The aim of this study is to assess the levels of airborne ultrafine particles emitted in welding processes (tungsten inert gas [TIG], metal active gas [MAG] of carbon steel, and friction stir welding [FSW] of aluminum) in terms of deposited area in pulmonary alveolar tract using a nanoparticle surface area monitor (NSAM) analyzer. The obtained results showed the dependence of process parameters...

This paper provides a new account for why online processing of filler-gap relative clause dependencies is more difficult in cases where filler-gap interacts with object control than in cases involving subject control, as reported by Frazier et al. (1983). Frazier et al. (1983) argued for a Recent Filler heuristic in which the parser expects to discharge the most recent filler at every gap site....

Materials with ultrafine grain sizes are attractive for use in micro-forming operations. High-pressure torsion (HPT) is an effective technique that allows disc materials subjected to torsional deformation to generate microstructures with significant grain refinement. Generally, ultrafine-grained materials exhibit high strength but their ductility is limited because they have both a low rate of ...

Polymer based nanocomposites, in which inorganic nanoparticles are dispersed in organic polymer matrices, have attracted materials scientists’ attention owing to their unique properties, resulting from their nano-scale microstructure. Because of their large surface area, nanoparticles interact with the polymer matrix and carry a load effectively. The mechanical properties of these composites ca...

Powder-liquid type metal-resin composites, using Ag-Sn irregular particles as the filler, 4-META as coupling agent and UDMA + TEGDMA as resin matrix, were experimentally prepared under 9 different conditions (three different particle sizes and three different filler contents). The flexural strength and flexural modulus were measured. Three different irregular particle size MRCs without redox-in...

in this study, precipitated calcium carbonate (pcc) was modified using cationic starch, and its effect on optical and physical properties of paper was examined in comparison with unmodified filler afterwards. to determine the filler retention in paper, both modified and unmodified fillers were added to pulp suspensions by 20, 30, and 40 percentages. for comparing the utilization effect of modif...

Air pollution is associated with significant adverse health effects, including increased cardiovascular morbidity and mortality. Exposure to particulate matter with an aerodynamic diameter of <2.5 microm (PM(2.5)) increases ischemic cardiovascular events and promotes atherosclerosis. Moreover, there is increasing evidence that the smallest pollutant particles pose the greatest danger because of...

The aim of this study was to contribute to the assessment of exposure levels of ultrafine particles in the urban environment of Lisbon, Portugal, due to automobile traffic, by monitoring lung deposited alveolar surface area (resulting from exposure to ultrafine particles) in a major avenue leading to the town center during late spring, as well as in indoor buildings facing it. Data revealed dif...

A Ti–46Al(at.%) polysynthetically twinned alloy, which contained a characteristic lamellar spacing of k 1⁄4 1:3 lm, was converted to a polycrystalline fully-lamellar microstructure with k 1⁄4 19:9 nm using an a-phase solution treatment followed by a2 þ c aging. Tensile experiments, performed on microsamples extracted from within single grains of the polycrystalline material, illustrated that ul...

The quality of the refractories applied on integrated gasification combined cycle should be a key factor that affects both the reliability and the economics of gasifier operation. To enhance the workability of chromia/alumina castables, three types of ultrafine alumina powder were added to improve the workability. Densification behavior of such castables in the presence of ultrafine alumina was...