• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.541-544
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• 2003

Chloride diffusivity is one of the important properties of concrete affecting the durability of a structure. The diffusivity for porous materials is determined conventionally by immersion in a solution. However, this method is complicate and time-consuming, often requiring months or years to obtain results. Thus, the application of colorimetric method to estimate the apparent diffusivity of chloride ion was verified in this study. The result reveals that the apparent diffusivity of chloride ion can be predicted to use colorimetric method. Additionally the colorimetric method is capable to predict the profile of chloride ion.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1995.10a
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• pp.115-117
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• 1995

This paper describes the O.T aging analysis by non-destructive electrical and UV/visible method. Non-destructive diagnosis method is tan8 test. Also the new method of the aging analysis, UV/visible method was introduced in this paper and compared with the non-destructive electrical method. The UV/visible test could be useful method for the O.T aging electrical diagnosis such as non-destructive electrical method.

• Journal of Nutrition and Health
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• v.17 no.1
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• pp.31-40
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• 1984

A new microassay was proposed for the determination of serum thiobarbituric acid(TBA) value greatly enhanced by ferric ion under anaerobic condition. One ${\mu}mole$ of $FeCl_{3}$ per $10{\mu}l$ of serum was added to the TBA reaction mixture containing serum protein precipitate. The reaction mixture was heated on boiling water-bath for 50min under $N_{2}$ flushing. The sensitivity of this assay was greatly enhanced by 40 times comparing with that of Yagi's method (1976). In favour of the enhancement, this test could be measured by colorimetry or spectrophotometry with the sample size of $10-20{\mu}l$ serum. The sensitivity and reproducibility were also improved by means of partial dehydration of the butanol extract with $(NH_{4})_{2}SO_{4}$ salting-out. Serum TBA values of healthy human at different age groups were determined by this proposed method.

• Applied Biological Chemistry
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• v.43 no.2
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• pp.100-105
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• 2000

Anionic peroxidases (POD) were isolated from Korean radish (Raphanus sativus L.) root by using fractionation with $(NH_4)_2SO_4$ and CM-cellulose ion exchange chromatography and used as the colorimetric enzyme for glucose determination. The chromogen used in this work was o-tolidine or 4-aminoantipyrine/diethylaniline (4AA/DEA) and the colored products were measured at 630 nm. Korean radish anionic POD showed much better colorimetric reaction of glucose determination with 4AA/DEA than with o-tolidine. The r values of calibration curve for glucose determination by o-tolidine and 4AA/DEA were 0.9983 and 0.9963, respectively. In order to compare the reactivity for substrate oxidation by Korean radish POD and horseradish POD, the Km values against o-dianisidine and guaiacol were measured. Korean radish POD had about 40 fold higher affinity for o-dianisidine and 2 fold higher affinity for guaiacol as revealed by Km values. These results showed that Korean radish POD could be developed as the colorimetric diagnosis reagent for glucose determination with high sensitivity.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.120-120
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• 2017

최근 국내 소비자들의 안전한 음식과 환경문제에 대한 관심이 높아지면서 재배작물과 경작지 토양의 물리 화학적 특성 등에 맞추어 적정 시비 및 재배관리를 적용하는 정밀농업이 시도되고 있다. 정밀농업은 농약 및 비료 등의 양을 적절하게 사용하여 생산 비용을 절감할 수 있으며, 과다사용을 막아 환경오염을 줄일 수 있다. 현재 토양의 수분, EC, pH등과 같은 항목은 신속하고 간단하게 분석이 가능하지만 토양의 필수 원소인 N, P, K 성분을 분석하는 제품은 상용화 되지 않았거나 가격이 비싸 일반 농가에서는 사용이 어렵다. 특히, 토양의 인을 현장에서 분석하기 위한 연구가 많이 수행되고 있으나 실제로 현장에서 사용되는 경우 또한 없는 상황이다. 일반적으로 토양에 포함되어 있는 인을 측정하기 위해서 많은 실험실에서는 이화학적 분석법을 사용하고 있다. 하지만 이 분석법은 오랜 시간과 전문적인 인력이 필요하며 주변 환경변화에 민감하여 실시간으로 분석하기에는 어렵다고 한다. 따라서 본 연구에서는 현장에서 실시간으로 토양의 인을 분석하기 위해 반자동 분석시스템을 제작하고 이를 검증하고자 하였다. 이전 연구에서 현장 토양을 이용한 신속측정법의 가능성($R^2>0.7$)을 확인하여 이 분석법을 바탕으로 반자동 분석시스템을 제작하였고 표준결과 값의 약 70% 이상의 수준을 목표로 하였다. 진주 지역의 현장 토양 20개 샘플과 반자동 침출 장치, 여과 장치, 발색 장치 그리고 통합 반자동 시스템을 이용하여 분석한 후 표준 분석 결과와 비교하였을 때 $R^2$ 값이 각각 0.985, 0.817, 0.893, 0.837로 약 70% 이상의 수준을 달성하였다. 추후, 반자동 토양 인 신속측정시스템을 완전 자동화 시스템으로 개발하고 주행 장치를 부착시켜 현장에서 실시간으로 원하는 위치의 인을 측정 할 수 있을 것으로 판단된다.

