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Characterization of a 3-Phase a.c. Free Burning Arc Plasma

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Plasma Science and Technology 2006年第2期8卷 156-163页

作者：夏维东 Laurent FULCHERI Jose GONZALEZ-AGUILAR 李辉 thomas m. GRUENBERGER University of Science" and Technology of China Hefei 230027 China. Centre for Energy Studies Ecole des Mines de Paris Rue Claude Daunesse F-06904 Sophia Antipolis France University of Science and Technology of China Hefei 230027 China.

A 3-phase a.c. arc plasma reactor with large volume plasma has been developed for the synthesis of new carbon nano-structures. One of the main characteristics of the plasma system is related to the absence of a fixed neutral point. This gives rise to a rich and complex phenomenology related to instabilities and arc motion since the arcs are ＂burning＂ freely in the gas flow between the three electrodes. This paper is dedicated to the analysis of the behavior of such a system under typical conditions using argon and nitrogen as plasma gases. A classification of are configuration, arc commutating, arc interaction, arc motion and arc instabilities are discussed based on ultra high-speed cine camera analysis. A simple model describing the time evolution of the system is also presented and compared with the experimental measurements. The results show that an adequate control could allow the improvement of the overall system.

关键词： 3-phase AC arc plasma free arc arc motion arc commutating arc instabilities

Study of Thermal Reactivity and Kinetics of HmX and Its PBX by Different methods

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火炸药学报 2017年第2期40卷 24-32页

作者： mohamed Abd-Elghany thomas m.klapotke Ahmed Elbeih Saeed Hassanein Tamer Elshenawy Department Chemie Ludwig-Maximilians Universitat Munchen 81377 Munchen Germany military Technical College Kobry Elkobbah Cairo Egypt Technical Research Center Cairo Egypt

Vacuum Stability Test(VST)was used to determine the thermal behavior and kinetic parameters of 1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HmX)and its mixture with hydroxyl-terminated polybutadiene(HTPB)as a binder coded as HmX/*** fitting and isoconversional method were applied to determine the kinetic parameters based on VST *** comparison,non-isothermal thermogravimetry analysis data(TGA)was also used to calculate the kinetic parameters by using Kissinger,OFW(Ozawa,Flynn,and Wall)and KAS(Kissinger-Akahira-Sunose)*** Kinetics and Technology Solution(AKTS)software was also used to determine the decomposition kinetics of the studied *** Scanning Calorimetry(DSC)was employed to determine the decomposition heat flow properties of the studied *** show that the activation energies obtained using VST results is 360.1kJ/mol for pure HmX and 186.9kJ/mol for HmX/*** activation energies obtained by the three different methods using TGA results are in the range of 360-368kJ/mol for pure HmX and 190-206kJ/mol for HmX/*** is concluded that values of kinetic parameters obtained by VST are close to that obtained by the different techniques using TG/DTG *** onset decomposition peak of HmX/HTPB is lower than that of HmX where the HTPB binder has negative effect on the thermal stability of *** results of all the applied techniques prove that HmX/HTPB has lower activation energy and heat release than the pure *** polymeric matrix has negative effect on the kinetic parameters of HmX.

关键词： HmX HmX/HTPB 火炸药质量管理研究工作 PBX

S. E. m. analysis of quartz sand grains from selected Hong Kong and Chinese littoral environments

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Acta Oceanologica Sinica 1989年第3期8卷 409-422页

作者： A.T.Williams m.C.thomas Coastal Research Unit Department of Science and Chemical Engineering.the Polytechnic of WalesPontypriddMid GlamorganCF37 IDL.UKCoastal Research UnitDepartment of Science and Chemical Engineering.the Polytechnic of WalesPontypriddMid GlamorganCF37 IDL.UK

This pilot study attempts to demonstrate some underlying scanning electron microscopy themes of quartz grain surface textures. A variety of textural patterns and individual features are described for grains selected from various littoral environments. An attempt was made to differentiate samples on surface textures alone, but limitations of using this technique in sedimentological isolation were apparent. Statistical analysis of checklist data and photographic evidence revealed some of the more important feature combinations used in environmental diagnosis. The use of discriminant analysis provided quantitative sample separation.

关键词： In analysis of quartz sand grains from selected Hong Kong and Chinese littoral environments

Efficient light harvesting from flexible perovskite solar cells under indoor white light-emitting diode illumination

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Nano Research 2017年第6期10卷 2130-2145页

作者： Giulia Lucarelli Francesco Di Giacomo Valerio Zardetto mariadriana creatore thomas m. Brown Centre for Hybrid and Organic Solar Energy (CHOSE) Department of Electronic Engineering University of Rome Tor Vergata Via del Politecnico 100133 Rome Italy Hoist Centre/TNO - Solliance 5655AE Eindhoven the Netherlands Department of Applied Physics Eindhoven University of Technology P.O. Box 513 5600 MB Eindhoven the Netherlands

