• Journal of the Korean Ceramic Society
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• v.26 no.1
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• pp.100-108
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• 1989

Aluminum hydroxides were prepared by the alkoxide hydrolysis method using Al-isopropoxide as a starting material and NH4OH as a catalytic agent. When Al-isopropoxide was hydrolyzed in a H2O-NH3 system, only Al(OH)3 was obtained over all pH values. However, AlOOH was formed besides Al(OH)3 when Al-isopropoxide was hydrolyzed in a H2O-NH3-isopropyl alcohol system. The AlOOH/Al(OH)3 ratio was increased as the isopropyl alcohol content was increased. The hydroxides, Al(OH)3 and AlOOH, obtained in this study and the commerical products, $\alpha$-Al2O3 and AlOOH were subjected to the carbothermal reduction and nitridation reaction to product AlN powder, using carbon black as a reducing agent under N2 atmosphere at various temperatures. AlN was synthesized from the obtained Al(OH)3 and the commercial AlOOH at 145$0^{\circ}C$, however, synthesized from the obtained AlOOH and the commercial alpha-alumina at 135$0^{\circ}C$. The temperature difference is assumed to be attributed to the reactivity of those powders. AlN powder prepared from the Al-isopropoxide was observed to have the narrower particle size distribution than that prepared from the commercial $\alpha$-Al2O3 or AlOOH.

• Polymer(Korea)
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• v.26 no.2
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• pp.270-278
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• 2002

In this study, the fracture behavior by low velocity impact damage and the tendencies of impact energy absorption were investigated. Low velocity impact tests were performed using a mini tower drop weight impact tester, and graphite powder, carbon black and milled carton fiber were chosen as additives. Addition of graphite powder increased the maximum load and maintained the stress long until the total penetration happened. At the content of 9 vol%, they showed the maximum of 42% improvement in impact strength compared composites containing no additives. At the test with low impact energy of 0.4 J, impact energy was consumed by delamination in the composite containing no additives, however, as graphite contents increased, the tendency of failure changed to the penetration of the specimen.

• Journal of the Korean Society of Food Culture
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• v.7 no.1
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• pp.81-90
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• 1992

The Guk had lessened to use Gang, Whak, Tang. The Guk was classified into cooking method as a soup stock, the used main substances, and the temperature of the Guk. According to the soup stock were divided clear soup, Tojangguk, and Gooumguk. Another classification of Guk by main substances were Yuktang (meat soup), Otang (fish soup), bongtang (poultry soup), Shotang (vegetable soup), Japtang (vary substance soup) and Yonpotang (soybean-curd soup), and by the temperature of the Guk were divided Doounguk (warm soup) and Naengguk (cold soup). In the thesis, according to the kinds of Tojangguk, the reference frequency to them, the adding foods in them, and the variety cooking method in the Tojangguk were analyzed by the cook books published from 1700 to 1988 in Korea. 1. There were 29 kinds of Tojangguk. 2. The main substances of Tojangguk were meat, poultry, fish, shellfish, vegetable, mushrooms and seasonings. 3. The Tojangguk was boiled with the rice water and fermented soybean paste and fermented soybean-pepper powder paste. For the development of taste were added beef, shellfish, dried anchovy, dried small prawn, and soup stock of beef bones in winter. Seasoning substances were green onion, garlic, black pepper, sesame powder and oil.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1149-1150
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• 2006

The oxidation of (W,Mo)$Si_2$ powders has been investigated at 400, 500 and $600^{\circ}C$ for 12.0 hours in air. It was shown that the low temperature oxidation resistance of (W,Mo)$Si_2$ was worse than that of $MoSi_2$, and they showed great changes in mass, volume and colour. Especialy at $500^{\circ}C$, the amount of volume expansion of (W,Mo)$Si_2$ was as high as about $7\sim8$ times and color changed from black to yellow after 4.0h with $MoO_3$, $WO_3$, (W,Mo)$O_3$ and amorphous $SiO_2$ as main reaction products. The mass gain and oxidation rate were relatively slower at $400^{\circ}C$ and $600^{\circ}C$ than that at $500^{\circ}C$.

