Abstract
We obtain constraints on cosmological parameters from the spherically averaged redshift-space correlation function of the CMASS Data Release 9 (DR9) sample of the Baryonic Oscillation ...Spectroscopic Survey (BOSS). We combine this information with additional data from recent cosmic microwave background (CMB), supernova and baryon acoustic oscillation measurements. Our results show no significant evidence of deviations from the standard flat Λ cold dark matter model, whose basic parameters can be specified by Ωm = 0.285 ± 0.009, 100 Ωb = 4.59 ± 0.09, n
s = 0.961 ± 0.009, H
0 = 69.4 ± 0.8 km s−1 Mpc−1 and σ8 = 0.80 ± 0.02. The CMB+CMASS combination sets tight constraints on the curvature of the Universe, with Ω
k
= −0.0043 ± 0.0049, and the tensor-to-scalar amplitude ratio, for which we find r < 0.16 at the 95 per cent confidence level (CL). These data show a clear signature of a deviation from scale invariance also in the presence of tensor modes, with n
s < 1 at the 99.7 per cent CL. We derive constraints on the fraction of massive neutrinos of f
ν < 0.049 (95 per cent CL), implying a limit of ∑m
ν < 0.51 eV. We find no signature of a deviation from a cosmological constant from the combination of all data sets, with a constraint of w
DE = −1.033 ± 0.073 when this parameter is assumed time-independent, and no evidence of a departure from this value when it is allowed to evolve as w
DE(a) = w
0 + w
a
(1 − a). The achieved accuracy on our cosmological constraints is a clear demonstration of the constraining power of current cosmological observations.
A new chromophore has been identified in copper‐doped apatite pigments having the general composition Sr10(PO4)6(CuxOH1−x−y)2, in which x=0.1, 0.3 and y=0.01–0.42. By using X‐ray absorption ...spectroscopy, low‐temperature magnetization measurements, and synchrotron X‐ray powder structure refinement, it has been shown that the oxygenated compounds contain simultaneously diamagnetic Cu1+ and paramagnetic Cu3+ with S=1. Cu3+ is located at the same crystallographic position as Cu1+, being linearly coordinated by two oxygen atoms and forming the OCuO− anion. The Raman spectroscopy study of A10(PO4)6(CuxOH1−x−y)2,, in which A=Ca, Sr, Ba, reveals resonance bands at 651–656 cm−1 assigned to the symmetric stretching vibration (ν1) of OCuO−. The strontium apatite pigment exhibits a strong paramagnetic anisotropy with an unprecedentedly large negative zero‐field splitting parameter (D) of ≈−400 cm−1. The extreme magnetic anisotropy causes slow magnetization relaxation with relaxation times (τ) up to 0.3 s at T=2 K, which relates the compounds to single‐ion magnets. At low temperature, τ is limited by a spin quantum‐tunneling, whereas at high temperature a thermally activated relaxation prevails with Ueff≈48 cm−1. Strong dependence of τ on the paramagnetic center concentration at low temperature suggests that the spin‐spin relaxation dominates in the spin quantum‐tunneling process. The compound is the first example of a d‐metal‐based single‐ion magnet with S=1, the smallest spin at which an energy barrier arises for the spin flipping.
Chromophore and SIM in one pot: The paramagnetic chromophore OCuO− anion has been found in the phosphate apatite pigment covering the magenta/violet/blue color range. Being the first example of a linear coordinated Cu3+ in a crystal lattice, it exhibits unusual properties: it coexists with a Cu1+ species and shows unprecedentedly large magnetic anisotropy for d ions, which induces slow spin relaxation, relating the pigment to single‐ion magnets (SIMs; see figure).
All‐inorganic single‐ion magnets representing paramagnetic ions incorporated in a crystalline diamagnetic matrix are reviewed. Key results and advantages of this approach in comparison with the ...common strategy based on molecular metal–organic complexes are considered, and some unsolved problems and future perspectives are discussed.
Quite different approach: This work reviews single‐ion magnets (SIMs) representing highly anisotropic magnetic ions embedded in inorganic solid‐state matrixes. This strategy significantly differs from more common metal–organic route of novel SIM construction, but allows air‐ and moisture‐stable SIMs with outstanding characteristics to be obtained.
