• Journal of Korean Society for Atmospheric Environment
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• v.14 no.2
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• pp.95-106
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• 1998

Volatile organic compounds (VOCs) from Ca to C9 were investigated with nine ambient air samples collected in April 26, August 17, 1996 and January 23, 1997 in a Seoul site. On each sampling day, three 2-hr integrated canister samples were collected in early morning, early afternoon and late afternoon, respectively to study temporal . variation of VOCs. Most of VOC species showed diurnal variation with higher concentrations in the early morning and lower concentrations in the afternoon. The concentrations of light alkanes were high, probably due to the emission from liquefied petroleum gas (LPG) and evaporation of gasoline. Especially, the concentration of propane was the highest in the morning samples. The concentrations of propane, ethylene, acetylene, and toluene were prominent in their hydrocarbon groups, respectively. These components were the main source of car exhaust, gasoline evaporization, LPG, or solvent usage.

• Journal of the Korean Applied Science and Technology
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• v.24 no.1
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• pp.47-53
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• 2007

The acenaphthene(ACE) or acenaphthylene(ACEL) is one of the most frequently found compound in polycyclic aromatic hydrocarbon (PAH)-contaminated soil. In this study, we make 10mg/L ACE or ACEL in ethanol which is the model washing solvent for contaminated soil. This was followed by Fenton treatment in which 0.2 or 0.3mL of 30% $H_2O_2$ and 0.2 ml of 0.5 M $Fe^{2+}$ were added. The results showed more than 88 or 99% of ACE or ACEL removal efficiency, respectively. Additionally, we employed GC-MS to identify the main oxidation product generated by the optimized Fenton oxidation [i.e., ACE or ACEL degraded in to 21, 34 % 1,8-naphthalic anhydride(NAPAN), repectively]. It is expected that biodegradability of NAPAN is enhanced because NAPAN has three oxygens compared with ACE and ACEL. Therefore the results suggest that the hybrid treatment system (i.e., ethanol washing -Fenton oxidation treatment) can be effectively applied to remove ACE or ACEL from soil..

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.2
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• pp.319-325
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• 1999

Volatile flavor compounds in Korean salt fermented shrimp on the market were analyzed by vacuum simultaneous distillation solvent extraction/gas chromatography/mass spectrometry/olfac tometry(V SDE/GC/MS/O) and aroma extract dilution anlaysis(AEDA). A total of 32 volatile com pounds were detected by GC/O analysis. Of these, 18 were positively identified, and composed of S containing compounds(5), aldehydes(4), ketones(3), N containing compounds(3), ester(1), alcohol(1) and aromatic hydrocarbon(1). Predominant odorants(Log3FD$\geq$4) in salt fermented shrimp were 2,3 butanedione(sour/buttery), 1 octen 3 one(earthy/mushroom like), dimethyl trisulfide(cooked cabbage /soy sauce like) and 2 acetylthiazole(grainy/nutty). Predominant free amino acids were aspartic acid, glutamic acid(sour and umami taste), arginine, methionine(bitter) and lysine(sweet and bitter) in evaluation of taste value.

• Preventive Nutrition and Food Science
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• v.11 no.3
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• pp.232-236
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• 2006

The essential oil of Swertia chirata Buch.-Ham. was extracted by solvent extraction (n-pentane:diethylether, 1:1) method using simultaneous distillation-extraction (SDE) apparatus and analyzed by gas chromatography-mass spectrometry (GC/MS). The yield of essential oil obtained from S. chirata was 236.47 mg/kg. Seventy seven compounds of the essential oil belonging to chemical classes of acid (4), alcohol (21), aldehyde (15), ester (3), furan (3), hydrocarbon (7), ketone (17) and miscellaneous (7) were tentatively identified. The major volatile compounds ranged in content order were as follows: undecanoic acid (28.63%), 2-buten-2-one (20.42%), camphor (18.40%), 2-heptadecanone (14.72%), and cedrol (13.07%).

• Journal of Adhesion and Interface
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• v.7 no.2
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• pp.12-18
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• 2006

Recently, as industries and technologies are increased, superior adhesives having more and more developed functions and properties have been demanded. In this article, to use the merits and viscoelastic properties of poly(ethylene/butylene) rubber resin and to supplement the demerits, semi-structure pressure sensitive adhesives (PSAs) are developed. Aslo, it can be said environmentally friendly PSAs because of not use the organic solvent and not emit volatile organic compounds (VOCs).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.10
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• pp.1-7
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• 2020

In this study, a multichannel gas-liquid microextraction system is designed by integrating the automatic elution of extraction line and multichannel gas-purging liquid phase microextraction. The system uses an injection pump and inert gas to push the extraction solvent to a sample bottle of a gas-phase color autosampler and then implements multichannel gas-liquid microextraction and gas chromatography-mass spectrometry. The system also employs a three-way integrated micro-high-temperature heater, syringe pump, and microflow controller to realize the simultaneous processing of multiple groups of samples, thus improving the sample pretreatment speed and reproducibility and reducing human error. Autoinjection experiments were implemented with polycyclic aromatic hydrocarbon standard samples. The experiments show that the average recovery rate of the system exceeds 70%, and the relative standard among the channels is less than 15%.

