• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.192-197
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• 1998

사용후핵연료는 열전도도가 극히 불량하다. 그러므로 지금까지는 파단면을 관찰하거나 또는 성분분석을 위해 EPMA을 이용할 때는 시편 표면을 Au나 란소 등으로 증착시키고 있다 그러나 사용후 핵연료에서는 강력한 방사선이 방출되므로 시편의 증착처리는 핫셀(hot cell)에서 원격조정기(manipulator)를 사용하여 수행하므로 많은 어려움이 있다. 특히 시편 표면의 Au나 탄소의 증착시에는 균일한 증착이 필요한데, 핫셀내에 설치한 기기는 유지 보수의 어려움으로 양호한 진공도 유지가 어려워 시편 표면의 균질한 증착은 문제점으로 되어 있다. 이에 본 연구에서는 이산화우라늄 소결체를 표면의 증착처리 없이도 파단면 관찰이나 성분 분석을 할 수 있는 방법을 연구하여 silber paint법을 개발하였다. 특히 탄소가 미량 함유된 시편을 탄소 증착처리를 하면 증착된 탄소와 시편에 함유된 탄소를 분리해야 하는 어려운 점이 있으므로 이러한 경우에는 silber paint 법이 아주 편리하다.

• Proceedings of the KSCN Conference
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• 2004.05a
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• pp.413.2-414
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• 2004

본 연구는 건강피부를 유지, 관리하기 위한 기초 자료를 수립하기 위하여 외견상 건강하고 일상 활동을 유지하는 131명의 여대생을 대상으로 안면 피부유형별 신체지수 및 스트레스의 차이를 비교하였다. 피부유형은 전체안면 피부 유분량으로 판정하고 피부유형별 신체계측, 체성분 구성, 비만정도, 체형 및 스트레스정도의 차이는 SPSS11.0 (for Win)을 이용하여 분석하였다.(중략)

• Journal of Mushroom
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• v.18 no.1
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• pp.29-36
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• 2020

P. linteus (Korea Sanghwang, PLKS) and P. baumii (Jangsoo Sangwhang, PBJS) were artificially cultivated under the same conditions. Fruiting bodies were extracted using 70% methanol, 60% ethanol, and hot water. Phenol and flavonoid contents were optimally extracted using 60% ethanol. Antioxidant activities of 60% ethanol extracts from fruiting bodies and mycelia from each Sanghwang mushroom species were measured using DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2'-azino-bis (3-ethylbisthiazoline-6-sulfonic acid) radical scavenging activities, and FRAP (ferric reducing antioxidant power). The antioxidant activities of fruiting bodies were relatively higher in comparison to those of mycelial samples. In high performance liquid chromatography (HPLC) analysis, styrylpyrone-class poly phenolic compounds, davallialactone, hispidin, hypholomine B, and inoscavin A were detected in fruiting body samples of two Sanghwang mushroom species, but not in their mycelial samples.

• Food Science and Preservation
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• v.17 no.2
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• pp.261-266
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• 2010

Acidic hydrolysis conditions prior to HPLC analysis of plant flavonoids was investigated by response surface methodology (RSM), using leaves of Ginkgo biloba L. Ten hydrolysis conditions using 0.5-2.5 M HCl and 0.5-2.5 hr hydrolysis time were chosen to form a central composite rotatable design (CCRD), and optimization by RSM was achieved by measuring myricetin, quercetin, and kaempferol levels by HPLC. Optimum hydrolysis condition was 1.5 M HCl for 1.5 hr. The levels of flavonoids obtained under the condition were in good agreement with predicted maximum values, with yields of more than 95%. These optimum hydrolysis condition was applied to analysis of flavonoid content in the leaves of Camellia sinensis, Ficus carica, and Sageretia theezans.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2003.11a
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• pp.244-250
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• 2003

With a recent public concern rising on the radioactive waste, it is disclosed that the problem is more serious than expected. This research has been conducted to find effects of yellow sandy rainwaters on the solidified cement of mid-and-low level radioactive waste. The ANS 16.1 standard test method was chosen for this leaching experiment. Make a cement solidified radioactive waste that contains Co nuclide, and fabricate it for over 28 days. Then, decide on the volume of leaching water and the concentration of ion and metal in leachate from the mass concentration of yellow sands in atmosphere. In this paper, we have taken a short look at characteristics of yellow sand. Before going into the leaching experiment, we decided experimental conditions first. Then, it was evaluated and analyzed how sandy rainfalls have impact on the cement solidified radioactive waste based on data from 90 days of leaching experiment.

