• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.05a
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• pp.23-27
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• 2005

Electrogenerated chlorine leaching of used printed circuit board was Investigated in hydrochloric acid solution. The used printed circuit board contained about 45% of metal component, in which copper was about 84%. The leaching rate was greatly effected by current density and agitation. Utilization of electrogenerated chlorine was enhanced by increasing agitation and lowering current density. Leaching of copper was suppressed, while the minor metal elements, such as aluminum, lead, and tin, dominated the leaching at the initial stage.

• Natural Product Sciences
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• v.22 no.1
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• pp.60-63
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• 2016

The study is a pioneering effort to determine the mineral, nutritional, and phytochemical composition and phenolic content and to determine the free radical scavenging activity of Gigantochloa levis (Blanco) Merr, a native bamboo species (locally known as "bolo") in the Philippines. Proximate analysis showed that air-dried G. levis leaves contain 15.8% ash, 22.6% crude protein, 1.2% crude fat, 29.3% crude fiber, and 19.7% total sugar. Phytochemical tests indicated the presence of diterpenes, triterpenes, saponins, phenols, tannins, and flavonoids in both the ethanolic and aqueous leaf extracts, while phytosterols were only detected in the ethanolic extract. Folin-Ciocalteu assay determined the total phenolic content in gallic acid equivalents (GAE) to be $85.86{\pm}3.71$ and $32.32{\pm}1.01mg\;GAE/100g$ dried sample for the ethanolic and aqueous extracts, respectively. The total phenolic content in quercetin equivalents (QE) was $74.44{\pm}3.11$ and $29.43{\pm}0.85mg\;QE/100g$ dried sample for the ethanolic and aqueous extracts, respectively. The radical scavenging activity of the different solvent fractions containing varying concentrations of the extract was determined using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. The ethyl acetate and 1-butanol fractions were found to have the highest radical scavenging activity. Mineral analysis via Energy Dispersive X-Ray Spectrometry (EDS) of the ash of G. levis leaves showed that Si is the major component, followed by K and Mg. These results point to the potential of G. levis leaves as a source of minerals and bioactive compounds with medicinal value.

• Journal of Ginseng Research
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• v.26 no.4
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• pp.196-201
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• 2002

This study was carried out to compare the contents of saponins and minerals component in Korean Red Ginseng (Heaven, Earth, Good grade), North Korean Red Ginseng (Heaven, Earth, Good grade), Japanese Red Ginseng (Oonju, Sinju 1, 2, 3 grade, respectively) and Chinese Red Ginseng (Seokju, Gilim, 1, 2, 3 grade, respectively). Crude saponin contents were different on according to the grade and cultivation area, and was 3.05-3.76% in Korean Red Ginseng, 2.09-3.21% in North Korean Red Ginseng, 2.82-3.71% in Chinese Seokju Red Ginseng, 2.72-3.62% in Chinese Gilim Red Ginseng, 2.11-2.44% in Japanese Oonju Red Ginseng, 2.18-2.87% in Japanese Sinju Red Ginseng, and the amount of ginsenoside-Rb1, -Re, -Rg$\_$1/ in Korean Red Ginseng were higher than those of North Korean, Chinese and Japanese Red Gingsen. The contents of mineral components were similar, but La, Na and Sn component in Korean Red Ginseng showed the higher amount than those of other Red Ginsengs.

• Culinary science and hospitality research
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• v.24 no.1
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• pp.13-23
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• 2018

This study aimed to investigate the characteristics of 3 pre-treatment of mealworm(Tenebrio molitor), and offer basic research data through appropriate pre-treatment method based on the component analysis result. This study was preparing the control group sample No.0(not contain mealworm), and the other sample (Sample No.1,2,3) was using the mealworm prepared in each of the three methods. By using the sample, this study conducted an inspection for component analysis, mineral contents, pH, color value, total amount polyphenols, DPPH radical scavenging activity, reducing power, acceptance test. Each experiments are three times repeated and validated following the one-way ANOVA analysis to verify a significant difference. Acceptance test conducted by 50 consumers indicate consumption decision for sunsik. using the seven point scale, assessment for appearance, flavor, taste, texture, overall acceptance. The research findings showed that sample containing sauted mealworm(SE2) is higher preference and significant in antioxidant activity(total amount polyphenols, DPPH radical scavenging activity, reducing power). Therefore, it is better to use sauted. The result of this study suggest that sauted mealworm is good ingredient for consumer acceptability and functionality of sunsik. According to results of the study, it is suggested to make better use of food, and provide food developer with meaningful date for market targeting. In addition, this study also provides the information for improving awareness of edible insect.

