In Korea, a small proportion of fishery products are contaminated with a considerable amount of potentially hazardous contaminants. So, there is generally a high risks to consumers. Inorganic contaminants with the greatest potential for toxicity are Sb, As, Cd, Pb, Hg, Se and the Sulfides. As appears to be much more variable than the others. This study was performed to assess the levels of the As in fisheries caught from the waters of the western coast of Korea. The samples included 26 kinds of fishes, 18 kinds of Mollusca, 3 kinds of Crustacea and 7 kinds of salted fishes. The Moisture content of molluscans was significantly higher than that of others (p$lt;0.05). And the As contents of crustaceans were significantly higher than those of fishes, molluscans and salted fishes (p$lt;0.05). The As content of Turban shell was 51.62 ppm, which was the highest among the samples. Also, the As contents of eel, cattle fish and blue crab were found to be higher than in other fisheries. This variability offers a solution for the reduction of eosure to As through restricting the harvest of aquatic organism from the western coast of Korea.
Effects of various jelly prepared with different concentrations of agar and sugars on overall acceptability of the peach jelly were investigated. The preparations of peach for experimental jelly were carried by the mixture of peach pulp and juice(MPJ), and the extracts from peach(EP). The results were summarized as follows ; 1. The pH for MPJ and EP were 3.95 to 4.31 and 4.21, respectively, and the brix degree were 13.0% and 11.5%, respectively. 2. The jelly prepared with MPJ added 3% sugar and 30% sugar were most effective in appearance, hardness, springiness and overall acceptability. The relation of samples(P<0.001) was found to be significant. On the other hand, the jelly prepared with EP was higher scored than that with MPJ in overall acceptability, but there was no significant differences between samples. 3. The Hunter values of L^*, a^* and b^* were the highest in both the jelly prepared with MPJ and that with EP, added 2% ㅁgar and 10% sugar. However, the L^*, a^* and b^* values of the jelly added MPJ were higher than those of the sample added EP. 4. Texture and color scores of both the jelly added EP became higher as the concentrations of agar and sugars increased and there was significant differences between samples. 5. The relation between springiness and overall acceptability, and L^* value of the jelly added MPJ showed negative at P<0.05. And that between springiness and overall acceptability of the jelly added EP also showed negative.
본 실험은 수경재배에서 딜의 양수분 흡수 패턴을 밝히고 생육과 환경특성에 적합한 배양액을 개발하여 실제 재배에 응용하고자 수행하였다. 이를 위해 딜의 양분 홉수율에 의한 배양액을 조성하였으며 그 적합성을 검정하기 위해 기존배양액과 비교실험을 실시하였다. 딜의 NFT재배에 적합한 배양액을 개발하기 위해서 일본야채시험장 표준액을 1/4배액, 1/2배액 및 1배액으로 조성하여 재배한 결과, 1/2배액에서 생육과 수량이 가장 높았으며 근권내 pH와 EC의 변화도 안정되었고, 식물체내 무기이온 합량도 적정치로 나타나 딜의 양분흡수특성에 적합할 것으로 판단되었다. 따라서 일본야채시험장 1/2 배액의 양수분 흡수율(n/w)을 기준으로 새로운 배양액을 조성하였으며, 이온의 조성은 NO3―N 8.85, NH4―N 0.55, P 2.1, K 6.2, Ca 2.8, Mg 1.7 me.L-1였다. 딜의 순환식 NFT 재배용으로 개발한 배양액의 적합성 검정실험 결과, 근권내 pH와 EC는 저농도인 SCU 1/2배액을 제외하고는 변화폭이 크게 나타나지 않았다. 본 실험에서 개발된 SCU 1배액은 기존에 허브 배양액으로 사용된 일본 야채 시험장 배양액과 비교할 때 생육과 수량면에서 우수하였으며, 엽내 무기성분 함량도 적정수준을 나타내었다. 따라서, 본 실험에서 개발된 SCU 배양액은 딜의 NFT재배에 적합한 배양액이라 할 수 있다.
