Arts,K Purushotham; Radhakrishna,M(Department of Marine Geology and Geophysics,School of Marine Sciences, 2002)
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Abstract:
The main objective of the present study is to model the gravity fields in terms of lithospheric structure below the western continental margin of India (WCMI) identify zones of crustal mass anomalies and attempt to infer the location of Ocean Continent transition in the Arabian Sea. In this study, the area starting from the western shield margin to the region covering the deep oceanic parts of the Arabian Sea which is bounded by Carlsberg and Cerg and Central Indian ridges in the south, eastern part of the Indus Cone in the west and falling between 630E and 800E longitudes, and 50N - 240N latitudes has been considered. The vast amount of seismic reflection and refraction data in the form of crustal velocities, basement configuration and crustal thicknesses available for the west coast as well as the eastern Arabian Sea has been utilized for this purpose
Saly, Thomas N; Dr. Hridayanathan, C(Cochin University of Science and Technology, May , 2001)
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Abstract:
The fishing industry the world over is passing through a critical situation.The landings of marine fishes seemed to have reached saturation in major fishing areas of the world.As a general rule fisheries employing fishing gear and techniques used by small scale and artisanal fishermen either from shore or from onboard small fishing craft come under small-scale fisheries.This study on gill nets of Kerala, the fishing method depended upon by maximum fishermen of the state focuses on the importance of this selective and low energy fishing method in the marine fishing sector of the state.The study opens with the conceptual framework by briefly reviewing the crisis in the marine fisheries sector. Maximum fishermen depend upon gill net, which is, an important selective and low energy fishing gear. A review of relevant literature on aspects such as material, selectivity and techno-economic efficiency together with scope and main objectives of the study form the major part of the compass of the introductory chapter.This survey provided the inputs for selection of centres. The chapter presents the basis for selection of sample centres, sample units and methodology for field and experimental study.The subject matter of the fourth chapter is a basic study on gear aterials. The weathering resistance, which is an important criterion to assess the material performance, was studied for polyamide monofilament in comparison to polyamide multifilament and polyethylene twisted monofilament.The study provides supporting evidence of oxidation and characteristic C-O stretching in polyethylene and cyclic lactam .formation and presence of OH in polyamide.The study indicates that small mesh gill netting can be encouraged as a selective fishing method in the inshore waters with restrained use of 30 and 32 mm mesh sizes. The economic efficiency was assessed using standard indices such as rate of return, internal rate of return, pay back period, fishery income, energy efficiency and factor productivity. The effect of size and cost of capital and cost of production on the economics of operation is also discussed in this chapter. It was observed that level of technology did not have direct effect on economic performance.
Description:
Industrial Fisheries,
Cochin University of
Science and Technology
Anoo Anna, Anthony; Dr.Mary,Joseph T(Cochin University of Science and Technology, October , 2011)
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Abstract:
The literature on the involvement of developing countries in trade has focused on the effects of different aspects of globalization on firms, regions and countries. The study attempts to examine how an export based industry, locallyembedded and originated on the basis of regional strengths has been inserted into the global trade framework. Though the unit of analysis is the manufacturing export firm in the region of Kannur, it represents the entire home textile export
industry from the state of Kerala, as close to 90% of fabric exports in home furnishing material, textiles for upholstery and decoration and stitched or fused, and branded made ups are from the region. From a global perspective, how developing countries face newer trade restrictions and overcome non quota barriers by firm and region specific activities within a value chain framework is a major research area, which has already contributions from the Ludhiana woolen
cluster (Tewari,1999 ) and the Tirupur cluster in India (Cawthorne, 1995). The study contributes to the value chain literature by examining the governance and upgrading as well as how firms benefit from linkages. India has a number of export oriented agglomerations or regions where firms have been serving export markets for many years. In many cases it is no longer the supply side policy actions that determine how they are able to penetrate new markets or expand existing market share. Based on this study it becomes possible to understand how the global value chain operates in these different industries to examine whether there is a danger of immiserisation of growth or low road growth
Description:
School of Management Studies, Cochin University of Science and Technology
Jayanarayanan, S; Dr. Paulose, C S(Cochin University Of Science And Technology, December 21, 2012)
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Abstract:
The present study was designed to investigate the protective effect of
curcumin and vitamin D3 in the functional regulation of glutamatergic NMDA and
AMPA receptors in streptozotocin (STZ) induced diabetic rats. Alterations in
glutamatergic neurotransmission in the brain were evaluated by analyzing the
glutamate content, glutamate receptors - NMDA and AMPA receptors binding
parameters and gene expression, GAD and GLAST gene expression.
