• Bulletin of the Korean Chemical Society
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• v.29 no.2
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• pp.398-404
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• 2008

A new solvent polymeric membrane electrode, based on N,N'-bis(salicylidene)-2,2-dimethylpropane-1,3-diamine Ni(II) as the ionophore, was designed. The oxalate-selective electrode has the dynamic range between 1.0 10-6 M and 1.0 10-1 M with a Nernstian slope of -28.7 1.0 mV per decade. The detection limit was 6.3 10-7 M. The proposed electrode revealed good selectivities for oxalate over a variety of other anions and could be used in a pH range of 2.0-7.8. The electrode can be used for at least two months without any considerable divergence in potential. The designed electrode was applied as an indicator electrode in the potentiometric determination of oxalate in real samples.

• Journal of the Korean Chemical Society
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• v.29 no.2
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• pp.178-182
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• 1985

The purpose of this study was to develop a separation method of Zn(II), Cu(II) and Mg(II), by ion exchange chromatography using cation exchange resion (Dowex 50w${\times}$8, 80-100 mesh) and anion exchange (Amberlite IRA-400). Ion exchange resions were packed into 25 ${\times}$ 2cm ID column and flow rate was controlled to 0.30 ml/min. Good eluents for separation of nonferrous metal ions such as Zn(II), Cu(II), Mg(II) were as follow: 0.5M $NaNO_3$ (pH 3.1), 0.2~0.5M HCl + 50~60% Acetone, and 1M HAc + 0.1M NaAcf(pH 3.7) aqueous solution. The mixed solution of 0.1M NaAc(pH 3.7), 0.5M HCl + 50% Acetone were found to be the best eluent for step elution. Analysis of metals were determined by atomic absorption spectrophotometer. In addition, separated Zn(II) fraction was obtained by eluted with 0.12N HCl and 1.5N $NH_4OH$ aqueous solution. This solution was titrated by the E. D. T. A.

• Journal of the Korean Chemical Society
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• v.32 no.4
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• pp.333-341
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• 1988

The bio-electrode for cytosine has been constructed by immobilizing Proteus mirabilis and Citrobacter freundii on an ammonia gas-sensor. Bacteria containing cytosine deaminase convert one molecule of cytosine into one molecule of ammonia. The Proteus mirabilis bacterial electrode showed linear response to cytosine concentration in the $1.0{\times}10^{-3}\;-\;5.0{\times}10^{-2}$M with a slope of 45-48 mV/decade in 0.2 M phospbate buffer solution at pH 8.4. The Citrobacter freundii bacterial electrode showed linear response to cytosine concentration in the $7.0{\times}10^{-5}\;-\;7.0{\times}10^{-3}$M with a slope of 48 mV/decade in 0.05M phosphate buffer solution at pH 7.6. These electrode were investigated for the effects of pH, temperature, buffer solutions, amounts of bacteria, interferences, inorganic salts and lifetime.

• Journal of the Korean Chemical Society
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• v.54 no.2
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• pp.198-207
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• 2010

The construction and performance characteristics of doxepin hydrochloride selective electrodes were developed. Three types of electrodes: plastic membrane I, coated wire II, and coated graphite rod III were constructed based on the incorporation of doxepin hydrochloride with ammonium reineckate. The influence of membrane composition, kind of plasticizer, pH of the test solution, soaking time, and foreign ions on the electrodes was investigated. The electrodes showed a Nernstain response with a mean slope of 57.41 ${\pm}$ 0.5, 56.22 ${\pm}$ 0.2 and 52.88 ${\pm}$ 0.7 mV at $25^{\circ}C$ for electrode I, II and III respectively, over Doxepin hydrochloride concentration range from $1{\times}10^{-2}-1{\times}10^{-6}M$, $5{\tims}10^{-2}-1{\times}10^{-6}M$ and $1{\times}10^{-3}-5{\times}10^{-6}M$, and with a detection limit $5.0{\times}10^{-7}M$, $6.3{\times}10^{-7}M$ and $2.5{\times}10^{-6}M$ for electrode I, II and III respectively. The constructed electrodes gave average selective precise and usable within the pH range 3 - 7. Interferences from common cations, alkaloids, sugars, amino acids and drug excipients were reported. The results obtained by the proposed electrodes were also applied successfully to the determination of the drug in pharmaceutical preparations and biological fluids.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.12-17
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• 2003

