• Journal of the Korean Ceramic Society
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• v.27 no.7
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• pp.861-868
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• 1990

Investigation for the preparation of high strength hardened cement paste using ordinary portland cement, hydroxypropyl methyl cellulose(HPMC) with SiC powder was carried out. The cement paste was mixed with 0.1 of water cement ratio by twin roll mill and cured 60 days in humidity chamber. The hydration degree of cement paste cured with W/C=0.1 in 60 days was about 30% and most pores in the paste were found to be existed as gel pores of diameter less than 0.01㎛. The maximum flexural strength of hardened cement paste was about 960kg/㎠. When the SiC powder was added to the paste, the flexural strength was 1000∼1100kg/㎠ and the Young's modulus was 8∼9×105kg/㎠.

• Korean Journal of Medicinal Crop Science
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• v.27 no.4
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• pp.247-258
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• 2019

Background: Astragali radix (A) and Lithospermi radix (L) have long been used as traditional medicines due to their known anti-inflammatory effects. This study aimed at evaluating, their optimal mixing ratio and their functional compounds by investigating the inhibitory effects of mixed extracts of A and L and their active compounds on matrix metalloproteinases (MMPs). Methods and Results: A and L extracts were obtained by extraction at $80^{\circ}C$ using 50% and 70% fermented alcohol, respectively, and then mixed at a ratio of 5 : 5, 6 : 4, 7 : 3 and 8 : 2 (w/w). The activities of MMP-1, MMP-3, and MMP-13 were evaluated in interleukin-1beta ($IL-1{\beta}$)-induced SW1353 cells. The extract mixtures showed synergistic inhibitory effects on MMP-3 and MMP-13, higher than the effects of the individual A and L extracts. The 7 : 3 mixture (ALM16) showed the most effective MMPs inhibitory activity, while among the active ingredients, calycosin-7-O-${\beta}$-D-glucoside and lithospermic acid exhibited excellent MMPs inhibitory activity. Additionally, an HPLC method was established for simultaneous quantification of the effective components of the extract mixtures, and validated by measuring the linearity, precision and accuracy of the limit of detection (LOD) and limit of quantification (LOQ). Conclusions: ALM16 showed the most effective MMPs inhibitory activity. Calycosin-O-${\beta}$-D-glucoside, calycosin and lithospermic acid were identified as useful candidates, as they were the major functional compounds in the MMP inhibitory activity. Summarily, ALM16 might be a highly effective in osteoarthritis management, owing to its because it exhibits a protective effect on cartilage via excellent inhibition of MMPs.

• Korean Journal of Food Science and Technology
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• v.7 no.2
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• pp.96-99
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• 1975

In order to establish an optimal flour milling method for naked barley, the tempering conditions, milling after pearling and mixed flour milling of naked barley with wheat were studied, and the following results were obtained. 1. For the tempering of naked barley, treatment for 48 hours at a moisture level of 13. 5% and addition of 0. 5% water prior to the flour milling is the most useful procedure. 2. The pearling of naked barley before or after tempering lowers the ash content in the flour, but the yield is reduced considerably and two steps of processing make the procedure unsuitable. 3. For the mixed flour milling, the mixing ratio of naked barley to wheat ranging from 10 : 90 to 20 : 80 is optimal.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.260-268
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• 2018

The aim of this study was to evaluate the effect of light quality using either monochromatic or combined LEDs on the growth and antioxidant accumulation of Agastache rugosa cultivated under hydroponics for 4 weeks. This experiment was performed in a controlled-environment room at $22{\pm}1^{\circ}C$ and $18{\pm}1^{\circ}C$ (day and night temperatures, respectively) and 50-70% relative humidity, with a provided photosynthetic photon flux density (PPFD) of $180{\pm}5{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and irradiated with either monochromatic (W10 and R10) or mixed LEDs (W2B1G1, R3B1, R2B1G1, and W2B1G1) with a differing ratio of each LED's PPFD and fluorescent lighting (FL: control) with a 16/8 h photoperiod. Fresh and dry weights were highest for plants grown under the W2B1G1 treatment. A. rugosa grown with R10 had the greatest plant height but the lowest SPAD among all treatments. The concentration of rosmarinic acid in plants grown under W2B1G1 was significantly higher than that of plants grown under other treatments. Tilianin content was significantly higher in R3B1 than in the other treatments. However, whole-plant rosmarinic acid and tilianin content was the highest under the W2B1G1 condition. To cultivate A. rugosa in a plant factory, mixed-LED light conditions with W2B1G1 is considered to be more advantageous for the growth and antioxidant accumulation of A. rugosa. It is though that the total whole-plant antioxidant content is more crucial for commercial use; the present study demonstrates the potential to achieve higher content of functional materials in plants through the selection of light quality.

