background: in this study, the inhibition rate of different oil concentrations containing pcbs (1242 and 1254 pcb arochlors) on the anaerobic biomass was investigated by specific methanogenic activity using the vials with volume of 120 ml. methods: original samples were divided into two groups: with soil containing pcbs and without pcbs and the control samples in both cases were just contained ...

background : in this study, the inhibitory effect of ethylene dichloride (edc) on biodegradation was investigated using the specific methanogenic activity (sma) test of anaerobic biomass. methods: in the present study, 40 sma tests were performed using 120-ml vials in batch mode. substrate, biomass, and biogas occupied 66%, 17%, and 17% (v/v) of the volume of each vial, respectively. the durati...

background: the antibiotics are excreted after their effect on the host body and together with other waste disposal are entered the treatment plant processes. antibiotics prevent the biological sewage treatment in the plant which consequently causes hazards to the environmental and human health. the purpose of this study was to investigate the effect of some popular antibiotics used by human an...

this study investigated the effect, on reactor performance and biomass retention inside the bed, of the material used to make the supports of anaerobic fixed-bed reactors. three inert supports of similar shape but made of three different materials polyvinyl chloride, polypropylene, high-density polyethylene were manufactured and used. all three supports had the same specific surface area but di...

Denitrifying enzyme activity (DEA) in artificially established denitrification activity zones was, on average, 3.5-fold greater than in bulk soil. Denitrifier biomass was between 1 and 4 orders of magnitude greater in activity zones. Denitrifier specific activity was lower in activity zones and more similar to specific activity values reported for pure cultures of denitrifying bacteria added to...

zinc has previously been reported to alleviate salinity stress in plants. in this study, we monitored various biomass and chlorophyll fluorescence parameters to determine the optimum zinc sulfate concentration that can be used as foliar spray to alleviate salinity stress in glycine soja. the plants subjected to a series of salinity levels (nacl concentration of 0, 100, 200, and 300 mmol l-1), a...

grafting of cucurbitaceae species to some rootstocks seems to be especially beneficial for the nitrogen nutrition of these plants. moreover, melons (cucumis melo l.) have been considered among those plants that could benefit from the addition of silicon (si) in the nutrient solution (ns). thus, two experiments were carried out in the following order: (i) it was investigated how grafting affects...