• Title/Summary/Keyword: Chemical imaging

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Evaluation of Fabric Pilling Using Hybrid Imaging Methods

  • Kim Sung-Min;Park Chang-Kyu
    • Fibers and Polymers
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    • v.7 no.1
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    • pp.57-61
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    • 2006
  • A study has been made on the quantification and evaluation of fabric pilling using two-dimensional and three-dimensional hybrid imaging methods. Two-dimensional imaging method was good for some samples while three-dimensional measurement method for others, according to the properties of their base fabric. Various image processing techniques as well as three-dimensional data processing algorithms were applied for the extraction of pills from measured data and a series of shape parameters have been defined for the objective evaluation of fabric pilling. An evaluation criterion that is compatible with the conventional evaluation method has been proposed by applying the new evaluation method to the current photographic standards.

$^{19}F$ MR Imaging of 5-FU Metabolism in Mice

  • Chaejoon Cheong;Lee, Seung-C.;Jae-G. Seo;Kim, Sung W.;Lee, Chulhyun;Kim, Chul S.;Taegyun Yang
    • Journal of the Korean Magnetic Resonance Society
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    • v.5 no.2
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    • pp.110-117
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    • 2001
  • $^{19}$ F imaging of mice was carried out. For $^{19}$ F imaging, 5-flouro-uracil (5-FU) was injected into a mouse and in vivo detection of the catabolism of 5-FU to a-fluoro-P-alanine (FBAL) was carried out. The chemical shift selective (CHESS) imaging technique was employed. The 19F spectra and images give temporal and spatial information of the metabolism for 5-FU in mice.

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A Study on the 300MHz NMR Transceiver (300MHz급 NMR Transceiver 설계 및 제작)

  • Park, Yang-Ha;Jin, Seung-Oh;Won, Jin-Im;Huh, Young
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.3210-3212
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    • 2000
  • We designed and manufactured 300MHz NMR RF Transceiver. NMR system is composed of NMR Spectrometer, Superconductive Magnet and Pulse Programmer, GUI. NMR RF Transceiver is composed of transmitter, receiver, frequency synthesizer. T/R switch, main power amp., RF coil. To phase modulation, transmitter is composed of mixer, splitter and combiner et al. To weak signal detection, receiver is composed of pre-amp., filter, mixer et al. Each module is manufactured PCB. And installed NMR system to detect chemical component of specimen. In result, we can get the information of specimen.

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Halide Perovskites for X-ray Detection: The Future of Diagnostic Imaging

  • Nam Joong Jeon;Jung Min Cho;Jung-Keun Lee
    • Progress in Medical Physics
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    • v.33 no.2
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    • pp.11-24
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    • 2022
  • X-ray detection has widely been applied in medical diagnostics, security screening, nondestructive testing in the industry, etc. Medical X-ray imaging procedures require digital flat detectors operating with low doses to reduce radiation health risks. Recently, metal halide perovskites (MHPs) have shown great potential in high-performance X-ray detection because of their attractive properties, such as strong X-ray absorption, high mobility-lifetime product, tunable bandgap, low-temperature fabrication, near-unity photoluminescence quantum yields, and fast photoresponse. In this paper, we review and introduce the development status of new perovskite X-ray detectors and imaging, which have emerged as a new promising high-sensitivity X-ray detection technology. We discuss the latest progress and future perspective of MHP-based X-ray detection in medical imaging. Finally, we compare the conventional detection methods with quantum-enhanced detection, pointing out the challenges and perspectives for future research directions toward perovskite-based X-ray applications.

Fabrication of Multicomponent Protein Microarrays with Microfluidic Devices of Poly(dimethylsiloxane)

  • Jeon, Se-Hoon;Kim, Ui-Seong;Jeon, Won-Jin;Shin, Chee-Burm;Hong, Su-Rin;Choi, In-Hee;Lee, Su-Seung;Yi, Jong-Heop
    • Macromolecular Research
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    • v.17 no.3
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    • pp.192-196
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    • 2009
  • Recently, the multi-screening of target materials has been made possible by the development of the surface plasmon resonance (SPR) imaging method. To adapt this method to biochemical analysis, the multi-patterning technology of protein microarrays is required. Among the different methods of fabricating protein microarrays, the microfluidic platform was selected due to its various advantages over other techniques. Microfluidic devices were designed and fabricated with polydimethylsiloxane (PDMS) by the replica molding method. These devices were designed to operate using only capillary force, without the need for additional flow control equipment. With these devices, multiple protein-patterned sensor surfaces were made, to support the two-dimensional detection of various protein-protein interactions with SPR. The fabrication technique of protein microarrays can be applied not only to SPR imaging, but also to other biochemical analyses.

Nanoplasmonic Spectroscopic Imaging and Molecular Probes

  • Choe, Yeon-Ho
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.85-85
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    • 2013
  • Label-free, sensitive and selective detection methods with high spatial resolution are critically required for future applications in chemical sensor, biological sensor, and nanospectroscopic imaging. Here I describe the development of Plasmon Resonance Energy Transfer (PRET)-based molecular imaging in living cells as the first demonstration of intracellular imaging with PRET-based nanospectroscopy. In-vivo PRET imaging relied on the overlap between plasmon resonance frequency of gold nanoplasmonic probe (GNP) and absorption peak frequencies of conjugated molecules, which leads to create 'quantized quenching dips' in Rayleigh scattering spectrum of GNP. The position of these dips exactly matched with the absorption peaks of target molecules. As another innovative application of PRET, I present a highly selective and sensitive detection of metal ions by creating conjugated metal-ligand complexes on a single GNP. In addition to conferring high spatial resolution due to the small size of the metal ion probes (50 nm in diameter), this method is 100 to 1,000 folds more sensitive than organic reporter-based methods. Moreover, this technique achieves high selectivity due to the selective formation of Cu2+complexes and selective resonant quenching of GNP by the conjugated complexes. Since many metal ion ligand complexes generate new absorption peak due to the d-d transition in the metal ligand complex when a specific metal ion is inserted into the complex, we can match with the scattering frequency of nanoplasmonic metal ligand systems and the new absorption peak.

