• Journal of the Mineralogical Society of Korea
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• v.16 no.4
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• pp.307-320
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• 2003

Garnet has been considered as a possible matrix for the immobilization of radioactive actinides. It is expected that Fe­based garnet be able to have the high substitution ability of actinide elements because ionic radius of Fe in tetrahedral site is larger than that of Si of Si­based garnet. Accordingly, we synthesized Fe­garnet with the batch composition of $Ca_{2,5}$C $e_{0.5}$Z $r_2$F $e_3$ $O_{12}$ and $Ca_2$CeZrFeF $e_3$ $O_{12}$ and studied their phase relations and properties. Mixed samples were fabricated in pellet forms under the pressure of 400 kg/$\textrm{cm}^2$ and were sintered in the temperature range of 1100∼140$0^{\circ}C$ in atmospheric conditions. Phase identification and chemical composition of synthesized samples were analyzed by XRD and SEM/EDS. In results, where the compounds were sintered at 130$0^{\circ}C$, we optimally obtained Fe­garnets as the main phase, even though some minor phases like perovskite were included. The compositions of Fe­garnets synthesized from the batch compositions of $Ca_{2,5}$C $e_{0.5}$Z $r_2$F $e_3$ $O_{12}$ and $Ca_2$CeZrFeF $e_3$ $O_{12}$, are $Ca_{2.5­3.2}$C $e_{0.3­0.7}$Z $r_{1.8­2.8}$F $e_{1.9­3.2}$ $O_{12}$ and $Ca_{2.2­2.5}$C $e_{0.8­1.0}$Z $r_{1.3­1.6}$ F $e_{0.4­.07}$ F $e_{3­3.2}$ $O_{12}$, respectively. Ca contents were exceeded and Ce contents were exceeded or depleted in 8­coodinated site, comparing to the initial batch composition. These results were caused by the compensation of the difference of ionic radius between Ca and Ce.

• Journal of the Mineralogical Society of Korea
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• v.22 no.3
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• pp.177-189
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• 2009

Iron (oxyhydr)oxides commonly form as secondary minerals of high reactivity and large surface area resulting from alteration and weathering of primary minerals, and they are efficient sorbents for inorganic and organic contaminants. Accordingly, they have a great potential in industrial applications and are also of substantial interest in environmental sciences. Goethite (${\alpha}$-FeOOH) is one of the most ubiquitous and stable forms of iron (oxyhydr)oxides in terrestrial soils, sediments, and ore deposits, as well as a common weathering product in rocks of all types. This study focused on adsorption reaction as a main mechanism in scavenging arsenic using goethite. Goethite was synthesized in the laboratory to get high purity, and a variety of mineralogical and physicochemical features of goethite were measured and related to adsorption characteristics of arsenic. To compare differences in adsorption reactions between arsenic species, in addition, a variety of experiments to acquire adsorption isotherm, adsorption edges, and adsorption kinetics were accomplished. The point of zero charge (PZC) of the laboratory-synthesized goethite was measured to be 7.6, which value seems to be relatively higher, compared to those of other iron (oxyhydr)oxides. Its specific surface area appeared to be $29.2\;m^2/g$ and it is relatively smaller than those of other (oxyhydr)oxides. As a result, it was speculated that goethite shows a smaller adsorption capacity. It is likely that the affinity of goethite is much more larger for As(III) (arsenite) than for As(V) (arsenate), because As(III) was observed to be much more adsorbed on goethite than As(V) in equivalent pH conditions. When the adsorption of each arsenic species onto goethite was characterized in various of pH, the adsorption of As(III) was largest in neutral pH range (7.0~9.0) and decreased in both acidic and alkaline pH conditions. In the case of As(V), the adsorption appeared to be highest in the lowest pH condition, and then decreased with an increase of pH. This peculiarity of arsenic adsorption onto goethite might be caused by macroscopic electrostatic interactions due to variation in chemical speciation of arsenic and surface charge of goethite, and also it is significantly affected by change in pH. Parabolic diffusion model was adequate to effectively evaluate arsenic adsorption on goethite, and the regression results show that the kinetic constant of As(V) is larger than that of As(III).

