检索结果-南通市图书馆

Designing healthy communities： Testing the walkability model

在线全文

学校读者我要写书评

暂无评论

Frontiers of Architectural Research 2017年第1期6卷 63-73页

作者： Adriana A. Zuniga-Teran barron j. orr Randy H. Gimblett Nader V. Chalfoun Stuart E. Marsh David P. Guertin Scott B. Going Udall Center for Studies in Public Policy University of Arizona Tucson AZ 85719 USA

Research from multiple domains has provided insights into how neighborhood design can be improved to have a more favorable effect on physical activity, a concept known as walkability. The relevant research findings/hypotheses have been integrated into a Walkability Framework, which organizes the design elements into nine walkability categories. The purpose of this study was to test whether this conceptual framework can be used as a model to measure the interactions between the built environment and physical activity. We explored correlations between the walkability categories and physical activity reported through a survey of residents of Tucson, Arizona （n=486）. The results include significant correlations between the walkability categories and physical activity as well as between the walkabi[ity categories and the two motivations for walking （recreation and transportation）. To our knowledge, this is the first study that reports links between wa[kability and walking for recreation. Additionally, the use of the Walkability Framework allowed us to identify the walkability categories most strongly correlated with the two motivations for walking. The results of this study support the use of the Walkability Framework as a model to measure the built environment in relation to its ability to promote physical activity.

关键词： Watkability Physical activity Buitt environment LEED-ND Neighborhood design

Radiofrequency electric-field heating behaviors of highly enriched semiconducting and metallic single-walled carbon nanotubes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2015年第9期8卷 2859-2870页

作者： Stuart j. Corr Mustafa Raoof Brandon T. Cisneros Alvin W. Orbaek Matthew A. Cheney j.stin j. Law Nadia C. Lara Andrew R. barron Lon j. Wilsor Steven A. Curley Division of Surgery Baylor College of Medicine Houston TX 77030 USA Department of Surgical Oncology University of Texas M.D. Anderson Cancer Center Houston TX 77030 USA Department of Chemistry and the Richard E. Smalley Institute for Nanoscale Science and Technology Rice University Houston TX 77005 USA Department of Surgery The University of Arizona College of Medicine Tucson AZ 85724 USA Department of Chemistry and Biochemistry University of California San Diego La Jolla CA 92093 USA College of Engineering Swansea University Singleton Park Swansea SA2 8PP Wales UK Department of Mechanical Engineering and Materials Science Rice University Houston TX 77005 USA

It is theorized that enhanced thermal heating may result from exposing single-walled carbon nanotubes （SWNTs） embedded in a conductive host to radiofrequency （RF） electric fields. We examine the RF-induced （13.56 MHz） heating behaviors of 95% metallic- and semiconducting-enriched SWNTs （m-/s-SWNTs） suspended in aqueous solutions with varying NaC1 molarity （0.001 mM-1 M）. The heating effects were only evident for host molarities below 1 mM （equivalent to 0.1 S/m） at which the s-SWNT heating rates dominated those of the m-SWNTs. The heating effects were localized to aligned and aggregated ＂SWNT ropes＂ -1 cm in length that formed in suspension, parallel to the electric-field vector, during the RF exposure. For molarities above 1 mM, no enhancements were evident, owing to the large heating effects of the bulk ionic NaC1 suspensions, which were observed in previous studies. Although larger enhancement effects proportional to the host conductivity have been theoretically predicted for m-/s-SWNT suspensions, this was not observed most likely because of the aggregation and screening effects, which diminished the scattered electric field near the m-/s-SWNTs. Our research may further the development of better nanoparticle heating agents for applications such as non-invasive RF-induced cancer hyperthermia.

关键词： rad.iofrequency,carbon nanotubes,metallic,semiconducting,hyperthermia

Effect of inductively coupled plasma surface treatment on silica gel and mesoporous MCM-41 particles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2018年第6期20卷 104-113页

作者： j.A j.AREZ-MORENO U CHACON-ARGAEZ j.barron-ZAMBRANO C CARRERA-FIGUEIRAS P QUINTANA-OWEN W TALAVERA-PECH Y PEREZ-PADILLA A AVILA-ORTEGA facultad de ingeniería química-uady periférico norte kilómetro 33.5col.chuburna de hidalgo inn C.P. 97203 Mérida Yucatan México centro de investigación y de estudios avanzados del ipn-unidad mérida km.6 antigua carretera a progreso apdo. Postal 73 Cordemex 97310 Méfida Yucatán México

Silica gel and MCM-41 synthesized mesoporous materials were treated with either oxygen（O_2）,hexamethyldisiloxane（HMDSO） and organic vapors like ethanol（Et OH）,and acrylonitrile（AN）inductive *** radiofrequency power for the modification was fixed to 120 W and30 min,assuring a high degree of organic ionization energy in the *** surface properties were studied by infrared spectroscopy（FTIR）,scanning electron microscopy,x-ray photoelectron spectroscopy and dynamic light scattering technique was used for characterizing size *** the silica and MCM-41 particles were modified by AN and HMDSO plasma gases,the surface morphology of the particles was changed,presenting another color,size or *** contrast,the treatments of oxygen and Et OH did not affect the surface morphology of both particles,but increased the oxygen content at the surface bigger than the AN and HMDSO plasma *** this study,we investigated the influence of different plasma treatments on changes in morphology and the chemical composition of the modified particles which render them a possible new adsorbent for utilization in sorptive extraction techniques for polar compounds.

