sulfonated poly (ether ether ketone) (speek) with a low degree of sulfonation (ds = 40%) was prepared for proton exchange membrane fuel cells (pemfc). poly (ether ether ketone) (peek) was sulfonated in concentrated h2so4 under n2 atmosphere and characterized by the hydrogen nuclear magnetic resonance (h-nmr) technique. after preparation of the speek polymer, the obtained polymer was dissolved i...

The present study was carried out to estimate genetic variability parameters for some traits such as pods per plant, cell membrane stability, one thousand kernel weight, flowering period, grain filling period, chlorophyll content, relative water content, leaf excised water content, seed per pod and pod length, in 16 winter rapeseed genotypes. Statistical analysis showed significant differences ...

this study was carried out to evaluate the changes in some important cell parameters under water limitation in sorghum genotypes. a factorial experiment was conducted based on randomized completely design in greenhouse, in university of mohaghegh ardabili in 2014. treatments were water stress at levels of 85, 65, 45 and 25 percent field capacity in and three genotypes of forage sorghum (kfs2, k...

Background: Since cellular membranes play key role in the physiological pathways of the cell, such as fertilization through almost every cellular function to cell division, it is very important to assess the structural and functional activity of the sperm membrane. In this study, a new method for measurement of sperm membrane stability measured the amount of zinc which liberated after being exp...

in order to investigate the effects of drought stress and nitrogen fertilizer on photosynthesis rate and some physiological characteristics in two barley cultivars, a pot experiment was conducted using a randomized complete block design as a factorial experiment with three factors including water stress, nitrogen fertilizer and barley cultivars in three replications. irrigation treatments condu...

this experiment was conducted to study the effect of plastic mulch on the growth and some physiological characteristics of two strawberry cultivars (paros and queen elisa) under drought stress. a factorial experiment was performed based on randomized complete block design with four treatments, including mulch, without mulch, normal irrigation (control) and deficit irrigation (-10 bar) with thre...

this study was conducted to evaluate the effect of drought stress on 22 durum wheat genotypes. different characteristics such as grain weight per spike, plant biomass, 100 grain weight, free proline content in leaves, and percentage of cell membrane damage were studied in greenhouse and laboratory conditions. genotypes were sown under normal irrigation and moisture stress conditions. in stress ...

cold is one of the most important abiotic stresses in some regions of iran. to investigate of some tolerance related traits to cold condition, 22 bread wheat genotypes planted in ardabil region in 1980. after plants passed winter cold condition (135 freezing days), cell membrane stability, chlorophyll content of leaf and crown depth and grain yield of genotypes were measured. anova analysis sho...