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You searched for: Subject gas chromatography-mass spectrometry Remove constraint Subject: gas chromatography-mass spectrometry Subject ionization Remove constraint Subject: ionization Subject air Remove constraint Subject: air Text Availability Citation in PubAg Remove constraint Text Availability: Citation in PubAg
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1. Analysis of steroids in urine by gas chromatography-capillary photoionization-tandem mass spectrometry

Author:
Pöhö, Päivi; Scholz, Karen; Kärkkäinen, Niina; Haapala, Markus; Räikkönen, Heikki; Kostiainen, Risto; Vaikkinen, Anu
Source:
Journal of chromatography 2019 v.1598 pp. 175-182
ISSN:
0021-9673
Subject:
air; cations; detection limit; fluorides; gas chromatography-mass spectrometry; humans; hydrolysis; ionization; nitrogen; oxidation; quantitative analysis; spectrometers; standard deviation; steroids; tandem mass spectrometry; urine
Abstract:
... A new heated capillary photoionization (CPI) ion source design was developed to photoionize analytes inside a transfer capillary between a gas chromatograph (GC) and a mass spectrometer (MS). The CPI setup included a wide, oval-shaped vacuum-ultraviolet (VUV) transparent magnesium fluoride (MgF₂) window to maximize photoionization efficiency and thus sensitivity. The source contained a nitrogen ho ...
DOI:
10.1016/j.chroma.2019.03.061

2. Detailed Speciation of Intermediate Volatility and Semivolatile Organic Compound Emissions from Gasoline Vehicles: Effects of Cold-Starts and Implications for Secondary Organic Aerosol Formation

Author:
Drozd, Greg T.; Zhao, Yunliang; Saliba, Georges; Frodin, Bruce; Maddox, Christine; Oliver Chang, M.-C.; Maldonado, Hector; Sardar, Satya; Weber, Robert Jay; Robinson, Allen L.; Goldstein, Allen H.
Source:
Environmental science & technology 2018 v.53 no.3 pp. 1706-1714
ISSN:
1520-5851
Subject:
BTEX (benzene, toluene, ethylbenzene, xylene); aerosols; air; air pollution; benzene; certification; desorption; ethylbenzene; filters; gas chromatography-mass spectrometry; gasoline; ionization; oils; oxidation; particulate emissions; pollution control; quartz; toluene; volatile organic compounds; xylene; California
Abstract:
... Over the past two decades vehicle emission standards in the United States have been dramatically tightened with the goal of reducing urban air pollution. Secondary organic aerosol (SOA) is the dominant contributor to urban organic aerosol. Experiments were conducted at the California Air Resources Board Haagen-Smit Laboratory to characterize exhaust organics from 20 gasoline vehicles recruited fro ...
DOI:
10.1021/acs.est.8b05600

3. Depth treatment of coal-chemical engineering wastewater by a cost-effective sequential heterogeneous Fenton and biodegradation process

Author:
Fang, Yili; Yin, Weizhao; Jiang, Yanbin; Ge, Hengjun; Li, Ping; Wu, Jinhua
Source:
Environmental science and pollution research international 2018 v.25 no.13 pp. 13118-13126
ISSN:
0944-1344
Subject:
air; biodegradation; biological treatment; butyric acid; chemical oxygen demand; color; cost effectiveness; decolorization; engineering; gas chromatography-mass spectrometry; hydrogen peroxide; ionization; iron; operating costs; pH; sludge; spectrometers; wastewater
Abstract:
... In this study, a sequential Fe⁰/H₂O₂ reaction and biological process was employed as a low-cost depth treatment method to remove recalcitrant compounds from coal-chemical engineering wastewater after regular biological treatment. First of all, a chemical oxygen demand (COD) and color removal efficiency of 66 and 63% was achieved at initial pH of 6.8, 25 mmol L⁻¹ of H₂O₂, and 2 g L⁻¹ of Fe⁰ in the ...
DOI:
10.1007/s11356-018-1571-8

4. Novel collection method for volatile organic compounds (VOCs) from dogs B Analytical technologies in the biomedical and life sciences

Author:
Holderman, Chris J.; Kaufman, Phillip E.; Booth, Matthew M.; Bernier, Ulrich R.
Source:
Journal of chromatography 2017 v.1061-1062 pp. 1-4
ISSN:
1570-0232
Subject:
Culicidae; air; alcohols; aldehydes; aromatic compounds; arthropods; carbon dioxide; carboxylic acids; disease diagnosis; dog breeds; dogs; fur; gas chromatography-mass spectrometry; heartworms; heat; hosts; ionization; stainless steel; volatile organic compounds; water vapor
Abstract:
... Host derived chemical cues are an important aspect of arthropod attraction to potential hosts. Host cues that act over longer distances include CO2, heat, and water vapor, while cues such as volatile organic compounds (VOCs) act over closer distances. Domestic dogs are important hosts for disease cycles that include dog heartworm disease vectored by mosquitoes, however the host VOCs utilized by ve ...
DOI:
10.1016/j.jchromb.2017.06.044

