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Drone systems for delivering defibrillators for sudden cardiac arrests

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Journal of Acute Disease 2024年第1期13卷 1-2页

作者： Thirumurugan e edwin Dias Karthick R Srinivas University MangaloreKarnatakaIndia Faculty of Allied Health Science DR MGR Educational and Research InstituteACS Medical CollegeChennaiTamil NaduIndia

Unmanned aerial vehicles(UAVs),or drones,that were initially developed for military use during World War i[1],have evolved into highly sophisticated aircraft that can be navigated remotely using global positioning *** constant improvements,drones have become more efficient,and cost-effective,with longer battery life and greater loading ***,UAVs have proven to be an effective and affordable solution for enhancing healthcare accessibility for patients who face geographical or infrastructural *** drone networks can greatly reduce the time transporting life-saving equipment,such as delivering automated external defibrillators(AeDs),to cardiac arrest victims,and can provide quick assistance to reduce travel time for the patients.

关键词： initially travel battery

Flow-Field of an Axisymmetric Lobed Mixer

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Journal of Thermal Science 2004年第1期13卷 40-45页

作者： i.Yimer S.Manipurath i.Campbell W.e.Carscallen Gas Turbine environmental Research Centre Aerodynamics LabInstitute for Aerospace ResearchNational Research Council Canada1200 Montreal RoadOttawaOntarioCanadaK1A 0R6

The flow-field of a fuel/air mixing system with an axisymmetric lobed mixer was numerically investigated. Large-scale streamwise vortices are formed immediately downstream of the mixer trailing edge, stretched further downstream, and finally broken into fragments where more intense mixing occurs. Both numerical and experimental results indicate that the length required for streamwise vortices breakdown in the confined flow-field of an axisymmetric lobed mixer is much shorter than that in the case of planar lobed mixers subject to parallel freestreams. For the conditions studied, the streamwise vortices start to breakdown at three wavelengths downstream of the mixer trailing edge.

关键词： axisymmetric lobed mixer confined flow fuel/air mixing

Aspect of the specialty metals potentials of pegmatites in western Oban Massif,Se Nigeria:A preliminary geochemical approach

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Chinese Journal Of Geochemistry 2012年第4期31卷 355-361页

作者： Oden M.i. igonor e.e. Department of Geology University of CalabarP.M.B.1115 CalabarNigeria Petra Prospectors Limited Nigeria

Minerals in general and rare-metals in particular are of invaluable importance in the development and industrialization of any *** is true as they could affect a nation's national income,employment ratio,Gross National Product,and its entire *** study area(western Oban Massif-Se Nigeria) was investigated for its specialty metals bearing potentials because of(1) its geology,which is similar to other specialty metals bearing areas of the world;(2) past works,which points to the area as a likely source of economic deposit of such metals;and(3) the soaring cost of these rare metals in the light of recent upsurge in global information/telecommunication *** from the study,show that only cesium(Cs) and beryllium(Be) show minute signs or indications of enrichment if properly *** these metals should be studied in details to ascertain their economic *** rocks are too deficient in the other rare-metals(lithium,zirconium,strontium,tantalite,niobium,tungsten,gallium,and chromium) to warrant further analysis.

关键词：特种金属尼日利亚地球化学方法电位伟晶岩稀有金属矿地块国民生产总值

Hydrogen transport in metals: integration of permeation, thermal desorption and degassing

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Journal of Materials Science & Technology 2017年第12期33卷 1433-1447页

作者： e.i.Galindo-Nava B.i.Y.Basha P.e.J.Rivera-Díaz-del-Castillo Department of Materials Science and Metallurgy University of Cambridge Department of engineering Lancaster University

A modelling suite for hydrogen transport during electrochemical permeation, degassing and thermal desorption spectroscopy is presented. The approach is based on Fick＇s diffusion laws, where the initial concentration and diffusion coefficients depend on microstructure and charging conditions. The evolution equations are shown to reduce to classical models for hydrogen diffusion and thermal desorption spectroscopy. The number density of trapping sites is found to be proportional to the mean spacing of each microstructural feature, including dislocations, grain boundaries and various precipitates. The model is validated with several steel grades and polycrystalline nickel for a wide range of processing conditions and microstructures. A systematic study of the factors affecting hydrogen mobility in martensitic steels showed that dislocations control the effective diffusion coefficient of hydrogen. However,they also release hydrogen into the lattice more rapidly than other kind of traps. it is suggested that these effects contribute to the increased susceptibility to hydrogen embrittlement in martensitic and other high-strength steels. These results show that the methodology can be employed as a tool for alloy and process design, and that dislocation kinematics play a crucial role in such design.

