• Transactions of the Korean hydrogen and new energy society
• /
• v.7 no.1
• /
• pp.81-92
• /
• 1996

The Ar/Ar-$H_2$ plasma method was applied to reduce oxides and refine metals of V, Ta and B. In addition, the high temperature chemical reaction in Ar plasma and of the refining reaction in the Ar-(20%)$H_2$ plasma were analyzed. The crude V of 96wt% purity was obtained at the ratio of $C/V_{2}O_{5}=4.50$ by the Ar plasma reduction grade and the maximum reduction was obtained at $C/V_{2}O_{5}=4.50$ due to the $O_{2}$ loss from the thermal decomposition of vanadium oxide. In the Ar-(20%)$H_2$ plasma refining, the metallic V of 99.2wt% was produced at the ratio of $C/V_{2}O_{5}=4.40$. It was considered that a main refining reaction resulted from the chemical reaction between the residual carbon and residual oxygen. The metallic Ta of 99.8wt% was obtained at the ratio of $C/Ta_{2}O_{5}=5.10$ in a Ar plasma reduction and the Oz loss from the thermal decomposition of tantalum pentoxide did not take place. The deoxidation reaction was more significant than the decarburization reaction in the Ar-(20%)$H_2$ plasma refining and the metallic Ta of 99.9wt% was produced within the range of $C/Ta_{2}O_{5}$ ratio of 4.50 to 5.10. The Vickers hardness of Ta in the above mentioned range was about 220Hv due to the decrease in a residual oxygen by the deoxidation reaction. On the other hand, C is no suitable agent for the reduction of $B_{2}O_{3}$ by the Ar and Ar-$H_2$ plasma. But Fe-B-Si alloy was produced with the reduction of $B_{2}O_{3}$ in the melt when Fe, C, $B_{2}O_{3}$, and ferroboron mixtures were melted by the high frequency induction melting.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.44 no.3
• /
• pp.211-218
• /
• 2018

Instant face lifting cosmetics contain various film forming agents for stretching the wrinkles on the skin surface. But, most of the film-forming polymers have sticky feels. And they are easily scrubbed out when skin is rubbed on. In this study, we focused on the influence of sodium silicate that has rapid film forming effect on skin surface and immediate wrinkle reducing effect. Sodium silicate, also known as water glass or soluble glass, is a compound containing sodium oxide and silica. Sodium silicate is a white powder that is readily soluble in water, producing an alkaline solution. Sodium silicate is stable in neutral and alkaline solutions. The sodium silicate solution hardens by drying in air and rapidly forms a thin film. When the solution is applied to the skin, the fine membrane coating is formed by water evaporation and ionic bond re-formation. It also makes the strong siloxane (Si-O) bonding on the skin surface. When these fixation properties are applied to cosmetics, they can give remarkable skin tightening effect. The sodium silicate solution can provide the lifting effect by forming a film on skin at a proper concentration. But, skin irritation may be caused with too high concentration of sodium silicate. We studied a desirable range of the sodium silicate concentration and combination with other fixatives for skin care formulation that has no sticky feels and no scrubbing out phenomenon. Immediate lifting gel was developed by using sodium silicate and various thickening systems. Among of the various thickeners, aluminum magnesium silicate showed the best compatibility with sodium silicate for rapid lifting effect. This instant physical lifting gel was confirmed as a low stimulating formula by skin clinical test.

• The Journal of the Petrological Society of Korea
• /
• v.15 no.4 s.46
• /
• pp.167-179
• /
• 2006

