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 dynamics of a glassy model with infinite range interactions externally driven by an oscillatory force. We find a well-defined transition in the (temperature-amplitude-frequency) phase diagram between (i) a "glassy" state characterized by the slow relaxation of one-time quantities, aging in two-time quanti…
The electronic ground state and structural and magnetic properties of the pyrite-type antiferromagnetic semiconductor ${\mathrm{MnTe}}_{2}$ have been investigated by combining ${}^{12}\mathrm{Te}$ M\"ossbauer spectroscopy and x-ray-diffraction and electrical resistance measurements at pressures up to 22.5 GPa and temp…
${\mathrm{LaTiO}}_{3.5}$ is a layered compound made up of four ${\mathrm{LaTiO}}_{3}$ units: two regular perovskite units stacked between two distorted units that share an additional oxygen layer. In a single-crystalline thin film the (100) plane can be aligned parallel to the substrate surface, i.e., the additional o…
Density-functional calculations of electronic and magnetic properties of the spinel compound ${\mathrm{ZnFe}}_{2}{\mathrm{O}}_{4}$ done with the general potential linearized augmented plane-wave method are reported. We find significant differences between local spin-density approximation and generalized gradient appro…
Four europium group XIV chalcogenides have been synthesized using the reactive flux method: K(2)EuTSe(5) (I, II) and KEuTS(4) (III, IV) where T = Si, Ge. K(2)EuSiSe(5), I, crystallizes in the monoclinic space group P2(1)/c with cell parameters a = 11.669(3) A, b = 9.844(2) A, c = 8.917(2) A, beta = 91.583(5) degrees,…
During the drying of many polymer films, temperature and compositional changes induce a rubbery−glassy transition at the film surface. The transition front propagates toward the substrate as drying proceeds, eventually rendering the entire coating glassy. The glass transition induces structural changes that have a dir…
Extracting reliable reaction kinetics from nonisothermal calorimetric results can be difficult. The reaction model, activation energy, and frequency factor make up a “kinetic triplet” for a particular reaction and define the reaction kinetics. One expects a good correlation between data and the predictions of the reac…
The catalytic cracking of polyethylene has been studied over two natural clays and their pillared analogues with a view toward assessing their suitability in a process for recycling plastic waste to fuel. Although these clays were found to be less active than US-Y zeolite around 600 K, at slightly higher process tempe…
Self-assembled monolayers (SAMs) of octyltrimethoxysilane (OTMS) were deposited onto indium−tin oxide (ITO) electrode surfaces. Contact angle measurements evidenced the hydrophobicity and homogeneity of the functionalized surface despite the intrinsic surface roughness of the polycrystalline ITO electrodes. The electr…
Carbon nanotubes were suspended in carbon tetrachloride and placed in magnetic fields of <80.0 kOe at 310 K. Scanning electron microscopy showed that a single and free nanotube was oriented with the tube axis parallel to the fields. From the Boltzmann distribution of tube directions, the anisotropy of susceptibilities…
We present numerical support for the hypothesis that macroscopic observables of dense granular media and glasses can be evaluated from averages over typical blocked configurations: we construct the corresponding measure for a class of finite-dimensional systems and compare its predictions for various observables with…
The Mn 2+ impurity luminescence decay of Mn 2+ -doped ZnS nanoparticles has been clearly distinguished from ZnS host emission decay by measuring transient absorption and emission kinetic profiles in the picosecond−millisecond time domain. The Mn 2+ luminescence for the doped sample shows two decay components of 0.18 a…
The design, synthesis, and structural characterization of a highly fluorinated peptide system based on the coiled coil region of the yeast transcription factor GCN4 is described. All four leucine residues (a position) and three valine residues (d position) were replaced by the unnatural amino acids 5,5,5-trifluoroleuc…
We study the effect of temperature up to 1000K on the structure of dense molecular para-hydrogen and ortho-deuterium, using the path-integral Monte Carlo method. We find a structural phase transition from orientationally disordered hexagonal close packed (hcp) to an orthorhombic structure of Cmca symmetry before melti…
High and low temperature relaxation of crystal steps are described in a unified picture, using a continuum model based on a modified expression of the step free energy. Results are in agreement with experiments and Monte Carlo simulations of step fluctuations and monolayer cluster diffusion and relaxation. In an exten…
In this letter, we report the first successful fabrication of dense, metal-clad MgB2 superconductor wires as well as the first demonstration of high transport Jc of greater than 36,000 A/cm2 in MgB2. The fabrication technique that we devised uses only ambient pressure, yet produces very dense MgB2 with little loss of…
We numerically investigate the influence of a homogeneous shear flow on the spinodal decomposition of a binary mixture by solving the Cahn-Hilliard equation in a two-dimensional geometry. Several aspects of this much studied problem are clarified. Our numerical data show unambiguously that, in the shear flow, the doma…
We present a density functional theory for a model colloidal mixture of hard spheres and infinitely thin hard rods. For these freely rotating particles, we use a fundamental measures approach to obtain a functional that features the correct dimensional crossover and the exact low density limit. For isotropic bulk flui…
Wetting or dewetting on soft elastomeric surfaces is largely controlled by the dissipative properties (viscoelasticity) of the substrate. The component of liquid surface tension acting perpendicularly to the solid causes a deformation, or “wetting ridge”, which must be displaced with the triple line. Previously, tripl…
We have employed molecular beam techniques combined with in situ IR reflection absorption spectroscopy to study the CO oxidation kinetics on oxide-supported model catalysts. As model systems we utilize Pd particles of different size and morphology grown under ultrahigh vacuum conditions on a well-ordered alumina film…