• 제목/요약/키워드: solvent extraction gravimetric method

검색결과 4건 처리시간 0.021초

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

  • 정지연;백남원
    • 한국산업보건학회지
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    • 제16권2호
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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.

Sulfa제-Cu착화합물의 형성에 관하여 II Spectrophotometry 에 의한 Copper Sulfa-Drug Complex 의 화학조성결정 (Studies on the Formation of Copper Complexes of Sulfa-Drug II.Study on Chemical Constisuent of Copper Sulfa-Drug Complex by Continuous Variation Method.)

  • 이왕규
    • 약학회지
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    • 제8권4호
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    • pp.96-99
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    • 1964
  • In the previous study, the composition ratios of the Cu-sulfa drugs complexes determined by gravimetric and solvent extraction method reported. In this paper, the continuous variations method has been used to know whether the complexes are simple complexes or chelates, and to recertify the composition ratios of the complexes at pH 7-8. It has been certified that the ratio of $Cu^{+2}$ ion to sulfa drugs in 1:2 from the result of this experiment.

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Sulfa제-Cu 착화합물의 형성에 관하여 (Studies on the formation of Copper Compelxes of Sulfa-Drug.)

  • 이왕규
    • 약학회지
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    • 제7권1호
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    • pp.13-17
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    • 1963
  • The purpose of this work is to investigate the molar ratio, the precipitation condition and the color of copper sulfa-drugs complexes. The colors of the complexes are observed at every precipitation condition is obtained as pH 7-9. The determination of the molar ratio of complexes is able to be carried out by way of gravimetric method and solvent extraction method. The molar ratios of sulfa-drugs and copper in identified complexes are 2:1 when utilizing both methods.

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혼합제제중 Methylephedrine Hydrochloride와 Ephedrine Hydrochloride의 분리정량에 관한 연구 (Study on Isolative Determination Methylephedrine Hydrochloride and Ephedrine Hydrochloride in the Mixed Preparation)

  • 고인석
    • 생약학회지
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    • 제1권3호
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    • pp.93-99
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    • 1970
  • There have been reported by several workers for the isolation and determination of the amine derivatives as Metbylephedrine Hydrochloride and Ephedrine Hydrochloride adopting neutralization method, steam distillation method, non-aqous titration method, ion-exchange resin method, titration method after acetylation, colorimetric method, gravimetric method, iodine titration method and gas chromatography. Those methods mentioned in above, can be practically applied for the sample which is not mixed one mith the other amine compounds. Presently, it has not shown on the isolative determination of the mixed sample of amine derivatives. In this paper, it is discussed on the isolative determination of Methylephedrine Hydrochloride as the tertiary amine compound and Ephedrine Hydrochloride as the secondary amine compound. According to the results of the experiment, it could be summarized as follows: 1. There is no time-variation on the color reaction of Methylephedrine Hydrochloride and Ephedrine Hydrochloride with the color reagent, bromcresolgreen. And Methylephedrine Hydrochloride and Ephedrine Hydrochloride, respectively, can be determined spectrophotometrically by means oft his color reaction. 2. For the isolation of Methylephedrine Hydrochloride and Ephedrine Hydrochloride from the mixed sample, Methylephedrine Hydrochloride can be eluted by chloroform, while Ephedrine Hydrochloride by the mixed solvent of chloroform and ethylalcohol (2:1), from the celite column adsorbed at pH6.4 followed by extraction with ether undersodium hydroxide alkali re action. 3. When the sample is mixed with quinine hydrochloride, dihydrocodeine bitartate, and noscapine, these mixed compounds can be eliminated by means of stram distillation. 4. When the sample is mixed with chlorpheniramine maleate, dextromethorphan hydrobromide and diphenhydramine hydrochloride, the mixed compounds can be eliminated by means of steam distillation and celite adsorption column chromatography, In conclusion, the isolative determination method for Methylephedrine Hydrochloride and Ephedrine Hydrochloride studied in this paper, indicates with the excellent reproducibility and accuracy.

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