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The water quality chemical stability of Jinan's three waterworks (Quehua, Yuqing and Nanjiao waterworks) was analyzed through determination of several parameters affecting the chemical stability of water quality, including temperature, pH, Ca content, alkalinity, total hardness, total dissolved solids, chlorides, sulfates. For comprehensive and objective evaluation of the chemical stability of water, four water stability indexes LSI, RSI, AI, LR were used in this paper. The resulted index values indicated the corrosion in Jinan water distribution system may occur, and different source waters have different chemical characteristics. Yellow river water (Yuqing and Quehua) is high in chlorides and sulfates, while Nanjiao water is low in chlorides and sulfates. The improvement measure to chemical stability of water quality in Jinan City water distribution system included adding alkalinity, and blending water from different waters to reduce LR. The research proposed a way to control red water problem, which is meaningful to protect pipe works and improve tap water quality.

Based on the Jihogntan reservoir’s monitoring data from 2006 to 2009, eutrophication of Jihongtan reservoir was assessed. The result showed that the nutrition level of the Jihongtan reservoir was middle in recent years. The average concentration of chlorophyll-a(Chla) was higher in summer and autumn than in spring and winter. The correlation between concentration of Chla and some environmental factors was studied by statistical method, and seasonal variation of Chla and the extent of eutrophication were also analyzed. The results showed that the correlations between Chla and total nitrogen(TN), dissolved oxygen(DO) and transparency were significantly negative, and that between Chla and total phosphorus(TP), temperature(T) and potassium permanganate index(COD Mn) were significantly positive. The growth of phytoplankton was promoted by TP and TN at low concentrations, and inhibited by TN at high concentrations.

The microcystins (MCs) were released by alge cells rupture when cyanobacterial blooms occur in eutrophic freshwater body. MCs are toxic, which have been considered as potential tumor promoters. MCs usually exist in water by the level of ng/L - μg/L. In this paper, the pre-treatment techniques for determinating the trace MCs, including solid-phase extraction (SPE), solid-phase microextraction (SPME), immune affinity chromatography (IAC), cloud point extraction (CPE) are summarized. The advantages and disadvantages of each technique are presented. Chromatography analysis methods are also reviewed.

Abamectin is widely used in agriculture as an insecticide and in veterinary as an anti-parasitic agent, and has caused great environmental pollution by posing potential risk to non-target soil invertebrates and nearby aquatic systems. A bacterium designated GB-01, which was capable of degrading abamectin, was isolated from soil by enrichment culture method. On the basis of morphological, physiological and biochemical characteristics, combined with phylogenetic analysis of 16S rRNA gene, the bacterium GB-01 was identified as Burkholderia cepacia-like species. The bacterium GB-01 was able to utilize abamectin as its sole carbon source for growth, and could degrade more than 90% of abamectin at initial concentrations of 50 and 100 mg l(-1) in mineral salt medium in 30 and 36 h, respectively. The longer degradation cycle was observed with abamectin concentrations higher than 100 mg l(-1). Optimal growth temperatures and pH values with highest degradation rate were 30-35 degrees C and 7-8, respectively. Two new degradation products were identified and characterized by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) based mass spectral data and a plausible partial degradation pathway of abamectin was proposed. This is the first report in which an abamectin-degrading Burkholderia species isolated from soil was identified and characterized.

The chlorimuron-ethyl-degrading bacterium LW3 was isolated from contaminated soil and identified by 16S rRNA gene sequencing as Pseudomonas sp. When chlorimuron-ethyl was provided as the sole nitrogen source, the degradation efficiency in liquid medium was about 81.0% after 7 days of inoculation with strain LW3. The effects of chlorimuron-ethyl concentration and temperature on biodegradation were examined. Two metabolites of degradation were analyzed by LC/MS. Based on the identified products, strain LW3 seemed to be able to degrade chlorimuron-ethyl by cleavage of the sulfonylurea bridge. The inoculation of strain LW3 to chlorimuron-ethyl-treated soil resulted in a higher degradation rate than in uninoculated soil, regardless of the soil being sterilized or nonsterilized. This microbial culture has great potential for the bioremediation of soil contaminated with chlorimuron-ethyl.

A monocrotophos [dimethyl (E)-1-2-methylcarbamoylvinylphosphate or MCP] -degrading strain named as M-1 was isolated from sludge collected from the wastewater treatment pool of a pesticide factory and identified as Paracoccus sp. according to its morphology and biochemical properties and 16S rDNA sequence analysis. Using MCP as a sole carbon source, M-1 was able to degrade MCP(100 mg x L(-1)) by 92.47% in 24 h. The key enzyme(s) involved in the initial biodegradation of monocrotophos in M-1 was shown to be constitutively expressed cytosolic proteins and showed the greatest activity at pH 8.0 and 25 degrees C, with its Michaelis-Mentn's constant (K(m)) and maximum degradation rate (V(max)) of 0.29 micromol x mL(-1) and 682.12 micromol (min x mg)(-1) respectively. This degrading enzyme(s) was sensitive to high temperature, but kept high activity under alkaline conditions.

A rapid and accurate method for determining alkaloids from Coptis chinensis Franch, and Phellodendron amurense Rupr, decocted together in Baitouweng decocta was established. Experiments were carried out on a self-assembled capillary electrophoresis system. The experimental conditions were as follows: 75 microns i.d. x 50 cm fused silica capillary, 0.05 mol/L Na2B4O7-CH3OH (85:15, V/V) as buffer, applied voltage 14 kV and detection wavelength 232 nm. In addition, the concentration of ethanol in the extraction solvent was optimized. Experimental results showed that ethanol-water (30:70, V/V) was the ideal solvent to extract the main effective ingredients from Coptis chinensis Franch. and Phellodendron amurense Rupr. decocted together in Baitouweng decocta. Berberine and palmatine had good linearities in the range of 15.0 mg/L-65.0 mg/L and 12.5 mg/L-50.0 mg/L respectively, and their average recoveries were 95.5%-104% (RSD 2.7%-6.9%) and 92.1%-103% (RSD 4.5%-6.7%) respectively.

Solid-phase microextraction (SPME) is a technology with functions of sampling, extraction and concentration based on adsorption/absorption-desorption equilibrium between coating and sample. The recent development of SPME is reviewed. Studies on the in-tube-SPME technology, novel extraction probes and its coupling with other analytical technologies are summarized.