• Analytical Science and Technology
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• v.24 no.2
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• pp.142-149
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• 2011

This study was conducted to define metabolite of the resveratrol by gas chromatography- time-offlight mass spectrometric detection. From these results, we suppose that the structure of metabolite is the result of reduction of double-bond attached by two-phenyl groups. Also, validity of method for determining metabolite of resveratrol and endogenous steroids was tested. The recoveries ranged from 96.47 to 114.74%, and intraand inter-day precision ranged 11.40 - 10.87% and 1.10 - 10.93%, accuracy ranged 80.03 - 119.92% and 80.02 - 119.56%, respectively. Resveratrol and endogenous steroids had correlation coefficients above or equal to 0.996. The method was successfully validated for the determination of resveratrol and endogenous steroids. Urinary samples from volunteers dosed resveratrol were analyzed to confirm a correlation resveratrol and its metabolite. From these results, the highest level of resveratrol and its metabolite was excreted in 10 - 15 hr more slowly than common drug, and conversion rate of metabolite was higher in woman than that in man. In addition, endogenous steroids were shown same the highest level of 10 - 15 hr. For estrone and estradiol, sensitivity was relatively higher in female than in man. And there were no significant changes of excretion patterns in the other endogenous steroids. Thus, we assumed that activation of resveratrol has impact on woman than man.

• Analytical Science and Technology
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• v.15 no.2
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• pp.127-134
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• 2002

Analytical method to determine rare earth elements which were extracted to organic phase by inductively coupled plasma mass spectrometry(ICP-MS) was investigated. Organic phase which had extracted rare earth elements was directly aspirated into ICP-MS by ultrasonic nebulizer(USN) in order to reduce solvent load to the plasma. Then, the count rate increased when MIBK(methyl isobutyl ketone) was added to EtOH(ethanol) but decreased when 0.03 M HEH(2-ethylhexyl-2-ethylhexyl phosphonic acid, $P_{507}$, PC88A) was added to solvent which mixed MIBK with EtOH. The optimal temperatures of desolvation system were -10 $^{\circ}C$ for the condenser and 150 $^{\circ}C$ for the heating tube. The optimal nebulizer flow rate which gave maximum count rate and minimum reflect power was 0.7 L/min. The optimal pH and extraction time were 4.3 and 10 min for MIBK-0.03 M HEH system. Detection limits which were obtained through calibration curves at the range of 0.2 ${\sim}$ 20 ng/mL were 0.02 ${\sim}$ 0.05 ng/mL under the optimal experimental conditions.

• Proceedings of the ESK Conference
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• 1994.04a
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• pp.157-157
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• 1994

