• 전기의세계
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• v.30 no.6
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• pp.357-365
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• 1981

When electronegative gas SF$_{6}$ is dissolved and charged with insulating oil, the effect caused in the process by electronegative characteristic is studied and also the pressure effect caused by electronegative SF$_{6}$ acting on the liquid-level is examined respectively. When inert gas Ar is used to find a pressure effect acting on the liquid-level, its effect on dielectric strength is considered in the experiment. With three kinds of impulse voltage different in the duration of wave front and wave tail, a brief experiment if carried out ot see the effects on the dielectric breakdown characteristic as the wave is changing; either if I$_{2}$ and SF$_{6}$ are added to the insulating oil, or if the oil pressure is increased by Ar the dielectric strength becomes great and the longer the duration of wave front is, the greater the increase of the breakdown voltage, because I$_{2}$ added by a small quantity brings about some hirderance in the formation of gas phase. Likewise, the greater the changed pressure is, the greater the incerase of the breakdown voltage. When SF$_{6}$ is charged, the electronegative characteristic is prevailing at the time of low balanced pressure, and the pressure effect at the time of high balanced pressure.ressure.

• Korean Journal of Microbiology
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• v.44 no.1
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• pp.22-28
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• 2008

Cutting oils are emulsionable fluids widely used in metal working processes. Their composition is mineral oil, water, and additives (fatty acids, surfactants, biocides, etc.) generating a toxic waste after a long use. Cutting oils also affect colour, taste and odour of water, making it undesirable for domestic and industrial uses. In these days, conventional treatment methods as evaporation, membrane separation or chemical separation have major disadvantages since they generate a concentrated stream that is more harmful than the original waste. In this study, our purpose is to reduce cutting oils by using biological treatment. Eighty one strains were isolated from cutting waste oil of industrial waste water sludge under aerobic conditions. Among these strains, KS47, which removed 90.4% cutting oil in 48 hr, was obtained by screening test under aerobic conditions(pH 7, $28^{\circ}C$). KS47 was identified as Pseudomonas aeruginosa according to morphological, physiological and biochemical properties, 16S rDNA sequence, and fatty acid analysis. P. aeruginosa KS47 could utilize cutting oil as carbon source. In batch test, we obtained optimal degradation conditions(1.5 g/L cell concentration, pH 7, and temperature $30^{\circ}C$). Under the optimal conditions, 1,060 mg/L cutting oil was removed 83.7% (74.1 mg/L/hr).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.5
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• pp.69-78
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• 2014

The paper recycling becomes more important technology in terms of the reduction of the municipal waste and of saving natural resource such as wood. However the more utilization of recycled fiber would result in the higher contaminants in the papermaking processes and in the deterioration of the paper quality. The oil marks in the paper products becomes one of the major defects of paper products originated from paper recycling. The coagulation of various stickies in recycled fiber stock led to the oil marks. In this work, we applied functional polymer additives such as the dispersing agents, the fixing agents and the hydrophobic talc powder for the control of those stickies in order to remove the oil marks. The addition of the talc powder showed the great reduction in the oil marks of the packaging paper products. The hydrophobic surface of the talc particles collected the individual sticky materials and prevented their aggregation in the recycled fiber stock, which resulted in the great reduction of the oil marks on the paper products.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.5
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• pp.98-104
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• 2022

When processing parts, the cutting oil can improve the cooling performance of the workpiece and tool to increase the precision of the workpiece or extend the life of the tool and facilitate chip extraction. Since such cutting oil has a harmful effect on the environment and the human body due to additives such as sulfur, research on a minimum lubrication supply method using an eco-friendly oil is recently underway. The minimum lubrication supply method minimizes the amount of cutting oil used during processing and processes it, which can reduce the amount of cutting oil used, but has a problem in that cooling performance efficiency is poor. Therefore, this study conducted a study on mist cooling of lubricants to reduce the amount of cutting oil used and maximize the cooling effect of processing heat generated during tapping processing. Spray pressure, processing speed, direction, and lubricant spray amount, which are considered to have an effect on cooling performance, were set as process conditions, and the effect on temperature was analyzed by performing an experiment using the box benquin method among experiments were analyzed. Through the experimental analysis results, the optimal conditions for mist and processing that maximize the cooling effect were derived, and the validity of the results derived through additional experiments was verified. In the case of processing by applying the mist lubrication method verified through this study, it is considered that high-precision processing is possible by improving the cooling effect.

