• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.897-902
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• 2001

The protein back-extraction processes were discussed from the viewpoint of the micelle-micelle interaction. Bovine serum albumin (BSA) suppressing the cluster formation of reverse micelle (positive value of ${\beta}pr)$ has the high back-extra cted fraction (Eb), but cytochrome c enhancing the formation of reverse micelle (negative value of ${\beta}pr)$ has the low back-extracted fraction, relatively. We have also examined quantitatively the effects of alcohol addition and protein solubilization on the percolation process of reverse micelle. The alcohols suppressing the formation of micellar cluster (high values of ${\beta}t)$, remarkably improved the back-extraction rates of BSA and cytochrome c. The values of ${\beta}t$, defined by the variation of percolation process, and the back-extraction behavior of proteins have a good linear correlation. These results indicate that the micelle-micelle interaction or micellar clustering plays an important role in the back-extraction process of proteins.

• Bulletin of the Korean Chemical Society
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• 제25권6호
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• pp.873-877
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• 2004

The relationship between the behaviors of c.c.lipase back-extraction and their percolation phenomena by using AOT reverse micellar systems (RVMS) has been studied by the addition of a small amount of additives to organic phase such as thiols and nonionic-surfactants focusing on micelle-micelle interactions. The values of ${\beta}_t$ defined by the variation of percolation processes and back-extraction behaviors of c.c.lipase have a good linear correlation. The hydrophobicity of additive molecules suppressing the cluster formation of reverse micelles (high values of ${\beta}_t$) improved the back-extraction behavior of c.c.lipase. The back-extraction fraction and its rate of c.c.clipase are increased with decreasing of the value of hydrophilic lipophilic balance (HLB) and increasing of the hydrophobicity per additive molecules added to reverse micellar systems (RVSM) in the same additives concentration.

• 분석과학
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• 제8권4호
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• pp.1089-1094
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• 1995

Methods for the measurement of copper(II) complexing capacity (CuCC) of natural waters by using the back-extraction of bis(benzoyl-trifluoroacetonate)copper(II) and the extraction rate of dithizonato-copper(II) complex were described. Experimental results show that the CuCC of the Kiryu river water samples from urban area were consistently larger than those from up-stream, due to a ligand which originated from human activities.

• KSBB Journal
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• 제15권6호
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• pp.649-657
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• 2000

주입법을 이용하여 AOT 역미셀 용액에 가용화된 BSA를 과잉 수용액으로 역추출할 때 효율에 영향을 미치는 요인들 에 대하여 조사하였다. 특히 수용액의 pH, 수용액에 가한 염 의 종류와 농도, 알코올의 종류에 따른 영향을 검토하였다. 더하여, 역추출된 BSA의 CD 스펙트럼을 원래의 BSA의 CD 스펙트럼과 비교하여 추출공정 중에 발생하는 구조적 변화를 결정하였다. KCI이나 NaCI과 같은 1: 1염을 수용액에 첨가하 면 BSA의 등전점 이상의 pH에서는 거의 100% 역추출 효율을 보였다. 이것은 첨가된 염에 의하여 유발되는 역미셀과 단백질 간의 전기적 상호작용의 변화에 기인한 것으로 추측 된다 $CaCl_2$ 과 $MgCl_2$, 와 같은 1:2염의 경우에는 20% 이하의 역추출 효율을 보였다. 1가 염과 2가 염의 경우 각각 pH=7 과 pH=8에서 최고의 효율을 보였다 표면활성시약으로써 알 코올을 침가하는 경우에는 역추출 효율이 향상됨을 보였다. 과잉 수용액으로 추출된 BSA의 CD 스펙트럼으로부터 추출 공정 중에는 특이할 만한 구조적 변성은 관찰되지 않았으며, 특정된 추출조건에서는 원래의 단백질 보다 높은 활성을 보이기도 하였다.

• 한국산업보건학회지
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• 제9권2호
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• pp.100-109
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• 1999

This study evaluates the pretreatment for analysis of benzidine metabolites in urine by measuring the recovery rates according to the temperature and periods of storage of the urine. By the solid phas e extraction, the recovery rates of basic hydrolysis are benzidine 67.4 %, monoacetylbenzidine 105.1 %, and diacetylbenzidine 115.8 %, respectively. By the liquid extraction, the recovery rates of back-extraction into 0.1 M perchloric acid are benzidine 105.7%, monoacetylbenzidine 94.2 %, diacetylbenzidine 72.8 %, respectively. The difference of the recovery rates between the back-extraction into 0.1 M HCl and 0.1 M perchloic acid after basic hydrolysis are 101 % and 98.8 %, respectively. When the recovery rates of the urinary s amples of pH 3, pH 7, pH 12 at $25^{\circ}C$ and $-76^{\circ}C$ are compared for four weeks, there are no differences according to the temperature and the periods of storage. The above results show that the solid phase extraction and back-extraction by 0.1 M perchloric acid after basic hydrolys is are suitable for the analysis of benzidine metabolites. There are no difference of the recovery rates of the urinary samples stored at $25^{\circ}C$ and $-76^{\circ}C$ at pH 3, pH 7, pH 12, respectively for 28 days.

