Impact of residual elements on zinc quality in the production of zinc oxide

The paper is focused on zinc oxide manufacturing process. The present work deals with the character and morphology of the input material for the production of ZnO by the indirect pyrometallurgical process. Undesirable phases in the feedstock can be identified through profound recognition of the source material and the nature of its microstructure. If these compounds diffuse into the lining during thermal processes, they become the cause of stress in metallurgical ceramics. The emergence of these chemical reactions may subsequently affect the entire metallurgical zinc smelting process. The results obtained by analysis are used to minimize waste - zinc slag and to eliminate the conditions which enable the formation of the undesired product, thereby increasing the productivity of the ZnO production

Mechanisms of plastic deformation and fracture in coarse grained Fe–10Al–4Cr–4Y2O3 ODS nanocomposite at 20–1300°C

The coarse-grained Fe–10Al–4Cr–4Y2O3ODS nanocomposite (denoted as FeAlOY) has been developed by the authors and shows promising potential for high-temperature structural applications at 1000–1300 °C. Compared to classical ODS alloys, the FeAlOY contains ten times higher volume fraction of the stable Y2O3 nanodispersion, which gives the alloy its high-temperature strength. Furthermore, the high content of Al in the matrix guarantees excellent oxidation resistance. In practice, one can expect that the FeAlOY is loaded in the temperature range of 20–1300 °C due to intermittent device operation. To ensure a safe operation, it is necessary to determine the tensile strength and ductility of the FeAlOY in the whole temperature range and detect the dominant mechanisms of strengthening, plastic deformation, and fracture in the characteristic temperature ranges. Above 1100 °C the FeAlOY reaches ultimate tensile strength of ∼ 100 MPa and plasticity of ∼ 1%. However, in the temperature range of 400–600 °C, the plasticity can climb above 40%. The achieved results can also be utilized for the design of the FeAlOY pieces shaping by hot pressing

Metal-containing landfills as a source of antibiotic tolerance

To unveil the potential effect of metal presence to antibiotic tolerance proliferation, four sites of surface landfills containing tailings from metal processing in Slovakia (Hnusta, Hodrusa, Kosice) and Poland (Tarnowskie Gory) were investigated. Tolerance and multitolerance to selected metals (Cu, Ni, Pb, Fe, Zn, Cd) and antibiotics (ampicillin, tetracycline, chloramphenicol, and kanamycin) and interrelationships between them were evaluated. A low bacterial diversity (Shannon-Wiener index from 0.83 to 2.263) was detected in all sampling sites. Gram-positive bacteria, mostly belonging to the phylum Actinobacteria, dominated in three of the four sampling sites. The recorded percentages of tolerant bacterial isolates varied considerably for antibiotics and metals from 0 to 57% and 0.8 to 47%, respectively, among the sampling sites. Tolerances to chloramphenicol (45-57%) and kanamycin (32-45%) were found in three sites. Multitolerance to several metals and antibiotics in the range of 24 to 48% was recorded for three sites. A significant positive correlation (p < 0.05) for the co-occurrence of tolerance to each studied metal and at least one of the antibiotics was observed. Exposure time to the metal (landfill duration) was an important factor for the development of metal-as well as antibiotic-tolerant isolates. The results show that metal-contaminated sites represent a significant threat for human health not only for their toxic effects but also for their pressure to antibiotic tolerance spread in the environment.Web of Science1952art. no. 26