• Analytical Science and Technology
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• v.24 no.6
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• pp.451-459
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• 2011

Eight coordinated terbium(III) complexes, tris (2-pyrazinecarboxylato)(phenanthroline) terbium(III) [$Tb(pzc)_3$(phen)], tris (5-methyl-2-pyrazinecarboxylato) (phenanthroline) terbium(III) [$Tb(mpzc)_3$(phen)] and tris(2-picolinato) (phenanthroline) terbium(III) [$Tb(pic)_3$(phen)], have been synthesized and characterized by Fourier transform infrared (FT-IR), UV-Visible and X-ray photoelectron spectroscopy. Photoluminescence (PL) spectroscopy shows that these complexes emitted strong green luminescence. When powder samples of the $Tb^{3+}$ complexes are examined using time-resolved spectroscopic analysis, the luminescence lifetimes are found to be 0.87 ms and 1.0 ms, respectively. Thermogravimetric analysis reveals the terbium complexes to have good thermal stability up to $333-379^{\circ}C$. Cyclic voltammetry shows that HOMO-LUMO energy gap of the $Tb^{3+}$ complexes ranges from 4.26~4.41 eV. These values are similar to those obtained from the UV-visible spectra. Overall, the synthesized $Tb^{3+}$ complexes may be useful advanced materials for green light emitting devices.

• Environmental Analysis Health and Toxicology
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• v.29
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• pp.18.1-18.9
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• 2014

Objectives The purpose of this study was to determine a separation method for each arsenic metabolite in urine by using a high performance liquid chromatography (HPLC)-inductively coupled plasma-mass spectrometer (ICP-MS). Methods Separation of the arsenic metabolites was conducted in urine by using a polymeric anion-exchange (Hamilton PRP X-100, $4.6mm{\times}150mm$, $5{\mu}m$) column on Agilent Technologies 1260 Infinity LC system coupled to Agilent Technologies 7700 series ICP/MS equipment using argon as the plasma gas. Results All five important arsenic metabolites in urine were separated within 16 minutes in the order of arsenobetaine, arsenite, dimethylarsinate, monomethylarsonate and arsenate with detection limits ranging from 0.15 to $0.27{\mu}g/L$ ($40{\mu}L$ injection). We used G-EQUAS No. 52, the German external quality assessment scheme and standard reference material 2669, National Institute of Standard and Technology, to validate our analyses. Conclusions The method for separation of arsenic metabolites in urine was established by using HPLC-ICP-MS. This method contributes to the evaluation of arsenic exposure, health effect assessment and other bio-monitoring studies for arsenic exposure in South Korea.

• Journal of radiological science and technology
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• v.32 no.1
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• pp.39-43
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• 2009

The medical diagnostic examination using ionizing radiation has improved the patients' life and brought revolution in medical examination along with the mechanical development. However, the development of medical imaging systems has also been the reason to increase the patients' exposure for ionizing radiation. ICRP recommends that each country adopts diagnostic reference levels depending on regional and national situations. The Korea Food & Drug Administration suggested the dosimetry measurement guideline for patients in 2007. Nonetheless, in reality, it is hard to know the skin dose of the patients when applying a x-ray since there is no radiation dosimeter in most of clinical situation. Therefore, this study sets a program based on the bit system to figure out easily the skin dose of a patients using MS Excel program in the PC setting. The results showed 10% better outcome.

• Korean Journal of Medicinal Crop Science
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• v.20 no.3
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• pp.190-194
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• 2012

Shoot tips of chinese yam (Dioscorea opposita Thunb.) were cultured on MS medium containing 0.5 mg/L BA to produce micro-tubers in vitro. To stimulate the formation of shoots and micro-tubers, and produce large micro-tubers, the sections of micro-tubers were cultured on MS media with BA and IAA. The shoot multiplication, and the micro-tuber formation and growth were very effective on the media containing 2.0 mg/L BA and 0.5~1.0 mg/L IAA. Sucrose added to MS medium with 2.0 mg/L BA and 0.5 mg/L IAA to stimulate more micro-tuber growth. The medium added 50 g/L sucrose was very effective in the increase of plant fresh weight and micro-tuber growth. After 4 weeks' culture of micro-tuber sections on the medium with 2.0 mg/L BA, 0.5 mg/L IAA and 50 g/L sucrose, the liquid media were added into the same vessels. The micro-tuber growth was stimulated remarkably by the addition of liquid medium. The addition of 25 $m{\ell}$ liquid medium containing 10 g/L activated charcoal, 3x MS salts and 250 g/L sucrose was the most effective in micro-tuber growth.

• Horticultural Science & Technology
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• v.35 no.1
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• pp.46-58
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• 2017

This study was conducted to investigate the optimal conditions for spore germination, prothallus propagation, sporophyte formation and seedling growth in Microlepia strigosa (Thunb.) C. Presl. Spore germination and prothallus development were promoted by low concentrations of Knop medium nutrient solution. The optimal medium for prothallus propagation and antheridium formation was 2X MS medium with 3% sucrose. The activated charcoal content of the medium did not affect prothallus proliferation. Among the various combinations of culture soil (bedding soil, peat moss, perlite and decomposed granite), a mixture of bedding soil, peat moss and decomposed granite at a ratio of 1 : 1 : 1 (v : v : v) had a positive effect on sporophyte formation. The most efficient conditions for promoting the growth of whole plants (sporophyte seedlings) were 50 - cell plug trays filled with a mixture of bedding soil and decomposed granite at a 2 : 1 (v : v) ratio.

