BACKGROUND Ultrafine particles have been hypothesised to be an important contributing factor in the toxicity and adverse health effects of particulate air pollution (PM10) and nanoparticles are used increasingly in industrial processes. AIMS To compare the ability of ultrafine and fine particles of titanium dioxide and carbon black to induce inflammation, cause epithelial injury, and affect t...

In this research, we assessed the influence of an ultrafine 2CaO·SiO₂ powder on the hydration properties of a reactive powder concrete system. The ultrafine powder was manufactured through chemical combustion method. The morphology of ultrafine powder and the development of hydration products in the cement paste prepared with ultrafine powder were investigated by scanning electron microscopy (S...

Ultrafine composite fibers consisting of a thermoplastic polyurethane solid-solid phase-change material and organic lanthanide luminescent materials were prepared through a parallel electrospinning technique as an innovative type of ultrafine, dual-functional fibers containing phase-change and luminescent properties. The morphology and structure, thermal energy storage, and luminescent properti...

Research regarding the magnitude of ultrafine particle levels at highway toll stations is limited. This study measured ambient concentrations of ultrafine particles at a highway toll station from October 30 to November 1 and November 5 to November 6, 2008. A scanning mobility particle sizer was used to measure ultrafine particle concentrations at a ticket/cash tollbooth. Levels of hourly averag...

Cell disruption is an important step during the extraction of C-phycocyanin from Spirulina platensis. An ultrafine shearing method is introduced and combined with soaking and ultrasonication to disrupt the cell walls of S. platensis efficiently and economically. Five kinds of cell disruption method, including soaking, ultrasonication, freezing-thawing, soaking-ultrafine shearing and soaking-ult...

Motor vehicles in urban areas are the main source of ultrafine particles (diameters < 0.1 μm). Ultrafine particles are generally measured in terms of particle number because they have little mass and are prolific in terms of their numbers. These sized particles are of particular interest because of their ability to enter deep into the human respiratory system and contribute to negative health e...

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...

ABSRACT A comparative study of the surface microstructural changes after fatigue in an ultrafine grained and coarse grained aluminum alloy was performed using orientation imaging microscopy (OIM). The fraction of low angle boundaries with misorientation less than 2.5 ̊ increased for both the coarse and ultrafine grained alloys. A consistent decrease in the fraction of low angle boundaries, with ...