• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.352-357
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• 1998

This experiment was conducted to find out the effects of major nutrient levels(N, P, K) on ozone susceptibility of tomato plants(Lycopersicon esculentum Mill, cv. Pink Glory). Plants were grown in water culture system. A half-strength of Hoagland's nutrient solution was considered as a standard formulation($N_{100}$ $P_{100}$ $K_{100}$). The levels of major nutrients were adjusted through addition or removal of several fertilizer salts from the standard solution. Top growth was significantly decreased at the low nitrogen level or phosphorus removal condition. P- and K-contents of leaves were greatly decreased by removal of salts containing P and K from the nutrient solution. The rate of ozone injury was significantly increased when potassium was removed. However, the influence of nitrogen and phosphorus levels or high potassium level on injury occurrence did not show statistical significance compared to the standard solution. Ozone exposure resulted in reduction of chlorophyll, and increase of ethylene production, electrolyte leakage and malondialdehyde(MDA) contents. These changes were much more enhanced in plants grown at the potassium removal solution. Whereas the activity of superoxide dismutase(SOD) was low at the potassium removal treatment and this tendency remained after ozone exposure. These results indicated that potassium nutrient level in tomato plants is closely associated with the susceptibility to ozone injury.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.3
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• pp.1-12
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• 2018

This study was conducted to obtain a reliable result assessing proper amount of solid swine manure for the growth of Deutzia crenata seedlings. Seedling growth dry weight, chlorophyll content inorganic nutrients and soil chemical properties were investigated. 1. When treated with solid swine manure, seed germination rate was highest on the control. However, germination rates tended to decrease when treated with swine manure at high concentrations. 2. The growth of seedlings treated with swine manure was always higher than that of in control. At the 1.0% of swine manure treatment, the growth rate of the seedlings was highest. 3. Seedling dry weight was highest at the 1.0% swine manure treatment. The amount of inorganic nutrients absorbed by the seedling was generally high with the 1.0% treatment, declined sharply with the 2.0% treatment. 4. For the planting soil of Deutzia crenata, the higher the concentration of swine manure, the lower the soil pH. However, nitrogen, available P, K, Na, Mg and Ca contents in the soil have increased with higher concentrations.

• Journal of the Korean Geotechnical Society
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• v.34 no.6
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• pp.49-59
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• 2018

When a tracked vehicle travels off-road, shearing action and ground sinkage occur on the soil-track interface and severely affect tractive performance of the tracked vehicle. Especially, the ground sinkage, which is induced by vehicle's weight (hereinafter referred to as static sinkage) and longitudinal forces in the direction of travel producing slip (hereinafter referred to as slip sinkage), develops soil resistance, directly restricting the tractive performance of an off-road tracked vehicle. Thus, to assess the tractive performance of an off-road tracked vehicle, it is imperative to take both of static sinkage and slip sinkage into consideration. In this research, a series of model track experiments was conducted to investigate the slip sinkage which has not been clarified. Experiment results showed that the slip sinkage increased with increasing the slip ratio, but the increasing rate gradually decreased. Also, the slip sinkage was found to increase as relative density of soil decreased and imposed vertical load increased. From the experiment results, the normalized slip sinkage defined as slip sinkage to static sinkage calculated in the identical condition was investigated, and an empirical equation for the slip sinkage was developed in terms of slip ratio, which allows vehicle operators to predict the slip sinkage in a given soil and operating conditions.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.6
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• pp.15-25
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• 2018

