• 분석과학
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• 제19권2호
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• pp.155-162
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• 2006

본 연구에서는 잔류농약을 효과적으로 제거하는 방법을 토양 및 수용액상에서 연구하였다. 이를 위해 표준물질은 유기염소계 ${\alpha}$-endosulfan, ${\beta}$-endosulfan을 사용하였다. 분석방법은 각각 채취한 시료를 전처리하여 Ultra II[$(30m{\times}0.25mm(ID){\times}0.25{\mu}m$] 컬럼을 장착한 GC-${\mu}$-electron capture detector(${\mu}$-ECD)로 분석하였다. 토양 중 잔류농약의 회수율은 96-100%로 나타났다. 토양에 농약분해제를 살포하여 시간별 ${\alpha}$-endosulfan, ${\beta}$-endosulfan의 변화량을 분석한 결과 73, 61% 감소하였다. 토양시료에 농약분해제를 첨가하고, 수분의 양을 10 mL에서 100 mL로 증가 시키면서, 잔류농약의 변화량을 측정하였다. 그 결과, ${\alpha}$-endosulfan은 45%에서 85 %로, ${\beta}$-endosulfan은 44%에서 88%로 제거되었다. 마지막으로, 수용액상에서도 시간별 endosulfan의 제거율 실험을 하였다. 실험 결과 30분 내에서 ${\alpha}$-endosulfan은 99%, ${\beta}$-endosulfan은 98%가 분해 제거되었다. 이와 같은 현상은 농약분해제에 많은 유기산염과 강알칼리 성분들이 알칼리 가수분해를 일으킨 것으로 추정할 수 있다.

• 한국식품과학회지
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• 제39권2호
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• pp.114-121
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• 2007

서울지역에 유통되고 있는 국내산 및 수입산 건조농산물 58건을 대상으로 다성분 동시분석방법에 따라 GC-NPD, $GC-{\mu}ECD$, HPLC-UV와 HPLC-FLD로 분석가능한 총 253종의 농약잔류량을 분석한 후 GC-MSD로 확인한 결과 총 14건의 건조농산물에서 잔류농약이 검출되어 24.1%의 검출률을 나타내었고, 이 중 건조 채소류의 검출률은 25.5%였다. 품목별 잔류농약의 검출률은 건조과채류, 건조엽채류, 건조엽경채류 순으로 높았으며, 특히 건조 과채류 중 건조고추의 잔류농약 분포가 다양하고 검출빈도가 상당히 높았다. 건조 농산물의 기준에 없는 12종의 잔류농약이 검출되었으며, 합성피레스로이드계, 유기염소계, 유기인계 순으로 검출빈도가 높았고, 특히 합성피레스로이드계 중 cypermethrin의 검출 횟수가 가장 많았다. 또한 대상목적에 따라 분류하면, 살충제, 살균제, 제초제, 살선충제 순서로 검출건수가 많았다. 산지별로 보면, 국내산, 중국산 ,북한산, 미국산, 베트남산의 순서로 잔류농약의 검출건수가 많았으며, 국내산은 과채류에서 수입산은 엽경채류에서 잔류농약의 검출빈도가 높았다.

• Archives of Pharmacal Research
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• 제21권6호
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• pp.698-702
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• 1998

Propentofylline (PPF, 3-methyl-1-(5-oxohexyl)-7-propylxanthine) has been reported to be effective for the treatment of both vascular dementia and dementia of the Alzheimer type. The pharmacological effects of PPF may be exerted via the stimulation of nerve growth factor, increased cerebral blood flow, and inhibition of adenosine uptake. The objectives of this experiment are to determine the kinetic behavior of PPF, to identify, and to quantify its metabolite in human. Blood samples were obtained from human volunteers following oral administration of 200mg of PPF tablets. For the identification and quantification of the metabolite, 3-methyl-1-(5-hydroxyhexyl)-7-propylxanthine (PPFOH), PPFOH was synthesized and identified by gas chromatography/mass spectroscopy (GC/MS) and $^1H$-nuclear magnetic resonance spectroscopy. The molecular weight of synthesized metabolite is 308 dalton. The PPF and PPFOH in plasma were extracted with diethyl ether and identified by electron impact GC/MS. The plasma concentrations of PPF and PPFOH were determined by gas chromatography/nitrogen phosphorus detector in plasma and their pharmacokinetic parameters were determined. The mean half-life of PPF was 0.74 hr. The areas under the curve (AUCs) of PPF and PPFOH were 508 and 460ng.hr/ml, respectively. $C_{max}$ of PPF was about 828.4ng/ml and the peak concentration was achieved at about 2.2 hr ($T_{max}$). These results indicate that PPF is rapidly disappeared from blood due to extensive metabolism into PPFOH.

