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Copper Tetrahydrosalen Complex Encapsulated in Zeolite Y:an Effective Heterogeneous Catalyst for the Oxidation of Cycloalkanes

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Chinese Chemical Letters 2006年第3期17卷 419-422页

作者： chun jin yin Juan JIA Bin Bin FAN jing Hong MA Rui Feng LI Key Laboratory of Coal Science and Technology MOE Institute of Special Chemicals Taiyuan University of Technology Talyuan 030024

A new heterogeneous catalyst, copper tetrahydrosalen complex encapsulated in zeolite Y （denoted as Cu[H4]salen/Y） has been developed with flexible ligand method, and characterized by FTIR, DR UV-Vis spectroscopy, N2 adsorption/desorption at -196℃. This catalyst behaved like a bio-mimic enzyme, and exhibited much higher activity for the oxidation of cycloalkanes than Cusalen/Y prepared with the same method. The effects of the reaction conditions on the catalytic performance were investigated.

关键词： Copper tetrahydrosalen complex zeolite Y encapsulation cyclohexane oxidation.

Comprehensive modeling strategy for thermomechanical tribological behavior analysis of railway vehicle disc brake system

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Friction 2024年第1期12卷 74-94页

作者： Jiabao yin chun LU Jiliang MO School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China Technology and Equipment of Rail Transit Operation and Maintenance Key Laboratory of Sichuan Province Chengdu 610031China

A comprehensive modeling strategy for studying the thermomechanical tribological behaviors is proposed in this *** wear degradation considering the influence of temperature(T)is predicted by Archard wear model with the help of the UMESHMOTION subroutine and arbitrary Lagrangian–Eulerian(ALE)remeshing *** the proposed method,the thermomechanical tribological behaviors of railway vehicle disc brake system composed of forged steel brake disc and Cu-based powder metallurgy(PM)friction block are studied *** effectiveness of the proposed methodology is validated by experimental test on a self-designed scaled brake test bench from the perspectives of interface temperature,wear degradation,friction noise and vibration,and contact status *** work can provide an effective way for the investigation of thermomechanical tribological behaviors in the engineering field.

关键词： tribological behaviors thermomechanical field wear prediction finite element simulation disc brake system railway vehicle

Pb induced dislocation defects of PtCo systems: Strain-triggered oxygen reduction reaction for PEMFC

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Nano Research 2024年第4期17卷 2462-2472页

作者： chun jin Qiheng Wang jingjun Liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

Design and development of advanced electrocatalysts with high performance and low Pt consumption are crucial for reducing the kinetic energy barrier of the cathode oxygen reduction reaction(ORR)and improving the efficiency of proton exchange membrane fuel cells(PEMFC).In this study,we demonstrate a Pb-modulated PtCo system for efficient ORR,in which the inclusion of Pb in ternary alloys induces dislocation defects due to the significant difference in atomic ***-PtCoPb was confirmed to exhibit significantly higher ORR activity and stability in acidic *** practical PEMFC applications,it outperforms the corresponding commercial Pt/C with a mass activity of 0.58 A·mgPt^(-1),making it a promising alternative to state-of-the-art Pt-based *** combination of experimental results and density functional theory(DFT)calculations offers valuable atomic-level insights into the dislocation *** with a larger atomic radius is located in the lattice stretching region below the dislocation slip plane,forming a structure similar to a Cottrell atmosphere,which reduces the dislocation energy and puts the system in a lower energy *** Cottrell atmosphere pins the dislocation structure and stabilizes the ternary *** adjusting the amount of added Pb,a moderate level of dislocation density induces a tuned strain effect,thereby enhancing the electrocatalytic mechanism by optimizing the electronic structure of the alloy surface and the adsorption and desorption of oxygen *** work provides valuable insights into the design and development of lattice dislocation defect structures to trigger strain effects for improving ORR performance.

关键词： dislocation defect strain effect Pb-modulated oxygen reduction reaction

Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity

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Chinese Geographical Science 2024年第3期34卷 453-467页

作者： HUANG Xiaoyan KANG Chenchen yin chun TANG Junqing Northwest Land and Resources Research Center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi’an 710119China School of Resource and Environmental Sciences Wuhan UniversityWuhan 430079China International Institute of Spatial Lifecourse Health(ISLE) Wuhan UniversityWuhan 430079China School of Urban Planning and Design Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China Key Laboratory of Earth Surface System and Human-Earth Relations of Ministry of Natural Resources of China Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China

Transportation accessibility has been treated as an important means of reducing the urban-rural income ***,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial *** on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial *** result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle *** urban-rural income disparity exhibits strong spatial clustering *** highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect ***,there is a substitution effect between highway accessibility and railway accessibility in the whole ***,these associations differ in geographic *** the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway *** the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway *** conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial *** and railways should be developed in a coordinated manner to promote an integrated transport network system.

