• 한국식품과학회지
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• 제33권4호
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• pp.416-422
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• 2001

식품포장용 PVC제인 wrap, sheet 및 gasket으로부터 식품 유사용매와 식품으로 이행되는 알킬페놀류를 HPLC와 GC/MSD로 분석하였다. 세 가지 모든 재질에서 7개의 nonyl phenol 이성질체만이 검출되었고 다른 알킬페놀류는 검출되지 않았으며, wrap이 sheet와 gasket보다 그 함량이 높았다. 각 포장재질로부터 수용성 식품유사용매(증류수, 4% acetic acid, 20% ethanol)와 지용성 식품유사용매(n-heptane)에 의한 nonyl phenol의 용출량은 처리온도 $60^{\circ}C$보다는 $95^{\circ}C$에서, 수용성보다는 지용성 식품유사용매에서 각각 많았고, 또한 wrap에서 sheet와 gasket보다 그 양이 많았다. PVC gasket을 사용한 과일쥬스, olefin계 gasket을 사용한 유아용 쥬스, olefin계 병마개를 사용한 음료에서 nonyl phenol이 각각 포장재로부터 이행되었으며, 포장하기 전의 이들 식품에서도 nonyl phenol이 검출되었다.

• 생약학회지
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• 제45권4호
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• pp.300-314
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• 2014

An ultra-performance liquid chromatography-electrospray ionization-mass spectrometer (UPLC-ESI-MS) method was established for the simultaneous quantification of eighteen marker compounds in traditional Korean formula, Cheonwangbosimdan (CWBSD). In addition, we evaluated the antioxidant effects of CWBSD. Eighteen marker components were separated on a UPLC BEH $C_{18}$ analytical column ($2.1{\times}100mm$, $1.7{\mu}m$) and kept at $45^{\circ}C$ by gradient elution with 0.1% (v/v) formic acid in water and acetonitrile as mobile phase. The flow rate was 0.3 mL/min and the injection volume was $2.0{\mu}L$. The antioxidant activities of CWBSD were assessed by measuring free radical scavenging activities on 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 1-1-diphenyl-2-picrylhydrazyl (DPPH). The calibration curves of all analytes showed good linearity (correlation coefficient ${\geq}0.9937$) within the test ranges. The limits of detection and quantification for the 18 marker compounds were 0.01-4.71 ng/mL and 0.03-14.13 ng/mL, respectively. The contents of the 18 compounds in CWBSD extract ranged from none to $1701.00{\mu}g/g$. The CWBSD showed the radical scavenging activity in a dose-dependent manner. The concentration required for 50% reduction ($RC_{50}$) against ABTS and DPPH radicals were $149.42{\mu}g/mL$ and $339.24{\mu}g/mL$.

• 터널과지하공간
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• 제10권2호
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• pp.196-210
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• 2000

본 연구는 현재 한국도로공사에서 시행하고 있는 강섬유보강 숏크리트(SFRS)의 휨인성 평가 방법에 대한 타당성을 검증하기 위하여 수행되었다. 시료는 6종류의 강섬유를 사용하여 33개의 삼등분점굴곡시험용 빔 블록을 현장 타설 후 양생한 후 절단, 제작하였으며, 휨인성시험은 실험실에서 실시하였다. 한국도로공사의 시험지침을 따라 등가휨강도 및 인성계수를 산정하였으며, 이 결과는 ASTM, ITA 및 EFNARC의 평가 기준을 적용한 결과와도 비교하였다. 연구 결과 한국도로공사 평가 방법에서는 인성계수가 휨강도의 영향에 의하여 평가 결과에 모호성이 있는 것으로 판단되었다. 이를 수정하기 위하여 인성계수의 계산에 적용되는 휨강도를 설계 시에 설정된 설계휨강도로 대체, 적용하는 방법이 보다 적절히 SFRS의 휨인성을 평가할 수 있는 것으로 판단된다.

• 한국식품영양학회:학술대회논문집
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• 한국식품영양학회 2001년도 동계 학술심포지움
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• pp.126-126
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• 2001

