• Proceedings of the Membrane Society of Korea Conference
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• 2002.05a
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• pp.172-173
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• 2002

• The Research Journal of the Costume Culture
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• v.12 no.2
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• pp.279-289
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• 2004

This study was conducted to compare the hunting reaction of finger in the cold water. Finger skin temperature is measured the left middle finger tip immersion in cold water of 5℃ for 30 minutes and measurements were made on finger skin temperature(Ts), thermal comfort, and cold pain sensations during the experiment at the spring (March) and Winter(December). Results were follows. Is before immersion was at the highest in spring and at the lowest in winter and was closely related to the indoor temperature Ts during immersion and recovery. Mean of finger skin temperature(MST), the skin temperature at the first rise(TTR) and amplitude of finger skin temperature reaction during immersion(AT) were significant higher in spring than that in winter(P＜.01). The lowest skin temperature(LST) during the cold water immersion were significantly higher in spring than that in winter (P＜.05). The frequency of the appearance of cold-Induced vase dilation(CIVD) was higher in spring than that in winter. However, time for the first temperature(TTR) and recovery time(RT) had no seasonal variation. In addition, cold pains during immersion were felt more strongly in spring than in winter. Local thermal sensation, finger thermal sensation in dynamic state during hand immersion was different from that in the Winter. Spring was slowly cold in cold water immersion.

• Korean Journal of Environment and Ecology
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• v.15 no.2
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• pp.173-185
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• 2001

마편초과의 좀목형 엽에 함유된 물질의 allelopathy 효과를 구명하기 위해 수용성 엽 추출액, 메탄올 엽 추출액, 엽 분말과 토양과의 혼화된 pot에 각각 상치, 이탈이란라이그라스, 개솔새, 억새 종자를 발아실험하여 발아억제물질을 분석한 결과는다음과 같다. 1. 좀목형 엽 분말을 증류수에 각각 24, 48, 72 시간 침지 후 추출물에 상치, 이탈리안라이그라스, 개솔개, 억새 종자를 파종한 후의 발아율은 각 처리구마다 대조구마다 높은 발아억제를 보였고, 48시간 침지시에는 각각 26.9%, 58.8%, 6.6%, 22.2%의 발아율을 보여 강한 발아억제현상르 보였다. 2. 좀목형 엽 분말을 메탄올 75%에 24, 48시간 침지 후 추출물에 이탈리아라이그사스, 개솔새, 억새 종자를 파종한 후의 발아율은 48시간 추출액때 각각 33.3%, 15.4%, 7.7%를 보여 48시간 수용성 추출액과 24시간 메탄올 추출액보다 강한 발아억제효과가 있었다. 3. 좀목형 엽 분말과 Vermiculite를 1: 99.5: 95, 10:90, 20:80(w/w)으로 구분한 pot에 공시수종을 파종한 결과 엽 분말의 비율이 높을수록 발아억제효과가 컸으며, 엽 분말이 20%인 경우 발아된 부분의 건중량의 비율은 실험구와 대조구간에 비교한 발아율의 비율보다 훨씬 낮아 생장억제효과가 있는 것으로 나타났다. 4. Column chromatography의 TLC를 이용하여 최종 7 fraction을 찾고 생물검정 결과, 5, 6번 fraction에 강한 활성을 나타냈다. 5. UV 와 IR분광분석 결과 UV 분광분석은 256 nm과 336nm에서 흡수 최대를 나타내었으며, 이들은 시르시트시약을 사용하여 검토한 결과 7위에 에테르 결합한 전형적인 플라본류로 추정되었고, IR 분광분석 결과 지방족에 에테르결합이 존재하는 것으로 생각되었다. 6. Py-GC-MS 분석으로부터 5, 6 fraction의 경우 플라본류에 1개의 당이 결합한 배당체 구조이고 B환의 경우 1개 또는 2개 이상의 페놀성 수산기의 존재가 예상되었다.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.153-160
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• 2011

