• 한국초전도ㆍ저온공학회논문지
• /
• 제8권3호
• /
• pp.13-17
• /
• 2006

The effect of the addition of the nano size $Y_2O_3$ powder on the microstructurte and superconducting properties of YBCO thin film deposited on LAO single crystalline substrate by TFA-MOD method was studied. Nano size $Y_2O_3$ powder was added to the stoichiometric precursor solution with a cation ratio of Y : Ba . Cu = 1 : 2 : 3 prepared using TFA as chelating agent. Precursor solutions with and without $Y_2O_3$ addition were coated on $LaAlO_3(100)$ single crystalline substrates by dip coating method. Calcination and conversion heat treatments were performed in controlled atmosphere containing moisture Current carrying capacity(Jc) of YBCO film was enhanced about 50% by $Y_2O_3$ doping and it is thought to be due to the better connectivity of YBCO grains and/or the flux pinning by the $Y_2O_3$ particles embedded in YBCO grains.

• 한국식품저장유통학회지
• /
• 제31권4호
• /
• pp.565-578
• /
• 2024

This study investigated the physicochemical quality, antioxidant activity, instrumental sensory characteristics of nurungi prepared from rice and dried-radish root bugak powder (DRBP). DRBP was made from dried-radish root bugak (DRB) coated with 80% superfine glutinous and 20% non-glutinous rice powders. The nurungji food products were prepared using 80% non-glutinous rice and 20% glutinous rice, and DRBP, which was added at different levels of 2, 4, 6, 8, and 10%, respectively (NR-2, NR-4, NR-6, NR-8, and NR-10). The total polyphenol and flavonoid contents were increased from 21.34 to 27.87 mL, and 7.46 to 20.05 mgNE/mL respectively, as the amounts of DRBP increased. Color L^*-value, pH, and hydration properties were decreased with the increased amounts of DRBP. The electronic tongue results showed that NR-6 sample had high umami scores and sourness compared to the control sample (NR-0). Furthermore, SEM images indicated different shapes between the control (NR-0) and other treatments. However, no differences among nurungji treated with DRBP. Therefore, the use of DRB coated with superfine glutinous and non-glutinous rice powders is a viable ingredient for nurungji preparation. This study shows that adding 6% DRBP produced nurungji with good- quality physicochemical and sensory characteristics.

• The International Journal of Costume Culture
• /
• 제8권2호
• /
• pp.124-131
• /
• 2005

This study focused on the change of skin temperature by the emissivity and emission power of far-infrared for conformant far infrared effect to naked eyes. The study method is to manufacture the bra pad by each concentration on far-infrared materials of illite powder $(K,H_3O)AI_2(Si,Al)_4O_{10}(H_2O,OH)_2)$, liquid alumina ($Al_2O_3$), the extracted liquid from 29 kind of medical plants, then, measured change of skin temperature. Result are as follows. Far-infrared were emitted each $90.2\%,\;90.1\%,\;89.7\%$ from the illite powder, liquid alumina, extracted liquid from medical plants. When the testee weared the bra pad, the temperature of coated bra pad was $0.5^{\circ}C$ higher than the non finished bra pad. Washing fastness on far-infrared finishing was better dope addition method than coating method.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회A
• /
• pp.166-171
• /
• 2007

The characterization of monolithic SiC and SiCf/SiC composite materials fabricated by NITE and RS processes was investigated in conjunction with the detailed analysis of their microstructure and density. The NITE-SiC based materials were fabricated, using a SiC powder with average size of 30 nm. RS- SiCf/SiC composites were fabricated with a complex slurry of C and SiC powder. In the RS process, the average size of starting SiC particle and the blending ratio of C/SiC powder were $0.4\;{\mu}m$ and 0.4, respectively. The reinforcing materials for /SiC composites were BN-SiC coated Hi-Nicalon SiC fiber, unidirectional or plain woven Tyranno SA SiC fiber. The characterization of all materials was examined by the means of SEM, EDS and three point bending test. The density of NITE-SiCf/SiC composite increased with increasing the pressure holding time. RS-SiCf/SiC composites represented a great decrease of flexural strength at the temperature of $1000\;^{\circ}C.$

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
• /
• pp.836-837
• /
• 2005

In order to enhance discharge efficiency of Plasma Display Panel (PDP), we used an electride as electron emission layer for PDP during PDP discharge process. As the electride used in this study, $12CaO7Al_2O_3$, has low work function, it is expected to yield high electron emission during glow discharge process. $12CaO7Al_2O_3$ powder was synthesized from $CaCO_3$ and $Al(OH)_3$ powder and Ca treated for realization of electride characteristics. The $12CaO7Al_2O_3$ powder was coated on the surface of dielectric layer of PDP and discharge characteristics of electride material were evaluated.

