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Microstructure and mechanical properties of nanobainitic steel subjected to multiple isothermal heat treatments

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Journal of Iron and Steel Research International 2018年第10期25卷 1062-1067页

作者： Ning Liu Xin Zhang Jing ding Jun He Fu-xing yin School of Material Science and Engineering and ResearchInstitute for Energy Equipment Materials Hebei Universityof Technology Tianjin 300130 China

Nanostructured bainite in 62MnSiCr steel was prepared by two-stage transformation process at different temperatures for less than 2 h. Microstructures, phase distribution and mechanical properties of the obtained steel were investigated. The results showed that the thickness of bainite plate and the amount of retained austenite decreased obviously after the twostage transformation, while the carbon concentration in the retained austenite showed a small change. With increase in the second holding temperature within the bainite transformation range, all of them increased slightly. The additional formation of bainite at the second transformation stage is beneficial to refining the austenite and further enriching it with carbon, resulting in the enhancement of the mechanical stability. Bainite transformed in two-stage process showed a better comprehensive performance. Absorbed impact energy of 88 J and an ultimate tensile strength of 1818 MPa have been achieved by isothermal heat treatment at 300 ℃ followed by 260 ℃. Meanwhile, there was a slight change in mechanical properties when the second transformation temperature varied from 260 to 220 ℃.

关键词： Nanostructured bainite Heat treatment Microstructure Mechanical property

Tracking and grasping of moving target based on accelerated geometric particle filter on colored image

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Science China(Technological Sciences) 2021年第4期64卷 755-766页

作者： GONG ZeYu QIU ChunRong TAO Bo BAI HaiSheng yin ZhouPing ding Han State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Visual tracking and grasping of moving object is a challenging task in the field of robotic manipulation,which also has great potential in applications such as human-robot *** on the particle filtering framework and position-based visual servoing,this paper proposes a new method for visual tracking and grasping of randomly moving objects.A geometric particle filter tracker is established for visual *** order to deal with the tracking efficiency issue for particle filter,edge detection and morphological dilation are employed to reduce the computation burden of geometric particle ***,the HSV image feature is employed instead of the grayscale feature to improve the tracking algorithm’s robustness to illumination change.A grasping strategy combining tracking and interception is adopted along with the position-based visual servoing(PBVS)method to achieve stable grasp of the *** comparisons on open source dataset and a large number of experiments on real robot system are conducted,which demonstrate the proposed method has competitive performance in random moving object tracking and grasping.

关键词： visual tracking robotic grasping geometric particle filtering visual servoing

A graph deep learning method for landslide displacement prediction based on global navigation satellite system positioning

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Geoscience Frontiers 2024年第1期15卷 29-38页

作者： Chuan Yang Yue yin Jiantong Zhang Penghui ding Jian Liu China Transport Telecommunications and Information Center Beijing 100011PR China China Nuclear Power Engineering Co. LtdBeijing 100011PR China

The accurate prediction of displacement is crucial for landslide deformation monitoring and early *** study focuses on a landslide in Wenzhou Belt Highway and proposes a novel multivariate landslide displacement prediction method that relies on graph deep learning and Global Navigation Satellite System(GNSS)*** model the graph structure of the monitoring system based on the engineering positions of the GNSS monitoring points and build the adjacent matrix of graph *** construct the historical and predicted time series feature matrixes using the processed temporal data including GNSS displacement,rainfall,groundwater table and soil moisture content and the graph *** introduce the state-of-the-art graph deep learning GTS(Graph for Time Series)model to improve the accuracy and reliability of landslide displacement prediction which utilizes the temporal-spatial dependency of the monitoring *** approach outperforms previous studies that only learned temporal features from a single monitoring point and maximally weighs the prediction performance and the priori graph of the monitoring *** proposed method performs better than SVM,XGBoost,LSTM and DCRNN models in terms of RMSE(1.35 mm),MAE(1.14 mm)and MAPE(0.25)evaluation metrics,which is provided to be effective in future landslide failure early warning.

