• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.1
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• pp.173-184
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• 1990

This study is an experimental research on the treatment of phenolic wastes by Rotating Biological Contactors(RBC). The objective of this study is to determine the optimum range of influent phenol concentration and organic loading rate. Organic removal rates were analyzed with increasing organic loading and influent phenol concentration, together with the observation of microorganism. Biomass, SCOD, and phenol concentration were measured under the steady state after a step change of influent phenol concentration. As the result, at the phenol concentration less then 98.8 mg/L there were no evidence of substrate inhibition. As the results, organic removal rates in each stage at various organic loading, were decreased with increasing phenol concentration. First order kinetic was observed on the removal of SCOD for which phenol concentration is within the range of substrate inhibition. And also, microorganisms were changed with influent phenol concentration. Namely, at low influent phenol concentration, thin biofilm with filamentous growth was produced. To the contrary, thick biofilm with nonfilamentous growth was produced at high influent phenol concentration.

• Korean Journal of Microbiology
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• v.35 no.3
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• pp.237-241
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• 1999

Phenolic resin wastewater contained 41,000 mglI phenol, 2,800 mg/l fonualdehyde and various chlorinated phenolic compounds. Candida tropicalis PW-51 isolated [rom the natural enVlfooment was able to degrade 1,000 mg/l phenol in the presence of 100 mglI formaldehyde, but it took much time to degrade phenol with the increase of formaldehyde in phenolic resin wastewater. %en the phenolic resin wastewater was diluted to 1/40, the initial concentration of phenolic compounds (phenols) was 882 mglI and degraded to 81 mglI by C tfVpicalis PW-51 in batch culture. In a continuous biological treatment, the phenolic resin wastewater was diluted to 40 (745 mglI), 20 (1,356 mglI), or 10 (2,875 mglI) times. The removal efficiency of phenols in 1/40- and lI20-diluted phenolic resin wastewater was about 92%, but the phenols in 1!1O-diluted wastewater were not degraded. The remained phenols in wastewater were absorbed by a mixture of activated carbon and rice bran (1:1, v:v) in the process of absorption which was connected to the biological treatment. The total removal efficiency of phenols in 1!40~ and l/20-diluted phenolic resin wastewater was 99.9%.

• Korean journal of food and cookery science
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• v.15 no.1
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• pp.55-60
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• 1999

Free phenolic acid, soluble phenolic acid ester and insoluble bound phenolic acid were extracted from defatted perilla flour. Their antioxidative effects were compared with those of BHA, AE and TBHQ for soybean oils by measuring acid and peroxide values at 60$^{\circ}C$ for 25 days. The patterns of these extracts were compared by using gas chromatography. Free phenolic acid and soluble phenolic acid ester extracts showed a higher antioxidative effects than BHA and AP. Among phenolic extracts, free phenolic acid showed the most effective antioxidant activity in soybean oil. Six types of free phenolic acid, 3 types of soluble phenolic acid ester, and 2 types of insoluble phenolic acid were found in the extract.

• 월간산업보건
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• s.262
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• pp.26-29
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• 2010

펜타클로로페놀의 현재 직업적 노출기준은 $0.5\;mg/m^3$(TLV-TWA)으로 권고하고 있다. 이 수치는 눈, 점막과 상기도의 염증과 발한, 열, 위장 불만, 시각 장해, 중추 신경계와 심혈관계 장해를 유발할 수 있는 급성 독성의 가능성을 최소로 하는 것을 목적으로 설정하였다. Chloracne는 공업용 펜타클로로페놀을 사용하거나 펜타클로로페놀을 생산하는 근로자들에 대해서 보고하였다. 펜타클로로페놀은 피부를 통해서 즉시 흡수되는데, 이 물질의 조직 독성은 펜타클로로페놀을 포함한 용액이나 펜타클로로페놀로 오염된 의류와 접촉된 사람에게서 보고되었다. 따라서 피부경고주석은 적합한 것으로 판단되었다. 펜타클로로페놀의 발암성 잠재력에 대한 명확한 증거는 간세포성과 신장에 가까운 신생물이 관찰된 설치류 생물 검정에서 발견되었다. 그러므로 본 물질은 인간에게 불명확한 관련성을 가진 동물성 발암물질(A3)로 설정하였다. 충분한 자료가 확보되지 않아 감작성 (SEN) 경고주석 또는 TLV-STEL은 권고되지 않았다. 펜타클로로페놀은 생물학적 노출지수(BEIs)가 권고된 물질이다.

• Journal of the Korean Society of Food Culture
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• v.14 no.1
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• pp.43-48
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• 1999

The antioxidative effects of phenolic acids extracts from defatted sesame meal were investigated on the soybean oil. The free, ester and insoluble bound phenolic acids in the extracts from defatted sesame meal were isolated and their antioxidative activities were evaluated with commercial synthetic antioxidants such as BHA, AP and TBHQ. The patterns of these extracts were compared by using gas chromatography. Ether extracts from the defatted sesame meal showed a higher antioxidative effectiveness than BHA and AP. Among phenolic extracts, free phenolic acid and soluble phenolic acid ester were found most effective in the sesame meal. Each phenolic extract was confirmed to be composed of six or three individual compounds.

