• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.460-464
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• 2013

Single-chain variable fragments of antibodies (scFv) specific to 2,4-dinitrotoluene (DNT) were isolated from a phage library displaying synthetic human scFv fragments with 6 diversified complementary determining regions (CDRs). A DNT derivative that contained an extended amine group was synthesized and conjugated to the NHS-group that was linked to magnetic beads. Phages specific to the immobilized DNT derivatives were isolated from the library after 4 rounds of sequential binding and elution processes. The displayed scFv fragments from the isolated phages showed consensus CDR sequences. One DNT-specific scFv was expressed in E. coli and purified using Ni-affinity chromatography. The purified DNT-specific scFv binds specifically to the immobilized DNT-derivative with $K_D$ value of $6.0{\times}10^{-7}$ M. The scFv and DNT interaction was not disrupted by the addition of 4-nitrotoluene or benzoic acid. These data demonstrate that the screened scFv from the phage displayed library could be used for selective and sensitive detection of explosives such as TNT.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.4
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• pp.510-520
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• 2014

Metal-Organic Frameworks(MOFs) are attracting attentions from various fields including chemistry, materials science, physics and medical science because of its exceptionally large pore volumes and surface areas which far exceed those of zeolites. The possibilities of applications of MOFs for gas separation, catalysts, drug delivery, and high explosives detections have already been verified. In these review the author describes the structures, synthetic methods and applications of MOFs based on the literatures published during last 15 years to give the readers general pictures of MOF itself as well as the global research trends of these materials.

• Journal of Soil and Groundwater Environment
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• v.14 no.1
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• pp.51-60
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• 2009

A series of experiments was performed to develop an optimized analytical procedure for the analysis of explosives in soil by HPLC with soil samples collected at two live-fire military shooting ranges. The minimum amount of soil to be collected, Wmin, for the analysis of explosive compounds was 125g, based on the segregation and homogeneity constants that account for soil heterogeneity and non-homogeneous distribution of target explosive compounds. The optimization of extraction and HPLC analytical conditions were also studied based on analytes CV values. The most effective soil/ extractant ratio was estimated to be 10g-pretreated soil/20 mL acetonitrile as extractant. The optimized HPLC elution conditions for the separation of US EPA designated 14 explosive compounds, were column temperature 30${\circ}C$, eluents ratio of isopropanol: acetonitrile: water = 18 : 12: 70, and flow rate of 0.8 mUmin at 230 nm. However, UV wavelength 254 nm was better for the analysis of NB, 2,4-DNT, 2NT, 4NT, and 3NT.

• Analytical Science and Technology
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• v.10 no.5
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• pp.325-331
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• 1997

Among various CE separation methods, micellar electrokinetic capillary chromatography(MECC) method using sodium dodecylsulfate(SDS) provides rapid and accurate separation of organic explosive constituents with easy. The running buffer was composed with 2.5 mM borate and 25mM SDS(pH 8.5). Addition of 1M urea and 10% organic modifiers (acetonitrile, methanol and ethanol) improves the resolution of adjacent explosive constituents. When 15 explosive constituents were developed in MECC, most constituents were separated successively while RDX/TNB and DNN/DEP were not, and detection limits of separated compounds are in range of 1 to 4 ppm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.12
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• pp.1243-1249
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• 2014

The naval mine is the explosives that are installed in the water in order to attack surface ships or submarines. So mine warfare is a very important component of naval operations. In this paper, first, understanding of the general concept about mine warfare. Second, introduce the mine hunting progress and mine sweeping progress. And then, suggest the system design method of mine counter measure warfare using several functions. The functions are mine area detection algorithm for side scan sonar image using Adaboost algorithm, and calculation to mine hunting progress rate and mine sweeping progress rate. And techniques that lead the mine disposal vehicle(MDV) to mine.

• Analytical Science and Technology
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• v.33 no.2
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• pp.86-97
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• 2020

Reconstruction and separation of explosive-contaminated overlapping fingerprints constitutes an analytical challenge of high significance in forensic sciences. Laser-induced breakdown spectroscopy (LIBS) allows real-time chemical mapping by detecting the light emissions from laser-induced plasma and can offer powerful means of fingerprint classification based on the chemical components of the sample. During recent years LIBS has been studied one of the spectroscopic techniques with larger capability for forensic sciences. However, despite of the great sensitivity, LIBS suffers from a limited detection due to difficulties in reconstruction of overlapping fingerprints. Here, the authors propose a simple, yet effective, method of using chemical mapping to separate and reconstruct the explosive-contaminated, overlapping fingerprints. A Q-switched Nd:YAG laser system (1064 nm), which allows the laser beam diameter and the area of the ablated crater to be controlled, was used to analyze the chemical compositions of eight samples of explosive-contaminated fingerprints (featuring two sample explosive and four individuals) via the LIBS. Then, the chemical validations were further performed by applying the Raman spectroscopy. The results were subjected to principal component and partial least-squares multivariate analyses, and showed the classification of contaminated fingerprints at higher than 91% accuracy. Robustness and sensitivity tests indicate that the novel method used here is effective for separating and reconstructing the overlapping fingerprints with explosive trace.