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.1
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• pp.36-44
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• 2010

In order to rehabilitate forest sites damaged by wildfire via natural or artificial restoration, it is important to determine right tree species, which can acclimate to biogeoclimatic environment at the sites. The objectives of this study were to develop site index equation of different tree species for estimating forest productivity and to provide information on species selection for post-wildfire restoration. Site index equation was developed based on environmental information from wildfire damaged areas in Gangneung, Goseong, Donghae, and Samcheok, where were located in east coastal areas of South Korea. Despite the small numbers (4~5) of environmental variables used for the development of the site index equations, statistical analysis (e.g. mean difference, standard deviation of difference, and standard error of difference) showed relatively low bias and variation, suggesting that those equations can provide relatively high capability of estimation and practical applicability with high effectiveness. The small numbers of the variables enabled the model to be applied in a wide range of usages including determination of appropriate tree species for post-wildfire restoration. The estimation of forest site productivity showed the possibility of large distribution in east coastal region as the best site for Korean ash (Fraxinus rhynchophylla) and original oak (Quercus variabilis) that can be used for firebreak in the region. These results imply that damages by forest fire can be reduced significantly by replacing existing pure coniferous forests in the area with ones dominated by broad-leaved deciduous stands, which can play an important role as fire break and/or prevent a transition from surface fire to crown fire.

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.174-181
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• 1998

In four citrus grow of Satsuma mandarin (rootstock of trifoliate orange) including two grove of organical management and two groves of conventional management, spores of arbuscular mycorrhizal(AM) fungi were identified and seasonal changes in spore density in soils and AM colonization of citrus roots were investigated. AM colonization in weeds found in the groves were also examined. Three species of Glomus (G.deserticola, G. vesiculiferum, G. rubiforme ) and one unknown species of Acaulospora were observed in all of the groves. Annual mean density of AM fungal spores were in the range of 10,000${\sim}$40,000 per 100g soil with more spores in the organically-managed groves. The least spores were observed in December in all groves, and the most spores in April in the organically-managed groves while in February or April in the conventionally- managed. Annual mean AM colonization more 27% of citrus root were observed in the organically-managed with the high peaks in April and October and the minimum in August, while mean colonization less than 15% in the conventionally-managed with the peak in February and the minimum in different times depending on groves and years. AM colonization corresponded to a sigmoidal curve consisting of a laf phase during winter and a subsequent increase in spring, then succeeded by a maximum, and then a decrease at the end of vegetation. Fungal spore density and AM colonization showed a parallel pattern during the sample period. The seasonality appeared to be related more to the phenology of the plant than to the soil factors. Generally more spore density and AM colonization were found in organically managed groves. AM colonization was not correlated with available P and organic matter content in soil in this field investigation. Among sixteen weed species found in the groves, Astrogalus sinicus of Leguminosae, Portulaca oleracea of Portulacaceae showed high colonization in all groves and they can be considered as a source of inoculumn and host plants for propagation of AM fungi.

• Journal of the Korean Society of Food Culture
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• v.18 no.4
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• pp.333-345
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• 2003

