Tungsten nanopowders were produced by the method of wires electrical explosion in the different gases. The study of phase and dispersed composition of the powders was carried out. The influence of electrical parameters such as the value of energy input in wire and the arc stage of the explosion was discussed. The factors that make for decreasing the particles size are the lower pressure of surrounding gas and the use of addition of chemically reactive gas.

거베라 ‘Sunny Lemon'의 양액재배시 양액함량 조절이 생육 및 절화특성을 알아보고자 미치는 영향을 알아보고자 입상암면과 피트모스와 펄라이트 혼합배지(2:1, v/v)에 거베라 'Sunny Lemon' 유묘를 정식한 후 약 1달 동안 온실에서 순화시킨 후 배지내 양액의 함량이 각각 80-85%, 70-75%, 60-65%로 유지되도록 TDR센서(UT-TM, Ultra-Tech., Korea)를 부착하여 지속적으로 공급되도록 하였다. 양액은 거베라 sonneveld 양액을 1/2농도로 조성하여 초장이 평균 20±1 cm인 6월 24일 개시하였다. 영양생장에서 생식생장 전환 시점인 2개월 후 거베라의 생육을 조사한 결과, 배지종류에 따라서는 입상암면이 혼합배지보다 초장, 엽폭 및 엽수가 약 10% 더 증가되었지만 통계적으로 유의성은 없었다. 급액함량에 따라서는 2가지 배지 모두 배지내 양액 공급함량이 80-85% 때 가장 생육이 좋았으며, 생육초기보다 엽수는 약 60%이상, 엽폭과 초장은 약 40%정도 증가되었다. 첫 개화시점, 절화 품질 및 수량은 배지내 양액 함량이 높을수록 양호하였으며, 개화시점도 배지내 양액함량이 60-65%일때 보다 약 7-10일 빠른 것으로 조사되었다. 총 급액량은 입상암면보다 혼합배지내의 양액함량을 80-85%로 유지시킬 때 더 많이 소모되었으나, 배지의 EC, pH 변화는 입상암면에서 큰 것으로 보아 1회 정식 후 3년이상 재배되는 거베라 'Sunny Lemon'의 생육, 절화 품질 및 수량은 혼합배지에서 급액함량을 80-85%로 유지하여 재배할 때 가장 우수한 것을 알 수 있었다.

Murgot Looper Moth, Ascotis selenaria, is one of the worldwide pests in citrus plants. They usually damages citrus leaves and often makes young fruits injured. In Jeju, it has been discovered that A. selenaria is a pest of two major geometridae moths being occurred in citrus plant and they also had periodically occurred and damaged bean, asparagus, etc. However, physiological and ecological studies were rarely conducted on this species, which maybe resulted from the limitation of rearing method. Therefore, this study aimed on selecting the diet sources and developing mass-rearing method for A. selenaria, in order to make ease or spur a investigation related with A. selenaria. The major sources, selected among the series of semi-artificial diet, were corn and bean powder and adding yeast makes the larva developed well. Cholesterol, one of the minor sources, enhanced the development rate and lowered the mortality during 1 to 3 larva stage. Consequently the semi-artificial diet, suitable for rearing A. selenaria larva, was composed of 25g agar, 100g corn powder, 100g soybean powder, 30g yeast, 0.5g cholesterol, 2g Vanderzant's vitamin mixture, 2g Wesson's salt mixture, 2g sorbic acid, 2.5g methyl-4-hydroxybenzoate(MPH), 2g Ascorbic acid, and 1000 ml distilled water. A. selenaria larvae has 6 developmental stage and the width of head piece was 0.31 mm (1st instar) , 0.51 mm (2nd), 0.85 mm(3rd), 1.37 mm (4th), 2.14 mm (5th), and 3.19 mm (6th). The development period of A. selenaria, reared at 25℃ and 16L:8D photoperiod, was 4.7 day (egg), 3.58 day(1st instar), 1.88 day (2nd), 1.80 day (3rd), 2.46 day (4th ), 2.59 day (5th), 8.10 day (6th), 11.26 day (pupae) when citrus leaves were supplied to the larva. The larvae, fed with the artificial diet(mentioned above), showed similar developmental periods at each developmental stage as much as the case reared with citrus leaves, although the mortality was sometimes a little bit higher. The weight of pupae were 0.614g (artificial diet) and 0.427g (citrus stuff) and female adult moths lay 1094 eggs (artificial diet) and 1054 eggs (citrus stuff).