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Wettability,reactivity,and interface structure in Mg/Ni system

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journal of Magnesium and Alloys 2024年第2期12卷 659-672页

作者： S.Terlicka N.Sobczak Ł.Maj P.Darłak j.j.Sobczak Institute of Metallurgy and Materials Science Polish Academy of Sciences25 Reymonta Str.KrakowPoland Faculty of Foundry Engineering AGH University23 Reymonta Str.KrakowPoland

The sessile drop method was applied to the experimental investigation of the wetting and spreading behaviors of liquid Mg drops on pure Ni *** comparison,the experiments were performed in two variants:(1)using the Capillary Purification(CP)procedure,which allows the non-contact heating and squeezing of a pure oxide-free Mg drop;(2)by classical Contact Heating(CH)*** high-temperature tests were performed under isothermal conditions(CP:760℃for 30 s;CH:715℃for 300 s)using Ar+5 wt%H_(2) *** the sessile drop tests,images of the Mg/Ni couples were recorded by CCD cameras(57 fps),which were then applied to calculate the contact angles of metal/substrate *** and transmission electron microscopy analyses,both coupled with energy-dispersive X-ray spectroscopy,were used for detailed structural characterization of the solidified *** was found that an oxide-free Mg drop obtained by the CP procedure showed a wetting phenomenon on the Ni substrate(an average contact angleθreading and good wetting over the Ni substrate(θ_((CP))~20°in 5 s)to form a final contact angle ofθ_(f(CP))~18°.In contrast,a different wetting behavior was observed for the CH procedure,where the unavoidable primary oxide film on the Mg surface blocked the spreading of liquid Mg showing apparently non-wetting behavior after 300 s contact at the test ***,in both cases,the deep craters formed in the Ni substrates under the Mg drops and significant change in the structure of initially pure Mg drops to Mg-Ni alloys suggest a strong dissolution of Ni in liquid Mg and apparent values of the final contact angles measured for the Mg/Ni system.

关键词： Magnesium-based alloys Sessile drop tests Capillary purification procedure Wettability reactivity Contact angle

Music alters heart rate and psychological responses but not muscle activation during light-intensity isometric exercise

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Sports Medicine and Health Science 2024年第4期6卷 394-401页

作者： Andrew r.Moore jasmin C.Hutchinson Christa Winter Paul C.Dalton Lori A.Bolgla Vincent j.Paolone Department of Kinesiology Augusta University112015th St.AugustaGA30912USA Department of Exercise Science&Athletic Training Springfield College263 Alden St.SpringfieldMA01109USA Department of Psychology Springfield College263 Alden St.SpringfieldMA01109USA Heart&Vascular Institute Penn State College of MedicinePenn State University500 HMC Crescent RoadNorth Lobby HersheyPA17033USA Department of Physical Therapy Augusta University112015th St.AugustaGA30912USA

Listening to music manipulates attention to be more externally focused,which has the potential to improve muscular *** study aimed to determine the effect of listening to music on muscle activation during an isometric exercise task,and compare this effect to those of other attentional focus *** healthy subjects(n=35;16 men/19 women)completed an isometric elbow flexion task for 1 min in three randomized and counterbalanced conditions:internal focus(INT),external focus with a simple distraction task(EXT),or listening to music(MUS).Muscle activation of the biceps and triceps brachii and heart rate(Hr)were recorded throughout the exercise *** of perceived exertion(rPE),affective valence,and motivation were measured at the end of each *** was no difference in muscle activation measures among the three *** during MUS was lower than EXT at 15 s([89.4±11.8]beats/min vs.[93.1±12.9]beats/min;p=0.018)and 30 s([90.6±12.4]beats/min vs.[94.2±12.5]beats/min;p=0.026),and lower than INT at 60 s([93.3±13.3]beats/min vs.[96.7±12.0]beats/min;p=0.016).Overall rPE was higher for INT(13.4±2.2)than for MUS([12.6±2.0];p=0.020)and EXT([11.94±2.22];pr for MUS than for INT([2.7±1.4]vs.[2.1±1.5];p=0.011).Manipulating attentional focus did not alter muscle activation for a light-intensity isometric muscular endurance task,though MUS was reported as more positive and requiring less exertion to complete than *** music can therefore be recommended during light-intensity isometric exercise based on the psychological benefits observed.

