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CSEE Journal of Power and Energy Systems 2023年第2期9卷 790-801页

作者： Yao Zhong Jian hao Xupeng Wang Ruijin Liao Ruilei Gong Yilin Ding State Key Laboratory of Power Transmission Equipment&System Security and New Technology University of ChongqingChongqing 400044China Shandong Taikai High Voltage Swichgear Co.Ltd. Taian 271000China

Mechanical defects,in gas-insulated switchgear(GIS)equipment,have weak response characteristics,leading to significant difficulties in the classification of ***,this paper proposes a novel mechanical defect feature extraction and classification method that combines independent intrinsic mode function(IIMF)analysis and an improved multikernel mapping fast multi-classification relevance vector machine(MKF-mRVM).Enlightened by the differences in the GIS operating vibration mode,the IIMF series were first obtained based on regenerated phase-shifted sinusoid-assisted empirical mode decomposition(RPSEMD)and modal *** singular value decomposition and time-frequency conversions were performed to construct combined feature ***,multikernel mapping and domain sampling were introduced to improve the calculation speed and recognition accuracy of the mRVM,which was more suitable for on-line *** show that the proposed RPSEMD-MKF-mRVM model achieves a faster training speed(14.23 s)and higher accuracy(98.21%)than other algorithms,and it can adapt to variable loads.

关键词： GIS IIMF analysis mechanical defect MKFmRVM RPSEMD

Microstructure and mechanical properties of in situ(TiC+SiC)/FeCrCoNi high entropy alloy matrix composites

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Journal of Iron and Steel Research International 2021年第4期28卷 496-504页

作者： Yu-lu Li Yue Zhao Lin Shen hao Wu He-guo Zhu College of Materials Science and Engineering Nanjing University of Science and TechnologyNanjing 210094JiangsuChina

In situ(TiC+SiC)particles(5 vol.%and 10 vol.%,respectively)-reinforced FeCrCoNi high entropy alloy matrix composites were fabricated via vacuum inductive melting method,with equal volume fractions of TiC and SiC particles.X-ray diffraction,scanning electron microscope and energy diffraction spectrum were employed to analyze the microstructure and composi-tion of the *** results manifested that the FeCrCoNi matrix is composed of FCC phase,and the in situ particles are homogeneously scattered in the *** presence of reinforcements augmented the ultimate tensile strength from 452 to 783 MPa,and raised the yield strength from 162 to 466 MPa at room temperature,whereas the elongation to fracture was reduced from 70.6%to 28.6%.All the tensile fracture surfaces consisted of numerous tiny dimples,indicating that the composites exhibited ductile ***,the enhancement of strength ascribes to a combination of thermal mis-match strengthening,load-bearing effect,grain refinement,Orowan strengthening and solid solution strengthening effect,which contribute about 58.0%,2.4%,12.3%,11.1%and 16.2%to the improvement of yield tensile strength,respectively.

关键词： High entropy alloy matrix composite In situ reaction Microstructure Mechanical property Strengthening mechanism

Nano Calcium-Deficient Hydroxyapatite/O-carboxymethyl Chitosan-CaCl_(2) Microspheres Loadedwith RheinforBone Defect Repair

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Journal of Bionic Engineering 2022年第4期19卷 1087-1099页

作者： Zhenzhen Tian Yuanyuan Guo Xiuying Yang Kebing Guo Jingou Ji Shilei hao School of Chemistry and Chemical Engineering Chongqing UniversityNo.55University City South RoadShapingba DistrictChongqing 401331China Key Laboratory of Biorheological Science and Technology Ministry of EducationCollege of BioengineeringChongqing UniversityChongqing 400030China Guizhou KingMed Center for Clinical Laboratory Co. LtdGuizhou 550001China

