The authors would like to acknowledge support from the Government of Canada's interdepartmental Program of Energy Research and Development, PERD 113, Petroleum Conversion for Cleaner Air. N.E.H would like to acknowledge her Natural Sciences and Engineering Research Council of Canada Visiting Fellowship.

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</ol>

The authors have nothing to disclose.

Al fine di ottenere una misura ottimale di H 2 S, questo metodo impiega un interruttore decani, risciacquo e un rivelatore a chemiluminescenza di zolfo (SCD). Una colonna dimetilpolisilossano viene utilizzato come prima colonna GC dimensioni, e serve a ritardare il movimento di idrocarburi pesanti presenti nel campione in modo che non contaminare colonna PLOT. Questo effetto è arricchito da un luogo fresco (50 ° C) separazione iniziale. Gas leggeri passano attraverso la prima colonna e dimensione vengono ca...

Un&#39;analisi accurata del petrolio greggio è essenziale per l&#39;industria petrolifera e del gas, i regolamenti ed economia di salute e sicurezza sono funzioni della qualità dell&#39;olio. Per proteggere i trasportatori di campioni grezzi, è necessario determinare le proprietà di campioni grezzi di sviluppare norme di sicurezza da applicare in caso di emissione o fuoriuscita. In particolare, la quantificazione del solfuro di idrogeno (H 2 S) è importante, per la sua elevata tossicità in fase gassosa; esposizioni a partire da 100 ppm possono essere fatali (http://www.cdc.gov/niosh/idlh/7783064.html) 1,2. Disciolto H 2 S in campioni grezzi è generalmente considerato corrosivo 3,4, e può disattivare catalizzatori usati per trattare l&#39;olio 5-7. La rimozione di H 2 S da flussi di petrolio greggio è ideale, ma senza un metodo per misurare disciolto H 2 S, è difficile valutare il successo di trattamenti di rimozione. Per queste ragioni, questo protocollo è stato sviluppato per misurare dissolved H 2 S in campioni di olio greggio pesanti come sabbie bituminose canadesi greggi. Un certo numero di metodi standard esiste per la quantificazione di H 2 S in campioni di petrolio o combustibile basato leggeri, ma nessuno è stato convalidato per l&#39;uso con i greggi pesanti comunemente estratti dalle sabbie bituminose canadesi. H 2 S e mercaptani sono determinati utilizzando una tecnica di titolazione dalla Universal Oil Products (UOP) metodo 163 8, ma questo metodo soffre di facile interpretazione pregiudizio che deriva dalla lettura manuale di curve di titolazione. Institute of Petroleum metodo (IP) 570 utilizza una H 2 S analizzatore di specialità che riscalda campioni di olio combustibile 9, e beneficia di semplicità e la portabilità, ma manca la precisione con i campioni più pesanti di 10. L&#39;American Society for Testing and Materials (ASTM) Metodo D5623 utilizza gascromatografia (GC) con raffreddamento criogenico e zolfo determinazione selettiva per misurare H 2 S in liquidi petrolchimici11,12. Questo standard potrebbe essere migliorata per utilizzare una separazione ambiente e anche essere applicata a greggi più pesanti, quindi è stato utilizzato come base per il protocollo qui discusso. GC è una tecnica molto utilizzato per l&#39;analisi di campioni di petrolio. I campioni vengono vaporizzati in ingresso calda e separazioni si verificano in fase gassosa. La separazione di fase gas GC rende ideale per l&#39;analisi di H 2 S, in quanto è facilmente liberato dal campione liquido durante il riscaldamento in ingresso. Metodi GC possono essere creati e personalizzati per i vari campioni, a seconda dei programmi temperatura utilizzate, colonne attuati, e l&#39;uso di cromatografia multidimensionale 13-15. Ci sono stati una serie di recenti sviluppi per la misurazione di H 2 S utilizzando GC. Luong et al. Dimostrato H 2 S ed altri composti di zolfo misurazione della luce in distillati leggeri e medi usando GC multidimensionale e Deans switching, ma il metodo non haancora applicata a greggi pesanti 16. Di Sanzo et al. H anche quantificato 2 S a benzina utilizzando GC, tuttavia anche non è stato utilizzato su greggi più pesanti, e richiede di raffreddamento 17 sub-ambient. Il metodo qui presentato dimostra notevole risparmio di tempo nel corso di questi metodi precedenti, con un tempo di analisi completato 5 min, rispetto a 10 min (Luong) e 40 min (Di Sanzo). Purtroppo, l&#39;attuazione di questi metodi nel nostro laboratorio per confrontare la precisione non è stato possibile a causa di attrezzature e di tempo restrizioni. GC multidimensionale permette di sfruttare la selettività delle due colonne, piuttosto che una singola colonna. In GC convenzionale, separazione avviene in una colonna. In caso di GC multidimensionale, il campione viene separato in due colonne diverse, migliorando la separazione e la selettività. L&#39;interruttore Deans è un dispositivo utilizzato per assumere una configurazione di colonna bidimensionale. Lo switch utilizza una valvola esterna a direflusso di gas ct da un ingresso sull&#39;interruttore a una delle due porte di uscita 18-20. Effluente dalla prima colonna può essere indirizzato in entrambe le direzioni; in questo caso, zolfo gas leggeri &quot;cut cuore&quot; 21 dalla prima separazione di uno strato poroso tubolare aperto (PLOT) colonna per la separazione secondaria, che ha dimostrato di essere eccellente per la separazione di H 2 S da altri gas di zolfo luce (http://www.chem.agilent.com/cag/cabu/pdf/gaspro.pdf) 22-24. Un rivelatore chemiluminescenza zolfo viene utilizzato per la rivelazione, fornendo selettività per composti solforati ed eliminare possibili interferenze da altri gas leggeri che possono essere stati trasferiti alla colonna PLOT durante il taglio cuore. Idrocarburi dal campione greggio vengono trattenuti sulla prima colonna e dimensione vengono rimossi durante un procedimento di controlavaggio; questo protegge colonna PLOT da ogni contaminazione 25-27. Questo approccio è stato anche implementato con successo per l&#39;analeYsis di inibitori di ossidazione in oli per trasformatori 28. Qui, un metodo GC bidimensionale è impiegata per l&#39;analisi e la quantificazione di H 2 S disciolto in campioni di olio greggio pesante. Il metodo è dimostrato di essere applicabile in un ampio intervallo di concentrazioni H 2 S, e può anche essere usato per misurare H 2 S in campioni di fase gas.

