Materials Literature
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The R-factor and R-free are commonly used to measure the quality of protein models obtained in X-ray crystallography. Well-refined protein structures usually have R-factors in the range of 20-25%, whereas intrinsic errors in the experimental data are usually around 5%. We use molecular dynamics simulations to perform…
Multilayered inorganic−organic hybrids were prepared by cohydrolysis and polycondensation of alkyltriethoxysilanes (C n TES, n = 8−18) and tetraethoxysilane (TEOS). Thin films were deposited from homogeneous solutions containing the oligomeric species by dip-coating. Self-assembly of co-condensed oligomers into lamell…
Abstract The direction of the transition dipole moments for the vibrations of the single W O W and double W O O W oxygen bridges in layered scheelite tungstates is derived from the Polarized infrared and Raman spectra of the KGd(WO 4 ) 2 single crystal. Their experimental values are compared with those obtained from t…
The Cd(C 5 F 6 HO 2 ) 2 ·2H 2 O complex was investigated by X-ray crystallography, mass spectroscopy, 1 H NMR spectroscopy, TG−DTG thermal measurements, and infrared transmittance spectroscopy. X-ray single-crystal data show that the cadmium ion is chelated by the oxygens of the hfa anion ligand and bound to the oxyge…
An organic radical, 1,3,5-trithia-2,4,6-triazapentalenyl (TTTA), exhibits a first-order phase transition between a paramagnetic high-temperature (HT) phase and a diamagnetic low-temperature (LT) phase, with a surprisingly wide thermal hysteresis loop over the temperature range 230--305 K. The crystal structure of the…
Binary mixtures of the aggregating helicene 1 with dodecane have, at dodecane concentrations >30 vol %, a nematic liquid crystalline phase and, at dodecane concentrations ≲5 vol %, a hexagonal columnar liquid crystalline phase. The helical structure with donor and acceptor groups at opposite ends gives rise to a molec…
The XPS (ESCA) method was employed to quantitatively determine polyelectrolyte adsorption on the mica basal plane from low ionic strength solutions. Particular emphasis was given to the effect of the polyelectrolyte charge density. By combining the results obtained from XPS and surface force measurements it was possib…
Water and oxygen molecules determine many of the properties of amorphous SiO2 used in several technologies, but the underlying atomic-scale processes remain unresolved. We report results of first-principles calculations showing that a wide range of behavior is possible in an amorphous environment, including diffusion…
Long-range effects on the pyroelectric coefficient of a ferroelectric superlattice consisting of two different ferroelectric materials are investigated based on the Transverse Ising Model. The effects of the interfacial coupling and the thickness of one period on the pyroelectric coefficient of the ferroelectric super…
Abstract Raman spectroscopy was used to determine the molecular behaviour of DMSO and DMSO‐ d 6 , and to compare it with that of DMSO in DMSO‐intercalated kaolinites. For DMSO at 298 K two bands are observed at 2994 and 2913 cm −1 and are assigned to the antisymmetric and symmetric CH stretching modes. At 77 K the deg…
Abstract Tensile tests on poly (methyl methacrylate) (PMMA) were conducted to clarify the effects of humidity and strain rate on tensile properties, particularly Young's modulus. Prior to the tensile tests, specimens were kept under various humidity conditions at 293 K, which were the same as the test conditions, for…
We derive a drift-diffusion equation for spin polarization in semiconductors by consistently taking into account electric-field effects and nondegenerate electron statistics. We identify a high-field diffusive regime which has no analogue in metals. In this regime there are two distinct spin diffusion lengths. Further…
Atomistic studies are carried out to investigate the formation and evolution of defects during nanoindentation of a gold crystal. The results in this theoretical study complement the experimental investigations [J. D. Kiely and J. E. Houston, Phys. Rev. B, v57, 12588 (1998)] extremely well. The defects are produced by…
The ferromagnetic resonance spectrum of a normally magnetized YIG disk, with thickness of 4.75$μ$m and radius of 80$μ$m, is measured at room temperature both by magnetic resonance force microscopy and by standard detection of the microwave susceptibility. The comparison indicates that MRFM represents one of the most p…
Many crystalline materials show chemical short range order and relaxation of neighboring atoms. Local structural information can be obtained by analyzing the atomic pair distribution function (PDF) obtained from powder diffraction data. In this paper, we present the successful extraction of chemical short range order…
It has been shown that under joint action of DC magnetic and AC electric fields neutral particles (atoms,molecules,nano-size particles etc.) nearby interface move with permanent velocity along the surface. The driving force depends on non-linear dynamical properties of polarization of the particles and a coupling betw…
We present results of molecular-dynamics simulations for a nonentangled polymer melt confined between two completely smooth and repulsive walls, interacting with inner particles via the potential U(wall)=(sigma/z)(9), where z=/z(particle)-z(wall) and sigma is (roughly) the monomer diameter. The influence of this confi…
Thermal treatment of Zn(NH3)(4)2+ precursor in ethanol solvent led to the formation of the tubular ZnO which exhibited strong ultraviolet photoluminescence around 385 nm at room temperature; TEM images showed the hollow tubules with approximately 450 nm in diameter and approximately 4 microns in length were built up b…
Adsorption in spherical cavities is studied by the nonlocal density functional theory (NLDFT). Theoretical results are compared with experimental data on ordered nanoporous materials with cubic Pm 3 n (SBA-1, HMM-3), cubic Im 3 m (SBA-16), and 3D hexagonal P 6 3 / mmc (SBA-2, SBA-12) cagelike structures. Quantitative…
The low-temperature alloying of Fe-Ag nanoparticles entrapped within thermally evaporated fatty acid films by a novel ion exchange technique is described. Nanoparticles of iron and silver were grown in thermally evaporated stearic acid (StA) films by sequential immersion of the film in solutions containing Fe 2+ ions…