• 환경영향평가
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• 제20권4호
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• pp.497-507
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• 2011

This research studied human health risk assessment of benzene from industrial complexes of Chungcheong Province (Seosan industrial complex) and Jeonla Province (Iksan industrial complex and Yeosoo industrial complex). The residents near the industrial complexes areas can be often exposed to volatile organic compounds (e.g., benzene, toluene, xylenes) through a number of exposure pathways, including inhalation of the organic pollutant via various environmental matrices (air, water and soil), contaminated water, and soil intake. Benzene is well known to be a common carcinogenic and toxic compound that is produced from industrial and oil refinery complexes. In this study, a number of samples from water, air, and soil were taken from the residential settings and public school zones located near the industrial complex sites. Based on the carcinogenic risk assessment, the risk estimates were slightly above $10{\times}10^{-6}$ at all three industrial sites. According to deterministic risk assessment, inhalation was the most important route. The distribution of benzene in the environment would be dependent on vapor pressure, and the physical property influencing the extent of the potential risks. Non-carcinogenic risk assessment of benzene shows that the values of Hazard Index(HI) were much lower than 1.0 at all industrial complexes. Therefore, benzene was not a cause of concern in terms of non-carcinogenic risk posed to the residents near the sites. When compared to probabilistic risk assessment, the CTE(central tendency exposure) cancer risk values of deterministic risk assessment were close to the mean values predicted by the probabilistic risk assessment. The RME(reasonable maximum exposure) values fell within the range of 95% to 99.9% estimated by the probabilistic risk assessment. Since the values of carcinogenic risk assessment were higher than $10{\times}10^{-6}$, further detailed monitoring and refined risk assessment for benzene may be warranted to estimate more reliable and potential inhalation risks to receptors near the industrial complexes.

• 분석과학
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• 제20권3호
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• pp.237-245
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• 2007

현재 시중에서 판매되고 있는 비타민드링크 제품 중 20개사 31개 제품의 벤젠 함량을 headspace-solid phase microextraction(HS-SPME)법을 이용하여 GC/MS-SIM으로 분석을 하였다. SPME fiber는 $100{\mu}m$ PDMS를 사용하였다. 또한 정량방법은 표준물첨가법을 사용하였으며 40 mL vial에 용액 25 mL를 취하고 그 안에 자석젓개를 넣어 1200 rpm에서 교반시키고 4분 동안 흡착시킨 후 1분 동안 GC에서 탈착시켜 표준검량곡선을 작성하였다. 이 때 검량곡선의 상관계수 값은 0.999이상을 나타내었다. 검출한계는 시료를 분석할 때마다 산출하였는데 평균값이 0.56 ng/mL(${\pm}0.43$)이었으며 회귀식이 존재하는 농도의 범위는 0~40 ng/mL였다. 그 결과 시료 중 벤젠의 함유량은 nd~47.35 ng/mL의 농도의 범위였다. 전체 시료 중 15개의 제품에서 벤젠이 검출되었으며 그 중 5개의 제품에서는 벤젠의 함량이 먹는 물 수질기준인 10 ng/mL를 넘는 각각 16.99 ng/mL, 35.14 ng/mL, 16.03 ng/mL, 47.35 ng/mL, 14.28 ng/mL가 검출되었다.

• 청정기술
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• 제22권3호
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• pp.161-167
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• 2016

여러 가지 금속이온이 치환된 제올라이트에서 벤젠의 촉매연소 반응에 대해 연구하였다. 사용한 제올라이트 중 Y(4.8)형 제올라이트가 가장 높은 활성을 보여주었고, Y(4.8)형 제올라이트에 치환된 금속 이온 중 구리이온이 가장 높은 활성을 보여주었다. 촉매의 활성은 산소 TPD에 의해 얻어진 흡착산소의 양에 비례하였다. Cu/Y(4.8) 촉매에서 Cu 이온의 농도가 커질수록 반응활성이 증가하였다. 벤젠의 연소반응의 전환율은 반응물 중 벤젠의 농도보다는 산소 농도의 영향을 많이 받았다. 또한, 반응물에 첨가된 물은 촉매 활성을 감소시켰다.