In this study, we have developed taste and other functional enhancements of yam chips, from tasteless and flavorless yam slices, through the process of soaking freeze-dried yam in different commercially available juices, including apple, omija (fruit of Maximowiczia typica), grape, wild grape, orange, tomato, red ginseng, and black garlic juice. The analyses of color (brightness, redness and yellowness), pH, brix, acidity, total polyphenol, total flavonoids, total sugar and reducing sugar, DPPH and ABTS scavenging activity, reducing power and nitrite scavenging activity, of the different yam chips showed that the freeze-dried yam slices absorb various components of fruit juices, such as flavonoids, sugars, organic acids and flavors, during the soaking process. These changes resulted in increased taste (both sweet and sour tastes), flavor and antioxidant activity in the yam chips. The soaking time for yam slices in juice is considered to be a crucial factor for the taste and bioactivity of yam chips. In the case of grape juice-yam chips, which had the highest preference among the 8 different chips, the optimum soaking time was noted as 120 seconds. The optimization of the soaking process is necessary for various juices. These results suggest that taste, and other functional enhancements, in yam chips can be developed by juice-soaking and freeze-drying methods.

• Journal of the Korean Wood Science and Technology
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• v.27 no.3
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• pp.39-50
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• 1999

This research was carried out to investigate the development of fire-retardancy treatment technology and performance evaluation of fire-retardant treated plywoods. Radiata pine, keruing, dillenia, calophyllum and terminalia veneers were treated by normal(conventional) pressure soak(NPS) and vacuum-pressure-soak(VPS) using 20% water solution of diammonium phosphate. Then, 4.8mm thick, 3ply plywoods were fabricated with combination of fire-retardant treated, untreated or water-immersion types and several composition types of radiata pine and keruing veneers, i,e. the uniform and the mixed types in species composition, and the homogenious and the alternate layer types in veneer treatment. In composed species, the retention and the treatment effects of fire-retardant chemicals III radiata pine was still greater than those of keruing. The effect of VPS treatment was larger than that of NPS treatment, however, adhesive bonding strength and bending strength of plywoods treated by these two methods were not necessarily lowered, compared to those of untreated plywood. And also, fire endurance performance of the urea melamine resin-bonded plywood was greater than that of the phenol resin-bonded plywood. In result, the appropriate combination in veneer species and layer as well as alternate fire-retardant treatments would be more efficiently available in service.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.476-481
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• 1997

For the effect of water-soluble degraded chitosan on the shelf-life of tofu, sterilized distilled water, 0.5% degraded chitosan, 0.5% fumaric acid and 0.5% lactic acid used as an tofu-immersion solutions were investigated by microbial counts, pH, and turbidity during the periods of storage at $4^{\circ}C$. After 2 weeks storage, total aerobic microbial counts in tap water and sterilized distilled water used as an immersion solution were $3.8\;{\times}\;10^8$ and $1.8\;{\times}\;10^8\;CFU/mL$, respectively. In 0.5% fumaric acid and 0.5% lactic acid immersion solutions, the microbial counts were around $10^7\;CFU/mL$ after 2 weeks while the microbial population in 0.5% water-soluble degraded chitosan were, however, $1.6\;{\times}\;10^5\;CFU/mL$ after 2 weeks and $1.7{\times}10^7\;CFU/mL$ after 3 weeks. The lag phase of initial contaminated microbes in 0.5% degraded chitosan solution was longer than those of other treatments. The addition of 0.5% fumaric acid and 0.5% lactic acid decreased the initial pH to pH 5.0, while those of tap water, sterilized distilled water and 0.5% degraded chitosan stabilized the immersion solution at around pH 7.2. All initial pH values were decreased during storage and then slowly increased as storage time was increased. The turbidities in all treatments were increased during storage, but the addition of 0.5% degraded chitosan showed the lowest change, compared to other treatments, showing that the water-soluble degraded chitosan has a good antimicrobial effect and has a potential use to extend the shelf-life of tofu product.

