• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.247-247
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• 2023

Coastal lagoons play a crucial role in water exchange, water quality, and biodiversity. It is essential to monitor and understand the dynamics of hydrogeochemistry in lagoon water and its groundwater to preserve and sustainably manage the groundwater-dependent ecosystems like coastal lagoons. This study investigated the spatial and temporal hydrogeochemical characteristics of coastal lagoon (Songjiho) and groundwater on the east coast of Korea. The concentrations of major ions, water isotopes, and nutrients (nitrogen and dissolved organic carbon) in lagoon water and groundwater were periodically monitored for one year. The study revealed that major ions and total dissolved solids (TDS) concentration were higher at deeper depths of aquifers and closer to the coastal area. The hydrogeochemical characteristics of coastal lagoon and groundwater chemistry were classified into two types, Ca-Mg-HCO₃ and Na-Cl, based on their spatial location from inland to coastal area. Moreover, the hydrogeochemical characteristics of coastal lagoons and groundwater varied significantly depending on the season. During the wet season, the increased precipitation and evaporation lead to changes in water chemistry. As a result, the total organic carbon (TOC) of coastal lagoons increases during this season, likely due to increased runoff by rainfall whereas the variation of chemical compositions in the lagoon and groundwater were not significant because there is reduced precipitation, resulting in stable water levels and during the dry season. The study emphasizes the impact of spatial distribution and seasonal changes in precipitation, evaporation, and river discharge on the hydrogeochemical characteristics of the coastal aquifer and lagoon system. Understanding these impacts is crucial for managing and protecting coastal lagoons and groundwater resources.

• Korean Journal of Materials Research
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• v.12 no.11
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• pp.860-864
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• 2002

$Li^{+}$ extraction reactions with ion-exchange type lithium manganese oxide in an aqueous phase were examined using chemical and x-ray diffraction (XRD) analysis. In the process of extraction reaction, the lithium manganese oxide showed a topotactic extraction of $Li^{+ }$ in the aqueous phase mainly through an ion-exchange mechanism, and the $Li^{+}$ extracted samples indicated a high selectivity and a large capacity for $Li^{+}$ . The electronic structures and chemical bonding properties were also studied using a discrete variational (DV)-X$\alpha$ molecular orbital method with cluster model of (Li$Mn_{12}$ $O_{40}$ )$^{27-}$ for tetrahedral sites and ($Li_{7}$ Mn $O_{38}$ )$^{3}$ for octahedral site in $Li_{1.33}$ $Mn_{1.67}$ / $O_{4}$ respectively. Li in the manganese oxides is highly ionized in both sites, but the net charge of Li was greater for tetrahedral sites than octahedral. These calculations suggest that the tetrahedral sites have higher $Li^{+}$ $H^{+}$ exchangeability than the octahedral sites, and are preferable for the selective adsorption for L $i^{+}$ ions.s.

• Economic and Environmental Geology
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• v.45 no.3
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• pp.265-276
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• 2012

Current study includes the analysis of mine tailings and leachate water and prediction of species originated from the tailings. The variation of contaminants were measured upon the distance from the tailings to the nearby stream. The ions concentration was highest at the tailings and pit mouth and it becomes lower as it goes far away from the origin. This is the reason that the leachate was diluted with the uncontaminated stream water. The tailings were mainly classified into reddish one and yellow one. The main mineral of reddish tailings were quarts, illite, plumbojarosite and a small amount of sphalerite. The main mineral of yellow tailings were muscovite, quarts, plumbojarosite, and a small amount of chalcopyrite and sphalerite. Pb and Zn were found in the leachate in high concentration and become the major contaminants. These come from the dissolution of plumbojarosite and sphalerite contained in the mine tailings.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.391-397
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• 2014