• Journal of Mushroom
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• v.10 no.4
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• pp.224-235
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• 2012

Quality change of winter mushroom were investigated during storage and distribution phase as influenced by storage temperature. According to storage period and temperature, amino acids, were analysed and quantified with the mushroom fruiting bodies using HPLC and morphological characteristics were investigated. Characteristic changes of winter mushroom fruiting bodies were described as follows during storage according to the storage temperature. Looking at the results of the analyzed amino acid contents, temperature between $-1^{\circ}C$ and $4^{\circ}C$ was optimal condition for the storage. At $4^{\circ}C$, the chemical composition tended to be maintained. On the other hand, the results indicate the rapid loss of nutrition at $-1^{\circ}C$ within 7 days of storage. Exceptionally, proline was shown to be increased. Brown line mushroom had a larger loss than white line mushroom. Based on this result, brown line mushroom have shown significant differences among varieties. Therefore, winter mushroom should be stored at $4^{\circ}C$ to minimize nutrient loss and to maintain freshness and mushrooms should be consumed within 14 days after harvest.

• Analytical Science and Technology
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• v.22 no.1
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• pp.65-74
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• 2009

Active components of lacquer tree referred to as urushiol congeners, which are catechol derivatives with various alkyl or alkenyl substituents. The olefin side chains typically have one, two or three double bonds. In this study, the each congener's ratio analysis of extracts from korean lacquer tree are compared to the one from other asian lacquer tree. Extraction was performed using liquid-liquid extraction (LLE) method with soxhlet system from tree's bark and sap. Extracts were analyzed by reverse phase liquid chromatography and on-line electro spray ionization mass spectrometry (LC-MS/MS).

• Journal of Life Science
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• v.20 no.1
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• pp.9-16
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• 2010

This study investigated cut-off values of body mass index (BMI) and body fat measures for metabolic syndrome (MS) in elderly Koreas. Questionnaire surveys, anthropometric measurements, medical examinations, and body composition analyses were conducted for 10,077 subjects aged 40-65 years in the health examinee cohort in Korea between 2004 and 2006. Cut-off values were identified using receiver-operating characteristic (ROC) curve analysis for both men and women. Stratified analyses by weight range (<60, 60-69, 70-79, and 80-89, ${\geq}90\;kg$ for men; <50, 50-59, 60-69, 70-79, ${\geq}80\;kg$ for women) were conducted. Among male subjects, the cut-off points were $25.5\;kg/m^2$ for BMI with a sensitivity of 70.0% and a specificity of 72.0%, and 26.1% for body fat percentage with a sensitivity of 60.6% and a specificity of 76.4%. Among female subjects, the cutoff points were $24.1\;kg/m^2$ for BMI with a sensitivity of 73.3% and a specificity of 68.8%, and 31.5% for body fat percentage with a sensitivity of 76.7% and a specificity of 65.6%. Stratified analysis by weight range showed that the cutoff points of BMI and body fat measures tended to higher as weight level increased. The results of our study suggest cut-off values of BMI and body fat measure for MS were similar to the general obesity criteria in Korea.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.226-227
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• 2001

어류에서 steroid hormone은 그 분자 구조를 변환시켜, 물질대사를 증진시킴과 동시에 androgen효과를 억제 시킴으로서 어류 양식산업에서 성장촉진제로 사용되고있다(Higgs et al., 1982). 동자개 Pseudobagrus fulvidraco(Siluriformes, Bagridae)는 우리나라의 황해와 남해로 유입되는 유속이 완만한 하천의 모래나 진음이 많은 바닥에 서식하고, 국외로는 중국. 대만 및 시베리아 동부에도 분포하고 있으며(김,1997) 현재 양식 산업화가 진행되고 있는 어종이다. Tamoxifen은 동자개에서 효과적인 성전환 효과를 보이는 비 steroid계 hormone임이 이미 밝혀진 바(김, 1999),본 연구는 양식 산업성 증대 목적으로 tamoxifen 첨가 먹이 공급시 체성분을 분석하여 그 효과를 평가하고자 한다. (중략)

• The Korean Journal of Pesticide Science
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• v.13 no.3
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• pp.133-147
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• 2009

In order to develop the simultaneous analytical method for pesticide residues which ones in soil are rapidly and inexpensively measured by, many analytical methods for individual pesticide residue and several methods for multi-pesticide residues in agricultural commodities and food were reviewed. Various gas chromatographic conditions and pre-treatment procedures were intensively investigated and modified. And then new optimum procedure was established and its proficiency was validated. The response on detectors of simultaneous determination of 180 pesticides out of pesticides used in Korea was tested. The number of pesticides that their limits of detection (LOD) equal or lower than $0.05\;mg\;kg^{-1}$ were 137 pesticides on ECD, 170 pesticides on NPD and 179 pesticides on ECD/NPD integrated. The retention times of most pesticides ranged appropriately between 10 minutes and 40 minutes in the proposed chromatographic conditions. But about 90 pesticides eluded between 20 minutes and 30 minutes and so they were not resolved enough. In partition with dichloromethane, ethyl acetate/hexane (1:1) and ethyl acetate, number of pesticides whose extraction efficiency ranged from 70% to 120%, were 163, 154 and 147, respectively.