261 research outputs found
On synthesis and magnetic properties of YFe(10)Si(2)Z(x) (Z = H and N)
No full textA single phase of the ternary intermetallic compound, YFe10Si2, has been synthesized by a reduction-diffusion process with superfine iron metal, Y2O3 and silicon as the starting materials. All of the compounds, YFe10Si2, YFe10S2H0.3 and YFe10S2N0.5, show the easy magnetization c-axis. For the nitrogen interstitial compound, the Curie temperature increases from 540 to 673 K and the anisotropy field decreases from 27 to 23 KOe. (C) 1998 Elsevier Science S.A.Chemistry, PhysicalMaterials Science, MultidisciplinaryMetallurgy & Metallurgical EngineeringSCI(E)EICPCI-S(ISTP)
Complete hypersurfaces in a Euclidean space Rn+1 with constant mth mean curvature
No full textAbstractIn this paper, we consider n-dimensional oriented complete hypersurfaces with constant mth mean curvature of a Euclidean space Rn+1. We characterize the hypersurface Sk(c)×Rn−k in a Euclidean space Rn+1 and show that generalized Yau conjecture is true for the class of oriented compact locally conformally flat hypersurfaces with positive constant mth mean curvature of a Euclidean space Rn+1. When m=2, our results reduce to the results of Q.-M. Cheng [Q.M. Cheng, Complete hypersurfaces in a Euclidean space Rn+1 with constant scalar curvature, Indiana Univ. Math. J. 51 (2002) 53–68]
Complete self-shrinkers with bounded the second fundamental form in
No full textLet be a complete properly immersed
self-shrinker. In this paper, we prove that if the squared norm of the second
fundamental form satisfies for some constant , then .
Further we classify the -dimensional complete proper self-shrinkers with
constant squared norm of the second fundamental form in ,
which solve the conjecture proposed by Q.M. Cheng and G. Wei when the
self-shrinker is proper.Comment: There is an error in the pape
Stephen S. Gardner and Cass Anthony Collins Jr.
No full textInscribed on back: Camp Lee, VA. Oct -- Commissioned as the youngest second lieutenants at the recent graduation at the Quartermaster School, Camp Lee, Va. were Stephen S. Gardner of 168 Main Street, Wakefield Mass., and Cass Anthony Collins Jr. of 2211 Wabash Street, Detroit, Michigan. Lauded for outstanding work by Brig. General H.L. Whittaker, Q.M. School Commandant, the two officers are among eight men who were commissioned under 21 years of age, in a record graduating class of 1199 officer candidates.https://egrove.olemiss.edu/gartin_photo/1014/thumbnail.jp
Inhibitation of Si-Ge interdiffusion in Ge-on-insulator structures formed by rapid melt growth
No full textHydrogen spillover within carbon-supported palladium catalyst prepared under ultrasound
No full textThe Pd/active-carbon catalyst was prepared in solution through a reduction of Pd-II with formaldehyde, and the obtained metallic particles were around 10-30 Angstrom with a mean size about 16 Angstrom either applying ultrasound in catalyst preparation or varying palladium loading (0.8-5 wt.%). H-2 spillover from Pd onto the carbon surface could occur in Pd/C at 200 degrees C, and H/Pd decreased with the increase of Pd loading; the ultrasound in Pd/C preparation led to a greatly increased amount of spillover H-2, and H/Pd could reach a high value of 6.8 for 0.8 wt.% sonicated Pd/C catalysts. The Pd/C activity (mole H-2/min.g.Pd) in nitrobenzene hydrogenation at 30 degrees C increased with the palladium loading.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000071952700027&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Chemistry, PhysicalSCI(E)CPCI-S(ISTP)
High-Dielectric-Constant All-Organic/Polymeric Composite Actuator Materials
No full textABSTRACTAmong various electroactive polymer (EAP) actuator materials developed recently, the class of EAPs whose responses are stimulated by external electrical fields (often known as the field type EAPs) is especially attractive due to their high strain level and elastic energy density. However, for most field type EAPs, dielectric constant is low, generally less than 10. Consequently, these polymers usually require high electric fields (>100 V/μm) to generate high elastic energy density which limits their applications. In this paper, we will investigate some avenues to significantly raise the dielectric constant and electromechanical response in field type polymeric materials. By exploiting an all-organic composite approach in which high-dielectric-constant organic particulates were blended with a polymer matrix, a polymeric-like material can reach a dielectric constant higher than 400, which results in a significant reduction of the applied field to generate high strain with high elastic energy density. An all-polymer high-dielectric-constant (K>1,000 @1 kHz) percolative composite material was fabricated by the combination of conductive polyaniline particles (K>105) within a fluoroterpolymer matrix (K>50). These high-K polymer hybrid materials also exhibit high electromechanical responses under low applied fields. In addition, a three-component all-organic composite was designed and prepared to improve the dielectric constant and the electromechanical response, as well as the stability of the composites, in which a high-dielectric-constant organic dielectric phase and an organic conductive phase were embedded into the soft dielectric elastomer matrix.</jats:p
Dielectric relaxation and polarization response in relaxor ferroelectric P(VDF-TrFE) copolymer
No full textOn the synthesis and magnetic properties of LnFe(10)Si(2)Z(x) (Z = N,H and Ln = Tb, Er)
No full textSingle-phase products of LnFe(10)Si(2) (Ln=Tb, Er) have been synthesised by a reduction-diffusion process with superfine iron metal as the starting material. The nitrogen interstitial compounds were obtained by direct reaction with nitrogen at high pressure. The introduction of nitrogen changes the easy magnetization direction from basal plane to the c-axis for TbFe10Si2 and from the c-axis to basal plan for ErFe10Si2. (C) 1998 Elsevier Science S.A.Chemistry, PhysicalMaterials Science, MultidisciplinaryMetallurgy & Metallurgical EngineeringSCI(E)EI1ARTICLE1-2297-30026
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