• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.403-404
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• 2009

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3659-3664
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• 2013

Eight representative explosives (ammonium perchlorate (AP), ammonium nitrate (AN), trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), cyclonite (RDX), cyclotetramethylenetetranitramine (HMX), pentaerythritol tetranitrate (PETN), and hexanitrostilbene (HNS)) were comprehensively analyzed with an ion trap mass spectrometer in negative ion mode using direct infusion electrospray ionization. MS/MS experiments were performed to generate fragment ions from the major parent ion of each explosive. Explosives in salt forms such as AP or AN provided cluster parent ions with their own anions. Explosives with an aromatic ring were observed as either $[M-H]^-$ for TNT and DNT or $[M]^{{\cdot}-}$ for HNS, while explosives without an aromatic ring such as RDX, HMX, and PETN were detected as an adduct ion with a formate anion, i.e., $[M+HCOO]^-$. These findings provide a guideline for the rapid and accurate detection of explosives once portable MS instruments become more readily available.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.417-420
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• 2012

This study is about reduction reaction making 2, 4-dinitrotoluene (2, 4-DNT) to 2, 4-toluene diisocyanate (2,4-TDI) with Pd/$SiO_2$. Catalytic systems based on Pd/$SiO_2$ at about $200^{\circ}C$ and under 100 bars of carbon monoxide. We studied the effect of pyridine on the yield of the TDI. TDI was not created without pyridine, but created with pyridine, at the reaction result. According to research, homogeneous synthesis of TDI with direct carbonylation, palladium and pyridine complexion is known to catalyze. When adding pyridine the reason of TDI synthesis is palladium leaching, ICP-AES was performed to confirm it. As a result, the proportion of Pd loaded in $SiO_2$ was decreased 52% than before, after the reaction by adding 20 vol% pyridine. Generating TDI by adding pyridine might be the effect of the complex ion, which is composed of leached palladium and pyridine.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1698-1699
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• 2011

본 연구는 압전 마이크로캔틸레버 및 생체물질 리셉터를 이용한 인공 후각 장치에 대한 연구이다. 기존의 인공 후각 장치는 폴리머 리셉터를 이용하여 선택적인 감별이 어려웠으나, 본 연구에서 적용된 펩타이드 바이오폴리머 리셉터의 적용을 통해 DNT가스에만 선택적으로 결합하는 후각센서의 개발이 가능하였으며, 이를 통해 인공후각 시스템의 응용가능성에 대해 논하고자 한다.

• Journal of Soil and Groundwater Environment
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• v.17 no.1
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• pp.42-46
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• 2012

The ISO document of ISO/TC/190/SC3/WG11/N11 is a working draft of international standard (WD) dealing with analytical method for the determination of explosives and related compounds using high performance liquid chromatography. The scope of this WD covers the storage of samples, preparing test portion, extraction and instrumentation. The main purpose of this study was to improve the extraction conditions which were already adopted in the WD. For this purpose, mechanical shaking method could be corresponded up to 18 hours of ultrasonic bath extraction in the WD was tested. Methanol was also tested with the intention of being added as an extracting solvent other than acetonitrile in the WD. According to the results, 16 hours of mechanical shaking method showed statistically the same effectiveness as that of 18 hours of ultrasonic bath extraction. In case of extracting solvent, methanol also showed statistically the same extraction capability as acetonitrile for DNB, TNT, 2-A-DNT and 2,4-DNT. However, the recovery rate of TNB with methanol extraction was 40% higher than that of acetonitrile extraction. Through adding mechanical shaking method into committee draft (cf. the next stage draft of the WD during the process for making international standard), ISO standard of analyzing explosives and related compounds in soil would become more useful in dealing with huge number of field samples in the laboratory. In other aspect, adopting methanol as an alternative extracting solvent would be very effective in the terms of exchangeability with GC-ECD/MS method which is being developed by German experts.

• Journal of electromagnetic engineering and science
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• v.3 no.2
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• pp.91-98
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• 2003

Software Communication Architecture(SCA) has been made to reduce the development period of new waveform applications by reusing design modules. Software Defined Radio(SDR) forum adopted SCA specification and follows its design concept. However, SCA specification does not describe interfaces and deployments of resources in details, which are software components, and how to implement them as well as how to communicate each other are another missing points in specification. In this paper, we propose a resource design methodology and details of adapter implementation for Core Framework(CF) that is a core set of open interface and services providing an abstraction of the underlying software and hardware layer. We also present SDR prototype system which communicates with resources implemented in different programming languages and processors in legacy environment through our design methodology.

• Journal of Integrative Natural Science
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• v.2 no.1
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• pp.37-40
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• 2009

Synthesis and characterization of alkyl-capped nanocrystalline silicon (R-n-Si) have been achieved from the reaction of silicontetrachloride with magnesiumsilicide. Surface of silicon nanocrystal has been derivatized with various alkyl groups (R=methyl, n-butyl, etc.). Silicon nanoparticles have been also obtained by the sonication of luminescent porous silicon. Former exhibits an emission band at 360 nm, but latter exhibits an emission band at 680 nm. In this study very sensitive detection of TNT (2,4,6-trinitrotoluene), DNT (2,4-dinitrotoluene), NB (nitrobenzene), and PA (picric acid) has been achieved in gas phase with porous silicon using photoluminescence quenching of the silicon crystallites as a transduction mode. Porous silicon are electrochemically etched from crystalline silicon wafers in an aqueous solution of hydrofluoric acid. We have characterized these silicon nanoparticles by Luminescence Spectrometer (LS 55).

• Textile Coloration and Finishing
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• v.26 no.4
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• pp.277-282
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• 2014

Two tert-butyl substituted phthalocyanines(Pcs), in metal-free and metallated forms, were synthesized and the fluorescence responses toward various nitro derivatives, including picric acid(PA), 2,4-dinitrotoluene(DNT), 1,4-dinitrobenzene(DNB), 4-nitrotoluene(NT), nitrobenzene(NB), 1,4-benzoquinone(BQ), and nitromethane(NM) were investigated. Among the various nitro derivatives, current Pc derivatives exhibited efficient and exclusive fluorescence quenching in the presence of picric acid, which was readily observed by a naked eye. Quenching efficiency was estimated by the Stern-Volmer relationship, in which quenching constant, KSV, was calculated to be in the range of $10^4M^{-1}$. It was also found out that the aggregational behaviors of these Pcs are heavily dependent on the nature of solvent systems, subsequently affecting the quenching efficiency.

• Journal of Integrative Natural Science
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• v.3 no.1
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• pp.19-23
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• 2010

A simple and rapid method is described for detecting nitroaromatic explosives in air or seawater with the use of photoluminescent organosilicon compounds. The synthesis, spectroscopic characterization, and fluorescence quenching efficiency of silafluorenes are reported. Silafluorenes were synthesized from the reduction of dilithiobiphenyl with dichlorosilanes. Two silafluorenes were used for the detection of nitroaromatic compounds. Detection of nitroaromatic molecules, such as 2,4-dinitrotoluene (DNT), 2,4,6-trinitrotoluene (TNT), and picric acid (PA), has been explored. A linear Stern-Volmer relationship was observed for the first three analytes. Fluorescence spectra of silafluorenes obtained in either toluene solutions or thin films displayed no shift in the maximum of the emission wavelength. The photoluminescence quenching occurs by a static mechanism.

• 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.