The goal of these studies was to determine how sorption by humic acids affected the bioavailability of polynuclear aromatic hydrocarbons (PAHs) to PAH-degrading microbes. Micellar solutions of humic acid were used as sorbents, and phenanthrene was used as a model PAH. Enrichments from PAH-contaminated soils established with nonsorbed phenanthrene yielded a total of 25 different isolates represe...

introduction the occurrence of mycotoxins in foods and feeds is a problem of major concern in all over the world. profitability of poultry production can be greatly affected due to the frequency of feed contamination and the detrimental effects of these toxins on the performance. aflatoxins, a group of closely related and biologically active mycotoxins, are produced by strains of aspergillus fl...

NanoGene assay is a magnetic bead and quantum dot nanoparticles based gene quantification assay. It relies on a set of probe and signaling probe DNAs to capture the target DNA via hybridization. We have demonstrated the inhibition resistance of the NanoGene assay using humic acids laden genomic DNA (gDNA). At 1 μg of humic acid per mL, quantitiative PCR (qPCR) was inhibited to 0% of its quantif...

Natural attapulgite modified using acid activation, heat treatment, and organic modification was investigated as a humic acid adsorbent and an optimal modification method was confirmed. Results suggest that acid activation should be performed first and followed by organic modification. Optimum dosage of modified attapulgite was 0.7 g/L and the humic acid removal rate reached 97%. Optimum modifi...

The performance of the Sha-he wastewater reclamation plant was evaluated in this study. To remove residual nitrogen after Anaerobic-Anoxic-Oxic (A2O) treatment, three multistage Anoxic-Oxic (A/O) were added to investigate the nitrogen removal efficiency and its mechanism. In addition, the constituents and evolution of dissolved organic matter (DOM) during wastewater reclamation was also investi...

The ecological mechanism of survival of Aeromonas salmonicida, the bacterial pathogen of fish furunculosis, in river water was investigated by laboratory-based experiments with two virulent strains (which were autoagglutinating) and two virulent strains (which were nonagglutinating). A difference in net electrical charge of A. salmonicida cells was detected by electrophoresis; cells of the viru...

The presence of calcium and humic substances or natural organic matter (NOM) in surface waters can cause severe fouling of nanofiltration (NF) membranes. Conditions of fouling were studied using a stainless steel stirred cell of volume 185 mL and a membrane area of 21.2*10-4m2 at a transmembrane pressure of 5 bar. Deposition of organic matter was determined by mass balance in feed and concentra...

in order to evaluate effects of water stress and foliar application humic acid on quantities and qualitative in borage, a field experiment was conducted as a split plots design with three replication in 2012 at agricultural research station, university of zabol. water stress treatments included control or 90 percent of field capacity (w1), 70 percent field capacity (w2) and 50 percent field cap...