Determination of Benzo[a]pyrene in Cigarette Smoke by Synchronous Fluorescence Scan

Digambara Patra

Identification and estimation of benzo[a]pyrene in the environment becomes important after the discovery of its association with carcinogenic and mutagenic properties. Benzo[a]pyrene is highly fluorescent and is present in cigarette smoke. A method has been developed based on synchronous fluorescence scan to identify and quantify benzo[a]pyrene in cigarette smoke. Unlike the conventional excitation and emission fluorescence scan, synchronous fluorescence scan gives a narrower and simpler spectrum, thus makes the analysis easy. The synchronous fluorescence spectra of benzo[a]pyrene in methanol, in six component PAHs mixture and in cigarette smoke have been compared. For quantification, the difference in fluorescence intensity of maximum and minimum obtained from the first derivative of synchronous fluorescence spectrum is measured with benzo[a]pyrene concentration. The calibration plot gives a good linearity (R = 0.9997) in the concentration range 5.7 x 10-9 M to 5 x 10-6 M. The amount of benzo[a]pyrene present in cigarette smoke has been estimated using first derivative synchronous fluorescence spectrum and is found to be 3.55 x 10 8M. The developed method is simple, selective and fast for determination of benzo[a]pyrene.

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Microwave Polarization Response of CO2 as a Function of Frequency and Temperature

Jai N. Dahiya and Jin K. Gong

This research paper involves the use of a microwave resonant cavity to study the dielectric response of CO2. The resonant cavity is used as a tool in a microwave spectro-meter operating in a certain range of frequencies. The main idea of this research investigation is to polarize the CO2 molecule using microwaves. More and more applications of microwave technology have been found in chemistry, pharmaceutical, plastic recycling, etc. Microwave technology is used to polarize a molecule of CO2. Carbon dioxide is a byproduct of many chemical reactions. The amount of carbon dioxide in the atmosphere has increased significantly in the last decade and that may contribute to the green house effect. Efforts have been made to reduce the emission of carbon dioxide. More important, scientific research of carbon dioxide is being carried out in utilizing the gas as a carbon source in the chemical industry

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Preparation and Characterization of Activated Carbon from Resak Wood (Vatica Hullettii):

Anuar K., Collin G. Joseph, Faujan B. H. Ahmad, Zulkarnain Z., Zobir M. Hussein and Halim A. Abdullah

The preparation of activated carbon from Resak wood, which is a tropical hardwood, was carried out in this study. The precursor was cut into 1.0-1.5 cm sizes and physically and chemically activated using carbon dioxide and zinc chloride at 500C. Characterizations and comparisons of some physical and chemical properties of the activated carbon were studied.

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Removal of Arsenic from Drinking Water using Activated Alumina

Pragya Singh, Tony Sarvinder Singh and K.K Pant

Arsenic is a commonly occurring toxic metal in natural systems and the root cause of many diseases and disorders. Present International drinking water standards set by Environmental Protection Agency with respect to arsenic is 0.05 ppm. In the present work an attempt to remove Arsenic (+5) by the use of an adsorbent, activated alumina was made. The Arsenic removal was dependent on water pH, initial Arsenic concentration and dose of adsorbent. Result of this work shows that activated alumina can be an effective adsorbent for the removal of Arsenic from water in the pH range of 5 to 7.

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Analytical Separation of Copper (II) and Cadmium (II) using Polymer Bound Imino Diacetic Acid

Shiv K. Gour, Pramila Jain, Sangeeta Loonker and P.N. Mathur

The preferential complexing tendency of different metal ions towards chelating agents anchored on a polymer has been used for separation of transition metals. The imino diacetic acid group was anchored on the polymeric cellulose back bone by successive coupling with trifunctional reagent cyanuric chloride in dioxane medium, at pH 7 and 8, respectively. Further, characterization of resin was done by means of IR spectra, nitrogen content and pH titration, the resin characteristics viz., bulk density, specific bulk volume, degree of substitution and ion exchange capacity were also determined. The effect of pH was considered in batch equilibrium study on the chelation of Fe (II), Co (II), Cu (II), Zn (II), Cd (II) and U (VI) metal ions. The metal analysis was accomplised by atomic absorption spectrophotometry. This polymer bound chelating agent was used to separate copper (II) and cadimium (II) in concentration range 1.0 to 0.1 m mol/L. The separation of a mixture of two components was quantitative using column chromatography.

