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Pt single atoms coupled with Ru nanoclusters enable robust hydrogen oxidation for high-performance anion exchange membrane fuel cells

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Nano Research 2024年第7期17卷 6147-6156页

作者： Jianmei Wang Bingxing Zhang Xiaozhong Zheng Xuerui Liu wei Guo Zhouxin luo Yongfeng Liu Mingxia Gao Jian Chen Zhongbin Zhuang Hongge Pan Wenping Sun School of Materials Science and Engineering Zhejiang UniversityHangzhou 310058China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China State Key Lab of Organic–Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an 710021China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China

The sluggish reaction kinetics of alkaline hydrogen oxidation reaction(HOR)is one of the key challenges for anion exchange membrane fuel cells(AEMFCs).To achieve robust alkaline HOR with minimized cost,we developed a single atom-cluster multiscale structure with isolated Pt single atoms anchored on Ru nanoclusters supported on nitrogen-doped carbon nanosheets(Pt1-Ru/NC).The well-defined structure not only provides multiple sites with varied affinity with the intermediates but also enables simultaneous modulation of different sites via interfacial *** addition to weakening Ru–H bond strength,the isolated Pt sites are heavily involved in hydrogen adsorption and synergistically accelerate the Volmer step with the help of Ru ***,this catalyst configuration inhibits the excessive occupancy of oxygen-containing species on Ru sites and facilitates the HOR at elevated *** Pt1-Ru/NC catalyst exhibits superior alkaline HOR performance with extremely high activity and excellent *** AEMFC with a 0.1 mg·cmPGM^(−2)loading of Pt1-Ru/NC anode catalyst achieves a peak powder density of 1172 mW·cm^(−2),which is 2.17 and 1.55 times higher than that of Pt/C and PtRu/C,*** work provides a new catalyst concept to address the sluggish kinetics of electrocatalytic reactions containing multiple intermediates and elemental steps.

关键词： nanoclusters multiscale structure hydrogen oxidation reaction electrocatalysis anion exchange membrane fuel cells

Research on the Importance of Monetary Work to the Political Development of the Western Hunan and Hubei Base Areas

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Journal of Finance Research 2020年第2期4卷 124-127页

作者： jun wei College of Marxism Minnan Normal UniversityZhangzhouFujian363000China

During the seven years revolution in the Western Hunan Hubei revolutionary base,currency experienced four stages of construction and development,and became the economic tool of revolutionary regime,and made considerable contribution;however,the importance of politics to financial work is obvious *** to the mistakes caused by the left leaning in the revolutionary work,the monetary work in the revolutionary base area in Western Hunan and Hubei has been seriously affected the final result of the influence is to withdraw from the circulation field with the transfer of the main body of the revolutionary team.

关键词： Currency and politics Western Hunan and Hubei Reflection of revolution

Enhanced graph-based fault diagnostic system for nuclear power plants

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Nuclear Science and Techniques 2019年第12期30卷 8-21页

作者： Yong-Kuo Liu Xin Ai Abiodun Ayodeji Mao-Pu Wu Min-jun Peng Hong Xia wei-Feng Yu State Key Laboratory of Nuclear Power Safety Monitoring Technology and Equipment Shenzhen 518172GuangdongChina Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin Engineering UniversityHarbin 150001China Lianyungang JARI Deepsoft Technology Co. Ltd.Lianyungang 222002China

Scheduled maintenance and condition-based online monitoring are among the focal points of recent research to enhance nuclear plant *** of the most effective ways to monitor plant conditions is by implementing a full-scope,plant-wide fault diagnostic ***,most of the proposed diagnostic techniques are perceived as unreliable by operators because they lack an explanation module,their implementation is complex,and their decision/inference path is *** formalism has been considered for fault diagnosis because of its clear decision and inference modules,and its ability to display the complex causal relationships between plant variables and reveal the propagation path used for fault localization in complex ***,in a graphbased approach,decision-making is slow because of rule *** this paper,we present an enhanced signed directed graph that utilizes qualitative trend evaluation and a granular computing algorithm to improve the decision speed and increase the resolution of the graphical *** integrate the attribute reduction capability of granular computing with the causal/fault propagation reasoning capability of the signed directed graph and comprehensive rules in a decision table to diagnose faults in a nuclear power *** trend analysis is used to solve the problems of fault diagnostic threshold selection and signed directed graph node state *** similarity reasoning and detection ability of the granular computing algorithm ensure a compact decision table and improve the decision *** performance of the proposed enhanced system was evaluated on selected faults of the Chinese Fuqing 2 nuclear *** proposed method offers improved diagnostic speed and efficient data *** addition,the result shows a considerable reduction in false positives,indicating that the method provides a reliable diagnostic system to support further intervention by operators.

