The chemical composition of the continental crust play an important role in understanding of crustal formation and evolution and quantifying other processes taking place within continental crust. We summarized geochemical data reported in the previous literature for the crustal rocks in the Korean Peninsula and divided their chemical composition into geologic time scale. In the variation diagram normalized by average composition of the upper crustal rocks, the geochemical characteristics of the upper crust during Triassic period is different from those of the upper crustal rocks after Jurassic period or before Precambrian. However, the geochemical characteristics of the Jurassic and Precambrain period are similar each other. Our summarized data indicate that the source material of Triassic upper crust may be different from that of Jurassic or Precambrian upper crust.

This experiment was conducted to find out the effects of nitrous oxide (N 2 O) on the postharvest quality of 'Janghowon hwangdo' peach fruits. Fruits were harvested at commercial maturity for marketing in late September, and treated with 70% N 2 O + 20% O 2 + 10% air, 80% N 2 O + 20% O 2 , and 90% N 2 O + 10% O 2 for 48 h, and then stored at 15℃. No significant treatments for soluble sugar and titratable acidity contents were detected. However, good appearance and taste in peach fruit were maintained better in 80% N 2 O treatment than in air treatment. The treatment with 90% N 2 O had negative effects on weight loss and taste because of rotting by anaerobic fermentation. 80% N 2 O treated fruit had significantly higher fungus (Botrytis cinerea) growth inhibition of saprogenic approximately than air treatment until 12 days of storage. The browning and rotting at surface of peach were also retarded when peaches were treated with 80% N 2 O before they were artificially wounded. The activity of polyphenol oxidase (PPO) was inhibited about 80% in peach of 80% N 2 O treatment compared with in air treatment. The result showed that 80% N 2 O treatment was able to extend the shelf life of peach fruits through maintaining taste and inhibition of softening and browning by rotting and wounding during storage.

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Polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS) blends were prepared using a high shear extruder to investigate their thermal decomposition and mechanical properties with shear rate and shear time. In this experiment, high shear rate, from 1000 to 3000 rpm, in blending process was applied for 10 to 40 sec, respectively. At high shear rate over than 2000 rpm, the initial decomposition temperature was dropped significantly compared to a compounded sample because of thermal decomposition of the blend by high shear. Consequently, high shear processing gave an important effect on the mechanical and thermal properties of the PC/ABS blend. In particular, elongation of the blend decreased significantly with shear rate.

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