Search Within


Applied Filters:
Showing 1-30 of 128 results for "20273" within Papers
Alejandra Ribes et al.
Journal of chromatography. A, 1140(1-2), 44-55 (2006-12-26)
An analytical method based on thermal desorption (TD) coupled to gas chromatography (GC) and mass spectrometry detection (MS) has been developed and validated for the determination of a wide range of odor nuisance and air-quality volatile organic compounds (VOC) in
Charles F Forney et al.
Journal of food science, 83(4), 1017-1024 (2018-04-17)
Rapid methods to detect bacterial pathogens on food and strategies to control them are needed to mitigate consumer risk. This study assessed volatile emissions from whole cantaloupe melons (Cucumis melo) as an indicator of Listeria contamination and in response to
V C Gavino et al.
Analytical biochemistry, 152(2), 256-261 (1986-02-01)
The concentration of acetone dissolved in liver perfusion medium was determined by injection of the sample into a gas chromatograph equipped with a Carbopack/Carbowax-packed glass column. Interference from labile acetoacetate which readily decomposes to acetone was eliminated by treating the
C Kanz et al.
Analytical chemistry, 70(5), 913-917 (1998-03-01)
High-performance capillary electrophoresis (HPCE) with α-cyclodextrin as the chiral selector was applied to separate the enantiomers of p-sulfophenyl-2-butyrate (SP2B) and p-sulfophenyl-3-butyrate (SP3B), which occur as biodegradation intermediates of linear alkylbenzenesulfonates (LAS), the widely used anionic surfactants. With this analytical method
Eva Gallego et al.
The Science of the total environment, 618, 1440-1448 (2017-11-08)
1,3-Butadiene is a carcinogenic compound that can be emitted to the atmosphere from several sources, such as the combustion of organic matter or traffic. However, petrochemical industry is one of the main origins of this compound. Several campaigns (2013-2017) were
Ki-Hyun Kim et al.
Analytical and bioanalytical chemistry, 405(26), 8397-8408 (2013-08-03)
The combined use of sorbent tubes (ST) and thermal desorption (TD) has become the common practice for the trace-level analysis of gaseous volatile organic compounds (VOCs). In this research, the potential bias in VOC analysis due to the solvent introduced
Ikuo Ueta et al.
Journal of pharmaceutical and biomedical analysis, 88, 423-428 (2013-11-02)
A novel needle-type sample preparation device was developed for the determination of very volatile organic compounds (VVOCs) in gaseous samples by gas chromatography-mass spectrometry (GC-MS). Two types of activated-carbon-based sorbents, Carbopack X and a carbon molecular sieve (CMS), were investigated
William A McClenny et al.
Journal of environmental monitoring : JEM, 7(3), 248-256 (2005-03-01)
Diffusive sampling of a mixture of 42 volatile organic compounds (VOCs) in humidified, purified air onto the solid adsorbent Carbopack X was evaluated under controlled laboratory conditions. The evaluation included variations in sample air temperature, relative humidity and ozone concentration.
Todd McAlary et al.
Environmental science. Processes & impacts, 17(5), 896-905 (2015-04-11)
This article describes laboratory testing of four passive diffusive samplers for assessing indoor air concentrations of volatile organic compounds (VOCs), including SKC Ultra II, Radiello®, Waterloo Membrane Sampler (WMS) and Automated Thermal Desorption (ATD) tubes with two different sorbents (Tenax
Bo Strandberg et al.
Environmental science. Processes & impacts, 16(5), 1008-1014 (2014-03-04)
1,3-Butadiene and benzene are common pollutants in both workplace and ambient air and have received attention for their adverse effects on human health. In exposure studies, simple and sensitive personal monitoring methods are preferable. Thermal desorption passive samplers seem optimal
G Cosmi et al.
Clinical chemistry, 29(2), 319-321 (1983-02-01)
We describe two simple, rapid, and sensitive gas-chromatographic methods. One is for determining 3-hydroxybutyrate and lactate in plasma, the other for determining 3-hydroxybutyrate in perchloric acid extracts of blood. Samples are purified by adsorption onto graphitized carbon black (Carbopak B).
Mona Lärstad et al.
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
S A Heberle et al.
Analytical chemistry, 72(4), 840-845 (2000-03-04)
This paper describes a procedure for simultaneous enrichment, separation, and quantification of acetanilide herbicides and their major ionic oxanilic acid (OXA) and ethanesulfonic acid (ESA) metabolites in groundwater and surface water using Carbopack B as a solid-phase extraction (SPE) material.
Shaibal Mukerjee et al.
Journal of environmental monitoring : JEM, 11(1), 220-227 (2009-01-13)
This study evaluates performance of nitrogen dioxide (NO2) and volatile organic compound (VOC) passive samplers with corresponding reference monitors at two sites in the Detroit, Michigan area during the summer of 2005. Ogawa passive NO2 samplers and custom-made, re-useable Perkin-Elmer
Li-Ming Yuan et al.
Analytical chemistry, 78(18), 6384-6390 (2006-09-15)
Single-walled carbon nanotubes (SWNTs) have high surface area, high adsorption ability, and nanoscale interactions. In this study, capillary columns including SWNTs, ionic liquid (IL), and IL + SWNTs for GC were prepared. The separation results showed that SWNTs possessed a
Pasquale Avino et al.
