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Determination of Chromium Content in Carbon Steel Pipe of NPP using ICP-AES
Kyuseok Song,Yong Joon Park,Sun-Ho Han,Chang Heon Lee,Kwang-Soon Choi 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.12
A method is proposed for determining chromium content in the carbon steel pipes of a nuclear power plant (NPP) to evaluate wall thinning caused by flow-accelerated corrosion (FAC). A flat file was used to obtain filings samples. To assess sampling quality, a disk form of SRM 1227 was ground with the flat file, and the amount of Cr in the filings was determined by ICP-AES. The content of chromium in the filings of SRM 1227was estimated as six times higher than the certified value due to the contamination of chromium in the file. To eliminate chromium contamination from the file, it was coated with WC-12Co using high-velocity oxygen-fuel (HVOF) spraying systems. After obtaining filings samples using the coated file, Cr content in four types of disk-form SRMs was determined by ICP-AES. The recoveries of Cr in the disk-form SRMs were in the range of 95.4-102.6%, with relative standard deviations from 0.43 to 3.0%. The Cr contents in the filings collected from the used outlet headers of the nuclear power plants using the flat file coated were in the range of 0.11-0.19%
Recent Developments in Nuclear Forensic and Nuclear Safeguards Analysis Using Mass Spectrometry
Song, Kyuseok,Park, Jong-Ho,Lee, Chi-Gyu,Han, Sun-Ho Korean Society for Mass Spectrometry 2016 Mass spectrometry letters Vol.7 No.2
The analysis of nuclear materials and environmental samples is an important issue in nuclear safeguards and nuclear forensics. An analysis technique for safeguard samples has been developed for the detection of undeclared nuclear activities and verification of declared nuclear activities, while nuclear forensics has been developed to trace the origins and intended use of illicitly trafficked nuclear or radioactive materials. In these two analytical techniques, mass spectrometry has played an important role in determining the isotope ratio of various nuclides, contents of trace elements, and production dates. These two techniques typically use similar analytical instruments, but the analytical procedure and the interpretation of analytical results differ depending on the analytical purpose. The isotopic ratio of the samples is considered the most important result in an environmental sample analysis, while age dating and impurity analysis may also be important for nuclear forensics. In this review, important aspects of these techniques are compared and the role of mass spectrometry, along with recent progress in related technologies, are discussed.
Kyuseok Song,Euo Chang Jung,Hyungki Cha,Jeongsik Moon,Sang Chun Lee 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.51 No.I
The characteristic behaviors of the post-ionized signals of neutral atoms generated by either ion beam sputtering or laser ablation were investigated by adopting a Pb plate as a target sample. The signal intensities and the threshold laser power for ion generation were compared for various the ion generation schemes, such as laser ablation with 532 nm laser only (Case I), 2-color resonant laser ablation by using 532 nm and 283.3 nm lasers (Case II), laser ablation with 532 nm laser followed by resonant post-ionization with 283.3 nm laser (case III), and 2-color resonant laser ablation followed by resonant post-ionization (case IV). Case I required the highest threshold laser power required for ion generation while Case III with a 500 ns delay between the two laser pulses, 532nm and 283.3 nm, required the least laser power for the generation of ion signals. A comparison of the ion signal intensities between case II and case IV revealed a variation in the signal intensity that depended on the time delay between the ablation laser pulse and the ionization laser pulse. Meanwhile, the post-ionization of the neutrals generated by ion beam sputtering (case V) showed a comparable ion signal to that of the post-ionization signal of the laser-induced plasma. The resonant post-ionization of the sputtered neutrals showed a more than 10 times signal enhancement with the use of a 100 times less laser power, 0.6 mW, when compared to the case of non-resonant laser ionization with 60 mW at 355 nm. The behavior of the ion signal of the sputtered neutrals was also investigated by varying the experimental parameters, such as the time delay between the ion beam pulse and the laser pulse, the ion beam pulse and the high voltage pulse for ion extraction, and the high voltage applied to the ion extraction.
Song, Suhee,Lee, Joonhee,Kweon, Songa,Song, Jaeeun,Kim, Kyuseok,Kim, Byeong-Su American Chemical Society 2016 Biomacromolecules Vol. No.
<P>Functional hyperbranched polyglycerols (PGs) have recently garnered considerable interest due to their potential in biomedical applications. Here, we present a one-pot synthesis of hyperbranched PGs possessing, amine functionality using a novel amino glycidyl ether monomer. A Boc-protected butanolamine glycidyl ether (BBAG) monomer was designed and polymerized with glycidol (G) through anionic ring-opening multibranching polymerization to yield a series of hyperbranched P(G-co-BBAG) with controlled molecular weights (4800-16700 g/mol) and relatively low molecular weight distributions (1.2-1.6). The copolymerization and subsequent deprotection chemistry allow the incorporation of an adjustable fraction of primary amine moieties (typically, 5-20% monomer ratio) within the hyperbranched PG backbones, thus providing potentials for varying charge densities and functionality in PGs. The copolymerization kinetics of G and BBAG was also evaluated using a quantitative in situ C-13 NMR spectroscopic analysis, which revealed gradient copolymerization between the comonomers. The free amine groups within the deprotected P(G-co-BAG) copolymer were further utilized for a facile conjugation chemistry with a model molecule in a quantitative manner. Furthermore, the superior biocompatibility of the prepared P(G-co-BAG) polymers was demonstrated via cell viability assays, outperforming many existing polyamines possessing relatively high cytotoxicity. Taken together, the biocompatibility with facile conjugation chemistry of free amine groups sheathed within the framework of hyperbranched PGs holds the prospect of advancing biological and biomedical applications.</P>
Isotopic Analysis of a Single Pb Particle by Using a Laser Ablation Time-of-Flight Mass Spectrometry
최인희,Kyuseok Song,유희수 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.56 No.1
Laser ablation with mass spectrometry has been applied for a direct isotopic analysis of particle samples. A single Pb micro particle, which was loaded onto various matrix plates, was analyzed by using laser ablation time-of-flight mass spectrometry. Laser ablation was achieved using a second harmonic of the Nd:YAG laser, with a silicon wafer, a cotton textile, and a Ta metal plate being were used as a sample loading matrix. The slightly defocused condition of the laser beam was identified as being adequate for a particle analysis while the silicon wafer plate was identified as being the most suitable matrix for the analysis of Pb with a reasonable mass resolution. The high thermal conductivity and absorption coefficient of silicon for visible light are regarded as characteristics that may provide a good mass resolution and signal-to-noise ratio when compared with the other matrices adopted in this study. The isotopes of Pb were also analyzed by applying a resonance ionization technique. The results showed that the ion signal was more than 10 times higher than that of the non-resonance condition.