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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 695-706页

作者： Peiyuan Sun Long Huo Xin Chen Siyuan Liang the School of Electrical engineering Xi’an Jiaotong UniversityXi’an 710049China the School of Electrical engineering and the Center of Nanomaterials for Renewable EnergyState Key Laboratory of Electrical Insulation and Power EquipmentXi’an Jiaotong UniversityXi’an 710049China the department of Computer Science and engineering The Chinese University of Hong KongShatin999077Hong KongChina

Rotor angle stability(RAS)prediction is critically essential for maintaining normal operation of the interconnected synchronous machines in power *** wide deployment of phasor measurement units(PMUs)promotes the development of data-driven methods for RAS *** paper proposes a temporal and topological embedding deep neural network(TTEDNN)model to accurately and efficiently predict RAS by extracting the temporal and topological features from the PMU *** grid-informed adjacency matrix incorporates the structural and electrical parameter information of the power *** the small-signal RAS with disturbance under initial operating conditions and the transient RAS with short circuits on transmission lines are *** studies of the IEEE 39-bus and IEEE 300-bus power systems are used to test the performance,scalability,and robustness against measurement uncertainties of the TTEDNN *** show that the TTEDNN model performs best among existing deep learning ***,the superior transfer learning ability from small-signal RAS conditions to transient RAS conditions has been proved.

关键词： Rotor angle stability prediction topological embedding deep learning graph convolution network

Application of the CatBoost Model for Stirred Reactor State Monitoring Based on Vibration Signals

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Computer Modeling in engineering & Sciences 2024年第7期140卷 647-663页

作者： Xukai Ren Huanwei Yu Xianfeng Chen Yantong Tang Guobiao Wang Xiyong Du School of Mechanical engineering Tianjin UniversityTianjin300354China Quality department Shaoxing Key Laboratory of Special Equipment Intelligent Testing and EvaluationShaoxing312071China

Stirred reactors are key equipment in production,and unpredictable failures will result in significant economic losses and safety ***,it is necessary to monitor its health *** achieve this goal,in this study,five states of the stirred reactor were firstly preset:normal,shaft bending,blade eccentricity,bearing wear,and bolt *** signals along x,y and z axes were collected and analyzed in both the time domain and frequency ***,93 statistical features were extracted and evaluated by ReliefF,Maximal Information Coefficient(MIC)and *** above evaluation results were then fused by D-S evidence theory to extract the final 16 features that are most relevant to the state of the stirred ***,the CatBoost algorithm was introduced to establish the stirred reactor health monitoring *** validation results showed that the model achieves 100%accuracy in detecting the fault/normal state of the stirred reactor and 98%accuracy in diagnosing the type of fault.

关键词： Stirred reactor fault diagnosis vibration signal CatBoost

Insight into the mechanism of 5-hydroxymethylfurfural electroreduction to 2,5-bis(hydroxymethyl)furan over Cu anchored N-doped carbon nanosheets

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Nano Research 2024年第9期17卷 7991-7999页

作者： Haoran Wu Xinwei Chen Haishan Xu Runlu Yang Xin Wang Junying Chen Zhenbing Xie Liang Wu Yiyong Mai School of Chemical engineering Zhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgeingShanghai Jiao Tong UniversityShanghai 200240China department of Chemistry Tangshan Normal UniversityTangshan 063000China

Design of non-noble metal electrocatalysts for biomass conversion to high-value chemicals and understanding the related catalytic mechanisms are of profound significance but have remained a major ***,we developed a novel biomass-derived electrocatalyst(denoted as Cu/NC),featuring with electron-deficient copper nanoparticles anchored on N-doped carbon nanosheets,for the electrochemical reduction of 5-hydroxymethylfurfural(HMF)to 2,5-bis(hydroxymethyl)furan(BHMF,a vital precursor of functional polymers).The optimized Cu/NC electrocatalyst exhibited an excellent performance with high Faradaic efficiency(89.5%)and selectivity(90.8%)of BHMF at a low concentration of HMF(18.1 mM).Even at a very high HMF concentration(108.6 mM),the Faraday efficiency and selectivity of BHMF could still reach 74.8%and 81.1%,*** performance approached those of the reported noble metal-based *** study revealed that the N doping in the Cu/NC catalyst could regulate the electronic structure of Cu,strengthening the adsorption of the HMF carbonyl group,and thus boosting the selectivity of ***,strong electronic metal-support interactions of Cu and the N-doped carbon support optimized the charge transfer rate,thus promoting the dissociation of water to the active hydrogen(H^(*))species and boosting the reaction kinetic rate of H^(*)and HMF.

