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CSEE Journal of Power and energy Systems 2021年第2期7卷 318-328页

作者： Farzaneh Shojaei Mohammad Rastegar Morteza Dabbaghjamanesh Department of Power and Control Engineering School of Electrical and Computer EngineeringShiraz UniversityShirazIran Electrical and Computer Engineering Department The University of Texas at DallasUSA.

This study proposes a new method which aims to optimally install tie-lines and distributed generations *** is done to optimize the post-outage reconfiguration and minimize energy losses and energy not supplied of distribution *** number and location of tie-lines,as well as the number,size,and location of DGs,are pinpointed through teaching the learning-based optimization(TLBO)*** objective function in the current research is to minimize the costs pertaining to the investment,operation,energy losses,and energies not *** addition to the normal operational condition,fault operational condition is also ***,the optimal post-fault reconfigurations for fault occurrences in all lines are ***,the operational constraints such as the voltage and line current limits are taken into account in both normal and post-fault operational ***,the modified IEEE 33-bus and 69-bus distribution test systems are selected and tested to demonstrate the effectiveness of the simultaneous placement of DGs and tie-line technique proposed in this paper.

关键词： Distribution system reliability distributed generation energy loss post-outage reconfiguration tie-lines

Polymerized A-DA'D-A type small-molecule acceptors for high performance all-polymer solar cells: progress and perspective

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Science China Chemistry 2023年第9期66卷 2513-2531页

作者： Ting Yang Chuanlang Zhan Key Laboratory of Advanced Materials Chemistry and Devices(AMC&DLab)of the Department of Education of Inner Mongolia Autonomous Region College of Chemistry and Environmental ScienceInner Mongolia Normal UniversityHuhhot 010022China

A-DA'D-A type polymerized small-molecule acceptors(PSMAs) have very recently received wide attention because they possess advantages such as synthetic flexibility, narrowed bandgap, low energy loss, and impressive mechanical properties. With efforts on design and synthesis of PSMAs and polymer donors, significant progress has been made on all polymer solar cells(allPSCs) with power conversion efficiencies exceeding 18%. In this review, we focus on structure-property-performance relationships of the A-DA'D-A type PSMAs. First, we in-depth review the regio-random, regio-regular, and random ternary series by focusing on their structural modification such as from aspects of side-chains, halogenation, selenophene-containing and linkers, respectively. Second, we review the mechanically flexible and stretchable properties, which helps to find structural gene that correlates the mechanical properties. Third, we review the impressive small energy loss. In all, this review provides structural and material's clues, helpfully for designing high-performance all-PSCs.

关键词： all-polymer solar cell polymerized small-molecule acceptor regio-random regio-regular terpolymer energy loss

Classification and Comparison of Wave Impact Modes on Semi-Submersibles

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China Ocean Engineering 2021年第2期35卷 161-175页

作者： GUO Ying-hao XIAO Long-fei WEI Han-di LI Xin LI Lei DENG Yan-fei State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China SJTU-Sanya Yazhou Bay Institute of Deepsea Technology Hainan 572024China CIMC Offshore Co.Ltd. Shenzhen 518000China

Semi-submersibles for offshore oil exploration and exploitation often suffer from severe wave impacts in extreme ocean *** to the complex wave interactions among structural components of semi-submersibles,in-depth analyses on the characteristics of wave impact events are of significance for both industry and *** experimental study was carried out to investigate the local wave impact loads on a semi-submersible,with focus on understanding the wave impacts by identifying typical impact *** criteria are proposed to classify major wave impacts on the semi-submersible into six modes and two *** results show that the classification is reasonable and provides valuable information for studying wave impacts on *** incident wave characteristics at the fore column of the semi-submersible have important influence on the wave impact *** fore-column dominating wave impacts exert the most intense loads on the fore column and feature well-developed breaking waves or slightly breaking waves at the fore ***,the aft-column dominating wave impacts exert the most intense loads on the aft column or the deck bottom and feature non-breaking waves at the fore *** loss during the fore-column impact weakens the impact severity on the aft column in the fore-column dominating wave *** shoaling effect of the submerged pontoon and different motion configurations of the platform result in higher occurrence rate of the aft-column dominating wave *** impact modes are also distinguished by different spatial distributions of wave impact loads.

关键词： wave impact load semi-submersible wave breaking energy loss shoaling effect

Reduced energetic disorder enables over 14%efficiency in organic solar cells based on completely non-fused-ring donors and acceptors

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Science China Chemistry 2022年第12期65卷 2604-2612页

作者： Chenyi Yang Lijiao Ma Ye Xu Junzhen Ren Jianhui Hou Shaoqing Zhang School of Chemistry and Biology Engineering University of Science and Technology BeijingBeijing100083China State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing100190China

