• Journal of Environmental Impact Assessment
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• v.24 no.3
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• pp.278-286
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• 2015

Pilot scale system was designed to identify the growth and movement of algae, depending on environmental changes(retention time, nutrient concentration, etc) in Gangjeong-Goryeong Weir of the Nakdong River. Considering the stability of algal culture and easy observation of algal growth, pilot scale system was made of transparent acrylic material(3 sets of flexible cylindrical water tanks with 1 m diameter and 4 m height). Auxiliary equipments include light intercepter, water inflow device for different water depth and storage of reclaimed water. The retention time was 2 days(before construction of weir; treatment 1), 8 days(after construction of weir, 2013; treatment 2) and 30 days(2014; treatment 3). According to the water temperature of treatment 1 were similar by depth, treatment 3 showed a difference between the surface(0 m) and bottom(4 m) more than $3^{\circ}C$. DO, pH showed relatively high in the surface than the bottom. Nutrients showed eutrophic condition in all experiments. The Chlrophyll-a concentration of the treatment 1 showed a relatively lower value than the Chlrophyll-a concentration of the treatment 2 and 3. Therefore, the retention time was considered to influence the growth of phytoplankton.

• Korean Journal of Food Science and Technology
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• v.49 no.1
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• pp.8-13
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• 2017

Octenyl succinylated (OSA) potato starch was dextrinized by two methods: ultrasound (at 25, 50, or $70^{\circ}C$ for 1 h; OSA-25UT, OSA-50UT, and OSA-70UT, respectively) and acid hydrolysis (for 1 or 4 h; OSA-AD1H or OSA-AD4H, respectively), and the properties of the resulting starch were analyzed. The melting enthalpy of OSA-70UT decreased the most (from 14.0 to 10.0 mJ/mg), indicating chain degradation. For pasting properties, as ultrasound treatment temperature increased, peak viscosity decreased (2884, 2550, and 1888 cP, respectively), whereas acid hydrolysis increased peak viscosity and decreased pasting temperature. The relative crystallinity of OSA-dextrin produced by ultrasound or acid hydrolysis significantly decreased (from 33.61 to 14.90-26.03 and 19.28-20.05, respectively) as temperature or time increased, yet a B-type crystal pattern was maintained. Regarding emulsifying stability and sensory tests of mayonnaise prepared with OSA potato dextrin, mayonnaise with OSA-70UT was stable for short storage period (1 week), however mayonnaise with OSA-AD1H was the most suitable for long storage periods (from 2 to 4 weeks). In addition, the OSA-70UT was the most acceptable for mayonnaise in the sensory test.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.3
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• pp.189-196
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• 2022

Plasma refers to an ionized gas that is often referred to as "the fourth phase of matter", following solid, liquid, and gas. Plasma has traditionally been utilized for industrial applications such as welding and neon signs, but its promise in biomedical fields such as cancer treatment and dermatology has lately been recognized. Indeed, due to its beneficial effects in promoting collagen production, improving skin tone, and eliminating harmful bacteria in the skin, plasma treatment constitutes an important target for dermatological research. In this study, a plasma device for cosmetic manufacturing based on nitrogen, the main component of the atmosphere, was designed and assembled. Moreover, nitric oxide (NO) was selected since is easier to follow and evaluate than other nitrogen plasma active species, and its contents were measured to perform a quantitative and qualitative evaluation of plasma. First, an injection method, using different proximities labeled "sinking" and "non sinking" treatments, was performed to test the most efficient plasma treatment method. As a result, it was observed that the formulation obtained by a non sinking treatment was more effective. Furthermore, toner and ampoule were selected as cosmetics formulations, and the characteristics of the formulation and changes in the injected plasma state were observed. In both formulations, the successful injection of NO plasma was 2 times higher in toner formulation than ampoule formulation, and it gradually decreased with time, having dissipated after a week. It was confirmed that the nitrogen plasma used did not affect the stability of the toner and ampoule formulations at low temperature (4 ℃), room temperature (25 ℃), and high temperature (37 ℃ and 50 ℃) conditions. The results of this study demonstrate the potential of plasma cosmetics and highlight the importance of securing the stability of the injected plasma.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s02
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• pp.13-33
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• 1989

