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Noda, Yohei; Kumada, Takayuki; Yamaguchi, Daisuke; Shamoto, Shinichi
no journal, ,
We investigated the dynamic nuclear polarization (DNP) performance of two-component type epoxy resin (Araldite(R) Standard and Araldite(R) Rapid) doped with TEMPO radical. The obtained TEMPO-doped epoxy resin sample was polarized up to 39% at 1.2 K and 3.35 Tesla. The achieved DNP performance was close to other conventionally used polymers.
Noda, Yohei; Yamaguchi, Daisuke; Shamoto, Shinichi; Hashimoto, Takeji; Kumada, Takayuki; Takata, Shinichi; Koizumi, Satoshi; Oishi, Kazuki*; Suzuki, Junichi*; Masui, Tomomi*; et al.
no journal, ,
We have developed proton spin polarization technique for contrast variation in small angle neutron scattering (SANS), which utilizes that neutron scattering section can be controlled by polarizing proton spins. Consequently, we succeeded in the analysis of nano-structure in multi-component samples. We will report the detail of our recent activity for getting higher proton spin oplarization. The recent results of SANS measurement with proton spin polarization conducted for the first time at TAIKAN in J-PARC will also be reported.
Kumada, Takayuki; Noda, Yohei*; Ishikawa, Norito
no journal, ,
We compared dynamic nuclear polarization (DNP) behavior of electron-beam irradiated and TEMPO-doped samples. Both of the growth and decay rates of the nuclear polarization of the irradiated samples linearly increased with the irradiation dose, whereas those of the doped sample were quadratically proportional to the TEMPO concentration. This result suggests that the irradiated samples are polarized due to pair of free radicals produced in a spur, whereas the doped sample is polarized by unspecified TEMPO radical pairs accidentally located nearby. We suggest that higher polarization is expected by optimizing irradiation temperature, on which the radical-radical distance in the pair depends.
Kumada, Takayuki; Akutsu, Kazuhiro*; Oishi, Kazuki*; Morikawa, Toshiaki*; Kawamura, Yukihiko*; Suzuki, Junichi*; Torikai, Naoya*
no journal, ,
Scattering power of neutrons against protons depends remarkably on relative directions of their spins. So, polarized neutron scattering profiles vary as a function of proton polarization of measuring specimen. We can extract fruitful structural information from these profiles. This technique named "spin-contrast variation" has been used to study meso-scale bulk structure using small-angle neutron scattering. Now, we plan to apply the spin-contrast variation technique to study surface structure using neutron reflectivity measurements. The spin-contrast neutron reflectivity measurement will determine surface structure of complex soft materials such as adhesives.