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Special issue on electrochemical conversion and utilization of hydrogen energy

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Frontiers in Energy 2024年第3期18卷 263-264页

作者： Yun ZHENG Bo YU xiaogang fu Jiujun ZHANG Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China State Key Laboratory of Solidification Processing Atomic Control&Catalysis Engineering LaboratorySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

The concerns over energy crisis and climate change caused by the excessive consumption of fossil fuels and the associated emission of greenhouse gases, have driven many countries to develop policies for an energy transition into zero-carbon energy sources, essentially aiming at decarbonizing their energy systems. Among various renewable sources, hydrogen has been hailed as an ideal alternative to provide secure, cost-effective, and non-polluting energy. In recent years, there has been noteworthy progress in hydrogen electrochemical conversion and utilization techniques and devices, including water electrolyzers, proton-exchange membrane fuel cells (PEMFCs), solid oxide fuel cells (SOFCs), etc. Each of these technologies has yielded a series of encouraging advances. To showcase these recent advances, Frontiers in Energy is launching a special issue titled “electrochemical conversion and utilization of hydrogen energy”.

关键词： hydrogen energy. electrochemical

Strain engineering of Pt-based electrocatalysts for oxygen reaction reduction

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Frontiers in Energy 2024年第2期18卷 241-262页

作者： Zeyu WANG Yanru LIU Shun CHEN Yun ZHENG xiaogang fu Yan ZHANG Wanglei WANG State Key Laboratory of Solidification Processing Atomic Control and Catalysis Engineering LaboratorySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Oral and Maxillofacial Reconstruction and Regeneration National Clinical Research Center for Oral DiseasesShaanxi Key Laboratory of StomatologyDepartment of Dental MaterialsSchool of StomatologyThe Fourth Military Medical UniversityXi’an 710032China Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Key Laboratory of Marine Chemistry Theory and Technology(Ministry of Education) College of Chemistry and Chemical EngineeringOcean University of ChinaQingdao 266100China

Proton exchange membrane fuel cells(PEMFCs)are playing irreplaceable roles in the construction of the future sustainable energy ***,the insufficient performance of platinum(Pt)-based electrocatalysts for oxygen reduction reaction(ORR)hinders the overall efficiency of *** the surface strain of catalysts is considered an effective way to tune their electronic structures and therefore optimize catalytic *** this paper,insights into strain engineering for improving Pt-based catalysts toward ORR are elaborated in ***,recent advances in understanding the strain effects on ORR catalysts are comprehensively ***,strain engineering methodologies for adjusting Ptbased catalysts are comprehensively ***,further information on the various challenges and potential prospects for strain modulation of Pt-based catalysts is provided.

关键词： strain engineering Pt-based catalysts oxygen reduction reaction(ORR) catalytic performance proton exchange membrane fuel cells(PEMFCs)

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两型超声速进气道平飞减速时的稳定性

航空动力学报 2024年第1期39卷 200-206页

作者：符小刚李俊浩杨柳中国飞行试验研究院发动机所西安710089

通过飞行试验,研究了一种二元斜板式及蚌式超声速进气道在马赫数1.5快收发动机油门平飞减速至马赫数为1.05过程中的畸变及稳定性水平。对比表明:减速过程中二元进气道总压畸变、稳定性裕度均随发动机换算转速的下降减小后保持稳定,而蚌... 详细信息

通过飞行试验,研究了一种二元斜板式及蚌式超声速进气道在马赫数1.5快收发动机油门平飞减速至马赫数为1.05过程中的畸变及稳定性水平。对比表明:减速过程中二元进气道总压畸变、稳定性裕度均随发动机换算转速的下降减小后保持稳定,而蚌式进气道畸变先上升再下降后保持稳定,稳定性裕度先下降再略微上升后保持稳定。减速过程前半段,蚌式进气道畸变更大,二元进气道稳定性裕度下降更快;减速过程后半段,两型进气道畸变水平接近,稳定性裕度均较低。分析也表明,仅使用流量系数的相对差值计算的进气道稳定裕度反映的进气道流通能力信息比使用总压恢复系数与流量系数之比的相对差值更全面,推荐采用前者作为进气道稳定性裕度评价指标。

关键词：蚌式进气道进气道喘振进气畸变流量系数稳定性裕度

基于Notch1/Hes1通路分析替莫唑胺对肺癌干细胞增殖、分化的影响

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中国当代医药 2024年第12期31卷 79-82页

作者：何成付小刚江西省新余市人民医院呼吸与危重症医学科江西新余330800

目的基于Notch1/Hes1通路探讨和分析替莫唑胺抑制肺癌干细胞增殖、分化的影响作用及机制。方法选取2020年1月至2022年12月江西省新余市人民医院呼吸与危重症医学科收治的60例肺癌患者开展此次临床实践研究,对患者行肺癌干细胞A549(A549-... 详细信息

