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黏土矿物包壳对砂岩储层质量的影响:基于多相场的数值模拟实验
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作者 KUMAR Akash SPÄTH Michael +4 位作者 PRAJAPATI Nishant BUSCH Benjamin SCHNEIDER Daniel HILGERS Christoph NESTLER Britta 《石油勘探与开发》 北大核心 2025年第3期638-652,共15页
石英颗粒表面的黏土包壳是决定砂岩储层孔隙度和渗透率大小的关键因素,直接影响碎屑岩储层质量。基于共轴石英胶结的多相场模型,通过数值模拟实验研究黏土包壳参数对砂岩储层中石英胶结量、孔隙度、渗透率及其相互关系的影响。研究主要... 石英颗粒表面的黏土包壳是决定砂岩储层孔隙度和渗透率大小的关键因素,直接影响碎屑岩储层质量。基于共轴石英胶结的多相场模型,通过数值模拟实验研究黏土包壳参数对砂岩储层中石英胶结量、孔隙度、渗透率及其相互关系的影响。研究主要取得5项进展:①为了在三维数字砂岩模型的石英颗粒上模拟出逼近实际的各种黏土包壳形态,研发了一套新的预处理工作流程。②分别对发育石英单颗粒和多颗粒的砂岩开展共轴生长胶结的数值模拟实验,揭示出控制石英胶结量的主要包壳参数,即暴露锥面的生长方向、包壳覆盖率和包壳形态等。③黏土包壳形态对胶结具有显著影响,其中层状包壳形态的胶结速度较快;包壳覆盖率与砂岩孔隙度和渗透率呈正相关关系。④石英颗粒结晶垂直方向上胶结物生长速度最小,演化中后期斜角方向生长速度较水平方向更快。⑤动态演化过程模拟结果与实际对比验证显示,20,40 d后的包壳形态模拟结果与天然样品中观察到的形态高度相似,证实了包壳三维数值建模新方法的有效性。该套黏土包壳数值模拟方法和研究成果有助于改进砂岩储层表征结果和预测模型。 展开更多
关键词 石英胶结 黏土矿物包壳 颗粒包壳 相场建模 砂岩 储层质量 石英次生加大
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The wearable landscape: Issues pertaining to the validation of the measurement of 24-h physical activity, sedentary, and sleep behavior assessment 被引量:2
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作者 Marco Giurgiu Birte von Haaren-Mack +16 位作者 Janis Fiedler Simon Woll Alexander Burchartz Simon Kolb Sascha Ketelhut Claudia Kubica Carina Nigg Irina Timm Maximiliane Thron Steffen Schmidt Kathrin Wunsch Gerhard Muller Claudio RNigg Alexander Woll Markus Reichert Ulrich Ebner-Priemer Johannes BJ Bussmann 《Journal of Sport and Health Science》 2025年第3期131-139,共9页
The ongoing revolution in information technology is reshaping human life. In the realm of health behavior, wearable technology emerges as a leading digital solution,capturing physical behaviors (i.e., physical activit... The ongoing revolution in information technology is reshaping human life. In the realm of health behavior, wearable technology emerges as a leading digital solution,capturing physical behaviors (i.e., physical activity, sedentary habits, sleep patterns) within the 24-h cycle of daily life. Wearables are applied in research, clinical practice, and as lifestyle devices;most obvious, they promise to be a key element for increasing human physical activity, one of the biggest health challenges nowadays. 展开更多
关键词 increasing human physical activityone lifestyle devicesmost validation studies health behaviorwearable technology revolution information technology wearable technology physical activity physical behaviors iephysical
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A Genetic Algorithm Approach for Location-Specific Calibration of Rainfed Maize Cropping in the Context of Smallholder Farming in West Africa
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作者 Moussa Waongo Patrick Laux +2 位作者 Jan Bliefernicht Amadou Coulibaly Seydou B. Traore 《Agricultural Sciences》 2025年第1期89-111,共23页
Smallholder farming in West Africa faces various challenges, such as limited access to seeds, fertilizers, modern mechanization, and agricultural climate services. Crop productivity obtained under these conditions var... Smallholder farming in West Africa faces various challenges, such as limited access to seeds, fertilizers, modern mechanization, and agricultural climate services. Crop productivity obtained under these conditions varies significantly from one farmer to another, making it challenging to accurately estimate crop production through crop models. This limitation has implications for the reliability of using crop models as agricultural decision-making support tools. To support decision making in agriculture, an approach combining a genetic algorithm (GA) with the crop model AquaCrop is proposed for a location-specific calibration of maize cropping. In this approach, AquaCrop is used to simulate maize crop yield while the GA is used to derive optimal parameters set at grid cell resolution from various combinations of cultivar parameters and crop management in the process of crop and management options calibration. Statistics on pairwise simulated and observed yields indicate that the coefficient of determination varies from 0.20 to 0.65, with a yield deviation ranging from 8% to 36% across Burkina Faso (BF). An analysis of the optimal parameter sets shows that regardless of the climatic zone, a base temperature of 10˚C and an upper temperature of 32˚C is observed in at least 50% of grid cells. The growing season length and the harvest index vary significantly across BF, with the highest values found in the Soudanian zone and the lowest values in the Sahelian zone. Regarding management strategies, the fertility mean rate is approximately 35%, 39%, and 49% for the Sahelian, Soudano-sahelian, and Soudanian zones, respectively. The mean weed cover is around 36%, with the Sahelian and Soudano-sahelian zones showing the highest variability. The proposed approach can be an alternative to the conventional one-size-fits-all approach commonly used for regional crop modeling. Moreover, it has the potential to explore the performance of cropping strategies to adapt to changing climate conditions. 展开更多
