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The distribution, stocks and fluxes of Mo were examined in a mountainous fir forest in Greece in two hydrological years. In both years, the fluxes of Mo in throughfall were lower than those in bulk deposition implying Mo retention and probably uptake by tree canopies. The Mo concentration was appreciable in soil solution but its fluxes were lower than those in throughfall. The Mo fluxes in both bulk and throughfall deposition were higher than those in litterfall, a finding that stresses the importance of the hydrological cycle for this metal. The Mo concentration in the older twigs in the standing trees were higher than the current year ones most probably due to the existence of dry deposition. The concentrations of total Mo in soils reflected the nature of the sedimentary rocks underlying the soil and increased with depth following the clay concentration gradient. The available (oxalate extractable) Mo in soils ranged from 3% to 14% of the total Mo. In terms of the stocks of Mo, the soil had by far the highest values in both total and available Mo. The needs of the fir plants for Mo uptake are covered by the available Mo in the mineral soil layers, whereas the Mo content in the organic horizon may not be adequate for this purpose.

This research examines the scope for reducing the air pollution caused by the transportation sector through the infusion of biofuel and antioxidants ensuring the partial replacement of conventional fuel. A four-stroke, direct-injection, multi-cylinder and constant-speed diesel engine was employed for the experimental analysis. The ternary fuel blend with a composition of 70% diesel fuel, 20% rubber seed oil and 10% of pentanol and sea weed extract in different ratios were blended to form B20, B20A1, B20A2 and B20A3. The experimental results showed smoke and carbon monoxide reduced by 4.71%, unburned hydrocarbons by 2.2 %. The NOx emission which was slightly higher compared to diesel but not higher than B20 for the blend B20A2 by 5%. The brake thermal efficiency was increased by 3.71% when compared to diesel fuel. Consequently, the B20A2 (5% seaweed and 5% pentanol additive with 70% diesel and 20% of rubber seed methyl ester oil) was found to be an environmentally biodegradable gasoline with the best emission properties. The study findings are quite promising for future which seeks towards zero emission with optimum quantity of biofuel to replace diesel.

In this study, activated sugar beet pulp as a biosorbent was used to remove Red-254 dye from aqueous solutions. The contact time, pH, biosorbent dosage and temperature were chosen as the parameters affecting the biosorption process. In the experiments, the batch adsorption technique was used. The isotherm, kinetic and thermodynamic parameters were calculated by using the data obtained from the experiments. The pseudo-second-order kinetic model and Langmuir isotherm model with R2 > 0.998 in all cases were individually fitted to experimental data. The maximum monolayer biosorption capacity was found to be 84.75 mg.g-1. Additionally, from the positive values of ∆Ho and the negative values of ∆Go, it can be expressed that biosorption processes were carried out with endothermic, physical adsorption, spontaneous and thermodynamically favorable. As a result, the sugar beet pulp, which can be found as waste from the sugar factories, can be used as biosorbent for the removal of Red 254 dye from aqueous solutions.

Anthracene and phenanthrene belong to a group of persistent environmental contaminants called PAHs. Evaluation of the structure of two selected PAHs i.e. anthracene and phenanthrene on their resistance to destruction by UV-activated PDS was the aim of this study. The authors focused on two aspects of this problem: - the role of the so-called ‘bay-region’, in the structure of phenanthrene, during PDS/UV oxidation - formation of substituted forms of these PAHs in the absence and presence of three nitrogen-containing compounds i.e. ammonia and nitrite or nitrate ions. Even though phenanthrene and anthracene have the same molecular formula, the difference in their ring assessment influences their degradability. Considering all the results, in all the cases anthracene was degraded faster and/or had a higher degradation rate. That proves phenanthrene to be more stable and resistant for degradation however comparison of PDS/UV systems vs. UV– irradiation alone confirms that the addition of PDS accelerates the degradation of anthracene and phenanthrene. Comparison of PDS/UV with the addition of three different nitrogen-containing compounds showed a significant difference between anthracene and phenanthrene. In the experiments with phenanthrene were observed additional peaks with an absorption maximum between 230-240 cm-1 which is characteristic of the nitro-group. Based on their absorption maximum and the addition of nitrogen-containing compounds, emerging by-products are assumed to be nitro-derivatives of phenanthrene. The results of GC/MS analysis suggest the possibility of formation of many compounds which can be formed from phenanthrene and are embedded on its skeleton. These analyzes also suggest the rearrangement of phenanthrene’s aromatic rings and formation new compounds.