A kinetic study of reaction between benzaldehyde, malononitrile and 4-hydroxycoumarin compounds has been established spectrally in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) and sodium acetate as a catalyst. Based on the experiment data, reaction followed second order rate law. The rate law that deduced from the mechanism was compatible with the observed rate law. The results showed that the first step of the reaction mechanism was a rate-determining step. Experimental effects of catalysts, solvent, concentration and functional group (structural effect) on the reaction rate provided useful information regarding the mechanism of reaction.
The Corrosion inhibitive behavior of Zinc complex of 1-(8-hydroxy quinolin-2yl-methyl) thiourea (Zn-HTF) on mild steel immersed in an aqueous solution containing 60 ppm Cl- has been evaluated by using mass loss method. The corrosion inhibition efficiency shows 80% by 50 ppm of Zn-HTF. The corrosion inhibition was observed due to the formation of more stable and compact protective film on the mild steel surface. Polarization study and Electrochemical Impedance spectra were applied to analyze the effect of the inhibitor on the corrosion of mild steel. Fourier transform infrared & UV-Visible spectroscopy was used to characterize the surface film. Iron-inhibitor complex that totally covered the mild steel surface was identified by fluorescence spectra. The morphology of inhibited and uninhibited mild steel was analyzed by scanning electron microscope (SEM) and energy dispersive analysis of X-rays (EDAX). Zn-HTF has the ability to prevent the growth of certain microorganisms.
This work focused on the conversion of Jatropha carcus (JC) to activated biochar (AC). JC seed shells were carbonised at 500oC producing a char yield of 90%. The char was then activated by sulfonation. The activated carbon produced was characterized in terms of pH, ash content, moisture content and adsorption capacity. The internal surface area of the sample was determined using iodine number test and was found to be 431 mg/g at 500°C with 9.32% ash content, 2% moisture content, and a pH of 5.80. The production of AC from JC involved soaking, drying, crushing, sieving, carbonisation, sulphonation, water washing and acid recovery and lasting drying and storage. A preliminary cost estimation of the suggested process was presented for a plant which can process 2500 kg/day of JS to produce 600 kg/day of AC. An economic analysis was done and proved the project to be viable as it has a return on investment of 24% with a payback period of 4.2 years at 75% plant utilization for a unit cost of $2.80 per kg.
Toxicity and reactivity of nitro polycyclics have been correlated with their molecular structure and electronic properties, in particular with the nitro substituent orientation. Experimental data are scarce for mononitro derivatives of benzo[a]pyrene (BaP) and benzo[e]pyrene (BeP), so density functional B3LYP/6-311++G(d,p) calculations have been performed on all of the isomers of nitro-BaP and nitro-BeP in their singlet and triplet states. The most stable configurations are planar ones in which NO2 interacts with the aromatic π-electron system, although the majority of structures are non-planar. Nitro substitution in the bay region of both BaP and BeP results in two stable singlet structures with very different geometries; the higher energy states show a strong O–C interaction that induces sp3 hybridization in the aromatic carbon atom. The calculated IR spectra display differences between planar and non-planar structures that can be used to predict the nitro group orientation and thereby the potential toxicity of each isomer.
The present investigation is carried out to analyse the ambient air in Puducherry city and determine the air quality. This investigation represented the assessment of ambient air quality with respect to SPM, Oxides of Nitrogen (NOx) and Sulphur Dioxide (SO2) for the year 2009 at six different sites. The Air Quality Index were calculated using IND-AQI procedure. It has been observed that the calculated Air Quality Index values for SO2 and NOx fall under ‘good’ and ‘good-to-moderate’ categories. The calculated Air Quality Index value of SPM for all areas is more than the prescribed standards given by the Central Pollution Control Board, New Delhi, India. The ambient air quality survey was carried out at 6 monitoring stations with respect to SPM, SO2 and NOx. The pollutant concentrations were used to calculate the Air Quality Index. This study reports the analysis of the ambient air in Delhi city employing air quality index. Thus, it is observed that SPM is a critical pollutant at these three sites in Puducherry. This study reports the analysis of the ambient air in Puducherry city employing air quality index. The 24-hourly average concentrations of four major criteria pollutants viz. SPM, SO2, NOX and CO for the year 2009 at six different locations in Puducherry city have been considered for this analysis. The overall Air Quality Index was found to fall under the category ‘poor’ owing to SPM. Thus, it is observed that SPM is a critical pollutant at these three sites in Puducherry.
Mineral systems were investigated to determine their effect on copper and zinc removal. This study was in relation to contaminated waters. Isotherms revealed metal removal by kaolinite, montmorillonite, goethite and their mixtures were dependent on particle size, pH, ionic strength, particle concentration and residence time. Kaolinite-montmorillonite and kaolinite-goethite demonstrated different sorption behavior from the single mineral systems. These mineral systems attenuated Cu and Zn removal over the range of pH (i.e. pH 4-8) investigated. Increased ionic strength (i.e.0.00 -0.1 mol/kg) and solid concentration (i.e. 0.002 to 0.01 kg/L), showed a complex response.
We used the DFT method to study the structure-antioxidant activity relationship of eugenol 1 and 6-bromoeugenol 2. First, we employed this method to predict the reliable orbital molecular energies. Then, we calculated the quantum chemical parameters: energy gap, chemical hardness, and Mullikan electronegativity. The results show that the presence of the bromine atom increases the antioxidant effect and the electrophilicity index increases with electronic effect. So, we can conclude that the antioxidant activity in 6-bromoeugenol 2 is generated by its structure. Our calculated results agree very well with the experimental data.
