Vaheed, Yavari; Dr.Thomas, M M(Cochin University of Science and Technology, December , 1994)
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Abstract:
The Indian edible oyster Crassostrea madrasensis (Preston) is known to be a highly suitable candidate species for culture. Though Q, madrasensis has been subjected to intensive research, there has been no significant attempt to culture this oyster commercially. One major reason for the lack of interest in oyster culture could be the disparity in growth, survival and production reported by earlier workersf from different regions along the Indian coast. Greater predictability of production can create confidence and encourage entrepreneurs interested
in oyster culture. The present study, which is a detailed investigation on the influence of various environmental variables on growth and reproduction of Q, madrasensis, is not confined to the impact of only hydrological parameters but is also extended to study the effect of different degrees of aerial exposure on growth and survival. The main objective of the study is to develop a background for subsequent development of a site suitability index for culture of Q, madrasensis along the Indian coast. Two sets of experiments were conducted during the present study. Details of the experiments are presented in the thesis under two major chapters comprising four sections each. Each chapter has a separate introduction, materials and methods, results and discussion.
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Maya,K S; Dr.Rani,Joseph(Cochin University of Science & Technology, July , 2007)
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Abstract:
Precipitated silica is the most promising alternative for carbon black in tyre tread compounds due to its improved performance in terms of rolling resistance and wet grip.But its poor processability is a serious limitation to its commercial application.This thesis suggests a novel route for the incorporation of silica in rubbers,i.e.,precipitation of silica in rubber latex followed by coagulation of the latex to get rubber-silica maseterbatch.Composites with in situ precipitated silica showed improved processability and mechanical properties,when compared to conventional silica composites.
Description:
Department of Polymer Science and Rubber
Technology, Cochin University of Science and Technology
Sreelatha, K S; Dr.Babu, Joseph K(Cochin University of Science And Technology, June , 1990)
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Abstract:
Usually typical dynamical systems are non integrable. But
few systems of practical interest are integrable. The soliton concept is a
sophisticated mathematical construct based on the integrability of a class ol'
nonlinear differential equations. An important feature in the clevelopment.
of the theory of solitons and of complete integrability has been the interplay
between mathematics and physics. Every integrable system has a lo11g list
of special properties that hold for integrable equations and only for them.
Actually there is no specific definition for integrability that is suitable for all cases.
.There exist several integrable partial clillerential equations( pdes)
which can be derived using physically meaningful asymptotic teclmiques
from a very large class of pdes. It has been established that many 110nlinear
wa.ve equations have solutions of the soliton type and the theory of
solitons has found applications in many areas of science. Among these,
well-known equations are Korteweg de-Vries(KdV), modified KclV, Nonlinear
Schr6dinger(NLS), sine Gordon(SG) etc..These are completely integrable
systems. Since a small change in the governing nonlinear prle may cause the
destruction of the integrability of the system, it is interesting to study the
effect of small perturbations in these equations. This is the motivation of the
present work.
Description:
Department of physics, Cochin University of Science And Technology
Resmi, Varghese; Dr.Lakshmy, B(Cochin University of Science And Technology, August 29, 2013)
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Abstract:
In this thesis, certain continuous time inventory problems with positive
service time under local purchase guided by N/T-policy are analysed. In
most of the cases analysed, we arrive at stochastic decomposition of system
states, that is, the joint distribution of the system states is obtained as the
product of marginal distributions of the components.
The thesis is divided into ve chapters
Description:
Department of Mathematics
Cochin University of Science and Technology
Shylaraj, K S; Dr.Chandrasekaran,M(Cochin University of Science And Technology, August 27, 1998)
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Abstract:
In the light of the very huge demand for natural ephedrine and
pseudoephidrine, a search for an angiosperm plant containing the alkaloid ephedrine
was made and could locate Sida spp. of malvaceae family. Sida is a large genus of,
herbs and shrubs distributed throughout the tropics. About a dozen species occur in
India. The medicinally important species known are S.rhombrfolia S.cordata and
S.spinosa (Anon, 1972). Among the various species, S.rh0mbIfolia is the most widely
used one in the traditional system of medicine. An attempt was made in the present
study to develop an ideal bioprocess for the in vitro production of ephedrine from the
cell culture system of Sida rhombrfolia Linn. ssp. retusa. The callus and suspension
culture were initiated and attempts were made to enhance the yield positively by
employing various strategies like mutagenesis, immobilization and addition of
precursors, elicitors and penneabilizing agents.
