Publisher Correction: Hydrogen-rich supernovae beyond the neutrino-driven core-collapse paradigm

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Solution chemistry of uranyl ion with iminodiacetate and oxydiacetate : a combined NMR/EXAFS and potentiometry/calorimetry study

The solution chemistry of uranyl ion with iminodiacetate (IDA) and oxydiacetate (ODA) was investigated using NMR and EXAFS spectroscopies, potentiometry, and calorimetry. From the NMR and EXAFS data and depending on stoichiometry and pH, three types of metal:ligand complex were identified in solution in the pH range 3-7: 1:1 and 1:2 monomers; a 2:2 dimer. From NMR and EXAFS data for the IDA system and previous studies, we propose the three complex types are [UO2(IDA)(H2O)2], [UO2(IDA)2]2-, and [(UO2)2(IDA)2(μ-OH) 2]2-. From EXAFS spectroscopy, similar 1:1, 2:2, and 1:2 complexes are found for the ODA system, although 13C NMR spectroscopy was not a useful probe in this system. For the 1:1 and 1:2 complexes in solution, EXAFS spectroscopy is ambiguous because the data can be fitted with either a long U-N/Oether value (ca. 2.9 Å) suggesting 1,7-coordination of the ligand or a U-C interaction at a similar distance, consistent with terminal bidentate coordination. However, the NMR data of the IDA system suggest that 1,7-coordination is the more likely. The stability constants of the three complexes were determined by potentiometric titrations; the log β values are 9.90 ± 0.09 0.08, 16.42 ± 0.21 0.14, and 10.80 ± 0.22 0.15 for the 1:1, 1:2 and 2:2 uranyl-IDA complexes, respectively, and 5.77 ± 0.36 0.20, 7.84 ± 0.63 0.28, and 4.29 ± 0.90 0.27 for the 1:1, 1:2, and 2:2 uranyl-ODA complexes, respectively. The thermodynamic constants for the complexes were calculated from calorimetric titrations; the enthalpy changes (kJ mol-1) and entropy changes (J K-1 mol-1) of complexation for the 1:1, 1:2, and 2:2 complexes respectively are the following. IDA: 12 ± 2, 230 ± 8; 8 ± 2, 151 ± 9; -33 ± 3, -283 ± 11. ODA: 26 ± 2, 198 ± 12; 20 ± 2, 106 ± 8; -24 ± 2; -219 ± 8

Characterization of ETL 9357FLA photomultiplier tubes for cryogenic temperature applications

We carried out a careful evaluation of the performance of the large cathode area ETL 9357FLA photomultiplier tube operating at cryogenic temperature. The measurements were focused on evaluating the parameters which mainly characterize the operating performances of the device down to 77 K and the spread of the distinctive features over 54 samples assembled in the ICARUS apparatus. The results that we obtained demonstrate that the photomultiplier is suited for light detection in such unconventional operating conditions, certifying this device for the direct measurement of scintillation light coming from noble-gas liquids in detectors dedicated to neutrino physics and dark matter research