• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.4
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• pp.15-24
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• 2019

The study was compared for soil chemical and microbial properties as well as growth of the cherry tomato (Lycopersicon esculentum var. cerasiforme) plants environmentally friendly gown for 3 years and 5 years, which had been fertigated with homemade liquid fertilizer (LF) with indigenous microorganism as an additional fertilizer. Treatment included LF with indigenous microorganism for 3 years (3-year IM-LF) and for 5 years (5-year IM-LF), with an effective microorganism for 10 years (EM-LF), which had been applied with 1,000 times of dilution in the farmhouse. IM-LF and EM-LF materials had increased pH pattern for 16 weeks, in particular for increase of 1.2 for EM-LF. IM-LF material contained slightly higher EC but similar level of 0.2 dS/m to EM-LF. For a pot experiment in the greenhouse, IM-LF treatment increased root dry weight of the cherry tomato plants. In the farmhouse experiment, IM-LF treatment increased to 7.5 of soil pH and 8.4 dS/m of EC, indicating high salt accumulation. EM-LF treatment increased to 62 g/kg of soil OM, which would have affected concentrations of macro essential nutrients, including T-N in the soil. However, the optimum soil chemical levels for growth of cherry tomato plants were observed on the IM-LF plots. EM-LF treatment increased number of bacteria and actinobacteria in the soil. EM-LF treatment increased concentrations of macro essential nutrients in the plants, except for P, with similar nutrient concentrations observed between 3-year IM-LF and 5-year IM-LF-treated plants. Leaf SPAD and PS II levels decreased in the plants treated with 3-year IM-LF. EM-LF treatment increased leaf width and length, number of leaves, canopy area, plant height, and stem diameter in the mid-term stage of growth, which were not significantly different between the treatments. EM-LF treated-plants had two times higher leaf dry weight than those of values observed on the IM-LF plants, which was the opposite result observed on the number of fruit.

• Korean Journal of Food Science and Technology
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• v.20 no.4
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• pp.576-584
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• 1988

Neutral detergent fiber(NDF) were extracted from the Nampung, Milyang #23, Whasung and Jinhung varieties of rice by neutral detergent fiber method. To determine the properties of NDF three factors were measured : water-binding capacity(WBC), Fe-binding capacity and sodium taurocholate binding with NDF. The average WBC of NDF was $5.60{\pm}0.87gH_2O/g$ NDF, and the average Fe-binding capacity ranged from 24.63% at pH 5.0 to 19.6% at pH 6.0 and 48.98% at pH 7.0. Binding of sodium taurocholate with NDF was determined in vitro using C-14 labeled sodium taurocholate at 100M sodium taurocholate concentrations. NDF binding of Jinhung was 27.87 while Nampung, Milyang #23 and Whasung measured 32% each. When sodium taurocholate concentrations were raised from $40{\mu}M\;to\;240{\mu}M$ the tendency of binding increased as the concentrations increased, but not linearly.

• Economic and Environmental Geology
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• v.56 no.6
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• pp.729-744
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• 2023

The value of lithium has significantly increased due to the rising demand for electric cars and batteries. Lithium is primarily found in pegmatites, hydrothermally altered tuffaceous clays, and continental brines. Globally, groundwater-fed salt lakes and oil field brines are attracting attention as major sources of lithium in continental brines, accounting for about 70% of global lithium production. Recently, deep groundwater, especially geothermal water, is also studied for a potential source of lithium. Lithium concentrations in deep groundwater can increase through substantial water-rock reaction and mixing with brines. For the exploration of lithim in deep groundwater, it is important to understand its origin and behavior. Therefore, based on a nationwide preliminary study on the hydrogeochemical characteristics and evolution of thermal groundwater in South Korea, this study aims to investigate the distribution of lithium in the deep groundwater environment and understand the geochemical factors that affect its concentration. A total of 555 thermal groundwater samples were classified into five hydrochemical types showing distinct hydrogeochemical evolution. To investigate the enrichment mechanism, samples (n = 56) with lithium concentrations exceeding the 90th percentile (0.94 mg/L) were studied in detail. Lithium concentrations varied depending upon the type, with Na(Ca)-Cl type being the highest, followed by Ca(Na)-SO₄ type and low-pH Ca(Na)-HCO₃ type. In the Ca(Na)-Cl type, lithium enrichment is due to reverse cation exchange due to seawater intrusion. The enrichment of dissolved lithium in the Ca(Na)-SO₄ type groundwater occurring in Cretaceous volcanic sedimentary basins is related to the occurrence of hydrothermally altered clay minerals and volcanic activities, while enriched lithium in the low-pH Ca(Na)-HCO₃ type groundwater is due to enhanced weathering of basement rocks by ascending deep CO₂. This reconnaissance geochemical study provides valuable insights into hydrogeochemical evolution and economic lithium exploration in deep geologic environments.

