• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.869-877
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• 2000

A mechanism of ozonation of simulated soil slurry contaminated by phenanthrene and benzo[a]pyrene has been studied under various conditions. The effects of soil media(BS, S, GB), radical scavenger, ozone input ratio(0.17~0.73mg/min), bicarbonate ion, and humic acid were investigated, BS showed the highest removal efficiency in media tested. The generation of OH-radical via the catalytic decomposition of ozone on active sites of the natural sand was confirmed by OH-radical scavenger experiments. The enhanced removal efficiency by OH-radical was indirectly quantified to be about 22%. As initial concentration of humic acid(as sodium salt) was increased, pseudo first-order rate constant ($k_o$) of phenanthrene was decreased from $1.37{\times}10^{-2}s^{-1}$ to $0.53{\times}10^{-2}s^{-1}$. The amount of ozone required to oxidize 80% of the initial mass of phenanthrene(10mg/kg) and benzo[a]pyrene(10mg/kg) was 67.2mg/kg-soil and 48.0mg/kg-soil, respectively.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.350-357
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• 2014

BACKGROUND: Deicers such as calcium chloride ($CaCl_2$) and sodium chloride (NaCl) in Korea have been commonly used to reduce traffic accidents as well as injuries. However there have been adverse effects of deciders such as pollution of water and soil, and reduced productivity of agriculture as well as forest. This study aimed to investigate biological effects of the deicers against wheat, barley, and spinach. METHODS AND RESULTS: The germination of tested crop seeds exposed to chloride-deicers, $CaCl_2$ and NaCl was significantly reduced at over 3% concentration of chloride-deicers compared to the control. In spraying deicers to the seedlings of the crops, there was no symptom such as inhibition of growth rate or leaf elongation. However the germination of tested crop seeds was affected at 2% concentration of deicers when they were exposed continuously to deicers in soils. The growth of the shoot against $CaCl_2$ and NaCl treatments was very similar in wheat and barley whereas the shoot of spinach was the most susceptible. Based on these results, the sensitivity of the crops to the tested deicers was as follows: NaCl > $CaCl_2$ > mixture ($CaCl_2$ + NaCl). The length of shoots and roots of the seedlings grown in 1% treated soil was decreased. The biomass of all the seedlings decreased 1.5 to 4 times at 1%. CONCLUSION: These results indicate that the effects of salt deicers by inputting into soil against growing tested crops are more severe in germination and growth inhibition as well as biomass decrease.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.1
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• pp.25-30
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• 2006

This experiment was conducted to compare the fresh yield and dry matter yield, and nutritive values of whole crop barley treated with Urea (200 kg/ha, T2) and ammonium sulfate fertilizer as 200 kg/ha (T3), 300 kg/ha (T4) and 400 kg/ha (T5) at the Bae-Ho reclaimed tideland. Korea from 2003 to 2005. Salt contents of soil in the ammonium sulfate plots (T3, T4, T5) were lower than those of T2. The fresh yields of ammonium sulfate plots (T3, T4, T5) were higher than those of T2 as 62% (p>0.05), 41% (p>0.05) and 23% (p<0.05), respectively. The dry matter yield of T3, T4 and T5 (ammonium sulfate) was significantly (p<0.05) higher at 5,080 kg/ha, 4,667 ka/ha, 4,040 kg/ha, respectively. The total digestible nutrients (TDN) yield tends to have a similar result. Crude protein (CP) content was highest in T3 and CP trends to decrease as the level of ammonium sulfate was increased. Total digestible nutrient (TDN) were high in T3 and T4. The sodium content of T3 and T4 were lower than T2. Based on the study, it was more desirable to use ammonium sulfate (200 kg N/ha) rather than Urea as fertilizer on reclaimed land in terms of forage production and nutritive value.

