• Title/Summary/Keyword: solvents

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An Analysis of the Factors Affecting Anemia in the Female Industrial Workers -Case-Control Study- (산업장 여성 근로자의 빈혈에 영향을 미치는 요인 분석 -환자-대조군 연구-)

  • Park, Myeong-Ho;Kim, Yong-Joon
    • Journal of Preventive Medicine and Public Health
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    • v.22 no.2 s.26
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    • pp.181-188
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    • 1989
  • In this study an attempt was made to determine the factors affecting anemia in female industrial workers. The population was identified through the records of screening examinations given by Kosin Medical Center to the industrial workers in Sasang Industrial Complex during the period from March 1987 to October 1988. One hundred twenty eight cases were selected from the records screening examination of 155 anemic patients. A case-control study was carried out using matched 128 anemic cases and 128 non-anemic workers who were selected by simple random sampling. Age was matched, and their occupational history, general characteristics, physical characteristics and health status were analyzed. The results were; 1. In the anemic group, educational level was lower, and the frequencies of irregular menstruation and poor appetite were higher than in the control group but these differences were statistically not significant. 2. The percentage of workers working with organic solvents, working hours and years of service (total years exposed to organic solvents) were significantly higher in the anemic group than those in the control group. 3. A career exposed to organic solvents was more influential factor affecting anemia in the female industrial workers rather than menstruation amount of other factors, and it was statistically significant.

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Adsorption Equilibrium of Rhodamine 6G onto the Conchiolin Layer from Aqueous Solution (수용액중의 Rhodamine 6G 염료의 콘키오린 층에 대한 흡착평형)

  • Shin Choon-Hwan;Song Dong-lk
    • Journal of Environmental Science International
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    • v.14 no.12
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    • pp.1195-1201
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    • 2005
  • In order to develop a dye coloring technology on Conchiolin layer in cultured pearls, appropriate dyes were selected, their solubilities in various solvents were studied, and adsorption and desorption experiments were performed. Solubilities of several basic dyes known to suitable for the pearl coloring, i.e., Rhodamine 6G(R6), Rhodamine B(RB) and Methylene Blue(MB), in several solvents (distilled water, methanol, ethanol, and acetone) were investigated. Among these dyes, R6 was chosen as a dye for single component adsorption and desorption experiment due to the relatively good solubility in various solvents tested. Solubilities of dyes were judged to be enough to color the pearls since dye concentrations in pearl coloring are, in general, not so high. The internal surface area of the pearl layer is believed to be directly related to the dye adsorption, the single-point internal surface area of the pearl layer measured at the nitrogen relative pressure of 0.3 was found to be $0.913m^2/g$, and the BET internal surface area, $1.01m^2/g$ The most probable diameters of micropores and macropores were found to be $40{\AA}$and $5000{\AA}$ respectively, from the pore size distribution data. Adsorption isotherm was well fitted to the Langmuir isotherm model, resulting in q=$\frac{1.62C}{1+1.09C^{.}}$

Effect of chemical and physical structure on partitioning behavior of representative printing ink solvents and various food ingredients (식품 성분과 식품 포장용 인쇄 잉크 용매의 화학적 구조가 분배작용에 미치는 영향)

  • An, Duek-Jun
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.10 no.1
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    • pp.7-14
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    • 2004
  • Migration behavior of selected solvents and food samples showed differences of the chemical structures and polarities, the food samples which have similar polar expresses more higher affinity than different polar degrees. Water which is polar has a highest partitioning coefficient values on polar isopropanol, and oil which is nonpolar has highest partitioning value on non-polar toluene. The increasing order of partitioning values was accord with increasing water contents in food samples. It is showed that the wheat flour with 13.2% moisture content has the highest partitioning coefficient values on the isopropanol with -OH. Kp value of sugar showed remarkable lower partitioning coefficient values than other food samples due to high degree crystallinity. This phenomenon can be predictable with ${\delta}$ values, because order of partitioning coefficient values which comes out through the experiment and the sequence of Hildebrand solubility parameter value difference between food sample and printing ink solvent correspond almost. This Hildebrand solubility parameter value can be easily applied to the food package industry because the effect of food-safety can be considered without passing through complicated steps by using this method.