The large energetic disorder has been regarded as a limitation for the further advance of organic solar cells(OSCs).The intramolecular energetic disorder,which originates from the molecular conformational diversity,is quite different for various non-fused-ring materials and of great importance for the corresponding device *** this work,the 2-ethylhexyl on A4T-16,an efficient completely non-fused-ring acceptor,is replaced with the 3-ethylheptyl to obtain a novel acceptor of *** out-shifted branching position of 3-ethylheptyl reduces the steric hindrance effect,endowing A4T-3 with a more coplanar *** a result,A4T-3 exhibits a lower intramolecular energetic disorder than A4T-16,leading to a more uniform surface-electrostatic potential(ESP)***,A4T-3 exhibits a smaller barrier for intramolecular electron transport and a higher electron ***,the lower ESP endows A4T-3 with reduced non-radiative energy loss when blending with the *** using PTVT-T as the donor,the A4T-3-based OSC exhibited comprehensively improved photovoltaic properties in comparison with the A4T-16-based one,delivering a high power conversion efficiency(PCE)of 14.26%.Notably,this is the first report of OSCs where both the donor and the acceptor are completely non-fused-ring *** to the material-only cost(MOC)evaluation,the cost of PTVT-T:A4T-3-based device is much lower than that of other high-performance OSCs,revealing the great potential of completely non-fused-ring photoactive materials for application-oriented OSCs.

关键词： completely non-fused-ring intramolecular energetic disorder charge transport energy loss low cost

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The development of A-DA’D-A type nonfullerene acceptors containing non-halogenated end groups

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Nano Research 2023年第12期16卷 12949-12961页

作者： Hongxing Liu Tingting Dai Jialing Zhou Helin Wang Qing Guo Qiang Guo Erjun Zhou Henan Institute of Advanced Technology School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450003China National Center for Nanoscience and Technology Beijing 100190China

Compared with perovskite solar cells and silicon solar cells,the excessive voltage loss(Vloss)becomes a stubborn stone that seriously hinders the further improvement of organic photovoltaic(OPV).Thus,many researchers focus on finding an effective material system to achieve high-performance OPVs with low *** recent 5 years,acceptor-donor-acceptor’-donor-acceptor(A-DA’D-A)type non-fullerene acceptors(NFAs)have attracted great attention because of their promising photovoltaic *** them,A-DA’D-A type NFAs containing non-halogenated end group(NHEG)exhibit the large potential to achieve high open-circuit voltage(VOC)for the state-of-the-art OPVs,because of high-lying molecular energy levels and decreasing *** this review,we systematically summarize the recent development of A-DA’D-A type NHEG-NFAs and the impact of different NHEGs on the optoelectronic properties as well as the photovoltaic *** addition,we especially analyze the Vloss of NHEG-NFAs in the binary and ternary OPV *** last,we provide perspectives on the further molecular design and future challenges for this kind of materials as well as suggested solutions.

关键词： non-halogenated end group high voltage non-fullerene acceptor organic photovoltaic energy loss

Prediction of Coefficient of Restitution for Impact Elastoplastic Spheres Considering Finite Plate Thickness

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 183-193页

作者： Yunfeng Fan Hao Wang Tao Zhou Limin Zou Zhinong Jiang Minghui Hu State Key Laboratory of High-end Compressor and System Technology Beijing University of Chemical TechnologyBeijing 100029China China Ship Research and Development Academy Beijing 100101China Key Lab of Engine Health Monitoring-Control and Networking of Ministry of Education Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of High-End Mechanical Equipment Health Monitoring and Self-Recovery Beijing University of Chemical TechnologyBeijing 100029China

Collisions between objects are a relatively common phenomenon in *** of collision processes can greatly contribute to solving problems such as impact-rub faults and particle *** coefficient of restitution is a critical parameter in the analysis of collision *** experiments have shown that the coefficient of restitution is closely related to the plate thickness,and the smaller the plate thickness,the more inaccurate the coefficient of restitution predicted by the existing model,which seriously affects the process of collision *** remedy this shortcoming,this paper proposes a plate thickness influence factor with the ratio of sphere diameter to plate thickness as the *** plate thickness influence factor can optimize the coefficient of restitution model to effectively predict the coefficient of restitution of impacting elastoplastic spheres with finite plate ***,the validity of the new model is verified using a large amount of experimental data.

关键词： Collision Coefficient of restitution energy loss Sphere

Nozzle Optimization for Water Jet Propulsion with A Positive Displacement Pump

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China Ocean Engineering 2014年第3期28卷 409-419页

作者：杨友胜谢迎春聂松林 College of Engineering Ocean University of China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology

In the water jet propulsion system with a positive displacement （PD） pump, the nozzle, which converts pressure energy into kinetic energy, is one of the key parts exerting great influence on the reactive thrust and the efficiency of the system due to its high working pressure and easily occurring cavitation characteristics. Based on the previous studies of the energy loss and the pressure distribution of different nozzles, a model of water jet reactive thrust, which fully takes the energy loss and the nozzle parameters into consideration, is developed to optimize the nozzle design. Experiments and simulations are carried out to investigate the reactive thrust and the conversion efficiency of cylindrical nozzles, conical nozzles and optimized nozzles. The results show that the optimized nozzles have the largest reactive thrust and the highest energy conversion efficiency under the same inlet conditions. The related methods and conclusions are extended to the study of other applications of the water jet, such as water jet cutting, water mist fire suppression, water injection molding.

