Name: quantitative detection of trace explosive vapors by programmed temperature desorption gas chromatography-electron capture detector
Uploaded: 2014-07-25T15:00:00
Description: Watch this Scientific Journal Video about Quantitative Detection of Trace Explosive Vapors by Programmed Temperature Desorption Gas Chromatography-Electron Capture Detector at JoVE.com

Økonomisk støtte blev leveret af Department of Homeland Security Videnskab og Teknologi direktoratet.

1.. Instrument Forberedelse <ol><li> Sørg for, at instrumentet, ovn og detektor er ved RT. Sluk gasstrømning indløbet og detektoren. </li><li> Fjern TDS fra GC. Kontakt producenten brugervejledningen til instrumentet specifikke procedure. </li><li> Fjern TDS adapteren fra SNG fjorden og fjerne foringen fra SNG. </li><li> Undersøg CIS indløb for partikler og snavs, medens foringen er fjernet. Rengør synlige vragrester med trykluft, eller fortrinsvis nitrogen. </li><li> Vedhæft en ny grafit ferrul til en ny CIS l...

<ol>
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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Instrumentation+for+trace+detection+of+high+explosives.">Instrumentation for trace detection of high explosives.</a> Review of Scientific Instruments. 75 (8), 2499-2512 (2004).</li><li>Douse, J. M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Trace+analysis+of+explosives+at+the+low+picogram+level+by+silica+capillary+column+gas--liquid+chromatography+with+electron-capture+detection.">Trace analysis of explosives at the low picogram level by silica capillary column gas--liquid chromatography with electron-capture detection.</a> Journal of Chromatography A. 208 (1), 83-88 (1981).</li><li>Douse, J. M. 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E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+nitroaromatic,+nitramine,+and+nitrate+ester+explosives+in+soil+by+gas+chromatography+and+an+electron+capture+detector.">Determination of nitroaromatic, nitramine, and nitrate ester explosives in soil by gas chromatography and an electron capture detector.</a> Talanta. 54 (3), 427-438 (2001).</li><li>Field, C. R., Lubrano, A. L., Rogers, D. A., Giordano, B. C., Collins, G. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+Liquid+Deposition+Calibration+Method+for+Trace+Cyclotrimethylenetrinitramine+Using+Thermal+Desorption+Instrumentation.">Direct Liquid Deposition Calibration Method for Trace Cyclotrimethylenetrinitramine Using Thermal Desorption Instrumentation.</a> Journal of Chromatography A. 1282, 178-182 (2013).</li><li>Field, C. R., Giordano, B. C., Rogers, D. A., Lubrano, A. L., Rose-Pehrsson, S. 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Reproducerbarhed er en kritisk attribut til kvantificering af spor eksplosive dampe ved hjælp af direkte væske deposition metode med TDS-CIS-GC-ECD instrumentering og relative standardafvigelse (RSD) er ofte brugt som et parameter for reproducerbarhed. Vi har oplevet RSD for inter-og intra-prøve reproducerbarhed på cirka 5% til TNT og 10% for RDX. Enhver RSD over 15% bruges som en indikator for at kontrollere almindelige kilder til variation, der mindsker effektiviteten af ​​protokollen. Kilder til variation, de...

