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        검색결과 150

        141.
        2005.12 KCI 등재 서비스 종료(열람 제한)
        종실에 비해 다량의 rutin이 함유된 것으로 알려진 메밀 식물체의 최적 rutin함량 분석조건을 확립하기 위해 추출조건, HPLC 분석조건, 분석 재현성 및 최소검출한계를 검토한 결과 rutin은 미황색을 나타내는 폴리페놀 성분으로 에탄올에 용해 하여 최대 흡수파장을 측정하였을 때 359nm에서 흡수 극대파장을 나타내었다. 메밀 식물체 함유 rutin의 최적 HPLC분석 조건을 검토한 결과 컬럼은 Tosoh ODS 120T를 이용하고, 검출기 파장을 355nm, 이동상으로 A용매를 2~% 초산함유-45~% 아세토나이트릴로, B용매는 2~% 초산함유-증류수로 하여 농도구배조건을 0분 : 50~% A용액, 0-18분 : 100~% A용액, 18-20분 : 50~% A용액, 20-22분 : 50~% A용액으로 조절하고, 분당 1mL를 용출 하였을 때 가장 우수한 분리가 유도되는 것을 확인할 수 있었다. 또한 HPLC 분석요인에 대한 재현성을 검정한 결과 머무름시간, peak면적 및 peak높이의 변이 계수가 모두 0.6~% 미만을 나타내어 극히 높은 분석 재현성을 나타내는 것으로 조사되었으며, HPLC분석 시 최소검출한계는 20ng/mL수준이었다. 메밀 식물체 함유 rutin 분석을 위한 최적 추출조건을 검토한 결과 추출용매를 에탄올로 사용하고, 80℃ 조건에서 120분 이상의 환류추출을 시행하는 것이 가장 바람직한 추출법으로 조사되었다
        142.
        2002.04 KCI 등재 서비스 종료(열람 제한)
        The total hydrocarbon distribution of oil products obtained from the pyrolysis of four kinds of mixtures of polyethylene-polystyrene waste has been studied by multidimensional chromatography(high performance liquid chromatography followed by capillary gas chromatography)/mass spectrometry. Saturated, unsaturated and aromatic hydrocarbons in oil products were selectively pre-separated according to structural groups by HPLC and the weight fraction of each group was estimated by analysis of each component using GC-FID response factors. The hydrocarbon distribution of aliphatic fraction consists of C5 to C25 saturated and unsaturated hydrocarbons. And that of aromatics fraction consists of benzene, toluene, xylene, styrene, propenyl benzene, naphthalene, and some of derivatives. Pyrolysis temperature did not affect the ratio of total weight fraction of aliphatic over aromatic hydrocarbon distribution in case of PS only and PE-PS mixtures (1:1 and 1:4 wt. ratio) as a feed while affected the ratio of total wt. fraction in case of PE only. The optimal temperature for the maximum oil production was 600℃ for pyrolysis of PS and 1:1 and 1:4 mixtures of PE and PS. The optimal condition for aromatic recovery was 600℃ with 1:1 mixture of PE and PS. In this condition, aromatic was produced up to 90% of total oil product. The maximum yield of toluene, xylene, styrene, and propenyl benzene were 8.6, 8.9, 51.0 and 7.4% of feed for pyrolysis PS at 700℃, respectively. However, only 1.3% naphthalene was recovered at 700℃ with 1:1 PE:PS(by wt.).
        143.
        2002.04 KCI 등재 서비스 종료(열람 제한)
        The polycyclic aromatic hydrocarbons(PAHs) content in sewage sludge was determined by gas chromatography linked to ion trap mass spectrometry(GC/ITMS) with five deuterated PAHs as internal standards. The minimum detection limit was from 1.66 to 7.14 pg for individual PAH by GC/ITMS. For determining total PAHs(∑PAH) in sewage sludge 84 samples from 74 waste water treatment plants in whole country were analyzed. The average content of ∑PAH for whole samples was 3,289±3,098 μg/kg, and ranged from 142 to maximum 20,102 μg/kg. According to the number of population of the city, the areas were classified as five regions, ie. big, large, middle, small, and rural area in which the waste water treated plants were grown. The contents of PAHs were 4,689±5,503, 5,839±6,401, 3,725±2,053, 2,237±2,069, and 2,475±1,489 μg/kg, in big, large, middle, small, and rural area, respectively.
