• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.375-378
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• 1991

Bangah (Agastache rugosa O. Kuntze), one of the wild plant grown in Korea and used for deodorizing some of the fish foods because it's strong and unique flavor, was determined for chemical composition in leaf, flower and stem. The highest protein content of 14.7% was found in leaf and lipids was in the range of $5.25{\sim}7.74%$. Total sugar content in leaf and flower were 27.53% and 14.86%, reducing sugar content were 11.80% and 2.75%, respectively. Fifteen fatty acids in bangah were identified and the major fatty acids were linolenic, palmitic, lauric and linoleic acids. Seventeen total amino acids were determined in leaf and flower. Glutamic acid, aspartic acid and leucine were high in each portion. The major free amino acids were histidine, serine, proline and glutamic acid. Most of minerals were high in leaf and flower than those in stem of bangah except for Ca and Fe. Especially K was higher in leaf and flower than stem by 4 times.

• Korean Journal of Food Science and Technology
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• v.33 no.5
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• pp.534-539
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• 2001

To utilize oyster cannery processing waste water effectively, this study was carried out to prepare instant powdered soup using oyster wash water. Instant powdered soup from oyster hot-water extracts (HWE) was prepared by mixing oyster spray-dried hot-water extracts (15 g) with table salt (5 g), cream powder (19 g), milk replacer (12 g), wheat flour (20 g), corn flour (15 g), starch (5 g), glucose (7.5 g) and onion powder (1.5 g). In preparing instant powdered soup from oyster wash water (OWW), powder from oyster spray-dried wash water instead of the spray-dried hot water extracts, was added and other additives were added in proportion to those in the HWE. The OWW consists mainly of carbohydrates (71.1%). It was not different from the instant powdered soup from hot-water extracts. The volatile basic nitrogen, vaible cell counts, coliform group of instant powdered soup from oyster wash water contains 29.4 mg/100g, $4.6{\times}10^4\;CFU/g$, <18 MPN/100g, respectively and its water activity has 0.246. So it was a hygienically safe and conservable instant food. The main fatty acid of OWW was 16 : 0 and 18 : 1n-9. Its chemical score of protein was 59.4% and its main inorganic matter was iron. According to a sensory evaluation, in contrast to the HWE, the OWW had a slightly lower aroma but better taste. It was concluded from the above chemical and sensual evaluation that the oyster wash water can be used as a flavor enhancer for instant powdered soup.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.3
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• pp.171-177
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• 2010

As concrete structures are exposed to chemical substances, damaged from salt, or progressed to the neutralization, the surface damage of the structures is generated timely fashion, resulting shortened service life. Especially, the sulfate erosion causes rapid surface defects, and the steel skeleton becomes corroded due to the water infiltration, generating stability deterioration of the concrete structure. In this study, the physical characteristics of the acid-resistant mortar with aluminosilicates was investigated in order to resolve problems of the acid resistance, one of the most serious problems of the cement type repair material. As the result of the experiment, the test specimen turned to exhibit almost equivalent physical characteristics with those of concrete sectional repair materials in terms of compressive and bending strengths. As both the cement sectional repair material and the test specimen were immerged in sulfuric acid solution to examine weight changes, the test specimens exhibited only 4% loss of their weights while the cement sectional repair materials reached at the level of 80% or above, proving the excellence acid resistant characteristics of the test specimens. Consequently, the physical characteristics of acid resistant mortar with aluminosilicates were revealed to be superior than those of concrete sectional repair materials. It can be utilized as a sectional repair material where the acidic erosion is anticipated.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.573-581
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• 1999

