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Acta metallurgica Sinica(English Letters) 2017年第1期30卷 29-35页

作者： A.Alshareef K.Laird R.B.m.Cross Faculty of Technology School of Engineering and Sustainable DevelopmentEmerging Technologies Research CentreDe Montfort UniversityLeicester LE1 9BHUK Faculty of Health and Life Sciences Leicester School of PharmacyDe Montfort UniversityLeicester LE1 9BHUK

The interest in synthesising inorganic nanomaterials for biological applications has increased in recent years, especially for antibacterial purposes. In the present study, spherical and cube-shaped copper nanoparticles were synthesised by a chemical reduction method and their efficacy as anfimicrobial agents against both Gram-negative （Escherichia coli） and Gram-positive （Enterococcus sp.） organisms investigated. The nanoparticles were characterised using ultraviolet/ visible spectroscopy, scanning electron microscopy, energy-dispersive spectroscopy and X-ray diffraction. Copper nanocubes were found to be more antimicrobial when compared with copper nanospheres, and it is postulated that whilst both sets of nanoparticles have similar total surface areas, the different shapes have different active facets and surface energies, which may lead to differing bactericidal behaviour.

关键词： Copper nanoparticles Scanning electron microscopy (SEm) Antibacterial Escherichia coli Enterococcus sp.

Review on nanocomposites fabricated by mechanical alloying

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International Journal of minerals,metallurgy and materials 2019年第9期26卷 1047-1058页

作者： mohammed A. Taha Rasha A. Youness m.F. Zawrah Solid State Physics Department National Research CentreEl Buhouth St.Dokki 12622CairoEgypt Spectroscopy Department National Research CentreEl Buhouth St.Dokki 12622CairoEgypt Refractories Ceramics and Building Material DepartmentNational Research CentreEl Buhouth St.Dokki 12622CairoEgypt

Composites are composed of multiphase materials, where each phase has specific properties that differ from those of the other phases which can effect on the whole properties of composite. Nanocomposites are class of materials that contain at least one phase in the nanometric size range and can be produced by any suitable technique for preparing nanomaterials. Composites are an interesting class of materials that have recently been used in numerous applications, including structural, biomedical, electronics, and environmental applications. In composites, reinforcements might be fibers, particulates, or whiskers. mechanical alloying(mA) is a promising technique for producing nanocomposite materials that are difficult or impossible to prepare via conventional techniques. In this review, we provide an overview of nanocomposites prepared by the mA process. The mechanism of milling and other milling parameters are overviewed, and insights into sintering categories and parameters are also presented.

关键词： nanocomposites mechanical alloying fabrication sintering

HEAT TRANSFER OF TiO_2/WATER NANOFLUID IN A COILED AGITA-TED VESSEL WITH PROPELLER

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Journal of Hydrodynamics 2012年第6期24卷 942-950页

作者： PERARASU V.T. ARIVAZHAGAN m. SIVASHANmUGAm P. Heat Transfer Research Laboratory Department of Chemical EngineeringNational Institute of Technology

An attempt is made to investigate heat transfer enhancement using nanofluid in a coiled agitated vessel fitted with propeller agitator. The heat transfer coefficient in coiled agitated vessel for water and TiO2/water nanofluid of 3 different volume concentrations （0.10%, 0.20% and 0.30%） are estimated and compared. The heat transfer coefficient for nanofluid is found to be higher than that for water and also found to increase with increasing volume concentrations. The enhancement in the convective heat transfer using nanofluid is found to be a maximum of 17.59%. Empirical correlations are separately formed for water and TiO2/water nanofluid as well as found to fit the experimental data within ±5% for water and within ±10% for nanofluid.

关键词： coiled agitated vessel heat transfer enhancement Nusselt number TiO2/water nanofluid

Effective thermal conductivity of an intact heterogeneous limestone

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Journal of Rock mechanics and Geotechnical Engineering 2020年第4期12卷 682-692页

作者： A.P.S.Selvadurai S.m.Rezaei Niya Department of Civil Engineering and Applied mechanics McGill UniversityMontrealQCH3A 0C3Canada Royal melbourne Institute of Technology MelbourneAustralia

The Cobourg limestone is a very low porosity rock consisting of lighter nodular regions that are predominantly calcite and darker regions consisting of calcite,quartz,dolomite,and an appreciable clay *** paper presents the application of the theory of multi-phasic composites to estimate the possible maximum effective thermal conductivity of the heterogeneous *** thermal conductivity estimates are expected to be representative of the intact rock,without fractures or fissures that can influence the heat conduction *** estimates are therefore indicative of the thermal properties of the rock in undisturbed regions unaffected by the influences of stress relief and excavation damage during construction of deep ground repositories for the disposal of heat-emitting nuclear waste.

