The concentration of ammonia nitrogen in a slaughterhouse wastewater sample was determined using Nessler's reagent spectrophotometry with four different pretreatment approaches. Comparison of the results shows that the concentrations increased in the following order: coagulation sedimentation < boric acid absorption < filtration < acidifying filtration. Boric acid absorption method is more favorable, and standard curve method (SCM) should be considered superior to standard addition method (SAM) in the present research.

The quantitative structure property relationship (QSPR) study was performed in this work to develop models to predict the normalized reaction rate constants for the reductive debromination of polybrominated diphenyl ethers (PBDEs) by zero-valent iron (ZVI). In order to consider the solvent effect, conductor-like polarizable continuum model (CPCM) was applied to optimize the geometries and obtain the molecular descriptors using the pseudopotential basis set. The prediction results with the inclusion of solvent effect are slightly better than that of the corresponding gas-phase calculations. The artificial neural network (ANN) model could be more satisfactory to predict the rate constants than the partial least squares regression (PLSR) and principal component analysis-multiple linear regression analysis (PCA-MLR) models.

Heavy metals (Hg, As, Pb, Cd, Cr, Cu) pollution in soil samples of Rosa sterilis planting areas located in Wudang District in Guiyang and Pingba County in Anshun was studied using a new evaluation theory of pollution loss rate, and following a series of methods for Rosa sterilis leaf including over standard rate, enrichment coefficient, single pollution index and comprehensive pollution index, the heavy metals pollution of the two Rosa sterilis planting areas was analyzed and evaluated. The results showed that the soil comprehensive pollution loss rate ranged from 12.73% to 28.26% in Wudang District samples, most of which belong to light pollution level. The comprehensive soil pollution loss rate of the sampling points in Pingba County varied from 9.68% to 16.10%, which belong to fairly clean level. Meanwhile, the experimental results for the Rosa sterilis leaf showed that the contents of Cr and Pb in both planting areas exceeded the permissible limit, while other elements were below the safe limit. The six heavy metal elements in Rosa sterilis leaf did not accumulate.

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Neutral PBDEs congeners and their corresponding radical anions were studied with the pseudopotential method of stuttgart group (SDD) effective-core potentials basis set for the bromine atoms and the all-electron basis set for all other atoms. The pseudopotential method can be used for compounds containing heavy elements with relativistic effects and can reduce the computational time. The quantitative structure property relationship (QSPR) study was also performed in this work to develop models to predict the normolized reaction rate constants for the reductive debromination of polybrominated diphenyl ethers (PBDEs) by zero-valent iron (ZVI). The partial least squares regression (PLSR), principal component analysis-multiple linear regression analysis (PCA-MLR), and back propagation artificial neural network (BP-ANN) approaches were employed for the QSPR study between the molecular descriptors and the logarithm of normalized reaction rate constants of fourteen selected BDE congeners. The results show that the ANN models could be more satisfactorily to predict the rate constants than the PLSR and PCA-MLR models.