agent algorithms facing the difficulty of solving the problem in the high-dimensional decision *** MADDPG-D2 algorithm based on multi-agent architecture proposed in this paper has certain superiority and rationality in DTA.

关键词： Deep reinforcement learning dynamic task allocation intelligent decision-making multi-agent system MADDPG-D2 algorithm

Particle mixing behavior of fine coal in density control of gas-solid separation fluidized bed

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Particuology 2020年第3期18卷 76-87页

作者： Bo Lv Zhenfu Luo Yanhong Fu Bo Zhang Xingzong Qin Xiangnan Zhu College of Chemistry and Chemical Engineering Henan Polytechnic UniversityJiaozuo 454000China Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education China University of Mining&TechnologyXuzhou 221116China School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou 221116China School of Chemical&Environmental Engineering Shandong University of Science&TechnologyQingdao 266590China

In a gas-solid separation fluidized bed,mixing of fine coal is necessary to achieve a suitable bed density to enable effective separation of low rank *** the basis of a variety of mixture models,a gas-solid separation fluidized bed was judged,where fine coal particles of 0.6-1.0mm were uniformly mixed with magnetite ***-speed dynamic camera technology was combined with a slump-sampling method to study the mixing process of the fine coal in the fluidized *** results showed that limitations of the fluidized bed structure cause the mixing process to be dominated by lateral diffusion and supplemented by axial *** diffusion was mainly achieved through the ascension of bubbles,whereas lateral diffusion was determined by the bursting action of the gas bubbles at the surface of the bed and the undulating characteristics of the *** effective lateral diffusion coefficient increased exponentially with gas velocity but had no strong relationship with the bed *** the feed point moved toward the center,fine coal began to diffuse to both sides,which shortened the time for the bed density stabilization from 20 to 5 *** bed density of the layer was stabilized at approximately 1.75 g/*** separation efficiency of the gas-solid separation fluidized bed containing binary mixtures was more obvious for 6-50 mm raw coal,with a probable error E of 0.16.

关键词： Gas-solid separation fluidized bed Density control Fine coal Diffusion behavior Separation process

Component Exergy Analysis of Solar Powered Transcritical CO_2 Rankine Cycle System

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Journal of Thermal science 2011年第3期20卷 195-200页

作者： Xiaojuan Li Xinrong Zhang Department of Energy and Resources Engineering College of Engineering Peking University Beijing 100871 China Department of Mechanical Engineering Doshisha University Kyoto 630-0321 Japan

In this paper,exergy analysis method is developed to assess a Rankine cycle system,by using supercritical CO2 as working fluid and powered by solar *** proposed system consists of evacuated solar collectors,throttling valve,high-temperature heat exchanger,low-temperature heat exchanger,and feed *** system is designed for utilize evacuated solar collectors to convert solar energy into mechanical energy and hence *** order to investigate and estimate exergy performance of this system,the energy,entropy,exergy balances are developed for the *** exergy destructions and exergy efficiency values of the system components are also *** results indicate that solar collector and high temperature heat exchanger which have low exergy efficiencies contribute the largest share to system irreversibility and should be the optimization design focus to improve system exergy ***,exergy analysis is a useful tool in this regard as it permits the performance of each process to be assessed and losses to be *** analysis results can be used in design,optimization,and improvement efforts.

关键词： Transcritical CO2 Rankine cycle Solar energy Solar collector Component exergy analysis

Research on a combinatorial control method for coaxial rotor aircraft based on sliding mode

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Defence Technology（防务技术） 2022年第2期18卷 280-292页

作者： Yi-ran Wei Hong-bin Deng Zhen-hua Pan Ke-wei Li Han Chen School of Mechatronical Engineering Beijing Institute of TechnologyBeijingChina School of Automation Beijing Institute of TechnologyBeijingChina Beijing Institute of Computer and Electronics Application BeijingChina Hong Kong Polytechnic University Hong KongChina

Aiming at the position and attitude tracking of coaxial rotor aircraft(CRA),this paper proposes a combinatorial control method of sliding mode control(SMC)coupled with proportional-integralderivative control(PIDC).Considering the complete description of flight dynamics,aerodynamics and airflow interference,the dynamical model of CRA is *** dynamical model is simplified according to the actual flight,then the simplified dynamical model is divided into two subsystems:a fully-actuated subsystem and an under-actuated *** controller of the fully-actuated subsystem consists of a SMC controller coupled with a rate bounded PIDC controller,while the controller of the under-actuated subsystem is composed of a SMC *** sliding manifold is defined by combining the position and velocity tracking errors of the state variables for each *** stability theory is used to verify the stability of the sliding mode controller,which ensures that all state trajectories of the system can reach and stay on the sliding mode surface,the uncertainty and external interference of the model are *** and experiment compared with the conventional PIDC are carried out,the results demonstrate the effectiveness and the robustness of the proposed control method of this paper.

