Materials Literature
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Cu/Mg/Al catalysts obtained by controlled calcination of hydrotalcite-type (HT) anionic clays may be new interesting and cheap catalysts for the selective catalytic reduction (SCR) of NO by NH 3 . In this paper the ammonia adsorption and oxidation on Cu x Mg 0.710 - x Al 0.290 catalysts ( x = 0.022, 0.046, and 0.072,…
We found three smectic phases, SmX1, SmX2 and SmX3, in achiral compounds with banana shape. The SmX1 phase has a biaxial single molecular layer, along which polarization exists. The polarization precesses along the layer normal, and is aligned by applying an electric field. The spontaneous polarization is about 60 nC/…
Thermotropic liquid-crystalline behavior of phosphonium salts, which are structurally simple amphiphiles with positively-charged phosphorus atoms and without rigid cores, was evaluated by differential scanning calorimetry, polarizing optical microscopy, and X-ray diffractometry. The phosphonium salts were found to sho…
Surface modification with hydrophilic polymers has been beneficial in improving blood compatibility of biomaterials. Formation of dense and tightly-bonded surface layers may prevent plasma protein adsorption owing to steric repulsion. General conditions for formation of layers, protecting blood components from direct…
A new aromatic gelator, p -octylbenzohydroxamic acid (OBHA), forms thermoreversible networks for concentrations as low as ca. 0.1% in several organic liquids. In the context of organogelators, the OBHA originality consists of a chemical structure that combines aromaticity with hydroxyl and amine groups. Preliminary rh…
In plant and mammalian cells, excess lysine is catabolized by a pathway that is initiated by two enzymes, namely, lysine-ketoglutarate reductase and saccharopine dehydrogenase. In this study, we report the cloning of an Arabidopsis cDNA encoding a bifunctional polypeptide that contains both of these enzyme activities…
The room-temperature structures of Pb(Zr x Ti1−x )O3 ceramics are shown to be tetragonal for x ≤ 0·52 and rhombohedral for x ≥ 0·530 while both the rhombohedral phase (R-phase) and the tetragonal phase (T-phase) coexist at x = 0·525 corresponding to the morphotropic phase boundary (MPB). Ceramics with x = 0·530 and 0·…
Abstract Alkali metal intercalated compounds of a layer structured perovskite, KCa2Nb3O10, have been prepared by the reaction with n-butyllithium or alkali metal azides, AN3 (A = Li and Na). The magnetic susceptibility measurements showed that the compounds became superconductors with transition temperatures ranging f…
meso -α,α,α,α-Tetrakis(2-hydroxy-1-naphthyl)porphyrin ( 1 ) and 5,15- cis -bis(2-hydroxy-1-naphthyl)-10,20-diphenylporphyrin ( 2 ) were prepared as receptors for ubiquinone analogues. UV−vis, IR, NMR, and X-ray crystal data reveal that these porphyrins bind a series of quinones with a cofacial structure linked by hydr…
HslVU in Escherichia coli a new two-component ATP-dependent protease composed of two heat-shock proteins, the HslU ATPase and the HslV peptidase which is related to proteasome beta-type subunits. Here we show that the reconstituted HslVU enzyme degrades not only certain hydrophobic peptides but also various polypeptid…
Group 6 metal atoms, generated by laser ablation, react with CO 2 to give the insertion products OMCO and O 2 M(CO) 2 (M = Cr, Mo, or W) which have been isolated in argon matrices and identified by the effects of isotopic substitution on their infrared spectra. These assignments have been supported by DFT calculations…
A chemically induced dynamic electron spin polarization (CIDEP) study has been accomplished on radical-excited triplet pairs (RTP) in systems of metalloporphyrins, MgTPP, ZnTPP, and ZnOEP, and pyridine-substituted nitronyl nitroxide radicals, nit-R (R = o-py, m-py, and p-py), by X- (9.5 GHz) and W-band (95 GHz) time-r…
Information concerning the oxidation of o-xylene and naphthalene, the two main processes for producing phthalic anhydride, is updated and analyzed. New techniques for the preparation of catalysts, all based in the impregnation method and involving the control of parameters such as pH and ionic strength of solutions, a…
PbZr 0.56 Ti 0.44 O 3 (PZT) epitaxial ferroelectric thin films on a LaAlO3 (100) substrate, covered by a metallic oxide electrode La0.5Sr0.5CoO3 (LSCO) are demonstrated in this work. The films are fabricated by the sol–gel method and effort was focused on thermal processing to obtain the desired epitaxial heterostruct…
The molecular orientation and aggregation behavior of 5-(4- N -octadecyl-pyridyl)-10,15,20-tri- p -tolylporphyrin (porphyrin 338a) in mono- and multilayer Langmuir−Blodgett (LB) films have been investigated by employing ultraviolet−visible (UV−vis) and infrared (IR) spectroscopies. It has been found that the porphyrin…
Two microscopic techniques, muon spin relaxation and neutron diffraction, including small-angle neutron scattering (SANS), have been used to probe into the relevant mechanisms that determine the macroscopic behavior in the series $({\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Tb}}_{x}{)}_{2/3}{\mathrm{Ca}}_{1/3}{\mathrm{M…
Biochemical and enzymatic characterization of the novel proprotein convertase rat PC7 (rPC7) was carried out using vaccinia virus recombinants overexpressed in mammalian BSC40 cells. Pro-PC7 is synthesized as a glycosylated zymogen (101 kDa) and processed into mature rPC7 (89 kDa) in the endoplasmic reticulum. No endo…
Abstract High resolution and high efficiency planar display, one of the national priorities for advanced technologies and commercial applications, require highly efficient phosphor materials with crystalline monodispersive fine particles [1,2]. Europium oxide activated yttrium oxide (Y2O3:Eu) is a potential red-emissi…
Experimental current-voltage and current-light intensity characteristics of Schottky diodes with the structure: metal (Al) - porous silicon - n-type silicon substrate are presented. The measurements are carried out with a pulsed current in the high current densities conditions, which usually lead to irreversible break…
It is shown that the nonstationary thermoelectric power with characteristic rise and fall times of the order of seconds in multilayered structures with p - n junctions can be several orders of magnitude greater than the stationary thermoelectric power in a homogeneous semiconductor. This effect can be observed in poly…