• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.3
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• pp.147-152
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• 2010

In this study, the artificial coarse aggregate was manufactured by using coal ash and low grade clay. The characteristics of a coal ash-clay system were investigated using XRD, XRF, TG-DTA, SEM and Dilatometer with various coal ash contents. The chemical compositions are the fly ash, bottom ash and clay, $Al_2O_3$ are 28.5 wt%, 32.4 wt% and 18.1 wt%, and $SiO_2$ are 33.0 wt%, 53.7 wt% and 68.4 wt% in weight ratio, respectively. The shrinkage of specimens started at around $850^{\circ}C$ and changed little up to $1100^{\circ}C$, but increased markedly at above $1100^{\circ}C$. The shrinkage rate is strongly related to the decarbonization amount of coal ash. At the sintering temperature $1150^{\circ}C$, it was found that quartz, mullite, anorthite and albite phase exist in all specimens. It was found that bottom-clay system specimen sintered at $1150^{\circ}C$ had a good compressive strength of 87.5 kg/$cm^2$, and the compressive strength of bottom-clay specimen was higher than that of fly-clay system specimen. The reusability of coal ash as a raw material in the process of shotcrete resources such as artifical coarse aggregate is highly expected.

• Korean Journal of Agricultural Science
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• v.24 no.1
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• pp.41-49
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• 1997

The results on the chemical characteristics of the pork fed with fermented feeds are summarized as follows; 1) The pork treated with fermented feeds had lower fat and higher protein content than control pork in proximate compositions. It is considered to be the improvement of the quality. 2) It was not recognized to the difference of oxidation level among the sample porks. 3) Oleic acid was the highest concentration in the components of fatty acid of pork. The rate of the saturated and unsaturated fatty acids is 38.8 % : 59.9 % in the ordinary meat, 40.8 % : 57.8 % in the a high-grade meat, and 36.3 % : 62.0 % in the pork treated with fermented feeds. In addition, the essential fatty acid content of them is 14 %, 11.2 %, and 16.7%, respectively. 4) Glutamic acid was the highest composition in total amino acids and the essential amino acid content was 39% in both an ordinary meat and the pork treated with fermented feeds, and 14 % in high-grade meat. 5) It was no difference in the inorganic content among the samples. The water holding capacity by extraction meat juice was higher to 92 % in the pork treated with fermented feeds and 15.6 % in a loss in quantity by heating than others. Thus, the pork bred with fermented feeds was evaluated to be good in terms of processing and cooking.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.8
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• pp.929-936
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• 2017

The purpose of this study was to compare the chemical components and biological activities of Salvia miltiorrhiza Bunge (SMB) from different cultivation regions (Gochang, Yeongyang, Jangheung, and China). Proximate compositions and contents of total polyphenols and flavonoids were measured. Depending on the cultivation region, proximate composition of SMB showed significant variations. Total polyphenol and total flavonoid contents were highest in Yeongyang SMB and Gochang SMB, respectively. We prepared hot water and 75% ethanol extracts of SMB from different cultivation regions and also investigated the biological effects of extracts on anti-oxidant, antibacterial, and anti-inflammatory activities. Extracts of Yeongyang SMB were the most effective at scavenging DPPH and ABTS free radicals, and hot water extract showed better scavenging activity than 75% ethanol extract. We observed that extracts of Yeongyang SMB exhibited the best antibacterial activity against Bacillus cereus, and 75% ethanol extract showed better antibacterial activity than water extract. Anti-inflammatory activities of SMB extracts from different cultivation regions were investigated through evaluation of their inhibitory effects on production of nitric oxide (NO) in lipopolysaccharides-induced RAW 264.7 cells. At $50{\mu}g/mL$, extract of China SMB showed the highest NO inhibitory activity of 34% among water extracts, and extract of Gochang SMB showed the highest NO inhibitory activity of 68% among 75% ethanol extracts. Salvianolic acid B level was the highest in extract of Yeongyang SMB with values of 110.59 mg/g for water extract and 111.93 mg/g for 75% ethanol extract.

