This study presents emissions of different pollutants from transport sector in Delhi. Results show that emissions of pollutants have increased during 2001-2009 as follows: CO2, 4395-6423; CH4, 1.03-3.32; N2O, 0.04-0.05; CO, 238-329; NOx, 44-64; and NMVOC, 44-60 Gg. However, CO2 emissions per unit of vehicle types for gasoline driven vehicles show a decrease as follows: two wheelers, 2.7; and cars, 4.3%; while in case of diesel driven vehicles, this reduction is 1.6%, indicating impact of better vehicle technologies introduced.

This review presents tropospheric ozone (O3), an air pollutant affecting agriculture by reducing crop yield and deteriorating quality of produce. O3 enters leaves through stomata and diffuses within the apoplast, producing many oxidizing compounds and affecting various physiological and biochemical processes, crop growth and yield. O3 affects above and below ground carbon allocation and its dynamics, N cycling, microbial content and emission of greenhouse gases (GHG) from soil.

This study proposes a comprehensive noise abatement programme following the best practicable and economical option (BPEO) for implementation in metro city like Delhi for reducing annoyance and ill effects of traffic noise. It reviews potential applications of noise control barriers and vegetation for reducing road traffic noise and presents a design morphology and decision matrix using TOPSIS (Technique for order preference by similarity to ideal solution) approach for selection of appropriate sound barriers.

This study presents biogas production from fruit wastes at ambient temperature using anaerobic batch digester (500 ml). Co-digestion of fruit wastes were carried out with rice bran and cow dung. Biogas production from different samples was as follows: Sample A (fruit waste), 363; sample B (fruit waste, 75% + cow dung, 25%), 405; sample C (fruit waste, 75% + rice bran, 25%), 315; and sample D (fruit waste, 50% + rice bran, 25% + cow dung, 25%), 381 ml. From chromatographic studies, sample B has maximum methane content (80%) and sample C has maximum carbon-di-oxide content (50%).

This study presents various vegetable oils from edible and non-edible sources for preparation of biodiesel using KOH as catalyst and methanol as alcohol. Maximum biodiesel yield from all vegetable oils was obtained under following optimum conditions: reaction temp., 70°C; reaction time, 1 h; catalyst amount, 1% (by oil wt); and methanol to oil molar ratio, 6:1. Characteristics of biodiesel at optimum conditions were as per ASTM standards.

This review presents biological treatment methods for petroleum refinery wastewater, their applications, advantages and disadvantages. It covers refinery wastewater characteristics, different categories of biological treatment systems (suspended, attached and hybrid growths) and comparison between each system with conventional activated sludge process.

Reverse osmosis (RO) with polyamide membrane of spiral wound and precipitation with commercial sodium carbonate were studied to remove hazardous substances [chromium(III), sulfate, chloride and sodium] contained in a tanning wastewater. RO removed chromium(III) very efficiently (99.83%) and with lower but appreciable yields the other three constituents of liquid effluent. Major inconvenience of RO was fast decrease of permeate flux due to insufficient transmembrane pressure used. In turn, 99.71% of chromium(III) was separated with precipitation.

This study presents effect of injection timing on performance, combustion and emission characteristics of mahua biodiesel (Madhuca indica) and its blends with pure diesel on a 4 stroke tangentially vertical single cylinder (TV 1) direct injection diesel engine. At injection timing of 22° bTDC, blend B25 (25% mahua biodiesel and 75% pure diesel, by vol) gave optimum performance, which is very close to pure diesel. Thus B25 fuel can be effectively used in a diesel engine as an alternative fuel without any modification in the engine.

This study presents performance behaviors of a commercial diesel engine fueled with diesel and Jatropha based biodiesel (B100) at various loads (up to 100%) and compared using standard (conventional) and three new face profile designs (I, II & III) of piston rings. BTE of engine fueled with diesel increases 2-8% with new face profile design (III) of piston rings in comparison to standard (conventional) piston rings. BTE enhances 8-16% when engine is fueled with biodiesel using face profile design (III) on piston rings.

This study presents bioconversion of water hyacinth (Eichhornia crassipes) to bioethanol using two-sequential steps of acid hydrolysis (10% sulfuric acid) and yeast (Candida intermedia) fermentation. A maximum ethanol yield (coefficient, 0.21 g g-1; productivity, 0.010 g l-1h-1) was comparable to predicted value (0.23 g g-1) obtained by CCD (Central Composite Design). Two colorimetric methods (phloroglucinol and dichromate assays) were used for determination of xylose and ethanol using UV-Vis spectrophotometer.