• Journal of agriculture & life science
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• v.46 no.3
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• pp.1-10
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• 2012

This study was carried out to provide basal information on factors effected the decline of Pinus thunbergii by analysisof, the content of chlorophyll, and acid deposition through stepwise regression analysis. pH in throughfall at industrial area was 4.65 in the spring and 4.72 in the fall. On the contrary, pH at rural area was measured 5.32 in the spring and 5.34 in the fall. EC of rain fall at industrial area was $262.30{\mu}s$, However, there was $47.72{\mu}s$ at control area. Of anions, the concentration of ${NO_3}^-$ was $52.13mg/{\ell}$ at industrial area and $37.85mg/{\ell}$ at area. The concentration of ${SO_4}^{2-}$ was $57.89mg/{\ell}$ at industrial area and $36.21mg/{\ell}$ at area. Of the concentration of leaf chlorophyll in Pinus thunbergii, chlorophyll a was 0.2378 but control area was 0.4378. Also the content of chlorphyll b was 0.2097 and control area was 0.2345. The degree of decline of Pinus thunbergii forest was 2.97 at industrial area and 1.20 at area. We carried out a correlation analysis between the degree of decline and the concentration of ions, $SO_2$, and $NO_2$ in Pinus thunbergii forest. As a result, there was a negative correlation (r=-0.8672) between rain acids, and a positive correlation between $SO_2$ concentrations (r=0.8924) and between $NO_2$ concentrations (r=0.8428) in air. The correlations among acid depositions at level of 1% were pH (r=-0.8672), ${NO_3}^-$(r=0.6996), ${SO_4}^{2-}$(r=0.8497), $SO_2$ (r=0.8924), and $NO_2$ (r=0.8428).

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.4
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• pp.459-467
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• 2006

This study was carried out to characteristics and distributions of acid deposition in Korea. Precipitation was collected by acid deposition monitoring networks and analyzed for pH, conductivity, and following major ionic components $SO_4^{2-}$, $CI^-$, $NO_3^-$, $NH_4^+$, $Na^+$, $K^+$, $Ca^{2+}$, $Mg{2+}$. During the investigation period, Volume weighted annual mean pH of precipitation in Korea is 4.8, showing slightly acidic level. The amount of rainfall in the range of pH 5.1$\sim$5.5 charged approximately 28% of annual precipitation,23.4% in pH 4.6$\sim$5.0, and contributed 16.2% under pH 4.5. Among seasons, alkaline precipitation has occurred more often in spring, meanwhile acidic precipitation in which pH is under 4.5 has frequently occurred in autumn. Volume weighted annual mean concentrations of $SO_4^{2-}$, $NO_3^-$, $CI^-$ are 2.558 mg/L, 1.590 mg/L, 1.286 mg/L respectively, and provided that $SO_4^{2-}$, is the major contributor, followed by $NO_3^-$, $CI^-$. In case of cation, annual mean concentration for $NH_4^+$, $Na^+$, $K^+$, $Ca^{2+}$, $Mg{2+}$, $H^+$ are 0.693 mg/L, 0.528 mg/L, 0.439 mg/L, 0.455 mg/L, 0.089 mg/L,0.015 mg/L, and $NH_4$ were decided as the main contributor, followed by $Na^+$, $K^+$, $Ca^{2+}$, $Mg{2+}$, $H^+$. Annual wet deposition rate for sulfate, nitrate and ammonia are $3.316gm^{-2}yr^{-1}$, $2.057gm^{-2}yr{-1}$, $0.894gm^{-2}yr{-1}$, respectively, and it was founded that the deposition flux in summer contributes about 38.42% to 67.62% to total deposition.

• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.23-34
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• 1986

To find antitumor components of Lyophyllum decastes, the mycelia of L. decastes were cultured in artificial media and a new antitumor component which showed potent antitumor activity against sarcoma 180 implanted in mice, was isolated and named 'Lyophyllan A'. Lyophyllan A was composed of a polysaccharide moiety (86%) and a protein moiety (2%). The polysaccharide moiety was found to be a heteroglycan which consisted of glucose (48.1%), mannose (30.8%), galactose, xylose and fucose. The protein moiety contained 18 amino acids. Cultural characteristics of L. decastes were investigated by shake culture method. The best result was obtained when L. decastes was cultured in medium glucose 50g, peptone 10g, corn steep liquor 30ml, $KH_2PO_4$ 0.87g, $MgSO_4$ $7H_2O$ 0.5g, $CaCl_2$ 0.3g, $FeSO_4{\cdot}7H_2O$ 10mg, $MnCl_2{\cdot}4H_2O$ 7mg, $ZnSO_4{\cdot}7H_2O$ 4mg and $CuSO_4{\cdot}5H_2O$ 1mg per one liter at $26^{circ}C$, 180rpm, for 9 days.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.296-313
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• 2014

A QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) multiresidue method was developed for the simultaneous analysis of 124 pesticides in soil by LC-MS. The procedure involved liquid extraction of soil immersed with 0.2N $NH_4Cl$ by acetonitrile with 1% acetic acid, followed by anhydrous $MgSO_4$ and sodium acetate, and dispersive SPE cleanup with $MgSO_4$, primary secondary amine (PSA) and $C_{18}$. The extracts were analyzed with LC-MS/MS in ESI positive mode. Standard calibration curves were made by matrix matched standards and their correlation coefficients were higher than 0.99. Recovery studies for the validation were carried out using two type soils, loam and sandy loam, at four concentration levels (0.005, 0.01, 0.02, and 0.1 mg/kg). The recoveries of pesticides were in the range of 70-120% with < 20% RSD except 4 pesticides, Benfuracarb, Ethiofencarb, Pymetrozine, and Pyrethrin. This result indicated that the method using QuEChERS and LC-MS/MS could be applied for the simultaneous determination of pesticide residues in soils.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.20-27
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• 2001

Stream water chemistry in the abandoned Boeun Jeil coal mine area was studied for a period of 3 months, including rainy and dry season. The stream waters were a nearly neutral and slightly alkali condition, and $Mg-SO_4$ type with Mg>Ca>Na>K and $SO_4>HCO_3>Cl>NO_3$. Chemical composition of the stream water was quite irregular during the experimental period. Concentrations of Na, K, $HCO_3$, U, Sr, and Cr decreased by $10{\sim}30%$ during rainy season, caused by dilution effects with rain. The concentration of Ca, Mg, $NO_3$, Cd, and Co increased during the rainy season, caused by more easily dissolved from bedrocks or mine drainage with slightly acidic condition than dry season. The stream water was enriched in Mg, Ca, $HCO_3$, $SO_4$, Al, Fe, Zn, Ni, Co, Cr, Cd, Sr and U. Concentrations of Na, Mg, Ca, $SO_4$, $HCO_3$, Fe, Zn, Ni, Sr, and U decreased linearly with distance from the mine adit. These elements were strongly controlled by dilution of unpolluted water influx and/or adsorption on the clay minerals and iron oxyhydroxide precipitates. This mine area exhibited two main weathering processes ; 1) oxidation with acidification derived from Fe sulphides, and 2) pH buffering due to Ca and Mg carbonate dissolution. This weathering processes were followed by adsorption of metals on iron oxyhydroxides and precipitation.

• Biomedical Science Letters
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• v.8 no.2
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• pp.71-75
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• 2002

Paraquat (N,N'-dimethyl-4,4'-bipyrrimidinium-dichlorides (PQ): MW 186.6) has been used to killing verierty of hubside plants. For this study were use Sprague-dawely rats (190$\pm$10 gm) and injection 40 mg/kg BW of paraquat (LD$_{50}$) to 24 hrs PQ and 4 days PQ group excepte normal control. For the measurement of blood calcium Ino-phosphorus and activity of alkaline phosphatase (ALP) by HITTACH 746. In serum phosphoruse of normal control were 8.0$\pm$1.2 mg/dl and 24 hrs PQ group were 8.9$\pm$1.0 mg/dl (P<0.05) and 4 days PQ group were 8.8$\pm$0.42 gmm/dl (P<0.05). In serum phosphorus were very sensitive uptaked to 10% within only 24 hours, but 4 days of PQ were similar uptake level than 24 hrs PQ. So this 8.9 mg/dl of sem phosphorus may be thought threshold level becouse does not more encrease. In blood calcium normal of rats were measured 9.51$\pm$0.3 mg/dl and 24 hrs of PQ group were 9.9$\pm$0.51 mg/dl (uptaked 4.5%, p>0.05). This uptake cannot fined meaning mathmatic statistics but 4 days PQ groups of calcium were 10.43$\pm$0.37 gm/dl (uptaked 10%, p<0.05). That 24 hrs PQ groups of caclium dose not reacted sensitive to irritated by PQ. So, when use oxidants of PQ, the blood calcium and Ino-phosphorus were linear correlated uptake that reasone thought may be move out form hardness bone tissue to in blood it does not take feeding to hunger for 4 days. In ALP normal of rats were measured 991$\pm$106 unit/L. In 24 hrs irritated PQ rats were fall down by 629$\pm$91 unit/L (P<0.001) but in 4 days of PQ rats were 792$\pm$85 unit/L (P<0.0011) that the activity of level were mild recovered activity from 629 unit (63%) to 792 unit (80%). So, that the reasone of ALP were very sensitive activity and reverse correlated to blood calcium or phosphorus irritated by PQ.

