The Flatness of Mass-to-Light Ratio on Large Scales

It has been suggested that the mass-to-light ($M/L$) ratio of gravitationally clustering objects is scale-independent on scales beyond galaxy clusters, and may also be independent of the mass of the objects. In this paper, we show that the scale behavior of $M/L$ ratio is closely related to the scaling of cosmic structures larger than clusters. The scale dependence of the $M/L$ ratio can be determined by comparing the observed scaling of richness function (RF) of multi-scale identified objects with the model-predicted scaling of mass function (MF) of large scale structures. Using the multi-scale identified clusters from IRAS 1.2 Jy galaxy survey, we have made comparisons of the observed RF scaling of IRAS $r_{cl}$-clusters with the MF scalings given by simulations of three popular models SCDM, LCDM and OCDM. We find that, the M/L ratio basically is scale-independent from the Abell radius up to about 24 $h^{-1}$Mpc, while it seems to show a slight, but systematical, increase over this scale range. This result is weakly dependent on the cosmological parameters.Comment: AAS Latex file, 8 pages+ 4 figures, accepted for publication in ApJ

Poly[μ2-aqua-[μ2-1,1′-(butane-1,4-di­yl)diimidazole]bis­(μ4-naphthalene-1,4-dicarboxyl­ato)dimanganese(II)]

In the title compound, [Mn2(C12H6O4)2(C10H14N4)(H2O)]n or [Mn2(1,4-ndc)2(L)(H2O)]n, where 1,4-ndc is naphthalene-1,4-dicarboxyl­ate and L is 1,1′-(butane-1,4-di­yl)diimidazole, the coordination polyhedron around each MnII atom is distorted octa­hedral. The water mol­ecule and the L ligand are situated across a twofold rotation axis. The MnII atoms are bridged by 1,4-ndc and L ligands, forming a three-dimensional network. O—H⋯O hydrogen bonds are observed within the network

Poly[μ-aqua-[μ-1,1′-(butane-1,4-di­yl)diimidazole]bis­(μ4-naphthalene-1,4-dicarboxyl­ato)dicadmium(II)]

In the title compound, [Cd2(C12H6O4)2(C10H14N4)(H2O)]n, the coordination polyhedron around each CdII ion is a distorted CdNO5 octa­hedron. The water O atom has site symmetry 2 and the complete 1,1′-(butane-1,4-di­yl)diimidazole (L) ligand is generated by inversion. The naphthalene-1,4-dicarboxyl­ate and L ligands bridge the metal centres, forming a three-dimensional framework, which is consolidated by O—H⋯O hydrogen bonds

Poly[tris­(μ-benzene-1,4-dicarboxylato)bis­(dipyrido[3,2-a:2′,3′-c]phenazine)trimanganese(II)]

In the title compound, [Mn3(C8H4O4)3(C14H8N4)2]n, one Mn atom is located on an inversion centre and is six-coordinated by four carboxyl­ate O atoms from different benzene-1,4-dicarboxyl­ate (1,4-bdc) ligands and two phenanthrene N atoms from a dipyrido[3,2-a:2′,3′-c]phenazine ligand. The other Mn atom is also six-coordinate, binding to six carboxyl­ate O atoms from different 1,4-bdc ligands. The dicarboxyl­ate groups chelate and bridge the two Mn atoms and a symmetry-related Mn atom to form a trimanganese unit. Bridging of the trinuclear MnII clusters leads to a two-dimensional structure

Dynamics Model of Carrier-based Aircraft Landing Gears Landed on Dynamic Deck

AbstractIn order to study the carrier-based aircraft landing laws landed on the carrier, the dynamics model of carrier-based aircraft landing gears landed on dynamic deck is built. In this model, the interactions of the carrier-based aircraft landing attitude and the damping force acting on landing gears are considered, and the influence of dynamic deck is introduced into the model through the deck normal vectors. The wheel-deck coordinate system is put forward to solve the complex simulation problem of force-on-wheel which comes from the dynamic deck. At last, by simulation, it is demonstrated that the model can be applied to landing attitude when the carrier-based aircraft is landing on the dynamic deck, it is also proved that the model is comprehensive and suitable for any abnormal landing situation

Effect of magnetic field on the spin resonance in FeTe(0.5)Se(0.5) as seen via inelastic neutron scattering

Inelastic neutron scattering and susceptibility measurements have been performed on the optimally-doped Fe-based superconductor FeTe(0.5)Se(0.5), which has a critical temperature, Tc of 14 K. The magnetic scattering at the stripe antiferromagnetic wave-vector Q = (0.5,0.5) exhibits a "resonance" at ~ 6 meV, where the scattering intensity increases abruptly when cooled below Tc. In a 7-T magnetic field parallel to the a-b plane, Tc is slightly reduced to ~ 12 K, based on susceptibility measurements. The resonance in the neutron scattering measurements is also affected by the field. The resonance intensity under field cooling starts to rise at a lower temperature ~ 12 K, and the low temperature intensity is also reduced from the zero-field value. Our results provide clear evidence for the intimate relationship between superconductivity and the resonance measured in magnetic excitations of Fe-based superconductors.Comment: 4 pages, 3 figure