• Korean journal of food and cookery science
• /
• v.11 no.2
• /
• pp.122-125
• /
• 1995

An attempt was made to determine the effect of the volatile components of edible wild grass by cooking. We collect the volatile components of Agrimonia Japonica by dynamic\ulcorner head space method. Samples were analyzed by gas chromatography-mass spectrometry(GC-MS). Thirty-six components, including 16 hydrocarbons, 7 alcohols, 4 esters, 7 benzoid compounds, 1 aldehyde and 1 ketone were confirmed in raw samples. Also 6 hydrocarbons identified in cooked sample. Alpha-pinene and 3-he-xane-ol were regarded as the most abundant components in raw sample. By heating of Japonica, most of the volatile compounds were disappeared, but alpha-pinene was remained abundantly.

• Journal of Sensor Science and Technology
• /
• v.23 no.5
• /
• pp.320-325
• /
• 2014

Volatile flavor compounds from milk were analyzed and identified by using the analysis methods of headspace solid phase microextraction gas chromatography/mass spectrometry (HSPME-GC/MS) and electronic nose (E-Nose) system. About 30 volatile compounds were identified by HSPME-GC/MS for the fresh and off-flavor milk samples. Also, the correlation between rancidity and ageing days of milk was obtained by the aid of principal component analysis algorithm. It shows that the E-Nose system can identify the various types of milk flavor. These results imply that the analysis method based on the E-nose system can apply to the quality control of milk flavor and the rancidity.

• Applied Chemistry for Engineering
• /
• v.30 no.6
• /
• pp.707-711
• /
• 2019

The feasibility of waste concrete as a catalyst for the effective pyrolysis of polyethylene terephthalate (PET) was examined using thermogravimetric (TG) and pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS) analyses. TG analysis results indicated that the maximum decomposition temperature of PET is not altered by the use of waste concrete, showing similar values (407 ℃ and 408 ℃ at 5 ℃/min). Meanwhile, the volatile product distribution data obtained from the Py-GC/MS analysis revealed that the use of waste concrete promoted the deoxygenation reaction via converting the oxygen containing products such as benzoic acids, benzoates, and terephthalates to valuable deoxygenated aromatic hydrocarbons including benzene, toluene, ethylbenzene, and styrene. This suggests that the waste concrete can be used as a potential catalyst for the production of valuable aromatic hydrocarbons from PET pyrolysis.

• Journal of the Korean Society of Tobacco Science
• /
• v.4 no.1
• /
• pp.61-66
• /
• 1982

Essential oil components were isolated from Korean aromatic tobaccos by using a simultaneous distillation and extraction apparatus. The essential oils were analyzed by GC/M S and date system. Forty-two volatile components were identified on the basis of their mass spectra. Determination of contents of essential oil components from Hyangcho and Sohyang was achieved by pseudo-multiple ion selection (Ml S) technique. Varietal differences were detected from the quantitative comparison of the MIS data.

• Korean Journal of Food Science and Technology
• /
• v.22 no.3
• /
• pp.261-265
• /
• 1990

The volatile components of Eucommiae foliums were extracted by simultaneous steam distillation-extraction apparatus, and analyzed by combined gas chromatography (GC) and gas chromatography-mass spectrometry(CC-MS). Thirty five components, including 7 alcohols, 3 aldehydes, 4 ketones, 2 esters. 18 hydrocarbons and 1 phenol were confirmed in Eucommiae foliums. Among total volatiles the main component it appeared to be 2-ethyl furyl acrolein, comprising about 31.4%.

• Elastomers and Composites
• /
• v.51 no.1
• /
• pp.63-67
• /
• 2016

Poly(ethylene-co-vinyl acetate) (EVA) was pyrolyzed to eliminate acetic acid of VA unit using off-line pyrolysis, and the deacetylated EVA was analyzed infrared spectroscopy (IR) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). EVA film for deacetylation was prepared by solution casting on aluminum foil and it was pyrolyzed at low temperature of $300^{\circ}C$ in the off-line pyrolysis apparatus. After deacetylation, carbon-carbon double bond (C=C) was formed by 1,2-elimination of the VA unit in the EVA backbone. Most of C=C bonds were trans-1,4-unit and 1,2-unit was also observed. Presence of the 1,2-unit in deacetylated EVA indicates that terminal or branch VA units exist in the raw EVA. Py-GC/MS chromatogram of deacetylated EVA displayed much smaller acetic acid and much more abundant other pyrolysis products than that of raw EVA, which means that the pyrolysis efficiency and separation condition were improved.