Gaschromatografi (GC) er et centralt instrumentel analyse teknik for Analytisk Kemi og er nok så allestedsnærværende som en varmeplade eller balance i en kemi laboratorium. GC instrumentering kan anvendes til fremstilling, identifikation og kvantificering af en lang række kemiske forbindelser og kan kobles til en række forskellige detektorer, såsom flammeionisering detektorer (FIDS), foto-ionisering detektorer (PID), termisk ledningsevne detektorer ( TCDS), capture elektron detektorer (ECDs) og massespektrometre (MS), afhængigt af analytter metode og anvendelse. Prøver kan indføres gennem en standard / uden split indløb, når man arbejder med små prøve løsninger, specialiserede headspace analyse fjorde, fastfase mikro-(SPME) sprøjter eller termisk desorption-systemer. GC-MS er ofte standard teknik, der anvendes ved validering og verificering anvendelser af alternative eller nye, påvisningsteknikker grund af dens anvendelighed, fleksibilitet,og identifikation magt med etablerede kemiske databaser og biblioteker 1 -. 7 GC og dens relaterede prøvetagning og afsløre komponenter er ideel til rutinemæssig kemisk analyse og mere specialiseret, udfordrende analytiske applikationer. En analytisk anvendelse af stigende interesse for militæret, Homeland Security, og kommercielle virksomheder er spore eksplosive dampdetektionsudstyr, med påvisning herunder identifikation og kvantificering. Trace eksplosiv dampdetektionsudstyr er en unik analytisk kemi udfordring, fordi de analytter, såsom 2,4,6-trinitrotoluen (TNT) og cyclotrimethylentrinitramin (RDX), har fysiske egenskaber, der gør dem særligt vanskelige at håndtere og separat ved hjælp af bredere, mere generisk kemisk analyse metoder. Den relativt lave damptryk og sub dele-per-million efter volumen (ppm v) mættede dampkoncentration, kombineret med relativt høje stikning koefficienter, necessitspiste særlige prøvetagningsprotokoller, instrumentering og for mængden metoder 8 -. 12 A GC koblet til et Electron Capture Detector (ECD) eller massespektrometer (MS) er en effektiv metode til kvantificering eksplosive analytter, specielt dinitrotoluen (DNT), TNT og RDX . 6,13 - 17 GC-ECD er især nyttig til nitro-energiske forbindelser på grund af deres relativt høje elektron affinitet. US Environmental Protection Agency (EPA) har skabt standardmetoder til eksplosiv analytpåvisning med GC-ECD og GC-MS, men disse metoder har fokuseret på prøver i opløsning, såsom grundvand, og ikke prøver indsamlet i dampfasen. 2 , 18-23 For at afsløre eksplosive dampe, alternative prøvetagningsprotokoller skal anvendes, såsom damp samling af adsorptionsmidlets fyldt termisk desorption prøverør, men kvantitativ påvisning fortsat vanskelig på grund af manglende damp standarder etnd kalibrering metoder, der ikke tegner sig for prøve rør og instrumentering tab. For nylig er der blevet udviklet for mængden metoder ved hjælp af termisk desorption systemer med en afkølet indsugningssystem (TDS-CIS), koblet til et GC-ECD TNT og RDX dampe. 24,25 De tab, der er forbundet med TDS-CIS-GC-ECD instrumentering for spor eksplosive dampe blev karakteriseret og tegnede sig for i eksempel kalibreringskurver hjælp af en direkte væske deposition metode på sorberende fyldt termisk desorption prøveglas. Men litteraturen fokuseret på instrumentering karakterisering og metodeudvikling, men faktisk aldrig stikprøven, analyseret eller kvantificeret eksplosive dampe, eneste løsning standarder. Heri fokuseres der på den protokol for prøvetagning og kvantificering eksplosive dampe. Protokollen og metode kan udvides til andre analytter og spore eksplosive dampe, såsom pentaerythritoltetranitrat (PETN).

<table border="0" cellpadding="0" cellspacing="0" width="638">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:127px;">Company</td>
			<td style="width:128px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:216px;">2,4,6-Trinitrotoluene (TNT)</td>
			<td style="width:127px;">Accu-Standard</td>
			<td style="width:128px;">M-8330-11-A-10X</td>
			<td>10,000 ng &#956;L-1</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Cyclotrimethylenetrinitramine (RDX)</td>
			<td style="width:127px;">Accu-Standard</td>
			<td style="width:128px;">M-8330-05-A-10X</td>
			<td>10,000 ng &#956;L-1</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:216px;">3,4-Dinitrotoluene (3,4-DNT)</td>
			<td style="width:127px;">Accu-Standard</td>
			<td style="width:128px;">S-22988-01</td>
			<td>1000 ng &#956;L-1</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Tenax&#174; TA Vapor Sample Tubes</td>
			<td style="width:127px;">Gerstel</td>
			<td style="width:128px;">009947-000-00</td>
			<td>Tenax&#174; 60/80</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">CIS4 Liner</td>
			<td style="width:127px;">Gerstel</td>
			<td style="width:128px;">014652-005-00</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Transfer Line Ferrule</td>
			<td style="width:127px;">Gerstel</td>
			<td style="width:128px;">001805-008-00</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Inlet Liner Ferrule</td>
			<td style="width:127px;">Gerstel</td>
			<td style="width:128px;">001805-040-00</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">CIS4 Ferrule</td>
			<td style="width:127px;">Gerstel</td>
			<td style="width:128px;">007541-010-00</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">ECD Detector Ferrule</td>
			<td style="width:127px;">Aglient</td>
			<td style="width:128px;">5181-3323</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">DB5-MS Column</td>
			<td style="width:127px;">Res-Tek</td>
			<td style="width:128px;">12620</td>
			<td></td>
		</tr>
	</tbody>
</table>

quantitative detection of trace explosive vapors by programmed temperature desorption gas chromatography-electron capture detector

Den direkte flydende aflejring af opløsning standarder på sorberende fyldt termisk desorption rør anvendes til kvantitativ analyse af spor eksplosive damp prøver. Den direkte væske deposition metode giver et højere troskab mellem analysen af damp prøver og analysen af løsningen standarder end at bruge separate injektionssteder metoder for dampe og løsninger, dvs prøver indsamlet på damp indsamling rør og standarder udarbejdet i opløsning hætteglas. Derudover kan metoden redegøre for instrumentering tab, hvilket gør den ideel til at minimere variabilitet og kvantitativ spor kemisk sporingsudstyr. Gaskromatografi med en elektron capture detektor er en instrumentering konfiguration følsom over nitro-energetik, såsom TNT og RDX, på grund af deres relativt høje elektron affinitet. Imidlertid er vanskeligt uden levedygtige damp standarder damp kvantificering af disse forbindelser. Således vi fjerne kravet om damp standarder ved at kombinerefølsomheden af ​​instrumentering med en direkte væske deposition protokol til at analysere spor eksplosive damp prøver.