关键词 Smallholder Farming AquaCrop Genetics Algorithm Optimization MAIZE Burkina Faso
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Impact of clay coating on sandstone reservoir quality:A multiphase-field investigation by numerical simulation
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作者 KUMAR Akash SPÄH Michael +4 位作者 PRAJAPATI Nishant BUSCH Benjamin SCHNEIDER Daniel HILGERS Christoph NESTLER Britta 《Petroleum Exploration and Development》 2025年第3期715-730,共16页
The presence of clay coatings on the surfaces of quartz grains can play a pivotal role in determining the porosity and permeability of sandstone reservoirs,thus directly impacting their reservoir quality.This study em... The presence of clay coatings on the surfaces of quartz grains can play a pivotal role in determining the porosity and permeability of sandstone reservoirs,thus directly impacting their reservoir quality.This study employs a multiphase-field model of syntaxial quartz cementation to explore the effects of clay coatings on quartz cement volumes,porosity,permeability,and their interrelations in sandstone formations.To generate various patterns of clay coatings on quartz grains within three-dimensional(3D)digital sandstone grain packs,a pre-processing toolchain is developed.Through numerical simulation experiments involving syntaxial overgrowth cementation on both single crystals and multigrain packs,the main coating parameters controlling quartz cement volume are elucidated.Such parameters include the growth of exposed pyramidal faces,lateral encasement,coating coverage,and coating pattern,etc.The coating pattern has a remarkable impact on cementation,with the layered coatings corresponding to fast cement growth rates.The coating coverage is positively correlated with the porosity and permeability of sandstone.The cement growth rate of quartz crystals is the lowest in the vertical orientation,and in the middle to late stages of evolution,it is faster in the diagonal orientation than in the horizontal orientation.Through comparing the simulated results of dynamic evolution process with the actual features,it is found that the simulated coating patterns after 20 d and 40 d show clear similarities with natural samples,proving the validity of the proposed three-dimensional numerical modeling of coatings.The methodology and findings presented contribute to improved reservoir characterization and predictive modeling of sandstone formations. 展开更多
关键词 quartz cementation clay coating grain coating phase-field modeling SANDSTONE reservoir quality quartz overgrowth
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Origami-inspired perovskite X-ray detector by printing and folding
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作者 Henning Mescher Fabian Schackmar +11 位作者 Robert Huber Helge Eggers Marcus Zuber Elias Hamann Georg Gramlich Julian Dangelmaier Qiaoshuang Zhang Andres Georg Rösch Thomas Zwick Gerardo Hernandez-Sosa Ulrich W.Paetzold Uli Lemmer 《npj Flexible Electronics》 SCIE 2023年第1期471-478,共8页
X-ray detectors are of pivotal importance for the scientific and technological progress in a wide range of medical,industrial,and scientific applications.Here,we take advantage of the printability of perovskite-based ... X-ray detectors are of pivotal importance for the scientific and technological progress in a wide range of medical,industrial,and scientific applications.Here,we take advantage of the printability of perovskite-based semiconductors and achieve a high X-ray sensitivity combined with the potential of an exceptional high spatial resolution by our origami-inspired folded perovskite X-ray detector.The high performance of our device is reached solely by the folded detector architecture and does not require any photolithography.The design and fabrication of a foldable perovskite sensor array is presented and the detector is characterized as a planar and as a folded device.Exposed to 50 kVp−150 kVp X-ray radiation,the planar detector reaches X-ray sensitivities of 25−35μC/(Gyaircm^(2)),whereas the folded detector achieves remarkably increased X-ray sensitivities of several hundredμC/(Gyaircm^(2))and a record value of 1409μC/(Gyaircm^(2))at 150 kVp without photoconductive gain.Finally,the potential of an exceptional high spatial resolution of the folded detector of more than 20 lp/mm under 150 kVp X-ray radiation is demonstrated. 展开更多
