• 한국세라믹학회지
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• 제47권6호
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• pp.553-559
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• 2010

The synthesis behavior of nanoporous silica aerogel in the macroporous ceramic structure was observed using TEOS as a source material and glycerol as a DCCA(dry control chemical additive). Silica aerogel in the macroporous ceramic structure were synthesized through a sono-gel process. The wet gel in the macroporous ceramic structure were aged in ethanol for 72 h at $50^{\circ}C$. The aged wet gel was dried under supercritical drying condition. The addition of glycerol has a role of giving the uniform pore size distribution. The reproducibility of aerogel in the macroporous ceramic was improved in the glycerol(0.05 mol%) added to the silica sol and TEOS : $H_2O$=1 : 12.

• International Journal of Concrete Structures and Materials
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• 제2권2호
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• pp.161-167
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• 2008

Optimization of concrete mixing system is very important for the production of quality mixture of concrete and requires very complicated, specialized knowledge as there are a variety of variables that influence the result. One of the methods of optimizing the concrete mixing system is to minimize the volume of cement paste which, in turn, means maximizing the volume of aggregate. The purpose of this study is to determine the minimum volume of cement paste used in the design of concrete mixture and to design the optimum concrete mixing system based on the fluidity of mortar and concrete. In determining the minimum volume of cement paste, experiments of mortar and concrete were performed based on their workability, material segregation and bleeding. Type of aggregate, granularity distribution and sand percentage were used as test parameters and measurements were taken of the distribution of granularity, usage of HRWRA, minimum volume of paste and drying shrinkage and compressive strength of concrete.

• 한국식품영양학회지
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• 제31권5호
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• pp.647-652
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• 2018

Extracts from bay leaves, Chongbaek (Allium fistulosum L.), Hutgae (Hovenia dulcis Thunb.) fruit, and green tea, using Soju (Korean alcohol, $30^{\circ}$) as a solvent were analyzed for their antioxidative properties. The eels were evenly coated with the extract concentration equivalent to 2% of their total weight and dried for 15 hours at $35^{\circ}C$ using an air blower. The DPPH radical scavenging effect, acid value and peroxide value of semi-dried eel, and linoleic acid peroxidation of eel oil were investigated. The highest level of DPPH radical scavenging was found in green tea extracts, followed by Hutgae fruit extract and bay leaves extract (p<0.05). The acid value and peroxide value of Hutgae fruit extracts coated eels refrigerated for 21 days were the lowest followed by the green tea extract coated eels. During the 20 days reaction period, all four kinds of extracts analyzed were found to effectively decrease linoleic acid peroxidation. Among them, Hutgae fruit and green tea extracts decreased the peroxide content of eel oil steadily and for a longer period when compared to other extracts. In conclusion, pre-application of Hutgae fruit and green tea extracts on eels before drying was found to be effective in delaying peroxidation in eels during the drying process and refrigeration.

• 한국분말재료학회지
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• 제18권3호
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• pp.269-276
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• 2011

The synthesis behavior of nanoporous silica aerogel in the macroporous ceramic structure was observed using TEOS as a source material and glycerol as a dry control chemical additive (DCCA). Silica aerogel in the macroporous ceramic structure was synthesized via sono-gel process using hexamethyldiazane (HMDS) as a modification agent and n-hexane as a main solvent. The wet gel with a modified surface was dried at $105^{\circ}C$ under ambient pressure. The addition of glycerol appears to give the wet gel a more homogeneous microstructure. However, glycerol also retarded the rate of surface modification and solvent exchange. Silica aerogel completely filled the macroporous ceramic structure without defect in the condition of surface modification (20% HMDS/nhexane at 36hr).