关键词： Nuclear power plants Fault diagnosis Signed directed graph Decision table Granular computing

Effect of homojunction structure in boosting sodium-ion storage: The case of MoO_(2)

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Journal of Energy Chemistry 2023年第3期78卷 115-122,I0004页

作者： Sheng Li wei Zhang Yingxue Cui Jianmin Ma Hong-Jie Peng jun Li Xianhu Liu Dickon HLNg Xinyan Liu Jiabiao Lian Institute for Energy Research Jiangsu UniversityZhenjiang 212013JiangsuChina School of Physics and Electronics Hunan UniversityChangsha 410082HunanChina Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina Key Laboratory of Materials Processing&Mold(Zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhou 450002HenanChina School of Science and Engineering The Chinese University of Hong Kong(Shenzhen)LonggangShenzhen 518172GuangdongChina

High-efficiency sodium-ion batteries(SIBs) are in great demand for energy storage applications,which are dominated by the Na+storage performance of electrode ***,a one-pot solvothermal method is developed to construct amorphous/crystalline MoO_(2)(a/c-MoO_(2)) homojunction for boosting Na+*** simulations signify that electrons redistribute at the homogenous interface of a/c-MoO_(2),resulting in an inbuilt driving force to easily adsorb charge carriers and promote the electron/ion transfer *** on its crystallographic superiorities,the a/c-MoO_(2)homojunction with high Na adsorbability(-1.61 eV) and low Na diffusion energy barrier(0.519 eV) achieves higher capacity(307 mA h g^(-1)at 0.1 A/g),better rate capability and cycling stability than either a-MoO_(2)or c-MoO_(2)*** in-situ X-ray diffraction(XRD) and ex-situ X-ray photoelectron spectroscopy(XPS)techniques,the ’adsorption-insertion-conversion’ mechanism is well established for Na+storage of MoO_(2).Our work opens new opportunities to optimize electrode materials via crystallographic engineering for efficient Na+storage,and helps to better understand the effects of homojunction structure in enhanced electrochemical performance.

关键词： MoO_(2)homojunction Crystallographic engineering Theoretical calculations In-situ XRD Na^(+)storage mechanism

Contact performance analysis of pressure controller's sealing interface in deep in-situ pressure-preserved coring system

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Petroleum Science 2022年第3期19卷 1334-1346页

作者： Jia-Nan Li jun Wang Yun-Qi Hu Zhen-Xi You Meng Xu Ying-wei Wang Zu-Jie Zou Qi-Yue Kang School of Mechanical Engineering MOE Key Laboratory of Deep Underground Science and EngineeringCollege of Water Resource and HydropowerSichuan UniversityChengdu610065China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen518061China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization Pingdingshan Tianan Coal Mining Co.LTD.Pingdingshan467000China Xi'an Research Institute China Coal Technology&Engineering Group CorpXi'an710077China

The sealing performance of contact interfaces plays the most important role in the design and operation of the in-situ pressure-preserved coring *** meet the demand of ultra-high pressure-retained coring for oil and gas exploration in deep reservoirs,a quantitative analysis of the contact mechanical behavior of the pressure controller was *** on the micro-contact theory of rough surfaces,a three-dimensional numerical model of the rough contact interface between the valve cover and the valve seat was constructed,and the micro-contact behavior of the metal contact surfaces was comprehensively *** results show that the actual contact area of the valve interface increases with the increase of surface roughness before the critical contact point,but decreases after *** with the real contact model with double rough surfaces,although the simplified hard-contact model with a single rough surface can reflect the micro-contact behavior of the rough surface to a certain extent,it cannot truly reveal the microchannel morphology between the sealing interfaces under ***,the realistic double-rough-surface model should be recommended to evaluate the sealing performance of coring tools,particularly for high pressure *** material properties of valves have a significant effect on the contact characteristics of rough surfaces,which suggested that the actual contact area decreases with the increase of the elastic modulus of the contact material under the same loading *** knowledge of this work could help to enhance the seal design of pressure controllers for in-situ pressure-preserved coring.

关键词： In-situ pressure-preserved coring Metal seal Rough surface Micro contact

Separation of Sc_(2)O_(3) from Bayan Obo tailings through an innovative roasting method

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Rare Metals 2022年第3期41卷 1071-1076页

作者： Xin-jun Bao Zhi-Jian Wang Liu-Jiang Xi Ji-Bo Liu Zheng-Fu Su Tao Yang wei Cheng De-Bi Zhou Institute for Energy-Storing Materials Research Hunan Rare Earth Metal Material Research InstituteChangsha 410126China College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083China School of Metallurgical Engineering Hunan University of TechnologyZhuzhou 412007China

Sc_(2)O_(3)was successfully extracted and separated from Bayan Obo tailings by a CaCl_(2)-reductive carbon powder-combinative roasting *** optimum pro-cess condition was obtained through adjusting specific ef-fect *** is found that Sc_(2)O_(3)with the ratio of 87.51%is leached out under roasting temperature of 800℃for 2 h through adding 73%CaCl_(2),and 20%reductive carbon powder with liquid to solid ratio of ***,the specific reaction mechanism during roasting process was investi-gated by thermogravimetric–differential scanning calorimetry(TG-DSC)and X-ray diffraction(XRD)*** results show that the main phases(SiO_(2),CaF_(2) and NaFeSi_(2)O_(6))as well as important phases(LiScSi_(2)O_(6),REFCO_(3)and REPO_(4))would turn into new phases(CaFe-SiO_(4),Fe,Ca_(3)(PO_(4))_(2),NaCl,RE_(2)O_(3)and Sc_(2)O_(3))after com-plicated reactions,which effectively break up the original mineral compositions and activate the existing state of containing scandium matter,consequently facilitating the subsequent hydrochloric acid leaching process.

