• Journal of the Korean Chemical Society
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• v.65 no.4
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• pp.249-253
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• 2021

Litter and manure were obtained at a cow house of a livestock farm in Andondg city. We examined the change of formation of nitrogen and phosphorous from these samples and tried to suggest a more useful and realistic way for removing them. Constituent and its content of sample were identified by XRF. NO₂^-, NO₃^-, and PO₄^3- ions and NH₄⁺, T-P and T-N released from sample were analyzed using ion chromatograph and UV/Vis spectrometry, respectively. As the results of this study, the ammonia nitrogen in the early stage of cow excretion is a need to make an ammonia gas state that can be immediately volatile by increasing the pH. Nitrogen and phosphorous, the main source of nutrition in green algal bloom can be removed by transforming insoluble salts such as calcium phosphate (CaHPO₄·3H₂O) and struvite (NH₄MgPO₄·6H₂O), respectively, with addition of Ca and Mg after stimulating fermentation of manure.

• Membrane Journal
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• v.32 no.5
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• pp.348-356
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• 2022

With the development of the bio industry, membrane chromatography with a high adsorption efficiency is emerging to replace the existing column chromatography used in the downstream processes of pharmaceuticals, food, etc. In this study, through the deacetylation reaction of two commercial cellulose acetate (CA) membranes with different pore sizes, the porous regenerated cellulose (RC) supports for membrane chromatography were obtained to attach the anion exchange ligands. The adsorptive membranes for anion exchange were prepared by attaching an anion exchange ligand ([3-(methacryloylamino) propyl] trimethylammonium chloride) containing quaternary ammonium groups on the RC supports by grafting and UV polymerization. The protein adsorption capacities of the prepared membranes were obtained through both the static binding capacity (SBC) and the dynamic adsorption capacity (DBC) measurement. As a result, the membrane chromatography with the smaller the pore size, the larger the surface area showed the highest protein adsorption capacity. Membrane chromatography which was prepared by using deacetylated commercial CA support with MAPTAC ligand (i.e., RC 0.8 + MAPTAC: 43.69 mg/ml, RC 3.0 + MAPTAC: 36.33 mg/ml) showed a higher adsorption capacity compared to commercial membrane chromatography (28.38 mg/ml).

• Restorative Dentistry and Endodontics
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• v.45 no.4
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• pp.54.1-54.16
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• 2020

Objectives: This study aimed to synthesize nanocrystals (NCs) of zinc oxide (ZnO) and calcium ion (Ca²⁺)-doped ZnO with different percentages of calcium oxide (CaO), to evaluate cytotoxicity and to assess the effects of the most promising NCs on cytotoxicity depending on lipopolysaccharide (LPS) stimulation. Materials and Methods: Nanomaterials were synthesized (ZnO and ZnO:xCa, x = 0.7; 1.0; 5.0; 9.0) and characterized using X-ray diffractometry, scanning electron microscopy, and methylene blue degradation. SAOS-2 and RAW 264.7 were treated with NCs, and evaluated for viability using the MTT assay. NCs with lower cytotoxicity were maintained in contact with LPS-stimulated (+LPS) and nonstimulated (-LPS) human dental pulp cells (hDPCs). Cell viability, nitric oxide (NO), and reactive oxygen species (ROS) production were evaluated. Cells kept in culture medium or LPS served as negative and positive controls, respectively. One-way analysis of variance and the Dunnett test (α = 0.05) were used for statistical testing. Results: ZnO:0.7Ca and ZnO:1.0Ca at 10 ㎍/mL were not cytotoxic to SAOS-2 and RAW 264.7. +LPS and -LPS hDPCs treated with ZnO, ZnO:0.7Ca, and ZnO:1.0Ca presented similar NO production to negative control (p > 0.05) and lower production compared to positive control (p < 0.05). All NCs showed reduced ROS production compared with the positive control group both in +LPS and -LPS cells (p < 0.05). Conclusions: NCs were successfully synthesized. ZnO, ZnO:0.7Ca and ZnO:1.0Ca presented the highest percentages of cell viability, decreased ROS and NO production in +LPS cells, and maintenance of NO production at basal levels.