关键词 PEROVSKITE exceptional PLANAR
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Synergistic enhancement of strength and plasticity in CoCrFeNiMn high-entropy alloys by novel core−shell microstructure design
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作者 Chong-yang LIU Xiao-song JIANG +2 位作者 Hong-liang SUN Zi-xuan WU Liu YANG 《Transactions of Nonferrous Metals Society of China》 2025年第10期3428-3442,共15页
The novel core−shell SiC@CoCrFeNiMn high-entropy alloy(HEA)matrix composites(SiC@HEA)were successfully prepared via mechanical ball milling and vacuum hot-pressing sintering(VHPS).After sintering,the microstructure wa... The novel core−shell SiC@CoCrFeNiMn high-entropy alloy(HEA)matrix composites(SiC@HEA)were successfully prepared via mechanical ball milling and vacuum hot-pressing sintering(VHPS).After sintering,the microstructure was composed of FCC solid solution,Cr_(23)C_(6) carbide phases,and Mn_(2)SiO_(4) oxy-silicon phase.The relative density,hardness,tensile strength,and elongation of SiC@HEA composites with 1.0 wt.%SiC were 98.5%,HV 358.0,712.3 MPa,and 36.2%,respectively.The core−shell structure had a significant deflecting effect on the cracks.This effect allowed the composites to effectively maintain the excellent plasticity of the matrix.As a result,the core−shell SiC@HEA composites obtained superior strength and plasticity with multiple mechanisms. 展开更多
关键词 high-entropy alloy SiC nanoparticles microstructure design core−shell structure tensile properties strength and plasticity synergy
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Efficient Resource Management in IoT Network through ACOGA Algorithm
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作者 Pravinkumar Bhujangrao Landge Yashpal Singh +1 位作者 Hitesh Mohapatra Seyyed Ahmad Edalatpanah 《Computer Modeling in Engineering & Sciences》 2025年第5期1661-1688,共28页
Internet of things networks often suffer from early node failures and short lifespan due to energy limits.Traditional routing methods are not enough.This work proposes a new hybrid algorithm called ACOGA.It combines A... Internet of things networks often suffer from early node failures and short lifespan due to energy limits.Traditional routing methods are not enough.This work proposes a new hybrid algorithm called ACOGA.It combines Ant Colony Optimization(ACO)and the Greedy Algorithm(GA).ACO finds smart paths while Greedy makes quick decisions.This improves energy use and performance.ACOGA outperforms Hybrid Energy-Efficient(HEE)and Adaptive Lossless Data Compression(ALDC)algorithms.After 500 rounds,only 5%of ACOGA’s nodes are dead,compared to 15%for HEE and 20%for ALDC.The network using ACOGA runs for 1200 rounds before the first nodes fail.HEE lasts 900 rounds and ALDC only 850.ACOGA saves at least 15%more energy by better distributing the load.It also achieves a 98%packet delivery rate.The method works well in mixed IoT networks like Smart Water Management Systems(SWMS).These systems have different power levels and communication ranges.The simulation of proposed model has been done in MATLAB simulator.The results show that that the proposed model outperform then the existing models. 展开更多
关键词 Energy management IoT networks ant colony optimization(ACO) greedy algorithm hybrid optimization routing algorithms energy efficiency network lifetime
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Crosslinked ionogels containing a Li-conducting inorganic phase as electrolyte for lithium-metal batteries
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作者 Matteo Gandolfo Mattia Longo +3 位作者 Thomas Diemant Silvia Bodoardo Dominic Bresser Julia Amici 《Journal of Energy Chemistry》 2025年第8期221-232,共12页
