Jossia, Joseph K; Dr. Balchand, A N(Cochin University of Science and Technology, October , 2011)
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Abstract:
The present study on upper ocean responses to atmospheric forcing (associated with
cyclone passage) in North Indian Ocean revealed significant variability between AS and
BoB. The analysis of cyclone frequency during 1947 to 2006 exhibited lesser frequency
of cyclones in AS than that of BoB. The analysis also revealed significant reduction in
cyclone frequency after the year 1976 with substantial reduction during monsoon season.
The long term SST data at selected points in AS and BoB could not reveal any relation
with reduction in cyclone frequency. However the SLP at same locations exhibited
considerable increase during mid 1970’s, which could have contributed to the observed
reduction in cyclone frequency after the year 1976.The response in waves during cyclone passage exhibited significant asymmetry on either
side of the track in AS and BoB and the response is observed at 100’s of kilometers away
from the track. The significant clockwise rotation in wave direction is observed on the
right side of the track starting from near the track to far away locations, which existed for
a longer duration. However, the anticlockwise rotation in wave direction is observed over
a shorter distance on the left side of the track and dissipated immediately.Inertial oscillation is observed in surface current and in the mixed layer temperature
associated with cyclone passage, which revealed the role of relative location(s) on either
side of the track. The inertial peak closer to the local inertial period indicates maximum
transfer of energy during the cyclone passage in both AS and BoB. The absence of strong
inertial oscillation even with clockwise rotation in surface current and wind indicates the
dominant role of duration of strong wind in generating inertial oscillation.The oceanic response associated with cyclone passage reveal the variable response(s)
which depends on cyclone intensity, the proximity to track and cyclone translation speed.
It is observed that resonance with wind generates higher response in surface current,
wave and SST on the right side of the track and it lasts for a longer duration. The
maximum oceanic response is observed at a few kilometers away on right side of the
track. However lesser rightward bias in the location of maximum cooling is observed for
cyclones with low cyclone translation speed. The response on the left side of the track is
less and is limited over a shorter distance and dissipates immediately. It is observed that
the ocean response, in general, increases with intensity of cyclones. However the
differential cooling produced by the same intensity cyclones in AS and in BoB indicates
the dominant role of low cyclone translation speed in oceanic response.The surface cooling exhibited strikingly differential responses between AS and BoB. The
TMI-SST and buoy observations exhibited significant cooling for a longer duration in AS
compared to that of BoB. The spatial extent of cooling is also much higher in AS than
that of BoB. The wide spread cooling associated with cyclone passage in AS indicates
the dominant role of thermal structure in oceanic response in AS than that of BoB.
Description:
Department of Physical Oceanography,
Cochin University of Science and Technology
Reghunath, A T; Dr.Nampoori,V P N(Cochin University of Science And Technology, November , 1987)
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Abstract:
The central theme of the work presented in this thesis is a careful investigation of the factors influencing the attenuation of laser beam through sea water. The thesis presents a detailed report of the work done by the author on the attenuation studies in sea water and on laser propagation through a turbulent medium. The thesis contains six chapters which are more or less self-contained with separate abstracts and references. The first chapter is divided into two parts. The first part introduces the subject of laser propagation through sea water. It includes a brief
description of optical properties of sea water followed by a review of the earlier works on attenuation studies in water. The second part gives the theoretical background of the problem
of laser propagation through a turbulent medium.
Description:
Department of physics, Cochin University of Science And Technology
Kalpana, K V; Dr.James, P S B R(Cochin University of Science and Technology, 1999)
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Abstract:
Metapenaeus dobsoni (Miers) is the most abundant species
along the coast of Kerala. It is cultured extensively by adoption of
traditional farming practices. The geographical location and water source
determines the seasonal and annual environmental fluctuations the
prawn farming systems experiences. The life cycle of the shrimp includes
its migration to the coastal deeper waters for spawning and the immigration
of larvae to the estuaries for growth. The survival of the species in such
complex ecosystems is thus critical to its life cycle. The animal adapts itself to
different environments through a physiological process known as osmoregulation.
The present study on osmoregulation in the penaeid prawn
Metapenaeus dobsoni was thus undertaken to understand the mechanism
adopted by this species to survive in different environments. A
number of experimental work have been conducted to understand the
effect of salinity on the internal variations. However the effect of the
complex environmental conditions as existent in nature on the osmotic
variations in this species has not been dealt with in any of the earlier studies.
