Two different casting speeds of 60 and 80mm/min are adopted to determine the effect of casting speed on the microstructure and mechanical properties of Al-Mg-Si/Al hybrid material prepared by duo-casting. The obtained hybrid material has a uniform and straight macro-interface between the pure Al side and the Al-Mg-Si alloy side at both casting speeds. When the casting speed is increased to 80mm/min, the size of primary α phases in Al-Mg-Si alloy decreases, without change of shape. Although the Al-Mg-Si alloy produced at higher casting speed of 80mm/min shows much higher ultimate tensile strength (UTS) and 0.2 % proof stress and lower elongation, along with higher bending strength compared to the case of the 60mm/min in casting speed, the tensile properties and bending strength of the hybrid material, which are similar to those of pure Al, are the same regardless of the increase of casting speed. Despite the different casting speeds, deformation and fracturing in hybrid materials are observed only on the pure Al side. This indicates that the macro-interface is well-bonded, allowing it to endure tensile and bending deformation in all hybrid materials.

In this study, three kinds of metal chills such as SS400, AC4CH and brass, with different thicknesses of 40 ~ 80 mm, were applied for low pressure casting of Al-Si alloy to control cooling rate. The microstructural characteristics with increasing cooling rate were represented using factors including D1, D2, size of primary α phases and shape factor and size of eutectic Si. The tensile properties were investigated and additionally analyzed based on the microstructural characteristics. As the cooling rate increased, D1, D2, and sizes of primary α phases and eutectic Si apparently decreased and the shape factor of eutectic Si increased to over 0.8. The ultimate tensile strength (UTS) and yield strength (YS) increased with decreasing D1, D2, and size of primary α phases, while elongation increased with decreasing size of eutectic Si and concurrently increasing shape factor of eutectic Si. This indicated that the primary α phases and eutectic Si in Al-Si alloy were refined with increasing cooling rate, resulting in improvement of UTS and YS without sacrificing elongation. After the tensile test, preferential deformation of primary α phases was observed in the Al-Si alloy produced at higher cooling rates of more than 0.1 K/s.

답전윤환 옥수수 8품종 및 수수 7품종 재배포장에서 조명나방 발생 및 수확 특성을 조사하였다. 매주 이뤄진 성충 트랩 조사에서 조명나방 밀도는 정식 2주 후부터 급격히 증가하여 6월 중순에 최성기에 도달 후 감소하다 9월 초 소폭 증가 후 감소하였다. 조명나방 유충에 의한 피해주 수와 침입공수를 매주 옥수수 미백2호와 대학찰 그리고 수수 남풍찰과 동안메를 대상으로 조사하였다. 그 결과, 대학찰과 미백2호에서 피해주가 각 20주당 19주와 18주였고, 주당 침입공수도 6월말부터 꾸준히 증가하여 수확기인 7월말에 대학찰은 주당 평균 1.8개, 미백2호는 1.4개로 나타 났다. 수확기에 옥수수 8품종에 대한 피해율과 침입공수를 조사한 결과, 대학찰 94%, 미백2호 92%, 일미찰 71%, 얼룩찰1호 64%, 찰옥4호 54%, 미흑찰 52%, 흑점2호 45%이었다. 주당 침입공수는 일미찰이 1.21개였고 나머지 품종들에서는 1개 미만이었다. 또한 옥수수 각 품종별로 이삭 10개씩 3반복으로 조명나방 유충에 의한 이삭 피해율을 조사한 결과, 일미찰 50%, 흑진주찰 40%, 대학찰 37%, 미흑찰과 흑점2호 13%, 얼룩찰 7% 그리고 미백2호 3% 등이었다. 수수 주요 재배품종들인 남풍찰 및 동안메는 정식 후 2개월까지 20주 평균 4주 미만으로 피해를 입다가 8월 초 에 피해가 급증하여 평균 피해주는 남풍찰이 13주, 동안메는 9.2주였고 주 당 침입공수도 8월 초부터 나타나기 시작해 남풍찰은 주당 평균 1.06 개, 동안메는 주당 평균 0.46개였다. 수확기 수수 품종별 조명나방에 의한 피해율을 조사한 결과, DS-202 95%, 목탁수수 76%, 소담찰 75%, 남 풍찰 67%, 앉은뱅이수수 57%, 동안메 46% 그리고 황금찰 34%로 7품종 모두 조명나방에 의해 높은 피해를 입었다. 침입공수 또한 피해율에 비 례해서 DS-202(1.7개), 목탁수수(1.4개), 소담찰(1.3개), 남풍찰(1.1개), 앉은뱅이수수(1개), 동안메(0.5개) 그리고 황금찰(0.4개)로 관찰되었다. 한편, 답전윤환 옥수수 및 수수 포장에서 조명나방 피해와 수확 특성은 인과관계를 보이지 않는 것으로 나타났다. 이상의 결과는 답전윤환 옥수수 및 수수 재배포장에서 조명나방의 관리대책을 구축하는데 활용될 수 있을 것으로 기대한다.