关键词： transport accessibility income gap regional divergence spatial heterogeneity urban and rural areas China

Dynamic Scene Graph Generation of Point Clouds with Structural Representation Learning

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Tsinghua Science and Technology 2024年第1期29卷 232-243页

作者： Chao Qi Jianqin yin Zhicheng Zhang jin Tang School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 100876China Standard and Metrology Research Institute China Academy of Railway Sciences Corporation LimitedBeijing 100081China

Scene graphs of point clouds help to understand object-level relationships in the 3D *** graph generation methods work on 2D structured data,which cannot be used for the 3D unstructured point cloud *** point-cloud-based methods generate the scene graph with an additional graph structure that needs labor-intensive manual *** address these problems,we explore a method to convert the point clouds into structured data and generate graphs without given ***,we cluster points with similar augmented features into groups and establish their relationships,resulting in an initial structural representation of the point ***,we propose a Dynamic Graph Generation Network(DGGN)to judge the semantic labels of targets of different *** dynamically splits and merges point groups,resulting in a scene graph with high *** show that our methods outperform other baseline *** output reliable graphs describing the object-level relationships without additional manual labeled data.

关键词： scene graph generation structural representation point cloud

Coupling Analysis of Multiple Machine Learning Models for Human Activity Recognition

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Computers, Materials & Continua 2024年第6期79卷 3783-3803页

作者： Yi-chun Lai Shu-yin Chiang Yao-Chiang Kan Hsueh-chun Lin Department of Public Health China Medical UniversityTaichung406040Taiwan Department of Information and Telecommunications Engineering Ming Chuan UniversityGui-ShanTaoyuan333Taiwan Department of Electrical Engineering Yuan Ze UniversityChung-Li32003Taiwan Department and Institute of Health Service Administrations China Medical UniversityTaichung406040Taiwan

Artificial intelligence(AI)technology has become integral in the realm of medicine and healthcare,particularly in human activity recognition(HAR)applications such as fitness and rehabilitation *** study introduces a robust coupling analysis framework that integrates four AI-enabled models,combining both machine learning(ML)and deep learning(DL)approaches to evaluate their effectiveness in *** analytical dataset comprises 561 features sourced from the UCI-HAR database,forming the foundation for training the ***,the MHEALTH database is employed to replicate the modeling process for comparative purposes,while inclusion of the WISDM database,renowned for its challenging features,supports the framework’s resilience and *** ML-based models employ the methodologies including adaptive neuro-fuzzy inference system(ANFIS),support vector machine(SVM),and random forest(RF),for data *** contrast,a DL-based model utilizes one-dimensional convolution neural network(1dCNN)to automate feature ***,the recursive feature elimination(RFE)algorithm,which drives an ML-based estimator to eliminate low-participation features,helps identify the optimal features for enhancing model *** best accuracies of the ANFIS,SVM,RF,and 1dCNN models with meticulous featuring process achieve around 90%,96%,91%,and 93%,*** analysis using the MHEALTH dataset showcases the 1dCNN model’s remarkable perfect accuracy(100%),while the RF,SVM,and ANFIS models equipped with selected features achieve accuracies of 99.8%,99.7%,and 96.5%,***,when applied to the WISDM dataset,the DL-based and ML-based models attain accuracies of 91.4%and 87.3%,respectively,aligning with prior research *** conclusion,the proposed framework yields HAR models with commendable performance metrics,exhibiting its suitability for integration into the healthcare services system through AI-driven applications.

关键词： Human activity recognition artificial intelligence support vector machine random forest adaptive neuro-fuzzy inference system convolution neural network recursive feature elimination

Aggressive fibromatosis of the sigmoid colon:A case report

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3716-3722页

作者： Pan-Pan Yu Xin-chun Liu Lu yin Guang yin Department of Gastrointestinal and Anal Surgery The Affiliated Hangzhou First People's HospitalSchool of MedicineWestlake UniversityHangzhou 310006Zhejiang ProvinceChina Department of Gastric Surgery Zhejiang Cancer HospitalHangzhou 310022Zhejiang ProvinceChina Department of Pathology The Affiliated Hangzhou First People's HospitalSchool of MedicineWestlake UniversityHangzhou 310006Zhejiang ProvinceChina