关键词： Electromyography Attentional focus rating of perceived exertion Elbow flexion

Therapeutic smart-footwear approach for management of neuropathic diabetic foot ulcers:Current challenges and focus for future perspective

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Medicine in Novel Technology and Devices 2024年第3期23卷 1-13页

作者： Stanley I.r.Okoduwa Bernard E.Igiri jerry I.Tagang Ugochi j.Okoduwa Abraham O.Adeyi Directorate of research and Development Nigerian Institute of Leather and Science TechnologyZariaNigeria Department of Biochemistry School of Basic Medical SciencesBabcock UniversityIlishan-RemoNigeria Department of Footwear Technology Nigerian Institute of Leather and Science TechnologyZariaNigeria Industrial and Environmental Pollution Department National Research Institute for Chemical TechnologyZariaNigeria

Diabetic foot ulcers(DFU)have been connected to rising global mortality *** increased plantar tissue stress beneath the numb foot of neuropathy patients is associated with *** article summarises essential therapeutic footwear concepts for the treatment of DFUs and shows how new sensor technologies have made this *** with neuropathic DFUs can address their foot problems with therapeutic footwear without being constrained in their daily *** intervention in maintaining DFUs must be discrete,power-efficient,accurate,and user-friendly in order to offer a trustworthy and acceptable way for effective health *** device can be inserted into a person's shoes from the plantar aspect of the foot to gather more information about their *** findings showed that weight-bearing activities and sensor offloading devices can be employed as effective offloading therapies to heal *** article examines the therapeutic footwear-based technological sensor system,which keeps track of many elements that are helpful in tracking foot ulcers,available treatments,and potential research areas in the future.

关键词： Diabetic foot ulcer Therapeutic footwear Sensors Neuropathy Plantar pressure

Ground-based and additional science support for SMILE

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Earth and Planetary Physics 2024年第1期8卷 275-298页

作者： j.A.Carter M.Dunlop C.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.Milan T.Sergienko r.C.Fear D.G.Sibeck M.Connors T.Yeoman X.Tan M.G.G.T.Taylor K.McWilliams j.Gjerloev r.Barnes D.D.Billet G.Chisham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh Z.-j.Hu M.K.james L.juusola K.Kauristie E.A.Kronberg M.Lester j.Manuel j.Matzka I.McCrea Y.Miyoshi j.rae L.ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang j.Weygand j.Wild j.Yan j.Zhang Q.-H.Zhang Planetary Sciences Group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK rutherford Appleton Laboratory Space Science Technology Facilities CouncilOxfordshireUK School of Space and Environment Beihang UniversityBeijing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100017China Department of Space and Climate Physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK Birkeland Centre for Space Science Department of Physics and Technology.University of BergenBergenNorway Department of Physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 British Antarctic Survey CambridgeUK Swedish Institute of Space Physics KirunaSweden West Highfield Campus University of SouthamptonUniversity RoadSO171BJUK Goddard Space Flight Center NASAGreenbeltMarylandUSA Athabasca University AthabascaCanada ESTEC European Space AgencyNetherlands University of Saskatchewan SaskatoonCanada The johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA Swedish Institude of Space Physics UppsalaSE 75121Sweden Tongji University Shanghai 200092China Center for Space Plasma Physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA Polar research Institute of China Shanghai 200136China Finnish Meteorological Institute(FMI) Finland Department of Earth and Environmental Sciences(Geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany Canadian Space Agency MontrealCanada GFZ German research Centre for Geosciences PotsdamGermany Nagoya University Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 Northumbria University Newcastle upon TyneTyne and WearUK NE18ST National Space Science Center Chinese Academy SciencesBeijing 100190China Arctic Geophysics University Centre in Svalbard

