Materials Literature
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Abstract As shown by N. Engheta, electromagnetic fields in two adjacent slabs bounded by two metal walls can satisfy the boundary conditions, even if the distance between the two walls is much smaller than the wavelength. This is possible if one of the slabs has a negative permeability. Here we show that these subwave…
Simultaneous measurements of Raman spectroscopy and synchrotron two-dimensional (2D) wide-angle x-ray diffraction (WAXD) have been successfully demonstrated for in situ study of an anisotropic system: isotactic polypropylene (iPP) fiber under tensile deformation. A fiber-optic probe was used to remotely deliver the in…
The dielectric strength of films made from poly(ethylene terephthalate) (PET) coated with a thin layer of polyaniline (PANI) was studied. The PANI layer was deposited on the PET films by the ` in situ ' chemical polymerization method. The PANI layer of the PANI/PET films was undoped in NH 4 OH 0.1 M solution and re-do…
The tensor components of the electric dipole polarizability at a wavelength of 632.8 nm, those of the magnetizability and the anisotropy of the static hypermagnetizability of furan, thiophene, and selenophene are computed using density functional theory (DFT). The polarizable continuum model (PCM) is employed to descr…
An ultrahigh vacuum three-axis cryogenic sample manipulator suitable for angle-resolved photoelectron spectroscopy experiments was developed. The sample manipulator is constructed by combining three modules with translation, polar rotation, and azimuthal-tilt rotation capabilities. Polar rotation and the azimuthal-til…
A simple reactive evaporation method is proposed to prepare light-emitting amorphous SiOx thin films. By evaporating pure silicon in a controlled molecular oxygen atmosphere, it is possible to obtain a very large composition range. By changing the pressure in the preparation chamber, x can be varied from 0.7 to 1.85.…
Abstract The rate constants of cross reactions in the copolycondensation of bis(3‐hydroxypropyl)terephthalate (BHPT) and bis(2‐hydroxyethyl)terephthalate (BHET), k 12 and k 21 , were determined with the results obtained from 1 H NMR spectroscopy analysis. BHPT and BHET were polymerized and copolymerized at 260, 270, a…
The thermodynamic and kinetic anomalies of supercooled liquids are analyzed from the perspective of energy landscapes. A mean-field model, a generalized random energy model of liquids, is developed which exhibits a dynamical transition of the onset of slow dynamics at T0, alteration of the nature of motion from saddle…
This contribution presents results of kinetic studies of the isomerization of photochromic 4-fluoro-4‘-methoxyazobenzene dissolved in the liquid-crystalline pentylcyanobiphenyl (5CB). Deviations from the expected Arrhenius behavior were observed for the thermal cis − trans reaction near the phase transition temperatur…
A semianalytic theory is developed for calculating percolation thresholds for rod-like nanoparticles dispersed in a flexible polymeric matrix. Methods of macromolecular integral equation theory are combined with the connectedness Ornstein–Zernike equation and an explicitly two-component model in which both the molecul…
Abstract The objective of this study was the development of new vinyl flooring formulations with increased resistance to attack by fungi and microorganisms, formulated with plasticizers having chemical compositions different from that of common dioctyl phthalate (DOP). Alkyl phthalate plasticizers are considered to be…
Abstract The effect of CO 2 on the nonisothermal crystallization of isotactic polypropylene (iPP) was studied with high‐pressure differential scanning calorimetry at cooling rates of 0.2–5 °C/min. CO 2 significantly delayed the melt crystallization of iPP, and both the crystallization temperature and the heat of cryst…
We confirm by Monte Carlo simulations of a Lebwohl-Lasher lattice spin model the existence of a biaxially ordered nonbent structure in a liquid-crystalline cell subject to opposing boundary conditions. We report on the observation of the bending transition from the biaxial to the bent-director structure when the tempe…
A nonthermal plasma process (dielectric-packed bed reactor) was combined with catalyst to remove nitrogen oxides (NO x ). Two different honeycomb catalysts such as V 2 O 5 /TiO 2 and Cr 2 O 3 /TiO 2 were compared with respect to the removal characteristic of NO x . The effect of oxygen content, water vapor, feed gas f…
Abstract Changes in the lamellar and crystalline structures were followed as a function of applied stress to understand the influence of the interactions between the crystalline and amorphous domains on the fiber properties. We observed a reversible transformation from a structure giving a four‐point small‐angle patte…
Electrically conducting redox-active particles were synthesized by coating near-monodisperse, micrometer-sized polystyrene latex particles (1.62 μm diameter) with polyaniline at 0 °C. This low-temperature synthesis route ensured that high-quality polyaniline was produced. The purified particles were dispersed in an aq…
Inclusion complexation of beta-chitin with linear aliphatic amines was studied by X-ray diffraction. All tested amines, C3 to C8 monoamines and C2 to C7 diamines with terminal amino groups, reversibly formed crystalline complexes with beta-chitin by immersion of dry chitin in pure liquid. Complex formation caused line…
In this paper, we set forth a general theoretical framework to predict the nanoelectromechanical behavior of polyelectrolyte brushes and then apply it to a model system of negatively charged chondroitin sulfate glycosaminoglycan (CS-GAG) chains. We used a Poisson−Boltzmann (PB) based approach to calculate the electros…
An intracellular 3-hydroxybutyrate (3HB)-oligomer hydrolase (PhaZ2(Reu)) of Ralstonia eutropha was purified from Escherichia coli harboring a plasmid containing phaZ2(Reu). The purified enzyme hydrolyzed linear and cyclic 3HB-oligomers. Although it did not degrade crystalline poly(3-hydroxybutyrate) (PHB), the purifie…
We report scanning tunneling microscopy of semiconductor-semiconductor carbon nanotube junctions with different band gaps. Characteristic features of the wave functions at different energy levels, such as a localized defect state, are clearly exhibited in the atomically resolved scanning tunneling spectroscopy. The pe…