• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.685-687
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• 1994

• Journal of the Korean Magnetic Resonance Society
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• v.1 no.1
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• pp.1-6
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• 1997

Several dioxovanadate (V) complexes are synthesized and studied by solution and solid-state 51V NMR spectroscopy. In the results, large 51V chemical shift anisotropy ({{{{ DELTA delta }}a = -800 ∼720 ppm) and quadrupole coupling (e2q /h = 7.50 ∼ 9.16 MHz) were observed in the solid-state complexes. The isotropic chemical shifts of the solid samples are very close to the values obtained from solution measurements.

• Journal of Environmental Health Sciences
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• v.48 no.2
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• pp.66-74
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• 2022

Background: The health effects of particulate matter (PM_2.5) bonded with various harmful chemicals differ based on their composition, so investigating and managing their concentrations and composition is vital for long-term management. As industrial complexes emit considerable quantities of pollutants, higher PM_2.5 concentrations and chemical component effects are expected than in other places. Objectives: We investigated the concentration distribution ratios of PM_2.5 chemical components to provide basic data to inform future major emissions control and PM_2.5 reduction measures in industrial complexes. Methods: We monitored five sites near the Ansan and Siheung industrial complexes from August 2020 to July 2021. Samples were collected and analyzed twice per week in spring/winter and once per week in summer/autumn according to the National Institute of Environmental Research in the Ministry of Environments' Air Pollution Monitoring Network Installation and Operation Guidelines. We investigated and compared composition ratios of 29 ions, carbon, and elemental components in PM_2.5. Results: The analysis of PM_2.5 components at the five sites revealed that ion components accounted for the greatest total mass at approximately 50% while carbon components and elemental components contributed 23~28% and 8~10%, respectively. Among the ionic components, NO₃^- occupies the greatest proportion. OC occupies the greatest proportion of the carbon components and sulphur occupies the greatest proportion of elemental components. Conclusions: This study investigated the concentration distribution ratios of PM_2.5 chemical components in industrial complexes. We believe these results provide basic chemical component concentration ratio data for establishing future air management policies and plans for the Ansan and Siheung industrial complexes.

• Applied Chemistry for Engineering
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• v.32 no.2
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• pp.180-189
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• 2021

N-Heteroaryl carbazoles were synthesized with thermal heating in the presence of Cu(I) catalyst and used as main ligands for the preparation of heteroleptic Ir(III) complexes. In these Ir(III) complexes, 6-membered ring structures of Ir-ligand chelation were found by single crystal X-ray diffraction. The blue shift of photoluminescence for Ir(III) complexes was observed in the case of the strong bond formation between Ir and ancillary ligands. It also has been clearly shown that the higher electron density of heteroaryl aromatic ring influenced shorter maximum photoluminescence wavelength (λmax) of Ir(III) complexes. Since the new Ir(III) complexes showed good phosphorescent emission, they could be potentially used as OLED materials in the emission Layer.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.690-692
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• 1994

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.557-561
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• 1993

The interaction of vanadium(V) with various a-hydroxycarboxylate ligands in aqueous solution at pH 3.2 have been studied by $^{51}V$ and $^{13}C$ NMR spectroscopies. From the results it is supposed that vanadates mainly form the octahedral complexes with lactate, 2-hydroxybutyrate, glycerate, and malate. While, vanadates form the trigonal-bipyramidal complexes with glycolate, tartarate, and 2-hydroxy-3-methylbutyrate, and tetrahedral complexes with pyruvate(diol), 2-hydroxyisobutyrate, and 2-hydroxy-3-methylbutyrate. The bipyramidal products are formed as monomeric compounds. The octahedral products are formed as dimeric compounds with no evidence for a significant proportion of the monomeric derivatives. The complexes are mainly formed through the coordination at the carboxylate and the 2-hydroxyl groups of the ligands.

• Bulletin of the Korean Chemical Society
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• v.12 no.3
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• pp.243-244
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• 1991

• Korean Journal of Veterinary Research
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• v.49 no.3
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• pp.257-263
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• 2009

Bovine mastitis is an important disease causing serious economic loss in dairy production and food poison in public health. Escherichia coli and Staphylococcus aureus are the major causative agents of bovine mastitis. These bacteria were found in milk and environmental condition such as feces, water, soil and so on. Bovine mastitis causative micro-organisms can survive in 1-2 weeks in feces and bed complexes. Low level of percentage of water content (PWC) of feces and bed complexes can reduce the spreading of bovine mastitis incidence from environmental contamination. In this study, we developed the fecal dehydrating system and determined the elimination rates of bovine mastitis causative agent from feces and bed complexes. To develop the fecal dehydrating system, the screw pressurized dehydrating system was used and the maximum rate of dehydrating was reached to 52% PWC using 90% PWC (wet base) of fecal and bed complexes. The elimination rates of the dehydrating system for E. coli and S. aureus were reached at 41.19 $\pm$ 7.84% to 62.55 $\pm$ 8.71% in various percentages of PWC of feces and bed complexes (80, 85 and 90%). These results suggested that the application of fecal dehydrating system would reduce the exposure of dairy cattle to bovine mastitis causing agents contaminated feces and bed complexes, and can be used for environmental bovine mastitis control avoiding misuse or abuse of chemical disinfectants and antibiotics in dairy farm.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.3
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• pp.184-191
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• 2004

Forest soils were collected from various sites adjacent to the heavy industrial complexes and soil solutions were extracted to characterize the chemical properties and to find factors affecting forest decline by acid deposition. Concentrations of $NO_3{^-}$, $SO{_4}^{2-}$, $F^-$ and Al in the soil solutions collected from industrial complexes were 2-33 times higher than those from the non-industrial areas. pH and Al concentrations were significantly correlated with $NO_3{^-}$ and $SO{_4}^{2-}$ concentrations. Forest soils from Onsan and Ulsan regions had very low Ca and Mg concentrations in the soil solutions. In these sites, the molar ratios of Ca/Al and Mg/Al were also lower than 2 and 1, respectively. Aluminum concentrations in the A and B horizons were 547 and $683mg\;kg^{-1}$, respectively, which were considered to be high enough to inhibit tree growth. Magnesium deficiency in A horizon and high concentrations of Al and Mn in B horizon were considered as the major limiting factors for tree growth by inhibiting the uptake of Ca and Mg and causing the imbalance of nutrients in both soil solution and trees.

• Journal of the Korean Chemical Society
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• v.35 no.6
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• pp.667-672
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• 1991

Two palladium(Ⅱ) complexes, N-(2-aminoethylisonitrosobenzoylacetone imino) chloropalladium(Ⅱ), PdCl(IBA)-en, and N-(3-aminopropylisonitrosobenzoylacetone imino) chloropalladium(Ⅱ), PdCl (IBA)-tn, have been prepared from the condensation of isonitrosobenzoylacetone (IBA) and diamine (ethylenediamine(en) or trimethylenediamine(tn)) in the presence of palladium(Ⅱ) ion. It is suggested that the Schiff base formed by condensation of an isonitrosobenzoylacetone and a diamine coordinates to the metal through three nitrogens of isonitroso (=N-O), C=N, and $NH_2$groups as a tridentate ligand. And also a chloride ion coordinates to the metal in addition to the Schiff base ligand to form a square-planar geometry.