• 한국전산유체공학회:학술대회논문집
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• 2008.08a
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• pp.51.6-51.6
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• 2008

• Bulletin of the Korean Chemical Society
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• v.20 no.7
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• pp.843-845
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• 1999

• Bulletin of the Korean Chemical Society
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• v.15 no.11
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• pp.945-949
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• 1994

Mixtures of cyano complexes of palladium(II) and platinum(II) were separated by capillary electrophoresis using a fused silica capillary as a separation column and 30 mM phosphate buffer (pH 7) containing 15 wt. % acetonitrile as a running buffer. By virtue of the high ionic mobilities of the negatively charged cyano complexes of Pd(II) and Pt(II), they were separated using a cathodic injection and anodic detection scheme. The metal complexes eluted through the capillary were detected by direct UV absorption at 214 nm. A linear relationship between peak area and concentration was obtained for both ions and the detection limit was lower than $10^{-14}$ mole. The proposed method was applied to real sample, e.g., anode slime obtained from an electrolytic copper refinary, as a method for the simultaneous determination of palladium and platinum.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2224-2228
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• 2012

This study describes the ability of capillary electrochromatography (CEC) for the determination of imidacloprid and carbendazim in tomato samples. A novel liquid crystal crown ether modified hybrid silica monolithic column was synthesized, characterized and developed as separation column for the first time. Baseline separation of imidacloprid and carbendazim could be achieved using a mobile phase containing 90% (v/v) 20 mmol/L phosphate buffer (pH 7.0) and 10% (v/v) acetonitrile. The matrix matched calibration curves were linear with correlation coefficient $r^2$ > 0.9998 in the range of 0.20-10.00 mg/L. The limits of detection for imidacloprid and carbendazim were 0.061 and 0.15 mg/kg, respectively, which were below the maximum residue limits established by the European Union as well as Codex Alimentarius. Average recoveries for imidacloprid and carbendazim varied from 101.6-108.0% with relative standard deviations lower than 6.3%. This method was applied to the analysis of tomatoes collected from local markets.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.2
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• pp.176-178
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• 1990

The essential fatty acid composition of evening primrose seed at 3 natural habitats in Korea was investigated by means of capillary column gas-chromatography. The content of essential fatty acid components was palmitic acid 6.19-6.73%. stearic acid 1.84-1. 99%, oleic acid 6.73-9.10%. linoleic acid 74.41-75.53%. Particularly. gamma-linolenic acid (GLA) which is a precursor of prostaglandin was 9.14% in Cheong-ju. 9.32% in Che-cheon and 8.31% in An-dong. Based on the GLA content evening primroses in Korean natural habitats seem to be very promising and useful for GLA production.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.1
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• pp.25-32
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• 1994

Arylmethyl halides(benzyl chloride, BZYC; benzal chloride, BZYA; benzotrichloride, BZTC) and related compounds(benzyl alcohol, BZYA; benzoyl chloride, BZOC) were determined by GC using capillary column. Detailed results are as follows. 1. Stability In methanol benzotrichloride slowly transferred to benzoyl chloride by hydrolysis(ca. 7.5% for 5 days), but the others were stable. Therefore, benzotrichloride solution should be prepared just before analysis. 2. GC analysis Tenax-GC was used to absorbent and desorption solvents were $CCl_4$ and MeOH. Arylmethyl halides were analyzed within 7.5min without interference with related compounds. The calibration curve(ca. 15-80 ppm in soln), repeatability(n=10) and the desorption efficiency were good. Limit of detection by NIOSH method was about 0.003 ppm for arylmethyl halide, respectively. To analyze arylmethyl halides and related compounds in working places GC using capillary column is anticipated to be used effectively.

• Archives of Pharmacal Research
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• v.5 no.2
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• pp.71-77
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• 1982

Improvements in the analytical methodology used in the gas chromatographic/mass spectral analysis of phenolic compounds from cigarette smoke are described. For the direct analysis of crude samples, pyridine extraction and the glass capillary column GC was used for the separation of phenolics as trimethylsilyl derivativatives. The separations of cigarette smoke on Carbowax 20M and SE-54 wall coated open tubular columns are given. Improved methodology for the routine quantitation of the identified components using the computer-controlled multiple ion selection technique of MS presented. Considerations pertaining to routine analyses of a multitude of complex smoke samples are also discussed.

• Journal of the Korean Chemical Society
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• v.31 no.3
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• pp.244-249
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• 1987

Liquid-solid extraction technique was applied to enrich volatile free acids (VFAs) from aqueous matrices. Chromosorb P was found to be an efficient solid sorbent. The unionized VFAs could be quantitatively recovered from the Chromosorb P column with ether while interfering watermiscible components were retained in the adsorbed water on the surface of Chromosorb P. The method of simple and efficient isolation-enrichment of VFAs, followed by the quantitative analysis employing stainless steel capillary column coated with Carbowax 20M containing phosphoric acid has been applied to the determination of VFAs in several aqueous samples.

• Analytical Science and Technology
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• v.8 no.4
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• pp.739-744
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• 1995

The two main methods to prepare water samples for analyzing volatile organic compounds(VOC's) were investigated. One is the purge and trap(PT) method and another is the head space(HS) sampling method. Both methods were effective to transfer the low boiling point components from the water sample onto the capillary column. The cryo-focusing at the top of the main capillary column was an effective way to obtain the sharpness of the chromatographic peaks but could be avoided when a semi-wide bore column was used. The recovery from the same amount of the sample was better in PT than in HS but a larger sample volume in HS method could compensate the lower efficiency. Therefore PT is suitable to the analysis of drinking water where the very low concentration must be determined. HS is suitable to waste water analysis because of the easiness of the operation. The repeatability was good and similar in both methods. For the contamination of the former sample, both methods were tough and could be used without any problems. The matrix effect which could change the equilibrium parameters in HS method was find negligible in many components. The actual samples such as tap water and river water were analyzed with both methods concerning 16 components regulated in Korea.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.18-22
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• 1994

This study was designed to investigate the method of the simultaneous determination of water-soluble vitamins (thiamine, ascorbic acid, riboflavin, folic acid, cyanocobalamine, pyridoxin, nicotinic acid) by free soloution capillary electrophoresis. Factors affecting on the separation were pH of the buffer, applied voltage and temperature. On-column detection at 254 nm allowed accurate and reproducible determination of these compounds. All these compounds were separated within ca. 8 min with fused silica capillary at 20 kV.