This is the first report of an investigation on flexible perovskite solar cells for artificial light harvesting by using a white light-emitting diode （LED） lamp as a light source at 200 and 400 Ix, values typically found in indoor environments. Flexible cells were developed using either low-temperature sol-gel or atomic- layer-deposited compact layers over conducting polyethylene terephthalate （PET） substrates, together with ultraviolet （UV）-irradiated nanoparticle TiO2 scaffolds, a CH3NHBPbI3xClx perovskite semiconductor, and a spiro-meOTAD hole transport layer. By guaranteeing high-quality carrier blocking （via the 10-40 nm-thick com- pact layer） and injection （via the nanocrystalline scaffold and perovskite layers） behavior, maximum power conversion efficiencies （PCE） and power densities of 10.8% and 7.2 pW-cm-2, respectively, at 200 lx, and 12.1% and 16.0 -tW＇cm-2, respectively, at 400 lx were achieved. These values are the state-of-the-art, comparable to and even exceeding those of flexible dye-sensitized solar cells under LED lighting, and significantly greater than those for flexible amorphous silicon, which are currently the main flexible photovoltaic technologies commercially considered for indoor applications. Furthermore, there are significant margins of improvement for reaching the best levels of efficiency for rigid glass-based counterparts, which we found was a high of PCE -24% at 400 lx. With respect to rigid devices, flexibility brings the advantages of being low cost, lightweight, very thin, and COlfformal, which is especially important for seamless integration in indoor environments.

关键词： flexible perovskite solar cells indoor light harvesting atomic layer deposition nanocrystalline scaffolds flexible photovoltaics energy harvesting

Geochronological constraints on the metamorphic sole of the Semail ophiolite in the United Arab Emirates

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Geoscience Frontiers 2016年第4期7卷 609-619页

作者： Nick m.W.Roberts Robert J.thomas Joachim Jacobs NERC Isotope Geosciences Laboratory British Geological SurveyKeyworthNG12 5GGUK Council for Geoscience P.O.Box 572Bellville 7535South Africa University of Bergen.Department of Earth Science PB 78035020 BergenNorway Norwegian Polar Institute Fram Centre9296 TromsoNorway

The Semail ophiolite of Oman and the United Arab Emirates （UAE） provides the best preserved large slice of oceanic lithosphere exposed on the continental crust, and offers unique opportunities to study processes of ocean crust formation, subduction initiation and obduction. metamorphic rocks exposed in the eastern UAE have traditionally been interpreted as a metamorphic sole to the Semail ophiolite. However, there has been some debate over the possibility that the exposures contain components of older Arabian continental crust. To help answer this question, presented here are new zircon and futile U-Pb geochronological data from various units of the metamorphic rocks. Zircon was absent in most samples. Those that yielded zircon and futile provide dominant single age populations that are 95-93 ma, partially overlapping with the known age of oceanic crust formation （96.5-94.5 ma）, and partially overlapping with cooling ages of the metamorphic rocks （95 90 ma）. The data are interpreted as dating high-grade metamorphism during subduction burial of the sediments into hot mantle lithosphere, and rapid cooling during their subsequent exhumation. A few discordant zircon ages, interpreted as late Neoproterozoic and younger, represent minor detrital input from the continent. No evidence is found in favour of the existence of older Arabian continental crust within the metamorphic rocks of the UAE.

关键词： Semail ophiolite United Arab Emirates metamorphic sole U-Pb geochronology Zircon Rutile

Wireless data management system for environmental monitoring in livestock buildings

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Information Processing in Agriculture 2017年第1期4卷 1-17页

作者： James Gray thomas m.Banhazi Alexander A.Kist Faculty of Health Engineering and SciencesUniversity of Southern Queensland(USQ)West StreetToowoombaQLD 4350Australia National Centre for Engineering in Agriculture(NCEA) University of Southern Queensland(USQ)West StreetToowoombaQLD 4350Australia

The impact of air quality on the health,welfare and productivity of livestock needs to be considered,especially when livestock are kept in enclosed *** monitoring of such environmental factors allows for the development of appropriate strategies to reduce detrimental effects of sub-optimal air quality on the respiratory health of both livestock and *** 2009,an environmental monitoring system was designed,developed and tested that allowed for the monitoring of a number of airborne *** limitation of the system was the manual collection of logged data from each *** paper identifies limitations of the current environmental monitoring system and suggests a range of networking technologies that can be used to increase *** is taken for the networking of environmental monitoring units,as well as the collection of recorded ***,the design and development of a software system that is used to collate and store recorded environmental data from multiple farms is *** order to design such a system,simplified software engineering processes and methodologies have been *** main steps taken in order to complete the project were requirements elicitation with clients,requirements analysis,system design,implementation and finally *** outcome of the project provided a potential prototype for improving the environmental monitoring system and analysis informing the benefit of the implementation.