目的基于Notch1/Hes1通路探讨和分析替莫唑胺抑制肺癌干细胞增殖、分化的影响作用及机制。方法选取2020年1月至2022年12月江西省新余市人民医院呼吸与危重症医学科收治的60例肺癌患者开展此次临床实践研究,对患者行肺癌干细胞A549(A549-SCs)分离培养,采用流式细胞术鉴定A549-CSCs,检测筛选肺癌干细胞。采用随机数字表法将筛选出的肺癌干细胞分为对照组和观察组,每组30例。对照组不作任何处理,观察组采用替莫唑胺进行处理,对比两组对肺癌干细胞活力抑制情况、对肺癌干细胞迁移能力的影响以及A549-CSCs的细胞分化能力相关因子Sox2和Oct4的mRNA水平。结果观察组肺癌干细胞mRNA及蛋白表达量、Notch1、Hes1蛋白表达量低于对照组,观察组A549-CSCs的细胞分化能力相关因子Sox2和Oct4的mRNA水平低于对照组,差异有统计学意义(P<0.05)。结论基于Notch1/Hes1通路角度来看,替莫唑胺对于肺癌干细胞增殖、分化具有抑制作用,替莫唑胺主要是通过对肺癌干细胞Sox2、Oct4、mRNA蛋白表达产生抑制来实现上述功效。

关键词： Notch1/Hes1通路替莫唑胺肺癌干细胞增殖分化

小冲杆技术及其在材料与铅铋脆化效应研究中的应用

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中国腐蚀与防护学报 2024年第3期44卷 567-575页

作者：和雅洁陈灵芝阮章顺付晓刚纪琤龙斌中国原子能科学研究院、反应堆工程技术研究所北京102413

第四代反应堆中铅冷快堆是一种非常有发展前景的堆型。在铅冷快堆包壳材料设计时,需要重点考虑包壳材料与高温铅铋的相容性,关注其抗液态金属腐蚀能力,尤其是腐蚀介质与应力耦合时材料性能的变化。小冲杆实验(SPT)是一种使用小尺寸样品... 详细信息

第四代反应堆中铅冷快堆是一种非常有发展前景的堆型。在铅冷快堆包壳材料设计时,需要重点考虑包壳材料与高温铅铋的相容性,关注其抗液态金属腐蚀能力,尤其是腐蚀介质与应力耦合时材料性能的变化。小冲杆实验(SPT)是一种使用小尺寸样品评估材料服役条件下力学性能变化的实验方法,这种方法可以直接在正在使用的材料中提取样品而不损害其完整性,因此小冲杆测试非常适用于所研究材料数量有限或研究在役材料的情况。本文简要介绍了小冲杆测试技术,归纳了小冲杆测试与标准尺寸测试实验的相关性,阐述了使用小冲杆技术进行的关键材料力学性能研究,特别阐述了小冲杆测试在研究结构材料液态金属脆化效应(LME)方面的应用。结果可为小冲杆技术应用于研究材料液态铅铋脆化效应提供技术方法及理论支持。

关键词：小冲杆测试结构材料力学性能液态金属脆化效应

不同萝卜品种种子萌发期抗旱性综合评价及抗旱指标筛选

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西北农林科技大学学报（自然科学版） 2024年第8期52卷 70-81,90页

作者：摆福红王凯彬马小红王晓敏程国新郭猛高艳明李建设伏小刚宁夏大学葡萄酒与园艺学院宁夏银川750021 宁夏现代设施园艺工程技术研究中心宁夏银川750021 宁夏优势特色作物现代分子育种重点实验室宁夏银川750021 宁夏旺吉农牧业发展有限公司宁夏固原756000

【目的】综合评价30个萝卜品种种子萌发期抗旱性及筛选抗旱性鉴定指标,以筛选出适宜在宁夏半干旱地区种植的萝卜品种。【方法】以30个萝卜品种为试验材料,设置蒸馏水(对照)和15%PEG-6000溶液模拟干旱胁迫2个处理,测定不同处理下各萝卜... 详细信息

【目的】综合评价30个萝卜品种种子萌发期抗旱性及筛选抗旱性鉴定指标,以筛选出适宜在宁夏半干旱地区种植的萝卜品种。【方法】以30个萝卜品种为试验材料,设置蒸馏水(对照)和15%PEG-6000溶液模拟干旱胁迫2个处理,测定不同处理下各萝卜品种种子萌发期的发芽率、发芽势、发芽指数、活力指数等9个发芽指标,并通过相关性分析、主成分分析、隶属函数法、灰色关联度和聚类分析等相结合的方法,对供试萝卜品种进行萌发期抗旱性综合评价及抗旱指标筛选。【结果】与对照相比,干旱胁迫下供试萝卜品种各测定指标均受到不同程度的影响;大多数测试指标抗旱系数间存在显著或极显著相关性;基于主成分分析法将9个单项指标抗旱系数转化为2个主成分,其累计方差贡献率为78.18%。根据抗旱性度量值(D)、综合抗旱系数(CDC)值和加权抗旱系数(WDC)值大小对各品种抗旱性的排序结果相近。聚类分析在欧氏距离为10处可将30个萝卜品种分为4类,其中抗旱型品种3个、中度抗旱型品种8个、干旱敏感型品种14个和干旱极敏感型品种5个。灰色关联分析与逐步回归分析结果表明,相对活力指数、相对发芽率、相对根鲜质量、相对芽长、相对根长、相对芽鲜质量、相对发芽势、相对萌发指数和相对根冠比均可作为萝卜种子萌发期抗旱性鉴定指标。【结论】种子萌发期抗旱型萝卜品种为绿翡翠2号、超级满堂红和盛萃一号,该研究结果为萝卜种子萌发期抗旱性高效评价与抗旱品种选育及其推广应用提供参考。

