Materials Literature
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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…
The magnetic, transport, and structural investigations of the ${\mathrm{CaMn}}_{1\ensuremath{-}x}{\mathrm{Mo}}_{x}{\mathrm{O}}_{3}$ manganites show that orbital and charge ordering are induced by Mn-site doping in pure calcium based manganites. Starting from a cluster glass behavior at x\ensuremath{\approx}0.04, orbit…
Polycrystalline samples of SnBi 4 Te 7 and PbBi 4 Te 7 with deviations from stoichiometry in different sublattices were synthesized by melting and quenching followed by prolonged annealing and hot-pressing. At room temperature SnBi 4 Te 7 exhibits both n-type conductivity (Te deficiency and Sn or Bi excess) and p-type…
A new synthesis of chlorins has been developed, based upon the acid-catalyzed condensation of dialdehydes AB with dipyrromethanes CD.
A room-temperature synthesis route for thin films of amorphous silica ( a -SiO 2 ) based on irradiation of a silicon-containing polymer by UV light in pure O 2 atmosphere has been developed. The chemical conversion of spin-coated films of poly(pentamethyldisilylstyrene) (pPMDSS) to silicon oxycarbide and finally to am…
The melt condensation polymerization of the AB 2 monomer dimethyl 5-(2-hydroxyethoxy)isophthalate exhibits unusual molecular weight growth characteristics. The number-average molecular weight ( M n ) reaches a plateau value after a relatively short polymerization time, whereas the weight-average molecular weight ( M w…
Colossal magnetoresistance manganites in a wide composition range can be systematically characterized by Raman spectrometry with respect to the cation substitution in the A sublattice of the perovskite structure, oxygen isotope exchange, and variations of the ${\mathrm{Mn}}^{3+}{/\mathrm{M}\mathrm{n}}^{4+}$ ratio. The…
Semiinterpenetrating polymer networks (semi-IPNs) were synthesized from castor oil-based polyurethane (PU) and 20 wt % nitrokonjac glucomannan (NKGM) with weight-average molecular weights ( M w ) from 2.86 × 10 4 to 14.1 × 10 4 . Results from the dynamic mechanical analysis, differential scanning calorimetry, wide-ang…
The calcination kinetics of ammonium pentaborate was investigated by thermogravimetry (TG) using the Coats−Redfern and genetic algorithm methods. Various methods for determining the reaction parameters using thermal analysis data were improved. Genetic algorithms can be considered as a new method for the determination…
${}^{151}\mathrm{Eu}$ (and ${}^{57}\mathrm{Fe})$ high-pressure M\"ossbauer investigations on ${\mathrm{EuFe}}_{2}{\mathrm{P}}_{2}$ reveal that the pressure-induced isostructural phase transition $3\ensuremath{\lesssim}p\ensuremath{\lesssim}9$ GPa is accompanied by a continuous valence transition from ${\mathrm{Eu}}^{2…
Glucose-triacylglycerol (TAG) mixed substrates were used to modulate the physical and mechanical properties of medium-chain-length poly(hydroxyalkanoates) (mcl-PHAs). Pseudomonas resinovorans NRRL B-2649 grew and produced mcl-PHAs on glucose and TAGs (coconut oil, C; soybean oil, S) after 24 h in a shake flask culture…
The organic gelator 1,3:2,4-dibenzylidene sorbitol (DBS) self-organizes to form a 3-D network stabilized by hydrogen bonds at relatively low concentrations in a variety of nonpolar organic solvents and polymers. The resultant network consists of nanofibrils and is responsible for the physical gelation of the matrix co…
We find the exact ground state energy and magnetic moment for an arbitrary magnetic field H of the classical Heisenberg model of spins on the vertices of an icosidodecahedron. This model provides an accurate description of the magnetic properties of the giant paramagnetic molecule ${{\mathrm{Mo}}_{72}{\mathrm{Fe}}_{30…
The luminescence sensitivity of natural quartz is significantly enhanced if heated beyond the first and second crystal phase transitions, in the temperature range 500-1100 °C. This work employs a number of complementary spectroscopic methods to obtain a fuller understanding of the mechanisms of this sensitization proc…
Summary The pulp and paper industry in China has been growing rapidly as the nation's population and economy have grown. As a result, there has been a huge demand for pulp and paper raw materials. China has a long tradition for using non-wood raw materials for pulp and paper due to its limited forest resources and ric…