• 한국식품과학회지
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• 제20권1호
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• pp.34-39
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• 1988

여러가지 육가공품(肉加工品)중 특정 단백질 원료의 첨가여부를 판정하여 변조식품(變造食品)을 검출하는 한 방법으로서, 각종 육류단백질, non-meat protein, 어육(魚肉)가공품을 대상으로 disc SDS-Poly acrylamide gel electrophoresis의 사용 가능성을 실험하였다. Total protein fraction에 대한 전기영동 결과 복잡하고 많은 band를 보여 각 시료에 고유한 특성을 찾아보기 어려웠다. Low salt-soluble protein fraction에서는 total protein fraction 에서 보다 band 수가 상당히 감소함을 보였고 각 단백질 원료에 대하여 보다 고유한 band pattern을 나타내었다. Acetone-insoluble protein fraction 에서는 non-meat protein의 경우 육류단백질과 상당히 다른 경향을 나타내었고. 소세지 원료의 가열처리에 의하여 단백질의 band수와 양이 감소하였다. 따라서 적당한 단백질 추출조건(抽出條件)을 설정하여 전기영동을 실시하면, 특정(特定) 단백질을 첨가한 변조식품의 검출이 가능해질 것으로 생각된다.

• 한국환경과학회지
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• 제1권2호
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• pp.71-79
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• 1992

수계내 저질에 대한 구리 및 카드융의 분배 특 성을 검토하기 위하여 선택적 연속추출법에 의해 실험한 결과 다음과 같았다. 저질에 분배된 구리는 pH의 변화에 따라 carbo¬n nate 상과 exchangeable/adsorbed 상이 영향을 많이 받았으며 카드륨은 carbonate 상이 영향을 많이 받았다. 그리고 NTA와 EDTA가 함께 존재할 때 구리와 카로융 모두 carbonate 상과 결합한 것이 가장 많이 해리되어 수중으로 이동하였다. 저질과 결합한 금속량과 평형농도 사이의 구리와 카드륨의 총괄적인 분배계수는 구리가 8.361이었 으며 카드륨이 0.497이었다. 저질내 각 고형상에 분배된 크기를 분배계수로 나타내면 구리의 경우는 carbonate, organic matter, exchangeable/adsorbed, manganese oxides 그리고 iron oxides 차례로 컸으며, 카드뮴의 경우는 exchangeable/adsorbed, carbonate, manganese oxides, organic matter 그리고 iron oxides 차례로 컸다. organic matter 상은 구리와는 달리 카드륨에서는 분배에 크게 기여하지 않았다.

• Biomolecules & Therapeutics
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• 제15권2호
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• pp.123-126
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• 2007

A sensitive, simple and highly selective liquid chromatography method of determination for extraction of pseudoephedrine hydrochloride from Allegra D tablet was developed. The chief benefit of the present method is the minimal sample preparation, as the procedure is only filtering through pore syringe filter. Two drugs (pseudoephedrine hydrochloride, fexofenadine) were separated on a C$_{18}$ column and analyzed by high performance liquid chromatography (HPLC). The method had a chromatographic run time of 8.0 min. 1 ml of pseudoephedrine hydrochloride solution (1 mg/ml) was filtered through 0.22 um pore syringe filter. 50 ul of filtering solution was injected to HPLC pump and we knew the retention time (1.85 min) of separating of pseudoephedrine hydrochloride using UV detector at 280 nm. We used C$_{18}$ column (4.6 mm${\times}$250 mm), mobile phase solution (<0.05 mol/L NaH$_2$PO$_4$, 2 ml/L H$_3$PO$_4$>/CH$_3$CN / sodium dodesyl sulfate = 60 ml / 40 ml / 1 g). We separated psedoephedrine hydrochloride at run time of 1.85 min from Allegra D tablet solution (1 mg/ml) filtered through 0.22 um pore syringe filter using UV detector at 280 nm. Flow rate was set at 1.0 ml/min and the column temperature was set at 40$^{\circ}C$. Psedoephedrine hydrochloride solution (1 mg/ml) separated from Allegra D tablet was filtered through 0.22 um pore syringe filter and injected 50 ul. We confirmed the peak of psedoephedrine hydrochloride at same retention time and the separating solution was freeze-dried. In conclusion, A simple isocratic reverse-phase HPLC method has been developed that provides excellent separation of pseudoephedrine from Allegra D tablet.