원자력발전소 운영의 중추적 역할을 담당하고 있는 운전원과 발전소시스템 사이에서 발생하는 인간공학적 요인(인적요인)은 다중방호벽의 존재와 자동화 기술의 확대에도 불구하고 원전의 가동 성 및 안전성을 위협하는 최대의 요인이다. 최근 원자력발전소 시스템에 고도화된 전자공학 및 인공 지능기술 등이 반영되고 있는 추세이나 이러한 기술의 도입이 운전원과의 복합적 상호작용관점에서 원전의 안전성과 효율성에 적합한가를 실험적으로 평가할 수 있는 실험평가기술의 확보가 필요한 실정이다. 한국원자력연구소에서는 차세대 주제어실의 설계 및 평가를 위한 실험적 자료의 생성 및 설계 대안의 평가를 위한 기술확보라는 목적을 가지고 1992년도부터 수행하고 있다. 1992년도(1차년 도)에는 새로운 주제어실에서 실험적으로 평가해야 할 평가항목을 구체화하였고, 4년간의 연구추진 내용을 설정하였다. 기존의 원자력산업계에서 요구하고 있는 인가/허가 요건, 사업자요건서, 인간 공학분야에서 제기하고 있는 문제점 등을 분석하여 10개의 실험평가항목을 도출하였으며, 실험평가 항목을 실제로 실험을 통하여 연구하기 위한 장비 및 설비 그리고 소요기술 등을 고려하여 연구방향을 설정하였다. 1993년도(2차년도)에는 차세대 주제어실의 특징을 규명하고 실험연구의 대상시스템을 설정하였다. 설정된 대상시스템을 기능별로 분석하여 설계변수를 도출하였으며, 인간공학 실험실의 구축에 필수적인 원자력발전소 시뮬레이터의 기능요건 및 실험실의 구성요건 등을 개발하고 있다. 3차년도부터는 인간공학실험을 수행하면서 자료분석체계의 개발, 원전직무 시나리오의 개발, 측정방법의 개발, 인간공학 실험실의 설계, 구축 및 검증, 평가기법 연구, 실시간 자료수집체계의 개발 등을 수행할 예정이며, 연구종료시점인 1996년도(5차년도)에는 원자력발전소 주제어실의 인간공학적 평가를 위한 실험 환경의 구축 및 실험평가기술의 확립이라는 목표가 달성된다.하는 것으로 간주된다. 2. KR 53234 10mg/kg 정맥투여후의 최고혈중농도는 1.14ug/ml, 반감기는 0.50hr, 분포용적은 2.2L이었다. 20mg/kg 경구 투여시의 최소 혈중 농도는 0.33 ug/ml, 소실반감기는 1.5시간, AUC는 0.942ug.hr/ml, 분포용적 11L, Ka는 3.05 $hr^{－1}$ 그리고 Cl는 5.3L/hr/kg이었다. 이는 KR 53170에서와 같이 매우 적은량이 흡수되고 배설되었다. 3. KR 53170의 혈청단백 결합율은 5-500 ug/ml 범위에서 78.7-86.2%이었고 KR 53234의 혈청단백결합율은 5-100 ug/ml 범위에서 79.6-71.2%이었다.이었다.tic techniques, and we have recently cloned two of the major subunits; some of the data will be presented.LIFO, 우선 순위 방식등을 선택할 수 있도록 확장하였다. SIMPLE는 자료구조 및 프로그램이 공개되어 있으므로 프로그래머가 원하는 기능을 쉽게 추가할 수 있는 장점도 있다. 아울러 SMPLE에서 새로이 추가된 자료구조와 함수 및 설비제어 방식등을 활용하여 실제 중형급 시스템에 대한 시뮬레이션 구현과 시스템 분석의 예를 보인다._3$", chain segment, with the activation energy of carriers from the shallow trap with 0.4[eV], in he amorphous regions.의 증발산율은 우기의 기상자료를 이용하여 구한 결과 0.05 - 0.10 mm/hr 의 범위로서 이로 인한 강우손실량은 큰 의미가 없음을 알았다.재발이 나타난 3례의 환자를 제외한 9례 (75%)에서는 현재까지 재발소견을 보이지 않고 있다. 이러한 결과는 다른 보고자들과 유사한 결과를 보이고 있

• Elastomers and Composites
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• v.38 no.3
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• pp.227-234
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• 2003

Silicone composites for high voltage insulator (HVI SC) were prepared by adding aluminum trihydrate(ATH) treated by surface treatment agent to base silicone compound at the ratio oi 100:20, 100:40, 100:60, 100:80, and 100:100, respectively And also, ATH was treated by various surface treatment agents, such as stearic arid, acryl silane, and vinyl silane under compounding process. Mechanical properties and electrical properties were investigated for the various contents of ATH and surface-treatment agents. Mechanical properties such as tensile strength, elongation, and tear strength decreased as the load of ATH increased. Volume resistivity, AC break down strength, and tracking resistance for HVI SC containing ATH treated by vinyl silane were better than those for HVI SC containing ATH treated by other surface treatment agents, such as stearic acid and acryl silane. Polymer-filler interaction of silicone composites according to surface treatment agents was studied by measuring bound rubber contend(BR). From the experimental results, BR of silicone composite containing ATH treated with vinyl silane was higher than that of the others. The degree of rule for silicone composite was investigated using Rheometer. Maximum torque of silicone composites contaning ATH treated with vinyl silane was higher than that of silicone composite contaning ATH treated with other surface agents.