• Advances in nano research
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• v.13 no.6
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• pp.527-543
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• 2022

A novel, green, versatile and magnetically retrievable BiFeO₃/CDR (Bismuth ferrite/coriander) nanocomposites were fabricated via simple wet chemical method utilizing in situ functionalized, cheap coriander seed powder (CDR 5%, 10%, 15% and 20 wt%) as a fuel to enhance the efficiency of pristine BiFeO₃. A comparative study was performed between BiFeO₃/CDR and BiFeO₃/CNT (Bismuth ferrite/carbon nanotubes) nanocomposites for the removal of various hazardous pollutants from waste water. The successful synthesis of the fabricated nanomaterials was monitored via FT-IR, Powder XRD, FE-SEM, CV, VSM, CHNS/O and XPS studies. The synthesized nanomaterials were employed for the oxidative degradation of Carbol fuchsin, Reactive black 5, Ciprofloxacin and Doxorubicin; adsorption of a pesticide malathion; and reduction studies for Para-nitrophenol (PNP). The fabricated nanomaterials (BiFeO₃/CDR) showcased excellent efficiency and comparable results with (BiFeO₃/CNT) for the removal of model pollutants. Moreover, synthesized green heterojunction was also testified for mixture of textile and pharmaceutical waste. Hence CDR can be utilized as a better alternative of CNTs.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.38-46
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• 2010

C3GHi, a novel black rice variety developed by conventional breeding has more high contents of cyanidine-3-glucoside (C3G) and a more strong antioxidant than normal black rice. In this study, we investigate the antioxidative potential and anti-diabetic activity of C3GHi and extract of it for the purpose of development of functional materials or replacement meal for diabetic patients. Using in vitro antioxidative activity assay system such as DPPH radical quenching assay, superoxide anion radical scavenging assay, inhibition of lipid peroxidation and DNA breakage assay, C3GHi extract was observed to have more high antioxidative activity than normal black rice breed. The glycemic index of a freeze dried powder of C3GHi brown rice showed $43.7\pm18.8$, which belonged to low GI food (GI of 55 or less). Using in vivo diabetic model such as db/db mice model and streptozotocininduced diabetic model, C3GHi rice extract decrease blood glucose level and inhibit oxidative stress in blood. From the results, we think that the C3GHi varieties have a potential for the functional materials or ingredient of meal replacement for diabetic patients.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.65-69
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• 2010

This study was carried out to investigate the antioxidative and anti-inflammatory activity of crude anthocyanin compounds extracted from black soybean. The crude anthocyanin compounds were extracted with 80% methanol and concentrated to powder. The most abundant compound isolated from the extract was C3G(cyanidin-3-glucoside). The superoxide dismutase (SOD) assay was conducted to assess the antioxidative activity of the crude extract. SOD, which catalyzes the dismutation of the superoxide anion into hydrogen peroxide and molecular oxygen, is one of the most important antioxidative enzymes. The black soybean anthocyanin extracts inhibited more than 90% of the superoxide radical at a concentration of 0.1% and 100% at a concentration of 0.5%, indicating that this extract displayed excellent antioxidative activity. To assess the anti-inflammatory activity of the extract, a NO(Nitric oxide) production assay in RAW 264.7 cells was performed. NO is an important physiological messenger and effector molecule in many biological systems, including immunological, neuronal and cardiovascular tissues. In this assay, the anthocyanin extracts showed a high anti-inflammatory potential, where the inhibitory potency for NO production was similar to the positive control, particularly for EGCG(epigallocatechin-3-gallate), which is known to have excellent anti-inflammatory activity. Thus, it can be concluded that the anthocyanin extracts from black soybean have distinctive pharmaceutical activities and may be used as an excellent source materials to supplement the health benefits of various food products.

• Journal of Dairy Science and Biotechnology
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• v.33 no.2
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• pp.159-166
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• 2015

We investigated the anti-obesity effects of Lactobacillus acidophilus C isolated from kimchi and red ginseng and black raspberry mixture fermented by this strain. Experimental samples were prepared with 10% skim milk, 1% red ginseng extract and 1% immature black raspberry powder and without red ginseng extract and black raspberry fermented by this strain at $37^{\circ}C$ for 24 hour. Male C57BL/6J mice were randomly divided into 4 groups (a normal diet group (N), a high-fat diet group (HF), a high fat diet with L. acidophilus C (C), and a high fat diet with fermented mixture (CEx)) and were orally administered daily for 6 weeks at concentration of 2,000 mg/kg body weight. The results showed that weight gain, weight of periepididymal fat and perirenal fat, adipocyte size, lipid accumulation in liver, serum glucose concentration, serum GOT and GPT concentration and serum leptin were decreased and concentration of HDL-cholesterol and serum adiponectin were increased compared to HF group. These results suggest that fermented mixture (CEx) might be helpful in improvement of high-fat diet-induced obesity than only L. acidophilus C intake.

• Resources Recycling
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• v.29 no.6
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• pp.65-72
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• 2020

Black dross is a dark gray dross generated during the aluminum recycling process that uses flux, and contains NaCl, KCl, Al2O3, MgO, etc. Black dross is separated into soluble substances (NaCl, KCl) and insoluble substances (Al2O4, MgO) through the dissolution process. Soluble materials can be reused as salt flux, and Al2O3 and MgO can be upcycled to various ceramic materials through the synthesis process. In this study, Mayenite was synthesized using Al2O3 and MgO recovered from black dross, and the synthesis was performed according to the mixing ratio and reaction temperature. It was confirmed that when Mayenite was synthesized using black dross (spinel) and CaCO3, precursors were changed to Mg0.4Al2.4O4 and CaO at 700 ℃, and to Ca12Al14O33 (Mayenite) after 800 ℃. In the mixing conditions experiment, it was confirmed that the Mayenite XRD peak increased with increase of the CaCO3 content, and the Mg0.4Al2.4O4 XRD peak decreased. As a result of the BET analysis of the synthesized powder, the surface area decreased as the fine particles were grown and agglomerated in the process of generating mayenite.

• Journal of Life Science
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• v.23 no.3
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• pp.432-442
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• 2013

In this study, we examined the biological activity and synergistic effects of an extract powder of 1% and 3%, each fresh (FGP) and black garlic (BGP) in streptozotocin-induced diabetic rats. Blood glucose content was significantly lower in FGP and BGP groups than control group. Glycosylated Hb was significantly higher in streptozotocin induced diabetic control group than normal group, but significantly lower in FGP and BGP groups. Total cholesterol content of the FGP and BGP groups were lower than control group, but not shown the significant difference between garlic fed groups. HDL-cholesterol concentrations of the FGP and BGP fed groups were significantly higher than control group, except of 1% BGP group. LDL and VLDL-cholesterol contents were significantly lower in 3% FGP group, and the same tendency atherogenic index and cardiac risk factor. GOT, GPT, and ${\gamma}$-GTP activity of serum were lower in FGP and BGP fed groups than control group. Glycogen contents in liver significantly higher than control group, and has not significantly difference between normal group. TBARS content was no significantly difference in the liver and serum, but in the kidney, 3% FPG and BGP fed groups were significantly lower than other experimental group. DPPH radical scavenging activity of liver has not significant difference among experimental groups, but activity was higher garlic extract powder fed groups in serum and kidney. These results indicate that dietary supplements of fresh and black garlic extract powder was contributed to lower of blood glucose, loss prevention of glycogen in liver and improve of lipid metabolism.