Research Journal of Chemistry and Environment

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Research Journal of Chemistry and Environment

Single Drop Microextraction-Gas Chromatography Mass Spectrometrometry: A Method for Determination of Organophosphorus Pesticides in Fruit Juices and Water

Rahul, C. B. Majumder and P. Roy

In this study, a method for the determination of organophosphorus pesticides (OPPs) (dichlorvos, phorate, parathion, fenitrothion, malathion, and quinalphos) in orange juice and water was has been examined. Single-drop microextraction (SDME) parameters, such as organic solvent, drop volume, agitation rate, extraction time and salt concentration were optimized through analysis of OPPs in fortified water. The orange juice was simply centrifuged and diluted with water, extracted by SDME and analyzed by gas chromatography (GC) equipped with a mass-spectrometery. Fortification tests were conducted for concentrations between 10 and 50 µg/L; mean relative recoveries for each pesticide were all above 72.9% and below 109.4%. Limits of detection of the method for orange juice were below 5 µg/L for all target pesticides and 0.049 to 0.81 µg/L for water. The repeatability of the proposed method, expressed as relative standard deviation varied between 4.2 and 11.6% (n = 5). The proposed method enables a rapid and simple determination of organophosphorus pesticides in water and fruit juice with minimal solvent consumption and a higher concentration capability.

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A Generalized Mathematical Model for the Anaerobic Biodegradation Process

S.Y. Bodkhe

In this study a fixed film fixed bed anaerobic reactor was used for the treatment of domestic wastewater with higher concentration of particulate suspended solids. Complexity in ecology of anaerobic treatment systems due to presence of variety of microbial populations led to incorrect prediction of the performance of the process. Development of a generalised mathematical model for the anaerobic reactor system has been envisaged in this study after comparative analysis of four most widely used mathematical models. It has been revealed that a single generalised kinetic equation: ds/dt = - KHA. S. XA can describe the anaerobic biodegradation process better than the other existing models. The values of parameters, A and KHA derived in this study were found to be 0.423 and 3.68 and the modified generalized kinetic equation for the anaerobic biodegradation process was obtained to be: dS/Sdt = -3.68*S*X0.423

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Studies on Spiroheterocycles Part-IV: X-Ray Crystal Structure of 2, 4, 7, 11-Tetraphenyl-3-thioxo-2, 4-diaza-spiro [5, 5] undecane-1, 5, 9-triones

Rajani Kanta Behera, Ajay Kumar Behera, Rosy Pradhan, Anita Pati and Manabendra Patra

Michael addition of dibenzalacetone with 1,3- diphenyl thiobarbituric acid affords the spiro compound 2, 4, 7, 11-Tetraphenyl- 3 -thioxo-2,4-diaza-spiro[5,5] undecane-1, 5, 9-triones. The crystal structure of the above compound has been determined by X-ray method. The compound is monoclinic, P21/ C with cell parameter a = 17.131 (2) A0, b = 9.695 (12) A0, c = 16.230 (2) A0, b = 91.376 (3) A0, n = 2.694 (6) A0, z = 4, DC = 1.308mg/m3, Fooo = 1112, T = 298 oK.

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Chemoselective Tetrahydropyranylation of Alcohols and Phenols on Functionalized SiO2 Catalyst

Manoj B. Gawande, R.V. Jayaram and Sunil R. Murkute

A simple, efficient and highly chemoselective method for the tetra-hydropyranylation of alcohols and phenols has been developed by their reaction with 3,4-dihydro-2H-pyran at room temperature (30 0 C) in the presence of catalytic amount of silica sulphate, as a reusable catalyst.

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Activated Carbon Adsorption of Anionic and Cationic Dyes from Aqueous Solutions

Diksha Aggarwal and Meenakshi Goyal

The adsorptive removal of a cationic (Rhodamine B) and anionic (metanil yellow) dyes from aqueous solutions has been studied using four activated carbons prepared from different source raw material and using different processing procedures. The activated carbon surface was modified by oxidation with nitric acid and oxygen gas and by degassing at different temperatures. The adsorption of the anionic dye decreased while that of the cationic dye increased on oxidation. However, the decrease or the increase in adsorption was much larger on oxidation with nitric acid than with oxygen gas. The degassing of the oxidized carbons showed an opposite trend. While the adsorption of the anionic dye decreased with increasing temperature of degassing, that of the cationic dye decreased on degassing. The results have been explained in terms of the chemical nature of the dye and the carbon surface charge. The presence of acidic oxygen groups renders the carbon surface negatively charged which produces repulsive or attractive electrostatic interactions between the carbon surface and the anions or the cations of the dye molecule.

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Comparison of Structure and Property of AZT and its Analogue HIV, Inhibitors and DFT Calculations: Study of Anti-AIDS

Majid Monajjemi and A. Abedi

Analogues of nucleosides that lack the 3'-hydroxyl group are being studied extensively as potential therapeutic agents for the treatment of acquired immunodeficiency syndrome (AIDS). We analysed the several physico chemical properties like solubility (by VCL), lipophilicity (by milinspiration), dipole and quadrupole moments (by Density Functional Theory) for 7 AZT analogs and compared these parameters with inhibition assays of them. It was found that cytotoxicity of these drugs is related with their lipophilicity inversely. It is shown that AZT and its analogues are similar in structure and properties.