• Journal of the Korean Wood Science and Technology
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• v.43 no.3
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• pp.344-354
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• 2015

To investigate the effects of ionic liquid pretreatment on biomass, giant miscanthus was treated with 1-ethyl-3-methylimidazolium acetate ([Emim][OAc]) and 1-butyl-3-methylimidazolium acetate ([Bmim][OAc]) at three temperature conditions ($90^{\circ}C$, $110^{\circ}C$, and $130^{\circ}C$). As temperature condition increased, yield of the cellulose-rich product (CP) was reduced from 87.2% to 67.6%, while yield of the ionic liquid lignin (ILL) increased from 2.2% to 9.9%. Compared to the ILL, CP had lower carbon contents and higher oxygen contents. Enzymatic hydrolysis of CPs showed that conversion ratio of CP treated with [Emim][OAc] at $110^{\circ}C$ was 56.7%, the highest digestibility. Thermogravimetric analysis indicated that the maximum degradation rate decreased as temperature condition increased. In addition, maximum degradation temperature of ILL treated with [Emim][OAc] ranged from 274 to $279^{\circ}C$ which was lower than that of ILL treated with [Bmim][OAc]. Analytical date for ${\beta}$-O-4 linkage frequency in the ILL revealed that ${\beta}$-O-4 linkage frequency in the ILL decreased as the temperature rose. Furthermore, the highest S/G ratio of the ILL was determined to ca. 1.2 obtained from [Bmim][OAc] treatment at $110^{\circ}C$.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.3
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• pp.119-126
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• 2019

In case of RC(Reinforced Concrete) structures which are constructed in coastal areas, chloride ions in sea water corrode the steel rebar in concrete. Especially in coastal areas, RC structures are affected by not only immersion of sea water, but also tidal of sea water and airborne chloride ions. In this study, marine environment exposure tests are conducted, considering 3 types of exposure environments(immersion zone, tidal zone, splash zone) and the exposure periods of 180 days, 365 days, and 730 days. Also, the concrete mixtures for this study are established, considering 3 levels of W/B(Water to Binder) ratio(0.37, 0.42, 0.47) and 2 levels of substitution rate of Fly ash(0 %, 30 %). In all exposure environments, Fly ash concrete has lower apparent chloride diffusion coefficients than OPC concrete. It is thought that fly ash's pozzolan reaction improves chloride resistance of concrete. Fly ash concrete has up to 63.5 % of decreasing rate in 180 days of exposure and up to 55.8 % of decreasing rate in 730 days of exposure, based on diffusion coefficients of OPC concrete. As a result of evaluation about effects of exposure environments, apparent chloride diffusion coefficients of fly ash concrete are evaluated in order of tidal zone, immersion zone, and splash zone. In tidal zone, It is thought that repeated cycles of wetting and drying of sea water cause the diffusion of chloride ions rapidly.

• The Journal of Engineering Geology
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• v.28 no.1
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• pp.11-24
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• 2018

The purpose of slope stability analysis is to predict the location and occurrence time considering the rainfall, topographic and soil characteristics, etc. In this study, infinite slope stability analysis considering the time distribution characteristics of the daily maximum rainfall was conducted using a model that combines a digital terrain model and a groundwater flow model. As the results of slope stability analysis, 69.1~70.0% of Fs < 1 cells are in the range of slope angle $20{\sim}50^{\circ}$ and Fs < 1 starts to appear in 2 hours for $Q_1$ model, 5 hours for $Q_2$, 7 hours for $Q_3$ and 6 hours for $Q_4$. Furthermore, the maximum number of Fs < 1 cells appear in 6 hours for $Q_1$ model, 12 hours for $Q_2$, 16 hours for $Q_3$ and 20 hours for $Q_4$, and the area of Fs < 1 is 14.3% for $Q_1$ model, 15.0% for $Q_2$, 15.6% for $Q_3$, and 16.3% for $Q_4$.

