• 한국산업보건학회지
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• 제5권1호
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• pp.104-118
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• 1995

This study was performed to evaluate factors affecting desorption of organic solvents collected on charcoal tube and to find out the optimum condition. Desorption efficiency for polar analytes was improved when several polar desorption solvents such as methanol, dimethylformamide(DMF), 2-(2-butoxyethoxy)ethanol were added to carbon disulfide($CS_2$). The best improvement was achieved when 10% dimethylformamide(DMF) in $CS_2$ was used as desorption solvent. During storage of polar analytes, recovery was greatly reduced. Especially, the recovery of cyclohexanone was decreased to 18.1 % after a month storage at $34^{\circ}C$. After two weeks storage, recovery of polar analytes was sharply decreased. Water adsorbed on charcoal interfered the recovery of polar analytes but didn't interfere that one of nonpolar solvent, toluene. When 10% DMF in $CS_2$ was used as desorption solvent, the effect of water on recovery was decreased, comparing with Desorption efficiency increased when analyte loading increased, and usage of 10% DMF in $CS_2$ decreased the loading effect. Increasing volume of desorption solvent was not effective to improve desorption efficiency of analytes when 10% DMF was used. Continuous shaking and sonication is not helpful to increase the desorption efficiency of analytes except cyclohexanone using 10% DMF. When silica gel used as adsorbent, methanol was better desorbent than dimethylsulfoxide. Analytes adsorbed on silica gel showed high recovery in low concentration and less affected by humidity. On the basis of this study, the following conclusions have been drawn. To improve the recovery of polar organic materials in air samples, it is necessary to analyze samples as soon as possible after they were collected. Otherwise, samples must be stored at low temperature. Using two components of desorption solvents, such as 10% DMF in $CS_2$, the effects of loading and humidity decreased for polar analytes such as methyl ethyl ketone and methyl isobutyl ketone. When work place has high humidity with low concentration of polar organic solvents, silica gel can be used as adsorbent, because it produces quantitative recovery for polar analytes at this condition. But it should be noted that high humidity makes breakthrough easy in silica gel samples.

• 한국식품과학회지
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• 제28권2호
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• pp.316-323
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• 1996

멥쌀, 찹쌀, 보리쌀, 밀가루로 담금한 발효 16일의 탁주 술덧의 향기성분을 비극성 column을 이용하여 GC와 GC-MS로 분석, 동정한 결과는 다음과 같다. 탁주의 향기성분은 alcohol 7종, ester 15종, acid 10종, aldehyde 1종, benzene 4종, phenol 3종, alkane 8종, ketone 2종 및 기타 5종 등 55종이 검출되었다. 시험구별로는 주모 무첨가 멥쌀주에서 35종, 주모 첨가의 멥쌀주 26종, 찹쌀주 15종, 보리쌀주 23종, 밀가루주 36종이 검출되어 휘발성 향미성분의 종류는 밀가루주에서 가장 많았고 멥쌀주의 경우 주모 첨가구보다 무첨가구가 많이 나타났다. 검출된 향기성분 중 acetix acid ethyl ester, 3-methyl-1-butanol, aceticacid, ethyl benzene, acetic acid 3-methyl butyl ester, 2-phentlethanol, 2,6-di-tert-butyl-4-methyl phenol, plumbagic acid, 1,2-benzenedicarboxylic acid dibutyl ester등 9종은 모든 시험구에서 공통으로 존재하였다. 이 외 2,4,6-trimethyl-1,3-benzenediamine은 주모 무첨가의 멥쌀주에서, diethyl sulfode, 4-methoxy ben-zaldehyde, docosane, 2-methyl propyl octadecanoic acid는 주모 첨가의 멥쌀주에서, propionic acid ethyl ester, acetic acid butyl ester, 2-hydroxy-4-methyl pentanoic acid, 2-methyl tridecane은 보리쌀주에서, 3-(methylthio)-1-propanol, hexanoic acid ethyl ester, butanoic acid mono methly ester, tridecanoic acid, ehtyl tetramethyl cyclopentadiene, 1,8-diaza-2,9-dik-etocyclotetradecane은 밀가루주에서만 각각 검출되어 담금 원료에 따라 향기성분이 특이하였다. 향기성분중 acetix acid ethyl ester, 3-methyl-1-butanol, acetix acid, 2-phenylethanol등의 성분이 다른 향기 성분에 비해 면적 비율이 높은 경향을 보였다.