Potato blackleg disease caused by Erwinia carotovora subsp. atroseptica (Eca) has been a serious problem in Korea. Bactericidal activities of twelve bactericides including antibiotics, copper compounds and oxolinic acid were examined in vitro. Streptomycin, streptomycin sulfate, and oxolinic acid effectively controlled the pathogen at 0.02 mM. However, the pathogen developed resistance to the applied bactericides after 72 hours of incubation. Activity of copper compounds such as copper hydroxide, copper oxide and copper sulfate was lower than that of antibiotics. However, the pathogen did not develop resistant to them. Combinations of streptomycin (0.016 mM, 9.3 ppm) + copper oxide (1.2 mM, 171.6 ppm)/copper hydroxide (1.5 mM, 146.3 ppm); streptomycin sulfate (0.005 mM, 7.0 ppm) + copper oxide (1.2 mM, 171.6ppm)/copper hydroxide (1.5 mM, 146.3 ppm) were found to be effective for the control of E. carotovora subsp. atroseptica.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.825-831
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• 2007

Anti-proliferation effects of decursin from Angelica gigas Nakai were investigated in the MCF-7 cells treated with environmental hormones. The proliferation was decreased in a dose-dependent manner at the concentration over 20 ${\mu}g/mL$ in the MCF-7 cells treated with decursin of various concentrations. The environmental hormones such as $17{\beta}$-estradiol and bisphenol increased the growth of MCF-7 cells in the charcoal-treated FBS (cFBS) medium and the proliferation was the highest at 0.1 ${\mu}M$ among the tested hormone concentration. Decursin was predicted to inhibit the proliferation in a dose-dependent fashion at tested concentrations (1, 3, 10 or 30 ${\mu}g/mL$) in the MCF-7 cells added environmental hormones; however, the survival rate of the cells was lower than that of control cells that were not treated with decursin at 30 ${\mu}g/mL$ concentration. The chromatin condensation and apoptotic body were examined in the decursin treated cells cultured with the cFBS medium added environmental hormones. These results suggest that decursin decreased the proliferation through apoptosis in the MCF-7 cells added environmental hormones.

• Journal of Bio-Environment Control
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• v.7 no.4
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• pp.298-310
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• 1998

This research was carried out to find out spray characteristics of 3 types of spray nozzle to be used for greenhouse cooling. Following results were obtained from this experimental study. Water amounts sprayed with each nozzle were increased with the spraying pressure. However the increment of sprayed amount with the increase of spraying pressure were not consistent regardless of nozzle types. For the whole tested spraying pressures of nozzle-type I, II, III, the minimum droplet sizes were about 1.7~2.5$\mu$m, 1.7~2.2$\mu$m and 1.7~2.2$\mu$m, respectively, and the maximum droplet sizes were about 44~60$\mu$m, 52~71$\mu$m and 45~61$\mu$m, respectively, and the average droplet sizes were about 23~38$\mu$m, 19~24$\mu$m and 17~25$\mu$m, respectively The most appropriate spraying pressures of nozzle-type I, II, III were analyzed to be 70kgf/$\textrm{cm}^2$, 30kgf/$\textrm{cm}^2$ and 30kgf/$\textrm{cm}^2$, respectively, and their sprayed amounts were about 124mL/min, 103mL/min and 84mL/min, respectively, and average droplet sizes were 22.6$\mu$m, 21.8$\mu$m and 20.6$\mu$m, respectively. Also, with the order of nozzle-type I, II, III, droplet size distributions less than 30$\mu$m were 95.4%, 85.7% and 79.0%, respectively, and the distributions larger than 40$\mu$m were 0.2%, 1.28% and 1.67%, respectively. However most all of the droplet size were less than 50$\mu$m.

• Korean Journal of Microbiology
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• v.34 no.4
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• pp.225-230
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• 1998

This study was carried out to investigate the effect of cadmium ion on activities of cadmium-adapted malate dehydrogenase (adapted-MDH), which is defined to be an enzyme obtained from an extreme cadmium-tolerant yeast Hansenula anomaul B-7 grown in medium containing 1 mM cadmium ion. Cadmium-nonadapted malate dehydrogenase (nonadapted-MDH), which is defined to be enzyme expressed in the cells grown in $Cd^{2+}$ -free medium was also characterized by the same manner. Activities of the adapted-MDH and the nonadapted-MDH were strongly induced to 450% and to 150% in comparision with the control examined with 1 mM $Cd^{2+}$, respectively. The adapted-MDH activity was stimulated to 147%, 150%, and 135% compared with the control analyzed with 1 mM $Zn^{2+}$, 1 mM $Mn^{2+}$, and 1 mM $Ca^{2+}$, respectively and to 925%, and 250% compared with the control analyzed in the presence of 2 mM $Cd^{2+}$, and 2.5 mM $Zn^{2+}$, respectively. Km values of the adapted-MDH and the nonadapted-MDH were calculated to be the same 6.9 mM for L-malate, respectively. The Km value of the nonadapted-MDH was not changed by $Cd^{2+}$ while Vmax of the nonadapted-MDH was increased by $Cd^{2+}$. In contrast, both the Km and the Vmax values of the adapted-MDH were changed by $Cd^{2+}$.