Analytical and bioanalytical chemistry, 400(10), 3561-3571 (2011-05-10)
This paper investigates the performance of some adsorbents, Carbopack B, Tenax-GC, and XAD-2, in a SPE and GC analytical method for sampling and determining some persistent organic pollutants such as benzene, toluene, o-, m-, and p-xylenes, naphthalene, anthracene, fluorene, fluoranthene
Helena Jurdáková et al.
Journal of chromatography. A, 1194(2), 161-164 (2008-05-23)
A newly designed needle trap device with Carbopack X as a sorbent material is used for sampling, preconcentration and injection of volatile analytes benzene, toluene, ethylbenzene and xylenes (BTEX) into gas chromatograph. The closed system of stripping the analytes from
Adriana Farran et al.
Journal of chromatography. A, 1024(1-2), 267-274 (2004-02-03)
A degradation study of two phenoxy acid [(2,4-dichlorophenoxy) propanoic acid and (2,4,5-trichlorophenoxy) acetic acid] and two phenylurea (diuron and monolinuron) herbicides, spiked at 50 ppb in water, was performed. Some samples were subjected to neutral and basic hydrolysis; other samples
M Komenda et al.
Journal of chromatography. A, 995(1-2), 185-201 (2003-06-13)
In this work we present a detailed technical description of the system that was set up for long-term on-line measurements of isoprene and two of its major degradation products, methyl vinyl ketone and methacrolein in order to provide a better
Yong-Hyun Kim et al.
Journal of separation science, 38(14), 2455-2462 (2015-05-12)
In general, volatile organic compounds in ambient air are quantified by following a well-defined standard calibration procedure using a gas-/liquid-phase standard. If the liquid standard is analyzed by a thermal desorption, the solvent effect is unavoidable through the alteration of
Martina Schneider et al.
Analytical chemistry, 81(8), 3017-3021 (2009-03-26)
A variety of sorbents is available for the sampling of airborne organic pollutants. However, choosing the right sorbent for a certain analytical target is still a challenge. Here we present a systematic sorption study for a diverse set of up
J Ansbaek et al.
Microbial ecology, 5(4), 253-264 (1980-12-01)
The concentrations of volatile fatty acids were measured in the pore water of sediment from the Limfjorden, Denmark. The pore water was freeze-dried and the acids, which were redissolved in formic acid, were analyzed by gas chromatography on a Carbopack
Yong-Hyun Kim et al.
Analytical chemistry, 84(9), 4126-4139 (2012-04-04)
Sorbent tubes (STs) are highly efficient and versatile tools for collecting gaseous samples of volatile organic compounds (VOCs). In order to assess the experimental bias in their application, the relative recovery (RR) of 19 VOCs (acetaldehyde, propionaldehyde, butyraldehyde, isovaleraldehyde, valeraldehyde
Elżbieta Dobrzyńska et al.
Journal of separation science, 36(20), 3372-3378 (2013-08-21)
A needle-trap device, with immobilized sorbent inside the syringe, coupled with GC-MS was applied for air sampling and determination of chlorinated volatile organic compounds such as dichloromethane, trichloromethane, and tetrachloromethane. The application of a needle trap packed with combination of
Roy M Harrison et al.
Research report (Health Effects Institute), (143), 3-96 (2009-12-17)
The overall aim of our investigation was to quantify the magnitude and range of individual personal exposures to a variety of air toxics and to develop models for exposure prediction on the basis of time-activity diaries. The specific research goals
J H Margeson et al.
Journal of chromatographic science, 28(4), 204-209 (1990-04-01)
Chromatographic methods of analysis with FID detection are investigated for quantitation of ethylene oxide in emissions from production plants and commercial sterilizers. A column with a stationary phase of 3% Carbowax 20M on 80-100 Chromosorb 101 is used to separate
Md Ahsan Ullah et al.
Analytical and bioanalytical chemistry, 407(2), 415-426 (2014-11-20)
The superiority of thermal desorption-gas chromatography (TD-GC) applications is well known for the analysis of biogenic volatile organic compounds (BVOC). Despite the recognition of potential biases associated with sorptive loss reaction, the interaction of reactive BVOC with a sorbent tube
A Laganà et al.
Clinical chemistry, 32(3), 508-510 (1986-03-01)
In this precise, accurate, and specific liquid-chromatographic procedure for determining progesterone in serum, the serum is diluted 10-fold with water/methanol (65/35 by vol), and the progesterone is extracted from the sample by passage through a column of graphitized carbon black
Luisa Prasetyo et al.
Journal of colloid and interface science, 478, 402-412 (2016-06-28)
Adsorption isotherms and isosteric heats of krypton on a highly graphitized carbon black, Carbopack F, have been studied with a combination of Monte Carlo simulation and high-resolution experiments at 77K and 87K. Our investigation sheds light on the microscopic origin
Thomas R Rybolt et al.
Journal of colloid and interface science, 300(2), 805-808 (2006-06-17)
Five model surfaces were developed using molecular mechanics with MM2 parameters. A smooth, flat model surface was constructed of three parallel graphene layers where each graphene layer contained 127 interconnected benzene rings. Four rough surfaces were constructed by varying the
Page 1 of 5