Handbook of GC/MS

Hübschmann, Hans‐Joachim

doi:10.1002/9783527625215

Cited by 38 publications

(17 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…15–19 However, for mixtures of closely related isomers or polymer structures, overlapping of 1 H NMR or 13 C NMR signals often occurs, complicating the identification of important side products of the reaction mixture. The combination of organic separation techniques and two-dimensional NMR (based on homonuclear and heteronuclear correlations) are effective in resolving the issues associated with overlapping signals.…”

Section: Introductionmentioning

confidence: 99%

Elucidation of Diels–Alder Reaction Network of 2,5-Dimethylfuran and Ethylene on HY Zeolite Catalyst

et al. 2012

View full text Add to dashboard Cite

The reaction of 2,5-dimethylfuran and ethylene to produce p-xylene represents a potentially important route for the conversion of biomass to high-value organic chemicals. Current preparation methods suffer from low selectivity and produce a number of byproducts. Using modern separation and analytical techniques, the structure of many of the byproducts produced in this reaction when HY zeolite is employed as a catalyst has been identified. From these data, a detailed reaction network is proposed demonstrating that hydrolysis and electrophilic alkylation reactions compete with the desired Diels-Alder/dehydration sequence. This information will allow the rational identification of more selective catalysts and more selective reaction conditions.

show abstract

Section: Introductionmentioning

confidence: 99%

Elucidation of Diels–Alder Reaction Network of 2,5-Dimethylfuran and Ethylene on HY Zeolite Catalyst

et al. 2012

View full text Add to dashboard Cite

show abstract

“…The deconvolution method was optimised to minimise over-deconvolution, (AnalyzerPro software method parameters were: minimum peak area value, = 200, S/N= 3, width of peak = 0.01 and smoothing factor=3). The extracted features were aligned using Kovats retention indexing (AnalyzerPro Spectral Works, UK) 23 , and clustered using the VOCCluster algorithm 24 that assigned a unique identifier in the form of (ERI-m/z1 -m/z2 -m/z3 -m/z4 -m/z5) to each VOC isolated and grouped from the 245 samples; ERI indicated the retention index for the VOC environmentalfeature and m/z1… m/zn were the nominal masses of the compound's ion fragments in decreasing order of abundance needed to uniquely define the deconvolved VOC features within the data-cube. The resultant sorted, and grouped features were consolidated into an environmental-VOC-data matrix that contained the extracted peak areas for each of the features isolated from each room-air sample.…”

Section: Data Processingmentioning

confidence: 99%

The Variability of Volatile Organic Compounds in Clinical Environments

Salman

Ibrahim

Kanabar

et al. 2021

Preprint

View full text Add to dashboard Cite

The development of clinical breath-analysis is confounded by the variability of background volatile organic compounds (VOC). Interpretation of clinical breath-data at individual, and cohort levels requires characterisation of clinical-VOC levels and exposures. Active-sampling with thermal-desorption/gas chromatography-mass spectrometry recorded and evaluated VOC concentrations in 245 samples of indoor air from three sites in a large NHS provider trust in the UK over 27 months. 7344 clinical VOC were isolated and 328 VOC and 68 were observed in more than 5% and 30% of samples respectively; associated with exogenous and endogenous sources. 17 VOC were seasonal differentiators. Metabolites from the anaesthetic sevoflurane, and putative-disease biomarkers in room air indicated that exhaled VOC were a source of background-pollution in clinical breath-tests. Apart from solvents, and PPE-waxes, exhaled VOC concentrations above 3 µgm-3 are unlikely to arise from room air contamination. This level could be applied as a threshold for inclusion in studies.

show abstract

“…Helium (99.999%) was used as carrier gas at 1.200 and 1.600 mL/min constant flow for GC-MS and GC-O-MS, respectively. The GC-MS and GC-O-MS analysis methods referenced in our previous work were used with some modifications [10,22].…”

Section: Gc-ms and Gc-o-ms Analysismentioning

confidence: 99%

Characterization of the Key Aroma Compounds in Traditional Hunan Smoke-Cured Pork Leg (Larou, THSL) by Aroma Extract Dilution Analysis (AEDA), Odor Activity Value (OAV), and Sensory Evaluation Experiments

Zhang

et al. 2020

Foods

View full text Add to dashboard Cite

The key aroma compounds in smoke-cured pork leg were characterized by gas chromatography–olfactometry coupled with aroma extract dilution analysis (GC–O/AEDA), odor activity value (OAV), recombination modeling, and omission tests. Ranking analysis showed that pork leg smoke-cured for 18 days had the best sensory qualities, with strong meaty, smoky, roasty, woody, and greasy attributes. Thirty-nine aroma-active regions with flavor dilution (FD) factors ranging from 9 to 6561 were detected. Overall, 3-ethylphenol had the highest FD factor of 6561, followed by 2,6-dimethoxyphenol, 3,4-dimethylphenol, 4-ethylguaiacol, 4-methylguaiacol, 3-methylphenol, and 2-acetyl-1-pyrroline, with FD ≥243. Among 39 aroma compounds, 27 compounds with OAVs ≥1 and were potent odorants. A similarity of 90.73% between the recombination model and traditional Hunan Smoke-cured Pork Leg (THSL) sample was obtained. Omission tests further confirmed that (E)-2-nonenal, 2-methoxy-4-vinylphenol, guaiacol, 3-ethylphenol, 2,6-dimethylphenol, 2-acetyl-1-pyrroline, and methional were key odorants in smoke-cured pork leg. Additionally, 2-acetyl-1-pyrroline (38.88 μg/kg), which contributes to a roasty aroma, was characterized here as a key odorant of smoke-cured pork leg for the first time.

show abstract

Handbook of GC/MS

Cited by 38 publications

References 0 publications

Elucidation of Diels–Alder Reaction Network of 2,5-Dimethylfuran and Ethylene on HY Zeolite Catalyst

Elucidation of Diels–Alder Reaction Network of 2,5-Dimethylfuran and Ethylene on HY Zeolite Catalyst

The Variability of Volatile Organic Compounds in Clinical Environments

Characterization of the Key Aroma Compounds in Traditional Hunan Smoke-Cured Pork Leg (Larou, THSL) by Aroma Extract Dilution Analysis (AEDA), Odor Activity Value (OAV), and Sensory Evaluation Experiments

Contact Info

Product

Resources

About