• 한국환경농학회지
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• 제35권3호
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• pp.211-215
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• 2016

BACKGROUND: The commercial biopesticides containing Chenopodium ambrosioides L. extracts which have been registered as one of the ingredients of the commercial biopesticide by the organic agriculture materials, and have been widely used in Republic of Korea. However, the quantitative analysis method of the active substances for the commercial biopesticides containing C. ambrosioides L. extract has not been conducted.METHODS AND RESULTS: To analyze the quantitative analysis of ascaridole, carvacrol, and p-cymene as active substances of C. ambrosioides L. extract, hydrophilic lipophilic balance cartridge was used for solid phase extraction. The active substances were analyzed by the gas chromatography with flame ionization detector. The limit of quantitation values of ascaridole, carvacrol, and p-cymene were 10, 5, and 2 mg/L, and the recovery rates were 96.3, 84.0, and 82.5% in liquid products and 98.3, 99.1, and 97.3% in solid products, respectively. The total content of ascaridole, carvacrol, and p-cymene in the commercial biopesticides was ranged from 0.08 to 12.75%.CONCLUSION: From these results, this method was suitable for the quantitative analysis of the active substances of commercial biopesticides containing C. ambrosioides L. extract.

• 한국축산식품학회지
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• 제33권5호
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• pp.672-677
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• 2013

The aim of this study was to develop sample preparation method and evaluate the exact cholesterol content in egg and egg powder purchased from Korean markets, and to determine whether significant differences exist among various egg products, since a variety of products are available in Korean markets and there are no recent databases for cholesterol. To evaluate the cholesterol content in chicken egg sold in Korean local market, a simple method using non-heated saponification to determine cholesterol for emulsified foods was applied. The results of recovery for egg and egg powder were in a range of 92.4-105.0%, with a relative standard deviation between 1.1% and 2.8% by using gas chromatography-flame ionization detector. Therefore, the total cholesterol content in whole egg was estimated between 160.8 and 226.3 mg/egg (AV(average) $186.8{\pm}3.5$), which is similar or lower than previously reported levels. The value for cholesterol in egg powder was estimated between 2.94 and 3.49 mg/g (AV $3.23{\pm}0.15$). We suggested method that can be applicable to chicken egg and egg powder matrix as providing rapid and accurate determination of cholesterol in egg and egg powder. This information will be helpful for processed food producers for deciding food labels of cholesterol content.

• 한국가스학회지
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• 제9권3호
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• pp.1-8
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• 2005

배관은 사용기간 중에 여러 가지 열화에 의해 손상을 받으며, 그 중 감육(두께감소)이 발생하게 되면 심각한 결과를 초래할 수 있다. 따라서, 배관시스템의 보전유지를 위해서는 감육되어진 배관의 강도를 평가하는 것이 중요하다. 어떤 재료가 외부 응력 등에 의해 파괴 혹은 변형된다면 그 특징적인 탄성파가 변형메카니즘에 따라 여러 가지로 다르게 나타날 수 있다. 본 연구에서는 감육을 가지는 배관에서 감육결함의 길이 및 깊이를 다르게 상정하였을 때 나타나는 AE신호들에 대해 Wavelet Transform시스템을 이용하여 평가하였다. 또한,실배관의 굽힘시험을 통하여 기계적인 강도를 평가하였다. 결과로부터, 감육의 깊이비(d/t)의 정도에 따라 주파수 성분을 구별하는 것이 가능하였다.

• 한국환경과학회지
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• 제22권12호
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• pp.1539-1549
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• 2013

The purpose of this study is to compare the sampling methods for monitoring indoles (phenol, p-cresol, indole and skatole) in airs of swine facility. As the collecting methods of indoles in air, Tenax-TA adsorption tube and solid phase microextraction (SPME) were examined. For the preparation of calibration curves of indoles concentrated in Tenax-TA, the standard indoles solutions were spiked in each of Tenax-TA tubes and thermally desorbed (ATD) into a gas chromatograph combined with mass detector (GC/MS). And for the preparation of calibration curves by SPME, indoles in the standard gaseous solution prepared by evaporating the aqueous solution that contained indoles into a polyester sampling bag were extracted with SPME fiber and subsequently analyzed by the GC/MS. Two sampling methods were evaluated for extracting indoles present in swine building environments. Results indicated that the SPME method using Polydimethylsiloxane/ Divinylbenzene (PDMS/DVB) fiber was more effective than Tenax-TA method in extracting indoles. The gas chromatographic analysis showed that the linearities of calibration curves and detection limits were useful for detection of indoles in swine airs. The field tests also showed that considerably different levels of indoles were present in various parts of the swine building.

