Nine kinds of reactive dye solutions: Reactive K -2RL, H-E2R, X-6B1Y, HE-4G, X-3B, K-2R, H - E7B, X -4RN and S - F3B were treated by using Fenton reagent. While the concentration of dye is 400 mg/L, the FeSO4 dosage 1...Nine kinds of reactive dye solutions: Reactive K -2RL, H-E2R, X-6B1Y, HE-4G, X-3B, K-2R, H - E7B, X -4RN and S - F3B were treated by using Fenton reagent. While the concentration of dye is 400 mg/L, the FeSO4 dosage 100 -180 mg/L, H2O2 240 -540 mg/L, that is the stoichiometric numbers of Fe2+ and H2O2 are between 1: 9 - 1:12, pH = 3, reaction tune In, temperature 25℃, the colority removal efficiency reach more than 95%, the COD removal efficiency 65% -85%, and the TOC removal efficiency 70.2%. By comparing UV-VIS absorption spectrum before and after treatment, it further shows that decomposition effect of Fenton reagent on these nine kinds of reactive dyes is satisfactory.展开更多
Cyanobacterial blooms are ubiquitous in fresh and brackish eutrophic waters in India. The cyanotoxins produced by many bloom forming cyanobacteria severely affect the health of animals, fishes, birds and human beings....Cyanobacterial blooms are ubiquitous in fresh and brackish eutrophic waters in India. The cyanotoxins produced by many bloom forming cyanobacteria severely affect the health of animals, fishes, birds and human beings. Different physical and chemical factors contribute towards bloom formation. Ten bloom forming cyanobacteria were isolated from natural blooms of northern India. The strains were purified and enriched in the laboratory. The aim of this study was to understand the influence of iron on growth, pigmentation and antioxidative activity of enzymes-catalase and ascorbate peroxidase of bloom forming cyanobacteria. Results show that different strains of bloom forming cyanobacteria attain optimum growth at varied concentration of iron. The cyanobacterial strains like Synechocystis aquatalis, Merismopedia glauca, Anabaena variabilis and Anabaena iyengarii exhibit maximum growth at low iron concentration （2 pM） while some species require higher concentration of iron for their optimum growth namely, Arthrospira platensis show optimum growth at 10uM, and Nostocpaludosum shows maximum growth at 100uM concentration of iron. It was also noticed that chlorophyll and phycobiliprotein content also varies with change in iron concentration. The activity of antioxidative enzymescatalase and ascorbate peroxidase was noticed in all ten cyanobacterial strains. In the light of the findings, it seems that Arthrospira platensis possess maximum catalase and ascorbate peroxidase activity. Increment in concentration beyond optimum value leads to deterioration in the growth, pigment content and enzymatic activity of the cyanobacterial strains. Knowledge about the factors influencing growth of bloom forming cyanobacteria will help to work out ways for eradication of hazardous cyanobacterial blooms.展开更多
文摘Nine kinds of reactive dye solutions: Reactive K -2RL, H-E2R, X-6B1Y, HE-4G, X-3B, K-2R, H - E7B, X -4RN and S - F3B were treated by using Fenton reagent. While the concentration of dye is 400 mg/L, the FeSO4 dosage 100 -180 mg/L, H2O2 240 -540 mg/L, that is the stoichiometric numbers of Fe2+ and H2O2 are between 1: 9 - 1:12, pH = 3, reaction tune In, temperature 25℃, the colority removal efficiency reach more than 95%, the COD removal efficiency 65% -85%, and the TOC removal efficiency 70.2%. By comparing UV-VIS absorption spectrum before and after treatment, it further shows that decomposition effect of Fenton reagent on these nine kinds of reactive dyes is satisfactory.
文摘Cyanobacterial blooms are ubiquitous in fresh and brackish eutrophic waters in India. The cyanotoxins produced by many bloom forming cyanobacteria severely affect the health of animals, fishes, birds and human beings. Different physical and chemical factors contribute towards bloom formation. Ten bloom forming cyanobacteria were isolated from natural blooms of northern India. The strains were purified and enriched in the laboratory. The aim of this study was to understand the influence of iron on growth, pigmentation and antioxidative activity of enzymes-catalase and ascorbate peroxidase of bloom forming cyanobacteria. Results show that different strains of bloom forming cyanobacteria attain optimum growth at varied concentration of iron. The cyanobacterial strains like Synechocystis aquatalis, Merismopedia glauca, Anabaena variabilis and Anabaena iyengarii exhibit maximum growth at low iron concentration （2 pM） while some species require higher concentration of iron for their optimum growth namely, Arthrospira platensis show optimum growth at 10uM, and Nostocpaludosum shows maximum growth at 100uM concentration of iron. It was also noticed that chlorophyll and phycobiliprotein content also varies with change in iron concentration. The activity of antioxidative enzymescatalase and ascorbate peroxidase was noticed in all ten cyanobacterial strains. In the light of the findings, it seems that Arthrospira platensis possess maximum catalase and ascorbate peroxidase activity. Increment in concentration beyond optimum value leads to deterioration in the growth, pigment content and enzymatic activity of the cyanobacterial strains. Knowledge about the factors influencing growth of bloom forming cyanobacteria will help to work out ways for eradication of hazardous cyanobacterial blooms.
