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。
The effective thermal conductivity of two-dimensional (2D) nanocomposites composed of carbon nanotubes (CNTs) dispersed in a host substrate is simulated to quantify the role of tube percolation on the thermal transport. The model is in excellent agreement with a 2D effective medium theory for low tube densities, but d…
Liquid Ga nanoparticles have been deposited on sapphire substrates at room temperature. The optical evolution of Ga nanoparticle surface plasmon resonance during deposition has been characterized by in situ real-time spectroscopic ellipsometry to control and tune the plasmon resonance photon energy. The existence of b…
The authors have performed a systematic computational study of the hydrogen storage capacity of model organometallic compounds consisting of Sc, Ti, and V transition metal atoms bound to CmHm rings (m=4-6). For all the complexes considered, the hydrogen storage capacity is limited by the 18-electron rule. The maximum…
The authors report the temperature dependence of the near-infrared photoluminescence (PL) emission from thiol-capped PbS quantum dots. The high thermal stability of the PL allows the authors to study the thermal broadening of the dot emission over an extended temperature range (4–300K). The authors show that the linew…
Abstract Biodegradable thermoplastic‐based composites reinforced with kenaf fibers were prepared and characterized. Poly(3‐hydroxybutyrate‐ co ‐3‐hydroxyvalerate) (PHBV), produced by bacterial fermentation, was selected as polymeric matrix. To improve PHBV/fibers adhesion, low amount of a proper compatibilizing agent,…
Single-walled carbon nanotubes (SWNTs) are considered as promising filler materials for improving the thermal conductivity of conventional polymers. We carefully investigated the thermal conductivity of SWNT poly(methylmethacrylate) (PMMA) nanocomposites with random SWNT orientations and loading up to 9vol% using the…
Vertically aligned ZnO nanowire arrays are grown homoepitaxially on the ZnO seeded indium tin oxide substrate by electrochemical deposition from aqueous solution at low temperature (70°C) without using any template. ZnO nanowires exhibit single crystalline, wurtzite crystal structure determined by transmission electro…
Abstract Liquid transport and movement in yarns were studied using an experimental system based on the analysis of charge couple device images taken during the capillary rise of a colored liquid in the yarn. The generalized dynamic model of the liquid penetration into vertical cylindrical capillary used was based on t…
In this letter the authors show the structure transformation from distorted spinel Mn3O4 to layered structure birnessite by cyclic voltammetry (CV) cycling in aqueous Na2SO4 using the high temperature (900°C) treated manganese oxide film as the electrode. The process is a dynamic-potential activated procedure, which c…
Theoretical ab initio and experimental methods are used to investigate the $[\mathrm{Bi}({\mathrm{Zn}}_{1/2}{\mathrm{Ti}}_{1/2}){\mathrm{O}}_{3}{]}_{x}\phantom{\rule{0ex}{0ex}}[{\mathrm{PbTiO}}_{3}{]}_{1\ensuremath{-}x}$ solid solution. We find that hybridization between Zn $4s$ and $4p$ and O $2p$ orbitals allows the…
The annealing effects on magnetism, structure, and ac transport for Co:ZnO films have been systematically investigated. The room temperature saturation magnetization (Ms) varies drastically with Ar or Ar∕H2 annealing processes. By using the impedance spectra, the change in grain boundary and grain defects of these fil…
Dielectric relaxations of Ba(Fe1∕2Ta1∕2)O3 ceramics were investigated and discussed over a broad temperature and frequency range. Two dielectric relaxations following Arrhenius law were observed at 153–382 and 440–623K, where there was a giant dielectric constant step between them. The frequency dependent rapid drop o…
Abstract The effectiveness of four different reagents, glutaraldehyde (GTA), 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC), poly(ethyelene glycol) diglycidyl ether (EX 810), and divinyl sulfone (DVS) as crosslinkers for cast hyaluronic acid (HA) films has been evaluated. Films were prepared by casting from solu…
We study anharmonic effects in MgB2 by comparing Inelastic X-ray and Ramanscattering together with ab-initio calculations. Using high statistics and high q resolution measurements we show that the E2g mode linewidth is independent of temperature along Gamma-A. We show, contrary to previous claims, that the Raman-peak…
Recent experiments by Venkatamaran {\em et al.} [Nature (London) {\bf 442}, 904 (2006)] on a series of molecular wires with varying chemical compositions, revealed a linear dependence of the conductance on $\mathrm{cos}^2θ$, where $θ$ is the angle of twist between neighboring aromatic rings. To investigate whether or…
The authors used depth-resolved cathodoluminescence spectroscopy and current-voltage measurements to probe metal-ZnO diodes as a function of native defect concentration, oxygen plasma processing, and metallization. The results show that resident native defects in ZnO single crystals and native defects created by the m…
The three invariants of C$^{1/2}$ are key to expressing this tensor and its inverse as a polynomial in C. Simple and symmetric expressions are presented connecting the two sets of invariants $I_1, I_2,I_3$ and $i_1, i_2,i_3 $ of C and C$^{1/2}$, respectively. The first result is a bivariate function relating $I_1, I_2…
The effect of Mg substitution on the crystal structure of wurtzite ZnO is presented based on synchrotron x-ray diffraction studies of polycrystalline Zn1−xMgxO (⩽x⩽0.15). Increase in Mg concentration results in pronounced c-axis compression of the hexagonal lattice, and in diminution of the off-center cation displacem…
This experimental PhD work deals with the generation and transformation processes of point defects induced by UV laser irradiation on amorphous silicon dioxide (silica). The investigation relies on several spectroscopic techniques used to probe the microscopic damage induced by UV laser on the material. The most innov…
The authors report a synthesis of unique superhard aggregated boron nitride nanocomposites (ABNNCs) showing the enhancement of hardness up to 100% in comparison with single crystal c-BN. Such a great hardness increase is due to the combination of the Hall-Petch and the quantum confinement effects. The decrease of the…