• Journal of Aquaculture
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• v.16 no.4
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• pp.262-266
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• 2003

In order to develop a method for the cryopreservation of fish embryos, the determination of optimal concentrations of dimethyl sulfoxide (DMSO), ethylene glycol and glycerol as individual cryoprotectants was performed by using the early embryos of black seabream, Acanthopagrus schlegeli. Optimal concentrations of cryoprotectants were assessed in terms of effects on mortality, median lethal concentration and hatching rate of embryos. The mortality of black seabream embryos immersed in cryoprotectants was related to the concentrations of cryoprotectants and immersion times. The toxicity to embryos was lower in order of DMSO, < ethylene glycol, < glycerol. The results from the mortality, median lethal concentration and hatching rate evaluations suggest that DMSO was the most effective cryoprotectant for black seabream embryos followed by ethylene glycol, and suitable concentrations of DMSO and ethylene glycol were 2.0∼2.25M and 1.0∼1.78M, respectively, with 20 minutes of immersion time.

• Journal of Environmental Health Sciences
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• v.27 no.3
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• pp.43-48
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• 2001

Terephthalic acid and ethylene glycol resulting form the weight-reduction process of polyester make trouble in the operation of activated sludge process. Also, polyester weight loss wastewater shows high pH, high organic strength and wide variation of organic loading. Therefore, this study was conducted in order to improve treatment efficiency by activated sludge process with Pseudomonas sp degrading components of polyester weight loss wastewater. The CO $D_{Mn}$ and BO $S_{5}$ of the waste wastewater were 560~3,000 mg/$\ell$ and 8000~3,000 mg/$\ell$, respectively. pH was 11.8~12.3. COD removal efficiency by activated sludge-coagulation process with Pseudomonas sp was 94.1~95.8% for 35 hr of hydraulic retention time. Total organic carbon removal efficiency was 97.1%. Ethylene glycol and terephthalic acid in the wastewater were completely degraded during 32 hr of hydraulic retention time.e.

• Journal of the Korean Solar Energy Society
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• v.23 no.4
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• pp.45-54
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• 2003

For cooling of double effect absorption heat pump system of solar heating source, analysis of thermodynamic design data has been done to find the property of Libr-water + ethylene Glycol mixture for working fluid by computer simulation. Derived thermodynamic design data, enthalpy based coefficient of performance and flow ratio for possible combinations of operating temperature for water - LiBr and Ethylene Glycol mixture ($H_2O$ : CHO ratio 10:1 by mole) by computer simulation are done. The obtained results, COP and mass flow ratio of the water - lithium bromide - ethylene glycol system, are compared with data for the water-Libr pair solution.

• Journal of the Korean Solar Energy Society
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• v.22 no.4
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• pp.51-61
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• 2002

Analysis of thermodynamic design data of double effect solar absorption heat pump system for heating has been done to find the property of Libr-water + ethylene Glycol mixture for working fluid by computer simulation. Derived thermodynamic design data. enthalpy based coefficient of performance and flow ratio for possible combinations of operating temperature for water - LiBr and Ethylene Glycol mixture (H2O: CHO ratio 10:1 by mole) by computer simulation. The obtained results, COP and mass flow ratio of the water-lithium bromide-ethylene glycol system, are compared with data for the water-Libr pair solution.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.140-146
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• 2016

Using density functional Theory, we studied local structure of liquid ethylene glycol and 1,3-propanediol. For both liquid, making intramolecular hydrogen bonding is not preferred, because relative energy between with and without intramolecular hydrogen bond is only -1.95kcal/mol, which is far less than intermolecular hydrogen bonding energy, about -7.5kcal/mol. Also, hydrogen bond induce polarization of hydroxyl group and make $2^{nd}$ hydrogen bond more stronger. This effect was small in intramolecular hydrogen bond of ethylene glycol. When considering energy per hydrogen bond, making only one intermolecular hydrogen bond for ethylene glycol pair is energetically favored, while two intermolecular hydrogen bond can be formed in 1,3-propanediol pair.