Division of granites in the Galmal-Yeonbug area, northern Gyeonggi, can be grey hornblende biotite granite (JHBG), biotite granite (JBG) and pink hornblende biotite granite (CHBG) by lithofacies. JHBG of small stock occurs as medium-grained with grey color and minute sphene. JBG occurs as medium-grained and light grey to grey in the north-east part of the area. The main study target CHBG covers in the north-southeast part of the area, and occurs medium-to coarse-grained with pink color. CHBG shows partly minute miaroles, and pegmatitic pocket with druse texture. From the mineral age data (K-Ar method). JHBG and JBG and CHBG are the igneous activity products of Daebo orogeny with different Jurassic and Bulgugsa disturbance of Cretaceous, respectively. And the age data also agree with geologic occurrences and interpretations of the granites in the field. CHBG consists of quartz, plagioclase, alkali-feldspar, biotite, hornblende, allanite, apatite, zircon, some calcite and opaques. Among them, alkalifeldspar and calcite occur characteristically in mostly perthitic othoclase and secondary filling of minutely miarolitic cavity, respectively. In modal analysis and QAP diagram, CHBG plots in granite field, and especially boundary of monzo-and syeno-granite fields. From the major oxide variations, molar A/CNK, $SiO_{2}\;vs\;K_{2}O$, AMF and so on, CHBG belongs to the acidic, peraluminous and high-K calc-alkaline, and was late differentiation product of single granitic magma. Barium and strontium have also dominantly differentiation trend, and in CaO vs Sr and $K_{2}O$ vs Sr, Sr was more participitated in the fractionation of plagioclase than that of alkali-feldspar. Normalized REE concentrations to chondrite value have parallel and gradual LREE enrichment and HREE depletion patterns, and weak Eu negative anomalies and narrow ranges of normalized Eu can suggest that plagioclase fractionations occurred mildly in the whole CHBG.

• Korean Journal of Soil Science and Fertilizer
• /
• v.40 no.5
• /
• pp.418-428
• /
• 2007

Physical and chemical properties of the aggregate by-products including sludge and crushed dust samples collected from the 21 private companies throughout the country were analyzed to evaluate possible usage of the by-products as artificial soil materials for plantation. The pH of the materials ranged from 8.0 to 11.0. The organic matter content was $2.85g\;kg^{-1}$, and the total nitrogen content and available phosphate content were low as 0.7 percents and $12.98mg\;kg^{-1}$, respectively. Exchangeable $Ca^{2+}$, $Mg^{2+}$, $K^+$, and $Na^+$ were 2.29, 0.47, 0.02 and $0.05cmol\;kg^{-1}$, respectively. Heavy metal contents were lower than the limits regulated by environmental law of Korea. Textural analysis showed that most of the materials were silt loam with low water holding capacity ranged from 0.67 to 7.41 percents, and with low hydraulic conductivity ranged from 0.4 to $2.8m\;s^{-1}$. Mineralogical analysis showed that the aggregate by product materials were mostly composed of silicate, alumina and ferric oxides except calcium oxide dominant materials derived from limestones. The primary minerals were quartz, feldspars and dolomites derived from granite and granitic gneiss materials. Some samples derived from limestone material showed calcite and graphite together with the above minerals. According to the result, it can be concluded that the materials could be used as the artificial soil material for plantation after proper improvement of the physico-chemical properties and fertility.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.3
• /
• pp.356-362
• /
• 2015

Prickly pear cactus cladodes were extracted with hot water and 70% ethanol, followed by fractionation with n-hexane (HF), ethyl acetate (EF), n-butanol (BF), and distilled water. Total phenolics and total flavonoid contents as well as antioxidative and anti-inflammatory activities were then measured. Total phenolic contents were 784, 452, and 220 mg gallic acid equivalents (GAE)/g, whereas total flavonoid contents were 214, 76, and 113 mg quercetin equivalents (QE)/g in EF, BF, and HF, respectively. DPPH and ABTS radical scavenging activities ($IC_{50}$) were 103 and $105{\mu}g/mL$ in EF, 359 and $379{\mu}g/mL$ in BF, and 469 and $605{\mu}g/mL$ in HF, respectively. Oxygen radical absorbance capacity was highest at $391{\mu}M$ TE in EF (in decreasing order of $117{\mu}M$ TE in BF and $64{\mu}M$ TE in HF), whereas superoxide anion radical scavenging activity ($IC_{50}$) was highest at $40{\mu}g/mL$ in EF (in decreasing order of $69{\mu}g/mL$ in BF and $98{\mu}g/mL$ in 70% ethanol extract). Inhibitory activity ($IC_{50}$) of nitric oxide (NO) production induced by LPS-activated RAW264.7 cells was highest at $62{\mu}g/mL$ in HF (in decreasing order of $104{\mu}g/mL$ in EF and $465{\mu}g/mL$ in BF). The selectivity index (ratio of inhibitory activity of NO production to cell cytotoxicity) was highest at 4.63 in EF (in decreasing order of 3.37 in HF and 2.14 in BF). In conclusion, EF showed potent antioxidant and anti-inflammatory effects with high phenolic and flavonoid contents.

