• Journal of Electrochemical Science and Technology
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• 제1권1호
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• pp.1-9
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• 2010

Conducting polymer films grown from various aromatic compounds have been evaluated as overcharge protecting additives for lithium ion rechargeable batteries. The polymer films were grown electrochemically under the conditions similar to those encountered during the overcharging processes of lithium batteries and subsequently characterized by potentiodynamic, electrochemical quartz crystal microbalance, electrochemical impedance spectroscopic, and scanning electron microscopic experiments. Results indicate that bicyclic and polycyclic aromatic hydrocarbons would be poor candidates for inhibitors, while biphenyl, terphenyl, and benzene derivatives displayed excellent performances. Mixed polymer films grown from o-terphenyl and p-xylene show the best performance among the candidates.

• 월간산업보건
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• 통권88호
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• pp.57-60
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• 1995

PAT program(The Proficiency Analytical Testing Program)은 미국산업위생협회(American Industrial Hygiene Association AIHA)와 미국산업안전보건연구원(National Institute for Occupational Safety and Health NIOSH)에서 공동주관하는 정도관리로서 일년에 4회 실시하고 있다. 실시항목은 금속(납, 카드뮴, 크롬, 아연), 유리규산, 석면, 유기,용제(Benzen, O-Xylene, Toluene, Carbon Tetrachloride, 1, 1, 1-Trichloroethane, Chloroform, Tetrachloroethylene, 1, 2-Dichloroethane, methanol, p-Dioxane)이다. 대한산업보건협회 산업보건연구소에서는 위의 4가지 항목을 모두 신청하여 1995년 1월에 실시된 120회 부터 참여하였는데 다음은 본 연구소의 120화에 대한 분석방법과 NIOSH로 부터 받은 결과이다.

• Bulletin of the Korean Chemical Society
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• 제25권6호
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• pp.779-785
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• 2004

Syn (or anti) cinnamaldehydeoxime (1a, b) undergoes Diels-Alder addition to tetrabromo-p-benzoquinone (2)in dry xylene in 1 : 1 and 2 : 1 molar ratios to give the mono- and diadducts 3 and 4a, b respectively. The reaction of 3 with thioamides in ethanol gave thiazoloquinoline diones 6a-d, whereas with acid amides in ethylene glycol, it gave oxazoloquinolinediones 12a-f.

• 한국연초학회지
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• 제23권1호
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• pp.40-44
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• 2001

This study was carried out to investigate relationship between contents of moisture and chemical components in burley tobacco after heat treatment. Initial moisture contents of burley tobacco was 32% after cutting and casing. Burely cut tobaccos were treated at various temperature(10$0^{\circ}C$, 13$0^{\circ}C$, 145$^{\circ}C$ and 16$0^{\circ}C$) and time(0, 5, 10, 15, 20 and 30 min) in mechanical convection oven. Moisture contents of burley tobacco after heat treatment were in the range of 1.9% to 18.4%. Relationship between moisture contents and total sugar, pH, total volatile base, ammonial, L value of color, nicotine, nornicotine, and $\beta$-nicotyrine contents were positively correlated. Correlation between moisture contents and crude ash, ether extracts, 2,6-deoxyfructosazine, 2,5-deoxyfructosazine, a value of color, citric acid, m-xylene, ${\gamma}$-butyrolactone and 5-methyl-2-furfural were negative.

• 상하수도학회지
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• 제13권3호
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• pp.91-100
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• 1999

Treatment conditions of DAF(Dissolved Air Flotation) and removal rates of VOCs(Volatile Organic Compounds) in mixed water of H raw water and VOCs were investigated. The used VOCs were benzene, toluene, ethylbenzene, and xylene in aromatic compounds and iso propyl mereaptan, n-butyl mereaptan, dimethyl disulfide, and iso butyl mercaptan in odors. The related parameters include water type, treatment method, clay concentration, pH condition, flocculation time, flotation time, per-cent recycle, water temperature, pressure. The removal rates of VOCs were different on treatment process and water condition. Treatment time was longer, removal rates of VOCs was higher. Water temperature was more important than pressure in DAF parameters. Molecular weight was related with removal rate in several kinds of VOCs were decraesed by competition of each component in II raw water. When algac blooming D water was treated by DAF, TCOD(Total chemical Oxygen Demand) and chorophyll a was removed over 96%.

• 한국대기환경학회지
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• 제23권1호
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• pp.39-49
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• 2007

In this study, the performance characteristics of solid phase microextraction (SPME) were investigated for three major odorous groups that consist of 10 individual compounds ([1] volatile organic compounds (VOC): benzene, toluene, p-xylene and styrene, [2] reduced sulfur compounds (RSC): hydrogen sulfide, methyl mercaptan, dimethylsulfide (DMS), dimethyldisulfide (DMDS), and carbon disulfide, and [3] amine: trimethylamine (TMA)). For the purpose of a comparative analysis, two types of SPME fiber ([1] polidimethylsiloxane/divinilbenzene (P/D) and [2] $Carboxen^{TM}$/polidimethylsiloxane (C/P)) were test ε d against each other for a series of standards prepared at different concentration levels (100, 200, and 500 ppb). To compare the analytical performance of each fiber, all standards were analyzed for the acquisition of calibration data sets for each compound. The results of P/D fiber generally showed that its calibration slope increased as a function of molecular weight across different VOCs; however, those of C/P fiber showed a fairly reversed trend. Besides, we confirmed that the application of SPME is limited to many sulfur compounds; only two compounds (DMS and DMDS) are sensitive enough to draw calibration results out of SPME. The calibration data for RSC show generally enhanced slop values for C/P relative to P/D fiber. However, in the case of TMA, we were not able to find a notable difference in their performance.

