Materials Literature
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The electrooxidation behavior of thiophene and 3-methylthiophene on a Pt surface in an acetonitrile + tetrabutylammonium tetrafluoroborate solution were investigated. The electropolymerization of these monomers was studied in neutral, acidic, and basic media. The effects of thiophene concentration and the added acid w…
Using the full-potential linearized augmented-plane-wave (FLAPW) method, the mechanism of the rutile-CaCl 2 phase transition of RuO 2 and the phase stability of β-PtO 2 are investigated. The local density functional calculations predict quantities such as lattice constants, bulk moduli, and phonon frequencies in good…
An optical microscopy study and a micro-Raman spectroscopy study were carried out on polyethylene samples subjected to an environmental stress crack resistance (ESCR) test. The aim was to elucidate the molecular deformation mechanisms associated with the failure process. It has been shown that in the early stages of t…
The epoxidation of trans-cyclooctene (trans-1) with the MTO/H(2)O(2), MTO/UHP, and NaY/MTO/H(2)O(2) oxidants leads to a mixture of trans/cis-olefins 1, trans/cis-epoxides 2, and the cis-diol 3. While the oxygen transfer proceeds stereoselectively, the monoperoxo rhenium complex A, which is generated in situ during the…
Specimens treated with solutions of an epoxy analogue molecule, diethanolamine (DEA), have been studied by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF−SIMS). The initial substrates were of two different types: grit-blasted aluminum and aluminum coated with an organosi…
We report the first electron paramagnetic resonance studies of single crystals and powders of Pr 0.6 Ca 0.4 MnO 3 in the 300-4.2 K range, covering the charge-ordering transition ( T co ) at ~240 K and antiferromagnetic transition ( T N ) at ~170 K. The asymmetry parameter for the Dysonian single-crystal spectra shows…
The new nonadentate tripodal ligand trenphen (tris[(1,10-phenanthroline-2-carboxamido)-ethyl]amine) has been synthesized by condensation of tren [tris(2-aminoethyl)amine] with an excess of 1,10-phenanthroline-2-carboxylic acyl chloride. The ligand trenphen and its lanthanide complexes (Sm, Nd, Eu, Tb, and Lu) have bee…
We have re-investigated the high pressure behaviour of berlinite AlPO 4 (α-AlPO 4 ) with x-ray diffraction using a powerful synchrotron x-ray source SPring-8. Our results show that it transforms to a crystalline phase beyond ~13 GPa. Our data seem to be consistent with a CrVO 4 type of structure in the Cmcm space grou…
4-Substituted pyridine-2,6-dicarboxylic acids, (E)-dipicH2, and 4-substituted pyridine-2,6-bis(thiocarboxylic) acids, (E)-pdtcH2, (E = OCnH2n + 1, SCnH2n + 1) have been synthesized and used as O,N,O- and S,N,S-pincer ligands with palladium. In the fourth coordination site the complexes bear 4-decyloxy-4'-stilbazole (L…
We study nonaqueous emulsions that are composed of liquid crystal and silicone oils. New surfactant molecules are specifically synthesized to stabilize these emulsions. The behavior of the present surfactants is reminiscent of the behavior of classical surfactants used for aqueous emulsions. Depending on their affinit…
A series of segmented polyurethanes was prepared from the new commercial product KRASOL LBH (linear liquid polybutadiene terminated with secondary hydroxy groups), aromatic diisocyanates, and an aliphatic low-molecular-weight diol. Three types of networks were prepared, with the nature of the crosslinks varied from pu…
Inelastic neutron scattering, supported by IR and Raman spectroscopy, has been used to observe a decreasing Pd−H bond strength in a series of four low-valent palladium−hydrogen complexes in the solid-state hydrides: K 2 [Pd(II)H 4 ], Li 2 [Pd(0)H 2 ], Na 2 [Pd(0)H 2 ], NaBa [Pd(0)H 3 ], and Ba 2 [Pd(0)H 4 ] . Further,…
Ultrasound radiation was used to prepare Eu 2 O 3 dd in zirconia and yttrium-stabilized zirconium (YSZ) nanoparticles. Europium oxide was also coated on the surface of submicron spherical zirconia and YSZ, which were fabricated by wet chemical methods. The coating process also used ultrasonic waves. Time decay measure…
Enzymatic degradation of a series of polyesters prepared from 1,4:3.6-dianhydro-D-glucitol (1) and aliphatic dicarboxylic acids of the methylene chain length ranging from 2 to 10 were examined using seven different enzymes. Enzymatic degradability of these polyesters as estimated by water-soluble total organic carbon…
The controlled and reversible formation of transiently soluble alkanethiolate- and tiopronin-monolayer-protected cluster (MPC) aggregates is demonstrated by using Cu 2+ −carboxylate chemistry to form cluster−Cu 2+ −cluster linkages. The aggregation process and its reversibility were monitored using UV−vis and FTIR spe…
Ein elektronischer Multiplexschalter molekularer Größenordnung wurde mit einem vierkernigen FeII-Komplex des [2×2]-Gittertyps verwirklicht. Bei den vier Metallionen ist es möglich, durch Änderung von Temperatur, Druck und Licht schrittweise zwischen High-Spin- und Low-Spin-Zustand zu schalten (siehe schematische Darst…
The nature of the singlet and triplet excited states of a series of meso -to- meso ethyne-linked bis(porphyrin) compounds was probed by electronic absorption, polarized pump−probe fluorescence, electron paramagnetic resonance (EPR), electroabsorption (Stark), and transient triplet−triplet absorption spectroscopic meth…
Non-conventional mechanisms have been recently invoked in order to explain the ferromagnetic ground state of A2Mn2O7 pyrochlores (A=Y, In, Lu and Tl) and the puzzling decrease of their Curie temperatures with applied pressure. Here we show, using a perturbation expansion in the Mn-O hopping term, that both features ca…
We present ab-initio studies of band offsets, formation energy, and stability of (100) heterojunctions between (Zn,Be)(Se,Te) zincblende compounds, and in particular of the lattice-matched BeTe/ZnSe interface. Equal band offsets are found at Be/Se and Zn/Te abrupt interfaces, as well as at mixed interfaces, in agreeme…
Previously, one of the authors has suggested [Phys. Essays, vol. 6, 554 (1993); vol. 10, 407 (1997)] a mechanism of the particle motion within the framework of a vacuum regarded as an original cellular medium, i.e. quantum aether. The existence of special elementary excitations of the aether medium -- inertons -- arou…