Chandra Prabha, A C; Dr.Sharma,G S(Cochin University of Science and Technology, October , 1986)
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Abstract:
The thesis is divided into six chapters, with Further subdivisions.’ Chapter one has two sections. Section one deals with a general introduction, and section two,with the material and treatment of data For the present investigation. The second chapter concerns with the distribution of oxyty in the oxygen minimum layer and its topography during the southwest and northeast monsoons. The distribution of oxyty at various isanosteric surfaces within which the oxygen minimum layer lies during southwest and northeast monsoons and their topographies Form chapter three. In the fourth chapter the Flow pattern and its influence on the oxygen minimum layer are discussed. The fifth chapter presents the scatter diagrams of oxyty against temperature at the various isanosteric surfaces. The sixth chapter summarises the results of the investigation and presents the conclusions drawn therefrom
Description:
School of Marine
Science, Cochin
University of Science and Technology
Rajesh, K M; Dr.Sugunan, S(Cochin University of Science and Technology, May , 2011)
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Abstract:
The present work aims to prepare visible light responsive anion doped titania via sol-gel precipitation method.The prepared catalysts were characterized by various techniques.The photocatalytic abilities of the prepared catalysts were measured by the degradation of dyes,pesticides,hydrogen production through water splitting reaction and antibacterial study.We also compared the activities of prepared catalysts with pure titania prepared in the laboratory and one of the commercial anatase titania samples.
Description:
Dept.of Applied Chemistry,Cochin University of Science and Technology
Manzur Ali, P P; Dr.Elyas, K K(Cochin University of Science and Technology, December 19, 2012)
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Abstract:
Protease inhibitors are found abundantly in numerous plants, animals and microorganisms, owing their significance to their application in the study of enzyme structures, reaction mechanisms and also their utilization in pharmacology and agriculture. They are (synthetic/natural) substances that act directly on
proteases to lower the catalytic rate. Although most of these inhibitory proteins are directed against serine proteases, some target cysteine, aspartyl or metalloproteases (Bode and Huber, 1992). Protease inhibitors are essential for regulating the activity of their corresponding proteases and play key regulatory roles in many biological processes. Applications of protease inhibitors are intimately connected to the proteases they inhibit; an overview of proteases with the modes of regulation of their proteolytic activity is discussed
Description:
Department of Biotechnology, Cochin University of Science and Technology
Gopinathan,C P; Dr.Ramachandran Nair,P V(Cochin University of Science and Technology, December , 1981)
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Abstract:
This thesis deals with the results oi’
investigations on phytoplankton productivity and related
aspects conducted in various ecoaystms such as estuarine,
inshore and oceanic enviroments and certain special
ecosytans including the pu.-awn culture fields and associated
many-eves, mud bank and the seas around the Andaman-Nicobar
Islands. This study also includes the qualitative and
quantitative variations of phytoplankton production, their
seasonal abundance, factors controlling the same and the
magnitude of the potential resources derived 1!:-om it
Jacob,George; Dr.Kurian, C V(Cochin University of Science and Technology, April , 1977)
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Abstract:
Planktonic ostracod of the Indian Ocean have not been studied in detail although extensive studies have been made on them from other oceans, particularly Atlantic. with this
view, the present study was undertaken, to throw; some light on the systematics and distribution oi’ planktonic ostracods in this region, This study provides iniormation regarding the distribution or each species in the Northern Indian Ocean, specially in the Bay of Bengal which is the least explored, as far as planlctunio ostracods are concerned. It may also furnish us with the data regarding the nature of ostracod production in this area, which directly reflects on the total
productivity as they play an important role in the rapid recycling or organic substances, iaecal pellets and even flocculants In the present study the main objectives are; (1) Proper detemination of the species or planktonic Ostraooda that occur in the area or investigation, (2) to explain the pattern oi’ distribution, (3) to estimate their abundance and to some extent seasonal variation, and (4) to correlate their distribution with the physics-chemical factors of the environment
Description:
Indian ocean biological center
national institute of oceanography
regional centre
Mercy, Thomas; Dr.Damodaran,R(Cochin University Of Science And Technology, January , 1984)
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Abstract:
True crabs are the most fascinating group of
organisms among the decapod crustaceans. Great importance
is attached at present to the increased exploitation of
these animals and therefore there is great scope for
further development of their fishery. They have a
broad and hard carapace, massive chelate legs, bent
abdomen and exhibit high degree of adaptation to the
environment. They show pelagic, benthic, intertidal,
