arXiv subjects

Hiroshi Naramoto

Publications and source records attributed to Hiroshi Naramoto.

3 recordsLinked to original sources

arXiv2023

Transmission ERDA of ubiquitous deuterium in H-containing materials

Transmission-type elastic recoil detection analysis (T-ERDA) using 8.02 MeV He has been successfully applied to determine the concentration of ubiquitous deuterium in mylar and PPS films, both containing hydrogen as a component. The determined D/H ratios of $(1.60\pm 0.08) \times 10^{-4}$ and $(1.23\pm 0.08) \times 10^{-4}$ for mylar and PPS, respectively, are only slightly deviated from the Standard Mean Ocean Water value of $1.55\cdots \times 10^{-4}$. These results indicate potential sensitivity of T-ERDA for analysis of the variation of ubiquitous deuterium in hydrogen-containing materials. Such deuterium analysis might be useful for unique characterization of not only natural, but also synthesized hydrogen-containing materials.

cond-mat.mtrl-sci↗

arXiv2022

Determination of hydrogen concentration in solids by transmission ERDA under nuclear-elastically enhanced recoiling of H by 8 and 9 MeV He

Hydrogen concentrations in thin self-supporting samples of polyphenylene sulfide and muscovite have been determined by nuclear-elastic recoil detection analysis of transmission layout. The analysis procedure is based only on the database of stopping power and recoil cross section for material analysis, without using any reference sample of known H content. For the polyphenylene sulfide sample, the determined value of $(2.87\pm 0.26)\times 10^{22}\,{\rm H}/$cm$^{3}$ is in good agreement with the calculated value of $3.01 \times 10^{22}\,{\rm H}/$cm$^{3}$. For the muscovite sample, the H concentration originating each from bound water and absorbed water is uniform over the entire thickness of the sample. The determined concentration $(9.43 \pm 0.75) \times 10^{21}$ H$/$cm$^{3}$ of the muscovite agrees excellently with the value of $9.36 \times 10^{21}$ H$/$cm$^{3}$ obtained from other quantitative analyses typically applied for minerals. The present results demonstrate the capability of accurate determination of H contents in materials and minerals by transmission ERDA.

cond-mat.mtrl-sci↗

arXiv2013

The high hydrogen adsorption rate material based on graphane decorated with alkali metals

The graphane with chemically bonded alkali metals (Li, Na, K) was considered as potential material for hydrogen storage. The ab initio calculations show that such material can adsorb as many as 4 hydrogen molecules per Li, Na and K metal atoms. These values correspond to 12.20 wt%, 10.33 wt% and 8.56 wt% of hydrogen, respectively and exceed the DOE requirements. The thermodynamic analysis shows that Li-graphane complex is the most promising for hydrogen storage with ability to adsorb 3 hydrogen molecules per metal atom at 300 K and pressure in the range from 5 to 250 atm.

cond-mat.mes-hall↗