Assessment of radiological hazard of NORM in Margalla Hills limestone, Pakistan

Studies on naturally occurring radioactive material (NORM) in the limestone from the Margalla Hills have been carried out by measuring gamma activity and to access its radiological implications if any. For data acquisition, a High-Purity Germanium detector was employed. The activity concentrations of (226)Ra, (232)Th, and (40)K were found to be 14.32?±?0.24, 2.05?±?0.04, and 13.80?±?0.20 Bq kg(-1), respectively. These values are relatively lower as compared to that in the limestone of other countries and much lower than the values reported for the natural building stones. The average specific activities due to (226)Ra were found to be higher when compared with (40)K and (232)Th. Indices of radium equivalent activity (Ra(eq)), internal hazard (H(in)), indoor absorbed gamma dose rate (D(R,)), and corresponding annual effective dose (E(eff)) were also determined for the limestone-made rooms. All of these indices were found to be in the lower ranges. The Margalla Hills limestone does not pose any excessive radiological health hazard as a building material and in industrial uses for a common man.     

Removal of cyanide in aqueous solution by oxidation with hydrogen peroxide in presence of activated alumina

This work is dedicated to the removal of free cyanide from aqueous solution by oxidation with hydrogen peroxide H₂O₂ catalyzed by neutral activated alumina. Effects of initial molar ratio [H₂O₂]₀/[CN^?]₀, catalyst amount, pH, and temperature on cyanide removal have been examined. The presence of activated alumina has increased the reaction rate showing thus, a catalytic activity. The rate of removal of cyanides increases with rising initial molar ratio [H₂O₂]₀/[CN^?]₀ but decreases at pH 10 to 12. Increasing the alumina amount from 1.0 to 30 g/L has a beneficial effect, and increasing the temperature from 20 °C to 35 °C improves cyanide removal. The kinetics of cyanide removal has been found to be of pseudo-first-order with respect to cyanide and the rate constants have been determined.     

Chemical and isotopic investigation of groundwater in Tahta region,Sohag-Egypt

Chemical and isotopic investigations indicate that the recharge source for the groundwater in the Tahta district, adjacent to the Nile, is mainly from the Nile water seeping from irrigation channels. The water's chemical type is sodium bicarbonate, with values of oxygen-18 and deuterium close to that of Nile water. Another minor source of recharge to the far west of the Nile bank is palaeowater. This water's chemical type is sodium sulphate and sodium chloride. The change of water quality in some groundwater samples could be due to the extensive use of fertilizers to improve soil characteristics in new reclamation projects. In addition, these wells are slightly depleted in oxygen-18, deuterium and tritium. Recommendations for the periodic monitoring of groundwater quality for proper use are given.     

Artificial intelligence for waste management in smart cities: a review

Environmental Chemistry Letters - The rising amount of waste generated worldwide is inducing issues of pollution, waste management, and recycling, calling for new strategies to improve the waste...     

Sustainable consumption profile differences among Brazilian regions

Brazil is a vast country and there are several scientific studies reporting sustainable behavior in its different regions. Since methodologies used in these studies differ from one another, it is hard to compare them. This paper aims to identify whether differences in sustainable behavior occur in different Brazilian regions and what differences can be identified. Through a web survey, we analyzed data from 1,489 participants, from four different regions. We identified two factors (behavior and search for information), and analyzed the differences through multivariate analysis of variance. The Northeast region had a higher score for “search for information”, while Southern regions performed better on “behavior.” The Midwest region had the worst performance for both factors. The reasons for such differences may be greatly influenced by the social/cultural context of each region. The results also show that consumers still do not use their power of choice to pressure companies to become more sustainable.     

Environment and Mobility: A View from Four Discourses

Debate and literature on the link between degrading environments and human mobility has been increasing exponentially. There is little concrete evidence, however, of efforts or policies that support the management of environmentally influenced mobility. Through discourse analysis using Q-methodology, this research aimed to scrutinize the standoff between opposing views under a fresh lens. One-hundred and ninety-seven experts from 49 nations completed an on-line survey asking them to sort, by level of agreement, 42 statements gleaned from the literature concerning the environment-mobility nexus. Four very different discourses emerged: determined humanists, benevolent pragmatists, cynical protectionists, and critical realists. The complexity of these discourses helps explain the stalemate while confirming the inappropriateness of one-sided terminology and linear quantifications. Despite diametrically opposed viewpoints, experts unanimously agree that human mobility is connected to environmental change. Dissection of these social perspectives builds a new foundation for the Rio+20 analysis and policy deliberations related to environmentally influenced human mobility.     

A GIS-based DRASTIC vulnerability and net recharge reassessment in an aquifer of a semi-arid region (Metline-Ras Jebel-Raf Raf aquifer, Northern Tunisia)

This paper aims to elaborate new generic DRASTIC aquifer vulnerability maps of the coastal aquifer of Metline-Ras Jebel-Raf Raf (Northeast of Tunisia) using the GIS technique, making the data analyses easier to handle and providing better capabilities of dealing with large spatial data. A similar study was carried out in 1999 in the same aquifer using a method based on the soil water balance equation to determine the net recharge parameter. Unfortunately, the lack of data in the study area made the results unsatisfactory. By applying the Williams and Kissel equation and the Rao relationship, we intend to demonstrate that we could correctly evaluate the net recharge parameter. Moreover, new data related to the aquifer hydraulic conductivity, the soil cover and the vadose zone lithology have become available, and allowed us to elaborate suitable DRASTIC maps.     

Efficient removal of the antibiotic Cefixime on Mg0.3Zn0.7O under solar light: kinetic and mechanism studies

Environmental Science and Pollution Research - The heterogeneous photocatalysis is known to provide significant degradation and mineralization of emerging contaminants including antibiotics. For...