Materials Literature
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The collective transport of charge density waves (CDW) converts into an ordinary current at the contacts with a normal metal. In the present work this conversion is proposed to proceed via the process of phase slippage (PS). The CDW in the quasi-one-dimensional system with a nested Fermi surface and impurities is desc…
The crystal structure of the title compound, [Cu(bipy)2][PF6]2(1), has been determined by X-ray crystallographic methods, using diffractometer data collection; the structure was solved by the heavy-atom method and by successive Fourier syntheses. Compound (1) crystallises in the tetragonal space group I41/acd, a= 16.2…
More than 40 protein species including RNA polymerase were found to be phosphorylated in Escherichia coli on analyses of 32P-labeled cell lysates by single and two-dimensional gel electrophoresis and autoradiography. The protein species and the level of phosphorylation varied depending on the cell growth phase. With […
We report high resolution X-ray scattering measurements of the smectic phases and phase transitions in the material N-(4-n-butyloxy-benzylidene)-4-n-heptylaniline (40.7) (I → N → Sm A → Sm C → Sm B). For the nematic to smectic A transition we have measured the critical exponents γ = 1.45 ± 0.03, ν ∥ = 0.78 ± 0.02, and…
A selection of aliphatic alkenes, substituted styrenes, and cis-stilbene has been epoxidised with aqueous NaOCl, employing two different porphyrins, Mn(TPP)OAc and Mn(TMP)Cl, as catalysts. Large increases in reaction rate, product selectivity, and stereoselectivity are found with the bulkier TMP ligand. The results ar…
The adsorption of acridine orange by H-, Na-, Mg-, Al- and Cu-montmorillonite has been studied by visible and infrared spectroscopy and by X-ray diffraction methods. Adsorption of the dye takes place by the mechanism of cation exchange. The maximum amount of adsorbed dye depends on the exchangeable metallic cation, de…
A picosecond spectroscopic study of trans 1,1′-biindanylidene (‘‘stiff’’ stilbene) has exposed a transient absorption at 351 nm which is not an electronically excited state of the trans or cis forms. The signal strength increases with decreasing viscosity in a manner that is consistent with the decay of the excited tr…
Collective magnetic excitations are supported by multiple ferrite layers. The character of magnetostatic waves is calculated for such systems and is illustrated for three different layers variously spaced (accurate control of the delay characteristics is shown to be possible) as well as for very many similar layers eq…
Abstract Monodisperse polyacrolien (PA) microspheres were obtained by a single step process via two mechanisms: (a) aqueous polymerization of acrolein under alkaline conditions and (b) aqueous radical polymerization of acrolein by irradiation with a cobalt source. The diameter of the former microspheres can be varied…
Temperatures of the nematic → isotropic (TNI) and smectic-A → nematic (TSN) transitions in p-quaterphenyl, p-quinquephenyl and p-sexiphenyl have been determined from differential scanning calorimetry measurements carried out on the pure compounds and their binary mixtures. Both transitions are located below the meltin…
Three anhydrous forms (forms I, II, and III), dihydrate (form IV) and monoacetonate (form V) of carbamazepine were prepared and characterized by elemental analysis, infrared spectrum, X-ray powder diffraction, differential scanning calorimetry (DSC), and differential thermal analysis (DTA). The phase transition of the…
The character and occurrence of mist, hackle, and crack-branching features on ceramic fractures are reviewed and possible mechanisms for causing these features are discussed. Besides glass and polycrystalline fractures, substantial attention is paid to fractures of ceramic crystals, for which new data are presented an…
Low-density structures such as colloidal aggregates become increasingly easy to deform mechanically as their size increases. We use recently-proposed scaling properties of such aggregates to investigate the effects of thermal fluctuations and of gravitational forces on such structures. For typical colloidal aggregates…
The conducting organic salt N-methylphenazinium tetracyanoquinodimethanide can be used as an electrode for the oxidation of NADH at a sufficiently rapid rate to be a good detector in an enzyme coupled sensor.
Recently, the transform method for calculating Raman excitation profiles (REP’s) from the absorption spectrum has been extended to include both the Condon and non-Condon sources of scattering. In the present work, this theory is applied to REP’s in the Soret region of ferrocytochrome-c, where data are presented for tw…
The self-trapping of exciton in the CDW phase of one-dimensional many-electron system with short-ranged electron-phonon(e-p) and electron-electron(e-e) interactions is studied by a variational method for exciton and in the adiabatic limit for phonons, so as to clarify its lattice relaxation after the light excitation.…
The present paper states very briefly the main steps leading to the technique of scanning electron microscopy (SEM) of vascular corrosion casts. From the terms presently used (injection method, microcorrosion cast, injection replica, vascular corrosion cast, vascular cast) the use of "vascular corrosion cast" for lymp…
The anchoring strength coefficient B is measured as a function of temperature using a Freedericksz technique in a very thin (l < 2.5 μm) surfactant-treated cell of methoxybenzylidene butylaniline (MBBA). In the nematic phase this parameter varies from approximately 0.065 to 0.013 erg/cm2 for TNI - 20 °C < T < TNI. The…
The elastic energy expression of de Gennes for the non-chiral and chiral smectic-C phases is reformulated, and it is shown that the maximum size of a uniformly oriented sample is limited, not only by the chiral helix but also by a spontaneous bend of the smectic layers. A description of the flexoelectric effects is gi…
We present experimental and theoretical studies of the structures and transitions of the molecular orientation field of a smectic C* liquid crystal in the surface-stabilized geometry. The experimental results show that structures having from two to six stable orientation configurations are possible. The optical proper…