A number of linear cumulenes and heterocumulenes have been made by charge stripping of anions of known bond connectivity in the source of a mass spectrometer. Some of these reactive molecules have been identified in interstellar molecular clouds. The structures of these neutrals may be investigated by reionization to a decomposing positive ion [the neutralization-reionization technique ((-)NR(+))], and/or by ab initio calculations. Energized linear cumulenes and heterocumulenes may undergo cyclization to form stable cyclic isomers. To cite a selection of the examples described in this review: (i) four-atom systems CCCC and some heterocumulenes CCCX (X=B, N, Al, Si, P) involve the formation of stable four-membered ring rhombic (also called kite and fan) structures. One of the cyclic molecules, cyclo-C(3) Si, has been detected in interstellar molecular clouds, (ii) five-atom cumulene and heterocumulene systems are more complex. Linear CCCCC rearranges the carbon skeleton by forming a C substituted rhomboid system, CCCCO forms a three-membered cyclic isomer, while nitrogen containing five-atom cumulenes effect nitrile to isonitrile interconversion via three-centered cyclized intermediates, and (iii) CCCCCC and CCCCBO cyclize to give unique six-membered ring systems.
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Sensors (Basel)
November 2024
École Nationale Supérieure des Arts et Industries Textiles-ENSAIT, ULR 2461-GEMTEX-Génie et Matériaux Textiles, University of Lille, F-59000 Lille, France.
Women sports wearer's comfort and health are greatly impacted by the breast movements and resultant sports bra compression to prevent excessive movement. However, as sports bras are only made in universal sizes, they do not offer the right kind of support that is required for a certain activity. To prevent this issue, textile-based strain sensors may be utilized to track compression throughout various activities to create activity-specific designed sports bras.
View Article and Find Full Text PDFJ Food Sci
December 2024
Zhejiang Key Laboratory for Agri-Food Processing, Key Laboratory of Agri-Products Postharvest Handling of Ministry of Agriculture and Rural Affairs, College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China.
(E)-2-Hexenal (E2H) is an important volatile organic compound (VOC) that can serve as a marker for fruit quality sensing and shelf-life evaluation. However, visual and portable sensors for E2H have not been reported mainly because of the difficulty in selective response to E2H while avoiding interference from other VOC, especially isomers. Herein, we developed a novel colorimetric sensor based on thiol-functionalized polydiacetylene assembly (PDA-SH/PDA) for the quantitative and selectivity of E2H.
View Article and Find Full Text PDFBiogerontology
December 2024
Department of Nephrology, Institute of Kidney Diseases, West China Hospital, Sichuan University, 37 Guoxue Alley, Chengdu, 610041, China.
Carotenoids are naturally occurring pigments found in plants and certain microorganisms. Some carotenoids act as precursors to vitamin A, which is essential for various health aspects, including vision, immune function, and skin health. Carotenoids, including α-carotene, β-carotene, β-cryptoxanthin, lycopene, lutein and zeaxanthin, are known to reduce the risk of age-related diseases and promote healthy aging.
View Article and Find Full Text PDFJ Chem Theory Comput
December 2024
Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, Via Borsari 76, I-44121 Ferrara, Italy.
The use of the mutual information (MI) as a measure of the entanglement in quantum systems has gained a consensus in recent years, even if there is an ongoing effort to distinguish the classical and quantum contributions contained therein. This quantity has been first introduced in condensed matter physics, in particular, in studies based on the density matrix renormalization group method. This method has been successfully adapted to quantum chemistry problems, opening the way to compute MI also in molecular systems.
View Article and Find Full Text PDFJ Agric Food Chem
December 2024
State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, P. R. China.
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