• Korean Chemical Engineering Research
• /
• v.43 no.4
• /
• pp.511-516
• /
• 2005

In this work, the crosslinked-chitosan microcapsules containing fragrant oil were prepared by oil-in-water-in-oil (O/W/O) multi-emulsion method. The effects of concentration of fragrant oil and stirring rates on the preparing of the microcapsules were investigated. The diameter and form of the microcapsules were observed by scanning electron microscope (SEM). As a result, the average particle size of microcapsules was decreased with increasing the stirring rate. The formation of chitosan microcapsules was comfirmed by FT-IR. The inclusion of fragrant oil into chitosan microcapsules was determined in the presence of specific peak of fragrant oil, i.e., $1,460cm^{-1}$, $2,960cm^{-1}$. Also, the release behavior or profile of fragrant oil from chitosan microcapsules was examined with UV/vis spectra. Released amounts of fragrant oil were increased with increasing as the content of fragrant oil and decreasing the pH.

• Korean Journal of Food Science and Technology
• /
• v.30 no.4
• /
• pp.739-744
• /
• 1998

Changes of volatile flavor compounds in sesame oil during industrial process (roasting temp. $225{\pm}2^{\circ}C$, roasting time 15 min) were investigated. Total volatile flavor compounds of 1 st expressed oil from roasted sesame seeds were 536.3 ppm, and those of 2nd expressed oil from sesame seed cake, residue of 1st expression, were 266.8 ppm. Those of 1st filtered oil, fixed oil and 2nd filtered oil were 472.2 ppm, 472.4 ppm and 443.0 ppm, respectively. Volatile flavor compounds were gradually decreased during processing. Top notes $(peak{\;}No.1{\sim}26)$ playing an important role in the aromatic character of sesame oil, of 2nd expressed oil were markedly reduced (70.67% of initial content). Especially pyrazine compounds showed the largest reduction in 2nd expressed oil. Total volatile flavor compounds of fixed oil, filtered oil were reduced slightly.

• Journal of the Korean Society of Food Culture
• /
• v.36 no.3
• /
• pp.317-324
• /
• 2021

This study was carried out to investigate the flavoral essential oil components in the stems of Agastache rugosa. These components were analyzed using gas chromatography-mass selective detector (GC-MSD). The stems of Agastache rugosa were contained alcohols, aldehydes, ketones, fatty acid esters, and terpenoids. The peak area (%) of estragole was highest among its oil components and the next were pulegone and menthone. The terpenoid alcohols found were 1-octen-3-ol, chavicol, spatulenol, 3-hexen-1-ol, 2-cyclohexen-1-ol, methyl eugenol, and octaethyllene glycol. The stems also contained ketones such as pulegone, menthone, cis-isopulegone, 2-cyclohexene-1-one, 3-octanone, 1-cyclohexanone, isoindole-1-one, t-ionone, inden-2-one, as well as the aldehydes of 4-methoxycinnam and benzaldehyde. The following esters were also detected 1-isopulegone-3-yl acetate, caryophyllene oxide, acetate and benzendicarboxylic acid ester. The terpenoids in the stems were identified as caryophyllene, limonene, cyclohexasiloxane-D, germacrene-D, anethole, cadinene, muurolene, and bourbonene. Overall Agastache rugosa contained several functional oil components including phenylpropanoids and terpenoids as flavoral essential oil components for natural aromatherapy.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.40 no.12
• /
• pp.1734-1742
• /
• 2011

