Experimental determination of human erythrocyte membrane permeability coefficients for a series of amides

Erythrocyte membrane permeability coefficients have been determined for a series of amides by a method based on the physical and mathematical modelling of hypotonic haemolysis process. The results show that penetration of the substances occurs by two alternative ways through aqueous pores formed by proteins and by the direct dissolving of the molecules in membrane lipids. This conclusion can be confirmed by the correlation analysis between permeability coefficients of native erythrocytes and those pre-incubated with the monosodium salt of p-chloromercuribenzenesulfonic acid (pCMBS), and the partition coefficients of the substances in hydrophilic-hydrophobic phases. Penetration of substances through hydrophilic channels is limited by the sterical factor and diameter in particular. Permeability coefficients for erythrocytes pre-incubated with pCMBS increase in an accordance with the rise of the partition coefficients with correlation coefficient of 0.94, thereby indicating a lipid route of permeation of molecules through erythrocyte membranes.     

Dopant-modulated pair interaction in cuprate superconductors

A comparison of recent experimental STM data with single-impurity and many-impurity Bogoliubov-de Gennes calculations strongly suggests that random out-of-plane dopant atoms in cuprates modulate the pair interaction locally. This type of disorder is crucial to understanding the nanoscale electronic inhomogeneity observed in BSCCO-2212, and can reproduce observed correlations between the positions of impurity atoms and various aspects of the local density of states such as the gap magnitude and the height of the coherence peaks. Our results imply that each dopant atom modulates the pair interaction on a length scale of order one lattice constant.     

Design of two-dimensional random surfaces with specified scattering properties

A method is proposed for designing a two-dimensional randomly rough Dirichlet surface that, when illuminated at normal incidence, scatters a scalar plane wave with a specified angular distribution of its intensity. The method is validated by computer simulation calculations.     

Surface Polaritons in GaAs/CdTe/PbTe Multilayer Structures

JETP Letters - Infrared spectra of reflection and attenuated total reflection of PbTe thin films deposited by molecular beam epitaxy on a GaAs/CdTe substrate have been measured. The high-frequency...     

Operators with an absolute functional calculus

We study sectorial operators with a special type of functional calculus, which we term an absolute functional calculus. A typical example of such an operator is an invertible operator A (defined on a Banach space X) considered on the real interpolation space (Dom(A), X) _θ,p where 0 < θ < 1 and 1 < p < ∞. In general the absolute functional calculus can be characterized in terms of real interpolation spaces. We show that operators of this type have a strong form of the H ^∞-calculus and behave very well with respect to the joint functional calculus. We give applications of these results to recent work of Arendt, Batty and Bu on the existence of Hölder-continuous solutions for the abstract Cauchy problem.     

Thermal properties of volatile ruthenium(III) complexes

Complexes of ruthenium(III) with the following beta-diketone derivatives: 2,4-pentanedione (Ru(acac)₃), 1,1,1,6,6,6-hexafluoro-2,4-pentanedione (Ru(hfac)₃), and 2-methoxy-2,6-dimethyl-3,5-heptanedione (Ru(mdhd)₃) were synthesized, purified, and identified by chemical analysis and melting points. By difference-scanning calorimetry (DSC) in vacuum the thermodynamic characteristics of melting processes were defined. Using the static method with quartz membrane zero-manometer, the temperature dependencies of saturated and unsaturated vapor pressure were obtained for Ru(hfac)₃. The standard thermodynamic characteristics of vaporization processes enthalpy ?H _T* and entropy ?S° _T* were determined.     

Approximate similarity of electrophysical and kinematic processes during pulsed corona discharges in strong electrolytes

Based on a theoretical method of dimensional and similarity analysis and on published experimental data on the dynamics of corona discharges in strong electrolytes, dimensionless numbers are found which make manifest the approximate similarity of electrophysical and hydro/gasdynamic phenomena. A physical experiment is carried out, and generalized time dependences are obtained for the current, voltage across the interelectrode gap, and plasma radius in terms of these similarity numbers. Zh. Tekh. Fiz. 69, 30–34 (May 1999)