Materials Literature
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Equilibrium swelling and phase behavior of liquid crystalline (LC) networks swollen in miscible nematogenic solvents has been investigated by polarizing microscopy as a function of temperature. Four systems, i.e., each of two different LC networks comprising dissimilar mesogens in two different nematic solvents, exhib…
Electronic and magnetic properties of MnN and MnAs compounds in the hypothetical cubic zinc-blende phase are studied using first-principles band structure method. We show that the high electronegativity and small atomic size of N compared to As lead to interesting consequences: MnN has a low-spin antiferromagnetic gro…
We have investigated charge carrier transport in the smectic mesophases of a liquid crystal, i.e., a 2-phenylnaphthalene derivative, by computational Monte Carlo simulation and time-of-flight experiments. The unique carrier transport properties characterized by field-independent high mobility over 10−3 cm2/V s observe…
Abstract The results of thermoelectric power ( S ) measurements of the lead chalcogenides PbS, PbSe, and PbTe at the initial NaCl‐phase, as high‐pressure semiconductors (above 2–6 GPa), and at metal phases (above 10–15 GPa) are presented. Phase transitions are discussed in terms of the model of Peierls distortion of l…
Electronic properties of single Pd atoms, deposited on Al(2)O(3)/NiAl(110), have been characterized by scanning tunneling spectroscopy at 12 K. The spectra reveal distinct conductivity resonances, assigned to discrete electronic levels in the atom. The energy position of the resonances reflects adsorption properties o…
Electrons in chains: A novel metallic chain made up of six iridium atoms (see picture) with an average oxidation state of +1.33 has been found in the complex HH,HT,HH-[Ir6(μ-OPy)6(I)2(CO)12] (Opy=2-pyridonate, H=head, T=tail). This complex provides a new link in the electronic sequence connecting dinuclear IrI and IrI…
We report on the fabrication of nanometer-scale mechanical devices incorporating multiwalled carbon nanotubes (MWNTs) as the torsional spring elements. We have employed electron beam lithography to pattern device elements directly onto individual MWNTs on a silicon dioxide substrate. The structures were suspended by e…
We report on site-selective growth of multiwalled carbon nanotubes (MWNTs) from a Co nanoparticle catalyst patterned by an ink-jet printing (IJP) technique. The dispersion of the Co nanoparticles was employed as “catalyst ink” for the IJP, and the catalyst pattern was subjected to chemical vapor deposition of acetylen…
Abstract Catalysts of Co,K/La 2 O 3 have been prepared by wet impregnation. The samples have been calcined at 400°C and 700°C and have been characterized for phase composition using x‐ray diffraction and Fourier transform infrared spectroscopy. The XPS analysis of the samples has been obtained by examination of the O…
The Mg 2 Ni intermetallic compound was successfully prepared under 3.00 MPa hydrogen pressure at 553 K from magnesium and nickel ultrafine particles, which were obtained from a hydrogen plasma–metal reaction. A thermal treatment process under vacuum was used to obtain Mg 2 Ni. The nanometre-scale effect is thought to…
We have demonstrated assembly of two- and three-dimensional networks of single-walled carbon nanotubes (SWNTs) using a microsphere assembly approach. The catalyst microcapsules are made from the solution based impregnation of uniform diameter, porous polystyrene microspheres. Chemical vapor deposition on the microcaps…
Thin-film solid solutions of SmxNd1−xNiO3 were synthesized on NdGaO3 substrates by pulsed-laser deposition using alternating NdNiO3 and SmNiO3 targets. The films were characterized by x-ray diffraction and variable-temperature four-probe conductivity measurements. The films grow in the {100}pseudocubic direction. Ther…
Abstract Considerable attention has been devoted recently to the dependence of the widths of the Raman phonons of semiconductors on pressure and on isotopic mass. The dependence on pressure is usually small and monotonic unless the phonon happens to be close to a singularity of the two‐phonon density of states (DOS) w…
Abstract In this study sulphur hexafluoride (SF 6 ) plasmas and argon plasma immersion ion implantation (ArPIII) techniques have been applied to improve the hydrophobicity of poly(tetrafluoroethylene) (PTFE), polyurethane and silicone surfaces. As evaluated by water contact angle measurements, all the treatments resul…
Based on the model of lattice dynamics with force-constant matrix, we have calculated phonon spectrum and then specific heats of single-walled carbon nanotubes. The results show that with a more complicated phonon spectrum, a single-walled carbon nanotube has analogous good thermal conductivity to the two-dimensional…
The structure, resistivity, thermopower, and magnetic behaviors of two sets of samples ${\mathrm{CaMn}}_{1\ensuremath{-}x}{\mathrm{Ru}}_{x}{\mathrm{O}}_{3}$ and ${\mathrm{CaMn}}_{1\ensuremath{-}y}{\mathrm{Mo}}_{y}{\mathrm{O}}_{3}$ $(0.04<~x<~0.08;$ $0.02<~y<~0.04)$ have been studied. All samples exhibit a…
Ab initio electronic structure calculations of the ideal strength of Fe, Co, Ni, and Cr under isotropic tension were performed using the linear muffin-tin orbital method in the atomic sphere approximation. Magnetic ordering was taken into account by means of a spin-polarized calculation. Two approximations for the exc…
We examine the favored cluster structures for two new interatomic potentials, which both behave as monatomic model glass formers in bulk. We find that the oscillations in the potential lead to global minima that are noncompact arrangements of linked 13-atom icosahedra. The structural properties of the clusters correla…
BN nanotubes are coated with SnO(2) by a simple chemical reaction in solution. BN nanotubes are stirred inside a SnCl(2) solution at room temperature for 1 h. The coating is uniform with complete coverage. The coating thickness is typically 1-5 nm. The coating layer contains SnO(2) nanoparticles with sizes ranging fro…
Dynamics of supercooled ortho-terphenyl, salol, benzophenone, 2-biphenylmethanol, and dibutylphthalate have been studied using optical heterodyne detected optical Kerr effect experiments over a broad range of time, &lt;1 ps to tens of ns. On time scales longer than those influenced by intramolecular vibrational dy…