• 한국주조공학회지
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• 제28권6호
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• pp.282-287
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• 2008

The effect of CaO mold on the formation of reaction layer was investigated. CaO mold was prepared by mixing of Colloidal silica($NALCO^{(R)}$ 1130) and an $ZrO_2$, CaO at room temperature. The dried at $20{\pm}3^{\circ}C$, 75% humidity for 12hrs. Sample was prepared from the Cp-Ti(grade-2) and melted by high frequence induction melting system in the vacuum condition. The react ion layer of Ti was confirmed by optical microscopy, microhardness(Hv) and X-ray diffraction. Thickness of reaction layer using the CaO stabilized ZrO2 was thinner than the CaO added ZrO2. And thickness of reaction layer were decreased with decreasing pH of slurry. CaO addition in the slurry could not controlled reaction between molten Ti and investment mold. On the other hand, the CaO chemical bonded ZrO2 by stabilization treatment could controlled reaction between molten Ti and investment mold.

• 동아시아식생활학회지
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• 제5권3호
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• pp.317-337
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• 1995

"Sinsulro(신선로)" is the famous soup of Cho-sun Dynasty Royal Cuisine, and the original food name is "Yulgujatang(열구자탕)". The first record is on [Sumunsasul] (1740) and the origin history related with Hirang-Jung is on [Headongjukji] and [Chosunyorihak]. From the analysis with Royal banquet menu and 16 kinds of old culinary literatures, "Sinsulro" are contained 54 and 70 material items and used variety cooking methods. Soup base of "Sinsulro" is well boiled meat, shank, brisket, stomach and intestine of beef with water, Some of beef is made meatball and seasoned raw meat. Beef marrow and tripes and liver are sauted with egg. Dried abalone and sea cucumber are soaked in water and then cutting slices after well boiled. Sliced white fish fillet are sauted with egg. Egg white and egg yolk made to thin sheet on pan with oil. Dropwort made to one sheet with flour and egg. Radish are boiled with meat soup and other vegetable are cooked with boiled or sauted. Seeds of pinenut, gingko, walnut are used of decorative seasonings. Filling mehtods of the Sinsulro casserole, the first layer is seasoning raw beef meat, 2nd layer is cooked slice of meat and radish, 3rd layer is rectangle pieces of egg sheet and sauted fish and intestines of beef. The top layer is decorated with meatball and naked nuts. After hot soup is poured until top of the materials, buning charcoal put into the center fire place and then served.o the center fire place and then served.

• Journal of the Korean Wood Science and Technology
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• 제14권1호
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• pp.45-54
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• 1986

A study was conducted to determine the physical properties related to drying characteristics, the seasonal air drying curves and the kiln drying schedule for taun lumber imported and utilized. This kiln drying schedule was found by oven drying and developed by pilot testing of green lumber and partially air dried lumber. The results of this study were as follows; 1. Average green specific gravity and standard deviation of heartwood lumber were 0.60${\pm}$0.03 and those of sapwood lumber were 0.64${\pm}$0.02. 2. Radial shrinkage from green to air dry and from green to oven dry were 3.05 percent and 5.96 percent respectively, and tangential shrinkage from green to air dry and to oven dry were 5.49 percent and 8.74 percent respectively. 3. Drying time for 25mm thick green lumber (50 percent moisture content) air dried to 30 percent moisture content were 14 days in springtime. 6 days in summertime, and 12 days in autumntime, whereas for 50mm thick lumber in 36 days in springtime, 18 days in summertime, 38 days in autumntime. 4. Kiln drying schedules developed by oven drying were T8-B3 for 25mm thick lumber and T5-B2 for 50mm thick lumber. 5. Kiln drying curves of green 25mm and 50mm thick lumber were similar to those of partially air dried lumber from the level of 30 percent average moisture content. Green 25mm thick lumber (55.7 percent moisture content) was dried to 9.3 percent moisture content in 101.5 hours and green 50mm thick lumber (65.6 percent moisture content) was dried to 11.5 percent moisture content in 526 hours. 6. End checking for green 25mm thick lumber occured in 49.6 percent moisture content and reached maximum amount in 27.6 percent moisture content and closed in 15.8 percent moisture content. 7. End checking for green 50mm thick lumber and partially air dried lumber developed and reached maximum amount earlier then for 25mm thick lumber. 8. Final moisture content of surface layer for 50mm thick lumber was one half of that of core, and moisture content equalized in the lumber after nine days of room conditioning. 9. Casehardening for 50mm thick lumber was slight and was conditioned after nine days of room stroage. 10. Drying defects, such as end checking and surface checking, were not observed and the quality of dry lumber was first.

• 대한기계학회논문집
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• 제17권8호
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• pp.2088-2098
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• 1993

A mathematical model of freeze drying by sublimation was suggested and used to estimate the drying time. Under the various conditions, the drying time of pure water and carrot was numerically calculated for the suggested model. Optimal policies of freeze drying were investigated experimentally in a laboratory freeze dryer. It was found that the shortest drying times could be obtained when the chamber pressure and condenser temperature were kept at their lowest values and the best method of heat transfer for sublimation was the conduction involving radiation. The sublimation drying period was finished when the bottom temperature of material could be reached at near $0^{\circ}C$ from frozen temperature.

