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Carbon Energy 2024年第8期6卷 122-133页

作者： Jian‐Zhao Peng Yin‐Long li Yao‐Ti Cheng Fu‐Zhi li Bo Cao Qing Wang xian Yue Guo‐Tao Lai Yang‐Gang Wang Jun Gu Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdongChina Institute for Catalysis Hokkaido UniversitySapporoJapan

Metal–N–C single‐atom catalysts,mostly prepared from pyrolysis of metalorganic precursors,are widely used in heterogeneous *** metal sites with diverse local structures coexist in this type of material and it is challenging to characterize the local structure,a reliable structure–property relationship is difficult to *** macrocyclic complexes adsorbed on carbon support are well‐defined models to mimic the singleatom ***–N_(4)site with four electroneutral pyridine‐type ligands embedded in a graphene layer is the most commonly proposed structure of the active site of single‐atom catalysts,but its molecular counterpart has not been *** this work,we synthesized the conjugated macrocyclic complexes with a metal center(Co,Fe,or Ni)coordinated with four electroneutral pyridinic ligands as model catalysts for CO_(2)*** comparison,the complexes with anionic quadri‐pyridine macrocyclic ligand were also *** Co complex with the electroneutral ligand expressed a turnover frequency of CO formation more than an order of magnitude higher than that of the Co complex with the anionic *** ab initio molecular dynamics simulations based on the well‐defined structures of the model catalysts indicate that the Co complex with the electroneutral ligand possesses a stronger ability to mediate electron transfer from carbon to CO_(2).

关键词： ab initio molecular dynamics CO_(2)reduction electrocatalysis model catalyst single‐atom catalyst

A mixed-valence polyoxometalate-based 3D inorganic framework cathode material for high-efficiency rechargeable AZIBs

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Rare Metals 2024年第8期43卷 3677-3691页

作者： Qing Han Hao-Ran Xiao Tao Zhou Bing-Chuan li liu Yang ling-ling Xie Xue-Jing Qiu xian-Yong Wu li-Min Zhu Xiao-Yu Cao School of Chemistry and Chemical Engineering Henan University of TechnologyZhengzhou 450001China Key Laboratory of High Specific Energy Materials for Electrochemical Power Sources of Zhengzhou City Zhengzhou 450001China College of Materials Engineering Henan University of EngineeringZhengzhou450007China School of Environmental Engineering Henan University of TechnologyZhengzhou 450001China Department of Chemistry University of Puerto Rico-Rio Piedras CampusSan JuanPR 00925USA

The global trend towards new energy storage systems has stimulated the development of electrochemical energy storage *** these technologies,rechargeable aqueous zinc-ion batteries(AZIBs)have attracted considerable interest as a potential alternative to lithium-ion batteries(liBs)due to their affordable cost,environmental compatibility and high safety *** this study,a high-quality electrode for AZIBs has been successfully developed using a dehydrated mixed-valence polyoxometalate-based three-dimensional(3D)inorganic framework material known as[H_6Mn_(3)V^Ⅳ_(15)V-^Ⅴ_(4O)_(46)(H_2O)_(12)](3D-MnVO).This innovative 3D-MnVO material is built from the alternate connections of{V_(19)O_(46)}"sphere-shaped"clusters andμ_(2)-{Mn(H_(2)O)_(4)}bridges,where each{V_(19)O_(46)}cluster is surrounded by three pairs of vertically distributed{Mn(H_(2)O)_(4)}units,thus resulting in the 3D interpenetrating grid-like network from the infinite[-{V_(19)O_(46)}-μ_(2)-Mn(H_(2)O)_(4)-{V_(19)O_(46)}]_∞chains in three mutually perpendicular *** 3D framework structure of 3D-MnVO possesses abundant oxygen vacancies,spacious and multi-level interconnected channels for ion transport,which facilitates the efficient intercalation/deintercalation of hydrated Zn^(2+)into the pores of the primary structure via the intercalation capacitance *** a result,the 3D-MnVO electrode exhibits excellent diffusion rates and minimal interfacial *** a current density of 0.1 A·g^(-1),the 3D-MnVO cathode delivers a commendable discharge capacity of170.5 mAh·g^(-1)with 81.6%capacity retention after100 charge/discharge ***,even at a high current density of 1.0 A·g^(-1),the 3D-MnVO electrode delivers a remarkable reversible capacity of198.9 mAh·g^(-1).Our research results provide valuable insights into the development of advanced polyoxometalate-based 3D inorganic framework electrode materials for high-performance rechargeable AZIBs.

