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A review on the cooling of energy conversion and storage systems using thermoelectric modules
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作者 Amirreza IJADI Mehran Rajabi ZARGARABADI +1 位作者 Saman RASHIDI Amir Mohammad JADIDI 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期1998-2026,共29页
Exploitation of sustainable energy sources requires the use of unique conversion and storage systems,such as solar panels,batteries,fuel cells,and electronic equipment.Thermal load management of these energy conversio... Exploitation of sustainable energy sources requires the use of unique conversion and storage systems,such as solar panels,batteries,fuel cells,and electronic equipment.Thermal load management of these energy conversion and storage systems is one of their challenges and concerns.In this article,the thermal management of these systems using thermoelectric modules is reviewed.The results show that by choosing the right option to remove heat from the hot side of the thermoelectric modules,it will be a suitable local cooling,and the thermoelectric modules increase the power and lifespan of the system by reducing the spot temperature.Thermoelectric modules were effective in reducing panel temperature.They increase the time to reach a temperature above 50℃ in batteries by 3 to 4 times.Also,in their integration with fuel cells,they increase the power density of the fuel cell. 展开更多
关键词 COOLING PHOTOVOLTAIC lithium-ion batteries fuel cell electronic equipment thermoelectric modules
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Efficient and Stable Inverted Perovskite Solar Modules Enabled by Solid-Liquid Two-Step Film Formation
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作者 Juan Zhang Xiaofei Ji +13 位作者 Xiaoting Wang Liujiang Zhang Leyu Bi Zhenhuang Su Xingyu Gao Wenjun Zhang Lei Shi Guoqing Guan Abuliti Abudula Xiaogang Hao Liyou Yang Qiang Fu Alex K.‑Y.Jen Linfeng Lu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期571-582,共12页
A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells.The control of forming uniform and large-area film and perovskite crystallization is still the mai... A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells.The control of forming uniform and large-area film and perovskite crystallization is still the main obstacle restricting the efficiency of PSMs.In this work,we adopted a solid-liquid two-step film formation technique,which involved the evaporation of a lead iodide film and blade coating of an organic ammonium halide solution to prepare perovskite films.This method possesses the advantages of integrating vapor deposition and solution methods,which could apply to substrates with different roughness and avoid using toxic solvents to achieve a more uniform,large-area perovskite film.Furthermore,modification of the NiO_(x)/perovskite buried interface and introduction of Urea additives were utilized to reduce interface recombination and regulate perovskite crystallization.As a result,a large-area perovskite film possessing larger grains,fewer pinholes,and reduced defects could be achieved.The inverted PSM with an active area of 61.56 cm^(2)(10×10 cm^(2)substrate)achieved a champion power conversion efficiency of 20.56%and significantly improved stability.This method suggests an innovative approach to resolving the uniformity issue associated with large-area film fabrication. 展开更多
关键词 Inverted perovskite solar cells Perovskite solar modules Two-step film formation CRYSTALLIZATION Defect passivation
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Analysis of thermal management and anti-mechanical abuse of multi-functional battery modules based on magneto-sensitive shear thickening fluid
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作者 Yang XIONG Bo LU +1 位作者 Yicheng SONG Junqian ZHANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第3期529-542,共14页
Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cann... Electric vehicles(EVs)have garnered significant attention as a vital driver of economic growth and environmental sustainability.Nevertheless,ensuring the safety of high-energy batteries is now a top priority that cannot be overlooked during large-scale applications.This paper proposes an innovative active protection and cooling integrated battery module using smart materials,magneto-sensitive shear thickening fluid(MSTF),which is specifically designed to address safety threats posed by lithium-ion batteries(LIBs)exposed to harsh mechanical and environmental conditions.The theoretical framework introduces a novel approach for harnessing the smoothed-particle