An investigation of fish consumption attitude among nutrition experts in Iran

Nutrition experts have a large audience form the general public, so they can exert high impacts on the fish consumption attitude of the lay people. As such, we deemed an investigation of the fish consumption attitude of nutrition experts of great importance in fish extension planning and policy making. We selected 144 nutrition experts and interviewed them in September 2005. The results showed that 64% of the respondents believed advertisement on fish consumption could have high to very high effect on the promotion of fish consumption attitude of the people

Stability of Topological Black Holes

We explore the classical stability of topological black holes in d-dimensional anti-de Sitter spacetime, where the horizon is an Einstein manifold of negative curvature. According to the gauge invariant formalism of Ishibashi and Kodama, gravitational perturbations are classified as being of scalar, vector, or tensor type, depending on their transformation properties with respect to the horizon manifold. For the massless black hole, we show that the perturbation equations for all modes can be reduced to a simple scalar field equation. This equation is exactly solvable in terms of hypergeometric functions, thus allowing an exact analytic determination of potential gravitational instabilities. We establish a necessary and sufficient condition for stability, in terms of the eigenvalues $\lambda$ of the Lichnerowicz operator on the horizon manifold, namely $\lambda \geq -4(d-2)$. For the case of negative mass black holes, we show that a sufficient condition for stability is given by $\lambda \geq -2(d-3)$.Comment: 20 pages, Latex, v2 refined analysis of boundary conditions in dimensions 4,5,6, additional reference

AC Impedance Analysis of the Al/ZnO/p-Si/Al Schottky Diode: C-V Plots and Extraction of Parameters

In this research, we report on the measurement of the capacitance-voltage (C-V) characteristics Al / ZnO / p-Si / Al Schottky diode at room temperature and in dark condition fabricated by spray pyrolysis process. C-V characteristics, within the range of frequencies 5 kHz-5 MHz, are investigated and microelectronic parameters are extracted. Donor density and diffusion potential vary with frequency from 15 to 28 1014 cm – 3, 0.21 to 0.45 V. Besides, the interface state density of Al /ZnO /pSi/Al Schottky is determined and found to be 1012 (eV cm²) – 1. Calculated at 1 MHz, the interfacial layer thickness and depletion layer width are of 760 Å and 0.28 m

Carrier-induced ferromagnetism in n-type ZnMnAlO and ZnCoAlO thin films at room temperature

The realization of semiconductors that are ferromagnetic above room temperature will potentially lead to a new generation of spintronic devices with revolutionary electrical and optical properties. Transition temperatures in doped ZnO are high but, particularly for Mn doping, the reported moments have been small. We show that by careful control of both oxygen deficiency and aluminium doping the ferromagnetic moments measured at room temperature in n-type ZnMnO and ZnCoO are close to the ideal values of 5mB and 3mB respectively. Furthermore a clear correlation between the magnetisation per transition metal ion and the ratio of the number of carriers to the number of transition metal donors was established as is expected for carrier induced ferromagnetism for both the Mn and Co doped films. The dependence of the magnetisation on carrier density is similar to that predicted for the transition temperature for a dilute magnetic semiconductor in which the exchange between the transition metal ions is through the free carriers.Comment: 14 pages pd