• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1278-1284
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• 2003

This study was carried out to investigate the optimum conditions for making “sponge cake” with addition of ingredient, laver powder, and the quality characteristics of a new sponge cake. The moisture contents of sponge cake with 2, 4, 6% laver powder did not change but with 8 and 10%, the moisture contents increased to 28.89% and 30.69%, respectively. While specific gravity increased to 0.674 (control 0.493) when 10% laver powder was added, but volume was decreased. Most abundant mineral was Ca, followed by Na, Fe, Mn, Cu and Zn. The crust color degree of sponge cake with laver powder showed low marks on L, a, b. The crumb color degree showed low marks on L, b while “a” degree redness indicated highest marks with 4% laver powder. When it was seen under the microscope, the air cell numbers were decreased but the cell size became bigger. More free amino acid was contained when the laver powder was added. L-glutamic acid, L-alanine, L-aspartic acid and L-leucine were the major free amino acids. Hardness, springiness, cohesiveness, gumminess, chewiness and resilience degree of sponge cake with addition of laver power were higher than those of control. The sensory evaluation indicated that addition of 2% laver powder enhanced most mouth feeling, appearance, hardness, moistness, flavor and overall acceptability.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.363-370
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• 2016

Lightweight geopolymers are more readily produced and give higher fire resistant performance than foam cement concrete. Lowering the density of solid geopolymers can be achieved by inducing chemical reactions that entrain gases to foam the geopolymer structure. This paper reports on the effects of adding different concentrations of aluminum powder on the properties of cellular structured geopolymers. The apparent density of lightweight geopolymers has a range from 0.7 to $1.2g/m^3$ with 0.025, 0.05 and 0.10 wt% of a foaming agent concentration, which corresponds to about 37~60 % of the apparent density, $1.96g/cm^3$, of solid geopolymers. The compressive strength of cellular structured geopolymers decreased to 6~18 % of the compressive strength, 45 MPa of solid geopolymers. The microstructure of geopolymers gel was equivalent for both solid and cellular structured geopolymers. The workability of geopolymers with polyprophylene fibers needs to be improved as in fiber-reinforced cement concrete. The lightweight geopolymers could be used as indoor wall tile or board due to fire resistance and incombustibility of geopolymers.

• Journal of the Korea Concrete Institute
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• v.25 no.2
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• pp.209-215
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• 2013

This study is aimed to identify the method to use the CaO-$Al_2O_3$ system of rapidly cooled steel making slag (RCSS) as the environment-friendly inorganic accelerating agent by analyzing its physical and chemical properties. The fraction of rapidly cooled steel making slag is distinguished from its fibrous, and the contents of CaO and $Fe_2O_3$ are inversely proportional across different fractions. In addition, as the content of CaO decreased and the content of $Fe_2O_3$ increased, the loss ignition tended to become negative (-) and the density increased. The pore distribution by mercury intrusion porosimetry is very low as compared to the slowly cooled steel-making slag, which indicates that the internal defect and the microspore rate are remarkably lowered by the rapid cooling. To analyze the major minerals the rapidly cooled steel-making slag, XRD, f-CaO quantification and SEM-EDAX analysis have been performed. The results shows that f-CaO does not exist, and the components are mainly consisted of $C_{12}A_7$ and reactive ${\beta}-C_2S$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.477-480
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• 2002

Si-O-C(-H) thin film with a tow dielectric constant were deposited on a P-type Si(100) substrate by an inductively coupled plasma chemical vapor deposition (ICPCVD). Bis-trimethylsilymethane (BTMSM, H$_{9}$C$_3$-Si-CH$_2$-Si-C$_3$H$_{9}$) and oxygen gas were used as Precursor. Hybrid type Si-O-C(-H) thin films with organic material have been generated many voids after annealing. Consequently, the Si-O-C(-H) films can be made a low dielectric material by the effect of void. The surface characterization of Si-O-C(-H) thin films were performed by SEM(scanning electron microscope). The characteristic analysis of Si-O-C(-H) thin films were performed by X-ray photoelectron spectroscopy (XPS).

• Korean Chemical Engineering Research
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• v.51 no.5
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• pp.550-555
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• 2013

A hydrogel electrolyte consisting of potassium poly(acrylate) (PAAK) (3 wt%) in 6 M KOH aqueous solution is coated on poly(acrylonitrile) nonwoven separator to examine high-rate characteristics of activated carbon supercapacitor adopting the separator. The hydrogel is homogeneously coated on the surface pores of the nonwoven separator. The electrolyte uptake of the PAAK hydrogel maintains for 24 days higher than 230% and the coated separator shows slightly lower ionic conductivity ($2.9{\times}10^{-2}Scm^{-1}$) than that ($3.6{\times}10^{-2}Scm^{-1}$) of using 6 M KOH only. The activated carbon supercapacitor adopting the coated separator shows a specific capacitance higher than $27Fg^{-1}$ at $1000mVs^{-1}$ and a retention ratio higher than 97% after the 1000th cycle. This is due to strong interfacial contact of coated hydrogel electrolyte between the activated carbon electrode and the nonwoven separator.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.311-319
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• 2011

