• Bulletin of the Korean Chemical Society
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• v.17 no.4
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• pp.342-347
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• 1996

Voltammetric determination of phenol derivatives, such as phenol, o-, m-, and p-cresols was studied with a β-Cyclodextrin (β-CD) modified-carbon paste electrode composing of the graphite powder and Nujol oil. Phenol derivatives were chemically deposited via the complex formation with β-CD by immersing the CME into a sample solution. The resulting surfaces were characterized with cyclic and differential pulse voltammetry. Treating the CME with 1 M nitric acid for five sec after a measurement could regenerate the electrode surface. Linear sweep and differential pulse voltammograms were recorded for the above system to optimize the experimental parameters for analysing the phenol derivatives. In this case, the detection limit for phenols was 5.0×10-7M for 25 min of the deposition time with differential pulse voltammetry. The relative standard deviation was ±5.2% of 3.0×10-6M (four repetitions). The interference effect of the following organic compounds was also investigated; Bezoic acid, hippuric acid, o-, m-, and p-methylhippuric acid. Adding the organic compounds into the sample solution reduces the peak current of the phenols to about 25%.

• Applied Chemistry for Engineering
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• v.20 no.4
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• pp.363-369
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• 2009

High oil price and biodiesel expansion lead the surplus of glycerol in the market. Glycerol has been used as a raw material itself at petroleum chemistry, paint, tobacco, household products and cosmetics in the conventional market. Recently, many research to find new applications of glycerol as a low-cost feedstock for functional derivatives have led to the introduction of a number of selective processes for converting glycerol into commercially value-added products. The recent studies on the development of new value-added glycerol derivatives will be reviewed.

• Geomechanics and Engineering
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• v.20 no.3
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• pp.207-220
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• 2020

Clay soils have a big potential to become contaminated with the oil derivatives because they cover a vast area of the earth. The oil derivatives diffusion in the soil lead to soil contamination and changes the physical and mechanical properties of the soil specially clay soils. Soil stabilization by using new material is very important for geotechnical engineers in order to improve the engineering properties of the soil. The main subjects of this research are a- to investigate the effect of the cement and epoxy resin mixtures on the stabilization and on the mechanical parameters as well as the microstructural properties of clay soils contaminated with gasoline and kerosene, b- study on the phenomenon of clay concrete development. Practical engineering indexes such as Unconfined Compressive Strength (UCS), elastic modulus, toughness, elastic and plastic strains are all obtained during the course of experiments and are used to determine the optimum amount of additives (cement and epoxy resin) to reach a practical stabilization method. Microstructural tests were also conducted on the specimens to study the changes in the nature and texture of the soil. Results obtained indicated that by adding epoxy resin to the contaminated soil specimens, the strength and deformational properties are increased from 100 to 1500 times as that of original soils. Further, the UCS of some stabilized specimens reached 40 MPa which exceeded the strength of normal concrete. It is interesting to note that, in contrast to the normal concrete, the strength and deformational properties of such stabilized specimens (including UCS, toughness and strain at failure) are simultaneously increased which further indicate on suitability and applicability of the current stabilization method. It was also observed that increasing cement additive to the soil has negligible effect on the contaminated soils stabilized by epoxy resin. In addition, the epoxy resin showed a very good and satisfactory workability for the weakest and the most sensitive soils contaminated with oil derivatives.

• Advances in nano research
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• v.15 no.6
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• pp.541-550
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• 2023

The escalating growth of industrial sectors has led to a pervasive global problem—oil pollution, particularly in industrial areas. The release of substantial volumes of oil and its by-products into the environment has resulted in extensive contamination. Multiple factors contribute to the entry of these substances into water bodies and soils, thereby inflicting irreparable consequences on ecosystems, natural resources, and human health. Consequently, it becomes imperative to comprehend the characteristics and behavior of oil pollution, anticipate its impacts, and develop effective mitigation strategies. Understanding this intricate issue requires considering the physicochemical properties of the environment, the interactions between oil and sediments, and biological factors such as evaporation and dissolution. Although the oil industry has brought about remarkable advancements, its activities have raised significant concerns regarding pollution from extraction and production processes. Oil-rich nations face a particularly challenging predicament of soil pollution caused by petroleum compounds. The areas surrounding oil exploration mines and refineries often endure contamination due to oil leakages from storage tanks and transmission lines resulting from deterioration and damage. Investigating the dispersion of such pollutants and devising methods to remediate petroleum-contaminated soil represent crucial and intricate issues within the realm of environmental geotechnics.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.31-56
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• 1993

The characteristic aroma of Gardenia Absolute Oil made from Gardenia Jasminoides Ellis was investigated by GC and GC-MSD and by sensory evaluation The method of GC Analysis was used Double Column System by Carbowax 20M /SPB-1 of Pola/nonPola columns. And the result data of analysis was checked automatic Relent ion Indexs Match System by GC Workstation. A total of 51 compounds were identified in Gardenia Absolute Oil, including t entatively erstimated 9 compounds. The major components were Linalool, Farnesene of various form, Jasmin Lactone, Gamma undecalactone and Cis-3-hexone derivatives.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.2
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• pp.171-176
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• 2011

