pistachio nuts are the major non-oil export agricultural commodity in iran. the existence of empty shells among the shells with kernels reduces the quality of the nuts and, consequently, their market value. in pistachio processing plants, empty shells are generally separated from shells with kernels by the flotation method. but this method is not precise and may encourage the growth of fungi in...

background: marine pollution is a global environmental problem that its monitoring by ideal biomonitors is of great importance. marine organisms, especially mussels, have the ability to accumulate metals from the environment they can be considered as a biomonitoring agent. methods: in this study, concentrations of heavy metals were measured in saccostrea cucullata collected from seven sites on ...

this research was conducted to evaluate the possibility using peanut shells compost as a suitable medium in cultivating ornamental plants. effect of peanut shells composts on the growth of viola tricolor and marigold was investigated during seven months. peat + perlite (with a ratio of 2:1) used as control treatment and peat replaced by 25, 50, 75 and 100 % v/v of peanut shells compost. plant g...

this study aimed to investigate the effects of stiffeners on buckling of thin cylindrical shells under uniform axial compression. to this end, more than 300 finite element models of stiffened cylindrical shells were prepared. the variables considered are shell thickness, number, dimension and the location of the vertical and horizontal stiffeners as well as circular symmetrical imperfections. r...

the effect of axial deformation of shell particles on the dynamic instability (flutter) of cantilevered cylindrical shells made of functionally graded materials (fgm) under an end axial follower force is addressed. to this end, at first, results for free vibration of fgm cylindrical shells were verified with previous outcomes and they were in very good agreement. then, the effect of axial defor...

this study aims to investigate the effects of geometric imperfections on buckling of thin cylindrical shells due to global shear. to this end, more than 320 finite element models of cylindrical shells with different diameter to thickness ratios were prepared. random imperfections with different amplitudes were applied to numerical models. the results revealed that global buckling of cylindrical...

Most hermit crabs depend on empty gastropod shells for shelter; competition for appropriate shells is often severe. This study determined whether shells that have been drilled by naticid gastropods are suitable for occupancy by the hermit crab Pagurus longicarpus. Differences in the characteristics of empty shells and those occupied by hermit crabs were assessed at two adjacent field sites in N...

This study aims to investigate the effects of geometric imperfections on buckling of thin cylindrical shells due to global shear. To this end, more than 320 finite element models of cylindrical shells with different diameter to thickness ratios were prepared. Random imperfections with different amplitudes were applied to numerical models. The results revealed that global buckling of cylindrical...

Background: Marine pollution is a global environmental problem that its monitoring by ideal biomonitors is of great importance. Marine organisms, especially mussels, have the ability to accumulate metals from the environment they can be considered as a biomonitoring agent. Methods: In this study, concentrations of heavy metals were measured in Saccostrea cucullata collected from seven sites on...

The present study aims at investigating stress and deformation behavior of rotating thick truncated conical shells subjected to variable internal pressure. Material prpperties of the shells are graded along the axial direction by Mori-tanaka scheme, which is achieved by elemental gradation of the properties.Governing equations are derived using principle of stsionary total potential (PSTP) and ...