Indhentning kvantitative resultater for spor eksplosive damp prøver begynder med oprettelse af en kalibreringskurve for TDS-CIS-GC-ECD instrumentering ved hjælp af den direkte væske deposition metode til løsning standarder på prøveglas til at redegøre for tab instrument og forskelle mellem løsning standarder og damp prøver. TDS-CIS-GC-ECD instrumentering og en fremgangsmåde til TNT og RDX sporanalyse er tidligere blevet beskrevet i detaljer andetsteds, men målerparametre er opsummeret i tabel 1.</stro...

Watch this Scientific Journal Video about Quantitative Detection of Trace Explosive Vapors by Programmed Temperature Desorption Gas Chromatography-Electron Capture Detector at JoVE.com

Quantitative Detection of Trace Explosive Vapors by Programmed Temperature Desorption Gas Chromatography-Electron Capture Detector

Trace eksplosive dampe af TNT og RDX opsamlet på sorberende fyldt termisk desorption rør blev analyseret ved hjælp af en programmeret temperatur desorptionssystem koblet til GC med en elektron capture detektor. Den instrumentel analyse kombineres med direkte væske deposition metode til at reducere prøve variabilitet og redegøre for instrumentering afdrift og tab.

Kvantitativ påvisning af spor af eksplosive dampe ved indstillede temperatur Desorption gaskromatografi-Electron Capture Detector

The direct liquid deposition of solution standards onto sorbent-filled thermal desorption tubes is used for the quantitative analysis of trace explosive ...

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Facile Preparation of 4-Substituted Quinazoline Derivatives

Facile Fremstilling af 4-substituerede quinazolinderivater

Reported in this paper is a very simple method for direct preparation of 4-substituted quinazoline derivatives from a reaction between substituted ...

Temperature-programmed Deoxygenation of Acetic Acid on Molybdenum Carbide Catalysts

Temperatur-programmeret iltsvind i eddikesyre på Molybdæn Carbide Katalysatorer

Temperature programmed reaction (TPRxn) is a simple yet powerful tool for screening solid catalyst performance at a variety of conditions. A TPRxn system ...

Combustion Chemistry of Fuels: Quantitative Speciation Data Obtained from an Atmospheric High-temperature Flow Reactor with Coupled Molecular-beam Mass Spectrometer

Forbrænding kemien for brændsler: kvantitative artsdannelse Data indhentet fra en atmosfærisk høj temperatur Flow reaktor med kombineret Molekylær-beam massespektrometer

This manuscript describes a high-temperature flow reactor experiment coupled to the powerful molecular beam mass spectrometry (MBMS) technique. This ...

Reducing Willow Wood Fuel Emission by Low Temperature Microwave Assisted Hydrothermal Carbonization

Reduktion af Willow Wood brændstof emission ved lav temperatur mikrobølge assisteret hydrotermisk Carbonization

Biomass is a sustainable fuel, as its CO2 emissions are reintegrated in biomass growth. However, the inorganic precursors in the biomass cause a negative ...

A Two-Step Pyrolysis-Gas Chromatography Method with Mass Spectrometric Detection for Identification of Tattoo Ink Ingredients and Counterfeit Products

En to-trins pyrolyse-gaskromatografi metode med massespektrometrisk detektion til identifikation af tatovering blæk ingredienser og forfalskede produkter

Tattoo inks are complex mixtures of ingredients. Each of them possesses different chemical properties which have to be addressed upon chemical analysis. ...

Analysis of Complex Molecules and Their Reactions on Surfaces by Means of Cluster-Induced Desorption/Ionization Mass Spectrometry

Analyse af komplekse molekyler og deres reaktioner på overflader ved hjælp af cluster-induceret desorption/ionisering massespektrometri

Desorption/Ionization Induced by Neutral SO2 Clusters (DINeC) is employed as a very soft and efficient desorption/ionization technique for mass ...

Nitrogen Compound Characterization in Fuels by Multidimensional Gas Chromatography

Nitrogen forbindelse karakterisering i brændstoffer ved flerdimensional gaskromatografi

Certain nitrogen-containing compounds can contribute to fuel instability during storage. Hence, detection and characterization of these compounds is ...