• Journal of Animal Science and Technology
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• v.65 no.3
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• pp.535-549
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• 2023

This study was to investigate the effects of different phytogenic feed additives (PFA) dosage levels in growing- finishing pigs stressed by high stocking density. A total of 72 mix sexed 12 weeks growing pigs ([Landrace × Yorkshire] × Duroc) with initial body weight (BW) of 49.28 ± 4.58 kg were used for 8 weeks. There were 3 replicate pens in each treatment group, with 3 pigs per pen. The dietary treatment groups consisted of basal diets in animal welfare density (negative control [NC]), basal diet in high stocking density (positive control [PC]), PC + 0.04% essential oil (ES1), PC + 0.08% essential oil (ES2), PC + 0.10% bitter citrus extract & essential oil (CES1), PC + 0.20% bitter citrus extract & essential oil (CES2), PC + 0.05% grape pomace extract (GP1), PC + 0.10% grape pomace extract (GP2). The reduction of space allowance decreased (p < 0.05) average daily gain, feed efficiency, and digestibility of dry matter, crude protein, and gross energy. Also, the fecal score of PC groups increased (p < 0.05) compared with other groups. Basic behaviors (feed intake, standing, lying) were inactive (p < 0.05) and singularity behavior (biting) was increased (p < 0.10) under high stocking density. There was no difference in blood profile. However, the supplementation of PFA alleviated the negative effects such as reduced growth performance, nutrient digestibility, and some increasing stress indicators in th blood (cortisol) and animal behavior (biting). In conclusion, the negative effect of high stocking density was most effectively mitigated by the normal dosage of the mixture of bitter citrus extract and essential oil additive (CES1).

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.341-342
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• 2002

Although vegetable oils provide good lubricity, they still need optimization by certain additive technology for practical applications. ZDTP improve antiwear properties of vegetable oils. However the additive performance depends on quality of the base Oil. Antioxidants were applied to prevent the auto-oxidation of vegetable oils. Good synergistic effect of anti-wear and antioxidant additives was confirmed.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2769-2773
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• 2014

In this work, a new family of polyhedral oligomeric silsesquioxanes (POSS) based esters have been synthesized that consists eight ester functional groups. These are classified into Type-I and Type-II esters based on the starting materials, octakis(3-chloropropyl)silsesquioxane (Cl-POSS) and octakis(3-hydroxypropyldimethylsiloxy) octasilsesquioxane (OHPS) respectively. These new POSS type ester moieties can be used as insulating oils and oil additives in the transformers and also considered to be alternatives to mineral and vegetable oils that are presently used in the insulation system.

• Archives of Pharmacal Research
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• v.27 no.3
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• pp.351-356
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• 2004

A transdermal preparation containing diclofenac diethylammonium (DDA) was developed using an O/W microemulsion system. Of the oils tested, lauryl alcohol was chosen as the oil phase of the microemulsion, as it showed a good solubilizing capacity and excellent skin permeation rate of the drug. Pseudoternary phase diagrams were constructed to obtain the concentration range of oil, surfactant and cosurfactant for microemulsion formation, and the effect of these additives on skin permeation of DDA was evaluated with excised rat skins. The optimum formulation of the microemulsion consisted of 1.16% of DDA, 5% of lauryl alcohol, 60% of water in combination with the 34.54% of Labrasol (surfactant)/ethanol (cosurfactant) (1:2). The efficiency of formulation in the percutaneous absorption of DDA was dependent upon the contents of water and lauryl alcohol as well as Labrasol: ethanol mixing ratio. It was concluded that the percutaneous absorption of DDA from microemulsions was enhanced with increasing the lauryl alcohol and water contents, and with decreasing the Labrasol:ethanol mixing ratio in the formulation.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.163-170
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• 1999

To investigate the effect of adding sugars and lipids on characteristics of cooked rice, the solubility, swelling power, blue value, amylogram and sensory evaluation characteristics of cooked rices with 0.5, 1.0, 1.5, 2.0% level of sugars and lipids additives were measured. The solubility, swelling power and blue value of cooked rice with sugars were increased as the more sugars were added. Those parameters of the cooked rice with isomalto oligosaccharide were higher than sucrose. The solubility decreased as the more lipids were added. The swelling power decreased as the more lipids were added. As the result of amylograph analysis, addition of isomalto oligosaccharide accelerates the gelatinization and retards the retrogradation. In sensory evaluation, the cooked rice with 0.5% level of sucrose and isomalto oligosaccharide were showed better acceptability than the others. In conclusion, the additions of sugars and lipids affect characteristics of cooked rice. Especially, the cooked rice with 0.5% isomalto oligosaccharide was showed the best physiochemical and sensory properties.

• Journal of the Korean Chemical Society
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• v.19 no.1
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• pp.50-52
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• 1975

The oxidation stability of samples prepared by blending samples reported previously with diesel oil and diesel oil with additives(alkyl benzene and phenolic type of materials), was tested to study the mechanism of thermal oxidation stability of the regenerated lubricating oils. It was found that the improvement of thermal oxidation stability of such oils was caused by the formation of aromatic compounds, especially phenolic type of organic materials.