hydrodynamics(SPH)methodology that incorporates the intricate interplay of non-Newtonian fluid behavior,capturing the fluid-structure coupling inherent to the MSTF.This approach is further advanced by adopting an enhanced Herschel-Bulkley(H-B)model to encapsulate the intricate rheology of the MSTF under the influence of the magnetorheological effect(MRE)and shear thickening(ST)behavior.Numerical simulation results show that in the case of cooling,the MSTF is an effective cooling medium for rapidly reducing the temperature.In terms of mechanical abuse,the MSTF solidifies through actively applying the magnetic field during mechanical compression and impact within the battery module,resulting in 66%and 61.7%reductions in the maximum stress within the battery jellyroll,and 31.1%and 23%reductions in the reaction force,respectively.This mechanism effectively lowers the risk of short-circuit failure.The groundbreaking concepts unveiled in this paper for active protection battery modules are anticipated to be a valuable technological breakthrough in the areas of EV safety and lightweight/integrated design. 展开更多
关键词 magneto-sensitive shear thickening fluid(MSTF) battery module impact protection temperature control integrated design
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Research on the LA-UMamba Model for Asymmetric Modules with Added Auxiliary Information
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作者 YAN Jing SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期56-66,共11页
Deep learning techniques are revolutionizing the developmentof medical image segmentation.With the advancement of Transformer models,especially ViT and Swin-Transformer,which enhances the remote-dependent modeling cap... Deep learning techniques are revolutionizing the developmentof medical image segmentation.With the advancement of Transformer models,especially ViT and Swin-Transformer,which enhances the remote-dependent modeling capability of the model through the self-attention mechanism,better segmentation performance can be achieve.Moreover,the high computational cost of Transformer has motivated researchers to explore more efficient models,such as the Mamba model based on state-space modeling(SSM),and for the field of medical segmentation,reducing the number of model parameters is also necessary.In this study,a novel asymmetric model called LA-UMamba was proposed,which integrates visual Mamba module to efficiently capture complex visual features and remote dependencies.The classical design of U-Net was adopted in the upsampling phase to help reduce the number of references and recover more details.To mitigate the information loss problem,an auxiliary U-Net downsampling layer was designed to focus on sizing without extracting features,thus enhancing the protection of input information while maintaining the efficiency of the model.The experiments were conducted on the ACDC MRI cardiac segmentation dataset,and the results showed that the proposed LA-UMamba achieves proved performance compared to the baseline model in several evaluation metrics,such as IoU,Accuracy,Precision,HD and ASD,which improved that the model is successful in optimizing the detail processing and reducing the complexity of the model,providing a new perspective for further optimization of medical image segmentation techniques. 展开更多
关键词 Medical image segmentation U-Net Mamba module Deep Learning
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Study on Image Recognition Algorithm for Residual Snow and Ice on Photovoltaic Modules
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作者 Yongcan Zhu JiawenWang +3 位作者 Ye Zhang Long Zhao Botao Jiang Xinbo Huang 《Energy Engineering》 EI 2024年第4期895-911,共17页
The accumulation of snow and ice on PV modules can have a detrimental impact on power generation,leading to reduced efficiency for prolonged periods.Thus,it becomes imperative to develop an intelligent system capable ... The accumulation of snow and ice on PV modules can have a detrimental impact on power generation,leading to reduced efficiency for prolonged periods.Thus,it becomes imperative to develop an intelligent system capable of accurately assessing the extent of snow and ice coverage on PV modules.To address this issue,the article proposes an innovative ice and snow recognition algorithm that effectively segments the ice and snow areas within the collected images.Furthermore,the algorithm incorporates an analysis of the morphological characteristics of ice and snow coverage on PV modules,allowing for the establishment of a residual ice and snow recognition process.This process utilizes both the external ellipse method and the