The study was carried out to determine the toxicity of cyanide on the hemochemical changes of Israel carp, Cyprinus carpio reared under a continuous-flow system for 5 weeks, The carps exposed to cyanide concentation oyer 151 $\mu$g/$\ell$ started to decrease significantly in red blood cell count, hemoglobin concentration and hematocrit value at week 4. However a significant elevation of MCH and MCV was noticed a week later, at week 5 at cyanide concentration 289 $\mu$g/$\ell$. The low concentration of serum calcium was observed at the last week of the experiment in cyanide concentration 151 $\mu$g/$\ell$, while serum magnesium concentration initiated to increase from the 4th week at the cyanide concentration 289 $\mu$g/$\ell$. Serum -total protein, albumin and glucose concentrations decreased significantly after 4th week at the concentration over 151 $\mu$g/$\ell$. A significant increment of GOT, GPT and LDH activities in the carp serum was noticed after 3rd week at cyanide concentrations over 151$\mu$g/$\ell$ without typical changes of Al-P and amylase, These results indicate that carps can be affected by cyanide in terms of red blood cell count, hemoglobin concentration and hematocrit value in blood, calcium and magnesium concentration, GOT, GPT and LDH activities in serum when they were exposed to the cyanide concentrations 151 $\mu$g/$\ell$ or higher.

• Food Science and Preservation
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• v.18 no.3
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• pp.341-348
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• 2011

The nutritional components and antioxidative activities of jujube fruit and leaf were investigated and analyzed to provide basic data for functional food materialization and processing. The nitrogen-free extract contents of the fruit and leaf were 71.92% and 41.51%, respectively. The mineral components of the fruit and leaf were rich in Ca (72.14 and 3,252.09 mg/100 g), K (899.82 and 1,708.12 mg/100 g), and P (172.11 and 286.28 mg/100 g), respectively. The major free sugars of the fruit were glucose (13.01 %) and fructose (7.35%); and of the leaf, sucrose (3.94%) and fructose (0.75%). The ascorbic acid contents were higher in fruit (135.73 mg/100 g) than in the leaf (100.43 mg/100 g). The analysis of the component amino acid showed a relatively high ratio of glutamic acid, aspartic acid, proline, and essential amino acids of leucine, but a low methionine and cystine content. The ABTS and FRAP assays indicated that the butanol fraction of the leaf was a more potent radical scavenger and reducing agent than the other five solvent fractions. The butanol fraction of the leaf also presented inhibitory effects against lipid peroxidation in a dose-dependent manner. Therefore, this study verified that the butanol fraction of the leaf has strong antioxidative activities that are correlated with its high level of phenolics, particularly rutin and quercitrin. These phenolics of jujube leaf can be utilized as effective and safe functional food substances, i.e., natural antioxidants.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.17-25
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• 2001

High salt content in food waste limit use as the potential source of compost. Since sodium chloride content should be lower than one percent to meet requirement for agricultural use of compost, we attempted use of three kinds of co-composting material for food wastes compost, which were fermented, dried, and fresh types of amendments which included pig manure, sawdust and puffed rice hull. Food wastes were composted well and stabilized after around the 40th days of composting. Little difference were found between composts amended sawdust and puffed rice hull. The result indicated that puffed rice hull could be used as a good alternative of sawdust. Because sawdust or puffed rice hull were mixed as amendments to control water contents and to dilute high NaCl content of compost material, the C/N ratios of the final products were significantly high over 40. However, NaCl contents of final products were dropped to less than percent on the fresh weight basis by mixing food wastes and the above amendments with the optimum rates.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.6
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• pp.476-481
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• 2007

There was no difference between eco-friendly and conventional cultivated soils in the chemical properties. But $Av.P_2O_5$ contents in the eco-friendly cultivated soils were slightly higher than that of conventional cultivated soils. In the conventional cultivated soils, the coefficient of correlation between spore density and soil chemical properties such as pH, EC, OM, $Av.P_2O_5$, K${\surd}$(Ca+Mg) and CEC was $-0.48^*$, -0.05, $0.48^*$, -0.12, -0.13, 0.31 respectively. But, in the eco-friendly cultivated soils was $-0.68^*$, $0.69^*$, $0.96^{**}$, $0.75^*$, $0.63^*$, $0.92^{**}$ respectively. The spore density was 140 spores $30g^{-1}$ in the eco-friendly cultivated soils and 60 spores $30g^{-1}$ in the conventional cultivated soils. Infection ratio of intercellular hypha was higher than that of arbuscular and vesicular among the fungi structures within the root. Suncheon and Cheonan as eco-friendly cultivated soil were higher than GimJe and NamWon in infection ratio.

