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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100卷 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.

关键词： Electrolysis

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足月妊娠可疑羊水过少孕妇阴道试产的探讨

中国基层医药 2010年第9期17卷 1179-1180页

作者：俞艇蔚刘增佑王森深圳市第六人民医院产科广东省深圳518052

目的分析足月妊娠妇女超声检查提示可疑羊水过少时，阴道试产对围生期结局的影响。方法应用羊水指数（AFI）估测羊水量，并测定脐动脉收缩期最大血流速度（S）和舒张末期血流速度（D）比值（S／D），测定血雌三醇（E3），结合胎无应激... 详细信息

目的分析足月妊娠妇女超声检查提示可疑羊水过少时，阴道试产对围生期结局的影响。方法应用羊水指数（AFI）估测羊水量，并测定脐动脉收缩期最大血流速度（S）和舒张末期血流速度（D）比值（S／D），测定血雌三醇（E3），结合胎无应激试验（NST）和缩宫素激惹试验（OCT）或宫缩应激试验（CST）进行综合评价无异常，分析比较320例超声诊断可疑羊水过少的足月妊娠妇女（观察组）和320例羊水量正常无高危因素的足月妊娠妇女（对照组）阴道试产的分娩结局。结果两组新生儿窒息的发生率（9．1％与11．8％）和新生儿死亡率差异无统计学意义（P〉0．05），观察组急诊剖宫产率（30．0％）升高（P〈0．05）。结论超声诊断可疑羊水过少的足月妊娠妇女，在严密监护下可行阴道试产。

关键词：妊娠羊水过少分娩超声检查产前

Si-C Foam Porous-Medium Combustion Power-Generation System for Low-Calorific-Value Biomass Syngas

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Journal of Thermal Science 2025年第1期34卷 206-222页

作者： YANG Jianwen CHEN wei CAO Bingwei LIU Xinhui LI Hang College of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-C foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

关键词： biomass combined heat and power (CHP) gasification porous media combustion power generation

Melting Evaluation of Phase Change Materials Impregnated into Cascaded Metal Foams with Regionalized Enhancement

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Journal of Thermal Science 2025年第1期34卷 223-241页

作者： wei Xinyi ZHANG Nan ZHANG Zhaoli CAO Xiaoling yuAN Yanping School of Mechanical Engineering Southwest Jiaotong University

Metal foam promotes the heat transfer of phase change materials(PCMs) in the penalty of reducing the energy storage density of the composite *** this work,the effects of constant porosity(0.96,0.94,0.92,or 0.90) and pore density(PPI) of metal foam on heat transfer of composite PCMs are *** rate could be enhanced by employing with low porosity copper ***,aiming to the right bottom phase changing "dead region",a regionalized enhancement strategy of cascaded metal foams is *** dynamic melting performances of all the composite PCMs are comprehensively *** results reveal that the cascaded configuration is beneficial for *** show that the horizontal strategy enhances melting performance:a maximum of 17.98% reduction in total melting time could be reached when the rear part porosity is 90%.The energy storage density rate could be raised by 5.48%.Besides,the vertical strategy performs with a better average temperature uniformity of 0.441 and brings a lower temperature in the heated *** sum up,the regionalized enhancement of copper foam provides better performance in the phase change *** shows significant potential for solar heat storage and thermal protection.

关键词： copper metal foam heat transfer enhancement phase change materials regionalized enhancement

A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期34卷 145-158页

作者： GUO Xingduo LI Yinran LI Rennian MA yulong wei Kui College of Energy and Power Engineering Lanzhou University of Technology Key Laboratory of Fluid Machinery and Systems Gansu Provincial Technology Centre for Wind Turbines

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL) wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

关键词： horizontal axis wind turbine turbulence wind tunnel experiment wind turbine wake

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浅谈吉林省镇赉县城区浅层地温能的开发利用

吉林地质 2016年第3期35卷 120-122页

作者：傅玉李忠野于海婷李伟孙宁吉林省水文地质调查所吉林长春130012

浅层地温能是可再生的新型环保能源。镇赉县城区内浅层地温能赋存的空间有较大的热容量,且有较强的恢复能力。但对城区浅层地温能的开发利用应具有科学的总体规划,防止盲目的开发破坏地质环境。通过对城区内浅层地温能开发利用条件的逐... 详细信息

浅层地温能是可再生的新型环保能源。镇赉县城区内浅层地温能赋存的空间有较大的热容量,且有较强的恢复能力。但对城区浅层地温能的开发利用应具有科学的总体规划,防止盲目的开发破坏地质环境。通过对城区内浅层地温能开发利用条件的逐步分析,提出适宜地下水水源热泵开发利用浅层地温能的方案及注意事项。

关键词：浅层地温能开发利用条件开发利用方案注意事项镇赉县城区

Effect of a Carbon Fibre-steel Fibre-graphite Conductive Filler on the Electrothermal Properties of Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 141-151页

作者： FAN Yanan wei Hong ZHENG Hongyong DU Hongxiu Department of Architecture and Environmental Engineering Taiyuan UniversityTaiyuan 030032China College of Civil Engineering Taiyuan University of TechnologyTaiyuan 030032China

Carbon fibre,steel fibre and graphite were used as conductive fillers to prepare cementitious materials with excellent electrothermal *** electrically conductive cementitious materials with different volume dosages were analysed through compressive and flexural strength,electrochemical impedance spectroscopy and temperature rise *** equivalent circuit model was established to study the electrically conductive heat generation mechanism in the electrically conductive cementitious *** results indicate that the mechanical properties of cementitious composite materials with a ternary conductive phase are better than those of pristine cementitious materials because the fibrous filler improves their mechanical ***,the incorporation of graphite in the material reduces its *** fibrous and point-like conductive phase materials into the cementitious material enhances the overall conductive pathway and considerably reduces the electrical resistance of the cementitious material,enhancing its conductive *** volume ratios of carbon fibre,steel fibre and graphite that achieve an optimal complex doping in the cementitious material were 0.35%,0.6%and 6%,*** was determined using the mutation point of each circuit element parameter as the percolation *** addition,at a certain safety voltage,there is a uniform change between the internal and surface temperatures of the conductive cementitious material,and the heating effect in this materialis is considerably better than that in the pristine cementitious material.