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Ambient Concentrations of Benzene and Other VOCs at Typical Industrial Sites in Kuwait and their Cancer Risk Assessment

S. M. AL-Salem and W. S. Bouhamrah

Benzene levels in ambient air have been monitored for a period of two years in different sites of an industrial area in Kuwait. Health Risk Assessment, HRA of benzene has been evaluated. An analysis of the sources contributing to the background concentrations of benzene as a carcinogen was done. Standards both locally (Kuwait Environment Public Authority, KUEPA) and internationally (United States Environmental protection Agency, USEPA) were taken into consideration. Ambient guidelines and exposure limits were considered in this study to detect the deviations from given standards. Suggested plans and strategies are designed to meet the general requirements of potential health related issues.

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Excess Molar Volumes and Deviations in Viscosity of Binary Mixtures of Propyl Acetate with Butan-1-ol and Pentan-1-ol

Bhatu S. Desale, Mehdi Hasan and Hari. A. Patil

Densities and viscosities of binary mixtures of propyl acetate with butan-1-ol and pentan-1-ol have been measured over the entire range of composition at 298.15, 303.15, 308.15 and 313.15 K and at atmospheric pressure. From the experimental value of density and viscosity, the excess molar volume (VE) and deviation in viscosity (Dh) have been calculated. The excess molar volumes and deviations in viscosity are fitted to Redlich–Kister polynominal equation.

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New Approach to Modeling in Micellar Liquid Chromatography

Alexander P. Boichenko, Lidia P. Loginova, Anna L. Iwashchenko and Artem U. Kulikov

Separation of four 4-hydroxybenzoic acid esters and seven polyaromatic hydrocarbons has been performed by micellar liquid chromatography to study the variability of retention factor. Full two factor experimental design with three levels for each factor has been used to study the dependence of retention factor variance on mobile phase composition (sodium dodecylsulfate, 1-butanol) for four 4-hydroxybenzoic acid esters. The experimentally observed heteroscedasticy and perturbations after linearization were taken into account in modeling by using sensitivity weights obtained on the basis of errors propagation law. Modeling of retention by non-weighted and weighted least squares method has been performed by three retention equations. The proposed dependence between log k and log cS, log cR (cS – sodium dodecylsulfate concentration, cR – concentration of 1-butanol) provides an adequate fitting. The high correlation has been obtained for dependence between logarithm of retention factor and log Po/w for polyaromatic hydrocarbons.

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Diffusion of Sodium and Iron in Yttrium and Magnesium Containing Oxynitride Glasses - A Comparative and Mechanistic Study

Tanmay Das

Diffusion of sodium and iron in Y-Si-Al-O-N and Mg-Si-Al-O-N glasses having composition similar to the ones present at the grain boundary of dense silicon nitride ceramics was done in the temperature range 690 to 920oC. The concen-tration profiles of the radiotracers 22Na and 59Fe were determined from residual activity measure-ments. In order to get the isolated effect of N on diffusion behaviour, the atomic ratio Al:Y(Mg):Si in all the glasses was maintained constant at 1:1.36:2.32.In the present temperature range of study highest value of diffusion coefficient occurred for the diffusion of Na in glass of 0 at% N in the Mg-system at 850oC which was 1.74x10-11 cm2/s while the lowest value occurred for the diffusion of Fe in the Y-system glass with 8 at% N at 800oC and was 1.22 x 10-15 cm2/s. The trend in the change of different diffusion parameters was explained from a mechanistic outlook considering both the modes of diffusion – the interstitial and vacancy. Findings of the Mossbauer and EPR spectroscopies were corroborated in terms of the possible occupancy of Fe in such glasses.

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Adsorption of Basic Brown 4 (Basic Dye) Using a Low Cost Activated Carbon Prepared from Agricultural Solid Waste: Turmeric Industrial Waste

S. Karthikeyan, M. Jambulingam, P. Sivakumar and N. Renugadevi

The adsorption of Basic Brown 4 (Basic Dye) on Turmeric Industrial waste carbon was investigated to assess the possible use of this adsorbent for the processing of dye industry waste water. The influence of various factors such as initial concentration, agitation time and temperature on the adsorption capacity has been studied. The percentage removal of dye is observed to decrease with the increase in initial concentration of dye. With increase in temperature the adsorption of dye increases indicating endothermic nature of the reaction. Adsorption isothermal data could be interpreted by the Langmuir and Freundlich equations. Kinetic data has been studied using Elovich and pseudo-second order equations for understanding the reaction mechanism. Thermo-dynamic parameters such as DG, DH and DS for the adsorption process were calculated.