• Resources Recycling
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• v.21 no.4
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• pp.53-59
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• 2012

In this study, behaviors of removing Sb and Pb by oxidation of molten Bi-Pb-Sb alloy which is a by-product of non-ferrous smelting process was investigated. The molten alloy was oxidized at 1173 K by bubbling $N_2+O_2$ gas through a submerged nozzle. The Sb was removed and recovered as mixed phase of $Sb_2O_3$ and metal Sb. In the case of bubbling $N_2+O_2$ gas into molten Bi-Pb alloy at 923 K, Pb was oxidized and removed to slag. But Bi could not be refined due to simultaneous oxidization of Bi with Pb.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.1
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• pp.73-81
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• 2010

The objective of this study was to evaluate the color stability of new silorane-based composite resin compared with methacrylate-based composite resins after immersion in 3 staining solutions. One silorane-based composite(Filtek P90) and 3 methacrylate -based composites(Filtek Z250, Filtek Z350, Tetric Ceram) were evaluated. Twenty disk-shaped specimens($10{\times}2mm$) of each of 4 composite resins were prepared. The specimens were then divided into 4 groups of 5 specimens each and immersed in 3 staining solutions( coffee, red wine, curry solution) or distilled water(control) for 28-day test period. Color of the specimens was measured with a spectrophotometer(Color Eye 7000A) using CIE $L^*a^*b^*$ color space relative to CIE standard illuminant D65 at baseline, 1day, 3days, 7days, 14days, 21days and 28days after staining. The color differences( ${\Delta}{E^*}_{ab}$) were calculated. The results were obtained as follows ; 1. The mean color changes(${\Delta}{E^*}_{ab}$) of the composites were greatest in curry solution, then red wine, coffee and distilled water, in decreasing order. 2. The mean color changes(${\Delta}{E^*}_{ab}$) of the composites were greatest in Z350, Z250, Tetric Ceram and P90, in decreasing order.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.64-71
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• 2005

In this study, we attempted to apply ultrasonic treatment for the preservative treatment of two softwood species, Korean pine and Japanese red pines to evaluate its effectiveness. Wood samples were submerged in oilborne preservative, copper naphthenate (NCU) and waterborne preservative, alkyl ammonium compound (AAC) and then treated with ultrasonic wave of 40 kHz, 400 W. After the treatment, the retention and penetration depth of these preservatives in the specimens were measured as a function of treatment time. Both the retention and penetration depth were continuously increased with increasing the treatment time up to 120 hours, where the retention reached about 95% by the application of AAC and the penetrating depth of 95% and 83% by the application of NCU, respectively for both species. The results of electronic microscopic observation showed that the improved retention capacity could be attributed to air deflation, wood extractive deflation working of ultrasonic wavelength, and destruction of wood pits which served as the pathway of preservatives. The results suggested that the use of ultrasonic treatment could be applied to thick wood veneers for the production of laminated wood products.

• Journal of the Korean Wood Science and Technology
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• v.32 no.2
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• pp.50-57
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• 2004

This study attempted to evaluate the water repellency and drying effectiveness of linseed oil treated-solid wood at high temperature by immersion. The moisture content of green wood (Pinus densiflora) sample (above 90%) was reduced about 10% after 6 hours treatment at 150℃. When the treated samples were cut into cross section along the length, it was observed that the linseed oil penetrated into up to 20% of the sample cross section area in all locations. However, a strength loss of the specimen was not detected. The pre-drilling before linseed oil treatment was effective in reducing the defects such as checks and splits, and improved the linseed oil penetration into all samples from the surfaces. The result of water absorption test of treated-wood showed that the water repellent efficacy of treated-wood was greater than that of the control. The anti-fungal activity of treated samples using five sap stains and thee decay fungi was not detected in broad-spectrum toxic mechanism. However, decay test using white rot fungi (Tyromyces palustris) and brown rot fungi (Trametes versicolor) showed that the treated sample has a decay resistance to these two fungi.