Overusing chemical fertilizers involves potassium accumulation in the soil, which can become a toxicity problem in agriculture. This study was conducted to investigate the effect of potassium (K) treatment on growth, physiological characteristics, and morphological changes using Chinese cabbage (Brassica rapa L. ssp. campestris). With high (600 mM) K treatment, the plant growth traits of leaf length, leaf area, and fresh and dry weight of shoots and roots decreased, whereas chlorophyll content increased. As the concentration of K increasing, total N, P, and K increased in leaves, but concentrations of Ca, Mg, and Na decreased. However, Mn, Fe and Zn contents were highest in 100 mM K treatment. Chlorophyll a, b, and carotenoids increased with increasing K concentration. Maximum photochemical efficiency ($F_v/F_m$) was not significant in the all treatments, whereas $CO_2$ assimilation decreased with increasing K level due to stomatal degradation. Total free amino acids increased with the 10 and 100 mM K but decreased at 600 mM K treatments. Therefore, the growth and physiological characteristics of Chinese cabbage ascertained that tolerance up to 100 mM K when grown with nutrient solution in pot culture.

• Culinary science and hospitality research
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• v.16 no.4
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• pp.260-273
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• 2010

This study aims to examine the quality characteristics of bread by the amount of addition of black garlic powder. there bas been increasingly higher interest in functional foods. According to the results, after analyzing mixograph, of the dough by using mixograph, the bread containing black garlic powder was considered to be most suitable for making bread As for stickiness of the dough with black garlic powder added, the higher black garlic powder was added, the more the bread becomes sticky. BG 6(i.e. bread with 6% of black garlic powder) had the highest fermentation rate for 60-minute fermentation period(i.e. first fermentation). Analysis through crumbScan showed that there were significant differences in crumb fineness between the control and bread with addition of black garlic powder, showing no significant difference by the amount of addition of black garlic powder. As for the volume and specific volume of bread with addition of black garlic powder, the more black garlic powder, the less volume and specific volume. Preference test showed that BG 6 got the best appearance and taste, in overall preference, BG 6 and BG 9(i.e. bread with 9% of black garlic powder) showed the same degree. However, BG 6 is considered the optimum addition of black garlic powder to reduce the production costs in the numerical respect.

• Polymer(Korea)
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• v.38 no.6
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• pp.760-766
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• 2014

Bead type super-absorbent resins to be used for release-control were prepared by modification of the inverse suspension polymerization, and their physical properties were characterized. Acrylic acid and acrylamide were used as monomers, and N,N-methylenebisacrylamide was used as crosslinker, controlling the viscosity of monomer solution by adding hydroxyethylcellulose (HEC). SEM studies of the synthesized beads verified that the bead surfaces had many pores with their diameters of several tens nm. The bead sizes were in the range of $500{\sim}3000{\mu}m$, depending on the viscosity of the monomer solution. Both absorbent amount and absorbent rate of the beads were inversely proportional to the bead size, and the maximum water absorbent amount of 1 g beads was determined to be ca. 170~200 g for 5 hrs. The absorbent rate was also dependent on pH change of the aqueous solution, exhibiting the maximum rate in pH ranging from 5 to 11. The absorbent rate decreased as the concentration of salt (NaCl and $MgCl_2$) or ethanol and ethylene glycol increased. Release time of the water absorbed into the bead resins was 700 hrs, confirming the usefulness of the resin for the good release-control materials.

• Food Science and Preservation
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• v.15 no.1
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• pp.37-42
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• 2008

This study investigated the effects of green tea powder (GTP) on the quality characteristics of Yukwa during storage, to improve shelf-stability and sensory quality. The crude lipid contents of Yukwa decreased with increasing levels of GTP, but significant changes in moisture contents were not found. 'The blowhole size and expansion rate of Yukwa decreased with increases in GTP. The hardness of Yukwa samples with over 2% (w/v) GTP significantly increased, but no notable changes in hardness during storage were found. Sensory evaluation tests indicated that all sensory characteristics decreased with increasing GTP levels, but there was no significant difference in overall acceptability between Yukwa samples with 1% (w/v) GTP and control. Antioxidant activity increased as the concentration of GTP increased 'The results indicate that addition of 1% (w/v) G1P yielded optimal quality of Yukwa during storage.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.736-740
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• 2005

As an alternative of yeast, various concentrations to prepare hypo-allergenic bread (HAB). Addition of sodium bicarbonate increased $CO_2$ emission, but at higher than 2.0% caused bitter taste compared to other mixtures. Addition of sucrose significantly increased $CO_2$ emission. HABs 7 ($NaHCO_3$ 2.0g+sucrose 0.63 g) and 8 ($NaHCO_3$ 2.0g+sucrose 1.0g) showed higher grain and color scores. HAB 5 ($NaHCO_3$ 1.5g+sucrose 1.0g) and 6 ($NaHCO_3$ 1.5g+sucrose 2.0g) gave higher aroma and taste scores. HAB 5 showed significantly higher overall acceptability (p<0.05) score than others, whereas HABs 7 and 8, regardless of high external sensory qualities, showed lower overall acceptabilities than HAB 5 due to bitter taste. Prototypical HAB was obtained using wheat flour (100g) and water (62mL) incubated at $37^{\circ}C$ for 4 hr for treatment of b.p pretense (100mg) before adding sodium bicarbonate (1.5%), sucrose (1.0%), NaCl (1.0%), and citric acid (1.0%).