Neil, Scholastin Correya; Dr.Rosamma,Philip(Cochin University of Science And Technology, October , 2012)
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Abstract:
The marine environment is indubitably the largest contiguous habitat on
Earth. Because of its vast volume and area, the influence of the world ocean on
global climate is profound and plays an important role in human welfare and
destiny. The marine environment encompasses several habitats, from the sea
surface layer down through the bulk water column, which extends >10,000 meters
depth, and further down to the habitats on and under the sea floor. Compared to
surface habitats, which have relatively high kinetic energy, deep-ocean circulation
is very sluggish. By comparison, life in the deep sea is characterized by a relatively
constant physical and chemical environment. Deep water occupying the world
ocean basin is a potential natural resource based on its properties such as low
temperature, high pressure and relatively unexplored properties. So, a judicious
assessment of the marine resources and its management are essential to ensure
sustainable development of the country’s ocean resources.
Marine sediments are complex environments that are affected by both
physiological and biological factors, water movements and burrowing animals.
They encompass a large extent of aggregates falling from the surface waters. In
aquatic ecosystems, the flux of organic matter to the bottom sediments depend on
primary productivity at the ocean surface and water depth. Over 50% of the earth’s
surface is covered by deep-sea sediments that are primarily formed through the
continual deposition of particles from the productive pelagic waters (Vetriani et al.,
1999). These aggregates are regarded as ‘hot spots’ of microbial activity in the
ocean (Simon et al., 2002). This represents a good nutritional substrate for
heterotrophic bacteria and favours bacterial growth
Description:
School of Marine Sciences, Cochin University of Science And Technology
Santhi, Thirumani S; Dr.Chandrika, V(Cochin University of Science And Technology, June , 1992)
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Abstract:
The principal interest of the present investigation was to determine
seasonal and vertical variation of chemoorganotrophic utilisation of glucose
and sodium—acetate by the natural bacterial population in the aquaculture
pond of Narakkal, Cochin using techniques which allow maintenance of
the in situ gaseous concentrations during incubation. In addition salinity,
dissolved oxygen, temperature, hydrogen—ion—.concentration, primary production,
plant pigments and total bacterial concentration were determined
seasonally and vertically because of their possible relationship to chemoorganotrophy.
Hamsakutty, V; Dr.Mathew, K T(Cochin University of Science and Technology, March , 2007)
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Abstract:
In this thesis, the author proposes a new geometry DR antenna-the Hexagonal Dielectric Resonator Antenna(HDRA)-capable of multiple frequency operation on a single feed of excitation.This avoids the conventional use of miniaturizes the structure.The properties of the HDRA on microstrip as well as coaxial feeding have been studied.The analysis of radiation characteristics indicates a gain comparable with other shapes.The antenna is capable of providing efficiency around 98%.The simulation using HFSS also yields results in conformity with the experimental results.Mode analysis is carried out and the modes are identified.The determination of the reflection characteristics through theoretical analysis using FDTD validates the multifrequency operation of the antenna,The antenna finds application in DCT,PCS and WLAN bands.
Description:
Department of
Electronics, Cochin University of Science and Technology
Vimalkumar, T V; Dr.Vijayakumar, K P(Cochin University of Science & Technology, August , 2011)
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Abstract:
In the present work we report the preparation details studies on ZnO thin films. ZnO
thin films are prepared using cost effective deposition technique viz., Chemical Spray
Pyrolysis (CSP). The method is very effective for large area preparation of the ZnO thin
film. A new post-deposition process could also be developed to avoid the adsorption of
oxygen that usually occurs after the spraying process i.e., while cooling. Studies were done
by changing the various deposition parameters for optimizing the properties of ZnO thin
film. Moreover, different methods of doping using various elements are also tried to
enhance the conductivity and transparency of the film to make these suitable for various
optoelectronic applications.
Description:
Department of Physics,
Cochin University of Science and Technology