• Journal of Korean Society for Atmospheric Environment
• /
• v.18 no.2
• /
• pp.127-137
• /
• 2002

Phenolic compounds in air are toxic even at their low concentrations. We had evaluated a total of five phenolic compounds (Phenol, o-Cresol, m-Cresol, 2-Nitrophenol and 4-Chloro-3-methylphenol) in artificial air using a combination of ATD/GC/MS. To compare the adsorption efficiency of these phenolic compounds, three adsorbents (Tenax TA, Carbotrap and Carbopack B) were tested. Tenax TA adsorbent was most effective of all the adsorbents used for the efficiency test. Five phenolic compounds were found to be very stable on adsorbent tubes for 4 days at room temperature. Detection limit of five phenolic compounds ranged from 0.05 to 0.08 ppb (when assumed to collect 10 L air). The calibration curve was linear over the range of 22∼ 164 ng. The reproducibility was less than 4%. Sampling of duplicate pairs (DPs) was made to demonstrate duplicate precision and sampling efficiency.

• Korean Journal of Food Science and Technology
• /
• v.30 no.6
• /
• pp.1247-1251
• /
• 1998

A method is developed for simultaneously determining ethanol and acetic acid in vinegars by quantitative packed-column gas chromatography. Vinegars were filtrated and directly chromatographed on a $2\;m{\times}2\;mm$ stainless steel column packed with Tenax-GC, 80/100. Ethanol, isopropy alcohol as an internal standard, and acetic acid were completely separated within 20 min of running time without any interfering peaks. The accuracy of packed column gas solid chromatography (PCGSC) was discussed compared to the analytical data by titration, high performance liquid chromatography and capillary column gas liquid chromatography (CCGLC).

• Journal of the Society of Disaster Information
• /
• v.9 no.3
• /
• pp.249-258
• /
• 2013

Recieved Mar. 06, 2013 Revised Mar. 29, 2013 Accepted Sep. 11, 2013In this study, we evaluated the method performance and the optimum sample injection method of the portable GC/MS(HAPSITE) which were designed to operate on scene of chemical accidents. Chemicals used for performance test were vinyl chloride(VC), methyl chloride(MC), benzene(Bz), toluene(Tol). CRM(Certified Reference Material) Manufactured by KRISS(Korea Research Institute of Standards and Science) was used as the standard gas. The results showed that 1) Among three sample injection methods(Cylinder, Silico canister, and Bag), bag was identified as the most appropriate sample injection method. Bag material and capacity did not significantly affect the results. The most ideal reproducibility occurred at the 2-minute point of the purge time in the loop and tenax methods. 2) Performance evaluation of HAPSITE was conducted. Evaluation items were reproducibility, linearity, method detection limit, etc. Tenax concentration method was appropriate for larger molecules and Carbopack concentration method was suitable for smaller molecules.

• Journal of Korean Society for Atmospheric Environment
• /
• v.25 no.6
• /
• pp.523-538
• /
• 2009

Recently, there has been a keen demand for real-time automatic monitoring of VOCs not only in Korea but other developed countries. We carried out this study to evaluate and to optimize the performance of a continuous automatic monitoring system for hazardous VOCs (HVOCs) in the ambient atmosphere, using an on-line GC system. The online system normally consisted of a Nafion dryer prior to a cold trap of an automatic thermal desorption apparatus and a GC system equipped with two detectors, i.e. PID and ECD. Preliminary tests conducted to check out any contamination of the system revealed an evidence of significant artifact formation of benzene, and it was found that the Nafion dryer (even brand new one) is the source of the benzene artifact. Thus, all the subsequent experiments in this study was carried out inevitably by removing the Nafion dryer. The on-line GC method was investigated with a variety of QC/QA performance criteria such as repeatability, linearity, lower detection limits, and accuracy. In order to find out the best operating condition for the on-line GC system, three different types (in terms of adsorption strength) of cold trap combinations were tested, i.e. (i) Tenax-TA and Carbopack-B combination (weak and hydrophobic); (ii) Tenax-TA, Carbopack-X and Carboxen-1000 combination (strong and hydrophilic); and (iii) Tenax-TA and Carbopack-X combination (medium and hydrophobic/hydrophilic). The USEPA TO-17 manual method was selected as a reference method to evaluate the performance of the on-line method. A series of experiments revealed that the system performance was superior to others when a cold trap packed with hydrophilic adsorbents (Tenax-TA/Carbopack-X/Carboxen-1000 combination) was used and operated at $25^{\circ}C$. However, the system with a cold trap packed with a combination of Tenax-TA and Carbopack-X is more recommended for field applications since the carboxen-1000 adsorbent is too sensitive to water vapor, and hence the performance of the system might be very unstable to humid samples or during rainy days. Furthermore, the precision and accuracy criteria of the Tenax-TA/ Carbopack-X combination were generally compatible with the triple adsorbents cold trap. The continuous automatic monitoring method is, thus, considered very useful to real-time monitoring to understand the variations of VOCs concentrations in ambient air, as it adopts much simpler procedures in sampling, analysis, and data integration steps than manual monitoring methods. However, it should be noted that there is a high possibility of benzene artifacts formation through the Nafion dryer, which is often installed to remove water vapor in air samples before being adsorbed onto the cold trap. Therefore, if a Nafion dryer is used in any studies of monitoring VOCs, the benzene contamination should be carefully examined before carrying out obtaining the data.

