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Electrical Studies on the Composite of Polyaniline with Zinc
Oxide Nanoparticles
-- Shahid Pervez Ansari and Faiz Mohammad
Inorganic/organic composites of polyaniline (PANI) with zinc
oxide (ZnO) nanoparticles as inorganic filler have
been prepared by solution casting method using N-methyl-2-pyrrolidone (NMP) as solvent. These composites
are studied for their electrical conductivity and stability in terms of DC electrical conductivity retention using
four-in-line probe technique under isothermal and cyclic heating of the test samples.
The composites have also been characterized by Fourier Transform Infrared
(FTIR) spectroscopy. It has been found that in
composites, there exist two conduction phases, as electrical conductivity first decreases with
decrease in concentration of PANI. However, with the increase in concentration of ZnO nanoparticles
further, the electrical conductivity of the composites increases. All the samples follow Arrhenius equation for the temperature
dependence of electrical conductivity and support the semiconducting nature of the doped state. The conductivity of the
as-prepared composites has been found to be in the
semiconducting region. The studied samples showed
good electrical conductivity stability up to the temperature of
90 °C.
© 2010 IUP. All Rights Reserved.
Quantitative Risk Assessment (Qra)
of a Petroleum Refinery
-- Kailas L Wasewar and M Siva Kumar
The diversity in the products manufactured by Chemical Process Industry (CPI) has made it more and
more common to use reactors, conduits and storage vessels, where hazardous substances are handled at
extreme conditions. The accidental release of the inventory results in toxic vapor release, fires and explosions that
have potential offsite consequences. The increased public awareness towards this issue has prompted the
authorities to develop tools and techniques for evaluating the risk of CPIs. Quantitative Risk Assessment (QRA) is
utilized as a tool to evaluate the risk posed to the society from the process and storage facilities. For the present study,
a petroleum refinery was chosen. Typically, a refinery consists of myriad chemicals that are inherently
flammable, toxic and hazardous. The processing and the storage of the materials that have potential offsite
consequences were analyzed. The present paper describes the hazard scenarios considered, the risk assessment
procedure, selection and application of data for consequence analysis, estimating the frequency of occurrence of the
event. Various changes are recommended to ensure that the risk posed to the society is within the acceptable region.
© 2010 IUP. All Rights Reserved.
Fly Ash Catalyzed Friedel-Crafts Cinnamoylation Reaction in
Solvent-Free Conditions:
Synthesis of a, b-Unsaturated Ketones
Under Microwave Irradiation
-- G Thirunarayanan
Several aromatic hydrocarbons have been cinnamoylated using
fly ash catalyzed
Friedel-Crafts acylation method in solvent-free conditions under microwave irradiation for facile and
rapid synthesis of good yields of E-2-propen-1-ones. The fly ash can be removed by simple washing with diethyl
ether. Thus, this paper describes a new greener method for synthesis of aryl styryl ketones. Moreover, activated
substrates undergo cinnamoylation predominantly at the
para position.
© 2010 IUP. All Rights Reserved.
Synthesis and Characterization of
Dichlorobis(Embelinate)Copper(II) Complex
-- V Usha Rani, D Venkat Rao, M S Prasada Rao and B B V Sailaja
Dichlorobis(embelinate)copper(II) complex was obtained by the reaction of copper chloride with embelin
in 1:2 molar proportion. The thermal decomposition behavior of the complex was studied
using Thermogravimetric Analysis (TGA). The coordination of copper(II) through the carbonyl and hydroxyl
oxygen atoms of embelin was evident from the infrared (IR) analysis. Elemental, atomic absorption
spectrophotometric and X-ray diffraction analyses of the complexes gave values that are consistent with six coordinate
octahedral geometry of the metal ions. Based on the data from these physicochemical investigations, the molecular
formula of the complex was proposed as
Cu(C17H25O4)2 Cl2.
© 2010 IUP. All Rights Reserved.
Groundwater Pollution: An Overview
-- M K Sharma and V K Choubey
Groundwater plays an important role in our life support system as it is being used for different designated
uses, especially drinking purpose. But due to unplanned urban development and development in both industrial
and agricultural sectors, groundwater quality has
deteriorated, resulting in groundwater pollution. Groundwater
pollution has become a worldwide problem nowadays. Diffusion of urban sources like runoff from city streets,
gardening and commercial activities in urban environment and effluents from industrial sites also aggravate the problem
of groundwater pollution. Even some workers have reported the presence of pesticides in the groundwater
beyond the permissible limit. The pesticides join the watercourses through different
pathwaysthe runoff from agricultural lands, industrial and urban
effluents, spray operations for crop and disease vector
control, etc.and may ultimately reach the groundwater through infiltration and percolation. The pesticides may impart toxicity to the
groundwater and cause various health hazards. A number of studies have been carried out by different workers covering
the water quality aspects of groundwater. In the present paper, the status of the groundwater quality of India has
been discussed.
© 2010 IUP. All Rights Reserved.
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