• Economic and Environmental Geology
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• v.57 no.4
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• pp.387-396
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• 2024

The geological disposal of high-level radioactive waste (HLW) involves permanently isolating the wastes in stable geological formations deep underground. Mudstone (siltstone and claystone) containing abundant clay minerals is proposed as a host rock for geological disposal of HLW because clay minerals have low permeability and high ion sorption/exchange capacity. Despite the widespread occurrence of sedimentary basins in Korea, there is a lack of evaluation of mudstone as host rocks for geological disposal. In this study, we utilized the JBH-1 borehole (7-754 m) obtained from the Jinju Formation to investigate the distribution trend and mineral compositions of mudstone. Additionally, we conducted comparative analyses with the Opalinus Clay in Switzerland considered as host rock of geological disposal of HLW. Claystone containing more than 40% clay minerals exhibit thick layers primarily in the upper section (7-350 m) of the JBH-1 borehole. While the clay minerals content of claystone does not show significant variation with depth, there are differences in the characteristics of feldspar and carbonate minerals. These mineralogical variations can led change in pore water chemistry and rock mechanical properties. The clay minerals content of claystone in the Jinju Formation is similar to that of the Opalinus Clay. However, there are notable differences in clay minerals composition. While the Opalinus Clay contains smectite-illite mixed-layer minerals, the Jinju Formation are dominated by illite indicating higher burial temperatures. This information will be useful for studying the host rock of HLW geological disposal site in Korea.

• Journal of the Korean Electrochemical Society
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• v.17 no.2
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• pp.111-118
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• 2014

The electrochemical properties using the cells assembled with the synthesized $LiCoO_2$(LCO) were evaluated in this study. The LCO was synthesized from high-purity cobalt sulfate($CoSO_4$) which is recovered from the cathode scrap in the wastes lithium ion secondary battery(LIB). The leaching process for dissolving the metallic elements from the LCO scrap was controlled by the quantities of the sulfuric acid and hydrogen peroxide. The metal precipitation to remove the impurities was controlled by the pH value using the caustic soda. And also, D2EHPA and $CYANEX^{(R)}272$ were used in the solvent extraction process in order to remove the impurities again. The high-purity $CoSO_4$ solution was recovered by the processes mentioned above. We made the 6 wt.% $CoSO_4$ solution mixed with distilled water. And the 6 wt.% $CoSO_4$ solution was mixed with oxalic acid by the stirring method and dried in oven. $LiCoO_2$ as a cathode material for LIB was formed by the calcination after the drying and synthesis with the $Li_2CO_3$ powder. We assembled the cells using the $LiCoO_2$ powders and evaluated the electrochemical properties. And then, we confirmed possibility of the recyclability about the cathode materials for LIBs.

• Applied Biological Chemistry
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• v.15 no.1
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• pp.49-57
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• 1972

Varietal difference in root distribution and other root characteristics were investigated under fold and water culture condition. The results were as follows: 1. IR667 showed funnel type of root distribution in soil profit while Jinheung had barrel type, and each type appearance was more distinguishable with fertilizer application. 2. Root weight per tiller was smaller in IR667 than in Jinheung and IR667 had more root in 0 to 5cm of soil depth but Jinheung had more in 5 to l0cm depth. 3. Horizontal distribution of root was dencer near to stem base without fertilizer than with fertilizer in both IR667 and Jinheung indicating structural construction for intensive nutrient uptake. Between varieties this 'dence to stem base' trend accompaning 'dence to wide spacing side' was greater in IR667 without fertilizer and these were quite true with fertilizer in Jinheung. 4. The decreasing rates of root and ear weight by fertilizer application were greater in IR667 than in Jinheung. This and other characteristics indicated that the root of IR667 is likely to be panicle-number type comparing with Jinheung. 5. The root of IR667 had lower oxidizing power of ${\alpha}-naphthylamine$ than that of Jinheung indicating weaker resistance to reductive soil but cation exchange capacity of water-cultured root was higher in IR667 suggesting stronger nutrient uptake. 6. The content of phosphorus and especially potassium in root were higher with fertilizer but lower without fertilizer in IR667 than in Jinheung indicating that IR667 is more sensitive to root environment. 7. The contents of N, K and CEC were increasing toward root tip while P content was decreasing. The root from surface soil had higher N and K content than that from subsoil. The contents of N,P,K, and CEC of root at harvesting stage were about 1.0%, 0.1%, 0.5% and 15me/100g at dry weight base, respectively.

