The bioreduction of toxic chromium(VI) to sparingly soluble chromium(III) represents an environmentally friendly and cost-effective method for remediating Cr contamination. Usually, this bioreduction process is slow and requires the addition of quinone compounds as electron shuttles to enhance the reaction rate. However, the dissolved quinone compounds are susceptible to loss with water flow, thereby limiting their effectiveness.
View Article and Find Full Text PDFBioreduction of mobile Cr(VI) to sparingly soluble Cr(III) is an effective strategy for in situ remediations of Cr contaminated sites. The key of this technology is to screen Cr(VI)-resistant bacteria and further explore the sustainable enhancement approaches towards their Cr(VI) reduction performance. In this study, a total of ten Cr(VI)-resistant bacteria were isolated from a Cr(VI) contaminated site.
View Article and Find Full Text PDFNO production in aquaponics is an inevitable concern when aquaponics is developed as a future production system. In the present study, two attempts were applied to mitigate NO emission from aquaponics, i.e.
View Article and Find Full Text PDFAquaponics is a promising technology combining aquaculture with hydroponics. In this study, algal-bacterial consortia were introduced into aquaponics, i.e.
View Article and Find Full Text PDFBased on the investigation of phytoplankton and water body nutrient concentration in the ecology-monitoring area of Changli in summer from 2005 to 2013, the phytoplankton community structure was analyzed. The result showed that in recent 9 years, 3 phyla including 23 families, 39 genera and 105 species of phytoplankton were identified, in which 85.7% were diatoms and 13.
View Article and Find Full Text PDFTo study how global warming and eutrophication affect water ecosystems, a multiplicative growth Monod model, modified by incorporating the Arrhenius equation, was applied to Lake Taihu to quantitatively study the relationships between algal biomass and both nutrients and temperature using long-term data. To qualitatively assess which factor was a limitation of the improved model, temperature variables were calculated using annual mean air temperature (AT), water temperature (WT), and their average temperature (ST), while substrate variables were calculated using annual mean total nitrogen (TN), total phosphorus (TP), and their weighted aggregate (R), respectively. The nine fitted curves showed that TN and AT were two important factors influencing algal growth; AT limited growth as algal photosynthesis is mainly carried out near the water surface; N leakage of phytoplankton and internal phosphorus load from sediment explains why TN was the best predictor of peak biomass using the Monod model.
View Article and Find Full Text PDFPhosphate removal from aqueous waste streams is an important approach to control the eutrophication downstream bodies of water. A Fe(II) coordinated amino-functionalized silicate adsorbent for phosphate adsorption was synthesized by a post-grafting and metal cation incorporation process. The surface structure of the adsorbent was characterized by X-ray diffraction, N2 adsoropion/desoprotion technique, and Fourier transform infrared spectroscopy.
View Article and Find Full Text PDFJ Environ Sci (China)
February 2011
Activated carbon (AC) was considered to be an effective sorbent to control mercury in combustion systems. However, its capture capacity was low and it required a high carbon-to-mercury mass ratio. AC loaded with catalyst showed a high elemental mercury (Hg0) capture capacity due to large surface area of AC and high oxidization ability of catalyst.
View Article and Find Full Text PDFAn inorganic/organic hybrid adsorbent for phosphate adsorption was synthesized by introducing lanthanum (La) onto diamino modified MCM-41. The adsorbent was characterized by XRD, SEM, BET, TGA, and FTIR spectroscopy. A series of batch tests were conducted to investigate the influence of contact time, initial phosphate concentration, pH of the solution, and competitive ions on the phosphate adsorption capacity.
View Article and Find Full Text PDFJ Environ Sci (China)
July 2010
A series of lanthanum doped meosoporous MCM-41 (LaxM41, x is Si/La molar ratio) was prepared by sol-gel method. The surface structure of the materials was investigated with X-ray diffraction and N2 adsorption/desorption technique. The content of La in the materials was determined by ICP.
View Article and Find Full Text PDFSurface ozone and some meteorological parameters were continuously measured from June 2003 to May 2004 at urban Jinan, China. The levels and variations of surface ozone were studied and the influences of meteorological parameters on ozone were analyzed. Annual and diurnal ozone variation patterns in Jinan both show a typical pattern for polluted urban areas.
View Article and Find Full Text PDFTo study the physiological mechanisms in environment adaptation of alpine trees, the antioxidase activities and photosynthetic pigment contents in Larix principis-rupprechtii leaves along an altitudinal gradient from 1 600 m to 2 800 m at Pangquangou National Nature Reserve were investigated. The results showed that the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities in L. principis-rupprechtii leaves had the same change pattern along the altitudinal gradient, i.
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