Electrical conductivity measurement of fayalite under shock compression up to 56 GPa

The electrical conductivity measurements of single‐crystal fayalite are performed under shock wave compression in the pressure range 19.5–56 GPa. The electrical conductivity under shock compression increases by a factor of more than 10^(10) from 0 to 40 GPa. Over the range 19.5–42 GPa the specific conductivity σ can be closely described by log_(10)σ (S/m) = −4.65 + 0.15P (GPa). The conductivity versus pressure relation at room temperature is calculated by using measured values of the activation energy to correct the high‐temperature shock data to room temperature. After the effect of temperature is removed, the increase in conductivity with pressure approximately agrees with that measured under static pressure using a diamond anvil cell by Mao and Bell. Above pressures of ∼42 GPa the conductivity remains at a relatively high level of ∼100 S/m from 40 to 55 GPa

Interdiffusion in InSb/Zn/InSb system

K

Interdiffusion in InSb/Zn/InSb system

K

Onion-like carbon-encapsulated Co, Ni, and Fe magnetic nanoparticles with low cytotoxicity synthesized by a pulsed plasma in a liquid

We synthesized onion-like carbon-encapsulated Co, Ni, and Fe (Co-C, Ni-C, and Fe-C) magnetic nanoparticles with low cytotoxicity using pulsed plasma in a liquid. The pulsed plasma is induced by a low-voltage spark discharge submerged in a dielectric liquid. The face-centered cubic Co and Ni, and body-centered cubic Fe core nanoparticles showed good crystalline structures with an average size between 20 and 30 nm were encapsulated in onion-like carbon coatings with a thickness of 2-10 nm. Vibrating-sample magnetometer measurements revealed the ferromagnetic properties of as-synthesized samples at room temperature (Co-C=360 Oe, Fe-C=380 Oe, and Ni-C=211 Oe). Raman-spectroscopy analysis found onion-like carbon shells composed of well-organized graphitic structures. Thermal gravimetric analysis showed a high ___________________*Corresponding author. Tel/Fax: +08052593295. E-mail address: [email protected] (T. Mashimo)stability of the as-synthesized samples under thermal treatment and oxidation. Cytotoxicity measurements showed higher cancer cell viability than samples synthesized by different methods

Mass-dependent isotopic fractionation of a solid tin under a strong gravitational field

Pure tin metals were centrifuged at 1$\times$106g and at 220 °C for 100 hours, at 0.40$\times$106g at 220–230 °C for 24 hours, and at 0.25$\times$106g at 220 °C for 24 hours. Their isotopic compositions were measured by a secondary ion mass spectrometer (SIMS). 116Sn/120Sn and 124Sn/120Sn ratios of the 1.02$\times$106g sample were considerably different than the initial compositions, and the magnitude of isotopic fractionation reached 2.6±0.1%. A three-isotope diagram of 116Sn/120Sn vs. 124Sn/120Sn shows conclusively that isotopic fractionation caused by a gravitational field depended only on the isotopic mass