• Journal of fish pathology
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• v.36 no.2
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• pp.293-302
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• 2023

This study evaluated the acute toxicity induced by oxolinic acid (OA), neomycin-oxytetracycline combination (NEO-OTC) and florfenicol (FF) administered to guppy (Poecilia reticulata) by comparing standard formulations with commercial preparations (COOaqua curinpotion, COOaqua terafinpotion and COOaqua profenpotion, respectively) for ornamental fish at concentrations of 2-4%. NEO-OTC exhibited the highest acute toxicity in guppy, with no difference observed between the pstandard formulation and commercial preparation (LC₅₀ = 126.08 mg/L and 112.44 mg/L, respectively). OA acute toxicity was assessed in the form of sodium salt, with an LC₅₀ of 504.61 mg/L for the standard formulation and a slightly increased toxicity of 316.11 mg/L for the commercial preparation. In contrast, no mortality was observed during the 96-hour exposure period with the standard formulation in the form of oxolinic acid. The acute toxicity of FF was measured to be above 1,000 mg/L for the standard formulation; however, the commercial preparation significantly increased to 158.53 mg/L. These results indicate that toxicity can significantly increase in commercial formulations, especially those with low levels of active ingredients. This is presumed to be attributed to the organic solvents or solubilizing agents present in the commercial preparations, which may enhance toxicity. Additionally, guppy infected with Aeromonas salmonicida were effectively protected against mortality by administering OA, NEO-OTC and FF at concentrations of 50 mg/L, 100 mg/L and 15 mg/L, respectively, for 2 hours and at half the dose for 24 hours. This result indicates that liquid formulations containing low concentrations of antibiotics may partially increase toxicity, but there is no problem in effectively treating diseases in ornamental fish.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.31-38
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• 1985

To learn more about the productivity of edible meat and its functional properties of spent hen, 60 White Leghorn fowls at 20 month of age were randomly divided into 6 groups, 10 hen for each group, and processed. As the productivity of edible meat, the yield of dressed carcass, giblets, cut-up meat, and breast and leg (thigh and drustick) muscles were determined. The approximate chemical composition, the content of salt-soluble protein, the emulsifying capacity and W.H.C. of breast and leg muscle were measured as the functional properties. The results were summarized as follows. 1. The average live weight of spent hen was 1,576.7g from which the yield of dressed carcass and giblets were 998.9g(63.4%) and 75.3g(4.8%) respectively. It means the yield of ready-to-cook form was 1,074.2g(68.2%) and the inedible byproducts was 502.5g (31.8%). 2. The average, weight of each part of cut-up chicken were: neck 41.0g(4.1%), wings 135.9g (13.6%), breast 276.7g (27.7%), legs 323.6g (42.4%). back 176.1g(17.6%) and the cutting-loss was 45.6g(4.6%). 3. The average weight of total edible muscle from breast and leg was 51.5g(85.86% of breast and leg cut weight) and the percentages based on the carcass and live weights were 51.6% and 32.7%, respectively. 4. The contents of H$_2$O, protein, fat and water-protein ratio of breast muscle were 72.95%, 20.54%, 1.59% and 3.55, respectively and those of leg muscle were 71.9%, 19.12%, 3.96% and 3.76%, respectively. 5. The salt-soluble protein contents of breast and leg muscle were 7.97% and 6.26% and their concentrations based on the total protein content were 38.8% and 32.74%, respectively. 6. The emulsifying capacity of breast and leg muscle was 43.23$m\ell$and 43.23$m\ell$, respectively. 7. The W. H. C- of breast and leg muscle was 54.23% and 52.61%, respectively.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.239-244
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• 2008

