Experimental study of thermal stability of HTS cable under DC overcurrent

Oxidative Redispersion-Derived Single-Site Ru/CeO2 Catalysts with Mobile Ru Complexes Trapped by Surface Hydroxyls Instead of Oxygen Vacancies

“…As shown in Figure S20 and Table S2, the spent H400+O shared similar coordination numbers (4.8 ± 0.3) and bond distances (2.03 ± 0.03 Å) with the fresh catalyst in their first Ru−O shell, and no contributions from the high-order Ru−O shells or Ru−O−Ru multiple scattering paths could be identified. 46 In line with the results of Xu et al 57 in dealing with CO oxidation over single-site Ru/CeO 2 catalysts, no signs of reactioninduced Ru sintering or agglomeration were identified. Interestingly, by comparing the wavelet-transformed EXAFS spectra in Figures 2H and 6C, it is obvious that the spent H400+O lost most of its Ru−OH feature.…”

“…Taking eq 10 and the spectra in Figure 5A−C into consideration, it was suggested that during the oxidation treatments, the disintegration of Ru nanoparticles went in sync with the trapping of detached Ru−O x complexes (e.g., Ru−O or O−Ru−O). Consequently, the Ru−O−Ce structure, a feature frequently observed in Ru/CeO 2 with single-site Ru species, 18,47,57,58,60 emerged and was detected by Raman (comparing the spectra in Figures 4C and 5E). Among the three H 2 -pretreated Ru/CeO 2 samples, H500 possessed the fewest OH (II) groups (Figure 3C).…”

“…Similar structural information could also be obtained from Raman spectroscopy. As shown in Figure 6D, the fresh and spent H400+O exhibited similar Ru−O−Ce-related bands at 710 and 974 cm −1 , respectively (indicator for the atomically dispersed Ru species on CeO 2 18,47,57,58,60 ), while Ru−OH species (with bands at 783 cm −188 ) could only be identified on the fresh catalyst. These results indicated that the Ru species maintained their initial single-site structure after the oxidation reactions, while the hydroxyls bonded to them�which hindered the Ru sites from being fully involved in the catalytic reactions�were destructed.…”

“…To launch "oxidative redispersion" of the supported Ru nanoparticles, the as-received catalyst was calcined in an air flow (200 mL/min) at 300 °C for 1 h�a proven strategy to produce single-site Ru species over CeO 2 . 17,18,57,58 The thusobtained sample (O300) did show a 1.6 times increased Ru dispersion (Table 1), indicating that the disintegration of Ru nanoparticles occurred during the oxidation treatment. 20−22 As illustrated in Table 1, such treatment did not lead to detectable Ru loss.…”

High temperature superconducting cables and their performance against short circuit faults: current development, challenges, solutions, and future trends

“…A brand new study was conducted in [183] to attain the important factors affecting the electrothermal stability of a single layer DC HTS cable with a 920 A critical current. The cable consists of a stainless steel-based former, inner and outer insulations (PPLP), 2G superconducting tapes, and PI films semiconductor layer.…”