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21.
Fluorapatite-containing glass ceramics were synthesized on the basis of the glass-forming system SiO2–Al2O3–P2O5–CaO–CaF2. The introduction of phosphorus and fluorine containing materials, as well as the specific regime of heat treatment of the glasses gave glass ceramic materials with crystalline phases of the apatite group—fluorapatite (Ca10(PO4)6F2), apatite (Ca3(PO4)2), vitlokite (Ca9P6O24), etc. The X-ray phase analysis showed that the main phase in all the glass ceramic samples was fluorapatite. The phase composition, structure and some of the basic properties of the glass ceramic samples were determined.  相似文献   
22.
The magnetic state of Y1 ? x Tb x Mn6Sn6 (with x ≤ 0.25) alloy is studied at different temperatures and magnetic fields by neutron diffraction. The alloy with x c = 0.22 exhibits an incommensurate-to-commensurate structure phase transition. The transition is accompanied by a decrease in the unit-cell volume. The weak dependence of the intensity of satellites on the x concentration and the monotonic displacement of their angular positions with increasing x allow us to conclude that the antiferromagnet → ferrimagnet transition occurs through the uniform magnetic state. The incommensurate phase in YMn6Sn6 exhibits four satellites, which are observed in the low-angle range of X-ray diffraction pattern and demonstrate different behavior with changing temperature. At 293 K, the antiferromagnet → ferromagnet transition in the Y1 ?x Tb x Mn6Sn6 compound can be induced by applied magnetic field, in particular, the field μ0 H = 0.3 T induces the transition in Tb0.15Y0.85Mn6Sn6.  相似文献   
23.
Results of a study of tube specimens cut from hot-water boilers show that film-forming octadecyl amine (ODA) used in the process of preservation removes deposition from the surface of the metal. An ODA film is preserved on the surface after repeated washing of the latter with hot water. The concentration of chlorides at the surface of the metal after treatment with ODA is lower than before the treatment. __________ Translated from élektricheskie Stantsii, No. 11, November 2005, pp. 15–18.  相似文献   
24.
The hydrogenation properties of HfNi and Hf2Ni7 intermetallics were investigated at the constant pressure of 1 bar and in the temperature ranges 373-573 K for HfNi and 323-473 K for Hf2Ni7. The kinetic parameters, rate constants and activation energies of the absorption processes were determined. Maximal hydrogen absorption, i.e., number of hydrogen atoms absorbed per metal atom, H/M, are 1.05 and 0.04 achieved at 373 K for HfNi and Hf2Ni7, respectively. Multiple hydriding/dehydriding was found to influence the improvement of the kinetic parameters. XRD and SEM methods were used to investigate the structural and morphological changes of the samples due to hydrogen absorption. The thermodynamic parameters of hydriding together with the structural properties of the intermetallics and their hydrides, calculated using the full-potential linearized augmented plane waves (FP-LAPW) code based on the density functional theory (DFT), were utilized for the sake of explaining the experimental investigations.  相似文献   
25.
A combined spectrometer is composed of a wide-aperture magnetic spectrometer with proportional chambers and a -spectrometer based on a Ge(Li) detector. The respective momentum and the angular resolutions of the magnetic spectrometer are FWHM/p(%) = 0.59p (GeV/c) + 1.1 and 0.5–1 mrad; its average efficiency for 0°–5° angles is 85%. The energy resolution of the -spectrometer is 8 and 16 keV for 0.5- and 2.0-MeV photons, respectively; the average angular acceptance is 1.5 msr.  相似文献   
26.
Methods of the experimental diagnostics and control of the misorientation angle for single-crystal HPHT (High Pressure High Temperature) diamond substrates are discussed. Such substrates are used for the homoepitaxial growth of doped and undoped CVD diamond layers. The formation of singular (001) terraces on the surface of HPHT diamond after microwave-discharge-plasma etching in pure hydrogen or a hydrogen–oxygen mixture is observed. This phenomenon can be used for rapid determination of the substrate misorientation and to improve the control precision of the deviation angle during substrate polishing, or for obtaining large singular (001) areas of single-crystal diamond substrates.  相似文献   
27.
It is known that the growth factor activates appropriate membrane receptors which become starting points of cascades of protein-protein interactions leading to cellular response. Recent data suggest that different signalling pathways may cross-talk during the cellular response. Here we show that phosphoinositide-specific phospholipase C gamma 1, one of the key elements in phosphoinositide pathway of signal transduction, is physically associated with members of the STAT pathway. The precipitation of phospholipase C gamma 1, using polyclonal antibody in A-431 cells, leads to co-immunoprecipitation of STAT1 alpha and STAT1 beta, as well as STAT3. The formation of such complexes was observed in both unstimulated and EGF stimulated cells. The participation of SH3-domains in the formation of such complexes is discussed.  相似文献   
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