• Journal of the Korean Applied Science and Technology
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• v.32 no.2
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• pp.348-361
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• 2015

To reduce the effects of greenhouse gas (GHG) emissions, the government has announced the special platform of technologies as parts of an effort to minimize global climate change, and the government distributed biodiesel since 2006 as the further efforts. Although there are some debates about some quality specifications and unbalanced of source (44% from palm oil), more than 400kton/year of biodiesel was produced in 2013. Moreover the amounts will be increased when the RFS is activated. To solve the unbalanced situation and to achieve the diversity of feeds, it is essential that many researches should be considered. Especially, free and bond glycerines are one of the important properties seriously affected to the combustion system in vehicle & cold properties. Previous method (KS M 2412) couldn't cover the biodiesel derived from lauric oil($C_{12:0}$) such as PKO (Palm Kernel Oil), Coconut oil because those compositions are lighter than other conventional biodiesel sources. In this study, we review the existed method and figure out the factors should improve to analysis the glycerine from PKO and Coconut oil biodiesel. Modifying the analysis conditions to enhance the resolution and change the internal standards to avoid the overlapped- peaks between Capric acid ME ($C_{10:0}$) and standard#1(1,2,4-butantriol). From this revised method, we could solve the restrictions of previous methods. And check the possibility of new method to analyze the glycerine in biodiesel regardless of sources.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.670-675
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• 2016

Both melting temperature and enthalpy of MBCA/DMTDA mixtures were measured as a function of DMTDA compositions using DSC. The thermal properties of polyurethane elastomer samples prepared with MBCA, DMTDA, and 40/60 MBCA/DMTDA mixture as curing agents were also observed using TGA. MBCA and DMTDA showed good miscibility over the entire composition range, exhibiting individual DSC melting peaks. Peak temperatures were non-linearly reduced as DMTDA concentrations increased, being approximately $60^{\circ}C$ in the case of the 40/60 MBCA/DMTDA mixture. Furthermore, melting enthalpy of the mixture was calculated as 3.8 J/g, which was only 4.3% compared to 87.3 J/g of MBCA. Based on these results, crystallization of the mixture was considered to occur very slowly, and the fluidic gel-state of the mixture was visually confirmed to be maintained over 5 days at room temperature. Thermal decomposition of polyurethane elastomer prepared with 40/60 MBCA/DMTDA curative started at about $190^{\circ}C$, which is similar to that observed for DMTDA, only except decomposition behavior over higher temperature of $400^{\circ}C$.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.849-859
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• 2000

This study was conducted to identify the characteristics of methane fermentation and lysis effects of pre-treated microalgae. Chemical compositions of microalgae showed that the VS(volatile solid) was 86.1% of TS(total solid), and the protein was 63.5% of VS. These values were higher than those of activated sludge. The cell lysis test of raw microalgae biomass was conducted by many physicochemical methods. presenting that the degree of cell lysis was affected by following order: ultrasonic(100min.), alkali(pH 13), ultrasonic(10min), thermal($120^{\circ}C$), thermal($50^{\circ}C$), and acidic(pH 3) treatment. Methane fermentation with many pre-treated samples was performed, showing that the concentration of acetic acid was the highest. followed by propionic acid, butylic acid and valerie acid among all VFA(volatile fattic acid). In methane production. ultrasonic samples were only more effective than untreated one in total gas and methane productivity. but other samples were less effective. Especially. the alkalic sample had an inhibitation effect on methanogens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.2
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• pp.255-260
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• 2016

This study aimed to investigate the effect of red pepper seed powder addition on the chemical compositions, cooking characteristics, and sensory properties of tteokgalbi. Tteokgalbi was prepared by addition of 0% (control), 1%, 2%, 3%, and 4% red pepper seed powder. The moisture and ash contents of samples increased with increased content of red pepper seed powder. In addition, the pH value, CIE $a^*$ value, and CIE $b^*$ value of uncooked and cooked samples increased with higher content of red pepper seed powder. However, cooking loss, diameter reduction, and thickness reduction of samples decreased with increasing content of red pepper seed powder. The hardness, gumminess, and chewiness of samples increased with higher content of red pepper seed powder, and the sensory evaluation of tteokgalbi containing 3% red pepper seed powder was the highest. Therefore, usages of red pepper seed powder can improve quality characteristics of tteokgalbi.

