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Monitoring was conducted for the structural steel types used in the Republic of Kazakhstan for construction of buildings using the metal frames. For each type of steel it was the first time determined for hardness specification by Brinell methods. Hardness specification is applied to determine the yield strength, breaking strength and the relative deformation at rupture. These parameters of structural steel are considered to determine compliance with requirements of the National Annex of the Republic of Kazakhstan Eurocode 1993, which is used to design metal structures in the Republic of Kazakhstan. Previously, such issues have not been solved yet. Practical significance of the work consists in possibility of using local types of steel for design according to Eurocode 1993.

The intent of this work is to investigate the influence of scandium occupying dodecahedral and octahedral positions of the garnet crystal lattice on the aspects of vacuum sintering of the optical ceramic Y3–xScxAl2–yScyAl3O12:Cr as well as on its optical and luminescent properties. As part of this investigation, YSAG:Cr optical luminescent ceramic was produced for the first time from ceramic powders of metastable compositions with a high content of scandium in the dodecahedral position. The compositions considered were described by the general formula Y3–xScxAl2–yScyAl3O12, where 0.12 ≤ x ≤ 1.50 and 0.08 ≤ y ≤ 1.00 p.u. [physical units] with total scandium content 0.12 – 1.70 p.u. The following investigations of YSAG:Cr ceramic samples were conducted: x-ray diffractometry, measurement of the shrinkage kinetics of ceramic compacts using dilatometry, and investigation of the morphology and elemental composition of the ceramic surface by means of scanning electron microscopy. The spectra of light transmission and luminescence were measured. It was shown that ceramic made from compositions with scandium content predominating in the dodecahedral positions reach maximum density at lower temperatures compared to compositions containing a larger amount of scandium in the octahedral positions. It was found that as the sintering temperature of YSAG:Cr ceramic increases, compositions with a high content of scandium in the dodecahedral position become unstable. [ABSTRACT FROM AUTHOR]

The phase composition and spectral-luminescent properties of samples of a luminescent ceramic, based on oxide compositions with makeup described by the general formula Y2.98–xCexAl5.02O12, where x = 0.05, 0.10, 0.20, 0.30, 0.45, and 0.60 formula units (f.un), were investigated. It is demonstrated that the phase composition of ceramic powders depends substantially on the cerium concentration and the calcination atmosphere. It was ascertained that the maximum concentration of cerium cations in the garnet lattice on calcination in air is equal to about 0.1 f.un, and in an argon and hydrogen atmosphere approximately 0.16 f.un The photoluminescence of ceramic samples excited by a 445 nm laser was investigated. It is shown that ceramic samples obtained by sintering in argon and hydrogen have a higher luminescence intensity compared to samples synthesized in vacuum. The possibility of shifting the wavelength of the maximum luminescence intensity from 546 to 570 nm by changing the cation composition and the sintering conditions of the ceramics was demonstrated. It is shown that oxidative annealing of ceramic samples adversely affects the intensity and position of luminescence maxima in highly cerium-doped oxide compositions Y2.98–xCexAl5.02O12. [ABSTRACT FROM AUTHOR]

The energy loss spectrum of 180 GeV muons has been measured with the 5.6 m long finely segmented Module 0 of the ATLAS hadron Tile Calorimeter at the CERN SPS. The differential probability dP/dv per radiation length of a fractional energy loss v = ΔΕμ/Εμ has been measured in the range 0.025 ≤ v ≤ 0.97; it is compared with theoretical predictions for energy losses due to bremsstrahlung, production of electron-positron pairs, and energetic knock-on electrons. The iron elastic form factor correction ΔelFe = 1.63 ± 0.17stat ± 0.23Syst±0.200.14theor to muon bremsstrahlung in the region of no screening of the nucleus by atomic electrons has been measured for the first time, and is compared with different theoretical predictions.