• Proceedings of the International Microelectronics And Packaging Society Conference
• /
• 2003.11a
• /
• pp.88-93
• /
• 2003

무전해 Ni-P와 Sn의 반응 및 Ni-P의 결정화에 대한 P 함량의 영향을 세 가지 다른 조성의 Ni-P (P 4.6, 9, 13 $wt.\%$)를 이용하여 연구하였다. $300^{\circ}C$까지 열처리한 모든 시편에서 $Ni_3Sn_4$ intermetallic compound (IMC)가 생성되었고 이들 시편을 $450^{\circ}C$까지 열처리한 경우 Sn 두께가 $0.5{\mu}m$로 작을 때 $Ni_3Sn_4$가 모두 $Ni_3Sn_2$로 변화하였다. nanocrystal인 Ni-4.6P는 Ni (111) texture를 유지하며 결정화되었고 Sn과의 반응시 형성되는 $Ni_3Sn_4$ IMC 또한 비정질인 Ni-9P, Ni-13P 경우보다 강한 (111) texture를 가짐이 확인되었다. Ni-P 막의 P 함량이 작은 경우 $Ni_3Sn_4$ IMC는 두껍고 조밀하게 형성되는 반면 P-rich layer 두께는 작아졌다.

• Journal of the Korean Ceramic Society
• /
• v.45 no.12
• /
• pp.782-787
• /
• 2008

Ni-ceria cermets have been extensively investigated as candidates for the anode in intermediate-temperature solid oxide fuel cells. We have used the citric method to synthesize nanocomposite powders consisting of NiO (Ni metal content: $40{\sim}60%$ by volume) highly dispersed in $Ce_{0.9}Gd_{0.1}O_{1.95}$ (CGO). The microstructure characteristics and sintering behaviors of the nanocomposites were investigated. No impurity phases were observed and the shrinkage of these substrates matched well with that of a CGO electrolyte with a specific surface area of $11\;m^2/g$. Densification of the CGO electrolyte layer to $<5\;{\mu}m$ thickness was achieved by co-firing the laminated electrolyte with the porous NiO-CGO substrate at $1400^{\circ}C$ for 6 h.

• Journal of Environmental Health Sciences
• /
• v.28 no.2
• /
• pp.71-80
• /
• 2002

To evaluate the skin toxicity of topical cyclohexane application (25mg/$\textrm{cm}^2$) was sequentially applied to the rat skin for four days. On the histopathological findings in the light micrographs, neutrophils and engulfed neutrophils are seen, and many cytoplasmic processes were appeared in proliferated layer whereas in the dermis area, increased numbers of fibroblast, accumulation of neutrophil and lipid droplets are demonstrated. On the other hand, applying the cyclohexane to the rat skin led to the remarkable rise of cutaneous xanthine oxidase activity and similar activities of superoxide dismutase and glutathione peroxidase and glutathione content and declined activity of glutathione S-transferase compared with control group. Especially the remarkably decreased activity of aniline hydroxylase (AH) was appeared in skin as little as scarcely determined. Furthermore, the applying the cyclohexane to skin led to the significantly increased activity of hepatic AH and alcohol dehydrogenase. These results indicate that oxygen free radical and intermediate metabolite of cyclohexane may be responsible for structural changes in skin by cyclohexane application to rat skin.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.5
• /
• pp.788-793
• /
• 1997

Addition of sugar, enzymatic hydrolysis and salt concentration were evaluated for their effects on the changes in some characteristics of Kimchi juice during fermentation. The Kimchi juice was prepared by brining and grinding of outer layer leaves of chinese cabbage, one of the wastes products of Kimchi processing, followed by fermentation proceeded significantly faster. Addition of sucrose or glucose at the ange of 0.5~2.0 % also improved the fermentation but the concentration effect was little. Enzymatic hydrolysis on the brined cabbage prior to fermentation with a commercial polysaccharides hydrolases also increased the fermentation. However the solid concentration in Kimchi juice was rather decreased by higher concentration of NaCl and enzymatic hydrolysis. The reducing sugar content showed a rapid decrease from 24 hours of fermentation and the effect of enzymatic hydrolysis was little.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.26 no.5
• /
• pp.794-799
• /
• 1997

The effective fermentation methods of Kimchi juice for utilization of outer layer of Chinese cabbage, an waste of Kimchi industry were studied. The Kimchi juice prepared with brining and grinding the waste of Chinese cabbage and addition of spices was fermented at $25^{\circ}C$. Addition of 5$^{\circ}C$15% fermented Kimchi juice of pH 5.4 at initial stage and pH 4.4 at middle state resulted in a significant increase in fermentation rate and solid content after 12 hours of fermentation. The combined method of enzymatic hydrolysis(0.1% viscozyme) of the brined and ground cabbage and addition of 2.0% NaCl, 1.0% sucrose and 10% fermented juice of pH 5.4 first and 4.4 during fermentation, respectively resulted in more rapid fermentation. The solid concentration was 5 times higher than control at maximum point and acidic and total flavor intensity were also significantly high.

