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Propulsion and Power Research 2024年第3期13卷 360-374页

作者： s.W.Chen W.H.Li C.Xu Q.H.Meng school of Energy science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150001China AVIC shenyang Aircraft Design and Research Institute Shenyang 110035China

sweeping jet actuator(sJA)has been widely applied for activeflow control in *** this paper,the sJA character in compressor cascade and its performance for separation control in innerflows are ***-averaged and transientflowfield measurement,together with visualization methods are *** is found that endwall effects are important for both sJA behaviors and sJA performance for separation control in compressor *** is a maximum of 12.7%total pressure loss reduction with sJA placed near the separation position,close to the endwall and under *** characteristic frequencies in theflowfield contribute to the capture of influence regions of vortices and excitation *** concentrated shedding vortices and sJA jets impact region helped to judge that sJA energizes low momentumfluids in a large region and matches the high loss core *** be concrete,theflow separation control mechanism of sJA lies on the interruption of the blade suction surface boundary layer development and the restriction of the lifting of the boundary layer from end-wall towards blade suction surface.

关键词： Compressor cascade Activeflow control sweeping jet actuator Corner separation Oilflow visualization

sources and Deficiency Diseases of Mineral Nutrients in Human Health and Nutrition:A Review

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Pedosphere 2014年第1期24卷 13-38页

作者： u.C.GuPTA s.C.GuPTA Agriculture and Agri-Canada Canada Crops and Livestock Research Centre The Department of Plastic surgery Loma Linda University

Mineral nutrients are fundamentally metals and other inorganic compounds. The life cycle of these mineral nutrients begins in soil, their primary source. soil provides minerals to plants and through the plants the minerals go to animals and humans; animal products are also the source of mineral nutrients for humans. Plant foods contain almost all of the mineral nutrients established as essential for human nutrition. They provide much of our skeletal structure, e.g., bones and teeth. They are critical to countless body processes by serving as essential co-factors for a number of enzymes. Humans can not utilize most foods without critical minerals and enzymes responsible for digestion and absorption. Though mineral nutrients are essential nutrients, the body requires them in small, precise amounts. We require them in the form found in crops and they can be classified into three different categories： major, secondary, and micro or trace minerals. This classification is based upon their requirement rather than on their relative importance. Major minerals such as potassium （K） and phosphorus （P） are required in amounts of up to 10 g d-1. The daily requirement of secondary and micro minerals ranges from 400 to 1 500 mg d-1 and 45 ~tg d-1 to 11 mg d-1, respectively. To protect humans from mineral nutrient deficiencies, the key is to consume a variety of foods in modest quantities, such as different whole grains, low fat dairy, and different meats, vegetables and fruits. For insurance purposes, a supplement containing various mineral nutrients can be taken daily.

关键词： deficiency diseases deficiency symptoms origin recommended daily dose toxicity

Pitting corrosion behavior and corrosion protection performance of cold sprayed double layered noble barrier coating on magnesium-based alloy in chloride containing solutions

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Journal of Magnesium and Alloys 2023年第9期11卷 3099-3119页

作者： M.Daroonparvar A.Helmer A.M.Ralls M.u.Farooq khan A.K.Kasar R.K.Gupta M.Misra s.shao P.L.Menezes N.shamsaei National Center for Additive Manufacturing Excellence Auburn UniversityAuburnAL 36849USA Department of Mechanical Engineering Auburn UniversityAuburnAL 36849USA Department of Materials science and Engineering College of EngineeringNorth Carolina State University911 Partners WayRaleighNC 27695USA Department of Mechanical Engineering University of Nevada RenoRenoNV 89501USA Department of Nuclear Engineering and Radiological sciences University of MichiganAnn ArborMI 48105 USA Department of Chemical and Materials Engineering University of Nevada RenoNV 89501USA