• Environmental Analysis Health and Toxicology
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• 제15권3호
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• pp.81-91
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• 2000

Residents who live near petrochemical industrial areas are exposed to a variety of petrochemicals, including benzene or benzene-containing liquids. It is a serious concern because some VOCs are carcinogens naturally present in petroleum and gasoline. The aim of this study was to assess the exposure to VOCs, measured by personal/indoor/outdoor air sampling, and to estimate the relationship between the air samples and biological monitoring data. Through biological monitoring, we investigated VOCs in blood and s-phenylmercapturic acid (s-PMA) , minor urinary metabolites of benzene. The external benzene exposure of subjects was measured using passive dosimeters and urinary s-PMA and blood-benzene were determined by GC/MS. More than 80% of subjects were detected for m-xylene, ethylbenzene, and toluene in blood samples and not detected at all for chloroform, 1 , 1 , 1 -trichloroethylene, and tetrachloroethylene. The mean concentration of benzene in the breathing zone of residents was 6.3 $\mu\textrm{g}$/m$^3$, personal, indoor and outdoor concentrations were strongly correlated to each other. s-PMA detected in all subject samples was affected by personal exposure (p< 0.05) and the level was different by age (p< 0.01). Blood benzene was not affected by external benzene during these periods .

• Journal of Korean Society for Atmospheric Environment
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• 제19권E3호
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• pp.129-136
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• 2003

Effects of inorganic aerosols on the kinetics of the hydroxyl radical reactions with selected aliphatic alkanes have been investigated using the relative rate technique. The relative rates in the absence and presence of aerosols were determined for n-butane, n-pentane, n-hexane, n-octane, and n-decane. P-xylene was used as a reference compound. Inorganic aerosols including (NH$_4$)$_2$SO$_4$, NH$_4$NO$_3$, and NaCl aerosols at two different aerosol concentrations that are typical of polluted urban conditions were tested. Total surface areas of aerosols were 1400 (Condition I) and 3400 $\mu$$m^2$ cm$^{-3}$ (Condition II). Significant changes in the relative rates in the presence of the inorganic aerosols were not observed for the n-butanel/$.$OH, n-pentanel/$.$OH, n-hexanel/$.$OH, n-octanel/$.$OH, and n-decanel/$.$OH reactions versus p-xylenel/$.$OH reaction. These results suggest that the promoting effects depend on the semiconducting property of the aerosols and the nature of the organic compounds.

• 한국연초학회지
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• 제24권2호
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• pp.113-120
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• 2002

This study was conducted to determine the smoke component changes by adding oriental, reconstituted, and expanded tobacco leaves. 7 different cigarette brands which were mixed with flue-cured, burley, oriental, reconstituted and expanded tobacco leaves were used for this study. 64 kinds of smoke components which were 6 of general components, 34 of semi-volatile and volatile components, 9 of acid components, and 15 of phenolic components were analyzed. All smoke components of mainstream smoke were changed by the different branding. As Tar, nicotine, ammonia, pH, all of acid compounds(except lacatic and glycolic acid) were decreased; HCN, levoglucosame, 4-vinyl phenol, 4-vinyl catechol, quinic acid-r-lactone, acetaldehyde, 2,3-butadiene, stylene were increased by adding oriental tobacco leaves. When the reconstituted tobaccos were added to 20%, the concentration of nicotine, all of acid compounds(except lactic. glycolic, palmitic acid) and all of phenol compounds were reduced; the concentration of ammonia, HNC, CO, aeconitrile, benzene, 2-butanone, moth-acrolene, butyronitrile, stylene, o-xylene were increased. As decreasing ammonia, pH, nicotine, all of acid compounds, all of phenol compounds, Isoprene, acetonitrile, 2-methyl-2-butene, 1,3-pentadiene, 2-nlethyl furane, ethylene cyclopentanone, ethyl bezene; increasing CO concentration were followed by adding expanded tobacco leaves.

• Environmental Analysis Health and Toxicology
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• 제9권1_2호
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• pp.37-51
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• 1994

To evaluate the genotoxicities of workers exposed to glue and glue cleaning solution, ambient air monitoring of working place, animal study and human monitoring were carried out. By GC-MS analysis, air samples collected from shoesmaking plant were found to be toluene, xylene, cyclohexane, n-hexane, methyl ethyl ketone, trichloroethylene, butylacetate, isopropyl alcohol. Glue and glue cleaning solution from shoesmaking plant were applicated topically to the CD-1 mice. DNA was isolated from skin 24 hr following the application and analysed for DNA-adducts using the nuclease $P_1$version of $^{32}$P-postlabelling assay. RAL (Relative Adduct Labelling, adducts$10^8$ nucleotides) was significantly increased in a dose-dependent manner in the glue cleaning solution treated mice skin. Peripheral blood DNA-adducts of workers exposed to glue and glue cleaning solution were also analysed by the same method, but there were not significant differences in the peripheral blood DNA-adducts level between exposed and control workers. In addition, glue cleaning solution from shoes factory was evaluated for mutagenicity in the Salmonella plate incorporation assay using strains TA 100 and TA 1535 in the presence and absence of Arochlor 1254-induced rat liver S$_{9}$. There was evident mutagenicity for cleaning solution in TA 100 regardless of $S_9$, but TA 1535 showed positive only in the absence of $S_9$when predicted by Stead model of mutagenicity prediction (p=0.0000). The urine concentrates from workers and controls were also assayed for mutagenicity towards strain TA 100 of Salmonella typhimurium in the presence of $S_9$ using Kado's microsuspension assay, but their mutagenic activities were not found to be significant. These data suggest that shoesmaking workers are exposed to genotoxic compounds and need to be monitored by testing the mutagenicity of human urines. However, $^{32}$P-postlabelling application requires further validation for the routine monitoring of human exposure.osure.