• The Korean Journal of Pharmacology
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• v.18 no.1
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• pp.23-31
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• 1982

1) Experiments were undertaken to elucidate the mechanism which elevates the systemic arterial blood pressure by cadmium (Cd). 2) The mean arterial pressure and peripheral resistance of central ear artery in Cd-poisoned rabbit were significantly increased in comparison with those in control. 3) The vascular pressure response to electrical stimulation in Cd-poisoned group was less than that in control. However, in the former group it showed the supersensitivity to norepinephrine. 4) The response to electrical stimulation was diminished by sodium arachidonate in the ear artery, on the contrary, it was rather enhanced in the vessel of Cd-poisoned group. The responses in both groups were reduced by pretreatment with either $PGE_2\;or\;PGF_{2{\alpha}}$. 5) The response to electrical stimulation was not affected in control, but enhanced in Cd-poisoned group by pretreatment with indomethacin. 6) When the ear artery of control group was perfused with physiological salt solution (PSS) the response to electrical stimulation was not changed by indomethacin, it was much enhanced without affecting on the response to norepinephrine when $K^+-free\;PSS$, was used. These results demonstrate the evidence that the alteration of regulatory mechanism on the vessels was causally related to the elevation of arterial pressure and the increase in peripheral resistance in Cd-poisoned rabbits.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.2
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• pp.113-118
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• 2005

This experiment was conducted to compare the dry matter yields and fled values of winter forage crops using too cultivars of Barley, Rye md Italia ryegrass at the Dae-Ho reclaimed tideland, Korea from 2002 to 2004 2rowing season. Soil salt contents of three forage crops showed highest at sowing time, respectively and after wintering continuously lowed till harvest time. The dry matter yield was 6,668.8, 4,455.6 md 2,591.2 kg / ha, respectively, for Italian ryegrass, Barley and Rye. The highest Crude protein(CP) content was recorded in Italian ryegrass. Acid detergent fiber(ADF) contents were lowed in row with Barley, Italian ryegrass and Rye. Sodium contents in plant tissue were recorded high in line with Barley, Italian ryegrass and Rye. results mentions above suggest Italian ryegrass is suitable winter forage crops for cultivation on reclaimed tideland in view of the good emergence, forage production and its feed value.

• Journal of the Korean Chemical Society
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• v.54 no.3
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• pp.269-274
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• 2010

The solubility and the physicochemical property (refractive index) in the NaCl-$CaCl_2$-$H_2O$ and KCl-$CaCl_2$-$H_2O$ systems were determined at $50^{\circ}C$ and the phase diagrams and the diagrams of physicochemical property vs composition were plotted. One invariant point, two univariant curves, and two crystallization zones, corresponding to sodium Chloride (or potassium chloride), dihydrate ($CaCl_2{\cdot}2H_2O$) showed up in the phase diagrams of the ternary systems. The mixing parameters ${\theta}_{M,Ca}$ and ${\Psi}_{M,Ca,Cl}$ (M = Na or K) and equilibrium constant $K_{sp}$ were evaluated in NaCl-$CaCl_2-H_2O$ and KCl-$CaCl_2-H_2O$ systems by least-squares optimization procedure, in which the single-salt Pitzer parameters of NaCl, KCl and $CaCl_2$ ${\beta}^{(0)}$, ${\beta}^{(1)}$, ${\beta}^{(2)}$ and $C^{\Phi}$ were directly calculated from the literature. The results obtained were in good agreement with the experimental data.

• Applied Chemistry for Engineering
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• v.8 no.4
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• pp.568-574
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• 1997

The effect of microencapsulation of maetal hydride (MH) with copper on the electrode performance of a Ni/MH battery has been investigated. The MH electrodes were prepared with a combination of cold press and paste methods. The discharge capacity of the electrode increased with an addition of small amounts if CMC into the electrode, but decreased when heat-treated in an oxygen-free nitrogen flow. The capacity of a Cu-coated $LaNi_5$ electrode was higher than that of LaNi5electrode. The discharge capacity of the electrode prepared with Cu-coated $LaNi_5$ increased with the increase of copper content in the electrode. It is considered that the increase of copper content enhanced the current density on the electrode surface, leading to the increase of the discharge capacity The MH electrode coated by an acidic electroless plating method showed much higher discharge capacity than that using an alkaline electroless plating method. The discharge capacity of the $LaNi_{4.5}Al_{0.5}$ electrode was higher than that of the $LaNi_5$ electrode. Also, the effect of microencapsulation on the deactivation of $LaNi_5$ was studied using an absorption-desorption cycle in CO-containing hydrogen.

