This article has studied the effect of ratio of stiffness and thickness between piezoelectric actuators and host plat has been explored on optimal pattern for placement of piezoelectric work pieces around a hole in thin isotropic plate under static loading to reduce stress concentration. The piezoelectric actuators reduce directly or indirectly the stress concentration by applying positive and ...

in the present study, a field study was performed on some herbaceous plants growing in thesoutheast of ahvaz, where some metal producing industries are active. the aim of this studywas to investigate and compare manganese (mn) and zinc (zn) accumulation in seven dominantherbaceous plants in this area. plant samples were collected randomly. associated soils weresampled from the same sites next t...

background and objectives: one of the most important limiting factors of crop growth in the arid and semi-arid regions, is water deficit stress. mycorrhizal fungi are one of the most important microorganisms in the rhizosphere. the effects of these fungi apply via changes on some of the characteristics of roots and nutrient uptake in host plants in drought conditions. however, symbiotic mycorrh...

using piezoelectric patches the stress concentration around a hole on a plate under tension is reduced and controlled. to attain the reduction in stress two placements for piezoelectric patches is investigated. the first location is top/bottom of the hole with compression induced strain and the second is left/right of the hole with tension induced strains to control the stress flow. the result ...

background: the use of psychology in the workplace and accurate scientific findings in this field, in addition to reducing work-related diseases, can promote the performance of employees. nursing is a stressful job and can be the cause of physical and mental disorders. this study investigates the relationship of personality traits and demographic factors with occupational stress. materials and ...