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微波法快速、原位合成NiFe LDH纳米片阵列用于高效电催化水氧化

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科学通报 2025年第2期70卷 193-204页

作者：王沙沙陆徐云常亚楠李晓萱刘影包建春南京师范大学化学与材料科学学院南京210023

氧气析出反应(oxygen evolution reaction,OER)复杂的动力学和高能量势垒严重制约了电解水生产氢能的效率.基于此,本工作报道了一种简单、高效的微波合成策略,可以在碳布表面快速、原位生长层状双金属氢氧化物阵列(layered double hydro... 详细信息

氧气析出反应(oxygen evolution reaction,OER)复杂的动力学和高能量势垒严重制约了电解水生产氢能的效率.基于此,本工作报道了一种简单、高效的微波合成策略,可以在碳布表面快速、原位生长层状双金属氢氧化物阵列(layered double hydroxide/carbon cloth,LDH/CC),用以提升OER性能.研究发现,溶剂类型对LDHs的原位生长起着至关重要的作用.相比于纯水、乙二醇水溶液和季戊四醇水溶液溶剂,丙三醇水溶液具有适宜的极性,可以有效调控金属离子的表面能和反应过程中金属离子的成核/迁移,进而促进LDHs在碳布表面的原位、均匀生长.与传统的水热法和电沉积法相比,微波法合成的NiFe LDH/CC具有氧缺陷含量高、电化学活性位点丰富、界面电荷转移电阻低和内在活性高等优点.以OER为探针反应,探究并比较了以不同溶剂及合成方法制得的NiFe LDH/CC的电催化性能.测试表明,以丙三醇水溶液为溶剂、采用微波法合成的NiFe LDH/CC性能最好,在100 mA cm^(-2)的过电位(overpotential,η)仅为257 mV(η_(100)),400 mA cm^(-2)的过电位仅为331 mV(η_(400)),持续测试100 h后性能仍保持95%,显著优于以乙二醇水溶液(287和386 mV)、季戊四醇水溶液(309和406 mV)为溶剂的对比样,以及水热法(279和434 mV)、电沉积法(293和380 mV)合成NiFe LDH/CC的电催化性能.进一步,这些性能优于近些年报道的很多过渡金属化合物.这种微波合成策略不仅适用于NiFe LDH,还可以原位合成NiMn LDH、CoFe LDH、NiCo LDH,为高活性LDH的原位、快速合成提供了一种新方法.

关键词：电催化氧气析出反应微波法 NiFe层状双金属氢氧化物

Offspring of aged mothers of rotifer Brachionus calyciflorus shows lower sexual propensity than their elder siblings under crowded conditions

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Journal of Oceanology and limnology 2019年第5期37卷 1604-1610页

作者： li Wenjie NIU Cuijuan li xiaoxuan Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University

Maternal eff ects are one of the most interesting topics in evolutionary ecology as they can aff ect the rate of evolution and population dynamics by phenotypic manipulation of off spring related to fi tness. At present, studies examining the interaction between maternal environment eff ects and maternal age (birth order) eff ects are scarce. We designed an experiment to reveal whether environmentally induced maternal manipulation works equally on off spring across birth orders in rotifer Brachionus calycifl orus. In the experiment, newborn amictic mothers (F0) were cultured parallelly in low (LD) and high (HD) population density. Off spring (F1) of young (YF0) and old (OF0) mothers in both LD and HD groups were cultured under a crowded condition and the mixis ratios of both F1 and F2 were examined. Results show that F1 from HD-YF0 had a signifi cantly higher mixis ratio and those amictic ones produced daughters (F2 ) with higher mixis ratio in response to crowding than those from HD-OF0. In contrast, no such diff erences among F1 siblings were found in the LD-F0 group. Therefore, the eff ect of maternal age on the sexual propensity of the off spring can be aff ected independently by the maternal population density.

关键词： rotifer Brachionus calycifl orus sexual propensity birth order eff ect maternal environment mixis ratio

宽温高湿环境下油水两相O形液压杆封性能分析

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润滑与密封 2025年第1期50卷 1-10页

作者：王冰清李晓暄彭旭东李运堂陈源金杰中国计量大学机电工程学院浙江杭州310018 浙江工业大学机械工程学院浙江杭州310023

针对宽温高湿环境下液压油受水污染而使密封处于油包水两相润滑状态,建立油包水流型下油水两相液压杆封热弹流混合润滑模型,探究宽温环境和含水率对油水两相O形液压杆封静力学特性、密封行为及密封性能的影响机制与规律。研究结果表明:... 详细信息

