• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.176-176
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• 2009

Influences of dose and particle size of $Al_2O_3$ filler and sintering time on the dielectric properties of $Al_2O_3$ filler/CaO-$Al_2O_3-SiO_2$ (CAS) glass composites were investigated with a view to applying the composites to the substrate material in low temperature co-firing ceramic (LTCC) technology. The increased addition of $Al_2O_3$ filler with the particle size of 1 ${\mu}m$ monotonically decreased the density of the sintered specimen at a given temperature, while sintering of the 10 wt% $Al_2O_3$ added specimen at $925^{\circ}C$ for 2 h demonstrated 96.0 % of the relative density, dielectric constant of 6.34, and quality factor of 2,760 GHz. As for the influence of the particle size of the $Al_2O_3$ filler, there existed an optimum particle size (30 ${\mu}m$) to ensure successful densification (96.5 %) of the 10 wt% $Al_2O_3$/CAS composites at $925^{\circ}C$ for 2 h, at which condition the specimen demonstrated dielectric constant of 5.45 and quality factor of 3,740 GHz. When the influence of the sintering time of the 10 wt% $Al_2O_3$) (30 ${\mu}m$) added specimen was investigated at the sintering temperature of $925^{\circ}C$, an overly long sintering time degraded dielectric properties due to the over-sintering and the significant growth of the second phase such as anorthite, while the sintering for 4 h demonstrated 96.58 % of the relative density, dielectric constant of 5.4, and quality factor of 4,050 GHz. These results demonstrate the feasibility of the investigated material as the substrate material in LTCC technology.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.687-694
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• 2012

$Jeot-gal$ is a traditional Korean fermented seafood with a salt concentration of 15~20%. However, today's consumers prefer low-salted foods as they have become aware that high levels of salt cause hypertension and diabetes. In this study, the quality characteristics and shelf-life of low-salted squid $Jeot-gal$ were investigated at different fermentation temperatures and salt concentrations. The shelf-lives of 3%-salted squid $Jeot-gal$ fermented at -1, 4, and $10^{\circ}C$ were 45, 31, and 23 days, respectively, whereas those of 5%-salted squid $Jeot-gal$ were 52, 36, and 25 days. The DPPH radical scavenging activity of the ethanol extract of squid $Jeot-gal$ was stronger than that of the water extract. However, the other antioxidative activities, such as hydrogen peroxide and hydrogen peroxide radical scavenging activities, as well as enzyme inhibitory activities were very low at 20 mg/mL of water and ethanol extracts. Based on the results of the sensory evaluation, the quality of low-salted fermented squid $Jeot-gal$ was almost similar to that of commercial squid $Jeot-gal$ with a high salt concentration.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.393-397
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• 2012

This study developed a rapid egg-salting method using a temperature change in NaCl solution under pressure. The permeation effects(PEs) of NaCl into eggs at ambient pressure were analyzed 1) after soaking them in 20, 30, or 40%(w/v) NaCl solution at $50^{\circ}C$ and 2) after soaking in 20~40% concentrations(w/v) of NaCl solution at $4^{\circ}C$ immediately after soaking at $50^{\circ}C$ for 1 hr(temperature change method; TCM). Under permeation conditions(40% NaCl solution with TCM), the PE of NaCl into eggs at various pressures(4.0~7.0 MPa) was determined. The PE improved with increasing NaCl concentration and pressure. In 40%(w/v) NaCl solution, the PE was more rapid with TCM(0.70% for 2 hr) than without TCM(0.60% for 2 hr). At 7.0 MPa pressure, the PE was more rapid with TCM(1.66% for 15 min) than without TCM(1.40% for 15 min). These results suggest that the TCM-induced contraction of the egg membrane improved the PE. Therefore, we believe that the development of a rapid salting method for seasoning eggs is possible with the TCM.

