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Volatile Organic Compounds (VOCs) are toxic for the environment and human health and their tendency to readily volatilize in the atmosphere can lead to problems connected to odours annoyance. Conventional VOCs gaseous emissions treatments entail the application of chemical-physical processes, only promoting the transfer of the contaminants from gas to liquid and/or solid phases. Advanced Oxidation Process (AOPs) and biological processes, conversely, support the oxidation of the organic pollutants, promoting their conversion into harmless and odourless compounds. The integration of booth processes is suggested to increase treatability of VOC. The research presents the application of an innovative treatment system composed by an AOPs pretreatment coupled with a bio-scrubbing unit for the abatement of VOCs, with the aim to increase the removal efficiency. The evaluation of the performance of the proposed system is discussed with reference to the analysis carried out using toluene as model substance. Different operating conditions have been analyzed and investigated to optimize the removal efficiency. The results show that the ozonation applied as pretreatment to the biological process may promote an increase of the pollutant biodegradability along with synergic effects due to the absorption of the ozone derived compounds into the culture growth, resulting in a significant enhancement of removal performances respect to the conventional biotechnologies. A toluene removal efficiency up to 95% were obtained under the investigated conditions.

High-speed railway (HSR) is severely affected by precipitation disasters. There are many studies on precipitation and precipitation disasters, most of which are precipitation and analysis of disasters caused by precipitation, and few explain climate changes caused by precipitation. This paper uses surface meteorological observation data within 90 km along the Jiangsu section of the Beijing-Shanghai HSR to study the characteristics of precipitation along the line in 2016 ~ 2018 and the characteristics of climate change before the occurrence of precipitation events. This paper presents that when air pressure along the HSR with a relatively low level and a higher probability of precipitation. The low temperatures in April, June and July are more likely to produce precipitation. Correlations analysis shows that the three types of precipitation events are different. The time scale of the correlation between temperature and pressure changes before the occurrence of mild to moderate precipitation events is farther, and the temperature and short-term pressure changes 6 hours before the occurrence of heavy precipitation events. In contrast, the air pressure and temperature within 2 hours before the occurrence of extreme precipitation change rapidly and have a strong correlation, which indicates the occurrence of extreme events.

The current study explores the capacities of Moringa oleifera (L), to overcome and/or tolerate oxidative stress induced by a saline substrate as a constraining factor. For this, Moringa seeds have been treated for 15 days after germination in vitro with increasing concentrations of NaCl, and specifically at 0 (control), 5; 7.5; 10; 12.5 and 15g l-1. Morpho-physiological and biochemical aspects were evaluated which were considered as probable indicators of tolerance or sensitivity to this stress. Our results reveal an increased synthesis of proline, lipids, proteins, CAT, GPX, APX, flavonoids, condensed tannins and a decrease in total polyphenols (-29.97%), mainly due to their high carbon cost. The state of degradation of the cell membranes was evaluated by the MDA assay, which increased by 91.25%. On the other hand, the evaluation of the oxidative damage caused by Reactive Oxidative Species (ROS) was detected by H2O2, which decreased by 37.89%. Additionally, our results revealed a disturbance of the germinative power of the seeds indicating moderate resistance to stress as it was manifested by the development of epicotyledonary axes, even under 15 g l-1 of NaCl without showing symptoms of stress or sensitivity. This result supports our hypothesis of the ability of the species to maintain or even improve its oxidative status.

This paper presents the results of an experimental study carried out in field-scale test cells in order to determine the effect of aeration and leachate recirculation on waste decomposition rate, solid waste characteristics, landfill gas composition and settlement in the landfill body. Four landfill test cells with the dimensions of 20 m x 40 m x 5 m were constructed in Komurcuoda Sanitary Landfill, Istanbul. Solid wastes representing Istanbul Asian side waste characteristics were landfilled in the test cells and they were operated simulating anaerobic (AN1), leachate recirculated anaerobic (AN2), semi-aerobic (A1) and aerobic landfilling (A2) methods. Alternative landfilling methods for accelerating solid waste stabilization in landfills were investigated by means of solid waste characteristics (elemental analysis, pH, moisture content, TOC, TKN, C/N ratio, volatile solid content (VS), biochemical methane potential (BMP), and stability index (SI) analysis), landfill gas components (CH4, CO2, O2, and H2S), temperature variations in landfill body, and landfill settlement. The study indicated that aeration and leachate recirculation accelerate biodegradation rate. Higher rates of MSW biodegradation eventually provide reduction in the contaminant life span of the landfill by achieving a high waste volume reduction in a relatively short duration than anaerobic test cells, decrease the cost of long term monitoring incurred with post-closure of landfill sites. In case of impossibility of aerobic landfilling based on the results of the cost benefit analysis, it was stated out that semi-aerobic landfilling technology is also a viable method in shortening the stabilization time and accelerating the landfill gas production.