Materials Literature
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Semiconductor nanocrystals or quantum dots show a wide range of physical properties depending on their size or shape. In this paper, we show that symmetry is also an important characteristic that can lead to different electronic and optical properties. We use pseudopotential density-functional theory, within a real sp…
Using grazing incidence X-ray diffraction (GIXRD) the three-dimensional surface and interface structure of the {104} calcite surface was investigated under dry and humid atmospheric conditions. The measurement of specular and non-specular crystal truncation rods (CTR) provided information about the periodic order of t…
The chemical compositions of micas from sixwell-characterised sequences have been jointly evaluated in order to analysethe behaviour of illitic substitution (SiAl 1 ! K 1) in relation to diagenetic/metamorphic grade. Data from ~265 crystals,corresponding to 48 samples, were obtained through EDX analyses in SEM and TEM…
A set of spins interact with each other by an arbitrary anisotropic interaction and with external magnetic field. The field varies linearly with time and thus induces spin flips. If initially all spins are oriented in the same direction, then the probability of demagnetization is given exactly by a simple analytical e…
A monoclinic analogue of the mineral hydroxylapatite was found in altered leucogabbro making up one of the intrusive units in the Mesoproterozoic Seagull pluton in northwestern Ontario, Canada. The mineral is part of a replacement assemblage developed metasomatically after igneous plagioclase. It occurs as masses of c…
We report on the permanent magnetism exhibited by 1 nm sized thiol-capped palladium nanoparticles, up to temperatures above 300 K. The hysteresis loop does not change appreciably between 5 and 300 K. The local magnetic anisotropy constant was found to be stronger than 2 meV per Pd atom. The localized character of elec…
The redox behavior of the six-coordinate (por)Mn(NO)(1-MeIm) (por = tetraphenylporphyrin dianion (TPP), tetratolylporphyrin dianion (TTP), or tetra-p-methoxyphenylporphyrin dianion (T(p-OMe)PP)) complexes were examined by cyclic voltammetry at room temperature and at -78 degrees C in two nonaqueous solvents (CH2Cl2 an…
A positive-type photosensitive polybenzoxazole (PSPBO) based on partially tert -butoxycarbonyl ( t Boc) protected poly(semi-alicyclic o -hydroxy amide) (PAtBA) and a photoacid generator, (5-propylsulfonyloxyimino-5 H -thiophene-2-ylidene)−(2-methylphenyl)acetonitrile (PTMA), has been developed for a promising material…
The reaction kinetics of the reversible liquid-phase esterification of acetic acid with 1-butanol was investigated at temperatures between 353.15 and 393.15 K using sulfuric acid as catalyst. The main goal of the work was to study the influence of the initial composition on the reaction rate constants of that industri…
New 2,4-diamino-6-phenyl-1,3,5-triazines carrying one or two semiperfluorinated chains at the phenyl substituent have been synthesized. The thermotropic liquid crystalline properties of the compounds were investigated by polarizing microscopy, differential scanning calorimetry, and X-ray diffraction. The single-chain…
As a new member of the glucose-phosphorylating enzymes, the ATP-dependent hexokinase from the hyperthermophilic crenarchaeon Sulfolobus tokodaii was purified, identified, and characterized. Our results revealed that the enzyme differs from other known enzymes in primary structure and its broad substrate specificity fo…
We present electrical resistivity $(\ensuremath{\rho})$ measurements for the intercalation compound ${\mathrm{Fe}}_{x}{\mathrm{TiSe}}_{2}$ $(0\ensuremath{\leqslant}x<0.16)$ over the temperature range from 4.2 to $300\phantom{\rule{0.3em}{0ex}}\mathrm{K}$, and angle-resolved photoemission spectra for $x=0$, 0.05, an…
Shape-persistent macrocycles with a rigid pyridyl core and a flexible oligo-alkyl corona aggregate to some extent in nonpolar solvents to form large (tubular) aggregates. To increase the assembling tendency, the intraannular pyridyl groups of the macrocycles were alkylated. Unexpectedly, the quarternized macrocycles s…
Diamond nanocrystals (size ~100 nm) emit bright luminescence at 600-800 nm when exposed to green and yellow photons. The photoluminescence, arising from excitation of the nitrogen-vacancy defect centers created by proton-beam irradiation and thermal annealing, closely resembles the extended red emission (ERE) bands ob…
The first material to be predicted from first-principles calculations as half-metallic was NiMnSb, and the research on this material has been intense due to its possible applications in spintronics devices. The failure of many experiments to measure spin polarization to more than a fraction of the predicted 100% has p…
The spatial distribution of the linear dichroic signal associated with aligned beta-sheets in a microtomed section of a Bombyx mori cocoon silk fiber was derived from scanning transmission X-ray microscopy (STXM). The intense C 1s --> pi(amide) peak at 288.25 eV was found to have negligible dichroic signal in transver…
Abstract Summary: In this study, a method for producing super‐amphiphobic surfaces through plasma modification of benzoxazine films is presented. Microroughening and fluorination of the benzoxazine films occurs during the plasma treatment process and a rugged surface with a micro/nano binary structure is formed. The c…
A correlation between the monomeric volume and the dynamic quantity E*(V)/H*, used to provide a quantitative measure of the role of temperature and density on the dynamics, is demonstrated for a series of polymers and glass-forming liquids. We show that monomeric volume and local packing play a key role in controlling…
Our ab initio all-electron Dirac-Fock and the corresponding nonrelativistic limit calculations performed at four Pa-Cl bond distances yield for octahedral PaCl(6) (2-) the optimized Pa-Cl bond distances of 2.758 and 2.771 Angstroms, respectively. Dirac scattered wave and its nonrelativistic limit calculations are perf…
We investigate the ability of an applied electric field to convert the morphology of a diblock-copolymer thin film from a monolayer of spherical domains embedded in the matrix to cylindrical domains that penetrate through the matrix. As expected, the applied field increases the relative stability of cylindrical domain…