关键词： biomass 5-hydroxymethylfurfural electrochemical reduction N-doped carbon materials 2,5-bis(hydroxymethyl)furan

Extrusion-base d 3D-printe d“rolle d-up”composite scaffolds with hierarchical pore structure for bone growth and repair

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Journal of Materials Science & Technology 2024年第4期171卷 222-234页

作者： Yufan Li Li Chen Yijing Stehle Mingyue Lin Chenxin Wang Rui Zhang Min Huang Yubao Li Qin Zou Research Center for Nano Biomaterials Analytical&Testing CenterSichuan UniversityChengdu 610064China Analytical&testing Center Sichuan UniversityChengdu 610064China department of mechanical engineering Union College807 Union St.SchenectadyNY 12308USA Sichuan Institute of Atomic Energy Chengdu 610101China

Three-dimensional(3D)bioprinting,specifically direct ink writing(DIW)capable of printing biologically active substances such as growth factors or drugs under low-temperature conditions,is an emerging di-rection in bone tissue ***,limited by the bio-ink mobility and the poor resolution of this printing technology,the lateral pores of current crisscross-stacked scaffolds printed through DIW tend to clog and are inimical to bone ***,it is critical to develop DIW printed biologi-cal scaffold structure with high mechanical strength,porosity,and biocompatibility ***,patterned polylactic acid(PLA)/polycaprolactone(PCL)/nano-hydroxyapatite(n-HA)based scaffold was printed through DIW technological and rolled-up for properties characterization,cytocompatibility test,and bone repair *** result not only shows that the hexagonal patterned scaffolds are me-chanically strong with porosity,but also demonstrated that the hierarchical pore structure formed during rolled-up has the potential to address the clogging problem and stimulates bone growth and repair.

关键词： Direct ink writing(DIW) Bone repair scaffold,Micro-CT Bio composites

Dual-Porosity Apparent Permeability Models of Unconventional Gas Migration Based on Biot’s Porous Media

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Acta Mechanica Solida Sinica 2024年第3期37卷 406-415页

作者： Bin Gu Hongyuan Liu Yiuwing Mai Bing Wang School of Manufacturing Science and engineering Key Laboratory of Testing for Manufacturing ProcessMinistry of EducationSouthwest University of Science and TechnologyMianyang621010China School of Aerospace Mechanical and Mechatronic EngineeringThe University of SydneySydneyNSW2006Australia department of Mechanical engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Stress-dependent permeability models are developed for the organic pores and inorganic cleats/fractures in unconventional gas reservoirs,which are modeled as Biot’s porous media of *** considering multiple flow mechanisms such as dynamic effects of gas flow and surface diffusion,apparent permeability models are obtained to investigate the characteristics of unconventional gas *** to the gas transfer in single-porosity reservoirs,the gas migration ability of cleats in dual-porosity stratums rarely changes while that of organic pores is greatly improved because cleats sustain major geomechanical shrinkage deformation when the pore pressure ***,the mass flux of reservoirs is dominated by the mass flux of cleats,which has a lower peak value,but a much longer production term than those in single-porosity reservoirs due to the interaction between organic pores and *** analysis is conducted to identify key factors significantly impacting mass flux in unconventional *** for the mass flux variation are also explored in terms of gas migration ability and pore pressure distribution.