• The Korean Journal of Nuclear Medicine Technology
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• v.22 no.1
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• pp.23-27
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• 2018

Purpose The introduction of bone scan has been reported as a useful tool in the diagnosis, treatment, and treatment response of skeletal disease. The purpose of this study is to improve the anatomical information and tolerance of the bone by combining bone scan and pelvic X-ray without additional radiation exposure. Materials and Methods From November 2015 to August 2016, 236 patients(64 men and 172 women, average age $50.96{\pm}15.39years$) take Bone scan and Pelvis AP(Anteroposterior) X-ray scan at the National Cancer Center. The scan equipment was a gamma camera, Symbia Ecam (SIEMENS, Germany), and a digital x-ray, DRS-800 (Listem, Korea). Osirix version 3.8.1 (Osirix, USA) and Stata/SE version 14.0 (StataCorp, USA) were used for image combination and analysis. The patient was intravenously injected with $^{99m}Tc-DPD$ (740 MBq), and the scan was performed 2 to 4 hours later. Gamma camera image acquisition were Matrix size $256{\times}1024$, Zoom 1.00, and scan speed 17 cm/min. The digital X-ray was made with a collimator size of $14^{{\prime}{\prime}}{\times}17^{{\prime}{\prime}}$, 77 kVp (60 to 97 kVp) and an average of 30 mAs (20 to 48). ASIS and pubic symphysis Select virtual points then Combine three virtual points and pelvic contour lines. The acquired images were evaluated by three radiologists who worked for more than 5 years in the nuclear medicine department. Results Of the total 236 patients, 216 (91.53%) were matched. The median and range (min~max) of the age were 67 (46~81) years old in the unmatched group and 52 (22~87) years old in the matched group, The Wilcoxon rank-sum test was performed to determine whether age was different between the two groups. As a result, the age difference between the two groups was statistically significant at p < 0.0001. Of the 64 men, 60 (93.75%) were match and of the 172 women, 156 (93.75%) were match. There was no statistically significant difference according to gender(p = 0.4542). Of the 54 patients without pelvic lesions, 54 (100.00%) were match, and 162 (89.01%) of 182 patients with pelvic lesions were match. There was a statistically significant difference according to the presence of pelvic lesions. Conclusion There are many variables in the combination of bone scan and pelvic X-ray imaging, and the patient's age and pelvic lesion may have some effect on the image combination. This study is expected to be useful for the diagnosis of pelvic osteosarcoma of children without radiation exposure. It is expected that this combination of images will help to develop the nuclear medicine image.

• The Journal of Engineering Geology
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• v.20 no.1
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• pp.47-60
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• 2010

This study is focused on the analysis of tunnel behavior to estimate the stability on tunnel design. An estimation method was proposed as a hybrid consideration, which contains the displacement analysis by 3D numerical simulation, the maximum displacement obtained after field measurement, and an assessment of tunnel stability using a deformation analysis proposed by Sakurai(1988, 1997). The points of case study by Sakurai(1988, 1997) were replotted considering his analysis. From the new analysis of the tunnel case study, the trend line for analyzed points is analogized, which curve is divided into stable, unstable and failure zone. To evaluate the estimation method, a special shape of railway tunnel was selected, which are the Inchon international airport rail way connected to subway line 9 in Gimpo, Korea. The point s of upper and below track on the Inchon international airport rail way were satisfied to the stability of tunnel after reinforcing. Also the points shows the higher apparent Young's modulus, which resulted from improvement on shear strength by the micro silica grouting and the supporting of umbrella method. Therefore, if new analysis used, proper tunnel reinforcing method could be selected according to tunnel strain and geological property.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4B
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• pp.441-447
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• 2008

Volatile organic compounds (VOCs) emitted from various industrial sources commonly consist of biodegradable chemicals and recalcitrant compounds. Therefore, it is not effective to employ a single method to treat such mixtures. In this study, a novel hybrid system coupled with a ultraviolet (UV) photolysis reactor and a biofilter in a series was developed and evaluated using toluene and TCE as model VOCs. When only TCE was applied to the UV reactor, greater than 99% of TCE was degraded and the concentration of soluble byproducts from photo-oxidation reaction increased significantly. However, the toluene and TCE mixture was not effectively degraded by the UV photo-oxidation standalone process. The hybrid system showed high toluene removal efficiencies, and TCE degradation at a low toluene/TCE ratio was improved by UV pretreatment. These findings indicated that the UV photo-oxidation were effective for TCE degradation when the concentration of toluene in the mixture was relatively low. A restively high toluene content in the mixture resulted in an inhibition of TCE degradation. Thus, chemical interactions in both photo-oxidation and biodegradation need to be carefully considered to enhance overall performance of the hybrid system.