ELECTROCHEMICAL DETERMINATION OF NITRO EXPLOSIVE (HNS) USING GLASSY CARBON ELECTRODE

A glassy carbon electrode (GC) exhibited an attractive performance for the detection and determination of a nitro compound like 1,2- Bis(2,4,6-trinitrophenyl)ethylene (HNS). Cyclic voltammetry, differential pulse and square wave voltammetry were used in a combined way to identify the electrochemical characteristics and to optimize the conditions for detection. For calibrating and estimating HNS, square- wave voltammetry was mainly used. The HNS shows a well-defined peak at in the dimethy sulfoxide (DMSO) containing Tetrabutyl Ammonium Bromide (TBABr) medium. The existence of peak at -0.10 V showed good peak and high current response

Methane emission potential of open dumps in Chennai: a case study

Monitoring of atmospheric levels of methane and other Greenhouse Gases (GHGs) holds great promise for the mitigation of global warming resulting from increasing radioactive trapping by atmospheric gases. Since, the direct measurements of landfill methane emission found to be difficult, the methane emission potential of the open dumps in Chennai has been estimated using first-order decay models such as TNO, LandGEM and zero-order model (EPER model, Germany). The resulted methane emission was around 33 × 106 m3, 36 × 106 m3 and 52 × 104 m3 based on the TNO, LandGEM and zero-order models, respectively. The results concluded that the methane emission from the Chennai dumps contributed to 0.13% of the overall global landfill methane emission and 1.3% of Indian landfill methane emissions within the years between 1986 and 2003

Heavy metal fractionation and leachability studies on fresh and partially decomposed municipal solid waste

Leaching of Cd, Cr, Cu, Pb, Ni, and Zn from fresh and partially decomposed municipal solid wastes using acid digestion (AD), multiple extraction procedure (MEP), toxicity characteristic leaching procedure (TCLP), and equilibrium leach test (ELT) was carried out. Sequential extraction studies were conducted to evaluate the mobility of heavy metal ions by fractionating into exchangeable, acid extractable, oxidizable, reducible, and residual fractions. The extraction efficiency of the tests decreased in the following order: AD > MEP > TCLP > ELT. Less than 45 of the metal contents were in bioavailable (exchangeable and acid extractable) form, except Ni. Total and TCLP extractable metal contents were within the limits prescribed for USEPA compost and TCLP regulating limits, respectively