• International Journal of Concrete Structures and Materials
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• v.11 no.1
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• pp.59-68
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• 2017

Mercury intrusion and nitrogen sorption porosimetry were employed to investigate the pore structure of calcium sulfoaluminate ($C{\bar{S}}A$) and portland cement pastes with cement-to-water ratio (w/c) of 0.40, 0.50, and 0.60. A unimodal distribution of pore size was drawn for $C{\bar{S}}A$ cement pastes, whereas a bimodal distribution was established for the portland cement pastes through analysis of mercury intrusion porosimetry. For the experimental results generated by nitrogen sorption porosimetry, the $C{\bar{S}}A$ cement pastes have a smaller and coarser pore volume than cement paste samples under the same w/c condition. The relative dynamic modulus and percentage weight loss were used for investigation of the concrete durability in freeze-thaw condition. When coarse aggregate with good freeze-thaw durability was mixed, air entrained portland cement concrete has the same durability in terms of relative dynamic modulus as $C{\bar{S}}A$ cement concrete in a freeze-thaw environment. The $C{\bar{S}}A$ cement concrete with poor performance of durability in a freeze-thaw environment demonstrates the improved durability by 300 % over portland cement concrete. The $C{\bar{S}}A$ concrete with good performance aggregate also exhibits less surface scaling in a freeze-thaw environment, losing 11 % less mass after 297 cycles.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.5
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• pp.53-67
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• 2011

The major objective of this study was to quantify the effects of substrate depth and substrate composition on the development of sedum etc., in a sloped rooftop (6 : 12 pitch) environment during a 4-year period. The experiment was conducted from 2006 October to 2010 December under several conditions without soil erosion control : two substrate depth (5cm, 10cm), four substrate composition (A5N3C2, A3N3C4, A6C4, G5L3C2: A: artificial lightweight soil, N : natural soil, G : granite decomposed soil, C : leave composite, L : loess), four sloped roof direction ($E40^{\circ}W$, $W40^{\circ}N$, $S40^{\circ}W$, $N40^{\circ}E$). In this experiment 4 sedum etc., were used: Sedum sarmentosum, Sedum kamtschaticum, Sedum rupestre, Sedum telephium, flowering herbs (mixed seed : Taraxacum platycarpum, Lotus corniculatus, Aster yomena, Aster koraiensis), western grasses (mixed seed : Tall fescue, Creeping redfescue, Bermuda grass, Perennial ryegrass). The establishment factor had two levels : succulent shoot establishment (sedum), seeding (flowering herbs, western grasses). 1. Enkamat, as it bring about top soil exfoliation, was unsuitable material for soil erosion control. 2. Sedum species exhibited greater growth at a substrate depth of 10cm relative to 5cm. All flowering herbs and western grasses established only at a substrate depth of 5cm were died. A substrate depth of 5cm was not suited in sloped rooftop greening without maintenance. If additional soil erosion control will be supplemented, a substrate depth of 10cm in sloped rooftop greening without maintenance was considered suitable. 3. For all substrate depth and composition, the most abundant species was Sedum kamtschaticum. The percentage of surviving Sedum kamtschaticum was 73.4% at a substrate depth of 10cm in autumn 2007 one year after the roof vegetation had been established. But the percentage of surviving other sedum were 33.3%~51.9%, therefor mulching for soil erosion control was essential after rooftop establishment in extensive sloped roof greening was proved. To raise the ratio of plant survival, complete establishment of plant root at substrate was considered essential before rooftop establishment. 4. There was a significant interaction between biomass and substrate moisture content. There were also a significant difference of substrate moisture and erosion among substrate composition. The moisture content of A6C4 was highest, the resistance to erosion of A5N3C2 was highest among substrate composition. The biomass of plants were not significantly higher in A5N3C2 and A6C4 relative to A3N3C4 and G5L3C2, For substrate moisture and erosion resistance, A5N3C2 and A6C4 were considered suitable in sloped rooftop greening without maintenance. 5. There were significant difference among roof slope direction on the substrate moisture. Especially, the substrate moisture content of $S40^{\circ}W$ was lower relative to that of $N40^{\circ}E$, that guessed by solar radiation and erosion.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.1
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• pp.69-75
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• 1988

