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。
Findings are presented from a systematic study of the effects of postdeposition thermal treatment on the optical characteristics of hydrogenated amorphous silicon-oxycarbide (a-SiCxOyHz) materials. Three different classes of a-SiCxOyHz films: SiC-like (SiC1.08O0.07H0.21), Si-C-O (SiC0.50O1.20H0.22), and SiO2-like (SiC…
We report the investigations of crystal structure, electrical resistivity (ρ), magnetization (M), x-ray photoelectron spectroscopy (XPS), specific heat (CP), thermal conductivity (κ), and thermoelectric power (TEP) on La0.7Sr0.3(Mn1−xRux)O3 (LSMRO) compounds with x=0 to 0.90. From the analyzes of crystal structure and…
Eu 3 + -doped transparent nano-glass-ceramics, 32(SiO2)9(AlO1.5)31.5(CdF2)18.5(PbF2)5.5(ZnF2):3.5(EuF3)mol %, have been prepared aiming at the investigation of the site structure of the Eu3+ rare-earth dopant. In this nano-glass-ceramic host, other rare-earth dopants, such as Er3+, Tm3+, Ho3+, and Dy3+, also have serv…
The magnetic microstructure of thermomechanically processed (die-upset) melt-spun NdFeB magnets with different degrees of texture in thermally demagnetized and in dc-demagnetized states has been investigated systematically using magnetic force microscopy. An isotropic magnetic microstructure with a fine contrast on a…
p -type ZnO thin films with significantly reduced band gaps were synthesized by heavy Cu incorporation at room temperature and followed by postdeposition annealing at 500°C in air for 2h. All the films were synthesized by rf magnetron sputtering on F-doped tin oxide-coated glass. The p-type conductivity was confirmed…
We propose an experimental scheme to simulate and observe relativistic Dirac fermions with cold atoms in a hexagonal optical lattice. By controlling the lattice anisotropy, one can realize both massive and massless Dirac fermions and observe the phase transition between them. Through explicit calculations, we show tha…
We propose a technique for achieving large improvements in carrier mobilities in 2- and 1-dimensional semiconductor nanostructures by modifying their dielectric environments. We show that by coating the nanostructures with high-$κ$ dielectrics, scattering from Coulombic impurities can be strongly damped. Though screen…
We report microstructural characteristics and properties of gallium-doped ZnO films deposited on glass by pulsed laser deposition. The Zn0.95Ga0.05O film deposited at 200 °C and 1×10−3 Torr showed predominant ⟨0001⟩ orientation with a metallic behavior and a resistivity of 2×10−4 Ω cm at room temperature. Low resistiv…
The outstanding piezoelectric properties of lead zirconate titanate (PZT) ceramics with compositions close to the morphotropic phase boundary of the quasibinary phase diagram of lead zirconate and lead titanate are still under debate. A combination of ex situ and in situ transmission electron microscopy and high resol…
Our investigations into the ZnO–TeO2 system have produced a new phase, zinc(II) hexatellurium(IV) tridecaoxide, ZnTe6O13, with trigonal (R\overline{3}) symmetry, synthesized by repeated heating and cooling to a maximum temperature of 1053 K. The asymmetric unit consists of a Zn atom coordinated in a distorted octah…
The title compound, lithium tris[dioxidovanadium(V)] bis[trioxidotellurium(IV)], contains chains of edge-sharing distorted VO(6) octahedra. The pyramidal TeO(3) groups crosslink the chains into sheets. Finally, an Li(+) cation adopting an unusual capped trigonal-bipyramidal LiO(6) geometry bridges the layers to comple…
This work aims to experimentally determine the polarizability of confined electron in CdSe quantum dots (QD). The dielectric response of uncharged and charged CdSe quantum dots (3.2 and 6.3 nm) has been measured using terahertz time-domain spectroscopy in the frequency range of 2.0-7.0 THz. A strong coupling between t…
Abstract Thermal-swing extraction of CdII with a thermosensitive gel, poly(N-isopropylacrylamide) (NIPA) crosslinked with an encapsulating ligand, N,N,N′,N′-tetrakis(4-propenyloxy-2-pyridylmethyl)ethylenediamine (TPPEN), was examined. CdII was extracted in the gel swollen at 5 °C and released from the gel shrunken at…
The direct synthesis of hydrogen peroxide (H 2 O 2 ) from H 2 and O 2 over gold nanoparticles has been achieved in the past decade; however, our understanding for the mechanism is still far from complete. We present herein a density functional theory investigation of the formation mechanism of H 2 O 2 from H 2 and O 2…
We report on a new high-resolution optical spectroscopy, coherent phonon measurement, for determining the chiral index of carbon nanotubes. Using femtosecond pump-probe spectroscopy, we demonstrate the real-time observation of lattice vibrations in individualized single-walled carbon nanotubes in an aqueous surfactant…
The structure of a new layered oxyfluoride, viz. potassium strontium diniobium hexaoxide fluoride, KSrNb(2)O(6)F, was refined from powder neutron diffraction data in the orthorhombic space group Immm. The oxyfluoride compound is an n = 2 member of the Dion-Jacobson-type family of general formula A[A'(n-1)B(n)X(3n+1)],…
Abstract The use of chromate baths is being progressively restricted owing to the high toxicity of the hexavalent chromium (Cr6+) compounds. In this work, chemical conversion coating on AZ31 (3% Al, 1% Zn) magnesium alloy was performed by immersion in 5 mM Ce(NO3)3 solution with and without addition of Al(NO3)3 and Ca…
Abstract Pillared carbons containing silica between their carbon layers were first prepared by the pyrolysis of graphite oxide silylated by 3-aminopropyldiethoxymethylsilane between 450 and 550 °C under vacuum. They possessed both microporosities and mesoporosities existing between their carbon layers.
Cationic porphyrins have an affinity for DNA and potential for applications in the fields of photodynamic therapy and cellular imaging. This report describes a new dicationic porphyrin, 5,15-dimethyl-10,20-di(N-methylpyridinium-4-yl)porphyrin, abbreviated H2tMe2D4. Although tetrasubstituted, H2tMe2D4 presents modest s…
meso-Pyrimidinyl-substituted A2B-corroles were synthesized in good yields by condensation of 5-mesityldipyrromethane and 2-substituted 4,6-dichloropyrimidine-5-carbaldehydes. A simple reduction of the amount of Lewis acid (BF3.OEt2) resulted in the formation of A2B-corroles, which was optimized to maximize the corrole…