关键词：种子萌发期抗旱品种抗旱指标萝卜育种

Developing an atmospheric aging evaluation model of acrylic coatings:A semi-supervised machine learning algorithm

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1617-1627页

作者： Yiran Li Zhongheng fu Xiangyang Yu Zhihui Jin Haiyan Gong Lingwei Ma xiaogang Li Dawei Zhang Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China BRI Southeast Asia Network for Corrosion and Protection(MOE) Shunde Innovation School of University of Science and Technology BeijingFoshan 528399China

To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in *** atmospheric aging evaluation model of acrylic coatings was developed based on aging data including11 environmental factors from 567 cities.A hybrid method of random forest and Spearman correlation analysis was used to reduce the redundancy and multicollinearity of the data set by dimensionality reduction.A semi-supervised collaborative trained regression model was developed with the environmental factors as input and the low-frequency impedance modulus values of the electrochemical impedance spectra of acrylic coatings in 3.5wt%NaCl solution as *** model improves accuracy compared to supervised learning algorithms model(support vector machines model).The model provides a new method for the rapid evaluation of the aging performance of acrylic coatings,and may also serve as a reference to evaluate the aging performance of other organic coatings.

关键词： acrylic coatings coatings aging atmospheric environment machine learning

Estrogen receptor gene polymorphism in a Chinese population with multiple sclerosis

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Neural Regeneration Research 2011年第19期6卷 1488-1492页

作者： Qingli Sun Ruping Xie Yu fu xiaogang Li Dongsheng Fan Department of Neurology Peking University Third Hospital Beijing 100191 China

This study sought to elucidate the role of the Pvull and Xbal polymorphisms of the estrogen receptor gene in 74 Chinese patients with multiple sclerosis, and 95 ethnicity-matched controls, using polymerase chain reaction-restriction fragment-length polymorphism analysis. The results revealed that the P allele of Pvull was significantly more prevalent in multiple sclerosis patients compared with controls （P = 0.019）. While distribution frequencies were significantly increased in female multiple sclerosis patients compared with female controls （P = 0.044）, no significant difference was observed between male patients and controls （P〉 0.05）. Frequencies of Ppxx genotypes were significantly higher in multiple sclerosis patients compared with controls （24.3% vs 12.8%, P = 0.025）. Genotypes and alleles of the estrogen receptor were not associated with age, number of attacks or expanded disability status scale scores of patients with multiple sclerosis. These findings indicate that the Pvull but not the Xbal polymorphism in the estrogen receptor gene is associated with susceptibility to multiple sclerosis in the Chinese population. In addition, women with P allele appear to be particularly susceptible to multiple sclerosis.

关键词： estrogen receptor gene polymorphism multiple sclerosis case-control study

A novel evasion guidance for hypersonic morphing vehicle via intelligent maneuver strategy

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Chinese Journal of Aeronautics 2024年第5期37卷 441-461页

作者： Xun LI xiaogang WANG Hongyu ZHOU Yu LI Department of Aerodynamics Harbin Institute of TechnologyHarbin 150001China Beijing Aerospace Technology Institute Beijing 100074China

This paper presents a novel evasion guidance law for hypersonic morphing vehicles,focusing on determining the optimized wing's unfolded angle to promote maneuverability based on an intelligent ***,the pursuit-evasion problem is modeled as a Markov decision *** the agent's action consists of maneuver overload and the unfolded angle of wings,which is different from the conventional evasion guidance designed for fixed-shape *** reward function is formulated to ensure that the miss distances satisfy the prescribed bounds while minimizing energy ***,to maximize the expected cumulative reward,a residual learning method is proposed based on proximal policy optimization,which integrates the optimal evasion for linear cases as the baseline and trains to optimize the performance for nonlinear engagement with multiple ***,offline training guarantees improvement of the constructed evasion guidance law over conventional ***,the guidance law for online implementation includes only analytical *** maps from the confrontation state to the expected angle of attack and the unfolded angle while retaining high computational *** show that the proposed evasion guidance law can utilize the change of unfolded angle to extend the maximum overload *** it surpasses conventional maneuver strategies by ensuring better evasion efficacy and higher energy efficiency.

关键词： Hypersonic vehicles Variable-sweep wings Evasion guidance Reinforcement learning Pursuit-evasion problem