5. Open Probe fast GC–MS — combining ambient sampling ultra‐fast separation and in‐vacuum ionization for real‐time analysis

Author:
Keshet, U.; Alon, T.; Fialkov, A. B.; Amirav, A.
Source:
Journal of mass spectrometry 2017 v.52 no.7 pp. 417-426
ISSN:
1076-5174
Subject:
Cannabis; air; blood; canola oil; cholesterol; computer software; detection limit; estradiol; flame retardants; flowers; free fatty acids; gas chromatography-mass spectrometry; glass; heroin; humans; ibuprofen; ionization; olive oil; ovens; plastics; reserpine; spectrometers; tetrahydrocannabinol; trinitrotoluene; vitamin E; volatilization
Abstract:
... An Open Probe inlet was combined with a low thermal mass ultra‐fast gas chromatograph (GC), in‐vacuum electron ionization ion source and a mass spectrometer (MS) of GC–MS for obtaining real‐time analysis with separation. The Open Probe enables ambient sampling via sample vaporization in an oven that is open to room air, and the ultra‐fast GC provides ~30‐s separation, while if no separation is req ...
DOI:
10.1002/jms.3941

6. Discrimination of bacteria by rapid sensing their metabolic volatiles using an aspiration-type ion mobility spectrometer (a-IMS) and gas chromatography-mass spectrometry GC-MS

Author:
Ratiu, Ileana Andreea; Bocos-Bintintan, Victor; Patrut, Adrian; Moll, Victor Hugo; Turner, Matthew; Thomas, C.L. Paul
Source:
Analytica chimica acta 2017
ISSN:
0003-2670
Subject:
Staphylococcus aureus; ionization; qualitative analysis; headspace analysis; bacteria; data collection; air; information processing; Escherichia coli; gas chromatography-mass spectrometry; electric field; microbial culture; monitoring; models; principal component analysis; detectors; electrical equipment; culture media; adsorption; ions; spectrometers; Bacillus subtilis; desorption
Abstract:
... The objective of our study was to investigate whether one may quickly and reliably discriminate different microorganism strains by direct monitoring of the headspace atmosphere above their cultures. Headspace samples above a series of in vitro bacterial cultures were directly interrogated using an aspiration type ion mobility spectrometer (a-IMS), which produced distinct profiles (“fingerprints”) ...
DOI:
10.1016/j.aca.2017.06.031

7. Optimisation of pre-treatment and ionisation for GC/MS analysis for the determination of chlorinated PAHs in atmospheric particulate samples

Author:
Kamiya, Yuta; Ikemori, Fumikazu; Ohura, Takeshi
Source:
International journal of environmental analytical chemistry 2015 v.95 no.12 pp. 1157-1168
ISSN:
1029-0397
Subject:
air; fractionation; gas chromatography-mass spectrometry; hexane; ionization; methylene chloride; particulates; pollutants; polycyclic aromatic hydrocarbons; pretreatment; sampling; silica gel; surveys
Abstract:
... Chlorinated polycyclic aromatic hydrocarbons (ClPAHs) have been discovered to represent ubiquitous environmental pollutants in the last decade. In the present study, sample pre-treatment and ionisation conditions associated with the gas chromatography/mass spectrometry (GC/MS) analysis of ClPAHs were evaluated. The optimal pre-treatment of ambient air particulate samples was achieved using fractio ...
DOI:
10.1080/03067319.2015.1048439

8. Combined Impact of Branching and Unsaturation on the Autoignition of Binary Blends in a Motored Engine

Author:
Kang, Dongil; Kirby, Stephen; Agudelo, John; Lapuerta, Magín; Al-Qurashi, Khalid; Boehman, André L.
Source:
Energy & Fuels 2014 v.28 no.11 pp. 7203-7215
ISSN:
1520-5029
Subject:
air; fuels; gas chromatography-mass spectrometry; heat; ionization; iso-octanes; oxidation; temperature
Abstract:
... The impact of a branched and unsaturated compound (diisobutylene) mixed with simple hydrocarbons such as n-heptane and isooctane in binary blends on the autoignition behavior were investigated in a modified cooperative fuel research (CFR) engine at an equivlanece ratio of 0.5 and intake temperature of 120 °C. From this test condition, a homogeneous charge of fuel and intake air can be achieved. Th ...
DOI:
10.1021/ef501629p

9. Development and validation of a cryogen-free automatic gas chromatograph system (GC-MS/FID) for online measurements of volatile organic compounds

Author:
Wang, Ming; Zeng, Limin; Lu, Sihua; Shao, Min; Liu, Xinglong; Yu, Xuena; Chen, Wentai; Yuan, Bin; Zhang, Qian; Hu, Min; Zhang, Zhanyi
Source:
Analytical methods 2014 v.6 no.23 pp. 9424-9434
ISSN:
1759-9679
Subject:
acetone; acetylene; air; alkanes; alkenes; aromatic compounds; cooling; flame ionization; gas chromatography-mass spectrometry; ionization; mixing ratio; spectrometers; temperature; volatile organic compounds
Abstract:
... An automatic gas chromatograph system equipped with a mass spectrometer and a flame ionization detector (GC-MS/FID) was developed for online measurements of volatile organic compounds (VOCs) in the atmosphere. This system consisted of a custom-built cryogen-free cooling device that can create an ultra-low temperature of −165 °C, a two-channel sampling and pre-concentration system, and a commercial ...
DOI:
10.1039/c4ay01855a

