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Sorption data of Cd-TZ for C2H2, C2H4, and CO2

In the contemporary electric arc furnace (EAF) steelmaking industry, increasing contents and temperature homogenization via fluid flow stirring is found to be an effective method of improving production quality and smelting efficiency. It is a trend for different factories with bowl-shaped furnaces to apply the bath fluidity enhancement technology. EAF has plenty of advantages in modern steelmaking industry, and the improvements on the EAF steelmaking process have come up with two major tasks, namely reduction in energy consumption and tap-to-tap time. The latter task requires an essential understanding of every phase in EAF steelmaking process. The flat bath phase with poor bath fluid flow was crucial to the product quality and metallurgical efficiency considering EAF’s bowl-shaped structure. The research of three stirring bath methods, oxygen jets injection, electromagnetic stirring, and bottom blowing, were introduced, and then the detailed parameters of each method with their influences on molten bath fluidity were presented.

BackgroundAtrial fibrillation (AF) is the most common sustained cardiac arrhythmia and engenders significant global health care burden. The underlying mechanisms of AF is remained to be revealed and current treatment options for AF have limitations. Besides, a detection system can help identify those at risk of developing AF and will enable personalized management.Materials and MethodsIn this study, we utilized the robust rank aggregation method to integrate six AF microarray datasets from the Gene Expression Omnibus database, and identified a set of differentially expressed genes between patients with AF and controls. Potential compounds were identified by mining the Connectivity Map database. Functional modules and closely-interacted clusters were identified using weighted gene co-expression network analysis and protein–protein interaction network, respectively. The overlapped hub genes were further filtered. Subsequent analyses were performed to analyze the function, biological features, and regulatory networks. Moreover, a reliable Machine Learning-based diagnostic model was constructed and visualized to clarify the diagnostic features of these genes.ResultsA total of 156 upregulated and 34 downregulated genes were identified, some of which had not been previously investigated. We showed that mitogen-activated protein kinase and epidermal growth factor receptor inhibitors were likely to mitigate AF based on Connectivity Map analysis. Four genes, including CXCL12, LTBP1, LOXL1, and IGFBP3, were identified as hub genes. CXCL12 was shown to play an important role in regulation of local inflammatory response and immune cell infiltration. Regulation of CXCL12 expression in AF was analyzed by constructing a transcription factor-miRNA-mRNA network. The Machine Learning-based diagnostic model generated in this study showed good efficacy and reliability.ConclusionKey genes involving in the pathogenesis of AF and potential therapeutic compounds for AF were identified. The biological features of CXCL12 in AF were investigated using integrative bioinformatics tools. The results suggested that CXCL12 might be a biomarker that could be used for distinguishing subsets of AF, and indicated that CXCL12 might be an important intermediate in the development of AF. A reliable Machine Learning-based diagnostic model was constructed. Our work improved understanding of the mechanisms of AF predisposition and progression, and identified potential therapeutic avenues for treatment of AF.

R31 filter aid containing macromolecular long-chain organic compounds with carboxyl, sulfonic, amide groups was used to improve the filtration of fine hematite concentrate in this study. The carboxyl, sulfonic and amide groups adsorbed on the surface of hematite concentrate particles. The macromolecular long-chain organic compounds flocculated fine hematite concentrate particles to increase the apparent particles size. The H+ ions ionized by carboxylic acid and sulfonic groups compressed hydration film of hematite concentrate particles. The hydrophobic groups in the organic matter decreased the surface wettability of fine hematite concentrate particles. Thinner hydration film and less wettability decreased the water adhesion on surface of hematite concentrate particles. The dehydration rate of filter cake increased from 1.82 × 10−3 ml∙cm2∙s−1 to 3.20 × 10−3 ml∙cm2∙s−1 with a 75.82% increase, when the mass concentration of R31 filter aid increased from 0 to 1800 g/t, and the filter cake moisture content decreased from 19.88% to 17.72%.