• Journal of the Korean Chemical Society
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• v.41 no.5
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• pp.256-265
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• 1997

A rapid and sequential method was studied, which can determine nitrite, nitrate and ammonium ion in soil or water samples with flow injection analysis. Geometric factors including injection volume, length of the reaction coil and flow rate of carrier solution were investigated prior to sample measurement. Nitrite was determined at 540 nm by Griess reaction producing azo dye between N-(1-naphthylethylenediamine dihydrochloride) and sulfanilamide. Nitrate was also measured under the help of reduction mechanism toward nitrite with hydrazine. Ammonium was analyzed at 440 nm with Nessler's reagent. At the optimum condition, the detection limit(S/N=3) has been shown 0.1 ㎍/mL N(NO2-), 0.4 ㎍/mL N(NO3-) and 0.3 ㎍/mL N(NH4+) respectively. The results measured by colorimetry, ion chromatography and FIA were compared showing 80%-125% reasonable match each other. Injection throughput rate could be performed better than 30 times per hour.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.158-163
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• 1991

It is evident that an elevation of airway albumin excreation rate without clinical proteinuria strongly predicts a later progression on diabetic renal disease. So we studied the correation between Microalbumin checkly RIA & Mitral-Test$^{(R)}$. We collected urine between 08 : 00 h and 08 : 00 h next day and then checked microalbuminuria by radioimmunoassay method and Mitral-Test$^{(R)}$ The results are as follows : 1. There was significant correation between microalbuminuria checked by RIA & Micral-Test$^{(R)}$ 2. There was poor correations between diabetes duration or HV-A1c and maximal change in albumin excreation rate. 3. So we conclued that Micral-Test$^{(R)}$ can be used in laboratory instead of RIA.

• Applied Biological Chemistry
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• v.19 no.4
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• pp.233-242
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• 1976

In this paper, new methods for the determination of the total and the individual saponin glucosides were proposed. One of them was a colorimetric method following Two-dimensional Thin layer chromatography. And the method employing Thinchrograph TFG-10 or Densitorol DMU-33C followed the separation of the saponins by means of a preparative thin layer chromatography. In accordance with the density of the chromatogram of each saponin, Thinchrogram or Densitogram of the individual saponin fraction was plotted and determined.

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.14-21
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• 1982

Analytical methods for residues of six N-methylcarbamate insecticides were investigated to compare the minimum detectability, recovery from several crops and feasibility of multiple residue analysis. Those methods studied in this work included spectrophotometry by diazotization and gas chromatography by N-trifluoroacetylation(TFA), pentafluorobenzylether(PFB) and dinitrophenylether (DNP) derivatization. Maximum absorbed wavelength of the diazotized MIPC, XMC, BPMC, propoxur and carbofu ran was around 460 ㎚, while that of carbaryl recorded 510 ㎚. Recovery from brown rice and apple by diazotization method ranged from 80 to 120% and minimum detectable limits were 0.03 to 0.05 ppm in 50 g of the sample. Minimum detectability of PFB derivatives by gas chromatography was superior to TFA and DNP derivatives. DNP derivatives showed the longest retention time among the given derivatives. Recovery from crops by gas chromatographic met hod ranged 74 to 94%, 78 to 93%, and 85 to 99% in brown rice, rice straw and apple, respectively. Limit of detection was 0.01 ppm for TFA, 0.005 ppm for PFB and 0.02 ppm for DNP derivatives in 50 g of the crop samples.

• Journal of Ginseng Research
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• v.13 no.2
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• pp.178-182
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• 1989

Red ginseng products manufactured by the Korea Ginseng and Tobacco Corporation were analyzed to determine the crude saponin , total saponin and ginsenoside contentents by gravimetry, spertrometry and HPLC, respectively, to see if effective quality control of the components in the products can be achieved. Medicinal powders, powders, tablets and capsules which were made from ginseng powder showed similarity in saponin content, the ratio of PD to PT saponin, and the ginsenoside content and composition, while extract powder, extract, extract tea, extract pills and tea, which were made of ginseng extract, showed difference in saponin content, ratio of PD to PT saponin, and the content and composition of ginsengside. It is, accordingly, believed that ginseng products which are uniform in contents and saponin composition can be produced by carrying out strict quality control throughout the processes of making raw red ginseng into final products.