How COVID-19 shock will drive the economy and climate? A data-driven approach to model and forecast

Environmental Science and Pollution Research - The pandemic shock puts the world on quarantine and paused economic operations that affected energy consumption and economic output. This study...     

Carbon and polymer-based magnetic nanocomposites for oil-spill remediation—a comprehensive review

Environmental Science and Pollution Research - Oil spills are a major contributor to water contamination, which sets off a significant impact on the environment, biodiversity, and economy....     

Magnetic nanocomposites for sustainable water purification—a comprehensive review

Numerous contaminants in huge amounts are discharged to the environment from various anthropogenic activities. Waterbodies are one of the major receivers of these contaminants. The contaminated water can pose serious threats to humans and animals, by distrubing the ecosystem. In treating the contaminated water, adsorption processes have attained significant maturity due to lower cost, easy operation and environmental friendliness. The adsorption process uses various adsorbent materials and some of emerging adsorbent materials include carbon- and polymer-based magnetic nanocomposites. These hybrid magnetic nanocomposites have attained extensive applications in water treatment technologies due to their magnetic properties as well as combination of unique characteristics of organic and inorganic elements. Carbon- and polymer-related magnetic nanocomposites are more adapted materials for the removal of various kinds of contaminants from waterbodies. These nanocomposites can be produced via different approaches such as filling, pulse-laser irradiation, ball milling, and electro-spinning. This comprehensive review is compiled by reviewing published work of last the latest recent 3 years. The review article extensively focuses on different approaches for producing various carbon- and polymer-based magnetic nanocomposites, their merits and demerits and applications for sustainable water purification. More specifically, use of carbon- and polymer-based magnetic nanocomposites for removal of heavy metal ions and dyes is discussed in detail, critically analyzed and compared with other technologies. In addition, commercial viability in terms of regeneration of adsorbents is also reviewed. Furthermore, the future challenges and prospects in employing magnetic nanocomposites for contaminant removal from various water sources are presented.

     

Faecal and nitrate contamination in the groundwater of Mardan district,Pakistan

Environmental Geochemistry and Health - This study aimed to determine the status of groundwater contamination with faecal coliform and nitrate in the rural areas of Mardan district, Pakistan. Both...     

Determinants of privatized solid waste management service provision in Lagos

The growing popularity of privatized solid waste management service in least developed countries warrants an exploration of factors that are likely to impact on its sustainability. This study takes integrated solid waste management approach by analyzing relevant issues on both market sides. We use a three step theme development sequence to analyze the data obtained on service providers through library research, observations and interviews. This was followed by an opinion survey on the demand side to elicit households’ support for service improvement. Findings show that source-separation issues, government enforcement, market segmentation, financial issues and waste disposal issues are key factors influencing improved service provision. Meanwhile, on the demand side, we found that households are willing to support proposed regulatory improvement in service provision. Thus, we suggest industrial stakeholders to consider the aforementioned supply side issues in designing future service improvements that will take advantage of existing demand side feasibility.     

Synthesis of Chitosan@activated Carbon Beads with Abundant Amino Groups for Capture of Cu(II) and Cd(II) from Aqueous Solutions

In this study, chitosan and bio-based activated carbon obtained from sugarcane bagasse biowaste were used for the synthesis of efficient sorbent for Cu(II) and Cd(II) ion via precipitation method. The prepared material was enriched with amino groups through grafting tetraethylenepentamine and tested for heavy metal remediation from water samples. The influence of pH was investigated showing optimum sorption at pH 6 for Cu(II) and Cd(II). Sorption tests, explained by means of the most common sorption models, evidenced that the best performances were reached pointing out the promising application of the prepared sorbent for water purification treatments: Uptake kinetics are relatively fast: the equilibrium was reached within 140 min; and the kinetic profiles were preferentially fitted by the pseudo-second order rate equation. Sorption isotherms are fitted by Langmuir equation. The sorbent showed high metal ion sorption capacity with negligible influence of ion strength. The maximum sorption capacities reached 3.44 and 2.38 mmol g^??1 for Cu(II) and Cd(II), respectively at 298 K. Thermodynamic parameters were evaluated through variation of temperature. The sorption is unfavorable at elevated temperatures. Metal ions were successfully desorbed using 1 M HNO₃ solution.     

