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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 46-56页

作者： Qiu Shiming wang shengjie School of Chemistry and Chemical Engineering Guangxi Minzu Normal UniversityChongzuo 532200GuangxiChina Guangxi Key Laboratory for High-value Utilization of Manganese Resources Chongzuo 532200GuangxiChina

The Cu/ZnO catalyst formed upon the calcination of aurichalcite has a uniform distribution of ZnO,which can delay the sintering of Cu species at high *** this study,aurichalcite possessing a nearly pure phase was prepared using the ammonium complex dissociation precipitation method,and the effect of calcination temperature on the structure and surface properties of the derived Cu/ZnO catalyst was *** results show that the calcination temperature determines the particle size and crystallization degree of the Cu/ZnO catalyst and the surface properties of the corresponding copper oxide and reduced ***-temperature calcination is more conducive to reducing the particle size of the Cu/ZnO catalyst,increasing the specific surface area,and generating abundant defect characteristics on the surface,which is key to obtaining highly dispersed copper and copper-specific surface area catalysts by subsequent ***,the Cu/ZnO catalyst derived using a 300℃or 400℃calcination proved to have a higher specific activity per gram of copper than a commercial Cu/Zn/Al *** discovery in this study opens up a new method for the convenient preparation of a high-temperature resistant Cu/Zn methanol reforming catalyst.

关键词： methanol reforming copper zinc oxide lattice defect

Effect of wear debris on fretting fatigue crack initiation

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Friction 2022年第6期10卷 927-943页

作者： shengjie wang Tongyan YUE Dagang wang Magd ABDEL WAHAB Soete Laboratory Department of Electrical EnergyMetalsMechanical Construction&SystemsFaculty of Engineering and ArchitectureGhent UniversityGhent 9052Belgium State Grid Xinyuan Maintenance Branch Beijing 100000China School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China Faculty of Engineering Van Lang UniversityHo Chi Minh City 700000Vietnam Soete Laboratory Ghent UniversityGhent 9052Belgium

Both wear and fatigue occur in fretting condition,and they interact with one another during the whole *** fatigue is commonly analysed without considering the effect of wear in partial slip regime,although wear affects the lifetime of crack *** paper investigates,for the first time,the effect of wear debris on fretting fatigue crack *** investigate the effect of debris,first fretting wear characteristics in partial slip regime are analysed for loading ***,the effect of wear on fretting fatigue crack initiation is investigated using Ruiz parameters and critical plane methods without considering the debris *** the results,we can see that loading conditions affect the wear profiles in different ***,wear has a significant effect on the fatigue in partial slip regime without considering debris especially on the crack initiation ***,considering wear debris in the analysis,its effect on critical plane parameters is *** is found that by considering the wear debris effect,the frtting fatigue crack initiation location is shifted towards the trailing *** predictions of both crack initiation location and lifetime show a good agreement with the experimental data.

关键词： fretting wear fretting fatigue critical plane Ruiz parameter debris

Dynamic response to climate change in the radial growth of Picea schrenkiana in western Tien Shan,China

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Journal of Forestry Research 2022年第1期33卷 147-157页

作者： Liang Jiao shengjie wang Ke Chen Xiaoping Liu College of Geography and Environment Science Northwest Normal UniversityLanzhou 730070People’s Republic of China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875People’s Republic of China

Forests are important ecosystems for economic and social ***,the response of tree radial growth to climate has produced‘divergent problems'at high latitudes under global *** this study,the response stability and trend of Picea schrenkiana radial growth to variability in climate factors were analyzed in the mid-latitudes of the western Tien Shan *** growth of *** was mainly limited by minimum and mean *** divergent responses of radial growth occurred in response to the minimum and mean temperatures at the beginning of the growing season(April–May)of the current year,but responses to drought occurred in July–September of the previous *** the mean and minimum temperatures in June–September of the current year were both *** growth first increased and then decreased according to the basal area increment,with a gradual increase in ***,forest ecosystems in mountainous arid areas will be increasingly affected by future climate warming.

关键词： Dendroecology Divergent response Climate change Forest degradation Western Tien Shan mountains

Multiscale Analysis of the Effect of Debris on Fretting Wear Process Using a Semi-Concurrent Method

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Computers, Materials & Continua 2020年第1期62卷 17-35页

作者： shengjie wang Tongyan Yue Magd Abdel Wahab Soete Laboratory Faculty of Engineering and ArchitectureGhent UniversityTechnologiepark Zwijnaarde 903Zwijnaarde B-9052Belgium State Grid Xinyuan Maintenance Branch BeijingChina Division of Computational Mechanics Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityVietnam

Fretting wear is a phenomenon,in which wear happens between two oscillatory moving contact surfaces in microscale *** this paper,the effect of debris between pad and specimen is analyzed by using a semi-concurrent multiscale ***,the macroscale fretting wear model is ***,the part with the wear profile is imported from the macroscale model to a microscale model after running in ***,an effective pad’s radius is extracted by analyzing the contact pressure in order to take into account the effect of the ***,the effective radius is up-scaled from the microscale model to the macroscale model,which is used after running in *** this way,the effect of debris is considered by changing the radius of the pad in the macroscale *** to the smaller number of elements in the microscale model compared with the macroscale model containing the debris layer,the semi-concurrent method proposed in this paper is more computationally ***,the results of this semi-concurrent method show a better agreement with experimental data,compared to the results of the model ignoring the effect of debris.

