Karlsruhe Institute of Technology (KIT), Institute for Applied Materials-Applied Materials Physics (IAM-AWP), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
Karlsruhe Institute of Technology (KIT), Institute for Applied Materials-Applied Materials Physics (IAM-AWP), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
Micron. 2019 Dec;127:102754. doi: 10.1016/j.micron.2019.102754. Epub 2019 Sep 20.
Electron energy loss spectroscopy (EELS) was applied to detect and analyze quantitatively helium (He) and tritium (H) enclosed inside bubbles in irradiated beryllium. Both gases were formed in beryllium under neutron irradiation as a consequence of neutron-induced transmutation reactions. They were detected for the first time as pronounced peaks at 13.0 eV for H and 22.4 eV for He in EELS spectra collected from flat hexagonal bubbles. An adhesion of H or formation of thin beryllium hydride layers on the internal basal surfaces was observed. The number densities of both gases were estimated using electron scattering cross-section and intensities obtained from EELS spectra. The number density values estimated for various bubbles fluctuate from 4 to 15 at/nm for He and from 4 to 10 molecules/nm for H. Lower gas number density was measured inside large bubbles. The observed higher density of tritium at inner walls of bubbles seems to confirm very recent ab initio calculations of the interaction of hydrogen isotopes with beryllium surfaces.
电子能量损失谱（EELS）被应用于检测和定量分析辐照铍中气泡内包裹的氦（He）和氚（H）。这两种气体都是在铍中经中子辐照产生的，是中子诱导嬗变反应的结果。它们首次在从平面六方气泡收集的 EELS 光谱中以明显的峰值被检测到，H 的峰值在 13.0 eV，He 的峰值在 22.4 eV。在内部基面观察到 H 的附着或形成薄的氢化铍层。利用电子散射截面和从 EELS 光谱获得的强度来估计两种气体的数密度。各种气泡内气体的数密度估计值在 4 到 15 个/（nm·原子）之间，He 的数密度在 4 到 10 个/（nm·原子）之间，H 的数密度在 4 到 10 个/（nm·原子）之间。在大的气泡内测量到的气体数密度较低。在气泡内壁观察到的氚的高密度似乎证实了最近对氢同位素与铍表面相互作用的从头计算。
