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Overview of the Importance of Intelligent Approaches on Machinery Faults Diagnosis and Prediction Based on Prognostic and Health Management/co.dition-Based Maintenance

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Journal of Donghua University(English Edition) 2018年第3期35卷 270-273页

作者： OMIDI Ali LIU Shujie School of Mechanical Engineering Dalian University of TechnologyDalian 116024China

co.dition monitoring is increasingly used to anticipate and detect failures of industrial *** of machines can cause high maintenance or replacement *** neglected,it may result in catastrophic accidents leading to production *** potential failure would negatively affect the profitability of the co.pany,including production shut down,co.t of spare parts,co.t of labor,damage of reputation,risk of injury to people and the *** recent years,co.dition-based maintenance( CBM) and prognostic and health management( PHM) are developed and formed a strong co.nection among science,engineering,computer,reliability,co.munication,management,*** maintenance management systems( CMMS) store a lot of data regarding the fault diagnosis and life prediction of the machinery ***'s too necessary to unco.er useful knowledge from the huge amount of ***'s vital to find the ways to obtain useful and co.cise information from these *** information can be of great influence in the decision making of *** article is a review of intelligent approaches in machinery faults diagnosis and prediction based on PHM and CBM.

关键词： co.dition-based maintenance(CBM) prognostic and health management(PHM) machinery fault diagnosis data mining data processing

Global co.sistency check of AIRS and IASI total co. co.umn co.centrations using WDCGG ground-based measurements

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Frontiers of Earth Science 2017年第1期11卷 1-10页

作者： Anyuan DIAO Jiong SHU Ci SONG Wei GAO Key Laboratory of Geographic Information Science (Ministry of Education) School of Geographic Sciences East China Normal University Shanghai 200241 China co.orado State University Department of Ecosystem Science and Sustainability Fort Collins Colorado 80523 USA co.orado State University Natural Resource Ecology Laboratory Fort Collins Colorado 80523 USA

This article describes a global co.sistency check of co. satellite retrieval products from the Atmospheric Infrared Sounder （AIRS） and Infrared Atmospheric Sounding Interferometer （IASI） using statistical analysis and data from the World Data Centre for Greenhouse Gases （WDCGG）. We use the co.relation co.fficient （r）, relative difference （RD）, root mean square errors （RMSE）, and mean bias error （MBE） as evaluation indicators for this study. Statistical results show that a linear positive co.relation between AIRS/IASI and WDCGG data occurs for most regions around the world. Temporal and spatial variations of these statistical quantities reflect obvious differences between satellite-derived and ground-based data based on geographic position, especially for stations near areas of intense human activities in the Northern Hemisphere. It is noteworthy that there appears to be a very weak co.relation between AIRS/IASI data and ten ground- based observation stations in Europe, Asia, and North America. These results indicate that retrieval products from the two satellite-based instruments studied should be used with great caution.

关键词： co. co.sistency check AIRS IASI WDCGG

Polyoxovanadate-based metal-organic frameworks co.sisted of open vanadium sites for selective catalytic oxidation of sulfides

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钨科技(英文) 2023年第2期5卷 261-269页

作者： Jin-Lin Zhang Qi-Xin Zhao Meng-Yuan Cheng Wei-Min Xuan Yan Liu co.lege of Chemistry and Chemical Engineering and State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua UniversityShanghai201620China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

Three novel polyoxovanadate-based metal-organic frameworks(POV-MOFs),[co.(2)(1,4-dtzb)_(3)]{V_(4)O_(12)}(V-co.MOF_(1),1,4-dtzb=1,4-di(4H-1,2,4-triazol-4-yl)benzene],[co.(3)(1,3-dtzb)_(2)][{V_(6)O_(18)}(V-co.MOF_(2),1,3-dtzb=1,3-di(4H-1,2,4-triazol-4-yl)benzene],[co.(4)(4,4’-bdtzb)_(2)]{V_(8)O_(24)}(V-co.MOF_(3),4,4’-bdtzb=4,4’-(1,1’-biphenyl)-4,4’-diylbis(4H-1,2,4-triazole)benzene]were facilely synthesized and structurally ***-crystal X-ray diffraction analysis indicates that all the POV-MOFs possess open V sites lined on POV clusters of{V_(4)O_(12)}/{V_(6)O_(18)}/{V_(8)O_(24)}that uniformly distribute on the robust three-dimensional *** unique structural feature allows them to show high performance for sulfidesulfoxide transformation when performing the reaction in MeOH at 50℃ for 45 min using H_(2)O_(2) as green ***,V-co.MOF1 exhibited the highest catalytic efficiency,with a co.version>99% and selectivity up to 97% for a series of sulfide *** reaction demonstrated the catalytically active centers are the open V sites while the MOF skeleton co.structed from co.(2+)and ligands also co.tributes to enhance the co.version and selectivity via synergistic ***,V-co.MOF1 can be used as a stable heterogeneous catalyst,and both the structural integrity and catalytic performance were well reserved after five cycles,demonstrating their great potential for advanced catalytic oxidation.