• Land and Housing Review
• /
• v.9 no.2
• /
• pp.51-57
• /
• 2018

The causes of landslides are dependant on rainfall events and the soil characteristics of a slope. For the conventional slope stability, the slope stability analysis has been carried out assuming the saturated soil theory. But, in order to clearly explain a proper soil slope condition by rainfall, the research should be performed using the unsaturated soil mechanism suitable for a soil slope in the field. In the study, by using two major categories of soils in Korea, such as granite and gneiss weathered soils, landslide model test and finite element method have been compared with the difference of seepage and soil stability analysis. The hydraulic conductivity of gneiss weathered soil is slower than that of granite weathered soil, and the gneiss weathered soil contains much finer soils than the granite weathered soil. It was confirmed that the instability of the slope was progressing slowly due to the slow rate of volumetric water content of the surface layer.

• Journal of Surface Science and Engineering
• /
• v.29 no.6
• /
• pp.720-723
• /
• 1996

The behavior of electrodeposition of amorphous nickel-phosphorus has been studied from the point of deposition mechanism, kinetic parameters, morphology and formation of alloy films. The electorode reaction and electrode kinetics of deposition of nickel were significantly influenced by the content of phosphorus. The cathodic deposition of nickel-phosphorus alloy might be governed by the diffusion process of phosphorous acid. The direction of growth layer of the nickel-phosphorus alloy was different with substrate material. The formation of nickel-phosphorus alloy films was affected considerably by the solution compositions, electrolytic conditions and properties of the material as an underlayer.

• Proceedings of the Korea Society of Poultry Science Conference
• /
• 2001.11a
• /
• pp.64-65
• /
• 2001

Seven hundred twenty 56 wks old ISA brown layers were assigned to five dietary treatments for 12 weeks. Each treatment was consisted of 6 replications with 24 birds. Control diet was formulated to have 15% CP, 2800kcal/kg ME, 3.8% Ca and Cu-methionine chelate(Cu-Met) were added to control diet at the level of 25, 50, 75, 100ppm in Cu. Supplementation of 25, 75, 100ppm Cu in from of Cu-Met s increased egg productions by 2.11, 3.84, 3.66%, compare with control. Egg weight also increased by supplementation of Cu at 50, 75, 100ppm in Cu-Met. Gizzard erosion tened to increase by supplementary Cu-Met but were not significantly different. Supplementation of Cu at the level of 75, 100ppm Cu-Met treatments decreased crude fat level in liver. It concludes that supplementation of Cu at level in the form of 75 or 100ppm methionine chelate improves egg production with heavier egg weight and decreases crude fat content in the liver.

• Proceedings of the KWS Conference
• /
• 2009.11a
• /
• pp.205-209
• /
• 2009

Wetting properties between silver-copper-titanium braze alloys with different titanium contents up to 2.8 mass% and hexagonal boron nitride ceramics were investigated using sessile drop method at 1123K in Argon. The final contact angle is less than $30^{\circ}$ when the Ti content was over 0.41 mass%. Meanwhile, the contact angle curves show different behavior. In case of using braze alloy containing 2.8 mass% of titanium, the initial contact angle is acute angle just after the melting of braze. In case of brazes containing titanium less than 2.26 mass%, the contact angle is larger than $90^{\circ}$ at the beginning and slowly decreases to acute angle. The reaction layer of titanium nitride is observed at the interface. In addition, the reaction of Ti in the braze and N in the bulk h-BN seemed to show diffusion limited spreading.

• Journal of Pharmaceutical Investigation
• /
• v.17 no.1
• /
• pp.22-30
• /
• 1987

Evaluation method of crude drug preparations was studied in Saengmaek-san. Zig-zag TLC scanning profiles and high performance liquid chromatograms were obtained from Saengmaek-san and its each crude drug. A method using TLC densitometry and high performance liquid chromatography was established for the precise determination of ginsenoside $Rb_1$ in Saengmaek-san containing Ginseng Radix. Consequently, ginsenosicle $Rb_1$ content was 0.45-0.48 mg per g of Saengmaek-san. This method was found to be useful for the quality evaluation of oriental medicinal preparations.