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931.
932.
A N Dedenkov G A Petrova O A Smoryzanova T A Norets G V Vereshchagina 《Eksperimental?nai?a onkologii?a》1985,7(2):43-46
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. 相似文献
933.
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. 相似文献
934.
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. 相似文献
935.
Conclusions
Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 5, pp. 26–31, May. 2000. 相似文献
1. | A comparison of the efficiency of dispersion hardening of Ni-, Co-, and Fe-matrices has shown that steels are reinforced more strongly by coherent particles (the Mott-Nabarro model), which requires the lowes volume fraction of nitrides and the lowest concentration of the nitride-forming element in the alloy. In actual Ni- and Co-base alloys the highest hardening effect can be obtained due to incoherent particles too (the Orowan model) given that the nitride particles have optimum geometrical characteristics (the size and the distance between the particles). |
2. | The results of measurements of the microhardness of nitrided alloys agree well with the calculated data, which makes it possible to use models, in particular, for comparing the level of the hardening of individual alloys by various nitrides or segregations of different sizes. |
3. | The results of the evaluation of dispersion hardening by nitrides can be used for choosing nitriding regimes with the aim of providing maximum hardening |
936.
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. 相似文献
937.
938.
Muhammad Tariq Ying Li Wenxian Li Zihao Zhang Yemin Hu Mingyuan Zhu Hongming Jin Yibing Li Katerina Skotnicova 《Ceramics International》2018,44(1):71-75
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. 相似文献
939.
Pavlásková K Strnadová M Strohalm M Havlícek V Sulc M Volný M 《Analytical chemistry》2011,83(14):5661-5665
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. 相似文献
940.
A. D. Pomogailo A. S. Burlov N. D. Golubeva L. A. Petrova S. A. Mashchenko S. I. Pomogailo G. I. Dzhardimalieva A. D. Garnovskii 《Inorganic Materials》2011,47(8):876-883
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. 相似文献