• Computers and Concrete
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• 제11권1호
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• pp.63-73
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• 2013

In this study, the effect of reducing cement by proportional addition of waste powder rubber on the performance of concrete under impact three-point bending loading were investigated experimentally and numerically. Concrete specimens were prepared by adding 5%, 10% and 20 % of rubber powder as filler to the mix and decreasing the same percentage of cement. For each case, three beams of $50mm{\times}100mm{\times}500mm$ were loaded to failure in a drop-weight impact machine by subjecting them to 20 N weight from 300mm height, while another three similar beams were tested under static load. The bending load-displacement behavior was analyzed for the plain and rubberized specimens, under static and impact loads. A three dimensional finite-element method simulation was also performed by using LUSAS V.14 in order to study the impact load-displacement behavior, and the predictions were validated with the experimental results. It was observed that, despite decreasing the cement content, the proportional addition of powder rubber until 10% could yield enhancements in impact tup, inertial load and bending load.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.53-56
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• 2010

In this study, we conducted an impact assessment of the amount of volatile organic solvents addition on hybrid water-proofing system of urethane waterproof coating material and modified asphalt sheet. Also, we conducted a comparative assessment of whether modified asphalt sheet is dissolved or not and oil leakage by dissolution in order to perform a comparative analysis of characteristics of the impact on modified asphalt sheet according to the volatility of volatile organic solvents included in urethane waterproof coating material. The test was carried out by adding the same amount of organic solvents into each experimental group which is subject to volatility and non-volatility of organic solvents, respectively. The results of the test showed that in both experimental groups modified asphalt sheet was dissolved when adding over 10 percent of organic solvents regardless of volatility, and oil leakage observed only in the experimental group subject to volatility.

• 한국세라믹학회지
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• 제48권1호
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• pp.74-79
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• 2011

The pore generation technology using GHM (Glass Hollow Microsphere) was studied in order to reduce the weights of porcelain. In this study, we verify the property of modified slurry by adding GHM. The modified slurry was prepared by adding 1.0~2.5 wt%(K1), 1.0~6.0 wt%(K37) of GHM to the slurry for porcelain. The slurry viscosity were stable inside a content range of 1.0~2.5 wt%(K1), 1.0~6.0 wt%(K37). However, the viscosity of modified slurry increased more than 3.0 wt%(K1) and 6.5 wt%(K37). The formed specimen by slip casting was fired at $1229^{\circ}C$, $1254^{\circ}C$. As the amount of GHM content increased, the weight decreased and the addition of 1.0~2.5 wt%(K1), 1.0~6.0 wt%(K37) of GHM resulted in a weight drop of 30%(K1) and 25(K37). However, when the GHM content increased, the strength decreases over 70%. This is caused by the presence of a large volume of surface defects (pores) and defects from the agglomeration of GHM.

• Transactions on Electrical and Electronic Materials
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• 제11권6호
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• pp.288-291
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• 2010

Accidents can occur as a result of streaming electrification when transformer oil is used as an insulating oil in large ultra-high voltage transformers. Methods for adding a streaming electrification inhibitor to reduce the streaming electrification has been studied extensively. In this paper, in order to develop a method for reducing streaming electrification effectively, 4 different specimens were prepared by the addition of benzotriazole (BTA) to a virgin specimen with constant stirring. The specimens were examined to determine the appropriate amount of BTA addition that would suppress the streaming electrification most effectively. The results showed that the streaming electrification characteristics of the specimen in the streaming transformer oil were best when the amount of BTA addition was about 10 ppm. The streaming electrification current was reduced by adding 30 ppm BTA until the temperature reached $65^{\circ}C$. The polarity of the streaming electrification current was negative when the temperature exceeded $65^{\circ}C$. Therefore, the streaming electrification current, which can be a cause of transformer accidents, can be suppressed in large ultra high voltage transformer oil. This paper reports on the optimal amount of BTA addition and the best conditions for controlling the streaming velocity of transformer oil.

• 동아시아식생활학회지
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• 제16권3호
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• pp.357-363
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• 2006

This study examined the effect of medicinal herbs on the growth of 3 strains of lactic starter cultures in a MRS broth by adding a 0, 1, 3, 5, and 10% water extract. The pH, titratable acidity and OD of lactic acid bacteria were investigated in order to obtain fundamental knowledge for the development a new product, box thorn yogurt. In the case of adding the Acanthopanax sessiliflorum Seeman water extract, Streptococcus thermophilus was largely activated by the addition of the 5% extract. The growth of Lactobacillus acidophilus was activated by the extracts but it was depressed by the addition of the 3% Acanthopanax sessiliflorum Seeman water extract. Compared with the control, the growth of Bifidobacterium longum was largely activated by the addition of the 10% extract but it was depressed by the addition of the 5% Acanthopanax sessiliflorum Seeman water extract.