Agroclimate should be analyzed and evaluated accurately to make better use of available chimatic resources for the establishment of optimum cropping systems. Introducing of appropriate cultivars and their cultivation techniques into classified agroclimatic zone could contribute to the stability and costs of crop production. To classify the agroclimatic zones, such climatic factors as temperature, precipitation, sunshine, humidity and wind were considered as major influencing factors on the crop growth and yield. For the classification of rice agroclimatic zones, precipitation and drought index during transplanting time, the first occurrence of effective growth temperature (above 15$^{\circ}C$) and its duration, the probability of low temperature occurrence, variation in temperature and sunshine hours, and climatic productivity index were used in the analysis. The agroclimatic zones for rice crop were classified into 19 zones as follows; (1) Taebaek Alpine Zone, (2) Taebaek Semi-Alpine Zone, (3) Sobaek Mountainous Zone, (4) Noryeong Sobaek Mountainous Zone, (5) Yeongnam Inland Mountainous Zone, (6) Northern Central Inland Zone, (7) Central Inland Zone, (8) Western Soebaek Inland Zone, (9) Noryeong Eastern and Western Inland Zone, (10) Honam Inland Zone, (ll) Yeongnam Basin Zone, (12) Yeongnam Inland Zone, (13) Western Central Plain Zone, (14) Southern Charyeong Plain Zone, (15) South Western Coastal Zone, (16) Southern Coastal Zone, (17) Northern Eastern Coastal Zone, (18) Central Eastern Coastal Zone, and (19) South Eastern Coastal Zone. The classification of agroclimatic zones for cropping systems was based on the rice agroclimatic zones considering zonal climatic factors for both summer and winter crops and traditional cropping systems. The agroclimatic zones were identified for cropping systems as follows: (I) Alpine Zone, (II) Mountainous Zone, (III) Central Northern Inland Zone, (IV) Central Northern West Coastal Zone, (V) Cental Southern West Coastal Zone, (VI) Gyeongbuk Inland Zone, (VII) Southern Inland Zone, (VIII) Southern Coastal Zone, and (IX) Eastern Coastal Zone. The agroclimatic zonal characteristics of climatic disasters under rice cultivation were identified: as frequent drought zones of (11) Yeongnam Basin Zone, (17) North Eastern Coastal Zone with the frequency of low temperature occurrence below 13$^{\circ}C$ at root setting stage above 9.1％, and (2) Taebaek Semi-Alpine Zone with cold injury during reproductive stages, as the thphoon and intensive precipitation zones of (10) Hanam Inland Zone, (15) Southern West Coastal Zone, (16) Southern Coastal Zone with more than 4 times of damage in a year and with typhoon path and heavy precipitation intensity concerned. Especially the three east coastal zones, (17), (18), and (19), were subjected to wind and flood damages 2 to 3 times a year as well as subjected to drought and cold temperature injury.

• The Journal of Korean Academy of Prosthodontics
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• v.38 no.5
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• pp.595-605
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• 2000

