Developing and utilizing an Euler computational method for predicting the airframe/propulsion effects for an aft-mounted turboprop transport. Volume 2: User guide

This manual explains how to use an Euler based computational method for predicting the airframe/propulsion integration effects for an aft-mounted turboprop transport. The propeller power effects are simulated by the actuator disk concept. This method consists of global flow field analysis and the embedded flow solution for predicting the detailed flow characteristics in the local vicinity of an aft-mounted propfan engine. The computational procedure includes the use of several computer programs performing four main functions: grid generation, Euler solution, grid embedding, and streamline tracing. This user's guide provides information for these programs, including input data preparations with sample input decks, output descriptions, and sample Unix scripts for program execution in the UNICOS environment

Universal scaling functions for bond percolation on planar random and square lattices with multiple percolating clusters

Percolation models with multiple percolating clusters have attracted much attention in recent years. Here we use Monte Carlo simulations to study bond percolation on $L_{1}\times L_{2}$ planar random lattices, duals of random lattices, and square lattices with free and periodic boundary conditions, in vertical and horizontal directions, respectively, and with various aspect ratio $L_{1}/L_{2}$. We calculate the probability for the appearance of $n$ percolating clusters, $W_{n},$ the percolating probabilities, $P$, the average fraction of lattice bonds (sites) in the percolating clusters, $_{n}$ ($_{n}$), and the probability distribution function for the fraction $c$ of lattice bonds (sites), in percolating clusters of subgraphs with $n$ percolating clusters, $f_{n}(c^{b})$ ($f_{n}(c^{s})$). Using a small number of nonuniversal metric factors, we find that $W_{n}$, $P$, $_{n}$ ($_{n}$), and $f_{n}(c^{b})$ ($f_{n}(c^{s})$) for random lattices, duals of random lattices, and square lattices have the same universal finite-size scaling functions. We also find that nonuniversal metric factors are independent of boundary conditions and aspect ratios.Comment: 15 pages, 11 figure

Non-generality of the Kadowaki-Woods ratio in correlated oxides

An explicit expression for the Kadowaki-Woods ratio in correlated metals is derived by invoking saturation of the (high-frequency) Fermi-liquid scattering rate at the Mott-Ioffe-Regel limit. Significant deviations observed in a number of oxides are quantitatively explained due to variations in carrier density, dimensionality, unit cell volume and the number of individual sheets in the Brillouin zone. A generic re-scaling of the original Kadowaki-Woods plot is also presented.Comment: 9 pages of text, 1 table, 2 figure

Non-equilibrium Relations for Spin Glasses with Gauge Symmetry

We study the applications of non-equilibrium relations such as the Jarzynski equality and fluctuation theorem to spin glasses with gauge symmetry. It is shown that the exponentiated free-energy difference appearing in the Jarzynski equality reduces to a simple analytic function written explicitly in terms of the initial and final temperatures if the temperature satisfies a certain condition related to gauge symmetry. This result is used to derive a lower bound on the work done during the non-equilibrium process of temperature change. We also prove identities relating equilibrium and non-equilibrium quantities. These identities suggest a method to evaluate equilibrium quantities from non-equilibrium computations, which may be useful to avoid the problem of slow relaxation in spin glasses.Comment: 8 pages, 2 figures, submitted to JPS

The effect of uniaxial pressure on the magnetic anisotropy of the Mn_{12}-Ac single-molecule magnet

We study the effect of uniaxial pressure on the magnetic hysteresis loops of the single-molecule magnet Mn_{12}-Ac. We find that the application of pressure along the easy axis increases the fields at which quantum tunneling of magnetization occurs. The observations are attributed to an increase in the molecule's magnetic anisotropy constant D of 0.142(1)%/kbar. The increase in D produces a small, but measurable increase in the effective energy barrier for magnetization reversal. Density-functional theory calculations also predict an increase in the barrier with applied pressure.Comment: version accepted by EPL; 6 pages, including 7 figures. Small changes and added reference

Superconductivity at 38 K in Iron-Based Compound with Platinum-Arsenide Layers Ca10(Pt4As8)(Fe2-xPtxAs2)5