        144.
        2001.03 KCI 등재 서비스 종료(열람 제한)
        인삼의 주종 사포닌인 7종 사포닌(Rb1, Rb2, Rc, Rd, Re, Rf and Rg1)을 고속액체크로마토그라피로 분석하는 일반적인 방법인 순상 column에서 Rg1, Re 및 Rf가 명확히 분리되지 않는 문제점을 개선하기위하여 본 연구를 수행하였다. 고속액체크로마토그라피를 이웅하여 역상 μβondapak ODS컬럼으로 인삼중 주종 사포닌인 7종 ginsenosides Rg1, Re, Rf, Rb1, RC, Rb2 및 Rd를 양호하게 분리하였다. 이때 분석 조건으로 이동상 용매 조성은 (A) H2O, (B) methyl cyanaide을 (A) 90/(B) 10에서 (A) 0/(B) 100으로 기울기 용리를 이용하였으며, 기울기 용리 제어장치를 사용하여 용리시켰다. 용매 흐름속도는 1.5ml/min, 검출기는 UV detector(203nm)이었다. 이 방법은 분리능과 재현성 및 회수율이 양호하므로, 앞으로 인삼중 ginsenosides 분석에 응용될 수 있을 것으로 사료된다.
        145.
        1996.10 KCI 등재 서비스 종료(열람 제한)
        A method for the simultaneous analysis of 31 residual organic chloride pesticides was studied using gas chromatography. Prepared analytical samples were injected to gas chromatography (HP 5890 Series II plus) on the Ultra-2 column with ECD. The packing materials for column were changed as the following reagents ; florisil and alumina N. The residual solution was loaded to column and was eluted with elution solvents ; ether : benzene (2 : 8) solution, hexane : benzene (1:1) solution, dichloromethane, acetone, and methanol. The analytical results showed that 6 kinds of organic chlorides were not detected when florisil (first condition) was used as the column packing material. The nondetected 6 kinds of organic chlorides in the first analytical condition were detected and the recoveries of thrin-pesticides were increased, in particular, captan and captafol, but the recoveries of benzene hexachloride compounds were decreased when dichloromethane and methanol were added as elution solvents (packing material was florisil as in the first condition). The recoveries of dichlorfluanid, chlorofenvinfos, folpet, and dicofol were increased and that of aldrin was increased, but those of captan and captafol were not good when alumina N was used as the packing material. To detect simultaneously thrin-pesticides, captan, and captafol, florisil and alumina N were used as the packing materials. The elution result showed that captan and captafol were not detected. This was because the column was activated insufficiently. The analytical method was the best (31 kinds of organic chlorides in the residual pesticides were detected sharply and showed high sensitivity) when the column (packing materials were florisil and alumina N, together) was fully activated and the impurities were removed using various elution solvents.
        146.
        1996.10 KCI 등재 서비스 종료(열람 제한)
        The toxic substances (endotoxins) from the bacterial cell walls were extracted by using incubator, centrifuge, UV-Vis spectrophotometer, and their fatty acid compositions were analyze by Gas Chromatography. The lethal toxicities and pyrogenic activities of toxic substances were tested and the results were compared each other. The results of fatty acid analyses showed that the major fatty acid of the toxic substance was tetradecanoic acid for Vibrio vulnificus, dodecanoic acid for Escherichia coli and decanoic acid for Salmonella typhimurium. These three fatty acids were the main fatty acids for three toxic substances (more than 70%). The unique points in the fatty acid compositions were that tetradecanoic acid was composed as important one (37.15%) for V. vulnificus and that the amount of hexadecanoic acid was very small (below 2%) for three toxic substances. The lethal toxicity in ICR mice of toxic substance from V. vulnificus (LD_50 was 52.5 ㎎/㎏) was similar to that of E. coli (56.5 ㎎/㎏), but weaker than that of S. typhimurium (37.5 ㎎/㎏). Toxic substance from V. vulnificus was more pyrogenic in rabbit than that from E. coli, but less than that from S. typhimurium.
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