Raveendranath, K; Dr.Jayalekshmi, S(Cochin University of Science & Technology, July , 2008)
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Abstract:
The work presented in the thesis is centered around two important
types of cathode materials, the spinel structured LixMn204 (x
=0.8to1.2) and the phospho -oIivine structured LiMP04 (M=Fe and
Ni). The spinel system LixMn204, especially LiMn204 corresponding to
x= 1 has been extensively investigated to understand its structural
electrical and electrochemical properties and to analyse its suitability as
a cathode material in rechargeable lithium batteries. However there is
no reported work on the thermal and optical properties of this important
cathode material. Thermal diffusivity is an important parameter as far
as the operation of a rechargeable battery is concerned. In LixMn204,
the electronic structure and phenomenon of Jahn-Teller distortion
have already been established theoretically and experimentally. Part of
the present work is an attempt to use the non-destructive technique
(NDT) of photoacoustic spectroscopy to investigate the nature of the
various electronic transitions and to unravel the mechanisms leading to
the phenomenon of J.T distortion in LixMn204.The phospho-olivines LiMP04 (M=Fe, Ni, Mn, Co etc) are the
newly identified, prospective cathode materials offering extremely high
stability, quite high theoretical specific capacity, very good cycIability
and long life. Inspite of all these advantages, most of the phospho -
olivines especially LiFeP04 and LiNiP04 show poor electronic
conductivity compared to LixMn204, leading to low rate capacity and
energy density. In the present work attempts have been made to
improve the electronic conductivity of LiFeP04 and LiNiP04 by adding
different weight percentage MWNT .It is expected that the addition of
MWNT will enhance the electronic conductivity of LiFeP04 and
LiNiP04 with out causing any significant structural distortions, which
is important in the working of the lithium ion battery.
Description:
Department of Physics,
Cochin University of Science and Technology
Sindhu,O K; Dr.Surendran, P K(Central Institute of Fisheries Technology, January , 2007)
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Abstract:
A detailed study was made on the microbial quality, with special reference to food
safety, of the fish and fishery products in the retail trade in Cochin and around. Also,
farmed molluscan shellfishes like mussels and oysters were investigated for the microbial
quality including the presence of pathogenic bacteria. Special stress has been given to
monitor the incidence of coagulase positive as well as coagulase negative Staphylococcus
in these products and their relative incidence have been recorded.In the next part, the investigation was centered mainly on toxigenic S.aureus. This
is because among the Gram positive toxigenic bacteria, the Saureus with potential to
produce thermostable enterotoxins are more relavent in food safety conceming seafoods
in comparison with the Gram-negative pathogens like Salmonella and V.cholerae.The incidence, toxigenic potential and conditions of toxin production by S.aureus
have been investigated in detail. An attempt has also been made to relate the toxigenisis
with the presence of the concerned toxigenic genes in the genomes of S. aureus strains.
Sweety, Isaac; Dr.Humayoon,Kabir S(Cochin University of Science and Technology, November 3, 2008)
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Abstract:
This thesis Entitled Internet Utilization and Academic Activities of Faculty Members in the Universities of kerala: an analytical study. Today, scientific research is throwing up new discoveries, inventions and vistas by the hour. We are witnessing a veritable knowledge explosion. It is important for members of university faculty members to keep abreast of it for giving up-t-date information to their students about the new development in the subject of their study. The internet is an invaluable tool for achieving it. Most of the universities have sufficient internet facility, but the accessibility to all the faculty members is not adequate. University Libraries also provides standard supplementary service in the internet area. This study indicates differential level of awareness and utilization of the internet services by the faculty members in the areas of teaching, research and publication. However the overall impression is that the awareness and utilization is inadequate. This point to the urgent need to devise programs and schemes to promote internet utilization among the faculty members. The suggestions indicate the key areas that deserve attention by policy makers and administrators. Thanks to the internet, every new development in every field of study is just a click away for faculty members, research scholars and students.
