Data for: Experimental study of the phase relationships in the SiO2-SrO-Al2O3 system

The liquidus lines in the silica rich area of the ternary SiO2-SrO-Al2O3 phase diagram were determined experimentally at 1723 K (1450°C), 1823 K (1550°C), and 1873K (1600°C) using the quenching technique. Quenched samples were analyzed using LOM, SEM and XRD. Based on the obtained results, the liquidus lines were constructed at the three temperatures. The sample compositions studied, the equilibrating temperature and the phases present are listed in this dataset.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Viscosity measurements on some fayalite slags

In the present study, viscosity measurements on Fe-O-Si slags have been carried out using rotating cylinder method. The slag samples for viscosity measurement were prepared by pre-melting appropriate stoichiometric amounts of Fe, Fe2O3 and SiO2 in an iron crucible under argon atmosphere, which ensured that Fe ions in the slag were predominantly in the valence state of +2. The viscosities of the pre-melted slag samples were measured in iron as well as nickel crucibles under argon atmosphere at different temperatures. The measured viscosity values obtained in the two kinds of crucibles were found to be in good agreement, indicating thereby that nickel crucibles can be successfully used for viscosity measurements. In order to investigate the effect of oxidation of Fe2+ to Fe3+, the binary FenO-SiO2 slag was kept in a nickel crucible under oxidising conditions using a CO/CO2 atmosphere and viscosity measurements were carried out dynamically as a function of time at 1 623 and 1 673 K. With time, Fe3+ concentration in the slag increased and hence the viscosity changed progressively. The rate controlling step for the oxidation reaction was considered to be the mass transfer of CO, in the gas stream to the slag-gas interface. A simple kinetic analysis was used to predict the concentration of Fe3+ in the slag with time, The measured viscosity with time indicated that the viscosity remains almost the same during initial period of oxidation. The viscosity raises sharply when the Fe3+ concentration in the slag, calculated as Fe2O3 reached around 7 mass%

Mathematical model to simulate the temperature and composition distribution inside the flux layer of a continuous casting mould

A model is presented to predict the mass transport and heat transfer in a continuous casting mould flux bed. Physically consistent micromodels for carbon burning, evaporation of volatiles and thermophysical properties in the mould flux layer have been combined with a one-dimensional finite-difference model of the continuous casting mould flux bed. The sensitivity of the model to bed height, flux consumption rate, carbon burning and powder particle size is investigated for a mould flux composition corresponding to an industrial casting powder

Study of the deoxidation of steel with aluminum wire injection in a gas-stirred ladle

In the present work, the deoxidation of liquid steel with aluminum wire injection in a gas-stirred ladle was studied by mathematical modeling using a computational fluid dynamics (CFD) approach. This was complemented by an industrial trial study conducted at Uddeholm Tooling AB (Hagfors, Sweden). The results of the industrial trials were found to be in accordance with the results of the model calculation. In order to study the aspect of nucleation of alumina, emphasis was given to the initial period of deoxidation, when aluminum wire was injected into the bath. The concentration distributions of aluminum and oxygen were calculated both by considering and not considering the chemical reaction. Both calculations revealed that the driving force for the nucleation of Al2O3 was very high in the region near the upper surface of the bath and close to the wire injection. The estimated nucleation rate in the vicinity of the aluminum wire injection point was much higher than the recommended value for spontaneously homogeneous nucleation, 10(3) nuclei/(cm(3)/s). The results of the model calculation also showed that the alumina nuclei generated at the vicinity of the wire injection point are transported to other regions by the flow

Fungal Melanin and the Mammalian Immune System

Melanins are ubiquitous complex polymers that are commonly known in humans to cause pigmentation of our skin. Melanins are also present in bacteria, fungi, and helminths. In this review, we will describe the diverse interactions of fungal melanin with the mammalian immune system. We will particularly focus on Cryptococcus neoformans and also discuss other major melanotic pathogenic fungi. Melanin interacts with the immune system through diverse pathways, reducing the effectiveness of phagocytic cells, binding effector molecules and antifungals, and modifying complement and antibody responses