A theoretical model for determining thermal conductivity of porous solid materials

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.In present study a new-developed simple algebraic equation is used to find out the effective thermal conductivity of new–produced composite materials that have nonhomogenous microscopic porosity. Thermal power plant ashes, tragacanth and portland cement are used as binding components of these porous composite materials. By varying the mixing ratio of three components, 24 samples have been produced. Effective thermal conductivity coefficients obtained by the algebraic method is then compared to the ones obtained by experimental measurement techniques. The theoretical results are found to be agreeable with the experimental results.dc201

Spatially homogeneous Lifshitz black holes in five dimensional higher derivative gravity

We consider spatially homogeneous Lifshitz black hole solutions in five dimensional higher derivative gravity theories, which can be possible near horizon geometries of some systems that are interesting in the framework of gauge/gravity duality. We show the solutions belonging to the nine Bianchi classes in the pure R^2 gravity. We find that these black holes have zero entropy at non-zero temperatures and this property is the same as the case of BTZ black holes in new massive gravity at the critical point. In the most general quadratic curvature gravity theories, we find new solutions in Bianchi Type I and Type IX cases.Comment: 15 pages, no figure; v2, refs added, version to appear in JHE

Lifshitz black holes in Brans-Dicke theory

We present an exact asymptotically Lifshitz black hole solution in Brans-Dicke theory of gravity in arbitrary $n(\ge 3)$ dimensions in presence of a power-law potential. In this solution, the dynamical exponent $z$ is determined in terms of the Brans-Dicke parameter $\omega$ and $n$. Asymptotic Lifshitz condition at infinity requires $z>1$, which corresponds to $-(n-1)/(n-2) \le \omega < -n/(n-1)$. On the other hand, the no-ghost condition for the scalar field in the Einstein frame requires $0<z \le 2(n-2)/(n-3)$. We compute the Hawking temperature of the black hole solution and discuss the problems encountered and the proposals in defining its thermodynamic properties. A generalized solution charged under the Maxwell field is also presented.Comment: 32 pages, no figure. v2: revised version. Section 3.1 and Appendix B improved. The argument in Appendix A clarified. v3: References added. v4: analysis on the black hole thermodynamical properties corrected. Final version to appear in JHE

Use of intramedullary fully-threaded pins in the fixation of feline and canine humeral, femoral and tibial fractures

Intramedullary fully-threaded pins were manufactured from an alloy of titanium, aluminium and vanadium in a fully-threaded style. Pins were produced in various diameters, ranging from 4 mm to 11 mm. Pin lengths varied from 5 cm to 22 cm. The proximal end of the pins was designed to fit into a hexagonal screwdriver, while the distal end was slightly tapered to allow for ease of entry into cancellous bone

Meibomian adenoma in a Syrian hamster (Mesocricetus auratus): a case report

A two-year old male Syrian hamster (Mesocricetus auratus) was brought to the Surgery Clinic at the Istanbul University, Veterinary Faculty, Research and Practice Hospital, with a non-healing wound on the right upper eyelid. An ulcerated, bleeding wound was observed and diagnosed as an eyelid mass. The eyelid mass was excised and submitted for histopathological examination, which resulted in a diagnosis of meibomian adenoma. After excision of the mass, the right upper eyelid became deformed and adopted an abnormal shape. The surgical site was examined two weeks later. No abnormality was observed and the appearance of the right eyelid had returned to normal. Although there are many reports on benign tumours such as polyps, adenomas, haemangiomas and papillomas in hamsters, to the authors' knowledge, this is the first report on a meibomian adenoma in a Syrian hamster which was resolved by surgery