• Analytical Science and Technology
• /
• v.8 no.4
• /
• pp.753-758
• /
• 1995

Thermal desorption/gas chromatography/mass selective detection method using Tenax cartridges for the determination of gaseous polycyclic aromatic hydrocarbons(PAH) is described. Glass fiber filter can collect only PAH in particulate. Gaseous PAH may penetrate the filter. Glass cartridge packed Tenax-GC was uses fur adsorption of gaseous PAH. The air of inhalation zone was collected fur 2-10 hours. Cartridges were thermally desorbed in the reverse direction to sample flow. The desorption conditions were as follows; desorption temperature; $300^{\circ}C$; desorption time; 20min; column head pressure; 30psi; inlet split vent; closed during desorption.

• Journal of Environmental Science International
• /
• v.22 no.12
• /
• pp.1539-1549
• /
• 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.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2010.10a
• /
• pp.148-151
• /
• 2010

화재증거물 속의 인화성물질을 분석하는 기술은 현재 다양한 추출 및 농축법을 활용한다. 본 연구에서는 Tenax TA를 이용하여 화재증거물 속의 인화성물질을 농축한 후 자동열탈착 장비를 사용하여 Tenax TA관 속에 농축되어 있는 인화성물질을 자동열탈착시켜 GC로 보낸 후 MS 분석하는 기술을 소개한다. 이러한 전처리과정을 사용하여, 화재증거물속의 인화성물질(경유, 등유 등)을 분석하였는데, 물로 화재증거물을 물을 이용하여 소화하여도, 시간이 오래지난 화재증거물이라도 열탈착 장비를 이용한 분석은 경유, 등유등을 확인하는데 유용하였다.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.17 no.1
• /
• pp.29-38
• /
• 1991

As the suitable place of the forest bathing, Two places of the needle-leaf trees, which are located in the Oh-Saek mineral spring near place from the Sorak mountain, were selected. And then, Headspace gas trapping apparatus were setted in that two places and the aromatic components of the forest were adsorbed by Tenax-TA column for 24 hours. And Tenax-TA column were analyzed by the GC SE GC-MS. The analyzed components were found to contain up to between 70-80% of pollutants, which are Toluene, Methyl Chloride, Hexane, p-Xylene, Benzene, ... etc. On the other hand, the aromatic components of the forest, which give aromatheraphitical effectness, are as follow: alpha-Pinene, Limonene, 1, 8-Cin-eol, Benzaldehyde, . . . etc.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.23 no.2
• /
• pp.261-267
• /
• 1994

Parched mugwort tea was manufactured from mugwort (Artemisia asicatica nakai) leaves by traditional green tea preparation method. Volatile flavor compounds were collected by Tenax GC and they separated on DB-5 capillary column ($60m\;\times\;0.25mm$ i.d.) Fifty eight compounds were isolated and identified by GC-MS from the volatiles. Eleven compounds incucluding benzaldehyde, pinene, myrcene, cineole, 2-phrrolidinonoe, camphor, thujong, 1-acetylpiperidine, caryophyllene, coumarin, and farnesol among the compounds identified were considered as important compounds contributing mugwort-like flavor to the parched mugwort tea. The mixture of these eleven authentic compounds could reproduce aroma of mugwort leaves harvested in April. As results, the concentrations of these eleven flavor compounds in parched mugwort tea may indicate the strength of mugwort-like aroma of the tea.

• Applied Biological Chemistry
• /
• v.37 no.2
• /
• pp.115-123
• /
• 1994

Allelopathic activity of the volatiles from leaves of Perilla frutescens an Artemisia asiatica was determined on the basis of bioassay, which tested germination and seedling growth of radish, rice, mung bean and lettuce. Seedling growth was more inhibited by phytotoxic volatiles than germination. Volatile components collected by headspace cold trapping-Tenax GC adsorption were analyzed by GC-MS. Fifteen volatile components in P. frutescens and 15 components in A. asiatica were identified. By steam distillation-extraction, 4 flavor components in P. frutescens and 10 components in A. asiatica were identified. The inhibitory activity of the fractions, obtained by steam distillation-extraction, was determined by virtue of bioassay on radish. Volatile allelochemicals of the most active fraction, neutral fraction, isolated from P. frutescens contained 9 components. In A. asiatica, 24 volatile allelochemicals were identified.