• Economic and Environmental Geology
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• v.47 no.5
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• pp.507-515
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• 2014

Asbestos is designated as carcinogen minerals. Detoxification of asbestos is being conducted by physical and chemical treatments that lead the formation of non-fibrous mineral particles or phase transitions. Major researches have been performed on mineralogical properties of asbestos and possibilities of detoxification in Korea. More specific studies are needed to prove the form and crystal structure changes during the detoxification of asbestos via heat treatment. Therefore, we studied thermal effects on mineralogical characteristics of chrysotile and asbestiform tremolite using electron microscopy investigation. Electron microscopy investigation showed chrysotile fibers were fully transformed into rod-shaped forsterite at $850^{\circ}C$ in 2 hours, and asbestiform tremolite fibers were converted into non-fibrous diopside at $1050^{\circ}C$ in 2 hours. Fibrous asbestos were converted into rod-shaped minerals, which are non-asbestiform. However, compositions of both minerals were not changed before and after heat treatment. These results indicate that thermal treatment of asbestos completely broke down asbestos structure due to dehydroxylation and recrystallization. Thus, electron microscopy investigation can provide the useful information of shapes, crystal structure, and chemistries of the asbestos for the detoxification.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.05a
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• pp.58-61
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• 1995

Instead of using CCl$_4$CCl$_2$F$_2$ gases, we used a alternative reaction gas of CFCs which we have developed, for the experiment of laser induced dry etching of laser induced dry etching of GaAs, and compared with the etch profile of a usual reation gas. Laser powers(power density) on the sample surface were varied from 100 mW(12.7 MW/$\textrm{cm}^2$) to 210mW(27 MW/$\textrm{cm}^2$) The laser beam was scanned over the sample by moving the cell with a speed raging from 8.3$\mu\textrm{m}$/sec and the gas pressure also was varied form 260 Torr to 760 Torr, High etching rates up to 136 $\mu\textrm{m}$/sec and an aspect ratio of 2.6 have been achieved by single scan of laser beam. The chemical compositions of the reaction products deposited on the etched groove were measured by Auger electron spectroscopy(AES) Etch profiles, including depth and width were observed by scanning electron microscopy(SEM)

• Journal of Life Science
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• v.18 no.8
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• pp.1140-1146
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• 2008

In order to improve the functional properties of kochujang, garic porridge was added to traditional kochujang during manufacturing. Changes in physiochemical properties of kochujang by garic porridge addition were then investigated. No big differences in general chemical compositions was observed between three kinds of kochujangs tested in this study, general kochujang purchased from a market (GK), kochujang added with raw garlic (RGK) and kochujang added with garlic porridge (GPK). However, GPK showed higher level of antioxidant and anticancer activities than those of others. The methanolic extract of GPK showed 66.38% of DPPH radical scavenging activity, while the extracts of GK and RGK exhibited 38.44% and 50.97%, respectively. Also, the effects of three different extracts of kochujangs on cell proliferation of stomach cancer cell (MKN 45), colon cancer cell (HCT116), and lung cancer cell (NCI-H460) were investigated using MTT assay. All of three extracts exhibited the highest anti-proliferative activity against stomach cancer cell, even though the proliferation of colon cancer cell and lung cancer cell were also inhibited. Among them, the extract of GPK showed the highest anti-proliferative activity (62.35%) against stomach cancer cell. From the results obtained in the present study, we concluded that the antioxidant and anticancer activity of GPK mainly originated from garlic because GPK was consisted of 23% garlic (w/w) compared to 10% (w/w) of RGK.