• Analytical Science and Technology
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• v.17 no.5
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• pp.393-400
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• 2004

Nitrosation of phenol (POH) was studied by adding hydrochloric acid and sodium nitrite to phenol solution with reaction temperature and time change. The optimum condition of nitrosation was found from the effects of hydrochloric acid and sodium nitrite concentration, reaction temperature, and reaction time changes on the production of nitrosophenol (POHNO). As a result, it was found that the optimum conditions were $5.0{\times}10^{-4}{\sim}2.0{\times}10^{-3}M$ range of $NO{_2}^-$ concentration, more than 0.10 M of HCl concentration, temperature of $80^{\circ}C$, and 3 hrs. of reaction time. In this condition, 10 U.S. E.P.A. classified priority environmental pollutant, phenols, were nitrosated. Nitrosated phenols were: POH, 2-Chlorophenol (2ClPOH), 2,4-diChlorophenol (2ClPOH), 2,4-dimethylphenol (24diMPOH), and 4-Chloro -3-methylphenol (4Cl3MPOH), and a small part of 2-nitrophenol (2NPOH). The ${\lambda}_{max}$ values of nitrosated phenols in acidic solution were around 300 nm, and those in basic solution were around 400 nm. Molar absorptivities (${\varepsilon}$) at the 400 nm of the nitrosated phenols in the basic solution were 1.5~2.0 times larger than those at 300 nm in acidic solution. It was also found by Capillary-HPLC chromatograms of the nitrosated phenol solutions that the production of the nitrosophenols were interfered by the excess concentration of nitrite (more than $3.0{\times}10^{-3}M$).

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.9-14
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• 1993

The free, ester and insoluble bound phenolic acids in the extracts from defatted perilla seed flour were isolated and their antioxidative activities were evaluated in comparison with commercial synthetic antioxidants. Total phenolic content of the perilla seed was 0.75% as chlorogenic acid. Each percent ratio of the content of free, ester, and insoluble bound phenolic acid to total phenolic content was 87.5, 7.5 and 5.0% respectively. Chlorogenic acid was identified as a major phenolic acid and a small amount of caffeic acid was also identified in the free phenolic acid extract, but they were not found in soluble ester and insoluble bound phenolic extracts by two dimensional paper chromatography. Each type phenolic extract from 30g of deffated perilla flour showed antioxidant activity similar to that of BHT (0.02%, w/w) in 200g of soybean oil substrate inspite of the difference of each phenolic content.

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.572-578
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• 2006

The accumulation of phenol in apples was measured by exposing them to phenol vapor at $25^{\circ}C$. The effective diffusivities of phenol in the rind and flesh of apples were estimated by comparing the experimentally determined fractional uptake curve with the simulated ones based on a consecutive diffusion model in the rind and flesh. Phenol was detected in the flesh of apples after 5 day exposure due to its slow diffusion in the rind. The consecutive diffusion model of phenol in apples simulated well the measured fractional uptake curve when the effective diffusivities of phenol in the rind and flesh were assumed to be $5.0{\times}10^{-13}m^2/s$ and $1.5{\times}10^{-10}m^2/s$, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.949-957
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• 2000

This study investigates the remediation of the phenol or PNP(p-Nitrophenol) contaminated soils in a slurry reactor by a pure culture, P-99. The application of a pure culture for the phenol decontamination make the degradation rate three times faster than that of the mixed activated sludge. The destruction of 300 mg/L phenol was completed in 26 hours. As 1 mg of phenol was added, 0.1457 mg of microorganism was grown in the medium. The pure culture could not utilizes PNP, one of the xenobiotics, as a growth substrate. When the bacteria was induced by phenol enrichment medium. PNP could be effectively transformed with cometabolic process. The induction of the bacteria requires 1 mg of phenol for the destruction of 0.027 mg PNP. When PNP concentration in the medium contained phenol and PNP increased. the degradation rate of phenol was decreased. The degradation rate of phenol and PNP in the slurry reactor was about two times faster than in the reactor without slurry because of higher dissolved oxygen supply in the aqueous phase and adsorption on the surface of the soil.

• Journal of Korea Soil Environment Society
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• v.5 no.2
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• pp.3-12
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• 2000

This study was carried out to evaluate the effect of aeration on removal of phenolic compounds in soils. Phenol, 2,4-dichlorophenol, and pentachlorophenol as phenolic compounds were chosen in this study. Texture of soil used was sandy loam. Temperature and moisture content of the soils in lab-scale reactors were maintained at $25^{\circ}C$ and at 15%, respectively. Phenolic compounds vaporized from reactors were trapped by methylene chloride solution. Phenolic compounds were applied to the soils as individual compound Aeration improved the phenol degradation rate in soil, while it did not in case of 2,4-dichlorophenol and pentachlorophenol. The amount of phenol vaporized by aeration was only 0.3of of that of initial phenol compound added to the soil. First order kinetics described the degradation rates of phenolic compounds better than zero order kinetics.