Materials Literature
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Biologists often gain structural and functional insights into a protein sequence by constructing a multiple alignment model of the family. Here a program called Probe fully automates this process of model construction starting from a single sequence. Central to this program is a powerful new method to locate and align…
ADVERTISEMENT RETURN TO ISSUEPREVCommunicationNEXTA Combinatorial Approach for Polymer DesignStephen Brocchini, Kenneth James, Varawut Tangpasuthadol, and Joachim KohnView Author Information Department of Chemistry Rutgers, The State University of New Jersey New Brunswick, New Jersey 09803 Cite this: J. Am. Chem. Soc.…
Bimetallic, oxalate-bridged compounds with bi- and trivalent transition metals comprise a class of layered materials which express a large variety in their molecular-based magnetic behavior. Because of this, the availability of the corresponding single-crystal structural data is essential to the successful interpretat…
Illumination of polyoxotungstates generates a short-lived excited state which decays to form the reactive intermediate wO that is responsible for subsequent transformation of organic substrates. It is shown by laser flash photolysis that wO is formed with a quantum yield of 0.6 and that it survives for ca. 55 ns in de…
About 8 years ago, Brinker and Robinson [l] invented the first aliphatic polybenzimidazoles. Two years later, aromatic polybenzimidazoles with impressive thermal properties were synthesized by Vogel and Marvel [2, 3] at the University of Illinois and later at Du Pont. Since then, high performance polybenzimidazoles re…
ac electrical measurements are reported for the paraelectric phases of the ferroelectric CuInP2S6 and antiferroelectric CuCrP2S6. A complex permittivity analysis confirms previous dielectric results for CuInP2S6. Arrhenius behaviors with nearly identical activation energies were observed for the dc conductivities and…
In electrical insulation in high voltage equipment being serviced under dc stress, space charge is often present. This change greatly influences the electrical field. Quantitative knowledge about the presence of space charge is therefore needed. This paper describes the quest for useful measurement principles. One mea…
The electrochemical behavior of 55% Al-Zn coated steel sheet, on which a very thin polymeric film (≈ 1 μm) was applied, was studied using electrochemical impedance spectroscopy (EIS). Use of a straightforward electric model to analyze the spectra obtained with different polymer films allowed correlation of the coating…
The structure of the alkaline earth silicate glass CaSiO 3 has been investigated using a two-dimensional 29 Si NMR experiment that correlates the isotropic magic-angle-spinning (MAS) spectrum with an anisotropic off-magic-angle-spinning spectrum. Although the one-dimensional magic-angle-spinning (MAS) spectrum is comp…
Femtosecond measurements of transient absorption, bleach, and stimulated emission are used to study the excited-state dynamics of phthalocyanine tetrasulfonate (PcS 4 ) and zinc phthalocyanine tetrasulfonate (ZnPcS 4 ) in solution. In water the excited-state decay process is fast and dominated by energy relaxation due…
A series of layered magnesium organosilicate nanocomposites that contain covalently linked organic functionalities have been prepared by a one-step, direct synthesis procedure. The in situ reactivity of organic moieties (e.g., phenyl, thiol) within the layered inorganic−organic nanocomposites, as well as the potential…
Blends of synthetic atactic poly(3-hydroxybutyrate) (a-PHB) with a natural bacterial isotactic copolymer of 3-hydroxybutyrate with 3-hydroxyvalerate (PHBV) containing 10 mol % of 3HV units were prepared using a simple casting procedure. In the range of compositions explored (10−50% a-PHB), blends of bacterial PHBV and…
The phenomenological boundary conditions for the envelope wave function, which is applicable for contacts of semiconductors with the rather different crystal symmetry are proposed. It is shown that the boundary conditions are determined by the number of real values, which are independent of the electron energy. The nu…
A simple model of polymeric relaxation, associated with the electrochemical switching of polypyrrole films between their reduced (insulating) and oxidized (electronically conducting) states, offers a reasonably precise description of the form of chronoamperograms obtained after previous subjection of the polymer film…
The synthesis and characterization of a family of well-defined liquid crystal−coil (LC−coil) diblock copolymers have been carried out. The block copolymers in this study have been designed to have nearly identical molecular weight azobenzene-containing LC blocks in order to eliminate possible variations in LC behavior…
The novel monovinyl-functional silsesquioxane cage 1-(9-decenyl)-3,5,7,9,11,13,15-heptaethylpentacyclo[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxane has been prepared and copolymerized with ethene and propene. The monovinyl-functional spherosiloxane was obtained from the octahydridosilsesquioxane (HSiO 3/ 2 ) 8 via hydros…
Aggregation in the nondoped polyaniline, emeraldine base (EB), as observed by GPC in a N -methyl-2-pyrrolidinone (NMP) solution, was found to be closely related to the fraction of the imine nitrogen atoms in the nondoped polymer, i.e., to the oxidation state of the polymer. As EB was reduced to leucoemeraldine base (L…
Dielectric, ferroelectric and piezoelectric pŕoperties of a BNT-based solid solution, (1-x)(Bi1/2Na1/2)TiO3-xNaNbO3, that is, Bi(1-x)/2Na(1+x)/2 Ti1-x Nb x O3 (BNTN-100x), are studied from the viewpoint of a new group of lead-free piezoelectric ceramics. The conventional ceramic fabricating technique was used to prepa…
The corrosion behavior of copper in aqueous solutions of different pH values was investigated using electrochemical and surface analysis methods. It was shown that the corrosion mechanism changed with pH and was associated with morphology of the surface films formed. In solution of pH 3, the copper surface was covered…
The syntheses of two new derivatives of 3,4-ethylenedioxythiophene (EDOT), specifically 5-octyldioxeno[2,3- c ]thiophene (EDOT-C 8 ) ( 2 ) and 5-tetradecyldioxeno[2,3- c ]thiophene (EDOT-C 14 ) ( 3 ), and their polymers are reported in this paper. Cyclic voltammetry of 2 and 3 in 0.1 M TBAP/CH 3 CN show irreversible m…