关键词： Thermal conductivity Cobourg limestone multi-phasic approach Voigt,Reuss and Hill estimates Hashin and Shtrikman bounds Computational modeling

Science missions Using CubeSats

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空间科学学报 2020年第4期40卷 443-461页

作者： SEYEDABADI m E FALANGA m AZAm m BARESI N FLÉRON R JANTARACHOTE V JUAREZ ORTIZ V A JULCA YAYA J J LANGER m mANUTHASNA S mARTINOD N mUGHAL m R NOmAN m PARK J PImNOO A PRAKS J REYNERI L SANNA A ŞIŞmAN TÇ SOmE J ULAmBAYAR T YU Xiaozhou DONG Xiaolong BALDIS L Asia-Pacific Space Cooperation Organization 100070 BeijingChina International Space Science Institute-Beijing 100190 BeijingChina International Space Science Institute 3012 BernSwitzerland Bangladesh Space Research and Remote Sensing Organization 1207 DhakaBangladesh Japan Aerospace Exploration Agency Institute of Space Astronautical Science252-5210 TokyoJapan Technical University of Denmark 2800 LyngbyDenmark Department of Electrical Engineering Faculty of EngineeringPrince of Songkla University90112 SongkhlaThailand National Commission of Aerospace Research and Development 15046 San IsidroPeru Technical University of munich 80333 MunichGermany mahanakorn University of Technology 10530 BangkokThailand Swiss Federal Institute of Technology Lausanne 1015 LausanneSwitzerland Institute of Space Technology 44000 IslamabadPakistan Korea Astronomy and Space Science Institute 34055 DaejeonSouth Korea Geo-Informatics and Space Technology Development Agency 10210 BangkokThailand Department of Electronics and Nanoengineering Aalto University02150 EspooFinland Department of Electronics and Telecommunications Polytechnic of Turin10129 TurinItaly Department of Physics University of Cagliari09042 MonserratoItaly Department of Astronautical Engineering University of Turkish Aeronautical Association06790 AnkaraTurkey Nanosatellite Development Laboratory National University of Mongolia210646 UlaanbaatarMongolia Dalian University of Technology 116024 DalianChina National Space Science Center 100190 BeijingChina

As the role of missions and experiments carried out in outer space becomes more and more essential in our understanding of many earthly problems,such as resource management,environmental problems,and disaster management,as well as space science questions,thanks to their lower cost and faster development process CubeSats can benefit humanity and therefore,young scientists and engineers have been motivated to research and develop new CubeSat *** very long after their inception,CubeSats have evolved to become accepted platforms for scientific and commercial *** last couple of years showed that they are a feasible tool for conducting scientific experiments,not only in the Earth orbit but also in the interplanetary *** many countries,a CubeSat mission could prompt the community and young teams around the world to build the national capacity to launch and operate national space *** paper presents an overview of the key scientific and engineering gateways opened up to the younger scientific community by the advent and adaptation of new technology into CubeSat *** role of cooperation and the opportunities for capacity-building and education are also ***,the present article also aims to provide useful recommendations to scientists,early-career researchers,engineers,students,and anyone who intends to explore the potential and opportunities offered by CubeSats and CubeSats-based missions.

关键词： CubeSat Space science Small satellites for space science Education Earth observation

Comparison between the volumetric flow rate and pressure distribution for different kinds of sliding thrust bearing

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Propulsion and Power Research 2015年第2期4卷 84-90页

作者： O.Pourmehran m.Rahimi-Gorji m.Gorji-Bandpy m.Baoub Faculty of mechanical Engineering Babol Noshirvani University of TechnologyBabolIran Faculty of mechanical Engineering Shahrood University of TechnologyShahroodIran

In this paper a hydrodynamic journal sliding bearing,forming with two nonparallel surfaces that the lower surface moves with a unidirectional velocity and the upper surface is stationary shaped with exponential geometry is verified *** values of volumetric flow rate and distribution of pressure for incompressible lubricant flow between two supports in several conditions of velocity with different variables are *** results indicate that by increasing the amount of constant(m),the maximum oil pressure in the bearing will face an extreme decrease,and also by increasing theαcoefficient,the rate of volumetric flow rate will decrease.

关键词： Non-parallel plate bearing Hydrodynamic sliding bearing Incompressible lubricant flow Volumetric flow rate Exponential geometry

Optical bistability and multistability via double dark resonance in graphene nanostructure

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Chinese Physics B 2016年第6期25卷 223-229页

作者： Seyyed Hossein Asadpour G Solookinejad m Panahi E Ahmadi Sangachin Department of Physics Marvdasht BranchIslamic Azad University

Electrons in graphene nanoribbons can lead to exceptionally strong optical responses in the infrared and terahertz regions owing to their unusual dispersion ***,on the basis of quantum optics and solid-material scientific principles,we show that optical bistability and multistability can be generated in graphene nanostructure under strong magnetic *** also show that by adjusting the intensity and detuning of infrared laser field,the threshold intensity and hysteresis loop can be manipulated *** effects of the electronic cooperation parameter which are directly proportional to the electronic number density and the length of the graphene sample are *** proposed model may be useful for the nextgeneration all-optical systems and information processing based on nano scale devices.

