• Korean journal of food and cookery science
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• v.17 no.5
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• pp.478-482
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• 2001

This experiment was carried out to clarify the effect of frying temperature and gelatinization method on the quality of popped rice for Salyeotgangjung. Frying at 220$^{\circ}C$ or 230$^{\circ}C$ gave a good expansion and score of sensory evaluation. But the frying oil began to smoke at 230$^{\circ}C$. There was no significant difference in the quality of popped rices between the treatments of minimum gelatinization after washing rice and moderate gelatinization after soaking for 80 minutes at 30$^{\circ}C$. In conclusion, frying washed rice with minimum gelatinization at 220$^{\circ}C$ would be considered as the best method for making Salyeotganagjung.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.6
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• pp.88-95
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• 2013

Effects of beating and water immersion time on fiber swelling and paper properties were elucidated for the fundamental study of producing high bulk paper. Chemical pulps were beaten for various freeness and the beaten pulp was immersed in water up to 24 hours. Fiber swelling was evaluated by measuring water retention value (WRV). It was found that fiber swelling, bulk and paper strength were quickly changed at the initial stage of beating. Immersion in water did not significantly increase WRV, paper density and strength, implying that soaking in water alone could not effectively swell fiber wall. In order to swell further, hydrogen bonds between fibrils in fiber wall and hence fiber wall structure shall be broken by mechanical force during beating.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.265.1-265.1
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• 2013

Nanoporous anodic aluminum oxide (AAO), a self-ordered hexagonal array has various applications for nanofabrication such as nanotemplate, and nanostructure. In order to obtain highly-ordered porous alumina membranes, Masuda et al. proposed a two-step anodization process however this process is confined to small domain size and long hours. Recently, alternative methods overcoming limitations of two-step process were used to make prepatterned Al surface. In this work, we confirmed that there is a specific tendency used a PDMS stamp to obtain a pre-patterned Al surface. Using the nanoindentaions of a PDMS stamp as chemical carrier for wet etching, we can easily get ordered nanoporous template without two-step process. This chemical etching method using a PDMS stamp is very simple, fast and inexpensive. We use two types of PDMS stamps that have different intervals (800nm, 1200nm) and change some parameters have influenced the patterning of being anodized, applied voltage, soaking and stamping time. Through these factors, we demonstrated the patterning effect of large scale PDMS stamp.

• The Korean Journal of Mycology
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• v.21 no.4
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• pp.316-322
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• 1993

Examination by scanning electron microscopy and potato-dextrose agar medium showed that the dry seeds of R. raetam were externally free of fungi. When planted in sandy loam soil, the seeds become colonized with eleven soilborne fungal species. The fungi were isolated on cellulose agar, pectin agar and lignin agar media. Aspergillus flavus, A. niger, Penicillium capsulatum and Fusarium oxysporum had broad occurrence and recovered on the three media. The production of hydrolytic enzymes by the isolated fungi depends on the substrate and species. P. capsulatum, P. spinulosum and A. niger had wide enzymatic amplitude and they were able to produce cellulolytic, pectolytic and lignolytic activities on corresponding substrates as well as on seed coat containing media. The lignolytic activities of the isolated species except Chaetomium bostrychods and Trichoderma viride were enhanced on applying the seed coat materials as C-source rather than using lignin. Soaking R. raetam seeds in culture filtrates of the most fungi grown on seed coat supplemented media induced pronounced and distinct stimulating effect on seed germination. The most effective filtrates were those of P. capsulatum, P. spinulosum and Sporotrichum pulverulentum.

• Journal of the Korean Ceramic Society
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• v.19 no.2
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• pp.127-132
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• 1982

This experiment has been carried out for the purpose of investigating the effect of additives on densification and grain growth in magnesium oxide by a two-step process; hot pressing and heat treating. MgO powder has been obtained by calcining extra reagent grade MgCO3 at 90$0^{\circ}C$ for 30 minutes, and additives have been added to $MgCO_3$ in the form of soluble salts-Al$(NO_3)_3$$. $9H_2O$ and $Cr(NO_3)_3$.9H_2O$. The hot pressing has been carried out with changes of soaking time at 125$0^{\circ}C$ under the pressure of 250kg/$\textrm{cm}^2$, and the heat treating also at same temperature. The initial particle size of MgO measured by particle size analyzer was 0.86 microns. Densification rate obeyed the equation D=K lnt + C, and grain growth rate obeyed the equation G-G0=kt1/2. It was vaporization of some $Cr_2O_3$ and formation of solid solution that had an influence on desification of MgO containing $Cr_2O_3$. Activation energy for grain growth of pure MgO was 62.4 kcal/mole, therefore grain growth was supposed to be diffusioncontrolled process. But after heat treatmeat, excess additives were expected to slow down the grain growth by the formation of second phase or the solute atoms at grainboundary.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.11a
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• pp.43-48
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• 2003

