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Progresses on two-phase modeling of proton exchange membrane water electrolyzer

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Energy Reviews 2024年第3期3卷 30-57页

作者： Boshi Xu Tao Ouyang Yang Wang Yang Yang Jun Li Liangliang Jiang Chaozhong qin Dingding ye Rong Chen Xun Zhu Qiang Liao Key Laboratory of Low-grade Energy Utilization Technologies and Systems Ministry of EducationChongqing UniversityChongqing400030China Institute of Engineering Thermophysics School of Energy and Powering EngineeringChongqing UniversityChongqing400030China Department of Chemical and Petroleum Engineering The University of CalgaryCalgaryAlbertaCanada State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing400044China

The Proton Exchange Membrane(PEM)water electrolyzer is considered one of the promising energy storing means for harnessing variable renewable energy sources to produce *** the internal fluid dynamics,which are often challenging to directly observe experimentally,has prompted the use of numerical models to investigate two-phase flow within PEM water *** this study,we provide a comprehensive review of prior research focusing on two-phase modeling of PEM electrolyzers,encompassing both components at mesoscopic scales and the full electrolyzer at the macroscopic *** delve into the specifics of various modeling approaches for two-phase flow at different scales and summarize and discuss the current state of the art in the ***,two-phase models for the full electrolyzer predominantly employ a macroscopic homogeneous ***,mesoscopic and microscopic models capable of tracking phase interfaces are limited to *** persist in integrating various modeling scales into a comprehensive electrolyzer model,particularly in coupling two-phase flow between the channels and porous *** efforts should focus on developing multi-scale models and simulating two-phase flow under fluctuating input ***,given the structural similarities between PEM water electrolyzers and PEM fuel cells,we compare and discuss differences in two-phase modeling between the two *** work offers the insights for researchers in the field of modeling of PEM water electrolyzers and even fuel cells.

关键词： Proton exchange membrane(PEM)water electrolyzer Two-phase model Multiscale modeling Water management Numerical simulation

Developing a novel quantitative parameter for characterizing spatial distribution of fish following exposure to chemicals and wastewater:Behavioral Gini coefficient

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Journal of Environmental Sciences 2024年第7期141卷 129-138页

作者： Xuanyue Chen Yuanyuan Li Zhanfen qin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

While the spatial distribution pattern of fish is increasingly used for toxicological test o chemicals or wastewater,no ideal parameter is available for quantitative assessment of spa tial distribution,especially uneven distribution with multiple ***,to develop a quantitative assessment parameter for spatial distribution,the zebrafish were exposed to ethanol,pentylenetetrazole(PTZ),paraquat dichloride(paraquat)and wastewater,followed by a behavioral test in a narrow *** data was acquired and analyzed by id Tracker and *** comparing the effects of all treatments on behavior parameters we confirmed that the spatial distribution was more easily altered rather than general loco motor parameters,e.g.0.7-70 mg/L PTZ and 5-20 mg/L paraquat being effective for altering spatial distribution but having little effects on general locomotor *** on the heatmap,i.e.,the cumulative proportion of grids and that of frequency in grids,we calcu lated the behavioral Gini coefficient(G_(b))for quantitative assessment of fish spatial distri *** Gini coefficient ranged from zero to 1,with larger values meaning poorer even ness of spatial *** note,G_(b)showed smaller coefficient of variations(CV)with3%-19%between replicate tanks in all treatments than the highest frequency(4%-79%),dis playing well ***,G_(b)addressed the challenge of the complicated heatmap with multiple ***,the behavioral Gini coefficient we established is an idea parameter to quantitatively assess spatial distribution of fish shoal,which is expected to be applied in toxicity testing for chemicals and wastewater and automatic quality monitoring for surface water and aquaculture water.