Glutaraldehyde(GA),the most widely used crosslinking agent for biomaterials,is ***_(2) is of particular interest due to its non-toxic *** can chelate Ca^(2+)and promote bone *** we reported a novel nano calcium-deficient hydroxyapatite/O-carboxymethyl chitosan-CaCl_(2) microspheres loaded with rhein(RH-nCDHA/OCMC-CaCl_(2) microspheres)using CaCl_(2) as crosslinking agent for bone defect *** obtained microspheres were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),thermogravimetric analysis(TG)and Fourier transform infrared spectroscopy(FT-IR).The surface of the obtained microspheres is rough with quite a few *** nano calcium-deficient hydroxyapatite(nCDHA)accounts for about 70% of the total weight of the microspheres,which is equivalent to the proportion of inorganic substances in human bones.A high encapsulation efficiency(EE)and loading capacity(LC)of the microspheres loaded with rhein was 90.20±0.60% and 11.03±0.30%,*** microspheres using CaCl_(2) in simulated body fluid(SBF)after 14 days,the drug released continuously and bone-like apatite formed like *** cells on the surface of the RH-nCDHA/OCMC-CaCl_(2) microspheres grew better comparing with nCDHA/OCMC-GA microspheres and the skull defects of rats after landfill can be almost repaired after 8 weeks,which revealed the potential of the microspheres for bone repair.

关键词： Nano calcium-deficient hydroxyapatite O-carboxymethyl chitosan Rhein Microspheres Bone repair

Evaluation method for helicopter maritime search and rescue response plan with uncertainty

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Chinese Journal of Aeronautics 2021年第4期34卷 493-507页

作者： Hu LIU Zikun CHEN Yongliang TIAN Bin WANG hao YANG Guanghui WU School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China Donghai No.2 Flying Service of Ministry of Transport Xiamen 361006China Commercial Aircraft Corporation of China Ltd Shanghai 200210China

Helicopter plays an increasingly significant role in Maritime Search and Rescue(MSAR),and it will perform MSAR mission based on response plans when an accident *** the rationality of response plan determines the success of MSAR mission to a large ***,with the impact of many uncertainty factors,it is difficult to evaluate response plans comprehensively before performing *** at these problems,an evaluation framework of helicopter MSAR response plan named UMAD is proposed in this paper,which reveals the influence mechanism of uncertainty factors based on Multi-Agent method and analyzes the mission flow based on Discrete Event System(DEVS)***,the evaluation criterion and indicators of response plan are extracted from the aspects of safety and ***,the Monte Carlo method is adapted to calculate the probability distribution and robustness of response plan comprehensive ***,in order to illustrate the validity of this method,it is discussed and verified by an application example of evaluating multiple response plans to the same MSAR *** results show that this method can analyze the influence of uncertainty more systematically and optimize response plans more comprehensively.

关键词： Evaluation method Maritime search and rescue Probability distribution Response plan Robustness Uncertainty factors

Response of water-use efficiency to phenology in the natural forest and grassland of the Loess Plateau in China

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Science China Earth Sciences 2023年第9期66卷 2081-2096页

作者： Xingyan TAN Yangwen JIA Cunwen NIU Dawen YANG Wen LU Chunfeng hao State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of Simulation and Regulation of River Basin Water Cycle(SKL-WAC) China Institute of Water Resources and Hydropower Research(IWHR)Beijing 100038China

Ecosystem water use efficiency(WUE)is an integrated physiological metric for the coupling cycle between terrestrial carbon,water,and *** WUE responds to vegetation phenology(e.g.,SOS,EOS-start,end of growing season,and GSL-growing season length)shifting in temperate semi-arid regions is a hot spot in relative research *** on remotesensing products and in-situ measured climate data,this study discussed how gross primary productivity(GPP),evapotranspiration(ET),and WUE(quantified by GPP/ET)would change with the altering vegetation phenology and climate in the untouched semi-arid forests and grasslands of the Chinese Loess Plateau during 2001–*** results show that vegetation tended to green-up earlier and brown-down later from 2001 to 2020,causing an extended *** forests had an earlier SOS,later EOS,and longer GSL than the grasslands,but the latter had a bigger variation *** WUE in the study area decreased significantly during spring and summer,while the grassland WUE increased in autumn;the annual mean reduction rate in grassland WUE was approximately twice that of *** SOS could increase forest WUE but reduce grassland WUE in spring,mainly because leaf unfolding has a more pronounced limitation on soil evaporation beneath the forest *** had less impact on WUE,and no apparent difference existed between these two *** change could affect WUE directly by changing GPP and ET and indirectly by regulating vegetation *** can increase GPP and ET,causing an earlier SOS,further promoting GPP and ET(except forest ET).Precipitation significantly affected forest GPP and ET in spring,grassland GPP and ET in summer,and grassland ET in autumn;precipitation affects spring grassland WUE mainly via regulating *** solar radiation could suppress grassland GPP in spring,promote forest ET in autumn,and regulate grassland WUE by affecting *** study is meaningful for improving the process-ba

