Materials Literature
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We demonstrate a three-dimensionally macroporous Si 9R polytype that exhibits a different electronic structure than bulk diamond-structured Si. Unlike the latter one which has an indirect-bandgap transition close to the zone boundary, the conduction band minimum in this material, as revealed by valence electron energy…
Abstract Biominerals provide excellent mechanical properties for skeletal support and protection, rivaling and even outperforming those of many engineered ceramics fabricated at high temperatures and pressures. However, the mechanisms of biomineralization are still poorly understood. To make progress in this direction…
We report a simple and manageable growth method for placing dense three-dimensional Ge quantum dot (QD) arrays in a uniform or a graded size distribution, based on thermally oxidizing stacked poly-SiGe in a layer-cake technique. The QD size and spatial density in each stack can be modulated by conditions of the Ge con…
Abstract The radiochemical degradation of bisphenol A polysulfone was investigated under a γ‐ray dose rate of 24 kGy h −1 up to 30.7 MGy total absorbed dose at 60 °C using gel permeation chromatography, sol–gel analysis, glass transition and rheometry measurements, and oxidation profile measurements by microscopy coup…
The resistance of piles when fingers move on artificial furs is important for tactile comfort. To evaluate the resistance of piles, a simple device for measuring the horizontal force F H of artificial furs was developed and attached to a KES-SE surface tester. The horizontal force (F H ) generated when a bar moves on…
Disperse dyes are very hydrophobic molecules which are usually milled in the presence of large amounts of dispersing agents (synthetic surfactants) in their commercial form. In this study the synthetic surfactants are substituted by phosphatidylcholine liposomes in the dye preparation, in order to use natural and biol…
It is shown that longitudinal and transverse concentration dynamic structure factors of a metallic binary glass ${\text{Mg}}_{70}{\text{Zn}}_{30}$ obtained by molecular dynamics (MD) simulations contain pronounced low-frequency peaks, that correspond to boson-peak modes. With a purpose of theoretical analysis of MD-de…
Abstract Low‐ k dielectric films were deposited by PECVD from mixtures of hexamethyldisiloxane (HMDSO), ethylene, and oxygen. After deposition the films were thermally annealed in order to reduce their permittivity. Different deposition conditions were investigated in order to accomplish the best trade‐off between low…
Four kinds of solid acid catalysts have been prepared and their catalytic esterification activity compared using a model reaction, namely the synthesis of tributyl citrate (TBC). The results indicate that the solid acids show good catalytic performance and are reusable. Under optimum conditions and using M- as a catal…
Abstract When NiTi powder compacts containing Nb wires are heated above 1 170 °C, each Nb wire reacts with adjacent NiTi powders to form a eutectic liquid which wicks into the space between the remaining NiTi powders. This creates a macropore at the location of the Nb wire while eliminating the microporosity between N…
Abstract Caddisfly (Trichopera) can glue diverse material underwater with a silk fiber. This makes it a particularly interesting subject for biomimetcs. Better understanding of silk composition and structure could lead to an adhesive capable to close bleeding wounds or to new biomaterials. However, while spiderweb or…
The influence of untreated and treated OPEFB content on the mechanical properties of acrylic impact-modified PVC was investigated. The formulations were first dry blended before being milled into sheets on a two-roll mill. Test specimens were then hot pressed. The modulus significantly increased while the impact and f…
Temperature and field dependent magnetic Compton profiles of BixCo2−xMnO4 (x=0 and 0.3) multiferroics are reported. The magnetic Compton profiles and total spin moments are interpreted in terms of Mn/Co-3d contribution. Mn spin moments are found to be dominating in total magnetization whereas a small contribution of C…
We report inelastic neutron scattering study of a quasi-two-dimensional $S=\frac{1}{2}$ dimer system piperazinium hexachlorodicuprate under hydrostatic pressure. The spin gap $\ensuremath{\Delta}$ becomes softened with the increase of the hydrostatic pressure up to $P=9.0\text{ }\text{kbar}$. The observed threefold de…
The thermal stability of the prominent 3577 cm−1 infrared absorption band in ZnO, assigned to an O–H stretch mode adjacent to a Li atom on Zn site (LiZn), is studied. Employing slow sample cooling after annealing, the 3577 cm−1 peak remains at temperatures ≤1250 °C, consistent with previous reports. However, if the sa…
Understanding the mechanism for growing TiO(2) nanotubes is important for controlling the nanostructures. The hydroxide nano-islands on the Ti surface play a significant role at the initial stage of anodization by forming the very first nano-pores at the interface between hydroxide islands and substrate and eliminatin…
The domain structures of relaxor-ferroelectric $\text{Pb}({\text{Zn}}_{1/3}{\text{Nb}}_{2/3}){\text{O}}_{3}\text{\ensuremath{-}}9\mathrm{%}{\text{PbTiO}}_{3}$ (PZN-9PT) single crystals with a morphotropic phase boundary (MPB) composition are observed with a scanning second harmonic generation (SHG) microscope. Three-d…
We investigate quantum pumping of massless Dirac fermions in an ideal (impurity free) double layer of graphene. The pumped current is generated by adiabatic variation in two gate voltages in the contact regions to a weakly doped double graphene sheet. At the Dirac point and for a wide bilayer with width $W⪢\text{lengt…
The relations between the thermal conductivity of cagelike structures and their crystal parameters are investigated using a two-dimensional toy model. The model consists of host atoms on a rectangular lattice with fillers at the center of each rectangle. The effect of mass and size of the filler on thermal conductivit…
The difficulties involved in trying to use hospital or clinical radiographic installations, equipment, and personnel for forensic investigation have already been mentioned in Chapter 33. Attempts to use mobile x-ray equipment temporarily “borrowed” from the clinical facility will meet with similar problems of accessib…