• YAKHAK HOEJI
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• v.32 no.6
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• pp.415-419
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• 1988

A rapid and simple method for the determination of pentoxifylline and its major metabolite, metabolte(I) in plasma was examined by HPLC. For the purification and enrichment of drug from plasma, solid-phase extraction was examined using Sep-pak C18 cartridge. The effectiveness of test method was proved by monitoring of the rat after oral administration of pentoxifylline in a dose of 40mg/kg.

• YAKHAK HOEJI
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• v.33 no.3
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• pp.156-160
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• 1989

A gas-chromatographic determination method of thiamin which use a quantitative cleavage of thiamin to 4-methyl-5-(2-hydroxyethyl)thiazol [I] and solvent extraction of the analyte prior to GC injection was modified. A column chromatographic procedure using a reversed phase, high capacity solid phase cartridge was applied to the clean-up of the analyte. Thiazol derivative[I] was quantitatively recovered upon the column method. Acetanilide, an internal standard, has a good recovery through the analytical procedure. The method has analytical precision of 2% or less in the coefficient of variation.

• Proceedings of the KIPE Conference
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• 2018.07a
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• pp.440-441
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• 2018

본 연구에서는 핫플레이트를 균일한 표면 온도로 가열시키기 위한 카트리지 히터의 설계를 시도하였다. 이를 위하여 1. 표면 전력밀도 및 전열선 전력밀도에 따른 발열온도 측정 실험 2. 카트리지 히터의 분할 영역과 전열선 권선 비율에 따른 온도 측정 실험을 실시하여 온도분포형 카트리지 히터의 설계 사양을 선정하였다. 또한 이렇게 설계한 카트리지 히터를 직접 제작하여 기존의 표준형 카트리지 히터와의 성능 비교 측정 실험을 실시하여, 본 연구에서 제시한 방법으로 제작한 카트리지 히터의 표면 온도 균일도가 우수함(표면 온도차 ${\leq}1.25[^{\circ}C]$)을 증명하였다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.12
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• pp.938-944
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• 2008

The boiling heat transfer was experimentally investigated for the PF-5052 sprays impacting a square heated test surface in a downward direction. Full cone spray nozzles were employed for the spray cooling experiment, and experiments were made under the test conditions of Q=$3.32{\time}10^{-6}{\sim}\;12.98{\time}10^{-6}m^3/s$, ${\Delta}T_{sub}=5{\sim}25^{\circ}C$. Also, heat transfer measurements were made using the copper block of $10{\time}10mm^2$ test area heated by nine cartridge heater. From the experimental results, correlation between the Nusselt number and Reynolds number based on droplet-flow-rate was developed. The correlation shows good predictions with ${\pm}30$ % error for PF-5052.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.12
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• pp.633-638
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• 2001

The paper presents the fabrication and test of a micro scent injector module. A micro scent injector module consists of an injector fabricated by micromachining, a scent cartridge and a controller. If a scent injection signal triggers the controller, it heats the scent liquid in the injector chamber and a scent liquid is vaporized. The increased vapor pressure opens a normally closed boss valve, and the scent vapor is injected through the opened nozzle. The liquid volume injected by the fabricated module is about $1\muell$ for one second at 2 W.

• Journal of the Korean Society of Safety
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• v.11 no.1
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• pp.84-89
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• 1996

The adsorption characteristics of active carbon used as a cartridge filler of organic vapor respirator were examined by humidity, particle size, challenge concentration and specific surface area. As a result, the 1% breakthrough time of Carbon Tetrachloride($CCl_4$) was decreased with increase of relative humidity, challenge concentration and particle size (0.6～2.0mm) of active carbon. The adsorbed amount of $CCl_4$ was about 1. 1mg/$m^2$ at RH 40% and 0. 5mg/$m^2$ at RH 80% . However in the case of prehumidified active carbon, humidity did not affected to 1% breakthrough time up to RH 40%.

• Korean Journal of Veterinary Service
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• v.25 no.3
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• pp.221-227
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• 2002

This study was carried out to confirm analytical method of residual macrolides in livestock products by LC/MS. 1. Macrolides were analyzed by LC/MS on XTerra C$\sub$18/ column with 0.1% TFA(trifluoroacetic acid)-methanol in a gradient mode as mobile phase, and that were identified by positive chemical ionization with selective ion monitoring at 50～1000 mass range. 2. Residual macrolides were extracted from tissue with acetonitrile, and the extract is purified with a Sep-pak C$\sub$18/ cartridge, and elute macrolides with 0.1M methanolic ammonium acetate. 3. The procedure confirms the presence of each macrolide at 50$\mu\textrm{g}$/kg in spiked sample.

• Toxicological Research
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• v.12 no.2
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• pp.163-169
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• 1996

The focus of this study was to investigate the suitable analytical methods for measurement of sulfamerazine and its metabolite in shrimp hepatopancreas and tail tissue, in addition to the methods for the optimization of solid-phase extraction cartridge conditions and the elucidation of sulfamerazine concentrations in aqueous buffer using HPLC with UV and EC detectors. Compared with UV detector the EC detector appears to be 10 times more sensitive than that of the UV detector. After the shrimp was exposed to 10 ppm sulfamerazine, the accumulation levels of sulfamerazine and its metabolite in tail tissue, which is edible portion, were considerably lower than 0.1 ppm. The data indicate that sulfamerazine continues to be a candidate for use at levels of sulfamerazine concentration used in aquaculture of shrimp.

• The Korean Journal of Food And Nutrition
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• v.12 no.4
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• pp.364-369
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• 1999

The changes of phenolics in Korean apple(Fuji) during maturation were analyzed by HPLC and spec-tropotometry. The phenolics were separated through C18 Sep-Pak cartridge in series. Chlorogenic acid caffeic acid p-coumaric acid ferulic acid and ($\pm$)-catethin were indentified by the direct comparison with authentics on HPLC. The total amounts of phenolics were determined by Folin-Dennis's method. The amounts ranged from 70.19mg% to 97.57mg% of wet basis. The concentration of phenolics in apple decreased during the early stage of development and then remained relatively constant during matu-ration .

• Food Science of Animal Resources
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• v.21 no.1
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• pp.64-70
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• 2001

The extraction procedure and HPLC condition were modified to analyze the residues of oxytetracycline, sulfamethoxazole and chloramphenicol in pork, simultaneously. The antibacterial agents in pork were extracted with 0.02M EDTA-Mcilivine buffer:ethanol:acetonitrile (5:3:2). After the removal of fat with n-hexane, the extracts were evaporated and purified with Sep-pak $C_{18}$ cartridge column using 0.01M oxalic acid 0.1% (v/v) triethylamine (TEA) in acetonitrile. The peak of antibacterial agents was detected with $\mu$ Bondapak C18 column, UV detector (280nm) and 0.01M oxalic acid: methanol: acetonitrile (7.5:2.0:0.5). Detection limits for three antibacterial standards were 0.03 ppm. Calibration curves were linear between 0.03 and 2.0 ppm (R$^2$>0.999). When spiked the level of 1.0 ppm of oxytetracycline, sulfamethoxazole and chloramphenicol into meats, the recoveries from meats were 77.3%, 79.7% and 59.3%, respectively. These results showed that the modified extraction method provided good analytical resolution and the recoveries of the above antibacterial agents in meats.