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chemical characteristics of aerosols at coastal station in Hong Kong.Ⅱ. Environmental behavior of trace elements during the April 1995 to April 1996

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journal of Environmental sciences 2004年第2期16卷 212-221页

作者： K.s.lam Z.l.cheng s.c.Kot c.W.Tsang Department of civil and structural Engineering the Hong Kong Polytechnic UniversityResearch Center for Eco-Environmental Sciences Chinese Academy of SciencesDepartment of Mechanical Engineering The Hong Kong University of Science & Technology Clear Water BayDepartment of Applied Biology and Chemical Technology the Hong Kong Polytechnic University Hung Hom Hong Kong ChinaBeijing 100085 ChinaHong Kong ChinaHung Hom Hong Kong China

An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 at coastal region, cape D′Aguilar, in Hong Kong. The trace element composition of aerosol particles(TsP and PM 10 ) were measured and analyzed by using the Instrumental Neutron Activation Analysis(INAA) and Inductive couple Plasma-Mass spectrometry(IcP-Ms) techniques. The results showed that the polluted elements such as: V, Zn, As, Pb, cd, sb, I, se, Bi, with high enrichment factor(E.f) values, are derived from anthropogenic sources, while sc, Al, fe, Mn, sm, la, sr are less than 10 in E.f, these elements are related the crust and soil. The concentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the V or noncrustal V(V *) present summer high and winter low, this phenomenon might be explained by local or regional oil combustion sources. Use three type of elemental ratio, e.g. la/sm, Mn */V * and Bi/Al indicate that both TsP and PM 10 of la/sm ratios are mainly related to soil and dust, Mn */V * are probably represent fossil combustion and Bi/Al are possibly associated with refuse incineration, ferromanganese alloys and aluminum production. The varimax rotation factor analysis for trace elements was performed. By means of the absolute principal component analysis(APcA) and multiple regression, the contribution of trace elements to possible sources and overall means of trace elements were estimated. The results showed that the present station is impacted by the anthropogenic species, although the quantities are different during the summertime and wintertime.

关键词： TsP PM 10 trace elements enhancement factor element ratios seasonal variation factor analysis

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MIcROBRIDGE TEsTING Of YOUNG's MODUlUs AND REsIDUAl sTREss Of NIcKEl fIlM ElEcTROPlATED ON sIlIcON WAfER

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Acta Metallurgica sinica(English letters) 2004年第3期17卷 247-254页

作者： Y.Zhou c.s.Yang j.A. chen G.f. Ding l. Wang M.j Wang Y.M Zhang T.H Zhang Key laboratory for Thin film and Microfabrication of Ministry of Education Research Institute of Micro/Nanometer Science and Technology Shanghai Jiaotong University Shanghai 200030 China state Key laboratory of Nonlinear Mechanics (lNM) Institute of Mechanics The Chinese Academy of Sciences Beijing 100080 China.

Microbridge testing is used to measure the Young's modulus and residual stresses of metallic *** film microbridges with widths of several hundred microns are fabricated by Microelectromechanical *** order to measure the mechanical properties of nickel film microbridges,special shaft structure is designed to solve the problem of getting the load--deflection curves of metal film microbridge by Nanoin--denter XP system with normal Berkovich *** analysis of the micro--bridge load--deflection curve is proposed to evaluate the Young's modulus and residual stress of the films *** calculated results based on the experimental measurements show that the average Young's modulus and residual stress are around 190GPa and 175MPa respectively,while the Young's modulus measured by Nano-hardness method on nickel film with silicon substrate is 186.8±7.34GPa.

关键词： nickel film microbridge MEMs mechanical property loadeflection measurement

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Effect of radiative loss mechanisms on fIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.l silva l.A.O.Nunes s.M.lima l.H.c.Andrade Optical and Photothermal spectroscopy Group(GEOf) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of são carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(fIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the fIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)f_(5/2)→^(4)I_(9/2)/^(4)f_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass fluorescence intensity ratio Optical thermometry judd-Ofelt Rare earths

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Influence of ZnO nanoparticles on the microstructure of a cocrfeMoNi matrix via powder metallurgy

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International journal of Minerals,Metallurgy and Materials 2019年第11期26卷 1467-1476页

作者： c.D.Gómez-Esparza A.Duarte-Moller c.lópez-Díaz de león R.Martínez-sánchez j.f.Hernández-Paz c.A.Rodríguez-González centro de investigación en materiales avanzados(cimav) laboratorio nacional de nanotecnologíamiguel de cervantes no.120chihuahua 31136chi8.mexico facultad de ingeniería civil mecánica e industrialuniversidad de la salle bajíoav.universidad 602león 37150gto.mexico instituto de ingeniería y tecnología universidad autónoma de ciudad juárez(uacj)av.del charro 450 nortec4.juárez 32310chi8.mexico

