• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.712-718
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• 2009

To look into the degree of the long distance movement of the air pollution within Mt. Kyebang, Hongcheon, one of the clean regions, major ions, components of collected wet precipitation, were analyzed by using the ion chromatography after measuring pH and electrical conductivity. The quality assurance of chemical composition data was checked by considering the ion balance and electrical conductivity. Also, the pH of precipitation showed in the pH5.0~5.5 range, less than the pH5.6 in which the standards of the acid precipitation. On the whole, the more precipitation got, the less ion concentration became.: It could showed what it influenced on the fluctuation of the precipitation pH according to fluctuation and neutralization of the according materials. In the meantime, as composition ratios of wet deposition, ${SO_4}^{2-}$ and $nss-{SO_4}^{2-}$, ${NH_4}^+$ and $nss-Ca^{2+}$ accounted for high percentage. Especially, as the concentration of ${SO_4}^{2-}$, the artificial pollutant, and $Ca^{2+}$, the soil substance, showed high, Mt. Kyebang, Hongcheon having barely fixed air-pollutants sources was most likely to be influenced by the pollutants moved from long distances.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.1
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• pp.75-84
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• 2005

The aim of this study is to evaluate the leaching characteristics of lead, copper, cadmium, and mercury from steel making slag by seawater. To demonstrate the leaching characteristics of heavy metals from steel making slag by seawater, it was carried to various leaching tests such as regular leaching tests, liquid/sold(LS) leaching test and pH static test. From the leachability of $Pb^{+2},\;Cu^{+2},\;and\;Cd^{+2}$ from steel making slag in pH static test, it is distinguished between distilled water and seawater. With distilled water, it is very low between pH 7-8 and pH 11-12. On the other hands, with the seawater, its leaching is higher than that of distilled water. In particular, concentration of $Hg^{+2}$ leached from slag by seawater is lower than that of distilled water. Meanwhile, we found that the heavy metals from steel making slag would be dissolved and precipitated using geochemcial equilibrium program such as visual minteq. Lead and copper leached from steel making slag with seawater were dissolved nearly in the range of pH 11-12, but in the range of pH 7-10 those were precipitated about 90%. And cadmium leached from steel making slag with seawater were dissolved completely. On pH static test with distilled water, lead leached from steel making slag seemed to be similar to pH static test with seawater. However, copper and cadmium leached from steel making slag were dissolved. In general, the species of lead leached from steel making slag were formed mainly of $PbCl^+,\;PbSO_4$, the species of copper were formed mainly of $CuSO_4,\;CuCO_3$, the species of cadmium were formed mainly of $CdCl^+,\;CdSO_4$ due to being sorbed with the anions($Cl^-,\;CO_3^{-2},\;SO_4^{-2}$) of the seawater. Both pH static test with seawater and distilled water, it is not in the case of the mercury. Most of mercury leached from steel making slag was precipitated(SI=0). Because the decreasing of $Hg^{+2}$ concentrations depends ferociously on the variation of chloride($Cl^-$) existed in the seawater. $Hg^{+2}$ leached from steel making slag could be sorbed strongly with chloride($Cl^-$) compared of carbonate($CO_3^{-2}$) and sulfate($SO_4^{-2}$) in the seawater. On the basis of that result, we found that the species of mercury was formed of calomel($Hg_2Cl_2$) as one of finite solid. Due to forming a calomel($Hg_2Cl_2$) in the seawater, the stability of mercury species by steel making slag should be higher than those of lead, copper, and cadmium species. Regarding the results stated above, we postulated that the steel making slag could be recycled to sea aggregates due to being distinguishing leachability of heavy metals($Pb^{+2},\;Cu^{+2},\;Cd^{+2},\;and\;Hg^{+2}$) between leaching tests by distilled water and seawater.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1154-1158
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• 2012

A room-temperature ionic liquid (RTIL) derived from 1,4-diazabicyclo[2.2.2]octane (DABCO) consisting of tetrafluoroborate anion, 1-butyl-4-(4-sulfonylbutyl)-1,4-diazoniabicyclo[2.2.2]octane hydrogen sulfate tetrafluoroborate ($[C_4DABCOC_4SO_3H][BF_4][HSO_4]$) was synthesized and catalytically evaluated in the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes by cyclocondensation reaction of ${\beta}$-naphthol and aryl aldehydes. This novel RTIL with an acidic $SO_3H$ group showed high catalytic activity with good to excellent yields of the desired products in short reaction times. Moreover, the catalyst could be recovered and reused at least three times with only slight reduction in its catalytic activity.