Conjugated linolenic acid (CLnA) and conjugated linoleic acid (CLA) are positional geometric isomers with three and two double bonds, respectively. In this study, perilla seed oil containing 60% ${\alpha}$-linolenic acid (C18:3) and 30% linoleic acid (C18:2) was used as a reaction substrate. After the perilla seed oil was hydrolyzed, conjugated fatty acids were synthesized using different reaction parameters, such as reaction time and concentration of sodium hydroxide. As a result, CLnA, CLA, and other newly synthesized conjugated isomers were present at levels of 14.5%, 14%, and 42.2%, respectively, when the reaction was performed with 20% NaOH, at $180^{\circ}C$, and for 1 hr. The results of GC-MS and fourier transform infrared spectroscopy (FT-IR) showed that CLnA isomer of cis-9, trans-11, and trans-13 octadecatrienoate, CLA isomer of cis-9, trans-11, and trans-10, cis-12 octadecadienoate, and other conjugated isomers were produced. Using urea, ${\alpha}$-linolenic acid could be concentrated from perilla seed oil hydrolysate. After concentration by urea, the concentration of ${\alpha}$-linolenic acid reached about 70%. After alkaline-isomerization was performed on the urea fraction containing 70% ${\alpha}$-linolenic acid, the content of CLnA increased up to 16.6%.

• Analytical Science and Technology
• /
• v.25 no.4
• /
• pp.207-213
• /
• 2012

Analysis of the aroma constituents present in the rose essential oil of Chinese Kushui type (Rosa sertata ${\times}$ Rosa rugosa) by GC-FID and GC-MS was performed independently as an expert for the inter-laboratory round-robin test to verify reproducibility according to the decision of the preliminary meeting of ISO/TC-54 (Shanghai, Sep. 14-15, 2010). Total 179 peaks (using SPB-1 apolar column), 165 peaks (using DB-624 intermediate polar column), and 162 peaks (using Supelcowax-10 polar column) were separated by GC-FID, respectively. Major constituents (over 5%) by GC-FID were ${\beta}$-citronellol (41.6~46.7%), geraniol (9.7~11.0%), and nerol (3.4~4.5%). ${\beta}$-Citronellol peak was overlapped with nerol peak on SPB-1 and DB-624 columns, whereas the two peaks were separated each other on Supelcowax-10 column. Our results were generally consistent with Chinese data (ISO/DIS 25175); however, a peak of phenethyl alcohol separated by using PEG (Supelco wax) column was found at the quite different retention time. Comparative analysis was conducted using Bulgarian rose (Rosa damascena Miller) oil and perfume. Bulgarian rose oil showed rich amounts of characteristic aroma constituents than the essential oil of Chinese Kushui type.

• KSBB Journal
• /
• v.10 no.5
• /
• pp.582-588
• /
• 1995

A marine microorganism producing biosurfactant was isolated from the oil polluted coast of Chung-Mu in Korea, and was identified as Pseudomonas sp.. It produced the biosurfactanl and its optimum culture conditions for pH and salt concentration were 8.0 and 3.0%, respectively. The productivity of biosurfactant from this strain was affected by the nitrogen source used. For the oil resolvability of the biosurfactant, the residual oil in the culture broth with 2% Kuwait crude oil at each time of 48, 96, and 132hr was investigated by gas chromatography. As result of this experiment, it was verified that the biosurfactant acted on C10-C14, of Kuwait crude oil and so the oil was decomposed. The biosurfactant isolated from the supernatant was purified by adsorption to Amberliter XAD-7 and followed by gel chromatography (Sephadex G-100) and HPLC. The purified biosurfactant showed a high value of emulsifying activity at $40^{\circ}C$ and the emulsifying stability was maintained at the temperature range of $30^{\circ}C$∼$60^{\circ}C$. The purified biosurfactant reduced the interfacial tension of Kuwait crude oil remarkably and showed improved dispersing ability compared to those of commercial surfactants such as Tween 80, Tween 60 and SDS.