• 한국세라믹학회지
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• 제31권11호
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• pp.1323-1329
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• 1994

Tape casting and lamination were used to produce heterogeneous laminates with alternating layers of different porosity and homogeneous laminates with component layers of the same porosity. The pore structure was investigated for heterogeneous laminates, and bend strength was measured for comparison with that of homogeneous laminates. For a reference, strength measurement was made for the porous body fabricated by sintering samples dry-pressed at low pressure with spray-dried granules. Strength increase, in the range 50~120 MPa, was achieved in the presence of the surface dense layer, while extensive delamination, presumably responsible for enhanced fracture toughness, took place through the internal porous layer.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.17-24
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• 1998

Plasma-sprayed coatings were obtained by spray-dried $Cr_2O_3$ powder with and without Mo addition. A reciprocal type tribo-tester was employed to examine friction and wear behavior of the specimens at room temperature. The composition and the worn surface of coated specimens were observed by XRD and SEM. The results showed that friction Coefficient of the Mo added specimens were lower than one of $Cr_2O_3$ specimen. But $Cr_2O_3$ specimen had a lower wear loss. Protecting layer were observed at the worn surface of coated specimens with Mo addition.

• 한국해양공학회지
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• 제19권3호
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• pp.47-53
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• 2005

Model for dust and salt transportation from the dried bottom of the Aral Sea is suggested. Theoretical analysis is based on the turbulent diffusion equation for the averaged function of passive impurity concentration. One-layer model of the atmospheric boundary layer is assumed. Impurity precipitation rates are calculated as the functions of the particle size and the distance source of particles. Analytical solutions for the point and two-dimensional sources of impurities are found. Model calculations for salt and sand transport from the Aral Sea basin are made on the basis of 2D source model with a constant intensity.

• 생약학회지
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• 제2호2호
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• pp.89-93
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• 1971

This study is about the five species of the genus Thalictrum growing abundantly in South Korea. Dried roots of plants; T. aquilegifolium var. japonica, T. simplex var. affine, T. actaefolium, T. tuberiferum were compared by morphological observation and screening test on the ingredient extracted by methanol, ether etc.. The experiments by thin-layer chromatography was at tempted to find out the similarity and the difference among them. In conclusion, the author found that: 1) A special component similar to coumarin was found under UV-ray from T. actaefolium. 2) By thin-layer chromatography, they show the corresponding spot supposed to be that of berberine and magnoflorine according to the $T_{ABLE}\;IV$. Therefore it is worthwhile considering that Thalictrum species would be a substitution for Epimedium species used as a tonic. 3) Thalictrum species has resemblance of ingredient and chemotaxonomy gives more help to classify them than the morphology.

• Journal of the Korean Wood Science and Technology
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• 제36권6호
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• pp.96-104
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• 2008

본 연구에서는 고대 칠 기법을 규명하기 위하여 4가지 그룹의 표준칠편을 제작하여 광학현미경(투광, 낙사광, 편광)을 이용한 관찰을 실시하였다. 그룹 I 은 투명한 적갈색을 띠며 일부 층의 구분이 불명확하였고 연마가 된 층은 구분이 쉽게 되었다. 그룹 II는 대부분 투명 황갈색을 띠며 목재표면에 먼저 흑색안료를 메운 후 칠한 칠층과 흑색안료를 혼합하여 칠 한 칠층은 구분이 가능하였다. 그룹 III은 칠이 경화되는 과정에서 상층 부분이 먼저 막을 형성하고 내부는 칠과 불포화지방산이 산화 건조되어 상층의 칠층이 분리되어 관찰되었다. 그룹 IV의 칠도 막은 편광에서 관찰시 철 성분이 검은색과 붉은색으로 혼합되어 보이며 토분은 실리카 결정이 빛의 반사에 의하여 구분되어 졌다. 또한 석간주 칠층은 붉은색을 띠고 주칠과 석간주가 혼합된 칠은 윗부분과 아랫부분이 짙은 붉은 색을 띠며 가운데는 밝은 붉은색으로 구분되어 졌다.

• 한국초전도ㆍ저온공학회논문지
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• 제11권1호
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• pp.1-4
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• 2009

Mechanical and electrical properties of silver stabilizer layer of coated conductor, which as prepared with nano silver paste as starting materials, have been investigated, Nano silver paste was coated on a YBCO film by dip coating process at a diping speed of 20m/min. Coated film was dried in air and heat treated at $400{\sim}700^{\circ}C$ in an oxygen atmosphere. Adhesion strength between YBCO and silver layer was measured by a tape est(ASTM D 3359). Hardness and electrical conductivity of the samples were measured by pencil hardness test (ASTM D 3363) and volume resistance test by LORESTA-GP (MITSHUBISHD, respectively. The sample heat-treated at $500^{\circ}C$ showed poor adhesion 1B, but samples heat treated at higher than $600^{\circ}C$ showed enhanced adhesion of 5B. The silver layer heat-treated at $700^{\circ}C$ showed the high hardness value larger than 9 H, low volume resistance, surface resistance value as well as superior current carrying capacity compared to sputtered silver. SEM observations showed that a dense silver layer was formed with a thickness of about $2{\mu}m$. Dip coated silver layer prepared by using nano silver paste showed superior electrical and mechanical characteristics.