We report superconductivity in novel iron-based compounds Ca10(PtnAs8)(Fe2-xPtxAs2)5 with n = 3 and 4. Both compounds crystallize in triclinic structures (space group P-1), in which Fe2As2 layers alternate with PtnAs8 spacer layers. Superconductivity with a transition temperature of 38 K is observed in the n = 4 compound with a Pt content of x ~ 0.36 in the Fe2As2 layers. The compound with n = 3 exhibits superconductivity at 13 K.Comment: OPEN SELECT article, 11 pages, 5 figures, 2 table

Prevalence and determinants of anxiety and depression in end stage renal disease (ESRD). A comparison between ESRD patients with and without coexisting diabetes mellitus

Objective: To compare anxiety and/or depressive symptoms between patients with end-stage renal disease with and without comorbid diabetes and identify factors associated with symptoms of distress in this population. Methods: Data from two studies (conducted between 2010 and 2014) were pooled. A total of 526 patients on hemodialysis (68.8% with diabetes) completed the Hospital Anxiety and Depression Scale (HADS). Elevated symptoms were defined as HADS-Anxiety or HADS-Depression ≥ 8. Univariate and multivariate logistic regressions were used to estimate associations between diabetic status, and other socio-demographic and clinical factors with baseline clinical anxiety and depression. Results: A total of 233 (45.4%) reported elevated anxiety symptoms and 256 (49.9%) reported elevated depressive symptoms sufficient for caseness. Rates were not different between patients with and without diabetes. Risk for clinical depression was higher in patients who were single/unpartnered (OR = 1.828), Chinese vs. Malay (OR = 2.05), or had lower albumin levels (OR = 0.932). None of the parameters were associated with anxiety caseness. Conclusion: Sociocultural factors rather than comorbid burden may help identify patients at risk for depression. The high rates of anxiety and depression underlie the importance for monitoring and intervention in dialysis care

Exciton Mediated Superconductivity in PrOs4Sb12

The most important character of the exotic superconductor PrOs4Sb12 is the existence of low-lying excitations (excitons) with a finite energy gap and it appears as the magnetic field-induced order above 4.5 T. We focus on the a_u conduction band, which hybridizes with a Pr 4f^2 state strongly, coupled to the excitons. It results in an attractive interaction between the conduction electrons. The symmetry of the superconducting order parameter is determined by dispersion relation of the exciton. For the bcc system PrOs4Sb12, a d-wave state [kx ky + omega ky kz + omega^2 kz kx, omega=exp(pm i 2 pi/3)] is stabilized with broken time reversal symmetry.Comment: 4 page

Critical exponents and the correlation length in the charge exchange manganite spin glass Eu_{0.5}Ba_{0.5}MnO_{3}

The critical regime of the charge exchange (CE) manganite spin glass Eu_{0.5}Ba_{0.5}MnO_{3} is investigated using linear and non linear magnetic susceptibility and the divergence of the third ordered susceptibility (chi{_3}) signifying the onset of a conventional freezing transition is experimentally demonstrated. The divergence in chi{_3}, dynamical scaling of the linear susceptibility and relevant scaling equations are used to determine the critical exponents associated with this freezing transition, the values of which match well with the 3D Ising universality class. Magnetic field dependence of the spin glass response function is used to estimate the spin correlation length which is seen to be larger than the charge/orbital correlation length reported in this system.Comment: 4 pages, 4 Figure

Weak ferromagnetism and internal magnetoelectric effect in LiFeP2_2O7_7

The magnetic, thermodynamic, and pyroelectric properties of LiFeP$_2$O$_7$ single crystals are investigated with emphasis on the magnetoelectric interaction of the electrical polarization with the magnetic order parameter. The magnetic order below T$_N\simeq$ 27 K is found to be a canted antiferromagnet with a weak ferromagnetic component along the $b-$axis. A sharp peak of the pyroelectric current at T$_N$ proves the strong internal magnetoelectric interaction resulting in a sizable polarization decrease at the onset of magnetic order. The magnetoelectric effect in external magnetic fields combines a linear and a quadratic field dependence below T$_N$. Thermal expansion data show a large uniaxial magnetoelastic response and prove the existence of strong spin lattice coupling. LiFeP$_2$O$_7$ is a polar compound with a strong interaction of the magnetic order parameter with the electric polarization and the lattice.Comment: 8 pages, 9 figures, to be published in Phys. Rev.