An investigation of the Al-Rh-Ru phase diagram above 50 at.% Al

Partial 1100, 1000, 900 and 700 °C isothermal sections of the Al-Rh-Ru phase diagram were determined. The isostructural binary AlRu and AlRh phases probably form a continuous β-range of the CsCl-type solid solutions. The Al₉Rh₂ and C-Al₅Rh₂ dissolve up to 4.5 and 13 at.% Ru, while Al₁₃Ru₄ and Al₂Ru dissolve up to 14.5 and 8 at.% Rh, respectively. A ternary orthorhombic structure (Pbma, a = 2.34, b = 1.62 and c = 2.00 nm) related to the Al-Rh ?-phases was revealed at the extension of the Al-Rh ?-phase area at compositions up to Al₇₇Rh₁₅Ru₈.     

Analysis of the annealing kinetics of ShKh15 steel sludge waste

Conclusions In ShKh15 steel powder particles internal stresses are relieved during heating to a temperature at which they sinter to porous sponge. The processes taking place during the reduction annealing of sludges are described by an equation of chemical kinetics. The energies of activation for the sintering of filing and roll-forming sludge particles are practically identical and equal to 30 kJ/mole. ShKh15 steel sludge waste can be processed to give powder with a density ranging from 0.5 to 1.0 g/cm³.1.0% C-1.5% Cr ball-bearing grade — Publisher.Translated from Poroshkovaya Metallurgiya, No. 3(303), pp. 16–20, March, 1988.The authors are grateful to I. V. Uvara for the determination of the specific surfaces of powders.     

Physico-Chemical Investigation of Component Interactions of the Si ― Al ― O ― N ― Ti System in the Region Si3N4 ― AlN ― Al2O3 ― SiO2 ― TiN ― TiO2. Part 1. Subsystems Si3N4 ― Al2O3, Si3N4 ― TiN,and Al2O3 ― TiN

Using the methods of differential thermal and x-ray diffraction analysis an investigation was made of component reactions in the Si Al O N Ti system, particularly between the compounds Si ₃N₄ Al₂O₃, Si₃N₄ TiN, and Al₂O TiN under conditions approximating those used in the hot pressing of composites. It was established that in the reaction of Si₃N₄ with Al₂O₃, -sialon, SiO₂, AlN, and the intermediate reaction products (mullite and X-phase) are formed. In the reaction of Si₃N₄ with TiN, as a result of the decomposition of Si₃N₄ at 1650-1900°C titanium disilicide is produced, which forms eutectics with free silicon and residual TiN at 1320 and 1280°C, respectively. The reaction of Al₂O₃ with TiN similarly leads to the formation of a eutectic between Al₂O₃ and spinel at 1850°C. The presence of eutectic liquids in the specimens after sintering promotes densification of the material, and improves certain of its mechanical properties.     

A New Rhombic Approximant in the Al - Pd - Fe System

Scanning and transmission electron microscopy have been used along with x-ray diffraction in the Al - Pd - Fe system to establish a new type of B-centered rhombic N phase. The lattice constants of the N phase are as follows: a = 2.31 nm, b = 1.60 nm, and c = 4.70 nm. Electron-probe microanalysis establishes the composition: Al_76.6Pd_10.0Fe_13.4. Differential thermal analysis indicates that the N phase melts incongruently at a temperature close to 885°C. __________ Translated from Poroshkovaya Metallurgiya, Nos. 5–6(443), pp. 94–99, May–June, 2005.     

Ternary Cubic Phases in the Al – Pd Al – Fe System

Scanning and transmission electron microscopy have been used with electron-probe microanalysis, x-ray diffraction, and differential thermal analysis to examine the mutual transformations and orientation relationships between the ternary cubic C, C₁, and C₂ phases, which are considered as approximants to an icosahedral phase. By combining x-ray structure analysis with transmission electron microscopy it has proved possible to establish unambiguously the structure of the C₁ phase (Im3¯ a = 1.5389 nm). Structures are confirmed for the C phase (Pm3¯ a equals; 0.7655 nm) and the C₂ phase (Fm3¯ a = 1.5510 nm).     

Excessive Adventitial and Perivascular Vascularisation Correlates with Vascular Inflammation and Intimal Hyperplasia

Albeit multiple studies demonstrated that vasa vasorum (VV) have a crucial importance in vascular pathology, the informative markers and metrics of vascular inflammation defining the development of intimal hyperplasia (IH) have been vaguely studied. Here, we employed two rat models (balloon injury of the abdominal aorta and the same intervention optionally complemented with intravenous injections of calciprotein particles) and a clinical scenario (arterial and venous conduits for coronary artery bypass graft (CABG) surgery) to investigate the pathophysiological interconnections among VV, myeloperoxidase-positive (MPO⁺) clusters, and IH. We found that the amounts of VV and MPO⁺ clusters were strongly correlated; further, MPO⁺ clusters density was significantly associated with balloon-induced IH and increased at calciprotein particle-provoked endothelial dysfunction. Likewise, number and density of VV correlated with IH in bypass grafts for CABG surgery at the pre-intervention stage and were higher in venous conduits which more frequently suffered from IH as compared with arterial grafts. Collectively, our results underline the pathophysiological importance of excessive VV upon the vascular injury or at the exposure to cardiovascular risk factors, highlight MPO⁺ clusters as an informative marker of adventitial and perivascular inflammation, and propose another mechanistic explanation of a higher long-term patency of arterial grafts upon the CABG surgery.