burrowing and terrestrial modes of life. Their commensal
association with other invertebrates, their breeding
behaviour and life history are of great interest to
biologists. More than six hundred species of crabs are
known to occur in Indian waters and among them
about eight species form a regular fishery along the
entire stretch of peninsular India (Rao §§_al., 1973)
round the year. Crab fishery in India is fast developing
and there is vast scope for them as there are many more
potential species. Among the various crustacean diets,
crabs are celebrated for deliciousness and for nutritional
richness. In recent days, crab food items have become
more popular and gained global reception. These resources
can also be augmented further by culturing them in ponds
in the future. Information on biology and ecology of
constituent species go a long way not only in effective
exploitation and regulation of the respective fishery
resources but also helps in evolving a suitable gear
for their capture. Information collected on the
national level in various aspects as reproduction, growth
rate, larval development, parasites, diseases, nutritive
values etc. will be of help in evolving a national
policy for the effective utilisation and conservation
of this resource. They also provide the baseline information
for undertaking any purposeful and meaningful
culture activities. Information on the various aspects
mentioned above is very much restricted in true crabs
and hence the present study
Description:
School Of Marine Sciences
Cochin University Of Science And Technology
George,K E; Dr.Joseph,Francis D(Cochin University of Science And Technology, March , 1987)
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Abstract:
The study is undertaken on PVC blends because of their all-round importance-One of the most prominent needs of PVC in application end-use is permanent plasticizationlo. Butadiene-acrylonitrile rubber (NBR) has been utilized as permanent plasticizer for PVC since the 1940s for wire and cable insulation, food contact, and pondliners used for oil containment23'24. Also plasticized PVC has been added to vulcanizable nitrile rubber, to yield improved ozone, thermal ageing, and chemical resistance resulting in applications including fuel hose covers, gaskets, conveyor belt covers, and printing roll covers. This blend is miscible in the range of 23 to 45 per cent acrylonitrile content in the butadiene-acrylqnitrile copolymerzs. The first phase of the study was directed towards modification blends. These blends, in addition to the polymers, require
a host of additives like curatives for the NBR phase and stabilizers for the PVC phase26of the existing PVC blends, especially NBR/PVC. The second phase of the study was directed towards
the development of novel PVC based blends. Chloroprene rubber (polychloroprene) (CR) is structurally similar to PVC and hence is likely to form successful blends with PVC32.
Description:
Department of polymer science
& rubber technology,
Cochin University of Science And Technology
Shanti,Avirah A; Dr.Rani,Joseph(Cochin University of Science and Technology, March 20, 1995)
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Abstract:
The primary aim of this work has been to prepare efficient and cost effective polymer bound antioxidants by direct’ attachment of conventional antioxidants to a modified polymer. Due to the importance and easy availability of natural rubber in Kerala, it is proposed to make use of low molecular weight natural rubber as the polymer substrate for binding the antioxidant in most cases. The molecular weight of such low molecular weight natural rubber can be easily manipulated by varying the time of mastication, UV—irradiation etc. Further, the bound antioxidant may also get vulcanized during the vulcanization of the elastomer to which it is added, making the antioxidant non—volatile and non extractable. Several methods are proposed to be investigated for attaching the antioxidant to the low molecular weight natural rubber such as modified Friedel-Craft's alkylation reaction, binding during UV—irradiation, binding during aggressive mastication etc. The efficiency of such rubber bound antioxidants is proposed to be compared with that of conventional antioxidants in terms of volatility, extractability in solvents, ageing resistance etc. Naturally occuring antioxidants such as cardanol, are also proposed to be modified by binding them to low molecular weight natural rubber. The study is undertaken with the intention of generating a class of bound antioxidants which can be used in elastomers for aggressive and long term application.
Description:
Department of Polymer Science and Rubber Technology, Cochin University of
Science and Technology
Ravindran, T; Dr.Joseph,Francis D(Cochin University of Science And Technology, March , 1989)
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Abstract:
In the present study, the photochemical
depolymerisation of NR in toluene, in presence of
H202 and a homogenizing solvent (Methanol/Tetrahydro—
furan) so as to get hydroxyl terminated liquid natural
rubber (HTNR) has been carried out. The copolymeri—
sation of this product with butane 1,4 diol and toluene
2,4 diisocyanate in presence of a catalyst, dibutyl tin
dilaurate, to produce polyurethanes with HTNR soft segments
is also reported. The preparation of block
copolymers based on poly(ethylene oxide) with varying
molecular weights and HTNR are also discussed along with
a detailed study on their thermal and mechanical properties
Description:
Department of Polymer science and Rubber technology, Cochin University of Science And Technology