Binoy,Jose; Prathapan,S(Cochin University of Science and Technology, March , 2000)
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Abstract:
The aim of the study is to synthesise several dibenzoylakene-type systems such as acenaphthenone-2-ylidene ketones 47 and phenanthrenone-9-ylidene ketones 48 by the condensation reaction of acenaphthenequinone and phenanthrenequinone
with methyl ketones. Here studies the thermal and photochemical transformations of acenaphthaenone-2-ylidene ketones 3a-c.These acenaphthenone –2-ylidene ketones underwent extensive decomposition on heating. The objectives of present study is to synthesise acenaphthenone-2-ylidene ketones by the Claisen-Schmidt condensation of acenaphthenequinone and methyl ketones, it is to synthesise phenanthrenone –9-ylidene ketones by the Claisen-Schmidt condensation of phenanthrequinone and methyl ketones, thermal studies on acenaphthenone-2-ylidene ketones and phenanthrenone-9-ylidene ketones, photochemical studies on acenaphthenone-2-ylidene ketones and phenanthrenone –9-ylidene ketones to establish the generality of dibenzoyalkene rearrangement. Cyclic voltammetric studies on these dibezoyalkenes to compare their redox behaviour with that of the cis and trans isomers of dibenzoyl-ethylene, dibenzoylstilbene. These results should provide some information about their reactivity, and to assess and exploit the potential of these systems as quinonemethides. This study conclude that a number of new dibenzolalkene-type systems have been synthesized by the Claisen-Schmidt condensation of 1,2-diketones such as phenanthequinone and acenaphthenequinone with methyl ketones. Some of these compounds have been shown to undergo interesting photochemical transformations. Based on the results it is conclude that phenanthjrenone-9-ylidene ketones are excellent Michael acceptors. Methanol adds to these to yield the corresponding furanols. These furanols are unstable and are slowly converted to phenanthro-2 (3H)-furanones
Jose David, P; Dr.Paul, Vatakencherry A(Cochin University Of Science And Technology, February 17, 1989)
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Abstract:
In the present work different new approaches for the synthesis
of Vitamin A are investigated. In these synthetic schemes, all the
twenty carbon atoms of the target molecule are derived either fully
from components isolated from common essential oils or partially from
commercially available materials. By retrosynthetic analysis, Vitamin A molecule can be disconnected into a cyclic and a linear unit. Different methods for the synthesis of the linear and the cyclic components are described.
The monoterpenes, geraniol and citral, major constituents of
palmarosa and lemongrass oils, have the required basic carbon framework
for consideration as starting materials for the synthesis of Vitamin A.
The potential of these easily available naturally occurring compounds
as promising starting materials for Vitamin A synthesis is demonstrated.
Organoselenium and organosulfur mediated functional group transformations
for the synthesis of the functionalised conjugated C10 linear components
(ie., the dimethyloctatriene derivatives) are reported. The classical
approaches as well as the attempted preparation of cyclic C10 and C13
units employed in the present study as intermediates for Vitamin A
synthesis are described. The utility of commercially available materials namely 2-acetylbutyrolactone and levulinic acid in -the preparation of C5 intermediates for Vitamin A synthesis is demonstrated.
Description:
Department Of Applied Chemistry
Cochin University Of Science And Technology
Madhusoodana Kurup,B; Dr.Samuel, C T(Cochin University of Science and Technology, July , 1982)
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Abstract:
The thesis documents a comprehensive systematic account of Vembenad lake fishes and to study the effect of physico-chemical parameters on the distribution and abundance of fishes in the lake. This study is expected to advance the knowledge on the biological aspects of two commercially important fishes of the lake which are very desirable for brackish water fish farming. Additionally, the results of the studies on the ecology as habitat, occurrence, season and abundance of all the recorded fishes of the lake end the commercially important fish species of the lake are also incorporated. A general appraisal on the detrimental factors which are adversely affecting the fisheries resources of the lake are presented and some measures of conservation are also suggested. The results of the present study are helpful in formulating suitable schemes for management of parts of the Vembenad lake for capture and culture fisheries
Description:
School of Marine Science, Cochin University of Science and Technology
Radhakrishnan Nair,P N; Dr.Ramachandran Nair,P V(Cochin University of Science and Technology, April , 1983)
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Abstract:
Rainbow sardines of the genus belonging
to the family Dueenaieriidae. are small pelagic fishes
forming a fairly good, though not abundant. seasonal fishery
all along the coasts of India inhabiting the coastal waters.