We conducted a survey on Japanese women's consciousness of food culture and their traditional food consumption by self filling-out questionnaire during January, 2000 for the period of a month, For the survey we selected 250 women residing in Kyoto, Japan. For the statistic work we used SAS package system, and t-test, $\cal{X}^2-test$ and Duncan's multiple range test were also used to verify the results significance. The purpose of this survey lies in gathering a basic data on the comparative direction of Korean and Japanese women's food culture in the future 1. Comparing the preferred food purchase place, In case of Korean women, traditional market was comparatively more preferred while Japanese women relatively preferred convenience store (p<0.001). 2. In case of Japanese women, they answered there is no difference from ordinary days on New Year's Day (71%) and Christmas (40%) while 38% answered they prepare food at home. 40% said they prepare food on parents-in-law's birthday, and 41% said no difference from ordinary days. 52% said they prepare food at home on husband's birthday. For their own birthday, 32% said yes to preparing food at home while 45% said no difference and 22.3% said eating out. For children's birthday 65% said preparing at home, 16.3% said no difference and 14.9% said eating out. 3. Comparing the conception on traditional food, Korean women answered 'complicated' (77%) most while 'simple' (5%) least, which indicates their demands for simplified recipes. In case of Japanese women, 'complicated' (44%) was most while 'scientific' (6%) was least which indicates their demands for scientific way of recipes. There were differences shown by age (p<0.001) and the older the more said 'simple' or 'logical' (p<0.01). 4. As the reason for the complicity of traditional food recipes, Koreans said 'too many hand skill' (60%) most while 'too many spices' (8%) least. For Japanese, 'various kind of the recipe' (55%) was most while 'too many hand skill' (7%) was least. There were significant differences shown by academic background (p<0.01) and income(p<0.01), and the lower the academic background, the more said 'too many spices' as the reason for the complicity in making traditional food. Generally, the lesser the income, the more tendency to say 'various kinds of the recipe'. 5. In case of Koreans, 'the recipe is difficult' (56%) was high while 'uninterested' (9%) was low in answer which showed differences by academic background (p<0.05), and in case of Japanese, 'no time to cook' (44%) was high while 'uninterested' (7%) was low. 6. The following is the reasons for choosing traditional food as a snack for children. In case of Koreans, they answered as 'traditional food' (34%), 'made from nutrious and quality materials' (27%), 'for education' (22%) and 'suites their taste' (17%) revealing 'traditional food' is highest. In case of Japanese, it was revealed in the order of 'made from nutrious and quality materials' (36.3%), 'traditional food' (25.2%), 'suites their taste' (22.6%), 'for education' (12.8%) and 7. Comparing the most important thing for the popularization of traditional food in the world, Koreans answered 'taste and nutrition' (45%) most while 'shape and color' (6%) least. In case of Japanese, 'taste and nutrition' (75%) was answered most while 'hygienic packaging' (4%) was least. Both considered 'taste and nutrition' as most important thing for the popularization of traditional food in the world. 8. In case of Koreans, they answered they learn how to make traditional food 'from mother' (47%), 'media' (18%), 'school' (15%), 'from mother-in-law' (14%), 'private cooking school' (4%) and 'close acquaintances' (2%). In case of Japanese, they said mostly learn 'from mother', but it was also shown that the lower the academic background the lesser the tendency of learning 'from mother' but 'from school' (p<0.001). 9. About the consumption of traditional fermented food, Koreans said they make kimchi (90%), pickled vegetables (39%), soy sauce (33%), bean paste (38%), salted fishery (12%) and traditional liquors (14%) at home while 67% for salted fishery and 48% for traditional liquors answered they buy rather than making at home. On the other hand, Japanese answered they mostly buy kimchi (60%), soy sauce (96%), bean paste(91%), natto(92%), salt fermented fish foods (77%) and traditional alcoholic beverage (88%) to eat. This difference was shown very distinct between Korean and Japanese women (p<0.001). 10. About the most important thing in food, Koreans answered in the order of 'liking and satisfaction' (33%), 'for health' (32%), 'for relieve hunger' (18%) and 'convenience' (17%). In case of Japanese, it was revealed in the order of 'for health' (61%), 'liking and satisfaction' (20%), 'to relieve hunger' (16%) and 'convenience' (3%). This shows that Japanese women take comparably more importance to health than Korean women. The conception of food was shown different between Korean and Japanese women (p<0.001), and Koreans showed level 4-5 of food culture while Japanese showed level 5.