10. Sensitive Method for Quantification of Octamethylcyclotetrasiloxane (D4) and Decamethylcyclopentasiloxane (D5) in End-Exhaled Air by Thermal Desorption Gas Chromatography Mass Spectrometry

Author:
Biesterbos, Jacqueline W. H.; Beckmann, Gwendolyn; Anzion, Rob B. M.; Ragas, Ad M. J.; Russel, Frans G. M.; Scheepers, Paul T. J.
Source:
Analytical chemistry 2014 v.86 no.12 pp. 5794-5799
ISSN:
1520-6882
Subject:
absorbed dose; air; desorption; exposure assessment; gas chromatography-mass spectrometry; ingredients; ionization; ions; isotope labeling; personal care products; samplers; siloxanes; stable isotopes
Abstract:
... Octamethylcyclotetrasiloxane (D4) and decamethylpentasiloxane (D5) are used as ingredients for personal care products (PCPs). Because of the use of these PCPs, consumers are exposed daily to D4 and D5. A sensitive analytical method was developed for analysis of D4 and D5 in end-exhaled air by thermal desorption gas chromatography mass spectrometry (TD-GC-MS), to determine the internal dose for con ...
DOI:
10.1021/ac5004695

11. Fe3O4 Nanoparticles and Carboxymethyl Cellulose: A Green Option for the Removal of Atmospheric Benzene, Toluene, Ethylbenzene, and o-Xylene (BTEX)

Author:
Eltouny, Nermin A.; Ariya, Parisa A.
Source:
Industrial & Engineering Chemistry Research 2012 v.51 no.39 pp. 12787-12795
ISSN:
1520-5045
Subject:
BTEX (benzene, toluene, ethylbenzene, xylene); X-ray diffraction; X-ray photoelectron spectroscopy; adsorbents; adsorption; aerosols; air; benzene; carboxymethylcellulose; cations; engineering; ethylbenzene; gas chromatography-mass spectrometry; ionization; iron oxides; models; nanoparticles; remediation; toluene; transmission electron microscopy; xylene
Abstract:
... In this work, we investigate the interaction of gaseous benzene, toluene, ethylbenzene, and o-xylene (BTEX) with Fe₃O₄ nanoparticles and demonstrate the potential application of Fe₃O₄ nanoparticles as adsorbents for BTEX. On the basis of X-ray diffraction, transmission electron microscopy, gas chromatography–mass spectrometry, and gas chromatography–flame ionization detection results, using toluen ...
DOI:
10.1021/ie3019092

12. Determination of polycyclic aromatic hydrocarbons and their oxy-, nitro-, and hydroxy-oxidation products

Author:
Cochran, R.E.; Dongari, N.; Jeong, H.; Beránek, J.; Haddadi, S.; Shipp, J.; Kubátová, A.
Source:
Analytica chimica acta 2012 v.740 pp. 93-103
ISSN:
0003-2670
Subject:
air; derivatization; gas chromatography-mass spectrometry; ionization; methane; monitoring; oxidation; particulates; polycyclic aromatic hydrocarbons; smoke; solid phase extraction; temperature
Abstract:
... A sensitive method has been developed for the trace analysis of PAHs and their oxidation products (i.e., nitro-, oxy-, and hydroxy-PAHs) in air particulate matter (PM). Following PM extraction, PAHs, nitro-, oxy-, and hydroxy-PAHs were fractionated using solid phase extraction (SPE) based on their polarities. Gas chromatography–mass spectrometry (GC–MS) conditions were optimized, addressing inject ...
DOI:
10.1016/j.aca.2012.05.050

13. Products of the OH radical-initiated reactions of 2- and 3-hexyl nitrate

Author:
Aschmann, Sara M.; Arey, Janet; Atkinson, Roger
Source:
Atmospheric environment 2012 v.46 pp. 264-270
ISSN:
1352-2310
Subject:
air; atmospheric chemistry; atmospheric pressure; flame ionization; free radicals; gas chromatography-mass spectrometry; ionization; isomerization; molecular weight; nitrates; tandem mass spectrometry
Abstract:
... Products of the gas-phase reaction of OH radicals with 2-hexyl nitrate (containing 13% 3-hexyl nitrate) have been investigated by gas chromatography with mass spectral and flame ionization detection, and by direct air sampling atmospheric pressure ionization tandem mass spectrometry. The products identified and quantified from 2-hexyl nitrate were: 2-hexanone (8.6 ± 1.3%), propanal (3.4 ± 0.8%), b ...
DOI:
10.1016/j.atmosenv.2011.09.073