ABSTRACT
The synergistic effect of different types of solid particles in liquid lubricants is of great interest. In this work, g-C3N4 nanosheets were initially prepared using a calcination method and then as-prepared, and h-BN were used as lubricating additives to the white oil. A comparison between the mixed additives and the single g-C3N4 or h-BN additives revealed that the base oil with the addition of g-C3N4 and h-BN showed the best lubricating properties. The results show a 12.3% reduction in friction coefficient, resulting in a 68.6% reduction in wear rate compared to the white oil when filled with 0.5 wt% g-C3N4 and h-BN (1:1 by weight). Moreover, the addition of g-C3N4 and h-BN improves the high-temperature lubrication properties of the white oil. However, the friction coefficient and wear rate increase with increasing oil temperature. The large contact area between g-C3N4 and its sliding counterpart and the strong adhesive force between h-BN and its sliding counterpart improve the film formation efficiency, leading to enhanced tribological properties under oil lubrication conditions.
ABSTRACT
BACKGROUND: Cytokine polymorphismsmight influence the predisposition to diabetic nephropathy (DN), but the results of already published related studies are still controversial and ambiguous. OBJECTIVES: The authors designed this meta-analysis to more precisely estimate relationships between TNF-α/IL-1/IL-4/IL-8/IL-18polymorphisms and DN by pooling the results of already published related studies. METHODS: The authors searched Pubmed, Embase, Web of Science and CNKI for already published studies. Thirty already published studies were pooled and analyzed in this meta-analysis. RESULTS: The overall pooled meta-analysis results showed that distributions of TNF-α -238 G/A, TNF-α -308 G/A, TNF-α -1031 C/T, IL-1A -889 C/T, IL-1B -511 C/Tand IL-18 -137 G/C polymorphisms among patients and controls differed significantly. Additionally, we also found that distributions of TNF-α -308 G/A, IL-1B -511 C/T and IL-18 -137 G/C polymorphisms among patients and controls from Asians differed significantly, and the distribution of the IL-1B -511 C/T polymorphism among patients and controls from Caucasians also differed significantly. CONCLUSION: The meta-analysis results demonstrated that TNF-α -238 G/A, TNF-α -308 G/A, TNF-α -1031 C/T, IL-1A -889 C/T, IL-1B -511 C/Tand IL-18 -137 G/Cpolymorphisms might influence predisposition to DN in the overall pooled population. Moreover, TNF-α -308 G/A, IL-1B -511 C/T and IL-18 -137 G/C polymorphisms might influence predisposition to DN in Asians, whereas the IL-1B -511 C/T polymorphism might also influence predisposition to DN in Caucasians.