关键词： Landslide displacement prediction GNSS positioning Graph deep learning

Photon subtraction-based continuous-variable measurement-device-independent quantum key distribution with discrete modulation over a fiber-to-water channel

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Communications in Theoretical Physics 2022年第3期74卷 36-43页

作者： Chao Yu yin Li Jianzhi ding Yun Mao ying Guo School of Computer Science and Engineering Central South UniversityChangsha 410083China School of Automation Central South UniversityChangsha 410075China School of Computer Science Beijing University of Posts and TelecommunicationsBeijing 100876China

We propose a discrete-modulated continuous-variable measurement-device-independent quantum key distribution protocol over a fiber-to-water *** from optical fibers,the underwater channel has more severe optical attenuation because of optical absorption and scattering,which reduces the maximum communication *** enhance the performance of the protocol,the photon subtraction operation is implemented at the modulator *** carry out a performance simulation in two different kinds of seawater channel,and the result shows that the scheme with photon subtraction has a longer secure communication distance under certain conditions.

关键词： measurement-device-independent discrete modulation fiber-to-water channel continuous variable quantum key distribution

Service-based Reliability Analysis of Integrated Electricity-heat Systems Considering Thermal Dynamics

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Journal of Modern Power Systems and Clean Energy 2023年第4期11卷 1176-1190页

作者： Xunhu yin Minglei Bao Yi ding Chengjin Ye Peng Wang Lalit Goel College of Electrical Engineering Zhejiang UniversityHangzhou 310027China Electrical and Electronic Engineering School Nanyang Technological UniversitySingapore 639798

The essential task of integrated electricity-heat systems(IEHSs)is to provide customers with reliable electric and heating *** the perspective of customers,it is reasonable to analyze the reliabilities of IEHSs based on the ability to provide energy services with a reasonable assurance of continuity and quality,which are termed as service-based *** to the thermal inertia existing in IEHSs,the heating service performances can present slow dynamic characteristics,which has a great impact on the service satisfaction of *** neglect of such thermal dynamics will bring about inaccurate service-based reliability measurement,which can lead to the inefficient dispatch decisions of system ***,it is necessary to provide a tool which can analyze the servicebased reliabilities of IEHSs considering the impacts of thermal *** paper firstly models the energy service performance of IEHSs in contingency ***,the nodal energy supplies are obtained from the optimal power and heat flow model under both variable hydraulic and thermal conditions,in which the transmission-side thermal dynamics are *** this basis,the energy service performances for customers are further determined with the formulation of demandside thermal ***,a service-based reliability analysis framework for the IEHSs is proposed utilizing the timesequential Monte Carlo simulation(TSMCS)technique with the embedded decomposition ***,the indices for quantifying service-based reliabilities are defined based on the traditional reliability indices,where dynamic service performances and service satisfactions of customers are both *** simulations are carried out with a test system to validate the effectiveness of the proposed framework.

关键词： Energy service integrated electricity-heat system reliability thermal dynamics

Highly π-extended copolymer as additive-free hole- transport material for perovskite solar cells

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Nano Research 2018年第1期11卷 185-194页

作者： Jie Liu Qianqing Ge Weifeng Zhang Jingyuan Ma Jie ding gui Yu Jinsong Hu Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CASResearch/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing100190 China University of Chinese Academy of Sciences Beijing 100049 China

Organolead halide perovskite solar ceils have achieved a certified power- conversion efficiency （PCE） of 22.1% and are thus among the most promising candidates for next-generation photovoltaic devices. To date, most high-efficiency perovskite solar cells have employed arylamine-based hole-transport materials （HTMs）, which are expensive and have a low mobility. The complicated doping procedures and the potentially stability-adverse dopants used in these HTMs are among the major bottlenecks for the commercialization of perovskite solar cells （PSCs）. Herein, we present a polythiophene-based copolymer （PDVT-10） with a hole mobility up to 8.2 cm2-V-l.s-1 and a highest occupied molecular orbital level of -5.28 eV as a hole-transport layer （HTL） for a PSC. A device based on this new HTM exhibited a high PCE of 13.4% under 100 mW-cm-2 illumination, which is one of the highest PCEs reported for the dopant-free polymer-based HTLs. Moreover, PDVT-10 exhibited good solution processability, decent air stability, and thermal stability, making it a promising candidate as an HTM for PSCs.

