Materials Literature
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An isocitrate dehydrogenase (ICDH) with an unique coenzyme specificity from Acidithiobacillus thiooxidans was purified and characterized, and its gene was cloned. The native enzyme was homodimeric with a subunit of M(r) 45000 and showed a 78-fold preference for NAD(+) over NADP(+). The cloned ICDH gene (icd) was expre…
A new phosphate, Ca 9 FeD(PO 4 ) 7, with a whitlockite-like structure was synthesized by treating Ca 9 Fe(PO 4 ) 7 with D 2 at 820 K. Mössbauer spectroscopy showed that the oxidation state of Fe in Ca 9 FeD(PO 4 ) 7 is +2. Ca 9 FeD(PO 4 ) 7 was paramagnetic in a temperature range from 5 to 300 K with an effective magn…
Crystallization under shear of many different polypropylenes has been studied using a fiber pull-out device. It appears that growth can be considerably enhanced by flow. The best correlation is obtained with weight average molecular weight. Modeling the flow pattern gives access to the mechanical parameters at the gro…
Abstract Gas diffusion electrodes for electrochemical devices frequently consist of polytetrafluroethylene (PTFE) and carbon black‐supported catalysts. The hydrophilic or hydrophobic character determines the wetting behaviour, which is important for media transport in the gas diffusion electrodes. The main components…
A sol–gel‐derived Pb(Mg 1/3 Nb 2/3 ) 0.7 Ti 0.3 O 3 (PMNT) thin film was prepared using spin coating and a PbO cover coat technique. The amount of lead excess in the precursor solution had significant effects on the phase development and microstructure of the PMNT film. The PbO cover coat proved to be effective on sup…
The propagation of thermoelastic waves and phase-transition fronts is considered in a unified manner on the basis of thermodynamic consistency conditions following from the thermodynamics of discrete systems. Distinct consistency conditions are used in the bulk (for thermoelastic waves) and at the phase boundary (wher…
Various 2,2‘-bipyrroles N -substituted with alkyl, alkylsulfonate, or alkylammonium moieties have been anodically coupled to polymers. The polymers were characterized by cyclic voltammetry, UV−vis and FTIR spectroscopies, EQCM, and in situ conductivity. Coupling of dipyrroles instead of pyrroles minimizes the introduc…
The applicability of transmission electron microscopy (TEM) to determine polarity was examined for GaN, ZnO, AlN and GaAs. The adopted methods are the TEM–EDS (energy dispersive X-ray spectroscopy) and the conventional convergent beam electron diffraction (CBED) methods. TEM observations and dynamical electron diffrac…
A newly developed real time spectral birefringence technique was implemented to follow the coupled relationships between birefringence, true stress and true strain behavior of varying crosslink density natural rubber vulcanizates at room temperature. It was shown that the stress optical law is valid even at early stag…
The environmentally benign polymerization of aniline provided polyaniline with an emeraldine structure by using iron(III) and ozone which is easily converted from oxygen in air. The influence of the reaction temperature upon the molecular weight of the polyaniline in this system is different from that in the polymeriz…
We demonstrate that it is possible to achieve exceptionally fine control over the anchoring of liquid crystals via the use of semi-fluorinated self-assembled monolayers of varying spacer length. We use this approach to map the detailed shape of an anchoring transition surface in thermodynamic phase space and to explor…
Huygens's principle is used to derive equations for tracing the extraordinary ray in a uniaxial crystal when the crystal axis is normal to the refracting surface. Snell's law is used to trace ordinary rays that lead to an array of ordinary spherical wavelets centered on the refracting surface. Each spherical wavelet i…
This paper reviews studies on the optical properties of dielectric nanocrystals doped by rare-earth and transition-metal ions. Manifestations of small nanocrystal size in the optical properties of impurity ions are considered. Two types of phenomena are discussed: (i) those associated with modification of the vibratio…
The frequency of the R‐line luminescence from Cr 3+ ions in aluminum oxide is known to be sensitive to chromium concentration, stress, and temperature. In this work, the effect of simultaneously doping aluminum oxide with both Cr 3+ and other ions (Fe, Ti, Ni, or Y) on the R‐line frequency and intensity at room temper…
A model for the combined processes of quiescent and flow-induced crystallization of polymers is presented. This modeling should provide the necessary input data, in terms of the structure distribution in a product, for the prediction of mechanical properties and shape- and dimensional-stability. The model is partly ba…
Abstract The initial oxidation of Zr1Nb alloy in oxygen, water and hydrogen peroxide at room temperature has been studied by angle‐resolved x‐ray photoelectron spectroscopy (ARXPS). The clean surface of alloy has been prepared either by scraping under ultrahigh (10 −10 mbar) vacuum or by argon ion sputtering. The four…
The boron sillenite, up to now known as the 12:1 compound Bi24B2O39 in the system Bi2O3 – B2O3 andcrystallizing in the space group I23, melts incongruently at 655 °C only about 25 K above the eutectic tie line and corresponding to a steep liquidus line. Single crystals with dimensions larger then 1 cm 3 have been succ…
The orientation of the crystalline δ nanoporous phase in syndiotactic polystyrene films, obtained by different procedures, have been characterized. For both solution cast and biaxially stretched films a high degree of uniplanar orientation, corresponding to the tendency of the ac crystallographic planes, to be paralle…
Measurements of the temperature dependence of the thermal conductivity $\ensuremath{\kappa}(T)$ of the antiferromagnetic perovskites ${\mathrm{SmNiO}}_{3},$ ${\mathrm{CaMnO}}_{3},$ ${\mathrm{LaMnO}}_{3},$ and ${\mathrm{YCrO}}_{3}$ are compared to that of the nonmagnetic perovskite ${\mathrm{LaGaO}}_{3}.$ Whereas ${\ma…
New highly stable benzo-fused m-trifluoromethylphenyl porphyrazines and their complexes with Mg and In were synthesized by cross-condensation of phthalonitrile and bis(m-trifluoromethylphenyl)fumaronitrile. Their 1H and 13C NMR spectra were recorded and described. The Q- and B-bands in the UV/Vis spectra of the metal…