Nitrogen processed, cold sprayed commercially pure(CP)-Al coatings on Mg-based alloys mostly lack acceptable hardness, wear resistance and most importantly are highly susceptible to localized corrosion in chloride containing solutions. In this research, commercially pure α-Ti top coating having good pitting potential(~1293 mV_(sCE)), high microhardness(HV_(0.025): 263.03) and low wear rate was applied on a CP-Al coated Mg-based alloy using high pressure cold spray technology. Potentiodynamic polarization(PDP) curves indicated that the probability of transition from metastable pits to the stable pits for cold spayed(Cs) Al coating is considerably higher compared to that with the Cs Ti top coating(for Ti/Al/Mg system). In addition, Cs Ti top coating was in the passivation region in most pH ranges even after 48 h immersion in 3.5 wt% NaCl solution. The stored energy in the Cs Ti top coating(as a passive metal) was presumed to be responsible for the easy passivation. Immersion tests indicated no obvious pits formation on the intact Cs Ti top coating surface and revealed effective corrosion protection performance of the Cs double layered noble barrier coatings on Mg alloys in 3.5 wt% NaCl solution even after 264 h.

关键词： Ti coating Mg alloys Localized corrosion Passivity Dislocation density Crystallite size

Effect of deep cryogenic treatment on the microstructural,mechanical and ballistic properties of AA7075-T6 aluminum alloy

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Defence Technology（防务技术） 2023年第12期30卷 101-110页

作者： s.Dharani kumar u.Magarajan saurabh s Kumar Rodríguez-Millan M Centre for Machining and Material Testing KPR Institute of Engineering and TechnologyCoimbatoreIndia Department of Mechanical Engineering Sri Venkateswara College of EngineeringChennaiIndia scientific Officer Ballistic Research Centre&Testing RangeNational Forensic Sciences UniversityGandhi NagarIndia Department of Mechanical Engineering University Carlos Ⅲ of MadridLeganesMadridSpain

The study focused on investigating the effect of Deep Cryogenic Treatment(DCT)on the mechanical and ballistic properties of AA7075-T6 aluminum *** microstructure,microhardness,tensile strength,and impact strength of the Base Material(BM)and DCT-treated 7075 samples were analyzed through metallographic analysis and mechanical *** microstructure of the DCT-treated 7075 samples revealed fine grains and a distribution of secondary phase *** tensile strength,impact strength,and microhardness of DCT-treated samples increased by 7.41%,4%,and 9.68%,respectively,compared to the BM *** fractography analysis of the tensile samples showed cleavage facets,microvoids,and dimples in both the *** ballistic behavior of the BM and DCT target plates were studied by impacting hard steel core projectiles at a velocity of 750±10 m/*** target plates failed due to petaling and ductile hole enlargement,and the depth of penetration(DOP)of the DCT target was less than that of the BM target,indicating a higher ballistic *** post-ballistic microstructure examination of the target plates showed the formation of an Adiabatic shear Band(AsB)without any *** was concluded that the DCT treatment improved the mechanical and ballistic properties of the aluminum alloy due to grain refinement and high dislocation density.

关键词： Deep cryogenic treatment AA7075-T6 Mechanical properties Ballistic Adiabatic shear band

substitution of Pb with (Li_(1/2)Bi_(1/2)) in PbZrO_(3)-based antiferroelectric ceramics

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Journal of Advanced Dielectrics 2024年第1期14卷 74-81页

作者： Binzhi Liu Anand P.s.Gaur Jun Cui Xiaoli Tan Department of Materials science and Engineering Iowa state university AmesIA 50011USA

PbZrO_(3)-based antiferroelectric(AFE)ceramics are promising dielectrics for high-energy-density capacitors due to their reversible phase transitions during charge-discharge *** this work,a new composition series,[Pb_(0.93-x)La_(0.02)(Li_(1/2)Bi_(1/2))_(x)sr_(0.04)][Zr_(0.57)sn_(0.34)Ti_(0.09)]O_(3),with Li^(+)and Bi^(3+)substitution of Pb^(2+)at x=0,0.04,0.08,0.12,0.16 is investigated for the microstructure evolution,ferroelectric(FE)and dielectric *** is found that Li^(+) and Bi^(3+) substitution can significantly reduce the sintering temperature and simultaneously enhance the dielectric breakdown *** ultrahigh energy efficiency(94.0%)and a large energy density(3.22 J/cm^(3))are achieved in the composition of x=0.12 with a low sintering temperature(1075℃).

