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Bucataru Ioan Constantinescu Oana Creţu Georgeta 《Annals of Global Analysis and Geometry》2022,62(4):815-827
Annals of Global Analysis and Geometry - We prove that in a Finsler manifold with vanishing $$\chi $$ -curvature (in particular with constant flag curvature) some non-Riemannian geometric... 相似文献
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Martien A. Würdemann Cristina Niţu Dr. Stefaan M. A. De Wildeman Dr. Katrien V. Bernaerts Prof. Dr. Romano V. A. Orru 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(36):8090-8100
Pyrazines are an underreported class of N-heterocycles available from nitrogen-rich biomass presenting an interesting functional alternative for current aromatics. In this work, access to pyrazines obtained from amino acids by using the 90 year old Dakin–West reaction was explored. After a qualitative screening several functional proteinogenic amino acids proved good substrates for this reaction, which were successfully scaled to multigram scale synthesis of the corresponding intermediate α-acetamido ketones. Subsequently, the conditions towards pyrazine formation using δ-amino-levulinic acid were optimized, and these were employed to synthesize a relevant set of five functional dimethylpyrazines in high purity. These pyrazines can be considered a versatile toolbox of aromatic building blocks for a wide range of applications, such as in the synthesis of polymers or metal–organic frameworks. 相似文献
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Lucas Ueberricke Ioana Ciubotaru Farhad Ghalami Felix Mildner Dr. Frank Rominger Prof. Dr. Marcus Elstner Prof. Dr. Michael Mastalerz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(50):11634-11642
Five di- and tetracyano-substituted pyrene-fused pyrazaacenes were synthesized and studied as potential electron acceptors in the solid state. Single crystals of all compounds were grown and the crystal packing studied by DFT calculations (transfer integrals and reorganization energies) to get insight into possible use for semiconducting charge transport. 相似文献
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Alexandra Belcovici Carmen Ioana Fort Laura Elena Mureşan Ioana Perhaiţa Gheorge Borodi Graziella Liana Turdean 《Electroanalysis》2023,35(5):e202200395
ZnO nanoparticles (ZnO-NP) were prepared by a facile precipitation technique using di-isopropyl amine as precipitating agent. The morpho-structure and porosity of the as-prepared nano-powder were investigated by FT-IR analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), and BET analysis. By drop-casting, a composite film was deposited to obtain ZnO-NP-Nafion/GCE modified electrode. The modified electrode was investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and square wave anodic stripping voltammetry (SWASV) for the detection of Pb2+, Cd2+, Cu2+, and Fe3+, and it was successfully applied for the detection of Pb2+ and Cu2+ in real water samples. 相似文献
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