• Korean Journal of Optics and Photonics
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• v.4 no.2
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• pp.220-225
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• 1993

This is the first reported observation of absorption and emission of glasses with a 4d transition metal ion(rhodium). The optical absorption and photoluminescence spectra, and the lifetimes of rhodium ions in phosphate glasses are interpreted on the basis of strong-field scheme of Sugano-Tanabe diagram. We conclude that rhodium ion is present in its divalent form. $^2 E{\rightarrow}^2 T_1$ and $^2 E{\rightarrow}^2 T_2$ transitions are superimposed and observed at 460 nm. Whereas $^2 T_1{\rightarrow}^2 E$ and $^2 T_1{\rightarrow}^2 E$ transitions are observed at 650 nm and 580 nm, respectively.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.12
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• pp.1007-1012
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• 2017

In this study, we performed the deployment test of shape memory polymer specimens for space antenna design. Poly(cyclootene) was cross-linked by dicumyl peroxide to make a PCO shape memory polymer. A miniature specimen with 120 mm diameter for a deployable antenna was fabricated with the PCO shape memory polymer. To investigate the deployment performance, the folded specimen as a temporary shape was heated by two heaters to the $15^{\circ}C$ higher temperature than the glass transition temperature of shape memory polymer. Firstly, the specimen was installed horizontally and tested. The deploying motion was captured by a digital camera and analyzed by a Tracker program. To reduce the effects of gravity, the specimen was installed vertically and tested again. The deployment performance of a shape memory polymer was investigated by comparing the results of horizontal and vertical installation tests.

• Journal of the Microelectronics and Packaging Society
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• v.13 no.3 s.40
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• pp.39-45
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• 2006

This study was investigated the thermal properties of underfill with various epoxy resins using thermal analysis methods such as differential scanning calorimetry (DSC), thermo gravimetry analysis (TGA), dynamic mechanical analysis (DMA) and thermo-mechanical analysis (TMA). And, the adhesion strength of the underfills/FR-4 substrate was evaluated. The glass transition temperature (Tg) of underfill which was composed the cycolaliphatic epoxy resin was lower than that of underfill which was not composed the cycolaliphatic epoxy resin. The thermal degradation of underfill was composed of two processes, which involved chemical reactions between the degrading polymer and oxygen from the air atmosphere. The coefficient of thermal expansion (CTE) of underfill which was composed the cycolaliphatic epoxy resin was higher than that of underfill which was not composed the cycolaliphatic epoxy resin. The excessive curing temperatures caused a weak boundary layer of epoxy resin, which resulted in a deterioration of mechanical properties in the epoxy resin and thus led to poor adhesion property between the underfill/FR-4 substrate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.131-135
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• 1992

For the investigation of the effects of mushrooms on prevention of hypercholesterolemia, dietary hyperc-holesterolemic rats were fed for 2 weeks with basal diet containing 5% G. lucidum, 5% L. edodes, 5% A. judae and 10% G. lucidum, 10% L. ededos or 10% A. judae mushroom. Concentrations of total cholesterol, HDL-cholesterol, LDL-cholesterol, triglyceride, phospholipid, free-cholesterol, cholesteryl ester, VLDL and chylomicron in serum were analyzed. The result obtained are as follows : Concentrations of total cholesterol, LDL, LDL-cholesterol in serum were lowest in the group 6 (10% L. edodes mushroom) and HDL-cholesterol concentration in serum was significantly higher than the concentrations of the control group. Concentrations of triglyceride, phospholipid, free-cholesterol, cholesteryl ester in serum were lower than the concentration of the control group, and the concentrations of triglyceride, cholesteryl ester in group 6 were lower than those of the other groups. Concentrations of phospholipid and free-cholesterol in group 3 were lower than those of the other groups.

• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.205-209
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• 2016

The influence of titania nanorods with an average diameter of 10 nm and an average length of 30 nm on the electrohydrodynamic instability of block copolymer (polystyrene-b-poly(2-vinylpyridine)) thin film was investigated in this article. The presence of titania nanorods increased the dielectric constant of the film, which resulted in a systematic reduction in the wavelength of the surface instability. Cross-sectional transmission electron microscopy analysis indicated that the migration/aggregation of titania nanorods did not occur as a result of the applied electric field. This work can provide a simple route to the pattern formation using electrohydrodynamic instability with an aid of nanoparticles.

• 비료회보
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• s.563
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• pp.11-16
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• 2004

전 세계적으로 입상 배합비료의 형태로 농작물 재배업자들에게 전달되는 비료의 비율은 지난 30년간 꾸준히 증가했다. 앞선 기술을 개발하고 있는 미국에서는 비료 생산 및 유통에 관한 경제학으로 인해 특히 입상 배합비료(BB)가 촉진되고 있으며, 현재 전국에 걸쳐 5,000 곳의 혼합설비가 산재해 있다. 혼합 기술의 주요 공급업체인 A.J. Sackett & Sons Co.의 프로젝트 엔지니어인 찰스 포어미사니도 설명한 것처럼, 혼합에는 농경법의 측면이나 경제적인 측면에서 여러 가지로 유리한 점이 있다.

• 대한두경부종양학회:학술대회논문집
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• 2006.11a
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• pp.220-220
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• 2006

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05a
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• pp.97-97
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• 1992

• Proceedings of the Korean Ceranic Society Conference
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• 2000.04a
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• pp.81.1-81.1
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• 2000

• 대한미세수술학회:학술대회논문집
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• 1996.10a
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• pp.174-174
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• 1996