<table><tbody><tr><td>Deans switch</td><td>Agilent</td><td>G2855A</td><td>Or equivalent flow switching device</td></tr><tr><td>Restrictor tubing&amp;nbsp;</td><td>Agilent</td><td>160-2615-10</td><td>Fused silica, deactivated, 180 &amp;micro;m</td></tr><tr><td>HP-PONA column</td><td>Agilent</td><td>19091S-001</td><td></td></tr><tr><td>GasPro column</td><td>Agilent</td><td>113-4332</td><td></td></tr><tr><td>Sulfur chemiluminescence detector, 355</td><td>Agilent/Sievers</td><td>G6603A</td><td></td></tr><tr><td>H&lt;sub&gt;2&lt;/sub&gt;S calibration standard, in He</td><td>Air Liquide</td><td>Custom order</td><td>211 ppm H&lt;sub&gt;2&lt;/sub&gt;S</td></tr><tr><td>CS&lt;sub&gt;2&lt;/sub&gt;</td><td>Fisher Scientific</td><td>C184-500</td><td></td></tr><tr><td>Toluene, HPLC grade</td><td>Fisher Scientific</td><td>T290-4</td><td></td></tr><tr><td>Gas bag, 2 L</td><td>Calibrated Instruments, Inc.</td><td>GSB-P/2</td><td>Twist on/off nozzle</td></tr><tr><td>250 &amp;micro;l gas tight syringe</td><td>Hamilton</td><td>81130</td><td></td></tr><tr><td>500 ml amber glass bottle</td><td>Scientific Specialties</td><td>N73616</td><td></td></tr><tr><td>Open top screw caps</td><td>Scientific Specialties</td><td>169628</td><td></td></tr><tr><td>Tegrabond disc for screw caps</td><td>Chromatographic Specialties</td><td>C889125C</td><td>25 mm, 10/90 MIL</td></tr><tr><td>1 ml gas tight syringe</td><td>Hamilton</td><td>81330</td><td></td></tr><tr><td>2.5% H&lt;sub&gt;2&lt;/sub&gt;S in He gas standard</td><td>Air Liquide</td><td>Custom order</td><td></td></tr></tbody></table>

measurement of h2s in crude oil and crude oil headspace using multidimensional gas chromatography, deans switching and sulfur-selective detection

