• 상하수도학회지
• /
• 제18권5호
• /
• pp.638-648
• /
• 2004

In many drinking water treatment plants, chlorination process is one of the main techniques used for the disinfection of water. This disinfecting treatment leads to the formation of haloacetic acid (HAAs). In this study, headspace solid-phase microextraction (HS-SPME) was studied as a possible alternative to liquid-liquid extraction for the analysis of HAAs in drinking water. The method involves direct derivatization of the acids to their methyl esters without methyl tert-butyl ether (MTBE) extraction, followed by HS-SPME with a $2cm-50/30{\mu}m$ divinylbenzene/carboxen/polydimethylsiloxane fiber. The effects of experimental parameters such as selection of SPME fiber, the volume of sulphuric acid and methanol, derivatization temperature and time, the addition of salts, extraction temperature and time, and desorption time on the analysis were investigated. Analytical parameters such as linearity, repeatability and limit of detection were also evaluated. The $2cm-50/30{\mu}m$-divinylbenzene/carboxen/polydimethylsiloxane fiber, sulphuric acid of 1ml, methanol of 3ml, derivatization temperature of $50^{\circ}C$ derivatization time of 2hrs, sodium chloride salt of 10g, extraction time of 30 minutes, extraction temperature of $20^{\circ}C$ and desorption time of 1 minute at $260^{\circ}C$ were selected as the optimal experimental conditions for the analysis of HAAs. The linearities ($r^2$), relative standard deviations (%RSD) and limits of detection (LOD) for HAAs were 0.9978~0.9991, 1.1~9.8% and $0.05{\sim}0.2{\mu}g/l$, respectively.

• 분석과학
• /
• 제16권6호
• /
• pp.458-465
• /
• 2003

수용액 시료 중 휘발성 지방산을 HS (headspace)-SPME (Solid phase microextraction)를 이용하여 간편하고 빠르게 분석하는 방법에 대하여 연구하였다. 1-Pyrenyldiazomethane (PDAM)을 이용한 화이버 내 유도체화를 통하여 휘발성 지방산의 검출감도를 향상시킬 수 있었으며, SPME 추출조건으로 pH, 염 효과 및 초음파 추출에 대하여 조사하였다. 본 연구에서 개발된 방법을 기반으로 실제 폐수 중 휘발성 지방산을 추출하여 기체크로마토그래피/질량분석기-선택이온검색법으로 정량 분석하였다.

• 분석과학
• /
• 제17권6호
• /
• pp.527-531
• /
• 2004

Treatment with aqueous sodium hydroxide solution plays an important role to impart certain desirable properties - feel and luster on the surface of polyester fiber. In this process alkali wastewater contains disodium terephthalate, ethylene glycol (EG) and residual sodium hydroxide. In this paper we report a new method containing the pretreatments of derivatization with benzoyl chloride and solvent extraction using pentane. The calibration curve of EG determined by GC/MS-SIM shows a good linearity in the range of 0.1 to $25{\mu}g/mL$ having the standard deviation of ${\leq}8.7%$. The recovery and the detection limit of this method are 91.9-93.7% and $0.05{\mu}g/mL$ respectively.

• KSBB Journal
• /
• 제9권2호
• /
• pp.98-103
• /
• 1994

본 연구는 크로마토그래피적 방법에 의한 단백질 분리를 규모화시키기 위한 기초적인 실험을 행한 것이다. 단백질 분리를 위해서 화학적 처리된 폴리에틸렌섬유를 미국 Millipore사의 여과 Cartridge에 장착시키고, 그 시스템에서 단백질인 5%의 Bovine Serum Albumin을 통과시켜 섬유 표면의 단백질 흡착능력과 결합 가역성 등을 관찰하였다. 또한 실험자료들을 Omega 프로그램이 내장된 컴퓨터와 맥킨토시의 Kaleidagraph로 자료처리 한 것을 보여주었다.

