Atom probe tomography (APT) is commonly used to study solute clustering and precipitation in materials. However, standard techniques used to identify and characterize clusters within atom probe data, such as the density-based spatial clustering applications with noise (DBSCAN), often underperform with respect to small clusters. This is a limitation of density-based cluster identification algorithms, due to their dependence on the parameter Nmin, an arbitrary lower limit placed on detectable cluster sizes.
View Article and Find Full Text PDFMetall Mater Trans A Phys Metall Mater Sci
June 2023
The current work presents a systematic study of two alloy compositions (RR3010 and CMSX-4) and two types of coatings: inward grown (pack) and outward grown (vapour) deposited aluminides, exposed to 98NaSO-2NaCl mixture. Grit blasting was used on some of the samples, prior to coating, to mimic in-service procedures and remove oxides from the surface prior to coating. Two-point bend tests were then performed on the coated samples, with and without applied salt at 550 °C for 100 hours.
View Article and Find Full Text PDFThe functional properties of the high-temperature superconductor Y1Ba2Cu3O7-δ (Y-123) are closely correlated to the exact stoichiometry and oxygen content. Exceeding the critical value of 1 oxygen vacancy for every five unit cells (δ>0.2, which translates to a 1.
View Article and Find Full Text PDFThe vacancy ordering behavior of an A-site deficient perovskite system, CaLaTiO, was studied using atomic resolution scanning transmission electron microscopy (STEM) in conjunction with electron energy-loss spectroscopy (EELS), with the aim of determining the role of A-site composition changes. At low La content (x = 0.2), adopting Pbnm symmetry, there was no indication of long-range ordering.
View Article and Find Full Text PDFStereospecific serum assays of the non-steroidal antiinflammatory drug flunoxaprofen (S(+)-2-(4-fluorophenyl)-a-methyl-5-benzoxazoleacetic acid, Priaxim) were performed in rats after the oral administration of 10 mg/kg b.w. of the different enantiomeric forms of the drug or of the racemate in order to establish the occurrence and the rate of biotransformation of R(-)-flunoxaprofen to the S(+)-enantiomer, which is the pharmacologically active form.
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