• Biomedical Science Letters
• /
• v.24 no.4
• /
• pp.329-333
• /
• 2018

The purpose of this study is to investigate the anti-inflammation effect of the mixture, consisting of a series of different ratio of Ecklonia cava extract and scoria. Also, to make more functional scoria powder into cosmetic material, studies on the toxicity by cell viability assay. Scoria is found in large amounts in Jeju Island, as an adsorbent of heavy metal ions ($Ni_2{^+}$, $Zn_2{^+}$, and $Cr_3{^+}$) in an aspect of its efficient utilization. Marine plants such as Ecklonia cava contain high amounts of polyphenolic antioxidants. The purpose of this study was to examine the anti-oxidative and anti-inflammation effects of combination of mixture of Eckloina cava extrat and scoria with optimal ratio. Therefore, this study suggested that combination of mixture of Eckloina cava extrat and scoria and its attenuated the oxidative and inflammatory reactions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.11a
• /
• pp.99-102
• /
• 2002

The BSCCO superconductor materials of using Self-propagating High-temperature Synthesis (SHS) were studied. Mechano-chemical activation - as a pre-treatment of the reactants mixture - strongly influences the kinetic parameters, the reaction mechanism, and the composition and structure of the final product. In this paper as an effort for fabricating the SHSed BSCCO superconductor powder SHS method was considered to application in the synthesis of superconducting materials.

• Korean journal of food and cookery science
• /
• v.27 no.6
• /
• pp.653-659
• /
• 2011

The aim of this study was to determine the optimum amount of apricot seed powder to add to rice flour in oder to prepare Sulgidduk (traditional rice cakes). As the apricot seed powder level of the Sulgidduk increased, the moisture contents of the samples decreased (40.30~43.46%), and the color of L- and a-values also decreased, while the b-value increased. According to instrumental test results, hardness, springiness, gumminess, chewiness and adhesiveness were all highest in the 0% apricot seed powder sample. The cohesiveness of samples did not show a conclusive relationship with the level of apricot seed powder present. In sensory evaluation results, the 3% and 6% samples received high overall acceptability scores. In conclusion, based on both sensory and instrumental testing, the optimal Sulgidduk mixture consisted of 3~6% apricot seed powder added to rice flour.

• Korean journal of food and cookery science
• /
• v.26 no.5
• /
• pp.617-626
• /
• 2010

The purpose of this study was to determine the optimal mixing conditions of three different amounts of seatangle powder, sugar, and butter in germinated brown rice cookie prepared with seatangle powder. The experiment was designed according to the Central Composite Design of response surface, which showed 16 experimental points including 2 replicates for seatangle powder, sugar and butter. The mechanical and sensory properties of each test were measured, and these values were applied to the mathematical models. A canonical form and perturbation plot showed the influence of each ingredient on the final product mixture. The L value, a value and b value decreased with increasing seatangle powder content and increased with sugar content. The a value and b value increased with increasing butter content, whereas the L value decreased with increasing butter content. Hardness decreased with increasing butter content. The results of sensory evaluation showed very significant values for texture (p<0.001), taste (p<0.01), and overall quality (p<0.05). As a result, the optimum formulation by numerical and graphical methods was calculated to be seatangle powder 4.25 g, sugar 49.86 g, and butter 58.23 g.

• Korean Journal of Materials Research
• /
• v.21 no.2
• /
• pp.106-110
• /
• 2011

A high thermal conductive AlN composite coating is attractive in thermal management applications. In this study, AlN-YAG composite coatings were manufactured by atmospheric plasma spraying from two different powders: spray-dried and plasma-treated. The mixture of both AlN and YAG was first mechanically alloyed and then spray-dried to obtain an agglomerated powder. The spray-dried powder was primarily spherical in shape and composed of an agglomerate of primary particles. The decomposition of AlN was pronounced at elevated temperatures due to the porous nature of the spray-dried powder, and was completely eliminated in nitrogen environment. A highly spherical, dense AlN-YAG composite powder was synthesized by plasma alloying and spheroidization (PAS) in an inert gas environment. The AlN-YAG coatings consisted of irregular-shaped, crystalline AlN particles embedded in amorphous YAG phase, indicating solid deposition of AlN and liquid deposition of YAG. The PAS-processed powder produced a lower-porosity and higher-hardness AlN-YAG coating due to a greater degree of melting in the plasma jet, compared to that of the spray-dried powder. The amorphization of the YAG matrix was evidence of melting degree of feedstock powder in flight because a fully molten YAG droplet formed an amorphous phase during splat quenching.

• Journal of Powder Materials
• /
• v.10 no.2
• /
• pp.97-102
• /
• 2003

The powder-in sheath rolling was applied to the fabrication of $Al/Al_2O_3$ composite. A stainless steel tube with outer diameter of 12 mm and wall thickness of 1 mm was used as a sheath. Mixture of aluminum powder and $Al/Al_2O_3$ particles of which volume content was varied from 5 to 20 vol.% was filled in the tube by tap filling and then rolled to 75% reduction at ambient temperature. The re]]ed specimen was sintered at 56$0^{\circ}C$ for 0.5 hr. The $Al/Al_2O_3$ composite fabricated by the sheath rolling and subsequent sintering showed the relative density higher than 0.96. The tensile strength of the composite increased with the volume content of $Al_2O_3$ particles, and it reached a maximum of 90 MPa which is 1.5 times higher than unreinforced material. The elongation decreased with the volume content of $Al_2O_3$ particles. It is concluded that the powder-in sheath rolling is an effective method for fabrication of $Al/Al_2O_3$ composite.