• Journal of Yeungnam Medical Science
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• v.6 no.1
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• pp.121-131
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• 1989

The temperature-corrected values of blood gas analysis were compared to uncorrected values in 40 cases of open heart surgery under moderate hypothermic cardiopulmonary bypass. The results were as follows. 1. The corrected value of pH was significantly higher than uncorrected value, and it's relationship was ${\Delta}pH=-0.015$ ${\Delta}Temp+0.005$(r=0.81, P<(0.01). 2. The corrected value of $PCO_2$ was lower than uncorrected value, and it's relationship was ${\Delta}PCO_2=1.11$ ${\Delta}Temp+1.81$(r=0.50, P<0.01). 3. The corrected value of $PO_2$ was lower than uncorrected value, and it' s relationship was ${\Delta}PO_2=5.21$ ${\Delta}Temp-1.45$(r=0.32, P<0.01). But there was no clinical significance. 4. The corrected values of $HCO_{3^-}$, base excess, $CO_2$ content and oxygen saturation were similar with uncorrected values. In summery, the values of pH and $PCO_2$were significantly changed by temperature-correction. Because of the neutral point of water (pH=pOH) rises as temperature falls and it change in parallel with the changes in blood pH, a corrected pH of 7.4, $PaCO_2$ of 40mmHg during deep hypothermia would reflect a profound respiratory acidosis. Therefore, the use of the uncorrected value at $37^{\circ}C$ is more preferable and valid means of assessing acid-base management regardless of actual patient temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.1
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• pp.40-50
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• 1990

The purpose of this paper is to develop a colorant from krill, Euphausia superba, process wastes for use in food products. Carotenoproteins were extracted from preboiled krill processing offal(PKPO) and raw frozen krill processing offal(RKPO) with the aid of proteolytic enzymes. The long-term stability of the astaxanthin associated with the carotenoprotein by the addition of pretense inhibitor and antioxidant to the product were also investigated. Total astaxanthin contents of PKPO and RKPO were $35.1mg\%,\;22.1mg\%$ and those in carotenoproteins were $98.6mg\%,\;61.9mg\%$, respectively. The chitin contents of PKPO and RKPO were $6.9\%,\;4.5\%$, however, those of carotenoproteins were not determined. When $0.5\%$ trypsin was added to the extraction medium containing 0.5M $Na_3EDTA$ at $4^{\circ}C,\;74\%$ of astaxanthin and $83\%$ of the protein of PKPO were recovered as carotenoprotein in 24hrs. The amino acid profile in carotenoprotein was mainly composed of glutamic acid, methionine, aspartic acid and isoleurine. Their contents amounted to about 40% of the total amino acids, followed by alanine, phenylalanine, Iysine, leucine, threonine and tyrosine in that order, with a small amount of cysteine and tryptophan. The levels of essential amino acids were high as much as $38.3\%\~43.6\%$ of the total amino acids. The maximum observance of the carotenoid fraction from krill processing offal and from carotenoprotein was 469nm in petroleum ether. The separated components of carotenoprotein by TLC had Rfs $0.20\~0.23\;0.56\~0.60$ and $0.88\~0.91$. The carotenoids were comprised of astaxanthin, astaxanthin monoester and asthaxanthin diester in $25\~30\%\;,35\~40\%$and $40\~45\%$, respectively. The loss of carotenoids in the carotenoprotein can be prevented by the addition of pro-tease inhibitor(trasylol) and antioxidant(BHT) below $4^{\circ}C$.

• Journal of the Korean Electrochemical Society
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• v.6 no.1
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• pp.41-47
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• 2003

For the development of low temperature anode-supported planar solid oxide fuel cell, the planar anode supports with the thickness of 0.8 to 1 mm and the area of 25, 100 and $150\;cm^2$ were fabricated by the tape casting method. The strength, porosity, gas permeability and electrical conductivity of the planar anode support were measured. The porosity of anode supports sintered at $1400^{\circ}C$ and then reduced in$H_2$ atmosphere was increased from $45.8\%\;to\;53.9\%$. The electrical conductivity of the anode support was $900 S/cm\;at\; 850^{\circ}C$ and its gas permeability was 6l/min at 1 atm in air atmosphere. The electrolyte layer and cathode layer were fabricated by slurry dip coating method and then had examined the thickness of $10{\mu}m$ and the gas permeability of 2.5 ml/min at 3 atm in air atmosphere. As preliminary experiment, cathode multi-layered structure consists of LSM-YSZ/LSM/LSCF. At single cell test using the electrolyte layer with thickness of 20 to $30{\mu}m$, we achieved $300\;mA/cm^2$ and 0.6V at $750^{\circ}C$