关键词： cementitious composites conductive fillers electrothermal properties electrochemical impedance spectroscopy

微囊化PC12细胞移植治疗帕金森病微胶囊材料的生物学特征(英文)

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中国临床康复 2005年第30期9卷 229-231,i0006页

作者：雄鹰王为于炜婷郭昕王秋艳胡国华宋月平马小军中国科学院大连化学物理研究所生物医用材料工程组辽宁省大连市116023 吉林大学第二医院神经内科吉林省长春市130041

背景:帕金森病系中脑黑质多巴胺能神经元变性,使纹状体内多巴胺减少而出现一系列临床症状。将分泌多巴胺的细胞或转染多巴胺合成限速酶基因的细胞进行脑内移植,能一定程度地逆转或改善症状,但存在免疫排斥的问题。目的:探讨在不使用免... 详细信息

背景:帕金森病系中脑黑质多巴胺能神经元变性,使纹状体内多巴胺减少而出现一系列临床症状。将分泌多巴胺的细胞或转染多巴胺合成限速酶基因的细胞进行脑内移植,能一定程度地逆转或改善症状,但存在免疫排斥的问题。目的:探讨在不使用免疫抑制剂的情况下,应用免疫隔离的方法进行细胞移植治疗帕金森病大鼠,观察微胶囊的生物相容性及其机械强度。设计:随机对照实验。单位:中国科学院大连化学物理研究所生物技术部生物医用材料工程组,吉林大学第二医院神经内科。材料:实验于2003-08/2004-02在吉林大学第二临床学院动物实验中心完成。选择雄性Wistar大鼠40只。PC12细胞由中国科学院上海细胞生物学研究所提供。方法:在纹状体内注射6-羟多巴胺盐溶液制备帕金森病动物模型。其中制备模型成功大鼠25只,随机分为微囊化细胞移植组12只:将25μL的微囊化细胞悬液(相当于2.5×104个细胞)分两点定位注射到动物模型右侧(损毁侧)纹状体内。非微囊化细胞移植组7只:植入25μL裸PC12细胞悬液(相当于5×104个细胞)。空微胶囊移植组6只:植入25μL的空微胶囊悬液。各组大鼠在移植后第7天注射阿朴吗啡(0.05mg/kg),然后记录每只大鼠的旋转行为,1次/周,共12周。术后12周处死大鼠,取脑组织进行病理学观察,回收微胶囊观察生物相容性和免疫隔离作用。主要观察指标:①微胶囊在大鼠纹状体内的生物相容性。②微胶囊的免疫隔离作用。③各组大鼠移植前后平均旋转圈数。结果:进入结果分析25只,其余均为模型制备不成功而脱落。①微胶囊的生物相容性:回收的海藻酸钠-壳聚糖-海藻酸钠微胶囊,形态完整,表面光滑,无炎细胞浸润。②微胶囊的免疫隔离作用:微胶囊内的PC12细胞继续增殖,部分形成了细胞团。③各组大鼠移植前后平均旋转圈数:移植前各组大鼠的单侧旋转记录无明显不同(P>0.05)。微囊化细胞移植组移植2周后平均旋转圈数明显低于移植前,甚至停止旋转,症状的改善保持至移植后12周。非微囊化细胞移植组的平均旋转圈数也明显低于移植前,但8,12周又有上升趋势,与移植前无明显变化(P>0.05)。空微胶囊移植组移植前后的旋转圈数基本一致。结论:①海藻酸钠-壳聚糖-海藻酸钠微胶囊有良好的生物相容性和机械强度,在移植部位不引发炎症反应,并保持形态的完整性。②海藻酸钠-壳聚糖-海藻酸钠微胶囊有免疫保护作用,包封的PC12细胞移植到帕金森病大鼠的脑内可以长期存活,继续保持正常的生理功能,通过合成和释放多巴胺,改善帕金森病大鼠的症状。

关键词：帕金森病微胶囊细胞移植 PC12细胞

海藻酸钠-乙酸乙烯酯均相接枝共聚物合成及性能评价

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化学研究与应用 2013年第8期25卷 1097-1101页

作者：许冠哲刘袖洞王冰于炜婷丁东慧马小军大连大学环境与化学工程学院辽宁大连116622 中国科学院大连化学物理研究所辽宁大连116023 中国科学院大学北京100049

本文采用了均相接枝共聚的方法合成了疏水改性的海藻酸钠-乙酸乙烯酯共聚物(SA-g-PVAc)。使用红外光谱、元素分析、凝胶渗透色谱手段对产物接枝度、溶解性能、分子量进行了评价,并考察了相关性能的变化规律。

关键词：海藻酸钠乙酸乙烯酯均相接枝共聚疏水改性