In the quest for the development of safer lithium-metal batteries(LMBs),the integration of inorganic fillers and ionic liquids into polymer matrices has emerged as a promising strategy to enhance safety,ionic conducti... In the quest for the development of safer lithium-metal batteries(LMBs),the integration of inorganic fillers and ionic liquids into polymer matrices has emerged as a promising strategy to enhance safety,ionic conductivity and battery performance.This study introduces a novel composite ionogel(IG)synthesized through a facile one-pot method,incorporating butyl methacrylate(BMA)and poly(ethylene glycol)diacrylate(PEGDA)with the ionic liquid 1-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide(PYR_(14)FSI)and garnet Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)nanoparticles.A distinctive feature of the approach is the use of an organosilane functionalization of the LLZTO nanoparticles,which ensures their full integration into the polymer matrix during free-radical polymerization.Moreover,this method effectively eliminates the Li_(2)CO_(3)passivation layer that typically forms on the surface of the LLZTO nanoparticles,thus,further contributing to an enhanced performance.As a result,a LMB with the functionalized LLZTO IG electrolyte delivered more than 160 mA h g^(−1)with a very good capacity retention of 97.7%after 400 cycles in Li|IG|LFP cells. 展开更多
关键词 Lithium-metal batteries lonogels Hybrid solid-state electrolytes Active fillers lonic liquids
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Interfacial processes of Mg anodes for magnesium-sulfur batteries:An EIS study
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作者 Joachim Häcker Tobias Rommel +5 位作者 Pia Lange Felix Kampmann Jürgen Remmlinger Zhirong Zhao-Karger K.Andreas Friedrich Maryam Nojabaee 《Journal of Magnesium and Alloys》 2025年第6期2680-2698,共19页
The development of magnesium batteries strongly relies on the use of a Mg metal anode and its benefits of high volumetric capacity,reduction potential,low cost and improved safety,however,to date,it still lacks suffic... The development of magnesium batteries strongly relies on the use of a Mg metal anode and its benefits of high volumetric capacity,reduction potential,low cost and improved safety,however,to date,it still lacks sufficient cycling stability and reversibility.Along with the electrolyte selection,the interfacial processes can be affected by the anode itself applying electrode engineering strategies.In this study,six different Mg anode approaches–namely bare Mg metal,Mg foil with an organic and inorganic artificial solid electrolyte interphase,Mg alloy,Mg pellet and a tape-casted Mg slurry–are selected to be investigated by means of electrochemical impedance spectroscopy in Mg|Mg and Mg|S cells.While a plating/stripping overpotential asymmetry was observed and assigned to the desolvation during Mg plating,the impedance spectra of stripping and plating hardly differ for all applied anodes.In contrast,the sulfur species significantly influence the impedance response by altering the surface layer composition.By systematic process assignment of the gained spectra in Mg|Mg and Mg|S cells,specific equivalent circuit models for different anodes and cell conditions are derived.Overall,the study aims to give valuable insights into the interfacial processes of Mg anodes to support their further development toward long-lasting Mg batteries. 展开更多
关键词 Magnesium anode Artificial solid electrolyte interphase Electrochemical impedance spectroscopy Equivalent circuit model Magnesium-sulfur battery
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Dielectric-ion-conductive ZnNb_(2)O_(6) layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries
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作者 Haifeng Yang Jian Wang +9 位作者 Panpan Zhang Xiaomin Cheng Qinghua Guan Jing Dong Bixian Chen Lujie Jia Jing Zhang Yongzheng Zhang Yunjian Liu Hongzhen Lin 《Journal of Energy Chemistry》 2025年第1期693-701,共9页
Rechargeable aqueous zinc-metal batteries (AZMBs) are promising candidates for large-scale energy storage systems due to their low cost and high safety.However,their performance and sustainability are significantly hi... Rechargeable aqueous zinc-metal batteries (AZMBs) are promising candidates for large-scale energy storage systems due to their low cost and high safety.However,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn(H_(2)O)_(6)^(2+)solvation shell.Herein,learnt from self-generated solid electrolyte interphase (SEI) in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface (ZNB@Zn),acting as a rapid desolvation promotor.The zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical calculations.Consequently,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility (99.54%) even under high current density and depth of discharge conditions.Meanwhile,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g^(-1)and outstanding rate performance up to 10 A g^(-1).The large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs. 展开更多