关键词： Bayan Obo tailings Roasting Decomposition Sc_(2)O_(3)

Endoscopic ultrasonography for staging of T1a and T1b esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2014年第5期20卷 1340-1347页

作者： Long-jun He Hong-Bo Shan Guang-Yu luo Yin Li Rong Zhang Xiao-Yan Gao Guo-Bao Wang Shi-Yong Lin Guo-Liang Xu Jian-jun Li Department of Endoscopy Sun Yat-sen University Cancer Center Guangdong Esophageal Cancer Institute Department of Endoscopy State Key Laboratory of Oncology in South China Department of Endoscopy Collaborative Innovation Center for Cancer Medicine

AIM: To investigate the accuracy of Endoscopic ultrasound (EUS) in staging and sub-staging T1a and T1b esophageal squamous cell carcinoma (ESCC).

关键词： Endoscopic ultrasound Esophageal cancer Squamous carcinoma Early cancer Stage

Incomplete reproductive isolation between Rhododendron taxa enables hybrid formation and persistence

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Journal of Integrative Plant Biology 2019年第4期61卷 433-448页

作者： Li-jun Yan Kevin S.Burgess wei Zheng Zhi-Bin Tao De-Zhu Li Lian-Ming Gao Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of Botany the Chinese Academy of Sciences Germplasm Bank of Wild Species Kunming Institute of Botany the Chinese Academy of Sciences Kunming College of Life Science University of the Chinese Academy of Sciences College of Vocational and Technical Education Yunnan Normal University Department of Biology College of Letters & Sciences Columbus State University University System of Georgia

The evolutionary consequences of hybridization ultimately depend on the magnitude of reproductive isolation between hybrids and their parents. We evaluated the relative contributions of pre-and post-zygotic barriers to reproduction for hybrid formation, hybrid persistence and potential for reproductive isolation of hybrids formed between two Rhododendron species,R. spiciferum and R. spinuliferum. Our study established that incomplete reproductive isolation promotes hybrid formation and persistence and delays hybrid *** pre-zygotic barriers to reproduction leading to hybrid formation are incomplete: parental species have overlapping flowering; they share the same pollinators;reciprocal assessments of pollen tube germination and growth do not differ among parents. The absence of post-zygotic barriers between parental taxa indicates that the persistence of hybrids is likely. Reproductive isolation was incomplete between hybrids and parents in all cases studied, although asymmetric differences in reproductive fitness were prevalent and possibly explain the genetic structure of natural hybrid swarms where hybridization is known to be bidirectional but asymmetric. Introgression, rather than speciation, is a probable evolutionary outcome of hybridization between the two Rhododendron taxa. Our study provides insights into understanding the evolutionary implications of natural hybridization in woody plants.

关键词： Incomplete reproductive isolation Rhododendron taxa

Homogenization heat treatment of Mg-7.0 wt%Y-1.0 wt%Nd-0.5 wt%Zr alloy

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Rare Metals 2020年第10期39卷 1196-1201页

作者： Jing-Bao Liu Kui Zhang Jing-Tao Han Xing-Gang Li Yong-jun Li Ming-Long Ma Jia-wei Yuan Meng Li State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous MetalsBeijing 100088 China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The microstructures and mechanical properties of Mg-7.0 wt%Y-1.0 wt%Nd-0.5 wt%Zr magnesium alloy were investigated both in as-cast condition and after homogenization heat treatment by differential scanning calorimetry(DSC),optical microscopy(OM),X-ray diffraction(XRD),scanning electron microscopy(SEM)and hardness *** results indicate that the ascast alloy consists ofα-Mg matrix,Mg24 Y5 and Mg41 Nd5 phases,which are eutectic phases(cubic Y-rich phase).With the increase in homogenization temperature and time,the Mg24 Y5 and Mg41 Nd5 phases are completely dissolved into matrix,and only yttrium of intermetallic compounds leaves around *** homogenization heat treatment,the elements distributed uniformly and the grains grow up not obviously,only yttrium element of intermetallic compounds left around *** optimum homogenization condition is at 537℃for 16 *** mechanical properties are improved after homogenization,with tensile strength ofσb=181 MPa,yielding strength ofσ(0.2)=144 MPa and elongation ofδ=5.5%,which are better than those of as-cast alloy.

关键词： Rare earth magnesium alloy Homogenization Microstructure Hardness