• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2557-2560
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• 2010

To assay for antioxidant capacity of natural products considered important in producing human health benefits, a practical and economical method using pellet techniques was developed. A standard visualizing reagent, 1,1diphenyl-2-picryl-hydrazyl (DPPH), was mixed with a water-miscible polyvinyl alcohol (PVA), serving as a solid phase support for the DPPH reagent. A DPPH pellet was prepared by dropping a small volume of the DPPH solution onto PET film, and drying in an oven. The PVA-based DPPH pellet was dissolved into water, in which the water-miscible PVA plays as a non-ionic surfactant to help the DPPH reagent to be dissolved into the solvent. Using the DPPH assay, the antioxidant capacity of water-soluble extracts of black soybean, barley, green tea, and green gram was examined. Among the natural products tested, green tea showed the highest antioxidant capacity. This PVA-based DPPH antioxidant assay can be further applied in the natural food, raw plant material, and health product inspection field.

• Journal of Plant Biology
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• v.19 no.4
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• pp.107-110
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• 1976

This study was carried out to investigate lead contamination in the leaves of roadside trees and the cause of yellow-brown symptom of leaves in Jinju and Daegu city. After the leaves were collected and dried in 105$^{\circ}C$ drying oven from September to October in 1974, the samples were used for analysis of the lead contents in 1976. The roadside trees in the two cities were mostly the four kinds of Ginkgo biloba L., Thuja orientalis L., Platanus orientalis L. var. acerifolia AIT. and Prunus pseudo-cerasus $LINDL{\times}Prunus$ subhirtella MIQ. The lead contents in the leaves of roadside trees in Daegu city was higher than that of Jinju city. The lead contamination of the evergreen trees of roadside was higher than that of the deciduous trees. In Jinju city the site of the highest contents of lead in the leaves was revealed with Jinju station(0.73ppm), the next site was revealed with the road(0.16ppm) between Namgang bridge and Jinju middle school, and the lowest site was generally beside the roads of suburbs (0.07ppm). Because of the low contents of lead in the leaves, it was found that the yellow-brown symptoms of leaves were not caused by the lead toxicity.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.91-95
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• 1992

Two experiments were conducted to evaluate the performance of broilers and layers fed locally produced fish waste meal (LFWM) in Western Samoa. LFWM, which was produced by mincing and oven drying of rejects from filleted fish, was included in both broiler and layer diets at the complete expense of imported meat and bone meal (MBM). The experiments were of a completely randomised design. In experiment 1, 120 day-old Strabro broiler chicks were raised to 49 days of ages. In experiment 2, 80 Shaver 288 pullets, 20 weeks of age, were housed in pairs in cages and raised up to 72 weeks of age. There were no differences (p > 0.05) in performance of broilers as measured in terms of final bodyweights, feed intake, feed efficiency and carcass yield between the two diets. Similarly, no differences (p > 0.05) existed in egg production, egg weight and feed required per kilogramme of eggs. It is concluded that LFWM is nutritionally as good as imported MBM and could be used to completely replace MBM in broiler and layer diets.

• Bulletin of the Korean Chemical Society
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• v.6 no.6
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• pp.329-333
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• 1985

A procedure for the preparation of peptizable pseudoboehmite has been described in detail based upon a process of neutralization of an aqueous aluminum sulfate or chloride solution with aqueous ammonia. In order to obtain peptizable pseudoboehmite products, carefully controlled conditions were required in the whole processes of neutralization, aging, washing, and drying. The optimum conditions experimentally found are the following. The aluminum salt solution is neutralized with aqueous ammonia until the final pH of the solution reaches 10.0 to 10.8 or 9.0 to 9.3 for the sulfate of chloride, respectively. The alumina gel formed is subjected to aging at $80^{\circ}C for about 3 hours and washed with water more than 5 times to reduce the residual sulfate or chloride ion in the final products to less than 4%. The pseudoboehmite gel thus obtained should be dried oven at 80 to $100^{\circ}C for a few to several hours depending on the selected temperatures.

• Korean Journal of Food Science and Technology
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• v.44 no.5
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• pp.532-539
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• 2012

Electron spin resonance (ESR) spectroscopy of gamma-irradiated fresh broccoli and kimchi cabbage was conducted to identify their irradiation history. Different pretreatments, such as freeze-drying (FD), oven-drying (OD), alcoholic-drying (ALD), and water-washing and alcoholic-drying (WAD) were used to lower the moisture contents of the samples prior to ESR analysis. The non-irradiated samples exhibited a single central signal ($g_0$=2.0007) with clear effect of $Mn^{2+}$, especially in kimchi cabbage. Upon irradiation, there was an increase in the intensity of the central signal, and two side peaks, mutually spaced at 6 mT, were also observed. These side peaks with $g_1$ (left)=2.023 and $g_2$ (right)=1.985 were attributed to radiation-induced cellulose radicals. Leaf and stem in broccoli, and root and stem in kimchi cabbage provided good ESR signal responses upon irradiation. The signal noise was reduced in case of ALD and WAD pretreatments, particularly due to $Mn^{2+}$ signals. The ALD treatment was found most feasible to detect the improved ESR spectra in the irradiated samples.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.164-168
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• 2005

