Materials Literature
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We present ab initio calculations of the magnetic susceptibility and of the $^{13}\mathrm{C}$ chemical shift for carbon nanotubes, both isolated and in bundles. These calculations are performed using the recently proposed gauge-including projector augmented-wave approach for the calculation of magnetic response in per…
The high-pressure behavior of ${\mathrm{Ga}}_{2}{\mathrm{O}}_{3}$ is studied up to $40\phantom{\rule{0.3em}{0ex}}\mathrm{GPa}$ using synchrotron x-ray diffraction and Raman spectroscopy in diamond anvil cells. A phase transformation from the monoclinic $\ensuremath{\beta}$-phase $(C2∕m)$ is observed at a pressure abov…
For a previously published study of the titanium hexagonal close packed $(\ensuremath{\alpha})$ to omega $(\ensuremath{\omega})$ transformation, a tight-binding model was developed for titanium that accurately reproduces the structural energies and electron eigenvalues from all-electron density-functional calculations…
Based on density functional perturbation theory, we have studied the vibrational properties of three crystalline phases of tellurium dioxide: paratellurite $\ensuremath{\alpha}\text{\ensuremath{-}}{\mathrm{TeO}}_{2}$, tellurite $\ensuremath{\beta}\text{\ensuremath{-}}{\mathrm{TeO}}_{2}$, and the new phase $\ensuremath…
X-ray photoemission spectroscopy has been used to investigate the depth dependent crystal structures and chemical compositions of sequentially chemical-etched YBa2Cu3O7-d (YBCO) ultrathin film superconductors. In the near-interface region the crystal structure is severely oxygen deficient and of tetragonal symmetry. W…
The synthesis, structure, and characterization of a new noncentrosymmetric molybdenum tellurite, Na 2 Te 3 Mo 3 O 16, are reported. Na 2 Te 3 Mo 3 O 16 crystallizes in the noncentrosymmetric monoclinic space group I 2 (No. 5, cell choice 3) with a = 7.3373(10) Å, b = 11.2668(16) Å, c = 8.2369(18) Å, and β = 97.387(3)°…
”Systematic errors”, namely, oxygen vacancy sites in ZnO, are the active centers for the hydrogenation of CO to give methanol. Nanocrystalline ZnO with a high density of oxygen vacancies was prepared from special organometallic precursors, and its catalytic properties for methanol synthesis were studied.
Using in situ high-resolution synchrotron x-ray scattering, the Curie temperature TC has been determined for ultrathin c-axis epitaxial PbTiO3 films on conducting substrates (SrRuO3 on SrTiO3), with surfaces exposed to a controlled vapor environment. The suppression of TC was relatively small, even for the thinnest fi…
Lead‐free Na 0.5 K 0.5 NbO 3 (NKN) piezoelectric ceramics were fairly well densified at a relatively low temperature under atmospheric conditions. A relative density of 96%–99% can be achieved by either using high‐energy attrition milling or adding 1 mol% oxide additives. It is suggested that ultra‐fine starting powde…
The influence of electrode material, dc bias, and pellet thickness on the electrical properties of fine- and coarse-grained $\mathrm{Ca}{\mathrm{Cu}}_{3}{\mathrm{Ti}}_{4}{\mathrm{O}}_{12}$ (CCTO) ceramics has been investigated using impedance spectroscopy. The low frequency arc observed in ${\mathrm{Z}}^{*}$ plots nea…
Here we report the synthesis, structure, and optical properties of ca. 100 nm star-shaped gold nanoparticles. Single particle spectroscopy measurements revealed that these nanoparticles have multiple plasmon resonances resulting in polarization-dependent scattering with multiple spectral peaks, which correspond to the…
Abstract The study on the dynamic viscoelastic properties of grafted carbon black ( g ‐CB) filled low‐density polyethylene (LDPE) was carried out. Because of formation of CB networking, the characteristic modulus plateau and loss tangent arc appears. Addition of grafting monomer like butyl acrylate (BA) and acroleic a…
Abstract Polychloroprene is a diene rubber, but unlike other diene rubbers, its compounding with various additives and curing mechanisms is different. A derivative of thiourea, ethylene thiourea (ETU), is widely used to vulcanize chloroprene rubber (CR), and the vulcanizates thus obtained exhibit excellent mechanical…
Abstract A triarylpyrylium ion containing iodo and biphenyl substituents has been synthesized and its photophysical properties measured. Compared to its parent triphenylpyrylium ion,the photophysical data recorded for 4‐(biphenyl‐4‐yl)‐2,6‐bis(4‐iodophenyl)pyrylium are significantly influenced by substitution. Remarka…
Controlled reversible changes in surface texture and topography are of interest to many applications, including information storage, optical communication devices, micro-fluidic instruments for drug delivery, and smart tribological surfaces for friction and wear control. Here, we demonstrate a method of inducing two-w…
We describe the preparation of $\mathrm{Se}\mathrm{Co}{\mathrm{O}}_{3}$ under moderate pressure conditions $(3.5\phantom{\rule{0.3em}{0ex}}\mathrm{GPa})$, starting from reactive $\mathrm{Se}{\mathrm{O}}_{3}{\mathrm{H}}_{2}$ and MO mixtures, contained in sealed gold capsules under the reaction conditions ($850\phantom{…
Abstract A complex consisting of one Bi 3+ ion and two 2‐mercaptoethanol units (BiME 2 ) was used as initiator for the ring‐opening polymerization of ε‐caprolactone in bulk. A kinetic comparison showed that BiME 2 is as reactive as initiator as Sn‐octanoate and more reactive than Bi‐hexanoate. The difference to BiHex…
Atomic resolution high-angle annular dark field (HAADF) imaging in scanning transmission electron microscopy was used to investigate the interface atomic structure of epitaxial, (111) oriented SrTiO3 films on epitaxial Pt electrodes grown on (0001) sapphire. The cube-on-cube orientation relationship of SrTiO3 on Pt wa…
Density functional theory has been used to determine the interface structure and energy of Pt films on both ideal terminations of the polar $\mathrm{La}\mathrm{Al}{\mathrm{O}}_{3}(100)$ surface. $\mathrm{La}\mathrm{Al}{\mathrm{O}}_{3}(100)$ surfaces on bulk $\mathrm{La}\mathrm{Al}{\mathrm{O}}_{3}$ are compared to stra…
Abstract The initial oxidation of magnesium at oxygen partial pressures between 1.3 × 10 −8 and 1.3 × 10 −5 Pa and at temperatures ranging from 273 to 550 K has been investigated in situ with X‐ray photoelectron spectroscopy (XPS), ellipsometry and high resolution elastic recoil detection analysis (HERDA). Quantitativ…