Immunohistochemistry studies using confocal microscope were carried out to
confirm receptor density and gene expression results of NMDA and AMPA
receptors. The role of glutamatergic receptors in pancreas was studied using the
following parameters; glutamate content, GLAST expression, glutamate receptors
- NMDA and AMPA receptor binding and gene expression. Increasing evidence in
both experimental and clinical studies suggests that oxidative stress plays a major
role in the pathogenesis of diabetes. In the present study SOD assay and GPx gene
expression were done to evaluate the activity of antioxidant enzymes in the brain
regions and pancreas. NeuroD1 and Pdx1 gene expression were performed in
pancreas of experimental rats to evaluate pancreatic islet survival. Gene
expression profiles of caspase 8, Bax, and Akt in brain regions and pancreas were
studied to understand the possible mechanism behind curcumin and vitamin D3
mediated neuroprotection and islet survival. Gene expression studies of
vitamin D3 receptor localisation in the pancreas was done to understand the
mechanism of vitamin D3 in insulin secretion. Curcumin and vitamin D3 mediated
insulin secretion via Ca2+ release were studied using confocal microscope.
Description:
Department of Biotechnology
Cochin University of Science and Technology
Sosamma,Cherian; Dr.George, Philip(Cochin University of Science And Technology, May , 1984)
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Abstract:
Alpha glucan phosphorylase plays a very
significant role in glycolysis. The inhibition and
activation of this enzyme have significant effect on
the rate of glycolysis. The rate of glycolysis is
also determined by the interconversion between the
active 3 and inactive Q forms of phosphorylase by
two specific enzymes called phosphorylase phosphatase
and phosphorylase kinase. The allosteric properties
and interconversion mechanism reported for
well—studied animal muscle phosphorylases do not
fall under a general pattern. Studies using
purified phosphorylase from marine sources are scanty.
Detailed studies using specialised tissues from more
marine animals are necessary to find the factors that
control the properties and activities of the enzyme.
This thesis is an attempt in this direction. The
thesis deals with a detailed study of the control of
the phosphorylase by both allosterism and
interconversion between the g and b forms from four
different aquatic animals of different habitat. Phosphorylase frm the four different animal muscles were purified either partially or completely and the kinetic and control properties were studied.
Description:
School of marine sciences, Cochin University of Science And Technology
Suresh, M; Dr.Pillai, U T S(Cochin University of Science and Technology, April , 2012)
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Abstract:
Demand on magnesium and its alloys is increased significantly in the automotive industry because of their great potential in reducing the weight of components, thus resulting in improvement in fuel efficiency of the vehicle. To date, most of Mg products have been fabricated by casting, especially, by die-casting because of its high productivity, suitable strength, acceptable quality & dimensional accuracy and the components produced through sand, gravity and low pressure die casting are small extent. In fact, higher solidification rate is possible only in high pressure die casting, which results in finer grain size. However, achieving high cooling rate in gravity casting using sand and permanent moulds is a difficult task, which ends with a coarser grain nature and exhibit poor mechanical properties, which is an important aspect of the performance in industrial applications. Grain refinement is technologically attractive because it generally does not adversely affect ductility and toughness, contrary to most other strengthening methods. Therefore formation of fine grain structure in these castings is crucial, in order to improve the mechanical properties of these cast components.
Therefore, the present investigation is “GRAIN REFINEMENT STUDIES ON Mg AND Mg-Al BASED ALLOYS”. The primary objective of this present investigation is to study the effect of various grain refining inoculants (Al-4B, Al- 5TiB2 master alloys, Al4C3, Charcoal particles) on Pure Mg and Mg-Al alloys such as AZ31, AZ91 and study their grain refining mechanisms. The second objective of this work is to study the effect of superheating process on the grain size of AZ31, AZ91 Mg alloys with and without inoculants addition. In addition, to study the effect of grain refinement on the mechanical properties of Mg and Mg-Al alloys. The thesis is well organized with seven chapters and the details of the studies are given below in detail.
Description:
Materials Science and Technology Division, National Institute for Interdisciplinary Science and Technology (NIIST), CSIR
John Kurian,P; Radhakrishna,M(Department of Marine Geology and Geophysics, School of Marine Sciences, 2000)
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Abstract:
The primary aim of the present study is to acquire a large amount of gravity data, to prepare gravity maps and interpret the data in terms of crustal structure below the Bavali shear zone and adjacent regions of northern Kerala. The gravity modeling is basically a tool to obtain knowledge of the subsurface extension of the exposed geological units and their structural relationship with the surroundings. The study is expected to throw light on the nature of the shear zone, crustal configuration below the high-grade granulite terrain and the tectonics operating during geological times in the region. The Bavali shear is manifested in the gravity profiles by a steep gravity gradient. The gravity models indicate that the Bavali shear coincides with steep plane that separates two contrasting crustal densities extending beyond a depth of 30 km possibly down to Moho, justifying it to be a Mantle fault. It is difficult to construct a generalized model of crustal evolution in terms of its varied manifestations using only the gravity data. However, the data constrains several aspects of crustal evolution and provides insights into some of the major events.