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.145-152
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• 2013

The culture conditions to maximize the production of endoglucanase (EC 3.2.1.4) from the brown rot fungus Fomitopsis pinicola MKACC 54347 mycelia were investigated. Among the tested media for endoglucanase production, Mandel's mineral salts medium (MSM; 1% cellulose, 0.1% peptone, 0.14% $(NH_4)_2SO_4$, 0.03% urea, 0.2% $KH_2PO_4$, 0.03% $MgSO_4{\cdot}7H_2O$, 0.03% $CaCl_2$, and 0.1% trace metal solution (19.8 mM $FeSO_4$, 13.0 mM $MnSO_4$, 12.2 mM $ZnSO_4$, and 15.4 mM $CoCl_2$)) produced the highest activity of the enzyme. To optimize the medium composition for enzyme activity, the effects of various carbon, nitrogen, phosphorus, and inorganic sources were investigated in MSM. Maximal enzyme production was accomplished using a medium containing 2% carboxymethyl cellulose (CMC), 2% yeast extract, 0.2% $KH_2PO_4$, 0.03% $MnSO_4$, and 0.3% trace metal solution. Different physiological conditions, like incubation period and temperature, were also examined to assess their influence on enzyme production. Enzyme production from F. pinicola reached its highest level after cultivation for 8 days at $25^{\circ}C$. Nondenaturing polyacrylamide gel electrophoresis (PAGE), followed by the endoglucanase activity staining using CMC as the substrate, was performed to identify the endoglucanase under the culture conditions studied. Zymogram analysis of the culture supernatant revealed an endoglucanase band with a molecular mass of 52 kDa. The optimum pH and temperature for enzyme activity were $55^{\circ}C$ and pH 5.0, respectively.

• Korean Journal of Crystallography
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• v.8 no.1
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• pp.1-5
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• 1997

The crystal structure of the title compound consists of discrete 4-N,N-dimethylamino-4'-N'-methyl-stilbazolium, $C_{16}H_{19}N_2$, and tosylate, $C_7H_7SO_3$, dimer. The 4-N,N-dimethylamino-4'-N'-methyl-stilbazolium molecule has a trans conformation at the central C=C double bond: the dihedral angle between the phenyl and the pyridyl rings is $5.7(2)^{\circ}$ and the whole molecule is planar within $0.138(8){\AA}$. Tosylate molecules display hydrogen-bonded dimers with the O-H...O distances of 2.855(9) and $2.899(8){\AA}$, respectively. The shortest intermolecular contact is the distance $3.10(1){\AA}$ between O(3) and C(16).

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.173.2-173.2
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• 2011

대체 에너지 자원 중 폐기물의 소화 가스를 이용한 바이오가스 발전은 이산화탄소에 비해 온실효과 영향력에 21배에 해당하는 메탄가스를 연료로 사용하여 환경부하를 저감시키고 에너지를 생산한다. 바이오가스에 포함된 $H_2S$는 연소 후 $SO_2$형태로 발생되는데 $SO_2$는 수분과 반응을 하게 되면 $H_2SO_4$등의 강한 산성을 띄는 물질로 생성되어 배관 및 발전기에 손상을 주고 저온부식현상을 유발하게 하며, 동물이나 인체에 노출되면 기관지 수축현상이 일어나 호흡기에 영향을 주는 질식성을 띄는 가스이다. 축산바이오가스에 포함된 $H_2S$의 함유량과 가스엔진의 연소 시 배출되는 $SO_2$ 배기가스 성분의 관련성을 검증하기 위해 60-65%의 $CH_4$와 30-35%의 $CO_2$ 성분의 바이오가스를 50kW급 발전기에서 사용하였고 연소 후 배출되는 가스 성분을 분석하였다.

• Journal of Plant Biology
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• v.25 no.3
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• pp.135-151
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• 1982

This investigation was carried out to clarify the changes of pigments and soluble protein, and photosystem II activity in the leaves of barley (${SO}_2$-sensitive) and corn (${SO}_2$-resistant) seedlings induced by the ${SO}_2$ fumigation (10, 50ppm). The pH changes of the leaf extract, the content of sulfite and sulfate, the activities of catalase, peroxidase, and polyphenoloxidase were compared in the leaves of barley and corn seedlings induced by ${SO}_2$ fumigation. The results are summarized as follows: An appreciable effect of pH change of leaf extract by ${SO}_2$ fumigation was observed in barley leaves (pH 6.10 to 5.18), but only a small change occurred in corn leaves (pH 5.66 to 5.50). The same pattern of pH changes was recorded when the solution of 0.2N HCl was added to leaf extract, providing lower buffering capacity of the barley leaves than corn leaves. After 2 hours of exposure to 10 ppm ${SO}_2$, the contents of ${SO}^{2-}_3$ and ${SO}^{2-}_4$ were increased in barley leaves, while only ${SO}^{2-}_4$ increased in corn leaves. After fumigation with 10ppm ${SO}_2$ for 2 hours, barley leaves showed significant decreases in activities of catalase, to 17% peroxidase, to 58%, and polyphenoloxidase, to 88%. Corn leaves showed increases in activities of peroxidase, to 136%, and polyphenoloxidase, to 128%. Absorption spectra of pigments obtained from ${SO}_2$-fumigated leaves were gradually decreased with the fumigation time increases, but the decrease was more significant in barley leaves. Fumigation with 50ppm ${SO}_2$ for 2 hours induced the greatest decomposition in carotenoid, followed by chlorophyll a and then chlorophyll b in barley leaves. The ratio of chlorophyll a/b was decreased from 4.1 to 3.6 in barley leaves, but in corn leaves it was maintained almost a constant level(4.9-4.8). The rate of decomposition of chlorophyll and carotenoid in corn leaves was very slow than those in the barley leaves. Fumigation with 50 ppm ${SO}_2$ for 2 hous, decreased the protein content of barley leaves to 59%, and that of corn leaves to 89%, and the extent of decrease in protein content was greater than that of pigments in barley and corn leaves. The rate of DCIP9dichlorophenol indophenol) photoreduction in ${SO}_2$-fumigated leaves was decreased to 18 and 67% in barley and corn leaves, respectively. However, DCIP photoreduction was considerably recovered about 32 and 92% with the addition of DPC(diphenylcarbazide) as an exogenous electron donor in barley and corn leaves, respectively.