An experimental design has been used to optimize the analysis of volatile component from fresh ginseng using solvent free solid injector (SFSI). The analysis were performed at three different sample preparing methods (fresh, oven drying and freezed drying), different injector port temperatures (100, 150, 200, 250 and $300^{\circ}C$) and different preheating time (3, 5, 7, 10 and 15 min) according to the above experimental design. The optimum conditions from analytical results were fresh sample (sample preparing methods), $250^{\circ}C$ (injector temperature) and 10 min (preheating time). Ginsengs grown for six years at Gumsan were prepared for fresh, white and red ginsengs. These fresh, white and red singsengs were analyzed for their volatile components by GC/MS equipped with SFSI according to the above the optimum conditions. A total of thirty-three volatile components were identified in fresh ginseng by SFSI, thirty-six in white ginseng and thirty-eight in red ginseng. These results suggested that the SFSI method could be used for isolating volatile component in ginsengs.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.1
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• pp.101-110
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• 2022

In this study, water content tests were performed on various fresh concretes subjected to different binder compostions to review the estimation errors and reliability of water content test methods. Micro-oven drying method, air-meter method, capacitance method and microwave penetration method were used to estimate water content of fresh concrete. Errors in water content estimation were analyzed by each test method. Regardless of the test method of water content, the estimation error was less than 5 %, and in the case of the test using mortar, the error in the estimation value was relatively large. In addition, based on the test results of water content of various concrete, the probability density function in which the estimation error for each test method becomes the population was analyzed. Water content test methods of fresh concrete which using concrete samples showed high estimate reliability of 97 % within the estimation error range of ± 10 kg/m³. On the other hand, the reliability of water content test method using mortar samples was lower.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.300-305
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• 2007

The purpose of this study is to examine changes in the residues of procymidone and diazinon in Chwinamul, pepper leaves, and young radish according to drying method. When the three vegetables were dried at room with air stream, the residues of procymidone and diazinon increased, but after being adjusted to reflect the decrease in water content of the vegetables, the residues declined by 10 to 83 percent. When they were dried in a oven, the residues of the pesticides in the vegetables also increased, but after being adjusted to reflect the drop in the water content, the residues decreased by 44 to 71 percent. According to the results, the residues of the pesticides mostly decreased after being adjusted to reflect the drop in the water content of the dried vegetables. Therefore, when judging dried agricultural products not only the decreased water content of dried vegetables but also other factors that affect pesticide residues during the drying process should be considered. This raises the need for additional research on such factors.

• Food Science and Preservation
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• v.24 no.3
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• pp.464-471
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• 2017

The purpose of this study was to evaluate the effect of superheated steam drying on physicochemical and microbial characteristics of Korean traditional actinidia (Actinidia arguta) leaves. Actinidia leaves were dried at steam temperature of $350^{\circ}C$ and oven temperature of $150^{\circ}C$ for 40-200 sec. Moisture content and water activity decreased with increasing the drying time, while color values including L, a, and b values and total color difference (${\Delta}E$) increased as drying time increased. The relationship between moisture content and water activity showed an exponential fit with high correlation vlaue ($R^2=0.9909$). Total phenolics and flavonoids content and antioxidant activity such as DPPH radical scavenging activity, ABTS radical scavenging activity, and FRAP assay of dried actinidia leaves increased with increasing the drying time up to 160 sec, but dramatically decreased at drying of 200 sec. The numbers of total areobic bacteria of leaves was not detected at drying time over 120 sec and coliform of all the samples was not detected. As a results, the superheated steam was an very effective drying method of increase to the nutritional and sanitary quality of dried Korean traditional actinidia leaves.

• Journal of Ocean Engineering and Technology
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• v.24 no.5
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• pp.67-74
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• 2010

Chromate conversion coating is a coating technique used to passivate aluminum, zinc, cadmium, copper, silver, magnesium, tin, and their alloys to slow corrosion. The process uses various toxic chromium compounds, which may include hexavalent chromium. The industry is developing less toxic alternatives in order to comply with substance restriction legislation, such as RoHS. One alternative is to develop a Cr-free coating solution. In this study, eco-friendly, Cr-free solutions (urethane solution S-700, organic/inorganic solution with Si LRO-317) were used. Test specimens were dried in a drying oven at $190^{\circ}C$ for 3, 5, 7, and 9 minutes. Corrosion resistance was evaluated using a salt spray test for 72 hours. The results show that the optimum corrosion resistance was achieved at $190^{\circ}C$ for five minutes for EGI and three or five minutes for HDGI, respectively. The adhesive properties of the two types of coating solutions were superior regardless of drying time.