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Polypyrrole Films : A Study on Electrochemical Preparation Using Various Alkylsulfonate Dopants and Chemical Characterization

Anuar Kassim, Abdul Halim Abdullah, Mohd. Zaki Abd. Rahman, Zulkarnain Zainal, Nita Salina Bte Abu Bakar and H. N. M. Ekramul Mahmud

An attempt has been made to prepare polypyrrole conducting polymer doped by several alkylsulfonates with varying carbon number such as methylsulfonate (C1), butylsulfonate (C4), octylsulfonate (C8) and dodecylsulfonate (C12) in aqueous medium by electrochemical method. The prepared polymer films were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray and elemental analysis. The conductivity of the prepared films was measured byfour-probe technique. The conductivity was found to increase with the increase of carbon number of alkylsulfonate dopant. The results of Fourier Transform Infrared (FTIR) and elemental analysis show that the alkylsulfonate dopants were incorporated to the polypyrrole structure. It can be seen from X-ray scattering for all the polymer films that the films are amorphous since all the films exhibited broad scattering maxima in the high-angle 2 θ ange from 20-30.

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Microbial Study for the Sequential Coagulation followed by Biological Treatment of an Alkaline Textile-Mill Effluent

D.K. Biswas, D.K. Markandey, B.K. Chaudhuri, S.D. Makhijani and Ashwajeet Garg

A treatability study was carried out by sequential coagulation followed by biological treatment for an alkaline textile-mill effluent. It was found that at the first stage of coagulation treatment almost all the heavy metals could be removed by usinglime, alum and ferric chloride. In addition to that, about 70% COD and 50% TDS were removed by this technique. About 25% of the residual TDS and 60 to 65% of the residual COD were further removed by biological treatment in the next stage, without any dilution. The removal of COD and TDS were somewhat improved by dilution with sewage water (1:1 ratio) and supplement of 0.5% DAP. However, the treated effluent still contained some residual COD, Color and TDS above the allowable discharge limits. But these parameteres were within allowable limits with pretreatment by sequential coagulation and dilution with 1:1(v/v) ratio with sewage water. About 10 potential microbial species out of total 20 isolates were characterized and identified. The most dominant species were found to be Bacillus followed by Aspergillus and Alkaligenes. Germination test of the treated effluent indicates that the treated effluent with suitable dilution may be used for irrigation purpose. For complete removal of COD, TDS and Color, it is recommended to provide some advanced physicochemical treatments like ozonation, membrane-filtration, etc. before or after the biological treatment.

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Selective Solvent Extraction and Spectrophotometric Determination of Palladium (II) with 2-arylthio-p-nitroacetophenone

P.T. Gojare, S.H. Gaikwad and M.A. Anuse

A simple, rapid and selective method for the extractive spectrophotometric determination of Palladium (II) is described. Palladium (II) is extracted with chloroform solution of 2-arylthio-p-nitro-acetophenone from 7 to 8 M acetic acid medium. The palladium (II)-2-arylthio-p-nitroacetophenone is max and molar absorptivities of the yellow coloured complex. The palladium (II) complex are 430 nm and 16121 mol1 cm1 respectively. Common anions and cations do not interfere in the determination of palladium (II). The difference in the absorbance between the blank determination and palladium (II) sample increases linearly in the concentration range 2.5-20 ppm at 7 M acetic acid. The overall process of extraction and determination takes about 15 minutes.

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Seasonal Variations of Phytopigments in the Northwestern Bay of Bengal

Abhijit Mitra, Kakoli Banerjee, Sudipta Pal1, B. Mahapatra, K.C. Halder, D.P. Bhattacharyya, K. L. Das, S. Majumdar and A. Choudhury

An attempt has been made to prepare polypyrrole conducting polymer doped by several alkylsulfonates with varying carbon number such as methylsulfonate (C1), butylsulfonate (C4), octylsulfonate (C8) and dodecylsulfonate (C12) in aqueous medium by electrochemical method. The prepared polymer films were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray and elemental analysis. The conductivity of the prepared films was measured byfour-probe technique. The conductivity was found to increase with the increase of carbon number of alkylsulfonate dopant. The results of Fourier Transform Infrared (FTIR) and elemental analysis show that the alkylsulfonate dopants were incorporated to the polypyrrole structure. It can be seen from X-ray scattering for all the polymer films that the films are amorphous since all the films exhibited broad scattering maxima in the high-angle 2 θ range from 20-30

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Destruction of Aflatoxin and Fungi Decontamination Study by Ultraviolet and Microwave Irradiation