• 한국포장학회:학술대회논문집
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• 한국포장학회 2006년도 정기총회 및 추계학술발표대회
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• pp.127-132
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• 2006

건강기능성 식품으로 각광을 받고 있는 키위과일의 건조 중 유효성분의 손실을 최대한 줄일 수 있는 진공동결건조법을 이용하여 키위과일을 동결건조하고 생키위, 동결건조키위 및 해동공정을 거친 해동키위를 시료로 하여 텍스츄어와 수분함량의 변화를 조사연구 하였다. Freeze Drying Kiwi는 생Kiwi보다 수분함량이 크게 감소되어 텍스츄어(hardness, firmness, stiffness) 수치가 전체적으로 매우 높게 나타났으나, 해동(Re-Hydration Kiwi)시킨 경우에는 텍스츄어가 생키위의 $1.2{\sim}l.3$배 정도로 나타나 동결건조법으로 건조하면 키위의 복원성이 매우 좋은 것으로 나타났다. 키위는 동결건조에 의해 수분함량이 크게 줄어 식품의 부패요소 중 중요요소인 수분활성도(Aw; Water Activity)가 크게 낮아져 식품의 원형이 비교적 그대로 유지되면서 유통기한(Shelf life)이 크게 연장되는 것을 알 수 있었다.

• 한국수산과학회지
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• 제8권4호
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• pp.213-216
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• 1975

항산화제 및 약제처리가 옥돔 건제품의 품질에 미치는 영향을 실험한 결과 Tenox-II가 가장 산패방지 효과가 좋았고, 다음이 BHA, sustane, NDGA였으며, EDTA, 솔빈산 칼리움, CTC, $\alpha-naphylamine$은 효과가 없었다. 옥돔은 $0.1\%$ Tenox-II용액에 침지처리하여 건조한 다음 PVC 필름에 포장하여 저장하면 4개월간 품질을 안정하게 유지할 수 있었다.

• 한국조리학회지
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• 제12권4호
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• pp.269-283
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• 2006

To show the recognition of hand-sanitizer, we studied the answers of research questions where we got from the northern part of Seoul and Kyunggi Province. We had categorized two groups both industry-related people who work in restaurants, hygiene service shops, whole sales, government organizations, PC shops, factory-department stores and non industry-related people who work in schools, general offices for this study. 1. Hand sanitation level: Over 60% people washed hands 6 times a day. The group using water and soap was much bigger than the group using water for washing hands. For drying, people preferred wipe tissue, towels, clothes, non drying in that order. 2. Recognition of hand sanitizer and its usage experience: Most people(66.5%) did not know what hand sanitizer is, but they have positive attitude if they use this machine. 3. Place of hand sanitizer: The proper places to install were such public places as hospitals, restrooms, and restaurants. The fifties-group was the most frequently hand washing generation with over 9 times a day. 4. Comparison of recognition for hand-sanitizer by male and female: There were different results in each evaluation item by either male or female. The frequency and method of hand washing showed high in males, while females observed hand sanitization, installation requirements, installation areas, home installation, etc more than anything else.

• 한국식생활문화학회지
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• 제17권4호
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• pp.465-472
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• 2002

The effect of cooking(boiling, steaming and baking) and drying on the cholesterol content and formation of oxidized cholesterols and acid value in squid(Japanese flying squid, Todarodes pacificus) was studied. Cholesterol content of live squid meat varied with the portion sampled. The data from spectophotometric assay ranged from 263.2 mg/100g(mantle) to 315.8 mg/100g(tentacle). The cholesterol levels found for squid samples analyzed by gas chromatography(GC) were lower by 7% of total cholesterol for live squid meat and 24% for processed meat than those results by spectrophotometric assay. Cooking resulted some decrease in the initial total cholesterol content of raw meat from 10%(boiling for 5 min.) to 25%(steaming for 5 min.). The amounts of cholesterol remaining after baking were 68% for microwave oven samples and 64% for convection oven samples. Drying of raw tissue caused the greater reduction in cholesterol content than cooking but brought about no significant difference in samples stored for 6 weeks at $4^{\circ}C\;and\;20^{\circ}C$. Raw squid meats contained essentially no oxidized cholesterols, while the 22-hydroxychoesterol was detected in frozen meats. The additional oxidized cholesterols as cholestane-triol was indentified with 22-hydroxycholesterol in cooked samples. Sun dried meat stored at $4^{\circ}C\;and\;20^{\circ}C$ for 6 weeks had the three kinds of oxidized cholesterols such as 22-hydroxycholesterol, cholesta-3,5-dien-7-one and cholestane-triol. For the boiled and steamed squids, 10% higher acid value and 5% higher acid value respectively were observed but oven cooked samples resulted in a 50% higher acid value than raw samples. Squids had a 45% higher acid value than raw one during sundrying and presrevation at $20^{\circ}C$ but there was not a severe difference of acid value between $4^{\circ}C\;and\;20^{\circ}C$ stored samples.

