Maya L Pai; Dr. A N Balchand; Dr. K V Pramod(Cochin University of Science and Technology, May 12, 2016)
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Abstract:
ANN based long range forecast of Indian summer monsoon rainfall for
the hydrological regions of India using ocean and atmosphere state
parameters with improved accuracy,Trend analysis of SST, sub surface temperature of Indian Ocean and
that of ISMR.
3. Prediction of extreme rainfall events using ANN.
Jayaprakash, N S; Bright Singh, I S(School of Environmental Studies, 2005)
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Abstract:
The main objective of the work undertaken here was to develop an appropriate microbial technology to protect the larvae of M.rosenbergii in hatchery from vibriosis. This technology precisely is consisted of a rapid detection system of vibrios and effective antagonistic probiotics for the management of vibrios. The present work was undertaken with the realizations that to stabilize the production process of commercial hatcheries an appropriate, comprehensive and fool proof technology is required primarily for the rapid detection of Vibrio and subsequently for its management. Nine species of Vibrio have been found to be associated with larvae of M. rosenbergii in hatchery. Haemolytic assay of the Vibrio and Aeromonas on prawn blood agar showed that all isolates of V. alginolyticus and Aeromonas sp., from moribund, necrotized larve were haemolytic and the isolates of V.cholerae, V.splendidus II, V.proteolyticus and V.fluvialis from the larvae obtained from apparently healthy larval rearing systems were non-haemolytic.
Hydrolytic enzymes such as lipase, chitinase and gelatinase were widespread amongst the Vibrio and Aeromonas isolates. Dominance of V.alginolyticus among the isolates from necrotic larvae and the failure in isolating them from rearing water strongly suggest that they infect larvae and multiply in the larval body and cause mortality in the hatchery. The observation suggested that the isolate V. alginolyticus was a pathogen to the larvae of M.rosenbergii. To sum up, through this work, nine species of Vibrio and genus Aeromonas associated with M.rosenbergii larval rearing systems could be isolated and segregated based on the haemolytic activity and the antibodies (PA bs) for use in diagnosis or epidemiological studies could be produced, based on a virulent culture of V.alginolyticus. This could possibly replace the conventional biochemical tests for identification. As prophylaxis to vibriosis, four isolates of Micrococcus spp. and an isolate of Pseudomonas sp. could be obtained which could possibly be used as antagonistic probiotics in the larval rearing system of M.rosenbergii.
Prajith, K K; Dr.Madhusoodana,Kurup B(Cochin University of Science and Technology, December , 2011)
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Abstract:
In India a study conducted by CIFE and CIBA (1997), concluded that
shrimp farming does more good than harm and it is not eco-unfriendly
(Krishnan and Birthal, 2002). Upsurge in coastal aquaculture activity
induced by high profitability is reported to have caused adverse impacts on
coastal ecosystems and social environments (Parthasarathy and Nirmala,
2000). The crustacean farming sector has received criticism for excessive
use of formulated feed containing high protein, of which around 50% gets
accumulated at the pond bottom as unconsumed (Avnimelech, 1999; Hari
et al., 2004, 2006). The wasted feeds undergo the process of degradation
and results in the release of toxic metabolites to the culture system.
Reduction of protein in the feed, manipulation and utilisation of natural
food in the culture system are the remedy for the above problems. But
before reducing the feed protein, it should be confirmed that the feed with
reduced protein is not affecting the growth and health of the cultured
animal. In the present study, biofloc technology is identified as one of the
innovative technologies for ensuring the ecological and environmental
Sustainability and examines the compatibility of BFT for the sustainable
aquaculture of giant prawn, M. rosenbergii. This thesis starts with a general introduction (Chapter-1), a brief review of the most relevant literature (Chapter-2), results of various experiments (Chapter-3-6), summary (Chapter-7) and recommendations and future research perspectives in the field of biofloc based aquaculture (Chapter – 8). The major objectives of this thesis are, to improve the ecological and economical sustainability of prawn farming by the applicationof BFT and to improve the nutrient utilisation in aquaculture systems.
Description:
School of Industrial Fisheries, Cochin University of Science and Technology
Ravi, Divakaran; Dr.Sivasankara Pillai, V N(Cochin University of Science and Technology, January 15, 2002)
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Abstract:
The most common and conventional method for removing turbidity from
water is by coagulating with alum or iron salts, and settling the precipitate in
suitably designed clarifiers followed by filtration. But the sludge produced is
bulky, difficult to dewater and accumulates in the dumping grounds causing
environmental problems. Synthetic polymers such as polyacrylamide and
polyethyleneoxide have been investigated for their ability to remove turbidity.
They overcome many of the disadvantages of conventional methods, but are
cost—effective only when rapid flocculation and reduction in sludge volume are
demanded. Considering the aforementioned situation, it was felt that more easily
available and eco-friendly materials must be developed for removing turbidity
from water. The results of our studies in this direction are presented in this
thesis. The thesis comprises of nine chapters, with a common bibliography at
the end. Chapter 1 gives an introduction to the nature of turbidity and colour
usually present in water. Chapter 2 discusses the nature and availability of the
principal material used in these studies, namely chitosan. Chapters 3 to 8, which
deal with the actual experimental work, are further subdivided into (a)
introduction, (b) materials and methods, (c) results and discussion and (d)
conclusions. Chapter 9 summarises the entire work so as to put the results and
conclusions into proper perspective.
