• Applied Chemistry for Engineering
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• v.21 no.1
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• pp.81-86
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• 2010

On adsorbing carbon monoxide (CO) on the silica supported ruthenium/iron alloy ($Ru/Fe-SiO_2$) samples above mole ratio 9/1 of Ru/Fe five bands ($2138.7{\sim}2142.5cm^{-1}$, $2067.3{\sim}2073.1cm^{-1}$, $1976.7{\sim}2017.2cm^{-1}$, $1737.9{\sim}1799.3cm^{-1}$, $1625.7cm^{-1}$) were observed, and in $Ru/Fe-SiO_2$ samples below mole ratio 8/2 of Ru/Fe two bands ($1934.0{\sim}1990.2cm^{-1}$, $1625.7cm^{-1}$) were observed. The $2138.7{\sim}2142.5cm^{-1}$ bands, the $2067.3{\sim}2073.1cm^{-1}$ bands, and the $1988.3{\sim}2030.7cm^{-1}$ bands may be ascribed to stretching vibrations of CO molecules lineally bonded to the Ru atoms on supported Ru/Fe cluster surface, the $1737.9{\sim}1799.3cm^{-1}$ bands to stretching vibrations of CO molecules bridge bonded to the Ru atoms on supported Ru/Fe cluster surface or to stretching vibrations of CO molecules bonded to the Ru atoms on high Miller index planes, and the $1934.0{\sim}1990.2cm^{-1}$ bands to stretching vibrations of CO molecules lineally bonded to the Fe atoms on supported Ru/Fe cluster surface. The absorbances of the $1934.0{\sim}1990.2cm^{-1}$ bands in $Ru/Fe-SiO_2$ samples gradually increased with the increases of Ru/Fe mole ratio below the ratio of 8/2. This phenomena may be ascribed to the increases of Fe concentration of surface compared with the one of the sample and to the increases of surface area of supported Ru/Fe cluster according as increase of Ru/Fe mole ratio below the ratio of 8/2 compared with the $Fe-SiO_2$ sample.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.49-55
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• 2016

Background: For the purpose of baseline data collection and enhancement of environmental monitoring the distribution studies of $^{137}Cs$ and $^{90}Sr$ in the soil of Uljin province was performed and the relation between surface soil activities and soil properties (pH, TOC and median of the surface soil) was analyzed. Materials and Methods: For 14 spots within 10 km from the NPP surface soil samples were collected and soils for depth profile were sampled for 3 spots in April 2011. Using ${\gamma}$-ray spectrometry with HPGe detector, the concentrations of $^{137}Cs$ were determined and the concentrations of $^{90}Sr$ were measured by counting ${\beta}$-activity of $^{90}Y$ (in equilibrium with $^{90}Sr$) in a gas flow proportional counter. Results and Discussion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ were $<0.479-39.6Bq{\cdot}(kg-dry)^{-1}$ (avg. $7.51Bq{\cdot}(kg-dry)^{-1}$) and $0.209-1.85Bq{\cdot}(kg-dry)^{-1}$ (avg. $0.74Bq{\cdot}(kg-dry)^{-1}$) which were similar to the reported values from other regions in Korea. The activity ratio of $^{137}Cs$ to $^{90}Sr$ in surface soils was around 9.67, which is much bigger than the initial value of 1.75 for worldwide fallouts because of faster downward movement of $^{90}Sr$ after fallout than that of $^{137}Cs$. For depth profile studies soils were collected down to 40 cm depth for the locations of Deokgu, Hujeong and Maehwa. The $^{137}Cs$ concentration distribution of the first two showed maximum values at top soils and decreased rapidly in exponential manner, while $^{90}Sr$ showed two local maximum values for soils near top and about 30 cm depth. Through linear fittings between the $^{137}Cs$ and $^{90}Sr$ concentrations of surface soil and pH, TOC and median of the surface soil, the only probable relationship obtained was between $^{137}Cs$ and TOC (determination coefficient $R^2=0.6$). Conclusion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ in Uljin were similar to the reported values from other regions in Korea. The only probable relationship obtained between activities and soil properties was between $^{137}Cs$ and TOC.

• Journal of Preventive Medicine and Public Health
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• v.27 no.1 s.45
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• pp.25-43
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• 1994

To estimate the factors to the inclination of the criminal violence, the content of trace minerals and toxic metals in the scalp hair were measured during the period from May 1992 to October 1992. One hundred eleven violent and 89 nonviolent criminal inmates of Taegu Correctional Institute were selected. The inmates of violent criminals were imprisoned by murder, robber, rape, injury and violent acts. Those of nonviolent criminals were swindle, larceny, and adultery and had no history of institutional violence. The contents of two toxic metals (cadmium, lead) and five trace minerals (Cu, Fe, Zn, Mg, Na) were determined by an atomic absorption spectrophotometer (IL. 551). The contents of cadmium and lead in hair of violent criminals were significantly higher as $0.56{\pm}0.14ppm,\;11.53{\pm}3.32ppm$, respectively, than $0.42{\pm}0.20ppm,\;9.63{\pm}4.31ppm$ of nonviolent group (p<0.01). But the level of copper was significantly lower than nonviolent group (p<0.05). The factors that had a significant correlation with the inclination of violence in multiple logistic regression analysis were cadmium (odds ratio=98.09), unmarried (odds ratio=0.39), many times of criminal history(odds ratio=1.57) and residence of rural area (odds ratio=0.44). The results suggest that the sub-toxic contents of cadmium and lead in the hair may be of potential effect on behavior, and the mineral analysis may be an important adjunctive diagnostic procedure. Further studies into this problem are necessary.

• Korean Journal of Remote Sensing
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• v.35 no.2
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• pp.251-263
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• 2019

Sentinel-2 Multi Spectral Instrument(MSI) launched by the European Space Agency (ESA) offered high spatial resolution optical products, enhanced temporal revisit of five days, and 13 spectral bands in the visible, near infrared and shortwave infrared wavelengths similar to Landsat mission. Landsat satellite imagery has been applied to various previous studies, but Sentinel-2 optical satellite imagery has not been widely used. Currently, for global coverage, Sentinel-2 products are systematically processed and distributed to Level-1C (L1C) products which contain the Top-of-Atmosphere (TOA) reflectance. Furthermore, ESA plans a systematic global production of Level-2A(L2A) product including the atmospheric corrected Bottom-of-Atmosphere (BOA) reflectance considered the aerosol optical thickness and the water vapor content. Therefore, the Sentinel-2 L2A products are expected to enhance the reliability of image quality for overall coverage in the Sentinel-2 mission with enhanced spatial,spectral, and temporal resolution. The purpose of this work is a quantitative comparison Sentinel-2 L2A products and fully simulated image to evaluate the applicability of the Sentinel-2 dataset in cultivated land growing various kinds of crops in Korea. Reference image of Sentinel-2 L2A data was simulated by airborne hyperspectral data acquired from AISA Fenix sensor. The simulation imagery was compared with the reflectance of L1C TOA and that of L2A BOA data. The result of quantitative comparison shows that, for the atmospherically corrected L2A reflectance, the decrease in RMSE and the increase in correlation coefficient were found at the visible band and vegetation indices to be significant.