关键词： PbZrO_(3)-based antiferroelectrics LiþBi substitution energy storage energy efficiency

Combatting anthrax outbreaks across Nigeria's national land borders: need to optimize surveillance with epidemiological surveys

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Infectious Diseases of Poverty 2024年第1期13卷 100-100页

作者： Hammed O.Mogaji Babatunde Adewale stella I.smith Ehimario u.Igumbor Chidumebi J.Idemili Andrew W.Taylor-Robinson Yale school of Public Health Yale University New Haven USA Parasitology and Epidemiology unit Federal University Oye-Ekiti Oye-Ekiti Nigeria Department of Public Health and Epidemiology Nigerian Institute of Medical Research Lagos Nigeria Department of Molecular Biology and Biotechnology Nigerian Institute of Medical Research Lagos Nigeria Centre for Infectious Disease Research Nigerian Institute of Medical Research Lagos Nigeria Department of Public Health Walter Sisulu University Mthatha South Africa Institute of Health Policy Management and Evaluation University of Toronto Toronto Canada College of Health sciences Vin University Hanoi Vietnam Center for Global Health Perelman School of Medicine University of Pennsylvania Philadelphia USA

Background Anthrax is a non-contagious zoonotic disease caused by the Gram-positive,spore-forming bac-terium Bacillus *** is common in livestock and wild animals such as cattle,goats,sheep,camels,and *** humans,anthrax may occur after contact with contaminated carcasses or animal products like milk and *** best method to prevent anthrax in people is to ensure livestock are vaccinated,which significantly limits the risk of zoonotic spread to ***,the rate of vaccination of domesticated animals kept by nomadic pastoralists in West Africa is *** groups regularly cross over national boundaries with their grazing *** is a country that historically has done comparatively well to contain this public health ***,in 2023 several outbreaks of human disease appear linked to the consumption of anthrax-contaminated animal products brought into Nigeria by pastoralists from neighboring *** manifestations include skin sores or ulcers,nausea,vomiting,and *** article aims to raise awareness of recent outbreaks of anthrax in West Africa and to callfor a renewed focus on measures to combat this neglected public health concern to the *** body The imperative to pinpoint pivotal issues relating to the ongoing emergence of anthrax cases in Nigeria cannot be *** delving into the prevalence of anthrax in both livestock and human populations residing along Nigeria's borders,unraveling the genetic diversity and potential sources of *** strains,and identify-ing the primary animal host(s)responsible for transmission,we stand to enhance our understanding of this critical ***,investigating the multifaceted factors contributing to anthrax transmission,assessing community knowledge and practices,mapping common migratory routes of pastoralists,and formulating targeted interven-tion strategies tailored to the challenges of border communities,are each crucial steps towards eff

关键词： border Combat doubt

A carbuncle cure for the Harten-Lax-van Leer contact(HLLC)scheme using a novel velocity-based sensor

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Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1259-1278页

作者： u.s.VEVEK B.ZANG T.H.NEW Department of Mechanical Materials and Aerospace EngineeringUniversity of LiverpoolLiverpool L693BXUnited Kingdom Department of Aerospace Engineering University of BristolBristol BS81TRUnited Kindgdom school of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

A hybrid numerical flux scheme is proposed by adapting the carbunclefree modified Harten-Lax-van Leer contact(HLLCM) scheme to smoothly revert to the Harten-Lax-van Leer contact(HLLC) scheme in regions of shear. This hybrid scheme, referred to as the HLLCT scheme, employs a novel, velocity-based shear sensor. In contrast to the non-local pressure-based shock sensors often used in carbuncle cures, the proposed shear sensor can be computed in a localized manner meaning that the HLLCT scheme can be easily introduced into existing codes without having to implement additional data structures. Through numerical experiments, it is shown that the HLLCT scheme is able to resolve shear layers accurately without succumbing to the shock instability.

