Lifshitz Scaling Effects on Holographic Superconductors

Via numerical and analytical methods, the effects of the Lifshitz dynamical exponent $z$ on holographic superconductors are studied in some detail, including $s$ wave and $p$ wave models. Working in the probe limit, we find that the behaviors of holographic models indeed depend on concrete value of $z$. We obtain the condensation and conductivity in both Lifshitz black hole and soliton backgrounds with general $z$. For both $s$ wave and $p$ wave models in the black hole backgrounds, as $z$ increases, the phase transition becomes more difficult and the growth of conductivity is suppressed. For the Lifshitz soliton backgrounds, when $z$ increases ($z=1,~2,~3$), the critical chemical potential decreases in the $s$ wave cases but increases in the $p$ wave cases. For $p$ wave models in both Lifshitz black hole and soliton backgrounds, the anisotropy between the AC conductivity in different spatial directions is suppressed when $z$ increases. The analytical results uphold the numerical results.Comment: Typos corrected; Footnote added; References added; To be published in Nuclear Physics

Tetra­aqua­bis(3-carboxyl­atopyridine N-oxide-κO 3)cadmium(II)

In the title complex, [Cd(C6H4NO3)2(H2O)4], the CdII atom is situated on a crystallographic centre of inversion. The CdII atom shows a slightly distorted octa­hedral geometry and is coordinated by four O atoms from water mol­ecules and two O atoms from deprotonated carboxyl groups of nicotinic acid N-oxide ligands. The mononuclear complex mol­ecules are linked by O—H⋯O hydrogen bonds, forming a three-dimensional network structure

Tetra-μ-acetato-bis­[(pyridine N-oxide)copper(II)](Cu—Cu)

The mol­ecule of the title binuclear copper(II) complex, [Cu2(CH3COO)4(C5H5NO)2], occupies a special position on a crystallographic inversion centre; the coordination environment of the CuII atom is slightly distorted square-pyramidal and is made up of four O atoms belonging to four acetate groups in the basal plane with the O atom of pyridine N-oxide ligand in the apical position. The Cu—Cu distance is 2.6376 (6) Å

Two types of generalized integrable decompositions and new solitary-wave solutions for the modified Kadomtsev-Petviashvili equation with symbolic computation

The modified Kadomtsev-Petviashvili (mKP) equation is shown in this paper to be decomposable into the first two soliton equations of the 2N-coupled Chen-Lee-Liu and Kaup-Newell hierarchies by respectively nonlinearizing two sets of symmetry Lax pairs. In these two cases, the decomposed (1+1)-dimensional nonlinear systems both have a couple of different Lax representations, which means that there are two linear systems associated with the mKP equation under the same constraint between the potential and eigenfunctions. For each Lax representation of the decomposed (1+1)-dimensional nonlinear systems, the corresponding Darboux transformation is further constructed such that a series of explicit solutions of the mKP equation can be recursively generated with the assistance of symbolic computation. In illustration, four new families of solitary-wave solutions are presented and the relevant stability is analyzed.Comment: 23 page

catena-Poly[silver(I)-μ-pyrazolato-κ2 N:N′]

The title compound, [Ag(C3H3N2)]n, has an infinite helical chain structure in which each pyrazolate group bridges two AgI atoms related by a 21 axis with an intra­chain Ag⋯Ag separation of 3.3718 (7) Å. Each AgI center is linearly coordinated by two N atoms [N—Ag—N angle = 169.98 (14)°]. The chains are held together by inter­chain Ag⋯Ag inter­actions [3.2547 (6) Å], forming a two-dimensional layer. The X-ray single-crystal diffraction result is consonant with that of the ab initio X-ray powder diffraction reported by Masciocchi, Moret, Cairati, Sironi, Ardizzoia & La Monica [J. Am. Chem. Soc. (1994). 116, 7668–7676], with only minor deviations of structural parameters

Penta­aqua­(1H-benzimidazole-5,6-di­carboxyl­ato-κN 3)copper(II) penta­hydrate

The title compound, [Cu(C9H4N2O4)(H2O)5]·5H2O, contains one crystallographically independent CuII atom and one 1H-benzimidazole-5,6-dicarboxyl­ate (bdc) ligand, along with five coordinated and five uncoordinated water mol­ecules. The CuII atom is six-coordinated by one N atom from the bdc ligand and five O atoms from water mol­ecules, giving an octa­hedral coordination geometry. Hydrogen bonds link the mononuclear complex and uncoordinated water mol­ecules into a three-dimensional network

Ba-enhanced dwarf and subgiant stars in the LAMOST Galactic surveys

Ba-enhanced stars are interesting probes of stellar astrophysics and Galactic formation history. In this work, we investigate the chemistry and kinematics for a large sample of Ba-enhanced ([Ba/Fe]$>$1.0) dwarf and subgiant stars with $5000 < T_{\rm eff }< 6700$\,K from LAMOST. We find that both stellar internal evolution process and external mass exchange due to binary evolution are responsible for the origins of the Ba-enhancement of our sample stars. About one third of them exhibit C and N enhancement and ultraviolet brightness excess, indicating they are products of binary evolution. The remaining Ba-enhanced stars with normal C and N abundances are mostly warm stars with $T_{\rm eff} > 6000$\,K. They are likely consequences of stellar internal elemental transport processes, but they show very different elemental patterns to the hotter Am/Fm stars. Our results reveal a substantially lack of high-[$\alpha$/Fe] Ba-enhanced stars in the [Fe/H]--[$\alpha$/Fe] plane, which we dub as a {\em high-$\alpha$ desert}. We suggest it is due to a lower efficiency for producing Ba-enhanced stars by low-mass AGB progenitors in binary systems. Our results call for detailed modellings for these Ba-enhanced stellar peculiars, in the context of both stellar internal elemental transport and external mass accretion.Comment: 20 pages, 17 figures. Accepted for publication in Ap