• Journal of the Korean Applied Science and Technology
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• v.28 no.4
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• pp.455-463
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• 2011

The average sulfur content of crude oil is 2.2%. Coal is about 0.3 to 4.0 percent of the sulfur gases or particles being discharged into the atmosphere through the chimney as 1 to 2% $SO_3$(Sulfur trioxide) and about 95% of the $SO_2$ is reported. $SO_3$ gas, which has many different causes of, as the combustion of sulfur containing fuel during the air due to the excess $SO_2$ gas is oxidized to $SO_3$ gas. Sulfur trioxide emitted from high sulfur heavy oil fired boiler caused white plume in stack and high temperature and cold end corrosion of facilities. So, in order to control sulfur trioxide concentration of Fuel gas in boiler, various of additives are used in other foreign. They are injected to Fuel Oil and consumed in boiler and reduce ash and the conversion rate of sulfur trioxide. In domestic, MgO compounds are used as additives but the total volume of them are made from other foreign company. In this study, MgO compounds were developed with liquid MgO compounds and field application was accomplished. The effect of newly developed chemicals and process were nearly equal to foreign products. In Consequent, the chemicals and process produced by newly developed technology can be substituted for foreign products and reduce the cost of plant operation.

• Journal of the Mineralogical Society of Korea
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• v.31 no.2
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• pp.67-73
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• 2018

The objective of this study was to investigate the application of sulfate solvents for the economic and eco-friendly leaching of valuable metals from Au concentrate using an acid bake-water leaching system (AWS). AWS experiments were performed using an electric furnace with various baking temperatures ($100-500^{\circ}C$) and sulfate solvents ($H_2SO_4$, $K_2SO_4$, $(NH_4)_2SO_4$, $MgSO_4$, and $CaSO_4$). The efficiency of the valuable metal leaching increased as the baking temperature was increased to $400^{\circ}C$. Based on the AWS leaching time experiments, the maximum leaching rate occurred with the aqueous $(NH_4)_2SO_4$ solvent. This study demonstrates that aqueous $(NH_4)_2SO_4$ could be used as an effective solvent for valuable metal leaching using an AWS.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.155-160
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• 2004

Permeation experiments of a commercial nanofiltration membrane (nominated as ESNA 1) were carried out with aqueous solutions of various single salts, that is, five chlorides (NH$_4$Cl, NaCl, KCl, MgCl$_2$ and $CaCl_2$), three nitrates $(NaNo_3,\;Mg(No_3)_2\;and\;Ca(NO_3)_2)\;and\;three\;sulfates\;((NH_4)_2SO_4,\;Na_2SO_4\;and\;MgSO_4)$. The experimental results showed that (1) the permeate volume flux of the ESNA 1 membrane increased and decreased with the growth of the applied pressure and the feed concentration of salts, respectively. The real rejection of ESNA 1 membrane to most single salts increased with the growth of the permeate volume flux. (2) The reflection coefficients of ESNA 1 membrane to chlorides, nitrates and sulfates are 0.97, 0.96 and 0.99, respectively. The solute permeability of most salts except for magnesium and calcium salts increased with the growth of feed concentration. (3) The sequence of the rejections of ESNA 1 membrane to anions is $R({SO_4}^{2-})>R(CI)>R(NO_3)$ at the same feed concentration. While the sequence of the rejections to cations is cataloged into two cases: $R(Na^+)>R(K^+)>R(Mg^{2+})>R(Ca^{2+})$ at the concentration of 10 mol/$m^3$ and $R(Mg^{2+})>R(Ca^{2+})>R(Na^+)>R(K^+)$ at the concentration of 100 mol/$m^3$. The separation capability of a NF membrane is usually affected by the electrostatic effect and the steric-hindrance effect. In this case, the electrostatic effect is the major factor at low concentration and the steric-hindrance effect is the major factor at high concentration. Both the specific sorption and the hydration also reasonably influenced the separation performance of NF membrane to salts.

• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.427-434
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• 1998

An alkaline protease was 4-fold purified, yielding 2.3% of recovery by ammonium sulfate precipitation, CM-cellulose column chromatography and Sephadex G-100 column chromatography. The purified enzyme was estimated to be monomeric with molecular weight of about 62,000 from polyacrylamide gel eletrophoresis (PAGE) and sodiumdodecylsulfate polyacrylamide gel electrophoresis (SDS-FAGE). The optimal pH and temperature of the alkaline pretense activity were 11.0 and 50$^{\circ}C$, respectively, exhibiting high stability at pH value from 6.0 to 11.0 at 50$^{\circ}C$ for 30 minute. The alkaline pretense was activated by MnSO$_4$, CaCl$_2$, and was inhibited by CuSO$_4$, ZnSO$_4$, HgCl$_2$, EDTA and EGTA. Also, the enzyme was found to be a metaloenzyme requiring Mn$\^$2+/ as cofactor. The NH$_2$-terminal amino acid of alkaline protease was alanine. The Km and Vmax values of this enzyme for casein was 4.0 mg/$m\ell$ and 5,500 unit/$m\ell$, respectively.