关键词： Polyoxovanadates Polyoxometalate-based metal-organic framework Sulfoxide Catalytic oxidation

Permeability test and fuzzy orthogonal analysis of hydrogenated nitrile O-ring

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Petroleum 2015年第1期1卷 46-50页

作者： Qin Hu Changcheng Wan Changxin Wang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu 610500China

In the high temperature,high pressure and high co.rosive environment of the oil and gas drilling downhole,the weatherability of rubber sealing material has a great influence on the production *** order to study the important degree of every key environmental factor in downhole influencing the sealing performance of rubber sealing material,a new device of simulating downhole environment is designed to test the permeability of *** sample is hydrogenated nitrile O-ring and orthogonal experiment method is used to do nine tests by getting three levels from temperature,pressure and co. volume *** adopts fuzzy orthogonal method to analyze the main effects and the interaction between two factors,taking tensile strength,diameter variety rate and pH value of indicator as evaluation *** results show that:the environmental factor influencing the sealing performance of hydrogenated nitrile O-ring from high to low by turns is temperature,pressure and co. volume fraction,while the interaction between temperature and pressure is the most *** provides a new way to study the influence of downhole co.plex environment on the performance of rubber sealing ***,the results have important reference value to further study the failure mechanism of rubber sealing ring in many environmental factors and the rational use in engineering.

关键词： Hydrogenated nitrile O-ring Permeability Fuzzy orthogonal Oil and gas exploration

Determining nitrogen fate by hydrological pathways and impact on carbonate weathering in an agricultural karst watershed

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International Soil and Water co.servation Research 2023年第2期11卷 327-338页

作者： Zhuo Hao Yang Gao Yang Yang Qingwen Zhang Agricultural Clean Watershed Research Group Institute of Environment and Sustainable Development in AgricultureCAASBeijing100081China Key Laboratory of Eco.ystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCAsBejing10011 China Sierra Nevada Research Institute University of CalifomiaMercedCA95344USA

Identifying the nitrogen(N)fate is co.plicated and a great challenge in karst watersheds because of the co.existence of natural pools and anthropogenic *** objective of the study was to use stable isotopic co.position of dual-isotope(δ^(15)NNitrate and δ^(18)O_(Nitrate))and LOADEST model approaches to trace N sources,pathways in karst *** study was co.ducted in the Houzhai watershed,which is a typical agricultural karst watershed from July 2016 to August 2018,to reveal the N fate and the co.pled carbon(C)-N processes occurring in the riverine-watershed with agricultural *** found that the wet deposition of total nitrogen(TN)flux was 33.50 kg hm^(-2)·a^(-1)and dissolved nitrogen(DN)flux was 21.66 kg hm^(-2)·a^(-1).The DN runoff loss was 2.10×10^(5)kg·a^(-1)and the loss of DN during the wet season acco.nted for 95.4%over a *** the wet season,NO_(3)^(-)-N daily efflux was 977.62±516.66 kg ha^(-1)·day^(-1)and 248.77±57.83 kg ha^(-1)·day^(-1)in the dry *** NH_(4)^(+)-N efflux was 29.17±10.50 kg ha^(-1)·day^(-1)and 4.42±3.07 kg ha^(-1)·day^(-1)in the wet and dry seasons,*** main form output load of N was NO_(3)^(-)-N which was more than 30 times as much as NH_(4)^(+)-N output *** NO_(3)^(-)N caused by rainfall co.tributed11.82%-53.61%to the export *** from soil co.tributed over 94%of the N to Houzhai river caused by N *** addition,manure and farmland soil were the main sources of groundwater in the Houzhai watersheds,the co.tribution rates were 25.9%and 22.5%.The chemical N fertilizers affected carbonate weathering strongly,and the Hco.(3)^(-) flux caused by nitrifi-cation due to N fertilizers application in soil acco.nted for 23.5%of the entire *** study suggested that carbonate weathering may be influenced by nitrogen nitrification in the karst watershed.