Dental ceramics have good aesthetics, biocompatibility, low thermal conductivity, abrasion resistance, and color stability. However poor resistance to fracture and shrinkage during firing process have been limiting factors in their use, particularly in multiunit ceramic restorations. A new method for making all-ceramic crowns that have high strength and low processing shrinkage has been developed and is referred to as the Vita In-Ceram method. This study was performed to investigate the effect of $CeO_2$ addition in borosilicate glasses on the strength of alumina-glass composites. Porous alumina compacts were prepared by slip casting and sintered at $1,100^{\circ}C$ for 2 hours. Dense composites were made by infiltration of molten glass into partially sintered alumina at $1,140^{\circ}C$ for 4 hours. Specimens were polished sequentially from #800 to #2000 diamond disk. and the final surface finishing on the tensile side was received an additional polishing sequence through $1{\mu}m$ diamond paste. Biaxial flexure test was conducted by using ball-on-three-ball method at a crosshead speed of 0.5mm/min. To examine the microstructural aspect of crack propagation in the alumina-glass composites, Vickers-produced indentation crack was made on the tensile surface at a load of 98.0 N and dwell time of 15 sec, and the radial crack patterns were examined by an optical microscope and a scanning electron microscope. The results obtained were summarized as follows; 1. The porosity rates of partially sintered alumina decreased with the rising of firing temperature. 2. The maximum biaxial flexure strength of 423.5MPa in alumina-glass composites was obtained with an addition of 3 mol% $CeO_2$ in glass composition and strength values showed the aspect of decrease with the increase of $CeO_2$ content. 3 The biaxial flexure strength values of alumina-glass composites were decreased with rising the firing temperature. 4. Observation of the fracture surfaces of alumina-glass composites indicated that the enhancement of strength in alumina-glass composites was due to the frictional or geometrical inter-locking of rough fracture surfaces and ligamentary bridging by intact islands of materials left behind the fracture front.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.260-267
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• 2015

We investigated the applicability of polyethylene glycol (PEG) as a plasticizer in enteric-coated soft capsules based on determination of quality characteristics according to molecular weight and concentration of enteric-coating PEG solution. There was no difference according to molecular weight of PEG, whereas a low PEG concentration in the enteric-coating solution was associated with higher whiteness index and slower disintegration time in pH 6.8 media. Brittleness was observed in the coating film at seam areas in 5% PEG enteric-coating solution after 2 weeks of storage at room temperature. The enteric-coating properties of PEG were compared with those of acetylated monoglyceride (AMG) and triacetin, which are enteric-coating plasticizers. Enteric-coated soft capsule containing PEG as a plasticizer showed a lower whiteness index and faster dissolution profile than AMG and triacetin. Moreover, enteric-coated soft capsule containing AMG and triacetin as plasticizers showed coating film brittleness at seam areas after 2 months of accelerated storage [$40^{\circ}C$, relative humidity (RH) 75%] but no difference at room temperature storage ($25^{\circ}C$, RH 60%). The present study suggests that concentration of PEG is important to determine enteric-coating quality, regardless of the molecular weight of PEG. In conclusion, PEG has potential as a plasticizer due to its transparency and storage stability in enteric-coated soft capsules.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.8
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• pp.562-570
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• 2018

New physical properties of polymer materials were obtained by blending two or three different type of polymers. TPE is used widely in the display, automotive and electronics industries. Consumers have sought emotionally more sensitive and advanced interior automotive parts. A polymer with high foamibility (Ed note: Please check this.) and flowability would be more plausible. TPE composed of foam is a good polymer material to satisfy these trends. In this research, two different TPE were tested, focusing on foamibility and flowability. Two type of TPE were prepared. The first was blended Homo-PP, oil and SEBS. The second was Co-PP, oil and SEBS. The blending temperatures were $180^{\circ}C$, $190^{\circ}C$, and $260^{\circ}C$(second one). The blending speed was 50rpm and blending time was 5 min. The MI of the blended material was affected by the MI of PP and not affected by the blending temperature. The hardness and tensile elasticity were less affected by the MI of PP and blending temperature. The hardness and tensile elasticity were lower at a higher SEBS/Oil content ratio. The soft touch feel was higher with high SEBS/Oil contents. The IPN (Interpenentration polymer network) structure was observed by dissolving the SEBS/Oil layer in xylene. Strain-hardening phenomena also was observed. TPE behaves in a rubber and foamed closed-cell improved its stability.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.860-866
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• 2000

