• Asia-Pacific Journal of Business
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• v.11 no.3
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• pp.243-260
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• 2020

Purpose - This paper aims to investigate the properties of crude oil based derivative security (DLS) focusing on step-down type for comprehensive understanding of its risk. Design/methodology/approach - Kernel estimation is conducted to figure out statistical feature of the process of oil price. We simulate oil price paths based on kernel estimation results and derive probabilities of hitting the barrier and early redemption. Findings - The amount of issuance for crude oil based DLS is relatively low when base prices are below $40 while it is high when base prices are around $60 or $100, which is not consistent with kernel estimation results showing that oil futures prices tend to revert toward $46.14 and the mean-reverting speed is faster as oil price is lower. The analysis based on simulated oil price paths reveals that probability of early redemption is below 50% for DLS with high base prices and the ratio of the probability of early redemption to the probability of hitting barrier is remarkably low compared to the case for DLS with low base prices, as the chance of early redemption is deferred. Research implications or Originality - Empirical results imply that the level of the base price is a crucial factor of the risk for DLS, thus introducing a time-varying knock-in barrier, which is similar to adjust the base price, merits consideration to enhance protection for DLS investors.

• Environmental Analysis Health and Toxicology
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• v.21 no.2 s.53
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• pp.103-113
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• 2006

This study examined effects of crude oil on the phase II drug-metabolizing enzymes UDP-glucuronosyl transferase (UDPGT) and glutathione S-transferase (GST) in mussel Mytilus edulis and rockfish Sebastes schlegeli, a representative bivalve and a culture fish, respectively. This work also intended indirectly to evaluate the post impact recovery from the massive oil tanker spillage accidents occurred during the summer of 1995 in the sea area off Yosu City, Chonnam. For these, enzyme activities of UDPGT and GST were examined in the fish and mussel following laboratory exposure to fresh crude oil, weathered oil, field-obtained oil residues, or in the field biota samples. Decreased GST activity was observed in rock fish following exposure to oil-soluble fraction (OSF) of fresh oil. A similar diminished GST activity was also observed after OSF of artificially weathered oil. OSF of field oil residues retrieved from the spillage area approximately 1 year later also exerted a slight inhibition of GST to rockfish. There was neither a change in UDPGT in rockfish, nor were there changes in mussel in both enzymes to any oil fractions. We could not observe any difference in the two enzymes either in rockfish or mussel sampled from the field during $1.5{\sim}2.0$ years post spillage, indicating that their enzyme systems might had been recovered by the sampling time. In conclusion, it seems that the inhibition of GST activity in rockfish is a biomarker response to crude oil exposure. The results, however, must be interpreted with care, as the inhibition nay reflect various factors such as oil concentration, duration and water temperature.

• Korean Journal of Agricultural Science
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• v.43 no.5
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• pp.723-733
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• 2016

Soybeans [Glycine max (L.) Merill] are a rich source of antioxidants and other phytonutrients. Soybean sprouts contain many biologically active secondary metabolites and are rich in polyphenols, flavonoids, and phenolic compounds. In the present study, two soybean cultivars, Hosim, with high oleic acid (- 80% in total seed oil), and Pungsannamul, with normal oleic acid (- 23%) in seed, were examined for changes in the content of crude protein, crude oil, total flavonoids, total phenolics, and DPPH (1,1-diphenyl-2-picryl-hydrazyl) during the sprouting duration of 5 days. The protein content in both the varieties was found to increase by the days of sprouting. The crude oil content of Pungsannamul sprouts was found to be maximum on day 1 (16.9%, w/w) and decreased thereafter to reach to the level of 14.8% on day 5. No significant differences in the crude oil content of Hosim sprouts from day 1 to 5 were observed. Flavonoid content was found to increase up to day 4 and then dropped on day 5, in both the cultivars. Total polyphenol content showed a tendency to increase up to day 3 and started to decrease significantly from day 4. DPPH activity was found to increase up to day 5 in both the varieties. All the components studied in the high oleic acid soybean sprouts showed a change in content during the sprouting process similar to the change that would occur in normal oleic acid soybeans. The study showed that the contents of antioxidant, flavonoid, and polyphenol significantly increase during the sprouting.