The Rhus verniciflua contains alkly(en)-catechol type allergens with a saiurated or unsaturated alkly chain of 15 or 17 carbon atoms. It has been recognized as an extremely active allergen causing skin reactions similar In poison ivy. The allergic contact dermatitis induced by the urushiol is known to be mediated be T lymphocytes whicht specifically recognize the hepten urushiol. Therefore. direct use of this plant as a medicinal purpose might imply a considerable hazard in Korea. In this study, using the established method for the detoxification from the stem bark of Rhus verniciflua, an strong antioxidant substance was isolated and characterized DPPH (diphenypricryl hydrazyl) assay measures hydrogen atom-donating activity and hence provides a measure of free radical scavenging antioxidant activity. DPPH, a purple-colored stable free radical, is reduced to yellow-colored diphenylpicryl hydrazine by antioxidants to deducing agents. Antioxidative effects of the water extract from RV were measured by DPPH assay. Twenty microliters of the extract was added to 1ml of 100mM DPPH solution in ethanol The mixture was shaken and left to stand for 10min at room temperature. The crude water extracts was purified by using HPLC method with a DEAE (anionic type), CN, ODS column. The purified compound remained stable at pH 3.0-6,0, but unstable above pH 6.5. It was stable heat at 10$0^{\circ}C$ for 4 hours, but still had about 80% of residual activity after treatment at 10$0^{\circ}C$ for 5 hours. The elemental composition of the HR-EI mass spectrum at m/z 170.02 was estimated the empirical formula as $C_{7}$ $H_{6}$ $O_{5}$. $C_{10}$ $H_4$ $O_2$N$_1$, $C_{5}$ $H_4$ $O_4$N$_3$, $C_{8}$$H_2O$$_1$N$_4$. In antimicrobial test, no inhibition was observed against Gram-positive and negative bacteria. This compound was stronger than that of commercial antioxidant by DPPH test, such as BHT, BHC at the same concentration (20$\mu$g/ml).ml).

• Journal of Microbiology and Biotechnology
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• 제15권4호
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• pp.909-912
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• 2005

In the course of screening for selective growth inhibitors against the mycelial form of Candida albicans, we isolated a Streptomyces sp. A6792 from soils. The inhibitor was isolated from the above bacterium and identified through several spectral analyses with UV and mass spectrophotometries, and various NMR. The compound was determined to be a macrocyclic dilactone antibiotic, IKD-8344 (molecular weight: 844, molecular formula: $C_{48}H_{76}O_{12}$). The compound selectively inhibited the growth of mycelial form of C. albicans with an MIC of 6.25 ${\mu}g/ml$. It also exhibited strong inhibitory effect preferentially on the mycelial form of various Candida spp. including C. krusei, C. tropicalis, and C. lusitaniae, with MICs ranging from 1.56 to 25 ${\mu}g$/ml. Furthermore, the compound showed no significant toxicity against SPF ICR mice up to 60 mg/kg. These results suggest that IKD-8344 is a useful lead compound for the development of novel antifungal agents, based on the preferential growth inhibition against Candida spp.

• 한국농림기상학회지
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• 제9권3호
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• pp.170-178
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• 2007

지난 수 세기 동안 온실기체와 기타 화학적으로 중요한 미량기체들이 급격하게 증가하였다. 이러한 주요기체가 기후 변화에 미치는 영향을 이해하기 위해서는 각 기체들의 흡원과 발원을 규명하고, 생물권과 대기권 사이에서 발생하는 생물 기원 기체 플럭스들을 특성화하며, 주요 기체를 조절하는 프로세스들을 이해해야 한다. 본 논문에서는 야외 실험을 위한 실용적 방법인 enclosure 기반의 관측법을 소개한다. 특히, 토양표면에서 방출되는 일산화질소 플럭스에 대한 enclosure내에서의 질량수지 방정식과 flow-through dynamic 플럭스 챔버 기법의 민감도를 제시하고 flow-through dynamic 플럭스 챔버 방법의 물리적인 시스템과 이론을 소개한다. 또한 챔버 벽에서 발생하는 일산화질소의 손실을 고려하므로써 새로운 플럭스 계산식을 소개하였고 그 계산식의 불확실성을 논의하였다.

• 조명전기설비학회논문지
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• 제27권6호
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• pp.95-99
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• 2013

Furnace is currently the most important doping process using POCl3 in solar cell. However furnace need an expensive equipment cost and it has to purge a poisonous gas. Moreover, furnace typically difficult appling for selective emitters. In this study, we developed a new atmospheric pressure plasma source, in this procedure, we research the atmospheric pressure plasma doping that dopant is phosphoric acid($H_3PO_4$). Metal tube injected Ar gas was inputted 5 kV of a low frequency(scores of kHz) induced inverter, so plasma discharged at metal tube. We used the P type silicon wafer of solar cell. We regulated phosphoric acid($H_3PO_4$) concentration on 10% and plasma treatment time is 90 s, 150 s, we experiment that plasma current is 70 mA. We check the doping depth that 287 nm at 90 s and 621 nm at 150 s. We analysis and measurement the doping profile by using SIMS(Secondary Ion Mass Spectroscopy). We calculate and grasp the sheet resistance using conventional sheet resistance formula, so there are 240 Ohm/sq at 90 s and 212 Ohm/sq at 150 s. We analysis oxygen and nitrogen profile of concentration compared with furnace to check the doped defect of atmosphere.

