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The influence of various grease compositions and silver nanoparticle additives on electrically induced rolling-element bearing damage

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Friction 2024年第4期12卷 796-811页

作者： Samuel BOND Robert L.jackson German MILLS Department of Chemistry and Biochemistry Auburn UniversityAuburn 36849-5412USA Department of Mechanical Engineering Auburn UniversityAuburn 36849-5412USA

Leakage currents accelerate surface degradation of metal contacts via small scale arcing across lubricating films,but recent observations suggest that metallic nanoparticle additives in lubricants may be useful to improve contact *** findings prompted a study that examined electrically induced surface pitting of steel contacts in the presence of several lubricating greases including some containing nanometer-sized colloidal silver(Ag)*** rolling sphere-on-disk experiments were conducted under electro-tribological loads employing polyurea greases derived from mineral and synthetic base oils with and without *** forces and electrical resistance were monitored continuously during the tests;surface changes were characterized by means of optical spectroscopy,stylus profilometry,and scanning electron microscopy(SEM)including compositional analysis using energy dispersive spectroscopy(EDS).The observations demonstrate that surface pitting induced by arcing occurs mainly at the points were the rolling motion changes direction and that eroded metal is deposited along the wear ***-sized pits are formed which contain carbon and oxygen indicating that arcing causes decomposition of the hydrocarbon *** findings indicate a significant inhibition of pitting is induced by the Ag nanoparticles;some greases containing other additives exhibit a similar,although less pronounced,effect.

关键词： electric motor bearings wheel bearings electric vehicles arcing electrically induced bearing damage pitting leakage current stray current

OneGeology： from concept to reality

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Episodes 2008年第3期31卷 344-345页

作者： jackson, Ian British Geol Survey Nottingham NG12 5GG England

In the March 2007 edition of Episodes, an article described the origins of OneGeology and progress during its first 12 months. Since March 2007, the project has moved forward dramatically and in August 2008, at the 33... 详细信息

关键词：地质学实验研究项目计划科学家

Simulated perturbation in the sea-to-air flux of dimethylsulfi de and the impact on polar climate

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Journal of Oceanology and Limnology 2021年第1期39卷 110-121页

作者： Bo QU Albert JGABRIC Rebecca jackson School of Science Nantong UniversityNantong 226219China School of Environment and Science Griffi th UniversityBrisbane 4111QLDAustralia

Marine biogenic emission of dimethylsulfi de(DMS)has been well recognized as the main natural source of reduced sulfur to the remote marine atmosphere and has the potential to aff ect climate,especially in the polar *** used a global climate model(GCM)to investigate the impact on atmospheric chemistry from a change to the contemporary DMS fl ux to that which has been projected for the late 21 st *** perturbed simulation corresponded to conditions that pertained to a tripling of equivalent CO 2,which was estimated to occur by year 2090 based on current worst-case greenhouse gas emission *** changes in zonal mean DMS fl ux were applied to 50°S–70°S Antarctic(ANT)and 65°N–80°N Arctic(ARC)*** results indicate that there are clearly diff erent impacts after perturbation in the southern and northern polar *** quantities related to the sulfur cycle show a higher increase in ***,most sulfur compounds have higher peaks in *** perturbation in DMS fl ux leads to an increase of atmospheric DMS of about 45%in ANT and 33.6%in *** sulfur dioxide(SO 2)vertical integral increases around 43%in ANT and 7.5%in ***(SO 4)vertical integral increases by 17%in ANT and increases around 6%in *** emissions increases by 21%in ANT and increases by 9.7%in ***,oxidation of DMS by OH increases by 38.2%in ARC and by 15.17%in *** optical depth(AOD)increases by 4%in the ARC and by 17.5%in the ANT,and increases by 22.8%in austral *** importance of the perturbation of the biogenic source to future aerosol burden in polar regions leads to a cooling in surface temperature of 1 K in the ANT and 0.8 K in the ***,polar regions in the Antarctic Ocean will have a higher off setting eff ect on warming after DMS fl ux perturbation.