Un metodo per l&#39;analisi di solfuro di idrogeno disciolto in campioni di greggio è dimostrata mediante gascromatografia. Al fine di eliminare efficacemente interferenze, è prevista una configurazione a due colonne dimensionale, con un interruttore Deans impiegato per trasferire idrogeno solforato dalla prima alla seconda colonna (cuore-taglio). Campioni liquidi grezzi vengono prima separati su una colonna dimetilpolisilossano, e gas leggeri sono cuore-tagliare e ulteriormente separati su una colonna strato poroso legato tubolare aperto (PLOT) che è in grado di separare il solfuro di idrogeno da altre specie di zolfo leggeri. L&#39;idrogeno solforato viene rilevato con un rivelatore chemiluminescenza di zolfo, aggiungendo un ulteriore livello di selettività. Dopo separazione e rilevamento di solfuro di idrogeno, il sistema è backflush per rimuovere gli idrocarburi altobollenti presenti nei campioni grezzi e per preservare l&#39;integrità cromatografica. Disciolto solfuro di idrogeno è stato quantificato in campioni liquidi da 1.1 al 500 ppm, dimostrando ampia applicabilità a una serie di campioni. Il metodo è stato anche applicato con successo per l&#39;analisi di campioni di gas dai sacchi greggio spazio di testa Idrocarburi processo, con misura da 0,7 a 9.700 ppm di idrogeno solforato.

Per ottenere una quantificazione affidabile di H 2 S per campioni sia liquidi e gas, è necessaria una calibrazione corretta. Per le iniezioni di taratura e iniezioni di esempio, il picco H 2 S non dovrebbe essere sovrappone picchi vicini e dovrebbe avere un area di picco riproducibile. Figura 3 mostra una iniezione di un campione di gas in cui il gas è troppo concentrato per questo metodo. Si è constatato che le concentrazioni di gas superiori a 500 ppm utilizzando una siringa d...

Watch this Scientific Journal Video about Measurement of H2S in Crude Oil and Crude Oil Headspace Using Multidimensional Gas Chromatography, Deans Switching and Sulfur-selective Detection at JoVE.com

Measurement of H2S in Crude Oil and Crude Oil Headspace Using Multidimensional Gas Chromatography, Deans Switching and Sulfur-selective Detection

A multidimensional gas chromatography method for the analysis of dissolved hydrogen sulfide in liquid crude oil samples is presented. A Deans switch is used to heart-cut light sulfur gases for separation on a secondary column and detection on a sulfur chemiluminescence detector.

Misurazione di H<sub&gt; 2</sub&gt; S in Crude Oil e petrolio greggio Headspace Utilizzando multidimensionale gascromatografia, Presidi di commutazione e di rilevazione zolfo selettivo

A method for the analysis of dissolved hydrogen sulfide in crude oil samples is demonstrated using gas chromatography. In order to effectively eliminate ...

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Measurement of H2S in Crude Oil and Crude Oil Headspace Using Multidimensional Gas Chromatography, Deans Switching and Sulfur-selective Detection

19.1K Views.  Natural Resources Canada. A multidimensional gas chromatography method for the analysis of dissolved hydrogen sulfide in liquid crude oil samples is presented. A Deans switch is used to heart-cut light sulfur gases for separation on a secondary column and detection on a sulfur chemiluminescence detector. 

Video: Measurement of H2S in Crude Oil and Crude Oil Headspace Using Multidimensional Gas Chromatography, Deans Switching and Sulfur-selective Detection

Quantitative Detection of Trace Explosive Vapors by Programmed Temperature Desorption Gas Chromatography-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 vapor samples. The direct liquid deposition method yields a higher fidelity between the analysis of vapor samples and the analysis of solution standards than using separate injection methods for vapors and solutions, i.e., samples collected on vapor collection tubes and standards prepared in solution vials. Additionally, the method can account for instrumentation losses, which makes it ideal for minimizing variability and quantitative trace chemical detection. Gas chromatography with an electron capture detector is an instrumentation configuration sensitive to nitro-energetics, such as TNT and RDX, due to their relatively high electron affinity. However, vapor quantitation of these compounds is difficult without viable vapor standards. Thus, we eliminate the requirement for vapor standards by combining the sensitivity of the instrumentation with a direct liquid deposition protocol to analyze trace explosive vapor samples.

Trace explosive vapors of TNT and RDX collected on sorbent-filled thermal desorption tubes were analyzed using a programmed temperature desorption system coupled to GC with an electron capture detector. The instrumental analysis is combined with direct liquid deposition method to reduce sample variability and account for instrumentation drift and losses.

