Materials Literature
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The strong Eu3+ photoluminescence in xSnO2–(100–ܨ)SiO2 derived bythe sol–gel method was reported. It was shown that Eu3+ ions were embedded in SnO2 nanocrystals (tetragonal, rutile) surrounded by a SiO2 glass matrix. Time-resolved photoluminescence spectra and excitation spectra revealed that Eu3+ ions could receive e…
The effect of carbon isotope substitution on ${T}_{C}$ in the intermetallic perovskite superconductor $\mathrm{Mg}\mathrm{C}{\mathrm{Ni}}_{3}$ is reported. Four independent groups of samples were synthesized and characterized. The average ${T}_{C}$ for the $^{12}\mathrm{C}$ samples was found to be $7.12\ifmmode\pm\els…
The high-temperature phases of the alkali-metal oxalates M2[C2O4] (M = K, Rb, Cs), and their decomposition products M2[CO3] (M = K, Rb, Cs), were investigated by fast, angle-dispersive X-ray powder diffraction with an image-plate detector, and also by simultaneous differential thermal analysis (DTA)/thermogravimetric…
Abstract The mechanical, morphological behavior and water absorption characteristics of polypropylene (PP) and silica, or PP and rice‐husk, composites have been studied. The silica used in this study as filler was a commercial type produced from soluble glass or rice husks. The compatibilizing effect of PP grafted wit…
The crystallization of nylon-6 clay nanocomposite was studied by variable temperature wide-angle X-ray scattering (WAXS) and Fourier transform infrared spectroscopy (FTIR). Nylon-6 was found to crystallize into γ phase at 210 °C, as indicated by its characteristic peaks in WAXS. However, an additional peak was observe…
The formation of Ag nanoparticles by electrochemical techniques has been investigated through a time-resolved UV-vis spectroscopy study. The formation of Ag(4)(2+) clusters is suggested as the main precursors to the particle formation. The mechanism also considers the electrodeposition which occurs as a parallel proce…
The effect of the volume expansion on the total linear magnetostriction of Fe85Ga15, Fe80Ga20, and Fe71Ga29 mold-cast bulk alloys was investigated by measuring the change in length with applied field longitudinal and perpendicular to the temperature gradient during solidification. In the magnetically saturated state,…
The influence of postannealing in different gaseous environments on the optical properties of indiu-tin-oxide (ITO) thin films deposited on glass substrates using e-beam evaporation has been systematically investigated. It is found that the annealing conditions affect the optical and electrical properties of the films…
A water-soluble conjugated polymer was developed that displays significant fluorescence quenching (25% quenching of polymer's fluorescence at quencher concentrations of 500 nM) and forms well-defined multilayer structures via electrostatic deposition. The polymer contains alternating 2,5-thienyl- and 2,5-bis[2-( N,N -…
Time-dependent density functional theory (TD-DFT) is applied to the CD spectra of Lambda(deltadeltadelta)-(+)-[Co(S-pn)n(en)(3-n)]3+ (n = 1, 2, 3) and Lambda(deltadeltadelta)-(+)-[Co(en)3]3+ as well as the stereoisomers Delta-((delta)n(lambda)(3-n))-(-)-[Co(S-pn)n(en)(3-n)]3+ (n = 1, 2, 3) and Delta(deltadeltadelta)-(…
Incorporation of carbon nanotubes into epoxy resin composites has the effect of increasing electrical conductivity at low percolation levels. An amphiphilic molecule such as palmitic acid has been used to increase the surface contact area and to improve the dispersion of the carbon nanotube bundles in the prepolymer.…
A series of hybrid inorganic-organic copper(II) hydroxy n-alkylsulfonate with a triangular lattice, Cu(2)(OH)(3)(C(n)H(2)(n)(+1)SO(3)) (n = 6, 8, 10), are prepared by anion exchange, starting from copper hydroxy nitrate Cu(2)(OH)(3)NO(3). These compounds show a layered structure as determined by X-ray diffraction, wit…
We couple morphological studies of binary, immiscible blends with mechanical studies of deformation and fracture to determine the influence of the blend composition on the initiation and propagation of cracks in polymeric materials. The Cahn−Hilliard (CH) method is employed to simulate the structural evolution of the…
Abstract Thermally‐induced spin variation behavior of [Fe II (BPMEN)(CH 3 CN) 2 ](ClO 4 ) 2 in CD 3 CN solution [low spin (LS)−high spin (HS)] was investigated. Variable temperature solution magnetic susceptibility measurements gave Δ H ° LS−HS = 39.7 ± 2.0 kJ·mol −1 and Δ S ° LS−HS = 135 ± 9 J·mol −1 K −1 values. The…
An expanded porphyrin with six pyrrole units, a meso-aryl hexaphyrin, acts as a dienophile in Diels–Alder reactions with o-xylylene. Consecutive double cycloadditions of the hexaphyrin with a bis-o-xylylene equivalent leads to an anthracene-bridged hexaphyrin dimer (see scheme), whose unique Z-shaped structure has bee…
A high-resolution inelastic neutron scattering (INS) study of fully deuterated ${\mathrm{Mn}}_{12}$ acetate provides accurate spin-Hamiltonian parameters for this prototype single-molecule magnet. The ${\mathrm{Mn}}_{12}$ clusters deviate from axial symmetry, a nonzero rhombic term in the model Hamiltonian leading to…
The specific heat capacities C p of blends consisting of cis -polyisoprene (PI) and poly(vinylethylene) (PVE) were measured in the temperature range from 80 to 320 K by using an adiabatic calorimeter. The configurational heat capacities C conf of blends around the glass transition temperature T g have been determined…
The temperature and the Gibbs free energy of activation of the α-relaxation in ethylene-1-octene and ethylene-1-hexene copolymers drop with decreasing crystal size which is triggered by increasing concentration of short-chain branches and/or increasing cooling rate during melt crystallization, respectively. The activa…
Isolated slightly hydrophilic chains of poly(isocyanodipeptides) (PICs) adsorbed on mica were studied by intermittent contact mode−scanning force microscopy (IC−SFM) in an ambient atmosphere controlled both with respect to the relative humidity (RH) and the presence of CHCl 3 vapor. SFM revealed that the average chain…
A broad range of measurements of ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}\mathrm{Cr}{\mathrm{O}}_{3}\phantom{\rule{0.2em}{0ex}}(0\ensuremath{\leqslant}x\ensuremath{\leqslant}0.5)$ are presented. $\mathrm{La}\mathrm{Cr}{\mathrm{O}}_{3}$ is an insulating antiferromagnet with N\'eel temperature ${T}_{N}=293\pha…