The structural characterization of two new, unusual kaurene diterpenes isolated from roots of Erythroxylum barbatum is described. 1D NMR and several 2D shift-correlated NMR pulse sequences (1H,1H-COSY, HMQC, HMBC and NOESY) were used for structure elucidation and the unambiguous 1H and 13C chemical shifts assignments. Single crystal X-ray diffraction analysis was also used to confirm the final relative configuration of the compounds possessing the C-20 methyl and the CH2-15 methylene groups in cis-orientation.
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http://dx.doi.org/10.1002/mrc.1700 | DOI Listing |
J Org Chem
December 2024
Department of Pharmacy, The First Affiliated Hospital, Jinan University, Guangzhou 510630, China.
Nine new structurally diverse filicinic acid-based meroterpenoids (-) with four kinds of carbon skeletons were isolated from the rhizomes of . Their structures, including the absolute configurations, were elucidated by comprehensive analysis of spectroscopic data, quantum chemical calculations, and single-crystal X-ray diffraction. Structurally, compounds - feature an unprecedented 6/6/5/6/6/6 hexacyclic system with a rare oxaspiro[4.
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University, Harbin, Heilongjiang, 150025, China.
Lithium-sulfur batteries (LSBs) offer high energy density and environmental benefits hampered by the shuttle effect related to sluggish redox reactions of long-chain lithium polysulfides (LiPSs). However, the fashion modification of the d-band center in separators is still ineffective, wherein the mechanism understanding always relies on theoretical calculations. This study visibly probed the evolution of the Co 3d-band center during charge and discharge using advanced inverse photoemission spectroscopy/ultraviolet photoemission spectroscopy (IPES/UPS), which offers reliable evidence and are consistent well with theoretical calculations.
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December 2024
Department of Engineering, Norfolk State University, Norfolk, USA.
We report a controlled deposition process using atmospheric plasma to fabricate silver nanoparticle (AgNP) structures on polydimethylsiloxane (PDMS) substrates, essential for stretchable electronic circuits in wearable devices. This technique ensures precise printing of conductive structures using nanoparticles as precursors, while the relationship between crystallinity and plasma treatment is established through X-ray diffraction (XRD) analysis. The XRD studies provide insights into the effects of plasma parameters on the structural integrity and adhesion of AgNP patterns, enhancing our understanding of substrate stretchability and bendability.
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December 2024
Qatar Environment and Energy Research Institute (QEERI), Hamad Bin Khalifa University (HBKU), Qatar Foundation, Doha, 34110, Qatar.
This study aims to modify raw zeolite with metal oxide nanocomposites to remove nickel (Ni) ions from synthetic wastewater. Novel zeolite-doped magnesium oxide (MgO), iron oxide (FeO), and zinc oxide (ZnO) nanocomposites were synthesized by hydrothermal-calcination methods. The novel zeolite-doped metal oxide nanocomposites were used as adsorbents to remove Ni (II) ions from synthetic wastewater.
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December 2024
School of Physics and Materials Science, Shoolini University, Solan, H.P., India.
The industrial sector faces a significant challenge in finding the highly effective and efficient treatments for harmful dye-based color effluents. In this study, pure and cobalt doped barium hexaferrite of chemical formula, BaCoFeO (x = 0-0.06) are made via sol-gel auto-combustion (SC) methodology.
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