Allelopathically inhibitory effects of eucalyptus extracts on the growth of Microcystis aeruginosa.

Microcystis aeruginosa (M. aeruginosa), as the dominant algae in eutrophic water bodies, has caused a serious harm to the local eco-environment. A biological tool, employing allelopathic inhibitory of eucalyptus to control M.

Evaluation of the use of eucalyptus to control algae bloom and improve water quality.

Lakes represent an important source of drinking water resource for human beings. The presence of harmful algae blooms can pose a serious threat to lakes water quality. This study explored the feasibility of using eucalyptus plants and leaves extracts for controlling algae proliferation in an aquatic milieu.

A long-term static immersion experiment on the leaching behavior of heavy metals from waste printed circuit boards.

Printed circuit boards (PCBs) are the main components of electrical and electronic equipment (EEE). Waste PCBs contain several kinds of heavy metals, including Cu, Pb and Zn. We characterize the leaching of heavy metals (Cu, Pb, Zn and Ni) from waste PCBs in a pH range of 3.

[Explore the spatial and temporal patterns of water pollution in the Yincungang canal of the Lake Taihu basin, China].

Two high-density snap-shot samplings were conducted along the Yincungang canal, one important tributary of the Lake Tai, in April (low flow period) and June (high flow period) of 2010. Geostatistical analysis based on the river network distance was used to analyze the spatial and temporal patterns of the pollutant concentrations along the canal with an emphasis on chemical oxygen demand (COD) and total nitrogen (TN). Study results have indicated: (1) COD and TN concentrations display distinctly different spatial and temporal patterns between the low and high flow periods.

Effect of C/N ratios on the performance of earthworm eco-filter for treatment of synthetics domestic sewage.

Purpose: The performances of filter systems that use earthworms and plants, combined with earthworm eco-filter (EE) systems in treating synthetic domestic sewage (SDS) with different C/N ratios, were investigated for a 9-month period.

Methods: The effects of the combination of filters, earthworms, plants, as well as the combination of earthworms and plants on SDS nutrient removal efficiency were separately investigated to select the optimum system for treating SDS. The results of the current study could be used to determine how treatment performance responds to different C/N ratios and to explain and predict the performance of an operating EE system.

[Effect of TS loading rates of biogas residue of Spartina alterniflora for secondary anaerobic digestion].

Biogas residue of Spartina alterniflora treated by NaOH solution for 48h at room temperature was used for secondary anaerobic digestion with TS loading rates were 8%, 10%, 12% at (35 +/- 1) degrees C. The biogas yield, pH, and volatile fatty acid (VFA) were analyzed during the anaerobic digestion. The peak of daily gas production were 10, 14, 13 mL x g(-1) and the rates of cumulate gas production were 217, 227, 228 mL x g(-1) respectively.

[Adsorption behavior and influence factors of p-nitroaniline on high surface area activated carbons prepared from plant stems].

Low-cost and high surface area microporous activated carbons were prepared from Spartina alternilora and cotton stalk with KOH activation under the conditions of impregnation ratio of 3.0, activation temperature at 800 degrees C and activation time of 1.5 h.

[Nitrogen removal in earthworm ecofilter treating domestic wastewater].

The removal efficiency of different forms of nitrogen was studied in earthworm ecofilter treating domestic wastewater, and the mechanisms were discussed. Results indicated that, the major form of total nitrogen (TN) in influent water and effluent water were existed as ammonia-nitrogen (NH4+ -N) and nitrate-nitrogen (NO3- -N), respectively. NH4+ -N /TN in influent water and NO3- -N /TN in effluent water were 83.

[Speciation distribution characters of heavy metals in waste printed circuit boards].

The environmental availability of heavy metals from the waste printed circuit boards (PCBs) were studied through BCR's three-stage extraction procedures from EU and Tessier's five sequential extraction procedures. The results show that the heavy metal extraction rates with BCR's procedures are higher than that with Tessier's from waste PCBs. There are significant differences in fraction distributions of heavy metals in PCBs.

[Different leaching procedures for heavy metal toxicity of waste PCBs].

The purpose of this paper is to evaluate the hazardous of heavy metals of waste printed circuit boards (PCBs) by using four kinds of methods (GB 5086.1-1997, GB 5086.2-1997 from China and 1311 (TCLP), 1312 (SPLP) from USA), and the four kinds of methods are compared to choose a better way to identify toxicity characteristics of waste PCBs.