关键词： silica MCM-41 nanoparticles plasma treatment

The initial stages of Li_(2)O_(2) formation during oxygen reduction reaction in Li-O_(2) batteries:The significance of Li_(2)O_(2) in charge-transfer reactions within devices

在线全文

学校读者我要写书评

暂无评论

j.urnal of Energy Chemistry 2024年第1期88卷 223-231,I0006页

作者： Daniela M.j.sepetti Bianca P.Sousa Simone A.j.Rodrigues Renato G.Freitas Gustavo Doubek Advanced Energy Storage Division LABCenter for Innovation on New EnergiesSchool of Chemical EngineeringUniversity of CampinasAv Albert Einstein 50013083-852CampinasSPBrazil Institute of Physics&Department of Chemistry Laboratory of Computational MaterialsFederal University of Mato Grosso78060-900CuiabáMTBrazil

Lithium-oxygen batteries are a promising technology because they can greatly surpass the energy density of lithium-ion ***,this theoretical characteristic has not yet been converted into a real device with high *** with air contamination,metallic lithium reactivity,and complex discharge and charge reactions are the main issues for this technology.A fast and reversible oxygen reduction reaction(orr)is crucial for good performance of secondary batteries',but the partial knowledge of its mechanisms,especially when devices are concerned,hinders further *** this perspective,the present work uses operando Raman experiments and electrochemical impedance spectroscopy(EIS)to assess the first stages of the discharge processes in porous carbon electrodes,following their changes cycle by cycle at initial operation.A growth kinetic formation of the discharge product signal(Li_(2)O_(2))was observed with operando Raman,indicating a first-order reaction and enabling an analysis by a microkinetic *** solution mechanism in the evaluated system was ascribed for an equivalent circuit with three time *** the time constant for the anode interface reveals to remain relatively constant after the first discharge,its surface seemed to be more *** model indicated that the reaction occurs at the Li_(2)O_(2) surface,decreasing the associated resistance during the initial discharge ***,the growth of Li_(2)O_(2) forms a hetero-phase between Li_(2)O_(2)/electrolyte,while creating a more compact and homogeneous on the Li_(2)O_(2)/cathode *** methodology here described thus offers a way of directly probing changes in surface chemistry evolution during cycling from a device through EIS analysis.

关键词： Li-O_(2)battery Operando Raman analysis Equivalent circuit modeling Time-constant distribution

3rd ANtarctic Gravity Wave Instrument Network(ANGWIN)Science Workshop

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2017年第1期34卷 1-3页

作者： Tracy MOFFAT-GRIFFIN Mike j.TAYLOR Takuj. NAKAMURA Andrew j.KAVANAGH j.Scott HOSKING Andrew orr Britsh Antarctic survey High CrossCambridge CB30ETUK Utah State University LoganUT84322USA National Institute of Polar Research Tachikawa-shiTokyo 190-8518Japan

1. Overview The 3rd ANtarctic Gravity Wave Instrument Network （ANGWIN） science workshop was held on 12-14 April 2016 in Cambridge, UK. ANGWIN is a highly successful grassroots program that was started in 2011 （in the Cornish English dialect ANGWIN means ＂the white＂）. Although ini- tially focused on the Antarctic, we now aim to develop collaborations in both polar regions.

关键词： ANGWIN)Science Workshop Wave

Models to predict inj.ry, physical fitness failure and attrition in recruit training: a retrospective cohort study

在线全文

学校读者我要写书评

暂无评论

Military Medical Research 2020年第4期7卷 391-400页

作者： Robin M.orr Bruce S.Cohen Stephen C.Allison Lakmini Bulathsinhala Edward j.Zambraski Mark j.ffrey Tactical Research Unit Bond University2 Promethean WayGold CoastRobinaQLD 4226Australia United States Army Research Institute for Environmental Medicine NatickMA 01760USA Defence Science and Technology Group Port MelbourneVIC 3207Australia

