Materials Literature
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The structure was solved at 2.5 A resolution using multiwavelength anomalous dispersion (MAD) scattering by Se-Met residues. The subunit of N(10)-formyltetrahydrofolate synthetase is composed of three domains organized around three mixed beta-sheets. There are two cavities between adjacent domains. One of them was ide…
In this article we report the determination of residual stresses in diamond films grown on Si (100) by using a plate bending theory and a bimetal theory combined with micro-Raman spectroscopy. Raman spectra show that with increase in the film thickness the characteristic diamond line shifts from higher wave numbers (&…
When a pentagon defect is introduced into a graphite sheet, a cone structure is formed. We simulate scanning-tunneling-microscopy (STM) images of the graphitic cone based on density-functional calculations. Simulated STM images show approximately $\sqrt{3}\ifmmode\times\else\texttimes\fi{}\sqrt{3}$ superstructures con…
We apply first-principles calculations to study structural and electronic properties of a semiconductor carbon nanotube bent to a large angle. The geometry optimization results in fourfold carbon rings at the bend region. These fourfold rings, seldomly seen in carbon structures, result from the collapse of carbon hexa…
In iron tridecazinc, the FeZn13 unit cell contains two Zn12 icosahedra which are Fe-centred and two Zn2 dumb-bells coordinated by eight icosahedra. Zn12 icosahedra form chains along the c axis by vertex-sharing, and are further interlinked through octahedra-sharing and vertex-to-vertex bonds.
An x-ray-diffraction method that directly senses the phase of the structure factor is demonstrated and used for determining the local polarity of thin ferroelectric films. This method is based on the excitation of an x-ray standing-wave field inside the film as a result of the interference between the strong incident…
Commercially available fourth and fifth generation poly(propyleneimine) (PPI) dendrimers were functionalized with acetyl chloride and deuterated acetyl chloride. Their solution properties in water and D2O were measured with dilution viscometry, densitometry, rheology, and small-angle neutron scattering (SANS) and comp…
The conditions for protein film preparation from an alkaline dispersion of a pea protein isolate were investigated in the presence of polyols as plasticizers. Mechanical and barrier properties of resulting films were studied as a function of protein dispersion conditions, protein and plasticizer concentrations and rat…
Neutron Rietveld analyses have been carried out on Y 2 Ru 2 O 7 and Nd 2 Ru 2 O 7 to clarify the primary mechanism of the transition at T G to the spin-glass-like state which is accompanied by the specific heat jump. The results indicate that the lattice system does not seem to participate in the transition and change…
Metal-free amorphous hydrocarbon (a-C:H) and Ti-containing hydrocarbon (Ti–C:H) coatings have been synthesized in a hybrid chemical vapor deposition (CVD)/physical vapor deposition (PVD) system which combines inductively coupled plasma (ICP) and sputter deposition. a-C:H coatings have been fabricated by ICP assisted C…
The electronic structure and chemical bonding mechanism of the Heusler alloy Cu 2 MnAl are studied on the basis of band-structure calculations, using the full-potential linearized augmented-plane-wave (FLAPW) method. The calculations are performed within both the local spin-density approximation (LSDA) and the general…
We have examined the decay of thermalized excitons in cuprous oxide $({\mathrm{Cu}}_{2}\mathrm{O})$ and determined their lifetime against two-body decay (i.e., Auger recombination). The experiments are conducted at $T=70 \mathrm{K}$ with near-resonant picosecond excitation to ensure a thermal equilibrium between ortho…
In this article, a mathematical model is proposed for predicting solvent self-diffusion coefficients in amorphous glassy polymers based on free volume theory. The basis of this new model involves consideration of the plasticization effects induced by small molecular solvents to correctly estimate the hole-free volume…
The formation of nanosized Si crystals in dual-frequency plasma-enhanced chemical-vapor-deposited silicon oxides is identified in this study. As a higher SiH4N2O gas flow rate ratio is employed during the deposition process, the silicon-to-oxygen atomic ratio and the dangling bond density both increase. The resulting…
There are three members of the HtrA family of serine proteases, YkdA, YvtA, and YyxA, encoded in the chromosome of Bacillus subtilis. In this study, we report on the promoter structure and regulation of ykdA expression. The ykdA gene is heat inducible, exhibiting a biphasic pattern of expression during a 60-min interv…
A computer simulation method is devised whereby the change in location of a triple point is followed as one of the parameters of the interaction potential is modified. The method, a two-dimensional Clapeyron integration, is illustrated here for the case of a hard-core plus repulsive Yukawa potential of variable range.…
Electrical conductivity effects in biaxially stretched polyethylene terephthalate (PET) films of 6 μm thickness and 68% degree of crystallinity were investigated by means of dielectric relaxation spectroscopy in the frequency range 10−2–106 Hz and at temperatures higher than the glass transition temperature (∼85 °C) u…
A set of new aromatic polyamides were synthesized by the direct phosphorylation condensation of 4-(1-adamantyl)-1,3-bis-(4-aminophenoxy)benzene with various diacids. The polymers were produced with high yields and moderate to high inherent viscosities (0.43–1.03 dL/g), and the weight-average molecular weights and numb…
An analysis of the second-order resonant Raman spectra of single-walled carbon nanotubes using different laser energies in the range 1.58--2.71 eV is presented. Major emphasis is given to the overtones and combination modes associated with the two dominant features of the first-order spectra, the radial breathing mode…
Optical properties of Nd 3+ -doped phosphate glasses have been studied on the basis of the Judd-Ofelt theory. With the intermediate cross-section value and the weak 4 / 6 parameter, we expect a relatively prominent 4 F 3/2 4 I 11/2 laser emission. The quenching effect of the emission intensity is discussed in terms of…