Materials Literature
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Cycloheptanol, cyclo-octanol, cyanoadamantane and cis-1,2-dimethylcyclohexane are known to form plastic crystals which can be supercooled to show a glass transition at a temperature Tg. The molecular dynamics in different plastic phases is studied in their supercooled states using dielectric spectroscopy (frequency ra…
Boehmite and pseudoboehmite were studied in order to find the effect of their individual properties upon the properties of transitional alumina and α-Al 2 O 3 produced thereof; the influence of steaming on these properties was also considered. Samples were characterized by X-ray powder diffraction, crystalline structu…
NAD+-dependent formate dehydrogenase (FDH) from Candida boidinii was cloned and expressed to a high level in Escherichia coli (20% of soluble E. coli protein). Molecular modelling studies were used to create a three-dimensional model of C. boidinii FDH, based on a known structure of the Pseudomonas sp. 101 enzyme. Thi…
The substitution of rare-earth ions into insulating host crystals introduces lattice strains and, for non-trivalent sites, a need for charge compensation. Such effects alter the site symmetry and this is reflected in properties such as the wavelength, linewidth, lifetime and relative intensity of the rare-earth transi…
We present a theoretical methodology to study the electronic response properties of a chromophore physisorbed on a metal particle. In particular the chromophore is treated at ab initio level whereas the metal particle is described through its dielectric properties. The use of a boundary elements method for the resolut…
New high surface area carbon materials were prepared at low temperature (600 °C) using zeolite (Y, Beta, and ZSM-5) and montmorillonite clay (K10) templates. Acrylonitrile, furfuryl alcohol, pyrene, and vinyl acetate precursors were polymerized and carbonized in each of the inorganic matrixes without the addition of a…
Dioxygen accelerates back electron transfer (BET) processes between a fullerene radical anion (C60) and a radical cation of zinc porphyrin (ZnP) in photolytically generated ZnP.+-C60.- and ZnP.+-H2P-C60.- radical ion pairs. The rate constant of BET increases linearly with increasing oxygen concentration without, howev…
Figure 1 shows a representative set of ISF’s, made at \nwave vectors below, near, and above the position qm of \nthe main peak in S(q). Increasing the concentration \nfrom freezing (ø /—0.494) to φ "0.574 lengthens the \noverall decay time of f ( q y r ) by nearly four decades, from \nabout 10s to 109 /is, and signifi…
The fundamental question of how chirality affects the electronic coupling of a nanotube to metal contacts is important for the application of nanotubes as nanowires. We show that metallic-zigzag nanotubes are superior to armchair nanotubes as nanowires, by modeling the metal-nanotube interface. More specifically, we s…
Grand canonical Monte Carlo simulations have been performed to determine the adsorption behavior of Ar and Kr atoms on the exterior surface of a rope (bundle) consisting of many carbon nanotubes. The computed adsorption isotherms reveal phase transitions associated with the successive creation of quasi-one-dimensional…
In this work the long-wave limit of electron-electron interaction arising from the exchange of virtual phonons in an approximation close to "jelly" model is considered. It is shown that the interaction through the exchange of virtual phonons is actually not screened in contrast to the Coulomb one; this just leads to i…
Materials science has emerged as one of the central pillars of the modern physical sciences and engineering, and is now even beginning to claim a role in the biological sciences. A central tenet in the analysis of materials is the structure-property paradigm, which proposes a direct connection between the geometric st…
The salient feature defining a supercooled liquid is the extraordinary increase o f its characteristic structural (a) relaxation times as the liquid is cooled below its melting point T m. For instance, the coefficient of shear viscosity (η) increases sm oothly by as much as 15 orders of m agnitude over a temperature (…
Cube-textured silver buffer layers have been fabricated using the easily scalable technique of electro-epitaxial deposition. Continuous 150 nm thick silver films with in-plane FWHM values of 8° have been epitaxially deposited directly onto cube-textured Ni, Ni-10 wt% Cr and NiFe substrates using no intermediate buffer…
The present contribution deals with one of the possible structure types of nongraphitic carbon adsorbents. The proposed structure consists of infinite strips of condensed aromatic rings arranged into a hexagonal honeycomb-like structure with the edge formed only by sp2 carbon atoms. Quantum chemical calculations were…
The ligational behavior of meso-arylsapphyrins and rubyrins toward Rh(I) is investigated. Sapphyrins form monometallic complexes with coordination of one imine and amine type nitrogens of the bipyrrole unit in an eta2 fashion. The Rh(I) coordination is completed by the presence of two ancillary carbon monoxide ligands…
Mononuclear, dinuclear, and polymeric Ru(II) complexes formed from terthienylalkylphosphino redox-switchable hemilabile ligands demonstrate that this class of ligand provides electrochemical control over the electronic properties, coordination environments, and reactivities of bound transition metals. Specifically, [C…
The synthesis of high molecular weight star-shaped polymers comprising poly(1,3-cyclohexadiene) arms coupled to a divinylbenzene (DVB) core is reported. In-situ FTIR spectroscopy was used to verify first-order polymerization kinetics for 1,3-cyclohexadiene at 40 °C in cyclohexane with a 10 wt % monomer concentration u…
We report an experimental study of colloidal inclusions in free-standing films of smectic-C* liquid crystal. The inclusions are cholesteric droplets that form above the bulk smectic-C*-7cholesteric transition temperature. Each droplet confined in a two-dimensional (2D) system, is accompanied by a topological defect. T…
The carburization of ethylene pyrolysis tubes is characterized using hardness, x-ray diffraction (XRD), scanning electron microscopy (SEM) and optical microscopy. The through-wall changes in magnetic properties due to carburization are quantified using vibrating sample magnetometer (VSM) measurements. The thickness an…