• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.6
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• pp.303-308
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• 2017

The $FeCl_3$ waste solution used to etch various metals contains valuable metal such as nickel. In this study, we recovered as high purity nickel carbonate crystalline powders from nickel-containing etching waste solution after regeneration of iron chloride. Firstly we eliminated about of the iron impurities under the condition of pH 4 using 5 % NaOH aqueous solution and then removed the remaining impurities such as Ca, Mn and Zn etc. by using solvent extractant D2EHPA (Di-(2-ethylhexyl) phosphoric acid). Thereafter, nickel carbonate powder having a purity of 99.9 % or more was obtained through reaction with sodium carbonate in a nickel chloride solution.

• Economic and Environmental Geology
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• v.42 no.3
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• pp.217-234
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• 2009

This study characterized groundwater quality and the influence of agrochemicals in a part of Ilgwang-Myeon agricultural area in Gijang-Gun, Busan Metropolitan City, using factor analyses. From the 1st, 2nd, and 3rd analyses of groundwater samples, the mean concentrations of $Ca^{2+}$, $Na^+$, $Mg^{2+}$, $K^+$, $Zn^{2+}$, $Cu^{2+}$, $Fe^{2+}$, $Al^{3+}$, $NO_3\;^-$, $Cl^-$, $SO_4\;^{2-}$, $F^-$, and $SiO_2$ were higher in the 2nd analysis than the other analyses. Pesticide carbofuran and herbicide alachlor were detected at the wells more than a half of all the wells in the 2nd analysis but not in the 4th analysis. This fact may be explained by that a higher precipitation induced higher infiltration rate of contaminants into groundwater during the 2nd survey. According to R- and Q-mode factor analyses, and chemical composition, inorganic constituents excepting $SiO_2$, $HC0_3\;^-$-, and $F^-$ may be influenced by anthropogenic sources (manures, synthetic fertilizers, and domestic wastes), seawater as well as water-mineral interaction. A typical indicator of groundwater contamination, nitrate, exceeds around 4-5 times over the Korean standard for drinking water. Additionally, the influence of seawater diminishes from the seaside to inland.

• Journal of the Korean Chemical Society
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• v.48 no.6
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• pp.577-582
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• 2004

The azacrown compounds, 1,4-dioxa-7,10,13-triazacyclopentadecane-N,N',N''-triacetic acid, $N-ac_3[15]aneN_3O_2(II_a)$ and 1,4-dioxa-7,10,13-triazacyclopentadecane-N,N',N''-tripropioc acid, $N-pr_3[15]aneN_3O_2(II_b)$ were synthesized by modified methods. Potentiometry was used to determine the protonation constant of the $N-ac_3[15]aneN_3O_2\;and\;N-pr_3[15]aneN_3O_2$. The stability constants of complexes of the trivalent metal ions of $Ce^{3+},\;Eu^{3+},Gd^{3+},and\;Yb^{3+}$ and divalent metal ions of $Co^{2+},\;Ni^{2+},\;Cu^{2+},\;and\;Zn^{2+}$ with the ligands $N-ac_3[15]aneN_3O_2\;and\;N-pr_3[15]aneN_3O_2$ have been determined at $25{\pm}0.1^{\circ}C$ in 0.1 M $NaClO_4$ solution by potentiometric methods. The metal ion affinities of the two triazamacrocyclic ligands with three pendant acetate or propionate groups are compared to those obtained for the similar ligands, 1,7-dioxa-4,10,13-triazacyclopentadecane-N,N',N''-triacetic acid, and 1,7-dioxa-4,10,13- triazacyclopentadecane-N,N',N''-tripropioc acid. The trends in stability of complexes for different metal ions due to changes in the nitrogen position of the donor atoms of the ligand are discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.201-206
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• 1992

Pinus pollen is used as the chief ingredient for Song-wha-dashik (Korea's traditional pattern-pressed candy). It has been the food stuff indispensable especially on the occasion of performing ancestral rites and holding a banquet since Shilla and Koryo Dynasty. In this paper, therefore, a new examination is made of the nutritive ingredients of the very Pinus pollen. Analysis has been made of the proximate composition, minerals, heavy metals, vitamins and free sugars of the Pollen of both Pinus densinora Siebol et Zuccarini and Pinus rigida Miller. In the proximate composition, Pinus rigida Miller is high except in free sugar ; crude ash (4.0%), crude protein (15.0%), crude fat (2.5%), crude fiber (17.5%). A lot of minerals have been found in both the samples. They contain Mg, Cl, Ca, Fe, Mn, Na, Zn, etc. In heavy metals, both the samples contain the same quantity of Cd(0.3 ppm) and the contents of Pb, Cu, and As are lower than the maximal limit permitted for food stuff. The contents of vitamin B$_1$, B$_2$, vitamin C are a little higher in Pinus rigida Miller : in vitamin E, on the contrary, Pinus densiflora Siebol et Zucarini (1.6 mg) doubles Pinus rigida Miller (0.8 mg). In free sugars, the results is as follows : 6.6%/6.9% in sucrose : 0.2% in fructose : 2.1% /2.9% in glucose respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.231-237
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• 2006