关键词： Water use efficiency Vegetation phenology Climate change Remote sensing The Loess Plateau

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Continuous roll-to-roll patterning of three-dimensional periodic nanostructures

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Microsystems & Nanoengineering 2020年第1期6卷 1067-1077页

作者： I-Te Chen Elizabeth Schappell Xiaolong Zhang Chih-hao Chang Department of Mechanical and Aerospace Engineering North Carolina State UniversityRaleighNC 27695USA Walker Department of Mechanical Engineering University of Texas at AustinAustinTX 78712USA

In this work,we introduce a roll-to-roll system that can continuously print three-dimensional(3D)periodic nanostructures over large *** approach is based on Langmuir-Blodgett assembly of colloidal nanospheres,which diffract normal incident light to create a complex intensity pattern for near-field *** geometry of the 3D nanostructure is defined by the Talbot effect and can be precisely designed by tuning the ratio of the nanosphere diameter to the exposure *** this system,we have demonstrated patterning of 3D photonic crystals with a 500 nm period on a 50×200 mm^(2) flexible substrate,with a system throughput of 3mm/*** patterning yield is quantitatively analyzed by an automated electron beam inspection method,demonstrating long-term repeatability of an up to 88% yield over a 4-month *** inspection method can also be employed to examine pattern uniformity,achieving an average yield of up to 78.6% over full substrate *** proposed patterning method is highly versatile and scalable as a nanomanufacturing platform and can find application in nanophotonics,nanoarchitected materials,and multifunctional nanostructures.

关键词： tuning lithography periodic

Monitoring lime and cement improvement using spectral induced polarization and bender element techniques

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第1期13卷 202-211页

作者： Bate Bate Junnan Cao Chi Zhang Na hao Song Wang Institute of Geotechnical Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou310058China Department of Civil and Environmental Engineering Colorado School of MinesGoldenColombia80401USA Department of Geology University of KansasLawrenceKS66045USA Department of Civil Engineering and Construction Management Georgia Southern UniversityStatesboroGA30458USA

Spectral induced polarization(SIP)and bender element(BE)techniques show a high sensitivity to particle size,particle distribution and content of generated hydration products,which essentially govern the efficiency of ground *** this context,both SIP and BE were integrated on a column setup to monitor the processes of lime and cement stabilization.A 5 mmol/L Na2CO3 solution was injected into the sand-lime mixture to produce CaCO3 precipitation,while deionized water was injected into the sandcement mixture to induce the hydration of *** average diameters of the precipitated particles or clusters were calculated from the relaxation time,which was a significant parameter of SIP signals,via the Schwarz *** pairs of BE were used to demonstrate the heterogeneity of the product precipitation,which was probably caused by the location of the inflow and outflow on the SIP-BE *** and BE showed the capability of nondestructively monitoring the spatiotemporal chemical evolution processes,which could be helpful for engineering applications.

关键词： Particle size and distribution Spectral induced polarization(SIP) Bender element(BE) Cement hydration Complex conductivity Shear wave velocity Heterogeneity

长期秸秆还田对下茬还田秸秆的降解及土壤微生物群落的影响

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环境科学 2025年第1期46卷 532-542页

作者：周斯豪王美琦宋瑶牛宏进赵经纬侯瑞楠陈晓波黄亚丽河北科技大学环境科学与工程学院石家庄050018 河北科技大学食品与生物学院石家庄050018

探究长期秸秆还田土壤残留效应对秸秆降解及微生物群落的影响.以连续15 a秸秆还田土壤(SS)和秸秆未还田土壤(NS)为研究对象,通过模拟试验分析两种土壤同时秸秆还田后秸秆的降解情况和土壤微生物种群的变化.采用沙袋法测定秸秆降解率,稀... 详细信息