• 한국안전학회지
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• 제21권3호
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• pp.45-52
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• 2006

The AITs(autoignition temperatures) describe the minimum temperature to which a substance must be heated, without the application of a flame or spark, which will cause that substance to ignite. The AITs are often used as a factor in determining the upper temperature limit for processing operations and conditions for handling, storage and transportation, and in determining potential fire hazard from accidental contact with hot surfaces. The measurement AITs are dependent upon many factors, namely initial temperature, pressure, volume, fuel/air stoichiometry, catalyst material, concentration of vapor, time lag. Therefore, the AITs reported by different ignition conditions are sometimes significantly different. This study measured the AITs of benzene, toluene and xylene isomers from time lag using AS1M E659-78 apparatus. The experimental ignition delay times were a good agreement with the calculated ignition delay times by the proposed equations wtih a few A.A.D.(average absolute deviation). Also The experimental AITs of benzene, toluene, o-xylene, m-xylene and p-xylene were $583^{\circ}C,\;547^{\circ}C,\;480^{\circ}C,\;587^{\circ}C,\;and\;557^{\circ}C$, respectively.

• 분석과학
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• 제5권1호
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• pp.25-31
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• 1992

벤젠합성장치를 제작하여 액체섬광계수법을 이용한 방사성탄소 연대측정 시료인 목재, 목탄, 패류, 토양 등의 시료의 처리에 이용하였다. 이산화탄소, 아세틸렌의 생성 및 최종적으로 얻어지는 벤젠으로 이어지는 합성과정별 실험조건을 최적화하였다. 본 벤젠합성기를 이용함으로써 유기시료의 경우, 15시간의 합성을 통하여 탄산칼슘 기준으로 85% 이상의 합성수율을 얻을 수 있었다. 합성된 벤젠의 순도는 GC/MS 측정결과 99.9% 이상이었다.

• 한국응용과학기술학회지
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• 제16권2호
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• pp.117-125
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• 1999

The alkylation benzene with 1-dodecene of Mordenite, Zeolite ${\beta}$ and Zeolite Y was studied in the stirring batch reactor. The kinds of zeolites were found to have influenced the reaction conversion and distribution of phenyldodecane isomer in the product. Compared to the alkylation conducted over Zeolite Y and Zeolite ${\beta}$, the alkylation over Mordenite exhibited higher distribution of 2-phenyldodecane and the alkylation conducted over Zeolite Y and Mordenite, the alkylation over Zeolite ${\beta}$ exhibited higher distribution of heavy alkylate which formed through oligomerization reaction readily deactivated the Lewis acid sites. A special feature of the effect of the benzene to 1-dodecene ratio the reaction conversion and selectivity of phenyldodecane isomer was found. At alkylation of benzene with 1-dodecene over Zeolite ${\beta}$, when the catalyst content in the system was high, the reaction will reach the optimal conversion at the higher B/D. When the benzene to 1-dodecene ratio was high, the selectivity of phenyldodecane isomer is high. It was also found that at the similar reaction conversion there was the same product distribution regardless of D/C ratio.

• 한국연초학회지
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• 제19권2호
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• pp.124-128
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• 1997

Semivolatile components in mainstream smoke of cigarette attached the different type filter were analysed. Based on the main peak of GC profile, benzene, toluene, acetic acid, limonene, acetamide, pyridine, nicotine, phenol, pyrrole, and furfuryl alcohol were identified. The amount delivered of semivolatile components by each filter was evaluated with the ratio of areas of sample vs area% of ISTD. By comparing dual and triple filter to mono filter, the delivery amounts were 52% benzene, 62% toluene and 74% benzene, 84% toluene, respectively. The delivery amount of limonene which was known of tobacco taste component, were 52%, and 93% by dual and triple filter, respectively. Also, delivery amounts of acetic acid which was one of acidic compounds in smoke, were 86% and 83% by dual and triple filter, respectively. When adding the same amount of active carbon, the amounts delivered of vapour phase such as benzene and toluene by dual filter were lower than that of triple filter. But the delivery amounts of acetic acid and phenol by dual filter were higher than that of triple filter. This results assume that the pH of active carbon in filter affect to the adsorption or absorption of triacetin during filter making process.

