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Pulsed dynamic electrolysis enhanced PEMWE hydrogen production:Revealing the effects of pulsed electric fields on protons mass transport and hydrogen bubble escape

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Journal of Energy Chemistry 2025年第1期 201-214页

作者： Xuewei Zhang wei Zhou Yuming Huang Liang Xie Tonghui Li Huimin kang Lijie Wang Yang Yu Yani Ding Junfeng Li Jiaxiang Chen Miaoting Sun Shuo Cheng Xiaoxiao Meng Jihui Gao Guangbo zhao School of Energy Science and Engineering Harbin Institute of Technology China Datang Technology Innovation Co. Ltd

The transition of hydrogen sourcing from carbon-intensive to water-based methodologies is underway,with renewable energy-powered proton exchange membrane water electrolysis （PEMWE） emerging as the preeminent pathway for hydrogen *** remarkable advancements in this field,confronting the sluggish electrochemical kinetics and inherent high-energy consumption arising from deteriorated mass transport within PEMWE systems remains a formidable *** impediment stems primarily from the hindered protons mass transfer and the untimely hydrogen bubbles *** address these challenges,we harness the inherent variability of electrical energy and introduce an innovative pulsed dynamic water electrolysis *** to constant voltage electrolysis (hydrogen production rate:51.6 m L h-1,energy consumption:5.37 kWh Nm-3H2),this strategy (hydrogen production rate:66 m L h-1,energy consumption:3.83 kWh Nm-3H2) increases the hydrogen production rate by approximately 27%and reduces the energy consumption by about 28%.Furthermore,we demonstrate the practicality of this system by integrating it with an off-grid photovoltaic （PV） system designed for outdoor operation,successfully driving a hydrogen production current of up to 500 mA under an average voltage of approximately 2 *** combined results of in-situ characterization and finite element analysis reveal the performance enhancement mechanism:pulsed dynamic electrolysis （PDE） dramatically accelerates the enrichment of protons at the electrode/solution interface and facilitates the release of bubbles on the electrode *** such,PDE-enhanced PEMWE represents a synergistic advancement,concurrently enhancing both the hydrogen generation reaction and associated transport *** promising technology not only redefines the landscape of electrolysis-based hydrogen production but also holds immense potential for broadening its application across a diverse spectrum of electrocatalytic endeavors.

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Electrochemical disproportionation strategy to in-situ fill cation vacancies with Ru single atoms

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Nano Research 2022年第6期15卷 4980-4985页

作者： kang Xiao Run-Tong Lin Jin-Xin wei Nan Li Hui Li Tianyi Ma zhao-Qing Liu School of Chemistry and Chemical Engineering/Institute of Clean Energy and Materials/Guangzhou Key Laboratory for Clean Energy and Materials Guangzhou UniversityGuangzhou 510006China Centre for Translational Atomaterials Swinburne University of TechnologyHawthornVIC 3122Australia School of Science RMIT UniversityMelbourneVIC 3000Australia

Supported single-atom catalysts(SACs)possess high catalytic activity,selectivity,and atom ***,the atom coordination environments of SACs are difficult to accurately regulate due to the high complexity of coordination site and local environment of ***,we develop an in-situ electrochemical cation-exchange method to fill the cation vacancies in MnO_(2)with Ru single atoms(SAs).This obtained catalyst exhibits high mass activity,which is~44 times higher than commercial RuO2 catalyst and excellent stability,superior to the most state-of-the-art oxygen evolution reaction(OER)*** experimental and theoretical results confirm that the doped Ru can induce charge density redistribution,resulting in the optimized binding of oxygen species,and the strong covalent interaction between Ru and MnO2 for resisting oxidation and *** work will provide a new concept in the synthesis of well-defined local environments of supported SAs.

关键词： single-atom catalysts MnO_(2) Ru disproportionation oxygen evolution reaction

Passivation Behavior of 2507 Super Duplex Stainless Steel in Hot Concentrated Seawater:Influence of Temperature and Seawater Concentration

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Acta Metallurgica Sinica(English Letters) 2022年第2期35卷 326-340页

作者： kang zhao Xiao-Qi Li Li-wei Wang Qi-Rong Yang Lian-Jun Cheng Zhong-Yu Cui College of Mechanical and Electrical Engineering Qingdao UniversityQingdao 266071China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China

The electrochemical behavior and passivation properties of 2507 super duplex stainless steel(SDSS)in the hot concentrated seawater with different concentrations at different temperatures are characterized by electrochemical methods and X-ray photoelectron *** passive film formed on 2507 SDSS belongs to n-type semiconductor and mainly composed of hydroxides and oxides of Fe and Cr under all *** protectiveness of the passive film decreases with the increase in temperature mainly because of the increase in defect density in the passive *** corrosion resistance of 2507 decreases with the increase in seawater concentration,and the critical pitting temperature also decreases.