In the last decade,extensive research has been carried out on the microstructural behavior of high-entropy alloys(HEA),for which the in-situ formation of nanoparticles has been ***,studies of the incorporation of nanoparticles in HEA have been rarely *** this work,the addition of zinc oxide nanoparticles(ZnO NP)as reinforcement in a cocrfeMoNi high-entropy alloy matrix,as well as the morphological,structural,and microstructural evolution of composites synthesized via powder metallurgy,were *** electron microscopy and X-ray diffraction analysis were performed in order to study the microstructural and phase characterization of the *** sintering,it was found that the ZnO NP addition(0.5 wt%,1 wt%and 2 wt%)had a significant influence on the microstructure and hardness of the cocrfeMoNi high-entropy *** bonding among metal particles was promoted with the additions of Zn O NP.A reduction in porosity as a function of ZnO NP content was also *** microhardness results showed that the composite reached its highest reinforcement in bulk samples with 1 wt%ZnO NP(HV 870),which represented a 20%improvement over the unreinforced HEA matrix.

关键词： high-entropy alloy mechanical alloying nanoparticles composites

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EffEcTs Of HIGH TEMPERATURE PRETREATMENTs ON HIGH TEMPERATURE fRAcTURE BEHAVIOR Of sic-c/sic

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Acta Metallurgica sinica(English letters) 2004年第4期17卷 482-486页

作者： X.G.luan l.f.cheng s.R.Qiao j.Zhang laboratory of Thermalstructural composite Materials Northwestern Polytechnical University Xi'an 710072ChinaLaboratory of Thermalstructural Composite Materials Northwestern Polytechnical University Xi'an 710072ChinaLaboratory of Thermalstructural Composite Materials Northwestern Polytechnical University Xi'an 710072ChinaLaboratory of Thermalstructural Composite Materials Northwestern Polytechnical University Xi'an 710072China

The samples made from a sic-c/sic composite were pretreated in AT under creep, fatigue, creep and fatigue interaction, as well as in dry oxygen and wet oxygen under fatigue at 1300℃for 15 hours. The fracture behaviors of the pretreated samples were investigated at 1300℃. The loading-strain curves and the microstructures of the sample were compared with each other. The various of high temperature tensile behaviors was attributed to the different microstructures resulted from different high temperature pretreatments.

关键词： c/sic high temperature tensile behavior fatigue creep

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Variation of sulfate aerosol concentrations over the western Pacific and their effect on clouds, radiation and precipitation

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Acta Oceanologica sinica 1993年第4期12卷 521-534页

作者： f.Parungo j.Rosinski M.l.c.Wu c.T.Nagamoto Air Resources laboratory NOAA/ERL Boulder CO U.S.ANational Center for Atmospheric Research Boulder CO U.S.AGoddard Space Flight Center NASA Greenbelt MD U.S.AAir Resources Laboratory NOAA/ERL Boulder CO U.S.A

Under bilateral cooperation between the United states of America and the People's Republic of china, a series of research cruises were conducted over the western Pacific Ocean. It was found that a) the non-sea-salt sulfate aerosol particles are the major source of cloud condensation nuclei, b) the population of clouds and the total albedo are proportional to the concentration of condensation nuclei and consequently to the concentration of the non-sea-salt aerosol particles, and c) the amount of rainfall is inversely proportional to the concentration of non-sea-salt sulfate aerosol particles. It seems that anthropogenic sulfate aerosol particles affect the regional planetary albedo and climate and that the contribution from biogenically derived sulfate aerosol particles is of lesser importance.

关键词： data Variation of sulfate aerosol concentrations over the western Pacific and their effect on clouds radiation and precipitation over

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structural studies of BaTiO_3:Er^(3+) and BaTiO_3:Yb^(3+) powders synthesized by hydrothermal method

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journal of Rare Earths 2014年第11期32卷 1016-1021页

作者： Garrido-Hernández A García-Murillo A carrillo-Romo f de j cruz-santiago l A chadeyron G Morales-Ramírez A de j Velumani s T.A. Post-graduate student. Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F México Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F Departament of Engineering Materials Tecnológico de Estudios Superiores de Coacalco (TESCo) Av. 16 de Septiembre # 54 Cabecera Municipal C.P. 55700 Coacalco de Berriozábal Estado de México Institut de chimie de clermont-ferrand UMR 6296 CNRS / UBP / ENSCCF 24 avenue des Landais BP 80026 63171 Aubière Cedex – France Department of Electrical Engineering (sEEs) Centro de Investigación y de Estudios Avanzados del IPN Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico D.F. Mexico

Erbium and ytterbium doped barium titanate nanopowders were prepared using the hydrothermal method. A barium titanate structure doped with rare earth ions manifested new characteristics and improved the field of application of optical devices such as trichromatic tubes, lcD displays, lamps, and infrared lasers. In this work, BaTiO3：Er3＋ and BaTiO3：Yb3＋ were prepared using barium chloride [Bacl2], titanium butoxide [c16H36O4Ti], erbium chloride [Ercl3] and ytterbium chloride [Ybcl3] as precursors. Anhydrous methanol was employed as a solvent. Metallic potassium was used to promote solubility in the system and increase the pH to 13. This method yielded the formation of a predominantly cubic structure in both Er3＋ and Yb3＋ doped BaTiO3 powders. characteristic bondings of BaTiO3 were observed with fT-IR spectroscopy. The predominantly cubic structure was confirmed by X-ray diffraction and micro-Raman analyses. The particle size（～30 nm） was estimated using the scherrer equation and X-ray diffraction data. The results were presented and discussed.

