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。
Y2O3:Eu nanocrystals in the size range 70–100 nm have been synthesized with a photoluminescence efficiency 10–20 % higher than that of the commercial bulk material. The Figure shows nanocrystalline Y2O3:Eu after firing of the precursor material. It can be seen that the crystals are structurally perfect, i.e., no defec…
A polycrystalline aluminum sample with a quasi-2D single layer of coarse grains is plastically deformed in a channel die plane strain set-up at ambient temperature and low strain rate. The microtexture of the specimen is determined by analysis of electron back scattering patterns obtained in a scanning electron micros…
The elastic, piezoelectric, and dielectric constants of 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 domain engineered single crystal were determined experimentally by using ultrasonic and resonance methods. It was confirmed that the single crystal system has large electromechanical coupling coefficient k33 (∼94%) and piezoelectri…
We determine, with excellent agreement between theory and experiment, the behavior of single wall carbon nanotubes during uniform electron irradiation. Calculations utilizing known ejection threshold energies predict that an isolated nanotube will damage preferentially on surfaces that lie normal to the electron beam.…
A strong laser pulse that is focused into a liquid produces a vapor cavity, which first expands and then collapses with subsequent rebounds. In this paper a mathematical model of the spherically symmetric motion of a laser-induced bubble is proposed. It describes gas and liquid dynamics including compressibility, heat…
The Clay Minerals Society maintains a repository of Source Clays to provide scientists and researchers with a readily available supply of consistent materials so that research conducted by different groups can be correlated to identical material. These Source Clays include kaolinite, smectite, chlorite, vermiculite, i…
Collagen is the most abundant protein of the organic matrix in mineralizing tissues. One of its most critical properties is its cross-linking pattern. The intermolecular cross-linking provides the fibrillar matrices with mechanical properties such as tensile strength and viscoelasticity. In this study, Fourier transfo…
We propose that the natural tendency of banana-shaped mesogen molecules to induce a local bend of the nematic director can result in pathological elasticity, with negative bend elastic constant. Under this hypothesis, a simple Landau-like phenomenological model predicts a symmetry-breaking transition inside the nemati…
Mesostructured and mesoporous materials are emerging as a new class of optical materials. For mesostructured materials (inorganic/surfactant composites), prepared using a one-step synthesis procedure where the inorganic/surfactant/optically active species coassemble, the unique architecture provided by the surfactant−…
Photoexcitation of a semiconductor with photons above the semiconductor band gap creates electrons and holes that are out of equilibrium. The rates at which the photogenerated charge carriers return to equilibrium via thermalization through carrier scattering, cooling by phonon emission, and radiative and nonradiative…
Fungi make piles of gold! A green-chemistry route, based on the bioreduction of AuCl4− ions by the fungus Verticillium sp., for the formation of gold nanoparticles is demonstrated. The TEM micrograph shows a single Verticillium cell after reaction with gold ions and entrapment of gold nanoparticles on the cell wall an…
We have investigated the key factors determining the performance of supercapacitors constructed using single-walled carbon nanotube (SWNT) electrodes. Several parameters, such as composition of the binder, annealing temperature, type of current collector, charging time, and discharging current density have been optimi…
New morphotropic phase boundary (MPB) piezoelectrics, with ferroelectric phase transition ( T c ) exceeding that of PbZrO 3 –PbTiO 3 (PZT), were investigated. Based on a perovskite tolerance factor- T c relationship, new high T c MPB systems were projected in the Bi(Me)O 3 –PbTiO 3 system, where Me is a relatively lar…
Sonochemical engineering is a field involving the application of sonic and ultrasonic waves to chemical processing. Sonochemistry enhances or promotes chemical reactions and mass transfer. It offers the potential for shorter reaction cycles, cheaper reagents, and less extreme physical conditions, leading to less expen…
This article describes hybrid materials and systems in which the core integrity of inorganic nanobuilding blocks (NBBs) is preserved and reviews the main synthetic procedures presented in the literature. The relation between the NBB and the resulting hybrid networks is discussed for several striking examples: silicon…
Infrared (IR) spectroscopy has a long and successful history as an analytical technique and is used extensively (McKelvy et al. , 1996; Stuart, 1996). It is mainly a complementary method to X-ray diffraction (XRD) and other methods used to investigate clays and clay minerals. It is an economical, rapid and common tech…
Following a seeding growth approach, gold nanoparticles of diameters 5−40 nm were prepared with 10−15% standard deviation in diameter from 3.5 ± 0.7 nm gold particle seeds. Particle size can be controlled by varying the ratio of seed to metal salt, and thus any size in the range 5−40 nm can be prepared. The method can…
We have produced nanotube-in-oil suspensions and measured their effective thermal conductivity. The measured thermal conductivity is anomalously greater than theoretical predictions and is nonlinear with nanotube loadings. The anomalous phenomena show the fundamental limits of conventional heat conduction models for s…
Abstract CEA, in the framework of its research and development activities in support of Liquid Metal Fast Reactors (LMFR), has developed experimental or demonstration plants, now at end of life, which are potential or existing sources of wastes containing sodium. The sodium waste management of CEA forecasts the dispos…
Surface-attached side group liquid crystal polymer monolayers ('brushes') swollen in a nematic solvent were studied by means of dynamic light scattering. In the temperature range 47.5-66°C, the swollen brush is nematic while the bulk liquid crystal is isotropic. Under these conditions the light scattering is dominated…