Description:
Department of Biotechnology
Cochin University of Science and Technology
Manjusha, S; Dr.Sarita,Bhat G(Cochin University of Science and Technology, December , 2006)
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Abstract:
While the seriousness of the problem of antibiotic resistance is now
recognized, the complex web of resistance linking humans, animals, and the
environment is getting realized. More often, antibiotics are used as a preventive
measure against diseases. Antibiotic use for agriculture leads to the increased
resistance in the environment since antibiotics are inevitable element during
agriculture/aquaculture and antibiotic residues are excreted as waste that is frequently
spread onto farmland as organic fertilizer. Fecal bacteria survive long periods in the
environment and spread through runoff into groundwater, rivers, and marine
ecosystems.However, horizontal gene transfer occurs in the animals and guts of humans and
in a variety of ecosystems, creating a pool of resistance in the rice fields and open
waters. Even if people are not in direct contact with resistant disease through food
animals, there are chances of contact with resistant fecal pathogens from the
environment. Additionally, pathogens that are autochthonous to the environment can
acquire resistance genes from the environment. Our study revealed that autochthonous
,
bacteria Vibrio spp gained antibiotic resistance in the environment. Further, it was
evident that horizontal gene transfer occurs in Vibrio by means of plasmids, which
further augments the gravity of the problem. Non-pathogenic bacteria may also
acquire resistance genes and serve as a continuing source of resistance for other
bacteria, both in the environment, and in the human gut. As the effectiveness of
antibiotics for medical applications decline, the indiscriminate use of in aquaculture
and in humans can have disastrous conditions in future due to horizontal gene transfer
and the spread of resistant organisms: We must recognize and deal with the threat
posed by overuse of antibiotics.
Description:
Department of Biotechnology,
Cochin University of Science and Technology
Sona, A; Dr. Mukundan, M K(Central Institute of Fisheries Technology, July , 2004)
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Abstract:
In the attempt to find out catalytic potency and properties of the endoglucanase
of green mussel, it could be highlighted that the enzyme is efficient in degrading
carboxymethylcellulose to reducing sugars. The immobilized enzyme will find
applications in the food industry, paper and pulp industry, wood preservation,
alcohol and pharmaceutical industry.The purification method employed i.e. Sephadex G100 chromatography
employing affinity and exclusion principles simplify the purification procedure.Addition of Mg2+ and Co2+ at 10mM concentrations enhances endoglucanase
activity of green mussel.The immobilized endoglucanase can be used for deinking mixed office waste
paper. The endoglucanase if supplemented with exoglucanase and B-glucosidase
under appropriate conditions would help in the recycling of paper.
Seema Nair,P; Surendran,P K(Microbiology, Fermentation and Biotechnology Division Central Institute of Fisheries Technology, Faculty of Marine Sciences, November , 2000)
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Abstract:
In this study, an attempt has been made to gather enough information regarding lactic acid bacteria from fish and shellfish of tropical regions. The occurrence and distribution of lactic acid bacteria in fresh and frozen marine fish and shellfish, farmed fish and shellfish, cured and pickled fish and shellfish have been investigated. Lactic Acid Bacteria (LAB) have for centuries been responsible for the fermentative preservation of many foods. They are used to retard spoilage and preserve foods through natural fermentations. They have found commercial applications as
starter cultures in the dairy, baking, meat, fish, and vegetable and alcoholic beverage
industries. They are industrially important organisms recognized for their fermentative
ability as well as their nutritional benefits. These organisms produce various compounds
such as organic acids, diacetyl, hydrogen peroxide and bacteriocins or bactericidal
proteins during lactic fermentations.Biopreservation of foods using bacteriocin producing LAB cultures is becoming widely used. The antimicrobial effect of bacteriocins and other compounds
produced during fermentation of carbohydrates are well known to inhibit the growth of
certain food spoiling bacteria as well as a limited group of food poisoning and pathogenic bacteria LAB like Lactobacillus plantarum are widely used as starter cultures for the
Production of fish ensilage. The present study is the first quantitative and qualitative study on the
occurrence and distribution of lactic acid bacteria in fresh and frozen fish and prawn. It
is concluded that Lactobacillus plantaruni was the predominant lactobacillus species in fresh and frozen fish and shellfish. The ability of selected Lactobacillus cultures to grow at low temperatures, high salt content, produce bacteriocins, rapidly ferment sugars and decrease the pH make them potential candidates for biopreservation of fish and shellfish.
Meril, George
Beena, K S(Cochin University of Science and Technology, December 17, 2014)
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Abstract:
Leachate from an untreated landfill or landfill with damaged liners
will cause the pollution of soil and ground water. Here an attempt was made
to generate knowledge on concentrations of all relevant pollutants in soil
due to municipal solid waste landfill leachate and its migration through soil
and also to study the effect of leachate on the engineering properties of soil.
To identify the pollutants in soil due to the leachate generated from
municipal solid waste landfill site, a case study on an unlined municipal
solid waste landfill at Kalamassery has been done. Soil samples as well as
water samples were collected from the site and analysed to identify the
pollutants and its effect on soil characteristics. The major chemicals in the
soil were identified as Ammonia, Chloride, Nitrate, Iron, Nickel,
Chromium, Cadmium etc.. Engineering properties of field soil samples
show that the chemicals from the leachate of landfill may have effect on the
engineering properties of soil.
