• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.211-215
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• 1997

Experiments were performed to find out the proper conditions of diluents for the short-tenn storage of sperm of black seabream, Acanthopagrus schlegeli. For milt collection, brood stock was reared in a recirculating seawater system. The following results indicated that short-term storage methods with fresh condition could tie employed in black seabream sperm. When the black seabream's serum was used as a diluent for the fresh storage, sperm activity index (SAI), fertilization rate and survival rate derived the best result in $7\~10\;days$ of storage. pH 7 and 8 showed the highest SAI in the same storage condition. In order to keep high SAI and survival rate of the sperm, addition of 800 ppm neomycine into the diluent revealed the best storage results.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1132-1136
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• 1999

This study was performed to offer fundamental data for concentration of persimmon vinegar. The $5.4^{\circ}Bx$ raw persimmon vinegar was concentrated to $20^{\circ}Bx$, $30^{\circ}Bx$, $40^{\circ}Bx$, $50^{\circ}Bx$, $60^{\circ}Bx$ and $70^{\circ}Bx$ concentration by vacuum concentration at $55^{\circ}C$ and diluted to $5.4^{\circ}Bx$ solution with distilled water. The physicochemical properties such as color, viscosity, pH, acidity, organic acid content and free sugar content of various persimmon vinegar concentrates were examined. The recovery yield of water soluble solid to concentrates was 55.5% on $20^{\circ}Bx$ vacuum concentration. Color of $5.4^{\circ}Bx$ persimmon vinegar diluents from concentrates became more dark brown by vacuum concentration. Flow behavior of persimmon vinegar concentrates was pseudoplastic. As the concentration of persimmon vinegar concentrates increased, pH of $5.4^{\circ}Bx$ diluents increased and acidity as acetic acid decreased compared to original raw vinegar. Acetic acid, lactic acid and citric acid were detected, malic acid and oxalic acid were not detected in persimmon vinegar concentrate. Fructose and sucrose only were detected in persimmon vinegar concentrate.

• Journal of Aquaculture
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• v.20 no.3
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• pp.173-177
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• 2007

An experiment was performed to obtain cryopreservation techniques of starry flounder (Platichthys stellatus) sperm. Milt obtained from 24 males were cryopreserved using two diluents, artificial seminal plasma (ASP) and Stein's solution (SS) with three cryoprotectants, dimethyl sulfoxide (DMSO), methanol, and glycerol concentrated from 5% to 20%. Post-thaw sperm activity (motility and/or speed) revealed the highest in 10% DMSO and 15% methanol in ASP and SS as diluent. Motility and speed of cryopreserved sperm were decreased according to increase of glycerol concentration. To conclude, DMSO was a better cryoprotectant than methanol or glycerol for cryopreservation of starry flounder sperm. Glycerol was incongruent cryoprotectant because of toxic to starry flounder sperm. Most cryopreserved spermatozoa without cryoprotectant showed the enlarged head with granulated chromatin and ruptured plasma membrane by freezing and thawing injuries compared with unfrozen normal spermatozoa.

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.5
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• pp.72-83
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• 2010

Experiments were conducted to investigate the effects of added diluents (carbon dioxide, nitrogen, and helium) on cellular instabilities in outwardly propagating spherical syngas-air premixed flames. Laminar burning velocities and Markstein lengths were measured by analyzing high-speed schlieren images at various diluent concentrations and equivalence ratios. Experimental results showed substantial reduction of the laminar burning velocities and of the Markstein lengths with the diluent additions in the fuel blends. Effective Lewis numbers of helium-diluted syngas-air flames increased but those of carbon dioxide- and nitrogen-diluted syngas-air flames decreased in increase of diluents in the reactant mixtures. With helium diluent, the propensity for cells formation was significantly diminished, whereas the cellular instabilities for carbon dioxide- and nitrogen-diluted syngas-air flames were not suppressed.

• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.57-63
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• 2006

This study was carried out to investigate control efficacy of natural compound, TGR-N1 against turfgrass fungal diseases. TGR-N1 showed antimicrobial activity in vitro. Rhizoctonia solani AG 1-1, Rhizoctonia solani AG2-2, Rhizoctonia cerealis, Sclerotinia homoeocarpa and Colletotrichum graminicola were inhibited by 500 times and 1,000 times of diluents of TGR-N1. Pythium spp. was not inhibited by the same diluents of TGR-N1. The TGR-N1 also showed a remarkable antifungal activity against Rhizoctonia solani AG 1-1, Rhizoctonia solani AG2-2 in field. This study proved the antifungal activity of natural compound, TGR-N1 and showed its potential as a natural pesticide.

• Korean Journal of Materials Research
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• v.25 no.12
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• pp.659-665
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• 2015

The self-propagating high temperature synthesis approach was applied to synthesize amorphous boron nano-powders in argon atmospheres. For this purpose, we investigated the characteristics of a thermally induced combustion wave in the $B_2O_3+{\alpha}Mg$ system(${\alpha}=1.0-8.0$) in an argon atmospheres. In this study, the exothermic nature of the $B_2O_3-Mg$ reaction was investigated using thermodynamic calculations. Experimental study was conducted based on the calculation data and the SHS products consisting of crystalline boron and other compounds were obtained starting with a different initial molar ratio of Mg. It was found that the $B_2O_3$ and Mg reaction system produced a high combustion temperature with a rapid combustion reaction. In order to regulate the combustion reaction, NaCl, $Na_2B_4O_7$ and $H_3BO_3$ additives were investigated as diluents. In an experimental study, it was found that all diluents effectively stabilized the reaction regime. The final product of the $B_2O_3+{\alpha}Mg$ system with 0.5 mole $Na_2B_4O_7$ was identified to be amorphous boron nano-powders(< 100 nm).