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High-Contrast Imaging of Biomolecular Interactions Using Liquid Crystals Supported on Roller Printed Protein Surfaces

  • Park, Min-Kyung;Jang, Chang-Hyun
    • Bulletin of the Korean Chemical Society
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    • v.33 no.10
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    • pp.3269-3273
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    • 2012
  • In this study, we report a new method for the high contrast imaging of biomolecular interactions at roller printed protein surfaces using thermotropic liquid crystals (LCs). Avidin was roller printed and covalently immobilized onto the obliquely deposited gold surface that was decorated with carboxylic acid-terminated self-assembled monolayers (SAMs). The optical response of LCs on the roller printed film of avidin contrasted sharply with that on the obliquely deposited gold surface. The binding of biotin-peroxidase to the roller printed avidin was then investigated on the obliquely deposited gold substrate. LCs exhibited a non-uniform and random orientation on the roller printed area decorated with the complex of avidin and biotin-peroxidase, while LCs displayed a uniform and planar orientation on the area without roller printed proteins. The orientational transition of LCs from uniform to non-uniform state was triggered by the erasion of nanometer-scale topographies on the roller printed surface after the binding of biotin-peroxidase to the surface-immobilized avidin. The specific binding events of protein-receptor interactions were also confirmed by atomic force microscopy and ellipsometry. These results demonstrate that the roller printing of proteins on obliquely deposited gold substrates could provide a high contrast signal for imaging biomolecular interactions using LC-based sensors.

Critical Enhancement of Photothermal Effect by Integrated Nanocomposites of Gold Nanorods and Iron Oxide on Graphene Oxide

  • Yun, Kum-Hee;Seo, Sun-Hwa;Kim, Bo-Mi;Joe, Ara;Han, Hyo-Won;Kim, Jong-Young;Jang, Eue-Soon
    • Bulletin of the Korean Chemical Society
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    • v.34 no.9
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    • pp.2795-2799
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    • 2013
  • Irradiation of gold nanorods (GNRs) with laser light corresponding to the longitudinal surface plasmon oscillation results in rapid conversion of electromagnetic energy into heat, a phenomenon commonly known as the photothermal effect of GNRs. Herein, we propose a facile strategy for increasing the photothermal conversion efficiency of GNRs by integration to form graphene oxide (GO) nanocomposites. Moreover, conjugation of iron oxide (IO) with the GO-GNR nanohybrid allowed magnetic enrichment at a specific target site and the separated GO-IO-GNR assembly was rapidly heated by laser irradiation. The present GO-IO-GNR nanocomposites hold great promise for application in various biomedical fields, including surface enhanced Raman spectroscopy imaging, photoacoustic tomography imaging, magnetic resonance imaging, and photothermal cancer therapy.

Improvement in Plume Dispersion Formulas for Stack Emissions Using Ground-based Imaging-DOAS Data

  • Lee, Hanlim;Ryu, Jaeyong;Jeong, Ukkyo;Noh, Youngmin;Shin, Sung Kyun;Hong, Hyunkee;Kwon, Soonchul
    • Bulletin of the Korean Chemical Society
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    • v.35 no.12
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    • pp.3427-3432
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    • 2014
  • This study introduces a new method of combining Imaging Differential Optical Absorption Spectroscopy (Imaging-DOAS) data and plume dispersion formulas for power plant emissions to determine the three-dimensional structure of a dispersing pollution plume and the spatial distributions of trace gas volume mixing ratios (VMRs) under conditions of negligible water droplet and aerosol effects on radiative transfer within the plume. This novel remote-sensing method, applied to a power plant stack plume, was used to calculate the two-dimensional distributions of sulfur dioxide ($SO_2$) and nitrogen dioxide ($NO_2$) VMRs in stack emissions for the first time. High $SO_2$ VMRs were observed only near the emission source, whereas high $NO_2$ VMRs were observed at locations several hundreds of meters away from the initial emission. The results of this study demonstrate the capability of this new method as a tool for estimating plume dimensions and trace gas VMRs in power plant emissions.

Synthesis and Biodistribution of Cat's Eye-shaped [57Co]CoO@SiO2 Nanoshell Aqueous Colloids for Single Photon Emission Computed Tomography (SPECT) Imaging Agent

  • Kwon, Minjae;Park, Jeong Hoon;Jang, Beom-Su;Jung, Hyun
    • Bulletin of the Korean Chemical Society
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    • v.35 no.8
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    • pp.2367-2370
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    • 2014
  • "Cat's eye"-shaped $[^{57}Co]CoO@SiO_2$ core-shell nanostructure was prepared by the reverse microemulsion method combined with radioisotope technique to investigate a potential imaging agent for a single photon emission computed tomography (SPECT) in nuclear medicine. The core cobalt oxide nanorods were obtained by thermal decomposition of $Co-(oleate)_2$ precursor from radio isotope Co-57 containing cobalt chloride and sodium oleate. The $SiO_2$ coating on the surface of the core cobalt oxide nanorods was produced by hydrolysis and a condensation reaction of tetraethylorthosilicate (TEOS) in the water phase of the reverse microemulsion system. In vivo test, micro SPECT image was acquired with nude mice after 30 min of intravenous injection of $[^{57}Co]CoO@SiO_2$ core-shell nanostructure.