• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.5
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• pp.475-481
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• 2000

The growth of the microalgal Spiulina platensis in a batch photobioreactor had been studied to determine the influence of temperature, light intensity, and culture medium on the growth and c-phycocyanin content of the biomass. The most favorable conditions for high biomass and c-phycocyanin production were as follows: light intensity of 3500 lux, temperature of $35^{\circ}C,\;NaHCO_3\;of\;1.0{\%}$ for pH control, $0.2{\~}0.3{\%}\;Na_2CO_3$ for carbon source, and $0.2{\~}0.3{\%}\;NaCO_3$ for nitrogen source. The c-phycocyanin and chlorophyll content on most favorable condition were about $11{\%},\;1.0{\%}$, respectively.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.2
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• pp.55-66
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• 1988

This study was conducted to investigate the various engineering properties and correlationshops among the soil constants of alluvial clayey deposits distributed in the bay of Asan and their results are summarized as follows : 1. Grain size distribution of soil was consisted of 12 % of clay, 46-73 % of silt, 2-23 % of sand, and as for the consistency characteristics, 26-36 % of liquid limit, 18-21 % of plastic limit and 6-16 % of plastic index, and so the soil belonging to as a lower plastic nonorganic clay, it's specific gravity was 2,66-2.70, and the location on the plastic chart was approximately above the A-line. Z The natural moisture content and unit weight were 30-43 % and 1.76-1.87 g I cm$_3$, respectively, and according to increment of natural moisture content, the unit weight was decreased, and the initial void ratio and degree of saturation were shown of 0,87-1119 and 92- 100 %, most of saturated. 3. Cone resistance value which was shown 2.4 - 6.5 kg / $cm^2$ was a little lower and it was increased with the depth of layer and shown the formular $q_c=0.7_z+1.32$. 4. Unconfined compression strength was about 0.18-0.43kg /$cm^2$, cu, 0.1-0.22kg / $\psi$, $2-6^{\circ}$ under uu-test condition of triaxial, and CCU, 0.08-0.3 kg/cm , $\psi$, $12-18^{\circ}$ under the condition of cu-test. 5. Pre-consolidation load of characteristics of consolidation was 0.4-0.8 kg / $cm^2$, compression index, about 0.17-0.33. 6. Liquid limit and plastic index were incresased with the increment of clay content but most of alluvial clay was appeared as a normal through non-activity clay soil shown more natural moisture content than liquid limit, and their relationship as follows : LL=0.38( cy+54.8), PI=0.836(LL -17.8), PI =0.468(LL -0.48) 7. The initial void ratio presented correlationship of positive among clay content, natural moisture content and liquid limit, and that of reverse with unit weight, and their results as follws : $e_o=0.024(w_n+0.2)$, $e_o=e_o=0.0003c_y+0.0005 LL+0.0151 W_n+\frac{3.58}{r-t}-1.52$ 8. It was shown that the compression index has correlationship of postive among the clay content, liquid limit, plastic index, natural moisture content and initial void ratio, and their relationships as follows ; $c_c=0.44(e_o-0.47)$, $c_c=0.001$

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.310-316
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• 2001

Poly-3-hydroxybutyrate (PHB) synthase catalyzed the last enzymic step to synthesize the intracellular PHB of Rhodobacter sphaeroides. No PHB was detected when the phbC coding for PhB synthase was interrupted, and its expression was regulated at the level of transcription. The cellular PHB content increased about four- to six-fold during the growth transition from the exponential to the early stationary phase under both aerobic and photoheterotrophic conditions. The PHB content during the aerobic growth seemed to be determined by the PhB synthase activity. However, the PHB synthase activity of photoheterotrophically grown cells did not correlate with the PhB content, suggesting a photoheterotrophic regulation different from the aerobic control. Thus, the PHB content of R. sphaeroides was regulated at the transcription level only under aerobic conditions.

• Horticultural Science & Technology
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• v.29 no.4
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• pp.311-316
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• 2011

