Magnetism, superconductivity and coupling in cuprate heterostructures probed by low-energy muon-spin rotation

We present a low-energy muon-spin-rotation study of the magnetic and superconducting properties of YBa2Cu3O7/PrBa2Cu3O7 trilayer and bilayer heterostructures. By determining the magnetic-field profiles throughout these structures we show that a finite superfluid density can be induced in otherwise semiconducting PrBa2Cu3O7 layers when juxtaposed to YBa2Cu3O7 "electrodes" while the intrinsic antiferromagnetic order is unaffected.Comment: 10 pages, 9 figures; figure 9 corrected in version

Effect of the medium on the acid-base properties of α-aminophosphoryl compounds

Structural thermodynamic analysis of the acidity of α-aminophosphoryl compounds in water-isopropanol systems was carried out by means of evaluation of the Gibbs energies of transfer of species involved in protolytic equilibria. Protonated (deprotonated) forms of structurally diverse aminophosphoryl compounds similarly interact by the mechanism of specific and universal solvation with each of the water-isopropanol solvents (100, 50, and 25 vol % of water) in the reaction series used. For this reason, there are significant linear correlations between acidity parameters for various media, which makes possible successful predictions of the acid-base properties of structurally diverse compounds of the class studied in water-isopropanol media with various water contents. © 2005 Pleiades Publishing, Inc

Resonant multiple Andreev reflections in mesoscopic superconducting junctions

We investigate the properties of subharmonic gap structure (SGS) in superconducting quantum contacts with normal-electron resonances. We find two distinct new features of the SGS in resonant junctions which distinguish them from non-resonant point contacts: (i) The odd-order structures on the current-voltage characteristics of resonant junctions are strongly enhanced and have pronounced peaks, while the even-order structures are suppressed, in the case of a normal electron resonance being close to the Fermi level. (ii) Tremendous current peaks develop at $eV=\pm 2E_0$ where $E_0$ indicates a distance of the resonance to the Fermi level. These properties are determined by the effect of narrowing of the resonance during multiple Andreev reflections and by overlap of electron and hole resonances.Comment: 13 pages, 10 figure

STUDY OF NEPETAE CATARIAE HERBA FRUITS AS PROMISING MEDICINAL PLANT RAW MATERIAL

Nepetae catariae herba is used in the Russian Federation as spice. The chemical compounds of herb have been studied. This plant has been introduced into the culture. There are its domestic varieties. The fruits of the plant accumulate up to 25% of fatty oil and contain specific laballenic acid, which has a wide range of antimicrobial and fungicidal actions. The yield of fruit crops is 5–6 c/ha.The aim is to study some criteria for the standardization of the quality of Nepetae catariae herb as a new medicinal plant raw material.Materials and methods. The studied fruits are from the biological collection of Federal State Budgetary Institution of All – Russia Research Institute of Medicinal and Aromatic Plants. Binocular magnifier brand MBS-10 and Axioplan 2 imaging microscope by Carl Zeiss were used. The sample preparation was carried out according to the State Pharmacopoeia of the Russian Federation (XIV edition). Anatomical diagnostic features were studied in powder and cross section with staining reagents for the presence of some biologically active substances. Qualitative reactions were carried out with water and alcohol-water extracts from the fruits. The content of the lipid complex according to pharmacopoeia monograph 2.5.0035.15 has been determined.Results. A description of the external and diagnostic anatomical features is given. The main groups of biologically active substances and the content of the lipid complex in a possible new material – the fruits of Nepeta cataria – have been identified.Conclusion. The description of the external features of the fruit has been specified. For the first time, crushed fruits have been characterized. It has been established that the morphology of endocarp cells and seed embryo cells are best preserved in a mellow fruit. Physico-optical properties of cellular structures and the ability for basic microchemical reactions are preserved in all zones of pericarp and seeds. Qualitative reactions showed the presence of the following components in the fruits: saponins, flavonoids and a lipid complex. A dispersion composition has been studied. The yield of the lipid complex and its appearance have been determined. Fruits can be used as promising fat-oil raw materials. The results of the study can be used in drafting Pharmacovigilance Reference Document considering a promising type of medicinal plant raw material on the basis of Nepetae catariae herba fruits

Effect of the medium on the acid-base properties of α-aminophosphoryl compounds

Structural thermodynamic analysis of the acidity of α-aminophosphoryl compounds in water-isopropanol systems was carried out by means of evaluation of the Gibbs energies of transfer of species involved in protolytic equilibria. Protonated (deprotonated) forms of structurally diverse aminophosphoryl compounds similarly interact by the mechanism of specific and universal solvation with each of the water-isopropanol solvents (100, 50, and 25 vol % of water) in the reaction series used. For this reason, there are significant linear correlations between acidity parameters for various media, which makes possible successful predictions of the acid-base properties of structurally diverse compounds of the class studied in water-isopropanol media with various water contents. © 2005 Pleiades Publishing, Inc

Effect of the medium on the acid-base properties of α-aminophosphoryl compounds

Structural thermodynamic analysis of the acidity of α-aminophosphoryl compounds in water-isopropanol systems was carried out by means of evaluation of the Gibbs energies of transfer of species involved in protolytic equilibria. Protonated (deprotonated) forms of structurally diverse aminophosphoryl compounds similarly interact by the mechanism of specific and universal solvation with each of the water-isopropanol solvents (100, 50, and 25 vol % of water) in the reaction series used. For this reason, there are significant linear correlations between acidity parameters for various media, which makes possible successful predictions of the acid-base properties of structurally diverse compounds of the class studied in water-isopropanol media with various water contents. © 2005 Pleiades Publishing, Inc