Carbohydrate is an important pool in the terrestrial carbon cycle. The potential offered by natural and artificial 13C-labelling techniques should therefore be applied to the investigation of the dynamics of individual sugars in soils. For this reason, we evaluated the method of 13C sugar analysis by gas chromatography/combustion/isotope-ratio mass spectrometry (GC/C/IRMS) after hydrolysis and direct trimethylsilylation. Trimethylsilylation involved the addition of several carbon atoms per sugar. These atoms have to be taken into account in the estimation of the carbon isotope ratio. The analysis of standard and natural pentoses and hexoses of known 13C enrichments revealed that the number of analysed added carbon atoms was less than expected from stoichiometry. This was attributed to incomplete derivatization and/or incomplete oxidation of methylsilyl carbon before IRMS. Using a calibration of the number of analysed added carbon atoms, the isotope excess of enriched samples could be determined with a relative error close to 5%. Concerning the determination of natural abundances by GC/C/IRMS, we could measure the delta 13C of standard C3- and C4-derived sugars with an accuracy of +/-1.5 per thousand using the previous calibration. We were able to apply this technique to plant-soil systems labelled by pulse-chase of 13CO2, revealing the nature and dynamics of sugars in the plant rhizosphere.
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http://dx.doi.org/10.1002/rcm.1269 | DOI Listing |
J Mol Model
January 2025
Department of Chemistry, Federal Institute of Education, Science and Technology of Espírito Santo, Av. Min. Salgado Filho, Vila Velha, 29106-010, Espírito Santo, Brazil.
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January 2025
College of Chemical Engineering, Fuzhou University, Fuzhou, 350116, People's Republic of China.
Context: The rotating arc plasma technique for the synthesis of nitrogen-doped graphene capitalizes on the distinctive attributes of plasma, presenting a straightforward, efficient, and catalyst-free strategy for the production of nitrogen-doped graphene. However, experimental outcomes generally fail to elucidate the atomic-level mechanism behind this process. Our research utilizes molecular dynamics simulations to explore theoretically the formation of radicals during the plasma-driven reaction between methane (CH₄) and nitrogen (N₂).
View Article and Find Full Text PDFDalton Trans
January 2025
Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
Boriranes, highly strained three-membered cyclic organoboron heterocycles, have emerged as potential synthons for the synthesis of many organoboron species. However, the synthesis of boriranes with tricoordinate, sp-hybridised boron and tetracoordinate, sp-hybridised carbon atoms is very challenging owing to their high Lewis acidity. Herein we describe the isolation of base-free triaminoboriranes from the room-temperature reaction of diaminoalkynes with an aminodistannylborane.
View Article and Find Full Text PDFSci Rep
January 2025
Materials Science and Engineering Program, College of Arts and Sciences, American University of Sharjah, POB 26666, Sharjah, United Arab Emirates.
Graphene, a two-dimensional material featuring densely packed sp-hybridized carbon atoms arranged in a honeycomb lattice, has revolutionized material science. Laser-induced graphene (LIG) represents a breakthrough method for producing graphene from both commercial and natural precursors via direct laser writing, offering advantages such as simplicity, efficiency, and cost-effectiveness. This study demonstrates a novel approach to synthesize a composite material exclusively from a porous organic polymer (POP) by direct femtosecond laser writing on a compressed imide-linked porous organic polymer substrate.
View Article and Find Full Text PDFJ Am Chem Soc
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Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education, Tsinghua University, Beijing 100084, China.
The reduction of CO mediated by transition metals has garnered significant interest, yet little is known about the reduction of CO using f-element compounds. Herein, the reduction of CO to CO by tetravalent uranium (U) compound UO is investigated via matrix isolation infrared spectroscopy and quantum chemical study. Our results reveal that a stable carbonate intermediate OUCO () can be prepared at low temperatures (4-12 K).
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