• Journal of Microbiology and Biotechnology
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• 제18권2호
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• pp.248-254
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• 2008

Candida magnoliae, an osmotolerant and erythritol producing yeast, prefers D-fructose to D-glucose as carbon sources. For the investigation of the fructophilic characteristics with respect to sugar transportation, a sequential extraction method using various detergents and ultracentrifugation was developed to isolate cellular membrane proteins in C. magnoliae. Immunoblot analysis with the Pma1 antibody and two-dimensional electrophoresis analysis coupled with MS showed that the fraction II was enriched with membrane proteins. Eighteen proteins out of 36 spots were identified as membrane or membrane-associated proteins involved in sugar uptake, stress response, carbon metabolism, and so on. Among them, three proteins were significantly upregulated under the fructose supplying conditions. The hexose transporter was highly homologous to Ght6p in Schizosaccharomyces pombe, which was known as a predominant transporter for the fructose uptake of S. pombe because it exhibited higher affinity to D-fructose than D-glucose. The physicochemical properties of the ATP-binding cassette transporter and inorganic transporter explained their direct or indirect associations with the fructophilic behavior of C. magnoliae. The identification and characterization of membrane proteins involved in sugar uptake might contribute to the elucidation of the selective utilization of fructose to glucose by C. magnoliae at a molecular level.

• 공업화학
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• 제8권4호
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• pp.679-684
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• 1997

석유화학공업에서 사용된 유동접촉분해(FCC) 폐촉매의 주성분은 Si와 Al이며, 그외에 Fe, Zn, Ti 등의 기본금속과 알칼리금속 및 Ce, Nd, Ni, V 등의 희유금속이 함유되어 있다. $0.25mo1/dm^3-H_2SO_4$를 침출제로 폐촉매를 침출하였을 때 Ce가 640, Nd가 310, 그리고 V가 $450mg/dm^3$ 함유된 pH 1.0의 침출액을 얻었고, 아미노인산형 킬레이트수지에 의하여 Ce와 Nd를 선택흡착시킨 후, $4.0mol/dm^3-HCl$로 용리시켜 $1.2g/dm^3$의 Ce와 $0.75 g/dm^3$의 Nd 농축액을 얻었다. 농축액을 다시 옥살산 침전 및 공기산화법으로 처리하여 Ce와 Nd의 분리가 가능하였으며, 염소이온 공존하에 추출제 TOPO를 이용한 용매추출법으로 V와 Al을 각각 분리시켜, FCC 폐촉매로부터 순도가 99%인 Ce, Nd 및 V의 분리정제가 가능하였다.

• 대한전자공학회논문지SP
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• 제41권5호
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• pp.165-173
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• 2004

수리형태학을 이용한 영상분할의 분할 성능은 우수하지만 너무 많은 영역으로 분할되는 경향이 있는데, 후처리 과정을 사용하지 않고 이러한 문제를 해결하기 위해서는 마커 추출에 사용되는 구조요소의 크기를 증가시켜야 한다. 그러나 구조요소의 크기가 너무 크면 영역의 경계를 제대로 분리해낼 수 없기 때문에 본 논문에서는 영상분할의 성능 개선을 위해 수리형태학적 구조요소를 선택적으로 적용하였다. 이를 위해 평균국부분산과 영상의 기울기를 이용하여 입력 영상을 질감 영역, 에지 영역, 단순 영역으로 분류하였다. 그리고 각 영역별로 구조요소의 크기를 선택적으로 적용하여 영상이 과분할 되는 원인을 제거하였다. 실험 결과, 화소의 밝기 값이 비슷한 영역에 대해서도 영상이 잘 분할됨을 확인하였고 기존의 방법보다 질감 영역 및 에지영역을 정확하게 찾아냄을 확인할 수 있었다.

• 원예과학기술지
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• 제32권4호
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• pp.558-570
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• 2014

This study was conducted to compare the volatile flavor compounds found in the leaves of 15 taxa of Korean native Chrysanthemum species. The volatile flavor compounds from the taxa were collected using a simultaneous steam distillation and extraction technique and were analyzed using gas chromatography/mass selective detector (GC/MSD). A total of 45 volatile flavor compounds were identified with six functional groups: 14 alcohols, 4 ketones, 19 hydrocarbons, 5 esters, 2 acids, and 1 aldehyde. The main functional group in 15 taxa of Chrysanthemum species was alcohols, accounting for 28.7% of volatile flavor compounds, followed by ketones (21.2%) and hydrocarbons (13.2%). Camphor, which is known for its antimicrobial properties, was the most abundant volatile compound (30%) in C. zawadskii ssp. latilobum and var. leiophyllum. In particular, C. indicum subspecies and C. boreale contained ${\alpha}$-thujone, which has outstanding anti-bacterial, anti-cancer, anti-inflammatory, anti-ulcer, and anti-diabetic efficacies. C. indicum var. albescens could be used in perfumes, since it showed 21 times more camphene than C. indicum. In addition, C. indicum var. acuta contained a fairly high content of 1,8-cineole, which has an inhibitory effect on mutagenesis. C. lineare contained only pentadecanoic acid compounds, whereas other taxa hexadecanoic acids. Overall, the Korean native Chrysanthemum species had considerable variation in volatile flavor compounds in their leaves. This study provides a good indication of specific potential use for various applications.

