• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.2
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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.

• Journal of the Korean Chemical Society
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• v.40 no.9
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• pp.615-622
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• 1996

(Benzotriazol-1-yl)arenesulfonylalkanes, 2a, 2b, 3a and 3b, were prepared by lithiation of 1-(benzotriazol-1-yl)arenesulfonylmethanes followed by reaction with alkyl iodides. Very bulky molecules such as 1,1-di(benzotriazol-1-yl)-1-aryl-1-thiophenoxymethanes 5, 1,1-di(benzotriazol-1-yl)-1-thiophenoxymethane 9a and 1,1-di(benzotriazol-1-yl)-1,1-dithiophenoxymethane 9b were synthesized. 1,1-Di(benzotriazol-1-yl)-1-benzenesulfoxymethane 10a and 1,1-di(benzotriazol-1-yl)-1-benzenesulfonylmethane 10b were also synthesized by the oxidation of compound 9a, while oxidation of sulfide group on compound 5 and 9b by m-CPBA were not successful. On the other hand, pyrolysis and hydrolysis of 3-(benzotriazol-1-yl)-3-toluenesulfonylpentane 3b gave 3-toluenesulfonyl-2-pentene 11 and diethyl ketone 13a, respectively, which means there are both C-N and C-S bond cleavages.

• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.256-259
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• 1992

The 14-membered tetraaza macrocyclic ligand 1,8-diethyl-5,12-dimethyl-1,4,8,11-tetraazacyclote tradeca-4,11-diene(B) can be synthesized as its dihydroperchlorate salt by the one-pot reaction of 2-ethylaminoethylamine, methylvinyl ketone, and perchloric acid in absolute ethanol. The reaction of Ni(II) or Cu(II) ion and the salt yields $[M(B)]^{2+}$ (M = Ni(II) or Cu(II)), which reacts with $NaBH_4$ to produce $[M(D)]^{2+}$ (D = 1,8-diethyl-5,12-dimethyl-1,4,8,11-tetraazacyclote tradecane). The complexes $[M(L)]^{2+}$ (L = B or D) have planar geometry and contain two ethyl groups at the donor nitrogen atoms of the ligands. The red solids $[Cu(B)](X)_2(X)$ = $ClO_4-$ or $PF_6^-$) react with water molecules of atmospheric moisture to produce the purple solids in which water molecules are coordinated to the metal ion. Synthesis, characterization, and the properties of the new N-ethylated macrocyclic ligands and their Ni(II) and Cu(II) complexes are reported.

• The Korean Journal of Food And Nutrition
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• v.13 no.5
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• pp.483-489
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• 2000

Wild Chopi leaves were harvested near Chounghwa Mt. Sangju city in Kyungpook province. Chopi leaves were dried naturally and crushed with and without blanching. From mechanical analysis(GC). fifty five peaks were identified as volatile materials in no blanching leaf. Among the fifty five peaks, twenty three peaks were identified as hydrocarbones(dodecane, sabinene, myrcene etc.), ten peaks as alcohols (isobutylalcohol. cis-pentenol, 1-pentenol, 1-penten-3-ol etc.), seven peaks as aldehydes (3-methylbua-tanal, hexanal, 2,6-dimethyl hept-5-al etc.), four peaks as ketones(3-hydroxy-2-butanone, 2-nonanone, 2-undecanone, 2-tridecanone) and six peaks as esters ( cis-3-hexenyl acetate, linalyl acetate. citronellyl acetate, nervy acetate etc.). Other peaks were founded as 3-cyano-2,5-dimethylpyrazine, dimethyl sulfide, chloroform, 1,8 cineole. Thirty five peaks were identified as volatile materials in blanching leaf. Twenty peaks were identified as hydrocarbones(1,1-oxybis-ethane, $\alpha$-pinene, camphene. myrcene, $\beta$-phellan-drene, $\beta$-caryophyllene etc.), as alcohol(L-linalool, (-)-isopulgerol, $\alpha$-terpineol. citronellol etc.), as aldehydes(nonanal, citronellal), as ketones(2-undecanone, 2-tridecanone etc.) and as esteres(citronellyl acetate. cis-3-hexenyl acetate, neryl acetate etc.). Other peaks were found as 3-cyano-2,5-dimethyl-pyrazine. The amount of volatile materials such as $\alpha$-pinene, myrcene, $\beta$-phellanderene, L-linalool, citronellal, citronellyl acetate, $\beta$-caryophyllene were detected abundantly among the volatile materials.

• Applied Biological Chemistry
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• v.46 no.3
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• pp.207-213
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• 2003

