Materials Literature
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We derive a phenomenological continuum saltation model for aeolian sand transport that can serve as an efficient tool for geomorphological applications. The coupled differential equations for the average density and velocity of sand in the saltation layer reproduce both known equilibrium relations for the sand flux an…
A self-consistent calculation of the electronic properties of GaAlAs:Mn magnetic semiconductor quantum well structures is performed including the Hartree term and the sp-d exchange interaction with the Mn magnetic moments. The spin polarization density is obtained for several structure configurations. Available experi…
One-dimensional quasilattices, namely, the geometrical objects to represent quasicrystals, are classified into mutual local-derivability (MLD) classes. Besides the familiar class, there exist an infinite number of new MLD classes, and different MLD classes are distinguished by the inflation rules of their representati…
Measurements of grain growth in nanocrystalline Fe reveal a linear dependence of the grain size on annealing time, contradicting studies in coarser-grained materials, which find a parabolic (or power-law) dependence. When the grain size exceeds approximately 150 nm, a smooth transition from linear to nonlinear growth…
We study the boundary conditions at a fluid-solid interface using molecular dynamics simulations covering a broad range of fluid-solid interactions and fluid densities and both simple and chain-molecule fluids. The slip length is shown to be independent of the type of flow, but rather is related to the fluid organizat…
Devonshire theory provides a successful phenomenological description of many cubic perovskite ferroelectrics such as ${\mathrm{BaTiO}}_{3}$ via a sixth-order expansion of the free energy in the polar order parameter. However, the recent discovery of a novel monoclinic ferroelectric phase in the PZT system by Noheda et…
Infrared studies for the HNO3/0.73 M TBP n-octane system are reported. Two extracted species, TBP · HNO3 and TBP · 2HNO3, were identified in the organic phase. The concentration of the individual species was determined by the analysis of the vibrational band at ∼1650 cm−1. The band at 1648 cm−1 was assigned to the mon…
We investigate the pseudo-Casimir force acting between two charged surfaces confining a single polyelectrolyte chain with opposite charge. We expand the exact free energy to the second order in the local electrostatic field as well as the replicated polymer density field around the mean-field (saddle-point) solution.…
The title compound, 1-keto-4-thioketo-3,6-diphenypyrrolo-[3,4- c ]-pyrrole (MTPP) is a mono-thionated derivative of diketopyrrolopyrrole (DPP) that is known as a novel red pigment on the market. Dithioketopyrrolopyrrole (DTPP) has also attracted attention as a material useful for laser printers as well as optical disk…
Thin layers of a -Si 3 N 4 were synthesized by the pyrolysis of thin films of poly(methylsilane) (PMS) and poly(dimethylsilane) (PDMS) spin-coated on silicon single-crystal wafers and via deposition of the volatile species resulting from the thermal cracking of the bulk precursor in the presence of ammonia. The proces…
The trans-aconitate methyltransferase from the bacterium Escherichia coli catalyzes the monomethyl esterification of trans-aconitate and related compounds. Using two-dimensional (1)H/(13)C nuclear magnetic resonance spectroscopy, we show that the methylation is specific to one of the three carboxyl groups and further…
Several arylthiophene derivatives were synthesized using the Kumada cross-coupling reaction and electropolymerized at a platinum electrode with the aim of investigating the effect of the number of thiophene unit and substitution pattern of the monomers on the spectroscopic and charge storage properties of the resultin…
A new type of optically transparent electrode is reported on--an electrically conductive diamond thin film. The electrode was free-standing (0.38 mm thick and 8 mm in diameter), mechanically polished to a 7-nm rms roughness over a 10-microm linear distance, boron-doped (0.05% B/C in the reactant gas mixture), and moun…
A new hybrid molecular-based ferromagnet of formula [(dmaph)PPh 3 ][MnCr(ox) 3 ], where [(dmaph)PPh 3 ] + stands for the (4-dimethylaminophenyl)triphenylphosphonium cation (ox 2 - being the oxalate anion), has been synthesized. It crystallizes in the monoclinic P 2 1 space group, with lattice parameters a = 13.954(2)…
Crystallization temperature ( T c )-dependent crystal orientations within nanoconfined lamellae have been studied in a self-assembled poly(ethylene oxide)- block -polystyrene (PEO- b -PS) diblock copolymer. The copolymer possesses number-average molecular weights of M̄ n PEO = 8.7K and M̄ n PS = 9.2K, and it forms a m…
Ammonium citratoperoxotitanate(IV), (NH 4 ) 8 [Ti 4 (C 6 H 4 O 7 ) 4 (O 2 ) 4 ]·8H 2 O, was isolated in the solid form. Its crystal structure was solved and refined using single-crystal X-ray data. The compound crystallizes in a monoclinic cell with a = 10.237(2) Å, b = 17.537(4) Å, c = 14.713(3) Å, β = 100.35(1)° ( Z…
Lipid particle size effects on water vapor permeability (WVP) and mechanical properties of whey protein isolate (WPI)/beeswax (BW) emulsion films were investigated. Emulsion films containing 20 and 60% BW (dry basis) and mean lipid particle sizes ranging from 0.5 to 2.0 microm were prepared. BW particle size effects o…
The effect of multiple and delayed jet impact and penetration on the borehole diameter in concrete targets is discussed in this paper. A first-order principle of shaped-charge jet penetration is that target hole volume is proportional to the energy deposited in the target by the jet. This principle is the basis for th…
We show how methods based on an encounter model for diffusion can be used to simulate the grain-boundary diffusion coefficients in ceramics. Boundaries in NiO and ${\mathrm{Al}}_{2}{\mathrm{O}}_{3}$ are used as examples of the method. The anisotropy of diffusion in boundaries (expected from the picture of a grain boun…
Ferroelectric ordering in a nematic liquid crystal system is described using a generalized mean-field potential including effective potentials for both axial and polar interactions. From a self-consistent numerical analysis, a complete phase diagram is obtained as a function of the axial and polar interaction potentia…