• 한국표면공학회지
• /
• 제40권3호
• /
• pp.131-137
• /
• 2007

The typical MCFC (molten carbonate fuel cell) anode is made of Ni-10%Cr alloy. The work of this paper is focused concerning long life of anode because Ni-10% Cr anode is suffering from sintering and creep behavior during cell operation. Therefore, Ni-coated Alumina powder($20{\mu}m$) was developed by electroless nickel plating. Optimum condition of electroless nickel coation on $20{\mu}m$ alumina is as follows: pH 11.7, temperature $65{\sim}80^{\circ}C$, powder amount $100cm^2/l$. The deposition rate for Ni-electroless plating was as a function of temperature and activation energy was evaluated by Arrhenius Equation thereby activation energy calculated slope of experimental data as 117.6 kJ/mol, frequency factor(A) was $6.28{\times}10^{18}hr^{-1}$, respectively.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
• /
• pp.156-157
• /
• 2006

The preparation of composite powders for plasma spraying by an in-house designed mechanofusion process is investigated. Results show that dry particle coating depends on the chemical and mechanical properties of powders. In metal/oxide and metal/oxide/carbide powder mixtures, fine ceramic particles coat the surface of the metallic coarser particles. A nearly rounded shape of the final composite particles is induced by the mechanical energy input with no formation of new phases. However with the carbide/metal powdered system, only an intimate mixture of components is achieved. It is suggested that the coating mechanism is governed by agglomeration and rolling phenomena.

• 한국생활과학회지
• /
• 제22권5호
• /
• pp.461-476
• /
• 2013

This study aims to provide practical information of both color and hands of cotton fabrics dyed with persimmon dye powder for natural dyeing fashion industries by investigating dyeing behavior and color gamut, by testing mechanical properties depending on color characteristics, and finally by evaluating dyeing fastness. As results, the persimmon dye powder obtained by extracting the fruits to final solid powder was found as containing tannin and it partially coated between and on fibers similarly to traditionally dyed one. The K/S values of non-mordanted fabric and two differently mordanted ones with Fe and Cu seemed to reach their equilibrium from 800, 800, and 600% (owf), respectively. Yellow-red was the only one hue shown while tones were various as pale (p), light grayish (ltg), soft (sf), dull (d), grayish (g), and dark grayish (dkg). In mechanical properties, the dyed fabrics with p and ltg tended to be less altered than undyed ones whereas d and d kg by higher bath concentrations could be applied to boxy silhouette owing to their increased stiffness and less stretchability. Although fastness to dry cleaning and stain was good, color change by washing and rubbing needed to be improved.

• 한국세라믹학회지
• /
• 제32권8호
• /
• pp.909-914
• /
• 1995

From alumina powder and TEOS, $\alpha$-Al2O3/SiO2 composite powder for reaction-sintered mullite was synthesized by heterogeneous coagulation and surface coating, and investigated the mullitization reaction and sintering behavor of these powders. In $\alpha$-Al2O3/SiO2 composite powder prepared by heterogeneous coagulation, each alumina particles were surrounded by silica particles of 50~60 nm in size. And the alumina particles in composite powder prepared by surface coating were coated by uniform silica layer with thickness of 50 nm. In both methods, mullitization reaction was completed at 1$650^{\circ}C$ for 3h, and specimen sintered above 145$0^{\circ}C$ was about 95% fo the theoretical relative density. Mullite grains formed from the reaction with composite powders showed spherical shape with a size of 1~2${\mu}{\textrm}{m}$.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
• /
• pp.1249-1250
• /
• 2006

Cube textured Ni substrate were fabricated for YBCO coated conductors from the initial specimens prepared by powder metallurgy (P/M) and casting and the effects of annealing temperature and reduction ratio on texture formation and microstructural evolution were evaluated. The initial specimens were rolled and then annealed in the temperature at $600^{\circ}C{\sim}1200^{\circ}C$. A strong cube texture formed for P/M substrate, and the degree of texture did not significantly vary with annealing temperature of $600^{\circ}C{\sim}1100^{\circ}C$. On the other hand, the texture of casting substrate was more dependent on the annealing temperature and twin texture and several minor texture components started to form at $1000^{\circ}C$.