• Journal of Marine Life Science
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• v.5 no.1
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• pp.25-33
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• 2020

The Asan Bay, which has semi-diurnal tide with macro-tidal range, is affected by both freshwater discharge from the sluice gates in the sea dikes and tidal seawater inputs from the Yellow sea. Understanding water quality change in response to tides is important since tides can impact the short-term variations in physical and chemical water properties as well as the response of biological properties. The diel variations in water quality were seasonally investigated at 2 hour intervals from a fixed station in the Asan Bay. In the results, water temperature and salinity consistently fluctuated in phase or out of phase with tidal height. Especially salinity was positively correlated with tidal height. The concentrations of total suspended solids were higher in the bottom water than in the surface and fluctuated greatly over the tidal cycle recording higher values at low tide than at high tide. Nitrite+nitrate levels also fluctuated out of phase with tidal height and correlated negatively with tidal height. Other nutrients also showed a similar pattern. The pattern was distinct in July when freshwater was discharged before the field sampling. The concentrations of organic materials, total nitrogen and total phosphorus greatly fluctuated over the tidal cycle and were generally out of phase with tidal height. Most materials except particulate organic forms were correlated with salinity indicating that freshwater inputs were sources for the materials similarly to the dissolved inorganic nutrients. The results suggest that water quality (except dissolved oxygen and pH) and nutrients including organic materials was largely affected by tides in the Asan Bay.

• Korean Journal of Plant Resources
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• v.34 no.4
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• pp.249-256
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• 2021

Napa cabbage (Brassica campestris var. Pekinensis) is the main material of Kimchi so that important crop in South Korea. There are two typical napa cabbage cropping systems in the alpine area. One is cultivating napa cabbage annually while another is cultivating napa cabbage and potato biennially. In this research, we evaluated soil physiochemical properties, yield, and mineral contents of napa cabbage depending on two cropping systems. As a result, organic matter, available P₂O₅, exchangeable K⁺ was decreased after six-years of cultivation on both cropping systems. However, soil pH was only decreased in a continuous napa cabbage cropping system. Soil porosity is also decreased in both cropping systems on topsoil while is increased in rotation with potato on subsoil. The rotation system showed a significantly higher yield with a higher value of leaf and napa cabbage size than the continuous cropping system. Total nitrogen, Ca²⁺, and Ma²⁺ were increased and total carbon and phosphate decreased in both cropping systems after six-years. Especially, total nitrogen and Mg²⁺ were significantly higher in the continuous system while Ca²⁺ was higher in the rotation system. In conclusion, the cropping system influences soil physiochemical properties and plant production in an agricultural field.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.255-260
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• 2011

$NH_4{^+}-{\beta}^{{\prime}{\prime}}$-alumina which is expected to an inorganic solid electrolyte of high temperature polymer electrolyte membrane fuel cells (PEMFC) was prepared by ion-exchange reaction of $K^{+}-{\beta}^{{\prime}{\prime}}$-alumina pellet with $NH_4NO_3$ aqueous solution and molten $NH_4NO_3$ salts as an ion-exchange medium in the autoclave and the heating mentle reaction. In the autoclave reaction, the concentrations of $NH_4NO_3$ solution was chosen at 5 and 10 M. Each ion-exchange reaction was carried out at 130, 150, 170, and $200^{\circ}C$ for 2, 4, 6 and 8 h. In the heating mentle reaction, ion-exchange was performed at $200^{\circ}C$ for 2, 4, 6 and 8 h with molten $NH_4NO_3$ salts. In order to determine the effect of reaction times, each ion-exchange reaction was repeated 3 times. The phase stability and the ion-exchange rate of $NH_4{^+}-{\beta}^{{\prime}{\prime}}$-alumina were analyzed by XRD and ICP.