• Korean Journal of Food Science and Technology
• /
• v.46 no.6
• /
• pp.729-733
• /
• 2014

Laminaria japonica roots have not been used practically in Korea. In this study, in order to promote the use of these by-products, the anti-inflammatory activity of an ethanol extract of Laminaria japonica root (LJREE) was investigated using a lipopolysaccharide (LPS) to induce an inflammatory response in RAW 264.7 cells. To examine the potential anti-inflammatory effects of LJREE, levels of nitric oxide (NO) and pro-inflammatory cytokines, such as interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and interleukin-$1{\beta}$ (IL-$1{\beta}$), and cell proliferation were measured. We found that NO levels decreased in a dose-dependent manner, the production of IL-6, TNF-${\alpha}$, and IL-$1{\beta}$ was suppressed, and the production of IL-$1{\beta}$ was inhibited over 30% after treatment with $100{\mu}g/mL$ LJREE. In conclusion, the proliferation of RAW 264.7 cells, measured by MTT assay, confirmed that LJREE may have significant effects on inflammatory factors without any cytotoxicity, making it a potential anti-inflammatory agent.

• Nuclear Engineering and Technology
• /
• v.39 no.5
• /
• pp.603-616
• /
• 2007

Roy Huddle, having invented the coated particle in Harwell 1957, stated in the early 1970s that we know now everything about particles and coatings and should be going over to deal with other problems. This was on the occasion of the Dragon fuel performance information meeting London 1973: How wrong a genius be! It took until 1978 that really good particles were made in Germany, then during the Japanese HTTR production in the 1990s and finally the Chinese 2000-2001 campaign for HTR-10. Here, we present a review of history and present status. Today, good fuel is measured by different standards from the seventies: where $9*10^{-4}$ initial free heavy metal fraction was typical for early AVR carbide fuel and $3*10^{-4}$ initial free heavy metal fraction was acceptable for oxide fuel in THTR, we insist on values more than an order of magnitude below this value today. Half a percent of particle failure at the end-of-irradiation, another ancient standard, is not even acceptable today, even for the most severe accidents. While legislation and licensing has not changed, one of the reasons we insist on these improvements is the preference for passive systems rather than active controls of earlier times. After renewed HTGR interest, we are reporting about the start of new or reactivated coated particle work in several parts of the world, considering the aspects of designs/ traditional and new materials, manufacturing technologies/ quality control quality assurance, irradiation and accident performance, modeling and performance predictions, and fuel cycle aspects and spent fuel treatment. In very general terms, the coated particle should be strong, reliable, retentive, and affordable. These properties have to be quantified and will be eventually optimized for a specific application system. Results obtained so far indicate that the same particle can be used for steam cycle applications with $700-750^{\circ}C$ helium coolant gas exit, for gas turbine applications at $850-900^{\circ}C$ and for process heat/hydrogen generation applications with $950^{\circ}C$ outlet temperatures. There is a clear set of standards for modem high quality fuel in terms of low levels of heavy metal contamination, manufacture-induced particle defects during fuel body and fuel element making, irradiation/accident induced particle failures and limits on fission product release from intact particles. While gas-cooled reactor design is still open-ended with blocks for the prismatic and spherical fuel elements for the pebble-bed design, there is near worldwide agreement on high quality fuel: a $500{\mu}m$ diameter $UO_2$ kernel of 10% enrichment is surrounded by a $100{\mu}m$ thick sacrificial buffer layer to be followed by a dense inner pyrocarbon layer, a high quality silicon carbide layer of $35{\mu}m$ thickness and theoretical density and another outer pyrocarbon layer. Good performance has been demonstrated both under operational and under accident conditions, i.e. to 10% FIMA and maximum $1600^{\circ}C$ afterwards. And it is the wide-ranging demonstration experience that makes this particle superior. Recommendations are made for further work: 1. Generation of data for presently manufactured materials, e.g. SiC strength and strength distribution, PyC creep and shrinkage and many more material data sets. 2. Renewed start of irradiation and accident testing of modem coated particle fuel. 3. Analysis of existing and newly created data with a view to demonstrate satisfactory performance at burnups beyond 10% FIMA and complete fission product retention even in accidents that go beyond $1600^{\circ}C$ for a short period of time. This work should proceed at both national and international level.

