Issue 4

Removal of Fe(II) and Mn(II) ions from aqueous solution by fungal biosorbent Aspergillus sp. TU-GM14immobilized on Detarium microcarpum matrix was investigated in this study. Effects of biosorption parameters pH, biosorbent concentration, bead size and equilibrium time on Fe(II) and Mn(II) ions sorption were also determined. Equilibrium was attained within in 3 hours while optimum Fe(II) and Mn(II) ions removal was observed at pH 6, 8 mm bead size, 2 g l^-1 spore load respectively. Adsorption capacity was described using Langmuir, Freundlich and BET isotherm models. The experimental data fitted best to the Freundlich model (R² 0.992 and 0.996 for Mn(II) and Fe(II) respectively). Favourable surface sorption process was described by Langmuir isotherm for both metals (Q_max 34 and 14 mg g^-1 for Mn(II) and Fe(II) ions) while the BET isotherm constant, B, described high metals sorption beyond the biosorbent surface in a multi-layer sorption process (4.8 and 9.0 for Mn(II) and Fe(II)  respectively). Results of the study showed that Aspergillus sp. TU-GM14 biosorbent can remove large quantities of Fe(II) and Mn(II) ions from solution in both surface and multi-layer sorption process with Detarium microcarpum acting as a cheap immobilization matrix.

This study was aimed to investigate the use of Mustard stalk as a cheap, eco-friendly adsorbent with support matrix for the immobilization of microbial cell and for subsequent removal of
2,4-dichlrophenol(2,4-DCP) from waste water. A comparative batch study between adsorption as well as simultaneous adsorption and biodegradation (SAB) of 2,4-DCP by mustard stalk immobilized Pseudomonas putida MTCC1194 have been studied in conical flask having concentration ranges of
2,4-DCP from 100 to 1000 mg l^-1 with adsorbent dose range 1 to 12 g l^-1 at pH range 2 to 9 and temperature range 28^°C to 35^°C, placed in an orbital shaker. The results of the batch studies showed that simultaneous adsorption and biodegradation (SAB) shows the maximum percent (91%) removal of 2,4-DCP as compared to simple adsorption (86 %) at optimum temperature 32 °C of adsorbent dose 10 g l^-1, and pH 6 with MSAC having particle size 0.24 mm. The equilibrium data for 2,4-DCP degradation sorbent systems were well fitted with Langmuir isotherm.

The protection and restoration of environment in an uncontrolled waste dumpsite require accurate estimation of subsurface pollution extent and intensity. The scope of the present analysis is to map the contamination in the aquifer of Eleona Attikis where METRO facilities (station, tunnel and depot) were built. Numerical modelling approaches were used to estimate environmental impacts of this project to soil and water resources in the greater region. The results have shown that the removal of buried solid wastes to construct METRO station and depot was crucial in order to eliminate negative impacts in soil and subsurface water resources. An impact assessment of hazardous solid wastes buried for many years in the aquifer was also performed. The findings of this analysis proved that the implementation of a large infrastructure project such as the one in Eleona Attikis Greece was environmentally beneficial for the region.

The main aim of this paper is to present a method for risk analysis using Bayesian process. The proposed method made it possible to estimate risk associated with the possibility of partial or total loss of the ability of water supply system operation. The paper proposes to consider two types of risk: the first type, associated with the possibility of interruptions in water supply and the second type, associated with the possibility of tap water contamination. 

In this work, three samples of nitrogen-doped TiO₂ prepared at different calcination temperatures (400, 450 and 500 °C) were applied for the adsorption of Direct Black 38. Kinetic studies about the adsorption of Direct Black 38 on nitrogen-doped TiO₂ were performed under different initial dye concentrations
(75-175 mg l^-1). Pseudo-first and pseudo-second order models were fitted with the experimental data. The results revealed that nitrogen-doped TiO₂ synthesized at 400 °C presented the more adequate characteristics for adsorption purposes, such as specific surface area of 151 m² g^-1. The adsorption kinetics agreed with the pseudo-second order model, at initial dye concentrations from 75 to 175 mg l^-1. The maximum adsorption capacity predicted by the pseudo-second order model was 138.3 mg g^-1, and was obtained using nitrogen-doped TiO₂ synthesized at 400 °C. In summary, these results revealed that nitrogen-doped TiO₂ is a good material for the removal Direct Black 38 from aqueous solutions by adsorption. 

