• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.349-355
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• 2008

The causes of salt accumulation in soils of plastic film houses nearby Sumjin river estuary in Mokdo-ri($127^{\circ}46'E\;35^{\circ}1'N$), Hadong, Gyeongnam, Korea were investigated in 2006. With chemical properties soils and water analyzed and fertilization status monitored, the study showed that mean salt concentration of soil was much higher at EC $4.3\;dS\;m^{-1}$ than the Korean average (EC $2.9\;dS\;m^{-1}$) in 2000s for plastic film house's soil with exchangeable Na $0.8\;cmol^+\;kg^{-1}$ and water-soluble Cl $232\;mg\;kg^{-1}$, and then might result to salt damage in sensitive crop plants. Salt concentration of ground water used as main irrigation water source contained very high EC with corresponding value of $2.6\;dS\;m^{-1}$. Particularly, increase of EC value was directly proportional with the increased pumping of ground water used as a water-covering system in order to protect the temperature inside plastic film houses from the early winter season. High Na and Cl portion of ions in water might had contributed to the specific ion damage in the crops. Secondly, heavy inputs of chemicals and composts significantly increased the accumulated salts in soil. Conclusively, salt accumulation might had been accelerated by use of salted-groundwater irrigation and heavy fertilization rate. To minimize this problem, ensuring good quality of irrigation water is essential as well as reducing fertilization level.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.295-302
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• 2006

The present study addressed the efficacy of nanosized silica-silver for controlling plant pathogenic microorganisms. The nanosized silica-silver consisted of nano-silver combined with silica molecules and water soluble polymer, prepared by exposing a solution including silver salt, silicate and water soluble polymer to radioactive rays. The nanosized silica-silver showed antifungal activity against the tested phytopathogenic fungi at 3.0 ppm with varied degrees. In contrast, a number of beneficial bacteria or plant pathogenic bacteria were not significantly affected at 10 ppm level but completely inhibited by 100 ppm of nanosized silicasilver. Among the tested plant pathogenic fungi, the new product effectively controlled powdery mildews of pumpkin at 0.3 ppm in both field and greenhouse tests. The pathogens disappeared from the infected leaves 3 days after spray and the plants remained healthy thereafter. Our results suggested that the product developed in this study was effective in controlling various plant fungal diseases.

• Journal of Radiation Industry
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• v.2 no.3
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• pp.149-154
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• 2008

The present study described an antimicrobial spray composition comprising nanosized silica-silver particles, in which nano-silver is bound to silica molecules and a water-soluble polymer, the nanosized silica-silver particles prepared by irradiating a solution comprising a silver salt, silicate and the water-soluble polymer with radiation rays. According to a surfactant addition, the compositions were not turbid and were colorless. Also samples (cotton fabrics and wallpaper) were treated with the compositions also did not cause any stains even after drying under sunshine and at $80^{\circ}C$. Our results suggested that the spray formulation product was of practical use to control indoor fungi.

• Bulletin of the Korean Chemical Society
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• v.22 no.11
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• pp.1243-1247
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• 2001

The water-soluble poly(aminoaryloxy-methylamino phosphazene) has been synthesized and investigated as a polymeric carrier species for the covalent attachment of biologically active agents. The cyclic trimeric model systems were utilized for the synthesis of polymeric analogues containing bioactive side groups. The sodium salt of 4-acetamidophenol was first allowed to react with (NPCl2)3 or (NPCl2)n and was then treated with excess methylamine to yield derivatives of type [NP(NHCH3)x(OArNHCOCH3)y]3 or [NP(NHCH3)x(OArNHCOCH3)y]n. The 4-acetamido groups were then hydrolyzed to 4-aminophenoxy units with potassium tert-butoxide. Coupling reactions between amino group and N-acetylglycine was accomplished with the use of dicyclohexylcarbodiimide. Their properties and structural characterization are discussed.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.3
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• pp.79-89
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• 2017

Changes in pH, EC and water soluble cation and anion of the bed material in the rearing box of earthworms were investigated while sewage sludges or night soil sludge were cumulatively supplied to the 15 grams of initial earthworm population in the rearing box. Initial biochemical properties of sludges such as pH, EC, V.S. and water content were at the edible levels for earthworm. However, as the cumulative amount of sludges supplied to the earthworms were increased, pH of bed material in the rearing box was lowered and EC was increased, which meant that salt contents of bed material in the rearing box had been accumulated. Water soluble cations and anions were also accumulated in the bed material of the rearing box. Accumulation rates of ${NO_3}^-$ were especially prominent. Consequently, feeding rates of earthworm populations were reduced to nearly zero and earthworm populations finally died.

• Journal of the Korean Society for Heat Treatment
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• v.15 no.5
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• pp.213-218
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• 2002

In order to develop the economic and environmental water-soluble black coloring agent, some adequate chemical mixtures were mixed and this solution was applied to coat quenched and tempered 51B20 steel bolt. Some basic properties of the solution and characteristics of the coated film in addition to the corrosion resistance were investigated. The developed 100 kg of water-soluble black coloring agent solution was a chemical mixture consisted of 10 kg of aqueous coloring agent, 40 kg of surface active agent, 0.3 kg of anti-foam agent and $50{\ell}$ of water. The coated film of the bolt was composed of hard layer of about $2{\mu}m$ and the disbondable soft layer of about $4{\mu}m$ above the hard layer. Many surface active agents peaks and a few hydrophilic peaks were observed in the coated film. Surface roughness value of the coated bolt was lower than that of the non-coated bolt. Corrosion resistance of the coated bolt considerably improved and also relatively showed a good polarization resistance at test condition of $40^{\circ}C$ colorizing temperature and 5% the solution concentration in 3% NaCl anodic polarization test. Initial appearance time of the surface rust was greatly retarded owing to the coated film in salt spray test.