针对宽温高湿环境下液压油受水污染而使密封处于油包水两相润滑状态,建立油包水流型下油水两相液压杆封热弹流混合润滑模型,探究宽温环境和含水率对油水两相O形液压杆封静力学特性、密封行为及密封性能的影响机制与规律。研究结果表明:在油包水流型下,含水率增大时,油水混合物黏度略增大,流体动压效应增强,净泄漏率减小,摩擦力减小,密封润滑特性及性能均提升;低温环境下,密封挤压变形小,液膜黏度大,流体动压效应强,净泄漏率虽小但摩擦力大;高温环境下,密封挤压变形大,诱发局部应力集中,液膜黏度小,流体动压效应弱,净泄漏率大;环境温度对密封性能影响十分显著,特别是高温高速或高温高压工况下,净泄漏率明显增大。

关键词：液压杆封油水两相流液压系统宽温高湿环境密封性能静力学特性

Effects of air plasma flame on the ZrB_(2)-based UHTC coatings:Microstructure,phase evolution and ablation resistance

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Journal of Materials Science & Technology 2023年第27期158卷 194-206页

作者： Dou Hu Qiangang Fu Lei Zhou xiaoxuan li Bing liu State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Fiber Reinforced Light-Weight CompositesNorthwestern Polytechnical UniversityXi’an 710072China

As for the air plasma sprayed ZrB_(2)-based coatings,B content change caused by inevitable oxidation is predictable but commonly *** by air plasma flame,the B element loss and residual B_(2) O_(3) in the sprayed ZrB_(2) coating were ***,how the B content change affects the microstructure,phase evolution,and ablation resistance(2.4 MW/m^(2),60 s)of ZrB_(2)-based coatings with different sec-ondary phases(SiC,MoSi_(2),and TaC)was *** B element loss contributed to the increase in surface temperature and the decline in the sintering degree of the ZrO_(2) *** evaporation of residual B_(2)O_(3) caused damage to the coating structure in the form of pores,whose negative effect was enhanced and reduced by MoSi_(2) and TaC secondary phases,*** work will provide some insight into thermally sprayed non-oxide ceramic coatings in the atmosphere.

关键词： Plasma spraying UHTCs Ablation behavior Microstructure ZrB_(2)

Practice and Challenge of International Peer Review: A Case Study of Research Evaluation of CAS Centers for Excellence

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Journal of Data and Information Science 2019年第3期4卷 22-34页

作者： Fang Xu xiaoxuan li Institutes of Science and Development Chinese Academy of Sciences Beijing 100090 China School of Public Policy and Management University of Chinese Academy of Sciences Beijing 100049 China

Purpose: The main goal of this paper is to show that international peer review can work in China’s context with satisfactory outcomes. Moreover, this paper also provides a reference for the practice of science and technology ***/methodology/approach: This paper starts with a discussion of two critical questions about the significance and design of international peer review. A case study of international peer review of CAS Centers for Excellence is further analyzed. Findings: International peer review may provide a solution to address the problem of quantitative oriented research evaluation in China. The case study of research evaluation of CAS Centers for Excellence shows that it is possible and feasible to conduct an international peer review in China’s context. When applying this approach to other scenarios, there are still many issues to consider including individualized design of international peer review combined with practical demands, and further improvement of theories and methods of international peer review. Research limitation: 1) Only the case of international peer review of CAS Centers for Excellence is analyzed;2) A relatively small number of respondents were surveyed in the questionnaire. Practical implications: The work presented in this study can be used as a reference for future ***/value: Currently, there are no similarly detailed studies exploring the significance and methodology of international peer review in China.

关键词： Chinese Academy of Sciences CAS Centers for Excellence International peer review Research evaluation

不锈钢细长管内表面卧式单向旋转磨粒流加工研究

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组合机床与自动化加工技术 2025年第1期 213-217,222页

作者：李晓璇白小云李文辉李秀红刘静怡温学杰太原理工大学机械与运载工程学院太原030024 太原理工大学航空航天学院太原030024 太原理工大学精密加工山西省重点实验室太原030024

以304不锈钢细长管为研究对象,采用卧式单向旋转磨粒流加工技术对细长管内表面进行加工。基于FLUENT仿真软件,探究不同流道形状和不同粘度磨料对磨粒流加工效果的影响,设计正交实验研究工件转速、磨粒目数、磨粒浓度和加工次数对表面粗... 详细信息