关键词： Coaxial rotor aircraft Sliding mode control Position and attitude tracking Simulation Experiment

Complex coordinated functional groups: A great genes for nonlinear optical materials

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Chinese Chemical Letters 2022年第5期33卷 2301-2315页

作者： Weikang Wang Dajiang Mei Shaoguo Wen Jian Wang Yuandong Wu College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China Department of Chemistry and Biochemistry Wichita State UniversityWichitaKS 67260United States State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Complex coordinated functional groups[MA_(x)B_(y)](M=Central coordination element;A,B=P,O,S,Se,F,Cl,Br or I)are composed of different types of anions A,B jointly linked to the same central cation M,which are in high potential to tune the physical properties of materials,e.g.,second-order susceptibility,energy gaps and ***,Compound containing complex coordinated functional groups have attracted great attention in the nonlinear optical(NLO)field and a large number of this type crystals exhibit promising NLO ***,the inherent relationship between ionic group structure and optical properties of complex coordinated NLO materials have not been systematically *** article systematically summarizes complex coordinated NLO materials in recent five years from the perspective of the internal relationship between crystal structure and optical *** addition,we propose the ideal combination and arrangement modes for structural building units,and also reveal the influence of complex coordinated functional groups[MA_(x)B_(y)]toward the NLO response,optical band gap and phase matching ability of complex coordinated NLO materials.

关键词： Complex coordinated Nonlinear optical Second harmonic generation Optical band gap Structure-performance relationship

Low-dimensional MXenes as noble metal-free co-catalyst for solar-to-fuel production:Progress and prospects

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Journal of Materials science & Technology 2022年第19期114卷 143-164页

作者： Wanying Lei Tong Zhou Xin Pang Shixiang Xue Quanlong Xu College of Materials science and Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Key laboratory of Carbon Materials of Zhejiang Province Wenzhou UniversityWenzhou 325027China

Direct conversion of solar energy into chemical fuels via semiconducting materials through photocatalytic technology is a sustainable way to tackle the global warming, environmental issue and energy crisis. Transition metal carbides and nitrides(MXenes), a newly emerging class of 2D layered materials, has gained tremendous attention as a noble metal-free co-catalyst for boosting photoreactivity due to its extraordinary characteristics like elemental abundance, excellent electrical conductivity, abundant surface functional groups, unique hydrophilic behavior and flexible modulation of chemical composition. The rational integration of low-dimensional MXenes in the form of 2D layered structures or 0D quantum dots with diverse semiconducting materials offer more versatile and robust heterostructured-photocatalysts that are applicable in solar fuel generation. Herein, we summarize the recent advances and achievements in the synthesis of low-dimensional MXenes and their application in hydrogen production from water splitting and CO_(2) photoreduction. A comprehensive discussion of the fundamentals for solar fuel production, synthesis strategies and theoretical calculations for MXenes-based photocatalysts are also given. Finally, the existing challenges and further perspectives of MXenes-based nanostructures for efficient solar fuel production are addressed.

关键词： MXenes Low-dimensional materials Co-catalyst Photocatalytic H_(2)evolution CO_(2)photoreduction

STUDY ON CONTROL STRATEGY OF CLUTCH STARTING FOR CAR WITH A METAL PUSHING BELT-PLANETARY GEAR CONTINUOUSLY VARIABLE TRANSMISSION SYSTEM

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 43-47页

作者： Sun Dongye Qin Datong Wang Hongyan State Key Laboratory of Mechanical Transmission, Chongqing University, Chongqing 400044,china Chongqing University State Key Laboratory of Mechanical Transmission 重庆 400044

The automatic control of clutch starting in car with a metal pushingbelt-planetary gear continuously variable transmission (CVT) is a complex problem. A suited controlstrategy is required to realize quick and smooth start. A simulation state space equation isestablished on clutch staring control of a car with CVT by bond graph theory. According to the fuzzycontrol method with the expert system, a fuzzy control system of car starting process to weaken thejerk motion is introduced. The simulation results indicate that the jerk motion of clutch startingis below 10 m/s^3.

关键词： Car Continuously variable transmission Clutch Control