关键词： Cathode Polyoxometalate 3D inorganic framework Zinc-ion batteries Energy storage mechanism

Electrochemical reconstruction: a new perspective on Sn metal-organic complex microbelts as robust anode for lithium storage

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Rare Metals 2024年第1期43卷 76-86页

作者： Jin-Ke Shen Nai-Teng Wu li-Yuan Wang Gang Jiang Dong-Lei Guo Jin li Gui-Long liu Hong-Yu Mi Huan Pang xian-Ming liu Key Laboratory of Function-oriented Porous Materials of Henan Province College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources School of Chemical Engineering and TechnologyXinjiang UniversityUrumqi 830046China School of Chemistry and Chemical Engineering Institute for Innovative Materials and EnergyYangzhou UniversityYangzhou 225009JiangsuChina

Tin-based materials with high theoretical capacity and suitable working voltage are ideal anode materials for lithium-ion batteries(liBs). However, to overcome their shortcomings(volume expansion and inferior stability), the preparation processes are usually complicated and expensive. Herein, a tin-based metal-organic complex(tin 1,2-benzenedicarboxylic acid, Sn-BDC)with one-dimensional microbelt morphology is synthesized by a facile, rapid and low-cost co-precipitation method, and served as anode material for liBs without any post-treatment. Sn-BDC exhibits a high reversible capacity with609/440 m Ah·g^(-1) at 50/2000 m A·g^(-1), and robust cycling stability of 856 m Ah·g^(-1) after 200 cycles at 200 m A·g^(-1),which are obviously superior to that of the Sn Ox/C counterparts. Moreover, an electrochemical reconstruction perspective on the lithium storage mechanism of Sn-BDC is proposed by systematic ex-situ characterizations. The reconstructed SnO_(2) replaces Sn-BDC and becomes the active material in the subsequent cycles. As the by-product of the lithiation reaction, the formed li-based metal-organic complex(li-BDC, wrapped around the reconstructed SnO_(2)) plays an important role in alleviating volume expansion and accelerating the charge transfer *** work is beneficial to design and construct the new electrode materials based on the electrochemical reconstruction for advanced liBs.

关键词： Electrochemical reconstruction Metal-organic complex Anode lithium storage mechanism lithium-ion batteries

Thermally-induced cracking behaviors of coal reservoirs subjected to cryogenic liquid nitrogen shock

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2894-2908页

作者： Songcai Han Qi Gao Xinchuang Yan lile li Lei Wang xian Shi Chuanliang Yan Daobing Wang College of Energy Chengdu University of TechnologyChengdu610059China School of Engineering The University of Western Australia35 Stirling HighwayPerthWA6009Australia School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China School of Mechanical Engineering Beijing Institute of Petrochemical TechnologyBeijing102617China

The benefits of using cryogenic liquid nitrogen shock to enhance coal permeability have been confirmed from experimental *** this paper,we develop a fully coupled thermo-elastic model in combination with the strain-based isotropic damage theory to uncover the cooling-dominated cracking behaviors through three typical cases,*** reservoirs containing a wellbore,a primary fracture,and a natural fracture network,*** progressive cracking processes,from thermal fracture initiation,propagation or cessation,deflection,bifurcation to multi-fracture interactions,can be well captured by the numerical *** is observed that two hierarchical levels of thermal fractures are formed,in which the number of shorter thermal fractures consistently exceeds that of the longer *** effects of coal properties related to thermal stress levels and thermal diffusivity on the fracture morphology are quantified by the fracture fractal dimension and the statistical fracture *** induced fracture morphology is most sensitive to changes in the elastic modulus and thermal expansion coefficient,both of which dominate the complexity of the fracture *** reservoir candidates with preferred thermal-mechanical properties are also recommended for improving the stimulation *** findings are that there exists a critical injection temperature and a critical in-situ stress difference,above which no thermal fractures would be *** natural fractures with higher density and preferred orientations are also essential for the formation of complex fracture *** obtained results can provide some theoretical support for cryogenic fracturing design in coal reservoirs.

关键词： Coal reservoirs Cryogenic shock Thermal cracking behaviors Fracture morphology

Microstructure and water-swelling mechanism of red-bed mudstone in the Xining region,Northeastern Tibetan Plateau

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2537-2551页

作者： Huan Guan Yong Ren Sixiang ling Xiyong Wu Tao Yu xian li Sen Wang Chunwei Sun School of Civil Engineering Southwest Jiaotong UniversityChengdu610031China Faculty of Geosciences and Engineering Southwest Jiaotong UniversityChengdu611756China Moe Key Laboratory of High-speed Railway Engineering Southwest Jiaotong UniversityChengdu610031China Guangzhou Metro Design and Research Institute Co Ltd. Guangzhou510010China Chengdu City Construction Investment Group Co Ltd. Chengdu610036China

