• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.150.1-150.1
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• 2014

Showerhead is used as a main part in the semiconductor equipment. The face plate flatness should remain constant and the cleaning performance must be gained to keep the uniformity level of etching or deposition in chemical vapor deposition process. High operating temperature or long period of thermal loading could lead the showerhead to be deformed thermally. In some case, the thermal deformation appears very sensitive to showerhead performance. This paper describes the methods for robust design using computational fluid dynamics. To reveal the influence of the post distribution on flow pattern in the showerhead cavity, numerical simulation was performed for several post distributions. The flow structure appears similar to an impinging flow near a centered baffle in showerhead cavity. We took the structure as an index to estimate diffusion path. A robust design to reduce the thermal deformation of showerhead can be achieved using post number increase without ill effect on flow. To prevent the showerhead deformation by heat loading, its face plate thickness was determined additionally using numerical simulation. The face plate has thousands of impinging holes. The design key is to keep pressure drop distribution on the showerhead face plate with the holes. This study reads the methodology to apply to a showerhead hole design. A Hagen-Poiseuille equation gives the pressure drop in a fluid flowing through such hole. The assumptions of the equation are the fluid is viscous-incompressible and the flow is laminar fully developed in a through hole. An equation can be expressed with radius R and length L related to the volume flow rate Q from the Hagen-Poiseuille equation, $Q={\pi}R4{\Delta}p/8{\mu}L$, where ${\mu}$ is the viscosity and ${\Delta}p$ is the pressure drop. In present case, each hole has steps at both the inlet and the outlet, and the fluid appears compressible. So we simplify the equation as $Q=C(R,L){\Delta}p$. A series of performance curves for a through hole with geometric parameters were obtained using two-dimensional numerical simulation. We obtained a relation between the hole diameter and hole length from the test cases to determine hole diameter at fixed hole length. A numerical simulation has been performed as a tool for enhancing showerhead robust design from flow structure. Geometric parameters for the design were post distribution and face plate thickness. The reinforced showerhead has been installed and its effective deposition profile is being shown in factory.

• Food Science of Animal Resources
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• v.28 no.2
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• pp.146-153
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• 2008

The effects of the addition of Kimchi powder at levels of 1%, 2%, and 3% (w/w) to sausage formulation on the quality characteristics of low-fat sausage were determined. The CIE L-values of low-fat sausages were lower than the control (p<0.05), and were inversely proportional to the level of Kimchi powder (p<0.05). The CIE a- and CIE b-values of sausages increased with increasing levels of Kimchi powder (p<0.05), and the pH of sausages decreased in proportion to Kimchi powder acidity. Kimchi powder was effective at retaining added water in low-fat sausages since cooking yield, emulsion stability, and viscosity with the addition of 3% Kimchi powder was similar to that of the control. The protein and ash contents of sausages were not affected by Kimchi powder addition (p>0.05), while sausages containing 3% Kimchi powder had the highest water content (p<0.05). With increasing Kimchi powder concentration, hardness, gumminess, chewiness, and sensory scores increased in low-fat sausages (p<0.05).

• Applied Chemistry for Engineering
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• v.27 no.5
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• pp.516-520
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• 2016

Concentrated liquid detergents have 2~3 times higher surfactant contents [35~45% (w/w)] compared to those of normal type detergents. In general, a single surfactant forms a lyotropic liquid crystal (LC) phase when the concentration is in the region of 30~60% (w/w). Whereas the concentrated liquid detergent at about 40% (w/w) concentration in a mixed surfactant system shows an opaque appearance of gel or LC. In order to meet consumer needs and preference for product appearance, we applied hydrotropes and various surfactants systems in concentrated liquid detergents to obtain an opaque gel-phase and also a clear transparent phase at even below zero $^{\circ}C$ temperature. The more effective hydrotropes for making concentrated liquid detergents are 1,6-hexanediol, adipic acid and dipropylene glycol (DPG) which have two hydrophilic groups in both terminated positions. In order to prepare an excellent concentrated liquid detergent, good hydrotropes alongside secondary type surfactants like LAS and SAS were used. The formation of LC phase of concentrated liquid detergents at about 40% (w/w) concentration could be prevented by the use of both hydrotropes and secondary type surfactants. The result indicate that concentrated detergents having excellent low temperature stability and controlled viscosity can be prepared.

• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.40-45
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• 2001

This study was conducted to investigate the effects of various emulsifiers on the quality of the waxy rice cake. Falling numbers of the waxy rice flour with monoglyceride, lecithin and control were not significantly different, but with sugar esther 0.5% and 1% showed higher value as 88.4 and 81 than control Initial pasting temperature of the waxy rice flour was 66.78$\^{C}$ and others were 66.45 ∼ 67.05$\^{C}$ by adding 0.5%, 1% of emulsifiers such as monoglyceride, lecithin, sugar esther. Waxy rice flour with 1% sugar ester showed the highest peak viscosity as like as falling number. Waxy rice cake wish various emulsifiers showed tendency to be slowly firming rate as compared with control. In all case, waxy rice flour with sugar ester 1% was considered to be more effective to the decrease of firming rate. Waxy rice flour with lecithin showed worse visual color than others and sugar ester provided best visual and sensory quality. After 5 days cold storage, waxy rice flour with sugar ester 1%\`s Aw was 0.875 and control\`s 0.911. These results suggested that water holding capacity of sugar ester was the best during storage.

• Food Science of Animal Resources
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• v.34 no.3
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• pp.378-386
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• 2014

This study was conducted to determine the effects of red and green glasswort on the physicochemical and textural properties of reduced-salt cooked sausages. The control was formulated with 1.5% NaCl; then, three reduced-salt treatments were prepared, with 0.75% NaCl (RS), 0.75% NaCl+1.0% red glasswort (RSR) and 0.75% NaCl+1.0% green glasswort (RSG), respectively. The addition of glasswort within the added amount of 1% had no influence on the pH value of the reduced-salt cooked sausages, regardless of the glasswort type. In terms of color, RSG treatment conveyed a higher hue angle value than the RSR treatment (p<0.05). Increases in the protein solubility (total and myofibrillar proteins) and apparent viscosity of reduced-salt meat batter that were due to the addition of glasswort were observed; however, there were no differences according to the type of glasswort (p>0.05). Furthermore, the addition of glasswort, regardless of its type, resulted in decreased cooking loss, and increased emulsion stability. As a result, reduced-salt cooked sausages formulated with either red or green glasswort demonstrated similar textural properties to those of the control. In conclusion, the type of glasswort within an added amount of 1% had no influence on the physicochemical and textural properties of reduced-salt cooked sausages, except for the color characteristics. In terms of color alteration by the addition of glasswort, the red glasswort, which in comparison with the green glasswort could minimize the color changes of reduced-salt cooked sausages, might be an effective source for manufacturing meat products.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.161-165
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• 2001

The dietary fiber was extracted from apple pomace with various concentrations of acidic, alkaline solvents and water in $24.4{\sim}29.3%$ yield. The extractions of water-soluble dietary fiber with acidic(6.85%) and alkaline solvent(6.55%) were more effective than the water extraction(6.0%). The higher extraction yield was obtained with increased concentration of acidic or alkaline solvents. The content of galacturonic acid was higher in the order, 0.01 M HCl(77.5%)>0.05 M HCl(76.8%)>$H_2O(76.1%)$>0.05 M NaOH(73.8%)> 0.01 M NaOH(69.0%) and the extraction with acidic solvent showed the highest pectin yield. The color value increased by extraction with solvent in higher concentration. And at equal concentration, the color value of alkaline extract was higher than that of acidic exctract. There was no relationship between the color value and the extraction yield of dietary fiber. In the investigation on the rheological properties, the shear stress increased in proportion to galacturonic acid contents. While water-soluble dietary fiber extracted with acid and water represented Newtonian rheological properties, the alkaline extract was inclined to have converting property from pseudoplastic to Bingham pseudoplastic with increment of alkaline concentration. In the studies on the time-dependence of apparent viscosity, the thixotropic property with hysteresis loop was observed in alkaline extract.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.741-745
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• 2005

