36,635 research outputs found
Superconductivity and Phase Diagram in (LiFe)OHFeSeS
A series of (LiFe)OHFeSeS (0 x 1)
samples were successfully synthesized via hydrothermal reaction method and the
phase diagram is established. Magnetic susceptibility suggests that an
antiferromagnetism arising from (LiFe)OH layers coexists with
superconductivity, and the antiferromagnetic transition temperature nearly
remains constant for various S doping levels. In addition, the lattice
parameters of the both a and c axes decrease and the superconducting transition
temperature T is gradually suppressed with the substitution of S for Se,
and eventually superconductivity vanishes at = 0.90. The decrease of T
could be attributed to the effect of chemical pressure induced by the smaller
ionic size of S relative to that of Se, being consistent with the effect of
hydrostatic pressure on (LiFe)OHFeSe. But the detailed
investigation on the relationships between and the crystallographic
facts suggests a very different dependence of on anion height from
the Fe2 layer or -Fe2- angle from those in FeAs-based superconductors.Comment: 6 pages, 6 figure
Transmutation prospect of long-lived nuclear waste induced by high-charge electron beam from laser plasma accelerator
Photo-transmutation of long-lived nuclear waste induced by high-charge
relativistic electron beam (e-beam) from laser plasma accelerator is
demonstrated. Collimated relativistic e-beam with a high charge of
approximately 100 nC is produced from high-intensity laser interaction with
near-critical-density (NCD) plasma. Such e-beam impinges on a high-Z convertor
and then radiates energetic bremsstrahlung photons with flux approaching
10^{11} per laser shot. Taking long-lived radionuclide ^{126}Sn as an example,
the resulting transmutation reaction yield is the order of 10^{9} per laser
shot, which is two orders of magnitude higher than obtained from previous
studies. It is found that at lower densities, tightly focused laser irradiating
relatively longer NCD plasmas can effectively enhance the transmutation
efficiency. Furthermore, the photo-transmutation is generalized by considering
mixed-nuclide waste samples, which suggests that the laser-accelerated
high-charge e-beam could be an efficient tool to transmute long-lived nuclear
waste.Comment: 13 pages, 8 figures, it has been submitted to Physics of Plasm
On the implementation of accessible transport system in urban villages: a case study of Shenzhen Futian district
Urban village is a type of living space in rapid urbanized area within P. R. China, the main spatial features of which are highly the assembling buildings and the principal dwelling space for transient population and poor foreigners. Considering the fact that these urban villages may stay for long time, the implementation of accessible transportation may help reduce social exclusion issues. The major difficulties to implement the Accessible Transport System (ATS) there lie in the exceedingly compacted internal and external spaces.
By analyzing the “barrier” and “favorable” aspects of urban villages to the ATS, this study proposes a 'full realization approach' and a 'partial realization approach' in the external and internal spaces of the urban villages. Through in-depth case study of Futian district in Shenzhen, the effectiveness of these approaches will be verified, and the key technical aspects of following research proposals be put forward.postprintThe 12th International Conference on Mobility and Transport for Elderly and Disabled Persons (TRANSED 2010), Hong Kong, China, 2-4 June 2010
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