关键词： Stainless steel Hot concentrated seawater Passive film Pitting

振动疗法联合悬吊训练前交叉韧带重建后患者运动及膝关节功能的变化

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中国组织工程研究 2025年第11期29卷 2225-2230页

作者：陈文汉门杰杨伟赵小宇山西医科大学汾阳学院山西省吕梁市032200

背景:物理疗法对前交叉韧带重建术后恢复至关重要。近年来,许多医师都在优化前交叉韧带重建术后的物理康复方案,但仍然缺乏高效的前交叉韧带重建术后康复训练疗法。目的:探讨振动疗法联合悬吊训练对前交叉韧带重建患者术后运动及膝关节... 详细信息

背景:物理疗法对前交叉韧带重建术后恢复至关重要。近年来,许多医师都在优化前交叉韧带重建术后的物理康复方案,但仍然缺乏高效的前交叉韧带重建术后康复训练疗法。目的:探讨振动疗法联合悬吊训练对前交叉韧带重建患者术后运动及膝关节功能的影响。方法:纳入在上海体育大学附属体育医院就诊的80例首次行单侧前交叉韧带重建患者,按照随机数字表法将患者随机分为振动疗法组和振动疗法+悬吊训练组,每组40例。振动疗法组患者在前交叉韧带重建术后第13周开始进行振动疗法训练(每次10 min,1次/d,每周6次),振动疗法+悬吊训练组患者在前交叉韧带重建术后第13周开始进行振动疗法(每次10 min,1次/d,每周6次)联合悬吊训练(每周2次),共训练8周。训练前及训练8后,采用膝关节Lysholm评分评价膝关节功能,采用等速肌力评估训练系统评估屈膝对称性指数,采用平衡测试系统评估双侧多轴平均轨迹误差差值。结果与结论:(1)与训练前比较,两组患者训练8周后的膝关节Lysholm评分、屈膝与伸膝对称性指数均升高(P<0.05),双侧多轴平均轨迹误差差值降低(P<0.05);与振动疗法组比较,振动疗法+悬吊训练组患者膝关节Lysholm评分、屈膝与伸膝对称性指数均升高(P<0.05),双侧多轴平均轨迹误差差值降低(P<0.05);(2)结果表明,与单独进行振动疗法相比,振动疗法联合悬吊训练可显著改善前交叉韧带重建患者的膝关节功能,增加肌肉力量和对称性,提高平衡稳定性。

关键词：前交叉韧带重建振动疗法悬吊训练膝关节功能肌肉力量对称性平衡稳定性

Regulating ion transport behaviors toward dendrite-free potassium metal batteries:recent advances and perspectives

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Rare Metals 2024年第4期43卷 1435-1460页

作者： Lu-kang zhao Xuan-Wen Gao Tian-Zhen Ren Da Wang Da-wei Wang zhao-Meng Liu Hong Chen Wen-Bin Luo School of Metallurgy Northeastern UniversityShenyang110819China School of Chemical Engineering The University of New South WalesSydneyNSW2052Australia

With abundant potassium resources and high capacity,potassium metal batteries(PMBs)present a compelling option for the next generation of energy storage ***,PMBs suffer from an unstable anode interface caused by uncontrolled dendrite growth,which results in unsatisfactory cyclability and safety *** investigations suggest that significant progress has been made in enhancing the interfacial stability of *** various effective strategies for stabilizing interfaces can ultimately be attributed to the regulation of the sluggish ion transfer kinetics and irregular deposition,i.e.,the arrangement of ion transport behaviors at the *** modulation of ions transport rate and ions deposition directions makes it possible to obtain a dendrite-free and smooth deposition ***,the influencing factors and action mechanism of K^(+)interface transport behaviors are discussed to understand the nature of material design for constructing stable anode interfaces,including regulating the solvation and desolvation structures,accelerating K^(+)transport kinetics and controlling K^(+)deposition *** addition,the deficiencies and prospects of the research on electrolyte,separators and designed electrode involved in the manufacturing and testing and ion transport process of PMBs are *** review is expected to provide some possible directions for constructing dendrite-free interfaces in advanced PMBs-related research and offer significant insights for prospective experimental research and commercial applications.

关键词： Ion transport rate Ion transport direction Interface Potassium metal batteries Dendrites growth

Gradient sparsification for efficient wireless federated learning with differential privacy

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Science China(Information Sciences) 2024年第4期67卷 272-288页

作者： kang wei Jun LI Chuan MA Ming DING Feng SHU Haitao zhao Wen CHEN Hongbo ZHU School of Electronic and Optical Engineering Nanjing University of Science and Technology Zhejiang Lab Key Laboratory of Computer Network and Information Integration(Southeast University) Ministry of Education Data61 Commonwealth Scientific and Industrial Research Organisation School of Information and Communication Engineering Hainan University School of Communications and Information Engineering Nanjing University of Posts and Telecommunications School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

