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...

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...

Research into the usage of locally available construction material is essential and beneficial in ensuring a cost-effective project. One natural resources that be used as supplementary cementitious metakaolin. This research aims to investigate performance mortar reinforced with micro- ultrafine metakaolin based on compressive strength water absorption tests. Locally sourced was mixed cement aft...

As a metamorphic product of coal, microcrystalline graphite is ultrafine polycrystalline structure with near-isotropic and highly graphitized characteristics, which endows itself great potential as filler for ultrafine-grain isotropic (UGIG). In this work, two kinds based UGIG, MGG12 MGG8, are prepared by liquid mixing process from an average particle size 12 8 ?m, respectively. For comparison,...

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...