关键词： nanopowders hydrothermal BaTiO3:Er3+ BaTiO3:Yb3+ rare earths

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conformable fractional heat equation with fractional translation symmetry in both time and space

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chinese Physics B 2023年第4期32卷 125-129页

作者： W s chung A Gungor j Krız B c lutfuoglu H Hassanabadi Department of Physics and Research Institute of Natural science College of Natural ScienceGyeongsang National UniversityJinju 660-701Korea Mechanical Engineering Akdeniz UniversityAntalyaTurkey Department of Physics University of Hradec KraloveRokitanskeho 6250003 Hradec KraloveCzech Republic Department of Physics Akdeniz UniversityAntalyaTurkey faculty of Physics Shahrood University of TechnologyShahroodIran

We investigate the fractional heat equation with fractional translation in both time and position with different fractional *** examples,we consider a rod and anα-disk with an initial constant temperature and discuss... 详细信息

关键词： fractional derivative heat equation conformable symmetry

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Isogeometric collocation:A Mixed Displacement-Pressure Method for Nearly Incompressible Elasticity Dedicated to Professor Karl stark Pister for his 95th birthday

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computer Modeling in Engineering & sciences 2021年第12期129卷 1125-1150页

作者： s.Morganti f.fahrendorf l.De lorenzis j.A.Evans T.j.R.Hughes A.Reali Department of Electrical Computer and Biomedical EngineeringUniversita degli Studi di PaviaPavia27100Italy Institute of Applied Mechanics Technische Universitat BraunschweigBraunschweig38106Germany Department of Mechanical and Process Engineering Zurich8092Switzerland Department of Aerospace Engineering sciences University of Colorado BoulderColorado80309USA Institute for computational Engineering and sciences The University of Texas at AustinTexas78712USA Department of civil Engineering and Architecture Universita degli Studi di PaviaPavia27100Italy

We investigate primal and mixed u−p isogeometric collocation methods for application to nearly-incompressible isotropic *** primal method employs Navier’s equations in terms of the displacement unknowns,and the mixed method employs both displacement and pressure *** benchmarks for what might be considered acceptable accuracy,we employ constant-pressure Abaqus finite elements that are widely used in engineering *** a basis of comparisons,we present results for compressible *** the methods were completely satisfactory for the compressible ***,results for low-degree primal methods exhibited displacement locking and in general deteriorated in the nearly-incompressible *** results for the mixed methods behaved very well for two of the problems we studied,achieving levels of accuracy very similar to those for the compressible *** third problem,which we consider a“torture test”presented a more complex story for the mixed methods in the nearly-incompressible case.

关键词： Isogeometric analysis isogeometric collocation nearly-incompressible elasticity

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Effect of fuel to Oxidant Molar Ratio on structural and Dc Electrical conductivity of ZnO Nanoparticles Prepared by simple solution combustion Method

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journal of Materials science & Technology 2013年第10期29卷 898-902页

作者： c.s.Naveen M.l.Dinesha H.s.jayanna Department of PG studies and Research in Physics Kuvempu University

ZnO nanoparticles of different sizes were prepared by varying the molar ratio of glycine and zinc nitrate hexahydrate as fuel and oxidizer （0.1, 0.8, 1.11, 1.3, 1.5, 1.7, 2.0） by simple solution combustion method. UV-Visible spectrophotometry studies show that, the band gap of the prepared ZnO nanoparticles increases with increasing fuel to oxidant （f/O） molar ratio up to 1.7 revealing the formation of ZnO nanoparticles. The decrease in band gap for the sample of f/O molar ratio 2.0 is due to an increase in particle size. Powder X-ray diffraction patterns of the prepared samples show the formation of single phase ZnO nanoparticles and the particle size decreases with increasing f/O molar ratio up to 1.7. surface morphology of the prepared samples was studied by scanning electron microscopy and it was observed that, the porosity increases with increasing f/O molar ratio. Dc electrical conductivity at room temperature and in the temperature range of 303-563 K was studied for all the samples and the results revealed that, the sample of f/O molar ratio 1.7 has low electrical conductivity at room temperature and high EAR （high temperature activation energy） compared to other samples.

关键词： ZnO nanoparticles structural characterization Electrical conductivity

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