The efforts were made to develop persimmon leaf beverages on the basis of the results of sensory evaluation. The result of sensory evaluation for the development of persimmon leaf beverages showed that when the concentration of extracts was 10%, the aroma and flavor of persimmon leaves was best. The optimum concentration of sugar was 4.5% and apple juice was 15%. The change of pH had the tendency to keep stable range(3.82-3.71) during the period of 30 days and free-sugar had little change according to the temperature and time of preservation. The preservation of the change of ascorbic acid revealed that the range of decrease in the case of preservation at $4^{\circ}C$ was a bit narrower than in the case of preservation at $25^{\circ}C$. Nonvolatile organic acids were four kinds of acids, oxalic acid, levulinic acid, malic acid, and citric acid, among which levulinic acid was on the increase for the first 10 days during the preservation period and then on the decrease regardless of the temperature of preservation. The browning of beverages was on the slight increase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1677-1685
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• 2012

The autolysate and hydrolysate of a common squid liver, Todarodes pacificus, were prepared. Autolysis (liver ratio, pH, temperature) and Protamex-treated hydrolysis (pH, temperature, ratio of protease to liver) conditions were optimized by response surface methodology using central composite design for under 1 hr of hydrolysis time. The desirability profile indicated that maximum DH could be achieved at a squid liver of 93.5%, pH 6.4, and $47^{\circ}C$ in autolysis, while that of Protamex-treated hydrolysis did at a Protamex-to-squid liver level of 0.33%, pH 6.0, and $55^{\circ}C$. Three amino acids, proline, cysteine, and methionine, were not detected in the total amino acid composition of the Protamex-treated hydrolysate, while they were detected in the free amino acid composition. Cadmium was $8.32{\pm}0.03$ mg/100 g-powder for raw, $3.56{\pm}0.02$ mg/100 g-powder for the autolysate, and $13.26{\pm}0.04$ mg/100 g powder for the Protamex-treated hydrolysate. The major molecular weight ranged from 1.0 to 1.5 kDa for the autolysate and from 210 to 470 Da for the Protamex-treated hydrolysate. Food functionalities of the autolysate, such as surface hydrolphobicity, emulsion activity index, emulsion stability, water, and fat adsorption, were similar to the Protamex-treated hydrolysate. Both the autolysate and Protamex-hydrolysate showed high inhibitory activities on the angiotensin-I converting enzyme. Cell toxicity against the HepG2 cell line was not detected in the autolysate or the Protamex-treated hydrolysate by 200 ${\mu}g/mL$.

• Culinary science and hospitality research
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• v.18 no.3
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• pp.227-238
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• 2012

This study was carried out to evaluate the effect of ${\beta}$-glucan on rheological properties of flour dough and quality characteristics of white pan bread. Flour dough and white pan bread fortified with ${\beta}$-glucans at levels of 0%, 3%, 6% and 9% w/w. Farinograph and amylograph were analysed for the rheological properties. Loaf volume and specific loaf volume, moisture content, texture and sensory evaluation were also analysed for the quality characteristics. In the farinograph test, water absorption and dough development time of doughs increased with increasing ${\beta}$-glucan content. Especially, water absorption of dough fortified with 9% of ${\beta}$-glucan showed 13% higher than the control. However, the addition of ${\beta}$-glucan to the dough decreased stability. There were no significant differences on gelatinization temperature and maximum viscosity temperature regardless of ${\beta}$-glucan contents, but maximum viscosity increased with increasing ${\beta}$-glucan contents. Loaf volume and specific loaf volume of white pan bread decreased slightly with increasing ${\beta}$-glucan contents. Moisture content showed higher value in tests than that of the control, and the one added with 6% revealed highest moisture content. In terms of texture analysis, the one added with 6% of ${\beta}$-glucan revealed softer than the others. There were no differences between the groups added with 3% and with 6% on sensory evaluation, but the one added with 9% obtained lowest scores. As a result of this study, 6% of ${\beta}$-glucan is considered the resonable level to prepare healthy white pan bread. ${\beta}$-glucan can also be used when making cake and cookies.