The effects of titanium slag on the roasting and metallurgical properties of fluorine-bearing iron concentrate pellets were experimentally investigated in this study. Results show that the compression strength of fluorine-bearing iron concentrate pellets improved up to 3700 Newton/Pellet and the suitable range of roasting temperatures expanded 150 °C with the addition of titanium slag. The results of the scanning electron microscope and energy dispersive spectrum showed that the main phases of fluorine-bearing iron concentrate pellet with titanium slag were hematite, rutile, Fe2TiO5 and silicates. Moreover, the metallurgical properties of roasted fluorine-bearing iron concentrate pellets were improved by adding titanium slag. The softening range of roasted fluorine-bearing concentrate pellets decreased from 106 °C to 59 °C. The reduction swelling index of the roasted fluorine-bearing iron concentrate pellets decreased from 22.76% to 14.26% with the addition of titanium slag.

The technology of coherent lime powder injection (C-LPI) was developed and applied in the electric arc furnace steelmaking, which can inject lime powder into the molten pool deeply and effectively....

The effects of corrosion temperature, oxygen flow rate and corrosion time on the transformation of metallic iron were systematically studied, and the effects of mineral phases of Fe-bearing products on Ti–Fe separation were investigated. The reaction mechanism of metallic iron in corrosion process was proposed. The results showed that corrosion temperature played a key role in determining the transformation of metallic iron in reduced ilmenite during corrosion process. Under suitable corrosion conditions, Fe-bearing mineral in reduced ilmenite could be converted to amorphous ferric hydroxide, lepidocrocite, hematite and magnetite, respectively, and lepidocrocite was the most easily separated Fe-bearing mineral from corrosion products owing to the significant density difference between lepidocrocite and Ti-rich materials. The Ti-rich material with 77.81 wt.% TiO2 and Fe-bearing product with 52.69 wt.% total Fe were obtained by gravity separation. The Ti recovery ratio and Fe recovery ratio were 91.16% and 86.27%, respectively.

The method of carbon powder mixed injection with a shrouding supersonic oxygen jet was proposed to increase the utilization efficiency of carbon powder and improve the foaming slag operation during the electric arc furnace (EAF) steelmaking process by delivering the carbon powder more deeply into the molten bath. In this study, the fluid flow characteristics of the carbon powder mixed injection with a shrouding supersonic oxygen jet were studied and analyzed using numerical simulations, which were first validated by a cold test experiment. Compared with the conventional carbon powder injection without a shrouding jet, the shrouding supersonic oxygen jet can protect the central gas-powder jet against the entrainment of the surrounding atmosphere, increase the velocity of carbon powder and make the carbon powder cluster together in a longer distance. Furthermore, the industrial application research was carried out in a 50-ton commercial Consteel EAF, and the relative metallurgical effects were also studied. Compared with EAF steelmaking using conventional carbon powder injection without a shrouding jet, the powder consumption, tap-to-tap time, FeO content in the final molten slag and phosphorus content of the final molten steel were reduced by 19.3 kWh/ton, 4 min/heat, 2.6 pct and 1.2 × 10−3 pct, respectively, after using the method of carbon powder mixed injection with a shrouding supersonic oxygen jet.

The effects of CaO content, MgO content and smelting temperature on the vanadium behavior during the smelting of vanadium titanomagnetite metallized pellets were investigated. The thermodynamics of reduction and distribution of vanadium was analyzed and the high-temperature smelting experiments were carried out. The thermodynamic calculations show that the distribution ratio of vanadium between the slag and the hot metal decreases with the increments of CaO and MgO content in the slag as well as the increase of the smelting temperature. The smelting experiments demonstrate that the vanadium content in iron and the recovery rate of vanadium in pig iron increase as the CaO content, MgO content and smelting temperature increase, whereas the vanadium distribution ratio between the slag and iron tends to decrease. Moreover, the recovery rate of vanadium in pig iron has a rising trend with increasing the optical basicity of the slag. The addition of MgO in the slag to increase the slag optical basicity can not only improve the vanadium reduction but also promote the formation of magnesium-containing anosovite, which is beneficial to following titanium extraction.