N-feruloylserotonin (FS) and N-(pcoumaroyl) serotonin (CS), serotonin derivatives, which have been isolated as major and unique phenolics of safflower seed extract (SSE), are member of hydroxycinnamic acid amides and are implicated in the defense against pathogen infection and insect feeding. In this study, we evaluate inhibitory effects of N-(p-Coumaroyl)serotonin and N-Feruloylserotonin on adipogenesis using oil-red O staining, triglyceride and GPDH activity. we found that while serotonin itself did not suppress differentiation of preadipocytes into adipocytes, N-(p-Coumaroyl)serotonin and N-Feruloylserotonin inhibited the differentiation of preadipocytes into adipocytes in a concentration-dependent manner. In addition, they showed antioxidant effects in DPPH assay. Taken together, these results show that N-feruloylserotonin (FS) and N-(pcoumaroyl) serotonin (CS) suppress differentiation of preadipocytes, suggesting the possibility that these serotonin derivatives can be utilized as an anti-obesity agent.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.323-329
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• 2004

The electrical and rheological properties pertaining to the electrorheological (ER) behavior of chitosan derivatives, chitosan, chitosan ammonium salt and chitosan phosphate suspensions in silicone oil were investigated. Chitosan derivative suspensions showed a typical ER response (Bingham flow behavior) upon application of an electric field. However, chitosan phosphate suspension exhibited an excellent shear yield stress compared with chitosan and chitosan ammonium salt suspensions. The difference in behavior results from the difference in the conductivity of the disperse phases due to the difference of their polarizability. The shear stress for the chitosan, chitosan ammonium salt and chitosan phosphate suspensions exhibited a linear dependence on the volume fraction of particles and 1.18 ,1.41 and 1.67 powers of the electric field. On the basis of the experimental results, the newly synthesized chitosan derivative suspensions found to be an ER fluid.

• Journal of ILASS-Korea
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• v.14 no.4
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• pp.153-162
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• 2009

The use of inedible vegetable oils as substitute for diesel fuel in compression ignition engine is of significance because of the great need for edible oil as food, and the reduction of biodiesel production cost etc. Jatropha curcas oil which is a leading candidate for the commercialization of inedible vegetable oils is selected in this study for reviewing the application in CI engine as an alternative fuel. The important properties of jatropha oil (JO) and JO biodiesel are summarized from the various sources in the literature. It is found that five different types of alternative fuel from JO such as neat JO, JO blends with diesel or other fuel, neat JO biodiesel, JO biodiesel blends with diesel or other fuel and degummed JO were extensively examined in the diesel engine. Two different application types of alternative fuels from JO such as preheating and dual fuelling were also tested, It should be pointed out that most of these applications are limited to single cylinder conditions. The systematic study for the selection of effective application method is required. It is clear that the blends of JOME and diesel can replace diesel fuel up to 10% by volume for running the existing common rail direct injection systems without any durability problems. The systematic assessment of spray characteristics of different types of JO and its derivatives for use as diesel engine fuel is also required.

• The Korean Journal of Food And Nutrition
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• v.31 no.3
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• pp.378-387
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• 2018

This study investigated the volatile flavor composition of essential oils from Chrysanthemum zawadskii var. latilobum Kitamura and Aster yomena Makino. The essential oils obtained by the hydrodistillation extraction method from the aerial parts of the plants were analyzed by gas chromatography (GC) and GC-mass spectrometry (GC-MS). One hundred (95.04%) volatile flavor compounds were identified in the essential oil from the C. zawadskii var. latilobum Kitamura. The major compounds were valencene (10.82%), ${\delta}$-cadinol (9.77%), hexadecanoic acid (8.70%), 2-methyl-4-(2,6,6-trimethylcyclohex-1-enyl) but-2-en-1-ol (3.67%), and 2-(2,4-hexadiynylidene)-1,6-dioxaspiro[4,4]non-3-ene (3.57%). Ninety-eight (93.83%) volatile flavor compounds were identified in the essential oil from the Aster yomena Makino. The major compounds were and 3-eicosyne (13.61%), 9,10,12-octadecatrienoic acid (7.8%), ${\alpha}$-caryophyllene alcohol (6.83%), 9-octadecynoic acid (6.03%), and ${\alpha}$-caryophyllene (5.74%). Although the two plants are apparently very similar, the chemical composition of the essential oils was significantly different in quality and quantity. In the case of C. zawadskii var. latilobum Kitamura, the sesquiterpene, valencene was found to be 10.82%, but it was not identified in A. yomena Makino. ${\delta}$-Cadinol appeared higher in C. zawadskii var. latilobum Kitamura than in A. yomena Makino. A clear characteristic of A. yomena Makino essential oil is that it has a high content of caryophyllene derivatives. The ${\alpha}$-caryophyllene alcohol contained in A. yomena Makino was relatively high at 6.83%, although the compound was not identified in C. zawadskii var. latilobum Kitamura. Also ${\alpha}$-caryophyllene was shown to be higher in A. yomena Makino than in C. zawadskii var. latilobum Kitamura.

• Environmental and Resource Economics Review
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• v.18 no.1
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• pp.139-158
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• 2009

With the sample of Middle East crude oil imported to South Korea, this study empirically analyzes the effectiveness of the risk management strategies using derivatives such as futures and options. Assuming the hedging period of one to twelve months, it considers a spot purchasing strategy, 1 : 1 futures hedge strategy, OLS-based minimum-variance futures hedge strategy, buying call option strategy, and collar transaction strategy. According to the ex-ante result, using the derivatives of futures or options makes lower the procurement costs when the crude oil prices is increasing. With the hedging period less than or equal to six months, the hedging strategy using futures turns out to be superior in terms of procurement cost reduction and hedging effectiveness improvement. In contrast, the hedging strategies of buying call option and collar transaction would generate better results when the hedging program last over six months.