To evaluate the acidity and chemical characteristics of rainwater in Korea, its pH and ion concentrations were investigated in Suwon from April to December, 2006. In addition, to estimate the contribution of ions on its acidity, ion composition and neutralization effect of major cations were investigated. Ion balance and electrical conductivity balance between measured and estimated values showed a high correlation. The mean pH and EC in rainwater collected during the investigation periods were 4.7 and $17.6{\mu}S\;cm^{-1}$, respectively. The monthly variation in EC showed a clear seasonal pattern, which had the lowest value of $9.1{\mu}S\;cm^{-1}$ in July and increased remarkably in November. $Na^+$ was the most abundant cation and followed by $NH_4{^+}>Ca^{2+}>H^+>Mg^{2+}>K^+$. Among them, $Na^+$ and $NH_4{^+}$ accounted for more than 65% of the total cations. In case of anions, the relative abundance was $SO_4{^{2-}}>NO_3{^-}>Cl^-$. About 67% of the total anions in rainwater was $SO_4{^{2-}}$, which showed $119.0{\mu}eq\;L^{-1}$ as mean value during the monitoring periods. Furthermore, 94% of the soluble sulfate in rainwater was identified as nss-$SO_4{^{2-}}$(non-sea salt sulfate). We also found that $NH_4{^+}$ and $Ca^{2+}$ contributed greatly in neutralizing the rain acidity, especially in dry season.

• Journal of Bio-Environment Control
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• v.27 no.1
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• pp.94-101
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• 2018

Mugwort (Artemisia princeps) is a medicinal plant that has a substance called euphatilin, which is effective for cell damage and gastritis recovery. The objectives of this study were to investigate the annual growth characteristics of Artemisia princeps in greenhouse and to increase the eupatiline content by environmental stresses. Growth and eupatilin content of the plants were compared after 6 weeks of seedling and subsequent 8 weeks of greenhouse cultivation. Photosynthesis of mugwort plants did not saturate even at a relatively high light intensity of $1,200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Growth rate of the plants reached its highest at two weeks after transplanting and began to decrease since 8 weeks after transplanting. The plants showed typical characteristics of a perennial herbaceous plant as they were sensitive to seasonal changes. In particular, the plants showed high growth and eupatilin content in spring and summer as vegetative growth periods, but flowering and wintering caused considerable decreases in growth and eupatilin content in fall and winter. Therefore, application of night interruption is essential for year-round cultivationof the plant. Two stresses and a elicitor were treated: drought stresses by stopping irrigation at 5, 6, 7, and 8 days before harvest; salt stresses with nutrient solution concentrations of 2, 4, 6, 8, and $10dS{\cdot}m^{-1}$ by adding sodium chloride at 3 days before harvest; and foliar applications of methyl jasmonates of 12.5, 25, 50, and $100{\mu}M$ at 3 days before harvest. Significant increase in eupatilin content was observed at drought stresses of 7- and 8-days of irrigation stop and foliar application of $25{\mu}M$ methyl jasmonate, while no significant increase observed at salt stresses. From the results, it was confirmed that the environmental treatments can improve the productivity and quality of Artemisia princeps as a phamaceutical raw material.

• Journal of the Mineralogical Society of Korea
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• v.25 no.4
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• pp.197-210
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• 2012

Hematite has been known to be the most stable form of various iron (oxyhydr)oxides in the surface environments. In this study, its properties as an adsorbent were examined and also adsorption of arsenic onto hematite was characterized as well. The specific surface area of hematite synthesized in our laboratory appeared to be $31.8g\;m^2/g$ and its point of zero salt effect, (PZSE) determined by potentiometric titration was observed 8.5. These features of hematite may contribute to high capacity of arsenic adsorption. From several adsorption experiments undertaken at the identical solution concentrations over pH 2~12, the adsorption of As(III) (arsenite) was greater than that of As(V) (arsenate). As of pH-dependent adsorption patterns, in addition, arsenite adsorption gradually increased until pH 9.2 and then sharply decreased with pH, whereas adsorption of arsenate was greatest at pH 2.0 and steadily decreased with the increasing pH from 2 to 12. The characteristics of these pH-dependent adsorption patterns might be caused by combined effects of the variation in the chemical speciation of arsenic and the surface charge of hematite. The experimental results on adsorption kinetics show that adsorption of both arsenic species onto hematite approached equilibrium within 20 h. Additionally, the pseudo-second-order model was evaluated to be the best fit for the adsorption kinetics of arsenic onto hematite, regardless of arsenic species, and the rate constant of As(V) adsorption was investigated to be larger than that of As(III).