Kochujang was prepared for this study with raw material inoculated by commercial enzyme of amylase and protease. Volati1e compounds of Kochujang were analyzed using a purge and trap method during fermentation and identified with GC-MSD. Total 54 kinds of volatile flavor components like 16 kinds of alcohol, 16 kinds of ester, 7 kinds of acid, 4 kinds of aldehyde, 2 kinds of alkane, 1 kind of benzene, 3 kinds of ketone, 1 kind of alkene, 2 kind of amine, 1 kind of phenol, other 1 were found. Total number of volatile flavor detected right after manufacturing were 23 kinds like 3 kinds of alcohol, 6 kinds of ester, 3 kinds of aldehyde. After 30 days storage, total number of volatile flavor went up to 31 kinds with addition of 4 kinds of alcohol, 1 kind of ester. The total number of volatile flavor after 120 days storage were increased to 49 kinds. Volatile flavor compounds detected during the storage period were total 20 kinds like 6 kinds of alcohol such as 2-methyl-1-propanol, ethanol, 3-methyl-1-butanol, 5 kinds of ester such as ethyl acetate, isoamyl acetate, ethyl butyrate, 3 kinds of aldehyde such as butanal, acetaldehyde and 6 kinds of others. Even though peak area % of flavor compound varied depends on fermentation period, ethanol, ethyl acetate, ethyl butyrate, ethenone, 2-methyl-1-propanol, 3-methyl-1-butanol were the main compounds that consisted of flavor from Kochujang which was made with enzyme treatment. Ethly acetate showed the highest result in the treatment of right after manufacturing, 3-methyl-1-butanol had up to 90th day and ether were the other days.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.2
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• pp.73-78
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• 2012

In this study, three different synthetic musk compounds (SMCs) in the Nakdong river water (raw water) and rapid sand filtered water were treated by $O_3$ process. The experimental results showed that the removal efficiency of musk ketone (MK) was lower than removal efficiency of AHTN (7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene) and HHCB (1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[c]-2-benzopyran) for both the raw water and the rapid sand filtered water. And in general, the removal efficiencies of three SMCs in the raw water were lower than that in the sand filtered water. Under the $O_3$ dose of 0.5~10.0 mg/L, the removal rate constants (k) of three SMCs for the raw and sand filtered waters increased rapidly with the increased $O_3$ dose. In the case of drinking water treatment plants (DWTPs) which were selected pre- and post-$O_3$ processes (located in the downstream of Nakdong River), operation conditions of pre- and post-$O_3$ process were $0.5{\sim}2.0mg{\cdot}O_3/L$ (2~4 min) and $0.5{\sim}2.5mg{\cdot}O_3/L$ (6~8 min). Therefore, $O_3$ doses and contact times of same conditions with above were very difficult to remove SMCs in DWTPs.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2348-2354
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• 2018

We designed a conceptual model of the 2.3-BDO dehydration process using a hydroxyapatite-alumina catalyst and estimated its economic feasibility to predict the appropriate range of the purchase price of 2,3-BDO on commercial scale. The conceptual design and economic analysis can offer valuable information for the industrial application of 2,3-BDO because the most relevant studies have limitation in laboratory scale. Furthermore, the adequate range of 2,3-BDO price, in which the process has profitability, was investigated with the current market prices of 1,3-BD. The investigated price in terms of 2,3-BDO dehydration can pertain to estimation of the economic feasibility in 2,3-BDO production process.

• Bulletin of the Korean Chemical Society
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• v.12 no.1
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• pp.26-31
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• 1991

Facile and efficient syntheses of terpenic perfumeries cis-jasmone, dihydrojasmone, and tetrahydrojasmone have been investigated. Cis-jasmone was synthesized by successive metallation followed by alkylation of acetone N,N-dimethylhydrazone with (Z)-2-penten-1-yl tosylate (or 2-pentyn-1-yl tosylate) and propylene oxide in one flask to give a ketonic alcohol, which was oxidized to the corresponding diketone, followed by base-catalyzed intramolecular aldol condensation to give a regioselective cyclization product. Dihydrojasmone and tetrahydrojasmone could be conveniently obtained from 2-octanone. The dimethylhydrazone of the ketone was lithiated with butyllithium and reacted with propylene oxide to give a ketonic alcohol, which was oxidized to a diketone, followed by base-catalyzed intramolecular cyclization to afford dihydrojasmone. Tetrahydrojasmone was prepared by converting the ketonic alcohol into corresponding iodoketone, followed by base-catalyzed intramolecular cycloalkylation to furnish an odoriferous product.

• Bulletin of the Korean Chemical Society
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• v.17 no.1
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• pp.50-55
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• 1996

Reaction of carbonyl compounds with diisopinocampheylhaloboranes (Ipc2BX,X=Cl, Br, I) was investigated in detail in order to establish their usefulness as selective reducing agents. The reagents reduced aldehydes and ketones to the corresponding alcohols. The reactivities are in the order of Ipc2BCl Ipc2BBr>Ipc2BI.The reagents also reduced ${\alpha}{\beta}-unsaturated$, aldehydes and ketones to the corresponding allylic alcohols without any detectable 1,4-reduction. Especially, the chloro derivative nicely achieved the selective reduction of aldehyde or ketone groups in the presence of many other functional groups. The most remarkable result of this investigation is that aldehydes and ketones can be selectively reduced in the presence of acid chlorides.

• Bulletin of the Korean Chemical Society
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• v.18 no.7
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• pp.754-760
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• 1997

Through a sequence of reactions including Diels-Alder cycloaddition of a furan diene as the key step, 11-oxatricyclo[6.2.1.01,6]undecyl rings were synthesized from 5-methylfurfural with the goal of developing a synthetic protocol to 11-oxabicyclo[6.2.1]undecyl system. The strategy to incorporate an oxygen atom at C6 carbon of tricyclic 11 or 16 by Baeyer-Villiger oxidation was unsuccessful, implicating that there is too much steric congestion around the carbonyl ketone. As an alternative approach, bicyclic 23 and 24 were prepared from 2-methylfuran via known tricyclic 20. Cyclization of bicyclic 23 and 24 under several reaction conditions also failed to produce hydroxylated product 25 and 26.