This study was conducted to obtain proper amount of solid poultry manure in the beginning phase of Deutzia crenata growth. Seedling growth increment, dry weight, inorganic matter uptake and chemical changes of soil according to the concentration of solid poultry manure fertilization. 1. When treated with solid poultry manure, seed germination rate was highest on the control. However, germination rates tended to decrease when treated with at high concentrations. 2. The growth of seedlings treated with poultry manure was always higher than that in control. At the 1.0% of poultry manure treatment, the growth rate and dry weight of the seedlings was highest. 3. The amount of inorganic nutrients absorbed by the seedling was generally high with the 1.0% treatment, declined sharply with the 2.0% treatment. 4. For the planting soil of Deutzia crenata, the higher the concentration of poultry manure, the lower the soil pH. However, nitrogen, available P, K, Na and Mg contents in the soil have increased with higher concentrations.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.72-79
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• 2014

This study was investigated the changes in quality of peeled chestnut according to peeling method, including abrasion and knife, and 3 kinds of storage temperatures. The weight loss rate of peeled chestnut during storage period was observed in all treatment groups, peeling methods showed no difference of the loss. However, the moisture content of peeled chestnut during storage in all treatments showed a tendency to decrease. Moisture content of the abrasion peeled chestnut in all treatments was higher than that of the knife peeled chestnut. In the case of a, b, and ${\Delta}E$ value of peeled chestnut chromaticity increased during storage in all treatments, whereas, L values decreased during storage. But, browning of abrasion peeled chestnut was higher than that of the knife peeled chestnut. The hardness of the abrasion and knife peeled chestnuts were the highest in $-1^{\circ}C$ storage, soluble solid content was decreased with storage time in all treatments, but showed a tendency to increase within 24 days. Palatability and texture of peeled chestnuts decreased in all treatments during storage period, 15 days after storage decreased rapidly. Thus, results showed that peeled chestnuts stored at $4^{\circ}C$ and $2^{\circ}C$ were rapidly decreased in the quality after 15 days, whereas, peeled chestnuts stored at $-1^{\circ}C$ slowly decrease in the fruit quality. It can be recommended that chestnut in vacuum film is good to maintain at $-1^{\circ}C$ storage for 15 days. Also, if we can reduce the browning of abrasion peeled chestnut, we will produce peeled chestnut of high quality.

• Journal of Life Science
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• v.19 no.8
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• pp.1088-1092
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• 2009

This study was conducted to determine an estimated value and change in TDF (total dietary fiber) binding major minerals (Ca, P, K Mg) of soybean sprouts depending on cultivation periods of 1, 3 or 5 days, and parts of cotyledon and hypocotyl. The compositions of TDF binding major minerals in soybean sprouts were evaluated by the enzymatic-gravimetric method developed by Prosky and adopted by AOAC. The content of TDF binding P ranged between 915.28 mg and 1037.82 mg per 100 g cotyledon. Average contents of Ca, K, and Mg in cotyledon ranged between 541.67 mg and 634.34 mg, 180.91 mg and 253.98 mg, 231.90 mg and 301.01 mg, respectively, on dry matter basis. The average contents of TDF binding Ca in hypocotyl per 100 g were between 454.36 mg and 540.33 mg, and other major minerals contents were between 149.24 mg and 186.21 mg for P, 164.17 mg and 182.78 mg for K, and 152.53 mg and 161.22 mg for Mg, respectively. The proportional changes of Ca, an estimated value in cotyledon, ranged between 5.58% and 30.98%, 47.18% and 59.10% for P, 95.24% and 95.50% for K, and 58.45% and 68.64% for Mg, respectively, based on dry matter. An estimated value of Ca, P, K, and Mg in hypocotyl ranged between 6.71% and 13.52%, 91.03% and 91.76%, 96.91% and 98.92%, and 61.03% and 66.37%, respectively, on dry matter basis.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.904-909
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• 1996

To investigate effects of sugars on the retrogradation of rice flour gels, sucrose and isomaltooligosaccharide (1, 2, and 5%, w/w on the flour basis were added to 50% Dongjinbyeo rice flour gels and stored at different temperature $(20^{\circ}C,\;4^{\circ}C)$ far 1, 3 and 6 days. Changes on the degree of retrogradation (DR) of these rice flour gels were measured by α-amylase-iodine method, DSC and X-ray diffractometry. DRs of rice flour gels increased over storage and showed a rapid increase up to 3 days and then decreased thereafter. DRs of rice flour gels with sucrose or oligosaccharide also increased rapidly until 3 day storage but these values were lower than those of rice flour gels without sugar. DRs of rice flour gels with oligosaccharide were lower than those of gels with sucrose. Changes in enthalpy of rice flour gels measured by DSC showed the same tendency with those in DRs of rice flour gels by ${\alpha}-amylase-iodine$ method, but varied with sugar levels.

