• Journal of Ginseng Research
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• 제22권3호
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• pp.211-215
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• 1998

A rapid separation of an edible panaxadiol (PD) and panaxatriol (PT) in ginseng saponins has been investigated by benzene ethylene resin adsorption method. Briefly, powdered red ginseng was extracted with water. The obtained ginseng extract were dissolved in suitable volume of distilled water, and adsorbed on the benzene ethylene resin with 200 folds water of the resin weight. Sugars and hydrophilic character compounds not absorbed were washed with water, and eliminated by 10-fold water of the resin weight. An edible panaxadiol and panaxatriol can be perfectly separated from ginseng saponins with the fractions below 40% aqueous ethanol and over 45% as an fluent.

• Journal of the Optical Society of Korea
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• 제12권3호
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• pp.166-169
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• 2008

The submersion monitoring system based on a reflective side-polished optical fiber submersion sensor with an optical fiber mirror was shown to be an effective alarm system with remote monitoringwhen the drainage capacity of a common utility duct is exceeded due to heavy rainfall. The proposed sensor was connected to an existing installed optical fiber network at a height of 250mm in a common utility duct, and then tested under sample materials(distilled water, river water, sea water, foul water, muddy water, petroleum, edible oil) at a distance of 1km from the sensor for remote sensing. In experiments, the proposed real-time sensor system reduced maintenance cost and improved monitoring efficiency by using a reflection-type side-polished optical fiber submersion sensor efficient for remote monitoring of a common utility duct.

• 한국응용과학기술학회지
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• 제34권4호
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• pp.778-786
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• 2017

In this study, analyzed the changes occurred after adding casein emulsions to water - dispersed polyurethane using polypropylene glycol (PPG). For this purpose, anionic water - dispersed polyurethane containing PPG, IPDI and DMPA and casein emulsion prepared by dissolving casein in distilled water using ammonia water were prepared. As a result of measuring the alkali resistance by using the prepared resin, there was no change in the physical properties. The tensile strength of the sample having a high casein content was measured to be $2.227kgf/mm^2$. Elongation was measured at 474% for samples containing less casein and The abrasion resistance was measured as 46.090 mg.loss of sample containing much casein as a result of the surface roughness measurement.

• 한국막학회:학술대회논문집
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• 한국막학회 1996년도 제5회 산학협동 심포지움 (먹는 물과 막분리공정)
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• pp.39-64
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• 1996

Probably over most of recorded time, the quality of drinking water has been praised for good health and blamed for bad health. Certainly it is true, considering pathogenic organism that cause typhoid fever, giardiasis, etc., or considering chemical contaminants suspected of causing cancer. Drinking "natural" waters with a high mineral content is generally accepted to be healthy. Water containing very low levels of total dissolved solids (TDS), such as distilled water, is believed by some to help "cure" arthritis by "washing out" calcium from deposits in joints. Along with this reasoning, many believe that drinking very tow TDS water, treated by distillation, reverse osmosis (RO) or deionization (DD, "leaches" minerals from the body and causes mineral deficiencies with subsequent ill health effects.cies with subsequent ill health effects.

• 한국환경보건학회지
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• 제22권1호
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• pp.1-4
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• 1996

I have conducted two testings to find out which water is better for drinking water. First, I made 20 mM L-DOPA solutions by solving L-DOPA (3,4-Dihydroxyphenylalanine) in tap water, Waters' mineral water and reverse osmotic water. Then I measured activities after adding Tyrosinase (purifide enzyme, step 3), which was extracted from Salanum melongena(mad apple), in each L-DOPA solution. Second, I solved 0.1, 0.5 and 0.9% salt in each 20 mM L-DOPA distilled water to measure activity of each salt solution. The results of the testings are as follows: 1. 10 minutes after adding Salanum melongena(mad apple) tyrosinase in each L-DOPA solution, activity of Waters' mineral water was 0.867 tap water 0.777 and reverse osmotic water 0.742. 2. Activity of Waters' mineral water was higher than that of tap water by 10.4% and higher then reverse osmotic by 14.4%. 3. Activity of Waters' mineral water was much higher than that of 0.9% salt water by 41.8%. 4. The optimum pH of Salanum melongena (mad apple) tyrosinase is 9.0. Most enzymes working in the human metabolism are alkaline and body fluids' pH also alkaline. In conclusion, an alkaline water is believed better than an acidic water for drinking.

