Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
We study the effects of $n$-doping and $p$-doping on the structural and electronic properties of $\mathrm{Sr}\mathrm{Ti}{\mathrm{O}}_{3}$ using the ab initio pseudopotential density functional theory. Two types of electron doping and one type of hole doping are considered: introducing O vacancies, substituting V for T…
We model the magnetization of quasi two-dimensional systems with easy perpendicular (z-)axis anisotropy upon change of external magnetic field along z. The model is derived from the Landau-Lifshitz-Gilbert equation for magnetization evolution, written in closed form in terms of the z component of the magnetization onl…
We have studied a non volatile memory effect in the mixed valent compound La$_{0.5}$Ca$_{0.5}$MnO$_{3}$ induced by magnetic field (H). In a previous work [R.S. Freitas et al., Phys. Rev. B 65 (2002) 104403], it has been shown that the response of this system upon application of H strongly depends on the temperature ra…
The surface diffusion of Cu adatoms in the presence of an adisland at FCC or HCP sites on Cu(111) is studied using the EAM potential derived by Mishin {\it et al.} [Phys. Rev. B {\bf 63} 224106 (2001)]. The diffusion rates along straight (with close-packed edges) steps with (100) and (111)-type microfacets (resp. step…
X-ray back diffraction from monolithic two silicon crystal plates of 25--150 um thick and a 40--150 um gap using synchrotron radiation of energy resolution deltaE=0.36 meV at 14.4388 keV shows clearly resonance fringes inside the energy gap and the total-reflection range for the (12 4 0) reflection. This cavity resona…
A first-principles-based scheme is developed to simulate properties of (001) PbO-terminated $\mathrm{Pb}({\mathrm{Zr}}_{1\ensuremath{-}x}{\mathrm{Ti}}_{x}){\mathrm{O}}_{3}$ thin films that are under stress-free and open-circuit boundary conditions. Their low-temperature spontaneous polarization never vanishes down to…
The mechanism for the ferromagnetic order of (Ga,Mn)As and (Ga,Mn)$\mathrm{N}$ is extensively studied over a vast range of Mn concentrations. We calculate the electronic structures of these materials using density functional theory in both the local spin density approximation (LSDA) and the local density approximation…
Using photoemission intensities and a detection system employed by many groups in the electron spectroscopy community as an example, we have quantitatively characterized and corrected detector non-linearity effects over the full dynamic range of the system. Non-linearity effects are found to be important whenever meas…
Mobile applications of hydrogen power have long demanded new solid hydride materials with large hydrogen storage capacities. We report synthesis of a new quaternary hydride having the approximate composition Li(3)BN(2)H(8) with 11.9 wt % theoretical hydrogen capacity. It forms by reacting LiNH(2) and LiBH(4) powders i…
Au and Ag nanoshells are investigated as substrates for surface-enhanced Raman scattering (SERS). We find that SERS enhancements on nanoshell films are dramatically different from those observed on colloidal aggregates, specifically that the Raman enhancement follows the plasmon resonance of the individual nanoparticl…
We present a detailed derivation and thin interface analysis of a phase-field model that can accurately simulate microstructural pattern formation for low-speed directional solidification of a dilute binary alloy. This advance with respect to previous phase-field models is achieved by the addition of a phenomenologica…
A class of highly fluorescent and photostable core-shell nanoparticles from a modified Stober synthesis in the size range of 20-30 nm is described. These nanoparticles are monodisperse in solution, 20 times brighter, and more photostable than their constituent fluorophore, and are amenable to specific labeling of biol…
Highly active and stable substrates for surface-enhanced Raman scattering (SERS) can be fabricated by using colloidal crystals to template gold nanoparticles into structured porous films. The structure-dependent performance of these SERS substrates was systematically characterized with cyanide in continuous flow milli…
Exciton absorption spectra of layered InSe and GaSe crystals electrochemically intercalated by hydrogen were investigated. It was found that the observed at T = 80 K non-monotonic shift of the exciton absorption peak n = 1 with growing hydrogen concentration x (here x is the amount of hydrogen atoms per a formula unit…
Near fully dense ZrO 2 (3Y)/Fe 3 Al composites with significantly improved fracture toughness were synthesized by hot‐press sintering at 1350°C. High fracture toughness and bending‐strength values, 36 MPa·m 1/2 and 1321 MPa, respectively, were achieved in 40 vol% Fe 3 Al composite ceramics, whereas those same values f…
Last decades the enhancement of optical transitions near metal surface was observed under study the optical processes (luminescence, Raman scattering, IR absorption). The effect consists in an essential increase of the intensity of transition (for example, an effective cross-section increases by factor 10 5 10 11 for…
We investigate the experimental detection of the electromagnetic radiation generated in the fast magnetization reversal in Mn 12 -acetate at low temperatures. In our experiments we used large single crystals and assemblies of several small single crystals of Mn 12 -acetate placed inside a cylindrical stainless-steel w…
Electrochemical cells consisting of a La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3−δ (LSCF)–Gd 0.2 Ce 0.8 O 2−δ (CGO) composite catalytic electrode and a CGO solid electrolyte were fabricated for direct nitric oxide (NO) decomposition, and the electrocatalytic properties and NO decomposition behaviors of the cells were investigate…
Microstructural changes during the oxygenation of YBCO bulks were studied. It was shown that a lower temperature of oxygenation leads to the formation of a denser structure of a / b - and c -macrocracks and causes faster and more homogeneous oxygenation of the sample. The opening of created macrocracks is the way in w…
Dense zircon (ZrSiO 4 ) bodies composed of equiaxed grains have been obtained from uniform nanosized powder compacts. The nanosized powders (20 nm in diameter) were prepared by the controlled hydrolysis with ammonium hydroxide of zirconyl chloride and tetraethoxysilane within reverse micelle nanocavities. The crystall…