University of Windsor

About: University of Windsor is a education organization based out in Windsor, Ontario, Canada. It is known for research contribution in the topics: Population & Argumentation theory. The organization has 10654 authors who have published 22307 publications receiving 435906 citations. The organization is also known as: UWindsor & Assumption University of Windsor.

High temperature tribological behavior of W containing diamond-like carbon (DLC) coating against titanium alloys

Abstract: The current study has been undertaken to determine friction, adhesion and wear mechanisms of tribological coatings for elevated temperature applications of Ti–6Al–4V alloy. Sliding wear characteristics of diamond-like carbon (DLC) coatings and polycrystalline diamond (PCD) was studied and compared with those of conventional N-based coatings, which exhibited a high coefficient of friction (COF) due to titanium adhesion to the coating surface. Hydrogenated DLC (H-DLC) and W containing DLC (W-DLC) coatings offered low and stable COF values of 0.11–012 at 25 °C while the PCD had the lowest COF of 0.05 at 25 °C. At temperatures > 200 °C H-DLC's COF increased rapidly accompanied by high coating wear. At 100 °C W-DLC had a COF of 0.06 which increased to 0.46–0.54 between 200 °C and 300 °C similar to that of H-DLC. However, at 400 °C W-DLC's COF decreased to 0.07, and a low COF of 0.08 persisted at temperatures as high as 500 °C. The governing mechanisms of the low friction of W-DLC observed at elevated temperatures were revealed by studying the compositions of the coating surfaces and the transfer layers formed on Ti–6Al–4V. Raman spectroscopy indicated that at 25 °C the transfer layers were rich in carbon, whereas at 500 °C they consisted mainly of tungsten trioxide (WO3) that formed on W-DLC's surface.

Quantification of subcellular glycogen in resting human muscle: granule size, number, and location.

Abstract: A few qualitative investigations suggested that location of muscle glycogen (G) granules in specific sites may be associated with distinct metabolic roles. Similarly, it has been suggested that the acid-soluble and -insoluble G fractions (macro- and proglycogen, respectively) are different metabolic pools and also could exist as separate entities. We employed a transmission electron microscopic technique to quantify subcellular G particle size, number, and location in human vastus lateralis biopsies of 11 resting men. The intra- and interobserver variability for the various measures was generally <4%. Granule size and number were quantified in subcellular compartments (subsarcolemmal, intra- and intermyofibrillar). Subcellular location was critical: G was more densely concentrated in the subsarcolemmal than in the myofibrillar space, whereas the single-particle volume was greater in the latter. Single-particle diameter ranged from 10 to 44 ηm and followed a continuous, normal distribution. This implies that proglycogen is not a distinct entity, but rather that pro- and macroglycogen are divisions of smaller and larger molecules. These results demonstrate a compartmentalized pattern of subcellular G deposition in human skeletal muscle for both the size and density of granules.