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Organochlorine pesticides (OCPs) including Hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in surface water of Lake Baiyangdian were determined to assess the potential health risk when using as drinking water for children and adults. The concentration of HCHs and DDTs in surface water were in the range of 2.74-11.50 ng L-1 and 3.48-16.88 ng L-1, respectively. Compared with similar results reported around the world, the level of OCPs in this study was in the mid-range. The analysis of health risk indicated that risks from OCPs in most part of the lake would not be risky to human health according to the acceptable risk level, while carcinogenic effects caused by α-HCH might occur if drinking water from Nanliuzhuang (NLZ) and Laowangdian (SCD). α-HCH and β-HCH were the dominating factors for carcinogenic and non-carcinogenic risks, respectively. Risks of OCPs for children were much higher than those caused by OCPs for adults.

The burial characteristics and risks of 16 polycyclic aromatic hydrocarbons (PAHs) in core sediments from Baiyangdian Lake were investigated through gas-chromato graphy/mass spectrometry. The total concentrations of the 16 PAHs ranged from 39.48-1877.75 ng g −1 . The low-molecular-weight PAHs (two-to three-ring PAHs) were the dominant species, contributing 40.10-92.18% to the total PAHs, with a mean of 71.01%. Based on the observed molecular indices and on principal component analysis, the PAHs inputs were initially dominated by biomass and coal combustion, and atmospheric deposition and surface runoff could be the major transport pathways. The contaminated source characteristics, hydrodynamic condition, and sediment textural composition are the key factors affecting the distribution and source of PAHs. By conducting a risk quotient analysis between specific PAH concentrations and their corresponding sediment quality values, the top layer sediments were found to have a potential biological impact and relatively high toxicity. However, such impact should have no impairment. The toxic potency of PAHs in Baiyangdian Lake could be described by using the toxic equivalent of benzo[a]pyrene.

For getting the effectiveof application in dissipation dust law with particle motion equation atcoal handling system of belt machine tail, must be to proceed related numerical simulation in the way of dust particles motion incoal handling system of belt machine tail and dust concentration of diffusion inoperation space. Application particlemotion equation theory for numerical simulation to coal dustparticles, obtained dust coal dissipation law in coal handling system, at thesame time combine with the data of the field test of dust concentration andfallout dispersion for analyzing and comparing. The results of comparison showthat: the data of numerical simulation with particle motion equationin coal dust dissipation law is coincide with reality dissipation law. Accordingto the conclusion of this research, it is provides theoretical basis forprevention and treatment in coal mine of coal handling system of dustdissipation.