关键词： Hydrogen Diffusion Modelling Trapping Permeation Desorption

A Novel Contactless Method for Characterization of Semiconductors：Surface electron Bean induced Voltage in Scanning electron Microscopy

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Chinese Physics Letters 2002年第9期19卷 1329-1332页

作者：朱世秋 e.i.RAU 等 NationalLaboratoryforSuperlatticesandMicrostructures InstituteofSemiconductorsChineseAcademyofSciencesBeijing100083 DepartmentofPhysics MoscowStateUniversityMoscow119899Russia

We present a novel contactless and nondestructive method called the surface electron beam induced voltage (SeBiV) method for characterizing semiconductor materials and devices. The SeBiV method is based on the detection of the surface potential induced by electron beams of scanning electron microscopy (SeM). The core part of the SeBiV detection set-up is a circular metal detector placed above the sample surface. The capacitance between the circular detector and whole surface of the sample is estimated to be about 0.64pf. it is large enough for the detection of the induced surface potential. The irradiation mode of electron beam (e-beam) influences the signal generation. When the e-beam irradiates on the surface of semiconductors continuously, a differential signal is obtained. The real distribution of surface potentials can be obtained when a pulsed e-beam with a fixed frequency is used for irradiation and a lock-in amplifier is employed for detection. The polarity of induced potential depends on the structure of potential barriers and surface states of samples. The contrast of SeBiV images in SeM changes with irradiation time and e-beam intensity.

关键词： Scanning electron microscopy

impact excitations of Hydrogen Atoms in Collisions with Protons and Antiprotons

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Chinese Physics Letters 2014年第8期31卷 53-57页

作者： RedaS.Tantawi T.e.i.Nassar MathematicsDepartment FacultyofScienceZagazigUniversityZagazigEgypt BasicScienceDepartment HigherTechnologicalInstituteTenthofRamadaCityEgypt

The direct impact excitations of ground-state hydrogen atoms by protons and antiprotons are investigated by using an impact parameter treatment. The calculations are performed within the solution of the coupled differential equations arising from the one-center atomic-orbital close-coupling approach as well as the impact parameter version of the first and second Born approximations. We have considered calculations that allow couplings to the n=1-5 states （up to g sub-levels） of the target atom as well as others, which neglect the effect of all states other than the initial and final states of the target atom. The sensitivity of the cross sections to the charge of the projectile is studied. The calculated cross sections are compared with those obtained by previous theoretical and experimental results.

关键词： Ground state

enabling low-cost decentralized power reserves adopting carbon dioxide for green methane exchange in stabilized clathrate adsorbent

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Journal of energy Chemistry 2024年第10期97卷 438-443,I0009页

作者： Lucas Hanssens Maarten Houlleberghs C.Vinod Chandran Geert Watson Sambhu Radhakrishnan Pascal Van Der Voort Joeri F.M.Denayer Christine e.A.Kirschhock Johan A.Martens eric Breynaert Centre for Surface Chemistry and Catalysis-Characterization and Application Team(COK-KAT) 3001 LeuvenBelgium NMR/X-Ray Platform for Convergence Research(NMRCoRe) 3001 LeuvenBelgium Centre for Ordered Materials Organometallics and Catalysis(COMOC)Department of ChemistryGhent University9000 GhentBelgium Department of Chemical engineering Vrije Universiteit Brussel1050 BrusselBelgium

*** circular methane energy systems in recent decades,methane-based energy systems have rapidly gained traction across the globe because of the increasing availability of low-cost methane production ***,fossil methane... 详细信息

关键词： Long duration energy storage Green methane Carbon neutrality Confined clathrate hydrates CH_(4)/CO_(2) exchange Direct gas exchange

environmental exposure as a risk-modifying factor in liver diseases:Knowns and unknowns

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Acta Pharmaceutica Sinica B 2021年第12期11卷 3768-3778页

作者： Juliane i.Beier Gavin e.Arteel Department of Medicine Division of GastroenterologyHepatology and NutritionUniversity of PittsburghPittsburghPA 15213USA Pittsburgh Liver Research Center and University of Pittsburgh PittsburghPA 15213USA Department of environmental and Occupational Health University of PittsburghPA 15213USA

Liver diseases are considered to predominantly possess an inherited or xenobiotic ***,inheritance drives the ability to appropriately adapt to environmental stressors,and disease is the culmination of a maladaptive *** "pure" genetic and "pure" xenobiotic liver diseases are modified by each other and other factors,identified or *** purpose of this review is to highlight the knowledgebase of environmental exposure as a potential risk modifying agent for the development of liver disease by other *** exercise is not to argue that all liver diseases have an environmental component,but to challenge the assumption that the current state of our knowledge is sufficient in all cases to conclusively dismiss this as a *** review also discusses key new tools and approaches that will likely be critical to address this question in the *** together,identifying the key gaps in our understanding is critical for the field to move forward,or at the very least to "know what we don't know."

关键词： Hepatic injury exposomics Liver disease Drug-induced liver injury Alcoholic liver disease Non-alcoholic liver disease inherited liver disease Autoimmune liver disease

expanded Porphyrin exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium

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CCS Chemistry 2024年第7期6卷 1731-1738页

作者： Dmitry i.Nazarov Jorge Labella Alexey V.Kuzmin Maxim A.Faraonov evgenii N.ivanov Salavat S.Khasanov Tomas Torres Mikhail K.islyaikin Dmitri V.Konarev Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAS 142432 Chernogolovka Department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid institute of Solid-State Physics RAS 142432 Chernogolovka Research institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.Krestov institute of Solution Chemistry of the Russian Academy of Sciences 153045 Ivanovo institute for Advanced Research in Chemical Sciences Universidad Autonoma de Madrid28049 Madrid iMDeA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of Dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism