• Journal of the Microelectronics and Packaging Society
• /
• v.9 no.2
• /
• pp.19-25
• /
• 2002

Glass composed of $Li_2$O.MgO. $MgF_2$.$SiO_2$.$B_2O_3$ for the fabrication of green sheet was prepared by melting process, and glass ceramics was prepared by the process of nucleation and grystal growth for the glass of $Li_2$O.MgO. $MgF_2$.$SiO_2$.$B_2O_3$ system with Lithium fluorhectorite and Lithium boron fluorphlogopite crystal phase. Powderization of the glass ceramics was carried out by water swelling. The average particle size at this point was 2.574 $\mu\textrm{m}$. Slurry was prepared for green sheet using high viscous sol fabricated by water swelling, which shows cleavage phenomenon in prepared glass ceramics. The optimum ratio of powder to water for the tape casting was 18:100, and its viscosity was 11,000~14,000 cps.

• Journal of Powder Materials
• /
• v.21 no.6
• /
• pp.460-466
• /
• 2014

Al-Si-SiC composite powders with intra-granular SiC particles were prepared by a gas atomization process. The composite powders were mixed with Al-Zn-Mg alloy powders as a function of weight percent. Those mixture powders were compacted with the pressure of 700 MPa and then sintered at the temperature of $565-585^{\circ}C$. T6 heat treatment was conducted to increase their mechanical properties by solid-solution precipitates. Each relative density according to the optimized sintering temperature of those powders were determined as 96% at $580^{\circ}C$ for Al-Zn-Mg powders (composition A), 97.9% at $575^{\circ}C$ for Al-Zn-Mg powders with 5 wt.% of Al-Si-SiC powders (composition B), and 98.2% at $570^{\circ}C$ for Al-Zn-Mg powders with 10 wt.% of Al-Si-SiC powders (composition C), respectively. Each hardness, tensile strength, and wear resistance test of those sintered samples was conducted. As the content of Al-Si-SiC powders increased, both hardness and tensile strength were decreased. However, wear resistance was increased by the increase of Al-Si-SiC powders. From these results, it was confirmed that Al-Si-SiC/Al-Zn-Mg composite could be highly densified by the sintering process, and thus the composite could have high wear resistance and tensile strength when the content of Al-Si-SiC composite powders were optimized.

• Journal of the Korean Electrochemical Society
• /
• v.15 no.2
• /
• pp.67-73
• /
• 2012

Spherical lithium manganese oxide spinel, $LiMn_{2-x}M_xO_4$ (M = Al, Mg, B) prepared by wet-milling, spray-drying, and sintering process has been investigated as a cathode material for lithium ion batteries. As-prepared powders exhibit various surface morphologies and internal density in terms of boron (B) doping level. It is found that the dopant B drives the growth of the primary particle and minimizes the surface area of the powder. As a result, the dopant enhances the internal density of the particles. Electrochemical tests demonstrated that the capacity of the synthesized material at 5 C could be maintained up to 90% of that at 0.2 C. The cycle performance of the material showed that the initial capacity was retained up to 80% even after 500 cycles under the high temperature of $60^{\circ}C$.

• Food Science and Preservation
• /
• v.20 no.6
• /
• pp.863-870
• /
• 2013

This study was conducted to investigate the quality characteristics of kimchi with Allium hookeri powder (AHP) added during eight weeks fermentation at $4^{\circ}C$. AHP was added to salted cabbage at concentrations of 0, 0.1, 1, and 5% (w/w). The quality characteristics of the AHR-added kimchi were determined by measuring pH, acidity, salinity, reducing sugar, microbial amounts, and sensory properties. The vitamin $B_1$ and vitamin C contents of the Allium hookeri root were 0.04 mg/100 g and 5.76 mg/100 g, respectively. As for the mineral contents, the K content was highest, followed by the Ca, Mg, and Fe contents. The pH was higher in the kimchi with 0.1%, 1%, and 5% AHP than in the kimchi without AHP during the eight-week fermentation. The salinity ranged from 2.02% to 2.37% over the eight weeks. The microbial cells and lactobacilli increased rapidly throughout the fermentation in the exponential phase and hardly increased in the stationary phase. In the sensory evaluations, the overall acceptance, taste, and texture of the kimchi with 1% AHP added were highest. In conclusion, the kimchi with 0.1%, 1%, and 5% AHP generally showed better quality than the kimchi without AHP. Especially, the kimchi with 1% AHP had the best scores in quality and overall acceptance during the fermentation.

• Journal of Environmental Health Sciences
• /
• v.22 no.3
• /
• pp.98-102
• /
• 1996

This study investigated performance of the phenol degradation and reaction characteristics according to variation of phenol volumetric loading rates and dilution rates in suspension and PACT reactors using Pseudomonas sp. B3. 1. Removal efficiencies of the PAC unit indicated about 100 % with phenol volumetric loading rates from 0.4 phenol $kg/ma^3\cdot d$ to 1.2 phenol $kg/m^3\cdot d$, however, which of the suspension reactor showed about 100% with from 0.2 phenol $kg/m^3\cdot d$ to 0.75 phenol $kg/ma^3\cdot day$. 2. The cell density slightly was decreased from 298.2 mg/l to 272 mg/l, when dilution rate for suspension was reactor increased from 0.4 to 1.41 1/d, and also the cell density suddenly was decreased to 145.5 mg/l and was washed out at the dilution rate higher than 1.60 1/d. But the cell density for the PAC unit was linearly decreased with dilution rate of from 0.8 to 3.0 1/d, and showed 220.75 mg/l at maximum dilution rate. 3. The phenol utilization rate was increased from 0.008 to 0.031 phenol g/l$\cdot$h, when dilution rate for suspension reactor was increased from 0.4 to 1.5 1/d, however, the rate for the PAC unit was linearly increased from 0.017 to 0.061 phenol g/l$\cdot$h as variation changes from 0.017 to 0.061 phenol g/l$\cdot$h dilution rate.

• Journal of the East Asian Society of Dietary Life
• /
• v.12 no.1
• /
• pp.15-22
• /
• 2002

This study was carried out to investigate antimutagenic and cytotoxic effects of Korean traditional Mackjang added with sea tangle powder. The content percentage of most of minerals among general composition increased by adding sea tangle powder. By the Ames test, the antimutagenic effect of ethanol extract of Korean traditional Mackjang added with 5% sea tangle powder was strongest exceeding the control, 10%, and 15% sea tangle additions. The ethanol extract (400$\mu$g/plate) of Mackjang added with 5% sea tang1e powder in the S. typhimurium TA 100 strain showed inhibition rate of 95.0% against the mutagenesis induced by MNNG. The inhibition rate of ethanol extract (400$\mu$g/plate) of Mackjang added with 5% sea tang1e powder in the S. typhimurium TA98 and TA100 strains was 81.4% and 88.8%, respectively, against the mutagenesis induced by 4NQO. Under the same conditions, the suppression against B($\alpha$)P and Trp-P-1 in the TA98 and TA100 strains were 85.3% and 91.0%, and 96.5% and 96.5%, respectively. For the anticancer effects, an investigation was done on the cytotoxicity of Mackjang added with 5% sea tangle powder on the cell lines with human lung carcinoma (A549), human hepatocellular carcinoma (HepG2), and human gastric carcinoma (KATOIII). The cytotoxicities were inhibited with increasing the extract concentration. The treatment of 1.0 mg/mL Mackjang added with 5% sea tang1e powder showed relatively strong cytotoxicity of 61.2%, 61.8% and 66.8% against A549, KATOIII, and HepG2, respectively.

• Journal of the Korean Ceramic Society
• /
• v.34 no.2
• /
• pp.175-180
• /
• 1997

새로운 복합페로브스카이트계 고용체 (1-x)Ba(Mg1/3Ta2/3)O3-xLa(Mg2/3Ta1/3)O3(x=0.0-1.0)를 설계하고 조성에 따른 고용체의 결정구조의 변화 및 MPB(Morphotropic Phase Boundary)를 분말 XRD를 이용하여 분석하였다. 초격자회절선의 변화로부터 MBT에 10mol%의 LMT를 치환함에 따라 1:2에서 1:1로의 규칙화타입의 전이가 일어남을 알 수 있었다. 면심입방정구조 영역(0.10.8조성의 경우, 주회절선의 피이크분리 및 새로운 회절선들로부터 격자비틀림의 형태가 단사정임을 알 수 있었다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.8
• /
• pp.523-530
• /
• 2019

