The cheif aim of the present investigation is to develop Leslie Gower type three species food chain model with prey refuge. The intra-specific competition among the predators is considered in the proposed model. Besides the logistic growth rate for the prey species, Sokol Howell functional response for predation is chosen for our model formulation. The behaviour of the model system thoroughly analyses near the biologically significant equilibria. The linear stability analysis of the equilibria is carried out in order to examine the response of the system. The present model system experiences Hopf bifurcation depending on the choice of suitable model parameters. Extensive numerical simulation reveals the validity of the proposed model.

Одной из активно развивающихся отраслей лексикологии является неология, объект её изучения - новое слово или неологизм. В задачу неологии входит выявление новых слов и новых значений у уже существующих в языке слов, анализ причин и способов их появления, описание факторов, влияющих на появление нового в лексической системе языка, разработка языковой политики в отношении новых номинаций.  Лексикограф

Different coating layers of fluorescent agent (FCA) on the solar cells were used. An increase of 35% in the energy conversion efficiency of the solar cell have been obtained. This increase is attributed to the reduction ofthe reflected light, eflection spectra show low values at higher thickness which explained the increase ofthe conversion efficiency with increases of layer thickness.

The inhibitive action of Reactive Red (RR31) dye against corrosion of carbon steel in 1M acetic acid solution has been studied using gravimetric method at temperature ranged (288-318)K. The antibacterial activity for the different concentrations of RR31 dye against different bacterial species was studied. The experimental data indicates that this dye acts as a potential inhibitor for carbon-steel in acetic acid medium and the protection efficiency increase with increasing (RR31) dye. The adsorption of (RR31) dye on the carbon steel surface was found to follow Langmuir adsorption isotherm. Thermodynamic data for the adsorption process such as Gibbs free energy change ∆Gads, enthalpy change ∆Hads, and entropy change ∆Sads were estima

In the present work, the thermo-fluid characteristics of a heat exchanger formed of helical coiled tubes immersed in cold water are investigated experimentally. Two types of helical coiled tube are tested, a conventional vertical single helical coiled tube and a new triple vertical helical coiled tube in parallel connection called as meshed coils. The effect of hot water flow rates inside the tubes (ranges from 2.67 to 7.08 l/min), and its inlet temperatures (namely 50, 60, 70 and 80 °C) are investigated. The experimental results show that increasing the flow rate inside the meshed coils leads to decrease the temperature difference between inlet and outlet. An enhancement of heat transfer for meshed coils compared to single coil has been n

Abstract

      This work involves the manufacturing of MAX phase materials include V₂AlC and Cr₂AlC using powder metallurgy as a new class of materials which characterized by regular crystals in lattice. Corrosion behavior of these materials was investigated by Potentiostat to estimate corrosion resistance and compared with the most resistant material represented by SS 316L. The experiments were carried out in 0.01N of NaOH solution at four temperatures in the range of 30–60^oC. Polarization resistance values which calculated by Stern-Geary equation indicated that the MAX phase materials more resistant than SS 316L. Also cyclic polarization tests confirme