Materials Literature
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The ability of MP2, B3PW91 and PBE0 methods to produce reliable predictions in structural and spectroscopic properties of small selenium-halogen molecules and cations has been demonstrated by using 6-311G(d) and cc-pVTZ basis sets. Optimized structures and vibrational frequencies agree closely with the experimental in…
Abstract The solubility of ethylene in toluene and in toluene (90 wt %)/styrene–butadiene rubber (SBR; 10 wt %) solutions was determined because the solubility data were of interest for the kinetic study of the metallocene‐catalyzed homopolymerization of ethylene and the copolymerization of ethylene with α‐olefins. Th…
We present studies of magnetic circular dichroism in Cr $2p$ resonant photoemission of epitaxial $\mathrm{Cr}{\mathrm{O}}_{2}$ thin films. The results reveal that the occupied Cr $3d$ bands center at an energy of 1 eV below the Fermi level, and that photoemission spectral weight originating from Cr $3d$ is weak at the…
Abstract Summary: A novel ABC triblock copolymer with a rigid‐rod block was synthesized by atom transfer radical polymerization (ATRP). First, a poly(ethylene oxide) (PEO)‐Br macroinitiator was synthesized by esterification of PEO with 2‐bromoisobutyryl bromide, which was subsequently used in the preparation of a poly…
We have studied the optical and electrical properties of two bent-core substances with an azo linkage in their cores. Pump-probe laser studies, direct textural observations, and spectrophotometric recordings show an initial decrease of light transmission, which at larger light intensities (approximately 1 mW/mm2) is f…
Onconase (ONC), a member of the RNase A superfamily extracted from oocytes of Rana pipiens, is an effective cancer killer. It is currently used in treatment of various forms of cancer. ONC antitumor properties depend on its ribonucleolytic activity that is low in comparison with other members of the superfamily. The m…
Recognition with a twist: The acid-initiated polymerization of dipeptide-derived isocyanides (see scheme) is found to be an exceptionally stereospecific process that requires a helical template. The reaction is very sensitive to the acid concentration. At high acid concentrations, the template is destroyed and a compe…
The deck is stacked in favor of future photonic devices. Novel photochromic crystals comprise alternating layers of two conformations of diarylethene 1 a. Irradiation with UV light induces isomerization of only one conformer to the blue-colored, closed-ring form, 1 b. This selective reactivity is ascribed to the diffe…
The resistivity of thin ${\mathrm{La}}_{0.7}{A}_{0.3}\mathrm{Mn}{\mathrm{O}}_{3}$ films $(A=\mathrm{Ca},\mathrm{Sr})$ is investigated in a wide temperature range. The comparison of the resistivities is made among films grown by different techniques and on several substrates allowing to analyze samples with different a…
[reaction: see text] A chiral periodic mesoporous organosilica (ChiMO) was prepared, in which a 1,2-bis-(ureido)cyclohexyl linker (38 wt %) is introduced into the walls of the hybrid organic-inorganic material. This silica was used as a host for 11-formyl-12-methyldibenzobarrelene (2), and the stereoselectivity of the…
[structure: see text] Rod-shaped 2,3-di-alkoxytetracenes, soluble in common organic solvents, have been synthesized and studied for their gelling ability in organic solvents and their unusual UV-visible spectroscopic properties.
Abstract Thin and wide ZnO nanobelts doped with 5 atom % tin have been achieved under different flowing atmosphere. Photoluminescence measurements show a blue shift in the near band edge (NBE) emission spectrum compared to a bulk single crystal of ZnO and the intensity ratio of the NBE to the green emission of these S…
We have performed a systematic molecular dynamics study of the competition between crack growth and dislocation emission from a crack tip. Two types of boundary conditions are adopted: either planar extension or boundary displacements according to the anisotropic mode-I asymptotic continuum solution. The effects of te…
The adsorption of volatile organic compounds (VOCs) on activated carbon, silica gel, and type 13X synthetic zeolite was measured by the method of gravimetric adsorption. The selected VOCs were oxygenated hydrocarbons including methyl acetate, ethyl acetate, propyl acetate, butyl acetate, isopropyl acetate, and isobuty…
Abstract The chemical polymerizations of pyrrole in the presence of acetophenone and formaldehyde, cyclohexanone, acetaldehyde, and formaldehyde, cyclohexanone and formaldehyde, cyclohexanone, resorcinol, and formaldehyde, cyclohexanone and lignosulfonate formaldehyde, and cyclohexanone, pyrrole, and formaldehyde were…
[structure: see text] The atropisomers of 5,10,15-tris(o-aminophenyl) corrole (alphabetaalpha, alphaalphabeta, and alphaalphaalpha) are metastable at room temperature as a result of the low rotational barrier of the o-aminophenyl pickets adjacent to the bipyrrole moiety. Atropisomer enrichment of TAPC was required for…
The dielectric properties of $\mathrm{Ba}\mathrm{Ti}{\mathrm{O}}_{3}$ thin films and multilayers are different from bulk materials because of nanoscale dimensions, interfaces, and stress-strain conditions. In this study, $\mathrm{Ba}\mathrm{Ti}{\mathrm{O}}_{3}∕\mathrm{Sr}\mathrm{Ti}{\mathrm{O}}_{3}$ multilayers deposi…
Aufgewickelt: Das Abschälen eines Apfels liefert ein helixförmiges Band, das wieder um den Apfel gewickelt werden kann. Eine solche Schale lässt sich im molekularen Maßstab erhalten, indem man eine Helix mit reduziertem Durchmesser an beiden Enden verwendet, die sich wie eine Kapsel verhält und einen kleinen Gast wie…
Licht steuert das Resultat einer stereoselektiven Reaktion. Nur in seiner offenen Form kann der gezeigte Chelat-Kupfer(I)-Komplex seine Chiralität auf die Cyclopropanierung von Styrol mit Ethyldiazoacetat übertragen. Einstrahlung von UV-Licht löst die Ringschlussreaktion des Liganden aus, die ihn wirkungslos macht.
We present a novel method for the preparation of ultrasmall Au/CdSe core/shell particles. Au-Cd bialloy particles of 4.7 nm diameter were prepared as the precursor. The Cd component in the precursor reacted with the Se source at a temperature of 205 degrees C and was heated to 250 degrees C, leading to formation of a…