pixel statistical method to refine the identification process.The effectiveness of the proposed algorithm is validated through extensive testing with isolated and continuous snow area pictures.The results demonstrate the algorithm’s accuracy and reliability in identifying and quantifying residual snow and ice on PV modules.In conclusion,this research presents a valuable method for accurately detecting and quantifying snow and ice coverage on PV modules.This breakthrough is of utmost significance for PV power plants,as it enables predictions of power generation efficiency and facilitates efficient PV maintenance during the challenging winter conditions characterized by snow and ice.By proactively managing snow and ice coverage,PV power plants can optimize energy production and minimize downtime,ensuring a sustainable and reliable renewable energy supply. 展开更多
关键词 Photovoltaic(PV)module residual snow and ice snow detection feature extraction image processing
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Analysis for Effects of Temperature Rise of PV Modules upon Driving Distance of Vehicle Integrated Photovoltaic Electric Vehicles
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作者 Masafumi Yamaguchi Yasuyuki Ota +18 位作者 Taizo Masuda Christian Thiel Anastasios Tsakalidis Arnulf Jaeger-Waldau Kenji Araki Kensuke Nishioka Tatsuya Takamoto Takashi Nakado Kazumi Yamada Tsutomu Tanimoto Yosuke Tomita Yusuke Zushi Kenichi Okumura Takashi Mabuchi Akinori Satou Kyotaro Nakamura Ryo Ozaki Nobuaki Kojima Yoshio Ohshita 《Energy and Power Engineering》 2024年第4期131-150,共20页
The development of vehicle integrated photovoltaics-powered electric vehicles (VIPV-EV) significantly reduces CO<sub>2</sub> emissions from the transport sector to realize a decarbonized society. Although ... The development of vehicle integrated photovoltaics-powered electric vehicles (VIPV-EV) significantly reduces CO<sub>2</sub> emissions from the transport sector to realize a decarbonized society. Although long-distance driving of VIPV-EV without electricity charging is expected in sunny regions, driving distance of VIPV-EV is affected by climate conditions such as solar irradiation and temperature rise of PV modules. In this paper, detailed analytical results for effects of climate conditions such as solar irradiation and temperature rise of PV modules upon driving distance of the VIPV-EV were presented by using test data for Toyota Prius and Nissan Van demonstration cars installed with high-efficiency InGaP/GaAs/InGaAs 3-junction solar cell modules with a module efficiency of more than 30%. The temperature rise of some PV modules studied in this study was shown to be expressed by some coefficients related to solar irradiation, wind speed and radiative cooling. The potential of VIPV-EV to be deployed in 10 major cities was also analyzed. Although sunshine cities such as Phoenix show the high reduction ratio of driving range with 17% due to temperature rise of VIPV modules, populous cities such as Tokyo show low reduction ratio of 9%. It was also shown in this paper that the difference between the driving distance of VIPV-EV driving in the morning and the afternoon is due to PV modules’ radiative cooling. In addition, the importance of heat dissipation of PV modules and the development of high-efficiency PV modules with better temperature coefficients was suggested in order to expand driving range of VIPV-EV. The effects of air-conditioner usage and partial shading in addition to the effects of temperature rise of VIPV modules were suggested as the other power losses of VIPV-EV. 展开更多
关键词 Vehicle Integrated Photovoltaics (VIPV) VIPV-Powered Electric Vehicles Driving Distance PV modules Solar Irradiation Temperature Rise Radiative Cooling
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Solvent engineering towards scalable fabrication of high-quality perovskite films for efficient solar modules 被引量:4
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作者 Zhaoyi Jiang Binkai Wang +10 位作者 Wenjun Zhang Zhichun Yang Mengjie Li Fumeng Ren Tahir Imran Zhenxing Sun Shasha Zhang Yiqiang Zhang Zhiguo Zhao Zonghao Liu Wei Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第5期689-710,I0015,共23页