关键词： Fretting wear debris multiscale analysis semi-concurrent

Multiple Targets Localization Algorithm Based on Covariance Matrix Sparse Representation and Bayesian Learning

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Journal of Beijing Institute of Technology 2024年第2期33卷 119-129页

作者： Jichuan Liu Xiangzhi Meng shengjie wang School of Electronic Engineering Xidian UniversityXi’an 710071China Hebei Key Laboratory of Electromagnetic Spectrum Cognition and Control Shijiazhuang 050081China

The multi-source passive localization problem is a problem of great interest in signal pro-cessing with many *** this paper,a sparse representation model based on covariance matrix is constructed for the long-range localization scenario,and a sparse Bayesian learning algo-rithm based on Laplace prior of signal covariance is developed for the base mismatch problem caused by target deviation from the initial point *** adaptive grid sparse Bayesian learning targets localization(AGSBL)algorithm is *** AGSBL algorithm implements a covari-ance-based sparse signal reconstruction and grid adaptive localization dictionary ***-tion results show that the AGSBL algorithm outperforms the traditional compressed-aware localiza-tion algorithm for different signal-to-noise ratios and different number of targets in long-range scenes.

关键词： grid adaptive model Bayesian learning multi-source localization

Evaluating the soil evaporation loss rate in a gravel-sand mulching environment based on stable isotopes data

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Journal of Arid Land 2022年第8期14卷 925-939页

作者： YANG Ye ZHANG Mingjun ZHANG Yu wang shengjie wang Jiaxin College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Lanzhou 730070China

In order to cope with drought and water shortages,the working people in the arid areas of Northwest China have developed a drought-resistant planting method,namely,gravel-sand mulching,after long-term agricultural *** understand the effects of gravel-sand mulching on soil water evaporation,we selected Baifeng peach(Amygdalus persica L.)orchards in Northwest China as the experimental field in *** on continuously collected soil water stable isotopes data,we evaluated the soil evaporation loss rate in a gravel-sand mulching environment using the line-conditioned excess(lc-excess)coupled Rayleigh fractionation model and Craig-Gordon *** results show that the average soil water content in the plots with gravel-sand mulching is 1.86%higher than that without gravel-sand *** monthly variation of the soil water content is smaller in the plots with gravel-sand mulching than that without gravel-sand ***,the average lc-excess value in the plots without gravel-sand mulching is *** addition,the soil evaporation loss rate in the plots with gravel-sand mulching is lower than that in the plots without gravel-sand *** lc-excess value was negative for both the plots with and without gravel-sand mulching,and it has good correlation with relative humidity,average temperature,input water content,and soil water *** effect of gravel-sand mulching on soil evaporation is most prominent in *** with the evaporation data of similar environments in the literature,the lc-excess coupled Rayleigh fractionation model is *** isotopes evidence shows that gravel-sand mulching can effectively reduce soil water evaporation,which provides a theoretical basis for agricultural water management and optimization of water-saving methods in arid areas.

关键词： soil evaporation loss rate gravel-sand mulching stable isotopes line-conditioned excess coupled Rayleigh fractionation model Craig-Gordon model

Virus-like supramolecular assemblies formed by cooperation of base pairing interaction and peptidic association

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Science China Chemistry 2016年第3期59卷 310-315页

作者： Meiwen Cao Ningning wang Peng Zhou Yawei Sun Jiqian wang shengjie wang Hai Xu Centre for Bioengineering and Biotechnology State Key Laboratory of Heavy Oil ProcessingCollege of Chemical EngineeringChina University of Petroleum(East China)Qingdao266555China

A peptide nucleic acid （PNA）-peptide conjugated molecule, T＇3（AKAE）2, was designed to have both a PNA segment for oligo- nucleotide binding and an ionic self-complementary peptide sequence for self-association. T＇3（AKAE）2 could co-assemble with oligoadenines （d（A）x） to form virus-like supramolecular structures whose morphology showed dependence on the chain length and rigidity of the d（A）x molecules. Smaller nanospheres with diameters of 13.0±2.0 nm were produced in the case of d（A）6. Wormlike aggregates with lengths of 20-50 nm and diameters of 15.0±2.5 nm were found in the cases of d（A）12, d（A）ls, d（A）24 and d（A）30. And larger spherical aggregates with diameters of 18±5 nm came into presence in the cases of d（A）36 and d（A）42＋. These nanostructures were suggested to be formed under a cooperative effect of base pair recognition and peptidic association. The study provides insights into the programmed assembly of a multi-components system as well as control of the size and shade of the co-assembled structures, which is of great significance in develouing gene/drug deliverv systems.