• 환경위생공학
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• 제15권3호
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• pp.75-87
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• 2000

This study was conducted to investigate the composition, detection rate, and exposure concentration of the airborne organic solvents from the working environmental measurements of total 4181 different type of workplace in 3280 workshops in which organic solvents are used. The results are as follows : 1. For all workplaces except washing, the detection rate of toluene and benzene were 80% and 20%, respectively. 2. The number of detection of aromatic hydrocarbon and ketone were ranged 1.41-2.39 and 0.62-0.90 per a sample in all workplaces except that showed 1.01 in washing. 3. The mean of detection frequency was $3.3{\pm}2.5$ in all workplaces and there was no significant difference among that of each workplaces. 4. The airborne concentrations of methyl methacrylate, ethyl alcohol, methyl alcohol, and ethyl ether were $43.5{\pm}47.0{\;}ppm,{\;}22.5{\pm}51.0{\;},{\;}19.8{\pm}57.6{\;}ppm,{\;}19.8{\pm}40.14{\;}ppm, respectively. And those of cellosolve, methyl cellosolve acetate, and N,N-dimethyl formamide were $4.1{\pm}4.5$ ppm, $4.0{\pm}18.5{\;}ppm$, and $5.6{\pm}7.7{\;}ppm$, respectively and exceeded the occupational exposure limits enforced by Ministry of Labor in Korea. As the above results, it is suggested that the components of organic solvents should be indentified to efficient management, of working environment and conducted the engineering control for the workplaces using the hazardous materials.

• 한국세라믹학회지
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• 제23권5호
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• pp.41-46
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• 1986

공침법에 의하여 얻어진 고순도 극미립자인 $BaTiO_3$ 분말의 분산거동을 조사하였다 분산매로는 수용매와 비수용매인 methyl ethyl ketone(MEK)과 ethanol (ETOH)을 이용하였다 Suspension 에서의 입자의 분산상태는 pH 변화와 MEK, ETOH의 몰 비를 조절하여 각각의 suspensions에 polymer(polyvinyl butyral)를 첨가시켜 변화하였으며 그 거동은 유동학적 성질 침강 거동 electrokinetic 성질을 측정함으로써 파악되었다 비 수용매의 몰 비가 3:1 MEK/ETOH-$BaTiO_3$에서 polymer를 0.5~1% 첨가시켰을 때 입자의 분산이 가장 잘 이루어졌다.

• Applied Biological Chemistry
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• 제35권4호
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• pp.248-253
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• 1992

재래식 메주와 개량식 메주로 각각 담아 숙성시킨 된장의 향기성분을 연속 수증기증류 추출장치로 추출하여 상압에서 농축한 후, preparative GC로 GC-관능검사를 하고 GC/MC 분석과 Kovats retention index를 비교하여 동정하였다. 재래식 메주로 담은 된장의 향기성분으로는 alcohol류 11종, aldehyde류 4종, pyrazine류 2종, acid류 4종, furan류 3종, phenol류 3종, ester류 3종, hydrocarbon류 3종, ketone류 1종, 기타 성분 5종 등 39가지의 성분을 동정하였다. 개량식 메주로 담은 된장의 향기성분으로는 alcohol류 4종, aldehyde류 2종, pyrazine류 2종, acid류 2종, furan류 1종, ester류 2종, hydrocarbon류 1종, ketone류 2종, 함황 화합물 1종, 기타 성분 4종 등 21가지의 성분을 동정하였다. 한편, 재래식 메주로 담은 된장과 개량식 메주로 담은 된장에서 함께 동정된 향기성분으로는 3-methyl-1-butanol, 4-methyl-3-heptanol, trimethyl-pyrazine, 1-octen-3-ol, 2-furancarboxaldehyde, tetramethyl-pyrazine, benzaldehyde, 3-methyl-butanoic acid, naphthalene, 2-ethyl-3-methyl-oxetane 등 10가지 성분이었다.

