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Ancient road transport devices： Developments from the Bronze Age to the Roman Empire

Frontiers of Mechanical Engineering 2016年第1期11卷 12-25页

作者： Cesare ROssi Thomas g. CHONDROs Kypros F. MiLiDONis sergio sAViNO Flavio RUssO Department of industrial Engineering University of Naples 'Federico II' Naples 80125 Italy Mechanical Engineering & Aeronautics Department University of Patras Patras 26500 Greece UssME Consultant via Lamaria 137 Torte del Greco Napoli Italy

The development of transportation systems has significantly enhanced the welfare and modernization of society. Wooden vehicles pulled by animals have been used for land transportation since the early Bronze Age. Whole-body gharries with rigid wheels pulled by oxen appeared in Crete by 2000 BC or earlier. Horses originating from the East were depicted in early Cretan seal-rings of the same period. The two-wheeled horse- drawn chariot was one of the most important inventions in history. This vehicle provided humanity its first concept of personal transport and was the key technology of war for 2000 years. Chariots of Mycenaean and Archaic greece with light and flexible four-spoked wheels acting as spring suspensions were depicted in vase paintings. The development of this vehicle incorporated the seeds of a primitive design activity and was important for engineering. The Trojan horse since 1194 BC and the helepolis since 700 BC were the first known machines on a wheeled base transported by horses or self-powered. Ancient engineers invented bearings lubricated with fat, and Romans introduced the ancestors of ball bearings for their wagons and carts. The historic evolution of wheeled transportation systems, along with early traction, suspension, and braking systems, is presented in this paper. Analytical and numerical methods are incorporated to analyze the most conceivable loading situations of typically reconstructed wheeled transportation systems in ancient times. Traction requirements both for horse-driven machines and the power for internal motors are also analyzed. This study can serve as a basis for further development of detailed reconstruction of transportation systems in antiquity.

关键词： transportation wheel spoke cart axle bearing

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Kr and Xe isotopic compositions of Fe-Mn crusts from the western and central Pacific Ocean and implications for their genesis

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Acta Oceanologica sinica 2014年第8期33卷 26-33页

作者： BU Wenrui sHi Xuefa Li Li ZHANg Mingjie g.P.glasby LiU Jihua Key Laboratory of Marine sedimentology & Environmental geology First Institute of OceanographyState Oceanic Administration school of Resources and Environment Lanzhou University Department of geochemistry Geowissenschafliches Zentrum der Universitat G?ttingen (GZG)G?ttingen 37077Germany

Kr and Xe nuclide abundance and isotopic ratios of the uppermost layer of Fe-Mn Crusts from the western and central Pacific Ocean have been determined. The results indicate that the Kr and Xe isotopic composi-tions, like that of He, Ne and Ar, can be classified into two types： low3He/4He type and high3He/4He type. The low3He/4He type crusts have low84Kr and132Xe abundance, while the high3He/4He type crusts have high84Kr and132Xe abundance. The82Kr/84Kr ratios of the low3He/4He type crusts are lower than that of the air, while the83Kr/84Kr and86Kr/84Kr ratios are higher than those of the air. The Kr isotopic ratios of the high-er3He/4He type crusts are quite similar to those of the air. The128Xe/132Xe,130Xe/132Xe and131Xe/132Xe ratios of the low3He/4He type sample are distinctly lower than those of the air, whereas the129Xe/132Xe,134Xe/132Xe and136Xe/132Xe ratios are higher than those of the air. The low3He/4He type samples have the diagnostic characteristics of the MORB, with excess129, 131, 132, 134, 136Xe relative to130Xe compared with the solar wind. The128Xe/132Xe,130Xe/132Xe and131Xe/132Xe ratios of the high3He/4He type samples are slightly higher than those of the air, and the129Xe/132Xe,134Xe/132Xe and136Xe/132Xe ratios are qiute similar to those of the air. The noble gases in the Fe-Mn crusts are derived from the lower mantle, and they are a mixture of lower mantle primitive component, radiogenic component and subduction recycled component. The helium isotopic ra-tios of the low mantle reservoir are predominantly controlled by primitive He （3He） and U and Th radiogenic decayed He （4He）, but the isotopic ratios of the heavier noble gases, such as Ar, Kr and Xe, are controlled to different extent by recycling of subduction components. The difference of the noble isotopic compositions of the two type crusts is the result of the difference of the noble isotopic composition of the mantle source reservoir underneath the seamounts the crusts occurred, the noble gas