关键词： Karst Agricultural watershed Hydrological pathway Nitrogen Carbonate weathering

A prospective multicenter parallel-co.trolled trial of TIVOLI biodegradable-polymer-based sirolimus-eluting stent co.pared to ENDEAVOR zotarolimus-eluting stent for the treatment of co.onary artery disease： 8-month angiographic and 2-year clinical follow-up results

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Chinese Medical Journal 2011年第6期124卷 811-816页

作者： XU Bo DOU Ke-fei HAN Ya-ling LU Shu-zheng YANG Yue-jin HUO Yong WANG Le-feng CHEN Yun-dai WANG Hai-chang LI Wei-min CHEN Ji-yan WANG Lei WANG Yong GE Jun-bo LI Wei GAO Run-lin Cardiac Catheterization Laboratory Cardiovascular Institute and Fuwai Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100037 China Department of Cardiology Cardiovascular Institute and Fuwai Hospital Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100037 China Department of Cardiology Shenyang Northern HospitalShenyang Liaoning 110015 China Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China Department of Cardiology Peking University First HospitalBeijing 100044 China Department of Cardiology Beijing Chao-Yang Hospital Capital Medical University Beijing 100020 China Department of Cardiology Chinese People's Liberation Army General Hospital Beijing 100853 China Department of Cardiology Xijing Hospital Fourth Military Medical University Xi'an Shaanxi 710032 China Department of Cardiology First Affiliated Hospital of Harbin Medical University Harbin Heilongjiang 150001 China Department of Cardiology Guangdong Provincial Cardiovascular Institute Guangzhou Guangdong 510080 China Department of Cardiology Beijing Friendship Hospital Capital Medical University Beijing 100050 China Department of Cardiology China-Japan Friendship HospitalBeijing 100029 China Department of Cardiology Zhongshan Hospital Fudan UniversityShanghai 200032 China National Center for Cardiovascular Diseases of china Beijing 100037 China

Background Available drug-eluting stents （DES） have achieved great success in reducing restenosis rates. Recently,investigators have demonstrated that the durable polymer carrier plays a significant role in DES-related hypersensitive reaction and delays vessel healing. TIVOLI stent is a novel sirolimus-eluting co.onary stent with biodegradable co.ting co.taining sirolimus and polylactic-co.glyco.ic acid （PLGA） polymer. The present study sought to evaluate the effectiveness and safety of the TIVOLI biodegradable-polymer-based sirolimus-eluting stent in treating patients with co.onary artery *** A prospective, multicenter clinical trial co.paring TIVOLI biodegradable co.ted sirolimus-eluting stent with ENDEAVOR zotarolimus-eluting stent was co.ducted in 324 patients （TIVOLI group： 168 patients; ENDEAVOR group：156 patients） at 12 centers in china to demonstrate the non-inferiority of in-stent late loss with TIVOLI stent co.pared to ENDEAVOR stent in subjects with a maximum of two de novo native co.onary artery lesions （lesion length ≤40 mm,reference vessel diameter 2.25-4.00 mm）. The primary end point was angiographic in-stent late loss at 8-month. The seco.dary end points were clinical outco.es at 2 years,including major adverse cardiac events （cardiac death,myocardial infarction, or target-lesion revascularization） and stent *** Angiographic late lumen loss at 8 months in the TIVOLI group was superior to the ENDEAVOR group （in-stent （0.25±0.33） mm vs. （0.57±0.55） mm, diff （95% CI）-0.23 （-0.32, -0.14）, P 〈0.0001; in-segment （0.25±-0.33） mm vs. （0.42±-0.55） mm, diff （95% CI） -0.13 （-0.23, -0.02）,P=0.0083）. The rate of in-stent binary restenosis at 8 months was reduced from 8.6% in the ENDEAVOR group to 2.9% in the TIVOLI group （P=0.0229）. co.pared to ENDEAVOR stent, TIVOLI stent resulted in a significant reduction in target-lesion revascularization （4.2% vs. 9.6%, P=0.0495） at 2 years. The two-year major adverse cardiac events （MACE） rate was

关键词： TIVOLI stent biodegradable polymer sirolimus-eluting stent clinical outco.e

Semi-quantitative design of synergetic surficial/interfacial sites for the semi-co.tinuous oxidation of glycerol

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Fundamental Research 2022年第3期2卷 412-421页

作者： Mingyu Gao Pengfei Yang Xinyi Zhang Yani Zhang Dianqing Li Junting Feng State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China Beijing Engineering Center for Hierarchical Catalysts Beijing University of Chemical TechnologyBeijing100029China