There have been some earlier reports on such individual
aspects as their systematic, distribution, abundance.
Ostecology and a few biological factors but no attempt has
been made towards a comprehensive study on this group. Two
species of rainbow sardines are known to occur in the Indian
seas and while a knowledge about their biology would be
useful from the fishery point of view. it was also thought
a study of their systematic position, especially regarding
the identity or the two species which had raised doubts
among earlier workers would lead to a better understanding
or the group as a whole. This thesis is mainly based on
studies during the period from April 1969 to march 1971 with
a continued investigation of fishhery aspects till December
1975. from the Gulf of manar: and the Palk Bay around
mandapam area. on the south-east coast of India. Thus the
work deals with the systemtics, biology and fishery of
rainbow sardines of Indian seas.
Priyalakshmi, G; Dr.Ravindranatha Menon,N(Cochin University of Science and Technology, September , 2008)
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Abstract:
The oceans in their expanse cover, seven - tenths of the Earth surface. Despite being restricted in size, the littoral zone or the intertidal zone (beach) has the greatest variation in environment factors of any marine area .Stemming from this variation ,a treamendous diversity of life, which may be great as or greater than that found in the more extensive sub tidal habits exist in this realm. the study beaches harbour diverse and abundant assemblage of marine organisms. Besides macro funna, microscopic organisms belonging to the lower and higher invertebrate taxa profusely inhabit these beaches. The ecological realm where these animals exist is known as the interstitial environment, which in principle includes the pore spaces in between the sand grains containing copious supply of nutrient rich oxygenated seawater. An astonishing diversity of taxa could be found within the interstitial fauna.
Bellarmine,K C; Dr.Shahul,Hameed M(Cochin University of Science and Technology, August , 1991)
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Abstract:
Trawling, despite being heavily energy expensive, still continues to be the most energy expensive fishing method particularly so in View of the export oriented nature of the Indian seafood industry. This study therefore aims at analyzing the efficiency of trawls operation from Cochin, an important fishing center along the southwest coast of India. The analysis is made along two perspectives - economic and technological. Even though technological efficiency complement economic efficiency, in the fishing parlance, parameters like the size composition of the catch, selectivity factors, etc., will have a direct bearing on the technological qualities of the trawl, and which parameters will have a significant impact on the effective exploitation of a fishery stock. Whereas the technological analysis aims at improving the efficiency with regard to the effective utilization of fuel and fishery stocks, economic analysis ascertains the present status of the trawling operations from the commercial angle.
Description:
Department of Industrial Fisheries,School of Marine Science, Cochin
University of Science and Technology
Mohan, M V; Dr.Cheriyan, P V(Cochin University of Science And Technology, March , 1979)
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Abstract:
Teredinids (shipworms), a group of wood boring bivalves occurring in the Cochin Harbour region have been taken up for the eco-physiological studies. On the ecological part, the occurrence, abunance and seasonal intensity of the teredinids in relation to hydrographic conditions have been studied. On the physiological part, salinity tolerance and oxygen
consumption of the most commonly occurring shipworms, Nausitcra hedlgyi
and Teredo furcifera have been investigated. The hydrographic factors studied are temperature, salinity, dissolved oxygen, phosphate, nitrite, silicate and pH. The variation in temperature is found to be comparatively narrow. But seasonal variation in salinity, dissolved oxygen, phosphate, nitrite and silicate has been observed, with the highest values during the monsoon period. In the case of pH, the minimum value has been obtained during the low saline period and
the maximum value, during the high saline period. Of the various hydrographic factors studied, salinity has been found to be the most important fluctuating environmental parameter influencing the life of organisms in the habitat.
Description:
School of marine sciences, Cochin University of Science And Technology
Unnikrishnan, K P; Dr. Eby Thomas, Thachil(DEPARTMENT OF POLYMER SCIENCE AND RUBBER TECHNOLOGY, January , 2006)
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Abstract:
This thesis aims to develop new toughened systems for epoxy resin via physical and chemical modifications. Initially the synthesis of DGEBA was carried out and the properties compared with that of the commercial sample. Subsequently the modifier resins to be employed were synthesized. The synthesized resin were characterized by spectroscopic method (FTIR and H NMR), epoxide equivalent and gel permeation chromatography. Chemical modification involves the incorporation of thermoset resins such a phenolics, epoxy novolacs, cardanol epoxides and unsaturated polyester into the epoxy resin by reactive belnding. The mechanical and thermal properties of the blends were studied. In the physical modification route, elastomers, maleated elastomers and functional elastomers were dispersed as micro-sized rubber phase into the continuous epoxy phase by a solution blending technique as against the conventional mechanical blending technique.