关键词： Fe-Mn crusts Kr and Xe isotopes mantle reservoir Pacific Ocean subduction recycling

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Evaluation of bearing, gears and gearboxes performance with different wind turbine gear oils

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Friction 2015年第4期3卷 275-286页

作者： Ramiro Carneiro MARTiNs Carlos M.C.g.FERNANDEs Jorge H.O.sEABRA iNEgi Universidade do PortoPortoPortugal Faculdade de Engenharia Universidade do PortoPortoPortugal

The oil viscosity specification for wind turbine gear oils is isO Vg 320,although there are quite different viscosity indexes oils for that viscosity *** work evaluates the behaviour of different base oil formulations,since polyalphaolefin(PAO),mineral,ester and polyalkeleneglycol(PAg)that withstand quite different viscosity *** oils evaluation was done in rolling bearing tests and gear *** behaviour was compared for operating conditions in the range observable in a wind turbine *** experimental results showed considerable differences between the different oils and it was observed that depending on the contact type the relative behaviour of the lubricants would change,i.e.,the best lubricant for the rolling bearing would not imply the best result on the gear *** gear geometry is also very important toward the transmission efficiency,once using a low loss gear concept a decrease of up to 25%in torque loss could be *** models were implemented with the purpose of performing a better simulation of the mechanical system and also to obtain the friction coefficient promoted by the tested oils.

关键词： gears rolling bearings friction coefficient lubricants efficiency

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Determination of the Biosorption of Cd（ ii ） by Coconut Fiber

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Journal of Agricultural science and Technology(B) 2014年第4期4卷 291-298页

作者： Dany g. Kramer Brismark g. Rocha Mirian C. s. Pereira Renata s. D. souza Carlos R. Alves geraldo B. C. Junior Jose Heriberto O. Nascimento Margarida J. Quina Licinio g. Ferreira Rasiah Ladchumananandasivam Technology Center Mechanical Engineering Federal University of Rio Grande do Norte Natal 59.072-970 RN Brazil Centre of Chemical Processes Engineering and Forest Products (CiEPQPF) University of Coimbra Coimbra 3030- 790 Portugal Faculdade de CiOncias da safide do Trairi Federal University of Rio Grande do Norte (UFRN) Santa Cruz 59000-200 RNBrazil Laboratory of Cellular Ultra structure Oswaldo Cruz Institute Fundation (FIOCR UZ) Rio de Janeiro 21040-360 R J Brazil Department of Clinical Analysis Federal University of Rio Grande do Norte Natal 59.072-970 RN Brazil Department of Textile Engineering Federal University of Rio Grande do Norte Natal 59.072-970 RN Brazil

The coconut fiber is produced in large quantities in Brazil, even though very small quantities are being used by some industries, mainly cordage mats and handicrafts. An alternative usage would be the use of these fibers in biosorption of heavy metals from aqueous solutions. This present study aimed to evaluate the potentiality of cadmium biosorption by coconut fiber. The coconut fibers were used at kinetic analysis, influence ofpH and adsorption isotherms were also carried out. it can be concluded that there is great potential for the use of coconut fiber, and the optimum pH for adsorption was around 5.0. The adsorption kinetics is fast and equilibrium occurs within 120 min. The Langmuir isotherm was considered the most suitable to describe the experimental data.

关键词： Coconut fiber biosorption cadmium.

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spectral and Timing Analysis of the Black Hole Transient MAXi J1631–479 During its 2019 Outburst Observed with insight-HXMT

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Research in Astronomy and Astrophysics 2022年第11期22卷 21-33页

作者： Yu-Cong Fu L.M.song g.Q.Ding s.N.Zhang J.L.Qu s.Zhang L.Zhang Q.C.Bu Y.Huang X.Ma Z.X.Yang Y.L.Tuo X.F.Lu D.K.Zhou B.Y.Wu T.M.Li Y.C.Xu Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqiXinjiang 830011China University of Chinese Academy of sciences Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China institut fur Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitatSand 1D-72076 TübingenGermany

