13,243 research outputs found
Generic Software Frameworks for GC-MS Based Metabolomics
No full textHoffmann N, Stoye J. Generic Software Frameworks for GC-MS Based Metabolomics. In: Roessner U, ed. Metabolomics. InTech; 2012: 73-98
New performing GC columns with unmatched separation capabilities
No full textGas chromatography (GC) is widely used for qualitative and quantitative analysis in numerous fields, such as petroleum, chemical industry, agriculture, environmental protection, medicine, and so on, due to its high
versatility, high selectivity, simplicity of use, analysis speed, and low sample consumption. The column is the heart of a GC instrumentation, which allows the analyte separation and their recognition and quantification. Commercial columns do not always allow a complete peak separation when compounds (i.e., isomers) are very
similar in molecular weight, polarity, and vapor pressure. The choice of the correct stationary phase, with high selectivity towards target analytes, is the key to obtaining the required chromatographic separation and the subsequent qualitative and quantitative analysis.
Considering the rapid polymer science development and the growing demand for new columns with
improved resolution capabilities, in this work novel stationary phases for capillary GC have been designed, synthesized, and characterized in terms of polarity range, resolution, column efficiency, thermal stability, filmforming properties, and support-deactivating capacity1-5. The separation features of these novel stationary phases allow high-resolution performances for a wide range of compounds, like aromatic anilines, xylenes, aromatic amines, halogenated benzenes, and aromatic aldehydes, with marked capabilities toward isomer separations.References:
[1] T. Sun, M. Ba, Y. Song, W. Li, Y. Zhang, Z. Cai, S. Hu, X. Liu, D. Nardiello, M. Quinto, Analytica Chimica Acta, 2024, 1291, art. no. 342221.
[2] T. Sun, R. Chen, Q. Huang, M. Ba, Z. Cai, H. Chen, Y. Qi, H. Chen, X. Liu, D. Nardiello, M. Quinto, Analytica
Chimica Acta, 2023, 1251, art. no. 340979.
[3] T. Sun, R. Chen, Q. Huang, M. Ba, Z. Cai, S. Hu, X. Liu, D. Nardiello, M. Quinto, ACS Applied Materials and Interfaces, 2022, 14 50, pp. 56132-56142
[4] R. Chen, Z. Cai, W. Li, Q. Huang, D. Nardiello, M. Quinto, X. Liu, S. Hu, T. Sun, Chemistry and Biodiversity, 2022,
19, art. no. e202200829
[5] Q. Huang, Z. Cai, R. Chen, W. Zhang, D. Nardiello, M. Quinto, X. Liu, S. Hu, T. Sun, Microchemical Journal, 2022,
183, art. no. 10808
DETERMINATION OF DISSOLVED-OXYGEN IN SEAWATER BY DIRECT SPECTROPHOTOMETRY OF TOTAL IODINE
No full textPREDICTION OF NITRATE CONCENTRATION FROM 2 END-MEMBER MIXING IN THE SOUTHERN EAST-CHINA-SEA
No full textGC-FID data of biocatalytic esterification reactions & NMR data of lignin characterization
No full textTabulated chromatographic data (GC-FID) from butyl butyrate esterification reactions. 13C and 31P NMR data from pine kraft lignin (BIOPIVA 100) and cationic pine kraft lignin. A list of sample code identifiers with their descriptions is available upon request from the author.<br
A study on volatile metabolites screening by HS-SPME-GC-MS and HS-GC-IMS for discrimination and characterization of white and yellowed rice
No full textStrappe, P ORCiD: 0000-0003-0100-0558Background and objectives: Yellowed rice results in serious economic losses to grain industry. This study attempted to profile the volatile metabolites in before- and after-yellowing rice of five Chinese common rice cultivars. Application untargeted metabolomics approach to discover the biomarkers in yellowed rice. Findings: The volatile metabolites were detected by headspace-gas chromatography–ion mobility spectrometry (HS-GC-IMS) and headspace solid-phase microextraction–gas chromatography-mass spectrometry (HS-SPME-GC-MS). Yellowed rice emitted more aldehydes, alcohols, furan, and less ester than white rice. Partial least squares-discriminant analysis (PLS-DA) based on GC-MS and GC-IMS data was revealed a good classifying tool for white and yellowed rice. Hexanal, nonanal, octanal, 1-pentanol, and 2-pentyl-furan were selected as the potential markers by the variable importance in projection (VIP) variable selection method. All of these markers were associated with fatty acid oxygenation. Conclusions: Comparative analysis and biomarker identification of the volatile metabolites of different cultivars of Chinese yellowed rice lay a foundation for research on yellowing mechanism. Significance and novelty: The results of the current study provide a useful basis in the rice yellowing mechanism study. Additionally, a rapid rice aroma analysis method using GC-IMS was developed. So in the future, yellowed rapid reorganization GC-IMS technology could be a preferred choice. © 2020 Cereals & Grains Associatio
GC-MS fingerprints of 20 batches of Schizonepetae Spica samples and reference chromatogram (R).
No full textGC-MS fingerprints of 20 batches of Schizonepetae Spica samples and reference chromatogram (R).</p
The Private Cost of Long-Term Care in Canada: Where You Live Matters
No full textCanadians expect the same access to health care whether they are rich or poor, and wherever they live, often without direct charge at the point of service. However, we find that the private cost of long-term care differs greatly across the country, and within provinces, we find substantial variation, depending on income level, marital status, and, in Quebec alone, on assets owned. A non-married person with average income would pay more than twice as much in the Atlantic provinces as in Quebec, while a couple with one in care would pay almost four times as much in Newfoundland as in Alberta.long-term care, private cost
Effect of biodegradation on the molecular composition and structure of asphaltenes: Clues from quantitative Py-GC and THM-GC
No full textThere is an on-going debate about whether asphaltenes can be anaerobically biodegraded in reservoir rocks due to their complex macromolecular structure. In this study, asphaltenes were precipitated from a sequence of bitumens at various degrees of biodegradation. The compositions of alkyl moieties within the asphaltene molecular structure were characterized by on-line flash pyrolysis-gas chromatography (Py-GC), on-line thermally assisted hydrolysis and methylation using tetramethylammonium hydroxide (THM-GC), and Py-GC combined with alkaline hydrolysis. The results indicate that alkyl moieties bonded to asphaltene macromolecules are dominated by linear structures with chain lengths up to C-27, mainly bonded through C-C and ether (thioether) bonds but less so through ester and hydrogen bonds. Furthermore, most n-fatty acids and linear aliphatic alcohols bonded to asphaltene structure by ester and hydrogen bonds were altered at slight-moderate biodegradation stages, while linear alkyl moieties attached to the asphaltene core through C-C and ether (thioether) bonds were likely altered at heavy-severe biodegradation stages. This indicates that the linear alkyl moieties bonded to the asphaltene structure by hydrogen and ester bonds are more susceptible to biodegradation than those bonded to the asphaltene core through stronger covalent bonds such as C-C and ether (thioether) bonds. Furthermore, variations in the chemical compositions and molecular structure of asphaltenes during biodegradation may not only be attributed to the alteration of linear alkyl moieties, but also the replacement of linear alkyl moieties bonded to the asphaltene structure by hydrogen and ester bonds with other biodegradation products. (C) 2015 Elsevier Ltd. All rights reserved
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