• Fire Science and Engineering
• /
• v.29 no.3
• /
• pp.31-36
• /
• 2015

This study analyzed the flame characteristics when igniting 200 ml of flammable liquids containing equal parts gasoline and another flammable liquid. These mixtures were used to fill a divided space in a simulation. The length of one side of the divided space was 2,000 mm, and the length of the combustion device was 1,000 mm. The mixture with alcohol had the highest flame propagation speed (0.7 s), while the mixture with light oil showed the lowest (1.2 s). The gasoline and acetone mixture reached peak flame in 25.5 s, at the highest speed, while the mixture with light oil reached peak flame in 163.7 s at the lowest speed. The gasoline and light oil showed the longest continuous combustion time (332.7 s), while the gasoline and paint thinner showed the shortest (121.5 s). A fire inspector who is examining the scene of a fire needs to analyze both the statements of the first eyewitness and the flame characteristics collectively.

• Applied Biological Chemistry
• /
• v.2
• /
• pp.36-39
• /
• 1961

It has been ascertained that S-(1, 2-dichlorovinyl) L-cysteine (DCVC) is probably the toxic component in the trichloro-ethylene extracted soybean oil meal on the bovine. For the study of the metabolites of DCVC, the components with radioactive $S^{35}$-in the urine of the calf, to which $S^{35}$-DCVC was administrated, were separated using of cellulose powder with propanol-water (70:30 V/V) which is easily removable by evaporation. As the results followings were obtained: Peak 1, which shows fractions containing single $S^{35}$-radioactive components, whose Rf is 0.815 Peak 2, which shows fractions containing jingle $S^{35}$-radioactive component, whose Rf is 0.447 Peak 3, which shows fractions containing both $S^{35}$-radioactive components whose Rfs are 0.090 and 0.171 Peak 4, which shows fractions containing single $S^{35}$-radioactive component, whose Rf is 0.142. Peak 5, which shows fractions containing single $S^{35}$-radioactive component, whose Rf is 0.084. Besides these, two of small peak were obtained. Although, the resolving power of the cellulose powder column is not sufficient, it is applicable for the study of the components of metabolytes of DCVC conveniently with the rest of removable solvent easily. Also the components with radioactive $S^{35}$ in the feces of the calf were separated using citrate buffer gradient system of Moore and stein. As the results; three $S^{35}$-radioactive components were separated.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.20 no.10
• /
• pp.907-911
• /
• 2007

This paper dealt with the frequency spectrum analysis of acoustic signal produced by partial discharge (PD) in insulation oil and the positioning of PD occurrence to apply in diagnosis of oil insulated transformers. Three types of electrode system ; the needle-plane, the plane-plane, and the wire-wire structure were assembled to simulate partial discharges in oil insulated transformers. A low-noise amplifier and a decoupling circuit were designed to detect acoustic signal with high sensitivity The frequency spectrum of the acoustic signal were 50 kHz ${\sim}$ 260 kHz in the needle-plane, 50 kHz ${\sim}$ 250 kHz in the plane-plane, and 45 kHz${\sim}$195 kHz in the wire-wire electrode system. Their peak frequencies were 145 kHz, 130 kHz and 114 kHz, respectively The position of PD occurrence was calculated by the time difference of arrival (TOA) using three acoustic emission (AE) sensors, and we could find the position within the error of 1 % in the experimental apparatus.

• Structural Engineering and Mechanics
• /
• v.17 no.2
• /
• pp.187-201
• /
• 2004

A shaking table test on a three-story one-bay steel frame model with metallic yield dampers and their parallel connection with oil dampers is carried out to study the dynamic characteristics and seismic performance of the energy dissipation system. It is found from the test that the combined energy dissipation system has favorable reducing vibration effects on structural displacement, and the structural peak acceleration can not evidently be reduced under small intensity seismic excitations, but in most cases the vibration reduction effect is very good under large intensity seismic excitations. Test results also show that stiffness of the energy dissipation devices should match their damping. Dynamic analysis method and mechanics models of these two dampers are proposed. In the analysis method, the force-displacement relationship of the metallic yield damper is represented by an elastic perfectly plastic model, and the behavior of the oil damper is simulated by a velocity and displacement relative model in which the contributions of the oil damper to the damping force and stiffness of the system are considered. Validity of the analytical model and the method is verified through comparison between the results of the shaking table test and numerical analysis.