Kriashnan Nair, P R; Nandakumaran, V M; Ambika, G(Pramana, December , 1994)
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Abstract:
We establish numerically the validity of Huberman-Rudnick scaling relation for
Lyapunov exponents during the period doubling route to chaos in one dimensional maps. We
extend our studies to the context of a combination map. where the scaling index is found to
be different.
Sunil,K Narayanankutty(Gordon and Breach Science Publishers, December 10, 1991)
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Abstract:
Tear and wear properties of short kevlar fiber, thermoplastic polcurethane (TPU) composite with
respect to fiber loading-and fiber onentation has been studied and the fracture surfaces were examined
under scanning electron microscope (SEM). Tear strength first decreased up to 20 phr fiber loading
and then gradually increased with increasing fiber loading. Anisotropy in tear strength was evident
beyond a fiber loading of 20 phr. Tear fracture surface of unfilled TPU showed sinusoidal folding
characteristics of high strength matrix. At low fiber loading the tear failure was mainly due to fibermatrix failure whereas at higher fiber loading the failure occurred by fiber breakage. Abrasion loss
shows a continuous rise with increasing fiber loading, the loss in the transverse orientation of fibers
being higher than that in the longitudinal orientation. The abraded surface showed lone cracks and
ridges parallel to the direction of abrasion indicating an abrasive wear mechanism. In the presence of
fber the abrasion loss was mainly due to fiber low.
Chandran,A R; Gopikrishna, M; Aanandan,C K; Mohanan, P; Vasudevan, K(Progress In Electromagnetics Research, 2007)
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Abstract:
The scattering behaviour of fractal based metallodielectric structures loaded over metallic targets of different shapes such as flat plate, cylinder and dihedral corner reflector are investigated for both TE and TM polarizations of the incident wave. Out of the various fractal structures studied,square Sierpinski carpet structure is found to give backscattering reduction for an appreciable range of frequencies. The frequency of minimum backscattering depends on the geometry of the structure as well as on the thickness of the substrate. This structure when loaded over a dihedral corner reflector is showing an enhancement in RCS for corner angles other than 90◦.
A comprehensive overview of reclamation of cured rubber with special emphasis on latex reclamation is depicted in this
paper. The latex industry has expanded over the years to meet the world demands for gloves, condoms, latex thread, etc.
Due to the strict specifications for the products and the unstable nature of the latex as high as 15% of the final latex
products are rejected. As waste latex rubber (WLR) represents a source of high-quality rubber hydrocarbon, it is a
potential candidate for generating reclaimed rubber of superior quality. The role of the different components in the
reclamation recipe is explained and the reaction mechanism and chemistry during reclamation are discussed in detail.
Different types of reclaiming processes are described with special reference to processes, which selectively cleave the cross
links in the vulcanized rubber. The state-of-the-art techniques of reclamation with special attention on latex treatment are
reviewed. An overview of the latest development concerning the fundamental studies in the field of rubber recycling by
means of low-molecular weight compounds is described. A mathematical model description of main-chain and crosslink
scission during devulcanization of a rubber vulcanizate is also given.
Bindu, Krishnan; Nampoori, V P N(Indian Academy of Sciences, June , 2005)
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Abstract:
Nanosized ZnO was prepared by polyol synthesis. Fluorescence spectrum of the ZnO colloid at varying pump intensities was studied. The powder was extracted and characterized by XRD and BET. The extracted powder was screen printed on glass substrates using ethyl cellulose as binder and turpinol as solvent. Coherent back scattering studies were performed on the screen printed sample which showed evidence of weak localization. The screen printed pattern showed strong UV emission.
Haneesh Kumar,V; Samsuddin,M(Centre for Earth Science Studies, 2001)
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Abstract:
In the present investigation, an attempt is made to document various episodes of transgression and regression during the late Quaternary period from the study of coastal and shelf sequences extending from the inland across the beach to the shelf domain. Shore parallel beach ridges with alternating swales and occurrence of strand line deposits on the shelf make the northern Kerala coast an ideal natural laboratory for documenting the morpho-dynamic response of the coast to the changing sea level. The objectives of the study are lithographic reconstruction of environments of deposition from the coastal plain and shelf sequences; documentation of episodes of transgression and regression by studying different coastal plain sequences and shelf deposits and evolve a comprehensive picture of late Quaternary coastal evolution and sea level changes along the northern Kerala coast by collating morphological, lithological and geochronological evidences from the coastal plain and shelf sequences. The present study is confined to two shore-normal east-west trending transects, Viz. Punjavi and Onakkunnu, in the northern Kerala coast.