• Journal of Powder Materials
• /
• v.21 no.1
• /
• pp.50-54
• /
• 2014

A powder-in-sheath rolling method was applied to a fabrication of a carbon nano tube (CNT) reinforced aluminum composite. A STS304 tube with an outer diameter of 34 mm and a wall thickness of 2 mm was used as a sheath material. A mixture of pure aluminum powders and CNTs with the volume contents of 1, 3, 5 vol was filled in the tube by tap filling and then processed to 73.5% height reduction by a rolling mill. The relative density of the CNT/Al composite fabricated by the powder-in-sheath rolling decreased slightly with increasing of CNTs content, but exhibited high value more than 98. The grain size of the aluminum matrix was largely decreased with addition of CNTs; it decreased from $24{\mu}m$ to $0.9{\mu}m$ by the addition of only 1 volCNT. The average hardness of the composites increased by approximately 3 times with the addition of CNTs, comparing to that of unreinforced pure aluminum. It is concluded that the powder-in-sheath rolling method is an effective process for fabrication of CNT reinforced Al matrix composites.

• Journal of Powder Materials
• /
• v.8 no.2
• /
• pp.98-103
• /
• 2001

Metallic tin powder with diameter less than 50 nm was synthesized by inert gas condensation method and subsequently oxidized to tin oxide ($SnO_2$) along the two heat-treatment routes. The $SnO_2$ powder of single phase with a tetragonal structure was obtained by the heat-treatment route with intermediate annealing step-wise oxidation, whereas the $SnO_2$ powder with mixture of orthorhombic and tetragonal phases was obtained by the heat-treatment route without intermediate annealing (direct oxidation). $SnO_2$ gas sensors fabricated from the nano-phase $SnO_2$ powders were investigated by structural observations as well as measurement of electrical resistance. The $SnO_2$ gas sensors fabricated from the mixed-phase powder exhibited much lower sensitivity against $H_2$ gas than those fabricated from the powder of tetragonal phase. Reduced sensitivity of gas sensors with the new orthorhombic phase was attributed to detrimental effects of phase boundaries between orthorhombic and tetragonal phases and many twin boundaries on the charge mobility.

• Journal of the Korean Ceramic Society
• /
• v.47 no.2
• /
• pp.183-188
• /
• 2010

$Ce_{0.8}Gd_{0.2}O_{1.9}$(GDC20) powder was synthesized by milling of $CeO_2$ slurry and Gd oxalate precipitation. The mixture of $CeO_2$ powder and Gd precipitates calcined at $600^{\circ}C$ for 2 h showed the particle size distribution similar to that of $CeO_2$ powder, which had been milled during the synthesis process. Attrition milling of the calcined powder with an average particle size of $0.36\;{\mu}m$ for 2 h resulted in a decrease in the particle size to $0.24\;{\mu}m$. Although the milled powder consisted of small particles(<$1\;{\mu}m$), a small amount of fine platy $Gd_2O_3$ particles, which had been survived in the milling process, was observed. Sintering of the powder compacts for 4 h showed relative densities of 80.7% at $1300^{\circ}C$ and 97% at $1400^{\circ}C$, respectively. Densification was found to almost complete at $1500^{\circ}C$, resulting in a dense and homogeneous microstructure with a relative density of 99.5%.

• Korean journal of food and cookery science
• /
• v.20 no.4
• /
• pp.409-417
• /
• 2004

The purpose of this study was to investigate the quality characteristics of Kugija-Injeulmi by varying the ingredient ratio of Lycii fructus powder (4, 6 and 8%). According to sensory evaluation of Kugija-Injeulmi, as the ratio of Lycii fructus powder was increased, the bitterness, hardness and chewiness all increased. It was found that Kugija-Injeulmi made of glutinous rice was moistened and softened with the addition of more Lycii fructus powder, but it was rougher than Kugija-Injeulmi made of glutinous rice flour. As a result of textural analysis of Kugija-Injeulmi, the hardness, adhesiveness, gumminess and chewiness increased as the amount of Lycii fructus powder increased, whereas the cohesiveness decreased. Kugija-Injeulmi made of glutinous rice was moister than Kugija-Injeulmi made of glutinous rice flour. The overall-acceptability was negatively correlated with coarseness. The overall-acceptability of Kugija-Injeulmi made of glutinous rice was much higher than that made of glutinous rice flour. From the above results, the most advisable mixture ratio of Kugija-Injeulmi is as follows Kugija-Injeulmi add 282g (94%) glutinous rice flour, Lycii fructus powder 18g (6%) and salt 3g. The moisture content was 42.22%.