• Journal of Soil and Groundwater Environment
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• v.27 no.1
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• pp.50-59
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• 2022

There are several methods for separating the baseflow from the hydrograph, and graphical methods (GM) have mostly been used. GMs are those that separate the baseflow from the direct flow simply by connecting rising point with inflection point or points related to some duration from a hydrograph. Environmental tracer method (ETM) is another tool researched and developed under several conditions to estimate the groundwater recharge. The goal of this study is to separate the baseflow component from a storm hydrograph by applying various GMs and ETM, and to compare their results. The baseflow component estimated by ETM was different from the results by GMs in terms of their shapes of fluctuation and flow rates. Another important feature is that the form of the baseflow to which ETM is applied is similar to that of a storm hydrograph. This similarity is presumed to be due to the selection of tracer that respond quickly to rainfall.

• Economic and Environmental Geology
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• v.36 no.3
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• pp.201-212
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• 2003

Recently, the ability of earthquake detection in the Kyungsang Basin of southeastern Korean Peninsula is greatly improved since seismic stations including seismic network of KIGAM(Korea Institute of Geoscience and Mineral Resources) have been significantly increased. However, a large number of signals from explosions are recorded because of frequent medium to large chemical explosions. The discrimination between natural earthquakes and explosions in the Basin has become an important issue. High frequency local records from 43 earthquakes and 43 explosions with comparable magnitude are selected to establish a reliable discrimination technique in the Basin. Several discrimination techniques in spectral domain using spectral amplitude ratios among Pg, Sg, and Lg waves are widely examined with tile selected data. Among them the Pg/Lg spectral ratio method is appeared to be a good discrimination technique to improve the discrimination power. Multivariate discriminant analysis is also applied to the Pg/Lg spectral ratios. The discrimination power of the Pg/Lg ratios for distance corrected three component record compared to uncorrected vertical component one shows distinct improvement. In the frequency band 4 to 14 Hz, Pg/Lg spectral ratio for distance corrected three component record provides discrimination power with a total misclassification probability of only 0.89%.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.725-732
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• 2013

To identify the food component characteristics of seven edible pufferfishes (five wild pufferfishes including striped puffer Takifugu xanthopterus; eyespot puffer Takifugu chinensis; purple puffer Takifugu porphyreus; rough-backed puffer Lagocephalus wheeleri; and grass puffer Takifugu niphobles; and two cultured pufferfishes including yellow puffer Takifugu obscurus, and tiger puffer Takifugu rubripes) in Korea, the proximate, fatty/amino acid, chemical and taste compositions were investigated. The proximate compositions were not significantly different among the sampled pufferfishes, whereas grass puffer had lower moisture and crude lipid levels contents, and higher crude protein and ash contents than the other species. The total amino acid levels in wild and cultured pufferfishes were 14,941.6-16,427.9 mg/100 g, and the major amino acids were aspartic acid, glutamic acid, glycine, alanine, leucine, lysine and arginine. Regarding the fatty acid and mineral compositions, the major fatty acids included 22:6n-3, 16:0, 18:1n-9, 20:5n-3, 18:0, 20:4n-3, and 22:5n-3 in that order, and there was a little difference among the sampled pufferfishes. Grass puffer had a higher monoenes ratio, i.e., 16:1n-7 and 18:1n-9, and a lower polyenes ratio than the other pufferfishes. The main minerals detected K, P, Na, S and Ca. Regarding the taste-active compounds, the free amino acid contents of pufferfish extracts were 236.4-428.1 mg/100 g, consisting primarily of taurine, lysine, proline, glycine, alanine and arginine in that order. The amino nitrogen content of the pufferfishes was 84.5-156.4 mg/100 g, and there was a little difference among the species. As for taste intensity, the total taste value of the purple puffer was higher than that of the other pufferfishes.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.3
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• pp.173-177
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• 2001

