in this paper the minimum temperatures of 54 weather stations collected for a 31-year period were analyzed for zoning the frost regions in iran. the results of this study show that the average of the number of frost days per year was 62, and the average temperature was 3 degrees of centigrade below zero. dey the tenth month in the iranian calendar, december 22-january 20 with an average of 28, ...

in this paper, a new analytical method is proposed to study the effect of crack and axial load on vibration behavior and stability of the cracked columns. using the local flexibility model, the crack has been simulated by a torsional spring with connecting two segments of column in crack location. by solving governing eigenvalue equation, the effect of crack parameters and axial load on the nat...

The aim of the present work was to assess the feasibility of Acconon MC8-2 EP/NF as a bioadhesive material for developing controlled release gastroretentive microsponges of loratadine. Modified emulsion-solvent diffusion method was employed for the preparation of microsponges (F1-F9) based on  32 factorial design. The amount of ethyl cellulose (EC) and polyvinyl alcohol (PVA) were selected...

A research on the corrosion inhibition of mild steel pitting corrosion in concrete pore solution by sodium nitrite was carried out by employing potentiodynamic, potentiostatic polarization and zero resistance ammetery (ZRA) techniques. Passivity breakdown potential was decreased from the transpassive potential of 700 mV at the absence of chloride to a value of -50 mV when just 0.01M NaCl was ad...

In the present study, analytical solutions are obtained for two-dimensional advection dispersion equation for conservative solute transport in a semi-infinite heterogeneous porous medium with pulse type input point source of uniform nature. The change in dispersion parameter due to heterogeneity is considered as linear multiple of spatially dependent function and seepage velocity whereas seepag...

Let R be a commutative ring with identity and M an R-module. In this paper, we associate a graph to M, sayΓ(RM), such that when M=R, Γ(RM) coincide with the zero-divisor graph of R. Many well-known results by D.F. Anderson and P.S. Livingston have been generalized for Γ(RM). We Will show that Γ(RM) is connected withdiam Γ(RM)≤ 3 and if Γ(RM) contains a cycle, then Γ(RM)≤4. We will also show tha...

The effect of ordinary and restricted selection indices on body weight at different ages changes in birth weight of Iranian Moghani sheep was studied. Traits in the aggregate genotype were birth weight (BW), body weights at 3 (BW3) and 12 months of age (BW12). Two ordinary selection indices (I1 and I2) and two restricted selection indices (R1 and R2) were constructed. BW and BW3 were included i...

In the present study, analytical solutions are obtained for two-dimensional advection dispersion equation for conservative solute transport in a semi-infinite heterogeneous porous medium with pulse type input point source of uniform nature. The change in dispersion parameter due to heterogeneity is considered as linear multiple of spatially dependent function and seepage velocity whereas seepag...