• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.51-54
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• 2003

Three kinds of experiments were conducted to test existing methods and develop an effective methodology for the remediation of DNAPL trapped in vertical dead-end fractures. A water-flushing method failed to remove TCE from vertical dead-end fractures where no fluid flow occurs. A water-flushing experiment implies that existing remediation methods, utilizing water-based remedial fluid such as surfactant-enhanced method, have difficulty in removing DNAPL trapped from the vertical downward dead-end fractures, because of no water flow through dead-end fractures, capillary, and gravity forces. Fluid denser than TCE was injected into the fracture network, but did not displace TCE from the vertical dead-end fractures. Base(B on the analysis of the experiments, the increase in the density of the dense fluid and the addition of surfactant to the dense fluid were suggested, and this composite dense fluid with surfactant effectively removed TCE from the vertical dead-end fractures.

• Proceedings of the KIEE Conference
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• 2007.04b
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• pp.131-133
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• 2007

This paper was described about the calibration method and setup of calibration system. This method and system were based on ISO 12713 and 12714. This system consisted of a conical type reference sensor, test block, glass capillary source and measuring oscilloscope. The waves of reference sensor and tested sensor was shown and these wave was analyzed with ISO method.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.2
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• pp.107-111
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• 2007

A two-dimensional numerical method for inviscid two-fluid flows with evolution of density interface is developed, and an initially stationary two-dimensional fluid sheet surrounded by another fluid is studied. The interface between two fluids is modeled as a vortex sheet, and the flow field with the evolution of interface is solved by using vortex-in-cell/front-tracking method. The edge of the sheet is pulled back into the sheet due to surface tension and a blob is formed at the edge. This blob and fluid sheet are connected by a thin neck. In the inviscid limit, such process of the blob and neck formation is examined in detail and their kinematic characteristics are summarized with dimensionless parameters. The edge recedes at and the capillary wave propagating into the fluid sheet must be considered for better understanding of the edge receding.

• Applied Chemistry for Engineering
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• v.7 no.1
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• pp.59-66
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• 1996

Novel chitosan beads containing a series of bisamino-terminated polyethylene glycol (Bisamino-PEG, $Jeffamine^{(R)}ED$ series) have been prepared via capillary extrusion method using an alkaline solution. The results of swelling kinetics of chitosan beads showed that as the chain length of PEG in chitosan beads increased, the swelling process of the beads proceeded slowly. In order to study the releasing kinetics quantitatively, fluorescamine was coupled to the pendant amino groups and the releasing processes were followed by UV spectra. The results revealed that the releasing process was retarded in the order of $Jeffamine^{(R)}ED$-600 < $Jeffamine^{(R)}ED$-900 < $Jeffamine^{(R)}ED$-2001 as the chain length of PEG was increased. The slow release of PEG from the beads is considered to be governed by the chain length of PEG and interpolymeric hydrogen bonding between PEG and the chitosan molecule.

• Biomedical Science Letters
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• v.2 no.2
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• pp.249-255
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• 1996

In this paper, a in situ hybridization(ISH) has been used to investigate the yield of viral RNA expression from each organ tissues. It is studied to establish a rapidly, specific diagnostic method detecting rabbit haemorrhagic disease virus(RHDV) RNA in 10% formalin-fixed, paraffin-em-bedded tissues of naturally RHDV-infected rabbits using oligonucleotide probe to be made by RHDV total sequences. Biotin was used as the oligonucleotide probe marker. in situ hybridization is detected the virus genome in the cells and tissue as specifically compared with others nucleic acid hybridization method. All ISH procedure of RHDV were completed to Mi-croProbe$^{TM}$ capillary action system within 1-2 hours. In this report, RHDV was distributed widely in the cytoplasm of liver cell and the cortex of kidney but lung tissue and medulla of kidney were showed to positive reaction at locally. Although not entirely free of technical limitations, nucleic acid identification holds advantages over other diagnostic tests, including exquisite sensitivity, specificity, interchangeability and speed. It is expected that, in the immediate future viral nucleic acid detection will be a prominent part of the methods used in histopathology.