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.375-379
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• 1998

Some Physico-chemical properties of korean red pepper seed oil were evaluated to find available method to utilize red pepper seeds used as useful cooking oil resources. Samples of red pepper seeds used as oil meterials were native, improved species and they were named such as NS (native spicies dried under sunlight), IS (improved spicies dried under sunlight), NF (native spicies dried by heating), and IF(improved spicies dried by heating), respectively. Moisture, ash, crude protein and crude fat contents of all red pepper seeds were 6.6%∼7.7%, 3.3∼3.5%, 18.25∼19.4% and 26.8∼27.5% in all samples, showing the specially high crude fat and crude protein content in NS. Capsaicin contents in crude red pepper seed oils were shown from 0.06 to 0.08% but after refining process, capsaicin contents were mostly tossed as 0∼0.006%. The types of tocopherol found in crude and refined red pepper seed oils were ${\gamma}$-, ${\alpha}$-, $\delta$-analogues, the amount of total tocopherol in IF was 2.10 mg/g oil which were the highest value of all red pepper seeds. In all red pepper seeds oils main fatty acids were linoleic acid (68∼70%), palmitic acid (14∼16%), oleic acid (10∼11%), and linolenic acid were extemely small amounts. The specific gravity (SG) 0.916∼0.919, refractive index (RI) 1.4724, acid value (AV) 0.26∼0.36, peroxide value (POV) 0.73∼1.19 and Iodine value (IV) 134.35∼134.92 were measured in all red pepper seed oils.

• Korean Chemical Engineering Research
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• v.49 no.4
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• pp.480-484
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• 2011

In this study, degumming process was carried out for reducing to less than 10 ppm of phosphorus contents and primary properties of crude canola oil including 0.64 mgKOH/g of acid value, 0.09% of water contents, 0.13% of insoluble impurities, and 40 ppm of phosphorus contents. Efficiency of water degumming and enzymatic degumming was compared for the selection of suitable process obtaining feedstock of biodiesel. Degumming method was determined for preparation of raw material of biodiesel, and reaction conditions were also established. The most effective conditions for water degumming were 2% distilled water (w/w oil), $30^{\circ}C$ of reaction temperature, 900 rpm of agitation speed, and 30 min of reaction time, respectively. In case of enzymatic degumming, optimal conditions were found to be 90 ppm of phospholipase A2 (w/w oil), $50^{\circ}C$ of reaction temperature at pH 5, respectively. When comparing water degumming with enzymatic degumming, efficiency of enzymatic degumming was better than water degumming. However, water degumming method was much more suitable for the production of biodiesel feedstock considering reaction time and process feasibility.

• Geomechanics and Engineering
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• v.20 no.4
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• pp.299-312
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• 2020

The aim of this paper was to investigating the effects of soil relative density, construction materials roughness, oil type (gasoil, crude oil, and used motor oil), and oil content on the internal and interface shear behavior of sand with different construction materials by means of a modified large direct shear test apparatus. Tests conducted on the soil-soil (S-S), soil-rough concrete (S-RC), soil-smooth concrete (S-SC), and soil-steel (S-ST) interfaces and results showed that the shear strength of S-S interface is always higher than the soil-material interfaces. Internal and interface friction angles of sand beds increased by increase in relative density and decreased by increasing oil content. The oil properties (especially viscosity) played a major role in interface friction behavior. Despite the friction angles of contaminated sands with viscous fluids drastically decreased, it compensated by the apparent cohesion and adhesion developed between the soil grains and construction materials.

• Journal of the Korean Home Economics Association
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• v.29 no.4
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• pp.37-43
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• 1991

Oxidative stability of crude wheat germ oil (WGO) was determined by the active oxygen method(Rancimat, hrs at 98$^{\circ}C$). The induction time of crude WGO was 7.6hrs as compared to 23.7hrs of crude soybean oil. However, the induction time of WGO could be extended by 2-3 times with 300ppm of mixed tocopherols and 200ppm of organic acids. The antioxidant effect of organic acids increased in the order of L-ascorbic acid > tartaric acid > citric acid > malic acid. Especially, the induction time of WGO could be extended by ca. 38hrs with 500ppm of L-ascorbic acid. This antioxiative effect of 500ppm L-ascorbic acid with mixed tocopherol(100, 200, 300 or 500ppm). It seems that the synergistic effect of L-ascorbic acid was due to the high content of tocopherols(0.4%) in WGO.

