• Tribology and Lubricants
• /
• v.5 no.1
• /
• pp.51-56
• /
• 1989

The Lubricational characteristics of O/W Emulsions of beef tallow and mineral oil based lubricants are studied in a roller on disk apparatus. It is revealed that the coefficients of friction with both emulsion lubricants exhibit essentially similar behavior; that is, they rapidly decrease to 0.1% concentration and after they constants with increasing oil concentration, and that, with oil in water emulsions of a concentrations as low as 5wt% practically forms a elastohydrodynamic film. One hand, surface temperature effect on lubricants has virtually no severe, and that, the minimum EHL film chickness estimated that it begins to increase at a concentration of several percent; the effect of particle diameter becomes maked there after.

• Journal of the Korean Society of Safety
• /
• v.25 no.6
• /
• pp.81-85
• /
• 2010

In recent years, environmental concerns have been raised on the use of poorly biodegradable fluids in electrical apparatus in regions where spills from leaks and equipment failure could contaminate the surroundings. The vegetable insulation oils are highly biodegradable, have negligible effect on the environment, human health and ecosystem. Therefore, to assure their safe use in electrical power systems, it may require some processing and modification to improve some of their physical, chemical, thermal and electrical properties. This paper provides a comparative results of the electrical breakdown properties of several vegetable insulation oils and mineral oil to use as dielectric fluid in environmental-friendly pole transformer. Also, the electrical breakdown property of the Nomex and kraft insulation papers in vegetable insulation oil is examined.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.27 no.8
• /
• pp.402-408
• /
• 2015

A series of numerical simulations have been carried out to study the performances of cyclone-type oil separators, which are designed for refrigeration-system compressors. The corresponding working fluid is R22, which is a typical refrigerant, whereby a mineral-oil droplet is supplied (Ed-highlight-My interpretation). The outlet-tube length in relation to the total chamber volume is considered a design parameter. Depending on the tube length, the separation efficiency varies from 98.7% to 99.3%, while the predicted pressure drop is between 5.1 kPa and 6.4 kPa. Considering both the pressure drop and separation efficiency, the length of the outlet-port tube of the separator is 152 mm.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.15 no.1
• /
• pp.149-158
• /
• 2007

To investigate the characteristics of the nitrogen mineralization of oil cakes according to changes in temperature(10, 20, $30^{\circ}C$) moisture(40, 50, 60, 70% of field capacity in loam and 50, 60, 70, 80% of field capacity in sandy loam), mineral nitrogen was measured in soil after incubation for 30 days. In addition, the mineralization in sandy loam and loam which had different soil texture were compared. According to incubating the castor seed, soybean, and rice bran cakes with soil, the higher the temperature and moisture content were, the higher the content of mineral nitrogen was observed. The content of mineral nitrogen was higher in sandy loam than loam. The content of mineral nitrogen was decreased with soil depth increasing and was also higher in sandy loam than loam.

• Asia-Pacific Journal of Business
• /
• v.8 no.2
• /
• pp.57-73
• /
• 2017

In this paper RCA and TSI has been analyzed based on Korean and Chinese lists of export (HS 6 units) and list of companies and products with competitive advantage has been deduced. The results of RCA and TSI analysis are as follows. From the list of 20 most exported items from Korea to China the RCA index for eleven of them (based on common items from 2011-2015) is bigger than 1, thus showing comparative advantage. As for the TSI index, all of the items has shown (+) value, and has been analyzed as specialization in export. In other words, companies in the fields of mineral fuel; mineral oil; organic chemicals; electrical equipment and parts; as well as optical, precision and medical instrument are industries with competitive advantage. From the list of 20 most exported items from China to Korea the RCA index for twelve of them (based on common items form 2011-2015) is bigger than 1, thus also showing comparative advantage, and the TSI index has also shown (+) value for all of the specified items, meaning specialization in export. Industries of mineral fuel; mineral oil; iron and steel, articles of iron and steel; machinery and mechanical parts, electrical equipment and parts; as well as optical, precision and medical instruments have shown competitive advantage.