Acid mine drainage occurrence is a serious environmental problem by mining industry; it usually contain high levels of metal ions, such as iron, copper, zinc, aluminum, and manganese, as well as metalloids of which arsenic is generally of greatest concern. It causes mine impacted soil pollution with mining and smelting activities, fossil fuel combustion, and waste disposal. In the present study, three bacterial strains capable of producing urease were isolated by selective enrichment of heavy metal contaminated soils from a minei-mpacted area. All isolated bacterial strains were identified Sporosarcina pasteurii with more than 98% of similarity, therefore they were named Sporosarcina sp. KM-01, KM-07, and KM-12. The heavy metals detected from the collected mine soils containing bacterial isolates as Mn ($170.50mg\;kg^{-1}$), As ($114.05mg\;kg^{-1}$), Zn ($92.07mg\;kg^{-1}$), Cu ($62.44mg\;kg^{-1}$), and Pb ($40.29mg\;kg^{-1}$). The KM-01, KM-07, and KM-12 strains were shown to be able to precipitate calcium carbonate using urea as a energy source that was amended with calcium chloride. SEM-EDS analyses showed that calcium carbonate was successfully produced and increased with time. To confirm the calcium carbonate precipitation ability, urease activity and precipitate weight were also measured and compared. These results demonstrate that all isolated bacterial strains could potentially be used in the bioremediation of acidic soil contaminated by heavy metals by mining activity.

• Journal of the Mineralogical Society of Korea
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• v.5 no.2
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• pp.93-101
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• 1992

Several "Napseok" mines are distribute in the Miryang area where the volcanic rocks are hydrothermally altered. The "Napseok" are pyrophyllite and dickite, with a small amount of silicates such as quartz, illite, tosudite and dumortierite. Other associated minerals are oxides, hydroxides, sulfides, sulfates and phosphates. Pyrophyllite which occurs as 2M polytype exhibits that the basal spacing increases due to dehydroxylation at 750${\circ}C$. Halloysite shows tubular forms. Wavellite is precipitated in fissures during the latest stage of the hydrothermal alteration process. Five mineral zones, that is pyrophyllite-deckite, illite, halloysite, silica, and albite-chlorite zones, are recognized with decreasing alteration degree. Clay minerals were formed by leaching of Si and alkali ions fron the country rocks, considering mineral assemblages, pyrophyllite polytype and thermodynamical data reported in the literature, temperatures of formation of main clay deposits are assumed to be 270 to 350${\circ}C$.

• Asian Journal of Atmospheric Environment
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• v.3 no.1
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• pp.27-41
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• 2009

Internally mixed states of submicron particles during transport from the Asian continent to the Pacific Ocean were analyzed using a single-particle time-offlight mass spectrometer. The observation was conducted at Tsukuba in Japan in the spring of 2005 in order to investigate springtime transport of particles from the continent. The sum of ion intensities of sulfate (${HSO_4}^-$) detected in particles originating from the continental air masses counted for 75% of that in all particles during the observation. By analyzing correlations among compounds, origins and internally mixed states of compounds were estimated. It was found that nitrate was mixed with sulfate-rich particles as the air mass approached Japan. It was confirmed that Asian mineral dust particles played significant roles for transport of continental sulfate to Japan. As a result of analysis on internal mixing of chlorine and nitrate, it was implied that the chlorine loss in fine sea salt particles had already proceeded at Tsukuba. It was characteristic that fluoride ions were significantly detected, coal combustion in the Asian Continent can be an important source of fluorides detected in Japan through the westward transportation of fine particles including fluorides.

• Animal cells and systems
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• v.2 no.4
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• pp.455-462
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• 1998

A survey was conducted on the inorganic and organic solute patterns of plants in connection with nitrate metabolism according to different light regimes (1.9, 16.0, 91.5 $Wm^{-2}$). Besides measuring in vivo NRA, we also quantitatively analyzed ater-soluble inorganic ions, organic acids, low molecular weight carbohydrates, amino aciss and total N (% DW). Among 4 Carex species, C. pilosa is known as shade-adapted species and the others as half (C. gracilis) to full (C. rostrata & C. distans) light-adapted species. Compared to species adapted to high light intensity, shade-adapted C. pilosa showed reduced productivity under the highest light intensity. In general, nitrate and amino acid levels decreased at higher light intensity, while sugar and organic acid concentrations increased. In C. pilosa osmolality tended to rise with increasing light intensity, while in the other species it tended to fall. Under low light intensity, the drop in soluble carbohydrate contents is osmotically compensated for by an enhanced nitrate concentration. It is concluded that competition between nitrate and $CO_2$reduction for reductants and ATP from photosynthesis may have important ecological consequences for the adaptation of plants to low or high light conditions. Additionally, the patterns of ionic changes due to increased light intensities were essentially the same in all selected species, indicating similar characteristics of heir mineral ion and organic acid metabolism as well as in field-grown Carex species.