关键词： Zebrafish Behavioral test Spatial distribution Behavioral Gini coefficient

Tuning electronic properties of cobalt phthalocyanines for oxygen reduction and evolution reactions

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Science China Chemistry 2024年第1期67卷 398-407页

作者： Jianlin Jiang Zhen Liu Shuaijun Pan Xinnian xia Bing qin Yang Hu Xuxu Wang Jiamin Lan Yu Gu Encai Ou Weijian Xu Joseph J.Richardson Rui Guo SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410082China College of Chemistry and Materials Science Hunan Agricultural UniversityChangsha 410128China Department of Chemical Engineering The University of MelbourneParkville 3010Australia College of Environmental Science and Engineering Hunan UniversityChangsha 410082China School of Engineering RMIT UniversityMelbourneVictoria 3001Australia

Metal–phthalocyanines are a class of catalytically active materials promising in energy conversion and storage fields(e.g.,electrocatalysis).However,understanding and controlling the electrochemical properties in metal-phthalocyanine systems is ***,we elucidate the electrocatalytic origins of a series of cobalt-phthalocyanine molecular catalysts and finetune their electronic properties at the atomic level,both experimentally and *** interactions between the cobalt center and the local coordination environment are regulated by introducing either electron-donating or electron-withdrawing groups on the phthalocyanine ligand,and the spin-orbit splitting of cobalt is increased by~0.15 eV compared with the nonsubstituted ***,the aminated cobalt phthalocyanine-based electrocatalysts exhibit low free energies in the ratedetermining steps of the oxygen reduction(-1.68 eV)and oxygen evolution reactions(0.37 eV).This contributes to the high electrocatalytic activity(e.g.,a halfwave potential of 0.84 V and an overpotential of 0.30 V at 10 mAcm^(-2)),featuring a high selectivity of a four-electron pathway(i.e.,a negligible by-product of hydrogen peroxide).These catalysts also exhibit exceptional kinetic current density(Tafel slope of 100 mV dec^(-1))in oxygen reduction reactions,in addition to a superior power density(158 mWcm^(-2))and a high cycling stability(>1,300 cycles)in Zn-air batteries,outperforming the commercial Pt/C and/or RuO2counterparts.

关键词： interfacial wettability molecular catalysts carbon nanotubes density functional theory electrochemistry

J-shaped association between dietary thiamine intake and the risk of cognitive decline in cognitively healthy,older Chinese individuals

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General Psychiatry 2024年第1期37卷 44-52页

作者： Chengzhang Liu Qiguo Meng Yuanxiu Wei Xinyue Su Yuanyuan Zhang Panpan He Chun Zhou Mengyi Liu Ziliang ye xianhui qin Department of Epidemiology and Biostatistics School of Public HealthAnhui Medical UniversityHefeiAnhuiChina institute of Biomedicine Anhui Medical UniversityHefeiAnhuiChina Division of Nephrology Nanfang HospitalSouthern Medical UniversityNational Clinical Research Center for Kidney DiseaseState Key Laboratory of Organ Failure ResearchGuangdong Provincial Institute of NephrologyGuangdong Provincial Key Laboratory of Renal Failure ResearchGuangzhou Regenerative Medicine and Health Guangdong LaboratoryGuangzhouGuangdongChina

Background The prospective association of dietary thiamine intake with the risk of cognitive decline among the general older adults remains *** To investigate the association between dietary thiamine intake and cognitive decline in cognitively healthy,older Chinese *** The study included a total of 3106 participants capable of completing repeated cognitive function *** nutrient intake information was collected through 3-day dietary recalls and using a 3-day food-weighed method to assess cooking oil and condiment *** decline was defined as the 5-year decline rate in global or composite cognitive scores based on a subset of items from the Telephone Interview for Cognitive *** The median follow-up duration was 5.9 *** was a J-shaped relationship between dietary thiamine intake and the 5-year decline rate in global and composite cognitive scores,with an inflection point of 0.68 mg/day(95%confidence interval(Cl):0.56 to 0.80)and a minimal risk at 0.60-1.00 mg/day of dietary thiamine *** the inflection point,thiamine intake was not significantly associated with cognitive *** the inflection point,each unit increase in thiamine intake(mg/day)was associated with a significant decrease of 4.24(95%Cl:2.22 to 6.27)points in the global score and 0.49(95%Cl:0.23 to 0.76)standard units in the composite score within 5 years.A stronger positive association between thiamine intake and cognitive decline was observed in those with hypertension,obesity and those who were non-smokers(all p<0.05).Conclusions This study revealed a J-shaped association between dietary thiamine intake and cognitive decline in cognitively healthy,older Chinese individuals,with an inflection point at 0.68 mg/day and a minimal risk at 0.60-1.00 mg/day of dietary thiamine intake.

