Materials Literature
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NiL4X2·xH2O compounds [L=1-(2-carbamoylethyl)-4-methylimidazole (C4MIm), 1-(2-carbamoylethyl)benzimidazole (CBIm) or 1-(2-carbamoylethyl)-5,6-dimethylbenzimidazole (CMMBIm)] have been prepared and characterised and the effect of different axial ligands, X, on the magnetic properties of the complexes has been examined.…
The biostability of a series of polypyrrole (PPy)-coated polyester fabrics was investigated in an in vitro model. PPy-coated sample fabrics were incubated in saline at 37 degrees C for 1 and 2 weeks. After each period of incubation, the surface electrical resistivity of the sample fabrics was measured to monitor the c…
The structural, magnetic, and electrical properties of ${\mathrm{Y}}_{0.5}{\mathrm{Sr}}_{0.5}{\mathrm{MnO}}_{3}$ and ${\mathrm{Y}}_{0.4}{\mathrm{Sr}}_{0.6}{\mathrm{MnO}}_{3}$ have been measured. Magnetic data [e.g., the frequency dependence of ac susceptibility, the zero-field-cooled and field-cooled magnetization beh…
L-Threonine acetaldehyde-lyase (threonine aldolase, TA) is a pyridoxal-5'-phosphate-dependent (PLP) enzyme that catalyzes conversion of L-threonine or L-allo-threonine to glycine and acetaldehyde in a secondary glycine biosynthetic pathway. X-ray structures of Thermatoga maritima TA have been determined as the apo-enz…
Chitosan and chitosan-amino acid derivatives were explored to engineer poly(D,L-lactic acid) (PDL-LA) as an extracellular matrix-like surface to promote cell adhesion and growth. Four kinds of chitosan-amino acid derivatives were prepared to mimic the carbohydrate moieties of cell matrix glycoprotein. The chitosan-ami…
Abstract Silica particles were treated by silane coupling agents to study the effects of surface chemistry of silica particles on the secondary structure formed by silica particles in styrene–butadiene rubber (SBR). The relation between the size of secondary structure and tensile properties of silica‐filled SBR vulcan…
In this paper we study the magnetocaloric effect in the rare-earth cobalt intermetallic compounds $R{\mathrm{Co}}_{2}(R=\mathrm{Dy},\mathrm{Ho},\mathrm{Er}).$ We use a theoretical model, in which the localized spins of the rare-earth ions are immersed into an effective subsystem of the itinerant electrons. In the calc…
Rhenium(IV) sulfide, ReS(2), has been prepared with nanotubular morphology by carbon nanotube templating. A multiwall carbon nanotube material was impregnated with solutions of NH(4)ReO(4) or ReCl(5), followed by drying and sulfidation with H(2)S at 1000 degrees C. The composite material synthesized was characterized…
We investigate the microscopic mechanisms responsible for microdomain alignment in block copolymer solutions exposed to an electric field. Using time-resolved synchrotron small-angle x-ray scattering, we reveal two distinct processes, i.e., grain boundary migration and rotation of entire grains, as the two dominant mi…
The time dependent response of the magnetic and transport properties of Fe-doped phase separated (PS) manganite La(0.5)Ca(0.5)MnO3 is reported. The nontrivial coexistence of ferromagnetic (FM) and non-FM regions induces a slow dynamics which leads to time relaxation and cooling rate dependence within the PS regime. Th…
Using in situ small-angle X-ray scattering, the electric field induced orientation in a block copolymer having a cylindrical microdomain morphology was investigated. Studies were performed with the copolymer in different initial states. Beginning with a disordered copolymer, composition fluctuations are oriented by th…
Many transition metal compounds show saturation of the resistivity at high temperatures, T, while the alkali-doped fullerenes and the high-Tc cuprates are usually considered to show no saturation. We present a model of transition metal compounds, showing saturation, and a model of alkali-doped fullerenes, showing no s…
Scanning tunneling spectroscopy images of Bi$_2$Se$_3$ doped with excess Bi reveal electronic defect states with a striking shape resembling clover leaves. With a simple tight-binding model we show that the geometry of the defect states in Bi$_2$Se$_3$ can be directly related to the position of the originating impurit…
The magnetic order resulting from an indirect exchange between magnetic moments in the metallic phase of a Ga(1-x)Mn(x)As bilayered structure is studied "via" Monte Carlo simulation. The coupling mechanism involves a perturbative calculation in second order of the interaction between the magnetic moments and carriers…
We calculate magnetic anisotropy energy of Fe and Ni by taking into account the effects of strong electronic correlations, spin-orbit coupling, and non-collinearity of intra-atomic magnetization. The LDA+U method is used and its equivalence to dynamical mean-field theory in the static limit is derived. The effects of…
The high-pressure behaviour of alpha-PbF2 has been investigated by angular-dispersive synchrotron X-ray powder diffraction up to 6.55(8) GPa. The fit of a 3rd-order Birch-Murnaghan equation-of-state gave the volume at zero pressure V0=194.14(4)Å$^3 and the bulk modulus b_0=47.0(6)GPa with the pressure derivative b'=7.…
The classic Lifshitz-Slezov-Wagner theory of ripening assumes that within a closed system, the total volume of the phase undergoing ripening remains constant while the total surface area of the phase decreases. We present here the ripening behavior in an open system in which the total surface area of the phase undergo…
Vesicles prepared in water from a series of diblock copolymers “polymersomes” are physically characterized. With increasing molecular weight M̄ n, the hydrophobic core thickness for self-assembled bilayers of poly(ethylene oxide)−polybutadiene increases up to ∼20 nm, which is considerably greater than any previously s…
Very rough surfaces can suspend small water drops, prevent wetting, and cause contact angles to approach 180°. A criterion based on contact line density is proposed for predicting the conditions that produce these ultrahydrophobic surfaces, where, above a critical value, drops are suspended by asperities. Critical val…
Polyesters such as poly(3-hydroxybutyrate) (PHB) or other polyhydroxyalkanoates (PHA) have attracted commercial and academic interest as new biodegradable materials. The ability to degrade PHA is widely distributed among bacteria and fungi and depends on the secretion of specific extracellular PHA depolymerases (e-PHA…