搜索范围
25467
关键词:'25467'
显示 1-30 共 443 条结果 关于 "25467" 范围 论文
International journal of analytical chemistry, 2012, 690356-690356 (2012-09-12)
Trimethylsilanol (TMSOH) can cause damage to surfaces of scanner lenses in the semiconductor industry, and there is a critical need to measure and control airborne TMSOH concentrations. This study develops a thermal desorption (TD)-gas chromatography (GC)-mass spectrometry (MS) method for
Analytica chimica acta, 664(1), 49-55 (2010-03-17)
A new polyethylene glycol fiber was developed for solid-phase microextraction (SPME) of styrene by electrodepositing porous Zn film on Ag wire substrate followed by coating with polyethylene glycol sol-gel (Ag/Zn/PEG sol-gel fiber). The scanning electron micrographs of fibers surface revealed
The Analyst, 127(11), 1440-1445 (2002-12-12)
A method for the determination of exhaled ethane, pentane and isoprene was developed and validated. The method was based on pre-concentration of the analytes on a multi-bed solid adsorbent tube containing Tenax TA, Carboxen 569 and Carboxen 1000, thermal desorption
Journal of environmental monitoring : JEM, 4(5), 695-705 (2002-10-29)
Ambient air spiked with 1-10 ppbv concentrations of 41 toxic volatile organic compounds (VOCs) listed in US Environmental Protection Agency (EPA) Compendium Method TO-14A was monitored using solid sorbents for sample collection and a Varian Saturn 2000 ion trap mass
Fresenius' journal of analytical chemistry, 366(4), 329-331 (2001-02-28)
The surfaces of commercially available polydimethylsiloxane (PDMS) and Carboxen-PDMS fibers for solid-phase microextraction (SPME) were investigated by optical and electron microscopy. Damage to the coating as well as contamination of new fibers and a highly variable number of pores in
Waste management (New York, N.Y.), 32(12), 2469-2481 (2012-08-14)
Municipal solid waste treatment facilities are generally faced with odorous nuisance problems. Characterizing and determining the odorous charge of indoor air through odour units (OU) is an advantageous approach to evaluate indoor air quality and discomfort. The assessment of the
Journal of occupational and environmental hygiene, 10(3), 132-142 (2013-01-30)
Passive sampling is a well-established methodology for the evaluation of exposures to environmental volatile organic compounds (VOCs). The solid-phase microextraction (SPME) technique is a reliable means of sampling VOCs in air. SPME is also being applied as a passive sampler
The Analyst, 127(8), 1045-1049 (2002-08-28)
A method was developed for the simultaneous determination of the following nine volatile sulfur compounds in gas samples: carbon disulfide, carbonyl sulfide, ethyl sulfide, ethyl methyl sulfide, hydrogen sulfide, isopropanethiol, methanethiol, methyl disulfide and methyl sulfide. The target compounds were
Analytical and bioanalytical chemistry, 394(3), 893-901 (2009-04-11)
The headspace solid-phase micro-extraction technique with on-fibre derivatisation followed by gas chromatography-tandem mass spectrometry has been evaluated for the analysis of 1,3-dichloro-2-propanol in water. An asymmetric factorial design has been performed to study the influence of five experimental factors: extraction
Journal of chromatography. A, 1064(2), 239-245 (2005-03-03)
Headspace solid-phase microextraction (HS-SPME) was studied as a solvent free alternative method for the extraction and characterisation of volatile compounds in stored potato crisps by capillary gas chromatography coupled with mass detection. Better results were obtained when extraction was carried
Journal of pharmaceutical and biomedical analysis, 84, 103-111 (2013-06-29)
In this study, a novel and efficient method based on headspace solid-phase microextraction (HS-SPME), followed by gas chromatography-mass spectrometry (GC-MS), was developed for the analysis of propolis volatile compounds. The HS-SPME procedure, whose experimental parameters were properly optimized, was carried
Journal of agricultural and food chemistry, 50(3), 449-459 (2002-01-24)
Headspace sorptive extraction (HSSE) and stir bar sorptive extraction (SBSE), two recently introduced solventless enrichment techniques, have been applied to the analysis of the headspace of Arabica roasted coffee and of the headspace of the brew and of the brew
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 1061-1062, 17-25 (2017-07-12)
Breath analysis has been gaining popularity as a non-invasive technique that is amenable to a broad range of medical uses. One of the persistent problems hampering the wide application of the breath analysis method is measurement variability of metabolite abundances
Analytical chemistry, 82(2), 707-713 (2009-12-30)
Two polymeric ionic liquids (PIL) were synthesized and employed as sorbent coatings in solid-phase microextraction (SPME) for the selective extraction of CO(2). The two coatings, poly(1-vinyl-3-hexylimidazolium) bis[(trifluoromethyl)sulfonyl]imide [poly(VHIM-NTf(2))] and poly(1-vinyl-3-hexylimidazolium) taurate [poly(VHIM-taurate)], exhibited varied selectivity toward CO(2) due to functional
Journal of chromatography. A, 1124(1-2), 11-21 (2006-04-08)
A solid-phase microextraction (SPME) method for the ultra-trace determination of brominated phenols in aqueous samples has been developed and is reported for the first time to the best of our knowledge. 3,5,3',5'-tetrabromobisphenol A (TBBPA), the most widely used brominated flame