• Korean Journal of Ecology and Environment
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• v.45 no.2
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• pp.218-231
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• 2012

The objectives of this study were to evaluate the physico-chemical water quality, trophic and tolerance guilds in the control ($C_o$) and impacted streams of the abandoned mine, along with the ecological health, using a multimetric health model and physical habitat conditions of Qualitative Habitat Evaluation Index (QHEI), during the period of three years, 2005~2007. Also, eco-toxicity ($EE_t$) enclosure tests were conducted to examine the toxic effects on the outflows from the mine wastewater, using the sentinel species of Rhynchocypris oxycephalus, and we compared the biological responses of the control ($C_o$) and treatment (T) to the effluents through a Necropybased Health Assessment Index ($N_b$-HAI). Tissue impact analysis of the spleen, kidney, gill, liver, eyes, and fins were conducted in the controlled enclosure experiments (10 individuals). According to the comparisons of the control ($C_o$) vs. the treatment (T) in physicochemical water quality, outflows from the abandoned mine resulted in low pH of 3.2, strong acid wastewater, high ionic concentrations, based on an electrical conductivity, and high total dissolved solid (TDS). Physical habitat assessments, based on Qualitative Habitat Evaluation Index (QHEI) did not show any statistical differences (p>0.05) in the sampling sites, whereas, the $M_m$-EH model values in a multimetric ecological health ($M_m$-EH) model of the Index of Biological Integrity (IBI), using fish assemblages, were 16~20 (fair condition) in the control and all zero (0, poor condition) in the impacted sites of mine wastewater. In addition, in enclosure eco-toxicity ($EE_t$) tests, the model values of $N_b$-HAI ranged between 0 and 3 in the controls during the three years, indicating an excellent~good condition (Ex~G), and were >100 (range: 100~137) in the impacted sites, which indicates a poor condition (P). Under the circumstances, organ tissues, such as the liver, kidney, and gills were largely impaired, so that efficient water quality managements are required in the outflow area of the abandoned mine watershed.

• Economic and Environmental Geology
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• v.36 no.4
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• pp.257-268
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• 2003

The Cretaceous magmatism in the Gyeongsang Basin, Korea, led to the formation of two contrasting metallogenic provinces: the Haman-Gunbug-Goseong(-Changwon) (HGGC) and the Euiseong (EU). The mineralization in the HGGC metallogenic province represents copper, gold and iron of porphyry-related deposits that display close relationships in time and space with subvolcanic granitoids. Much of copper-gold-forming events in this province are consistently constrained to the period between ca. 89 and 81 Ma. The hydrothermal systems of copper-gold vein deposits in the HGGC province are associated with ore-forming fluids of high to intermediate temperature (300∼50$0^{\circ}C$) with high salinity (20∼55 equiv. wt. % NaCl). The ore-forming fluids become progressively more diluted by the incorporation of decreased quantities of magmatic water further from the nearby intrusion, suggesting significant input and fluid mixing of a meteoric water component to the magmatic fluids during the late stage of geothermal systems. In contrast, the EU metallogenic province is characterized by polymetallic vein deposits that are consistently constrained to a period of 78∼60 Ma. The geothermal systems of polymetallic vein deposits in the EU province are derived from a narrow range of intermediate temperature (200∼40$0^{\circ}C$) with relatively low salinity(1∼7 equiv. wt.% NaCl). It may represent a mixed fluid of magmatic and meteoric waters. The base-metal mineralization in the Gyeongsang Basin shows a close spatial and temporal distinction between the proximal environment derived from shallow-level granitoids in the southwestern HGGC province and the distal condition derived from volcanic environments in the northwestern EU province.