• Journal of the Korean Society of Tobacco Science
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• v.29 no.2
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• pp.125-131
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• 2007

Hydrogen cyanide(HCN), formed from pyrolysis of various nitrogenous compounds such as protein, amino acids and nitrate in tobacco, is present in both the particulate phase and vapor phase of cigarette smoke. Typically the determination of HCN in cigarette smoke has been done through colorimetric and electrochemical techniques, such as fluorescence spectrometry, UV-spectrophotometry (UV), continuous flow analyzer (CFA), capillary GC-ECD and ion chromatography (IC). Most of these techniques are known to be time-consuming and some of them lack specificity or sensitivity. The available results from both our laboratory and reported literatures for 2R4F Kentucky reference cigarette, smoked under ISO condition, show a relatively wide variation ranging from 100 to 120 ug/cig of HCN. Especially, the precision and accuracy of the analytical results of HCN tend to get worse in low tar cigarettes and under intense smoking condition. In this paper, a more optimized analytical methods than previous ones are suggested. This method shows lower detection limit and has improved precision and accuracy, so it is applicable for wide tar level cigarettes under intense smoking condition as well as under ISO smoking condition. Important features of this method are improved sample collection and quantification systems such as the number of trapping units, volume, temperature and type of trapping solution. To avoid volatilization loss of HCN in analyzing mainstream smoke, it is highly recommended that pH values of trapping solutions should be maintained over 11 and cold traps should be used in collecting mainstream smoke.

• Analytical Science and Technology
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• v.5 no.2
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• pp.159-167
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• 1992

An improved and accurate method for the determination of linear alkybenzene sulfonate(LAS) in river water is described by using gas chromatography and GC/MS. The gas chromatograph equipped with BP-5 capillary column was satisfactory for isolation of the homologues and isomers of LAS in river water. Four LAS homologues, $C_{10}$, $C_{11}$, $C_{12}$, $C_{13}$ alkyl chains were determined in Jungrang stream, Jinwi stream and down stream of Han river tributary. Especially $5-C_{11}$, $6-C_{11}$, $2-C_{12}$ and $6-C_{13}$, $7-C_{13}$ of LAS were identified by mass chromatogram. Different composition of LAS in standard and river water expressed the distribution and fate of LAS in river water. The remarkable reduced content of $C_{12}$ and $C_{13}$ in river water implied that the biodegradation of LAS more easily occured in longer alkylchain one. This method would be applicable for determination of LAS in water with high resolution and sensitivity.

• Food Science of Animal Resources
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• v.32 no.2
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• pp.241-246
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• 2012

This report outlines the development of a rapid, simple, and sensitive detection system for pathogenic bacteria using a capillary electrophoresis-based, single strand conformation polymorphism (CE-SSCP) combined with PCR. We demonstrate that this method, used with primers targeting the V4 region of the16S rRNA gene, is capable of the simultaneous detection of 10 microbes that could be associated with foodborne illness, caused by animal-derived foods: Salmonella enterica, Listeria monocytogenes, Escherichia coli O157:H7, Campylobacter jejuni, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Yersinia enterocolitica, Vibrio parahaemolyticus, and Enterobacter sakazakii. The traditional detection techniques are time-consuming and labor-intensive, due to the necessary task of separate cultivation of each target species. As such, the CE-SSCP-PCR method, that we have developed, has the potential to diagnose pathogens rapidly, unlike the traditional technique, in order to prevent foodborne illness in a much more efficient manner.

• Magazine of the Korea Concrete Institute
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• v.4 no.1
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• pp.89-96
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• 1992

It is generally known that the frost-resistance of concrete is much affected by the air content in concrete and by the air void system or air distribution. And also the frost-resistance is believed to vary with the stre¬ngth of concrete. This article is prepared to describe, based on experiment, the effect of the air content and the air void system, particularly the effect of the spacing factor, on the freeze-thaw resistance of the high strength conc¬rete. For this purpose, I first worked on Non-AE concrete to make its compressive strength set about 400 to 500 kg/em'. However, the freeze-thaw test on the Non-AE concrete resulted in low durability factor, I.e., 10-2~0%. Thus to enhance the durability, another supplementary step was needed. I used AE admixture. which enhanced durability by changing the air content from 2% to 12%. The frost-thaw test was then performed 500 cycles on the 20 kind of concrete mixtures which differ in unit cement content and in water-cement ratio. Keywords : frost -resistance, air content, air void system, air distribution, spacing factor, freeze-thaw test, dur ability factor. capillary cavity, Linear Traverse Method.

• Analytical Science and Technology
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• v.13 no.1
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• pp.101-107
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• 2000

The automotive paints could be generally differentiated by color, layer sequence and chemistry of the paint layers comprising each of the topcoat and the primer system. The successful identification of hit-andrun a and traffic accidental vehicles from evidential paint fiagments is greatly facilitated with a comprehensive laboratory collection of reference paint samples and the technique for direct analysis without sample preparation. The Pyrolysis-Gas Chromatography(PGC) is a precise and reliable method for performing both quantitative and qualitative analysis of polymeric materials and forensic samples. Our Forensic Laboratory is conducting the examination and identification of 73 reference paint samples; 4 colors of each domestic automotive make that is popular in Korea, by Curie Point Pyrolyzer(JHP-3) and GC with capillary column(ultra alloy-5). This method can be used not only to compare paint traces with their suspected sources, but also to identify the type, make and model of the automotive car.