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Kinetics and Mechanism of Complexation of Cr(III) with Phenoxyacetic Acid Herbicides in Plants and Environment: Improbability of Chelation Hypothesis

S.S.S. Kushwaha and Sandhya Gupta

The interaction of Cr(III) with phenoxyacetic acid (PAA). 2-chlorophenoxyacetic acid (2-CPA). 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) has been studied in the pH range 3-4.5. The stoichiometric composition of the complexes has been identified to be 1:1. The variation of pseudo-first order rate constants with pH, ionic strength temperature and ligand concentration supported a mechanism based on ion-pair formation. An associative interchange mechanism has been suggested for the reactions irrespective of a ligand involved. The activation parameters calculated by using Eyring equation have indicated that the anation of hexaquo-chromium (III) with a ligand is faster than the exchange of water indicating associative interchange mechanism of metal complexation followed by ion-pair formation. Also, the rate and equilibrium data for both biologically active and inactive phenoxyacetic acids are of comparable magnitudes, thereby ruling out the possibility of chelation as a possible mode of action of these herbicides. Also, the complexometric estimation of average or seasonal losses of herbicides for any desired period may be predicted fairly well in view of complex nature of environmental conditions to prevent environmental pollution.

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Abatement of TSS Level from MBF Clarifier Wastewater using different Flocculants - A Case Study

Ashim Kumar Bhattacharya and Sailendra Nath Mandal

In consonance with more stringent environmental regulations, environmentally sound waste management and disposal are becoming increasingly more important in all aquaculture operations. One of the primary water quality parameters of concern is enhanced concentration of suspended solids in the discharged effluent. For example, Environmental Protection Agency initially considered the establishment of numerical limitations for only one single pollutant i.e., to explore total suspended solids (TSS). The objective of this study was abatement of TSS from wastewater, which was collected from inlet to Mini Blast Furnace (MBF) clarifier of a Steel Plant near Jamshedpur using several commercially available flocculants. Experimental investigation on reduction of TSS level in wastewater sample was carried out utilizing flocculants having different ionicity using a jar testing apparatus. Study revealed that anionic flocculants having medium ionicity (30 % anionic charge) perform well compare to cationic and non-ionic flocculants. Further, anionic latex polymers were found to be much more effective than the dry polymer having the same ionicity.

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Phytochemical Constituents from Desmodium Tiliaefolium (G. Don.)

R. N. Yadava and Abha Verma

A novel flavone glycoside m.p. 270-272oC, m.f. C34H42O20, [M]+ 770 (FABMS) was isolated from the acetone soluble fraction of the stem of the Desmodium tiliaefolium (G. Don). It’s structure was characterized as 5,7,4'-trihydroxy 3, 8-dimethoxy flavone 5-O-a-L-rhamnopyranosyl-7-O-b-D-galactopyranosyl (1®4) O-b-D-xylopyranoside by various chemical degrada-tions and spectral analysis.

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Synthesis, Antibacterial and Antifungal Activities of Mannich Bases of 8 - hydroxyquinoline Derivatives

M.I. Fazal Mohamed, G. Krishnamoorthy and B.R. Venkatraman

Mannich bases exhibit several pharmaco-logical properties. Many substituted aminomethyl derivatives of unsaturated ketones are known to possess antitumour and antifungal activities. 8-hydroxyquinoline acts as an intermediate in the manufacture of more complex compounds of medicinal value. In the present study, it has been aimed to achieve better antimicrobial profile at lower doses by preparing mannich bases of 8- hydro-xyquinoline with the secondary amino groups viz., phthalimide, isatin, 5–fluoroisatin, 5-chloroisatin, diphenylamine and succinimide. These compounds were synthesized by condensation with form-aldehyde and screened for their antimicrobial activity. Mannich base derivatives were screened for their antifungal activity against candida albicans using ketacona-zole as the standard drug. It was found that all the derivatives synthesized were found to be more active than ketaconazole against candida albicans. The results of antimicrobial activity of the derivatives were found to be comparably active with the standard (ciprofloxacin) against four pathogenic bacteria namely Staphylococcus aureus, Staphylo-coccus albus, Pseudomonas aeruginosa and Escherichia coli by disc diffusion method.

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Mini Review-Green Cluster: Polyethylene Glycol (PEG): A Green Solvent in Organic Synthesis

Zhan-Hui Zhang

PEG serves as a green and reusable solvent for various organic reactions. The simple separation of homogeneous catalysts could be realized through monophasic catalysis coupled with biphasic separation.

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Review Article: Biomorphic Ceramics: Synthesis.

C. Bosch Ojeda and F. Sánchez Rojas

Ceramic and glasses are some of the more recent and more resistant materials of engineering to the environmental conditions. They belong to advanced materials more than they are being developed for the aerospace and electronic industry. In this work a bibliographical revision is made on the preparation of ceramic materials with biomorphic microstructures. In general, biological coal preforms are obtained (CB-templates) from wood with different structures by pyrolysis from high temperature (800 to 1800 ºC), that they are used as templates for the infiltration, mainly, with Si gaseous or liquid forming ceramics with SiC and SiSiC.

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