This work aims the search of environmentally friendly pre-treatment technologies to develop chromate replacements for metal finishing industries due to its toxicological properties. Since the corrosion resistance of steel was strongly related to water permeation, galvanized steel sheets were treated with various hydrophobic silane compounds and water-suspended polymer solution. Also, plasma gas discharge was applied to modify the surface of a polymer coated-steel sheet to be hydrophobic. The surface hydrophobicity of materials was introduced by CF3H plasma exposure. The corrosion property before and after the plasma treatment was investigated in a slat spray tester with 3.5 wt.% NaCl at 35 ℃. The results showed that both silane/polymer double coatings and plasma treatment of the galvanized steel exhibited significant retardation of corrosion.

기능성 발효음료를 개발하기 위하여 홍차, 감잎차, 솔잎, 쑥, 눈꽃 동충하초와 번데기 동충하초의 균사체와 자실체를 부재료로 첨가한 배지에 tea-fungus를 접종하여 3에서 2주일간 발효시킨 tea-fungus 음료를 조제하였다. Tea-fungus 음료의 기능성을 조사하기 위하여 음료의 원액과 그 5배 희석액으로 나누어 항균활성, 항산화능과 아질산염소거능을 조사하였다. Tea-fungus 음료의 항균활성은 솔잎과 눈꽃동충하초의 균사체와 자실체

백년초 분말을 각각 0%, 0.05%, 0.1%, 0.3% 및 0.5%의 비율로 첨가한 국수를 제조하여 일반성분, 수분함량, 색상 및 기계적 texture를 측정하고 관능검사를 행하였다. 백년초 첨가 국수의 수분함량은 모두 32∼33% 정도로 큰 차이가 없었다. 국수 대조구의 색상은 명도(L치) 74.21,적색도(a치) -2.40, 황색도(b치) 5.52였으며 백년초 분말 첨가량이 증가할수록 명도(L치)는 감소하며, 적색도(a치)와 황색도(b치)

키토산이 백설기의 품질특성에 미치는 영향을 조사하기 위하여 0~0.5%의 키토산을 첨가한 백설기를 제조한 후 백설기의 저장성, 물성 및 관능적 품질특성을 조사하였다. 백설기의 pH는 대조구가 5.65이었으며 0.05~0.5%의 키토산 첨가군은 pH 7정도였다. 백설기의 색상은 멥쌀 100%인 대조군은 명도(L치) 84.28, 적색도(a치) -1.56, 황색도(b치) 7.68 이었으며, 키토산 첨가에 의해 명도, 적색도, 황색도가 모두 높아지는 경

쑥과 솔잎을 각각 물과 70% 에탄올로서 추출하여 전자공여능과 아질산염 소거능을 조사하였다. 쑥 추출물의 전자공여능은 300-1,000ppm 농도에서 물추출물은 50-57%였으며, 에탄올추출물은 51-64%로서 에탄을 추출물이 우수하였다. 솔잎 추출물의 전자공여능은 물추출물은 100-500ppm에서 52-60%, 1,000ppm에서는 70%의 전자공여능을 나타내었으며 에탄을 추출물은 100-500ppm에서 68-71%, 1,000ppm에서는 약

인공재배한 번데기동충하초의 균사체와 자실체를 각각 물과 70% 에탄올로서 추출하여 전자공여 능과 아질산염 소거능을 조사하였다. 균사체 추출물의 전자공여능은 300∼1,000 ppm의 물추출물에서 37∼47%였으나, 에탄올추출물에서 57∼70%로서 에탄을 추출물이 우수하였다. 자실체 추출물의 전자공여능은 300∼1,000 ppm에서 물추출물과 에탄올추출물 모두 19∼48%로서 균사체 추출물에 비하여 낮은 편이었다. 아질산염 소거능은 pH 1.2,

동충하초(눈꽃 동충하초, 번데기 동충하초), 쑥 및 솔잎 추출물의 항균작용을 조사하기 위하여 동충하초의 자실체와 균사체, 쑥 및 솔잎을 물과 70% 에탄올로 추출하였다. 항균실험에는 3종류의 그람양성균(Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus)과 3종류의 그람음성(Escherichia coli, Shigella sonnei, Salmonella typhimurium) 식중

키토산을 각각 0% (Co), 0.05%(A), 0.1%(B), 0.3%(C), 0.5%(D)의 비융로 침가하여 백설기를 제조하여 키토산 첨가에 따른 백설기의 품질특성과 저장성을 조사하였다. 백설기의 품질특성은 pH, 수분함량, 색상, 기계적 texture를 측정하고 관능검사를 행하였으며 백설기의 저장성은 . 에서 저장중 생균수의 변화를 조사하였다. 키토산을 첨가하지 않은 대조구의 pH는 5.65로 산성 올 나따낸 편이나 키토산 첨가군은 모두 p