Quantitativa Rilevamento di Trace vapori esplosivi di temperatura programmata Desorption Gas Detector cattura cromatografia-Electron

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

Ricerca

Chimica

Light-driven Enzymatic Decarboxylation

Oxidoreductases belong to the most-applied industrial enzymes. Nevertheless, they need external electrons whose supply is often costly and challenging. Recycling of the electron donors NADH or NADPH requires the use of additional enzymes and sacrificial substrates. Interestingly, several oxidoreductases accept hydrogen peroxide as electron donor. While being inexpensive, this reagent often reduces the stability of enzymes. A solution to this problem is the in situ generation of the cofactor. The continuous supply of the cofactor at low concentration drives the reaction without impairing enzyme stability. This paper demonstrates a method for the light-catalyzed in situ generation of hydrogen peroxide with the example of the heme-dependent fatty acid decarboxylase OleTJE. The fatty acid decarboxylase OleTJE was discovered due to its unique ability to produce long-chain 1-alkenes from fatty acids, a hitherto unknown enzymatic reaction. 1-alkenes are widely used additives for plasticizers and lubricants. OleTJE has been shown to accept electrons from hydrogen peroxide for the oxidative decarboxylation. While addition of hydrogen peroxide damages the enzyme and results in low yields, in situ generation of the cofactor circumvents this problem. The photobiocatalytic system shows clear advantages regarding enzyme activity and yield, resulting in a simple and efficient system for fatty acid decarboxylation.

We describe a protocol for the light-catalyzed generation of hydrogen peroxide &#8212; a cofactor for oxidative transformations.

Enzimatica decarbossilazione Luce-driven

Oxidoreductases belong to the most-applied industrial enzymes. Nevertheless, they need external electrons whose supply is often costly and challenging. ...

Chemical Analysis of Water-accommodated Fractions of Crude Oil Spills Using TIMS-FT-ICR MS

Multiple chemical processes control how crude oil is incorporated into seawater and also the chemical reactions that occur overtime. Studying this system requires the careful preparation of the sample in order to accurately replicate the natural formation of the water-accommodated fraction that occurs in nature. Low-energy water-accommodated fractions (LEWAF) are carefully prepared by mixing crude oil and water at a set ratio. Aspirator bottles are then irradiated, and at set time points, the water is sampled and extracted using standard techniques. A second challenge is the representative characterization of the sample, which must take into consideration the chemical changes that occur over time. A targeted analysis of the aromatic fraction of the LEWAF can be performed using an atmospheric-pressure laser ionization source coupled to a custom-built trapped ion mobility spectrometry&#8211;Fourier transform&#8211;ion cyclotron resonance mass spectrometer (TIMS-FT-ICR MS). The TIMS-FT-ICR MS analysis provides high-resolution ion mobility and ultrahigh-resolution MS analysis, which further allow the identification of isomeric components by their collision cross-sections (CCS) and chemical formula. Results show that as the oil-water mixture is exposed to light, there is significant photo-solubilization of the surface oil into the water. Over time, the chemical transformation of the solubilized molecules takes place, with a decrease in the number of identifications of nitrogen- and sulfur-bearing species in favor of those with a greater oxygen content than were typically observed in the base oil.

The low-energy water-accommodated fraction (LEWAF) of crude oil is a challenging system to analyze, because over time, this complex mixture undergoes chemical transformations. This protocol illustrates methods for the preparation of the LEWAF sample and for performing photo-irradiation and chemical analysis by trapped ion mobility spectrometry&#8211;FT-ICR MS.

Analisi chimica delle frazioni acqua-ospitato di petrolio greggio fuoriuscite Utilizzando TIMS-FT-ICR MS

Multiple chemical processes control how crude oil is incorporated into seawater and also the chemical reactions that occur overtime. Studying this system ...