Over the last decade,remarkable progress has been made in metal halide perovskite solar cells(PSCs),which have been a focus of emerging photovoltaic techniques and show great potential for commercialization.However,th... Over the last decade,remarkable progress has been made in metal halide perovskite solar cells(PSCs),which have been a focus of emerging photovoltaic techniques and show great potential for commercialization.However,the upscaling of small-area PSCs to large-area solar modules to meet the demands of practical applications remains a significant challenge.The scalable production of high-quality perovskite films by a simple,reproducible process is crucial for resolving this issue.Furthermore,the crystallization behavior in the solution-processed fabrication of perovskite films can be strongly influenced by the physicochemical properties of the precursor inks,which are significantly affected by the employed solvents and their interactions with the solutes.Thus,a comprehensive understanding of solvent engineering for fabricating perovskite films over large areas is urgently required.In this paper,we first analyze the role of solvents in the solution-processed fabrication of large-area perovskite films based on the classical crystal nucleation and growth mechanism.Recent efforts in solvent engineering to improve the quality of perovskite films for solar modules are discussed.Finally,the basic principles and future challenges of solvent system design for scalable fabrication of high-quality perovskite films for efficient solar modules are proposed. 展开更多
关键词 Solvent engineering Scalable fabrication Perovskite film Solar cell Module
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Sandwich structured ultra-strong-heat-shielding aerogel/copper composite insulation board for safe lithium-ion batteries modules 被引量:2
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作者 Heng Yu Xiaowei Mu +7 位作者 Yulu Zhu Can Liao Longfei Han Jingwen Wang Wei Cai Yongchun Kan Lei Song Yuan Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期438-447,I0011,共11页
The fire hazard of lithium-ion batteries(LIBs)modules is extremely serious due to their high capacity.Moreover,once a battery catches fire,it can easily result in a fire of the entire LIBs modules.In this work,a sandw... The fire hazard of lithium-ion batteries(LIBs)modules is extremely serious due to their high capacity.Moreover,once a battery catches fire,it can easily result in a fire of the entire LIBs modules.In this work,a sandwich structure composite thermal insulation(STI)board(copper//silica dioxide aerogel//copper)with the advantages of low thermal conductivity(0.031 W m-1K-1),low surface radiation emissivity(0.1)and good thermal convection inhibition effect has been designed.The thermal runaway(TR)occurrence time of adjacent LIBs increases from 1384 s to more than 6 h+due to the protection of STI board.No TR propagation occurs within LIBs modules with protect of a STI board when a battery catches fire.The ultra-strong-heat-shielding mechanism of STI board has been revealed.The TR propagation of LIBs modules has been insulated effectively by STI board through reducing the heat transfer of convection,conduction and radiation.The air flow rate between the heater and LIBs and radiant heat absorbed by LIBs decrease by 63.5%and 35.1%with protection of STI board,respectively.A high temperature difference inside the STI board is also formed.This work provides direction for the designing of safe thermal insulation board for LIBs modules. 展开更多
关键词 Insulation board Ultra-strong-heat-shielding Lithium-ion battery modules Thermal runaway propagation Mechanism
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Highly Efficient and Stable FAPbI_(3) Perovskite Solar Cells and Modules Based on Exposure of the(011)Facet 被引量:2
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作者 Kai Zhang Bin Ding +12 位作者 Chenyue Wang Pengju Shi Xianfu Zhang Cheng Liu Yi Yang Xingyu Gao Rui Wang Li Tao Keith G.Brooks Songyuan Dai Paul J.Dyson Mohammad Khaja Nazeeruddin Yong Ding 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期164-174,共11页
Perovskite crystal facets greatly impact the performance and stability of their corresponding photovoltaic devices.Compared to the(001)facet,the(011)facet yields better photoelectric properties,including higher conduc... Perovskite crystal facets greatly impact the performance and stability of their corresponding photovoltaic devices.Compared to the(001)facet,the(011)facet yields better photoelectric properties,including higher conductivity and enhanced charge carrier mobility.Thus,achieving(011)facet-exposed films is a promising way to improve device performance.However,the growth of(011)facets is energetically unfavorable in FAPbI_(3) perovskites due to the influence of methylammonium chloride additive.Here,1-butyl-4-methylpyridinium chloride([4MBP]Cl)was used to expose(011)facets.The[4MBP]^(+)cation selectively decreases the surface energy of the(011)facet enabling the growth of the(011)plane.The[4MBP]^(+)cation causes the perovskite nuclei to rotate by 45°such that(011)crystal facets stack along the out-of-plane direction.The(011)facet has excellent charge transport properties and can achieve better-matched energy level alignment.In addition,[4MBP]Cl increases the activation energy barrier for ion migration,suppressing decomposition of the perovskite.As a result,a small-size device(0.06 cm2)and a module(29.0 cm2)based on exposure of the(011)facet achieved power conversion efficiencies of 25.24%and 21.12%,respectively. 展开更多