This study was performed to develop Sulgidduk prepared with different levels (0, 3, 6, 9 and 12%) of defatted mealworm powder and to evaluate the characteristics of this Sulgidduk. We performed an assessment of color values, mechanical properties, general compositions and branched amino acids of Sulgidduk prepared with different levels of defatted mealworm powder. For the color values, the lightness(L) was decreased with increased amount of defatted mealworm powder, while the redness(a) and yellowness(b) were relatively increased. For the mechanical properties, the hardness and gumminess were significantly increased according to the increased amounts of defatted mealworm powder, but the chewiness, springiness and cohesiveness showed significant differences. For the sensory evaluation, the overall quality of Sulgidduk prepared with 6% defatted mealworm powder (MS-6) was higher as compared with that of the other Sulgidduk samples. For the general composition, the moisture and crude ash contents of MS-6 did not shown differences, while the crude protein was higher than those of the control, and the carbohydrate content of the control was higher than that of the MS-6. The contents of branched amino acids (valine, leucine and isoleucine) of MS-6 were higher than those of the control. Therefore, it was concluded that MS-6 could be a protein rich food as a good source of branched amino acids such valine, leucine and isoleucine.

• The Korean Journal of Food And Nutrition
• /
• v.30 no.3
• /
• pp.609-617
• /
• 2017

This experiment was carried out to enhance the availability of blackberry. Since it is difficult to use blackberry as a fresh fruit, we investigated the quality characteristics of blackberry powder obtained by various drying methods (freeze drying and hot-air drying at $40{\sim}80^{\circ}C$). The L- and b-values of freeze-dried powder was higher than hot-air dried powder. The pH (3.2) was lowest and the acidity (14.4%) was highest in freeze-dried powder. In freeze drying, the brix degree was $65.7^{\circ}Bx$, but it increased from $54.7^{\circ}Bx$ to $68.5^{\circ}Bx$ with increasing temperature during hot air drying. The total polyphenol and flavonoids contents were the highest in freeze-dried powder, at 9.3 and 6.2 mg/g, respectively. The levels increased as temperature increased in hot air drying. Anthocyanin content in freeze-dried powder was 8.51 mg/g, while it sharply decreased to 1.17~2.45 mg/g in hot-air drying. Vitamin C content in freeze drying ($979.4{\mu}g/g$) was higher than that in hot-air drying ($48.3{\sim}303.2{\mu}g/g$). The sample concentration required for 50% reduction of DPPH free radical scavenging ($RC_{50}$) was $79.7{\mu}g/mL$ in freeze drying, and showed high antioxidant activity. Also it decreased from $122.4{\mu}g/mL$ to $87.7{\mu}g/mL$ with temperature increase during hot air drying. We therefore conclude from the above results that freeze drying is more suitable for the production of blackberry powder, because this method showed high value of chromaticity, total polyphenol, flavonoid, anthocyanin content, vitamin C and antioxidant activity.

• Journal of the Korean Ceramic Society
• /
• v.40 no.5
• /
• pp.447-454
• /
• 2003

Samples were prepared by the solid-state reaction method. The nominal composition of the samples was B $i_{1.84}$P $b_{0.34}$S $r_{1.91}$C $a_{2.03}$C $u_{3.06}$ $O_{10+{delta}$ prepared from powder of B $i_2$ $O_3$, PbO, SrC $O_3$, CaC $O_3$, and CuO. They were pulverized, mixed with AgO, A $u_2$ $O_3$and MgO of 50 wt%. Finally, they were sintered at 820 to 85$0^{\circ}C$ in air. The structural characteristics, the microstructure of surface and the critical temperature with respect to the each samples were analyzed by XRD, $T_{c}$, SEM and EDS respectively. It was found that the the critical temperature of the silver oxide additive samples (99.58 K) is higher than those of gold or magnesium oxides additive samples, but all those values are lower than that of pure Bi-2223 phase. The microstructure of surface showed the tendency which the AgO additive samples become more minuteness than A $u_2$ $O_3$ and MgO additive samples.s.samples.s.