This study aimed to determine the effect of EC (electrical conductivity) levels of nutrient solution in hydroponic culture on allyl-isothiocyanate (AITC) content within plant tissues, Vitamin C content and physiological responses in wasabi plant (Wasabia japonica M. 'Darma'). The 'Darma' was grown for 5 weeks with a deep flow technique (DFT) system controlled at 5 different EC levels, including 0.5, 1, 2, 3, and $5dS{\cdot}m^{-1}$. In result, the highest total content of AITC showed at EC level 5 and $3dS{\cdot}m^{-1}$ for 1 or 5- week, respectively. The total content of AITC increased about 1.2-1.4 times when the plants were grown in the EC levels between 0.5 and $2dS{\cdot}m^{-1}$, whereas the content decreased about 6 and 56 % in the EC level 3 and $5dS{\cdot}m^{-1}$, respectively. The content of AITC was relatively higher in petiole tissue, about 53 %, taken from 1 week-grown plants when the EC was controlled between 0.5 and $2dS{\cdot}m^{-1}$. Root tissue also had relatively higher content of AITC, about 45.1 %, when the EC was controlled at 3 and $5dS{\cdot}m^{-1}$. However, a 5-fold decrease in the AITC content was found in blade tissue and a 6.8-fold decrease in root when the EC was controlled at $5dS{\cdot}m^{-1}$ for 5 weeks. There was no significant difference in the vitamin C content in 1-week grown leaf tissues under the different EC level treatments; but, the content increased about 27% in 5-week grown plants at the EC level between 0.5 and $2dS{\cdot}m^{-1}$, compared to the 1 week-grown leaf tissue. Electrolyte leakage of leaf tissue taken from 3-week grown plant was 3-fold higher at the EC level $5dS{\cdot}m^{-1}$, compared to the EC level between 0.5 and $2dS{\cdot}m^{-1}$. Chlorophyll content, photosynthesis rate and transpiration rate were decreased when the EC was controlled at higher than $2dS{\cdot}m^{-1}$. Leaf water content, specific leaf area and growth were decreased when the EC was controlled at $5dS{\cdot}m^{-1}$ for 5 weeks. All the integrated results in this study suggest that the EC level of nutrient solution should be maintained at lower than $3dS{\cdot}m^{-1}$ in order to improve nutritional value and quantity required for hydroponically grown wasabi as functional vegetable.

• Journal of the Korean Ceramic Society
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• v.27 no.8
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• pp.1055-1063
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• 1990

The early hydration characteristics of the system $C_3S-C_3A-C_4AF$ according to the clinker composition variations, in order to establish the mutual interactionof clinker minerals during the portland cement hydration, have been studied. The early hydration rate of $C_3S$ was greatly effected by the change of $C_3S/C_3A$ ratio. The lower the $C_3S/C_3A$ ratio was, the faster the apex reaching time and the rate of heat liberation of the 2nd exothermic peak originating from the formation of $Ca(OH)_2$ were. The effect of $C_3S/C_3A$ ration on the amounts of $Ca(OH)_2$ formation was decreased, in process of hydration time, but the effect of $C_3S$ content was increased.

• Culinary science and hospitality research
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• v.23 no.4
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• pp.185-192
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• 2017

This study examined the optimum conditions and obtained the basic data for processing semi-dried sea cucumber flakes. During the boiling process, the weight and length of the sea cucumber decreased to 45.61% and 55.87%, respectively. Thereafter, there was a gradual decrease in the weight and length of the sea cucumber, which were finally maintained at 30.00% and 50.93%, respectively. The moisture content during drying was 38.37% after 3 hours at $60^{\circ}C$, and 36.56% after 5 hours at $30^{\circ}C$. However, the decrease in moisture content was slowly at 60 hours and $4^{\circ}C$, reaching a final value of 68.9%. The length of boiled sea cucumber during drying decreased to 66.35% after 11 hours at $60^{\circ}C$, and 68.90% after 24 hours at $30^{\circ}C$. The chromaticity and hardness tended to increase during the drying process. Moisture content and water activity of sea cucumber flakes decreased from 81.48% (0.963) to 33.50% (0.763), respectively, after 3 hours at $60^{\circ}C$. Following this, the moisture content and water activity continuously decreased to 30.75% (0.608) at 4 hours and 19.47% (0.437) at 5 hours, respectively. The overall acceptance score was 4.11 and 3.89 for 4 hours dry sample and 5 hours dry sample, respectively. However, the score was not statistically significant.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.415-423
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• 2018

The aim of this study was to evaluate the individual glucosinolate (GSL), total phenol, total flavonoid, and vitamin C content, and antioxidant activity under various light quality condition, mainly focusing on red (R) to far-red (FR) light ratios in three Brassica sprouts (radish, Chinese cabbage, and broccoli). Three R/FR ratio of 0.6, 1.3, and 2.0 were exposed to 5-day old sprouts for 48 h in a controlled environment, and the targeted phytochemical contents and antioxidant activities were compared with three separate control plot of dark, fluorescent, and red:blue 8:2 conditions. Total GSL content was highest in broccoli among the cultivars throughout the respective treatments, and increased with the increasing of R/FR ratio in the broccoli sprouts, while the content showed non-significant results in the Chinese cabbage sprouts. The progoitrin, a major GSL in Chinese Cabbage and broccoli, content decreased by upto 38% and 69%, respectively, with decreasing the R/FR ratio compared to the control plots (fluorescent, red:blue 8:2, and dark condition). The contents of phenol, flavonoid, and vitamin C were lowest in dark condition in all the three Brassica sprouts. The total phenol content and antioxidant activities increased with decreasing the R/FR ratio in all the Brassica sprouts, while total flavonoid and vitamin C content showed different patterns depending upon the Brassica sprouts. These results suggest that additional use of FR is expected to improve the functional quality of Brassica sprouts in different ways.

