Deepa, C S; Dr.Sugunan, S(Cochin University of Science & Technology, August , 2002)
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Abstract:
In the present work, we have tried to evaluate systematically the surface properties
of sulphated tin oxide systems modified with three different transition metal oxides viz. iron
oxide, tungsten oxide and molybdenum oxide. The catalytic activities of these systems are
checked and compared by carrying out some industrially important reactions such as
oxidative dehydrogenation of ethylbenzene and Friedel-Crafts reactions.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology
Jean John, Vadakkan; Dr. Prathapan, S(Cochin University of Science & Technology, September , 2002)
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Abstract:
In this thesis, we report our endeavours in the synthesis of a few polycyclic compounds. We were interested in the synthesis of a few bicyclic compounds designed to undergo interesting photochemical transformations including tripletmediated di-π-methane rearrangement and/or competing singlet-mediated electrocyclic reactions. Our target molecules have "inbuilt" structural features which will potentially alter the photochemistry of the substrate under consideration.The present investigation was undertaken to test our hypothesis on selective intramolecular quenching of singlet or triplet excited states of molecules.We adopted Dies-Alder reaction for the synthesis of several of the bicyclic compounds we were interested in. Some of the precursor dienes synthesised by us are capable of undergoing intramolecular cycloaddition reactions as well. So, it was important to delineate the conditions and structural features that will enable a particular molecule to undergo intermolecular and intramolecular Dies-Alder reaction when treated with a suitable dienophile.Though, the main focus of this thesis is on the synthesis of bicyclic and tricyclic systems capable of undergoing di-π-methane rearrangement, in the last chapter of this thesis, we describe our findings on the synthesis of a few dispirocompounds. These systems were encountered as unexpected products in the attempted synthesis of novel dibenzoylalkene-type systems. Consequently, a brief survey on the synthesis and transformations of dibenzoylalkenes is also included as an integral part of this thesis.
Description:
Department of Applied Chemistry, Cochin University of Science and Technology
Bindu, P C; Dr. Babu, Philip(Cochin University of Science & Technology, January , 2002)
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Abstract:
The present work is a base line attempt to investigate and assess the
toxicities of three surfactants viz. anionic sodium dodecyl sulfate (SDS), non
ionic Triton X-1OO (TX-IOO) and cationic cetyl trimethyl ammonium bromide
(CTAB). These compounds represent simple members of the often neglected
group of aquatic pollutants i.e. the anionic alkyl sulfates, non ionics and the
cationics. These compounds are widely used In plastic industry,
pesticide/herbicide formulations, detergents, oil spill dispersants, molluscicides
etc. The test organisms selected for the present study are the cyanobacterium
Synechocystis salina Wislouch representing a primary producer in the marine
environment and a fresh water adapted euryhaline teleost Oreochromis
mossambicus (peters) at the consumer level of the ecological pyramid. The fish
species, though not indigenous to our country, is now found ubiquitously in fresh
water systems and estuaries. Also it is highly resistant to pollutants and has been
suggested as an indicator of pollution in tropical region .
Description:
Department of Marine Biology, Microbiology and Biochemistry,Cochin University of Science and Technology