• Biomolecules & Therapeutics
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• 제15권4호
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• pp.266-272
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• 2007

A rapid analytical method was developed to quantify very long-chain fatty acids (VLCFAs, C22:0, C24:0, C26:0) in human plasma with good sensitivity and specificity using tert-butyldimethylsilyl (TBDMS) derivatization and stable isotope GC-MS selective ion monitoring (GC-MS/SIM). Two-hundred and fifty ${\mu}L$ of plasma was fortified with deuterated stable isotope internal standards (d3-C22:0, d3-C24:0, d3-C26:0) and standard mixtures of chloroform and methanol, and then extracted with hexane and acetonitrile. To upper layer of liquid-liquid-extraction, N-(t-Butyldimethylsilyl)-N-methyltrifluoroacetamide was added and then heated to $60^{\circ}C$ for 30 min to produce the TBDMS derivatives. Derivatives of VLCFAs were analyzed by GC-MS/SIM. Calibration curves showed a linear relationship for the target compounds in the concentration range of $10^{-4}{\sim}2{\times}10^3\;{\mu}g/mL$ with the correlation coefficient ranging from 0.996 to 0.999. The limit of quantification for the plasma was $10^{-4}{\sim}2{\times}10^{-4}\;{\mu}g/mL$ (S/N=3). When applied to the plasma specimens of patients with peroxisomal disorder, X-linked adrenoleucodystropy (ALD, Mckusick 202370), the method clearly differentiated normal subjects from ALD patients. The C24:0/C22:0 and C26:0/C22:0 ratios were significantly elevated in the plasma of patients with X-linked ALD compared to normal subjects. The new developed method might be useful for a rapid and sensitive diagnosis of X-linked ALD and other peroxisomal disorders.

• 한국지하수토양환경학회지:지하수토양환경
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• 제23권1호
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• pp.54-62
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• 2018

This paper is aimed at source tracking of soil heavy metal contamination at a site established by reusing construction wastes. The soil heavy metal concentration at the study site peaked at a depth range of 5-10 m. Column studies were conducted to investigate the possibility of the contamination scenario of infiltration of stormwater carrying heavy metals of ground origin followed by selective heavy metal accumulation at the 5-10 m depth range. Almost all amount of lead, zinc, cadmium, and nickel introduced to the columns each packed with 0-5 m or 5-10 m field soil were accumulated in the column. The very poor heavy metal mobility in spite of the weak association of the heavy metals with the soil (characterized by a sequential extraction procedure) can be attributed to the high pH (10-11) of the construction wastes. From the results, the heavy metal contamination of the subsurface soil by an external heavy metal source was determined to be very unlikely at the study site. The column study applied in the current study is expected to be a useful methodology to present direct evidence of the contaminant source tracking at soil contamination sites.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.48-48
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• 2011

We have developed a chemically-driven top-down approach using vapor phase HCl to form various GaN nanostructures and successfully demonstrated dislocation-free and strain-relaxed GaN nanostructures without etching damage formed by a selective dissociation method. Our approach overcomes many limitations encountered in previous approaches. There is no need to make a pattern, complicated process, and expensive equipment, but it produces a high-quality nanostructure over a large area at low cost. As far as we know, this is the first time that various types of high-quality GaN nanostructures, such as dot, cone, and rod, could be formed by a chemical method without the use of a mask or pattern, especially on the Ga-polar GaN. It is well known that the Ga-polar GaN is difficult to etch by the common chemical wet etching method because of the chemical stability of GaN. Our chemically driven GaN nanostructures show excellent structure and optical properties. The formed nanostructure had various facets depending on the etching conditions and showed a high crystal quality due to the removal of defects, such as dislocations. These structure properties derived excellent optical performance of the GaN nanostructure. The GaN nanostructure had increased internal and external quantum efficiency due to increased light extraction, reduced strain, and improved crystal quality. The chemically driven GaN nanostructure shows promise in applications such as efficient light-emitting diodes, field emitters, and sensors.