Distribution kinetics and metabolism of triiodothyronine and thyroxine in the organs and tissues of mice with transplanted Lewis carcinoma

A comparative analysis of triiodothyronine (T3) and thyroxine (T4) distribution in organs and tissues of tumour-bearing and intact mice conducted wih 125J labelled T3 and T4 has shown considerable differences in the accumulation character of these hormones in mice with Lewis carcinoma and in intact animals in the liver, kidneys, lungs, adrenal glands, lymphatic nodes. Low T3 and T4 concentration in the blood of tumour-bearing mice was observed during the whole period of study.     

Cathodoluminescence properties of yttrium aluminum garnet doped with Eu<Superscript>2+</Superscript> and Eu<Superscript>3+</Superscript> ions

Yttrium aluminium garnet (YAG) doped with Eu²⁺ and Eu³⁺ ions is very interesting as a phosphor for conversion of light-emitting diode light for white light sources. The europium ion occupies the structural position of yttrium in yttrium aluminium garnet and has valence state Eu³⁺. Our sample was doped with Zr⁴⁺, which is why some of the europium ions had valence state Eu²⁺. As a rule, luminescence of Eu³⁺ ions is observed in the orange and red range of spectrum. The luminescence of Eu²⁺ in yttrium aluminum garnet is characterized by an intensive broad band with maximum of intensity at about 560 nm (green color). In this work, we studied the intensity and decay time dependences on europium concentration, and the influence of excitation power density on the cathodoluminescence of the sample. The most interesting result is the change of visible cathodoluminescence color in dependence on the density of the exciting power. The text was submitted by the authors in English.     

Comparison of methods for forcing pulse linear electromagnetic motors

The method for forcing in the mode of the static inductive accumulator of magnetic energy is considered. For pulse linear electromagnetic motors used in impact devices, this method is shown to be advantageous as compared to the forcing method based on power supply from a source of increased voltage.     

Comparison of dispersion hardening by coherent and incoherent nitrides in nitriding of alloys based on iron, nickel, and cobalt

Conclusions  

Thermoelectric materials based on Sb<Subscript>2</Subscript>Te<Subscript>3</Subscript>-Bi<Subscript>2</Subscript>Te<Subscript>3</Subscript> solid solutions with optimal performance in the range 100–400 K

We have optimized the compositions of thermoelectric materials based on Sb₂Te₃-Bi₂Te₃ solid solutions using Czochralski-grown single crystals. The thermoelectric performance of Sb₂Te₃-Bi₂Te₃ solid solutions containing 0–100 mol % Bi₂Te₃ and Bi₂Te₃-Sb₂Te₃-Bi₂-Bi₂Se₃ solid solutions containing 2, 4, or 7 mol % Bi₂Se₃ has been investigated. The Bi₂Se₃-doped crystals are found to have higher thermoelectric figures of merit compared to the undoped crystals. The optimal crystal compositions are selected for different temperatures in the range 100–400 K.     

Ferromagnetic coupling of Fe3+-VO-Fe3+polarons in Fe-doped ZnO

Room temperature ferromagnetic Fe-doped ZnO with hexagonal wurtzite structure was synthesized by a hydrothermal method under 4 T high pulsed magnetic field. Detailed studies were carried out to survey the effect of magnetic field on morphological, structural and magnetic properties of samples. The results showed that the concentration of oxygen vacancies (VOs) and amount of Fe³⁺ doping in ZnO were improved due to the high magnetic field processing. It proposed that the inherent exchange interaction is mediated by magnetic ions (Fe³⁺) through VOs assist to produce bound magnetic polorans (BMPs), which is responsible for RTFM in Fe-doped ZnO matrix.     

Time-dependent oxidation during nano-assisted laser desorption ionization mass spectrometry: a useful tool for structure determination or a source of possible confusion?

This work reports on a new and extremely simple approach for determination of a double bond position by a laser desorption ionization mass spectrometry. It is solely based on the catalytic properties of nanostructured surfaces used in nanoassisted laser desorption ionization experiments. These surfaces can induce oxidation of analytes, which results in a mass shift that can be detected by mass spectrometry. If a site of unsaturation is oxidized and cleaved, the m/z difference is diagnostic of the position of a double bond. By demonstrating that the oxidation depends on the analyte surface dwell time, it was proven that it is caused by the surface activity and not by the laser desorption ionization process itself. Control matrix-assisted laser desorption/ionization (MALDI) experiment showed only a limited partial oxidation and no time dependency of the process. The ability to determine a position of a double bond was demonstrated on polyunsaturated phospholipids and cyclosporine A. In some other cases, however, the unexpected oxidation could cause confusion, as demonstrated for a glycosphingolipid from a porcine brain extract.     

Preparation of nanostructured materials through thermolysis of metal chelate complexes

We demonstrate that nanocomposites (metals and metal carbides and sulfides) can be produced by thermolysis (370 and 600°C) in a self-generated atmosphere using Cu(II), Co(II), and Ni(II) 2-hydroxy- and 2-N-tosylaminobenzaldehyde azomethine bis-chelates as precursors.