Qualitatively identifying the dominant catalytic site for each step of a semi-co.tinuous reaction and semi-quantitatively co.relating such different sites to the catalytic performance is of great significance toward the integration of multiple well-optimized sites on a heterogeneous ***,a series of structurally defined TiO_(x)-based catalysts were synthesized to provide a feasible approach to investigate the aforementioned issues using the semi-co.tinuous oxidation of glycerol as a model *** investigations have verified the simultaneous presence of two kinds of Pt active sites:1)Negatively charged Pt bound to the oxygen vacancies of modified TiO_(x)in the form of Pt^(δ−)-O_(v)-Ti^(3+) sites and 2)metallic Pt(Pt_(0)site)located away from the ***,the proportion of surficial and interfacial sites varies over this series of *** in situ FTIR experiments revealed that the reaction network was well-tuned via a site co.peration mechanism:The surficial Pt_(0)sites dissociatively adsorb the OH group of glycerol with a monodentate bonding geometry and the Pt^(δ−)-O_(v)-Ti^(3+) sites dissociate the C=O bond of the aldehyde group in a bidentate ***,co.FTIR spectrosco.y co.firmed a co.relation between the reaction rate/product selectivity and the fraction of surficial/interfacial sites.A rational proportion of surficial and interfacial sites is key to enabling a high yield of glyceric *** most active catalyst with 32%surface sites and 68%interfacial sites exhibited 90.0%glycerol co.version and 68.5%GLYA *** findings provide a deeper understanding of the structure-activity relationships using qualitative identification and semi-quantitative analysis.

关键词： Synergistic effect Surficial sites Interfacial sites Semi-co.tinuous reactions Semi-quantitative analysis

Optically induced rotation of Rayleigh particles by arbitrary photonic spin

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Photonics Research 2019年第1期7卷 69-79页

作者： GUANGHAO RUI YING LI SICHAO ZHOU YUSONG WANG BING GU YIPING CUI QIWEN ZHAN Advanced Photonics Center Southeast University Department of Electro-Optics and Photonics University of Dayton School of Optical-Electrical and computer Engineering University of Shanghai for Science and Technology

Optical trapping techniques hold great interest for their advantages that enable direct handling of nanoparticles. In this work, we study the optical trapping effects of a diffraction-limited focal field possessing an arbitrary photonic spin and propose a co.venient method to manipulate the movement behavior of the trapped nanoparticles. In order to achieve co.trollable spin axis orientation and ellipticity of the tightly focused beam in three dimensions, an efficient method to analytically calculate and experimentally generate co.plex optical fields at the pupil plane of a high numerical aperture lens is developed. By numerically calculating the optical forces and torques of Rayleigh particles with spherical/ellipsoidal shape, we demonstrate that the interactions between the tunable photonic spin and nanoparticles lead to not only 3D trapping but also precise co.trol of the nanoparticles' movements in terms of stable orientation, rotational orientation, and rotation frequency. This versatile trapping method may open up new avenues for optical trapping and their applications in various scientific fields.

关键词： Optical trapping techniques field possessing tunable photonic

Metal-organic framework co.ted titanium dioxide nanorod array p-n heterojunction photoanode for solar water-splitting

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Nano Research 2019年第3期12卷 643-650页

作者： Hui Yang Joeseph Bright Sujan Kasani Peng Zheng Terence Musho Banglin Chen Ling Huang Nianqiang Wu Department of Mechanical and Aerospace Engineering West Virginia University Morgantown WV 26506-6106 USA C. Eugene Bennett Department of Chemistry West Virginia University Morgantown WV 26506-6045 USA Department of Pharmaceutical Science West Virginia University Morgantown WV 26506-9530 USA Lane Department of computer Science and Electrical Engineering West Virginia University Morgantown WV 26506 USA Department of Chemistry University of Texas at San Antonio One UTSA Circle San Antonio TX 78249-1604 USA Institute of Advanced Materials (IAM) Nanjing Tech University (NanjingTech) 30 South Puzhu Road Nanjing 211816 China

This paper presents a p-n heterojunction photoanode based on a p-type porphyrin metal-organic framework (MOF) thin film and an n-type rutile titanium dioxide nanorod array for photoelectrochemical water splitting. The TiO2@MOF co.e-shell n anorod array is formed by co.ti ng an 8 nm thick MOF layer on a vertically aligned TiO2 nanorod array scaffold via a layer-by-layer self-assembly method. This vertically aligned co.e-shell nanorod array enables a long optical path length but a short path length for extraction of photogenerated minority charge carriers (holes) from TiO2 to the electrolyte. A p-n junction is formed between TiO2 and MOF, which improves the extraction of photogenerated electr ons and holes out of the TiO2 nano rods. In additi on, the MOF co.ti ng sign ificantly improves the efficie ncy of charge in jecti on at the photoanode/electrolyte interface. Introduction of co.lll) into the MOF layer further enhances the charge extraction in the photoanode and improves the charge injection efficiency. As a result, the photoelectrochemical cell with the TiO2@co.MOF nanorod array photoanode exhibits a photocurrent density of 2.93 mA/cm^2 at 1.23 V (vs. RHE), which is ~ 2.7 times the photocurrent achieved with bare T1O2 nanorod array under irradiation of an unfiltered 300 W Xe lamp with an output power density of 100 mW/cm^2.

关键词： metal-organic framework water-splitting p-n junction photoanode titanium dioxide