• Analytical Science and Technology
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• v.23 no.6
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• pp.531-536
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• 2010

A quantitative analytical method has been established for the measurement of inosine 5'-monophosphate dehydrogenase (IMPDH) activity in human peripheral blood mononuclear cells (PBMCs) by ion-pair reversed-phase high performance liquid chromatography equipped with ultraviolet detection (HPLC/UV). IMPDH is a ${\beta}$-nicotinamide adenine dinucleotide hydrate (NAD+)-dependent dehydrogenase in which the enzyme converts inosine 5'-monophosphate (IMP) into xanthosine 5'-monophosphate (XMP). Its activity was measured by quantifying a HPLC chromatogram corresponding to XMP produced during the incubation of lysed PBMCs with IMP as a substrate and $NAD^+$ as a coenzyme. XMP produced was detected at a wavelength of 260 nm. The mobile phase was composed of a mixture of 37 mM potassium dihydrogen phosphate containing 7 mM tetra-n-butylammonium hydrogen sulfate adjusted to pH 5.5 and methanol (85:15, v/v) with a flow rate of 1 mL/min. The calibration curve was linear ($r^2$=0.999999) in the range of $0.2-50.0\;{\mu}M$ and the limit of quantification (LOQ) was $0.2\;{\mu}M$. The intra- and inter-day precisions were between 0.88-1.47% and 0.85-5.24%, respectively. The intra- and inter-day accuracies were between 98.74-99.99% and 99.95-101.65%, respectively. IMPDH activity in 11 Korean healthy volunteers ranged from 18.29 to 36.60 nmol/h/mg protein (mean = $27.70{\pm}6.28\;nmol/h/mg$ protein).

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.319-324
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• 2011

This study was conducted to analyze demerits of the sire evaluation system using annual earnings and to examine relationship between annual earnings and finish time in home-produced thoroughbred racehorses. The average number of progenies and number of starts per sire were 34 heads and 221 times, respectively. On the other hand, the number of progenies with the average age of 2 years and the number of starts were 9 heads and 25 times, respectively. The earnings of the horses with the age of 2 years accounted for 8.3% of annual earnings. The simple correlation coefficient between the number of progenies and the number of starts in annual earnings were 0.922 and 0.934, respectively. The correlation coefficient between the number of progenies and the number of starts was very high (0.985). The number of progenies and starts of sires for the first year of test career were very low (6 heads and 17 times), and there was very close relationship between number of progenies and annual earnings by the year of test career. The number of progenies was over 40 heads during the first 4 years of test career, and as the number of progenies increased the average earning index increased. The average earning index of sires with less than 30 progenies was lower than 1.00. When the number of progenies was less than 10, the average earning index was in the range of 0.06~0.13, indicating that the number of progenies affects much for determining the ranking of sires. The correlation coefficient between breeding value for finish time and annual earnings per start was very high (-0.524~-0.633) compared with other traits.

• Korean Journal of Environmental Agriculture
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• v.16 no.3
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• pp.249-254
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• 1997

The constructed wetland system which is applicable to rural wastewater treatment was examined by pilot plant experiment. Removal rates of nutrients including nitrogen and phosphorus and total coliform were evaluated. The $NH_4\;^+$ concentration of the influent was in the range of 91.57 to 275.88mg/l and the effluent concentration was about 40% lower than the influent. The decreasing of the $NH_4\;^+$ concentration might be due to volatilization, plant uptake, adsorption onto soil particles, and mainly nitrification. However, generally concentrations of $NO_2\;^-$ and $NO_3\;^-$ were increased in the effluents compared to the influent concentrations, which implies that nitrogen components in the system were nitrified. Overall, the average removal rate of the nitrogen was about 5% which seems inadequate as a wastewater treatment system, and this system needs improvement on nitrogen removal mechamism. The removal rate of the phosphorus was quite high and effluent concentration was very low. Reason for high removal rate of the phosphorus might be mainly strong adsorption characteristic onto soil particles. The average removal rate of the total coliforms was about 83%, and main removal mechanisms are thought to be adsorption onto soil and inability to compete against the established soil microflora. From the results of the study, the constructed wetland system needs to be improved in nitrogen removal mechanism for field application.