以304不锈钢细长管为研究对象,采用卧式单向旋转磨粒流加工技术对细长管内表面进行加工。基于FLUENT仿真软件,探究不同流道形状和不同粘度磨料对磨粒流加工效果的影响,设计正交实验研究工件转速、磨粒目数、磨粒浓度和加工次数对表面粗糙度下降率以及沿细长管长度方向加工均匀性的影响。结果表明,增加加工次数和给细长管施加旋转运动,可以提高细长管沿长度方向的加工均匀性;加工次数对细长管表面粗糙度下降率影响最大,工件转速对细长管沿长度方向的加工均匀性影响最大。经卧式单向旋转磨粒流加工后,细长管内表面的表面粗糙度由Ra 1.57μm降到Ra 0.7μm,表面粗糙度下降率达到53.2%,进出口表面粗糙度下降率差值为1.67%。

关键词：卧式单向旋转磨粒流不锈钢细长管数值模拟正交实验表面粗糙度

整体式催化剂在CO-PROX反应中的设计及应用研究进展

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低碳化学与化工 2025年第2期50卷 100-112,126页

作者：王晴李维国李智刘园园孙宗壮李晓旋脱永笑冯翔中国石油大学(华东)化学化工学院山东青岛266580 山东能源集团有限公司大型煤气化及煤基新材料国家工程研究中心山东济南273500 中国石油大学(华东)新能源学院山东青岛266580

CO优先氧化(CO-PROX)反应是燃料电池H_(2)净化的关键步骤,对于提高燃料电池效率和减少有害排放具有重要意义。整体式催化剂因具有良好的热稳定性和抗聚集性、较低的压降、较高的机械强度和较好的传质传热特性而逐渐成为研究热点。综述了... 详细信息

CO优先氧化(CO-PROX)反应是燃料电池H_(2)净化的关键步骤,对于提高燃料电池效率和减少有害排放具有重要意义。整体式催化剂因具有良好的热稳定性和抗聚集性、较低的压降、较高的机械强度和较好的传质传热特性而逐渐成为研究热点。综述了CO-PROX反应整体式催化剂(金属整体式催化剂、陶瓷整体式催化剂和3D打印聚合物整体式催化剂)的研究进展,重点分析了整体框架和催化剂涂层制备技术等对其催化性能的影响,并对比了不同类型CO-PROX反应整体式催化剂的优缺点。分析了CO-PROX反应整体式催化剂目前面临的挑战,并对其未来研究方向进行了展望。

关键词： CO优先氧化反应整体式催化剂燃料电池整体框架催化剂涂层

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Cyclodextrin derivatives functionalized highly sensitive chiral sensor based on organic field-effect transistor

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Chinese Chemical Letters 2020年第1期31卷 99-102页

作者： Yifan Wu Xuepeng Wang xiaoxuan li Yin Xiao Yong Wang School of Chemical Engineering and Technology Tianjin Engineering Research Center of Functional Fine ChemicalsTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China

Novel highly sensitive chiral organic field-effect transistors(COFET)were developed by directly assembling imidazolium3,5-dimethylphenylcabamoylated-β-cyclodextrin(lm^+-Ph-β-CD)and 3,5-dimethylphenylcarbamoylated-β-CD(Ph-β-CD)respectively onto the semiconductor layer as sensing *** Im+-Ph-β-CD/COFET afforded better enantioselectivity and a lowest detection concentration of10^-18 L/mol as well as the potentiality in quantitative analysis of commercial medicines.

关键词： Chiral discrimination OFET Sensor β-Cyclodextrin derivatives Real-time detection Quantitative detection

Study on Decoloration of Acidic Scarlet GR by Pyrolusite Oxidation under an Acid Condition

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Acta Geologica Sinica(English Edition) 2006年第2期80卷 257-261页

作者： CHEN Gang QING Chengsong CHEN Tianhu li xiaoxuan SONG Yinxian PENG Shuchuan School of Natural Resources and Environmental Engineering Hefei University of Technology Hefei Anhui 230009 School of Chemical Engineering Hefei University of Technology Hefei Anhui 230009

Decoloration of acidic scarlet GR by pyrolusite is studied in this paper. The effects of pH in solution, dosage and granularity of pyrolusite, reaction temperature, and vibration speed on decoloration efficiency are discussed. According to experiment results, the decoloration efficiency may exceed 95% for 40 mg/L GR solution by pyrolusite, pH is most important among all factors which impact the decoloration of acidic scarlet GR. Dosage and granularity of pyrolusite, reaction temperature, and vibration speed have a little benitfit on decoloration. The high decoloration efficiency and low removal efficiency of COD as well as FT-IR spectra of products between pyrolusite and acidic scarlet GR indicate that acidic scarlet GR undergoes the redox reaction on the interface of mineral and its chromophore is oxidated and decolored, but it is not removed thoroughly by oxidation.

关键词： pyrolusite acid dye chemical oxidation environmental mineralogy