The effect of matrix toughening on the properties of glass reinforced composites and the effect of fillers on the properties of commercial epoxy resin were also investigated. The blends were characterized by thermo gravimetric analysis, differential scanning calorimetry, dynamic mechanical analysis, scanning electron microscopy and mechanical property measurements. Among the thermoset blends, substantial toughening was observed in the case of epoxy phenolic novolacs especially epoxy para cresol novolac (ECN). In the case of elastomer blending , the toughest blends were obtained in the case of maleic anhydride grafted NBR. Among functional elastomers the best results were obtained with CTBN. Studies on filled and glass reinforced composites employing modified epoxy as matrix revealed an overall improvement in mechanical properties
Rajalekshmi Amma, P; Dr.Mohandas, A(Cochin University of Science And Technology, 1992)
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Abstract:
Industrialisation affects air, water, and soil. Industrial
effluents which enter the aquatic environment either by direct
disposal or through run off, affect living organisms at
morphological and physiological levels. In any living tissue
toxic materials exert their effects first at molecular and
biochemical levels (Robbins and Angell, 1976). Most of the
industrial effluents contain elevated concentrations of organic
and inorganic chemicals capable of eliciting stimulatory or
inhibitory effects on the metabolism of aquatic organisms.
Heavy metals form an important group of environmental
pollutants. Effects of pollution on the aquatic environment by
heavy metals have received considerable attention in recent years
due to their toxicity even at very low levels, persistence in the
environment, and chances of getting biomagnified. A pollutant
that does not affect a particular process under normal unstressed
condition may affect the ability of the animal to adjust to
changing environmental conditions which ultimately decrease its
chances of survival (Thurberg et al., 1973
Description:
School of Environmental Studies, Cochin University of Science And Technology
Gopalakrishnan, K S; Dr.Kuttyamma, V J(Cochin University of Science and Technology, February , 1990)
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Abstract:
The present study involved investigation of the lethal and sublethal effects of three pesticides individually. The pesticides are the commercial formulations of DDT (organochlorine).Dime—
cron (organophosphate) and Gramoxone (paraquat dichloride).Aspects like individual toxicity, modulations in the activities of some selected enzymes, consequent to exposure to sub lethal levels of pesticides, sub lethal effects onperipheral haematology and alterations caused on the tissue architecture of brain, gills and liver, have been documented. Attempts have been made to analyse the impact of pesticides, added at realistic Levels to the experimental media, on the life and activity of Etroplus maculatus
Description:
Division of Pkuflxua Biology, Microbiology and Biochemistry, School of Marine Sciences, Cochin University of Science and Tehnology
Madhu, G; Dr.George, K E(Cochin University of Science and Technology, January , 1994)
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Abstract:
The present study was undertaken to evaluate the
effectiveness of a few physico-chemical and biological
methods for the treatment of effluents from natural rubber
processing units. The overall objective of this study is to evaluate
the effectiveness of certain physico-chemical and biological
methods for the treatment of effluents from natural rubber
processing units. survey of the chemical characteristics
of the effluents discharged from rubber processing units
showed that the effluents from latex concentration units were
the most polluting
Description:
Department of Polymer Science and Rubber Technology,
Cochin University of Science and Technology
Ambika, G; Dr.Babu, Joseph K(Cochin University of Science And Technology, March , 1988)
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Abstract:
It has become clear over the last few years that many deterministic dynamical systems described
by simple but nonlinear equations with only a few variables can behave in an irregular or
random fashion. This phenomenon, commonly called deterministic chaos, is essentially due to the fact that we cannot deal with infinitely precise numbers. In these systems trajectories emerging from nearby initial conditions diverge exponentially as time evolves)and therefore)any small error in the initial measurement spreads with time considerably, leading to unpredictable and chaotic behaviour The thesis work is mainly centered on the asymptotic behaviour of nonlinear and nonintegrable dissipative dynamical systems. It is found that completely
deterministic nonlinear differential equations describing such systems can exhibit random or chaotic behaviour. Theoretical studies on this chaotic behaviour can enhance our understanding of various phenomena such as turbulence, nonlinear electronic circuits, erratic behaviour of heart and brain, fundamental molecular reactions involving DNA, meteorological phenomena, fluctuations in the cost of materials and so on. Chaos is studied mainly under two different
approaches - the nature of the onset of chaos and the statistical description of the chaotic state.
Description:
Department of physics, Cochin University of Science And Technology