Several adsorbents have been tried out by researchers to remove different pollutants from wastewater. However, the adverse effect of these biosorbents on the treated water and the possibility of leaching new pollutants to the treated water have not been investigated.  A batch technique was employed to study this phenomenon. Three agricultural wastes namely sawdust, dates stones and palm fibers were investigated. The possible leaching of total dissolved solids (TDS) and organic compounds in the form of chemical oxygen demand (COD) from these substances to water were investigated. The effect of water pH and particle size of these biosorbents on the extent of the leaching process was studied. The results indicate high release of both TDS and COD for the three biosorbents. A COD value as high as 230 mg l^-1 was obtained, while the highest TDS leached was 29 mg l^-1. DS was found to have the highest leaching ability, followed by SD and PF. The highest leaching was obtained at high pH and small particle size of the adsorbent.

The natural regeneration of Scots pine stands at the Sarakatsana location in the Pieria Mountains improved considerably after the removal of the dense ground vegetation followed mechanical soil scarification. The experimental design consisted of replications on scarified and non-scarified soil. The results four years after the experiment was set up showed that regeneration reached 59 seedlings m-2 in scarified and 7 seedlings m-2 in non-scarified soil. Soil scarification seems to have had a positive effect on the emergence and survival of naturally regenerated Scots pine. The negligible number of dead seedlings in the first two measurements could be due to the favourable site and/or good climatic conditions. Although the mother stand appears to be in a critical condition due to age and increased necrosis as a result of fungal attacks, there is still considerable potential for regeneration in terms of fructification and seed production. The study findings indicate that there can be new growth of Scots pine forest with the shelterwood method of natural regeneration in combination with soil scarification.

This paper analyzes the potential contribution of electric vehicles in greenhouse gas (GHG) emissions reduction over the next decade following a simulation procedure.  Emissions were assessed through a stepwise methodological approach at the transportation link level in the Hamilton Census Metropolitan Area (CMA). Firstly, different EV market penetration scenarios were introduced and compared to the base case scenario. Following these, the spatial distribution patterns of EVs were predicted using vehicle registration data for the Hamilton CMA as well as socioeconomic data obtained from census records. Properly modified matrices were used as input into our traffic simulation model in order to assign traffic on the network and estimate volumes for each of the links. To this end MOBILE 6.2C[1] was customized so as to compute the emission factors. The hourly emissions of each link were mapped in a GIS environment. We conclude that different utilization patterns result to varying spatial distributions of traffic related emissions in the links and even a modest adoption of EV technology may lead to their significant reduction.

The aim of the present study is to investigate the morphodynamic regime of the coastal area of Xylokastro (north coast of Peloponnese), in order to identify and evaluate the processes controlling its formation and evolution. Within this concept, a number of factors have been considered and evaluated; near-shore morphometry and granulometry along shore-normal profiles, the direction and potential volumes of long- and cross-shore sediment transport the decadal and future trends of coastline displacement, the available information for terrestrial sediment influx and the geological processes operating in the broader coastal region of Xylokastro (i.e. subaqueous slides) as well as human interference. On the basis of these results, the formation and evolution of this coastal stretch seems to be governed primarily by the neotectonic activity and relative change of sea level rise, and secondarily by the wave-induced near-shore sediment transport; the role of the latter could be enhanced substantially by human intervention (i.e. construction of marina, seafront walls). Moreover, the expected eustatic increase in sea level by the year 2100, could cause a coastline retreat up to 9 m (SLR=0.38 m) or >19 m (SLR≥1 m).