关键词： Sensors Environmental monitoring Networking Software engineering

Time for a paradigm shift in the classification of muscle injuries

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Journal of Sport and Health Science 2017年第3期6卷 255-261页

作者： Bruce Hamilton Juan-manuel Alonso thomas m.Best High Performance Sport New Zealand Millennium Institute of Sport and HealthMairangi BayAuckland 0110New Zealand Sports medicine Department Qatar Orthopaedic and Sports Medicine HospitalDoha 22922Qatar UHealth Sports medicine Institute University of Miami Miller School of MedicineMiamiFL 33136USA

muscle injuries remain one of the most common injuries in sport,yet despite this,there is little consensus on how to either effectively describe or determine the prognosis of a specific muscle *** approaches to muscle classification and grading of medicine have been applied over the last century,but over the last decade the limitations of historic approaches have been *** a consequence,in the past 10 years,clinical research groups have begun to question the historic approaches and reconsider the way muscle injuries are classified and *** a narrative approach,this manuscript describes several of the most recent attempts to classify and grade muscle injuries and highlights the relative strengths and weaknesses of each *** each of the new classification and grading systems have strengths,there remains little consensus on a system that is both comprehensive and evidence *** of the currently identified features within the grading systems have relevance to accurately determining prognosis.

关键词： Classification Grading magnetic resonance imaging muscle injury Return to play Ultrasound

Dairy sheep production research at the University of Wisconsin-madison,USA-a review

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Journal of Animal Science and Biotechnology 2014年第2期5卷 127-138页

作者： David L thomas Yves m Berger Brett C mcKusick Claire m mikolayunas University of Wisconsin-madison Department of Animal Sciences Spooner Agricultural Research Station Current address:merial Ltd midwest Organic Services Association ViroquaWisconsinUSA

Commercial milking of sheep is a new agricultural industry in the United States starting approximately 30 yr ago. The industry is still small, but it is growing. The majority of the sheep milk is used in the production of specialty cheeses. The United States is the major importer of sheep milk cheeses with 50 to 60% of annual world exports coming to the United States during the past 20 yr. Therefore, there is considerable growth potential for the industry in the United States. The only dairy sheep research flock in North America is located at the Spooner Agricultural Research Station of the University of Wisconsin-madison. The research program started in 1993 and has been multifaceted; dealing with several areas important to commercial dairy sheep farmers. The East Friesian and Lacaune dairy breeds were compared and introduced to the industry through the research program. Both dairy breeds produced significantly more milk than traditional meat-wool breeds found in the U.S., but the two breeds differed in their production traits. East Friesian-cross ewes produced more lambs and slightly more milk than Lacaune-cross ewes whereas Lacaune-cross ewes produced milk with a higher percentage of fat and protein than East Friesian-cross ewes. Lactation physiology studies have shown that ewes with active corpora lutea have increased milk yields, oxytocin release during milking is required to obtain normal fat percentages in the milk, large udder cisterns of dairy ewes can allow for increased milking intervals, and short daylengths during late pregnancy results in increased milk yield. In the nutrition area, legume-grass pastures and forages with a higher percentage of legume will result in increased milk production. Grazing ewes respond to additional supplementation with increased milk yield, but it is important to match the supplement to the quality of the grazing. Ewes on high quality legume-grass pastures that are high in rumen degradable protein respond with increased milk

关键词： Dairy sheep East Friesian Grazing Lacaune Lactation physiology Nitrogen efficiency RDP RUP Supplementation

Lattice distortion releasing local surface strain on high-entropy alloys

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Nano Research 2022年第6期15卷 4775-4779页

作者： Christian m.Clausen Jack K.Pedersen thomas A.A.Batchelor Jan Rossmeisl Department of Chemistry University of Copenhagen2100 KøbenhavnØDenmark

High-entropy alloys(HEAs)have the potential to be a paradigm-shift for rational catalyst discovery but this new type of alloy requires a completely new approach to predict the surface *** addition to the ligand effect perturbing the surface–adsorbate bond,the random configuration of elements in the surface will also induce local strain effects due to the varying radii of neighboring *** modelling of HEA surface reactivity requires an estimate of this effect:To what degree is the adsorption of intermediates on these lattice distorted atomic environments affected by local strain?In this study,more than 3,500 density functional theory(DFT)calculated adsorption energies of*OH and*O adsorbed on the HEAs IrPdPtRhRu and AgAuCuPdPt are statistically analyzed with respect to the lattice constants of the alloys and the surfaces of each individual binding *** is found that the inherent distortion of the lattice structure in HEAs releases the local strain effect on the adsorption energy as the atomic environment surrounding the binding atom(s)settles into a relaxed *** is even observed to be true for clusters of atoms of which the sizes deviate significantly from the atomic environment in which they are *** elucidates an important aspect of binding site interaction with the neighboring atoms and thus constitutes a step towards a more accurate theoretical model of estimating the reactivity of HEA surfaces.

关键词： high-entropy alloys surface reactivity strain effect surface strain electrocatalysis oxygen reduction reaction