• 한국산업보건학회지
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• 제11권2호
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• pp.135-144
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• 2001

This study was performed to measure airborne dimethylformamide(DMF), methyl ethyl ketone(MEK) and toluene and their urinary metabolites concentrations and to determine the relationship between airborne and urinary concentration. Airborne samples and their urinary metabolites were measured 98 male workers who work for 8 synthetic leather factories in a portion of Kyoung-In area. Urine samples were collected at end-of-shift to estimate the exposure levels. 1. The concentration of airborne DMF by process was 8.81 ppm for wet-mixing, 15.05 ppm for wet-coating, 6.03 ppm for dry-mixing, 5.58 ppm for dry-coating, 5.37 ppm for printing, and 9.03 ppm for total. There was statistically significant difference by process. Urinary NMF concentrations of wet-mixing, wet-coating, dry-mixing, dry-coating and printing were $90.55mg/{\ell}$, $79.80mg/{\ell}$, $39.86mg/{\ell}$, $25.23mg/{\ell}$, and $38.15mg/{\ell}$, respectively, and total geometric mean was $56.24mg/{\ell}$. There was significant difference by process. 2. The concentration of airborne MEK by process was 1.89 ppm for wet-mixing, 1.96 ppm for wet-coating, 10.33 ppm for dry-mixing, 29.24 ppm for dry-coating, 14.98 ppm for printing, and 4.87 ppm for total. There was statistically significant difference by process. Urinary MEK concentrations of wetmixing, wet-coating, dry-mixing, dry-coating and printing were $0.93mg/{\ell}$, $0.70mg/{\ell}$, $3.29mg/{\ell}$, $3.29mg/{\ell}$, and $1.06mg/{\ell}$, respectively, and total geometric mean was $1.25mg/{\ell}$. There was statistically significant difference by process. Urinary MEK 3. The concentration of airborne toluene by process was 0.35ppm for wet-mixing, 0.42ppm for wet-coating, 2.95ppm for dry-mixing, 11.67ppm for dry-coating, 4.88ppm for printing, 1.24ppm for total. There was statistically significant difference by process. Urinary hippuric acid concentrations of wet-mixing, wet-coating, dry-mixing, dry-coating and printing were 0.24g/g creatinine, 0.21g/g creatinine, 0.34g/g creatinine, 0.52g/g creatinine, and 0.29g/g creatinine, respctively and total geometric mean was 0.28g/g creatinine. There was statistically significant difference by process. 4. No. of exceeded KPEL was 40 workers(40.8%) for DMF(10ppm), 1 worker(1.0%) for MEK(200ppm), and no worker for toluene(100ppm). No. of exceeded KBEI was 62 workers(63.3%) for urinary NMF($40mg/{\ell}$), 29 workers(29.6%) for urinary MEK, 1 worker(1.0%) for urinary hippuric acid. 5. The regression equations were Log(NMF)=0.4094*Log(DMF)+1.3587(r=0.4516) for DMF, Log(MEKU)=0.1859*Log(MEK)-0.0324(r=0.3303) for MEK, Log(HA)=0.2106*Log(Toluene)-0.5685(r=0.4497) for toluene. Synthetic leather factory workers expose to 3 kinds of organic solvents which are DMF, MEK and toluene. Their urinary NMF and MEK levels were higher than their concentration levels through respiratory. It seems that the urinary levels were affected skin absorption for working habit and alcohol intake.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.212-212
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• 1994