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Removal of Oily and Particulate Soils from Silk Fabrics (견직물에 부착한 지용성 오구 및 고형 오구의 제거)

  • Lee, Jeong-Sook
    • Fashion & Textile Research Journal
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    • v.7 no.6
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    • pp.680-688
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    • 2005
  • This study was carried out to investigate on the removal of oily and particulate soils from silk fabrics. Various kinds of solvents were used on the removal of two kinds of soils treated into the silk fabrics. The removal of oily soil was analyzed by liquid scintillation counting method, and the removal of oil and carbon particulate mixed soils was evaluated by measuring of reflectance on the surface of soiled fabrics with/without drysoap in solvent washing by Terg-o-tometer. The surfaces of fabrics were also observed by SEM before and after washing. The results obtained were as follows : oily soils were removed efficiently by various kinds of solvents regardless of kinds of silk fabrics in short washing time. The removal effect of solvents from the soiled silk fabrics were high in the order of isopropyl alcohol>trichloroethane>monochlorobenzene>ethylether>perchloroethylene. Oil and carbon particulate mixed soils could be efficiently removed by adding of drysoap in solvent washing. The removal of mixed soils were increased drastically with rinsing and increased drysoap. The removal of soils was more efficiently removed from degummed silk fabrics than from the raw silk fabrics.

Development of Analytical Technology Using the HS-SPME-GC/FID for Monitoring Aromatic Solvents in Urine

  • Lee, Mi-Young;Chung, Yun Kyung;Shin, Kyong-Sok
    • Mass Spectrometry Letters
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    • v.4 no.1
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    • pp.18-20
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    • 2013
  • Headspace solid phase micro-extraction gas chromatography/flame ionization detection (HS-SPME-GC/FID) method was compared with headspace gas chromatography/mass selective detection (HS-GC/MS). Organic solvent-spiked urine as well as urine samples from workspace was analyzed under optimal condition of each method. Detection limit of each compound by HS-SPME-GC/FID was $3.4-9.5{\mu}g/L$, which enabled trace analysis of organic solvents in urine. Linear range of each organic solvent was $10-400{\mu}g/L$, with fair correlation coefficient between 0.992 and 0.999. The detection sensitivity was 4 times better than HS-GC/MS in selected ion monitoring (SIM) mode. Accuracy and precision was confirmed using commercial reference material, with accuracy around 90% and precision less than 4.6% of coefficient of variance. Among 48 urine samples from workplace, toluene was detected from 45 samples in the range of $20-324{\mu}g/L$, but no other solvents were found. As a method for trace analysis, SPME HS GC/FID showed high sensitivity for biological monitoring of organic solvent in urine.

Residual Solvents and Mineral Contents in Ginseng Extracts with Different Extracting Conditions (추출조건에 따른 인삼농축액 중의 잔류용매 및 무기물 함량)

  • Lee, Seon-Hwa;Kim, Woo-Seong;Kim, Yong-Mu;Hong, Yeong-Pyo;Ahn, Yeong-Soon;Park, Heung-Jai;Kim, Ok-Hee
    • Journal of Environmental Science International
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    • v.16 no.1
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    • pp.39-44
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    • 2007
  • This study was conducted to investigate the contents of residual solvents and mineral components(11 kinds) in ginseng extracts with different extracting conditions(5 types) and commercial ginseng extract products(domestic, imported). Fine root was extracted with solution having various ethanol concentration after hexane treatment. Among 5 type extracts, residual solvent(hexane) was detected ginseng extracts treated ethanol mixed with hexane. But extracts that dried after soaked in hexane wasn't detected hexane. Mineral components(Al, Mn, Fe, Cu and Zn) were detected in fine root and 5 types of extracts. The contents of mineral components between fine root and extracts with various extracting conditions were similar, however, extracts that dried after soaked in hexane showed the lower amount in Al, Fe, Pb than the others. In comparison with commercial ginseng ex-tract products(domestic, imported), the distribution pattern of mineral was similar but the contents were a little different.

A Study of Effects of Ilex serrata Thunb Extracts (낙상홍 추출물의 효능에 관한 연구)

  • Lee, Kwang-Soo;Park, Kyung-Sook
    • The Korean Journal of Food And Nutrition
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    • v.29 no.6
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    • pp.946-951
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    • 2016
  • In this study, Ilex serrata Thunb was extracted with 70% methanol and concentrated under reduced pressure to measure its total polyphenol contents; furthermore, we examined the effect of electron donating ability of the various extracts. The extract was fractionated using different solvents such as methylene chloride, ethyl acetate, and methanol to investigate total polyphenol contents and electron donating abilities. The total polyphenol contents were $1,058.59{\pm}85.85{\mu}g\;GAE/mL$ in 70% methanol, $297.29{\pm}29.43{\mu}g\;GAE/mL$ in methylene chloride, $313.28{\pm}9.22{\mu}g\;GAE/mL$ in ethyl acetate, and $837.82{\pm}31.16{\mu}g\;GAE/mL$ in methanol. The total polyphenol contents showed significant differences (p<0.05) between the solvents. The electron donating abilities were $72.93{\pm}0.29%$ for 70% methanol extract, $14.02{\pm}2.01%$ for methylene chloride, $24.05{\pm}1.75%$ for ethyl acetate, and $84.08{\pm}1.95%$ for methanol. The electron donating abilities were significantly different (p<0.05) between the solvents. The two portions of Ilex serrata Thunb extracts obtained from methanol showed significantly relevant results in the total polyphenol contents and electron donating ability, which was higher than the original extract.