关键词： energy loss nozzle PD pump reactive thrust waterjet propulsion

Propagation and Amplitude Decay Mechanisms of Internal Solitary Waves

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China Ocean Engineering 2016年第6期30卷 979-991页

作者：王玲玲王春凌唐洪武陈红 State Key Laboratory of Hydrology- Water Resources and Hydraulic Engineering Nanjing 210008 China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210029 China

In this paper, a modified dynamic coherent eddy model （DCEM） of large eddy simulation is applied to study internal solitary waves in a numerical flume. The model was verified by physical experiment and applied to investigate the potential influence factors on internal wave amplitude. In addition, we discussed the energy loss of internal solitary wave as well as hydrodynamics in the propagation. The results of our study show that （1） Step-depth is the most sensitive factor on wave amplitude for the ＂step-pool＂ internal wave generation method and the wave amplitudes obey a linear increase with step depth, and the increase rate is about 0.4. （2） Wave energy loss obeys a linear decrease with the propagation distance and its loss rate of large amplitude waves is smaller than that of small amplitude waves. （3） loss of kinetic energy in wave valley is larger than that near the interface due to relative high fluctuating frequency. （4） Discovered boundary jet-flow can intensify the bottom shear, which might be one of the mechanisms of substance transportation, and the boundary layers of jet flows are easily influenced by the adjacent waves.

关键词： numerical wave flume internal solitary wave amplitude energy loss

Modeling and Analysis of Mechanical Quality Factor of the Resonator for Cylinder Vibratory Gyroscope

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Chinese Journal of Mechanical Engineering 2017年第1期30卷 180-189页

作者： XI Xiang WU Xuezhong WU Yulie ZHANG Yongmeng College of Mechatronics Engineering and Automation National University of Defense TechnologyChangsha 410073China

Mechanical Quality factor（Q factor） of the resonator is an important parameter for the cylinder vibratory gyroscope（CVG）. Traditional analytical methods mainly focus on a partial energy loss during the vibration process of the CVG resonator, thus are not accurate for the mechanical Q factor prediction. Therefore an integrated model including air damping loss, surface defect loss, support loss, thermoelastic damping loss and internal friction loss is proposed to obtain the mechanical Q factor of the CVG resonator. Based on structural dynamics and energy dissipation analysis, the contribution of each energy loss to the total mechanical Q factor is quantificationally analyzed. For the resonator with radius ranging from 10 mm to 20 mm, its mechanical Q factor is mainly related to the support loss, thermoelastic damping loss and internal friction loss, which are fundamentally determined by the geometric sizes and material properties of the resonator. In addition, resonators made of alloy 3J53 （Ni42CrTiA1）, with different sizes, were experimentally fabricated to test the mechanical Q factor. The theoretical model is well verified by the experimental data, thus provides an effective theoretical method to design and predict the mechanical Q factor of the CVG resonator.

关键词： mechanical Quality factor cylinder vibratory gyroscope energy loss

Improving performance of Cs_(2)AgBiBr_(6)solar cell through constructing gradient energy level with deep-level hole transport material

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Rare Metals 2023年第9期42卷 3004-3012页

作者： Zi-Yang Xia Wei Zhang Cheng Chen Hao-Xin Wang Lin-Qin Wang Ya-Wei Miao Xing-Dong Ding Li-Cheng Sun Ming Cheng Institute for energy Research School of Energy and Power EngineeringJiangsu UniversityZhenjiang212013China Center of Artificial Photosynthesis for Solar Fuels and Department of Chemistry School of ScienceWestlake UniversityHangzhou310024China

The valence band offset between Cs_(2)AgBiBr_(6)and hole transport layer(HTL)is approximately 1.00 e V,which results in high energy loss and is identified as one of the bottle necks of Cs_(2)Ag BiBr_(6)perovskite solar cell(PSC)for achieving high power conversion efficiency(PCE).To tackle this problem,we propose the optimization of the energy level alignment by designing and synthesizing novel deep-level hole transport materials(HTMs).The sole introduction of deep-level HTMs successfully reduces the valence band offset between Cs_(2)Ag Bi Br_(6)and HTL,but induces the increased valence band offset at HTL/Au interface,limiting the PCE *** further solve the problem and improve the PCE,the gradient energy level arrangement is constructed by combining the newly developed deep-level HTM 6,6’-(3-((9,9-dimethyl-9H-fluoren-3-yl)(4-methoxyphenyl)amino)thiophene-2,5-diyl)bis(N-(9,9-dimethyl-9H-fluoren-2-yl)-N,9-bis(4-methoxyphenyl)-9H-carbazol-3-amine)(TF)with 2,2’,7,7’-tetrakis(N,N’-dipmethoxyphenylamine)-9,9-spirobifluorene(Spiro-OMeTAD).Through optimization,an impressive PCE of 3.50%with remarkably high open-circuit voltage(V_(oc))and fill factor(FF)is achieved,qualifying it among the best pristine Cs_(2)AgBiBr_(6)PSCs.

关键词： All-inorganic Cs_(2)AgBiBr_(6)perovskite Stepped energy level structure energy loss Moisture resistance