This paper examines the effect of the microstructure and electrical conductivity(EC)on the swelling ratio and pressure in red-bed mudstone sampled from arid areas in the Xining region in the northeastern Tibetan Plateau.A series of laboratory tests,including swelling experiments,X-ray diffraction(XRD),and scanning electron microscope(SEM),was carried out for mechanical and microstructural *** coupled influence of the EC and microstructural parameters on the expansion ratio and pressure was investigated,and the weight coefficients were discussed by the entropy weight *** results revealed an increasing exponential trend in EC,and the maximum swelling speed occurred at an EC of approximately 10 μS/*** addition,a method for predicting the expansion potential is proposed based on the microstructure,and its reliability is verified by comparing with swelling experimental *** addition,according to the image analysis results,the ranges of the change in the clay minerals content(CMC),the fractal dimension(FD),the average diameter(AD)of pores,and the plane porosity(PP)are 23.75%-53%,1.08-1.17,7.53-22.45 mm,and 0.62%-1.25%,***,mudstone swelling is negatively correlated with the plane porosity,fractal dimension and average diameter and is linearly correlated with the clay mineral ***,the weight values prove that the microstructural characteristics,including FD,AD,and PP,are the main factors influencing the expansion properties of red-bed mudstones in the Xining *** on the combination of macro and micro-analyses,a quantitative analysis of the swelling process of mudstones can provide a better reference for understanding the mechanism of expansion behavior.

关键词： Mudstones Microstructure Swelling characteristics Electrical conductivity(EC) Scanning electron microscope Water-swelling

A compact X-band backward traveling-wave accelerating structure

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Nuclear Science and Techniques 2024年第5期35卷 13-29页

作者： xian-Cai lin Hao Zha Jia-Ru Shi Qiang Gao Fang-Jun Hu Qing-Zhu li Huai-Bi Chen Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China

Very high-energy electrons(VHEEs)are potential candidates for FLASH radiotherapy for deep-seated *** proposed a compact VHEE facility based on an X-band high-gradient high-power *** this study,we investigated and realized the first X-band backward traveling-wave(BTW)accelerating structure as the buncher for a VHEE facility.A method for calculating the parameters of single cell from the field distribution was introduced to simplify the design of the BTW ***-domain circuit equations were applied to calculate the transient beam parameters of the buncher in the unsteady state.A prototype of the BTW structure with a thermionic cathode-diode electron gun was designed,fabricated,and tested at high power at the Tsinghua X-band high-power test *** structure successfully operated with 5-MW microwave pulses from the pulse compressor and outputted electron bunches with an energy of 8 MeV and a pulsed current of 108 mA.

关键词： Backward traveling-wave accelerating structure Equivalent circuit model High-power test Very high-energy electron radiotherapy

Intelligent extraction of road cracks based on vehicle laser point cloud and panoramic sequence images

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Journal of Road Engineering 2024年第1期4卷 69-79页

作者： Ming Guo li Zhu Ming Huang Jie Ji xian Ren Yaxuan Wei Chutian Gao School of Geomatics and Urban Spatial Informatics Beijing University of Civil Engineering and ArchitectureBeijing 102616China Engineering Research Centre of Representative Building and Architectural Heritage Database Ministry of EducationBeijing 100044China Key Laboratory of Modern Urban Surveying and Mapping National Administration of SurveyingBeijing 102616China School of Civil and Transportation Engineering Beijing University of Civil Engineering and ArchitectureBeijing 102616China

In light of the limited efficacy of conventional methods for identifying pavement cracks and the absence of comprehensive depth and location data in two-dimensional photographs,this study presents an intelligent strategy for extracting road *** methodology involves the integration of laser point cloud data obtained from a vehicle-mounted system and a panoramic sequence of *** study employs a vehicle-mounted liDAR measurement system to acquire laser point cloud and panoramic sequence image data simultaneously.A convolutional neural network is utilized to extract cracks from the panoramic sequence *** extracted sequence image is then aligned with the laser point cloud,enabling the assignment of RGB information to the vehicle-mounted three dimensional(3D)point cloud and location information to the two dimensional(2D)panoramic ***,a threshold value is set based on the crack elevation change to extract the aligned roadway point *** three-dimensional data pertaining to the cracks can be *** experimental findings demonstrate that the use of convolutional neural networks has yielded noteworthy outcomes in the extraction of road *** utilization of point cloud and image alignment techniques enables the extraction of precise location data pertaining to road *** approach exhibits superior accuracy when compared to conventional ***,it facilitates rapid and accurate identification and localization of road cracks,thereby playing a crucial role in ensuring road maintenance and traffic ***,this technique finds extensive application in the domains of intelligent transportation and urbanization *** technology exhibits significant promise for use in the domains of intelligent transportation and city development.

