An assessment on the recycling opportunities of wastes emanating from scrap metal processing in Mauritius

This paper presents an assessment on the wastes namely slag, dust, mill scale and sludge resulting from scrap metal processing. The aim of this study is to demonstrate that there are various ways via which scrap metal processing wastes can be reused or recycled in other applications instead of simply diverting them to the landfill. These wastes are briefly described and an overview on the different areas of applications is presented. Based on the results obtained, the waste generation factor developed was 349.3 kg per ton of steel produced and it was reported that slag represents 72% of the total wastes emanating from the iron and steel industry in Mauritius. Finally the suitability of the different treatment and valorisation options in the context of Mauritius is examined.     

Bio-mediated silver nanoparticle synthesis: mechanism and microbial inactivation

Even though plenty of literature is available on the biosynthesis of metal nanoparticles, there are serious lacunae on the mechanisms of their formation. In the present study, the mechanism of formation of mono-crystalline silver nanoparticles using a fruit extract of the ornamental tree Thevetia peruviana is emphasized, i.e. how the pH of the reaction mixture affected reaction kinetics and size of the nanoparticles. The facilitation of formation of Ag₂O at higher pH resulted in a faster rate of particle formation. The diameter of the bare particles at neutral pH determined by field emission scanning electron microscopy and the hydrodynamic diameter determined by dynamic light scattering were 53 and 104 nm, respectively. The silver nanoparticles exhibited good inactivation of Escherichia coli due to participation of free radicals as evidenced by electron spin resonance spectroscopy.     

Photocatalytic degradation of p-nitrophenol using biologically synthesized ZnO nanoparticles

Environmental Science and Pollution Research - The present work deals with the photocatalytic degradation of p-nitrophenol as it is a United States Environmental Protection Agency-listed priority...     

Experimental investigation on CO2 absorption and physicochemical characteristics of different carbon-loaded aqueous solvents

Environmental Science and Pollution Research - The anthropogenic carbon dioxide (CO2) denseness in the earth’s atmosphere is increasing day-to-day by combusting fossil fuels for power...     

Ground water quality in the Kathmandu valley of Nepal

A study was undertaken to assess the quality of groundwaters in the Kathmandu Valley, Nepal. The groundwater samples were randomly collected from shallow well, tube well, and deep-tube wells located at different places of Kathmandu, Lalitpur, and Bhaktapur districts in the Kathmandu valley. Physical, chemical, and microbiological parameters of the samples were evaluated to estimate the groundwater quality for drinking water. It was found that the groundwater in the valley is vulnerable to drink due to presence of iron and coliform bacteria. Iron was estimated to be much higher then the acceptable limit of World Health Organization (WHO) drinking-water quality guidelines (1.9 mg/L). Total coliform bacteria enumerated in groundwaters significantly exceeded the drinking-water quality standard and observed maximum coliform (267 CFU/100 mL) in shallow wells. The electrical conductivity and turbidity were found to be 875 ??S/cm and 55 NTU, respectively, which are above the WHO recommendations for drinking water guidelines. However, pH value was measured within the acceptable limit. Arsenic, chloride, fluoride, and hardness concentrations were found to be in agreement with the recommendations of WHO drinking-water quality guidelines.     

Co-benefits of a carbon tax in Nepal

This paper analyzes the co-benefits of introducing a time variant carbon (C) tax scheme in Nepal, a hydropower resourceful country, by using a bottom up integrated energy system model based on the MARKet ALlocation (MARKAL) framework with time horizon of 2005–2050. It discusses the effects of C tax on energy mix, environmental emissions, energy supply security, energy efficiency, energy system cost, and employment benefit. The study shows that the C tax (that gradually increases from US13/tCO < sub > 2 < /sub > e in 2015 to US 13/tCO₂e in 2015 to US 200/tCO₂e by 2050) results in a reduction of the cumulative emission of greenhouse gases by 83.9 million tons CO₂e (12%) as compared to that in the base case. With the introduction of the C tax, there would be a need for additional hydropower capacity of 945 MW by 2050 as compared to the capacity in the base case. The emission of local pollutants consisting of sulphur dioxide (SO₂), nitrogen oxides (NO_x) and non-methane volatile organic compound (NMVOC) in 2050 would be reduced by 12%, 7% and 1% respectively under the C tax scenario. Total amount of imported energy would decrease by 13%, which corresponds to a reduction in discounted net fuel import cost by 5% during the study period. Furthermore, the C tax would result in new employment generation of 151 thousand man-years associated with the additional hydropower capacity requirement.     

Determinants of adaptation practices to climate change by Chepang households in the rural Mid-Hills of Nepal

This study analyzes the factors influencing the adoption of various adaptation practices by a highly marginalized indigenous community in the remote rural Mid-Hills of Nepal. The analysis is based on a household survey conducted among 221 Chepang households selected randomly. A multivariate probit model was used to analyze five categories of adaptation choices against a set of socio-economic, institutional, infrastructural, and perception variables. Perception of rainfall changes, size of landholding, status of land tenure, distance to motor road, access to productive credit, information, extension services, and skill development trainings are all influential to enable households to deviate away from traditional coping strategies and adopt suitable practices to adapt to climate vagaries. Policies and development activities should be geared to address these determinants in order to facilitate adaptation.     

Factors affecting the adoption of multiple climate‐smart agricultural practices in the Indo‐Gangetic Plains of India

Climate change poses a major threat to agricultural production and food security in India, and climate‐smart agriculture (CSA) is crucial in addressing the potential impacts. Using survey data from 1,267 farm households in 25 villages from Bihar and Haryana in the Indo‐Gangetic Plains, this study analyzes the factors that determine the probability and level of adoption of multiple CSA practices, including seeds of stress‐tolerant varieties, minimum tillage, laser land leveling, site‐specific nutrient management and crop diversification. We applied a multivariate probit model for the simultaneous multiple adoption decisions, and ordered probit models for assessing the factors affecting the level of adoption. The adoption of the various CSA practices is interrelated, whereas several factors, including household characteristics, plot characteristics, market access and major climate risks are found to affect the probability and level of CSA adoption. Climate‐smart agriculture (CSA) adoption and its intensity also vary significantly between eastern Bihar, which is relatively poor and densely populated, and north‐western Haryana. Engaging multiple stakeholders such as farmers, agricultural institutions, agricultural service providers and concerned government departments at the local level is crucial for the large‐scale uptake of CSA. The study, therefore, calls for agricultural policy reforms so that most of the issues related to the uptake of CSA can be adequately addressed.