Mercury removal from aqueous solution using petal-like MoS2 nanosheets

• Synthesized few-layered MoS₂ nanosheets via surfactant-assisted hydrothermal method. • Synthesized MoS₂ nanosheets show petal-like morphology. • Adsorbent showed 93% of mercury removal efficiency. • The adsorption of mercury is attributed to negative zeta potential (-21.8 mV). Recently, different nanomaterial-based adsorbents have received greater attention for the removal of environmental pollutants, specifically heavy metals from aqueous media. In this work, we synthesized few-layered MoS₂ nanosheets via a surfactant-assisted hydrothermal method and utilized them as an efficient adsorbent for the removal of mercury from aqueous media. The synthesized MoS₂ nanosheets showed petal-like morphology as confirmed by scanning electron microscope and high-resolution transmission electron microscopic analysis. The average thickness of the nanosheets is found to be about 57 nm. Possessing high stability and negative zeta potential makes this material suitable for efficient adsorption of mercury from aqueous media. The adsorption efficiency of the adsorbent was investigated as a function of pH, contact time and adsorbent dose. The kinetics of adsorption and reusability potential of the adsorbent were also performed. A pseudo-second-order kinetics for mercury adsorption was observed. As prepared MoS₂ nanosheets showed 93% mercury removal efficiency, whereas regenerated adsorbent showed 91% and 79% removal efficiency in the respective 2^nd and 3^rd cycles. The adsorption capacity of the adsorbent was found to be 289 mg/g at room temperature.     

The dynamics effect of green technology innovation on economic growth and CO2 emission in Singapore: new evidence from bootstrap ARDL approach

Environmental Science and Pollution Research - For an economy to excel in growth, there is usually a trade-off between financial development and environment deterioration. For a country like...     

Switching behaviors toward green brands: evidence from emerging economy

The aim of the current research was to recognize consumer attitude gap toward green brand by studying role of green consumer value and green brand equity toward the switching intention and purchase intention of consumers toward green brands. The current research employed quantitative research design and collected data through questionnaire from 331 respondents. The PLS-structural equation modeling was employed to analyze the structured relationships. The findings suggest green customer value is product of the three important factors namely green brand experiential risk, green brand experiential quality and green brand experience. Hence, these act as the main drivers of switching consumer behavioral intention toward the green products through consumer green brand equity. The research attempts to study the attitude–behavior gap in the green marketing literature by investigating the role which includes, green brand experiential risk, green brand experiential quality and green brand experience on customer value leading to green brand equity. The research provide an in-depth understating of attitude–behavior gaps and role of green customer value and brand equity that plays vital role in marketing campaigns and policy making to increase purchase intention of green eco-conscious products.

     

Does Globalisation Worsen Environmental Quality in Developed Economies?

We examine the causal relationship between globalisation and CO₂ emissions for 25 developed economies in Asia, North America, Western Europe and Oceania using both time series and panel data techniques, spanning the annual data period of 1970–2014. Because of the presence of cross-sectional dependence in the panel, we employ Pesaran’s Journal of Applied Econometrics 22, 265–312 (2007) cross-sectional augmented panel unit root (CIPS) test to ascertain unit root properties. The Westerlund Oxford Bulletin of Economics and Statistics 69, 709–748 (2007) cointegration test is also used to ascertain the presence of a long-run association between globalisation and carbon emissions. The long-run heterogeneous panel elasticities are estimated using the Pesaran Econometrica, 74(4), 967–1012 (2006) common correlated effect mean group (CCEMG) estimator and the Eberhardt and Teal Productivity analysis in global manufacturing production (2010) augmented mean group (AMG) estimator. The causality between the variables is examined by employing the Dumitrescu and Hurlin Economic Modelling, 29, 1450–1460 (2012) and Emirmahmutoglu and Kose Economic Modelling, 28, 870–876 (2011) Granger causality tests. The empirical results reveal that globalisation increases carbon emissions, and thus, the globalisation-driven carbon emission hypothesis is valid. This empirical analysis suggests insightful policy guidelines for policy makers using ‘globalisation’ as an economic tool for better long-run environmental policy.     