• KCID journal
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• v.17 no.2
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• pp.57-70
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• 2010

This study was performed to analyze the affect of water supply capacity followed by allocating flood control volume in heightening reservoir, of which Baekgog reservoir was selected as a case study in here. Baekgog reservoir is located in Jincheon county, Chungbuk province, of which full water level will be heightened from EL. 100. 1m to EL. 102.1m, and total storage from 21.75M $m^3$ to 26.67M $m^3$. Flood inflow with 200year frequency was estimated to 997 $m^3$/s in peak flow and 22.54M $m^3$ in total volume. Reservoir flood routing was conducted to determine flood limited water levels, which was determined to have scenarios such as EL 97-98-99m in periods of 6.21.-7.20., 7.21.-8.20., and 8.21.-9.20., respectively, EL 97-97-97m, EL 98-98-98m in present reservoir, and EL 99-100-101m, EL 99-99-99m, and EL 100-100-100m in heightened reservoir. Reservoir inflow was simulated by DAWAST model. Annual paddy irrigation requirement was estimated to 33.19M $m^3$ to 2,975ha. Instream flow was allocated to 0.14mm/d from October to April. Operation rule curve was drawn using inflow, irrigation and instream flow requirements data. In case of withdrawal limit reservoir operation using operation rule curve, reduction rates of annual irrigation supply before and after flood control by reservoir were 2.0~4.3% in present size and 1.5~3.6% in heightened size. Reliability on water supply was decreased from 77.3% to 63.6~68.2% in present size and from 81.6% to 72.7~79.5% in heightened size. And reduction rates of water storage at the end of year before and after flood control by reservoir were 7.3~16.5% in present size and 7.7~16.9% in heightened size. But water supplies were done without any water deficiency through withdrawal limit reservoir operation in spite of low flood regulating water level.

• Journal of Pharmaceutical Investigation
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• v.19 no.2
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• pp.71-79
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• 1989

Complex formation of water-soluble polyparacyclophanes bearing two diphenylmethane or two diphenyl ether skeletons with l-anilinonaphthalene-8-sulfonate (ANS) and 2-p-toluidinylnaphthalene-6-sulfonate (TNS) was investigated quantitatively to develop useful host compounds comparing with ${\alpha}\;-\;and\;{\beta}-cyc1odextrins$$({\alpha}-\;and\;{\beta}-CyDs$) in aqueous solution. Benesi-Hildebrand type analysis of the fluorescent intensity showed that the dissociation constants (Kd) of paracyclophane-ANS complexes were $1.55\;{\times}\;10^{-4}M$ for 1,6,20,25-tetraaza[6.1.6.1]paracyclophane(CPM 44) and $1.23\;{\times}\;10^{-4}M$ for 1,7,21,27-tetraaza[7.1.7.1]paracyclophane (CPM 55), and those of paracyclophane-TNS complexes were $6.99\;{\times}\;10^{-6}M$ for CPM 44 and $6.23\;{\times}\;10^{-5}M$ for CPM 55, in 1:1 molar ratio. On the other hand, the Kd values of 1,7,21,27-tetraaza-14,34-dioxa[7.1.7.1]paracyclophane (CPE 55)-ANS, 1,8,22,29-tetraaza-15,36-dioxa[8.1.8.1]paracyclophane (CPE 66)-ANS, CPE 55-TNS, CPE 66-TNS complexes were $1.75\;{\times}\;10^{-3}M$, $3.07\;{\times}\;10^{-3}M$, $3.75\;{\times}\;10^{-3}M$ and $2.15\;{\times}\;10^{-3}M$, respectively. On the contrary, the Kd values of ${\alpha}-CyD-ANS$, ${\beta}-CyD-ANS$, ${\alpha}-CyD-TNS$ and ${\beta}-CyD-TNS$ complexes were found to be $3.98\;{\times}\;10^{-2}M$, $1.05\;{\times}\;10^{-2}M$, $1.38\;{\times}\;10^{-2}M$ and $3.52\;{\times}\;10^{-4}M$, respectively. These results mean that the complexation of CPMs with ANS or TNS is by 5.6-1,975 fold stronger than that for ${\alpha}-or\;{\beta}-CyDs$, and the complex formation of CPEs with ANS or TNS is nearly same as or somewhat stronger than that for ${\alpha}-or\;{\beta}-CyDs$. From the Kd values determined at different temperatures, thermodynamic parameters were calculated and the complexation was found to be a spontaneous exothermic reaction. The effects of pH on Kd values of CPM 44-ANS, and CPM 55-ANS complexes were negligible in the range of pH 1.2-1.8. However, the Kd values of these complexes increased significantly with increasing ionic strength.