We report spectral and timing analysis of the black hole transient MAXi J1631–479 during the hard intermediate state of its 2019 outburst from the insight-Hard X-ray Modulation Telescope(insight-HXMT)*** find that the energy dependence of the type-C quasi-periodic oscillation(QPO)frequency evolves with time:during the initial rise of a small flare(~MJD 58526.0-58527.1),the QPO frequency increases with increasing energy from~1 to~100 ke V,and then the frequency remains constant after MJD *** discover a possible new phenomenon of Fe line’s QPO frequency jump that has never been observed for other black hole transients:during the small flare,the QPO frequency around the Fe line energy is higher than any other energy band,with the frequency difference Δf=0.25±0.08 Hz between 5.5–7.5 ke V and other energy *** spectral analysis shows that the evolution of QPOs is related to the equivalent width of the narrow Fe line,and its equivalent width increases during this small *** propose that the QPO frequency difference results from the differential precession of a vertically extended jet,and the higher QPO frequency of Fe line could be caused by the layered jet when the jet scale *** the same time,the evolution of QPOs is related to the accretion rate,while the energy dependence of QPOs supports the existence of deceleration in the vertically distributed jet.

关键词： accretion accretion disks stars:black holes X-rays:binaries

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Evolving management of metaplasia and dysplasia in Barrett's epithelium

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World Journal of gastroenterology 2016年第47期22卷 10316-10324页

作者： Richard PT Evans Moustafa Mabrouk Mourad simon g Fisher simon R Bramhall Department of surgery the Wye Valley NHS Trust

Oesophageal cancer affects more than 450000 people worldwide and despite continued medical advancements the incidence of oesophageal cancer is increasing. Oesophageal cancer has a 5 year survival of 15%-25% and now globally attempts are made to more aggressively diagnose and treat Barrett's oesophagus the known precursor to invasive disease. Currently diagnosis the of Barrett's oesophagus is predominantly made after endoscopic visualisation and histopathological confirmation. Minimally invasive techniques are being developed to improve the viability of screening programs. The management of Barrett's oesophagus can vary greatly dependent on the presence and severity of dysplasia. There is no consensus between the major international medical societies to determine and agreed surveillance and intervention pathway. in this review we analysed the current literature to demonstrate the evolving management of metaplasia and dysplasia in Barrett's epithelium.

关键词： Barrett’s Oesophagus Dysplasia Metaplasia Oesophageal cancer

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不同软组织密度值对纵隔占位病变鉴别诊断的意义

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放射学实践 1992年第2期7卷 47-53页

作者： J.gorich s.A.Beyer-Enke g.Layer U.Haberkorn g.van Kaick 张良华 institut fur Radiologie und Pathophysiologie Deutsches KrebsforschungszentrumIm Neuenheimer Feld 2806900 HeidelbergFRG 同济医科大学附属同济医院

CT对纵隔占位病变的定位很确切,密度分辨力能提供进一步鉴别诊断的依据.

关键词：纵隔占位病变软组织密度值诊断

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Differentiated payments for environmental services schemes: A methodology proposal

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Journal of Mountain science 2018年第8期15卷 1693-1710页

作者： Carlos R.AgUiLAR-góMEZ sergio FRANCO-MAAss Tizbe T.ARTEAgA-REYEs Agrolivestock sciences and Rural institute Autonomous University of the State of Mexico

Payment schemes for environmental services face serious budget constraints in Mexico. Payments are equally distributed among forest owners, and the governmental agencies that make payments to beneficiaries do not evaluate the amount of environmental services produced by forested areas. This lack of evaluation could lead to economic and environmental deficiencies that restrict the possible benefits of such programmes. in general, these programmes do not achieve their conservation objectives, and local beneficiaries are not involved in the design or application of these programmes. similarly, the Payments for Hydrological Environmental services(PHEs) programme of the state of Mexico, Mexico, makes equal payments to beneficiaries of forested areas considering tree density. The objective of the present work was to create a methodology for determining differentiated payments schemes for hydrological environmental services, prioritising areas that contribute the most to groundwater recharge and promote the participation of society. in the Nevado de Toluca Natural Protected Area, the environmental criteria of forest type, tree density and aquifer overexploitation as well as social participation were considered in a multi-criteria analysis implemented in a geographic information system. A methodology was developed to determine differentiated payments based on specific forest characteristics that influence the potential capacity of forests to recharge groundwater reserves in addition to the level of social participation. in particular, social participation is key as it could ensure the viability of PHEs programmes as conservation alternatives in forested areas with high groundwater recharge potential.