This study was conducted to investigate a potential utilitization of multivariate statistical analysis(Factor analysis, Discrimination analysis) on interpretation of rice plant lodging reason. Rice plants were sampled in paddy around Taegu city at from 25 to 29 of September in 2000. Mineral nutrient content(phosphate, potassium) of rice plant were significantly higher at 99% level, Silicate content were lower at 95% level in lodged samples than in normal. Plant characteristics associate with lodging(Culm length, second and third internode length, bight of center gravity) were significantly longer in lodged rice plant than in non lodged. Result of Factor analysis were that first principle component were culm length, second(N2) and third internode length(N3), second principle component were Ca content, first internode length(N1) and N3/culm length, third principle component were center gravity length(G) and G/culm length, fourth were nitrogen, phosphate, and potassium content, fifth were N2/culm length, N2+N3/culm length, Sixth was silicate content of rice plant. Linear discriminant equation distinguished lodged rice plants with non lodged rice plants very well. Prediction value was 100%, most explainable variable were phosphate content, culm length and third length.

• Nuclear Engineering and Technology
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• v.45 no.4
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• pp.539-552
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• 2013

To establish an aging management plan considering seawater influx and changes in groundwater within nuclear power plant sites, the characteristics of groundwater flow must be understood. This study investigated the characteristics of groundwater flow within the site and analyzed groundwater level recorded by monitoring wells to evaluate groundwater flow characteristics and elements that affected these characteristics for supplying the information to conduct the appropriate aging management for ensuring the safety of the safety-related structures in Shin Kori Unit 1 and 2. The increase in groundwater level during the wet season results from high sea-level conditions and the large amount of precipitation. As a result of the analysis of groundwater distribution and change characteristics, the site could be divided into a rainfall-affected area and a tide-affected area. First, the rainfall-affected area can further be divided into areas that are affected simultaneously by excavation, backfill, and a permanent dewatering system. Secondly, areas that are not affected by excavation, or the dewatering system, or by structure arrangement and excavation. Analysis of the spectrum for wells affected by tides resulted in confirmation of the M2 component (12.421 hr) and S2 component (12.000 hr) of the semidiurnal tides, and the O1 component (25.819 hr) of the diurnal tides. In the cross-correlation results regarding tides and groundwater levels, the lag time occurred diversely within 1-3 hours by the effect of the well location from sea, the distribution of the backfill material with depth, and the concrete structure.

• Journal of the Mineralogical Society of Korea
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• v.12 no.1
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• pp.43-53
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• 1999

The medical mineral menas a single mineral or a complex of minerals. It is natural material. using the medical action of he major or the minor elements, and traditional medicine stuff which has been used since long time ago. Jusa, cinnabar as the mineral name, is the product of the hydrothermal process. It is used to relax the body and cure high blood pressure, apoplexy and cardiopathy. Jusais the major component of "An shin hwan" and "Woo hwang chung shim hwan" nowadays because it has such an excellent calm effect. In addition, it is used to cure cancers such as esophageal cancer and gastric cancer. Jusa composed of mercuric sulfide causes mercury poisoning such as Minamata disease. It is dealt with mineralogical property and chemical composition medical stuff in Korea and China, as well asmercury poisoning and medical action of Jusa in this study. In order to predct accumulation of the interior of the body of the major and minor elements in Jusa, leaching experiment of Jusa by artificial gastric juice was done as well as thermodynamic reaction modelling to know concentration of each species of body fluid. The minor elements of 24 species such as As, Pb, Cd, a and Fe by leaching reaction of Jusa and artificial gastric juice were leached. We can know the fact that as is less than 1 ppm, Hg is less than 25 ppm and Cd and m are not detected. In addition, mercury exists as species of Hg2+, HgCl+, HgCl2, HgCl3-, HgCl42-, HgClOH, HgS(H2S)2, Hg(HS)3-, HgS22-, HgOH and Hg(OH)2 by reaction modelling between Jusa and artificial gastric juice. The concentration of sulfide complexes is 24.2 ppm and that of others is less than 10 ppm. According to increasing pH, the concentration of HgS(H2S)2, Hg(HS)3+, HgS22- and Hg(OH)2 increases, whereas the concentration of HgCl+, HgCl2, HgCl3- and HgCl42- decreases. Therefore, Jusa is very useful for the development of new medicine because it is possible to predict formation of the body species and species accumulation on mercury known as a toxic element and concentration changes of toxicity and efficiency.city and efficiency.