• Journal of the Korean Society for Heat Treatment
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• v.31 no.3
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• pp.126-134
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• 2018

In this research, we produced polycrystalline n-type $Bi_2Te_{2.7}Se_{0.3}$ powder using water atomization. To obtain full benefit through water atomized powder, we have implemented spark plasma sintering and hot extrusion for powder compaction. The microstructure and thermoelectric properties were investigated and compared. The average grain size of SPS and extruded bulks were 3.08 and $3.86{\mu}m$ respectively. The extruded material microstructure contains layered grains with less grain boundaries and its counter-part SPS displays dense packed grains with high grain boundaries. Among both bulks, extrusion sample exhibited high power factor (PF) of $2.96{\times}10^{-3}Wm^{-1}K^{-2}$ which is 38% higher than SPS ($2.14{\times}10^{-3}$) bulk sample. Due to variations in grain size and grain boundaries, the SPS bulk shows low thermal conductivity than extruded bulk. However, the extruded bulk sample exhibited a peak ZT of 0.69 at 400 K, which is 19% higher than SPS bulk sample, due to its higher power factor.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.1
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• pp.51-56
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• 2012

In the present study, we investigated the effect of mechanical alloying (MA) on the formation of amorphous VCo system through solid state reaction during ball milling. Two types of powder samples, ${\sigma}$-VCo intermetallic compound and $V_{50}Co_{50}$ powder mixture, were applied as a starting materials. With increasing milling time, a structural characteristics into the amorphous state is distinctly observed from the structural factor and radial distribution by X-ray diffraction. Amorphization has been observed in all two types of samples after the milling for 120 hrs. DSC spectrum of $V_{50}Co_{50}$ powder sample milled for 60 hrs indicates a sharp exothermic peak from the crystallization at $600^{\circ}C$. The structure factor, S(Q) and radial distribution function, RDF(r), observed by X-ray diffraction gradually change into a structure characteristic of an amorphous state with increasing MA time.

• The Korean Journal of Food And Nutrition
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• v.32 no.6
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• pp.651-661
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• 2019

Suaeda asparagoides (Miq.) is a salt marsh plant, long been prescribed in traditional medicine for the treatment of hypertension and liver toxification in Asian countries. The powder of S. asparagoides was added at the ratio of 0, 5, and 10%, respectively, of grain-type Meju to manufacture Doenjang in brine according to the salt concentration (8 and 12%). After 24 weeks of fermentation, the Doenjang samples were determined to have an anti-inflammatory effect on RAW 264.7 cells. Evaluation of the anti-inflammatory effect of Doenjang added S. asparagoides powder extracted using 80% EtOH, was performed to study the inhibition of pro-inflammatory factors such as NF-κB (nuclar factor κB), NO (nitric oxide), TNF-α (tumor necrosis factor alpha), IL-6 (interleukin-6), iNOS (inducible nitric oxide synthase), and COX-2 (cyclooxygenase-2) in lipopolysaccharide (LPS)-induced RAW 264.7 cells. The results showed that the Doenjang extracts reduced the production of NO, IL-6, COX-2, and iNOS increased in the LPS-stimulated RAW cell without cytotoxicity. In the case of the NF-κB and TNF-α there was no significant difference between the control and samples. In conclusion, these results suggest that Doenjang added with the S. asparagoides powder acts as functional fermented food with anti-inflammation effect.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.377-383
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• 2013

Premature-green rice is typically obtained by early harvest when culms of rice still appear green in color, and the rice and its food products have been considered as wellbeing foods. This study was carried out to determine the quality characteristics of cookies made from flour added with 10, 20, and 30% whole green rice powde r(WGRP) of two kinds of Hopum and Shinsun waxy rice. The quality characteristics of cookies, including pH, spread factor, color, hardness, and sensory properties, were estimated. WGRP with different levels of 10, 20, and 30% was added into powder for preparing cookies, and their quality properties were evaluated. The pH and hardness of the cookies increased, while spread factor showed highest added with 20% Hopum and Shinsun waxy rice. The color (L) of cookies decreased 20% added with Hopum and Shinsun waxy rice. The sensory properties of cookies was highest added with 20% Hopum and 10% Shinsun waxy rice. The result of this study suggest that addition of 20% Hopum and 10% Shinsun waxy rice are available rice cookies. It was concluded that WGRP may have a potential in bakery industry as a new food material.