• 생물환경조절학회지
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• 제1권1호
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• pp.37-51
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• 1992

Quantizing and extracting visual features of mushroom(Lentinus edodes L.) are crucial to the sorting and grading automation, the growth state measurement, and the dried performance indexing. A computer image processing system was utilized for the extraction and measurement of visual features of front and back sides of the mushroom. The image processing system is composed of the IBM PC compatible 386DK, ITEX PCVISION Plus frame grabber, B/W CCD camera, VGA color graphic monitor, and image output RGB monitor. In this paper, an automatic thresholding algorithm was developed to yield the segmented binary image representing skin states of the front and back sides. An eight directional Freeman's chain coding was modified to solve the edge disconnectivity by gradually expanding the mask size of 3$\times$3 to 9$\times$9. A real scaled geometric quantity of the object was directly extracted from the 8-directional chain element. The external shape of the mushroom was analyzed and converted to the quantitative feature patterns. Efficient algorithms for the extraction of the selected feature patterns and the recognition of the front and back side were developed. The developed algorithms were coded in a menu driven way using MS_C language Ver.6.0, PC VISION PLUS library fuctions, and VGA graphic functions.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.90.1-90
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• 2002

Counters for the various kinds of bank notes require high-speed distinctive point extraction and recognition for notes. In this paper we propose a new point extraction and recognition algorithm for bank notes. For distinctive point extraction we use a coordinate data extraction method from specific parts of a bank note representing the same color. The recognition algorithm uses a back-propagation neural network that has coordinate data input. The proposed algorithm is designed to minimize recognition time.

• 한국환경보건학회지
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• 제21권3호
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• pp.96-101
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• 1995

A selective and highly sensitive spectrophotometric measurements have been developed for the determination of trace mercury(II) with thiosulfate and PAR. Hg(II)-thiosulfate complex was extracted into high molecular alkylamine such as quaternary ammonium salt and back extracted into 1 M-HCl solution. The Hg(II)-PAR complex has maximum absorbance at 499 nm and obeys Beer's law in the range of 0.04~1.0 $\mu g/mL$ of mercury(II). The molar absorptivity and Sandell's sensitivity are $6.27\times 10^4 L.mole^{-1} cm^{-1}$ and $3.2\times 10^{-3}g/cm^2$ respectively.

• 제어로봇시스템학회논문지
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• 제6권6호
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• pp.486-491
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• 2000

The dicing process cuts a semiconductor wafer to lengthwise and crosswise direction by using a rotating circular diamond blade. But inferior goods are made under the influence of several parameters in dicing such as blade, wafer, cutting water and cutting conditions. This paper describes a monitoring algorithm using neural network in order to find out an instant of vibration signal change when bad dicing appears. The algorithm is composed of two steps: feature extraction and decision. In the feature extraction, five features processed from vibration signal which is acquired by accelerometer attached on blade head are proposed. In the decision, back-propagation neural network is adopted to classify the dicing process into normal and abnormal dicing, and normal and damaged blade. Experiments have been performed for GaAs semiconductor wafer in the case of normal/abnormal dicing and normal/damaged blade. Based upon observation of the experimental results, the proposed scheme shown has a good accuracy of classification performance by which the inferior goods decreased from 35.2% to 6.5%.

• KSBB Journal
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• 제14권6호
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• pp.661-664
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• 1999

Lysozyme 수용액으로부터 역미셀을 이용한 Lysozyme 추출공정에서 주요변수인 pH, 이온강도, AOT 농도, 추출시간 등을 실험을 통하여 연구하였으며, 미셀내의 수분함량과 lysozyme 농도는 비례관계임을 KCl 농도변화에 따른 결과로서 알 수 있었다. 본 연구에 사용된 lysozyme의 등전점이 약 11.2로 음이온 계면활성제를 사용할 경우 추출공정에 유리함을 알 수 있었고, 추출공정(forward extraction)에서의 최적조건은 pH 6-9일 때, 그리고 0.1 M 염농도와 50 mM이하의 AOT 농도에서 가장 높은 lysozyme 추출 효율을 얻을 수 있었다. 그리고 역추출(back extraction)에서는 pH 12이상, 1M 염농도에서 Lysozyme의 가장 높은 추출 효율을 나타내었다.