• Journal of Microbiology
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• v.37 no.3
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• pp.128-135
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• 1999

Among oil-degrading microorganisms isolated from oil-polluted industrial areas, one yeast strain showed high degradation activity of aliphatic hydrocarbons. From the analyses of 18S rRNA sequences, fatty acid, coenzyme Q system, G+C content of DNA, and biochemical characteristics, the strain was identified as Yarrowia lipolytica 180. Y. lipolytica 180 degraded 94% of aliphatic hydrocarbons in minimal salts medium containing 0.2% (v/v) of Arabian light crude oil within 3 days at 25$^{\circ}C$. Optimal growth conditions for temperature, pH, NaCl concentration, and crude oil concentration were 30$^{\circ}C$, pH 5-7, 1%, and 2% (v/v), respectively. Y. lipolytica 180 reduced surface tension when cultured on hydrocarbon substrates (1%, v/v), and the measured values of the surface tension were in the range of 51 to 57 dynes/cm. Both the cell free culture broth and cell debris of Y. lipolytica 180 were capable of emulsifying 2% (v/v) crude oil by itself. They were also capable of degrading crude oil (2%). The strain showed a cell surface hydrophobicity higher than 90%, which did not require hydrocarbon substrates for its induction. These results suggest that Y. lipolytica has high oil-degrading activity through its high emulsifying activity and cell hydrophobicity, and further indicate that the cell surface is responsible for the metabolism of aliphatic hydrocarbons.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.2057-2064
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• 2014

Thermochemical sulfate reduction (TSR) was conducted in autoclave on the system of crude oil and $MgSO_4$ at different temperatures. Gas chromatography pulsed flame photometric detector (GC-PFPD) was used to detected the composition of organic sulfur compounds in oil phase products. The results of the analysis indicate that with increased temperature, the contents of organic sulfur compounds with high molecular weight and thermal stability, such as benzothiophenes and dibenzothiophenes, gradually became dominated. In order to gain greater insight into the formation and distribution of organic sulphur compounds from TSR, positive ion electrospray Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was used in detecting the detailed elemental composition and distribution of them. The mass spectra showed that the mass range of sulfur compounds was 200-550 Da. Four sulfur class species, $S_1$, $N_1S_1$, $O_1S_1$ and $O_2S_1$, were assigned in the positive-ion spectrum. Among the identified sulfur compounds, the $S_1$ class species was dominant. The most abundant $S_1$ class species increase associated with the DBE value and carbon number increasing which also indicates the evolution of organic sulfur compounds in TSR is from the labile series to the stable one. In pure blank pyrolysis experiments with crude oil cracking without TSR, different composition and distribution of organic sulfur compounds in oil phase products were seen from mass spectra in order to evaluate their pyrolysis behaviors without $MgSO_4$. FT-IR and XRD were used in analyzing the products of solid phases. Two distinct crystallographic phases MgO and $MgSO_4$ are found to coexist in the products which demonstrated the transformation of inorganic sulfur compounds into organosulfur compounds exist in TSR.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1996.11a
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• pp.114-117
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• 1996

Biodegradation potential of crude oil has been studied in liquid and soil slurry culture. Studies were performed to optimize the factors affecting metabolic activity. Arabian Light(sulfur content 1%) was used as a representative crude oil and Nocardia sp. was selected as an oil degrading microorganism based on its ability to degrade and emulsify Effects of various nutritional and environmental conditions as well as emulsification and surface tension were observed. Tentative optimization of environmental and nutritional condition were as follow; pH 8, sodium nitrate as inorganic nitrogen source, yeast extract 0.05%, phosphate concentration 0.25% and glucose addition of 1.0% (w/v basis), extent of degradation to 78 %.