关键词 Zn metal battery Dielectri cartificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition
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Tailoring anion-dominant solvation environment by steric-hindrance effect and competitive coordination for fast charging and stable cycling lithium metal batteries
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作者 Ruizhe Xu Anjun Hu +7 位作者 Zhen Wang Kai Chen Jingze Chen Wang Xu Gang Wu Fei Li Jian Wang Jianping Long 《Journal of Energy Chemistry》 2025年第6期35-43,I0002,共10页
The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate elect... The properties of electrolytes are critical for fast-charging and stable-cycling applications in lithium metal batteries(LMBs).However,the slow kinetics of Li^(+)transport and desolvation in commercial carbonate electrolytes,cou pled with the formation of unstable solid electrolyte interphases(SEI),exacerbate the degradation of LMB performance at high current densities.Herein,we propose a versatile electrolyte design strategy that incorporates cyclohexyl methyl ether(CME)as a co-solvent to reshape the Li^(+)solvation environment by the steric-hindrance effect of bulky molecules and their competitive coordination with other solvent molecules.Simulation calculations and spectral analysis demonstrate that the addition of CME molecules reduces the involvement of other solvent molecules in the Li solvation sheath and promotes the formation of Li^(+)-PF_(6)^(-)coordination,thereby accelerating Li^(+)transport kinetics.Additionally,this electrolyte composition improves Li^(+)desolvation kinetics and fosters the formation of inorganic-rich SEI,ensuring cycle stability under fast charging.Consequently,the Li‖LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)battery with the modified electrolyte retains 82% of its initial capacity after 463 cycles at 1 C.Even under the extreme fast-charging condition of 5 C,the battery can maintain 80% capacity retention after 173 cycles.This work provides a promising approach for the development of highperformance LMBs by modulating solvation environment of electrolytes. 展开更多
关键词 Lithium metal batteries Fast charging Stable cycling Solvation structure
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Reducing Critical Raw Material Use in Commercial Solid Oxide Fuel Cells Using Vertically Aligned Thin-Film Cathodes with Enhanced Long-Term Stability
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作者 Matthew P.Wells Kosova Kreka +8 位作者 Mohana V.Kante Miriam Botros Ozden Celikbilek Jan Pieter Ouweltjes Federico Baiutti Simon M.Fairclough Caterina Ducati Albert Tarancon Judith L.MacManus-Driscoll 《Energy & Environmental Materials》 2025年第4期289-295,共7页
Solid oxide fuel cells(SOFCs)are widely presented as a sustainable solution to future energy challenges.Nevertheless,solid oxide fuel cells presently rely on significant use of several critical raw materials to enable... Solid oxide fuel cells(SOFCs)are widely presented as a sustainable solution to future energy challenges.Nevertheless,solid oxide fuel cells presently rely on significant use of several critical raw materials to enable optimized electrode reaction kinetics.This challenge can be addressed by using thinfilm electrode materials;however,this is typically accompanied by complex device fabrication procedures as well as poor mechanical/chemical stability.In this work,we conduct a systematic study of a range of promising thin-film electrode materials based on vertically aligned nanocomposite(VAN)thin films.We demonstrate low area specific resistance(ASR)values of 0.44 cm^(2) at 650℃ can be achieved using(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3)-(Sm_(2)O_(3))_(0.20)(CeO_(2))_(0.80)(LSCF-SDC)thin films,which are also characterized by a low degradation rate,approximately half that of planar LSCF thin films.We then integrate these(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3)-(Sm_(2)O_(3))_(0.20)(CeO_(2))_(0.80) vertically aligned nanocomposite films directly with commercial anode supported half cells through a single-step deposition process.The resulting cells exhibit peak power density of 0.47W cm^(-2) at 750℃,competitive with 0.64W cm^(-2) achieved for the same cells operating with a bulk(La_(0.60)Sr_(0.40))_(0.95)Co_(0.20)Fe_(0.80)O_(3) cathode,despite 99.5% reduction in cathode critical raw material use.By demonstrating such competitive performance using thin-film cathode functional layers,this work also paves the way for further cost reductions in solid oxide fuel cells,which could be achieved by likewise applying thin-film architectures to the anode functional layer and/or current collecting layers,which typically account for the greatest materials cost in solid oxide fuel cell stacks.Therefore,the present work marks a valuable step towards the sustainable proliferation of solid oxide fuel cells. 展开更多
