Materials Literature
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A rapid-compression apparatus with a large pressure jump is described. The pressure jump was performed principally by using a large volume bladder-type power accumulator that contains compressed nitrogen and the connected electromagnetic valves. Maximum force induced by the press is 1.1 MN. Within 20 ms the pressure o…
Symmetrically substituted oligophenylenevinylene (OPV) derivatives bearing terminal p-nitrophenylhydrazone groups have been prepared and used for the synthesis of dumbbell-shaped bis(pyrazolino[60]fullerene)-OPV systems. In these triad arrays, the OPV-type fluorescence is dramatically quenched as a consequence of ultr…
An atomic force microscope was used to locally perturb and detect the charge density in carbon nanotubes. Changing the tip voltage varied the Fermi level in the nanotube. The local charge density increased abruptly whenever the Fermi level was swept through a van Hove singularity in the density of states, thereby coup…
We have investigated the miscibility and hydrogen-bonding behavior of ternary blends of phenoxy, phenolic, and poly(ε-caprolactone) (PCL) by using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy. On the basis of DSC analyses, we observed a rare totally miscible ternary hydrogen-bond…
Capacitance-voltage (C–V) measurements were performed on epitaxial layers of Pb(Zr0.2Ti0.8)O3 (PZT) with top and bottom SrRuO3 (SRO) electrodes. It is shown that the sharp capacitance peak∕discontinuity which is present in the C–V characteristics at different frequencies is directly associated with the polarization re…
A novel aerobic benzoate pathway has recently been discovered in various bacteria in which benzoate is first converted to benzoyl-CoA. The further downstream steps are associated with the gene products of the benzoate oxidation gene cluster (box) on the Azoarcus evansii chromosome. Benzoyl-CoA is oxidized to 2,3-dihyd…
The energies of the $5d$ excited states of ${\mathrm{Ce}}^{3+}$ and ${\mathrm{Pr}}^{3+}$ impurities relative to the conduction band of the insulators ${\mathrm{Y}}_{2}\mathrm{Si}{\mathrm{O}}_{5}$ and ${\mathrm{Lu}}_{2}\mathrm{Si}{\mathrm{O}}_{5}$ were investigated through a temperature and spectrally resolved photocon…
Rigid-rod dendronized linear polymers consisting of a poly(4-hydroxystyrene) backbone and fourth-generation polyester dendrons were evaluated in vitro and in vivo to determine their suitability as drug delivery vectors. Cytotoxicity assays indicated that the polymers were well tolerated by cells in vitro. Biodistribut…
Local piezoelectric deformation is investigated in (Pb,La)TiO3 (PLT) and Pb(Zr,Ti)O3 (PZT) thin films via scanning force microscopy (SFM) as a function of the ac voltage Vac applied between the conducting tip and the bottom electrode. Thus obtained voltage dependence of the effective piezoelectric coefficient (local p…
Low dimensional (nanowall) ZnO structures were prepared by a two-step growth method with oxygen-plasma-assisted molecular beam epitaxy, where the as-grown film was first engraved on a porous template using the oxygen plasma and then the ZnO nanowalls were grown on the template. The resonance Raman spectra showed the s…
We present results of detailed investigation of the crystal structure of Pb1−3x/2Lax(Zr1−yTiy)O3 solid solutions. In this letter our attention is concentrated on the series of solid solutions with x = 6% usually referred to as relaxor ferroelectrics. We have established the reasons for the non-cubic crystal structure…
The helical structure of uniformly aligned chiral nematic liquid crystals results in a photonic stopband for only one sense of circular polarization. The spectroscopic Stokes polarimeter is used to analyze spontaneous emission in the stopband. Highly polarized photoluminescence is found and the polarization properties…
Knowledge of the viscosity and its temperature dependence is essential to improve metallurgical processes as well as to validate theoretical and empirical models of liquid metals. However, data for metals with melting points above 2504K could not be determined yet due to contamination and containment problems. Here we…
Quaternary Heusler alloy Ni50Mn8Fe17Ga25 ribbons have been prepared by the melt-spun method. The ribbons exhibit large negative magnetoresistance (MR){=[R(H)−R(0)]∕R(0)} over a wide temperature region, particularly in the region during the martensitic phase transformation. The MR decreases significantly after annealin…
We report the preparation of ZnO nanocrystals embedded in a SiO2 matrix formed using sequential zinc and oxygen ion implantations. The optical absorption spectra and photoemission spectra of zinc implanted and zinc/oxygen coimplanted silica show that the first zinc implantation produces zinc clusters and that the subs…
Dielectric properties of water adsorbed in pure siliceous and aluminium containing mesoporous MCM-41 materials have been investigated in the frequency range from 20 Hz to 1 MHz. The dielectric spectra revealed three dispersion regions, liquid-like free water in the centre of the mesopores, an intermediate water layer…
Electromagnetic waves in an artificial medium formed by two mutually orthogonal lattices of thin ideally conducting straight wires (referred to as a two-dimensional wire medium) are considered. An effective medium approach and a full-wave method based on the dyadic Green's function and the method of moments are develo…
Thin films of layered ferroelectric oxide Bi5FeTi3O15 have been fabricated on Pt-coated Si substrates by pulsed laser deposition. Temperature-dependent Raman studies reveal the phase-transition temperature of 550 °C, consistent with other reports. A new mode at 685cm−1 is observed and ascribed to the Bi–Fe–O perovskit…
The effects of nonequally biaxial in-plane misfit strains on the equilibrium polarization states and the dielectric properties of single-domain epitaxial ferroelectric thin films are investigated by a nonlinear thermodynamic theory. The “misfit strain-misfit strain” and “temperature-misfit strain” phase diagrams for s…
The detection of nanotube carbons in solution by (13)C NMR is reported. The highly soluble sample was from the functionalization of (13)C-enriched single-walled carbon nanotubes (SWNTs) with diamine-terminated oligomeric poly(ethylene glycol) (PEG(1500N)). The ferromagnetic impurities due to the residual metal catalys…