Two rational formulae depicting the relationships between sludge ages and recycle flow rates have been developed to determine sludge wasting volumes at a particular sludge age. A sensitivity analysis shows that the recycle ratio is the most important variable to be measured as accurately as possible in determining the sludge wasting volume to maintain a particular sludge age when the system is controlled by wasting recycled sludge. On the other hand, the final clarifier solids capturing capacity is the most important variable to be measured when the system is operated by wasting mixed liquor.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.451-455
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• 1990

The extrusion characteristics of pork rind mixed with corn flour were investigated. The blends of pork rind to corn flour in the ratio of 1 : 2, 1 : 1, 2 : 1 and 3 : 1(w/w) were made and each blend was dried up to 5, 10 and 15% moisture content. The blends were extruded by single screw extruder. The extrusion characteristics of each extrudate were as follow. The highest value of expansion ration was attained by mixing pork rind and corn flour in the ratio of 1 : 1, containing 5% moisture content. As the rind content to the corn flour mixture was increased, the bulk density, water absorption index, breaking stregth and redness, of the extradate increased, but the lightness and yellowness decreased. It was concluded that a high quality snack food could by produced by extrusion-cooking the mixture of pork rind and corn flour.

• Applied Biological Chemistry
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• v.46 no.4
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• pp.367-375
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• 2003

The puree of Rubus coreanus was fermented using lactic acid bacteria and its biological activities were examined. Lactobacillus acidophilus KCCM 32820, L. casei KCCM 12452, Lactococcus lactis subsp. lactis KCCM 40104, and Streptococcus thermophilus KCCM 40430 were used as a single or mixed starter for the lactic acid fermentation, and their cultures at the late logarithmic growth phase were inoculated to final concentration of 2% (v/v). L. casei fermented the puree of Rubus coreanus best when used as a single starter, and the culture of L. casei and L. lactis with the inoculation ratio of one to one showed the highest fermentation activity when used as a mixed starter. However, the fermented broth of the puree of Rubus coreanus using L. acidophilus and S. thermophilus showed the best results in the sensory evaluation. The optimal lactic acid fermentation conditions were as follows; the concentration of oligosaccharide added was 1% (w/v), pH of puree and fermentation temperature were 4.0 and $37^{\circ}C$, respectively, and fermentation time was $72{\sim}96$ hours. Glucose and fructose were major free sugars, and the content of lactic acid was 698.2 mg/100 g in the fermented broth. The fermented broth of the puree of Rubus coreanus showed the electron donating ability and nitrite scavenging ability with the value of 69% and 38.3% at pH 1.2, respectively. SOD-like activity and inhibitory activity on xanthine oxidase were also found in the fermented broth with the value of 60.3% and 41.8%, respectively. When the antimicrobial activities of the fermented broth were examined, it showed the highest growth inhibitory activity against Escherichia coli O-157:H7, and also contained antimicrobial activities against Salmonella typhimurium, Bacillus cereus, and Staphylococcus aureus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.143-148
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• 2007

This study was to investigate the mixed buckwheat flour quality by observing antimutagenic and cytotoxic effects of mixed buckwheat flour extracts using Ames test and SRB (sulforhodamine B) assay. Samples were prepared to the ratio of 100% (B1), 90% (BF1), 80% (BF2), 70% (BF3) and 60% (BF4) (w/w) flour buckwheat based on wheat flour weight. The initial pasting temperature in an amylograph was increased according to the increase of the buckwheat flour. The water absorption in farinograph decreased with the addition of buckwheat flour. The inhibition rates of B1, BF3 and BF4 extract (160 g/plate) were 45%, 37.3% and 42% against the mutagenesis of Salmonella Typhimurium TA100 induced by MNNG $(0.4{\mu}g/plate)$, respectively. In addition, the B1 at the same concentration showed 64% and 44.3% inhibition on the mutagenesis of Salmonella Typhimurium TA98 and TA100 induced by 4NQO $(0.15{\mu}g/plate)$, respectively. In SRB assay, human breast adenocarcinoma (MCF 7), human hepatocellular carcinoma (Hep3B), human stomach adonocarcinoma (AGS), human lung carcinoma (A549) and human cervical adenocarcinoma (HeLa) proliferations were inhibited by the increase in the sample concentration.