The extracellular enzyme alginase produced by Bacillus licheniformis AL-577 was purified by ion chromatography on CM-Cellulose column, DEAE-Sepharose column, and followed by gel filtration on Sephadx G-100 column. The optimum pH and temperature for the activity of the purified enzyme were 6.0 and $35^{\circ}C$, respectively. The enzyme was stable at the pH range of $6.0\~9.0$ and at $20^{\circ}C$. The molecular weight of the enzyme was estimated to be about 25,500 daltons by SDS-polyacrylamide gel electrophoresis. NaCl was required for high activity of the enzyme. The enzyme was inhibited by $Ba^{2+},\;Co^{2+},\;Cu^{2+},\;Fe^{2+},\;Mg^{2+},\;Zn^{2+},\;NH_4^+$, EDTA, L-cysteine, and 2-mercaptoethanol, while stimulated by DTT, O-phenanthroline, $K^+$ and $Li^+$. This enzyme was proposed to be an alginase specifically degrading alginic acid.

• Journal of Ecology and Environment
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• v.29 no.2
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• pp.157-163
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• 2006

Growth of G. max treated with $NO_3^-$-N was decreased by high NaCl treatments, but $NH_4NO_3$-fed plants showed good growth with enhanced activity of antioxidative enzymes (SOD and APX). Especially, activity of APX was higher in 5 mM $NH_4NO_3$-fed plants than other types of N-supplied plants throughout the stress period. Higher SOD activity under salt stress was accompanied by increase in APX activity in 5 mM $NH_4NO_3$-fed plants. Similarly, application of calcium confirmed somewhat positive effects on growth. Salt-treated soybean plants showed the best growth response with the increase of SOD and APX activity at an additional 5 mM calcium treatment. Especially, the increase of SOD activity through the strengthened CuZn-SOD isoform was remarkable.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.1
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• pp.23-32
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• 1999

Deposition is one of the important removal mechanisms for the ambient aerosol, and it also leads to adverse environmental and economic impacts. The purpose of this study was to investigate chemical compositions and spatial distributions of fall-out aerosols. A total number of 340 samples were collected at 35 sampling sites in Suwon area from January to November, 1996. Twelve inorganic elements (Al, Ba, Cd, Cr, K, Pb, Sb, Zn, Cu, Fe, Ni, and V) and eight ionic components ($F^-$, Cl, $NO_3^-$, $SO_4^{2-}$, $Na^+$, $NH_4^+$, $Mg^{2+}$, and $Ca^{2+}$) were analyzed by AAS and IC, respectively. The monthly variation showed that the flux of fall-out particles was increased in the spring season(March, April, and May) and decreased from August to October. Arithmetic mean flux of fall-out particles was 176.8 kg/$ extrm{km}^2$/day during the study period. The fluxes of each chemical species were $SO_4^{2-}$ 12.414, $Ca^{2+}$ 7.369, $NO_3^-$ 5.812, $Cl^-$ 3.566, $NH_4^+$ 3.176, Fe 3.107 kg/$\textrm{km}^2$/day, and so on. By using a kriging analysis, spatial distribution pattern of those fluxes was intensively studied. Total fluxes estimated in Suwon city were 8424.72t/y of fall-out particles, 519.27t/y of $SO_4^{2-}$, 336.79t/y of $Ca^{2+}$,267.34 t/y of $NO_3^+$, 155.36t/y of $Cl^-$, 147.79t/y of Fe.