Water extract of green tea(GTW) and 70% ethanol extract of green tea(GTE) were prepared for the test of antibacterial activity. The sensitivity of Staphylococcus aureus and Salmonella typhimurium to the green tea extracts in various pH of culture broth was tested. Tryptic soy broth(TSB) containing 0∼2%(w/v) of green tea extracts was adjusted to pH 5.0∼7.0 and inoculated with 105/∼106/ cells/ml of each bacteria. The plate counting method and clear zone test were used to determine inhibitory effect of green tea extracts. Green tea extracts completely inhibited the growth of S. aureus at 0.5% level and bactercidal at 0.5∼1.0% level of GTW and GTE at pH 5.0∼7.0. Green tea extracts were bactercidal to S. typhimurium at 1.5∼2.0% level of GTW and 1.0∼2.0% level of GTE at pH 7.0. Sal. typhimurium was more resistant than S. aureus. in same concentration of green tea extracts at same pH. The resistance of S. aureus and Sal. typhimurium was increased with decreasing pH of culture broth. The morphology of S. aureus cells treated with green tea extracts showed damage of cell wall and cytoplasmic membrane. Severely damaged cells of S. aureus lost electron dense material and cytoplasm. Green tea extracts stimulated autolysis and cell death of S. aureus. This result suggests that green tea extracts can be used as an effective natural antibacterial agent in food.

여러 가지 담자균 자실체의 물과 methanol 추출물을 이용하여 5가지 식중독균에 대해 항균실험을 실시한 결과, 석이버섯, 상황버섯, 영지버섯 추출물에서 항균활성이 있었으며, 석이버섯 methanol 추출물이 가장 높은 항균력을 나타내었다. 높은 항균력이 확인된 석이버섯, 상황버섯의 80% methanol추출물을 diethylether, chloroform, ethyl acetate, n-butanol, 물의 순으로 분획물을 얻어서 항균 및 항

This study examined blends of styrene butadiene rubber(SBR) and chloroprene rubber(CR) prepared from an open 2-roll mill following the conventional polymer blend method for a wide range of the blend composition. Rubber vulcanizates were manufactured by hot press and then mechanical properties, heat and ozone resistance of the specimens were examined. Due to the post cure during the aging test, hardness of vulcanizates was increased. It was found that the undesirable characteristics of heat and ozone resistance of pure SBR was significantly improved through the blending of SBR with CR.

The purpose of this experiment is to prepare ethylene propylene diene terpolymer(EPDM)/acrylonitrile butadiene rubber(NBR) blend which represents good environmental resistant properties including favorable oil and ozone resistance. With incorporation of EPDM, NBR and other ingredients, the rubber and chemical additives were mixed by mechanical method such as Banbury mixer and open 2-roll mill. Then rubber vulcanizates were manufactured by hot press and mechanical properties, oil and ozone resistance of the test specimens were measured. The oil resistance and ozone resistance of EPDM and NBR, respectively, is remarkably improved by blending EPDM with NBR. The optimum results of oil and ozone resistant characteristics were obtained at EPDM/NBR(=25/75 wt%) composition ratio.

Nitrate-selective ion exchange resin which have bulky tertiary amine as functional group have been synthesized by the reaction of chloromethylated polystyrene-divinylbenzene copolymer and the corresponding tertiary amine [NR3=NEt3 1, N(C2H4OH)3 2] in ethanol, while commercial resin has NMe3 as functional group. The fundamental properties such as bulk density, water content, appearance index, exchange capacity, effective size, uniformity coefficient of synthesized anion exchange resin (1) have been measured. The ion exchange resin (1) and (2) exhibited the better selectivity for nitrate than sulfate in both batch and continuous column experiments.

Antibacterial activities of powdered spices(garlic , ginger, cinnamon and clove) against pathogenic Escherichia coli )157:H7 and Staphyloccus auresus were investigated. Spice powder was added in was exponetial phase of each bacterial culture . Growth inhibition was determined by the absorbance at 660nm and morphological changes of the cells were observed by transmission electron microscope (TEM). Ginger powder has the highest antibacterial activity, following cinnamon , clove and garlic has the least activity.Growth of Escherichia coli O157:H7 and Staphyloccus aureus were completely inhibited within 5 hours after addition of 1 % of garlic , 0.3% of ginger or cinnamon , 0.5% of clove powder on the exponential phase of the cells. Spice untreated cells of E. coli and S. aureus, the cytoplasm was entirely surrounded by rigid cell wall and cell walls formed a smooth layer well attached to the plasma membrane. In the cells of E. coli and S. aureus treated with spice powder, cell wall and plasma membrane were lysed and severely damaged. E.coli cells growth in the presence of spice powder showed plammolysis, the loss of electron dense material, the formation of extra cellular blebs and cytoplasm burst out from the cell. S .sureus cells grown in the presence of spice powder showed swell of cell wall, the loss of electron dense material , coagulation of cell cytoplasm and formation of extra cellular blebs. Severely damaged cells of S. aureus lost whole cytoplasm and left as ghost of the cell. Spice powder stimulated autolyssi and induced cell death.

N-Methylpurine-DNA glycosylase (MPG)는 DNA에서 N-methylpurine과 다른 손상된 purine기를 제거하는 DNA 회복 효소이다. 생쥐의 임신 8일 후의 태아조직부터 생후 400일까지의 조직들로부터 RT-PCR 방법으로 MPG mRNA 발현을 조사하였다. MPG mRNA는 태아 형성기동안 많은 양이 발현되었으며, 특히 15일에서 가장 높게 발현되었다. 태반에서의 MPG mRNA는 8 p.c. (post coitum)