The aim of this article is the study of the potential relationships between PAHs contamination, physicochemical parameters, and microbial activity in industrial soils. The research was based on two series of measurements. The first was conducted in June 2013 and the second in November 2013. Samples used in study were collected from the area of fuel handling and a loading station, located in the Silesia region of Poland. All collected samples were characterized by the following analytical procedures: PAHs content analysis, the basic physical and chemical parameters determinations (pH, CEC, humic acids content, TC, TN, TP) and microbial activity analysis. The obtained results were also subjected to statistical analysis, based on the Pearson's correlation coefficient calculations.
Results collected during described above procedure show that: the PAHs content was highly positively correlated with C and N contents (p < 0.001) and moderately correlated with humic acids and P contents (p < 0.01). This phenomenon confirms the thesis that the increase of soil organic matter content promotes accumulation of hydrophobic organic compounds such as PAHs. Microbiological analysis shows that bacteria from the mesophilic group are most resistant to PAHs contamination. This information indicates that the organisms belonging to this group should be considered as potentially useful in the soil bioremediation processes. 相似文献
Isolated aromatic interactions in designed octapeptide β‐hairpin scaffolds display a near‐universal T‐shaped face‐to‐edge geometry in all positional permutations, with the exception of aryl‐Trp interactions. The heterogeneous asymmetric indole ring of Trp competes for a “shielding” face geometry, which lowers the scaffold stability in FtE aryl‐Trp pairs. Assessment of the contributions of aryl pairs (in the absence of solvent‐driven interactions) to the overall β‐hairpin structure reveals the superiority of Trp‐Phe and Trp‐Tyr contributions over the well‐established scaffold stabilization by Trp‐Trp. 相似文献
The effect of aliphatic and aromatic hydrocarbons on surfactant micellar growth has been investigated by viscosity measurements
at 40°C. Aqueous and aqueous KBr (0.1 M) solutions of 0.1 M cetylpyridinium bromide (CPB) showed that the viscosity behavior
changed substantially in the presence of KBr. This is attributed to favorable conditions produced by KBr that assist micellar
growth by addition of hydrocarbons. Reasons for the effectiveness of the solubilized hydrocarbons are suggested and supported
by theoretical arguments. The causes of viscosity decrease at higher aromatic hydrocarbon concentrations are also explained.
Micellar growth with soluble aromatic/aliphatic hydrocarbons could also be initiated if a moderate salt concentration is present
in CPB micellar solutions. The chainlength, solubilization site, and molar volume of the soluble hydrocarbons all affect the
bulk viscosity of the solution. Such surfactant and hydrocarbon combinations may find use in micellar-enhanced ultrafiltration
of benzene and its derivatives, but it should be kept in mind that micellar shape may change and be more curved at higher
benzene derivative concentrations. 相似文献