Background:Attrition rate in new army recruits is higher than in incumbent *** the current study,we identified the risk factors for attrition due to inj.ries and physical fitness failure in recruit training.A variety of predictive models were ***:This retrospective cohort included 19,769 Army soldiers of the Australian Defence Force receiving recruit training during a period from 2006 to *** them,7692 reserve soldiers received a 28-day training course,and the remaining 12,077 full-time soldiers received an 80-day training *** data included anthropometric measures,course-specific variables,inj.ry,and physical fitness *** regression was used to develop a variety of models to predict the rate of attrition due to inj.ries and physical fitness *** area under the receiver operating characteristic curve was used to compare the performance of the ***:In the overall analysis that included both the 28-day and 80-day courses,the incidence of inj.ry of any type was 27.8%.The 80-day course had a higher rate of inj.ry if calculated per course(34.3%vs.17.6%in the 28-day course),but lower number of inj.ries per person-year(1.56 vs.2.29).Fitness test failure rate was significantly higher in the 28-day course(30.0%vs.12.1%).The overall attrition rate was 5.2%and 5.0%in the 28-day and 80-day courses,*** fracture was common in the 80-day course(n=44)and rare in the 28-day course(n=1).The areas under the receiver operating characteristic curves for the course-specific predictive models were relatively low(ranging from 0.51 to 0.69),consistent with"failed"to"poor"predictive *** course-combined models performed somewhat better than the course-specific models,with two models having AUC of 0.70 and 0.78,which are considered"fair"predictive ***:Attrition rate was similar between 28-day and 80-day *** comparison to the 80-day full course,the 28-day course had a lower rat

关键词： Military training Predictive modelling Risk management Soldier

Superchiral near fields detect virus structure

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2020年第1期9卷 103-112页

作者： Tarun Kakkar Chantal Keij.er Marion Rodier Tatyana Bukharova Michael Taliansky Andrew j.Love j.el j.Milner Affar S.Karimullah Laurence D.barron Nikolaj.Gadegaard Adrian j.Lapthorn Malcolm Kadodwala School of Chemistry Joseph Black BuildingUniversity of GlasgowGlasgow G128QQUK Institute of Molecular Cell and Systems Biology and School of Life SciencesUniversity of GlasgowG128QQ GlasgowUK j.mes Hutton Inst Cell&Mol SciDundee DD25DAUK Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS Moscow 117997Russia School of Engineering Rankine BuildingUniversity of GlasgowGlasgow G128LTUK

Optical spectroscopy can be used to quickly characterise the structural properties of individual ***,it cannot be applied to biological assemblies because light is generally blind to the spatial distribution of the component *** insensitivity arises from the mismatch in length scales between the assemblies(a few tens of nm)and the wavelength of light required to excite chromophores(≥150 nm).Consequently,with conventional spectroscopy,ordered assemblies,such as the icosahedral capsids of viruses,appear to be indistinguishable isotropic spherical *** limits potential routes to rapid high-throughput portable detection appropriate for point-of-care ***,we demonstrate that chiral electromagnetic(EM)near fields,which have both enhanced chiral asymmetry(referred to as superchirality)and subwavelength spatial localisation(∼10 nm),can detect the icosahedral structure of virus ***,they can detect both the presence and relative orientation of a bound virus *** illustrate the potential uses of the exquisite structural sensitivity of subwavelength superchiral fields,we have used them to successfully detect virus particles in the complex milieu of blood serum.

关键词： chiral detect fields

Small-Scale Spatial Patterns of <i>Copernicia alba</i>Morong near Bahia Negra, Paraguay

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Natural Resources 2013年第5期4卷 369-377页

作者： Michelle E. Cisz Michael j. Falkowski Blair orr School of Forest Resources and Environmental Science Michigan Technological University Houghton USA

We assessed the spatial distribution of Copernicia alba Morong. In the study area, a lowland palm savanna floodplain, C. alba is the only overstory species. We hypothesized C. alba would be randomly distributed within natural stands. Palms were tallied in six randomly located 0.25 haplots and analyzed using a first-order, Ripley’s K function to assess the distribution of j.venile, adult, and total palm populations. While the total population had either aggregated or random distributions, when analyzing j.venile and adult population separately, we found j.veniles were consistently more aggregated than the adults.

关键词： Ripley’s K-Function First Order Analysis Floodplain Fire Chaco Monotypic Stands Disturbance Ecol-ogy Population Dynamics

Numerical Simulation of a Batch-Type Reheating Furnace

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World j.urnal of Engineering and Technology 2018年第4期6卷 713-722页

作者： Francisco j. Nava Miguel A. barron Dulce Y. Medina Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Ciudad de Mexico Mexico

A numerical analysis of a batch-type reheating furnace with and without thermal load was carried out using the Computational Fluid Dynamics technique. The furnace has two premixed burners and methane is used as fuel. Previous to the numerical experiments, a mesh convergence test was carried out and the average internal furnace temperature and the exhaust gases temperature were monitored as function of the number of cells in the discretized system. The influence of the Air/Fuel ratio, the position of the burners, and the thermal load on the average internal temperature, the exhaust gases temperature, and the molar fraction of methane and oxygen in the exhaust gases was numerically explored.

关键词： Air/Fuel Ratio CFD Simulation Exhaust Gas Numerical Simulation Premixed Burner Reheating Furnace Thermal Load