• Environmental Engineering Research
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• 제19권1호
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• pp.83-89
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• 2014

The effects of initial solid concentration and microwave irradiation (MWI) time on the hydrolysis of waste activated sludge (WAS) were investigated. MWI time strongly influenced WAS hydrolysis for all initial solid concentrations of 8.20, 31.51, and 52.88 g VSS/L. For all WAS, the volatile suspended solids (VSS) solubilization degree ranged from 35.6% to 38.4% during a total MWI time of 10 min. Soluble chemical oxygen demand (SCOD) concentration increased at a rate proportional to the decrease of VSS during the MWI. However, the clearly different VSS solubilization patterns that were observed during the MWI were explained by the 2-step hydrolysis of WAS, consisting of the initial disintegration of the easily degradable part of the sludge, followed by the subsequent disintegration of the hardly degradable part of the sludge. WAS hydrolysis rates for 3 to 6 min of MWI were significantly lower than those for less than 3 min, or more than 6 min. From these results, 3 min MWI time and WAS of 31.51 g VSS/L (centrifugal thickener WAS) showed the most efficient hydrolysis of WAS at 36.0%. The profiles of total nitrogen (T-N) concentrations corresponded well to the SCOD increases in terms of the empirical formula of bacterial cell mass ($C_5H_7O_2N$). The negligible T-N increase and pH decrease during WAS hydrolysis by MWI will allow the application of this process to subsequent biological processes, such as anaerobic digestion.

• The Korean Journal of Physiology
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• 제8권1호
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• pp.31-37
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• 1974

Formulas for the prediction of total body fat from skinfold thickness in middle aged men were presented. Hydrostatic weighing was made on 35 middle-aged men $(age:\;40{\sim}50\;years)$ sad corrected for residual volume in lung. Skinfold thickness at four sites, namely, arm, back, waist and abdomen were compared with total fat calculated from the formula given by Keys and Brozek and regression equations were derived. In middle-aged men the observed values were: Body density, 1.07478 ; total body fat, 10.51% body weight; lean body mass, 89.49% body weight; arm skinfold thickness, 4.85mm; back, 10.4 ; waist, 7.72; abdomen, 7.62 and mean skinfold thickness of the four sites, 7.59 mm. The correlations between skinfold thickness and body density were high. The correlations between skinfold thickness and total body fat were also high. The coefficient of correlation between total body fat and arm skinfold, mean skinfold thickness were r=0.839 and r=0.862, respectively. Arm and mean skinfold thicknesses (x, mm) could be used as the representative value for the prediction of total body fat (y, % body weight). The regression equations were: On arm y=2.00x+0.99, With mean skinfold y=1.20x+1.41 The coefficient of correlation between body weight (kg) and mean skinfold thickness was r=0.733. The ratio of mean skinfold thickness (mm) to body weight (kg) in middle-aged men was 0.132.

• Nutrition Research and Practice
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• 제14권4호
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• pp.352-364
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• 2020

BACKGROUND/OBJECTIVES: Given the increasing proportion of the Korean population that is aged 65 years and older, the present study analyzed the relationship between diet quality and sarcopenia in elderly persons by using data from the 2008-2011 Korea National Health and Nutrition Examination Survey (KNHANES). SUBJECTS/METHODS: Data for 3,373 persons aged 65 years and over (men: 1,455, 43.1%) were selected from the 2008-2011 KNHANES. Sarcopenia assessments are based on a formula that divides a subject's appendicular skeletal muscle mass (ASM) by their weight (wt) and multiplies that result by 100 ([ASM/wt] × 100). Sarcopenia is present if the subject's result was less than one standard deviation (SD) below the sex-specific mean for a young reference group. For evaluation of diet quality, data obtained via the 24-hour recall method were used to calculate the Diet Quality Index for Koreans (DQI-K). A general linear model was applied in order to analyze general information and nutritional intake according to sarcopenia status. For analysis of the relationship between diet quality and sarcopenia, a binominal logistic regression analysis was undertaken. RESULTS: The sarcopenia prevalence rate among the study subjects aged 65 years and over was 37.6%. The DQI-K of those without sarcopenia was 3.33 ± 0.04 points, while that of those with sarcopenia was 3.45 ± 0.04 points (P < 0.05). The relationship between diet quality and sarcopenia revealed that subjects aged 75 and older had a poor diet quality, and their odds ratio (OR) of sarcopenia presence was significantly higher (OR: 1.807, 95% confidence interval: 1.003-3.254, P < 0.05). CONCLUSIONS: This study revealed that poor diet quality was related to sarcopenia presence in Koreans aged 75 and older. In order to improve the diet quality of the elderly (aged 75 and older), it is necessary to develop dietary improvement guidelines.