The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMILE ***,we describe current community efforts to prepare for SMILE,and the benefits and context various experiments that have explicitly expressed support for SMILE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these *** include constructing an online SMILE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SMILE mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SMILE conjunctions missions

Impact of welding equipment on power quality

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China Welding 2024年第3期33卷 44-51页

作者： Kovács Attila Molnár judit jármai Károly Institute of Physics and Electrical Engineering Department of Electrical and Electronic Engineering Institutional DepartmentUniversity of MiskolcMiskolc H3515Hungary Institute of Energy and Chemical Engineering University of MiskolcMiskolc H3515Hungary

In an industrial facility,many electrical consumers can affect the quality of ***,the freedom from interference sources of these devices and equipment can be crucial for quality and uninterrupted electricity *** welding equipment is also a possible source of *** electrical harmonic injections created by welding equipment into the electrical network can affect the op-eration of other consumers connected to the given distribution points and cause unjustified overheating and shutdowns of some network *** aim of the research is to analyse the current harmonic injection of welding equipment of different types and modes of oper-ation connected to the internal distribution network of the industrial *** effectiveness of the active harmonic filter built into the welding equipment was also examined in the *** results showed that the built-in active harmonic filter of the DC045 laser welding equipment was ineffective because the total harmonic distortion(THD)was about three times the 8%allowed by IEEE 519−2022 *** current harmonic injection of MIG 320 and MM403 type welding equipment was more than five times the permissible value of 5%.The current harmonic distortion of the PLAS140 type plasma-jet cutter equipment was below the 5%value allowed in the standard,thus it com-plied with *** on the measurement results,it can be concluded that the use of protection against harmonics is also necessary for weld-ing ***,proposals were made in the paper to reduce the effect of harmonics.

关键词： electrical transients harmonic distortion electrical network disturbances voltage breaks total harmonic distortion(THD)

Theory and classification of mass extinction causation

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National Science review 2024年第1期11卷 16-36页

作者： Thomas j.Algeo jun Shen State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan State Key Laboratory of Geological Processes and Mineral resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

COVID-19 vaccination produces exercise-responsive SArS-CoV-2 specific T-cells regardless of infection history

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journal of Sport and Health Science 2024年第1期13卷 99-107页

作者： Kyle A.Smith Tiffany M.Zúñiga Forrest L.Baker Helena Batatinha Charles r.Pedlar Shane C.Burgess Michael P.Gustafson Emmanuel Katsanis richard j.Simpson School of Nutritional Sciences and Wellness The University of ArizonaTucsonAZ 85721USA Department of Pediatrics The University of ArizonaTucsonAZ 85724USA Faculty of Sport Allied Health and Performance ScienceSt.Mary's UniversityTwickenham TW14SXUK Institute of Sport Exercise and Health University College LondonLondon WC1E 7HUUK Department of Animal and Comparative Biomedical Sciences The University of ArizonaTucsonAZ 85721USA The University of Arizona Cancer Center The University of ArizonaTucsonAZ 85719USA Laboratory Medicine and Pathology Mayo Clinic ArizonaPhoenixAZ 85054USA Department of Immunobiology The University of ArizonaTucsonAZ 85724USA Department of Medicine The University of ArizonaTucsonAZ 85724USA Department of Pathology The University of ArizonaTucsonAZ 85724USA