关键词： Unconventional gas migration Apparent permeability Dual-porosity Stress dependence Multiple flow mechanisms

The preparation and performance analysis of zirconium-modified aluminum phosphate-based high-temperature(RT-1500℃)resistant adhesive for joining alumina in extreme environment

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Journal of Advanced Ceramics 2024年第7期13卷 911-932页

作者： Jingxuan Liu Yange Wan Bo Xiao Jiancun Li Zhanming Hu Ruoyu Zhang Xiaoxia Hu Jiachen Liu Guoshuai Cai Hongli Liu Mingchao Wang College of Science Civil Aviation University of ChinaTianjin 300300China department of Safety engineering Civil Aviation University of ChinaTianjin 300300China Binzhou Beicheng Construction engineering Materials testing Co. Ltd.Binzhou 256602China department of Aviation engineering Civil Aviation University of ChinaTianjin 300300China School of Materials and engineering Key Lab of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China

High-temperature-resistant adhesives are critical materials in the aerospace *** zirconium-modified aluminum phosphate-based adhesives developed in this work had the advantage of adjustable thermal expansibility,achieving a high matching of coefficient of thermal expansion(CTE)with *** introduction of zirconium can significantly improve the thermal stability of the adhesive matrix,and the Zr/Al ratio substantially affects the various reaction processes inside the adhesive,especially the types of zirconium-containing *** of the zirconium-containing compounds in the A7Z3 adhesive were ZrO2 only when the mass ratio of zirconium hydroxide to aluminum hydroxide was 3:7,which was the key reason why it had the highest *** room-temperature bonding strength of A7Z3 after heat treatment at 1500℃reached 67.2 *** pretreatment at 1500℃,the high-temperature bonding strength of A7Z3 was greater than 50 MPa in the range of(room temperature)RT-1000℃.After 40 thermal cycles between RT and 1500℃,the bonding strength still reached 10 *** bonding occurred at temperatures below 1000℃,while chemical bonding dominated above 1000℃based on the generation of Al5BO9 and mullite at the interfaces.

关键词： high-temperature-resistant adhesive thermal expansion property zirconium-modified aluminum phosphate bonding performance thermal cycling bonding mechanism

Study on impedance spectroscopy based on dynamic equivalent circuit of solar cell

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Optoelectronics Letters 2024年第8期20卷 449-453页

作者： XIAO Wenbo LI Ao WU Huaming LI Yongbo XIAo Bangzhi Key Laboratory of Nondestructive testing Ministry of EducationNanchang Hangkong UniversityNanchang 330063China Jiangxi engineering Laboratory for Optoelectronics testing Technology Nanchang 330063China College of Science and Technology Nanchang Hangkong UniversityGongqingcheng 332020China School of engineering and Construction Nanchang UniversityNanchang 330031China

This paper investigates the impedance spectroscopy of monocrystalline silicon solar cells(MSSC)and dye-sensitized solar cells(DSSC)using solar cell dynamic equivalent resistor-capacitance(RC)and capacitor sum capacitor(CSC)***,these circuits effectively represent the dynamic behavior of MSSC and ***,the measurement method significantly impacts the accuracy of impedance measurements in the high-frequency ***,the series resistance affects the distance between the left end of the impedance spectroscopy and the origin,while the parallel resistance influences the size of the impedance *** the CSC circuit,the relative magnitudes of dielectric relaxation capacitance and chemical capacitance affect the number and position of arc in the impedance *** value of the dielectric relaxation capacitor determines the number of impedance spectroscopy *** conclusions provide guidelines for improving the accuracy of solar cell impedance measurements.

关键词： spectroscopy impedance capacitance

Weak interaction-steered evolution of polyoxovanadate-based metal-organic polyhedra from transformation via interlock to packing

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Chinese Chemical Letters 2024年第2期35卷 527-533页

作者： Yan-Hu Wang Ke-Wei Tong Chao-Qin Chen Jing Du Peng Yang College of Chemistry and Chemical engineering Advanced Catalytic Engineering Research Center of the Ministry of EducationHunan UniversityChangsha 410082China College of Chemistry and Materials Science Testing and Analysis CenterHebei Normal UniversityShijiazhuang 050024China

A bottleneck in biomimetic synthesis consists in the full copy of,for example,the hierarchical structure of proteins directed by weak *** contrast with covalent bonds bearing definite orientation and high stability,weak intermolecular forces within a continuous dynamic equilibrium can be hardly tamed for molecular *** this endeavor,a ligand-dominated strategy that embodies tunable electrostatic repulsion andπ···πstacking was first employed to shape polyoxovanadate-based metal-organic polyhedra(VMOPs).Structural evolution involving transformation,interlock,and discovery of an unprecedented prototype of the Star of David was hence *** only as a handy tool for the primary structural control over VMOPs,these weak forces allow for an advanced management on the spatial distribution of such manmade macromolecules as well as the associated physicochemical behaviors,representing an ideal model for simulating and interpreting the conformation-function relationship of proteins.