본 연구소에서 분리하여 항암활성을 측정한바 있는 Sesquiterpene lactone계열의 KR-53170이 in vitro에 비해 in vivo에서 상대적으로 낮은 효력을 보이는데 착안 그 유도체들을 합성함으로써 in vivo stability 및 efficacy를 개선하고자 하였다. 합성된 물질의 in vivo activity는 human tumor cell중에서 A549(폐암), SK-OV-3(난소암1, SK-MEL-2(피부암), XF-498(중추신경계암), HCT-15(직장암)의 5개 암세포를 이용하여 ED$_{50}$($\mu\textrm{g}$/ml )를 측정하였으며 대조물질로는 KR-53170과 Cisplatin이 사용되었다. 그 결과 HR-53170의 terminal methyl ketone이 carboxylic acid로 변환된 CW-251001과 이것의 methyl ester인 CW-251002, ethyl ester인 CW-251003, 그리고 morpheline과 수용성으로 N-methylpiperazine, N-methyl-N'-aminopiperazine, 4-Piperidinopiperidine을 결합시켜서 합성한 CW-251011, CW-251012, CW-251013, CW-251014가 in vitro에서 어느 정도 활성을 유지하였다. 특히 이들중 CW-251001, CW-251012, CW-251013, CW-2s1014는 물에 대한 용해도가 상당히 개선되어 in vivo 활성검색을 위한 후보물질로 고려되었다. 하지만 이들중 CW-251001은 in vivo에서 낮은 농도에서는 활성이 거의 없었으며 놓은 농도에서는 독성을 나타내었다.

• Toxicological Research
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• 제30권3호
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• pp.199-204
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• 2014

The aim of this research was to improve our understanding of human toxicity due to exposure to DMF, MEK, or TOL individually as compared to exposure to DMF-MEK or DMF-TOL mixtures, by comparing $EC_{50}$ values as well as the morphological changes in HepG2 cells treated with these substances. We found that there was marked cell necrosis in the groups treated with mixtures than in those treated with the compounds alone, and that the amount of cell death and the $EC_{50}$ value were more dependent on MEK and TOL than on DMF. Moreover, analysis of the changes in effective concentration curves revealed that MEK had an antagonistic effect on the human toxicity of DMF, whereas TOL had a synergistic effect. Accordingly, these results suggest that in workplaces involved in the manufacture of synthetic leather, mixtures of DMF and TOL should be avoided as much as possible in order to minimize environmental toxicity and protect the health of the workers.

• 공업화학
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• 제21권4호
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• pp.430-434
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• 2010

금속분말에 바인더, methyl ethyl ketone (MEK), cyclohexanone을 혼합한 슬러리를 이용하여 전자파 차폐용 시트를 제조하였으며, 이때 전기전도성이 높은 carbon nanotube (CNT)를 첨가하여 차폐효율을 증가시키고자 하였다. 제조된 시트는 주사전자현미경(SEM)과 energy dispersive spectroscopy (EDS)를 이용하여 표면분석과 성분분석을 실시하였다. 시트의 전기적 특성과 차폐효율은 4-Point Probe와 전자파차폐효율측정기를 이용하여 측정하였다. 전기저항은 CNT를 2% 첨가한 시트가 $13.13{\Omega}{\cdot}cm$로 가장 낮은 값을 나타내었으며, 전자파 차폐 효율 역시 CNT를 2%첨가한 시트가 63 dB로 가장 높은 값을 가지는 것으로 평가되었다.

• 한국산업보건학회지
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• 제24권2호
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• pp.238-245
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• 2014

Objectives: It was known that workers in synthetic leather company are mainly co-exposed to dimethylformamide(DMF) with methyl ethyl ketone(MEK) or toluene(TOL) instead of a single dimethylformamide. This study was examined to the physico-chemical properties in single DMF and binary mixture DMF with MEK or TOL. Materials: Physico-chemical properties were measured by Korean and American Standard Test Methods. Results: Boiling point, specific gravity and flash point in single DMF were significantly higher than binary mixture DMF with MEK or TOL and such difference was dependent on the mixing ratio of MEK and TOL, and low explosion limit in binary mixture DMF with TOL was only significantly lower than single DMF. However, Reid vapor pressure had significantly higher in binary mixture DMF with MEK or TOL compared with single DMF. Conclusions: Our results demonstrate that the binary mixture DMF with MEK or TOL synergistically increases volatilization of DMF. It was concluded that the interaction between DMF and MEK and/or TOL might play a key role in the volatilization process of DMF under environmental conditions of workplace.