• Applied Chemistry for Engineering
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• v.5 no.5
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• pp.764-771
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• 1994

Electrochemical synthesis of conductive polypyrrole films was carried out in nucleophilic solvent containing p-toluenesulfonic acid or bezensulfonic acid as supporting electrolyte and dopant. Also characteristics of degradation and improvement of mechanical properties were studied. The conductivity, tensile strength and elongation of the films obtained in dimethyformamide/p-toluenesulfonic acid had the highest value of 10-40S/cm, $25N/mm^2$ and 10%, respectively. The optimum condition of electrochemical synthesis was $2mA/cm^2$ for constant current method and 0.9V for constant potential method containing 0.5M pyrrole and 0.5M p-TSA. The obtained films showed good stability in air and electrode characteristics of secondary battery by reversibility in doping and undoping. The degradation process was 1st order reaction at various temeprature. The activation energy and rate constant of degradation reaction were $1.01JK^{-1}mol^{-1}$ and $3.1{\times}10^{-7}min^{-1}$ respectively at $25^{\circ}C$. For the improvement of mechanical properties, composition of polypyrrole films with various host polymer were investigated and increase of tensile strength and elongation was confirmed.

• Research in Plant Disease
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• v.23 no.3
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• pp.256-261
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• 2017

The effects of insecticide and fungicide treatment were investigated to reduce mycotoxin contamination of corn (Zea mays L.) seeds. Deoxynivalenol and zearalenone contents were reduced in the treated seeds, but aflatoxin, ochratoxin A, fumonisin, and T-2 toxin were not effective by chemical treatments. The chemical treatment did not affect the growth of saprophyte, but inhibited the pathogenic fungi such as Fusarium verticillioides, F. graminearum and F. equiseti. Myotoxin contents at different harvesting time were compared. As the harvest time was delayed, both levels of deoxynivalenol and zearalenone and frequency of Fusarium spp. increased. However, the major nutrient contents of corn seeds were not affected by harvesting period. These results show that chemical treatments are necessary to reduce the fungal contamination of corn and harvest without delay is important as well.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.716-721
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• 2010

LCA (Life Cycle Assessment) carried out to estimate carbon footprint and to establish of LCI (Life Cycle Inventory) database of rice production system. The results of collecting data for establishing LCI D/B showed that organic fertilizer and chemical fertilizer input to 4.29E-01 kg $kg^{-1}$ rice and 2.30E-01 kg $kg^{-1}$ rice for rice cultivation. It was the highest value among input for rice cultivation. And direct field emission was 3.23E-02 kg $kg^{-1}$ during rice cropping. The results of LCI analysis focussed on greenhouse gas (GHG) was showed that carbon footprint was 8.70E-01 kg $CO_2$-eq. $kg^{-1}$ rice. Especially for 80% of $CO_2$ in the GHG and 7.02E-01 kg of its $CO_2$-eq. $kg^{-1}$ rice. Of the GHG emission $CH_4$, and $N_2O$ were estimated to be 13% and 5%, respectively. With LCIA (Life Cycle Impact Assessment) for rice cultivation system, it was observed that fertilizer process might be contributed to approximately 80% of GWP (global warming potential).

• Journal of Applied Biological Chemistry
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• v.51 no.1
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• pp.20-27
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• 2008

The contents of lignan, protein, and oil of nine Sesamum indicum cultivars were analyzed. To determine the lignan contents, sesamin 1 and sesamolin 2 were isolated from the ethylacetate extracts of the Suwon cultivar, and the structures were fully characterized by spectral and physical methods. The seeds of nine cultivars were screened for two lignans, which were determined by HPLC using a $C_{18}$ reversed phase column coupled with a photodiode array detector. Suwon cultivar showed the highest concentration (1: $6.24{\pm}0.04$ and 2: $3.58{\pm}0.01\;mg/g$), whereas Soonheuk displayed the lowest (1: $0.91{\pm}0.01$ and 2: $0.73{\pm}0.01\;mg/g$). The average content ratio of sesamin 1 (3.64 mg/g) was significantly higher than that of sesamolin 2 (2.57 mg/g). The protein content ranged from $21.52{\pm}0.35$ to $31.22{\pm}0.25%$, Suwon containing the highest level and Soonheuk had the lowest. Kwangbaek showed the highest oil level ($49.84{\pm}0.40%$), while Soonheuk exhibited the lowest ($42.52{\pm}0.05%$). Sesamin 1 exhibited a stronger radical-scavenging activity in the ABTS ($IC_{50}:\;63.2{\pm}2.4\;{\mu}M$) than its DPPH radical-scavenging activity ($IC_{50}>200\;{\mu}M$). These results lead to the conclusion that lignan content is affected by protein and oil contents. Concentration of the chemical components in the cultivars could be a key factor in the selection process of a high quality species.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.4
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• pp.318-324
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• 2017