关键词： perovskite solar cell hole-transport layer dopant-free PDVT-IO stability

Heating Characteristics and Economic Analysis of a Controllable On-Demand Heating System Based on Off-Peak Electricity Energy Storage

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Journal of Thermal Science 2020年第2期29卷 343-351页

作者： yin Shaowu SHI Yongle TONG Lige LIU Chuanping WANG Li ding Yulong School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Energy Saving and Emission Reduction in Metallurgical Industry University of Science and Technology BeijingBeijing 100083China College of Chemical Engineering University of BirminghamBirmingham B152TTUK

The working principle of a controllable on-demand heating system based on off-peak electricity energy storage(COHSBOEES) is as follows: the cheap off-peak electricity energy is converted into heat energy for storage in the evening, and the heat energy can be extracted on demand for heating during daytime peak or flat electricity periods. This technology can promote the smooth operation of the power grid, solve the problem of peak regulation for the electrical network, and promote renewable energy consumption. Based on the controllable on-demand heating strategy, a COHSBOEES for a heating area of 1000 m^2 was designed and built. Variations in the energy consumption and operating cost of the COHSBOEES in different heating situations were analyzed. The results showed that, off-peak electricity energy storage for heating was energy saving in comparison with central heating when the heating intensity of the COHSBOEES was 70 W/m^2 and the on-demand heating rate was less than 73.0%, and the off-peak electricity energy storage for heating was energy saving at any on-demand heating rate when the COHSBOEES had a heating intensity of 50 W/m^2. After the COHSBOEES has been running for three complete heating seasons, when the off-peak electricity price was 0.25 yuan/kW·h, the energy consumption cost of the COHSBOEES can be saved by 77.6% in comparison with central heating.

关键词： energy storage on-demand heating off-peak electricity heating characteristics heat storage characteristics

Nickel-Catalyzed Stereoselective Migratory Carboboration of 1,4-Cyclohexadiene

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Chinese Journal of Chemistry 2024年第4期42卷 356-362页

作者： Yaoyu Ren Lujin Wang Chao ding Yangyang Li Guoyin yin The Institute for Advanced Studies Wuhan UniversityWuhanHubei430072 China

Multi-substituted cyclohexanes play a crucial role as scaffolds in bioactive *** significant progress has been made in synthesizing substituted cyclohexanes,methods for the stereoselective assembly of 1,3-disubstituted cyclohexanes remain *** study presents a novel approach involving nickel catalysis to achieve stereoselective carboboration of 1,*** innovative process allows for the simultaneous introduction of a boron group and an aryl or an alkyl fragment into the 1,4-cyclohexadiene framework under mild conditions,with exclusive regioselectivity and excellent cis *** resulting products feature a double carbon bond and the incorporation of the boron group,offering significant potential for subsequent transformations and downstream applications.

关键词： 1,4-Cyclohexadiene Carboboration Nickel Chain-walking Stereoselectivity Difunctionalization

Particle size distribution in a granular bed filter

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Particuology 2021年第5期19卷 108-117页

作者： Jianping Du Chuanping Liu Shaowu yin Ali Rehman Yulong ding Li Wang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Energy Saving and Emission Reduction in Metallurgical IndustryUniversity of Science and Technology BeijingBeijing 100083China Birmingham Centre for Energy Storage&School of Chemical Engineering University of BirminghamEdgbastonBirmingham B152TTUK

The effects of the filtering granule particle size and filtration superficial velocity on the dust particle size distribution in different layers of a granular bed system are discussed herein.A multilayer drawer granular bed filtration system was designed for these experiments based on filtering fly ash from a power *** a 1-h experiment,47.8% of dust particles smaller than 2.5μm,63.7% of dust particles smaller than 10μm,and 39.1% of dust particles larger than 10μm were captured by the granular bed(corresponding to initial volume fractions of 6%,19.3%,and 80.7%,respectively).Large dust particles were more easily trapped by the granular bed than small dust *** the size of the filter granules and increasing the superficial velocity of the inlet flue gas were both effective ways to enhance the dust-holding capacity of the granular media throughout the granular bed.

关键词： Granular bed Multilayer filtration Particle size distribution Filtration superficial velocity