[Show abstract][Hide abstract] ABSTRACT: A four-ball tribological test was used to investigate the effects of a TiF3 catalyst on the tribological behaviors of biofuel soot (BS)-contaminated liquid paraffin (LP). The effects of load and rotational speed were studied as well. Scanning electron microscopy with energy-dispersive spectroscopy and X-ray photoelectron spectroscopy were conducted to investigate surface element content and chemical valence state, respectively. Results showed that the extreme pressure properties of BS-contaminated LP were all promoted with or without the presence of 0.5 wt% TiF3. The TiF3 catalyst material significantly contributed to the antiwear and the antifriction properties of LP with or without BS contamination. These results were caused by the decomposition of the TiF3 catalyst into TiO2 and fluoride (FeF2) which improved the lubricity.
Tribology International 01/2014; 77:122–131. · 1.54 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Biomass-oil soot (BS) particles were characterized by a range of analytical techniques. A comparative analysis with commercial carbon black (CB), a surrogate for diesel soot particles, was carried out. The experimental results showed that the morphologies of BS and CB particles were both spherical, with average diameters of 50 and 40 nm, respectively. There were only a few differences between the elemental composition of BS and CB. The groups (CO, OCO and COC) were presented on the surfaces of CB and BS. Moreover, it was also found that COH group was appeared on the surface of BS. BS contained more acidic and basic sites than CB, which was ascribed to the complex mixtures of biomass oil. Both BS and CB had virtually indistinguishable perturbed graphitic or turbostratic internal structures. Thus, CB can be a potential alternative to evaluate the aggregation and tribological behavior of BS in lubricating oils.
[Show abstract][Hide abstract] ABSTRACT: Export Date: 3 October 2013, Source: Scopus, CODEN: WEARA, doi: 10.1016/j.wear.2013.06.003, Language of Original Document: English, Correspondence Address: Hu, X.; Institute of Tribology, Hefei University of Technology, Hefei 230009, China; email: firstname.lastname@example.org, Funding Details: 51275143, NSFC, National Natural Science Foundation of China, References: Calabria, R., Chiariello, F., Massoli, P., Combustion fundamentals of pyrolysis oil based fuels (2007) Experimental Thermal and Fluid Science, 31, pp. 413-420;
[Show abstract][Hide abstract] ABSTRACT: Social determinants of health (SDH) are the social and physical factors that can influence unhealthy or risky behavior. Social determinants of health can affect the chances of acquiring an infectious disease - such as HIV - through behavioral influences and limited preventative and healthcare access. We analyzed the relationship between social determinants of health and HIV diagnosis rates to better understand the disparity in rates between different populations in the United States.
Using National HIV Surveillance data and American Community Survey data at the county level, we examined the relationships between social determinants of health variables (e.g., proportion of whites, income inequality) and HIV diagnosis rates (averaged for 2006-2008) among adults and adolescents from 40 states with mature name-based HIV surveillance.
Analysis of data from 1,560 counties showed a significant, positive correlation between HIV diagnosis rates and income inequality (Pearson correlation coefficient ρ = 0.40) and proportion unmarried - ages >15 (ρ = 0.52). There was a significant, negative correlation between proportion of whites and rates (ρ = -0.67). Correlations were low between racespecific social determinants of health indicators and rates.
Overall, HIV diagnosis rates increased as income inequality and the proportion unmarried increased, and rates decreased as proportion of whites increased. The data reflect the higher HIV prevalence among non-whites. Although statistical correlations were moderate, identifying and understanding these social determinants of health variables can help target prevention efforts to aid in reducing HIV diagnosis rates. Future analyses need to determine whether the higher proportion of singles reflects higher populations of gay and bisexual men.