Abstract: The relaxed eddy accumulation (REA) method was applied to estimate dry deposition fluxes and velocities of SO₄^2- and NO₃^- above a tropical forest. The monthly measured concentration of NO₃^- was found to be greater than that of SO₄^2-. The average dry deposition flux of NO₃^- was found to be greater than that of SO₄². The average deposition velocities of sulfate were evaluated to be 0.30 cm s^-1 during the day and 0.22 cm s^-1 at night, while the highest deposition velocities of nitrate were 0.93 cm s^-1 during the day and 0.54 cm s^-1 at night. The deposition velocities of aerosols (SO₄^2- and NO₃^-), calculated by using the resistance model, were found to be 0.49 cm s^-1 during the day and 0.29 cm s^-1 at night.

Abstract: Sugar industry plays an important role in the economy of India by way of farming and creation of employment. The by-products of sugar mills are also used as raw materials in different industry. However sugar mill have a great environmental impact upon the surrounding environment. The change of water chemistry is the main associated environmental impact of discharging sugar mill’s effluent on an open water body. The effluents are causing odor nuisance during decomposition and disturbed the plant, human and animal life. Due this an economical treatment has been introduced that is known to be electrochemical process. To treat the sugar industry wastewater aluminium plate was used as electrode material. It has been shown that the removal efficiency of COD increased with the increasing applied current density, increasing wastewater flow rate and polyelectrolyte addition. The results indicate that electrocoagulation is very efficient and able to achieve 84.2% COD removal and over 99% color removal in 90 min at 40 mA/cm² and wastewater flow rate of 1000ml/min.

Abstract: The levels of gaseous pollutants; carbon monoxide (CO), hydrogen sulphide (H₂S), and particulate matter (PM) were determined using Electrochemical Sensors and Infra-red based particulometer. The areas under study were some busy roads in Jos, Nigeria including; Ahmadu Bello way, Bauchi road, Tomato market, and some junctions/ terminals; University of Jos gate, Farin Gada and Gada biu. The aim was to assess the extent of vehicular emission in the immediate environment. The result showed that the concentration 0f CO obtained ranged from 6 to 110ppm. The range of H₂S obtained was 1.0 to 3.6ppm, while particulate matter concentrations was in the range of 0.1 to 0.6 mg/m³. The peak CO concentrations was higher than the maximum tolerable limit of 50ppm with the possible consequences of causing toxicity to man. The particulate matter and H₂S levels are moderate compared to health standards but present an interesting trend for researchers and town planners to observe.

Abstract: A framework budget of ambient atmospheric gases and Particulate Matter are pooled over six stations in the metropolis of Kochi, Kerala, India, during the summer and winter seasons of 2010 and 2011. In order to assess the air quality in the coastal and industrial location, six topographically prominent and distinct areas are selected. The gases like sulphur dioxide, nitrogen dioxide and ammonia are selected owing to its importance on human health. Besides, particulate matter is monitored in order to quantify the trace metal present, which causes serious respiratory and cardiac problems. Elevated concentrations are observed in winter for all the parameters monitored compared to summer, which provides an insight in to the circulation of gases and particulate matter along the unlike seasons. The winter season with more stable atmospheric pattern tend to cumulate the pollutants rather than dispersing it due to temperature gradient. Industrial sites show prominent levels of sulphur dioxide and ammonia. Considerable increase in nitrogen dioxide unravels the folded increase in vehicular motors. The particulate matter study for selected trace metals untie the concentration of iron, lead, copper and zinc to be augmented in winter. Statistical methodologies are applied to assess the relationship between the seasons.

Abstract: The practicability and applicability of the most classical models for a particular location depends largely on validation against actual measurements, hence the parameterizations of the sub-grid scale process play an important role at Atmospheric Boundary Layer (ABL) for appropriate representation of model outputs. This study presents a simple parameterization for some radiative fluxes and pollution parameters at ABL in a tropical city Delhi. The characteristic of the parameterization is that the experimental data sets obtained during the experimental field campaigns are fit into a linear regression relation with the parameterized values according to the different land-use pattern and coefficients are presented, that are in comparable with earlier studies.