• Journal of Food Hygiene and Safety
• /
• v.32 no.6
• /
• pp.513-520
• /
• 2017

This study was performed to provide basic data of 'Kangilok'. The objective of this study was to investigate worth of 4 parts of maize hybrid for grain, 'Kangilok' for functional foods. The 4 parts are kernels, dehulled kernels, skin of kernels and cobs of 'Kangilok'. We evaluated moisture, crude ash, crude lipid, crude protein, crude fiber and mineral content of 'Kangilok'. The moisture of kernels, dehulled kernels, skin of kernels and cobs of 'Kangilok' were 11.27%, 12.40%, 9.45%, 8.85% and the crude ash were 1.26%, 0.73%, 3.19%, 1.42%. Each of the crude lipid were 3.84%, 2.69%, 8.59%, 0.46% and the crude protein were 9.40%, 9.96%, 12.10%, 2.80%. The crude fiber of kernels, dehulled kernels, skin of kernels and cobs of 'Kangilok' were 2.24%, 0.92%, 7.07%, and 33.51%. Among the mineral contents, Ca and K content of cobs were highest by 4.84 mg/100 g, 114.33 mg/100 g and Fe, Mn contents of skin of kernels were highest by 5.30 mg/100 g, 2.64 mg/100 g. Mg content of kernels was the highest by 27.42 mg/100 g. P content of kernels, dehulled kernels, skin of kernels and cobs were 1.20%, 0.96%, 2.41%, and 0.19%. It was performed test on anti-oxidative, anti-inflammatory activities of 60% ethanol extract from 4 parts of Kangilok. The anti-oxidative effect was measured by DPPH and ABTS radical scavenging activity. As a results, DPPH radical scavenging activity (10 mg/mL) was 72.59%~93.05% and ABTS radical scavenging activity (10 mg/mL) was 48.17%~79.88%. The anti-inflammatory effect was measured by ability to inhibit production nitric oxide (NO) in RAW264.7 cell. As a result, all the extract of 4 parts were showed significantly inhibitory effect on NO production. Carotenoid contents quantified by using HPLC. ${\beta}$-Carotene of carotenoid was not analyzed in all the sample. Lutein and zeaxantin ware analyzed in kernels and skin of kernels.

• Food Science and Preservation
• /
• v.14 no.2
• /
• pp.220-225
• /
• 2007

This study was performed to measure the antioxidative, antimutagenic, and cytotoxic properties of Prunus armeniaca using the DPPH (1, 1-diphenyl-2-picrylhydrazyl) free radical donating method, the Ames test, and cytotoxicity measurements, respectively. Electron-donating abilities were 48.3, 43.9, 14.8 and 12.9 per g dry matter of P. armeniaca seed (PAS), P. armeniaca flesh(PAF), butylated hydroxytoluene, and ${\alpha}-tocopherol$, respectively. The direct antimutagenic effects of an ethanol extract of P. armeniaca were examined in Ames tests using Salmonella typhimurium TA98 and TA100 as reporter organisms. In the Ames test, the ethanol extract of P. armenicaca alone did not exhibit any mutagenicity but the extract did show substantial inhibitory effects against mutations induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) and 4-nitroquinoline-1-oxide(4NQO). The ethanol extract of PAS(200g dry matter/plate) inhibited strain TA98 mutagenesis induced by 4NQO by ca. 37.9%, and mutation inhibition values of 42.1% and 69.4%, respectively, were observed when 4NQO and MNNG acted on the TA100 strain. The cytotoxic effects of ethanol extracts of P. armeniaca against cell lines of human lung carcinoma(A549), human breast adenocarcinoma(MCF-7), human hepatocellular carcinoma(Hep3B), human cervical adenocarcinoma(HeLa), and human gastric carcinoma(AGS) rose with increases in extract concentration. An ethanol extract(4mg/mL dry matter) of PAF showed strong cytotoxicities of 88.2%, 58%, 72.8%, 89.4%, and 91.9% against A549, AGS, MCF-7, HeLa, and Hep3B cells, respectively. In contrast, the same extract showed only 13 37% cytotoxicity for a nomal human kiney cell line(293). It is suggested that P. armeniaca possesses useful antioxidative, antimutagenic, and anticancer properties.