Journal of AOAC International, 91(6), 1409-1415 (2009-02-11)
A method using solid-phase microextraction (SPME) and gas chromatography/mass spectrometry was developed and applied to the determination of volatile compounds generated in meat, at different times, from ground beef stored under refrigeration. Selection of the extractive fiber, extraction time, and
Journal of chromatography. B, Biomedical sciences and applications, 739(1), 183-190 (2000-04-01)
An analytical method for determination of isoprene in expired breath as a marker of body cholesterol synthesis was developed with a special emphasis on breath sampling. Patients were breathing controlled air using respiratory masks for 2 min (washout period) and
Forensic science international, 160(1), 44-52 (2005-09-29)
The profiling of impurities in methamphetamine (MA) using headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) is described. The extraction of the impurities with an SPME fiber was examined under varying conditions. Optimal chromatograms were obtained when a
Journal of chromatography. A, 933(1-2), 107-116 (2002-01-05)
The water uptake by the solid sorbents Carbosieve S-III, Carboxen 569, 1000 and 1001, all of which are used for sampling of volatile organic compounds from the atmosphere. was examined using a direct experimental approach. The content of retained water
Plants (Basel, Switzerland), 7(4) (2018-11-08)
Two modern rose varieties, Floribunda and Hybrid Tea, were used to analyze and identify metabolic changes after foliar application with benzyladenine (BA). Volatile organic compounds (VOCs) as metabolites were detected. Two pairs of doses of BA, at 11.16 and 17.87
Journal of chromatography. A, 1238, 15-21 (2012-04-13)
Trihalomethanes are predominantly formed during disinfection of water via reactions of the oxidant with natural organic matter. Even though chlorinated and brominated trihalomethanes are the most widespread organic contaminants in drinking water, when iodide is present in raw water iodinated
Journal of chromatography. B, Biomedical sciences and applications, 734(1), 155-162 (1999-11-26)
Methanol and its metabolite formic acid have been found extractable from human whole blood and urine by headspace solid-phase microextraction (SPME) with a Carboxen/polydimethylsiloxane fiber. The headspace SPME for formic acid was carried out after derivatization to methyl formate under
Analytical and bioanalytical chemistry, 406(1), 317-328 (2013-11-21)
Solid-phase microextraction on-fiber derivatization applied to carbonyl compounds is known, but application to indoor air is poorly developed and the methods deserve to be complemented and optimized. In this work, two derivatization reagents, pentafluorophenylhydrazine and o-2,3,4,5,6-(pentaflurobenzyl)hydroxylamine (PFBHA), and three fiber
Analytical and bioanalytical chemistry, 380(5-6), 824-830 (2004-11-02)
The aim of the study was to analyse BTEX compounds (benzene, toluene, ethylbenzene, xylenes) in air by solid phase micro-extraction/gas chromatography/mass spectrometry (SPME/GC/MS), and this article presents the features of the calibration method proposed. Examples of real-world air analysis are
Journal of chromatographic science, 39(12), 521-529 (2002-01-05)
This work presents the usefulness of five different solid-phase microextraction fibers in the screening of volatile organic compound (VOC) traces in air samples. The performances of these fibers are compared by studying the sorption kinetics in an equimolar gaseous mixture
Journal of chromatography. A, 1208(1-2), 10-15 (2008-09-06)
A new sampling method was developed for a simple and fast evaluation of volatile organic compounds (VOCs) emitted at trace levels from building materials. The device involves an emission cell coupled with solid phase microextraction (SPME) for diffusive sampling. Owing
Journal of chromatography. A, 1084(1-2), 2-6 (2005-08-24)
A headspace solid-phase microextraction (HS-SPME) procedure based on three commercialised fibers (100 microm polydimethylsiloxane, 65 microm polydimethylsiloxane-divinylbenzene and 50/30 microm divinylbenzene-Carboxen-polydimethylsiloxane) is presented for the determination of a selected essential oils in dried leaves of yacon (Smallanthus sonchifolius). The extraction
Talanta, 129, 422-430 (2014-08-17)
A commercial electronic nose (e-nose) equipped with a metal oxide sensor array was trained to recognize volatile compounds emitted by potatoes experimentally infected with Ralstonia solanacearum or Clavibacter michiganensis subsp. sepedonicus, which are bacterial agents of potato brown and ring
Journal of chromatography. A, 942(1-2), 41-52 (2002-02-02)
A solid-phase microextraction (SPME) followed by a gas chromatographic-mass spectrometric (GC-MS) determination has been developed and validated for the determination of cyprodinil and fludioxonil in white wine samples. Extraction parameters such as the selection of SPME coating, the effect of
Journal of agricultural and food chemistry, 47(2), 648-654 (1999-11-24)
A new technique using solid-phase microextraction, mass spectrometry, and multivariate analysis (SPME-MS-MVA) was developed for the study of off-flavors in milk. The analytical column of a GC/MS system was replaced with a 1-m deactivated fused-silica column, which served as a
1/15