We propose an evolutionary scenario by successive bursts of star formation to reproduce the chemical properties of massive nearby Starburst Nucleus Galaxies (SBNGs). The N/O abundance ratios in SBNGs are ∼ 0.2 dex higher than in normal H II regions observed in the disks of late–type spirals. The variation of the N/O ratio as a function of metallicity follows a primary+secondary relation, but th...

In this chapter, the application of computational techniques in environmental exposure assessment was described. The most important groups of these techniques are Multimedia Mass-balance (MM) modelling and Quantitative Structure-Activity/Structure-Property Relationships (QSAR/QSPR) modelling. Multimedia Mass-balance models have been widely utilized for studying Long-Range Transport Potential (L...

in recent years, the application of composite materials in aircraft and space vehicle structural components has become increasingly popular. preventing failure of composite structural systems has been an important issue in engineering design. due to the lack of through-the-thickness reinforcement, structures made from laminated composite materials and adhesively bonded joints are highly suscept...

A statistical mechanical based equation of state has been employed to calculate the liquid density of lead, mercury, bismuth and lead-bismuth and lead-lithium eutectic alloys.The equation is basically that of Song, Mason and Ihm [Ihm G, Song Y, Mason EA. J. Chem. Phys.1991; 94: 3839] which is modified by Ghatee and Boushehri. Three temperature dependent parameters are required to use this e...

Soil physical properties have an important role on vegetation growththrough affecting the development of root system. The aim of this study was toinvestigate the trampling effect of livestock grazing on soil physical properties andvegetation cover changes. The experiment was conducted on three range conditionsites (Reference, Key and Critical area) with ten frequencies in HosseinabadeKudistan i...

The buckling analysis of stiffened cylindrical shells by rings and stringers made of functionally graded materials subjected to axial compression loading is presented. It is assumed that the material properties vary as a power form of the thickness coordinate variable. The fundamental relations, the equilibrium and stability equations are derived using the first order shear deformation theory. ...

a statistical mechanical based equation of state has been employed to calculate the liquid density of lead, mercury, bismuth and lead-bismuth and lead-lithium eutectic alloys.the equation is basically that of song, mason and ihm [ihm g, song y, mason ea. j. chem. phys.1991; 94: 3839] which is modified by ghatee and boushehri. three temperature dependent parameters are required to use this equat...