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排序方式: 共有2172条查询结果,搜索用时 140 毫秒
1.
Ibrahim Musa Guy Raffin Marie Hangouet Marie Martin Albert Alcacer Nadia Zine Francesca Bellagambi Nicole Jaffrezic-Renault Abdelhamid Errachid 《Electroanalysis》2022,34(8):1338-1347
Thin-film composite of chitosan/nickel phthalocyanine (NiPc) was electrochemically deposited on the fingers of interdigitated gold electrodes, applying chronoamperometric polymerization technique. The presence of crystallized NiPc in the chitosan was confirmed by EDX and FTIR analysis. Acetone, ethanol, and methanol gas-sensing properties of the films prepared at optimum conditions were studied at atmospheric temperature, through differential measurements at an optimized frequency of 10 kHz, using a lock-in amplifier. The conductometric sensor presents the highest sensitivity of 60.2 μS.cm−1(v/v) for methanol and 700 ppm as the limit of detection. For validation, the methanol content of a commercial rubbing alcohol was determined. 相似文献
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Interactions of Pt‐ttpy with G‐Quadruplexes Originating from Promoter Region of the c‐myc Gene Deciphered by NMR and Gel Electrophoresis Analysis 下载免费PDF全文
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Analysis and fragmentation mechanisms of hirsutinolide‐type sesquiterpene lactones by ultra‐high‐performance liquid chromatography/electrospray ionization linear ion trap Orbitrap mass spectrometry 下载免费PDF全文
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Dr. Hiromichi Nakahara Dr. Marie Pierre Krafft Prof. Osamu Shibata 《Chemphyschem》2020,21(17):1966-1970
We found that monolayers of dipalmitoylphosphatidylcholine (DPPC) and semi-fluorinated tetrablock di(F10H16) self-assemble to form a new type of large, complex flower-like patterns on the surface of water and on solid substrates. The hierarchical organization of these unusual self-assemblies was investigated using compression and surface potential isotherms, in situ fluorescence and Brewster angle microscopies, and atomic force microscopy after transfer. 相似文献
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Marie‐Claire Giel Christopher J. Smedley Emily R. R. Mackie Taijie Guo Jiajia Dong Tatiana P. Soares da Costa John E. Moses 《Angewandte Chemie (International ed. in English)》2020,59(3):1181-1186
The boom in growth of 1,4‐disubstituted triazole products, in particular, since the early 2000’s, can be largely attributed to the birth of click chemistry and the discovery of the CuI‐catalyzed azide–alkyne cycloaddition (CuAAC). Yet the synthesis of relatively simple, albeit important, 1‐substituted‐1,2,3‐triazoles has been surprisingly more challenging. Reported here is a straightforward and scalable click‐inspired protocol for the synthesis of 1‐substituted‐1,2,3‐triazoles from organic azides and the bench stable acetylene surrogate ethenesulfonyl fluoride (ESF). The new transformation tolerates a wide selection of substrates and proceeds smoothly under metal‐free conditions to give the products in excellent yield. Under controlled acidic conditions, the 1‐substituted‐1,2,3‐triazole products undergo a Michael addition reaction with a second equivalent of ESF to give the unprecedented 1‐substituted triazolium sulfonyl fluoride salts. 相似文献
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Dr. Morten Gotthold Vinum Laura Voigt Colby Bell Dmytro Mihrin Prof. Dr. René Wugt Larsen Prof. Dr. Kensha Marie Clark Prof. Dr. Kasper S. Pedersen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(10):2143-2147
β-Diketonates, such as acetylacetonate, are amongst the most common bidentate ligands towards elements across the entire periodic table and are considered wholly redox-inactive in their complexes. Herein we show that complexation of 1,1,1,5,5,5-hexafluoroacetylacetonate (hfac−) to CrII spontaneously affords CrIII and a reduced β-diketonate radical ligand scaffold, as evidenced by crystallographic analysis, magnetic measurements, optical spectroscopy, reactivity studies, and DFT calculations. The possibility of harnessing β-diketonates as electron reservoirs opens up possibilities for new metal–ligand concerted reactivity in the ubiquitous β-diketonate coordination chemistry. 相似文献
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Myriam Drouin Dr. Parvesh Wadhwani Dr. Stephan L. Grage Dr. Jochen Bürck Dr. Johannes Reichert Sébastien Tremblay Marie Sabine Mayer Christian Diel Alexander Staub Prof. Jean-François Paquin Prof. Dr. Anne S. Ulrich 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(7):1511-1517
Solid-state 19F NMR is a powerful method to study the interactions of biologically active peptides with membranes. So far, in labelled peptides, the 19F-reporter group has always been installed on the side chain of an amino acid. Given the fact that monofluoroalkenes are non-hydrolyzable peptide bond mimics, we have synthesized a monofluoroalkene-based dipeptide isostere, Val-Ψ[(Z)-CF=CH]-Gly, and inserted it in the sequence of two well-studied antimicrobial peptides: PGLa and (KIGAKI)3 are representatives of an α-helix and a β-sheet. The conformations and biological activities of these labeled peptides were studied to assess the suitability of monofluoroalkenes for 19F NMR structure analysis. 相似文献
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