关键词 Renewable energy Perovskite solar cell Perovskite solar module Facet engineering
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Modulating J-V hysteresis of planar perovskite solar cells and mini-modules via work function engineering
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作者 Zenghua Wang Bing Cai +2 位作者 Deyu Xin Min Zhang Xiaojia Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期19-29,I0003,共12页
Commercialization of perovskite solar cells(PSCs) requires the development of high-efficiency devices with none current density-voltage(J-V) hysteresis. Here, electron transport layers(ETLs) with gradual change in wor... Commercialization of perovskite solar cells(PSCs) requires the development of high-efficiency devices with none current density-voltage(J-V) hysteresis. Here, electron transport layers(ETLs) with gradual change in work function(WF) are successfully fabricated and employed as an ideal model to investigate the energy barriers, charge transfer and recombination kinetics at ETL/perovskite interface. The energy barrier for electron injection existing at ETL/perovskite is directly assessed by surface photovoltage microscopy, and the results demonstrate the tunable barriers have significant impact on the J-V hysteresis and performance of PSCs. By work function engineering of ETL, PSCs exhibit PCEs over 21% with negligible hysteresis. These results provide a critical understanding of the origin reason for hysteresis effect in planar PSCs, and clear reveal that the J-V hysteresis can be effectively suppressed by carefully tuning the interface features in PSCs. By extending this strategy to a modified formamidinium-cesium-rubidium(FA-Cs-Rb) perovskite system, the PCEs are further boosted to 24.18%. Moreover, 5 cm × 5 cm perovskite mini-modules are also fabricated with an impressive efficiency of 20.07%, demonstrating compatibility and effectiveness of our strategy on upscaled devices. 展开更多
关键词 J-V hysteresis Work function Planar perovskite solar cells Energy barriers Charge transfer kinetics Perovskite solar modules
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Sodium Diffuses from Glass Substrates through P1 Lines and Passivates Defects in Perovskite Solar Modules
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作者 Felix Utama Kosasih Francesco Di Giacomo +13 位作者 Jordi Ferrer Orri Kexue Li Elizabeth M.Tennyson Weiwei Li Fabio Matteocci Gunnar Kusch Narges Yaghoobi Nia Rachel A.Oliver Judith L.MacManus-Driscoll Katie L.Moore Samuel D.Stranks Aldo Di Carlo Giorgio Divitini Caterina Ducati 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期393-401,共9页
Most thin-film photovoltaic modules are constructed on soda-lime glass(SLG)substrates containing alkali oxides,such as Na_(2)O.Na may diffuse from SLG into a module's active layers through P1 lines,an area between... Most thin-film photovoltaic modules are constructed on soda-lime glass(SLG)substrates containing alkali oxides,such as Na_(2)O.Na may diffuse from SLG into a module's active layers through P1 lines,an area between a module's constituent cells where the substrate-side charge transport layer(CTL)is in direct contact with SLG.Na diffusion from SLG is known to cause several important effects inⅡ-Ⅵand chalcogenide solar modules,but it has not been studied in perovskite solar modules(PSMs).In this work,we use complementary microscopy and spectroscopy techniques to show that Na diffusion occurs in the fabrication process of PSMs.Na diffuses vertically inside P1 lines and then laterally from P1 lines into the active area for up to 360 pm.We propose that this process is driven by the high temperatures the devices are exposed to during CTL and perovskite annealing.The diffused Na preferentially binds with Br,forming Br-poor,l-rich perovskite and a species rich in Na and Br(Na-Br)close to P1 lines.Na-Br passivates defect sites,reducing non-radiative recombination in the perovskite and boosting its luminescence by up to 5×.Na-Br is observed to be stable after 12 weeks of device storage,suggesting long-lasting effects of Na diffusion.Our results not only point to a potential avenue to increase PSM performance but also highlight the possibility of unabated Na diffusion throughout a module's lifetime,especially if accelerated by the electric field and elevated temperatures achievable during device operation. 展开更多