• Journal of the Korean Society of Food Culture
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• v.6 no.1
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• pp.61-69
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• 1991

Brewing method and quality of 10 sample of traditional Dungge-Jang in Kyungsang-Do area were investigated. In order to improve the taste of Dungge-Jang, some amount of boiled bean was added in the Dungge-Jang at early stage of fermentation. The level of amino nitrogen turned out to be low while that of water soluble protein and salt soluble protein was high. Glutamic acid, aspartic acid and proline were the major amino acid in water and salt soluble protein in traditional Dungge-Jang in Kyungsang-Do area. The content of total sugar and free reducing sugar were found to be considerably high, and among the free sugar, glucose was the highest$(2.16{\sim}4.02\;mg/ml)$, followed by maltose and maltotriose. Activities of acid protease and liquefying amylase were $0.13{\sim}1.36$ unit per milliliter and $10.18{\sim}15.19D^{40o}_{30}$ respectively. Result of sensory evaluation showed that the good Dungge-Jang turned out to have well harmonized taste of flavor, sweetness and sourness while the color looked slightly dark and yellow.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.135-142
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• 2012

Exchangeable cations are often overestimated especially in salt-affected soils due to the presence of high levels of soluble ions in soil solution. Thus, quantitative analysis of the soil exchangeable cation based on ammonium acetate extraction method {(Exch. Cation)$_{total}$} requires additional process to remove the free ions (pre-washing) in soil with distilled water or alcohol {(Exch. Cation)$_{pw}$} or subtraction of the soluble ion contents from the total exchangeable cations {(Exch. Cation)$_{ref}$}. In this research, we compared the three different methods for the determination of exchangeable cations in soils affected by different types of salt accumulation such as the soils from upland, plastic film house, and reclaimed tidal land. In upland soils, non-saline and non-sodic soils, the regular ammonium acetate extraction method did not have any problem to determine the content of exchangeable cations without any additional process such as the pre-washing method or the subtraction method. However, the contents of exchangeable cations in the salt-affected soils might be determined better with the pre-washing method for the plastic film house soils and with the subtraction method for the reclaimed tidal land soils containing high Na.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.447-452
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• 1988

In order to study effect of freezing rates on the quality changes such as pH, TBA value, free fatty acids and protein extractability, cylindrical chopped beef logs with 10cm of diameter and 10cm of height were frozen at three freezing rates(0.97cm/hr, 2.05cm/hr, 3.71cm/hr)using air blast freezer. Physicochemical changes of frozen meat were investigated during forzen storage at $-20^{\circ}C$ for 16weeks. Results on pH change showed $0.1{\sim}0.2unit$ increase at the 16th week of the frozen storage and the change was smaller with the increasing freezing rates. Free fatty acids content and TBA value also were increased during forzen storage, but they were minimal at 3.71cm/hr freezing rate. Correlation coefficient between TBA value and free fatty acids content were highly significant(r=0.804). After 16weeks of storage, extractibilities of salt soluble protein were decreased by 17.7%, 6.1% and 1.6% at freezing rates of 0.97, 2.05 and 3.71cm/hr, respectively. On the other hand, extractabilities of water soluble protein were decreased by 26.0%, 21.2% and 18.5%, respectively. The effect of freezing rates on the protein extractability appeared to be greater in salt soluble protein than in water soluble protein, but freezing denaturation was more rapid in water soluble protein.

• Journal of Conservation Science
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• v.34 no.4
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• pp.259-271
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• 2018

Outdoor copper alloy is exposed to the atmospheric environment, accelerating corrosion progress compared with indoor copper alloy. In order to prevent corrosion, the outdoor copper alloy is coated with wax to block external corrosion factors. However, corrosion of the inside of the coating film is highly likely to continue without the internal corrosion prevention treatment. B.T.A, which is used as a copper alloy water-soluble corrosion inhibitor, has a high possibility of being harmful to the human body and is mainly used to treat excavated artifacts. This study had selected the water-soluble corrosion inhibitor, which was easier to use than the existing wax and B.T.A being used in corrosion inhibition treatment for outdoor copper alloy. A comparative study was conducted on B.T.A, which is a water-soluble corrosion inhibitor used on excavated artifacts, and $VCI^{(R)}$, $Rus^{(R)}$, and L-cys, an amino acid corrosion inhibitor, used for tin bronze test pieces. The experimental method was conducted for a certain period of time with the salt, acid, and air pollution affecting the corrosion of outdoor copper alloy. Based on experiment results, it was concluded that the best water - soluble copper alloy corrosion inhibitor in the atmospheric environment is $VCI^{(R)}$. and it could be considered to be applied in replacement of B.T.A due to its low harmfulness. In addition, $VCI^{(R)}$ is judged to serve as a corrosion inhibitor for outdoor copper alloy because it showed the best result even in the outdoor exposure test which is a real atmospheric environment.