Description:
Department of Computer Applications, Cochin University of Science and Technology
Sijikumar,S; Dr.Mohan Kumar, K(Department of Atmospheric Sciences, 2003)
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Abstract:
The main objective of the of present study are to study the intraseasonal variability of LLJ and its relation with convective heating of the atmosphere, to establish whether LLJ splits into two branches over the Arabian sea as widely believed, the role of horizonatal wind shear of LLJ in the episodes of intense rainfall events observed over the west coast of India, to perform atmospheric modeling work to test whether small (meso) scale vortices form during intense rainfall events along the west coast; and to study the relation between LLJ and monsoon depression genesis. The results of a study on the evolution of Low Level Jetstream (LLJ) prior to the formation of monsoon depressions are presented. A synoptic model of the temporal evolution of monsoon depression has been produced. There is a systematic temporal evolution of the field of deep convection strength and position of the LLJ axis leading to the genesis of monsoon depression. One of the significant outcomes of the present thesis is that the LLJ plays an important role in the intraseasonal and the interannual variability of Indian monsoon activity. Convection and rainfall are dependent mainly on the cyclonic vorticity in the boundary layer associated with LLJ. Monsoon depression genesis and the episodes of very heavy rainfall along the west coast of India are closely related to the cyclonic shear of the LLJ in the boundary layer and the associated deep convection. Case studies by a mesoscale numerical model (MM5) have shown that the heavy rainfall episodes along the west coast of India are associated with generation of mesoscale cyclonic vortices in the boundary layer.
Anila, E I; Dr.Jayaraj, M K(Cochin University of Science & Technology, March , 2008)
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Abstract:
This thesis has focused on the synthesis and analysis of some important
phosphors (nano, bulk and thin film) for display applications. ACTFEL
device with SrS:Cu as active layer was also fabricated.Three bulk phosphors: SrS:Cu,CI; SrS:Dy,Cl; and SrS:Dy,Cu,Cl were
synthesized and their structural, optical and electrical properties were
investigated. Special emphasis was given to, the analysis of the role of
defects and charge compensating centers, on the structural changes of the
host and hence the luminance. A new model describing the sensitizing
behaviour of Cu in SrS:Dy,Cu,Cl two component phosphor was introduced.
It was also found that addition of NH4CI as flux in SrS:Cu caused
tremendous improvement in the structural and luminescence properties.A novel technique for ACTFEL phosphor deposition at low temperature was
introduced. Polycrystalline films of SrS:Cu,F were synthesized at low
temperature by concomitant evaporation of host and dopant by electron
beam evaporation and thermal evaporatin methods.Copper doped strontium sulphide nanophosphor was synthesized for the first
time. Improvement in the luminescence properties was observed in the
nanophosphor with respect to it' s bulk counterpart.
Description:
Department of Physics,
Cochin University of Science and Technology
Gopalakrishna Pillai,N; Dr.Damodaran,R(Cochin University of Science And Technology, December , 1978)
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Abstract:
In this thesis a detailed sampling is conducted using grabs and dredges to access the qualitative
and quantitative nature of the macrobenthos. A11 the animal contributing to the fauna are identified and their pattern of distribution and seasonal abundance are discussed. Affinity and diversity of polychaete fauna have also been studied. Importance of different benthic forms and their contribution to the standing crop are studied in detail. Trophic relationship between macrofauna and botton feeding commercially important fishes and prawns are also
given attention. The physico-chemical aspects or the environment have been studied and their relation to the distribution and abundance of bottom fauna has been discussed. Environmental
parameters such as temperature. salinity and dissolved oxygen. both in bottom and in the overlying waters. and rainfall were studied along with the benthos investigations. The physico-chemical nature of the sediments was also subjected to investigation. Influence of
all those ecological parameters on the bottom fauna is discussed. A detailed quantitative faunal list of maorobenthio species and a brief systematic account of the polychaeta are also given.