• Journal of Plant Biotechnology
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• v.47 no.3
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• pp.248-253
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• 2020

Moringa (Moringa oleifera), which is native to tropical and subtropical climates, now grows in Korea due to its warming climate. Since it is also imported and used for food and other products in various countries, it is necessary to analyze the properties of moringa being imported into Korea. In this study, the antioxidant activity and total phenol and flavonoid content were high in the leaves and twigs and showed a positive correlation. The mineral content was also high in the leaves and twigs, and potassium ions were the most abundant mineral. In addition, seven phenolic acids (caffeic acid, chlorogenic acid, cinnamic acid, coumaric acid, ferulic acid, gallic acid, and syringic acid) and four flavonoids (kaempferol, myricetin, quercetin, and rutin) were detected in the leaves, twigs, and stems, and the ferulic acid and quercetin content was particularly high. The results of this study can be used as comparative data for domestic moringa growers in the future.

• Journal of the Mineralogical Society of Korea
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• v.17 no.2
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• pp.123-133
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• 2004

Carbonate minerals are examined by cathodoluminescence microscopy and chemical analysis to characterize the carbonate materials occurring in the Tertiary marine basin. The microscopic technique with cathodoluminescence gives new informations that are not obtainable by conventional microscopic techniques. The carbonate cements in sandstones appear to be uniform with transmitted light or with crossed prisms. but the inspection with cathololuminescence reveals foraminiferal tests and rhomb crystals in the carbonate cements. The chemical analysis indicates that the intense luminescence depends mainly on the presence of$ Mn^{ 2+}$ and $Fe^{2+}$ as activator ions, but the $Fe^{2+}$ also acts as an important quencher ion when Fe concentration in dolomite is over 10,000 ppm. The dolomites, which are rich in calcium, are formed at the early stage of diagenesis at a temperature of about 60 ～ $70^{\circ}C$.

• Journal of the Mineralogical Society of Korea
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• v.12 no.2
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• pp.55-65
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• 1999

Spotted cordierite occurs as the result of intrusion of Wolaksan Granite of Cretaceous age in the northern part of the Ogcheon Metamorphic Belt, forming a contact metamorphic zoning in accordance with the distance from the granite body: a cordierite-muscovite-biotite-quartz assemblage and the higher-temperature cordierite-biotite-quartz-(cummingtonite). These quartz-ubiquitous mineral assemblages identified in the cordierite spot seem to reflect Al-deficient condition of the protolith. TEM observations of textural relations between the cordierite and mica within the cordierite spot clearly reflect that cordierite was formed at the expense of micaceous matrix. A structure refinement of the poikiloblastic cordierite was performed by the Rietveld refinement method. Unit cell of the cordierite was determined to be as follows : lower-temperature type: a=17.1480(9)${\AA}$, b=9.7743(6)${\AA}$, c=9.3184(5)${\AA}$, V=1561.9(4)${\AA}$3, higher-temperature type: a=17.136(2)${\AA}$, b=9.751(1)${\AA}$, c=9.322(1)${\AA}$, V=1557.7(4)${\AA}$3. They show a remarkable difference in the unit cell dimension. The refinement results indicate that structural sites of lower-temperature cordierite are wholly occupied by appropriating ions. Compared to this, tetrahedral sites of the higher-temperature type exhibit an order/disorder ranging about 5-8% as the result of substitution between Si4+ and Al3+, except for T26 site occupied wholly by Al3+. These structural differences seem to be related to the formation temperatures of both cordierite types.