关键词 defect passivation monolithic interconnection perovskite solar modules soda-lime glass sodium diffusion solar cells thin-film photovoltaics
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Complement of the reduced non-zero component graph of free semimodules
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作者 T.Tamizh Chelvam K.Prabha Ananthi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第1期1-15,共15页
Let M be a finitely generated free semimodule over a semiring S with identity having invariant basis number property with a basisα={α1,...,αk}.The complement■of the reduced non-zero component graph■of M,is the si... Let M be a finitely generated free semimodule over a semiring S with identity having invariant basis number property with a basisα={α1,...,αk}.The complement■of the reduced non-zero component graph■of M,is the simple undirected graph with■as the vertex set and such that there is an edge between two distinct vertices■and■if and only if there exists no i such that both ai,biare non-zero.In this paper,we show that the graph■is connected and find its domination number,clique number and chromatic number.In the case of finite semirings,we determine the degree of each vertex,order,size,vertex connectivity and girth of■.Also,we give a necessary and sufficient condition for■to be Eulerian or Hamiltonian or planar. 展开更多
关键词 SEMIRING modules PLANAR
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Long-Chain Gemini Surfactant-Assisted Blade Coating Enables Large-Area Carbon-Based Perovskite Solar Modules with Record Performance
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作者 Yumin Ren Kai Zhang +5 位作者 Zedong Lin Xiaozhen Wei Man Xu Xianzhen Huang Haining Chen Shihe Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期463-477,共15页
Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in ambient air.However,scaling up to high-efficiency carbon-based solar modules hinges on reliable dep... Carbon-based perovskite solar cells show great potential owing to their low-cost production and superior stability in ambient air.However,scaling up to high-efficiency carbon-based solar modules hinges on reliable deposition of uniform defect-free perovskite films over large areas,which is an unsettled but urgent issue.In this work,a long-chain gemini surfactant is introduced into perovskite precursor ink to enforce self-assembly into a network structure,considerably enhancing the coverage and smoothness of the perovskite films.The long gemini surfactant plays a distinctively synergistic role in perovskite film construction,crystallization kinetics modulation and defect passivation,leading to a certified record power conversion efficiency of 15.46%with Voc of 1.13 V and Jsc of 22.92 mA cm^(-2)for this type of modules.Importantly,all of the functional layers of the module are printed through a simple and high-speed(300 cm min^(-1))blade coating strategy in ambient atmosphere.These results mark a significant step toward the commercialization of all-printable carbon-based perovskite solar modules. 展开更多
关键词 Long-chain gemini surfactant Blade-coating Capillary number Carbon-based perovskite photovoltaics All-printable module
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A Class of Simple Modules for Electrical Lie Algebra of Type D_(5)
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作者 陈雨露 申冉 张建刚 《Journal of Donghua University(English Edition)》 CAS 2023年第2期232-236,共5页
The simple modules for electrical Lie algebra of type D5 were investigated.The sufficient and necessary criteria of the simple Z-graded highest weight modules were established by means of determining the singular vect... The simple modules for electrical Lie algebra of type D5 were investigated.The sufficient and necessary criteria of the simple Z-graded highest weight modules were established by means of determining the singular vectors of the Verma modules.The simple highest weight module is isomorphic to either that for the symplectic Lie algebra sp4 or Verma module. 展开更多
关键词 electrical Lie algebra simple module highest weight module
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Relative Ding Projective Modules over Formal Triangular Matrix Rings
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作者 Hongyan Fan Xi Tang 《Journal of Applied Mathematics and Physics》 2023年第6期1598-1614,共17页
Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using t... Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using the left global relative Ding projective dimensions of A and B, we estimate the relative Ding projective dimension of a left T-module. 展开更多
