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Fine particles (PM 2.5 ) were collected and analyzed from April 2010 through January 2011 in Chungju to investigate the characteristics of PM 2.5 and its ionic species. The annual mean concentrations of PM 2.5 , SO 4 2-, NO 3 -, and NH 4 + + in the particulate phase were 40.84, 7.61, 7.14 and 3.74 μg/m 3 , respectively. PM 2.5 concentrations were higher in fall and spring than in winter and summer. The elevated concentrations episodes are the main factor that enhanced the PM 2.5 concentrations in the fall. Among the major ionic species SO 4 2-showed the highest concentration, followed by NO 3 -and NH 4 + + , NO 3 -exhibited higher concentrations during the winter, but SO 4 2-and NH 4 + + were not showed seasonal variation. The high correlations were found among PM 2.5 , SO 4 2-, NO 3 -and NH 4 + + during all seasons except for spring. The evaluation of backward trajectories and meteorological records show that the highest PM 2.5 concentration levels occurred during W-NW weather conditions, which influenced by the emission sources of China area. The low pollution levels generally occurred during E-S weather conditions, which influenced by the East Sea and south of the Yellow Sea. The elevated PM 2.5 mass concentrations arouse the concentration of NO 3 -, but no effects on SO 4 2-and NH 4 + + .

Green tea waste (GTW) is a naturally abundant material, and it has not been widely reused into more valuable materials. The composition of GTW was identified using NMR for carbohydrate composition, an element analyzer for protein content, acetone and hot water extraction for evaluating extractives, and Klason lignin for lignin content. GTW can be converted into nanoparticles by carboxymethylation as pretreatment of the degree of substitutions (DS) and high-pressure homogenizer for nanoparticle making. GTW was prepared using various DS 0 until DS 0.4. The results showed that GTW DS has a more than −30 mV zeta potential, suitable for stable nanoemulsion formulations. The particle size of GTW DS decreases with increasing carboxyl content in the hydrogel, which has a width and length from GTW DS 0.3 to DS 0.4. As a humectant, the water retention value (WRV) of GTW with various DS was increased; DS 0.3 is the best. DS 0.4 has the highest viscosity, storage, and loss modulus as rheology modifiers.

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