Description:
School of marine sciences, Cochin University of Science And Technology
Dalia Susan Vargis; Pillai, N G K(Cochin University of Science and Technology, April , 2005)
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Abstract:
In this present study macro benthos of minicoy island lakshadweep, an attempt has been made to study the distribution and community structure of benthos at different ecosystems. The main objectives of the study include the identification of benthic fauna, their distribution and composition, standing stock, qualitative and quantitative nature in relation to hydrography,seasons and sediment texture, community structure analysis and tropic relationships. This base line study at Minicoy,thus establishes that the benthos of sea grass and mangrove ecosystems(nursery grounds) determines the richness and diversity of demersal fish fauna at the nearby lagoon and reef areas to a great extent. Any serious stress on these ecosystems may lead to disappearance of certain fish species in the nearby future
Abdul Jaleel, K U; Dr.Damodaran,R(October 21, 2013)
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Abstract:
This thesis Entitled macrobenthos of the continental margin (200-1000m) of south eastern arabian sea with special reference to polychaetes. The continental margins are geologically complex and hydrodynamically active regions of the ocean, where vital biogeochemical processes take place from a global perspective. The Eastern Arabian Sea is one of the most productive regions of the world, and as a result, vast amount of organic matter is supplied to the sub surface waters and sea bed of the Arabian Sea. In this study, data on faunal abundance, standing crop and faunal composition, together with sedimentary and environmental parameters were collected from three depths (200m, 500m & 1000m) in nine bathymetric transects along the South Eastern Arabian Sea (from Cape Comorin to Karwar) during three surveys. In the present study, five textural classes of sediments were identified
from the SEAS margin, viz. sand, silty sand, sandy silt, clayey silt and admixture of sand, silt and clay. The composition of sand was higher in the southern region and decreased progressively towards the north. On the shelf edge and upper slope regions in the south (Cape to Kollam) in particular, sandy
sediments dominated .
Description:
School of Marine Sciences, Department Marine biology,Microbiology and Biochemistry
Joydas,T V; Damodaran,R(School of Marine Sciences, 2002)
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Abstract:
The work was carried out with an objective to know the quantitative and qualitative nature of the macrobenthos in relation to the existing hydrographical parameters and sediment characteristics. With the above two cruises were conducted to collect materials. Representative samples were collected from each degree square of the western continental shelf. The study deals with the hydrographic parameters. The bottom water temperature, salinity and dissolved oxygen were measured. The findings showed variations according to depth and latitude. The study gives the details of sediment characteristics of the study area. 7 different types of substrata were noticed. It also explains the macro faunal composition and diversity, and the standing stock of macrobenthos. The wet-weight and numerical abundance of macrobenthic groups are included. The thesis discusses the relation between hydrography and macrobenthos, and sediment characteristics and macrobenthos, based on the results obtained by statistical analysis of the data. It also investigates the relation between macrobenthos and fishery.
Prema, K H; Dr. Philip, Kurian(Cochin University of Science and Technology, September , 2007)
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Abstract:
In the present study the preparation and characterisation of rubber ferrite
composites containing nickel ferrite and gamma ferric oxide have been dealt with.Synthetic rubbers viz. ethylene propylene diene rubber and neoprene rubber were used
for the incorporation of nickel ferrite and gamma ferric oxide for the synthesis of
RFCs. Incorporation of ferrites were carried out according to a specific recipe for
various loadings of the magnetic fillers. The ferrites used for the preparation of RFCs
were synthesised using sol-gel method and structural characterisation was carried out.
Experimental techniques like X-ray diffraction, Transmission electron microscopy and
other analytical techniques were used for this. Precharaterised ferrites were then
incorporated at different loading into rubber according to conventional mixing
methods. The cure characteristics, mechanical, dielectric, magnetic and microwave
properties of these composites were evaluated. The effect of carbon black on these
properties of RFCs were carried out.
Description:
Department of Polymer Science and Rubber Technology,
Cochin University of Science & Technology