• Journal of the Korean Wood Science and Technology
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• 제13권3호
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• pp.49-53
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• 1985

The effects of pre-treatments, the hot water extraction of wood meal and the addition of chemical ($CaCl_2$) to wood-cement water system on the properties of wood-cement composite such as modulus of rupture (MOR), modulus of elasticity (MOE), water sorption ratio and swelling ratio of resulting boards were studied in this experiment. The wood meals through 0.83mm(20 mesh) and retained on 0.42mm(35 mesh) screen were prepared from Pinus densiflora S. at Z. and Larix leptolepsis G. For hot water extraction, 500 grams of wood meal for each species were heated to boiling with 1,500ml of distilled water in 2-liter beaker for 6 hours. Every 2 hours, the wood meals were washed with boiling distil1ed water and reheated to boiling again. After 6 hours boiling, the boiled wood particles were collected by pouring this particles on 200 mesh screen. The collected particles then washed twice with hot distilled water and dried for 24 hours in an oven at $109{\pm}20^{\circ}C$. A mixture of 663.4 grams of cement with 331.7 grams of wood meal based on oven-dry weight were dry-mixed in a plastic vessel. The mixture was kneaded with 497.6ml of distilled water in the ratio of 1.5ml of water to a gram of wood meal. To add calcium chloride to the mixture as an accelerator, $CaCl_2$ 4% solution by weight per volume, was added to pine-or larch-cement board in the ratio of 3% to cement weight. To set wood-cement board, this mixture was clamped at 30cm ${\times}$ 30cm, in thickness of 1.5cm for 3 days at room temperature, declamped and then placed at open condition for 17 days. The target density was 1.0. The four specimens sized to 5cm in width and 28cm in length were used for MOR and MOE test for each treatment. After MOR test, the tested specimens were cut to the size of 5cm ${\times}$ 5cm for water sorption and swelling test. The twenty specimens used to measure the water sorption ratio (soaking 24 hours) and ten of these were used for swelling ratio measurement The results obtained were as follows: 1) Larch was not suitable for wood-cement boards because larch-cement board developed no strength, but pine showed 97.9kg/$cm^2$ by hot water extraction. 2) To increase MOR, hot water extraction was more effective than the addition of $CaCl_2$ in pine and larch because the $CaCl_2$ addition was seemed to speed up the ratio of cement hydration without reacting with the wood substances. 3) The water sorption ratio was lowered by the addition of $CaCl_2$ to wood-cement system because the chemical additive accelerated the rate of cement hydration. 4) In pine-cement board, the swelling ratio from 0.37 to 0.42 percent was observed in length and the swelling ratio from 0.88 to 2.0 percent in thickness. As a rule, the swelling ratio of wood-cement board was very low and the swelling ratio in thickness was higher than in length.

• 대한치과의사협회지
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• 제57권5호
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• pp.264-268
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• 2019

Objectives: This study aimed to measure the water sorption / solubility of Biodentine, composite resin and glass ionomer cement. Materials and Methods: The materials used in this study were Biodentine(BD), Filtek Z250(FZ) and Ketac Molar(KM). Twenty disc-shaped specimens of each material were prepared of 6mm diameter and 1mm thickness. All specimens were desiccated for 24 hours and weighed(m1). After then, They were immersed in distilled water and stored at $37^{\circ}C$. 1 week later, They were washed with running water, wiped with absorbent paper and weighed(m2). Finally, They were dried for 24 hours and weighed(m3). Water sorption and solubility, net water uptake were calculated. Results: KM and BD showed high water sorption than FZ(P<0.05). KM and BD exhibited similar water sorption(P<0.05). BD exhibited high solubility than KM(P=0.012). BD exhibited high net water uptake than FZ(P=0.008). Conclusion: Biodentine showed higher water sorption, solubility and net water uptake than Filtek Z250 and Ketac Molar. Within limitation of this study, it is not recommended to use Biodentine for permanent restoration.