关键词： intake shaped cognitive

Non-dimensional analysis on blast wave propagation in foam concrete:Minimum thickness to avoid stress enhancement

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Defence Technology（防务技术） 2024年第6期36卷 30-46页

作者： Ya Yang xiangzhen Kong qin Fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007JiangsuChina

Foam concrete is a prospective material in defense engineering to protect structures due to its high energy absorption capability resulted from the long plateau ***,stress enhancement rather than stress mitigation may happen when foam concrete is used as sacrificial claddings placed in the path of an incoming blast *** investigate this interesting phenomenon,a one-dimensional difference model for blast wave propagation in foam concrete is firstly proposed and numerically solved by improving the second-order Godunov *** difference model and numerical algorithm are validated against experimental results including both the stress mitigation and the stress *** difference model is then used to numerically analyze the blast wave propagation and deformation of material in which the effects of blast loads,stress-strain relation and length of foam concrete are *** particular,the concept of minimum thickness of foam concrete to avoid stress enhancement is ***,non-dimensional analysis on the minimum thickness is conducted and an empirical formula is proposed by curve-fitting the numerical data,which can provide a reference for the application of foam concrete in defense engineering.

关键词： Foam concrete Blast wave propagation Non-dimensional analysis Stress enhancement

Gas diffusion in catalyst layer of flow cell for CO_(2) electroreduction toward C_(2+) products

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Nano Research 2024年第3期17卷 1101-1106页

作者： Xiqing Wang qin Chen Yajiao Zhou Yao Tan ye Wang Hongmei Li Yu Chen Mahmoud Sayed Ramadan A.Geioushy Nageh K.Allam Junwei Fu Yifei Sun Min Liu Hunan Joint International Research Center for Carbon Dioxide Resource Utilization School of Physics and ElectronicsCentral South UniversityChangsha 410083China School of Energy and Power Engineering Beihang UniversityBeijing 100191China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China Central Metallurgical Research and Development Institute(CMRDI) P.O.Box 87Helwan 11421CairoEgypt Energy Materials Laboratory School of Sciences and EngineeringThe American University in CairoNew Cairo 11835Egypt Research Center for Advanced Energy and Carbon Neutrality Beihang UniversityBeijing 100191China

The use of gas diffusion electrode(GDE)based flow cell can realize industrial-scale CO_(2) reduction reactions(CO_(2)RRs).Controlling local CO_(2) and CO intermediate diffusion plays a key role in CO_(2)RR toward multi-carbon(C_(2+))*** this work,local CO_(2) and CO intermediate diffusion through the catalyst layer(CL)was investigated for improving CO_(2)RR toward C_(2+)*** gas permeability tests and finite element simulation results indicated CL can balance the CO_(2) gas diffusion and residence time of the CO intermediate,leading to a sufficient CO concentration with a suitable CO_(2)/H_(2)O supply for high C_(2+)*** a result,an excellent selectivity of C_(2+)products~79%at a high current density of 400 mA·cm^(-2) could be obtained on the optimal 500 nm Cu CL(Cu500).This work provides a new insight into the optimization of CO_(2)/H_(2)O supply and local CO concentration by controlling CL for C_(2+)products in CO_(2)RR flow cell.

