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Journal of Quaternary Science, 27 (9), 901-910 The article of record as published may be located at http://dx.doi.org/10.1002/jqs.2579

Human health has been great threatened by acid wastewater containing thallium. The feasibility of start-up Sulfate-Reducing Bioreactor with acid wastewater containing thallium had been studied in the experiment. Sulfate-Reducing Bioreactor being started up successfully within 136 days with the method of high rate cultivation had been demonstrated. The results showed that the average removal efficiencies of sulfate achieved 25.21%, 61.08% and 93.39% during the lag phase, the increase phase and the steady phase of the Sulfate-Reducing Bioreactor, respectively. A preferable removal efficiency of thallium had been achieved, corresponding to the average thallium removal efficiency of 97.97% during the experimental period. However, COD in the acid wastewater mixture need further treatment due to removal efficiency of COD was not well, corresponding to the average removal efficiency of 26.12% in the steady phase of Sulfate-Reducing Bioreactor. The ratio of removal COD to sulfate reduced gradually and tented to be steady with the advance of start-up process of the bioreactor, which had been demonstrated that positive relevance was existed between the ratio of removal COD to sulfate and sulfate removal efficiency of the bioreactor.

Surface reaction in pyrite was investigated by using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Results found that the superficial hydroxyls were enhanced in the process of surface oxidation of pyrite but significantly decreased in the process of treating acidic solution containing thallium. Acidic liquid membrane formed by obvious surface dissolution and neutralization of carbonate within pyrite were further indicated by in situ attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. It was propounded that the neutralization of carbonate greatly influenced the release of thallium from pyrite through the experiment of pyrite treating Tl-containing acidic solution. A thallium release mechanism was proposed that the dissolution adsorption precipitation equilibrium of thallium was occurred, and this equilibrium was under the control of both neutralization reaction of carbonate and surface oxidation of pyrite and finally decided the release and migration of thallium.

This study dealed with the distribution and the origin of trace elements (Co, Cd, Mn, Ni, Zn, Tl and Pb) in two soil profiles from a site near a plant roasting pyrite for sulfuric acid production. Chemical partitioning of the trace elements showed that Tl and Pb in each individual extractable fraction(i.e. weak acid exchangeable, reducible and oxidizable)presented increasing trend upward through the depth in both profiles. Meanwhile, Co, Cd, Mn, Ni and Zn in all the above fractions revealed no general consistent trend across the depth. Results of the profile distribution of heavy metals in the chemical fractions combined with the principle component analysis indicated that the contamination of Tl and Pb is mainly from the percolation of pyrite slag particles in the studied soils, while the contamination of Co, Cd, Mn, Ni and Zn is predominantly due to the leaching of wastewaters in the soils.

The aim of this paper was to establish a method to determine ten kinds of PBDEs in human serum simultaneously. The linear range of measurement had good relationship (r>0.992). Blood samples were centrifuged and extracted. Hexane was respectively eluted through HLB column after serum was changed by urea and then purified with anhydrous sodium sulfate(Na2SO4)for analysis. Gas chromatography-mass spectrometry selected ion monitoring (GC-MSSIM)detection and quantitative analysis based on external standard were used to detect ten kinds of PBDEs in human serum simultaneously. The results indicated that the average recovery of the external standard was from 75.5% to 110%. The detection limit of the method was in the range of 0.001 ¨C 0. 05 ng, The detection method of ten PBDEscongeners in human serum was sensitive with high reproducible of satisfied recoveries.

Traffic conflict discrimination is a basic technology to evaluate road traffic safety and driving assistance. In order to improve the accuracy of the traffic conflict discrimination and to achieve the level of the automatic discrimination, the traffic conflict discrimination can be divided into two stages: occurance discrimination and severity discrimination. The integrated application of traffic conflict discrimination and kinematics theory will set up critical conflict regions model centering on speed, distance and angle, and thus achieve traffic conflict discrimination; Utilising machine learning method based on support vector machine to distinguish the severity of traffic conflict and then form a complete traffic conflict automatic discrimination method, finally, the practicality and accuracy of model were proved through examples. The investigation results indicated that the method could be adopted to distinguish the probability and the severity of conflict of traffic entities, which could provide theoretical basis to traffic conflict automatic discrimination technology.