关键词： Differentiated payments Environmental services Mountain systems Multi-criteria analysis social participation

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Association of electrocardiographic markers with myocardial fibrosis as assessed by cardiac magnetic resonance in different clinical settings

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World Journal of Cardiology 2022年第9期14卷 483-495页

作者： george Bazoukis sebastian garcia-Zamora gökselÇinier sharen Lee Enes Elvin gul JesúsÁlvarez-garcía gabi Miana Mertilker Hayıroğlu gary Tse Tong Liu Adrian Baranchuk Department of Cardiology Larnaca General HospitalLarnaca 6036Cyprus Department of Basic and Clinical sciences University of Nicosia Medical SchoolNicosia 2414Cyprus Department of Cardiology Delta ClinicSanta Fe 341Argentina Department of Cardiology Dr.Siyami Ersek Thoracic and Cardiovascular Surgery Training and Research CenterIstanbul 34668Turkey Cardiovascular Analytics group Laboratory of Cardiovascular PhysiologyHong Kong 999077China Division of Cardiac Electrophysiology Madinah Cardiac CentreMadinah 42351Saudi Arabia Department of Cardiology Ramon y Cajal University HospitalMadrid 28034Spain Telehealth Center of Hospital das Clínicas Hong Kong 999077China Kent and Medway Medical school CanterburyCanterbury CT27FSUnited Kingdom Tianjin Key Laboratory of ionic-Molecular Function of Cardiovascular Disease Department of CardiologyTianjin Institute of CardiologySecond Hospital of TianjinTianjin Medical UniversityTianjin 300211China Department of Cardiology The Second Hospital of Tianjin Medical UniversityTianjin 300211China Department of Cardiology Queen's UniversityOntario K7L 3N6Canada

BACKgROUND Cardiac magnetic resonance(CMR)is a unique tool for non-invasive tissue characterization,especially for identifying *** To present the existing data regarding the association of electrocardiographic(ECg)markers with myocardial fibrosis identified by CMR-late gadolinium enhancement(LgE).METHODs A systematic search was performed for identifying the relevant studies in Medline and Cochrane databases through February *** addition,we conducted a relevant search by Reference Citation Analysis(RCA)(https://***).REsULTs A total of 32 studies were *** hypertrophic cardiomyopathy(HCM),fragmented QRs(fQRs)is related to the presence and extent of myocardial *** and abnormal Q waves are associated with LgE in ischemic cardiomyopathy patients,while fQRs has also been related to fibrosis in *** score,abnormal Q waves,and notched QRs have also been associated with *** abnormalities as reflected by increased Tp-Te,negative Twaves,and higher QT dispersion are related to myocardial fibrosis in HCM *** patients with Duchenne muscular dystrophy,a significant correlation between fQRs and the amount of myocardial fibrosis as assessed by LgE-CMR was *** atrial fibrillation patients,advanced inter-atrial block is defined as P-wave duration≥120 ms,and biphasic morphology in inferior leads is related to left atrial *** Myocardial fibrosis,a reliable marker of prognosis in a broad spectrum of cardiovascular diseases,can be easily understood with an easily applicable ***,more data is needed on a specific disease basis to study the association of ECg markers and myocardial fibrosis as depicted by CMR.

关键词： Myocardial fibrosis Late gadolinium enhancement Electrocardiogram Cardiac magnetic resonance

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Thermal shock and fatigue behavior of pressureless sintered Al_(2)O_(3)-siO_(2)-ZrO_(2) composites

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Journal of Advanced Ceramics 2015年第3期4卷 190-198页

作者： g.MEBRAHiTOM AsMELAsH O.MAMAT F.AHMAD A.K.PRAsADA RAO Faculty of Manufacturing Engineering Universiti Malaysia PahangPekanPahangMalaysia Universiti Teknologi PETRONAs Bandar Seri Iskandar31750 TronohPerakMalaysia

The thermal shock and fatigue behavior of pressureless sintered Al_(2)O_(3)-siO_(2)-ZrO_(2)(AsZ)composites was *** influence of the thermal shock and fatigue on the strengthening response of AsZ has been investigated by measuring the strength retention and microstructural *** magnitude of the flexural strength and fracture of the AsZ has been compared with that of the monolithic Al_(2)O_(3)(A)and Al_(2)O_(3)-siO_(2)-ZrO_(2)(AZ)composites under the same experimental *** indicated that the AsZ composites possess the highest resistance against thermal shock and fatigue,in comparison with A and *** improvements were attributed to the enhancement in the fracture toughness of AsZ and the presence of multi-phase reinforcement.

关键词： ceramics flexural strength fracture toughness pressureless sintering thermal fatigue thermal shock

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