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.35-44
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• 1987

Differing in water conditions, the dry matter weight per plant was highest at 0 cm flooding depth, and was decreased at above 2 cm flooding depths. The shoot and spikes per pot developed best at flooding depths of 0 and 2 cm, but worst at -5cm or above 4cm flooding depths. The dry matter weight of shoots was linearly increased, but the weight of roots was sharply decreased according to high temperature after flower initation. The shoots and spikes per pot developed more effectively at 25$^{\circ}C$ than at 35 or 15$^{\circ}C$. The number of shoot and spike per pot were decreased according to higher shading. The effects of shading of 25-45% were not significantly small. The natural white and yellow spectra were the most effective to increase dry matter weight, shoots and spikes per pot. The dry matter weights of shoot and root per plant were not significantly different among at: 50 and 75% clay. The number of shoots were best and continuously increased at 75% clay, and the increments at 0 and 100% clays showed the lag period at early stage. The pattern of spikes was similar to shoots with less difference in various clay composition. The dry matter weight per plant in paddy field and upland field was basically similar. The numbers of shoot and spike were increased in response to increased fertilizer levels up to 20Kg per 10a of each component.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.3
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• pp.169-172
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• 2003

Intact seeds of burcucumber (Sicyos angulatus L.) are not nearly germinated so that the farmers remove their arils before sowing. The study was carried out to measure the effort of aging, chilling, washing, chemical treatment, drying, and their sequential treatments on the germination of ones with arils and the seedling emergence. The seeds extruding over 1mm of their radicles and the seedlings with fully expanded cotyledons were counted daily for calculating the germination and the seedling emergence rates. Seedcoat softening using 10% NaOH solution somewhat enhanced their germination rate of the intact seeds harvested in the current year, but aging treatment done on 6 days at $45^{\circ}C$ after NaOH treatment increased the germination rate more than only NaOH treatment. A day washing after the NaOH treatment and a day chilling after the washing increasingly elevated the rates as well. Irrigation of 0.2% $\textrm{KNO}_3$ solution, moreover, showed the greatest germination rate of the priming treatments done during all the 7 day chilling. Drying the seeds after the combined treatment of chilling and priming more inclined the germination rate than nondrying ones, but red light treated during 24 hour desiccation was more effective in the germination rate increment than dark condition. The seeds done the sequential treatments of aging, NaOH, washing, combining chilling and priming and drying under red light illumination were germinated up to 80% but seedlings were emerged to 60%, lower than ones removed their arils.

• Korean Journal of Food Science and Technology
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• v.45 no.5
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• pp.605-612
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• 2013

We investigated changes in the nutrient compositions of seokbakji supplemented with seafood during storage at $5^{\circ}C$ for 14 days. We added the seafood at a concentration of 10% (w/w) to salted radish and prepared seokbakji samples. Our results showed that the levels of moisture, crude lipids, crude ash, carbohydrates, and crude fibers did not differ markedly among the samples. However, the level of crude protein in seokbakji with added seafood was greater than that in control seokbakji. The highest level of Ca and P was determined in seokbakji supplemented with gizzard shad; the highest level of vitamin $B_2$ was determined in seokbakji supplemented with sandfish, and the highest vitamin C content was determined in seokbakji supplemented with small octopus. Glutamic acid showed the highest content in seokbakji with seafood; further, hydroxyproline was the most abundant free amino acid. The results of sensory evaluation showed higher scores in the overall acceptability of seokbakji with seafood than in control seokbakji.