• Tribology and Lubricants
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• v.18 no.4
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• pp.273-278
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• 2002

Grease deterioration of mineral oil type grease was investigated using sealed deep groove ball bearings (6203) and bearing life test rig. The bearing test was performed under 3,000 rpm and 245 N radial load at 120。C. Grease taken ken tested bearings was checked in using certain evaluation methods, for example, oxidation induction time (OIT), FT-IR peak intensity, leakage .ate, bleeding .ate, total acid number. (TAN) and bearing noise increase. Within these test conditions, OIT, TAN, bleeding rate were changed gradually in accordance with bearing operating time and showed useful indices for deterioration of grease.

• Journal of Industrial Technology
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• v.10
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• pp.83-88
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• 1990

The samples used for this work were low grade c1ay($Fe_2O_3$ : 2.90%, $TiO_2$ : 1.65%) produced from Youngsan-po district, and for the iron-bearing impurities removal having a bad influence on Kaoline sample was carried out column floatatoin using Oleic acid, Potassium oleat, Aero 840 promotor, Aero 870 promotor and Keroseneas collectors. For removal of the iron-vearing impurities from the kaoline, investigated first chemical composition size distribution of Kaoline sample, also performanced a basic study on pulp density, collector and pH change on a sort of frother. The flotation separation of impurities from kaoline can be achieved by using both oleic acid and Aero 840 promotor as collectors within narrow acid limits(pH 2-3). Pine oil was more effective frother than MIBC with olelic acid as aa collector.

• Journal of the Korean Applied Science and Technology
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• v.23 no.3
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• pp.192-198
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• 2006

To provide an aqueous rust inhibitor for metalworking lubricant having low toxicity and excellent rust resistance, we synthesized diester of malonic acid by three consecutive esterifications with over 98% of conversion. This substituted malonic diester could be used as an additive to mineral oil based metalworking lubricant. These metalworking lubricant compositions were showed excellent rust resistance and suitable for various metals and different metalworking processes including hot rolling and cold rolling of aluminum and aluminum alloys.

• Tribology and Lubricants
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• v.16 no.1
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• pp.22-26
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• 2000

In this paper, the fuction of Zinc-dialkyldithiophosphate (ZnDTP) as an oxidation ingibitor of mineral oils was investigated and compared with 2,6-Di-tert-Butyl-4-Methylphenol (DBMP). Oxidation tests were conducted using an oxygen absorption apparatus. ZnDTP showedanti-oxidation property, and length of induction period prolonged by increasing ZnDTP concentration. The anti-oxidation property of ZnDTP was simmilar to that with DBMP. The amount of hydroperoxide decomposition ability with ZnDTP was much greater than that with DBMP, But the rate constant of radical scavenging with ZnDTP was less than that with DBMP. The anti-oxidation property of ZnDTP seems to by both synergy effect of hydroperoxide decomposition ability and radical scavenging ability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.886-889
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• 2002

This paper describes the characteristic analyses and a new design of the bushing for the pole transformers. The mechanical breakdown of the upper part of the bushing was frequently occurred. This caused the leakage of mineral oil, resulted in the interruption of electric power. Therefore, the bushings were investigated by the material analytical method and Finite Element Method. The analyses were performed by the Induced Coupled Plasma(ICP), X-ray diffraction(XRD), Scanning Electron Microscopy(SEM), and Dielectric Thermal Analyzer(DETA). Also, the Von-Mises stress of the top part of bushing was determined by using ANSYS program. The Von-Mises stress of the newly designed bushing was reduced about 50%. Therefore, if we apply the newly designed bushing, the number of mechanical breakdown may be decreased.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.132-133
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• 2005

A study to evaluate the fire extinguishing performance of the water mist system inside simulated machinery spaces according to IMO MSC/Circ.668 was performed. Fire tests were conducted inside a compartment having a area 100$m^2$(10m${\times}$10m) with a ceiling height of 10m and door opening of 2m${\times}$2m in size. Test fuels were used heptane, diesel, wood crib and mineral oil. Water mist nozzles were installed downward at ceiling and horizontally at bilge area. All fires in the test were extinguished within 15minutes of system activation and there was no reignition or fire spread.

• Journal of the Korean Chemical Society
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• v.21 no.5
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• pp.384-388
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• 1977

Clay-polymer thickened greases were made by dispersing bentone-polyethylene and bentone-atactic polypropylene into mineral oil at an adequate temperature, and the physical properties such as wear and water washout characteristics, oxidation and shear stabilities, and dropping point of the greases were tested. Even if the greases failed to meet some properties, it was found that those greases can be used for some special purposes, by observing and comparing the properties with those of clay-metallic soap thickened greases that were made in this experiment.

• Tribology and Lubricants
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• v.17 no.3
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• pp.171-178
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• 2001

In order to elucidate the lubricating mechanism of polyolester base oils [POEs], the wear characteristics of 27 kinds of polyolester base oils including mixed POEs were investigated. Their wear results were discussed in terms of the effect of molecular structure on wear performance and compared with those of mineral oil. In addition, the adsorption ability of POEs to reduced iron and their hydrolysis rates were measured and the effect of their molecular structures on the adsorptivity and hydrolysis rate of POEs was discussed, respectively. Finally, the lubricating mechanism anlyzed from these results of wear characteristics, adsorptivity and hydrolysis rate was proposed. That is to say, POEs are firstly adsorbed to friction surface and decomposed by hydrolysis or thermal degradation. Fatty acids obtained by degradation of POEs form adsorption film on friction surface. The larger become cohesive ability among fatty acid molecules in the adsorption film, the better gets the wear performance of POEs.

• Proceedings of the KIEE Conference
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• 2004.11d
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• pp.89-92
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• 2004

This paper described the capacitive sensor for the diagnosis of deterioration of electrical insulating oils applying guard-ring type the 3-terminal electrodes. To measure stable capacitance of the sensor and to determine the design factors of the sensor, we utilized computational analysis, FEM software. This capacitive sensor discern the extent of deterioration measuring relative permittivity of electrical insulating oils. The result of measuring numerous sample, mineral oils, as serviced year, we confirmed an increase in relative permittivity of oils. Moreover, we confirmed the superior characteristics of the sensor as a species, aged pattern of oils and operating temperature.

• The Korea Journal of Herbology
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• v.20 no.2
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• pp.181-191
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• 2005

Objectives : This research examined about dietary therapy on the constipation based on the literary findings, for clinical treatment and prevention of the constipation. Methods : This Research examined on histories, compositions, applications, and effects of the constipation on about 100 cases of dietary therapy of the constipation from recent Chinese literatures Results : 1. Various vegetables, animals and mineral materials including herbs, grains, vegetables, fruits, food and drink were used for the dietary therapy. 2. Methods of the preparation for use as therapeutics were decoction, pulvis, gruel, medicinal wine, cake, tea, paste and gelatin and etc. 3. Frequently used materials were sesame oil, honey, ear mushroom, shiitake mushroom, kelp, walnut seed, hemp seed, groundnut, glutinous rice, apricot stone, yellow bean peel, radish, potato, spinage, and spring onion. Conclusion : Though dietary therapy for the constipation is not based on clinical or experimental data, but through experience. It is mostly based on Yin-Yang and five elements, visceral manifestation, channels and their collateral channels and chinese herbal medicine theories. If we use them properly according to oriental medicine method, it will be effective on treating and preventing the constipation.