关键词： dimethylsulfi de(DMS) sulfur dioxide DMS sea-to-air fl ux perturbation global climate model(GCM) polar region

A Framework for Disaster Vulnerability in a Small Island in the Southwest Pacific: A Case Study of Emae Island, Vanuatu

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International Journal of Disaster Risk Science 2017年第4期8卷 358-373页

作者： Guy jackson Karen McNamara Bradd Witt School of Earth and Environmental Science The University of Queensland

The societal costs of disasters around the world are continuing to increase and Pacific Island countries are considered some of the most vulnerable. This is primarily due to a combination of high hazard exposure coupled with a range of social, economic, physical, and political vulnerabilities. This article contributes to the growing body of work that aims to understand the causal factors of disaster vulnerability, but with a specific focus on small island developing states. The article first develops a framework for understanding disaster vulnerability, drawing on extensive literature and the well-established Methods for the Improvement of Vulnerability in Europe(MOVE)framework, and second, applies this adapted framework using empirically-derived data from fieldwork on Emae Island, Vanuatu to provide a working understanding of the causal elements of disaster vulnerability. Drawn from a significant body of scholarship at the time, the MOVE framework was primarily developed as a heuristic tool in which disaster vulnerability is considered to be a function of exposure, susceptibility(socially, economically, physically, culturally, environmentally, institutionally), and a lack of resilience. We posit that this adapted framework for small islands should also include historical susceptibility,and we prefer livelihood resilience(as capabilities, social capital, knowledge, participation, and human rights) over lack of resilience. We maintain that understanding disaster vulnerability holistically, which is inclusive of both strengths and drawbacks, is crucial to ensure that limited resources can target the causal factors that produce vulnerability and help safeguard and improve livelihoods in both the short and long term.

关键词： Disaster risk reduction Disaster vulnerability Livelihood resilience Small islands Vanuatu

Development of a brownfield inventory for prioritizing funding outreach in Tucson,Arizona

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Geo-Spatial Information Science 2021年第4期24卷 742-754页

作者： Theresa Foley Ann Marie Wolf Chloe jackson Ryan Stephenson Sonora Environmental Research Institute Inc.(SERI)TucsonAZUSA Pima County ITD/GIS TucsonAZUSA Pima County Community Development&Neighborhood Conservation TucsonAZUS

Fear of liability from the 1980 Comprehensive Environmental Response,Compensation,and Liability Act(CERCLA or Superfund)has prompted developers to build preferentially upon undeveloped green space rather than potentially contaminated former industrial sites,leading to urban sprawl in the suburban areas while blighted properties in the urban core remain vacant.A brownfield is defined as a property in which the presence or potential presence of a hazardous substance or contaminant poses a barrier to *** often create brownfield inventories by performing a site suitability analysis,using distinguishing features such as ecolo-gically and culturally significant areas or neighborhoods that need *** County,Arizona and the Sonora Environmental Research Institute,Inc.(SERI)developed a brownfield inventory of the large,industrial area directly to the west of Davis-Monthan Air Force *** the brownfield target area has few residential neighborhoods and lacks the distinguish-ing features usually used in a brownfield site suitability analysis,the county and SERI used the official tax assessor database and 11 federal,state and county environmental databases to develop a brownfield *** goal of the project was to prioritize properties that stood to benefit from the grant *** final brownfield inventory contained 531 parcels.

关键词： GIS site suitability analysis brownfield urban planning brownfield inventory

Cultivating potential:Harnessing plant stem cells for agricultural crop improvement

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Molecular Plant 2024年第1期17卷 50-74页

作者： Penelope Lindsay Kyle W.Swentowsky David jackson Cold Spring Harbor Laboratory Cold Spring HarborNY 11724USA National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhanHubei430070China

Meristems are stem cell-containing structures that produce all plant organs and are therefore important targets for crop *** regulators control the balance and rate of cell divisions within the *** these regulators impacts meristem architecture and,as a consequence,plant *** this review,we discuss genes involved in regulating the shoot apical meristem,inflorescence meristem,axillary meristem,root apical meristem,and vascular cambium in *** highlight several examples showing how crop breeders have manipulated developmental regulators to modify meristem growth and alter crop traits such as inflorescence size and branching *** transformation techniques are another innovation related to plant meristem research because they make crop genome engineering *** discuss recent advances on plant transformation made possible by studying genes controlling meristem ***,we conclude with discussions about how meristem research can contribute to crop improvement in the coming decades.