The depositional setting of the Late Quaternary sedimentary fill in southern Bannu basin,Northwest Himalayan fold and thrust belt,Pakistan

Geostatistical variogram and inversion techniques combined with modern visualization tools have made it possible to re-model one-dimensional electrical resistivity data into two-dimensional (2D) models of the near subsurface. The resultant models are capable of extending the original interpretation of the data to depict alluvium layers as individual lithological units within the 2D space. By tuning the variogram parameters used in this approach, it is then possible to visualize individual lithofacies and geomorphological features for these lithologic units. The study re-examines an electrical resistivity dataset collected as part of a groundwater study in an area of the Bannu basin in Pakistan. Additional lithological logs from boreholes throughout the area have been combined with the existing resistivity data for calibration. Tectonic activity during the Himalayan orogeny uplifted and generated significant faulting in the rocks resulting in the formation of a depression which subsequently has been filled with clay-silt and dirty sand facies typical of lacustrine and flood plain environments. Streams arising from adjacent mountains have reworked these facies which have been eroded and replaced by gravel-sand facies along channels. It is concluded that the sediments have been deposited as prograding fan shaped bodies, flood plain, and lacustrine deposits. Clay-silt facies mark the locations of paleo depressions or lake environments, which have changed position over time due to local tectonic activity and sedimentation. The Lakki plain alluvial system has thus formed as a result of local tectonic activity with fluvial erosion and deposition characterized by coarse sediments with high electrical resistivities near the mountain ranges and fine sediments with medium to low electrical resistivities towards the basin center.     

Date palm (Phoenix dactylifera L.) leaves as biomonitors of atmospheric metal pollution in arid and semi-arid environments

The leaves of date palms were evaluated as a possible biomonitor of heavy metal contamination in Ma’an city, Jordan. Concentrations of (Fe), (Pb), (Zn), (Cu), (Ni), and (Cr) were determined in washed and unwashed leaves and soil samples collected from different sites with different degrees of metal contamination (urban, suburban, industrial, highway and rural sites); separate leaves were taken from outside the city to be used as a control sample. Samples collected from industrial sites were found to have high concentrations of all metals except those of Cu, Ni and Pb, which were found at high levels in the highway site samples which is associated with the road traffic. The difference between unwashed and washed samples showed that metal pollutants exist as contaminants, particularly Pb, Zn and Ni, which varied in concentration, depending on the source of the metal.     

Degradation of aldrin and endosulfan in rotary drum and windrow composting

Removal efficiencies, kinetics and degradation pathways of aldrin, endosulfan α and endosulfan β in vegetable waste were evaluated during rotary drum and conventional windrow composting. The highest percentage removal of aldrin, endosulfan α and endosulfan β in rotary drum composting was 86.8, 83.3 and 85.3% respectively, whereas in windrow composting, it was 66.6%, 77.7% and 67.2% respectively. The rate constant of degradation of aldrin, endosulfan α and endosulfan β during rotary drum composting ranged from 0.410–0.778, 0.057–0.076 and 0.009–0.061 day^?1 respectively. The pathways of degradation of these pesticides in composting process were proposed. Metabolites dieldrin and 1 hydroxychlorodene formed during composting of aldrin in the vegetable waste indicated the occurrence of epoxidation reaction and oxidation of bridge carbon of aldrin containing the methylene group. Formation of chloroendic acid and chloroendic anhydride during composting of endosulfan containing vegetable waste support the occurrence of endosulfan sulfate and dehydration reaction respectively.