• Korean Chemical Engineering Research
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• v.46 no.2
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• pp.330-339
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• 2008

Effect of additives such as NP series nonionic surfactant and cosurfactant on AgCl nanoparticles was investigated where nanoparticles were prepared using two different types of water-in-oil (W/O) microemulsions containing silver nitrate and sodium chloride, respectively. Phase behavior experiments showed that the region of one phase W/O microemulsion was found to be broadened with an increase in the ethylene oxide length of a nonionic surfactant mainly due to an increase in hydrophilic nature of a surfactant. Photomicrographs obtained by transmission electron microscopy indicated that an increase in ethylene oxide length of a nonionic surfactant results in both increases in particle size and size distribution. Phase behavior experiments for the systems containing AOT surfactant, isooctane and aqueous solution of an inorganic salt showed that addition of a cosurfactant caused a shrinkage in phase region of one phase W/O microemulsion, especially water contents contained in W/O microemulsion with an increase in the chain length or the concentration of a cosurfactant used. Photomicrographs obtained by transmission electron microscopy indicated that characteristics of AgCl nanoparticles produced were dependent both on the radius of spontaneous curvature and film rigidity of a microemulsion.

• Journal of the Korean GEO-environmental Society
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• v.19 no.10
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• pp.21-26
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• 2018

Soil-water characteristic curve, which is called soil retention curve, is required to explore water flows in unsaturated soils, relative permeability of water in multi-phase fluids flow, and change to stiffness and volume of soils. Thus, the understanding of soil-water characteristic curves of soils help us explore the behavior of soils inclduing fluids. Biopolymers are environmental-friendly materials, which can be completely degraded by microbes and have been believed not to affect the nature. Thus, various biopolymers such as deacetylated power, polyethylene oxide, xanthan gum, alginic acid sodium salt, and polyacrylic acid have been studies for the application to soil remediation, soil improvement, and enhanced oil recovery. PAA (polyacrylic acid) is one of biopolymers, which have shown a great effect in enhanced oil recovery as well as soil remediation because of the improvement of water-flood performance by mobility control. The study on soil-water characteristic curves of sandy soils containing PAA (polyacrylic acid) has been conducted through experimentations and theoretical models. The results show that both capillary entry pressure and residual water saturation dramatically increase according to the increased concentration of PAA (polyacrylic acid). Also, soil-water characteristic curves by theoretical models are quite well consistent with the results by experimental studies. Thus, soil-water characteristic curves of sandy soils containing biopolymers such as PAA (polyacrylic acid) can be estimated using fitting parameters for the theoretical model.

• Journal of Life Science
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• v.19 no.10
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• pp.1424-1431
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• 2009

Shrimp Jeot-Gal is a popular traditional Korean fermented seafood and has been used for seasoning. We isolated a bacterium showing strong extra-cellular fibrinolysis and chitinase activity from shrimp Jeot-Gal and the strain was designated SC082. SC082 was identified as Bacillus licheniformis by 16S rRNA sequence homology search. B. licheniformis SC082 exhibited optimum temperature, pH, and salt concentration at $37^{\circ}C$, pH 7.0, and 6%, respectively. Substrate specificity of the culture supernatant from B. licheniformis SC082 was detected in fibrin, skim milk, and chitin plate. The fibrinolytic activity was highly maintained up to $50^{\circ}C$ at a pH of 7.0 for 3 hr and was stable up to pH 9.0 at $37^{\circ}C$ for 3 hr. The chitinase activity was remarkably induced by addition of 1.0% colloidal chitin and the pH and temperature optima of the enzyme were 5.0 and $45^{\circ}C$, respectively. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis and zymogram analysis, this strain produced three fibrinolytic isozymes and two chitinase isozymes. The approximate molecular weights of the putative fibrinolytic enzymes were 23.0, 62.0, and 72.0 kDa and those of the chitinases were 62.0 and 55.0 kDa, respectively. The antioxidant activity of SC082 was also measured by using 2,2-diphenyl-l-picryl-hydrazyl (DPPH) free radical. The DPPH radical scavenging was slightly increased in a dose-dependent manner.