• The Korean Journal of Nuclear Medicine
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• v.33 no.6
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• pp.527-536
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• 1999

Purpose: Radiotracers that bind to the central benzodiazepine receptor are useful for the investigation of various neurological and psychiatric diseases. [C-11]Flumazenil, a benzodiazepine antagonist, is the most widely used radioligand for central benzodiazepine receptor imaging by PET. We synthesized 3-(2-[F-18]fluoro)flumazenil, a new fluorine-18 ($t_{1/2}$= 110 min) labeled analogue of benzodiazepine receptor imaging agent, and evaluated in vivo for biodistribution in mice. Materials and Methods: Flumazenil (Ro 15-1788) was synthesized by a modification of the reported method. Precursor of 3-(2-[F-18]fluoro)flumazenil, the tosylated flumazenil derivative was prepared by the tosylation of the ethyl ester by ditosylethane. [F-18] labeling of tosyl substitued flumazenil precursor was performed by adding F-18 ion at $85^{\circ}C$ in the hot ceil for 20 min. The reaction mixture was trapped by C18 cartridge, washed with 10% ethanol, and eluted by 40% ethanol. Bidistribution in mice was determined after intravenous injection. Results: The total chemical yield of tosylated flumazenil derivative was ${\sim}40%$. The efficiency of labeling 3-(2-[F-18]fluoro)flumazenil was 66% with a total synthesis time of 50 min. Brain uptakes of 3-(2-[F-18]fluoro)flumazenil at 10, 30, 60 min after injection, were $2.5{\pm}0.37,\;2.2{\pm}0.26,\;2.1{\pm}0.11$ and blood activities were $3.7{\pm}0.43,\;3.3{\pm}0.07,\;3.3{\pm}0.09%ID/g$, respectively. Conclusion: We synthesized a tosylated flumazenil derivative which was successfully labeled with no-carrier-added F-18 by nucleophilic substitution.

• Journal of the Korean Chemical Society
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• v.48 no.5
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• pp.473-482
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• 2004

The homobimetallic anion, $M^+({\eta}^5-MeCp)Mn(CO)_2Mn(CO)_5^-(M^+=Na^+,\;PPN^+)$was disrupted by CH2CHCH2Cl in THF at various temperatures ($20^{\circ}C~50^{\circ}C$) under the pseudo 1st order reaction conditions where excess of allyl chloride was employed under a nitrogen atmosphere. This homobimetallic anion seems to be involved in a concerted reaction mechanism in which a four-centered transition state is proposed. After undergoing the transition state, this reaction eventually leads to (MeCp)Mn$(CO)_3$ on addition of CO and $({\eta}^1-allyl)Mn(CO)_5$, respectively. However, in case of $Na^+$ analog, $Na^+$ may play a novel counter ion effect on the disruption reaction either by transferring one terminal CO from the $Mn(CO)_5$ moiety on to the $({\eta}^5-MeCp)Mn(CO)_2$of the corresponding homobimetallic complex, eventually resulting in $({\eta}^5-MeCp)Mn(CO)_3$ or through the interaction between $Na^+$ and the leaving group (Cl) of allyl chloride. This reaction is of overall second order with respect to homobimetallic complex with the activation parameters (${\Delta}H^{\neq}=17.15{\pm}0.17kcal/mol,\;{\Delta}S^{\neq}=-9.63{\pm}0.10$ e.u. for $Na^+$ analog; ${\Delta}H^{\neq}=22.13{\pm}0.21 kcal/mol,\;{\Delta}S^{\neq}=9.74{\pm}0.19$ e.u. for $PPN^+$ analog reaction).

