Materials Literature
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The electrical properties of Cu-substituted Ni–Mn ferrite Ni1–xCuxMnyFe2–yO4 (with 0.0 ≤ x ≤ 1.0 and y = 0.6) are investigated by ac conductivity measurements in the frequency range 102–105 Hz and over the temperature range 300–730 K. The results obtained for these materials reveal a semiconductor-to-metallic transiti…
Abstract The preparation and properties of a series of nanocomposite materials obtained using different organically modified montmorillonite clays with a simple epoxy resin are reported. Dynamic mechanical thermal analysis is used to assess the effect of the incorporation of the clay platelets into the matrix of the p…
The synthesis, optical properties, and solid-state structures of a series of o-(aryleneethynylene) oligomers containing three to seven aryl units is described. The main chain in all examples is composed of between one and five 4,5-dimethoxybenzene rings which are capped on each end by 2-pyridyl rings. These oligomers…
A force field model of phosphorus has been developed based on density functional (DF) computations and experimental results, covering low energy forms of local tetrahedral symmetry and more compact (simple cubic) structures that arise with increasing pressure. Rules tailored to DF data for the addition, deletion, and…
Whereas the $^{23}\mathrm{Na}$ spin-lattice relaxation rate ${T}_{1}^{\ensuremath{-}1}$ of microconfined ${\mathrm{NaNO}}_{2}$ in the ferroelectric phase is similar to the one of bulk ${\mathrm{NaNO}}_{2}$, there is a striking difference in the paraelectric phase. Instead of decreasing, the relaxation rate here increa…
Discrete nickel catalyst nanoparticles (NP) have been used to grow isolated single-walled carbon nanotubes by chemical vapor deposition (CVD). Atomic force microscopy (AFM), transmission electron microscopy (TEM) and micro-Raman spectroscopy are used to characterize these as-grown, isolated nanotubes. Using a conventi…
A method of free energy calculation is proposed, which enables to cover a wide range of pressure and temperature. The free energies of proton-disordered hexagonal ice (ice Ih) and liquid water are calculated for the TIP4P [J. Chem. Phys. 79, 926 (1983)] model and the TIP5P [J. Chem. Phys. 112, 8910 (2000)] model. From…
Periodic DFT calculations have been performed to investigate the adsorption, activation, and reactivity of N 2 O on a Rh(111) surface. Several adsorption modes in a narrow range of energies have been found. The most stable situation corresponds to a weak bonding (0.39 eV) via the N-terminal atom on top of a Rh atom, w…
Abstract Polyamide‐11 (PA11)/clay nanocomposites were prepared by in situ intercalative polymerization. The crystal morphology and crystallization kinetics of these nanocomposites were investigated via polarized light microscopy (PLM), small‐angle laser scattering (SALS) and differential scanning calorimetry (DSC). PA…
A procedure for the Raman spectra calculation of vitreous and molten silicates was presented in this paper. It includes molecular dynamics MD simulation for the generation of equilibrium configurations, Wilson's GF matrix method for the calculations of eigenfrequencies and corresponding vectors, electro-optical parame…
Two paralogous groups of liver fatty acid-binding proteins (FABPs) have been described: the mammalian type liver FABPs and the basic type (Lb-FABPs) characterized in several vertebrates but not in mammals. The two groups have similar sequences and share a highly conserved three-dimensional structure, but their specifi…
The reaction of Fe(III) with Na(+) and K(+) salts of the trivacant [alpha-SiW(9)O(34)](10)(-) ligand have been investigated at pH 6 and pH 1. A new dimer, [(alpha-SiFe(3)W(9)(OH)(3)O(34))(2)(OH)(3)](11-) (1), is synthesized by reacting Na(7)H(3)[alpha-SiW(9)O(34)] or K(10)[alpha-SiW(9)O(34)] with exactly 3 equiv of Fe…
This paper reports a theory for the dielectric relaxation of dimeric mesogenic molecules in a nematic liquid crystal phase. Liquid crystal dimers consist of two mesogenic groups linked by a flexible chain. Recent experimental studies [D. A. Dunmur, G. R. Luckhurst, M. R. de la Fuente, S. Diez, and M. A. Perez Jubindo,…
Surface-enhanced Raman scattering (SERS) spectra of 4-methylpyridine are obtained in silver hydrosol and compared with those obtained in an electrochemical cell. The use of density functional theory (DFT) calculations allows one to interpret the SERS data and collect information on the structures of the complexes form…
The mixing effect of alkaline earth metal halides on ammonia absorption−desorption behavior was studied to develop a new ammonia storage material to be used for the pressure-swing absorption method. The halide mixtures with different cations (having a common anion) did not form the solid solution after drying of the m…
Novel cyclen-based phenylboronate ligands and their corresponding Eu(3+) complexes have been examined as glucose sensors using chemical exchange saturation transfer (CEST) MR imaging for detection. Two isomeric bis-phenylboronate complexes, Eu(4) and Eu(10), and a mono-phenylboronate complex, Eu(12), had been prepared…
The mechanism of formation of two different cubic mesoporous silica materials formed with Pluronic triblock copolymers is investigated with in situ time-resolved small-angle synchrotron X-ray scattering, in situ time-resolved 1H nuclear magnetic resonance, and time-resolved transmission electron microscopy. The materi…
Clusters of metal atoms at a fixed size can assume different structural arrangements, known as isomers, which may have nearly the same energy. Therefore, at given experimental conditions distribution of these isomers can be present. While the size selection is a relatively common technique, the isomer selection is not…
Molecular dynamics atomistic simulations of solid and liquid benzene have been performed, employing a model intermolecular potential derived from quantum mechanical calculations. The ab initio database includes approximately 200 geometries of the benzene dimer with interaction energies computed at the MP2 level of the…
Abstract Modification of isotactic polypropylene (iPP) with two nucleation agents, namely 1,3:24‐bis(3,4‐dimethylobenzylideno) sorbitol (DMDBS) (α‐nucleator) and N , N ′‐dicyclohexylo‐2,6‐naphthaleno dicarboxy amide (NJ) (β‐nucleator), leads to significant changes of the structure, morphology and properties. Both nucl…