• Journal of Microbiology and Biotechnology
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• v.10 no.3
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• pp.419-422
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• 2000

A three-phase fluidized-bed bioreactor including Thiobacillus sp. IW was tested to remove H_2S and $NH_3$ simultaneously. The inlet $H_2S$ was oxidized to $SO_4^{2-}$ by Thiobacillus sp. IW, and the $NH_3$ reacted with the $SO_4^{2-}$ to form $(NH_4)_2SO_4$. The removal efficiency of $H_2S$ was 98.4-99.9% for an inlet concentration of 36-730 ppm and that of $NH_3$ was 60.2-99.2% for an inlet concentration of 45-412 ppm. The removal efficiency of $NH_3$ was reduced when the inlet loading rate of $NH_3$ was increased above 10 mg/l/h. When the bioreactor was operated for 25 days with a lower inlet concentration of $NH_3$ compared with the of $H_2S$, the bioreactor exhibited an excellent performance with a stable pH, dissolved oxygen content, and cell concentration.

• Resources Recycling
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• v.23 no.2
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• pp.17-25
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• 2014

The thermal effect on the compositional change of the $SO_2$ absorption process product was investigated compared with the composition of raw material when dolomite is employed in place of lime in the scrubbing process based on thermodynamic estimation. It was considered that the equilibrium reactions which directly related with the formation of $CaSO_4$ and $MgSO_4$, the absorption process products, are those between $Ca^{2+}$ and $Ca(OH)_2$, $Mg^{2+}$ and $Mg(OH)_2$, and the secondary dissociation reaction of $H_2SO_4$. It was thought to be necessary to examine the enthalpy change for the formation reactions of $CaSO_4$ and $MgSO_4$ along with the thermal feature of the relative reactions to figure out the influence of temperature on the compositional change of absorption process products. The stable regions for $Ca(OH)_2$ and $Mg(OH)_2$ in Pourbaix diagram were found to be increased as temperature rises and the equilibrium reaction between $Ca^{2+}$ and $Ca(OH)_2$ was investigated to be more strongly influence by temperature change compared with the equilibrium reaction between $Mg^{2+}$ and $Mg(OH)_2$. The amounts of $CaSO_4$ and $MgSO_4$ were anticipated to be decreased with temperature considering the thermal characteristics for the equilibrium reactions regarding calcium, magnesium, and $H_2SO_4$. It was understood that the formation ratio between $CaSO_4$ and $MgSO_4$ is greater than the composition ratio between calcium and magnesium contained in dolomite at specific temperature and the decrease of the formation ratio of $CaSO_4$ and $MgSO_4$ with temperature was estimated to be diminished as the content of calcium in dolomite is increased. In addition, the extent of the change in the compositional ratio between absorption process products was examined to be reduced compared with the composition of raw material as the calcium content in dolomite is raised.

• The Korean Journal of Mycology
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• v.24 no.3 s.78
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• pp.214-222
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• 1996

This study was carried out to obtain the basic data on artificial culture of Phellinus linteus. The optimum condition for the mycelial growth was $25{\sim}30^{\circ}C$ and pH $6.0{\sim}7.0$. The carbon sources such as D-glucose, D-mannose and Dextrose were favorable to mycelial growth. As nitrogen sources, peptone, cassamino acid and glutamic acid appeared to be favorable. The optimum C/N ratio was about 20:1, when 2% of glucose was provided as a carbon source. The better organic acids and vitamin among tested ones were gallic, silicic acids and biotin. The mineral nutrients of $KH_2PO_4,\;FeSO_4{\cdot}7H_2O,\; MgSO_4{\cdot}7H_2O,\;ZnSO_4{\cdot}7H_2O$ were effective and the optimum concentrations were 0.05, 0.001, 0.02 and 0.003%, respectively.