• The Korea Journal of Herbology
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• v.24 no.3
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• pp.69-77
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• 2009

Objectives : This study was designed to investigate the effects of horse bone powder extract on the growth of longitudinal bone in adolescent male rats. Methods： Longitudinal bone growth was measured by fluorescent microscopy. To examine the effects on the growth plate metabolism, the total height of growth plate, the induction of local insulin-like growth factor-1 (IGF-1), and bone morphogenetic protein-2 (BMP-2) were measured. Results： Horse bone powder extract enhanced longitudinal bone growth and total height of the growth plate. Also, it promoted the induction of local IGF-1 and BMP-2 of the growth plate. Conclusions： This study shows that the horse bone powder extract effects longitudinal bone growth in adolescent rats and might be used for both stunted adolescents and inherent growth failure patients.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.4
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• pp.223-231
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• 2022

Residual stress that can occur during the metal additive manufacturing process is an important factor that must be properly controlled for the precise production of metal parts through 3D printing. Therefore, in this study, the factors affecting these residual stresses were investigated using an experimental method. For the experiment, a specimen was manufactured through an additive manufacturing process, and the amount of deformation was measured by cutting it. By appropriately calibrating the measured data using methods such as curve fitting, it was possible to quantitatively analyze the effect of process parameters and metal powder reuse on deformation due to residual stress. From this result, it was confirmed that the factor that has the greatest influence on the magnitude of deformation due to residual stress in the metal additive manufacturing process is whether the metal powder is reused. In addition, it was confirmed that process parameters such as laser pattern and laser scan angle can also affect the deformation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1813-1820
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• 2013

This study is conducted to investigate the quality characteristics of cookies containing different levels (0%, 20%, 40%, 60%) of brown rice powder with enhanced levels of GABA (${\gamma}$-amino butyric acid). The pH of cookie dough was higher in cookies containing brown rice powder. A proximate composition analysis showed that the moisture content was increased with the addition of the brown rice powder, yet there was no significant difference in the crude protein and crude fat contents among the added groups. The ash content was the highest in the 60% added group. The spread factor of the control cookie was higher than that of cookies containing 40% and 60% brown rice powder. The incorporation of brown rice powder in cookies lowered the lightness and yellowness values, but increased the redness value. The hardness of the cookies was lower in 40% and 60% added groups than that of the controls. The GABA content in the brown rice added groups was higher than that of the control cookie, and increased as brown rice powder increased. A consumer acceptance test revealed that there was no significant difference in the overall preference scores among the cookies. From these findings, it is suggested that the cookies with brown rice powder up to 60% added can be developed as goods.

• Mass Spectrometry Letters
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• v.7 no.4
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• pp.102-105
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• 2016

This study explored the feasibility of using a carburization technique to enhance the ion intensity of isotopic analysis of ultra-trace levels of uranium using thermal ionization mass spectrometry (TIMS). Prior to fixing uranium samples on TIMS filaments, graphite powder suspended in nitric acid was deposited on rhenium filaments. We observed an enhancement of $^{238}U^+$ intensity by a factor of two when carburization was used, and were able to roughly optimize the amount of graphite powder necessary for carburization. The positive shift in heating current when evaporating filaments upon carburization implies that uranium was chemically altered by carburization, when compared to normal fixation processes. The good agreement between our method and known standards down to an ultra-trace level shows that the proposed technique can be applied to isotopic uranium analysis down to abundances of ~10 pg.

• Journal of the Korean institute of surface engineering
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• v.40 no.3
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• pp.131-137
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• 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.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.6
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• pp.957-962
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• 2010

This study examined the effects of Cornus fructus addition to suger snap cookies on WRC (water rentention capacity) and AWRC (alkaline water retention capacity). WRC and AWRC increased as more Cornus fructus powder was added, whereas the sedimentation value and Pelshenke value decreased. Regarding cookie color, L value decreased, whereas the a and b values increased. As the cookie diameter became smaller, thickness increased and spread factor decreased. Hardness of the cookies decreased, and preference was highest for cookies with 5% added Cornus fructus. The preferences for cookies were in the following order: 7% < 3% < 1% < 0% < 5% addition. In conclusion, addition of less than 5% Cornus fructus powder was the most desirable. To complement cookie appearance, it seems necessary to adjust the water content of Cornus fructus powder or add an emulsifier.