H. Ghafourian, R. Dabbagh, F. Kafaei1, J.B. Raoof, A. Sadighzadeh

Microwave and ultraviolet irradiation are used for rapid sterilization in medicine and food industries, for example, sterilization of materials which have been contaminated with Aspergillus flavus and A. parasiticus which produce aflatoxin. Microwave exposure induces a morphological modification of the cells. There was a significant reduction in fungal growth compared to those which where controlled due to increased microwave exposures times. A microwave exposure time of 4 and 6 minutes is effective and exposure of 10 minutes provides a very effective rapid sterilization of two types of fungi A. flavus and A. parasiticus. UV irradiation in 254 nm wave length was also used for inactivation of mentioned fungi and destruction of aflatoxin. We found 10 cm distance and W.s/cm2 dose for practical conditions 360 sec exposure time or 108000 which that of pistachio fungi would have been inactivated. For aflatoxin destruction, experiments has been carried out first for opitimization of radiation time. For this manner 52 ppb aflatoxins(B1, B2, G1) were added to 25 g pistachio and samples were exposed to ultraviolet radiation for 1 to 10 hours. Toxins were extracted by 80% methanol and concentration of toxins was determined by HPLC by means of nanogram. Infra-red spectroscopy investigations showed that ultraviolet irradiation has broken lactone and furan rings in 8 hours.

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Paraffin Composite Copper Hexacyanoferrate Modified Electrode for Catalytic Oxidation and Amperometric Determination of Hydrazine

P.N. Deepa and S. Sriman Narayanan

A paraffin composite electrode incorporating Copper hexacyanoferrate as the mediator was prepared and used for the electrocatalytic oxidation and amperometric determination of hydrazine. It was observed that the oxidation of hydrazine to nitrogen occurs at potentials coinciding with that of Fe(CN)64/Fe(CN)63 transformation in the copper hexacyanoferrate while no significant oxidation of hydrazine was observed at the bare electrode. The application of the sensor for on-line monitoring of hydrazine was also evaluated. The modified electrode showed good stability and a linear response for hydrazine determination in the range of 1.41 x 104 M to 2.25x103 M of hydrazine with a limit of detection of 4.7 x 105 M. Also the electrode gave good recoveries in the range of 99.01 % to 100.55% for the analysis of added hydrazine in drinking water.

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In Vitro Solubilisation of Rock Phosphate by Anaerobic Cellulolytic Bacteria

V. Salom Gnana Thanga and K. Ramasamy

Anaerobic phosphate solubilisation by three cellulolytic bacteria viz., Acetivibrio sp., Bacteroides sp. and Clostridium sp. were checked in vitro under immobilised and liquid culture condition. The solubilisation was compared with different organic acids viz., acetic, butyric, citric and propionic acids. Under immobilised conditions, in the first week addition of mixed acids had maximum solubilisation (365 ppm of P/g of rock phosphate). Among the cultures, Clostridium sp. had more solubilisation than Acetivibrio sp. and Bacteroides sp. After third week, a decrease in solubilisation was observed. However in liquid culture, the three cultures had almost similar pattern of solubilisation. The phosphatase acitivity was more for Acetivibrio sp. (270-535 ppm of p-nitrophenol/g of rock phosphate) and Bacteroides sp. (150-285 ppm of p-nitrophenol/ g of rock phosphate) when crystalline cellulose was used as substrate. But Clostridium sp. was found to exhibit more activity when grown with cotton (195-415 ppm of p-nitrophenol/g of rock phosphate) as substrate.

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Interaction of Residual Anilofos or Butachlor with the dissipation of Isoproturon

S.B. Singh and G. Kulshrestha

Well known resistance of Phalaris minor against isoproturon, a urea herbicide is a severe problem in northern parts of India. Way back in 1994 it was related with the application of anilofos in place of butachlor in several rice growing areas of Haryana. In this study it has been proved that use of anilofos or butchlor has nothing to do with the faster degradation of isoproturon and hence for resistance development. But it is certainly a resistant biotype of P. minor. Residual anilofos or butachlor does not affect the dissipation pattern of isoproturon.

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Adsorption of Cadmium on Coal Fly Ash

Arnab Kumar De,

Coal fly ash, the solid waste of power plants has been used as an adsorbent for the removal of cadmium from aqueous solutions. Column studies were conducted and the effect of various parameters affecting the adsorption of cadmium on Coal Fly ash, such as bed depth, concentration of adsorbate and pH has been determined. Total adsorption of cadmium from aqueous solution was observed when the initial cadmium from aqueous solution was observed when the initial cadmium concentration was 3 mg/l or less. Adsorption of cadmium on coal fly ash conforms to Freundlichs adsorption isotherm.

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