Laboratory experiments were formulated to model the field around an
unlined MSW landfill using two different soils subjected to a synthetic
leachate. The Maximum change in chemical concentration and engineering
property was observed on soil samples at a radial distance of 0.2 m and at a
depth of 0.3 m. The pollutant (chemicals) transport pattern through the
soil was also studied using synthetic leachate. To establish the effect of
pollutants (chemicals) on engineering properties of soil, experiments were
conducted on two types soils treated with the synthetic chemicals at four
different concentrations. Analyses were conducted after maturing periods of
7, 50, 100 and 150 days. Test soils treated with maximum chemical
concentration and matured for 150 days were showing major change in the
properties.
To visualize the flow of pollutants through soil in a broader sense, the
transportation of pollutants through soil was modeled using software ‘Visual
MODFLOW’. The actual field data collected for the case study was used to
calibrate the modelling and thus simulated the flow pattern of the pollutants
through soil around Kalamassery municipal solid waste landfill for an extent
of 4 km2. Flow was analysed for a time span of 30 years in which the
landfill was closed after 20 years. The concentration of leachate beneath the
landfill was observed to be reduced considerably within one year after
closure of landfill and within 8 years, it gets lowered to a negligible level.
As an environmensstal management measure to control the pollution
through leachate, permeable reactive barriers are used as an emerging
technology. Here the suitability of locally available materials like coir pith,
rice husk and sugar cane bagasse were investigated as reactive media in
permeable reactive barrier. The test results illustrates that, among these, coir
pith was showing better performance with maximum percentage reduction
in concentration of the filtrate. All these three agricultural wastes can be
effectively utilized as a reactive material.
This research establishes the influence of leachate of municipal solid
waste landfill on the engineering properties of soil. The factors such as type
of the soil, composition of leachate, infiltration rate, aquifers, ground water
table etc., will have a major role on the area of influence zone of the
pollutants in a landfill. Software models of the landfill area can be used to
predict the extent and the time span of pollution of a landfill, by inputting
the accurate field parameters and leachate characteristics. The present study
throws light on the role of agro waste materials on the reduction of the
pollution in leachate and thus prevents the groundwater and soil from
contamination
Anuradha,Krishnan; Dr.Alagarswami, K(Cochin University of Science and Technology, April , 1987)
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Abstract:
The present study has yielded a great deal of information on nutrition of pearl oyster larvae. T he formulae presented may be used effectively and with advantage in improving the larval rearing system with specific reference to nutritional aspects. It is also hoped that this is the first comprehensive study on pearl oyster larval nutrition would stimulate further detailed investigations on many of the other finer aspects of tropical bivalve larval nutrition.
Description:
Centre Of Advanced Studies In Mariculture, Central Marine Fisheries Research Institute
Joshy, N V; Dr.Jayaraj, M K(Cochin University of Science & Technology, June , 2008)
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Abstract:
The main objective of the present study is to understand different mechanisms
involved in the production and evolution of plasma by the pulsed laser ablation
and radio frequency magnetron sputtering. These two methods are of particular
interest, as these are well accomplished methods used for surface coatings,
nanostructure fabrications and other thin film devices fabrications. Material
science researchers all over the world are involved in the development of
devices based on transparent conducting oxide (TCO) thin films. Our laboratory
has been involved in the development of TCO devices like thin film diodes
using zinc oxide (ZnO) and zinc magnesium oxide (ZnMgO), thin film
transistors (TFT's) using zinc indium oxide and zinc indium tin oxide, and some
electroluminescent (EL) devices by pulsed laser ablation and RF magnetron
sputtering.In contrast to the extensive literature relating to pure ZnO and other thin films
produced by various deposition techniques, there appears to have been relatively
little effort directed towards the characterization of plasmas from which such
films are produced. The knowledge of plasma dynamics corresponding to the
variations in the input parameters of ablation and sputtering, with the kind of
laser/magnetron used for the generation of plasma, is limited. To improve the
quality of the deposited films for desired application, a sound understanding of
the plume dynamics, physical and chemical properties of the species in the
plume is required. Generally, there is a correlation between the plume dynamics
and the structural properties of the films deposited. Thus the study of the
characteristics of the plume contributes to a better understanding and control of
the deposition process itself. The hydrodynamic expansion of the plume, the composition, and SIze distribution of clusters depend not only on initial
conditions of plasma production but also on the ambient gas composition and
pressure. The growth and deposition of the films are detennined by the
thermodynamic parameters of the target material and initial conditions such as
electron temperature and density of the plasma.For optimizing the deposition parameters of various films (stoichiometric or
otherwise), in-situ or ex-situ monitoring of plasma plume dynamics become
necessary for the purpose of repeatability and reliability. With this in mind, the
plume dynamics and compositions of laser ablated and RF magnetron sputtered
zinc oxide plasmas have been investigated. The plasmas studied were produced
at conditions employed typically for the deposition of ZnO films by both
methods. Apart from this two component ZnO plasma, a multi-component
material (lead zirconium titanate) was ablated and plasma was characterized.
Description:
Department of Physics,
Cochin University of Science and Technology