Correlation of the Rates of Solvolysis of 1- and 2-Naphthyl Chloroformates Using the Extended Grunwald-Winstein Equation

  • Moon, Doo-Hwan;Seong, Mi-Hye;Kyong, Jin-Burm;Lee, Ye-Lin;Lee, Yong-Woo
    • Bulletin of the Korean Chemical Society
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    • v.32 no.7
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    • pp.2413-2417
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    • 2011
  • The specific rates of solvolysis of 1- naphthyl chloroformate (1-NaphOCOCl, 1) and 2-naphthyl chloroformate (2-NaphOCOCl, 2) have been determined in a wide range of solvents at 2.0 and 10.0$^{\circ}C$. These give a satisfactory correlation over the full range of solvents when the extended (two-term) Grunwald-Winstein equation is applied. The sensitivities (l and m-values) to changes in solvent nucleophilicity ($N_T$) and solvent ionizing power ($Y_{Cl}$) are similar to those reported previously for solvolysis of phenyl chloroformate, which has been suggested to proceed through an addition-elimination mechanism with the addition step being rate determining. For four representative solvents, studies were made at several temperatures and activation parameters determined. These observations were also compared with those previously reported for phenyl chloroformates and naphthoyl chlorides.

Effect of Solvent on Swelling, Porosity and Morphology of Transparent Poly (HEMA)

  • Pathak Tara Sankar;Kim Lae-Hyun;Chung Kun-Yong
    • Korean Membrane Journal
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    • v.8 no.1
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    • pp.67-73
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    • 2006
  • Transparent materials are well known but preparation of transparent poly 2-hydroxyethyl methacrylate {poly (HEMA)} material by varying solvent is a new one and economically reliable. This material is prepared from hydroxyl based monomer HEMA by radical polymerization using benzoyl peroxide (BPO) as initiator and isobutanol, 2-butanol, 1-butanol, hexane and toluene as a solvent. The reaction temperature, time and stirring speed were set at $70^{\circ}C$, 4 hrs and 150 rpm, respectively. The polymer was characterized for functional group by IR spectroscopy. It was observed that the intensity of band at $1637 cm^{-1}$ a characteristic band of C=C stretching disappeared indicating that it was completely consumed after polymerization. It was observed that swelling percentage increases with increase as time passes but after a certain time a constant swelling percentage is achieved. SEM pictures reveals that poly (HEMA) prepared by different solvent shows pore with a distinguishable void up to several micrometers. The BET surface area, cumulative pore volume and average pore diameter is greater in poly (HEMA) prepared by hexane as a solvent compared to other solvents. Poly (HEMA) prepared by 1-butanol as a solvent shows higher glass transition temperature compared to other solvents. Poly (HEMA) prepared by different solvents shows $90{\sim}94%$ light transmission property from light transmission measurement and looks transparent.

Validation of an Extraction Method for the Determination of Airborne MWFs using Alternative Solvents (대체용매를 이용한 금속가공유 측정방법 타당성 평가)

  • Jeong, Jee Yeon;Baek, Nam Won
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.16 no.2
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    • pp.91-100
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    • 2006
  • The purpose of this study was to validate alternative method by using non-carcinogenic, and less toxic solvents than NIOSH analytical method 5524 for measuring the airborne MWFs in workplaces. In laboratory tests, the ETM solvents(mixture of same volume for ethyl ether, toluene, and ethanol) were selected. The alternative method of analyzing MWFs, referred to as the ETM solvent extraction method, showed 0.04 mg/sample as LOD, and 0.15 mg/sample as LOQ. The analytical precision (pooled CV, coefficient of variation) of the ETM solvent extraction method for analyzing the straight, soluble, semisynthetic, and synthetic metalworking fluid was 1.5%, 2.0%, 2.6%, 1.6%, respectively, which was similar to the precision (2.6%) of NIOSH analytical method (NIOSH 0500) for total dust. The analytical accuracy by recovery test, spiked mass calculated as extractable mass, was almost 100%. As the result of storage stability test, metalworking fluid samples should be stored in refrigerated condition, and be analyzed in two weeks after sampling. The 95% confidence limit of the estimated total standard error for the ETM solvent extraction method for analyzing the straight, soluble, semisynthetic, and synthetic metalworking fluid was ${\pm}12.6%$, ${\pm}12.5%$, ${\pm}14.0%$, and ${\pm}13.6%$, respectively, which satisfied the OSHA sampling and analytical criteria.