• Korean journal of food and cookery science
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• v.19 no.4
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• pp.463-469
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• 2003

This study was carried out to investigate the antioxidant activities of Dansam (S. miltiorrhiza). The Dansam (S. miltiorrhiza) was extracted with ethanol and methanol, and the extracts were fractionated with hexane, chloroform, ethyl acetate and butanol and water, in that order. The antioxidant activities of Dansam (S. miltiorrhiza) were determined by measuring the radical scavenging effects, using the 1, l-diphenyl-2-picryl-hydrazyl (DPPH) method. The electron donating ability was shown to be about 50% (IC50) at concentration of L-ascorbic acid, Dansam that reflected eliminatory effect by 50% were 9.48$\mu\textrm{g}$/$m\ell$, 8.28$\mu\textrm{g}$/$m\ell$, and l2.59$\mu\textrm{g}$/$m\ell$ respectively. According to the results of the above anti oxidation experiments, those for the group with the added Dansam showed a decreased oxidation, but the antioxidation increased with time. With a storage temperature of 60 C for 5 days, the acid value for the relative antioxidant activities were higher than in the Control group. The peroxide values for the relative antioxidant activities were also higher than in the Control group. The TBA values for the relative antioxidant activities were higher than in the Control group.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.45-52
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• 2013

Brewer's spent grain (BSG) is a by-product of beer manufacturing. This study was conducted to evaluate the effect of dietary fiber extracts from brewer's spent grain on quality characteristics of chicken patties. The total fiber content of BSG dietary fiber extracts after extraction increased from 58.11% to 68.57%, and the extracted dietary fiber extracts were added to chicken patties at 0, 1, 2, 3, and 4%, respectively. The effects of the BSG dietary fiber extracts on pH, color, cooking loss, reduction in patty diameter, salt-soluble protein solubility, texture, and sensory characteristics of chicken patties were evaluated. The addition of BSG dietary fiber extracts decreased pH and lightness values, and increased redness and yellowness. Chicken patties formulated with 3-4% BSG dietary fiber extracts had the lowest cooking loss among all treatments (p<0.05). The diameter of chicken patties was not affected by the addition of BSG dietary fiber extracts. Additionally, no significant difference was observed in salt-soluble protein solubility after adding 3% BSG dietary fiber extracts compared to that in the control. Textural and sensory properties were different among the chicken patties, and the 3% BSG dietary fiber-added chicken patty had the highest acceptability. Our results indicate that 3% BSG dietary fiber extract can be used as a good source of dietary fiber for improving the quality characteristics of chicken patties.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3719-3725
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• 2012

Due to the recent shortage of well-graded river sand resulting from a rapid growth of concrete construction, sea sand, crushed sand, and etc. are increasingly used instead. It is, however, well noted that non-washed sea sand leads to corrosion of the reinforcing steel in concrete, and thus eventually results in damage to concrete. Also, the crushed sand is not being widely used, since it is difficult to maintain the allowable amount of passing 0.08mm sieve and to adjust grading. On the other hand, because the fine sand of Nakdong-River has a poor grading but good quality as a fine aggregate for concrete, it is strongly needed to investigate the fine sand as an alternative fine aggregate. Thus, the purpose of this research is to evaluate the physical properties of the fine sand of Nakdong-River to utilize it actively as a fine aggregate. For this purpose, after the sand samples were collected according to typical location of main stream of Nakdong-River, the physical properties such as density in oven-dry condition, grading, unit volume mass, and etc. of them were estimated. It was observed from the test results that physical properties of the fine sand of Nakdong-River except grading were found to be excellent.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.461-466
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• 1991

