C–O–H2 ternary diagram for evaluation of carbon activity in CH4-containing gas mixtures

The C–O–H2 ternary diagram is presented to characterize the carbon activity in equilibrium with gas mixtures containing CH4, CO, CO2, H2O, and H2 at different temperatures and pressures. The three reactions for carbon deposition from CH4, CO, and CO + H2 are considered jointly, and the combined equilibrium carbon activity is calculated. The lines on the diagram show a set of gas compositions that is in equilibrium with a defined value of carbon activity at a given temperature and pressure. It was possible to verify that carbon activity in equilibrium with the direct reduction process gas of Midrex is 0.15 and of Energiron ZR is 8.5, explaining the higher carbon content in the reduced iron for the latter. In the case of steam reforming of methane and methanol, carbon activity in usual industrial conditions are of 0.35 and 0.73 respectively. Finally steam reforming of ethanol was evaluated and it was shown that carbon deposition is expected at 240 °C but would be avoided at temperatures of 500 °C and higher in equilibrium conditions. The proposed diagram could be useful in many chemical, catalytic, and metallurgical processes for study or prevention of carbon formation

C–O–H2 ternary diagram for evaluation of carbon activity in CH4-containing gas mixtures

The C–O–H2 ternary diagram is presented to characterize the carbon activity in equilibrium with gas mixtures containing CH4, CO, CO2, H2O, and H2 at different temperatures and pressures. The three reactions for carbon deposition from CH4, CO, and CO + H2 are considered jointly, and the combined equilibrium carbon activity is calculated. The lines on the diagram show a set of gas compositions that is in equilibrium with a defined value of carbon activity at a given temperature and pressure. It was possible to verify that carbon activity in equilibrium with the direct reduction process gas of Midrex is 0.15 and of Energiron ZR is 8.5, explaining the higher carbon content in the reduced iron for the latter. In the case of steam reforming of methane and methanol, carbon activity in usual industrial conditions are of 0.35 and 0.73 respectively. Finally steam reforming of ethanol was evaluated and it was shown that carbon deposition is expected at 240 °C but would be avoided at temperatures of 500 °C and higher in equilibrium conditions. The proposed diagram could be useful in many chemical, catalytic, and metallurgical processes for study or prevention of carbon formation.publishedVersio

C–O–H2 ternary diagram for evaluation of carbon activity in CH4-containing gas mixtures

The C–O–H2 ternary diagram is presented to characterize the carbon activity in equilibrium with gas mixtures containing CH4, CO, CO2, H2O, and H2 at different temperatures and pressures. The three reactions for carbon deposition from CH4, CO, and CO + H2 are considered jointly, and the combined equilibrium carbon activity is calculated. The lines on the diagram show a set of gas compositions that is in equilibrium with a defined value of carbon activity at a given temperature and pressure. It was possible to verify that carbon activity in equilibrium with the direct reduction process gas of Midrex is 0.15 and of Energiron ZR is 8.5, explaining the higher carbon content in the reduced iron for the latter. In the case of steam reforming of methane and methanol, carbon activity in usual industrial conditions are of 0.35 and 0.73 respectively. Finally steam reforming of ethanol was evaluated and it was shown that carbon deposition is expected at 240 °C but would be avoided at temperatures of 500 °C and higher in equilibrium conditions. The proposed diagram could be useful in many chemical, catalytic, and metallurgical processes for study or prevention of carbon formation

C–O–H2 ternary diagram for evaluation of carbon activity in CH4-containing gas mixtures

The C–O–H2 ternary diagram is presented to characterize the carbon activity in equilibrium with gas mixtures containing CH4, CO, CO2, H2O, and H2 at different temperatures and pressures. The three reactions for carbon deposition from CH4, CO, and CO + H2 are considered jointly, and the combined equilibrium carbon activity is calculated. The lines on the diagram show a set of gas compositions that is in equilibrium with a defined value of carbon activity at a given temperature and pressure. It was possible to verify that carbon activity in equilibrium with the direct reduction process gas of Midrex is 0.15 and of Energiron ZR is 8.5, explaining the higher carbon content in the reduced iron for the latter. In the case of steam reforming of methane and methanol, carbon activity in usual industrial conditions are of 0.35 and 0.73 respectively. Finally steam reforming of ethanol was evaluated and it was shown that carbon deposition is expected at 240 °C but would be avoided at temperatures of 500 °C and higher in equilibrium conditions. The proposed diagram could be useful in many chemical, catalytic, and metallurgical processes for study or prevention of carbon formation

Liraglutide and Renal Outcomes in Type 2 Diabetes.

BACKGROUND: In a randomized, controlled trial that compared liraglutide, a glucagon-like peptide 1 analogue, with placebo in patients with type 2 diabetes and high cardiovascular risk who were receiving usual care, we found that liraglutide resulted in lower risks of the primary end point (nonfatal myocardial infarction, nonfatal stroke, or death from cardiovascular causes) and death. However, the long-term effects of liraglutide on renal outcomes in patients with type 2 diabetes are unknown. METHODS: We report the prespecified secondary renal outcomes of that randomized, controlled trial in which patients were assigned to receive liraglutide or placebo. The secondary renal outcome was a composite of new-onset persistent macroalbuminuria, persistent doubling of the serum creatinine level, end-stage renal disease, or death due to renal disease. The risk of renal outcomes was determined with the use of time-to-event analyses with an intention-to-treat approach. Changes in the estimated glomerular filtration rate and albuminuria were also analyzed. RESULTS: A total of 9340 patients underwent randomization, and the median follow-up of the patients was 3.84 years. The renal outcome occurred in fewer participants in the liraglutide group than in the placebo group (268 of 4668 patients vs. 337 of 4672; hazard ratio, 0.78; 95% confidence interval [CI], 0.67 to 0.92; P=0.003). This result was driven primarily by the new onset of persistent macroalbuminuria, which occurred in fewer participants in the liraglutide group than in the placebo group (161 vs. 215 patients; hazard ratio, 0.74; 95% CI, 0.60 to 0.91; P=0.004). The rates of renal adverse events were similar in the liraglutide group and the placebo group (15.1 events and 16.5 events per 1000 patient-years), including the rate of acute kidney injury (7.1 and 6.2 events per 1000 patient-years, respectively). CONCLUSIONS: This prespecified secondary analysis shows that, when added to usual care, liraglutide resulted in lower rates of the development and progression of diabetic kidney disease than placebo. (Funded by Novo Nordisk and the National Institutes of Health; LEADER ClinicalTrials.gov number, NCT01179048 .)

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved