Materials Literature
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An algorithm is presented for the accurate and rapid generation of multiple protein sequence alignments from tertiary structure comparisons. A preliminary multiple sequence alignment is performed using sequence information, which then determines an initial superposition of the structures. A structure comparison algori…
The structures observed for many inorganic solids are the result of a compromise between the conflicting requirements of chemical bonding and threedimensional geometry. The ideal chemical structure and bond geometry can be predicted using the bondvalence model which is developed in some detail. The constraints imposed…
Atomic and molecular size devices are the ultimate goal of those working on, for example, nanoscale patterning and templating techniques. The various approaches to nanophase materials with stringent requirements of size, shape, and dimensionality are discussed, recent highlights are described, and teh advantages to be…
Interest in the properties of thin-film organic materials, especially regard ing organized monoand multilayer assemblies, has grown enormously in recent years. The impetus for this renaissance-the relevance of such structures and materials to biological interfaces and membranes, corrosion protection, electrochemistry…
The results of X-ray structural, IR and Raman spectroscopic, and thermodynamic studies of alkali metal molybdates and tungstates A2MnO3n+1 (A = Li, Na, K, Rb, Cs; M = Mo, W) are reviewed and analysed. The dependence of the vibrational spectra, activation energies, and crystal lattice energies on features of the struct…
The collagenous dermis of the white rhinoceros forms a thick, protective armour that is highly specialized in its structure and material properties compared with other mammalian skin. Rhinoceros skin is three times thicker than predicted allometrically, and it contains a dense and highly ordered three-dimensional arra…
SrTiO3 thin films having perovskite structure were fabricated by sol-gel technique with a post-deposition rapid thermal annealing treatment at 550 °C for 60 s. The films exhibited good structural, dielectric, and insulating properties. The measured dielectric constant and loss factor at 100 kHz were 225 and 0.008, res…
Nuclear transport theory predicts the formation of unstable bubbles and rings in the central collision between equal-mass heavy ions. This phenomenon occurs around a beam energy of E/A\ensuremath{\approxeq}50 MeV/nucleon and is due to the compression of the nuclei in the early stage of the collision. As observable con…
The vibrational properties of ${\mathrm{Si}}_{1/2}$${\mathrm{Ge}}_{1/2}$ alloys are studied using first principles interatomic force constants. The effects of disorder are either simulated using large supercells or treated at the mean-field level by the coherent-potential approximation. The latter approach fails not o…
Positive muons injected into solid ${\mathrm{C}}_{60}$, ${\mathrm{K}}_{4}$${\mathrm{C}}_{60}$, and ${\mathrm{K}}_{6}$${\mathrm{C}}_{60}$ form vacuumlike muonium (${\mathrm{\ensuremath{\mu}}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$) with a (6--12)% probability. Observation of coherent spin precession of muonium es…
The gene encoding component S, the small subunit, of glutamate mutase, an adenosylcobalamin (coenzyme B12)-dependent enzyme from Clostridium tetanomorphum has been cloned and its nucleotide sequence determined. The mutS gene encodes a protein of 137 amino acid residues, with M(r) 14,748. The deduced amino acid sequenc…
Fatigue and retention characteristics of ferroelectric lead zirconate titanate thin films grown with Y-Ba-Cu-O(YBCO) thin-film top and bottom electrodes are found to be far superior to those obtained with conventional Pt top electrodes. The heterostructures reported here have been grown in situ by pulsed laser deposit…
Abstract For the purpose of flame retardation, nylon 6 textile was first hydroxymethylated and then the methylol group containing nylon 6 textile was finished with Pyrovatex CP at 160–170°C. The limiting oxygen index (LOI) value increased from 23.6 for the original textile to 31.4 for the modified one. The mechanism o…
Abstract Fiber melt spinning of poly(ethylene terephthalate) (PET) was studied via modification of threadline dynamics. Several techniques were implemented in the high‐speed spinning process for the judicious control of threadline dynamics. This included a thermal conditioning zone (TCZ) for controlling the threadline…
Abstract Transport properties of antioxidants in polymers have a very important role in their effectiveness. Lifetime of a product is strongly influenced by the physical loss of the stabilizer. The diffusion coefficient ( D ) and solubility ( S ) of Irganox 1010 in low‐density polyethylene (LDPE) were studied at 45 an…
Abstract The influence of counterions on the properties of aqueous dispersions of polyurethane (PU) anionomer have been investigated. The PU anionomers were prepared by polyaddition reaction of 4,4′‐methylenebis(phenylisocyanate) with poly(propylene glycol) (PPG), dimethylolpropionic acid (DMPA), and 1,4‐butanediol, f…
Abstract Porous poly(2‐hydroxyethyl methacrylate) (PHEMA) beads cross‐linked with ethylene glycol dimethacrylate (EGDM) were prepared by the suspension polymerization of the monomers in the presence of cyclohexanol or toluene as the diluents. A 20% aqueous NaCl solution containing MgCl 2 · 6H 2 O, bentonite, and gelat…
Abstract This chapter covers the field of channelling and its effects for electrons traversing thin crystals in the transmission geometry. Channelling effects in the reflection or RHEED geometry, where the beam makes a glancing angle with the crystal surface, are treated in Vol. 2, chapter 3. Backscattered channelling…
Saccharomyces cerevisiae has both cytoplasmic and mitochondrial C1-tetrahydrofolate (THF) synthases. These trifunctional isozymes are central to single-carbon metabolism and are responsible for interconversion of the THF derivatives in the respective compartments. In the present work, we have used 13C NMR to study fol…
An X-ray structure analysis of a crystal of mutant Asp229----Ala of cyclodextrin glycosyltransferase from Bacillus circulans (Ec 2.4.1.19) that had been shortly exposed to beta-cyclodextrin showed density corresponding to a maltose bound at the catalytic center. The crystal structure was refined to an R-factor of 18.7…