16 research outputs found
A unified origin for the 3D magnetism and superconductivity in NaCoO
We analyze the origin of the three dimensional (3D) magnetism observed in
nonhydrated Na-rich NaCoO within an itinerant spin picture using a 3D
Hubbard model. The origin is identified as the 3D nesting between the inner and
outer portions of the Fermi surface, which arise due to the local minimum
structure of the band at the -A line. The calculated spin wave
dispersion strikingly resembles the neutron scattering result. We argue that
this 3D magnetism and the spin fluctuations responsible for superconductivity
in the hydrated systems share essentially the same origin.Comment: 5pages, 6figure
Pilot Analysis of Asbestos-induced Diffuse Pleural Thickening with Respiratory Compromise
We investigated the clinical features of asbestos-induced diffuse pleural thickening (DPT) with severe respiratory compromise. We conducted a retrospective study of consecutive subjects with asbestos-induced DPT. Medical data such as initial symptoms, radiological findings, respiratory function test results, and clinical course were collected and analyzed. There were 24 patients between 2003 and 2012. All were men, and the median age at the development of DPT was 74 years. The top occupational category associated with asbestos exposure was dockyard workers. The median duration of asbestos exposure was 35.0 years, and the median latency from first exposure to the onset of DPT was 49.0 years. There were no significant differences in respiratory function test results between the higher and lower Brinkman index groups or between unilateral and bilateral DPT. Thirteen patients had a history of benign asbestos pleural effusion (BAPE), and the median duration from pleural fluid accumulation to DPT with severe respiratory compromise was 28.4 months. DPT with severe respiratory compromise can develop after a long latency following occupational asbestos exposure and a history of BAPE
Crystallization Behavior of Poly(ε-caprolactone) Chains Confined in Nanocylinders: Effects of Block Chains Tethered to Nanocylinder Interfaces
The crystallization behavior of poly(ε-caprolactone)
(PCL)
chains (i.e., PCL block + PCL homopolymer systems) spatially confined
in nanocylinders with different diameters <i>D</i> has been
investigated as a function of the mole fraction of PCL homopolymers <i>f</i><sub>homo</sub> existing in the PCL chains. The nanocylinders
with PCL chains inside were prepared using the microphase separation
of PCL-<i>block</i>-polystyrene (PCL-<i>b</i>-PS)
diblock copolymers with a photocleavable <i>o</i>-nitrobenzyl
group (ONB) between PCL and PS blocks, and subsequently ONB was cleaved
by a controlled irradiation of UV light to get the PCL chains with
various <i>f</i><sub>homo</sub>. In the isothermal crystallization
process, the crystallinity of PCL chains showed an exponential time
evolution (or first-order kinetics) for all the systems investigated.
The half-time of crystallization of PCL chains with 0 < <i>f</i><sub>homo</sub> < 1 was found to be intermediate between
those of PCL blocks (<i>f</i><sub>homo</sub> = 0) and PCL
homopolymers (<i>f</i><sub>homo</sub> ∼ 1); it decreased
moderately with increasing <i>f</i><sub>homo</sub> in a
smaller nanocylinder (<i>D</i> ∼ 14.9 nm) but increased
slightly in a larger nanocylinder (<i>D</i> ∼ 17.2
nm). We discussed the effects of tethered PCL blocks on the crystallization
mechanism of PCL chains confined in nanocylinders on the basis of
a general theory for polymer nucleation