关键词 solid oxide fuel cells thin films vertically aligned nanocomposites
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Tailoring solvation sheath for rechargeable zinc-ion batteries:Progress and prospect
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作者 Xiaomin Cheng Jing Dong +7 位作者 Haifeng Yang Xiang Li Xinyu Zhao Bixian Chen Yongzheng Zhang Meinan Liu Jian Wang Hongzhen Lin 《Materials Reports(Energy)》 2025年第1期3-18,共16页
Aqueous zinc-metal based batteries(AZMBs)perfectly combine safety,economy and pro-environment,but their performance is arresting limited by the interfacial instability caused by the large desolvation energy barrier of... Aqueous zinc-metal based batteries(AZMBs)perfectly combine safety,economy and pro-environment,but their performance is arresting limited by the interfacial instability caused by the large desolvation energy barrier of[Zn(H2O)6]^(2+)and the massive release of active water at the electrolyte/electrode interface.In this review,we briefly outline the solvation structure of zinc ions and the necessity of desolvation.Subsequently,the variety of strategies to solve these issues,mainly including reorganizing solvation sheath by changing electrolyte environment and accelerating interface desolvation by constructing artificial interfacial layer,are categorically discussed and systematically summarized.Meanwhile,perspectives and suggestions regarding desolvation theories,interfacial evolution,material design and analysis techniques are proposed to design highly stable zinc anodes. 展开更多
关键词 Aqueous zinc-metal based batteries DESOLVATION Electrolyte strategy Interfacial layer
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Stirring the hydrogen and butanol production from Enset fiber via simultaneous saccharification and fermentation(SSF)process 被引量:1
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作者 Nebyat Seid Lea Wießner +1 位作者 Habibu Aliyu Anke Neumann 《Bioresources and Bioprocessing》 2024年第1期1269-1287,共19页
Enset fiber is a promising feedstock for biofuel production with the potential to reduce carbon emissions and improve the sustainability of the energy system.This study aimed to maximize hydrogen and butanol productio... Enset fiber is a promising feedstock for biofuel production with the potential to reduce carbon emissions and improve the sustainability of the energy system.This study aimed to maximize hydrogen and butanol production from Enset fiber through simultaneous saccharification and fermentation(SSF)process in bottles as well as in bioreactor.The SSF process in bottles resulted in a higher butanol concentration of 11.36 g/L with a yield of 0.23 g/g and a productivity of 0.16 g/(L h)at the optimal process parameters of 5%(w/v)substrate loading,16 FPU/g cellulase loading,and 100 rpm agitation speed from pretreated Enset fiber.Moreover,a comparable result to the bottle experiment was observed in the bioreactor with pH-uncontrolled SSF process,although with a decreased in butanol productivity to 0.095 g/(L h).However,using the pre-hydrolysis simultaneous saccharification and fermentation(PSSF)process in the bioreactor with a 7%(w/v)substrate loading led to the highest butanol concentration of 12.84 g/L with a productivity of 0.104 g/(L h).Furthermore,optimizing the SSF process parameters to favor hydrogen resulted in an increased hydrogen yield of 198.27 mL/g-Enset fiber at atmospheric pressure,an initial pH of 8.0,and 37°C.In general,stirring the SSF process to shift the product ratio to either hydrogen or butanol was possible by adjusting temperature and pressure.At 37°C and atmospheric pressure,the process resulted in an e-mol yield of 12%for hydrogen and 38%for butanol.Alternatively,at 30°C and 0.55 bar overpressure,the process achieved a yield of 6%e-mol of hydrogen and 48%e-mol of butanol.This is the first study to produce hydrogen and butanol from Enset fiber using the SSF process and contributes to the development of a circular bioeconomy. 展开更多