• Food Science and Preservation
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• v.13 no.2
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• pp.144-153
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• 2006

The effects on deacidification of citrus fruits produced at early harvesting season for juice products were examined by heating treatment of raw fruits and electrodialysis of juice. Weight and total acidities were decreased by heating treatment for 40 hr at $25^{\circ}C,\;30^{\circ}C,\;35^{\circ}C\;and\;40^{\circ}C$, but $^{\circ}Brix$ and pH increased Sugar to acid ratio also increased. Total acidities were decreased from 1.25 (Oct30, 2004), 1.24 (Nov.5, 2004), 0.99 (Nov.13, 2004) and 0.98% (Nov.19, 2004) to 0.48 (Oct30, 2004), 0.51 (Nov.05, 2004), 0.37 (Nov.13, 2004) and 0.42% (Nov.19, 2004) by electrodialysis for 100 min respectively, and $^{\circ}Brix$ also slightly decreased, but solid to acid ratio was increased as a result. However pH and color remained almost unchanged by electodialysis. Also, free sugar contents of citrus juice little were changed, but organic acid content were decreased fairly. Narirutin and hesperidin content among flavonoids were slightly decreased by electrodialysis, but they were not significantly different. $K^+,\;PO_4^{2-},\;SO_4^{2-}\;and\;Cl^-$ content were decreased by electrodialysis, and $K^+$ contents decreased by more than 80% However, $Na^+$ consent was increased by about 2 times. Total polyphenol contents and electron donating abilities were decreased a little by electrodialysis but nitrite scavenging abilities were little changed. By acceptability test citrus juice prepared by electrodialysis for 100 min was superior to original citrus juice.

• Journal of Mushroom
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• v.2 no.4
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• pp.200-206
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• 2004

The optimal temperature for mycelial growth the F. fomentarius was $30^{\circ}C$ and the range of the temperature for mycelial growth wsa about 10~30. The optimal pH for the growth was 4.0. The percentage of weight loss percentage wsa 17.4%. The percentage of WEC extractives wsa increased to 2.24%. The observation of micromorphological showed that the detected cell wall were erosive and thinning as typical degradation pattern of white-rot fungi.

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.533-537
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• 2015

Micro-algae Chlorella vulgaris (C. vulgaris) is an important source for bio-diesel because of the high content of neutral lipids. In this study, we intended to induce mutants of C. vulgaris by UV-B irradiation. C. vulgaris was first exposed to UV-B for 1, 2, 3, 4, 5 min. As the UV-B exposure time increased, the cell viability and pigment content were decreased. Mutants of C. vulgaris were also induced through ultraviolet irradiation and two strains were selected with respect to lipid contents, where were named as 'UM10', 'UM15'. They were then cultivated in the same way as to the wild type. After 21 days of cultivation, the cell growth, dry cell weight, pigment contents, and lipid contents were measured for investigating characteristics of mutants. As a result, the cell growth and dry cell weight of both mutants increased about 1.4 and 1.5 times, respectively compared with those of wild type. In addition, chlorophyll and carotenoid contents were measured in order to investigate pigment contents in micro-algae through photosynthesis. It was shown that chlorophyll and carotenoid contents of both mutants decreased about 10% compared to those of wild type. Lipid contents in UM10 and UM15 increased about 1.2 and 1.5 times, respectively compared to that of wild type.