关键词 Formal Triangular Matrix Ring Relative Ding Projective Module Relative Ding Projective Dimension
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基于YOLOv8-NFMC的带钢表面缺陷检测算法
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作者 朱成杰 刘乐乐 朱洪波 《国外电子测量技术》 2024年第7期97-104,共8页
针对YOLOv8算法在应用于带钢表面缺陷检测时存在漏检和错检等问题,提出了一种改进YOLOv8算法。针对数据集中的小目标的标签,在原损失CIOU的基础上面加入标准化高斯瓦瑟斯坦距离(normalized Gaussian Wasserstein distance,NWD),提升模... 针对YOLOv8算法在应用于带钢表面缺陷检测时存在漏检和错检等问题,提出了一种改进YOLOv8算法。针对数据集中的小目标的标签,在原损失CIOU的基础上面加入标准化高斯瓦瑟斯坦距离(normalized Gaussian Wasserstein distance,NWD),提升模型对小目标缺陷的检测能力;采用聚焦调制(focal modulation)替换YOLOv8模型的空间池化金字塔(spatial pyramid pooling-fast,SPPF),在轻量化的同时,提高多尺度特征的表达能力;采用移动翻转瓶颈卷积(mobile inverted bottleneck conv,MBConv)替换C2f中的Conv构建新模块C2f-MB,同时使用C2f-MB替换原有的C2f模块,增强特征表达能力和多尺度特征融合能力;在主干部分加入卷积块注意力机制(convolutional block attention module,CBAM)来抑制背景干扰,能更好捕获全局信息,提升了主干部分的特征提取能力。实验结果表明,改进后的YOLOv8算法在计算量下降的同时,mAP@0.5提高了3%,对漏检和错检等问题有明显改善。 展开更多
关键词 带钢表面缺陷 NWD Focal Modulation MBConv 注意力机制
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Design of Protograph LDPC-Coded MIMO-VLC Systems with Generalized Spatial Modulation 被引量:1
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作者 Dai Lin Fang Yi +1 位作者 Guan Yongliang Mohsen Guizani 《China Communications》 SCIE CSCD 2024年第3期118-136,共19页
This paper investigates the bit-interleaved coded generalized spatial modulation(BICGSM) with iterative decoding(BICGSM-ID) for multiple-input multiple-output(MIMO) visible light communications(VLC). In the BICGSM-ID ... This paper investigates the bit-interleaved coded generalized spatial modulation(BICGSM) with iterative decoding(BICGSM-ID) for multiple-input multiple-output(MIMO) visible light communications(VLC). In the BICGSM-ID scheme, the information bits conveyed by the signal-domain(SiD) symbols and the spatial-domain(SpD) light emitting diode(LED)-index patterns are coded by a protograph low-density parity-check(P-LDPC) code. Specifically, we propose a signal-domain symbol expanding and re-allocating(SSER) method for constructing a type of novel generalized spatial modulation(GSM) constellations, referred to as SSERGSM constellations, so as to boost the performance of the BICGSM-ID MIMO-VLC systems.Moreover, by applying a modified PEXIT(MPEXIT) algorithm, we further design a family of rate-compatible P-LDPC codes, referred to as enhanced accumulate-repeat-accumulate(EARA) codes,which possess both excellent decoding thresholds and linear-minimum-distance-growth property. Both analysis and simulation results illustrate that the proposed SSERGSM constellations and P-LDPC codes can remarkably improve the convergence and decoding performance of MIMO-VLC systems. Therefore, the proposed P-LDPC-coded SSERGSM-mapped BICGSMID configuration is envisioned as a promising transmission solution to satisfy the high-throughput requirement of MIMO-VLC applications. 展开更多
关键词 bit-interleaved coded modulation generalized spatial modulation multiple-input multipleoutput protograph LDPC codes visible light communication
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A Novel Multiple DBC-staked units Package to Parallel More Chips for SiC Power Module 被引量:1
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作者 Xiaoshuang Hui Puqi Ning +4 位作者 Tao Fan Yuhui Kang Kai Wang Yunhui Mei Guangyin Lei 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期72-79,共8页
Silicon carbide(SiC) power modules play an essential role in the electric vehicle drive system. To improve their performance, reduce their size, and increase production efficiency, this paper proposes a multiple stake... Silicon carbide(SiC) power modules play an essential role in the electric vehicle drive system. To improve their performance, reduce their size, and increase production efficiency, this paper proposes a multiple staked direct bonded copper(DBC) unit based power module packaging method to parallel more chips. This method utilizes mutual inductance cancellation effect to reduce parasitic inductance. Because the conduction area in the new package is doubled, the overall area of power module can be reduced. Entire power module is divided into smaller units to enhance manufacture yield, and improve design freedom. This paper provides a detailed design, analysis and fabrication procedure for the proposed package structure. Additionally, this paper offers several feasible solutions for the connection between power terminals and DBC untis. With the structure, 18dies were paralleled for each phase-leg in a econodual size power module. Both simulation and double pulse test results demonstrate that, compared to conventional layouts, the proposed package method has 74.8% smaller parasitic inductance and 34.9% lower footprint. 展开更多