关键词： gas diffusion electrode CO_(2)reduction Cu mass transfer C_(2)product

Test of the Brans-Dicke theory with GW200105 and GW200115

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Communications in Theoretical Physics 2024年第7期76卷 83-93页

作者： qin Fei Yingjie Yang Department of Mathematics and Physics School of Biomedical EngineeringSouthern Medical UniversityGuangzhou 510515China School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003China

We study whether it is possible to constrain the Brans-Dicke(BD)theory from the measurement of gravitational waves(GW)released in neutron star-black hole *** the scalar field modifications through monopole and dipole radiations,we find additional contributions to the phase evolution in the emitted gravitational *** effectively calculating such effect in the post-Newtonian order,we are in a position to measure the scalar field and give bounds on the BD coupling parameterω_(BD).We derive the analytical expression for the phase modification due to the orbital eccentricity of eccentric binaries in both general relativity and BD *** the Bayesian analysis,we obtain the constraints on ω_(BD) from the GW events,GW200105 and GW200115.

关键词： cosmology Brans-Dicke theory gravitational wave

Efficient Unsupervised Image Stitching Using Attention Mechanism with Deep Homography Estimation

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Computers, Materials & Continua 2024年第4期79卷 1319-1334页

作者： Chunbin qin xiaotian Ran School of Artificial Intelligence Henan UniversityZhengzhou450000China

Traditional feature-based image stitching techniques often encounter obstacles when dealing with images lackingunique attributes or suffering from quality degradation. The scarcity of annotated datasets in real-life scenesseverely undermines the reliability of supervised learning methods in image stitching. Furthermore, existing deeplearning architectures designed for image stitching are often too bulky to be deployed on mobile and peripheralcomputing devices. To address these challenges, this study proposes a novel unsupervised image stitching methodbased on the YOLOv8 (You Only Look Once version 8) framework that introduces deep homography networksand attentionmechanisms. Themethodology is partitioned into three distinct stages. The initial stage combines theattention mechanism with a pooling pyramid model to enhance the detection and recognition of compact objectsin images, the task of the deep homography networks module is to estimate the global homography of the inputimages consideringmultiple viewpoints. The second stage involves preliminary stitching of the masks generated inthe initial stage and further enhancement through weighted computation to eliminate common stitching *** final stage is characterized by adaptive reconstruction and careful refinement of the initial stitching *** experiments acrossmultiple datasets are executed tometiculously assess the proposed model. Ourmethod’s Peak Signal-to-Noise Ratio (PSNR) and Structure Similarity Index Measure (SSIM) improved by 10.6%and 6%. These experimental results confirm the efficacy and utility of the presented model in this paper.

关键词： Unsupervised image stitching deep homography estimation YOLOv8 attention mechanism

论审核批准对宅基地强制收回制度的体系构造——兼论《土地管理法》第66条第1款的适用

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华中农业大学学报（社会科学版） 2024年第2期 197-206页

作者：夏沁中南大学法学院湖南长沙410082

宅基地强制收回直接关乎着宅基地有偿退出的范围,是新一轮深化宅基地改革的关键性内容。而受制于收回效力认定的不完备性,还应当以对此具有实质影响的审核批准作为类型化的区分标准。其中,作为构成性事实的审核批准,与宅基地收回关系的... 详细信息

宅基地强制收回直接关乎着宅基地有偿退出的范围,是新一轮深化宅基地改革的关键性内容。而受制于收回效力认定的不完备性,还应当以对此具有实质影响的审核批准作为类型化的区分标准。其中,作为构成性事实的审核批准,与宅基地收回关系的形成和变更直接相关,能够产生消灭宅基地使用权的法律效力;作为确认性事实的审核批准,则仅确认宅基地使用权是否已经消灭,而不决定或直接影响宅基地使用权的变动。基于此,两类不同的审核批准构成了宅基地强制收回制度的基本类型,从而实现了该制度的体系化构造。

关键词：宅基地使用权宅基地强制收回审核批准体系构造