For the purpose of improving storability and process adaptability of potato, we carried out an experiment to investigate the effects of microwave heating on the total lipid content and fatty acid composition of the potatoes in storage. The samples were made by powdering potatoes exposed to the microwave energy in a 560W, 2,450MHz oven for 0, 60, 120 and 180 seconds respectively. From the examination of the samples stored at th temperature of $25{\pm}1^{\circ}C$ for 12 months, the following results were obtained. As an over-all tendency, the longer the samples were heated and the longer they were stored, the total lipid content decreased but the microwave-heated samples showed decreasing rates less than those of the controls for the whole storage periods. As major fatty acids of the potato flour, linoleic acid (30.92 %), palmitic acid (29.34 %), linolenic acid (8.90 %) and stearic acid (8.23 %) were detected from the samples. The longer the samples were exposed with microwave, unsaturated fatty acids like 18:2, 18:3 increased. generally with the lapse of storage time, saturated fatty acids increased while unsaturated ones decreased. But in the samples heated with microwave, we observed an apparent suppression of the increasing rate of the saturated fatty acids and the decreasing rate of the unsaturated fatty acids, and the suppressing effects turned out to be proportional to the length of microwave heating.

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.692-698
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• 2001

This study has been carried out to estimate aboveground biomass and net primary production(NPP) in an average 41-years-old Quercus variabilis stand of Gongju area, 45-years-old Quercus variabilis stand of Pohang area, and 54-years-old Quercus variabilis stand of Yangyang area. Ten sample trees were cut in each forest and soil samples were collected in July to August, 2000. Estimation for aboveground biomass and net primary production were made by the equation model $Wt=aD^b$ where Wt is oven dry weight in kg and D is DBH in cm. Total aboveground biomass was 91.31ton/ha in Gongju area, 207.6ton/ha in Pohang area, and 71.39ton/ha in Yangyang area. The aboveground biomass 207.6ton/ha in Pohang area is the highest biomass production among the amount of biomass in Quercus variabils stands reported in Korea. The proportion of each tree component to total aboveground biomass was high in order of bolewood, bolebark, branches and leaves in the three forests. Aboveground total net primary production was estimated at 7.8ton/ha in Gongju area, 11.5ton/ha in Pohang area, and 6.40ton/ha in Yangyang area. There were at least 2 times higher total aboveground biomass in Pohang area than in the Gongju and Yangyang areas because of climate difference among the study areas.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.447-451
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• 2019

6-gingerol can be converted to 6-shogaol, one of the predominant active compounds found in ginger, via processing such as drying and extraction. Subcritical water extraction is the environmentally friendly method of extraction of bioactive compounds using only purified water as a solvent. This study investigated subcritical water extraction ($190^{\circ}C$, 15 min) of 6-gingerol, and 6-shogaol from dried ginger (Zingiber officinale) including drying conditions such as temperature (room temperature, 60, $80^{\circ}C$, and freeze drying) and time duration for drying (1-4 h). The amount of 6-gingerol was found to be reduced, and that of 6-shogaol was found to be increased depending upon the water content of dried ginger. Upon oven-drying ginger at $60^{\circ}C$ for 2 h, the maximum yields of 6-gingerol ($0.18{\pm}0.02mg/g$ fresh weight), and 6-shogaol ($0.47{\pm}0.02mg/g$ fresh weight) were obtained upon subcritical water extraction.

• Journal of Adhesion and Interface
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• v.4 no.1
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• pp.28-34
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• 2003

Steel tire cords were subjected to plasma polymerization coating of acetylene in order to enhance the adhesion to rubber compounds. Plasma polymerization coating was varied to plasma polymerization coating of acetylene, argon plasma etching+plasma polymerization, or argon plasma. etching+plasma polymerization with Ar carrier gas. Adhesion was evaluated via TCAT samples and compared to those with brass coated tire cord. For durability study, plasma polymer cooled tire cords were aged in lab atmosphere for 1, 3, 5, 10 or 15 days, while TCAT specimens prepared with plasma polymer coated tire cords were aged in distilled water, 10% NaCl solution or $100^{\circ}C$ oven for 1, 2, 3 or 4 weeks. After testing, failure surfaces were analyzed with SEM/EDX. Among the treatments, the highest adhesion was obtained by Ar etching+acetylene plasma. polymerization coating with Ar carrier gas, providing almost same pull-out force as the brass coated tire cords. Upon the aging of the tire cords in the lab atmosphere, brass coated tire cords provided better adhesion than plasma polymer coated tire cords, while the TCAT samples with plasma polymer coated tire cords exhibited similar or slightly superior durability to those with brass coated tire cords.