关键词 Silicon carbide Electric vehicle Power modules PACKAGE
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High photoelectric conversion efficiency and fast relaxation time of FA_(0.4)MA_(0.6)PbI_(3) applied in ultrafast modulation of terahertz waves 被引量:1
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作者 Zhibo Xu Ying Zeng +5 位作者 Xinran Zhao Xiaoyin Chen Aoyu Fan Furi Ling Jiang Li Jianquan Yao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期299-305,共7页
Active control of terahertz(THz)waves is attracting tremendous attentions in terahertz communications and active photonic devices.Perovskite,due to its excellent photoelectric conversion performance and simple manufac... Active control of terahertz(THz)waves is attracting tremendous attentions in terahertz communications and active photonic devices.Perovskite,due to its excellent photoelectric conversion performance and simple manufacturing process,has emerged as a promising candidate for optoelectronic applications.However,the exploration of perovskites in optically controlled THz modulators is still limited.In this work,the photoelectric properties and carrier dynamics of FA_(0.4)MA_(0.6)PbI_(3)perovskite films were investigated by optical pumped terahertz probe(OPTP)system.The ultrafast carrier dynamics reveal that FA_(0.4)MA_(0.6)PbI_(3)thin film exhibits rapid switching and relaxation time within picosecond level,suggesting that FA_(0.4)MA_(0.6)PbI_(3)is an ideal candidate for active THz devices with ultrafast response.Furthermore,as a proof of concept,a FA_(0.4)MA_(0.6)PbI_(3)-based metadevice with integrating plasma-induced transparency(PIT)effect was fabricated to achieve ultrafast modulation of THz wave.The experimental results demonstrated that the switching time of FA_(0.4)MA_(0.6)PbI_(3)-based THz modulator is near to 3.5 ps,and the threshold of optical pump is as low as 12.7μJ cm^(-2).The simulation results attribute the mechanism of ultrafast THz modulation to photo-induced free carriers in the FA_(0.4)MA_(0.6)PbI_(3)layer,which progressively shorten the capacitive gap of PIT resonator.This study not only illuminates the potential of FA_(0.4)MA_(0.6)PbI_(3)in THz modulation,but also contributes to the field of ultrafast photonic devices. 展开更多
关键词 Terahertz modulation Perovskites METAMATERIALS Plasmon-induced transparency
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Bile acids,gut microbiota,and therapeutic insights in hepatocellular carcinoma 被引量:1
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作者 Yang Song Harry CH Lau +1 位作者 Xiang Zhang Jun Yu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第2期144-162,共19页
Hepatocellular carcinoma(HCC)is a prevalent and aggressive liver malignancy.The interplay between bile acids(BAs)and the gut microbiota has emerged as a critical factor in HCC development and progression.Under normal ... Hepatocellular carcinoma(HCC)is a prevalent and aggressive liver malignancy.The interplay between bile acids(BAs)and the gut microbiota has emerged as a critical factor in HCC development and progression.Under normal conditions,BA metabolism is tightly regulated through a bidirectional interplay between gut microorganisms and BAs.The gut microbiota plays a critical role in BA metabolism,and BAs are endogenous signaling molecules that help maintain liver and intestinal homeostasis.Of note,dysbiotic changes in the gut microbiota during pathogenesis and cancer development can disrupt BA homeostasis,thereby leading to liver inflammation and fibrosis,and ultimately contributing to HCC development.Therefore,understanding the intricate interplay between BAs and the gut microbiota is crucial for elucidating the mechanisms underlying hepatocarcinogenesis.In this review,we comprehensively explore the roles and functions of BA metabolism,with a focus on the interactions between BAs and gut microorganisms in HCC.Additionally,therapeutic strategies targeting BA metabolism and the gut microbiota are discussed,including the use of BA agonists/antagonists,probiotic/prebiotic and dietary interventions,fecal microbiota transplantation,and engineered bacteria.In summary,understanding the complex BA-microbiota crosstalk can provide valuable insights into HCC development and facilitate the development of innovative therapeutic approaches for liver malignancy. 展开更多
关键词 Bile acid gut microbiota hepatocellular carcinoma THERAPEUTICS microbiota modulation
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