• Animal Bioscience
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• v.36 no.8
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• pp.1285-1292
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• 2023

Objective: The objective of this study was to develop a novel endolysin (PanLys.1) for the specific killing of the ruminal hyper-ammonia-producing bacterium Peptostreptococcus anaerobius (P. anaerobius). Methods: Whole genome sequences of P. anaerobius strains and related bacteriophages were collected from the National Center for Biotechnology Information database, and the candidate gene for PanLys.1 was isolated based on amino acid sequences and conserved domain database (CDD) analysis. The gene was overexpressed using a pET system in Escherichia coli BL21 (DE3). The lytic activity of PanLys.1 was evaluated under various conditions (dosage, pH, temperature, NaCl, and metal ions) to determine the optimal lytic activity conditions. Finally, the killing activity of PanLys.1 against P. anaerobius was confirmed using an in vitro rumen fermentation system. Results: CDD analysis showed that PanLys.1 has a modular design with a catalytic domain, amidase-2, at the N-terminal, and a cell wall binding domain, from the CW-7 superfamily, at the C-terminal. The lytic activity of PanLys.1 against P. anaerobius was the highest at pH 8.0 (p<0.05) and was maintained at 37℃ to 45℃, and 0 to 250 mM NaCl. The activity of PanLys.1 significantly decreased (p<0.05) after Mn²⁺ or Zn²⁺ treatment. The relative abundance of P. anaerobius did not decrease after administration PanLys.1 under in vitro rumen conditions. Conclusion: The application of PanLys.1 to modulate P. anaerobius in the rumen might not be feasible because its lytic activity was not observed in in vitro rumen system.

• Applied Microscopy
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• v.32 no.4
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• pp.399-410
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• 2002

This study was performed to investigate the effects of Bambusae Caulis in Liquamen (bamboo extract) on the changes of antioxidant enzymes and histopathological changes of liver and kidney in mice when administered in different dosages. The experimental groups were divided into four. For control group, 0.9％ NaCl (0.2 ml/25 g B.W.) and for experimental groups, 5% (H1 group), 10% (H2 group), and 20%(H3 group) bamboo extract diluted with 0.9％ NaCl, were administered (0.2 ml/25 g B.W.) respectively for 28 days at an interval of 48 hours. MnSOD activities were increased in H1 group (46%, P<0.05), H2 group (40%, P<0.05), and H3 group (34%, P<0.05) as compared to the control group. CuZnSOD activities were increased in H1 group (11%, P<0.05), but were decreased in H3 group (13%, P<0.05). The activities of catalase were decreased in H1 group (39%, P<0.05), H2 group (34%, P<0.05), and H3 group (31%, P<0.05) as compared to the control group. Histopathological observation revealed ballooned hepatocytes in the pericentral and periportal veins of H1 group. More ballooned and injured hepatocytes than in H1 group were observed in the H2 and H3 groups. Detachment of endothelial cells of the central vein was observed in the H2 and H3 groups. These results indicated that bamboo extract developed dose-dependent changes in antioxidant enzyme activities and developed histopathological changes of liver and kidney.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.2
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• pp.55-62
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• 2021

This study aims to reduce the rancid odor generated during the fermentation process of kimchi by inserting zinc oxide (ZnO) into an inorganic porous material with a high surface area to decompose or adsorb the fermentation odor. ZnO activated by the presence of moisture exhibits decomposition of rancid odors. Mixed with Titanium dioxide (TiO₂), a photocatalyst. To manufacture the packaging liner used in this study, NaOH, ZnCl₂, and TiO₂ powder were placed in a tank with diatomite and water. The sludge obtained via a hydrothermal ultrasonication synthesis was sintered in an oven. After being pin-milled and melt-blended, the powders were mixed with linear low-density polyethylene (L-LDPE) to make a masterbatch (M/B), which was further used to manufacture liners. A gas detector (GasTiger 2000) was used to investigate the total amount of sulfur compounds during fermentation and determine the reduction rate of the odor-causing compounds. The packaging liner cross-section and surface were investigated using a scanning electron microscope-energy dispersive X-ray spectrometer (SEM-EDS) to observe the adsorption of sulfur compounds. A variety of sulfur compounds associated with the perceived unpleasant odor of kimchi were analyzed using gas chromatography-mass spectrometry (GC-MS). For the analyses, kimchi was homogenized at room temperature and divided into several sample dishes. The performance of the liner was evaluated by comparing the total area of the GC-MS signals of major off-flavor sulfur compounds during the five days of fermentation at 20℃. As a result, Nano-grade inorganic compound liners reduced the sulfur content by 67 % on average, compared to ordinary polyethylene (PE) foam liners. Afterwards SEM-EDS was used to analyze the sulfur content adsorbed by the liners. The findings of this study strongly suggest that decomposition and adsorption of the odor-generating compounds occur more effectively in the newly-developed inorganic nanocomposite liners.