Vortex tube is a simple structure and environmentally friendly method of temperature separation. In this paper, the applicability of the vehicle air conditioning system using the Vortex tube was reviewed. Experimental conditions, the pressure was set at 0.5~5.0kgf/cm2, and the cold air flow ratio (yc) was set at 0.1~0.9. Experiment result, the high temperature section represents the highest temperature value at yc=0.8. The cold zone represents the lowest temperature value at yc=0.5. In case of indirect heat exchanger experiment result, the maximum temperature difference was 11°C in the cold zone and 15°C in the hot zone. In case of direct heat exchange, the low temperature area was 11°C and the high temperature area was 11°C. According to the experiment result, although indirect heat exchange method performs better than direct heat exchange method, the time to reach normal temperature is four times slower than direct heat exchange method. Therefore, in order to apply to a vehicle air conditioning system, it is judged that it is effective to use a direct heat exchange method having a fast reaction speed and a low flow rate resistance.

Since single-use disposable plastic usage has steadily been increasing, recent trends in polymeric research point to increasing demand for eco-friend materials which reduce plastic waste. A huge amount of non-degradable polypropylene (PP)-based pots for seedling culture are discarded for transplantation. The purpose of this study is to investigate an eco-friendly biodegradable material as a possible substitute for PP pot. The blend of poly(lactic acid) (PLA) with poly(butylene adipate-co-terephthalate) (PBAT) was used because of its good mechanical and flexible properties as well as biodegradation. After landfill, various properties of the blend pot were investigated by UTM, SEM, NMR and TGA. The results showed the tensile strength of the blend film rapidly decreased after 5 weeks of landfill due to degradation. From NMR data after landfill, the composition of PLA in the blend was decreased. These results indicate that the biodegradation of the blend preferentially occurs in PLA component. To investigate the effect of holes in pot bottom and side on root growth, a plant in the pot was grown. Some roots came out through holes as landfill period increases. These results indicate that the eco-friendly pot can be directly planted without the removal of pot.

이산화염소수 또는 푸마르산이 전처리된 고추, 생강, 당근의 초기 미생물수 감소 효과에 관한 연구를 하기 위하여 이산화염소수 5, 10, 50 ppm과 푸마르산 0.1, 0.3, 0.5%를 고추, 생강, 당근에 5분간 각각 처리하였다. 이산화염소수와 푸마르산 전처리는 총균수, 효모와 곰팡이 수를 유의적으로 감소시켰는데, 특히 50 ppm의 이산화염소수를 고추에 처리 시 총균수, 효모 및 곰팡이 수가 1.52, 1.81 log CFU/g 감소시킨 반

Maltodextrin 농도 30, 50, 80% 처리로 고추를 건조 한 후, 동결건조와 열풍건조 처리된 시료와 복원율, 색도, 관능 평가를 비교, 분석 하였다. 고추의 수분함량 측정 결과, maltodextrin의 농도가 높을수록 최종 탈수되는 수분량은 많았고, 건조된 고추의 복원율은 maltodextrin 처리가 다른 건조 방법 보다 높은 복원율을 가졌다. 색도에서는 동결 건조와 유사하였고 열풍건조 보다는 우수하였다. 관능 평가에서는 동결건조