연두금파리의 난세포성숙에 따른 단백질의 변화와 난특이성단백질의 특성을 확인하기 위하여 gel filtration, 전기영동 및 분자량측정, 아미노산과 지방산함량을 측정하여 얻은 결과는 다음과같다. 연두금파리 암컷성충의 난소단백질은 단백질원을 섭식시킨 후 72시간 이후 빠르게 증가하였고, 완전한 성숙이 일어나는 96시간에 최고의 함량을 나타냈다. DEAE-cellulose와 Sephacryl 5-200으로 gel filtration하고 7.5% native polyacrylamide gel에서 전기영동한 결과 난소에서 분리된 특이단백질은 0.4에서 혈림프 및 난소와 다른 밴드가 확인되었으며, 분자량은 110,000 dalton이였다. 분리된 난특이성단백질내 아미노산 조성은 asparagine 외 모두 13종이 검출되었으며, asparagine, glutamic acid와 함께 tyrosine이 특이하게 높게 나타났다. 지방산은 난소와 함께 난특이성단백질에서 palmitic acid의 4종이 분리되었다. 따라서, 연두금파리의 난에는 지방체에서 합성, 분비된 난황단백질이외에 난소에만 존재하는 특이단백질이 있음을 알 수 있다.

This study was conducted at rearing room to investigate the feeding behavior of fruits in the firefly (Pylocoelia rufa) larvae and the ovipositional characteristics of the adults. As a result, the pear, apple, melon, persimmon, mandarin, grape and peach were shown the feeding behavior of larvae the average 6.40, 3.25, 2.50, 2.20, 2.00, 1.40 and 1.25, respectively. However, the larvae were not shown at all feeding behavior to banana. The hours feeding behavior of firefly larvae was primarily from 8:00 pm until 2:00 am. In addition, the time at which the voracious feeding behavior was until 8:00 pm to 12:00 pm. The 6:00 pm began whisking all the larvae are hiding in the shelter. In the case of the firefly larvae fed only the edible snail, the adults were oviposition an average 49 ± 6 eggs. At that time larva stage, adults of the firefly eating the pears, apples, melon and eat edible snail at the same time there were oviposition the 53 ± 7 on average. In the case of fruits, the pears, apples, and melons has been considered worthy to take the firefly larva fed with the current land snails.

In the growth of the Rubus coreanus Miquel fruits, the unripened (10 days) and ripened (25 days) fruits after flowering were harvested. The chemical characteristics of different maturational stages of the unripened and ripened fruits were investigated. Total amount of phenolic compounds was 4.00-7.56% in the unripened fruits and 3.78-5.57% in the ripened fruits, respectively. Furthermore, total amounts of organic acids such as malic, citric, succinic, and oxalic acids were 16.40 mg/ 100 g in the unripened fruits and 28.82 mg/100 g in the ripened fruits, respectively. In organic acids of the unripened and the ripened fruits, citric acid (8.76-15.47 mg/100 g) was the highest amount among other organic acids. Soluble sugars were significantly increased from 11.07 to 21.54% in the unripened and ripened fruits. Therefore, ripened fruits had the high levels of phenolic compounds, organic acids and soluble sugars. For the biological studies of R. coreanus, methanol extracts of R. coreanus leaves, fruits, and stems were evaluated for their insecticidal activities against Myzus persicae (Hemiptera: Aphididae), Plutella xylostella (Lepioptera: Plutellidae) and Spodoptera litura (Lepioptera: Noctuidae) by leaf dipping method. From these results, the extract of R. coreanus leaves revealed potent insecticidal activity against P. xylostella. However, the methanol extracts of R. coreanus fruits and stems had no any insecticidal activity against M. persicae, P. xylostella and S. litura. The R. coreanus leaves have promising potential as new insecticidal agent against P. xylostella.

In order to breed the useful mutants in black raspberry, cultivated in Gochanggun, leaf-petiol explants from shootproliferating culture was regenerated after irradiated with 30, 50 and 70 Gy gamma-ray and seeds were irradiated with 100, 130, 150, 170 and 200 Gy gamma-ray. The LD50 dose of leaf-petiol explants and seeds in black raspberry was identified as 30 and 150 Gy after two months and one month, respectively. The mutants such as leaves with increasing width, chlorophyll content and increasing anthocyanin were selected in regenerated explants and seeds irradiated. The increased rate of leaves width and chlorophyll were 33.3% and 23.1% compared to the control. Also, antocyanin concentration in leaf of mutnats from irradiated seeds was increased till 17.3%. For the breeding of black raspberry, valuable mutants obtained will be expected for improving photosynthesis efficiency and functional components, and will be useful for developing new cultivars.