Airborne and allergenic fungal spores of the Karachi environment and their correlation with meteorological factors

Airborne fungal spores are well known to cause respiratory allergic diseases particularly bronchial asthma, allergic rhinitis, rhino-conjunctivitis and allergic broncho-pulmonary aspergillosis in both adults and children. In order to monitor and analyze airborne fungal flora of the Karachi environment, an aeromycological study was conducted using a Burkard 7-Day Recording Volumetric Spore Trap from January to December 2010. The data recorded from the Spore Trap was further analyzed for percent catch determination, total spores concentration, seasonal periodicities and diurnal variations. Cladosporium spp (44.8%), Alternaria spp. (15.5%), Periconia spp (6.1%), Curvularia spp (2.1%), Stemphylium spp (1.3%) and Aspergillus/Penicillium type (1%) emerged to be major components constituting more than 70% of the airborne fungal flora. Cladosporium, Curvularia and Stemphylium displayed a clear seasonal trend, while there were no clear seasonal trends for other fungal spore types. Diurnal variations were observed to be mainly having daytime maxima. Spearman Rank Correlation Coefficient analysis was conducted using various weather parameters. The various fungal types showed a negative correlation with heat index, dew point, wind velocity and wind chill. However, a positive correlation was found with humidity, rain and barometric pressure. In fact, Alternaria, Bipolaris and Periconia showed a negative correlation with temperature, while Cladosporium and Periconia showed a negative correlation with heat index, dew point, wind velocity and wind chill. The barometric pressure was positively correlated with Cladosporium. On the basis of these findings, it can be concluded that a number of fungal spores are present in the atmosphere of Karachi throughout the year, with certain atmospheric conditions influencing the release, dispersion, and sedimentation processes of some genera. It is expected that clinicians will use the identified fungal flora for diagnosis and treatment and/or adopt preventative measures for allergic individuals.     

Isolation of limonoid compound (Hamisonine) from endophytic fungi Penicillium oxalicum LA-1 (KX622790) of Limonia acidissima L. for its larvicidal efficacy against LF vector,Culex quinquefasciatus (Diptera: Culicidae)

Environmental Science and Pollution Research - Upon screening for novel and potential biocompounds with larvicidal activities, we successfully isolated hamisonine (HMSN) a limonoid compound from...     

Knowledge,behavior, and drivers of residents’ willingness to pay for a sustainable solid waste collection and management system in Mymensingh City,Bangladesh

Journal of Material Cycles and Waste Management - Excessive waste generation and ineffective waste management systems in developing cities have become a major challenge in achieving urban...     

People’s attitude towards willingness-to-pay for environmental protection in Pakistan

Environmental Science and Pollution Research - Recent environmental research has found that people with higher incomes and in more developed countries are more willing to pay (WTP) to protect their...     

Spillovers from global economic policy uncertainty and oil price volatility to the volatility of stock markets of oil importers and exporters

Economic policy uncertainty generally tends to induce a pessimistic view of future market behaviour. Furthermore, instabilities in global oil prices have serious implications for the economies of oil exporters and importers, due to their over-dependence on crude oil for revenue and production activities, respectively, and thereby on stock market indices. Against limited empirical evidence, this study examines the spillover effects from global economic policy uncertainty (GEPU) and oil price volatility to the volatility of the stock market indices of oil exporters and importers in both developed and emerging economies. The results show that the spillover effect from GEPU to oil exporters is relatively smaller than to oil importers, for both developed and emerging countries. Conversely, the volatility spillovers from oil prices to oil exporters are relatively larger than to oil importers, for both developed and emerging countries. Specifically, the volatility spillovers from oil prices to oil exporters (importers) in emerging countries are relatively stronger compared to oil exporters (importers) in developed countries. The findings indicate that the volatility of the stock markets of emerging countries is more sensitive to global factors such as GEPU and oil price volatility, and that oil exporters and importers in emerging economies are more sensitive to oil price volatility than oil exporters and importers in developed economies, which is in line with previous studies.

     

Evaluating the groundwater potential of Wadi Al-Jizi,Sultanate of Oman,by integrating remote sensing and GIS techniques

Environmental Science and Pollution Research - Groundwater resources are highly stressed due to their overuse, especially in the arid region. This study is aimed at discovering potential...