• Corrosion Science and Technology
• /
• v.7 no.6
• /
• pp.350-361
• /
• 2008

Canada's oil sands contain one of the largest reserves of oil in the world. According to recent estimates, there are nearly 180 billion barrels of oil in the Canadian oil sands trapped in a complex mixture of sand, water and clay. More than 40 companies have been currently operating or developing oil sands facilities since the first production in 1967. The process of oil sands upgrading is similar with down stream refinery, but the corrosion environment in upgrading refinery is often more severe than in the refinery because of high chlorides, mineral contents, carbonic acid, heavy viscosity and fouling, higher naphthenic acid [$NA-R(CH_{2})nCOOH$], and greater sulfur contents. Naphthenic acid corrosion (NAC) which is one of the most critical corrosion issues in up & downstream refinery plants was observed for the first time in 1920's in refinery distillation processes of Rumania, Azerbaizan (Baku), Venezuela, and California. As a first API report, the 11th annual meeting stated sources and mechanism of NAC in early 1930's. API has been developing the risk base standards, such as API RP580, 571, and Publication 581 which are based on the worst NAC damage in the world since 2000. Nevertheless not only the NAC phenomena and control in Canadian sands oil process are not much widely known but also there are still no engineering guidances for the Canadian sands oil in API standards. This paper will give NAC phenomina and materials selection guidance against NA environment in Canadian oil sands upgrading processes.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.43 no.3
• /
• pp.141-146
• /
• 1998

Production of medicinal soybean [Glycine max (L.) Merrill], characterized with black seed, white stripe at hilum border, yellow cotyledon and small seed, is increasing with increasing consumption. The objective of this study was to investigate the chemical composition of medicinal soybean seed and to provide basic information, for the characterization of these soybeans among genetic resources. Forty-four lines of medicinal soybeans collected from Korea and two control cultivars, 'Hwangkeumkong' (Yellow seed coat) and 'Geomjeongkong l' (Black seed coat) were planted at the Research Farm of the College of Natural Resources, Korea University, located at Namyangju City on May 25, 1996. Seeds of these lines were harvested at full maturity and analyzed for protein, oil, sugar, starch and mineral contents. Mean protein and oil content of the medicinal line seeds were 42.6 and 16.1%, respectively, and those of the control cultivars were in the middle range for protein and oil content. However, sugar and starch content of the medicinal line seeds appeared to be in the lower range of the distributions compared to the control cultivars and were 10.0 and 1.68%, respectively. Mean P, K, Ca, and Mg contents of the seeds of medicinal soybean lines were 15.9, 21.5, 3.11, and 2.81 mg/g, respectively, indicating that these lines had higher P, K, and Mg and lower Ca contents when compared to the control cultivars. Mean Na and Fe contents were 671 and 224 mg/kg, respectively, showing lower Na and similar Fe contents. The observed results provided that chemical compositions of medicinal soybean were, on average, different from those of the general soybean cultivars.

• Tuberculosis and Respiratory Diseases
• /
• v.41 no.6
• /
• pp.670-675
• /
• 1994

Lipoid pneumonia is a chronic inflammatory reaction of the lungs that results from the aspiration of vegetable, animal, or mineral oils. The most frequently implicated agent is mineral oil used as a laxative and to reduce dysphagia. Lipoid pneumonia is suggested when there is a history of chronic oral or intranasal use of an oil- or lipid-based product. The characteristic findings of lipid materials in CT or MRI are used in the diagnosis of lipoid pneumonia. The presence of lipid-laden macrophages in the sputum, bronchoalveolar larvage or pulmonary parenchymal biopsy confirms the diagnosis. Sputum study is simple and inexpensive. We report a case of lipoid pneumonia of 75 year old male with cough and sputum, confirmed by sputum study, and review the literature.

• Geophysics and Geophysical Exploration
• /
• v.14 no.3
• /
• pp.203-213
• /
• 2011

Time-lapse seismic surveys make repeated seismic surveys at different stages of oil production of a hydrocarbon reservoir to monitor changes in reservoir like fluid saturation. Since the repeatable surface seismic measurements can identify fluid types and map fluid saturations, oil and gas companies can make much more informed decision during not only production but also drilling and development. If time-lapse seismic surveys compare 3D seismic surveys, the time-lapse surveys are widely called as 4D seismic. A meaningful time-lapse interpretation is based on the repeatability of seismic surveys, which mainly depends on improved positioning and reduced noise (if surveys were designed properly through a feasibility study). The time-lapse interpretation can help oil and gas companies to maximize oil and gas recovery. This paper discusses about time-lapse seismic surveys mainly focused on feasibility, repeatability, data processing and interpretation.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
• /
• v.55 no.6
• /
• pp.624-634
• /
• 2018

Indonesia has become a net crude oil importer because of the reduction of a new oil field discovery, and Indonesia is attempting to raise investment funds through the Kerja Sama Operasi (KSO) contract to develop a small-scale field. However, the KSO has a high-risk and low-return contract system for investors, necessitating an economic evaluation to examine the feasibility of the project. This study performed economic evaluation on the development of an Indonesian small-scale field by applying the KSO contract conditions, and identified the major economic parameters through a sensitivity analysis. As a result, the oil price, CAPEX and OPEX were identified as influential factors for economic evaluation. The results also indicate that commercial production in small-scale fields is difficult. In the future, this study can be used as a reference resource for investment in oil and gas development projects in Indonesia.