关键词： carbuncle shock instability Euler equation numerical flux Harten-Laxvan Leer contact(HLLC)scheme

Atomistic Investigation of shock-Induced Amorphization within Micro-shear Bands in Hexagonal Close-Packed Titanium

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Acta Metallurgica sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： Z.C.Meng K.G.Wang T.Ali D.Li C.G.Bai D.s.Xu s.J.Li A.H.Feng G.J.Cao J.H.Yao Q.B.Fan H.Wang R.Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China school of Materials science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary Centre for Additive Manufacturing(ICAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China school of Materials science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of science and Technology on Materials under shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic deformation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induced a large number of stacking faults(sFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming sFs and dislocations,there was a gradual increase in the density of dislocations and sFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： shock compression Amorphization shear band Titanium Molecular dynamics

Incorporation of a nanotechnology-based additive in cementitious products for clay stabilisation

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1056-1069页

作者： E.u.Eyo s.Ng’ambi s.J.Abbey school of Energy Construction and EnvironmentFaculty of EngineeringEnvironment and ComputingCoventry UniversityCoventryUK Faculty of Environment and Technology Department of Geography and Environmental ManagementCivil Engineering ClusterUniversity of the West of EnglandBristolUK

The mechanical performances and water retention characteristics of clays,stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem(RC),are studied in this *** unconfined compression tests and one-dimensional oedometer swelling were performed after 7 d of curing to understand the influence of addition of 1%of RC material in the stabilised soils with the cement partially replaced by 49%,59%and 69%of ground granulated blast furnace slag(GBBs)or pulverised fuel ash(PFA).The moisture retention capacity of the stabilised clays was also explored using the soil-water retention curve(sWRC)from the measured *** confirmed an obvious effect of the use of RC with the obtained strength and swell properties of the stabilised clays suitable for road application at 50%replacement of *** outcome is associated with the in-depth and penetrating hydration of the cementitious materials by the RC and water which results in the production of needle-like matrix with interlocking filaments e a phenomenon referred to as the‘wrapping’*** the other hand,the sWRC used to describe the water holding capacity and corresponding swell mechanism of clays stabilised by a proportion of RC showed a satisfactory *** moisture retention of the RC-modified clays was initially higher but reduced subsequently as the saturation level increased with decreasing *** phenomenon confirmed that clays stabilised by including the RC are water-proof in nature,thus ensuring reduced porosity and suction even at reduced water ***,the stabilised clays with the combination of cement,GGBs and RC showed a better performance compared to those with the PFA included.

关键词： Cement Ground granulated blast furnace slag(GBBs) Fly ash RoadCem(RC) swell stabilisation unconfined compressive strength soil-water retention curve(sWRC)

Application of Reactive Ion Etching to the Fabrication of Microstructure on Mo/si Multilayer

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Chinese Physics Letters 1999年第9期16卷 665-666页

作者： LE Zi-chun L.Dreeskornfeld s.Rahn R.segler u.Kleineberg u.Heinzmann Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012 Fakultät für Physik Universität BielefeldUniversitatsstraβe 25D-33615 BielefeldGermany

Mo/si muitilayer mirrors(30 periods,doublelayer thickness 7nm)with the AZ-PF514 resist pattern whose smallest lines and spaces structure was 0.5pm were etched by reactive ion etching(RIE)in a fluorinated *** etch rate,selectivity and etch profile were investigated as a function of the gas mixture,pressure,and plasma rf *** groove depth and the etch proHle were investigated by an atomic force microscope before RIE,after RIE and after resist removal.

关键词： Mo/si smallest selectivity