(NdㆍDy)-(FeㆍCoㆍAIㆍM)-B 합금에 Sn,Mo등을 첨가하여 그에 따른 미세구조와 열적안정성 및 자기적 특성 변화를 조사하였다. Sn과 Mo의 첨가는 (NdㆍDy)-(FeㆍCoㆍAIㆍM)-B 합금리본의 큐리온도를 크게 향상시켰으며 자기특성, 특히 보자력을 1KOe이상 증가시켰다. 그리고 이러한 현저한 보자력 증가는 입계형 defect인 disturbed grain boundary defect에 기인하는 것이라 판단되었다. 또한 Sn과 Mo 첨가원소는 irreversible loss를 각각 4%와 6% 감소시켜 리본자석의 열적안정성을 향상시켰다. 이는 Sn과 Mo의 첨가가 보자력을 크게 증가시켰기 때문이다. 한편 (NdㆍDy)-(FeㆍCoㆍAIㆍM)-B 리본자석들의 열저항온도(heat resistance temperature)는 irreversible loss와 직선관계를 이루었다.
6-[(N-3,4-Dibromophenyl)amino]-7-chloro-5,8-quinolinedione(RCK13) was tested for antifungal activities. The MIC values were determined by the two-fold dilution method. The therapeutic potential of RCK13 had been assessed in comparison with ketoconazole and fluconazole against systemic infections with Candida albicans in normal mice. RCK13 had ED_(50), 0.80±0.21 mg/kg but ketoconazole had ED_(50), 8.00±0.73 mg/kg respectively. And administered RCK13 at the ED_(50) for 14 days improved survival rates as well as ketoconazole. Acute oral toaicity studies of RCK13 were carried out in ICR mice of both sexes. These acute oral toxicities of RCK13 were low and LD_(50) values were over 2,850 mg/kg in ICR mice. The genotoxicities of RCK 13 had been evaluated. RCK13 was negative in Ames test with Salmonella ryphimurium and chromosomal aberration test in CHL cells. The clastogenicity was tested on the RCK13 with in vivo mouse micronucleus assay. RCK13 did not show any clastogenic effect in mouse peripheral blood and was negative in mouse micronucleus assay. These results indicate that RCK13 has no genotoxic potential under these experimental conditions.
열가소성 고분자 복합재료 개발을 위하여 매트릭스 수지로는 폴리프로필렌섬유(PP)를 사용하고 유기계 강화소재로 폴리비닐알코올(비닐론, VF), 아라미드(케블라-49, KF) 및 폴리아미드섬유(PAF)등을 사용하였다. 복합매트제조장치로서 복합매트를 제조하고 가열.압축하여 고분자 복합재료를 성형하였다. 제조한 고분자 복합재료의 형태학, 유변학적 및 기계적특성 등을 측정하였다. 형태학에서 미트릭스와 강화섬유 간의 젖음성은 강화섬유의 함량이 증가함에 따라 감소하는 경향을 보였다. PAF/PP와 VF/PP 복합재료에 대한 점성도는 낮은 주파수 영역에서 강화섬유의 함량이 증가됨에 따라 증가하였으나, 높은 주파주 영역에서 5-20wt%로 강화된 복합재료는 매트릭스인 PP에 근접하게 감소된 점성도를 나타냈다. 기계적 특성은 강화 섬유의 함량에 따라 변하였으며, VF/PP 및 KF/PP 복합재료가 PAF/PP 계에 비해 우수한 현상을 보였다.
버즘나무를 가해하는 우리나라 미기록 해충이 발생되어 동정한 결과 버즘나무방패벌레(신칭)로 확인되었다. 성충은 체장이 3.0~3.2mm이며 외견상 유백색을 띠고 있고 노숙약충은 검은색을 띠고 있다. 버즘나무의 잎 뒷면에 모여 흡즙 가해하며 피해엽은 황백색으로 변한다. 본 해충은 1995년 9월말 현재 서울, 경기, 강원, 충북, 충남 등 중부지방에 분포하고 있는 것으로 나타났다.
The objective of this study is to investigate the direct effects of green tea catechins(GTC) on vascular smooth muscle tension and ^(46)Ca^(2+) uptake in rat aorta. The methods used in this study are isometric tension measurements using physiograph, Lanthanum method for ^(46)Cac^(2+) (2 uCi/ml) uptake measurement in rat aorta. GTC modified tension induced by 40 mM KCl or 1 uM norepinephrine in rat aorta. Low concentrations of GTC($lt;0.5 mg/m increased tension by 40 mM KCl or 1 tM norepinephrine, individually. However, high concentrations of GTC($gt; 0.5 mg/ml) inhibited tension by 40 mM KCl or 1 uM norepinephrine, individually. GTC increased ^(45)Ca uptake induced by 40 mM KCl in a dose-dependent manner. From these results, GTC has the dual actions in vascular smooth muscle in vitro. Low concentrations of GTC augments tension by K or norepinephrine. However, high concentrations of GTC inhibits tension by K or norpeinephrine. GTC may have Ca^(2+) channel activation action, which may result in unphysiological vasodilation by Ca^(2+) overload in vascular smooth muscle.
