mechanical weeding is one of the non-chemical methods to control weeds. in this paper a ‎new mechanism has been presented for mechanical cultivation. the machine works based on ‎the manual tools operation, which farmers still use in small scale for weeding and consists of a ‎number of four-bar linkage mechanisms. each mechanism consists of a blade which moves ‎forward (active course) and backwa...

background : since the use of high concentrations of oxygen in infants may lead to chronic lung problems, using proper methods of care in infants under mechanical ventilation is one of the most important measures in nicu. this study aimed to investigate the effects of prone and supine positions on oxygenation (spo 2 ) in premature infants under mechanical ventilation and comparing infants’ oxyg...

objective(s): the aim of this study was to synthesis new dental nanocomposites reinforced with fabricated glass nanoparticles and compare two methods for fabrication and investigate the effect of this filler on mechanical properties. materials and methods: the glass nanoparticles were produced by wet milling process. the particle size and shape was achieved using psa and sem. glass nanoparticle...

to evaluate genotype × environment interaction (gei) of grapevine, 20 genotypes of grapevines with russian origin were evaluated at one location in urmia and four locations in takestan (two locations under full irrigation and two locations under drought stress). this research was performed in a randomized complete block design with three replications and three vines in each plot, in 2012-2013 s...

recently, bulk nano-structured materials produced by severe plastic deformation (spd) have attracted scientists attention.  materials produced by spd are of great importance because of (1) non-porous structure, (2) great mechanical properties such as high strength and toughness and (3) proper dimension for mechanical and physical testing.  several methods have been introduced for imposing the s...