关键词 HYDROGEN BUTANOL Enset fiber C.saccharoperbutylacetonicum SSF PSSF
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Non-crossing Quantile Regression Neural Network as a Calibration Tool for Ensemble Weather Forecasts 被引量:2
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作者 Mengmeng SONG Dazhi YANG +7 位作者 Sebastian LERCH Xiang'ao XIA Gokhan Mert YAGLI Jamie M.BRIGHT Yanbo SHEN Bai LIU Xingli LIU Martin Janos MAYER 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1417-1437,共21页
Despite the maturity of ensemble numerical weather prediction(NWP),the resulting forecasts are still,more often than not,under-dispersed.As such,forecast calibration tools have become popular.Among those tools,quantil... Despite the maturity of ensemble numerical weather prediction(NWP),the resulting forecasts are still,more often than not,under-dispersed.As such,forecast calibration tools have become popular.Among those tools,quantile regression(QR)is highly competitive in terms of both flexibility and predictive performance.Nevertheless,a long-standing problem of QR is quantile crossing,which greatly limits the interpretability of QR-calibrated forecasts.On this point,this study proposes a non-crossing quantile regression neural network(NCQRNN),for calibrating ensemble NWP forecasts into a set of reliable quantile forecasts without crossing.The overarching design principle of NCQRNN is to add on top of the conventional QRNN structure another hidden layer,which imposes a non-decreasing mapping between the combined output from nodes of the last hidden layer to the nodes of the output layer,through a triangular weight matrix with positive entries.The empirical part of the work considers a solar irradiance case study,in which four years of ensemble irradiance forecasts at seven locations,issued by the European Centre for Medium-Range Weather Forecasts,are calibrated via NCQRNN,as well as via an eclectic mix of benchmarking models,ranging from the naïve climatology to the state-of-the-art deep-learning and other non-crossing models.Formal and stringent forecast verification suggests that the forecasts post-processed via NCQRNN attain the maximum sharpness subject to calibration,amongst all competitors.Furthermore,the proposed conception to resolve quantile crossing is remarkably simple yet general,and thus has broad applicability as it can be integrated with many shallow-and deep-learning-based neural networks. 展开更多
关键词 ensemble weather forecasting forecast calibration non-crossing quantile regression neural network CORP reliability diagram POST-PROCESSING
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高强化柴油机铝活塞销孔开裂分析及改进 被引量:1
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作者 李倩 王志龙 +3 位作者 张俊青 王世利 王君 刘世英 《内燃机与动力装置》 2024年第1期64-70,共7页
基于失效机理分析某国六高强化柴油机铝活塞耐久试验中销孔开裂问题,发现活塞失效的主要原因为活塞销椭圆变形过大,导致销孔部位水平方向受力较大,疲劳强度不足。通过将活塞销孔由圆柱孔改为椭圆孔、在活塞销孔部位预留空间、将活塞销... 基于失效机理分析某国六高强化柴油机铝活塞耐久试验中销孔开裂问题,发现活塞失效的主要原因为活塞销椭圆变形过大,导致销孔部位水平方向受力较大,疲劳强度不足。通过将活塞销孔由圆柱孔改为椭圆孔、在活塞销孔部位预留空间、将活塞销内孔喇叭口改为通孔等措施对销孔结构进行改进,采用有限元分析软件对改进方案进行模拟计算,并结合销孔疲劳试验和耐久试验进行验证。结果表明:改进后的活塞销孔平均负载增加约6.5%,改进后未出现活塞销孔开裂问题。 展开更多
关键词 铝活塞 销孔开裂 有限元 试验验证
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满足国六排放标准的直列4缸轻型柴油机活塞销孔和活塞销设计 被引量:1
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作者 李倩 楚翔宇 +2 位作者 贾志勇 曹江鹏 李珂 《柴油机设计与制造》 2024年第2期13-18,共6页
针对轻型柴油机活塞销孔部位失效问题,设计4种满足国六排放标准的直列4缸轻型柴油机活塞销孔和活塞销方案。利用有限元分析软件对其进行模拟计算,对活塞销孔接触应力和疲劳,以及活塞销应变和疲劳进行比较;同时,为验证模拟分析的准确性,... 针对轻型柴油机活塞销孔部位失效问题,设计4种满足国六排放标准的直列4缸轻型柴油机活塞销孔和活塞销方案。利用有限元分析软件对其进行模拟计算,对活塞销孔接触应力和疲劳,以及活塞销应变和疲劳进行比较;同时,为验证模拟分析的准确性,根据实际情况对其中3种方案进行了销孔液压脉冲试验验证,试验结果与模拟结果吻合良好。设计方案可为高强化柴油机活塞和活塞销设计及失效改进提供参考. 展开更多
关键词 活塞销 活塞销孔 有限元分析 失效分析
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Comprehension-driven design of advanced multi-block single-ion conducting polymer electrolytes for high-performance lithium-metal batteries
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作者 Xu Dong Dominic Bresser 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期357-359,共3页
