Materials Literature
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On the basis of a phase field model previously proposed in Cahn et al. (Acta Mater. 45, 4397-4413 (1997)) to describe the phenomenon of diffusion-induced grain boundary motion (DIGM), we present a formal asymptotic reduction to a moving free-boundary problem. This problem is one of enhanced motion by curvature. The en…
The (betaalpha)8-barrel is the most versatile and most frequently encountered fold among enzymes. It is an interesting question how the contemporary (betaalpha)8-barrels are evolutionarily related and by which mechanisms they evolved from more simple precursors. Comprehensive comparisons of amino acid sequences and th…
We have synthesized and investigated new 3-ring phenylacetylene liquid crystals with high birefringence values (Δn) to improve the nematic temperature range while retaining a high optical anisotropy. In the case of modifying the terminal ring, the introduction of branched alkoxy chains, fluorine or methyl groups shift…
A new series of achiral compounds with banana-shaped molecules ('E n ') has been synthesized and studied by the classical techniques (optical microscopy, differential scanning calorimetry, X-ray diffraction, miscibility studies and electro-optic investigations). The short homologues (E7-E10) give switchable smectic me…
A study was conducted to examine phosphorus (P) sorption and immediate desorption in 0.01 M CaCl2 in unmanured and manured grassland and arable soils after chemical treatment designed to remove organic matter [sodium hypochlorite (NaOCl)], aluminum (Al) and iron (Fe) oxides [dithionite-citrate], and acid soluble mater…
A series of intermolecular hydrogen bonding complexes, 2,2'-bipyridine: p- n-alkoxybenzoic acids (BP : nABA) was isolated from liquid crystalline p-n-alkoxybenzoic acids (nABA) (where n represents alkoxy carbon numbers, 3 to 10 and 12) and a non-mesogen, 2,2'-bipyridine (BP). The thermal and phase behaviour of these c…
We have synthesized and evaluated the physical properties of thiophenylacetylene and benzothiazolylacetylene derivatives in order to obtain higher Δn liquid crystals as compared with analogous phenylacetylene-based compounds. These new materials had poorer liquid crystallinity than the phenylacetylene derivatives. Exc…
A fluid smectic phase of a chiral bent-core liquid crystal was found to have a ground state structure that is anticlinic in tilt and ferroelectric in polar order, SmCAPF*. The layer chirality of this structure alternates from layer to layer despite their being composed of chiral mesogens. Observations of the optical s…
Propagation of Cooper pairs in carbon nanotubes in the presence of superconducting correlations is studied theoretically. We find that negative and positive currents induced by impurity scatterings between electrons and holes cancel each other, and the nonmagnetic impurity does not hinder the supercurrent in the regio…
The crystal structure of pentamethylcyclopentadienylsodium, [NaC10H15] (NaCp*), has been determined from high-resolution X-ray powder diffraction. The compound crystallizes in space group Cmcm with lattice parameters a = 4.61030 (3), b = 16.4621 (3), c = 14.6751 (2) A, V = 1113.77 (4) A(3) (Z = 4). NaCp* forms polymer…
Poly(aspartic acid) (PAA) hydrolase was purified from Sphingomonas sp. KT-1 (JCM10459). The purified hydrolase degraded thermally synthesized PAA to oligomers. The molecular mass of PAA hydrolase was 30 kDa and the isoelectric point was 8.9. The optimum values of pH and temperature for PAA degradation were 10.0 and 40…
The synthesis, thermal behavior, and bulk microstructure of fluorinated new liquid-crystalline polyacrylates containing spaced fluoroalkylphenyl units in the side chains were studied. While in polyacrylates poly (1) and poly (2) there was a 4-(perfluorooctylethoxy)phenyl benzoate unit, i.e., a two-phenyl mesogenic cor…
Infrared spectroscopy coupled with adsorption of probe molecules such as CO and NO was used to investigate the surface adsorption properties of reduced Ru and Ru−Pt/NaY catalysts. CO adsorption at room temperature on the monometallic catalyst yielded three main bands at 2145, 2088, and 2031 cm -1, which were assigned…
The nanostructure deformation mechanism of a predrawn and annealed poly(ether ester) (PEE) thermoplastic elastomer comprising poly(butylene terephthalate) as hard segments and poly(ethylene glycol) as soft segments of a weight ratio 57/43 was studied by means of synchrotron radiation. For this purpose a recently propo…
The structure of Langmuir monolayers containing either a lipidated poly(ethylene glycol) (PEG-lipid) or a lipidated peptide (peptide-amphiphile) or a binary mixture of both was studied using neutron reflectivity. The PEG portion of the PEG-lipid extends into the water, forming dense polymer “brushes”. The PEG volume f…
Reflux-treated poly(methylsilane) (PMS) at 420−570 K improves its ceramic yield dramatically. This efficient process was investigated by TG, GC, 29 Si, 13 C, and 1 H NMR, and FT-IR methods. The structural transformation process of the PMS polymer consists of three stages. In the first stage below 500 K, PMS forms Si−S…
X-ray emission spectroscopy has been applied to examine the electronic structure of onion-like carbon (OLC) generated by the annealing treatment of nanodiamonds (ND). The C Kα spectra of OLC produced in the temperature range of 1600−1900 K were found to be markedly different from the spectrum of particles formed at 21…
The crystal structure of hexagonal ytterbium manganese oxide, YbMnO3, has been refined at room temperature. It is isomorphous with YMnO3. The Mn ions lie near the centre of a trigonal bipyramid. Although the Yb ions lie on threefold axes, the apical oxygen ions are at dissimilar distances, leading to ferroelectric be…
The two metal sites in cadmium substituted beta-lactamase from Bacillus cereus 569/H/9 have been studied by NMR spectroscopy ((1)H, (15)N, and (113)Cd) and PAC spectroscopy ((111m)Cd). Distinct NMR signals from the backbone amides are identified for the apoenzyme and the mononuclear and binuclear cadmium enzymes. For…
In the preceding paper of this series we studied the effect of several oils of different chemical structure on the foaming properties of sodium dodecylbenzenesulfonate solutions. A straightforward correlation was found between the foam stability and the so-called “entry barrier”, which prevents the emergence of pre-em…