• 대한치과교정학회지
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• 제30권4호
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• pp.475-481
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• 2000

본 연구는 침수 및 온도변화에 따른 레진 브라켓 wing의 파절양상을 비교하여 구강내 환경이 레진 브라켓 wing의 물성변화에 미치는 영향을 관찰해 보기 위하여 시행되었다. 본 연구의 재료로 레진 브라켓 75개와 금속 브라켓 25개를 사용하였는데, 레진 브라켓은 상온에서 5개월 동안 방치한 경우와 $37^{\circ}C$의 증류수에 6개월 동안 침수시킨 경우, 그리고 $37^{\circ}C$의 증류수에 6개월 동안 침수시킨 상태에서 1개월에 350회씩 총 2,100회의 열순환 시킨 경우의 3가지 군으로 구분하여 처리하였다. 만능물성 시험기를 이용하여 금속 브라켓의 경우 wing의 변형강도를, 레진 브라켓의 경우 파절강도를 각 군별로 측정하고 비교 분석하여 다음과 같은 결과를 얻었다. 1. 금속 브라켓 wing의 변형강도에 비하여 레진 브라켓 wing의 파절강도가 매우 낮게 나타났으며 통계적으로 유의한 차이가 있었다(p<0.001). 2. 상온에서 6개월 동안 방치한 군에 비하여 침수시키거나 침수 및 열순환 시킨 군에서 브라켓 wing의 파절강도가 낮게 나타났으며 통계적으로 유의한 차이를 보였다(p<0.001). 3. 단순침수에 비하여 침수 및 열순한 시킨 군의 브라켓 wing의 파절강도가 더 낮게 나타났으며 통계적으로 유의한 차이가 있었다(p<0.001). 이상의 결과는 구강내 환경에 의하여 레진 브라켓 wing의 물성이 약화되므로 이의 강도증가를 위한 적절한 대책이 필요함을 시사하였다.

• 생명과학회지
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• 제13권2호
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• pp.168-174
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• 2003

천연 미네랄 성분을 함유한 medilite 침출수를 이용한 녹차 추출물에 의한 화학적 성분조성과 항산화 활성을 증류수 침출 녹차 추출물과 비교하였다. 항산화 활성은 DPPH법 및 microsone 생체막 지질 과산화물 생성정도를 나타내는 TBARS법으로 측정하였다. 녹차 추출물의 총 폴리페놀성 화합물과 추출 수율은 medilite 325 mesh, 600 mesh, DW 추출물 순으로 나타났다. DPPH법에 의한 0.05%와 0.1%의 녹차 추출물에서 항산화 활성은 60.95% ∼ 64.15% 사이였다. 간 homogenate 및 microsone 생체막 지질 과산화물 생성 억제 정도는 medilite 325 mesh 및 600 mesh 침출 녹차 추출물에 비해 증류수 침출 녹차 추출물에서 현저히 억제되었다. 특히 Fe 함량은 증류수 침출 녹차 추출물에 비해 medilite 325 mesh 및 600 mesh 침출 녹차 추출물에 현저히 높았다 이러한 medilite 침출 녹차 추출물에서 높은 Fe성분 함량은 microsone 생체막 지질 과산화물의 생성 촉진과 관련된 것으로 사료된다. 이상의 결과에서 녹차 추출물 중의 총 폴리페놀성 화합물, 추출 수율 및 미네랄 성분은 증류수에 비해 medilite 침출수를 이용함으로써 대체적으로 증가하는 결과를 얻었다.

• 한국전기전자재료학회논문지
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• 제13권12호
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• pp.1063-1068
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• 2000

Water treeing in underground distribution power cable is not easy to observe by nondestructive method and it has very complex patterns. This study describes the principles and practices of a continuous observation of initiation and growth of tree in polymeric insulation material using an image measurement technique. Using this technique we could observe water tree and the growing process of electrical tree due to the water tree and the growing process of electrical tree due to the water tree. All of these growing process is analyzed quantitatively by image measurement program composed of borland c++. We fabricated the thin film type specimen to observe water tree easier and also the needle electrode was prepared by etching method using electrolytes. Initiation and the growth of three was observed somewhat different depending on the applied voltage and the water electrode. AgNO$_3$solution electrode accelerates the initiation and the growth of water tree, compared to those of distilled water electrode. The water and the electrical tree occurred by water tree has discontinuous growth characteristic.