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排序方式: 共有178条查询结果,搜索用时 16 毫秒
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Georgiana Dascalu Gloria Pompilian Bertrand Chazallon Valentin Nica Ovidiu Florin Caltun Silviu Gurlui Cristian Focsa 《Applied Physics A: Materials Science & Processing》2013,110(4):915-922
CoFe2O4 thin films with preferential texture structure, small grain size, and perpendicular magnetic anisotropy can be obtained by the pulsed laser deposition (PLD) technique. In this work, we studied the influence of the Fe3+ ions substitution by three elements from lanthanide group (Dy, La, and Gd) on the structural properties of the thin films. The samples were deposited by Nd:YAG laser (λ=532 nm, 10 ns) ablation of CoFe1.8RE0.2O4, (RE=Dy, La, Gd) targets at various substrate temperatures ranging from room temperature to 600 °C. The microstructure and chemical composition of the thin films were investigated by Raman spectroscopy, XRD, SEM-EDS, and ToF-SIMS. The XRD patterns and Raman spectra of the thin films indicated the formation of a single spinel structure. Thus, the desired substitution of the iron ions in the spinel lattice with the RE elements was achieved in the thin films, although in the bulk material, their presence determined the formation of a residual phase with a perovskite-type structure. 相似文献
23.
Ovidiu Furdui 《Journal of Mathematical Analysis and Applications》2008,342(2):773-779
In this paper we consider a special class of lacunary series and we characterize their membership in the BMOA of the unit ball of Cn in terms of their Taylor coefficients. In addition, we show that a similar result holds for the class VMOA. 相似文献
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Ovidiu Savin 《Calculus of Variations and Partial Differential Equations》2005,22(3):303-320
We consider the following obstacle problem for Monge-Ampere equation
and discuss the regularity of the free boundary
. We prove that
is
if f is bounded away from 0 and
, and it is C
1,1 if
.Received: 4 February 2003, Accepted: 3 March 2004, Published online: 16 July 2004 相似文献
26.
Cretu O Krasheninnikov AV Rodríguez-Manzo JA Sun L Nieminen RM Banhart F 《Physical review letters》2010,105(19):196102
Reconstructed point defects in graphene are created by electron irradiation and annealing. By applying electron microscopy and density functional theory, it is shown that the strain field around these defects reaches far into the unperturbed hexagonal network and that metal atoms have a high affinity to the nonperfect and strained regions of graphene. Metal atoms are attracted by reconstructed defects and bonded with energies of about 2?eV. The increased reactivity of the distorted π-electron system in strained graphene allows us to attach metal atoms and to tailor the properties of graphene. 相似文献
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Klein DJ Ivanciuc T Ryzhov A Ivanciuc O 《Combinatorial chemistry & high throughput screening》2008,11(9):723-733
Reaction networks are viewed as derived from ordinary molecular structures related in reactant-product pairs so as to manifest a chemical super-structure. Such super-structures then are candidates for applications in a general combinatoric chemistry. Notable additional characterization of a reaction super-structure occurs when such reaction graphs are directed, as for example when there is progressive substitution (or addition) on a fixed molecular skeleton. Such a set of partially ordered entities is in mathematics termed a poset, which further manifests a number of special properties, as then might be utilized in different applications. Focus on the overall "super-structural" poset goes beyond ordinary molecular structure in attending to how a structure fits into a (reaction) network, and thereby brings an extra "dimension" to conventional stereochemical theory. The possibility that different molecular properties vary smoothly along chains of interconnections in such a super-structure is a natural assumption for a novel approach to molecular property and bioactivity correlations. Different manners to interpolate/extrapolate on a poset network yield quantitative super-structure/activity relationships (QSSARs), with some numerical fits, e.g., for properties of polychlorinated biphenyls (PCBs) seemingly being quite reasonable. There seems to be promise for combinatoric posetic ideas. 相似文献
30.
Gordan OD Persson BN Cesa CM Mayer D Hoffmann B Dieluweit S Merkel R 《Langmuir : the ACS journal of surfaces and colloids》2008,24(13):6636-6639
Nano- and micromolding of elastic materials produces smoothed replicas of the mold structures. This limits the technique's resolution. Here we identified surface tension as the cause of smoothing and derived explicit equations for calculating molded feature shapes. The characteristic length scale for smoothing is given by the ratio of the interface tension to Young's modulus of the molded material. This approach offers the possibility to correct for the smoothing caused by surface tension during mold design. Moreover, it can be exploited to measure interface tension. 相似文献