Lime bordeaux mixture (LBM) and lime sulfur mixture (LSM) are representative environmental friendly organic materials for prevention of insect pests in South Korea. Recently, those have been widely used as an alternative for chemical pesticides in eco-friendly farms. However, South Korea has not established even recommendation of LBM and LSM considering the stability of heavy metals in soil. The aim of this study was to evaluate the accumulation of hazardous heavy metals in soil and plant with long-term application of LBM and LSM. Firstly, we investigated the amount of LBM and LSM used per year in several eco-friendly farms to determine a standard application rate of both materials. The pepper plant was grown on the pot in greenhouse for 14 weeks. Both materials were applied at 0, 1, 3, and 9 times of standard application rates (2.56 and $1.28L\;ha^{-1}$ of LBM and LSM per year, respectively). Dry matter yield of pepper and heavy metals (As, Cd, Cu, Hg, Ni, Pb, and Zn) concentration in soil and pepper plant were measured after 14 weeks. Yield of pepper plant did not significantly chang with up to application rate of 1 times, thereafter it markedly decreased with more than 3 times. With increasing LBM and LSM application, the concentration of Cu and Zn in soil significantly increased. Especially, Zn concentration in pepper significantly increased with increasing application rates of both materials. This might resulted in significant decrease in dry matter yield of pepper. The concentrations of those heavy metals in soil did not exceed safety levels ($150mg\;kg^{-1}$ for Cu and $300mg\;kg^{-1}$ for Zn) established by the Korean Soil Environmental Conservation Act as well as concentration of heavy metals in pepper plant by Korean Ministry of Food and Drug Safety. However, particular attention should be paid for heavy metal safety and crop productivity when using LBM and LSM in the organic farm.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.1
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• pp.51-56
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• 1999

$TiO_2$ thin films were spin coated on commercial Nickel-Silver with 2%Ti-naphthanate toluene solution by sol-gel process. The thin films were heat-treated at $500^{\circ}C$ for 2min and then decorative-protective coating was obtained. The conditions for gold colored coating, and the morphology, microstructure and color of the coating surface were have been characterized by Optical microscope, Photospectrometer and XRD. The heating temperature of colored-$TiO_2$ coating was $500^{\circ}C$ and was preferable. The average thickness of 1 time coating was $0.24{\mu}m$ and the total thickness increased linearly as a function of the coating time. The color of amorphous colored-$TiO_2$ coating was changed from gold to dark redish gold with coating time. 'L' as lightness and 'b' were decreased to red, but 'a' was decreased to blue after increase with coating time.

• Nutrition Research and Practice
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• v.14 no.3
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• pp.230-241
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• 2020

BACKGROUND/OBJECTIVES: Inadequate nutrition in infants and young children affects physical growth and neurocognitive development. Therefore, early nutritional intervention is important to promote catch-up growth in young children with faltering growth. The aim of this study was to evaluate the effect of nutritional supplementation with a pediatric concentrated and balanced nutritional supplement formula on promoting growth and improving nutritional status in children with nonorganic faltering growth. SUBJECTS/METHODS: Children aged 12-36 months whose body weight-for-age was < 5^th percentile on the Korean Growth Charts were enrolled. Children born premature or having organic diseases were excluded. Children were instructed to consume 400 mL of formula per day in addition to their regular diet for 6 months. Pediatricians and dietitians educated the parents and examined the subjects every 2 months. Anthropometric parameters were measured at baseline and at 2, 4, and 6 months, and laboratory tests were done at baseline and 6 months. The good consumption group included children who consumed ≥ 60% of the recommended dose of formula. RESULTS: Total 82 children completed the 6-month intervention. At baseline, there were no significant differences in all variables between the good consumption and poor consumption groups. Weight and weight z-scores were significantly improved in the good consumption group compared to the poor consumption group at the end of the intervention (P = 0.009, respectively). The good consumption group showed a significant trend for gaining weight (P < 0.05) and weight z-score (P < 0.05) compared to the poor consumption group during 6 months of formula intake. The concentration of blood urea nitrogen was significantly increased in the good consumption group (P = 0.001). CONCLUSIONS: Nutritional supplementation with a concentrated and balanced pediatric nutritional formula along with dietary education might be an effective approach to promote catch-up growth in children with nonorganic faltering growth.