关键词： Road crack extraction Vehicle laser point cloud Panoramic sequence images Convolutional neural network

Heterostructure Cu_(3)P-Ni_(2)P/CP catalyst assembled membrane electrode for high-efficiency electrocatalytic nitrate to ammonia

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Nano Research 2024年第6期17卷 4872-4881页

作者： Meng Jin Jiafang liu xian Zhang Shengbo Zhang Wenyi li Dianding Sun Yunxia Zhang Guozhong Wang Haimin Zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Anhui Contango New Energy Technology Co. Ltd.Hefei 230031China

Electrochemical nitrate reduction reaction(NO_(3)RR)is a promising means for generating the energy carrier ***,we report the synthesis of heterostructure copper-nickel phosphide electrocatalysts via a simple vapor-phase hydrothermal *** resultant catalysts were evaluated for electrocatalytic nitrate reduction to ammonia(NH_(3))in three-type electrochemical *** detail,the regulation mechanism of the heterogeneous Cu_(3)P-Ni_(2)P/CP-x for NO_(3)RR performance was systematically studied through the H-type cell,rotating disk electrode setup,and membrane-electrode-assemblies(MEA)*** a result,the Cu_(3)P-Ni_(2)P/CP-0.5 displays the practicability in an MEA system with an anion exchange membrane,affording the largest ammonia yield rate(RNH_(3))of 1.9 mmol·h^(−1)·cm^(−2),exceeding most of the electrocatalytic nitrate reduction electrocatalysts reported to *** theoretical calculations and in-situ spectroscopy characterizations uncover that the formed heterointerface in Cu_(3)P-Ni_(2)P/CP is beneficial for promoting nitrate adsorption,activation,and conversion to ammonia through the successive hydrodeoxygenation pathway.

关键词： electrocatalytic nitrate reduction to ammonia three-type reactors membrane-electrode-assemblies system operando ATR-IRRAS successive hydrodeoxygenation pathway

Metal-organic framework-derived CoSe_(2)@N-doped carbon nanocubes for high-performance lithium-ion capacitors

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Rare Metals 2024年第5期43卷 2150-2160页

作者： Lei Wang Xiong Zhang Yan-Yan Kong Chen li Ya-Bin An xian-Zhong Sun Kai Wang Yan-Wei Ma Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100190China Institute of Electrical Engineering and Advanced Electromagnetic Drive Technology Qilu ZhongkeJinan 250013China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

Cobalt selenide(CoSe_(2))has garnered considerable attention as a prospective anode candidate for advanced lithium-ion storage,prompting comprehensive ***,CoSe_(2)-based anodes usually suffer from significant volume variation upon lithiation leading to unsatisfactory cycling ***,a versatile synthesis route is proposed for the in-situ fabrication of CoSe2nanoparticles embedded in N-dope carbon skeleton(CoSe_(2)@NC)through annealing treatment and selenization of a metal–organic framework-derived(MOF)*** N-doped carbon derived from the MOF serves not only as an excellent conductive substrate but also as a confined reactor,effectively inhibiting the structural instability and alleviating the inevitable volume change of CoSe_(2).Owing to their unique nanostructure,the as-prepared CoSe_(2)@NC exhibits a high capacity of 745.9mAh·g^(-1)at 0.1 A·g^(-1),while maintaining excellent rate capability and an impressive ***,the assembled lithium-ion capacitor(liC)based on CoSe_(2)@NC demonstrates an energy density of 130Wh·kg^(-1),a power density of 24.6 kW·kg^(-1),and remarkable capacity retention of 90.8%after 8000 *** results highlight the great potential of CoSe_(2)@NC for practical applications.

关键词： lithium capacitors Cobalt selenide Metal-organic frameworks N-doped carbon

Design of weak current measurement system and research on temperature impact

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Nuclear Science and Techniques 2024年第4期35卷 46-56页

作者： Chu-xiang Zhao San-Gang li Rong-Rong Su li Yang Ming-Zhe liu Qing-Yue Xue Shan liao Zhi Zhou Qing-Shan Tan xian-Guo Tuo Yi Cheng College of Nuclear Technology and Automation Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu University of Technology1#DongsanluErxianqiaoChengdu 610059China University of Science and Technology of China Hefei 230026China School of Physics and Electronic Engineering Sichuan University of Science and EngineeringZigong 643000China

A dedicated weak current measurement system was designed to measure the weak currents generated by the neutron ionization *** system incorporates a second-order low-pass filter circuit and the Kalman filtering algorithm to effectively filter out noise and minimize interference in the measurement *** conducted under normal temperature conditions has demonstrated the system's high precision ***,it was observed that temperature variations can affect the measurement *** were collected across temperatures ranging from -20 to 70℃,and a temperature correction model was established through linear regression fitting to address this *** feasibility of the temperature correction model was confirmed at temperatures of -5 and 40℃,where relative errors remained below 0.1% after applying the temperature *** research indicates that the designed measurement system exhibits excellent temperature adaptability and high precision,making it particularly suitable for measuring weak currents.

关键词： Weak current measurement system Neutron ionization chamber Kalman filter algorithm Temperature correction model