Materials Literature
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Abstract A multiarm star polymer was synthesized through the grafting of oligo polyglycol with urethane chain end units onto the core of hyperbranched polyglycerol (HPG), which was obtained through the cationic ring‐opening polymerization of glycidol. Samples were characterized with 13 C NMR, liquid chromatography/mas…
Using CaCO 3 , metal oxides (all dissolved by nitric acid) and tetraethoxysilane Si(OC 2 H 5 ) 4 (TEOS) as the main starting materials, Ca 2 R 8 (SiO 4 ) 6 O 2 :A (R = Y,La,Gd;A = Eu 3+ ,Tb 3+ ) phosphor films have been dip-coated on quartz glass substrates through the sol–gel process. X-ray diffraction (XRD), atomic…
In this paper, we present an overview of recent progress in the development of the NASA Macro-Fiber Composite (MFC) piezocomposite actuator device. This will include a brief history of the development of the MFC, a description of the standard manufacturing process used to fabricate MFC actuators, and a summary of ongo…
The copper(I) bis(chelate) complex Cu(L(0))(2) has been prepared from 2,9-diphenethyl-1,10-phenanthroline and Cu(CH(3)CN)(4)BF(4). Derivative Cu(L(0))(2) has been characterized by NMR, UV-vis spectroscopy, and X-ray crystallography. Interestingly, owing to the presence of the ethylene linker, the interligand pi-pi sta…
The beta-clip fold includes a diverse group of protein domains that are unified by the presence of two characteristic waist-like constrictions, which bound a central extended region. Members of this fold include enzymes like deoxyuridine triphosphatase and the SET methylase, carbohydrate-binding domains like the fish…
Abstract In this paper, a rectangular waveguide and a nonraditive dielectric (NRD) waveguide, filled with anisotropic negative permittivity and permeability, are studied in detail. A general condition of the existence of TE and TM modes in these waveguides is derived. The unique characteristics of these waveguides are…
The ferromagnetic manganite ${\mathrm{La}}_{0.67}{\mathrm{Ca}}_{0.33}{\mathrm{MnO}}_{3}$ is systematically investigated below Curie temperature ${T}_{C}$ by measurements of internal friction ${Q}^{\ensuremath{-}1}(T),$ Young's modulus $E(T),$ resistivity $\ensuremath{\rho}(T),$ and magnetization $M(T).$ Accompanying s…
We have used spectroscopic methods to investigate the effect of cross relaxation on the 1470 and 1800 nm emissions in Tm 3+ :TeO 2 –CdCl 2 glass for Tm 3+ ion concentrations of 0.05, 0.1, 0.25, 0.5 and 1.0 mol%. The emission spectra obtained under 800 nm excitation reveal the existence of energy transfer via cross rel…
Abstract A bis(phenylamino)disulfide was prepared through the reaction of S 2 Cl 2 with aniline, and its configuration was confirmed with elemental analysis, Fourier transform infrared (FTIR), Fourier transform Raman (FT‐Raman), and 1 H NMR spectroscopy. A novel conducting polymer, poly[bis(phenylamino)disulfide] (PPA…
We demonstrate a model for determining the adsorptive and catalytic properties of strained metal surfaces based on linear elastic theory, using first-principles calculations of CO adsorption on Au and K surfaces and CO dissociation on Ru surface. The model involves a single calculation of the adsorption-induced surfac…
The intercalation of polypyrrole (ppy) into hexagonal mesostructured carbon at 6.80–12.6 wt.‐% levels results in substantial shrinkage of the framework structure (Δ d 100 = 0.8–1.0 nm) and the pore size (from 3.7 nm initially to 2.9–2.5 nm upon ppy binding). The surface areas (718–960 m 2 g –1 ) and electrical conduct…
Suspensions of anisometric particles in the nematic phase of a liquid crystalline host solvent were prepared. We chose Claytone AF, a commercial quaternary ammonium surfactant treated montmorillonite, with an aspect ratio of up to 1:2000, and dimethyldioctadecylammonium bromide treated Laponite, with an aspect ratio o…
Comparison of two protein structures often results in not only a global alignment but also a number of distinct local alignments; the latter, referred to as alternative alignments, are however usually ignored in existing protein structure comparison analyses. Here, we used a novel method of protein structure compariso…
Tin-oxide films were grown on Pt(111) substrates by oxidation of Sn/Pt surface alloys using ${\mathrm{NO}}_{2}$ exposures or by deposition of Sn in an ${\mathrm{NO}}_{2}$ ambient gas. Structural aspects of monolayer tin-oxide films were reported previously [Phys. Rev. B 64, 245402/1 (2001)]. At elevated substrate temp…
Microdomain structures and phase transitions of binary and ternary mixtures of polystyrene−polyisoprene−polystyrene (PS−PI−PS) triblock copolymer Vector 4111 (containing 18% PS) and the corresponding homopolymers were investigated in thin films by atomic force microscopy and in bulk by small-angle X-ray scattering. Th…
Poly(phenylenevinylene) polymers, functionalized with either amine or carboxyl acid groups (see Figure), have been synthesized and assembled using layer‐by‐layer deposition. This hydrogen‐bonding‐driven self‐assembly produces conjugated polymer multilayer films with molecular‐level controlled thickness and architectur…
The adsorption of O2 on the Pt(111) surface, with particular emphasis on the influence of substrate temperature, has been studied by infrared reflection absorption spectroscopy (IRAS). In the temperature range 30-90 K the IRAS spectra reveal three different molecular adsorption states. A physisorbed state appears belo…
Thin films of asymmetric diblock copolymers have been used as scaffolds to define an ordered array of nanometer‐scale reaction vessels in which high density arrays of silicon oxide nanostructures (see Figure) are produced by exposure to silicon tetrachloride. Such site‐specific silicon oxide nanostructures could have…
Pressure solution creep is one of the possible processes of mechano‐chemical deformation that controls porosity and permeability variations in the upper crust. The three‐dimensional geometry of the porous network of halite aggregates was imaged during compaction driven by pressure solution creep using X‐ray synchrotro…
New silole compounds based on the 7-azaindolyl and 2,2‘-dipyridylamino groups, 1,1-dimethyl-2,5-bis(4- N -7-azaindolylphenyl)-3,4-diphenylsilole ( 1 ), 1,1-dimethyl-2,5-bis(4‘- N -7-azaindoylbiphenylyl)-3,4-diphenylsilole ( 2 ), 1,1-dimethyl-2,5-bis( p -2,2‘-dipyridylaminophenyl)-3,4-diphenylsilole ( 3 ), and 1,1-dime…