Background:The mobilization and redistribution of severe acute respiratory syndrome coronavirus 2(SArS-CoV-2)specific T-cells and neutralizing antibodies(nAbs)during exercise is purported to increase immune surveillance and protect against severe coronavirus disease 2019(COVID-19).We sought to determine if COVID-19 vaccination would elicit exercise-responsive SArS-CoV-2 T-cells and transiently alter nAb ***:Eighteen healthy participants completed a 20-min bout of graded cycling exercise before and/or after receiving a COVID-19 *** major leukocyte subtypes were enumerated before,during,and after exercise by flow cytometry,and immune responses to SArS-CoV-2 were determined using whole blood peptide stimulation assays,T-cell receptor(TCr)-βsequencing,and SArS-CoV-2 nAb ***:COVID-19 vaccination had no effect on the mobilization or egress of major leukocyte subsets in response to intensity-controlled graded ***,non-infected participants had a significantly reduced mobilization of CD4+and CD8+naive T-cells,as well as CD4+central memory T-cells,after vaccination(synthetic immunity group);this was not seen after vaccination in those with prior SArS-CoV-2 infection(hybrid immunity group).Acute exercise after vaccination robustly mobilized SArS-CoV-2 specific T-cells to blood in an intensity-dependent *** groups mobilized T-cells that reacted to spike protein;however,only the hybrid immunity group mobilized T-cells that reacted to membrane and nucleocapsid *** increased significantly during exercise only in the hybrid immunity ***:These data indicate that acute exercise mobilizes SArS-CoV-2 specific T-cells that recognize spike protein and increases the redistribution of nAbs in individuals with hybrid immunity.

关键词： Anti-viral COVID-19 Exercise immunology SArS-CoV-2 T-Cells Vaccine

An analytical model to estimate the time delay to reach spontaneous ignition considering heat loss in oil reservoirs

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Petroleum Science 2024年第4期21卷 2469-2474页

作者： james j.Sheng Er-Long Yang College of Petroleum Engineering Northeast Petroleum University

During air injection into an oil reservoir, an oxidation reaction generates some heat to raise the reservoir temperature. When the reservoir temperature reaches an ignition temperature, spontaneous ignition occurs. There is a time delay from the injection to ignition. There are mixed results regarding the feasibility of spontaneous ignition in real-field projects and in laboratory experiments. No analytical model is available in the literature to estimate the oxidation time required to reach spontaneous ignition with heat *** paper discusses the feasibility of spontaneous ignition from theoretical points and experimental and field project observations. An analytical model considering heat loss is proposed. Analytical models with and without heat loss investigate the factors that affect spontaneous ignition. Based on the discussion and investigations, we find that it is more difficult for spontaneous ignition to occur in laboratory experiments than in oil reservoirs; spontaneous ignition is strongly affected by the initial reservoir temperature, oil activity, and heat loss; spontaneous ignition is only possible when the initial reservoir temperature is high, the oil oxidation rate is high, and the heat loss is low.

关键词： Spontaneous ignition Time delay Air injection Heat loss Low temperature oxidation Combustion

Contribution to the Full 3D Finite Element Modelling of a Hybrid Stepping Motor with and without Current in the Coils

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journal of Electromagnetic Analysis and Applications 2024年第2期16卷 11-23页

作者： Belemdara Dingamadji Hilaire Mbaïnaïbeye jérôme Guidkaya Golam Department of Physics and Engineering Sciences University of N&#8217Djamena N&#8217Djamena Chad Department of Physics University of Moundou Moundou Chad Department of Physics University of Ngaoundere Ngaoundere Cameroon

The paper presents our contribution to the full 3D finite element modelling of a hybrid stepping motor using COMSOL Multiphysics software. This type of four-phase motor has a permanent magnet interposed between the two identical and coaxial half stators. The calculation of the field with or without current in the windings (respectively with or without permanent magnet) is done using a mixed formulation with strong coupling. In addition, the local high saturation of the ferromagnetic material and the radial and axial components of the magnetic flux are taken into account. The results obtained make it possible to clearly observe, as a function of the intensity of the bus current or the remanent induction, the saturation zones, the lines, the orientations and the magnetic flux densities. 3D finite element modelling provide more accurate numerical data on the magnetic field through multiphysics analysis. This analysis considers the actual operating conditions and leads to the design of an optimized machine structure, with or without current in the windings and/or permanent magnet.

关键词： Modelling 3D Finite Elements Magnetic Flux Hybrid Stepping Motor