Green tea catechins(GTC) were studied for its inhibitory effect on human platelet aggregation in vitro, for its antithrombotic effect in mice in vivo, and for bleeding and clotting time in rats. The catechins were isolated and purified from green tea, which were composed of (-)-epigallocatechin gallate, (-)-epigallocatechin, (-)-epicatechin gallate and (-)-epicatechin. GTC produced a potent inhibition of human platelet aggregation in a dose-dependent manner against the stimulants such as ADP, collagen, epinephrine and ristocetin in vitro. GTC also prevented death due to the formation of pulmonary thrombosis by platelet aggregates in mice in a dose-dependent manner in vivo. GTC increased the bleeding time, whole blood clotting time and plasma clotting time in rats, too. These results suggest that GTC is a promising antithrombotic agent.
The genotoxicity of combinations of four p-oxybenzoic acids (methyl paraben, ethyl paraben, isopropyl paraben, butyl paraben) and benzoic acid had been evaluated. The in vitro Ames test using Salmonella typhimurium (TA 98, TA 100, TA 1535, TA 1537) and the in uiuo micronucleus assay using mouse peripheral blood were performed. Methyl paraben plus benzoic acid, ethyl paraben plus benzoic acid, and ethyl paraben plus butyl paraben slightly increased the frequency of micronucleated reticulocytes in the high doses, but were negative in Ames test with Salmonella typhimurzum with and without rat liver microsomal activation. The other combinations tested were negative in Ames test and did not show any clastogenic effect in micronucleus test. These results suggest that genotoxicity can produced by the combinations of p-oxybenzoic acid.
One of the main problems in evaluating complex objects, such as an ill-defined system, is how to treat ambiguous aspect of the evaluation. Due to the Complexity and ambiguity of the objects, many types of evaluation attributes should be identified based on the rational dsision. One of these attributes is an analytical hierarchy process (AHP). the weight of evaluation attribtes in AHP however comes from the probability measure based on the additivity. Therefore, it is notapplicable to the objects which have the property of non-additivity. In the previous studies by other researchers they intriduced the Hierarchical Fuzzy Integral method or mergd AHP and fuzzy measure for the analysis of the overlaps among the evaluation objects. But, they need more anlyses in terms of transformation of the probability measure into fuzzy measure which fits for the additivity and overlapping coefficient which affects to the fuzzy measure. Considering these matters, this paper deals that, ⅰ) clarifying the relation between the fuzzy and probability measure adopted in AHP, ii) calculating directly the family of fuzzy measure from the overlapping coefficient and probability measure. A simple algorithm for the calculation of fuzzy measures and set family of those from the above results is also proposed. Finally, the effectiveness of the algorithm developed by applying this to the problems for estimation of safety in ship berthing and for evaluation of ports in competition is verified. This implied that the new algoritnm gives better description of the system evaluation.
고주파 이동통신의 효용이 증가할수록 고주파 회로에 들어가는 부품들의 소형화가 중요한 과제로 대두되고 있다. 인덕터는 전자회로에 이용되는 주요 부품의 하나이며, 현재 교주파용 소형 인덕터를 박막화하려는 시도가 진행중이다. 본 연구에서 열산화시킨 Si(100)기판위에 성공적으로 박막형 인덕터를 제조하였다. Core 물질로는 ion beam sputtering 법으로 증착한 Ni-Zn 페라이트와 PECVD법으로 증착한 SiO2를 사용하였다. 고온산화분위기의 박막 증착과정을 고려하여 귀금속류인 Au를 전극으로 이용하였으며, life-off법으로 미세회로를 구현하였다. 상하부 전극의 안정적인 연결을 위하여 2차 전극배선 전에 via를 채워넣었다. 제조된 박막 인덕터의 고주파 특성은 network analyzer로 측정한 후 HP사의 Mecrowave Design System으로 분석하였다.