We calculate the real- and redshift-space clustering of massive galaxies at z ~ 0.5 using the first semester of data by the Baryon Oscillation Spectroscopic Survey (BOSS). We study the correlation ...functions of a sample of 44,000 massive galaxies in the redshift range 0.4 < z < 0.7. We present a halo-occupation distribution modeling of the clustering results and discuss the implications for the manner in which massive galaxies at z ~ 0.5 occupy dark matter halos. The majority of our galaxies are central galaxies living in halos of mass 1013 h --1 M , but 10% are satellites living in halos 10 times more massive. These results are broadly in agreement with earlier investigations of massive galaxies at z ~ 0.5. The inferred large-scale bias (b 2) and relatively high number density () imply that BOSS galaxies are excellent tracers of large-scale structure, suggesting BOSS will enable a wide range of investigations on the distance scale, the growth of large-scale structure, massive galaxy evolution, and other topics.
Magnetically hard ferrites attract considerable interest due to their ability to maintain a high coercivity of nanosized particles and therefore show promising applications as nanomagnets ranging ...from magnetic recording to biomedicine. Herein, we report an approach to prepare nonsintered single-domain nanoparticles of chromium-substituted hexaferrite via crystallization of glass in the system SrO-Fe
O
-Cr
O
-B
O
. We have observed a formation of plate-like hexaferrite nanoparticles with diameters changing from 20 to 190 nm depending on the annealing temperature. We demonstrated that chromium substitution led to a significant improvement of the coercivity, which varied from 334 to 732 kA m
for the smallest and the largest particles, respectively. The results provide a new strategy for producing high-coercivity ferrite nanomagnets.
Samples containing copper oxide doped hydroxyapatite with the composition Ca10(PO4)6(CuxOH1-x-δ)2, x = 0.054 – 0.582, in the mixture with CuO/Cu2O were prepared by a solid-state high-temperature ...treatment at varying annealing temperatures and at different partial water vapor and oxygen pressures. The crystal structures of the apatite compounds were refined using powder X-ray diffraction patterns and the content of copper ions x in the apatite was determined. Copper ions enter exclusively into the apatite trigonal channels formally substituting protons of OH-groups and the hexagonal cell parameters grow approximately linearly with x, the channel volume mostly expanding while the remaining volume of the crystal lattice changing only slightly. The equilibrium copper content in the apatite increases drastically, by almost a factor of 10 with the annealing temperature rising from 800° to 1200°C. The reduction of the water partial pressure leads to a further increase of x, while the dependence of x on the oxygen partial pressure exhibits a maximum. The observed relations are consistent with the proposed chemical reactions implying the copper introduction is followed by the release of a considerable quantity of gaseous products – water and oxygen. The analysis of interatomic distances suggests that the maximum content of copper ions in the channel cannot exceed 2/3.
Location of copper ion in the apatite channel and T-x phase diagram of the system ‘hydroxyapatite – copper oxide’. Display omitted
•Copper ions enter into the apatite trigonal channels up to 58% of stoichiometry.•Copper content in hydroxyapatite increases strongly with the annealing temperature.•Copper content grows with the water vapor partial pressure reduction.•Copper content value peaks at an intermediate partial pressure of oxygen.
Single‐ion magnets (SIMs) are magnetic compounds that could retain their magnetization after removing the field but due to noninteracting isolated magnetic ions (as it is illustrated by the figure) ...instead of domains in classical ferromagnets. Usually they are constructed from metal–organic complexes of magnetic d or f ions but here, a Minireview of another approach that is using inorganic solid state compounds as a matrix for individual magnetic ions with SIM properties is presented by M. A. Zykin et al. on page 8834 ff.
A new simple and versatile technique for the phase transfer of nanoparticles from water to water-immiscible organic solvents is presented. The proposed method is based on using charged colloids as ...carriers for the transfer of nanoparticles with opposite surface charge. The method has been successfully applied for the transfer of SrFe 12 O 19 nanoplatelets and CdTe nanoparticles.
The research materials present the results of the use of respiratory sinus arrhythmia–biofeedback (RSA-BFB) therapy aimed at improving the adaptation of students with different initial autonomic ...tone. It has been shown that the effectiveness of biofeedback therapy significantly depends on the specifics of trophotropic and ergotropic processes in students with various types of autonomic regulation. In individuals with a predominance of vagotonic effects on the heart rate, biofeedback training is most effective at the beginning of the school year; in the case of predominance of sympathetic influences, RSA-BFB therapy most effectively optimizes the functional state of the body at the end of the school year; for a persons with eitonic type of autonomic regulation the healing effect has a stabilizing influence regardless of the annual cycle of learning activity.
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