• Clean Technology
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• v.26 no.4
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• pp.279-285
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• 2020

Laboratories and industrial processes typically involve the use of flammable substances. An important property used to estimate fire and explosion risk for a flammable liquid is the flash point. In this study, flash point data at 101.3 kPa were determined using a SETA closed cup flash point tester on the following solvent mixtures: {2,2,4-trimethylpentane + methylcyclohexane}, {2,2,4-trimethylpentane + ethylbenzene}, and {2,2,4-trimethylpentane + p-xylene}. The purpose of this work is to obtain flash point data for binary mixtures of 2,2,4-trimethylpentane with three hydrocarbons (methylcyclohexane, ethylbenzene, and p-xylene), which are representative compounds of the main aromatic hydrocarbon fractions of petroleum. The measured flash points are compared with the predicted values calculated using the GE models' activity coefficient patterns: the Wilson, the Non-Random Two-Liquid (NRTL), and the UNIversal QUAsiChemical (UNIQUAC) models. The non-ideality of the mixture is also considered. The average absolute deviation between the predicted and measured lower flash point s is less than 1.99 K, except when Raoult's law is calculated. In addition, the minimum flash point behavior is not observed in any of the three binary systems. This work's predicted results can be applied to design safe petrochemical processes, such as identifying safe storage conditions for non-ideal solutions containing volatile components.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.641-647
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• 1997

Volatile flavor components in whole edible portion, stem and leaf of fresh angelica (Angelica keiskei Koidz) were extracted by SDE (simultaneous steam distillation and extraction) method using the mixture of n-pentane and diethylether (1:1, v/v) as an extract solvent and analyzed by GC-FID and GC/MS. Identification of the volatile flavor components in aroma concentrate was mostly based on the RI of GC and mass spectrum of GC/MS. Twenty five hydrocarbons, 15 alcohols, 3 aldehydes, 6 esters, 2 ketones and 1 acid were identified in the whole edible portion of angelica. Twenty hydrocarbons, 13 alcohols, 4 esters and 1 acid were identified in the stem sample of angelica. Nineteen hydrocarbons, 11 alcohols, 4 aldehydes, 6 esters, 2 ketones and 1 acid were identified in the leaf sample of angelica. ${\gamma}-Terpinene$, germacrene B, ${\delta}-3-carene$, cis-3-hexen-1-ol, ${\gamma}-muurolene$ and ${\gamma}-elemene$ were the main components in each edible portions of angelica. The terpenoid compounds in volatile flavor components identified from whole edible portion, stem and leaf samples were confirmed as 75.76%, 86.42% and 78.21%, respectively. These results suggest that terpenoid compounds have a great effect on the flavor characteristics of angelica.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1615-1621
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• 2008

The characteristics of volatile flavor compounds of Fuji apples were compared by different extraction methods for information leading to a natural fragrance development. The volatile flavor components of Fuji apples were extracted using simultaneous steam distillation and extraction (SDE), solvent extraction (SE), and solid-phase microextraction (SPME) methods and then analyzed by gas chromatograph-mass spectrometer. A total of 66, 32 and 54 components were identified in SDE, SE and SPME extracts, respectively. (E,E)-$\alpha$-Farnesene, hexanol, butanol, 2-methyl butanol, hexyl hexanoate, hexyl 2-methyl butanoate, hexyl butanoate, and butyl hexanoate were the major flavor components in the extracts by different methods, but the composition of volatiles in the extracts were different. Alcohols and hydrocarbons were the major functional groups in SDE and SE extract whereas esters and hydrocarbons were the major functional groups in SPME extracts. SPME was the most suitable method for analysis of fresh volatiles from Fuji apples.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.1
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• pp.27-32
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• 2003

To understand the chemical structure of sewer sludge in comparison with commercial compost and charcoal used as a soil improver, it was carried out to analyse their ash contents and metal ions, and to elucidate the chemical structure of their residuals after a sequential treatment of alcohol-benzene(1:2) extraction in Soxhlet, 3% HCl reflux and 79% H₂SO₄ hydrolysis, using CHNS analyzer and solid C-13 NMR spectrometer. The results obtained were as follows: 1. Ash content of sludge was about 46% that is higher than those of compost (17%) and charcoal (4%). 2. The residual of sludge after a sequential treatment of HCl and H₂SO₄ hydrolyses had high ash content about 23%, too. 3. The sludge seems to be suitable to the soil improver because the content of heavy metal ions in sludge was near the compost and below the organic fertilizer standard. 4. Elemental composition of sludge residual after HCl-H₂SO₄ hydrolyes was C/sub 56/H/sub 91/O/sub 12/N₂S = (C/sub 6/H/sub 10/O/sub 5/)/sub 7/(C/sub 6/H₄)/sub 7/C₂H/sub 43/O₂N₂S, similar to C/sub 103/H/sub 122/O/sub 33/N/sub 6/S = (C/sub 6/H/sub 10/O/sub 5/)/sub 6/(C/sub 6/H₄)/sub 10/C/sub 7/H/sub 22/O₃N/sub 6/S of compost. 5. The sludge residual had proved to have both considerable aliphatic and aromatic groups, but the compost residual to have mainly aliphatic groups and the charcoal to have mainly aromatic groups, through the peak analysis of solid C-13 NMR charts. 6. So, the sewer sludge is proved to have a considerable amount of aromaticity like in woody biomass containing lignin.