Federated learning(FL) enables distributed clients to collaboratively train a machine learning model without sharing raw data with each other. However, it suffers from the leakage of private information from uploading models. In addition, as the model size grows, the training latency increases due to the limited transmission bandwidth and model performance degradation while using differential privacy(DP)protection. In this paper, we propose a gradient sparsification empowered FL framework with DP over wireless channels, to improve training efficiency without sacrificing convergence performance. Specifically, we first design a random sparsification algorithm to retain a fraction of the gradient elements in each client’s local model, thereby mitigating the performance degradation induced by DP and reducing the number of transmission parameters over wireless channels. Then, we analyze the convergence bound of the proposed algorithm, by modeling a non-convex FL problem. Next, we formulate a time-sequential stochastic optimization problem for minimizing the developed convergence bound, under the constraints of transmit power, the average transmitting delay, as well as the client’s DP requirement. Utilizing the Lyapunov drift-plus-penalty framework, we develop an analytical solution to the optimization problem. Extensive experiments have been implemented on three real-life datasets to demonstrate the effectiveness of our proposed algorithm. We show that our proposed algorithms can fully exploit the interworking between communication and computation to outperform the baselines, i.e., random scheduling, round robin, and delay-minimization algorithms.

关键词： federated learning differential privacy gradient sparsification Lyapunov drift convergence analysis

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第01期 337-349页

作者： Meiyun Xu Song Gu Fulong Chen Zhe zhao Peng Liu Daoben Hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

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Wave effect of gravitational waves intersected with a microlens field Ⅱ:An adaptive hierarchical tree algorithm and population study

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 241-254页

作者： Xikai Shan Guoliang Li Xuechun Chen Wen zhao Bin Hu Shude Mao Department of Astronomy Tsinghua University Purple Mountain Observatory Chinese Academy of Sciences Institute for Frontier in Astronomy and Astrophysics Beijing Normal University School of Physics and Astronomy Beijing Normal University School of Astronomy and Space Science University of Science and Technology of China CAS Key Laboratory for Researches in Galaxies and Cosmology Department of Astronomy University of Science and Technology of ChinaChinese Academy of Sciences

The gravitational lensing wave effect generated by a microlensing field embedded in a lens galaxy is an inevitable phenomenon in strong lensed gravitational waves （SLGWs）.This effect presents both challenges and opportunities for the detection and application of ***,investigating this wave effect requires computing a complete diffraction integral over each microlens in the *** is extremely time-consuming due to the large number of microlenses （10～3-10～6）.Therefore,simply adding all the microlenses is ***,the complexity of the time delay surface makes the lens plane resolution a crucial factor in controlling numerical *** this paper,we propose a trapezoid approximation-based adaptive hierarchical tree algorithm to meet the challenges of calculation speed and *** find that this algorithm accelerates the calculation by four orders of magnitude compared to the simple adding method and is one order of magnitude faster than the fixed hierarchical tree algorithm proposed for electromagnetic *** importantly,our algorithm ensures controllable numerical errors,increasing confidence in the *** with our previous work （***.66,239511,2023）,this paper addresses all numerical issues,including integral convergence,precision,and computational time1).Finally,we conducted a population study on the microlensing wave effect of SLGWs using this algorithm and found that the microlensing wave effect cannot be ignored,especially for Type II SLGWs （from saddle position of the time delay surface） due to their intrinsic geometric structures and their typical intersection with a denser microlensing ***,more than 33%（11%） of SLGWs have a mismatch larger than 1%（3%） compared to the unlensed ***,we found that the mismatch between signal pairs in a doubly imaged GW is generally larger than 10-3,and 61%（25%） of signal pairs have a mismatch larger than 1%（3%）.Therefo

关键词： gravitational lensing diffractional integral algorithm gravitational wave

Self-Tuning Asynchronous Filter for Linear Gaussian System and Applications

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IEEE/CAA Journal of Automatica Sinica 2018年第6期5卷 1054-1061页

作者： Wenjun Lv Yu kang Yunbo zhao Department of Automation University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Fire Science Department of Automation and Institute of Advanced TechnologyUniversity of Science and Technology of ChinaHefei 230027China Key Laboratory of Technology in GeoSpatial Information Processing and Application System Chinese Academy of SciencesBeijing 100190China College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

In this paper, optimal filtering problem for a class of linear Gaussian systems is studied. The system states are updated at a fast uniform sampling rate and the measurements are sampled at a slow uniform sampling rate. The updating rate of system states is several times the sampling rate of measurements and the multiple is constant. To solve the problem,we will propose a self-tuning asynchronous filter whose contributions are twofold. First, the optimal filter at the sampling times when the measurements are available is derived in the linear minimum variance sense. Furthermore, considering the variation of noise statistics, a regulator is introduced to adjust the filtering coefficients adaptively. The case studies of wheeled robot navigation system and air quality evaluation system will show the effectiveness and practicability in engineering.

关键词： Air quality evaluation system linear Gaussian system wheeled robot navigation system