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We have studied the structure and proton conductivity of rhombohedral La6−xMoO12−δ (x = 0.5, 0.6, 0.7, 1) lanthanum molybdates prepared via mechanical activation of lanthanum and molybdenum oxides, followed by thermal annealing at 1650 °C. The La6−xMoO12−δ (x = 0.5, 0.6) materials were phase-pure and had a complex rhombohedral structure (R1). An increase in the molybdenum concentration leads to a decrease in the degree of rhombohedral distortion and proton conductivity in the La6−xMoO12−δ (x = 0.5, 0.6, 0.7, 1) series. The proton conductivity at the optimal composition La6−xMoO12−δ (x = 0.5) is ~4.0 × 10−5 S/cm at 500 °C in wet air. A comparative analysis shows that, in the Ln6−xMoO12−δ (Ln = La, Nd, Sm, Gd, Dy, Ho, Er, Tm, Yb; x = 0–1) series, proton conductivity decreases with the Ln ionic radii decreasing regardless of the structural type. Because of this, the high proton conductivity is demostrated by the stable La6−xMoO12−δ (x = 0.5, 0.6) materials, with an inherently deficient oxygen sublattice, which crystallize in a large-volume, complex rhombohedral cell (R1).

Staphylococcus aureus is an extremely infectious and malignant pathogen among many bacteria species. The aim of this work is to provide a robust classification model that would be able to identify S. aureus independent of the culture growth stage and the variations in bacteria concentration in suspension and also one that would be able to identify the pathogen among both taxonomically close species of the same genus and taxonomically distant species of different genera, using Fourier transform infrared spectroscopy (FTIR). In total, the spectra of 141 isolates of 17 bacteria have been used. Based on a combination of principal component analysis (PCA) and linear discriminant analysis (LDA), an identification model providing 100% sensitivity and 98% specificity was built. Inherent reliability and flexibility of the model have been shown. The proposed method of analysis allows us to get closer to the diagnostic requirements in the field of clinical microbiology, and it can be utilized for typing of other pathogenic bacteria species.

Stabilized fluorites and pyrochlores with different types of substitution in the (Nd2O3 − ZrO2 system (NdZrO)) have been studied by Raman spectroscopy, X-ray diffraction, and impedance spectroscopy methods. Ionic and proton conductivity maps for 9 compositions in the NdZrO system are presented. Oxygen partial pressure measurements show a typical ionic conductor behavior, with a significantly increase of conductivity for (Nd2−xZrx)Zr2O7+x/2 (x = 1.27) fluorite and (Nd2−xZrx)Zr2O7+x/2 (x = 0.4, 0.2) pyrochlores. For the same compositions the strong luminescence was observed. Strong luminescence and high oxygenion conductivity of these solid solutions can be associated with the presence of phases with the different degree of structural disorder (tetragonal phase, fluorite) in local nanodomains in fluorite or pyrochlore matrix in the ZrO2 − Nd2Zr2O7 region. Really, Raman spectra of (Nd2−xZrx)Zr2O7+x/2 (x = 0.5 − 0.2) solid solutions demonstrated the fluorite + pyrochlore structural type in the short-range order. Fluorite nanodomains in pyrochlore matrix (ZrO2 – Nd2Zr2O7 region) resulting from an order–disorder transition can only be detected at a radiation wavelength comparable to the fluorite nanodomain size. Thus, using Raman spectroscopy the broad isomorphism range in the ZrO2 – Nd2Zr2O7 system has been shown to be nonuniform. 371C-9F16-EBDE | Eduarda Gomes N/A

Plasminogen being a precursor of plasmin, a serine protease which plays a fundamental role in the intravascular thrombolysis. For the first time, by using high-resolution mass spectrometry, data were obtained of oxidative modifications of the plasminogen molecule under induced oxidation. The FTIR data show that under oxidation on the protein, its secondary structure also undergoes the rearrangements. The high tolerance of plasminogen to oxidation can be due to both the closed conformation and the ability of some Met residues to serve as ROS trap.

Large number researches with constructional steels used in nuclear reactjrs with heavy liquid-metal heat-transfer agents, have shown, that using of pulse intense electron beams (PIEB) including precoated with Al layer may be the most perspective meanse to improve operational characteristics of these steels. In report it ispresented description of experimental facility for practical realization of modification process of fuel element cladding surface, having radially converging PIEB with the electron source 100 cm long. The source consists of a cathode, a control grid and an anode, which is a treated target. Here they are presented the results of the first stage of experimental researches of the operation of this source. Design of the cathode of described electron source differs essentially from cjn-struction of previously used uncontrollable multipoint cathode. In new version of the cathode as an emitter of electrons it is used plasma indused by large quantities (2400 pieces) of the vacuum-arc discharge gaps arranged uniformly on surface of the cilindrical base plate. Whole assemblage of the discharge gaps consists of the cells each including four point electrodes and one cruciform discharge electrode in common. On surface of the cilindical target having diameter of 10 mm it was achieved density of electron beam energy of 30 J/cm2 on length not less 50 cm. They are shown the ways to increase the parameters of electron beam facility.