• 한국산업보건학회지
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• 제3권1호
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• pp.37-53
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• 1993

The polynuclear hydrocarbons (PAHs) emitted from coke oven standpipe were sampled using three sampling systems, including glass fiber filter+silver membrane filter, glass fiber filter+silver membrane filter+XAD-2 adsorbent tube, PTFE membrane filter+XAD-2 adsorbent tube, extracted by methylene chloride and analysed by gas chromathography using flame ionization detector. The results of this study were as follows. 1. Because the amounts of coke oven emissions(COE) were large, the analyses of PAHs were simple and possible without evaporation and concentration. Although the generation of COE was high during early stage of coking, the airborne concentration of PAHs was low and increased during late coking. 2. The contents of PAHs in COE were 1.35-2.81%. 3. The index components of PAHs were fluoranthene and pyrene. Their correlation coefficient to total PAHs were 0.96, 0.95, respectively. 4. The particulate PAHs were sampled by filter and gaseous PAHs by adsorbent tube. The collection efficiency of glass fiber filter+silver membrane filter was 20% of total amount sampled by filters+adsorbent and PTFE membrane filter 50%. Adsorbent tube must be attached to the filter to collect light and small PAH components. 5. The generation of acenaphthene and indeno (1,2,3-cd) pyrene were low and concentrations of fluorene and anthracene were $20-40ug/m^3$ throughout coking time. Other PAH eoncentrations were sometimes high. The generation of PAHs was low at 4-6 hours of coking time. The gaseous PAHs were generated earlier than particulate PAHs.

• 한국대기환경학회지
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• 제19권5호
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• pp.529-540
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• 2003

A closed chamber system was used for measuring $N_2$0 fluxes from an agriculturally managed upland soil in Kunsan during the growing season from May to July 2002. It is known that soil is one dominant source of atmospheric $N_2$O, contributing to about 57% (9 Tg y $^{-1}$ ) of the total annual global emission. Hence, its increasing emissions and concentrations are largely associated with agricultural activities. In order to elucidate characteristics of soil nitrogen emissions from intensively managed agricultural soils and to understand the roles of soil parameters (soil moisture, soil pH, soil temperature, and soil nitrogen) in the gas emission, $N_2$O soil emissions were measured at every hour during the experimental period (21 days). Soil $N_2$O fluxes were calculated based on changes of $N_2$O concentrations measured inside a closed chamber at every hour. The analysis of $N_2$O was made by using a Gas Chromatography (equipped with Electron Capture Detector). Soil parameters at sampling plots were also analyzed. Monthly averaged $N_2$O fluxes during May, June, and July were 0.14, 0.05, and 0.13 mg-$N_2$O m$^{-2}$ h$^{-1}$ , respectively. Soil temperature and soil pH did not significantly vary over the experimental period; soil temperatures ranged from 12∼$25^{\circ}C$, and soil pH ranged 4.56∼4.75. However, soil moisture varied significantly from 32% to 56% in WFPS. Relationships between soil parameters and $N_2$O fluxes exhibited positive linear relationships. Strong positive correlation ($R^2$ = 0.57, P< 0.0001) was found between $N_2$O flux and sil moisture. It suggests that soil moisture has affected strongly soil $N_2$O emissions during the experimental periods, while other parameters have remained relatively at constant levels. $N_2$O flux from agricultural soils was significant and should be taken account for the national emission inventory.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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• pp.201-205
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• 2007

본 논문은 휴대폰의 무선 인터넷 플랫폼 어플리케이션을 통해 화재 및 가스누출 등 각종 위험을 통보해 주는 지능형 홈서비스 로봇을 구현하였다. 지능형 홈서비스 로봇은 세 가지 구성요소(로봇부, 미들웨어부, 모바일부)로 이루어진다. 로봇부는 가스센서, 불꽃 감지센서, 연기 센서, 초음파 센서, 모터, 카메라, 블루투스 모듈로 구성되며, 각종 위급 상항을 감지한다. 미들웨어부는 미들웨어 어플리케이션을 통해 로봇부와 모바일부를 연결하고, 로봇을 모니터링하며 SMS모듈을 이용하여 응급상황을 통지한다. 모바일부는 TCP/IP 프로토콜을 이용하여 미들웨어부와 통신하며 로봇에 각종 명령을 내려주고 행동을 제어한다. 제안된 방식은 Atmega128 프로세서를 통하여 로봇부의 각종 센서를 제어하며, 모바일부는 WIPI 플랫폼 기반으로 개발하였다. 로봇부와 미들웨어부는 가정에 설치되며 외부에서 모바일부를 통하여 제어된다.