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Pantev A Valcheva R Danova S Ivanova I Minkov I Haertlé T Chobert JM 《International journal of food microbiology》2003,80(2):145-152
Lactic acid bacterium isolated from Bulgarian cheese and identified as Enterococcus faecium produces a small hydrophobic peptide substance (enterococcin A 2000) with broad spectrum of antimicrobial activity. The wide range of enterococcin antibacterial activity of this compound against Gram-positive, as well as against some Gram-negative bacteria, suggests a single mechanism of action. The mode of action of enterococcin A 2000 was studied in intact liver mitochondria and synthetic phospholipid liposomes used as model systems. Enterococcin A 2000 stimulated the ATPase activity in intact mitochondria. The kinetic curve of ATP hydrolysis differed from that obtained in presence of dinitrophenol (DNP) and showed a character similar to the ATP hydrolysis in the presence of classic ionophores. Enterococcin A 2000, when bound to synthetic phospholipid liposomes, permeabilized liposomes liberating the marker carboxyfluorescein (CF). 相似文献
96.
Thermal and elastic properties of poly(vinyl chloride) (PVC) + chlorinated polyethylene (CPE) blends
Robert?D.?MaksimovEmail author Tatjana?Ivanova Janis?Zicans Sophia?N.?Negreeva Egils?Plume 《Materials Research Innovations》2003,7(5):326-330
Eight types of PVC + CPE blends with different weight ratios (PVC/CPE = 100/0, 90/10, 80/20, 60/40, 40/60, 20/80, 10/90, and 0/100) are tested. Data on the heat conductivity, thermal diffusivity, and heat capacity of the blends investigated are reported. Primary attention is paid to the structural approach for effective elastic constants: bulk, shear, and Young's modulae. The blends are considered as random mixtures of two isotropic constituents. It is found that the elastic moduli may be well represented by the Kerner and Budiansky equations. 相似文献
97.
Sb2Te3–Bi2Te3 crystals (25–60 mol % Bi2Te3) doped with Bi2Se3 and excess Te were studied with the aim of identifying the optimal compositions for the p-legs of low-temperature coolers. The crystals were grown by the floating-crucible technique. Their transport properties were studied in the range 100–400 K. By measuring axial thermopower profiles, it was shown that increasing the Bi2Te3 and Bi2Se3 contents of the crystals has an adverse effect on their homogeneity. Crystals were prepared with a carrier concentration in the range (1–5) × 1019 cm–3 and a thermoelectric power above 200 V/K at room temperature and the highest thermoelectric figure of merit at temperatures below 200 K. The maximum temperature drops and thermoelectric figures of merit were calculated for low-temperature stages of magnetothermoelectric coolers with hot-junction temperatures of 200 and 170 K and Bi–Sb n-legs. 相似文献
98.
Prevalence of risk of ischemic heart disease, such as nutrition and dyslipoproteinaemias are discussed. The interrelation of these risk factors with blood lipids was examined. It was found that risk factors are widespread, and population has low knowledge about their significance. Food, contained surplus of cholesterol, saturated fats, carbohydrates and deficiency of polyunsaturated fat acids increased atherogenic blood lipids and decreased antiaterogenic lipoproteins. 相似文献
99.
New Np(VI) and Pu(VI) dimolybdates Rb2NpO2(MoO4)2·H2O (I), Cs2NpO2(MoO4)2·H2O (II), Cs2PuO2(MoO4)2·H2O (III), and Rb2PuO2(MoO4)2·H2O (IV) were synthesized under hydrothermal conditions. The crystal structures of the compounds were determined, and their absorption spectra in the UV, visible, and IR ranges were measured. The compounds crystallize in the monoclinic system. Their crystal structure is based on [AnO2(MoO4)2]n2n– anionic layers (An = Np, Pu) formed by (AnO2)O5 pentagonal bipyramids and MoO4 tetrahedra, sharing common vertices. Each An atom in the layer is bonded to other five An atoms via MoO4 tetrahedra with the formation of a 43432 network. The effect of the ionic radius of the outer-sphere cation on the parameters of the crystal structure and features of the absorption spectra is discussed. 相似文献
100.
L. D. Ivanova 《Inorganic Materials》2011,47(9):965-970
Rhenium-doped higher manganese silicide based materials have been prepared by hot pressing. It has been shown that the pressing
temperature of the materials can be lowered by adding titanium as a reductant or by sonication during pressing. The average
thermoelectric figure of merit of the materials in the temperature range 600–900 K is Z ≅ 0.7 × 10−3 K−1. 相似文献