Microstructures in nature are ultrafine and ordered in biological roles, which have attracted material scientists. Spirulina forms three-dimensional helical microstructure, one of remarkable features in nature beyond our current processing technology such as lithography in terms of mass-productivity and structural multiplicity. Spirulina varies its diameter, helical pitch, and/or length against...

Klein LW, Stewart JC, Oberdorster G, Frampton MW. Ultrafine particles activate platelets in vitro. American Journal of Respiratory and Critical Care Medicine 2007;175:A169. not available Abstract Shah AP, Stewart JC, Klein LW, Utell MJ, Frampton MW. Effects of carbon ultrafine particles on platelet activation. Proceedings of the American Thoracic Society 2006;3:A551. not availableShah AP, Stewa...

Intrinsically water-stable electrospun threedimensional ultrafine fibrous soy protein scaffolds for soft tissue engineering using adipose derived mesenchymal stem cells" (2014). Faculty Publications-Textiles, Merchandising and Fashion Design. Paper 35. Soy protein, the plant protein from soybean, was electrospun into intrinsically water-stable scaffolds with large volume and ultrafine fibers or...

For high-strength titanium VT1-0, the ultrafine-grained structure of which was obtained by mechanical-thermal treatment using methods helical and longitudinal rolling followed annealing to relieve stress first kind. The effect long-term loading in creep mode at elevated temperature on size shape grains has been studied. A similar study previously carried out for recrystallized coarse-grained tr...

Equal channel angular pressing results in ultrafine-grained (approximately 200-500 nm) Ti with superior mechanical properties without harmful alloying elements, which benefits medical implants. To further improve the bioactivity of Ti surfaces, Ca/P-containing porous titania coatings were prepared on ultrafine-grained and coarse-grained Ti by micro-arc oxidation (MAO). The phase identification,...

This paper aims at investigating the influence of partial replacement of Portland cement with ultrafine fillers compared to limestone powder on the durability and mechanical characteristics of concrete. For this purpose, ultrafine calcium carbonate materials with different specific surface areas of 9.7 and 15.1 m2/g and limestone powder (0.72 m2/g) were used. The results indicate that the ultra...

New particle formation and growth events have been observed in several urban areas and are of concern due to their potential negative effects on human health. The main purpose of this study was to investigate the chemistry of ultrafine particles during the growth phase of the frequently observed nucleation events in Pittsburgh (approximately 100 events per year) and therefore infer the mechanis...

Dosimetry parameters such as deposition, clearance, retention, and translocation and dissolution of inhaled particles in and to different lung compartments may be important for the persistence of particles in the lung and may correlate with adverse pulmonary effects. We investigated such correlations using a model involving TiO2 particles of two particle sizes (20 nm diameter, ultrafine; 250 nm...

BACKGROUND Epidemiologic studies show that exposure to particulate air pollution is associated with asthma exacerbation. Ultrafine particles (diameter <100 nm) may contribute to these adverse effects. OBJECTIVE To investigate potential adjuvant activity of inhaled elemental carbon ultrafine particles (EC-UFPs) on allergic airway inflammation. METHODS The effects of ultrafine particle inhala...

This article describes work performed on the assessment of the levels of airborne ultrafine particles emitted in two welding processes metal-active gas (MAG) of carbon steel and friction-stir welding (FSW) of aluminium in terms of deposited area in alveolar tract of the lung using a nanoparticle surface area monitor analyser. The obtained results showed the dependence from process parameters on...