Ambiente

Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS

Different sulfur isotope compositions of authigenic pyrite typically result from the sulfate-driven anaerobic oxidation of methane (SO4-AOM) and organiclastic sulfate reduction (OSR) in marine sediments. However, unravelling the complex pyritization sequence is a challenge because of the coexistence of different sequentially formed pyrite phases. This manuscript describes a sample preparation procedure that enables the use of secondary ion mass spectroscopy (SIMS) to obtain in situ &#948;34S values of various pyrite generations. This allows researchers to constrain how SO4-AOM affects pyritization in methane-bearing sediments. SIMS analysis revealed an extreme range in &#948;34S values, spanning from -41.6 to +114.8&#8240;, which is much wider than the range of &#948;34S values obtained by the traditional bulk sulfur isotope analysis of the same samples. Pyrite in the shallow sediment mainly consists of 34S-depleted framboids, suggesting early diagenetic formation by OSR. Deeper in the sediment, more pyrite occurs as overgrowths and euhedral crystals, which display much higher SIMS &#948;34S values than the framboids. Such 34S-enriched pyrite is related to enhanced SO4-AOM at the sulfate-methane transition zone, postdating OSR. High-resolution in situ SIMS sulfur isotope analyses allow for the reconstruction of the pyritization processes, which cannot be resolved by bulk sulfur isotope analysis.

Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS

Analyses of the sulfur isotopic composition (&#948;34S) of pyrite from methane-bearing sediments have typically focused on bulk samples. Here, we applied secondary ion mass spectroscopy to analyze the &#948;34S values of various pyrite generations to understand the diagenetic history of pyritization.

Preparazione di pirite Autigenesi da sedimenti di metano-cuscinetto per In Situ l'analisi di isotopi di zolfo utilizzando SIMS

Different sulfur isotope compositions of authigenic pyrite typically result from the sulfate-driven anaerobic oxidation of methane (SO4-AOM) and ...

On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes

The shift to heavy crude oils and the use of alternative fossil resources such as shale oil are a challenge for the petrochemical industry. The composition of heavy crude oils and shale oils varies substantially depending on the origin of the mixture. In particular they contain an increased amount of nitrogen containing compounds compared to the conventionally used sweet crude oils. As nitrogen compounds have an influence on the operation of thermal processes occurring in coker units and steam crackers, and as some species are considered as environmentally hazardous, a detailed analysis of the reactions involving nitrogen containing compounds under pyrolysis conditions provides valuable information. Therefore a novel method has been developed and validated with a feedstock containing a high nitrogen content, i.e., a shale oil. First, the feed was characterized offline by comprehensive two-dimensional gas chromatography (GC &#215; GC) coupled with a nitrogen chemiluminescence detector (NCD). In a second step the on-line analysis method was developed and tested on a steam cracking pilot plant by feeding pyridine dissolved in heptane. The former being a representative compound for one of the most abundant classes of compounds present in shale oil. The composition of the reactor effluent was determined via an in-house developed automated sampling system followed by immediate injection of the sample on a GC &#215; GC coupled with a time-of-flight mass spectrometer (TOF-MS), flame ionization detector (FID) and NCD. A novel method for quantitative analysis of nitrogen containing compounds using NCD and 2-chloropyridine as an internal standard has been developed and demonstrated.

A method combining comprehensive two-dimensional gas chromatography with nitrogen chemiluminescence detection has been developed and applied to on-line analysis of nitrogen containing compounds in a complex hydrocarbon matrix.

Analisi on-line dei composti contenenti azoto in matrici idrocarburi complessi

The shift to heavy crude oils and the use of alternative fossil resources such as shale oil are a challenge for the petrochemical industry. The ...

Seawater Sampling and Collection

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses. For today's demonstration samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. An A-frame derrick, with a multi-purpose winch and cable system, is used in combination with Niskin or Go-Flo water sampling bottles. Conductivity, Temperature, and Depth (CTD) sensors are also used to sample the underlying water mass. To minimize outgassing, trace gas samples are collected first.  Then, nutrients, water chemistry, and cell counts are determined. Finally, waters are collected for biomass filtration. The set-up and collection time for a single cast is ~1.5 hours at a maximum depth of 215 meters. Therefore, a total of 6 hours is generally needed to complete the collection series described here.

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses.

Campionamento di acqua di mare e di raccolta

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass ...

