The preparation conditions of silica monoliths for gas chromatography were investigated. Silica-based monolithic capillary columns based on sol-gel process were tested in the course of high-speed gas chromatographic separations of light hydrocarbons mixture (C1-C4). The impact of modifying the amount of porogen and/or catalyst on the monolith properties were studied. At the best precursor/catalyst/porogen ratio evaluated, a column efficiency of about 6500 theoretical plates per meter was reached with a very good resolution (4.3) for very light compounds (C1-C2). The test mixture was baseline separated on a 70cm column. To our knowledge for the first time a silica-based monolithic capillary column was able to separate light hydrocarbons from methane to n-butane at room temperature with a back pressure in the range of gas chromatography facilities (under 4.1bar).
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http://dx.doi.org/10.1016/j.chroma.2015.01.012 | DOI Listing |
Environ Sci Pollut Res Int
December 2024
Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871, Frederiksberg C, Denmark.
Environmental consequences of petroleum mulch application are crucial in regions prone to wind erosion and desertification. This study aimed to assess the long-term effects of petroleum mulching on soil polycyclic aromatic hydrocarbon (PAH) concentrations and the associated human and ecological risk indices. These indices include incremental lifetime cancer risk (ILCR), hazard index (HI), toxic equivalent concentration (TEQ), toxic unit (TU), and risk quotient (RQ) in soil samples from Khuzestan province, Iran.
View Article and Find Full Text PDFJ Sci Food Agric
December 2024
Faculty of Veterinary Medicine Department of Biochemistry, Ondokuz Mayis University, Samsun, Turkey.
Background: The present study aimed to comprehensively evaluate the anticancer, anti-inflammatory, and antioxidant properties of Globularia cordifolia L.
Samples: The plant material was collected and extracted using the maceration method. Antioxidant activities were assessed through DPPH (i.
Sci Rep
December 2024
Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 22452, Riyadh, 11495, Saudi Arabia.
Rhazya stricta, a perennial shrub native to the Middle East and South Asia, has been used in traditional medicine for various therapeutic purposes, including antimicrobial action. The current study aimed to compare the antifungal properties of 96% and 50% ethanolic extracts of R. stricta leaves and their biogenic silver nanoparticles (AgNPs).
View Article and Find Full Text PDFSci Rep
December 2024
Department of Intensive Care Unit, The 940 Hospital of Joint Logistics Support Force of Chinese PLA, Lanzhou, China.
High-altitude pulmonary edema (HAPE) is a life-threatening altitude sickness afflicting certain individuals after rapid ascent to high altitude above 2500 m. In the setting of HAPE, an early diagnosis is critical and currently based on clinical evaluation. The aim of this study was to utilize the metabolomics to identify the altered metabolic patterns and potential biomarkers for HAPE.
View Article and Find Full Text PDFSci Rep
December 2024
Metanotitia Inc, Building C4, Science and Technology Innovation Headquarters, Shenzhen (Harbin) Industrial Park, 288 Zhigu Street, Songbei District, Harbin, 150029, China.
Dried blood spot (DBS) sampling offers significant advantages over conventional blood collection methods, such as reduced sample volume, minimal invasiveness, suitability for home-based sampling, and ease of transport. However, understanding the effects of variable storage temperatures and times on metabolite stability is crucial due to varying intervals and delivery conditions between sample collection and metabolomics analysis. To minimize biological variances, all samples were collected from the same individual simultaneously and stored at three different temperatures (4 °C, 25 °C, and 40 °C) for diverse time points (3, 7, 14, and 21 days).
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