• Elastomers and Composites
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• 제51권3호
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• pp.175-180
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• 2016

Influence of amino acidic chemical on properties of maleic anhydride-grafted ethylene-propylene-diene terpolymer/zinc oxide (EPDM-g-MAH/ZnO) composites was investigated. 4-Aminosalicylic acid (ASA), 4-amino-2-methoxybenzoic acid (AMBA), 12-aminolauric acid (ALA), and glutamine (Gln) were employed as the amino acidic chemicals. Though small quantity (0.5 phr) of the amino acidic chemical was added to the EPDM-g-MAH/ZnO composite, the properties were notably changed. By adding the amino acidic chemical, the percent crystallinity and apparent crosslink density were reduced. Order of the percent crystallinity was related to that of the $pK_a$ values of amino acidic chemicals. By adding the amino acidic chemical, the basic tensile properties were on the whole improved. The experimental results were explained by the $pK_a$ values of amino acidic chemicals, change of zinc ionomer formation, and interactions between the additive and EPDM-g-MAH chain.

• 한국식품조리과학회지
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• 제29권6호
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• pp.733-739
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• 2013

This study investigates the characteristics of mayonnaise adding yuza juice, a byproduct of yuza tea, to it. The mayonnaise was prepared by adding yuza juice at 0(control), 25, 50, 75, 100%. In order to analyze the characteristics of the mayonnaise, we examined the color, viscosity, emulsion stability and sensory acceptability. The L, a, ${\Delta}E$ values of mayonnaise mixed with yuza juice were similar to or lower than control. As the content of yuza juice increased, the viscosity and emulsion stability, that is the physical quality of the mayonnaise, improved significantly(p<0.05). With regard to sensory evaluation, mayonnaise mixed with yuza juice had better flavor, taste, texture and overall acceptability(p<0.05). These results suggest that yuza juice is good ingredient to improve the quality and sensory acceptability of mayonnaise.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권1호
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• pp.16-22
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• 2005

cDNA for oxidosqualene cyclase was cloned by a homology-based PCR method and sequenced from Centella asiatica. In a sequences analysis, the putative polypeptide of C. asiatica cycloartenol synthase (CaCYS) deduced from the 2,274 bp nucleotide sequence, consisted of 758 amino acids and had a molecular mass of 86.3 kD. The predicted amino acid sequence exhibited high homology to that of PNX (cycloartenol synthase) from Panax ginseng ($89\%$). Southern blot analysis suggests that CaCYS may be present in one copy of the C. asiatica genome. If methyl jasmonate (MJ) is applied exogenously to plants, not only triterpene saponins are accumulated in tissues, but also it produces effects such as growth inhibition and the promotion of ethylene production. In order to investigate the effect of MJ and thidiazuron (TDZ), a cytokinin that plays a role as an antisenescence agent in several plants, on the level of CaCYS mRNA, we performed northern blot analysis. When MJ is alone treated by adding to culture medium, CaCYS transcripts were inhibited. However, sustained levels of the expression of CaCYS, by adding TDZ to the medium despite MJ treatments, were demonstrated in C. asiatica leaves.

• Journal of Pharmaceutical Investigation
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• 제3권3호
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• pp.5-15
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• 1973

The stabilizing effect of promazine hydrochloride injectin was tested by irradiation of sun lamp(5,000 Lux) on their acid solution sealed in ampules under various stabilizers. The result of experimentation on the color change, the remaining proportion and the half life of promazine hydrochloride solution is as follows. 1. Instability of promazine hydrochloride solution is mainly caused by the sunlight and oxygen. 2. The pH range of promazine hydrochloride injection is recommended to $pH\;4.4{\sim}5.2$ 3. The decomposition of promazine hydrochloride by the sunlight is composed of pseudo zero order reaction when It maintains colorless solution. 4. The half life of 0.5% promazine hydrochloride injection was 30 hrs. under sun lamp irradiation, but it was delayed to 84 hrs. by the simple stabilizer and to 175 hrs. by compound stabilizer. 5. The stabilizing effect of promazine .hydrochloride injection adding sod. metabisulfite$(Na_2S_2O_5)$ was most excellent in various simple stabilizers and adding $Na_2S_2O_5$ to nicotinic acid, $Na_2S_2O_5$ to nicotinamide were more excellent than other compound stabilizers.

• 한국응용과학기술학회지
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• 제24권1호
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• pp.86-91
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• 2007

Gasohol, which is combined solution of gasoline and ethanol, is difficult to apply to the field, because it usually brings phase separation by mingling of water. We investigated phase separation by adding different concentrations of "Ethanol", anhydrous and fermentative, to "Gasolines", gasoline, gasoline base and naphtha, Placing ethanol itself open to the air, the concentrations of water are increased in length of time. The phase separation temperatures of the gasolines-ethanol solutions have dropped in the following order : gasoline, gasoline base and naphtha. When adding water to the solutions of gasolines and anhydrous ethanol, the temperatures of phase separation is higher when the concentration of water increases more. Thus, it is obvious that the water is sensitive in phase separation.