• Applied Biological Chemistry
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• v.15 no.2
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• pp.111-142
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• 1972

An experimental Chung-Kook-Jang was prepared using the strain Bacillus subtilis sp. isolated by the author Samples were taken in 12 hrs interval during the fermentation and the oligopeptides were separated by the method of molecular sieving using the ion exchange resin column of Dowex-50. Only the X-16 fraction of oligopeptides was taken and the components of oligopeptides were developed in two dimensional thin layer chromatograms. The each peptide spot was eluted and each peptide was isolated. The pattern and kinds of amino acids, and N and C-terminal amino acids were studied. Fourteen different oligopeptides could be detected by the two dimensional thin layer chromatography, all of which were consisted of $4{\sim}9$ kinds of amino acids. No dipeptides and no tripeptides could be found. The N and C-terminal amino acids and the residual component amino acids of all these 14 peptides could be summarized as the follows. [P]-I. Pro (Cys Ala Asp Trp Ile Val) Glu [P]-II. Val (His Arg Glu Thr Ala Met) Asp [P]-III. Glu (Cys Lys Asp Thr Met) Ala [P]-IV. Glu(His Ser Ala) Met) [P]-V. Ile (Cys Asp Arg Gly Pro T.p Phe) His [P]-VI. Gly(Asp ser) Lys [P]-VII. Thr(Pro Tyr Phe) Asp [P]-VIII. Phe(Tyr Leu Ile) Val [P]-IX. Trp (Phelle) Thr [P]-X. Ile (Arg Leu) Phe [P]-XI. Asp (Lys His Ser Gly Glu Pro) Ala [P]-XII. Glu (Cys Asp Gly) Ser [P]-XIII. Ala (Arg Tyr) Glu [P]-XIV. Met (Glu Ala) His It appears that the protease of the Bacillus subtilis K-27 syrain has rather wider range of specificity than proteases of Aspergoillus soya, pepsin, chymotrypsin, and trypsin.

• Applied Biological Chemistry
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• v.39 no.6
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• pp.494-500
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• 1996

Uptake of hen metal ions by water dropwort (Oenanthe stolonifera DC.) and its cadmium-binding protein were studied to probe for good method to remove heavy metal contaminants from environments. The plant was cultured in the culture medium (pH 7.0) containing the various concentrations of $Cd^{2+}$, $Cr^{3+}$ or $Pb^{2+}$, for 3 and 7 days. The residual heavy metals deposited in roots linearly increased as the metal ions concentration increased up to 17 ppm for $Cd^{2+}$, 20 ppm for $Cr^{3+}$ and 50 ppm for $Pb^{2+}$. Above these concentrations, the plant growth was inhibited and the uptake rates of the metal ions decreased. The heavy metals absorbed by the plant were mostly deposited in roots. In particular, the residual concentration of lead in roots was about four times higher than those of cadmium and chromium. When cultured in the medium containing 20 ppm of each metal ion, 80% of cadmium, 90% of cromium and 96% of lead were deposited in roots out of the total residual metal ions in the plant. These values correspond to 6.1 mg of cadmium, 5.2 mg of chromium and 23.6 mg of lead per one gram of roots tissue on a dry weight basis. A cadmium-binding protein was partially purified by extraction, gel filtration and DEAE-Cellulose chromatography from water dropworts that was grown in the medium containing 20 ppm $Cd^{2+}$. The purified protein was a single band on SDS- and non-denaturing- polyacrylamide gel electrophoresis. Its molecular mass was estimated to be ca. 5,000 dalton by gel filteration. Analysis of amino acid composition of the protein indicated that it had a typical amino acid composition of heavy metal-binding protein in that it contained 27% of acidic amino acids and 9.9% of cysteine. However, it is likely that the protein is a new plant metal-binding protein, since its amino acid composition is somewhat different from those of phytochelatins that have been known so far.