关键词： peptide nucleic acid oligonucleotide artificial virus co-assembly supramolecular complex

Deformation-induced martensitic transformation kinetics and correlative micromechanical behavior of medium-Mn transformation-induced plasticity steel

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Journal of Materials Science & Technology 2019年第8期35卷 1779-1786页

作者： Minghe Zhang Haiyang Chen Youkang wang shengjie wang Runguang Li Shilei Li Yan-Dong wang Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology Beijing

An in situ high-energy X-ray diffraction(HE-XRD) technique was mainly used to investigate the micromechanical behavior of medium-Mn Fe-0.12 C-10.16 Mn-1.87 Al(in wt%) transformation-induced plasticit(TRIP) steel subjected to intercritical annealing at 625℃, 650℃, 675℃ and 700℃ for 1 h. As the intercritical annealing temperature increased, the volume fraction of retained austenite(RA) and ultimate tensilstress(UTS) increased, while the Lüders strain and yield stress(YS) decreased. The incremental workhardening exponent of experimental steel increased with increasing intercritical annealing temperatureThe overall trend of the transformation kinetics of the RA with respect to the true strain followed thsigmoidal shape predicted by the Olson and Cohen(OC) model. Load partitioning occurred among the ferrite, austenite and martensite immediately after entering the yielding stage. Because the stability of thRA decreased with increasing intercritical annealing temperature, the load undertaken by the martensitincreased. The moderate transformation kinetics of the RA and effective load partitioning among constituent phases were found to contribute to a favorable combination of strength and ductility for thimedium-Mn TRIP steel.

关键词： Medium-Mn TRIP steel High-energy X-ray diffraction Transformation kinetics Load partitioning

Dynamic train dwell time forecasting:a hybrid approach to address the influence of passenger flow fluctuations

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Railway Engineering Science 2023年第4期31卷 351-369页

作者： Zishuai Pang Liwen wang shengjie wang Li Li Qiyuan Peng School of Transportation and Logistics Southwest Jiaotong UniversityChengdu 610031China National Engineering Laboratory of Integrated Transportation Big Data Application Technology Southwest Jiaotong UniversityChengdu 610031China

Train timetables and operations are defined by the train running time in sections,dwell time at stations,and headways between *** estimation of these factors is essential to decision-making for train delay reduction,train dispatching,and station capacity *** the present study,we aim to propose a train dwell time model based on an averaging mechanism and dynamic updating to address the challenges in the train dwell time prediction problem(e.g.,dynamics over time,heavy-tailed distribution of data,and spatiotemporal relationships of factors)for real-time train *** averaging mechanism in the present study is based on multiple state-of-the-art base predictors,enabling the proposed model to integrate the advantages of the base predictors in addressing the challenges in terms of data attributes and data ***,considering the influence of passenger flow on train dwell time,we use a dynamic updating method based on exponential smoothing to improve the performance of the proposed method by considering the real-time passenger amount fluctuations(e.g.,passenger soars in peak hours or passenger plunges during regular periods).We conduct experiments with the train operation data and passenger flow data from the Chinese high-speed railway *** results show that due to the advantages over the base predictors,the averaging mechanism can more accurately predict the dwell time at stations than its counterparts for different prediction horizons regarding predictive errors and ***,the experimental results show that dynamic smoothing can significantly improve the accuracy of the proposed model during passenger amount changes,i.e.,15.4%and 15.5%corresponding to the mean absolute error and root mean square error,*** on the proposed predictor,a feature importance analysis shows that the planned dwell time and arrival delay are the two most important factors to dwell ***,planned time has positive influen

关键词： Train operations Dwell time Passenger flow Averaging mechanism Dynamic smoothing

Sedimentary sequence and environmental evolution in theeastern south Yellow Sea during the last deglaciation and the holocene

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Chinese Science Bulletin 1998年第9期43卷 757-761页

作者： Shaoquan Li Jian Liu shengjie wang Zigeng Yang Minist Geol & Mineral Resources Inst Marine Geol Qingdao 266071 Peoples R China

Northwest of Cheju Island in the eastern South Yellow Sea there is an arc patch of muddy deposit which coincides with an anticlokwise eddy and thus is referred to as muddy deposit of eddy. Two drilling wells, the YSDP 102 well and the YSDP 103 well, penetrated the muddy deposit and revelated the sedimentary sequence in the sea area during the last deglaciation and the Holocene. Based on shallow seismic profiles, sedimentary features and dating data, stratigraphic units formed in the eastern South Yellow Sea, documents the path, time and process of the earliest post-glacial transgression in the South Yellow Sea are presented, the formation of the Yellow Sea warm current and its control over the Yellow Sea sedimentation are discussed, and deals with the source of the muddy deposit is dealt with.

关键词： South Yellow Sea sedimentary sequence deposit of eddy environmental evolution