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3703-3706
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• 2010

Biomolecules specific to explosives can be exploited as chemical sensors. Peptides specific to immobilized dinitrotoluene (DNT) were identified using a phage display library. A derivative of DNT that contained an extended amine group, 4-(2,4-dinitrophenyl)butan-1-amine, was synthesized and immobilized using a self-assembled monolayer surface on gold. Filamentous M13 phages displaying random sequences of 12-mer peptides specific to the immobilized DNT-derivate were isolated from the M13 phage library by biopanning. A common peptide sequence was identified from the isolated phages and the synthesized peptides showed selective binding to DNT. When the peptide was immobilized on a quartz crystal microbalance (QCM) chip, it showed a binding signal to DNT, while toluene barely showed significant binding to the QCM chip. These results demonstrate that peptides screened by biopanning against immobilized DNT can be useful for quick and accurate detection of DNT.

• Analytical Science and Technology
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• v.16 no.5
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• pp.1041-1051
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• 2003

Neutron induced prompt gamma activation analysis (PGAA) offers a nondestructive, sensitive and relatively rapid method for the determination of trace and major elements and is proven to be convenient for online analysis of minerals, metals, coal, cement, petrochemical, coating, paper as well as many other materials and products. The technique has found many uses in medicine, industry, research, security and the detection of contraband items. This report reviews the present status and future trends of the PGAA techniques. Requirements for the system are neutron source, high resolution HPGe detectors with a high-voltage power supply, an amplifier, analog-to-digital converter, and a multichannel analyzer for the detection and measurement of prompt ${\gamma}$-ray emit form the neutron capture elements. Introducing a ${\gamma}$-${\gamma}$ coincidence system also improves the quality of the ${\gamma}$-ray spectrum by suppressing the background created from the Compton scattering of high energy prompt ${\gamma}$-rays. A PGAA system using a $^{252}Cf$ neutron source is currently under construction for the on-line measurement of several elements in aqueous samples at KAERI. The system can be applied for the detection of chemical weapons and explosives as well as various narcotics.

• Journal of electromagnetic engineering and science
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• v.11 no.1
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• pp.42-50
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• 2011

One of the important applications of THz time-domain spectroscopy (TDS) is the detection of explosive materials through identification of vibrational fingerprint spectra. Most recent THz spectroscopic measurements have been made using pellet samples, where disorder effects contribute to line broadening, which results in the merging of individual resonances into relatively broad absorption features. To address this issue, we used the technique of parallel plate waveguide (PPWG) THz-TDS to achieve sensitive characterization of three explosive materials: TNT, RDX, and HMX. The measurement method for PPWG THz-TDS used well-established ultrafast optoelectronic techniques to generate and detect sub-picosecond THz pulses. All materials were characterized as powder layers in 112 ${\mu}m$ gaps in metal PPWG. To illustrate the PPWG THz-TDS method, we described our measurement by comparing the vibrational spectra of the materials, TNT, RDX, and HMX, applied as thin powder layers to a PPWG, or in conventional sample cell form, where all materials were placed in Teflon sample cells. The thin layer mass was estimated to be about 700 ${\mu}g$, whereas the mass in the sample cell was ~100 mg. In a laboratory environment, the absorption coefficient of an explosive material is essentially based on the mass of the material, which is given as: ${\alpha}({\omega})=[ln(I_R({\omega})/I_S({\omega}))]m$. In this paper, we show spectra of 3 different explosives from 0.2 to 2.4 THz measured using the PPWG THz-TDS.

• Journal of Korean Society for Quality Management
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• v.49 no.2
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• pp.113-125
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• 2021

Purpose: This study focused on reality and quality improvement of aviation security equipment performance certification system. Methods: For this propose, we analyzed aviation security equipment performance certification system related legislations. Using analyzed data, we suggested advancement plan of aviation security equipment performance certification system. Results: In results, South Korea has been implementing aviation security performance certification system since October 2018. Parts for improvement of system are mutual certification with major countries that operate aviation security equipment performance certification systems, the spread of the defense industry's system, development of similar substances for handling explosives, and introduction of preliminary inspections. Conclusion: The research result could be used as a basic data for upgrading Korea's aviation security performance certification system.