关键词： Polyoxometalates Polyoxovanadates Metal-organic polyhedron Interlock Weak intermolecular forces

Sequential alkaline-organic acid leaching process to enhance the recovery of rare earth elements from Indonesian coal fly ash

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Journal of Rare Earths 2024年第7期42卷 1366-1374,I0006页

作者： Widya Rosita Indra Perdana I Made Bendiyasa Ferian Anggara Himawan Tri Bayu Murti Petrus Agus Prasetya Isyatun Rodliyah department of Nuclear engineering and engineering Physics Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia department of Chemical engineering Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia department of Geological engineering Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Unconventional Geo-resources Research Group Faculty of EngineeringUniversitas Gadjah MadaJl Grafika No.2Yogyakarta55281Indonesia Center for testing of Mineral and Coal Tekmira-Directorate General of Mineral and Coal-Ministry of Energy and Mineral Resources Jl.Jend.Sudirman No.623Wr.MuncangKec.Bandung KulonKota BandungJawa Barat40211Indonesia

In this decade,coal fly ash(CFA)is considered a potential secondary source of rare earth elements(REEs).However,most REEs in coal fly ash are encapsulated in aluminosilicate glass,making it challenging to recover them through acid *** this study,a sequential alkaline-organic acid leaching was developed for the recovery of REEs from *** effect of alkaline leaching using NaOH solution on the destructive ability of aluminosilicate glass,as well as the mineralogy and morphology changes of the resulting coal fly ash,was first ***,the effectiveness of alkaline leaching on the recovery ability of REEs through organic acid leaching was *** results show that the maximum leaching efficiency for Si and Al,which was obtained at the optimum alkaline leaching conditions,namely NaOH concentration of 10 mol/L,reaction temperature of 65℃,liquid/solid(L/S)ratio of 10 mL/g,and reaction time of 90 min,is 28%and 32%,*** digestion reaction with NaOH lixiviants also causes coal fly ash to become more porous,making it advantageous in the organic acid-leaching process at the REEs recovery *** utilization of the desilicated residue produced from the digestion process in acid leaching effectively increases the overall REEs recovery from 32.2%to 77.6%.

关键词： Rare earth elements Alkaline Organic acid Coal fly ash

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Statistical analysis and interpretation on lightning impulse breakdown voltages of ester liquids under varying field uniformity

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High Voltage 2024年第1期9卷 22-34页

作者： Haichuan Yu Qiang Liu Zhongdong Wang department of Electrical and Electronic engineering The University of ManchesterManchesterUK department of engineering University of ExeterExeterUK

Ester liquids(ELs),as the alternative transformer liquids to the conventional mineral oils(MOs),have been increasingly used in power transformers with high voltage *** various properties,the lightning impulse breakdown voltages(LIBDVs)have been studied elaborately in the past two decades under different electric field *** electric field uniformities do have an effect on the breakdown characteristics,for example,breakdown mechanisms,polarity effects,and differences of LIBDV between ELs and MOs,which is quantitatively investigated based on the LIBDVs collected from the *** breakdown mechanism transition phenomenon between streamer initiation dominated breakdown and streamer propagation dominated breakdown has been reviewed ***,the transition field factor boundaries to observe the polarity effect on LIBDVs are taken at around 20 for ELs and 10 for ***,the transition field factor boundaries to observe the LIBDV distinctions between ELs and MOs are about 109 and 14 under positive and negative lightning impulse,*** systematic analysis and interpretation on the transition field factor boundaries among different phenomena can provide insights on insulation design of ELs filled power transformers.

关键词： field lightning breakdown