• 한국디지털건축인테리어학회논문집
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• 제12권1호
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• pp.45-51
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• 2012

To see sunlight condition around in storage room, this study analyzers the scope both of sunlight and of the shade of sun into upper and lower window according to seasons. For this, this study investigates sun's seasonal changes, its effect of sunlight and notes antinomic conditions for ventilation and draft performance. In this, Architects of Jangkyunggak tride to block discoloration and fading due to ultraviolet rays and visible rays and block deterioration drying of the surface of Kyung-Pan due to infrared rays by oppressing sunlight flowing by means of narrowing the area of the upper window at front face that has a direct influence of Pan-Ga to avoid the exposure to direct sunlight.

• 한국식품영양과학회지
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• 제39권12호
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• pp.1826-1831
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• 2010

본 연구는 폐자원인 포도가공부산물을 활용한 기능성 소재 개발의 기초 자료 마련을 위해, 열풍 및 동결건조한 뒤 1~20 kGy의 감마선 조사를 실시한 포도가공 부산물의 품질 특성 및 항산화활성의 변화를 관찰하였다. 색도는 열풍건조 시료의 경우 3 kGy에서 가장 높은 L값과 a값을 나타낸 후 조사선량 증가에 따른 감소를 나타내었고, 동결건조시료의 경우 가장 높은 조사선량인 20 kGy에서 가장 높은 L값과 b값을 나타내어 열풍건조라는 고온의 전처리를 통한 색소의 파괴가 미리 진행되어 감마선 조사에 따른 영향을 나타내지 않았으며, 3 kGy의 감마선 조사는 열풍건조한 포도가공 부산물 시료의 색택에 좋은 영향을 미치는 것으로 나타났다. 총 페놀화합물의 함량을 측정한 결과, 열풍건조시료 메탄올 추출물에서는 3 kGy 조사구에서 가장 높은 함량을 나타내었고 조사선량 증가에 따른 감소를 나타내었으나, 비조사구보다는 조사구에서 더 높은 페놀화합물 함량을 나타냈다. 동결 건조시료 메탄올추출물의 경우, 비조사구에서 가장 높은 함량을 나타내었으나 조사구에서는 3 kGy 조사구가 가장 높은 페놀화합물 함량을 나타내었다. DPPH 및 ABTS를 이용한 라디칼 소거능의 측정 결과 역시 페놀화합물 함량의 측정 결과와 마찬가지로 열풍건조시료의 메탄올추출물에서 3kGy 조사구가 가장 높은 라디칼 소거능을 나타내었다. 환원력은 시료를 1~5 mg/mL의 농도로 희석하여 실험하였으며, 그 결과 열풍과 동결건조시료 모두 3 kGy 조사구에서 가장 높은 활성을 나타내었다. 따라서 본 연구를 통해 3 kGy의 감마선 조사는 포도 가공 부산물의 색택 및 항산화능을 향상시킴을 알 수 있었다. 하지만 가공부산물 활용의 측면에서 볼 때, 감마선 조사에 따른 포도부산물의 항산화 활성 증가는 미약하거나 없는 것으로 나타나 큰 의미를 갖지 못했다.