• 한국초지조사료학회지
• /
• 제35권3호
• /
• pp.257-263
• /
• 2015

This study was conducted to assess the potential of using NIRS to accurately determine the chemical composition and fermentation parameters in fresh coarse sorghum and sudangrass silage. Near Infrared Spectroscopy (NIRS) has been increasingly used as a rapid and accurate method to analyze the quality of cereals and dried animal forage. However, silage analysis by NIRS has a limitation in analyzing dried and ground samples in farm-scale applications because the fermentative products are lost during the drying process. Fresh coarse silage samples were scanned at 1 nm intervals over the wavelength range of 680~2500 nm, and the optical data were obtained as log 1/Reflectance (log 1/R). The spectral data were regressed, using partial least squares (PLS) multivariate analysis in conjunction with first and second order derivatization, with a scatter correction procedure (standard normal variate and detrend (SNV&D)) to reduce the effect of extraneous noise. The optimum calibrations were selected on the basis of minimizing the standard error of cross validation (SECV). The results of this study showed that NIRS predicted the chemical constituents with a high degree of accuracy (i.e. the correlation coefficient of cross validation ($R^2{_{cv}}$) ranged from 0.86~0.96), except for crude ash which had an $R^2{_{cv}}$ of 0.68. Comparison of the mathematical treatments for raw spectra showed that the second-order derivatization procedure produced the best result for all the treatments, except for neutral detergent fiber (NDF). The best mathematical treatment for moisture, acid detergent fiber (ADF), crude protein (CP) and pH was 2,16,16 respectively while the best mathematical treatment for crude ash, lactic acid and total acid was 2,8,8 respectively. The calibrations of fermentation products produced poorer calibrations (RPD < 2.5) with acetic and butyric acid. The pH, lactic acid and total acids were predicted with considerable accuracy at $R^2{_{cv}}$ 0.72~0.77. This study indicated that NIRS calibrations based on fresh coarse sorghum and sudangrass silage spectra have the capability of assessing the forage quality control

• 대한화학회지
• /
• 제52권3호
• /
• pp.239-248
• /
• 2008

활성탄소섬유(ACF; activated carbon fiber)를 흡착제로 사용한 고상추출법(SPE; solid phase extraction)으로 수용액 시료 중에 존재하는 특정화학물질(schedule chemicals)의 분석법을 연구하였다. 본 연구에 사용된 특정화학물질은 화학작용제류의 가수분해 생성물과 유사작용제로 사용되는 알킬포스포네이트류, 티오디글리콜 등 14종이었다. 분석을 위한 추출물의 실릴 유도체화 반응에서 피리딘을 사용하여 특히 3-quinuclidinol의 유도체화 반응 효율을 높일 수 있었다. 물 시료에서 아민류의 추출 회수율을 개선하기 위하여 SPE-ACF 튜브에 시료를 부하하기 전에 5% triethylamine/MeOH(1 mL) 용액으로 SPE-ACF 튜브를 세척한 후에 시료를 SPE-ACF에 부하하는 방법으로 추출 회수율을 증대시킬 수 있었다. 이 연구를 통해서 수용액 시료에서 특정화학물질을 신속히 검출할 수 있는 최적 조건을 선정하였다.

• Safety and Health at Work
• /
• 제9권4호
• /
• pp.479-485
• /
• 2018

The aim of this study is to validate an integrated air monitoring approach for assessing airborne formaldehyde (FA) in the workplace. An active sampling by silica gel impregnated with 2,4-dinitrophenylhydrazine, a passive solid phase microextraction technique using O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine as on-fiber derivatization reagent, an electrochemical direct-reading monitor, and an enzyme-based badge were evaluated and tested over a range of 0.020-5.12 ppm, using dynamically generated FA air concentrations. Simple linear regression analysis showed the four methods were suitable for evaluating airborne FA. Personal and area samplings in 12 anatomy pathology departments showed that the international occupational exposure limits in the GESTIS database were frequently exceeded. This monitoring approach would allow a fast, easy-to-use, and economical evaluation of both current work practices and eventual changes made to reduce FA vapor concentrations.