This paper investigate that the effect of the concrete containing mineral admixtures(pozzolanic materials such as fly-ash, ground granulated blast-furnace slag, silica fume and meta kaolin) on the resistance properties to chloride ion invasion. The purposed testing procedure was applied to the concrete added mineral admixtures for 3~4 replacement ratios under W/B ratios ranged from 0.40 to 0.55. For the electrical migration test, Tang and Nilsson's method was used to estimate the migration coefficient of chloride ion. As a results, the W/B ratios, kinds of admixture and replacement ratios, water curing periods had a great effect on the migration coefficient of chloride ion, and the optimal replacement ratios of admixture had a limitation for each admixtures. Also, the addition of mineral admixtures by mass(replacement of OPC) enhanced the resistance of the mixture to chloride penetration compared with the plain concrete. The amount of acid soluble chloride ions and water soluble chloride ions were varied with the kinds of mineral admixtures. The compressive strength was shown related to the migration coefficient of chloride ion, the compressive strength increased with the decreasing migration coefficient of chloride ion. Below the 50MPa, the variation of migration coefficient of concrete added mineral admixtures was bigger than plain concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.43-48
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• 2003

This paper investigate that the effect of the concrete containing mineral admixtures(pozzaolanic materials such as fly-ash, ground granulated blast-furnace slag, silica fume and meta kaolin) on the resistance properties to chloride ion invasion. The purposed testing procedure was applied to the concrete added mineral admixtures for 3∼4 replacement ratios under W/B ratios ranged from 0.40 to 0.55. For the electrical migration test, Tang and Nilsson's method was used to estimate the migration coefficient of chloride ion. As a results, the W/B ratios, kinds of admixture and replacement ratios, water curing periods had a great effect on the migration coefficient of chloride ion, and the optimal replacement ratios of admixture had a limitation for each admixtures. Also, the addition of mineral admixtures by mass(replacement of OPC) enhanced the resistance of the mixture to chloride penetration compared with the plain concrete. The amount of acid soluble chloride ions and water soluble chloride ions were varied with the kinds of mineral admixtures. The compressive strength was shown related to the migration coefficient of chloride ion, the compressive strength increased with the decreasing migration coefficient of chloride ion. Below the 50MPa, the variation of migration coefficient of concrete added mineral admixtures was bigger than plain concrete.

• Corrosion Science and Technology
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• v.9 no.6
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• pp.247-253
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• 2010

The characteristics of selective oxidation prior to hot-dip galvanizing with the annealing atmosphere dew point and chemical composition in dual-phase steels and their effect on the inhibition layer formation relevant to coating adhesion have been studied using a combination of electron microscopic and surface analytical techniques. The annealed and also galvanized samples of 3 kinds of Si/Mn ratios with varied amounts of Si addition were prepared by galvanizing simulator. The dew point was controlled at soaking temperature $800^{\circ}C$ in 15%$H_2$ -85%$N_2$ atmosphere. It was shown that good adhesion factors were mainly uniformity of oxide particle distribution of low number density and low Si/Mn ratio prior to hot-dip galvanizing. Their effect was the greatly reduced coating bare spots and the formation of uniform inhibition layer leading to good adhesion of Zn overlay. The mechanism of good adhesion is suggested by two processes: the formation of inhibition layer on the oxide free surface uncovered with no $SiO_2$-containing particles in particular, and the inhibition layer bridging of oxide particles. The growth of inhibition layer was enhanced markedly by the delayed reaction of Fe and Al with the increase of Si/Mn ratio.

• Journal of Pharmaceutical Investigation
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• v.34 no.4
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• pp.275-281
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• 2004

We have studied the effect of polarity, current density, current duration, crosslinking density, swelling ratio, and permeation enhancers on the transdermal flux of ketoprofen from acrylamide hydrogel. Hydrogel was prepared by free radical crosslinking polymerization of acrylamide. Drug loading was made just before transport experiment by soaking the hydrogel in solution containing drug. In vitro flux study using hairless mouse skin was performed at $36.5^{\circ}C$ using side-by-side diffusion cell, and the drug was analysed using HPLC/UV system. The result showed that, compared to passive flux, the total amount of drug transported increased about 18 folds by the application of $0.4\;mA/cm^2$ cathodal current. Anodal delivery with same current density also increased the total amount of drug transported about 13 folds. It seemed that the increase in flux was due to the electrorepulsion and the increase in passive permeability of the skin by the current application. Flux increased as current density, the duration of current application and loading amount (swelling duration) increased. As the cross linking density of the hydrogel increased, flux clearly decreased. The effect of hydrophilic enhancers (urea, N-methyl pyrrolidone, Tween 20) and some hydrophobic enhancers (propylene glycol monolaurate and isopropyl myristate) was minimal. However, about 3 folds increase in flux was observed when 5% oleic acid was used. Overall, these results provide some useful information on the design of an optimized iontophoretic delivery system of ketoprofen.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.415-420
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• 2017

Soybean sprouts are the third-most consumed vegetable in Korea. Several studies on cultivation techniques, including use of medicinal plants extracts, have been performed to enhance the quality and yield of soybean sprouts. The objective of the present study was to investigate the effect of lacquer, a medicinal plant extract, on the yield and nutritional value of soybean sprouts. Linolenic acid content was significantly (p<0.05) increased in the sprouts produced by soaking seeds in lacquer extract diluted with equal volume of water. Lacquer extract significantly increased the flavonoid and phenolic contents (p<0.05). The content of total free amino acids, including ${\gamma}$-aminobutyric acid, was higher in lacquer extract-treated sprouts than in the untreated control. Results of this study suggest that lacquer extract could be used for enhancing the yield and nutritional values of soybean sprouts.