探究长期秸秆还田土壤残留效应对秸秆降解及微生物群落的影响.以连续15 a秸秆还田土壤(SS)和秸秆未还田土壤(NS)为研究对象,通过模拟试验分析两种土壤同时秸秆还田后秸秆的降解情况和土壤微生物种群的变化.采用沙袋法测定秸秆降解率,稀释涂布平板法测定土壤可培养微生物数量,高通量测序技术分析土壤微生物群落多样性和结构.结果表明,与NS相比,SS显著增加15 d和30 d秸秆降解率,增幅为14.16%和26.57%;显著增加0~60 d内土壤可培养真菌的数量,增幅为43.10%~185.92%;显著增加0 d和42 d和56 d时纤维素降解菌数量,增幅为55.12%~92.04%.秸秆还田7 d时,SS中的细菌ACE指数、真菌ACE指数和Chao1指数低于NS,说明SS土壤中微生物群落丰富度显著降低.在门水平上,SS中酸杆菌门、浮霉菌门和己科河菌门等细菌门相对丰度显著增加,增幅为25.92%~45.17%;油壶菌门、捕虫霉亚门和球囊菌门等真菌门相对丰度显著增加,增幅为12.09%~176.00%.在属水平上,SS中Subgroup6纲未定属和罗库菌目未定属等细菌属相对丰度显著增加,增幅为28.91%~31.26%;拟青霉菌属、被孢霉菌属和青霉菌属等真菌属相对丰度显著增加,增幅为2.98%~8.79%.分子生态网络分析表明,SS细菌网络互作程度更高、网络连接更紧密,真菌网络则呈现更加复杂和稳定的结构.RDA结果显示,土壤微生物群落组成与秸秆降解率呈极显著相关.SS对下茬还田秸秆的降解、土壤可培养微生物数量和种群结构变化在一定时间内表现出明显的残留效应,其微生物菌群更利于下茬还田秸秆的降解.

关键词：秸秆还田残留效应秸秆降解微生物群落网络分析

Rational Design of High-Performance Bilayer Solar Evaporator by Using Waste Polyester-Derived Porous Carbon-Coated Wood

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Energy & Environmental Materials 2022年第2期5卷 617-626页

作者： Ning Liu Liang hao Boyi Zhang Ran Niu Jiang Gong Tao Tang Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Wood-based bilayer solar evaporators,which possess cooperative advantages of natural wood and photothermal conversion coating including fast water transportation,low heat conduction,renewability,and high light absorbability,hold great promise for water ***,previous studies suffer from low evaporation rates and high cost of coatings,and lack a deep understanding how the porous structures of coating layer ***,a novel bilayer solar evaporator is designed through facile surface coating of wood by low-cost porous carbon from controlled carbonization of polyester *** porous carbon bears rich oxygen-containing groups,well-controlled micro-/meso-/macropores,and high surface areas(1164 m^(2) g^(−1)).It is proved that porous carbon improves sunlight absorption and promotes the formation of numerous water clusters to reduce water evaporation *** to these combined features,the bilayer solar evaporator exhibits high evaporation rate(2.38 kg m^(−2) h^(−1)),excellent longterm stability,and good salt *** importantly,a large-scale solar desalination device for outdoor experiments is developed to produce freshwater from *** daily freshwater production amount(3.65 kg m^(−2))per unit area meets the daily water consumption requirement of one *** findings will inspire new paradigms toward developing efficient solar steaming technologies for desalination to address global freshwater shortage.

关键词： solar steam generation waste polyester hierarchically porous carbon desalination freshwater production

Large-disturbance Stability Analysis of Power Systems with Synchronous Generator and Converter-interfaced Generation

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 997-1002页

作者： Lei Chen Yong Min Liangshuai hao Guangzheng Xing Yalou Li Shiyun Xu Department of Electrical Engineering Tsinghua UniversityBeijing 100084China China Electric Power Research Institute Beijing 100192China

This letter studies large-disturbance stability of the power system with a synchronous generator(SG)and a converter-interfaced generation(CIG)connected to infinite *** power system is multi-timescale and first *** is shown that the boundary of region of attraction(ROA)of the simplified model is composed of stable manifolds of unstable equilibrium point(UEP)or semi-singular point(SSP),named anchor points,and singular surface *** type of anchor point determines the dominant instability pattern of the power *** the anchor point is UEP or SSP,the dominant instability pattern is the instability of rotor angle of SG or the instability of phase-locked loop and outer control loop(OCL)of CIG,*** of dominant instability pattern can be analyzed with the relative position relationship between UEP and *** effect of OCL is *** the OCL is activated,the ROA becomes smaller and the system is more prone to instability of *** is necessary to consider the OCL when studying the large-disturbance stability of the power system.

关键词： Converter-interfaced generation large-disturbance stability outer control loop phase-locked loop synchronous generator voltage source converter