Biologia

<meta charset="utf8"></head><body>Una configurazione pratica ed economica per misurare il metano in campioni acquosi

Measuring Dissolved Methane in Aquatic Ecosystems Using An Optical Spectroscopy Gas Analyzer

Measuring greenhouse gas (GHG) fluxes and pools in ecosystems are becoming increasingly common in ecological studies due to their relevance to climate change. With it, the need for analytical platforms adaptable to measuring different pools and fluxes within research groups also grows. This study aims to develop a procedure to use portable optical spectroscopy-based gas analyzers, originally designed and marketed for gas flux measurements, to measure GHG concentrations in aqueous samples. The protocol involves the traditional headspace equilibration technique followed by the injection of a headspace gas subsample into a chamber connected through a closed loop to the inlet and outlet ports of the gas analyzer. The chamber is fabricated from a generic mason jar and simple laboratory supplies, and it is an ideal solution for samples that may require pre-injection dilution. Methane concentrations measured with the chamber are tightly correlated (r2 &#62; 0.98) with concentrations determined separately through gas chromatography-flame ionization detection (GC-FID) on subsamples from the same vials. The procedure is particularly relevant for field studies in remote areas where chromatography equipment and supplies are not readily available, offering a practical, cheaper, and more efficient solution for measuring methane and other dissolved greenhouse gas concentrations in aquatic systems.

<meta charset="utf8"></head><body>Misurazione del metano disciolto negli ecosistemi acquatici utilizzando un analizzatore di gas per spettroscopia ottica

This study demonstrates an approach to measure methane gas concentrations in aqueous samples using portable optical analyzers coupled to an injection chamber in a closed loop. The results are similar to conventional gas chromatography, presenting a practical and low-cost alternative particularly suitable for remote field studies.

Misurazione del metano disciolto negli ecosistemi acquatici utilizzando un analizzatore di gas per spettroscopia ottica

Measuring greenhouse gas (GHG) fluxes and pools in ecosystems are becoming increasingly common in ecological studies due to their relevance to climate ...

Qualitative Characterization of the Aqueous Fraction from Hydrothermal Liquefaction of Algae Using 2D Gas Chromatography with Time-of-flight Mass Spectrometry

Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in complex mixtures. It is often used to analyze gasoline, jet fuel, diesel, bio-diesel and the organic fraction of bio-crude/bio-oil. In most of those analyses, the first dimension of separation is non-polar, followed by a polar separation. The aqueous fractions of bio-crude and other aqueous samples from biofuels production have been examined with similar column combinations. However, sample preparation techniques such as derivatization, solvent extraction, and solid-phase extraction were necessary prior to analysis. In this study, aqueous fractions obtained from the hydrothermal liquefaction of algae were characterized by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry without prior sample preparation techniques using a polar separation in the first dimension followed by a non-polar separation in the second. Two-dimensional plots from this analysis were compared with those obtained from the more traditional column configuration. Results from qualitative characterization of the aqueous fractions of algal bio-crude are discussed in detail. The advantages of using a polar separation followed by a non-polar separation for characterization of organics in aqueous samples by two-dimensional gas chromatography coupled with time-of-flight mass spectrometry are highlighted.

A two-dimensional gas chromatography-time-of-flight mass spectrometry method is described for characterization of the aqueous fraction of bio-crude produced from hydrothermal liquefaction of algae. This protocol can also be employed to analyze the aqueous fraction of liquid products from fast pyrolysis, catalytic fast pyrolysis, catalytic deoxygenation and hydro-treating.

Caratterizzazione qualitativa della frazione acquosa da idrotermale Liquefazione di alghe Utilizzando 2D gascromatografia con tempo di volo spettrometria di massa

Two-dimensional gas chromatography coupled with time-of-flight mass spectrometry is a powerful tool for identifying and quantifying chemical components in ...

Misurazione di H

Riepilogo

Esplora Altri Video

Quantitativa Rilevamento di Trace vapori esplosivi di temperatura programmata Desorption Gas Detector cattura cromatografia-Electron

Enzimatica decarbossilazione Luce-driven

Analisi chimica delle frazioni acqua-ospitato di petrolio greggio fuoriuscite Utilizzando TIMS-FT-ICR MS

Preparazione di pirite Autigenesi da sedimenti di metano-cuscinetto per In Situ l'analisi di isotopi di zolfo utilizzando SIMS

Analisi on-line dei composti contenenti azoto in matrici idrocarburi complessi

Campionamento di acqua di mare e di raccolta

Misurazione del metano disciolto negli ecosistemi acquatici utilizzando un analizzatore di gas per spettroscopia ottica

Misurazione del metano disciolto negli ecosistemi acquatici utilizzando un analizzatore di gas per spettroscopia ottica

Misurazione del metano disciolto negli ecosistemi acquatici utilizzando un analizzatore di gas per spettroscopia ottica

Caratterizzazione qualitativa della frazione acquosa da idrotermale Liquefazione di alghe Utilizzando 2D gascromatografia con tempo di volo spettrometria di massa