Publications by authors named "Runsheng Yu"

Article Synopsis
  • * A novel positron annihilation lifetime spectrometer is used to analyze liquid scintillator samples without touching the positron source, providing accurate measurements and low background interference.
  • * Results include a measured ortho-positronium lifetime of 3.02 ns, insights on oxygen's interaction with positronium, and calculations related to annihilation rate and free volume, which may improve understanding of gas solubility in liquids.
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Cathodic CO adsorption and activation is essential for high-temperature CO electrolysis in solid oxide electrolysis cells (SOECs). However, the component of oxygen ionic conductor in the cathode displays limited electrocatalytic activity. Herein, stable single Ruthenium (Ru) atoms are anchored on the surface of oxygen ionic conductor (Ce Sm O , SDC) via the strong covalent metal-support interaction, which evidently modifies the electronic structure of SDC surface for favorable oxygen vacancy formation and enhanced CO adsorption and activation, finally evoking the electrocatalytic activity of SDC for high-temperature CO electrolysis.

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In this work, we studied the evolution of vacancy-like defects and the formation of brittle precipitates in a reduced-activation V-Cr-Mn medium-entropy alloy. The evolution of local electronic circumstances around Cr and Mn enrichments, the vacancy defects, and the CrMn precipitates were characterized by using scanning electron microscopy with energy-dispersive spectroscopy, X-ray diffraction, and positron annihilation spectroscopy. The microstructure measurements showed that the Mn and Cr enrichments in the as-cast sample significantly evolved with temperature, i.

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The free volume effects on the dielectric properties of the polymer are ambiguous, and the quantitative effect of free volume on the dielectric properties has rarely been systematically studied, especially in the high-elastic state dipolar (HESD) polymer. In this work, the free volume of dipolar poly(vinylidene fluoride) (PVDF) is regulated by the addition of AlO, which greatly increase the size of free volume holes. Then the effect of free volume on the dielectric properties of PVDF/AlO composites is discussed.

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The microstructural evolution of dilute Al-Ag alloys in its early aging stage and at low temperatures ranging from 15 K to 300 K was studied by the combined use of Positron annihilation lifetime spectroscopy (PALS), high resolution transmission electron microscopy (HRTEM), and positron annihilation Coincidence Doppler broadening (CDB) techniques. It is shown that at low temperatures below 200 K, an Ag-vacancy complex is formed in the quenched alloy, and above 200 K, it decomposes into Ag clusters and monovacancies. Experimental and calculation results indicate that Ag clusters in Al-Ag alloys can act as shallow trapping sites, and the positron trapping rate is considerably enhanced by a decreasing measurement temperature.

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Background: Finding peptides with high binding affinity to Class I major histocompatibility complex (MHC-I) attracts intensive research, and it serves a crucial part of developing a better vaccine for precision medicine. Traditional methods cost highly for designing such peptides. The advancement of computational approaches reduces the cost of new drug discovery dramatically.

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Si-implanted thermal SiO2 layers and their annealing behaviour were investigated. In the results of variable-energy positron annihilation spectroscopy, the defects caused by ion implantation are manifested as a particularly low S parameter in the Si ion implantation region of the SiO2 layer. Compared with Fourier transform infrared measurements, it suggests that the decrease of the line shape S parameter after implantation is related to the compaction of implanted layers induced by the breaking of the SiO2 network structure.

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