• Carbon letters
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• 제2권1호
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• pp.44-54
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• 2001

The characteristics of adsorption and desorption of benzene and toluene were investigated at a fixed bed packed with the activated carbon and activated carbon fiber. Through breakthrough experiments under various feed concentration conditions, it was found that the slope of mass transfer zone and the tailing in the breakthrough curves were different from the feed conditions due to different heats of adsorption. In hot nitrogen desorption, the regeneration time and mass transfer zone of the toluene desorption curve were longer than those of the benzene desorption curve because of the difference in adsorption affinity. With an increase in the regeneration temperature, the height of roll-up and the sharpness of desorption curves increased but the regeneration times decreased. The adsorption capacities of the activated carbon and activated carbon fiber after three-time thermal regenerations decreased about 25% and 37% for benzene and 18% and 25% for toluene, respectively. To investigate the effect of the regeneration temperature on the energetic efficiency, the characteristic desorption temperatures of toluene and benzene were investigated by calculating purge gas consumption and temperature.

• 한국환경성돌연변이발암원학회지
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• 제22권2호
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• pp.90-96
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• 2002

Benzene is a widespread human carcinogen, inducing leukemia and hematotoxicity. Exposure to benzene metabolites has been shown to cause genetic damage, including aneusomy and chromosome aberrations. Fluorescence in situ hybridization(FISH) procedure was used to determine if the benzene metabolite, 1, 2, 4-benzenetriol(BT), hydroquinone(HQ) and trans, trans-muconic acid(t,t-MA) induced specific chromosomal change in HL-60 cells. Treatment with BT, HQ and t,t-MA resulted in the induction of monosomy 8 and 21 in HL-60 cells in a dose-dependent manner. All of these metabolites also induced trisomy 8 and 21, but no correlation between frequencies of trisomy and concentration was found. Translocations between chromosome 8 and another unidentified chromosome ［t(8:\ulcorner)］, and between chromosome 21 and another unidentified chromosome ［t(8:21)］ were found. However, translocation between chromosome 8 and 21 ［t(8:21)］ was not found. Results indicate that the benzene metabolites, BT, HQ and t,t-MA, induce chromosome specific numerical and structural aberrations, and the fluorescence in situ hybridization (FISH) approach may be a useful and powerful technique for detection of aneuploidy.

• 한국산업보건학회지
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• 제8권1호
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• pp.105-114
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• 1998

In this study, 108 thinners were analyzed to identify their composition. The purposes of this study were to provide the data for MSDS and worker exposure levels. Thinners were collected from manufacturing industries, distributors and users. Wide ranges of thinner components were found ; Toluene, xylene, and ethyl benzene were most often found. Next, MIBK, cellosolve acetate, butyl cellosolve, and butyl acetate were found in 20-40 thinners. Others, such as acetone, n-hexane, cyclohexane, heptane, methylcyciohexane, octane and nonane were also found. There were about 5-6 components in each thinner. In the view point of Industrial Hygiene, Benzene was the most important component of thinners, which procures leukemia. Benzene was found from 8 kinds of thinners out of the total 108 surveyed. Thus, Content of benzene in thinners must be evaluated when industrial hygiene surveys are performed. Aromatic hydrocarbons were identified from 71 kinds of thinners out of total 108 and their contents were 10-87%. Alkanes were not contained in automobile painting, spraying, degreasing, urethane and epoxy thinners but lacquer, enamel and coating thinners.