The continuously growing importance of batteries for powering(hybrid)electric vehicles and storing renewable energy has prompted a renewed focus on lithium-metal batteries(LMBs)in recent years,as its high theoretical ... The continuously growing importance of batteries for powering(hybrid)electric vehicles and storing renewable energy has prompted a renewed focus on lithium-metal batteries(LMBs)in recent years,as its high theoretical specific capacity of about 3860 mA h g^(-1) and very low redox potential(-3.04 V vs.the standard hydrogen electrode)promise substantially higher energy densities compared to current lithium-ion batteries(LIBs)[1].However,lithium metal electrodes face severe challenges associated with the risk of dendritic lithium deposition and the high reactivity with traditional organic liquid electrolytes,resulting in a continuous loss of electrochemically active lithium and a relatively low Coulombic efficiency[2].To address these challenges,solid inorganic and polymer electrolytes have emerged as a potentially saferalternative. 展开更多
关键词 LITHIUM polymer PROMPT
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Recycled graphite for more sustainable lithium-ion batteries
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作者 Mayokun Olutogun Anna Vanderbruggen +5 位作者 Christoph Frey Martin Rudolph Dominic Bresser Stefano Passerini Helmholtz Institute Ulm(HIU) Ulm 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期15-24,共10页
The demand for lithium-ion batteries(LIBs)is driven largely by their use in electric vehicles,which is projected to increase dramatically in the future.This great success,however,urgently calls for the efficient recyc... The demand for lithium-ion batteries(LIBs)is driven largely by their use in electric vehicles,which is projected to increase dramatically in the future.This great success,however,urgently calls for the efficient recycling of LIBs at the end of their life.Herein,we describe a froth flotation-based process to recycle graphite—the predominant active material for the negative electrode—from spent LIBs and investigate its reuse in newly assembled LIBs.It has been found that the structure and morphology of the recycled graphite are essentially unchanged compared to pristine commercial anode-grade graphite,and despite some minor impurities from the recycling process,the recycled graphite provides a remarkable reversible specific capacity of more than 350 mAh g^(−1).Even more importantly,newly assembled graphite‖NMC532 cells show excellent cycling stability with a capacity retention of 80%after 1000 cycles,that is,comparable to the performance of reference full cells comprising pristine commercial graphite. 展开更多
关键词 ANODE GRAPHITE lithium-ion battery RECYCLING SUSTAINABILITY
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Fiber Bundle Topology Optimization for Surface Flows
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作者 Yongbo Deng Weihong Zhang +2 位作者 Jihong Zhu Yingjie Xu Jan G Korvink 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期236-264,共29页
This paper presents a topology optimization approach for the surface flows on variable design domains.Via this approach,the matching between the pattern of a surface flow and the 2-manifold used to define the pattern ... This paper presents a topology optimization approach for the surface flows on variable design domains.Via this approach,the matching between the pattern of a surface flow and the 2-manifold used to define the pattern can be optimized,where the 2-manifold is implicitly defined on another fixed 2-manifold named as the base manifold.The fiber bundle topology optimization approach is developed based on the description of the topological structure of the surface flow by using the differential geometry concept of the fiber bundle.The material distribution method is used to achieve the evolution of the pattern of the surface flow.The evolution of the implicit 2-manifold is realized via a homeomorphous map.The design variable of the pattern of the surface flow and that of the implicit 2-manifold are regularized by two sequentially implemented surface-PDE filters.The two surface-PDE filters are coupled,because they are defined on the implicit 2-manifold and base manifold,respectively.The surface Navier-Stokes equations,defined on the implicit 2-manifold,are used to describe the surface flow.The fiber bundle topology optimization problem is analyzed using the continuous adjoint method implemented on the first-order Sobolev space.Several numerical examples have been provided to demonstrate this approach,where the combination of the viscous dissipation and pressure drop is used as the design objective. 展开更多
关键词 Fiber bundle Topology optimization 2-MANIFOLD Surface flow Material distribution method Porous medium model
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