• Macromolecular Research
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• v.9 no.6
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• pp.332-338
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• 2001

Waterborne polyurethane as a new polymer electrolyte was synthesized by using relatively hydrophilic polyols. The morphology of polyurethane was changed as it was dispersed in water. In contrast to polyurethane ionomer, waterborne polyurethane did not form an ionic cluster but produced a binary system composed of hydrophilic and hydrophobic groups. In the colloidal system, the former and the latter existed at outward and inward, respectively. Waterborne polyurethane was prepared from poly(ethylene glycol) (PEG) /poly(propylene glycol) (PPG) copolymer, 4,4'-diphenylmethane diisocyanate(MDI), ethylene diamine as a chain extender, and three ionization agents, 1,3-propane sultone, sodium hydride and lithium hydroxide. PEG/PPG copolymer was used for suppressing the crystallinity of PEG and N-H bond was ionized for increasing the electrochemical stability of polyurethane. Low molecular weight poly(ethylene glycol) and poly(ethylene glycol dimethyl ether) (PEGDME) were used as plasticizers. DSC, FT-IR and $^1$H-NMR of the waterborne polyurethane were measured. Also, the ionic conductivity of solid polymer electrolytes based on waterborne polyurethane and various concentrations of low molecular weight poly(ethylene glycol) or PEGDME were measured by AC impedance.

• Journal of Electrochemical Science and Technology
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• v.7 no.1
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• pp.58-67
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• 2016

The corrosion behavior of duplex stainless steel AISI 2205 was investigated in ethylene glycol-water mixture in the presence of 50 W/V % LiBr at different concentrations and different temperatures. Cyclic polarization, impedance measurements and Mott-Schottky analysis were used to study the corrosion behavior the semi conductive properties of the passive films. The results showed that with increasing in the ethylene glycol concentration to 10 V/V%, the corrosion rate of the steel alloy substrate increased. In higher concentrations of ethylene glycol, corrosion current of steel decreased. The results of scanning electron microscopy of electrode surface confirmed the electrochemical tests. Electrochemical experiment showed that duplex steel was stable for pitting corrosion in this environment. The increase in the ethylene glycol concentration led to increasing the susceptibility to pitting corrosion. The corrosion current increased as the temperature rise and also pitting potentials and repassivation potentials shifted towards the less positive values as the temperature increased. According to Mott-Schottky analysis, passive films of stainless steel at the different temperatures showed both n-type and p-type semiconductor behavior in different potential.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.806-808
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• 2004

A gas chromatography/mass spectrometric assay method has been developed for the simultaneous determination of icing inhibitors, ethylene glycol monomethyl ether and diethylene glycol monomethyl ether in ground water contaminated with JP-8. Ethylene glycol monobutyl ether and ethylene glycol monoethyl ether were used as the internal standard and surrogate, respectively. 100 mL of ground water was extracted twice with 20 mL of methylene chloride. The extract was concentrated to dryness, dissolved with 100 ${\mu}$L of methanol and analyzed by GC-MS (SIM). The use of an Innowax column gave the peaks good chromatographic properties, and the extraction of these compounds from samples gave recoveries of about 50% with small variations. The method detection limits of the target compounds were in a range of 0.5-0.8 ng/mL in ground water.

• Fire Science and Engineering
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• v.30 no.1
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• pp.24-30
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• 2016

Autoignition characteristic is an important factor of all combustible substances, and a critical determinant in assessing the effectiveness of fire hazard prevention. This study investigated the autoignition characteristic of mixtures of Ethylene Glycol and water using an ASTM D2155 type ignition temperature measuring apparatus. It was possible to get the minimum temperature as $434^{\circ}C$ from 100% Ethylene Glycol within range of $75{\sim}160{\mu}l$. A volume of $100{\sim}125{\mu}l$ of a mixed sample of Ethylene Glycol and water (80 : 20) was ignited at the same temperature ($434^{\circ}C$). Also it was possible to get the auto ignition temperature as $437^{\circ}C$ from a mixed sample of Ethylene Glycol and water (60 : 40) within range of $120{\sim}160{\mu}l$. The instantaneous ignition temperatures determined for $125{\mu}l$ of each of the three samples were $579^{\circ}C$, $595^{\circ}C$ and $611^{\circ}C$, respectively. Both auto ignition temperatures and instantaneous ignition temperatures were increased through the addition of water to the samples.

• Journal of the Korean Electrochemical Society
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• v.18 no.4
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• pp.150-155
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• 2015

In this study polymer electrolytes containing ethylene carbonate group which have a high dielectric constant and poly(ethylene glycol) as branches were prepared by the Williamson reaction between poly(ethylene glycol) methyl ether and block copolymers composed of glycerol-1,2-carbonate and 4-chloromethyl styrene. Interestingly, the highest ionic conductivity of $1.75{\times}10^{-5}S\;cm^{-1}$ was observed from the polymer electrolyte having 7 mol% of ethylene carbonate and the [EO]:[Li] ratio of 32:1. Moreover, it was found that the electrochemical stability of polymer electrolyte was achieved up to 5.5 V because of the presence of ethylene carbonate.