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A powerful, simple and fast technique for non-destructive multi-element analysis of materials is energy dispersive X-ray fluorescence (EDXRF) technique. This method is based on radioisotope excited energy dispersive X-ray fluorescence (EDXRF) spectrometry and does not require any type-standards. For these reasons, the EDXRF method was chosen in this paper to analyse the different types of stainless steel (SS) samples. After non-destructive multi-element
Read moreThe material for experiments was an aluminum alloys series 7xxx obtained by thermo-mechanical processing. We studied the influence of different artificial aging parameters on mechanical characteristic and corrosion of Al-Zn-Mg-Cu-alloy. The Al alloys was solution treated at 475 +/- 5 oC for 60 minutes, quenched in water 40-60oC and artificial aging at 120, 150, 180, 210oC at different time of aging (60, respectively 300, 540, 720 minutes). After
Read moreA poly(bisphenol A)cyanurate (PCy) network was modified by a hydroxy-terminated oligoester, poly(butylene glycol adipate), PBGA, by polycyclotrimerization of bisphenol A dicyanate in the presence of the oligoester. The modified networks with PBGA content from 5 to 20% (w/w) were characterized by a combination of FTIR, DSC, TMA, TGA, impact testing and sol-gel analysis. It has been established that almost whole of the PBGA was chemically incorporated
Read moreThe paper presents the experimental results concerning fabrication through powder metallurgy (P/M) of new ecological aluminum matrix composites (AMC) at a low cost for automotive industry applications. The difficult compaction and sintering of aluminum powder products and especially of powders from aluminum composite mixtures reinforced with hard ceramic particles require complex phenomenon's analysis which occurs during materials' fabrication. Thus
Read moreAl-Cu matrix composite materials with 5-20 wt. proportions of SiC hard particles and unreinforced Al-Cu alloys obtained by powder metallurgy (P/M), in the same homogenization (20 r.p.m., about 7 hours)- pressing (450 MPa for composites) - presintering (300-420 degrees C/30 min/H(2)) conditions but at different sintering temperatures (520-620 degrees C/60min/H(2), furnace cooling) were analyzed in terms of microstructural and physical characteristics.
Read moreWe present an intensive radio and X-ray monitoring campaign on the 2009 outburst of the Galactic black hole candidate X-ray binary H1743-322. With the high angular resolution of the Very Long Baseline Array, we resolve the jet ejection event and measure the proper motions of the jet ejecta relative to the position of the compact core jets detected at the beginning of the outburst. This allows us to accurately couple the moment when the jet ejection
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