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。
Molecular dynamics simulations were employed to study atomic motion within stationary and migrating asymmetric tilt grain boundaries. We employ several measures of the ``complexity'' of the atomic trajectories, including the van Hove correlation function, the non-Gaussian parameter, and dynamic entropy. There are two…
The liquid density of Ti–6Al–4V was measured over a temperature range from 1661to1997K that included undercooling by as much as 280K. The sample was levitated in an electrostatic levitator and video imaging technique was used to capture the volume changes as a function of temperature. Over the temperature range the li…
Tribological properties of Ti 3 SiC 2 and Al 2 O 3 ‐reinforced Ti 3 SiC 2 composites (10 and 20 vol% Al 2 O 3 ) were investigated by using an AISI‐52100 bearing steel ball dryly sliding on a linear reciprocating athletic specimen. The friction coefficients were found varying only in a range of 0.1 under the applied lo…
We have measured hard x-ray photoemission spectra of pure vanadium sesquioxide (V(2)O(3)) across its metal-insulator transition. We show that, in the metallic phase, a clear correlation exists between the shakedown satellites observed in the vanadium 2p and 3p core-level spectra and the coherent peak measured at the F…
This second chapter in Part 3 on twinning and domain structures deals with the twinning of crystals in all of its forms: growth twins, transformation twins and deformation twins. The treatment ranges from macroscopic considerations of the geometric orientation relations (twin laws) and the morphology of twins to the m…
Fairly pure ultraviolet (UV) electroluminescence (EL) was realized on a ZnO-based metal-insulator (SiOx,x⩽2)-semiconductor structure on a silicon substrate, which was easily fabricated by the reactive direct current sputtering and electron beam evaporation. The UV EL originated from the near-band-edge (NBE) emission o…
Resonant bending-mode Tb1−xDyxFe2−y∕elastic-steel∕Pb(Zr,Ti)O3 magnetoelectric (ME) laminate composites have been investigated. An elastic-steel layer with a relatively high Qm significantly increases the resonant enhancement of the ME coefficient due to an increased effective Qm of the laminate. The three-phase ME lam…
Abstract Summary: Composite films were prepared from a mixture of poly(vinyl acetate) latex and SWNTs. SEM images reveal a segregated SWNT network that grows heavier with increasing concentration. Nanotube segregation is the result of excluded volume created by the much larger polymer particles in the latex. Thermal c…
This work reports a newly developed synthesis method, i.e., a self-seeding coreduction method , for shape control of silver nanoparticles such as triangular nanoplates and circular nanodiscs. By this method, high surface-to-volume silver nanoplates (∼2.3 nm in thickness) were successfully generated. The distinct advan…
Codoping of Ga and N was utilized to realize p-type conduction in ZnO films using rf magnetron sputtering. The films obtained at 550°C on sapphire showed resistivity and hole concentrations of 38Ωcm and 3.9×1017cm−3, respectively. ZnO films also showed a p-type behavior on p-Si with better electrical properties. ZnO h…
The electrical conductivity and temperature coefficient of resistance of polycrystalline platinum nanofilms have been investigated experimentally and theoretically. The results show that these electrical properties have been greatly reduced mainly by grain boundary scattering. By applying the theory of Mayadas and co-…
The authors demonstrate that the electric conductivities of cubic and hexagonal boron nitride (c-BN and h-BN) thin films increased markedly by the in situ doping of zinc. The doped films were electrically semiconducting, and conductivities at room temperature increased from 10−8to10−2Ω−1cm−1 with increasing zinc conce…
When two or more crystals have the same structure except for the replacement or addition of one or a few (usually heavy) atoms, phase determination using isomorphous replacement can be resorted to. In most practical instances, the atomic form factor is a real number. When the absorption edge of an atom is close to the…
Abstract We consider a solution of the Cahn–Hilliard equation or an associated Caginalp problem with dynamic boundary condition in the case of a general potential and prove that under some conditions on the potential it converges, as t → ∞, to a stationary solution. The main tool will be the Łojasiewicz–Simon inequali…
Nanocomposites are a promising new class of structural materials for the mechanical components of microelectromechanical systems (MEMS). This paper presents a detailed theoretical investigation of the utility of carbon nanotube-reinforced composites for designing actuators with low stiffness and high natural frequenci…
The authors report on the high-performance metal-semiconductor-metal planar photoconductors based on unintentionally doped homoepitaxial diamond thin films. The photoconductors exhibit a discrimination ratio up to 108 between 210nm and visible light. The spectral responsivity at 220nm is about 6A∕W biased at 3V, corre…
Li-doped ZnO films were prepared by pulsed laser deposition. The carrier type could be controlled by adjusting the growth conditions. In an ionized oxygen atmosphere, p-type ZnO was achieved, with the hole concentration of 6.04×1017cm−3 at an optimal Li content of 0.6at.%, whereas ZnO exhibited n-type conductivity in…
We study electron correlation effects on quantum criticalities of Lifshitz transitions at zero temperature, using the mean-field theory based on a preexisting symmetry-broken order, in two-dimensional systems. In the presence of interactions, Lifshitz transitions may become discontinuous in contrast to the continuous…
The authors have quantified the quenching of the luminescence lifetime of Er3+ ions in organic complexes due to the presence of CH vibrational oscillators as a function of their distance from the ion. They have shown that any hydrogen atoms within a sphere of at least 20Å from an erbium ion will cause sufficient quenc…
Three kinds of the response mechanisms to the external pressure have been found for double-walled carbon nanotube (DWCNT) bundle, depending strongly on their average radius and symmetry. The small-diameter DWCNT bundle undergoes a small discontinuous volume change, and then deform continuously. The intermediate-diamet…