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.6
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• pp.29-36
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• 2008

This study examined the de-icing agents' stresses on Pinus strobus and Pinus thunbergii by chlorophyll fluorescence analysis. The assumption of this study was that photosynthetic efficiency was changed by de-icing agents applied onto highways in winter by altering the concentration of the de-icier, types of de-icer and leaf surface coating liquid application. The practical purpose of this study was to investigate the de-icing gents stresses on Pinus strobus by the highway area where de-icing agents were used frequently and to discover out minimizing stratages to prevent further damages. or this simulation study, a sample plot was established in Bogae-myeon, Anseong, Gyeonggi-do and Pinus strobus and Pinus thunbergii were planted for the examination in April, 2005. Five types of de-icing agents - NaCl, $CaCl_2$, T product(NS40:low cWoride de-icer type), NaCl+$CaCl_2$ and T product+$CaCl_2$ - were selected and the their concentration was altered to 0%, 5%, and 9%. Five types of de-icing agents were applied to both trees treated by a leaf surface coating liquid and trees not treated by leaf surface coating liquid. For the fluorescence analysis, the leaf surface coating liquid, which was diluted by 10 times, was sprkinkled onto the two tree species three days prior to gathering samples. Sample leaves from the two tree species were gathered at 10 o'clock in the morning of mid-August, 2006 and brought to the laboratory within three hours to be dipped in different concentrations (0%, 5%, or 9%) of the five de-icing agents for two minutes. Then the eaves were placed on the filter paper dipped in each solution on a petri dish, sealed with polyethylene film and kept in a growth chamber at $22^{\circ}C$ for 72 hours. Out of the growth chamber, the leaves were treated with a chorophyll fluorescence reaction analyzer for 30 minutes to measure the initial light acceptance rate(Fo), maximum light acceptance ate(Fv/Fm), light acceptance usage(F' q/F' m) and optical electron delivery coefficient(qP). As a result, Pinus strobus' initial light acceptance rate(Fo) decreased as T product and NaCl increased in concentration, and $Cal_2$ did not reduce much with the eaf surface coating liquid application. Maximum light acceptance rate(Fv/Fm) and light acceptance usage(F' q/F' m) decreased sharply as T product and NaCl increased in concentration and NaCl+$CaCl_2$ and T product+$CaCl_2$ did not reduce much with leaf surface coating liquid application. Optical electrons delivery coefficient (qP) decreased as T product increased in concentration on trees without the leaf surface coating liquid application and all other de-icing agents did not show much reduction. As for Pinus thunbergii, the initial light acceptance rate(Fo) decreased as T product increased in concentration, but the maximum light acceptance rate(Fv/Fm) was not reduced much by changes in concentration. light acceptance usage(F' q/F' m) decreased as NaCl increased in concentration and optical electron delivery coefficient(qP) decreased as NaCl increased in concentration in both with and without leaf surface coating liquid application. In conclusion, it was possible to plant Pinus strobus if spraying leaf surface coating liquid or cleaning deicing salt to prevent the damage caused by deicing agents was more economical than replacing the trees. If not, it was better to plant Pinus thunbergii. Another way to decrease the deicing gents stresses of landscape plants would be planting the trees further away from the roads even though it might take longer period to display its planting functions.

• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.56-68
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• 1985

This study was conducted (1) to measure the nitrogen content of various parts of trees in a 24-year-old Pinus koraiensis plantation, providing a harvest method with the least impact on the self-serving mechanisms in the nitrogen status of the ecosystem and (2) to examine the seasonal changes in inorganic nitrogen (ammonium salt and nitrate, separately) at various soil depths and to study the self-serving mechanisms for nitrogen at the ecosystem, providing an appropriate method and season for the application of nitrogen fertilizers. The results obtained in this study were as follows; 1) Of the total nitrogen content of the total tree biomass (except for roots), nearly 61.5% was distributed in the needles, 20% in the branches, 5.5% in the stem bark, and 13% in the stem wood. Therefore, the harvest method of removing only wood parts for pulpwood production has little impact on the self-serving mechanisms of the site's nitrogen status. 2) Inorganic nitrogen concentrations decreased with increasing soil depths. The seasonal average concentration of inorganic nitrogen was highest in early spring and decreased in the following descending order; autumn, tollowed by mid-summer, and early summer. This pattern resulted from the fact that the loss of nitrate was greatly influenced by environmental factors. Thus, it was suggested that an application of active nitrogen fertilizer would be appropriate in spring.