• Journal of Conservation Science
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• v.36 no.3
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• pp.213-224
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• 2020

This research conducted a component analysis and conservation treatment of "Sangryangmun," a material which had been written in 1965 and was discovered during the repair project for "Jinnamgwan" in Yeosu. The "Sangryangmun" has been stored in a cylindrical metal storage; however, defects, discolorations, hardening, and damages caused by pollutants were found. Based on the XRF analysis, rust in the cylindrical metal storage, which was made of Cu, was stuck on the surface of the "Sangryangmun". Using FT-IR and Pyrolysis-GC/MS analyses, carbonyl and compounds of fatty acids were detected; the organic material on the surface of the "Sangryangmun" was identified to have belonged to oil-based components. Therefore, it was presumed that the bast fibers of a mulberry was used in the paper. To determine the conservation materials, component analysis, condition survey, and preliminary test on adhesives were conducted. Moreover, the missing parts and partial linings were filled using mulberry-fiber paper, methyl cellulose, etc.

• Analytical Science and Technology
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• v.28 no.5
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• pp.309-316
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• 2015

The analytical method of lead in plasma by ICP-MS was validated after securing environment within class 1,000 classification. We tested specificity and accuracy of within-run and between-run. According to measurement of the amount of suspended particulates in a clean room, 0.3~62 particles were detected in 0.3 µm size while 0.0~28.3 particles were observed in 0.5 µm size. Total suspended particulates met required environment with up to 90.3 particles. The MDL (Method detection limit) of the sample which has been fabricated using fetal bovine serum (FBS) blank was 1.77 ng/L, and LOQ (Limit of quantification) was 5.55 ng/L. The slope, intercept and correlation coefficient of the calibration curve were y=1.09×10⁻³x+4.88×10⁻² and r=0.9999, which showed good correlation. The specificity, within-run and between-run accuracy satisfied the standard at more than 50 ng/L. The average lead concentration in plasma of the general people, current workers and retired workers was 55.4 ng/L, 440 ng/L, and 132 ng/L.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.3
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• pp.341-350
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• 1996

The CdS thin films are grown on quartz plate by hot wall epitaxy. The source and substrate temperature is $590^{\circ}C$ and $400^{\circ}C$ respectively, and thickness of the film is $2.5\;\mu\textrm{m}$. Using extrapolation method of X-ray diffraction patterns for the CdS thin film, it was found hexagonal structure whose lattice constant a and c were $4.137\;{\AA}$ and $6.713\;{\AA}$, respectively. Hall effect on this sample was measured by the method of van der Pauw and studied on cattirer density and mobility depending on temperature. From hall data, the mobility was likely to be decreased by piezoelectric scattering in the temperature range 30 K to 200 K and by polar optical scattering in the temperature range 200 K to 293 K. In order to explore the applicability as a photoconductive cell we measured the sensitivity ($\gamma$), the ratio of photocurrent to darkcurrent (pc/dc), maximum allowable power dissipation (MAPD), spectral response and response time. The results indicated that for the samples annealed in Cu vapor the photoconductive characteristics are the best. Then we obtained the sensitivity of 0.99, the value of pc/dc of $9.42{\times}10^{6}$, the MAPD of 318 mW, and the rise and decay time of 10 ms and 9 ms, respectively.

• Journal of Life Science
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• v.21 no.12
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• pp.1659-1665
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• 2011

In Citrus, an $F_1$ segregation population of 150 plants was constructed from a cross between 'Kiyomi' (C. unshiu ${\times}$ C. sinensis) carrying the male sterility trait and 'Jinkyool' (C. sunki). Sequence-related amplification polymorphism (SRAP) combined with bulked segregant analysis was used to develop markers linked to male fertility. In the $F_1$ population, 66 out of 150 seedlings had aborted anthers and the ratio of male sterile plants to fertile plants in the progenies matched the expected Mendelian segregation ratio of 1:1 ($x^2$ =2.16 at p=0.05). From the profiling of the 197 SRAP primer sets, three SRAP primer sets (F4/R27, F39/R60, and F15/R37) that were closely linked to the target trait were identified and successfully converted into a sequence characterized amplified region (SCAR) marker for selection of male fertility in citrus. The SCAR marker, using the pMS 33U/pMS 1462L primer set specifically, produced a single 1.4-Kb fragment that was linked to male fertility. Our results suggested that this SCAR marker can be useful for marker-assisted selection of male sterile individuals in breeding $F_1$ progenies in Citrus.

• Journal of the Korean Society of Radiology
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• v.15 no.7
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• pp.975-982
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• 2021

The purpose of this study is to evaluate the effect on the phantom for magnetic resonance imaging located nearby by partially shielding RF with a mesh made thinner than hair composed of copper, black metal, and polyester using metallic materials of titanium, which are commonly used for esophageal stents and implants in the body. Magnetic resonance images according to field of view (FOV) were analyzed in the Spin Echo T1 weighted images of TR 500 ms, TE 20 ms, NEX 1, and slice thickness 5mm using a Cardiac coil of 3T Achieva X-series. Aliasing artifact did not occur in FOV 304 mm × 304 mm, but it occurred in 250 mm × 250 mm and 170 mm × 170 mm. In FOV 170 mm × 170 mm, when a mesh was not used, the SNR was measured with 78.23, and when separated by standing a mesh in the middle, it was 215.05, and when completely shielded with a mesh, the SNR was 366.44. In addition, when completely shielded with a mesh, the aliasing artifact was also removed, and signal intensities on the left, middle and right of the image were also able to obtain homogeneous images compared to the previous two cases. In conclusion, if RF is partially shielded with a mesh, aliasing artifact can be removed, and magnetic resonance images with excellent image resolution and homogeneity can be obtained using a small FOV.