• Korean Journal of Pharmacognosy
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• v.33 no.3 s.130
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• pp.177-181
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• 2002

This study was carried out to investigate the antioxidative activities of Rosa davurica Pall for the purpose of development of novel antioxidant from natural products. Antioxidant activities of four different parts of Rosa davurica Pall such as fruit, leaf, stem and root were examined by measuring the radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The methanol extract from the root of Rosa davurica Pall showed the highest antioxidative activity among 16 samples tested. And, we also tested radical scavenging effects of 5 different extract compartments(Hexane, $CHCl_3$, EtOAc, BuOH and $H_2O$ fraction). EtOAc and BuOH fractions from the root of Rosa davurica Pall exhibited antioxidative activities higher to those of natural, ${\alpha}-tocopherol$ or synthetic antioxidants, BHT. The antioxidative substance of EtOAc fraction from the root of Rosa davurica Pall was successively purified with silica gel adsorption column chromatography and Sephadex LH-20 column chromatography. The purified active substance was isolated as crystal and identified as (+)-catechin by $^{l}H-NMR$ and $^{13}C-NMR$. This compound exhibited DPPH radical scavenging activity with the $IC_50$ value of $1.7\;{\mu}g/ml$. In the analysis of catechin content, the leaf extracts contained the highest catechin, and fruit extracts contained the lowest catechin. Considering antioxidative activity on DPPH assay, the extracts of Rosa davurica Pall showed a possibility to be used as a new material for natural antioxidant and functional food.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.2
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• pp.145-149
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• 2006

This study investigated the quality characteristics of meat from goat fed fermented grape feeds including chemical composition, physical and sensory properties. The hardness of the goat meat was decreased by feeding fermented grape diets, but no significant difference in the pH was observed between control group and fermented grape diet-fed group. Major minerals in goat meat were shown to be Ca, Na, K and Mg and total amino acid content was the highest in a group fed $20\%$ fermented grape-containing diet (T2) among experimental groups. Major fatty acids in goat meat were linoleic acid, oleic acid, palmitic acid, and stearic acid while the content of oleic acid in meat was significantly increased in the group fed fermented grape diet. By increasing the amount of fermented grape in goat diet, L (lightness), a (redness) and b (yellowness) color parameters of goat meat were increased. From the sensory test, the meat from goat fed $30\%$ fermented grape-containing diet (T3) was evaluated the best, with higher overall acceptability of meat at higher content of fermented grape in goat feeds.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.6
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• pp.594-599
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• 2012

The objective of this study was to determine the processing conditions for salt dried rockfish Sebastes schlegeli by sun drying and cold-air drying, as measured by alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) activity. We processed salt dried rockfish samples. The salinity of rockfish samples was within 1% following salting with 25% salt brine for 3 h. The moisture content of salt dried rockfish was found to reduce linearly from 70.12 to 39.5 g/100 g over the same time interval. The water activities of salt dried rockfish by sun and cold-air drying were 0.94 and 0.87, respectively, after three days of drying. Acid values (AV) were 10.71 and 5.96 mg KOH/g, respectively, after the three day drying period. The ADH activity in a water extract from salt dried rockfish following sun and cold-air drying for 24 h was 228.5% and 226.1% at 13.3 mg/mL, respectively, and was higher than that when drying lasted for 48 and 72 h. The ALDH activity was not affected but both ADH and ALDH activity tended to decrease as the drying time increased from 24 to 72 h. The conditions of processing for the best quality of salt dried rockfish were determined to be drying with a cold-air system for 24 h. These results indicated that water extracts from salt dried rockfish have valuable biological attributes owing to the metabolizing of alcohol and can provide useful information for the design of drying systems for salt dried rockfish.