关键词： meristem crop improvement plant transformation plant breeding crop yield gene editing

Metagenomic markings of myeloid malignancies

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Genes & Diseases 2023年第1期10卷 4-6页

作者： An Dinh Duy Nguyen Maryssa Shanteau-jackson Thomas LaFramboise Department of Genetics and Genome Sciences School of MedicineCase Western Reserve UniversityClevelandOH44106USA

Human microbiome studies have exploded in number in recent years with the advent of high-throughput sequencing *** dramatic increase in sensitivity facilitated by deep-sequencing capability has led to hundreds of studies characterizing microbial communities in multiple human tissues,as well as the relationships between the composition of these communities and disease.

关键词： methods. myeloid hundreds

Future sea level rise along the coast of China and adjacent region under 1.5℃ and 2.0℃ global warming

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Advances in Climate Change Research 2020年第3期11卷 227-238页

作者： QU Ying LIU Yonggang Svetlana JEVREJEVA Luke P.jackson Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijing100871China National Oceanography Center LiverpoolL35DAUK Programme for Economic Modelling Nuffield CollegeOxford UniversityOX1 INFUK

Although future sea level rise along the China coast has been projected by various studies for different representative concentration pathways(RCPs),the projections for different warming thresholds,e.g.1.5℃ and 2.0℃,have not been done specifically for this region,to the best of our *** provide such a projection here based on the climate projections of Coupled Model Intercomparison Project Phase 5(CMIP5).The projections are given for 20 tide-gauge stations along the coast of China,Korea,Japan,and *** land motion(VLM)is also estimated for stations that have tide gauge records and satellite altimetry both covering the period of *** land motion(LLM)is then estimated by subtracting the land motion due to glacial isostatic adjustment(GIA)from *** considering LLM,sea level rise by 2100 at median probability is projected to be 38-49 cm relative to the average sea level over 1986-2005 under warming of 1.5℃,and increase to 46-57 cm when the warming threshold is increased to 2.0℃.The steric component is the main contributor to this increase in sea *** of LLM will not affect the sea level increase between the two warming thresholds,but it will make the local sea level rise by 2100 at certain locations substantially higher(up to 36 cm)or lower(up to 13 cm).

关键词： Sea level rise Coast of China Tide gauge records Vertical land motion Warming of 1.5℃ Warming of 2.0℃

Spatial pattern analysis of forest trees based on the vectorial mark

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Journal of Forestry Research 2022年第4期33卷 1301-1315页

作者： Honglu Xin Toby jackson Yujie Cao Huanyuan Zhang Yi Lin Alexander Shenkin Institute of Remote Sensing and Geographic Information Systems School of Earth and Space SciencePeking UniversityBeijing 100871People’s Republic of China Environmental Change Institute School of Geography and the EnvironmentUniversity of OxfordSouth Parks RoadOxford OX13QYUK Department of Plant Sciences University of CambridgeDowning StreetCambridge CB23EAUK College of Surveying and Geo-Informatics Tongji UniversityShanghai 200092People’s Republic of China SICCS Northern Arizona UniversityFlagstaffAZ 86001USA

Analysis of spatial patterns to describe the spatial correlation between a tree location and marks(i.e.,structural variables),can reveal stand history,population dynamics,competition and ***,most studies of spatial patterns have concentrated on tree location and tree sizes rather than on crown asymmetry especially with direct analysis among marks characterizing facilitation and competition among of trees,and thus cannot reveal the cause of the distributions of tree locations and quantitative *** explore the spatial correlation among quantitative and vectorial marks and their implication on population dynamics,we extracted vertical and horizontal marks(tree height and crown projection area)characterizing tree size,and a vectorial mark(crown displacement vector characterizing the crown asymmetry)using an airborne laser scanning point cloud obtained from two forest stands in Oxfordshire,*** and vectorially marked spatial patterns were developed,with corresponding null models established for a significance *** analyzed eight types of univariate and bivariate spatial patterns,after first proposing four *** accuracy of the pattern analysis based on an algorithm-segmented point cloud was compared with that of a truly segmented point *** algorithm-segmented point cloud managed to detect 70–86%of patterns *** eight types of spatial patterns analyzed the spatial distribution of trees,the spatial correlation between tree size and facilitated or competitive interactions of sycamore and other *** four types of univariate patterns jointly showed that,at smaller scales,the trees tend to be clustered,and taller,with larger crowns due to the detected facilitations among trees in the study *** four types of bivariate patterns found that at smaller scales there are taller trees and more facilitation among sycamore and other species,while crown size is mostly homogeneous across *** results indicate that

关键词： Spatial pattern Spatial correlation Quantitative mark Vectorial mark Summary statistics