• The Korean Journal of Malacology
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• v.20 no.1
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• pp.17-26
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• 2004

In present study, attempts were made to preserve abalone (Haliotis discus hannai) sperm in liquid form at low temperature, to evaluate the effect of various diluents in short-term storage on sperm, and cryopreservation procedures were optimized for the cryoprotectants and freezing rates, as well as the motility, survival rate, and the ultrastructural changes of sperm after short-term storage and cryopreservation were observed. The abalone sperm reached maximum motility until about 4 min after activation. The motility was constant for about 16 min, after which it dropped gradually, and about 50 min later all motility ceased. In Hanks' balanced salt solution (HBSS, 300 and 400 mOsmol/kg) and 150, 250 and 350 mOsmol/k artificial seawater (ASW), the sperm was immotile. After 100% ASW was added, motility of those sperm, which are in 300, 400 mOsmol/kg HBSS, 250, 350 mOsmol/kg ASW, could be again restored incompletely. Sperm motility can be maintained for 20 days of cold storage only in ASW of 850 and 1200 mOsmol/kg. A high motility index of 3.5-4.5 was observed for the first 8 days in 850 and 950 mOsmol/kg ASW. In other diluents sperm motility was constant less than 10 days, and the motility index was obviously lower than that of sperm in 850 and 1200 mOsmol/kg ASW. After 20 days of cold storage, survival rates of 10.2%-20.7% were obtained in ASW and 300 mOsmol/kg HBSS, and that in 400 HBSS (65.3%) was significantly higher than others. The constant period of sperm motility stored in 850 mOsmol/kg ASW was obviously longer than that in 1200 mOsmol/kg ASW after 6 days of storage. The sperm plunged into liquid nitrogen all died except that sperm using 15% glycerol as cryoprotectant restored 10.4% of motility. The highest motility index (3.4) was obtained with 5% glycerol and freezing procedure: $-50^{\circ}C$/min from $20^{\circ}C$ to $-80^{\circ}C$.

• Journal of Adhesion and Interface
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• v.17 no.2
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• pp.67-71
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• 2016

In this study, low-viscosity polyurethane hot-melt were synthesized with polyether polyol / polyester polyol, 4,4-dicyclohexylmethane diisocyanate ($H_{12}MDI$), 2-butanone oxime (MEKO) to improve the properties and peel strength. The properties of the synthesized low-viscosity polyurethane hot-melt was evaluated through FT-IR, viscosity meter and UTM. When the content of the reactive diluent increases and the NCO-blocked prepolymer decreases, the viscosity of low-viscosity polyurethane hot-melt adhesive was increased. When the ratio of OH-terminated oligomer, NCO-blocked prepolymer and content of reactive diluent is 1 : 0.5 : 0.5, low-viscosity polyurethane hot-melt showed 1.1 kgf/cm peel strength.

• Korean Journal of Materials Research
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• v.24 no.5
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• pp.255-258
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• 2014

Zirconium boride is an artificial or which is rarely found in the nature. $ZrB_2$ is popular in the hard material industry because it has a high melting point, excellent mechanical properties and chemical stability. There are two known methods to synthesize $ZrB_2$. The first involves direct reaction between Zr and B, and the second is by reduction of the metal halogen. However, these two methods are known to be unsuitable for mass production. SHS(Self-propagating High-temperature Synthesis) is an efficient and economic method for synthesizing hard materials because it uses exothermic reactions. In this study, $ZrB_2$ was successfully synthesized by subjecting $ZrO_2$, Mg and $B_2O_3$ to SHS. Because of the high combustion temperature and rapid combustion, in conjunction with the stoichiometric ratio of $ZrO_2$, Mg and $B_2O_3$; single phase $ZrB_2$ was not synthesized. In order to solve the temperature problem, Mg and NaCl additives were investigated as diluents. From the experiments it was found that both diluents effectively stabilized the reaction and combustion regime. The final product, made under optimum conditions, was single-phase $ZrB_2$ of $0.1-0.9{\mu}m$ particle size.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.393-396
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• 2008

The study of nitrogen dilution effect on flame stability was experimentally investigated in non-premixed turbulent lifted hydrogen jet with coaxial air. hydrogen gas was used as a fuel and coaxial air was injected to make flame liftoff. And both of the fuel jet and coaxial air velocity were fixed as $u_F$=200 m/s and $u_A$=16 m/s, while nitrogen diluents mole fraction was varied from 0 to 0.2. For the analysis of flame structure and flame stabilization mechanism, the simultaneous measurement of PIV/OH PLIF had been performed. It was found that the turbulent flame propagation velocity increased as decreasing of nitrogen mole fraction. We concluded that the turbulent flame propagation velocity was expressed as a function of turbulent intensity, even though the mole fraction of nitrogen diluents gas was changed.