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991.
Castillo-Rodriguez Judith Pereyra Carlos Javier Valente Paulo Seré Andrés Marotti Ricardo E. Hevia Samuel A. Dalchiele Enrique A. del Rio Quero Rodrigo 《Journal of Solid State Electrochemistry》2020,24(4):797-808
Journal of Solid State Electrochemistry - Transparent conductive oxide electrodes and specifically SnO2:F/glass are widely employed substrates in the preparation of optoelectronic devices. This... 相似文献
992.
Dr. Giovanny Carvalho dos Santos Juan Carlos Roldao Dr. Junqing Shi Dr. Begoña Milián-Medina Prof. Dr. Luiz Carlos da Silva-Filho Dr. Johannes Gierschner 《Chemphyschem》2020,21(16):1797-1804
A combined spectroscopic and TD-DFT case study was performed, to identify a robust method to calculate the complex near UV/Vis absorption spectra of various amino- vs. nitro-substituted 2,4-diphenylquinolines, which vary strongly under neutral and successively acidic conditions. For this, different DFT functionals were tested for geometry optimization and the TD part to calculate the neutral and different protonated species in a fast screening approach, i. e. using single point calculations in an implicit solvent. Offset-corrected M06HF, hitherto only applied to polymers, was identified as a suitable method to reproduce the absorption spectra in a reasonable fashion for all different substitution pattern and all different protonated species at different pH values; moreover, the method properly predicts the energetic ordering of low-lying n-π* and ππ* transitions, which is decisive for the non-/emissive nature of the different compounds. In all, this might provide a valuable tool for computer-aided design of related classes of compounds. 相似文献
993.
994.
Dr. Mariane Le Fur Nicholas J. Rotile Carlos Correcher Dr. Veronica Clavijo Jordan Alana W. Ross Prof. Ciprian Catana Prof. Peter Caravan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(4):1490-1494
Gadolinium-based contrast agents (GBCAs) are used to provide diagnostic information in clinical magnetic resonance (MR) examinations. Gadolinium (Gd) has been detected in the brain, bone and skin of patients, months and years following GBCA administration, raising concerns about long term toxicity. Despite increased scrutiny, the concentration, chemical form and fate of the retained gadolinium species remain unknown. Importantly, the whole body biodistribution and organ clearance of GBCAs is poorly understood in humans. Gadolinium lacks suitable isotopes for nuclear imaging. We demonstrate that the yttrium-86 isotope can be used as a gadolinium surrogate. We show that Gd and their analogous Y complexes have similar properties both in solution and in vivo, and that yttrium-86 PET can be used to track the biodistribution of GBCAs over a two-day period. 相似文献
995.
Cyrille Charpentier Jérémy Salaam Dr. Aline Nonat Fabio Carniato Dr. Olivier Jeannin Dr. Isabel Brandariz Dr. David Esteban-Gomez Dr. Carlos Platas-Iglesias Dr. Loïc J. Charbonnière Prof. Mauro Botta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(24):5407-5418
The heptadentate ligand L was shown to form an extremely stable Gd complex at neutral pH with a pGd value of 18.4 at pH 7.4. The X-ray crystal structures of the complexes formed with Gd and Tb displayed two very different coordination behaviors being, respectively, octa- and nonacoordinated. The relaxometric properties of the Gd complex were studied by field-dependent relaxivity measurements at various temperatures and by 17O NMR spectroscopy. The pH-dependence of the longitudinal relaxivity profile indicated large changes around neutral pH leading to a very large value of 10.1 mm −1⋅s−1 (60 MHz, 298 K) at pH 4.7. The changes were attributed to an increase of the hydration number from one water molecule in basic conditions to two at acidic pH. A similar trend was observed for the luminescence of the Eu complex, confirming the change in hydration state. DOSY experiments were performed on the Lu analogue, pointing to the absence of dimers in solution in the considered pH range. A breathing mode of the complex was postulated, which was further supported by 1H and 31P NMR spectroscopy of the Yb complex at varying pH and was finally modeled by DFT calculations. 相似文献
996.
Ruzzarin Anelise Lima da Cruz Paulo Alberto de Almeida Rangel Johnny da Silva Carlos José Iwahara Akira Lopes Ricardo Tadeu 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(2):721-729
Journal of Radioanalytical and Nuclear Chemistry - A procedure for characterizing the activity amount of 125I seed was developed in order to establish a secondary standard activity measurement... 相似文献
997.
Carvalho Patricia R. Munita Casimiro S. Neves Eduardo G. Zimpel Carlos A. 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1053-1058
Journal of Radioanalytical and Nuclear Chemistry - This research aims to contribute to the discussion of ceramic objects found at the Monte Castelo shellmound, an archaeological site located at... 相似文献
998.
Arboleda Paula A. Rincón Jesús Ma. González Oliver Carlos J. R. 《Journal of Thermal Analysis and Calorimetry》2022,147(21):11715-11728
Journal of Thermal Analysis and Calorimetry - A new set of iron-uranium phosphate glasses containing (1–20) UO2.67. (10–20) Fe2O3. (55–68) P2O5 (mass/%) were melted adequately.... 相似文献
999.
Pastor-Belda Marta Arroyo-Manzanares Natalia Campillo Natalia Vias Pilar Guluarte Crystal Angulo Carlos Esteban Mara ngeles 《Chromatographia》2022,85(4):353-363
Chromatographia - Nucleobases, nucleosides and nucleotides can act as chemical markers and immunnostimulants. Ultra-high-performance liquid chromatography with electrospray ionization and... 相似文献
1000.