• Nuclear Engineering and Technology
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• v.49 no.4
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• pp.873-880
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• 2017

To identify the feasibility of disposing of spent activated carbon as a clearance level waste, we performed characterization of radioactive pollution for spent activated carbon through radioisotope analysis; results showed that the C-14 concentrations of about half of the spent activated carbon samples taken from Korean NPPs exceeded the clearance level limit. In this situation, we selected thermal treatment technology to remove C-14 and analyzed the moisture content and thermal characteristics. The results of the moisture content analysis showed that the moisture content of the spent activated carbon is in the range of 1.2-23.9 wt% depending on the operation and storage conditions. The results of TGA indicated that most of the spent activated carbon lost weight in 3 temperature ranges. Through py-GC/MS analysis based on the result of TGA, we found that activated carbon loses weight rapidly with moisture desorption reaching to $100^{\circ}C$ and desorbs various organic and inorganic carbon compounds reaching to $200^{\circ}C$. The result of pyrolysis analysis showed that the experiment of C-14 desorption using thermal treatment technology requires at least 3 steps of heat treatment, including a heat treatment at high temperature over $850^{\circ}C$, in order to reduce the C-14 concentration below the clearance level.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.159-163
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• 2013

As mulberry fruit's functionalities are known to the media, the interest in promoting of consumption and processed products is increasing. But there is no C3G(Cyanidin-3-glucoside) data based on the stability of the pigment during processing. To solve this problems, and to expand the use of mulberry fruit, processing methods was developed for mulberry fruit juice improved cyanidin-3-glucoside(C3G) stability. The results obtained are summarized as follows. The food additive citric acid with 0.3 % improved C3G content and antioxidant ability in the treatment of mulberry fruit and sucrose the ratio of 50 % : 50 %(w/w). In the case of the addition of oligosaccharides, citric acid decreased antioxidant ability. Xylitol treatment showed up the lowest of C3 content, but by the addition of citric acid improved the pigment content and antioxidant activity of the mulberry fruit juice. Addition of citric acid was more affected C3G stability than containers (clear glass bottles, brown glass bottles, aluminum foil, green glass bottle, translucent glass bottles). In the processing of mulberry juice, 3 minutes blanching treatment using microwave dropped C3G content somewhat. Therefore, using this method is not recommended. However in the antioxidant ability, microwave blanching showed a stabilizing effect compared to the other treatments.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1615-1622
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• 2014

An accurate assessment of moisture content in feed ingredients is important because moisture influences the nutritional evaluation of feedstuffs. The objective of this study was to evaluate various methods for moisture content determination. In Exp. 1, the weight loss on drying (LOD) of corn, soybean meal (SBM), distillers dried grains with solubles (DDGS), whey permeate, whey powder, spray-dried porcine plasma (SDPP), fish meal, and a mixed diet of these 7 ingredients were measured by oven drying at $135^{\circ}C$ for 2 h. Additionally, the samples were dried at $105^{\circ}C$ for 3, 6, 9, 12, or 15 h. The LOD contents of the DDGS, whey permeate, and whey powder measured by drying at $135^{\circ}C$ for 2 h were greater than the values measured by drying at $105^{\circ}C$ for 3 h (p<0.05). All samples except SDPP (p = 0.70) dried at $105^{\circ}C$ for 6, 9, 12, or 15 h caused more LOD compared with the samples dried for at $105^{\circ}C$ for 3 h (p<0.05). The LOD contents of the individual ingredients were additive when dried at $105^{\circ}C$ regardless of drying time. In Exp. 2, moisture contents of corn, SBM, wheat, whey permeate, whey powder, lactose, and 2 sources of DDGS (DDGS1 and DDGS2) were measured by the Karl Fischer method, oven drying at $135^{\circ}C$ for 2 h, and oven drying at $125^{\circ}C$, $115^{\circ}C$, $105^{\circ}C$, or $95^{\circ}C$ for increasing drying time from 1 to 24 h. Drying samples at $135^{\circ}C$ for 2 h resulted in higher moisture content in whey permeate (7.5% vs 3.0%), whey powder (7.7% vs 3.8%), DDGS1 (11.4% vs 7.5%), and DDGS2 (13.1% vs 8.8%) compared with the Karl Fischer method (p<0.05). Whey permeate and whey powder were considerably darkened as the drying time increased. In conclusion, drying samples at $135^{\circ}C$ for 2 h is not appropriate for determining the moisture content in whey permeate, whey powder, or DDGS as well as the mixed diet containing these ingredients. The oven-drying method at $105^{\circ}C$ for 5 to 6 h appears to be appropriate for whey permeate and whey powder, and at $105^{\circ}C$ for 2 to 3 h for DDGS.