• Journal of the Korea Organic Resources Recycling Association
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• v.19 no.3
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• pp.54-62
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• 2011

This study was undertaken to investigate the effects of bone waste on the conservation of nitrogen in aerobic composting process by inducing the struvite crystallization, which was known as a powerful method for conservation of nitrogen in composting reaction. Bone waste was dried at oven and crushed to less than 3 mm prior to use. It was found phosphorus content in bone waste was about 20.9% of the fixed solids from the leaching experiments using sulfuric acid. Addition of seed compost affected the progress of composting reaction substantially. In case seed compost was not used, the duration of initial low pH was greater than seed compost was added. This prolonged acidic pH may have a beneficial effect on the leaching of P from the bone waste and struvite crystallization. The struvite crystallization and resulting conservation of nitrogen by addition of bone waste was confirmed by both reduction in ammonia loss and increased ammonia content in compost. However the level of struvite crystallization observed with bone waste addition may be less than the cases water-soluble phosphate salts were used.

• Resources Recycling
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• v.30 no.5
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• pp.38-48
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• 2021

In this study, we determine the optimal process conditions for selectively recovering Si from a solar cell surface by removal of impurities (Al, Zn, Ag, etc.). To selectively recover Si from solar cells, leaching is performed using HCl solution and an ultrasonic cleaner. After leaching, the solar cells are washed using distilled water and dried in an oven. Decompression filtration is performed on the HCl solution, and ICP-OES (Inductively Coupled Plasma Optical Emission spectroscopy) full scan analysis is performed on the filtered solution. Furthermore, XRD (X-ray powder diffraction), XRF (X-ray fluorescence), and ICP-OES are performed on the dried solar cells after crushing, and the purity and recovery rate of Si are obtained. In this experiment, the concentration of acid solution, reaction temperature, reaction time, and ultrasonic intensity are considered as variables. The results show that the optimal process conditions for the selective recovery of Si from the solar cells are as follows: the concentration of acid solution = 3 M HCl, reaction temperature = 60℃, reaction time = 120 min, and ultrasonic intensity = 150 W. Further, the Si purity and recovery rate are 99.85 and 99.24%, respectively.

• Korean Journal of Environmental Agriculture
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• v.37 no.3
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• pp.213-220
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• 2018

BACKGROUND: This study was carried out to determine characteristics of residual pesticides in time-dependent manner and calculate half-lives of the residual pesticides in fresh and dried Chinese matrimony vine. In addition, processing factors were calculated based on the residual concentrations in them. METHODS AND RESULTS: The test pesticides, etofenprox and fenitrothion, were sprayed onto the Chinese matrimony vine plants at once or twice (at seven-day interval) and then samples were collected at 0 (after 3 hours), 1, 3, 5 and 7 days after the last spraying. Dried samples were prepared in hot-air drying oven at $60^{\circ}C$ for 48 hours until water content of less than 20%. Residual concentrations of etofenprox in fresh and dried samples decreased by 54.0-60.9% after 7 days of the last pesticide-application. In case of fenitrothion, the concentrations were found to have decreased by 69.2-76.5%. Processing factors of etofenprox were 2.6-3.0 for the one-time spraying and 2.5-3.0 for the two-time spraying and those of fenitrothion were found to be 1.5-22 for the one-time spraying and 1.6-2.0 for the two-time spraying. First half-lives of etofenprox and fenitrothion in fresh and dried samples ranged from 5.0 to 6.3 and from 3.4 to 4.0 days, respectively. The third half-lives were found to be 15.0-18.9 and 10.2-12.1 days, respectively. CONCLUSION: Residual concentrations of the tested pesticides in the studied crop decreased, but those in the dried samples appeared to have increased. In addition, processing factor and half life were constant regardless of spraying times.