Pectin was dissolved in HCl, citric acid, and deionized distilled water (DW, 2%, v/v) and irradiated at different irradiation doses (2.5-50 kGy) by gamma ray to investigate its physicochemical characteristics and biological activity. Viscosity of pectin solution was significantly decreased by irradiation up to 10 kGy, then remained constant thereafter. Gamma-irradiation increased monosaccharide and polysaccharide levels up to 30-40 kDa. Electron donating ability of pectin solution was highest when DW was added and was increased by increasing irradiation dose (p<0.05). ${\beta}-Carotene$ bleaching assay revealed irradiation resulted in development of antioxidantive activity in pectin solution. Growth inhibition of cancer cell lines was observed in irradiated pectin solution in dose-dependent manner, with G36l showing the highest. Results suggested irradiation of pectin solution could be effective for preparation of functional pectin oligomer.

• Journal of the Korean Geosynthetics Society
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• v.16 no.2
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• pp.149-158
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• 2017

Permeating injection is commonly known as an ideal type of injection in grouting reservoir embankment, yet often-combined permeating and fracturing injection grouting operation can disturb the original soil. A grouting method has been regarded as effective and developed to ameliorate the possible disturbance problem. It involves compaction grouting with low expansive pressure near the injection hole and repetitive injection and compaction with grout material that allows ideal permeating injection. This thesis develops Hybrid Grout (ie. HG grout) that allows various application in any ground condition combined together, has high fineness and low viscosity, and expands permeation injection to silty sand. It researches on the injection effect of permeable compaction grout which is done with PC packer and is a combination of HG grout and expansion agent to obtain permeation compaction effect on the area near grout injection spot by developing Permeable Compaction Type Packer(ie. PC packer). As the developed PC packer, HG grout, and and expansion agent (HI-E) are applied to reservoir embankment reinforcement grouting, possibile permeation compaction effect that satisfies reservoir embankment grouting standard is confirmed according to the research.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1565-1570
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• 2012

The effects of emulsifiers as additives on the physical properties of rice cookies were investigated in this study. The amounts of emulsifiers added were 3, 6, and 9% based on 100 g of rice flour. Peak viscosity of rice flour added with diacetyl tartaric ester of monoglyceride (DATEM) showed smaller decreases compared to addition of sodium stearoyl lactylate (SSL) or sucrose ester (SE). Hardness of dough as measured by TA increased upon addition of SSL, SE, and DATEM, whereas hardness of cookies increased upon addition of SSL and SE. In contrast, addition of DATEM did not increase hardness of cookies. Density of dough and cookies increased upon addition of SSL and SE, whereas density decreased upon addition of DATEM and spreadability showed the lowest values. From these results, it was confirmed that use of emulsifiers in cookies can control cookie texture. Compared to SSL and SE, DATEM increases hardness of dough and decreases densities of dough and cookies, making it effective in softening the texture of rice cookies.

• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.129-135
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• 2010

We described production of bioactive compounds from fungi grown on Korean ginseng-steaming effluents (GSE) for develop high-value added nutraceuticals from Korean GSE. Hansenula anomala KCCM 11473, which grew well in Korean GSE had high RNA content, and its optimal autolysis conditions were established to produce 5'-ribonucleotides (13.9~28.5 mg/g of biomass) at $55^{\circ}C$ and pH 5.0 for 24 h. 5'-Phosphodiesterase and adenyl deaminase were not effective in increasing the yield of 5'-ribinucleatides, but the yield of IMP increased significantly only after the addition of 1.0% adenyl deaminase. Saccharomyces cerevisiae showed the highest growth in the GSE medium. 267.1 mg of S. cerevisiae biomass was produced from 1 g of GSE solid and medicinal ginsenoside-$Rg_3$ contents was determined with 0.033 mg. Mucor miehei KCTC 6011 produced approximately 120 mg of chitosan per g-dry mycelium in 84 h at $25^{\circ}C$ when grown in the GSE (pH 8.0) supplemented with 0.5% yeast extract and 0.002% $CuSO_4$. Chitosan produced by M. miehei KCTC 6011 have deacetylated approximately 56% and its viscosity and molecular weight of the chitosan were 80 cps and $1.07\times10^3$ kDa, respectively. The chitosan at 1.5 mg/ml inhibited 73.9% of the mycelium growth of Rhizotonia solani in 60 h.