• Archives of Pharmacal Research
• /
• v.16 no.3
• /
• pp.175-179
• /
• 1993

Gas chromoatography with flame ionization detector (FID) along with mass spectrometry (GC/MS) were used for the screening and quantification of methamphetamine (MA) and its major metabolite, amphetamine (AM0, in blood and urine in eleven fatal cases in which MA abuse was suspected. Postmortem blood MA varied from $0.5-30.2\;\mu{g/ml}$, while Am levels ranged from none detected (6 of 11 cases) to 4.8 .mu.g/ml. Additionally, distribution studies were performed in three of these cases in which tissue smaples were available for evaluation. Liver contained the highest ocncentration of MA among the tissu samples. In eight of the eleven cases, when no other direct cause of death was evident (i.e. 3 cases of traumatic dath0, either no blood AM was found or the ratio of MA/AM was 3.4 or greater. These data are consistent with acute MA use followed by death due to acute drug intoxication or by the occurrence of hypersensitivity and reverse seen in cases of chronic drug abuse.

• Elastomers and Composites
• /
• v.55 no.1
• /
• pp.6-12
• /
• 2020

Poly(ethylene-co-vinyl acetate) compounds and vulcanizates containing dicumyl peroxide (DCP) (HD) were prepared, and the curing agent and reaction products were analyzed using gas chromatography/mass spectrometry (GC/MS). Samples containing trially cyanurate (TAC) and DCP (HDT) were also prepared and analyzed. Some raw DCP were decomposed in the injector region of GC to produce acetophenone. DCP was detected in the HD compound but was not observed in the HD vulcanizate, and instead acetophenone and 2-phenyl-2-propanol were detected. Both DCP and TAC were observed in the HDT compound but not in the HDT vulcanizate, where acetophenone and 2-phenyl-2-propanol were detected. Thus, some of the DCP decomposed during the compounding process. The formation mechanism for acetophenone and 2-phenyl-2-propanol during the crosslinking reaction was identified, and differences in the crosslinking reactions of HD and HDT compounds were discussed.

• YAKHAK HOEJI
• /
• v.47 no.5
• /
• pp.266-270
• /
• 2003

We evaluated four commercially available methamphetamine immunoassays for their relative cross-reactivities of amphetamine analogues in human urine: Abbott TDx, Vitalab Selectra and on-site test kits (Accusign MET, SD bioline MET). High cross-reactivities were shown at designer's drugs such as methylenedioxyamphetamine (MDA), methylenedioxymethamphetamine (MDMA) and methylenedioxyethylamphetamine (MDEA) in all of the tested immunoassays. Methoxyphenamine, fenfluramine and phentermine were positive in TDx and Selectra, but were not positive in on-site test kits. Pseudoephedrine, norpseudoephedrine, ephedrine, norephedrine, MDMA, MDA, fenfluramine and phentermine were detected by gas chromatography/mass spectrometry(GC/MS) in false positive urines. Since the overall specificity of any of the devices was not 100％, we found it is important to confirm any positive screening test result, so we developed simultaneous determination of amphetamine analogues in urines. After alkalinization of the urine samples with 6-N NaOH, the analytes were extracted using ethyl acetate, derivatized with pentafluoropropyl anhydride (PFPA) prior at GC/MS analysis.

• Analytical Science and Technology
• /
• v.17 no.6
• /
• pp.527-531
• /
• 2004

Treatment with aqueous sodium hydroxide solution plays an important role to impart certain desirable properties - feel and luster on the surface of polyester fiber. In this process alkali wastewater contains disodium terephthalate, ethylene glycol (EG) and residual sodium hydroxide. In this paper we report a new method containing the pretreatments of derivatization with benzoyl chloride and solvent extraction using pentane. The calibration curve of EG determined by GC/MS-SIM shows a good linearity in the range of 0.1 to $25{\mu}g/mL$ having the standard deviation of ${\leq}8.7%$. The recovery and the detection limit of this method are 91.9-93.7% and $0.05{\mu}g/mL$ respectively.