BACKGROUND Aggressive fibromatosis(AF),also known as desmoid tumor or desmoid-type fibromatosis,is a rare soft tissue neoplasm that can occur in almost any part of the *** it is a benign disease,AF is aggressive and infiltrative and has a high recurrence rate after *** sites for intra-abdominal AF are the small bowel mesentery,retroperitoneum,and *** in the colon is extremely *** SUMMARY Here,we report the first case of sigmoid colon AF,which was accidentally discovered in a 27-year-old woman during laparoscopic *** tomography confirmed a slightly enhanced mass in the sigmoid *** colonoscopy did not reveal a mass in the colonic lumen,but a suspected external compress was found in the sigmoid *** disease involving a gastrointestinal stromal tumor was *** patient underwent laparoscopic exploration,and sigmoidectomy with a negative margin was performed to excise the *** immunohistochemistry revealed that the mass was an *** patient recovered well and was recurrence-free at the 30-month follow-up without adjuvant *** AF should be considered in the differential diagnosis of subepithelial colon *** resection alone can achieve good outcomes.

关键词： Aggressive fibromatosis Desmoid tumor Sigmoid mass Subepithelial tumor Case report

Proteomics Study of Benzene Metabolite Hydroquinone Induced Hematotoxicity in K562 Cells

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Biomedical and Environmental Sciences 2024年第4期37卷 341-353页

作者： jin Yi Shan YI Zong chun ZHANG Yu jing RONG Long YU chun Hong School of Biological Science and Medical Engineering Beihang UniversityBeijing 100191China School of Engineering Medicine Beihang UniversityBeijing 100191China

Objective Hydroquinone(HQ),one of the phenolic metabolites of benzene,is widely recognized as an important participant in benzene-induced ***,there are few relevant proteomics in HQ-induced hematotoxicity and the mechanism hasn’t been fully understood *** In this study,we treated K562 cells with 40μmol/L HQ for 72 h,examined and validated protein expression changes by Label-free proteomic analysis and Parallel reaction monitoring(PRM),and performed bioinformatics analysis to identify interaction *** One hundred and eighty-seven upregulated differentially expressed proteins(DEPs)and 279 downregulated DEPs were identified in HQ-exposed K562 cells,which were involved in neutrophilmediated immunity,blood microparticle,and other GO terms,as well as the lysosome,metabolic,cell cycle,and cellular senescence-related *** on the 23 DEGs and 5 DEPs in erythroid differentiation-related pathways,we constructed the network of protein interactions and determined 6 DEPs(STAT1,STAT3,CASP3,KIT,STAT5B,and VEGFA)as main hub proteins with the most interactions,among which STATs made a central impact and may be potential biomarkers of HQ-induced *** Our work reinforced the use of proteomics and bioinformatic approaches to advance knowledge on molecular mechanisms of HQ-induced hematotoxicity at the protein level and provide a valuable basis for further clarification.

关键词： Hydroquinone Proteomics Hematotoxicity K562 cells

Single-pilot operations in commercial flight:Effects on neural activity and visual behaviour under abnormalities and emergencies

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Chinese Journal of Aeronautics 2024年第8期37卷 277-292页

作者： Qinbiao LI chun-Hsien CHEN Kam K.H.NG Xin YUAN Cho yin YIU Human Factors and Ergonomics Laboratory Department of Aeronautical and Aviation EngineeringThe Hong Kong Polytechnic UniversityHong Kong Special Administrative Region 100872China School of Mechanical&Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore

With cutting-edge technologies and considering airline human-resource-saving,a single pilot in commercial jets could be technically *** changes in captains’natural behaviours are initially required to comprehend the specific safe human performance envelope for safeguarding single-pilot flight,particularly in high-risk *** paper investigates how captains’performance transforms for fixing emergencies when operating from Dual-Pilot Operations(DPO)to Single-Pilot Operations(SPO)through a physiological-based *** pilots flew an emergency-included flight with/without first officers’*** neural activities and scanning behaviours were recorded using a 32-channel Electroencephalogram(EEG)and glasses-based eye tracker,with the observation and post-experiment questionnaires to evaluate the flight operations and pilots’*** alone,there was a significantly increased cortical activity in h and b waves over the frontal,parietal,and temporal lobes during the more complicated emergencies,and pilots focused less on the primary flight display while spending significantly more time scanning the other *** physiological fluctuating patterns associated with risky operations in SPO were highlighted by cross-correlating multimodal *** experimental-based noteworthy insights may wish to inform commercial SPO measures to lessen the persistent physiological fluctuation,assisting airlines in creating SPO-oriented intelligent flight systems to give captains adequate support for assuring safer air transportation.

关键词： Aviation engineering Single pilot operations Behaviour changes Eye tracker Electroencephalogram