Performance enhancement of solar photovoltaic system for roof top garden

Environmental Science and Pollution Research - The photovoltaic (PV) for irrigation system is an emerging technology to harness the solar energy. The performance of the PV modules depends on the...     

Spatio-temporal assessment of ambient air quality,their health effects and improvement during COVID-19 lockdown in one of the most polluted cities of India

Environmental Science and Pollution Research - The present work aims to investigate seasonal variations in air pollution levels in Lucknow and assess the ambient air quality of the city together...     

Removal of chromate ions from leachate-contaminated groundwater samples of Khan Chandpur,India, using chitin modified iron-enriched hydroxyapatite nanocomposite

Environmental Science and Pollution Research - Chromite ore processing residues (COPR) are real environmental threats, leading to CrO42-, i.e., Cr (VI) leaching into groundwater. It is of serious...     

Degradation of biopolymeric pigments in distillery spentwash by electrocoagulation using copper anodes: statistical and canonical analysis

The electrocoagulation studies of distillery spentwash using copper anodes were utilized to demonstrate the usefulness of Box–Behnken experimental design of response surface analysis to derive a statistical model and the optimum parameters for color removal. The current intensity (1.5 A), dilution (10%) and time of electrolysis (5 h) had been found to be the optimum conditions for maximum 77.11% color removal. The actual color removal at optimized conditions was found to be 78.26%, which is to the predicted response using response surface methodology. The energy consumption and current efficiency were determined from reduction in chemical oxygen demand.     

Physiological,biochemical and growth responses of Azolla pinnata to chlorpyrifos and cypermethrin pesticides exposure: a comparative study

Cypermethrin and chlorpyrifos pesticide- (5, 15 and 30 ppm) induced effects on growth, metabolic and antioxidative behaviour of Azolla pinnata were analysed after 96 h of treatment. Growth of A. pinnata was increased by 72–76% over the initial mass under control condition. Further, the growth was decreased by 26 and 30% following treatment with 5 ppm of cypermethrin and chlorpyrifos, respectively, compared to control. Whereas, 30 ppm of pesticide treatment caused substantial decrease in biomass accumulation, even less than the initial mass. The Chlorophyll a content was declined at higher concentrations of chlorpyrifos, while carotenoids content increased significantly in the presence of both the pesticides. Photosynthetic rate showed declining trend with rising concentration of pesticides, while an increasing trend was noticed in the case of respiratory O₂ consumption. The oxidative biomarkers malondialdehyde, superoxide radicals and hydrogen peroxide increased with increasing concentration of both the pesticides. The activity of enzymatic antioxidants enzyme superoxide dismutase, glutathione-S-transferase and ascorbate peroxidase (APX) was enhanced with increasing concentrations of both the pesticides; however, a declining trend was noticed in the case of APX at 30 ppm chlorpyrifos treatment. The study concludes that chlorpyrifos appeared to be more toxic than cypermethrin; however, both the pesticides significantly reduced the growth performance.     

Metabolic responses of Azolla pinnata to cadmium stress: photosynthesis,antioxidative system and phytoremediation

This present study deals with the growth, photosynthesis, oxidative stress and phytoremediation character of Azolla pinnata L. exposed to different levels (0.05, 0.1, 0.5, 1.0, 1.5 and 2.0 mg·L^?1) of cadmium (Cd). Significant accumulation of Cd in Azolla fronds was noticed after 24 and 96 h of exposure and the accumulation rate was dose and time dependent. Growth of A. pinnata increased significantly after both exposure times with and without metal. At lower Cd doses (0.05 and 0.1 mg·L^?1), growth and photosynthesis of A. pinnata showed a marginal increase over the respective control, however, at higher Cd doses (0.5, 1.0, 1.5 and 2.0 mg·L^?1), a decreasing trend was noticed. At lower doses, Azolla fronds could counterbalance the negative effect of enhanced levels of superoxide radicals (SOR) and hydrogen peroxide (H₂O₂) through the greater activity of antioxidative enzymes. The decaresing trends in catalase and peroxidase activity at higher Cd doses suggest that Azolla fronds were not able to mitigate the negative effects of H₂O₂, hence an increase in malondialdehyde content was noticed. The study concludes that up to 0.1 ,mg·L^?1 Cd, A. pinnata can flourish and be used as biofertiliser and for phytoremedial purposes in Cd-contaminated fields; beyond this concentration poor growth may restrict its application.     

Chelating resin immobilized sawdust packed chromatographic column: Application to separation and preconcentration of lead ion

Naturally abundant rubber sawdust has been utilized as a stationary support, which after immobilization with a chelating polyelectrolyte (xylenol orange as counterion) gets converted into a suitable column packing material for isolation and enrichment of trace level target analyte, accurately detectable by the technique of differential pulse anodic stripping voltammetry. The sorbent is robust and re-usable in column-chromatography without showing any leaching and interference complications. Its unique lead ion selectivity from multielemental complex matrices (synthetic water sample, blood serum) at optimized column conditions (pH 2.5 and flow rate 0.5?mL?min^?1) mitigates the usual problems of intermetallic and readsorption effects. Effects of flow rate, pH, equilibration time, and other variables are reported. The system has advantageous feature to be used in a single-column ion chromatography with satisfactory performance. A modest attempt has been made to determine lead fractions in human blood serum samples on the bases of selective retention of ionic and labile fractions on complexing resin.     

Performance and validation of a coupled parallel ADCIRC–SWAN model for THANE cyclone in the Bay of Bengal

An accurate prediction of near-shore sea-state is imperative during extreme events such as cyclones required in an operational centre. The mutual interaction between physical processes such as tides, waves and currents determine the physical environment for any coastal region, and hence the need of a parallelized coupled wave and hydrodynamic model. The present study is an application of various state-of-art models such as WRF, WAM, SWAN and ADCIRC used to couple and simulate a severe cyclonic storm Thane that developed in the Bay of Bengal during December 2011. The coupled model (ADCIRC–SWAN) was run in a parallel mode on a flexible unstructured mesh. Thane had its landfall on 30 December, 2011 between Cuddalore and Pondicherry where in-situ observations were available to validate model performance. Comprehensive experiment on the impact of meteorological forcing parameters with two forecasted tracks derived from WRF model, and JTWC best track on the overall performance of coupled model was assessed. Further an extensive validation experiment was performed for significant wave heights and surface currents during Thane event. The significant wave heights measured along satellite tracks by three satellites viz; ENVISAT, JASON-1 and JASON-2, as well in-situ near-shore buoy observation off Pondicherry was used for comparison with model results. In addition, qualitative validation was performed for model computed currents with HF Radar Observation off Cuddalore during Thane event. The importance of WRF atmospheric model during cyclones and its robustness in the coupled model performance is highlighted. This study signifies the importance of coupled parallel ADCIRC–SWAN model for operational needs during extreme events in the North Indian Ocean.     

A dynamic model for costing disaster mitigation policies

The optimal level of investment in mitigation strategies is usually difficult to ascertain in the context of disaster planning. This research develops a model to provide such direction by relying on cost of quality literature. This paper begins by introducing a static approach inspired by Joseph M. Juran's cost of quality management model (Juran, 1951) to demonstrate the non‐linear trade‐offs in disaster management expenditure. Next it presents a dynamic model that includes the impact of dynamic interactions of the changing level of risk, the cost of living, and the learning/investments that may alter over time. It illustrates that there is an optimal point that minimises the total cost of disaster management, and that this optimal point moves as governments learn from experience or as states get richer. It is hoped that the propositions contained herein will help policymakers to plan, evaluate, and justify voluntary disaster mitigation expenditures.