GD 99 - an unusual, rarely observed DAV white dwarf

New observations of GD 99 are analysed. The unusual pulsation behaviour, showing both long and short periods, has been confirmed. All the available periods show a grouping of short and long period modes with roughly regular spacing. If we interpret the groups separately, a binary nature can be a possible explanation as in the similar cases of WD 2350-0054 and G29-38.Comment: 2 pages, 1 eps figure; has been accepted for publication in Communications in Asteroseismology (Vol. 150, 2007), Proceedings of the Vienna Workshop on the Future of Asteroseismolog

Ferrofluid Flow in the Presence of Magnetic Dipole

The aim of this paper is to introduce new results on magneto-thermomechanical interaction between heated viscous incompressible ferrofluid and a cold wall in the presence of a spatially varying magnetic field. Similarity transformation is applied to convert the governing nonlinear boundary layer equations into coupled nonlinear ordinary differential equations. This system is numerically solved using higher derivative method. The effects of governing parameters corresponding to various physical conditions are investigated. Numerical results are represented for distributions of velocity and temperature, for dimensionless wall skin friction and for heat transfer coefficients. Two bifurcate solutions have been obtained and one of the two solutions compares well with previous studies

Experimental Investigation of Viscosity of Glycerol Based Nanofluids Containing Carbon Nanotubes

The addition of solid nanoparticles to liquids provide significant enhancement of heat transfer and hydrodynamic flow. The viscosity of nanofluids is important for nanofluid transport related to flow dynamics and heat transfer. The aim of the paper is to investigate experimentally the viscosity of nanofluids prepared with glycerol base and nitrogen-doped bamboo shaped multi-walled carbon nanotubes (MWCNTs). The samples are prepared with 0.1, 0.2, 0.5 and 1.0 wt.% MWCNTs. The viscosity of glycerol and MWCNTs nanofluid suspensions are measured at various temperatures and rotational speeds (shear rates). The influence of nanotubes amount, temperature and rotational speed on the viscosity is investigated

Coherent states in fermionic Fock-Krein spaces and their amplitudes

We generalize the fermionic coherent states to the case of Fock-Krein spaces, i.e., Fock spaces with an idefinite inner product of Krein type. This allows for their application in topological or functorial quantum field theory and more specifically in general boundary quantum field theory. In this context we derive a universal formula for the amplitude of a coherent state in linear field theory on an arbitrary manifold with boundary.Comment: 20 pages, LaTeX + AMS + svmult (included), contribution to the proceedings of the conference "Coherent States and their Applications: A Contemporary Panorama" (Marseille, 2016); v2: minor corrections and added axioms from arXiv:1208.503

Computing the first eigenpair of the p-Laplacian via inverse iteration of sublinear supersolutions

We introduce an iterative method for computing the first eigenpair $(\lambda_{p},e_{p})$ for the $p$-Laplacian operator with homogeneous Dirichlet data as the limit of $(\mu_{q,}u_{q})$ as $q\rightarrow p^{-}$, where $u_{q}$ is the positive solution of the sublinear Lane-Emden equation $-\Delta_{p}u_{q}=\mu_{q}u_{q}^{q-1}$ with same boundary data. The method is shown to work for any smooth, bounded domain. Solutions to the Lane-Emden problem are obtained through inverse iteration of a super-solution which is derived from the solution to the torsional creep problem. Convergence of $u_{q}$ to $e_{p}$ is in the $C^{1}$-norm and the rate of convergence of $\mu_{q}$ to $\lambda_{p}$ is at least $O(p-q)$. Numerical evidence is presented.Comment: Section 5 was rewritten. Jed Brown was added as autho

Solution Equilibrium Studies on Anticancer Ruthenium(II)–eta6-p-cymene Complexes of 3-Hydroxy-2(1H)-pyridones

Ru-II(eta(6)-p-cymene) complexes of bidentate (0,0) alkoxycarbonylmethyl-3-hydroxy-2(1H)-pyridone ligands exhibit in vitro antitumor activity. We determined the stoichiometry and stability in aqueous solution of two examples by pH-potentiometry, H-1 NMR spectroscopy and UV-vis spectrophotometry and also characterized the proton dissociation processes of the ligands. Formation of mono-ligand complexes with moderate stability was found to predominate in the physiological pH range. Moreover, the chlorido/aqua co-ligand exchange processes of the [Ru-II(eta(6)-p-cymene)(L)(H2O)](+) species were also monitored and 55-65% of the aqua ligand was found to be replaced by chloride in 0.2 M KCl-containing aqueous solutions. Under basic conditions, the complexes decompose to dinuclear tri-hydroxido-bridged [Ru-2(I)(eta(6)-p-cymene)(2)(OH)(3)](+) and metal-free ligand and also a hydroxido species [Ru-II(eta(6)-p-cymene)(L)(OH)] was found. Furthermore, the ligands contain an ester functional group, which may hydrolyze at basic pH, which is however negligible at acidic or neutral pH