Jomon Jacob, P; Dr.Prathapan, S(Cochin University of Science And Technology, January 30, 2013)
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Abstract:
the thesis entitled “Ground and Excited
State Electron Transfer Reaction Between a few Anthracene
Appended Tertiary Amines and Suitable Electron Acceptors”
portrays our attempts to explore the solvent, concentration and
temperature effect of the reaction between a few (anthracen-9-
yl)methanamines with electron acceptors like DMAD, DBA and
DBE. We have also studied the effect of solvent and percentage
fluorescence quenching in the photoinduced electron transfer
reactions of these ‘donor-spacer-acceptor’ systems. Finally we
look in to the intramolecular electron transfer reactions of a few
tertiary amine appended dibenzobarrelenes and
bisdibenzobarrelenes
Description:
Department
of Applied Chemistry, Cochin University of Science and Technology
Premachandran,S K; Dr.Joy, George(Cochin University of Science And Technology, January , 1981)
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Abstract:
The thesis presents the results of the investigations on the crystallisation ‘behaviour, detect
structure end electrical properties of certain organic crystals---phthslic snhydride end potsssiun scid phthalate Hollow crystals of phthalic snhydride were grown from vapour. the norpholog of these hollow crystals were studied in detail and s. mechanism for their growth has been proposed. A closed crystal—vapour system was used to study the basal plane growth of the
whiskers and the sequential growth, observed, confirmed the mechanism suggested for hollow crystals. The dendritic crystals of phthslic enhydride were grown, both iron
the melt and solution. The observed morphologies of these dendrites ere described. Bpherulites of phthalic anhydride have been grown by the artificial initiation of nucleation, from melt and solution. The variation of the substructure oi’ these spherulites with the growth tenperature wee
investigated. The spherulitic filll having ribbon substructure were etched to reveal dislocations. A mechanism for the formation of the observed etch pattern has been suggested. the slip occurring in these ribbons were studied and the results are presented
Description:
Department of physics, Cochin University of Science And Technology
Vanaja, K A; Dr.Jayalekshmi, S(Cochin University of Science and Technology, May , 2011)
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Abstract:
In the present studies, various copper delafossite materials viz; CuAlO2,
CuGaO2, CuFeO2 , CuGa1-xFexO2, CuYO2 and CuCaxY1-xO2 were synthesised by
solid state reaction technique. These copper delafossite materials were grown in
thin film form by rf magnetron sputtering technique. In general copper
delafossites exhibit good optical transparency. The conductivity of the CuYO2
could be improved by Ca doping or by oxygen intercalation by annealing the film in oxygen atmosphere. It has so far been impossible to improve the p-type
conductivity of CuGaO2 significantly by doping Mg or Ca on the Ga site. The ptype
conductivity is presumed to be due to oxygen doping or Cu Vacancies [6].
Reports in literature show, oxygen intercalation or divalent ion doping on Ga
site is not possible for CuGaO2 thin films to improve the p-type conductivity.
Sintered powder and crystals of CuFeO2 have been reported as the materials
having the highest p-type conductivity [14, 15] among the copper and silver
delafossites. However the CuFeO2 films are found to be less transparent in the
visible region compared to CuGaO2. Hence in the present work, the solid
solution between the CuGaO2 and CuFeO2 was effected by solid state reaction,
varying the Fe content. The CuGa1-xFexO2 with Fe content, x=0.5 shows an
increase in conductivity by two orders, compared to CuGaO2 but the
transparency is only about 50% in the visible region which is less than that of
CuGaO2 The synthesis of α−AgGaO2 was carried out by two step process which
involves the synthesis of β-AgGaO2 by ion exchange reaction followed by the
hydrothermal conversion of the β-AgGaO2 into α-AgGaO2. The trace amount of
Ag has been reduced substantially in the two step synthesis compared to the
direct hydrothermal synthesis. Thin films of α-AgGaO2 were prepared on silicon
and Al2O3 substrates by pulsed laser deposition. These studies indicate the
possibility of using this material as p-type material in thin film form for
transparent electronics. The room temperature conductivity of α-AgGaO2 was
measured as 3.17 x 10-4 Scm-1and the optical band gap was estimated as 4.12 eV.
A transparent p-n junction thin film diode on glass substrate was fabricated
using p-type α-AgGaO2 and n-ZnO.AgCoO2 thin films with 50% transparency in the visible region were deposited
on single crystalline Al2O3 and amorphous silica substrates by RF magnetron
sputtering and p type conductivity of AgCoO2 was demonstrated by fabricating
transparent p-n junction diode with AgCoO2 as p-side and ZnO: Al as n-side
using sputtering. The junction thus obtained was found to be rectifying with a
forward to reverse current of about 10 at an applied voltage of 3 V.The present
study shows that silver delafossite thin films with p-type conductivity can be
used for the fabrication of active devices for transparent electronics applications.
Description:
Department of Physics,
Cochin University of Science and Technology