Navaneeth, P; Dr. Ramesh Babu, T; Dr. Robert K Plunkett(Cochin University of Science and Technology, July 11, 2016)
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Abstract:
Experimental Neutrino Physics is an active area of research in high energy
physics. The investigation of the properties of this elusive particles
has started since it’s discovery itself. In the standard model of particle
physics, neutrinos are massless, the discovery of neutrino oscillation is the
first evidence that demands the extensions of standard model. It is well
established the existence of three active neutrinos, e, μ and , but recent
experiments like LSND and MiniBooNE has found some anomalies
in their data. These experimental data could not be explained using three
flavour neutrino oscillation physics, but they could explain the anomaly
by adding a fourth type neutrino called sterile neutrinos. The evidences
obtained from these experiments are not yet conclusive. Search for sterile
neutrino is an extensive research area in the field of neutrino physics. The
main work presented in this thesis is a sterile neutrino search at MINOS
(Main Injector Neutrino Oscillation Search) experiment at Fermilab, USA.
MINOS is a two detector experiment at Fermilab, which studies the
neutrinos produced at Fermilab Main Injector particle accelerator. MINOS
Near Detector is situated at 1 km away from the source and the Far
Detector is at Soudan Mine at Minnesota, 735 km away from the neutrino
source. The experiment is built to study neutrino oscillation phenomena
in the atmospheric sector and has made world class measurements on neutrino
oscillation parameters. The MINOS experiment is also capable of
looking for small perturbation in the energy spectra caused by any fourth
type of neutrino and can extract the oscillation parameters.
Srinivas, K; Dr. Rao, R R(Cochin University of Science and Technology, April , 1999)
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Abstract:
This thesis entitled seasonal and interannual variability of sea level and associated surface meteorological parameters at cochin.The interesting aspect of studying sea level variability on different time scales can be attributed to the diversity of its applications.Study of tides could perhaps be the oldest branch of physical oceanography.The thesis is presented in seven chapters. The first chapter gives, apart from a general introduction, a survey of literature on sea level variability on different time scales - tidal, seasonal and interannual (geological scales excluded), with particular emphasis on the work carried out in the Indian waters. The second chapter is devoted to the study of observed tides at Cochin on seasonal and interannual time scales using hourly water level data for the period 1988-1993. The third chapter describes the long-term climatology of some important surface oceanographic and meteorological parameters (at Cochin) which are supposed to affect the sea level. The fourth chapter addresses the problem of seasonal forecasting of the meteorological and oceanographic parameters
at Cochin using autoregressive, sinusoidal and exponentially weighted moving average techniques and testing their accuracy with the observed data for the period 1991-1993. The fifth chapter describes the seasonal cycles of sea level and the driving forces at 16 stations along the Indian subcontinent. It also addresses the observed interannual variability of sea level at 15 stations using available multi-annual data sets. The sixth chapter deals with the problem of coastal trapped waves between Cochin and
Beypore off the Kerala coast using sea level and atmospheric pressure data sets for the year 1977. The seventh and the last chapter contains the summary and conclusions and future outlook based on this study.
Suryakumari, S; Dr.Muraleedharan Nair, S(Cochin University of Science and Technology, August , 2009)
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Abstract:
The present study which is the first of its kind in this region is an
attempt to generate adequate information on the relative abundances, the
seasonal and spatial variations as well as on the source and fate of organic
compounds found associated with the dissolved, particulate and
sedimentary compartments of Chalakudy river system. The study aimed at
investigating variations, the relative proportion of dissolved, particulate and
sedimentary fractions of these materials as well as the pollution extent so as
to be able to comment on the present condition of this river-estuarine
system. This thesis focuses attention on the role of biogeoorganics in modifying the ecological and environmental condition of the dissolved,
particuIate and sediment compartments with their minute variability
subjected to various physical, chemical and biogeochemical processes. A
scheme of study encompassing all these objectives provides the frame work
for the present investigation.
Description:
Department of Chemical
Oceanography,Cochin University of Science
and Technology
Madhu, N V; Gopalakrishnan,T C(Cochin University of Science and Technology, September , 2004)
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Abstract:
The thesis describes the importance of Indian EEZ, definition and the various factors affecting primary production, general account of phytoplankton and its importance in marine ecosystem etc. In review of literature, general oceanography of Arabian Sea and Bay of Bengal and hydrography of eastern Arabian Sea and western Bay of Bengal. It deals with the distribution patterns of primary production, chlorophyll a, phytoplankton composition and particulate organic carbon in the eastern Arabian Sea and western Bay of Bengal during different seasons. Factors that affect primary productivity are irradiance, temperature, stability of the surface waters, nutrients and zooplankton grazing. The differential biological response of eastern Arabian Sea and western Bay of Bengal to monsoonal regimes. A precise estimation on the primary production of the entire EEZ of India on a regional basis and on a seasonal scale would be the only way to achieve any kind of predictive assessment on the fish stock and their sustainable yield. This study mainly envisages the qualitative and quantitative aspects on the magnitude of phytoplankton standing crop and production of organic carbon and their relationship to environmental characteristics during summer monsoon, Inter monsoon and winter monsoon periods in the east and west coasts of the Indian EEZ.This study revealed that the seasonality exerts a great impact on the biological production in the eastern Arabian Sea and western Bay of Bengal. High biological production may be the reason why most of the fish landings are Concentrated in the west coast of India than east coast. The present data on Phytoplankton production rate and the species composition will provide a meaningful ground for evaluations of exploitable renewable resources of the IndianEEZ