关键词： optical bistability optical multistability graphene nanostructure

Synthesis, spectroscopic characterization, and thermal decomposition kinetics of some lanthanide(III) nitrate complexes of 2-(N-o-hydroxyacetophenone) amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene

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Journal of Rare Earths 2008年第4期26卷 463-468页

作者： K. mohanan m. Thankamony B. Sindhu Kumari Department of Chemistry University of Kerala Kariavattom Campus Trivandrum-695 581. Kerala India

Complexes of La（Ⅲ）, Ce（Ⅲ）, Pr（Ⅲ）, Nd（Ⅲ）, Sm（Ⅲ）, Eu（Ⅲ）, Gd（Ⅲ）, Dy（Ⅲ）, Yb（Ⅲ）, and Lu0ID with 2-（N-o- hydroxyacetophenone）amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene （HAAT） formed by the condensation of o-hydroxyacetophenone and 2-amino-3-carboxyethyl-4,5,6,7-tetrahydrobenzo[b]thiophene were synthesized and characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility data, UV-Visible, IR, and NmR spectral studies. The spectral data revealed that the ligand acted as a neutral tridentate coordinating to the metal ion through ONO donor sequence. A coordination number nine was proposed for the complexes. Thermal decomposition studies of the ligand and lanthanum（Ⅲ） complex were carried out and kinetic parameters were calculated using Coats-Redfem equation. The decomposition reactions followed random nucleation mechanism with one nucleus on each particle.

关键词： lanthanides o-hydroxyacetophenone molar conductance magnetic susceptibility thermal study rare earths

Accelerating Role of Clay in Photo-Oxidation of Polypropylene/Clay multifilament Yarns

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Chinese Journal of Polymer Science 2014年第5期32卷 609-619页

作者： S.Aslanzadeh R.Semnani Rahbar m.Nazi Department of Textile and Leather Faculty of Chemistry and Petrochemical Engineering Standard Research Institute (SRI)

Photo-oxidative degradation of polypropylene/clay multifilament yarns containing different amounts of clay was investigated. These samples and pure polypropylene （PP） multifilametns were exposed to long wavelength radiations （λ〉 300 nm） under atmospheric condition of constant temperature and relative humidity. The photo-oxidative stability was studied using FTIR spectroscopy, tensile testing and microscopy. The results indicate that the addition of clay particles decreases the stability of PP/clay composites to photo-oxidative degradation according to comparison with pure PP. From FTIR study and tensile properties, it was also found that the multifilaments with higher clay loading reveals a faster loss of mechanical properties, higher photo-oxidative product formation and more reduction in the induction time of photo-oxidation. moreover, the crack formation on surface of irradiated filaments corresponds well to the conclusions in tensile properties and FTIR characterization.

关键词： Photo-oxidation Polypropylene multifilarnent yams Nanoclay UV radiation.

Field-dependent spin waves in high-aspect-ratio singlecrystal ferromagnetic nanowires

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Nano Research 2016年第5期9卷 1426-1433页

作者： Semanti Pal Susmita Saha m. Venkata Kamalakar Anjan Barman Department of Condensed matter Physics and material Sciences S. N. Bose National Centre for Basic Sciences Block JD Sector Ⅲ Salt Lake Kolkata 700 098 India Department of Physics and Astronomy Uppsala University Box 516 75120 Uppsala Sweden

We investigate the spin wave （SW） modes in high-aspect-ratio single-crystal ferromagnetic nanowires （FmNWs） using an all-optical time-resolved magnetooptical Kerr effect （TR-mOKE） microscope. The precessional magnetization dynamics in such FmNWs unveil the presence of uniform and quantized SW modes that can be tuned by varying the bias magnetic field （H）. The frequencies of the modes are observed to decrease systematically with a decreasing magnetic field, and the number of modes in the spectrum is reduced from four to three for H 〈 0.7 kOe. To understand these results, we perform micromagnetic simulations that reveal the presence of edge, standing wave, and uniform SW modes in the nanowires （NWs）. Our simulations clearly show how the standing wave and uniform SW modes coalesce to form a single mode with uniform precession over the entire NW for H 〈 0.7 kOe, reproducing the experimentally observed reduction in modes. Our study elucidates the possibility of manipulating the SW modes in magnetic nanostructures, which is useful for applications in magnonic and spintronic devices.

关键词： Field-dependent high-aspect-ratio nanowires