Description:
School
of Environmental Studies, Cochin University of Science and Technology,
Sini, T K; Dr. Mathew, P T(Central Institute of Fisheries Technology, December , 2007)
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Abstract:
The present study aimed at the utlisation of microbial organisms for the
production of good quality chitin and chitosan. The three strains used for the
study were Lactobacillus plantarum, Lactobacililus brevis and Bacillus subtilis.
These strains were selected on the basis of their acid producing ability to reduce
the pH of the fermenting substrates to prevent spoilage and thus caused
demineralisation of the shell. Besides, the proteolytic enzymes in these strains
acted on proteinaceous covering of shrimp and thus caused deprotenisation of
shrimp shell waste. Thus the two processes involved in chitin production can be
affected to certain extent using bacterial fermentation of shrimp shell.Optimization parameters like fermentation period, quantity of inoculum,
type of sugar, concentration of sugar etc. for fermentation with three different
strains were studied. For these, parameters like pH, Total titrable acidity (TTA),
changes in sugar concentration, changes in microbial count, sensory changes
etc. were studied.Fermentation study with Lactobacillus plantarum was continued with 20%
w/v jaggery broth for 15 days. The inoculum prepared yislded a cell
concentration of approximately 108 CFU/ml. In the present study, lactic acid and
dilute hydrochloric acid were used for initial pH adjustment because; without
adjusting the initial pH, it took more than 5 hours for the lactic acid bacteria to
convert glucose to lactic acid and during this delay spoilage occurred due to
putrefying enzymes active at neutral or higher pH. During the fermentation study,
pH first decreased in correspondence with increase in TTA values. This showed
a clear indication of acid production by the strain. This trend continued till their
proteolytic activity showed an increasing trend. When the available sugar source
started depleting, proteolytic activity also decreased and pH increased. This was
clearly reflected in the sensory evaluation results. Lactic acid treated samples
showed greater extent of demineralization and deprotenisation at the end of
fermentation study than hydrochloric acid treated samples. It can be due to the
effect of strong hydrochloric acid on the initial microbial count, which directly
affects the fermentation process. At the end of fermentation, about 76.5% of ash was removed in lactic acid treated samples and 71.8% in hydrochloric acid
treated samples; 72.8% of proteins in lactic acid treated samples and 70.6% in
hydrochloric acid treated samples.The residual protein and ash in the fermented residue were reduced to
permissible limit by treatment with 0.8N HCI and 1M NaOH. Characteristics of
chitin like chitin content, ash content, protein content, % of N- acetylation etc.
were studied. Quality characteristics like viscosity, degree of deacetylation and
molecular weight of chitosan prepared were also compared. The chitosan
samples prepared from lactic acid treated showed high viscosity than HCI treated
samples. But degree of deacetylation is more in HCI treated samples than lactic
acid treated ones. Characteristics of protein liquor obtained like its biogenic
composition, amino acid composition, total volatile base nitrogen, alpha amino
nitrogen etc. also were studied to find out its suitability as animal feed
supplement.Optimization of fermentation parameters for Lactobacillus brevis
fermentation study was also conducted and parameters were standardized. Then
detailed fermentation study was done in 20%wlv jaggery broth for 17 days. Also
the effect of two different acid treatments (mild HCI and lactic acid) used for initial
pH adjustment on chitin production were also studied. In this study also trend of
changes in pH. changes in sugar concentration ,microbial count changes were
similar to Lactobacillus plantarum studies. At the end of fermentation, residual
protein in the samples were only 32.48% in HCI treated samples and 31.85% in
lactic acid treated samples. The residual ash content was about 33.68% in HCI
treated ones and 32.52% in lactic acid treated ones. The fermented residue was
converted to chitin with good characteristics by treatment with 1.2MNaOH and
1NHCI.Characteristics of chitin samples prepared were studied and extent of Nacetylation
was about 84% in HCI treated chitin and 85%in lactic acid treated
ones assessed from FTIR spectrum. Chitosan was prepared from these samples
by usual chemical method and its extent of solubility, degree of deacetylation,
viscosity and molecular weight etc were studied. The values of viscosity and
molecular weight of the samples prepared were comparatively less than the
chitosan prepared by Lactobacillus plantarum fermentation. Characteristics of protein liquor obtained were analyzed to determine its quality and is suitability as
animal feed supplement.Another strain used for the study was Bacillus subtilis and fermentation
was carried out in 20%w/v jaggery broth for 15 days. It was found that Bacillus
subtilis was more efficient than other Lactobacillus species for deprotenisation
and demineralization. This was mainly due to the difference in the proteolytic
nature of the strains. About 84% of protein and 72% of ash were removed at the
end of fermentation. Considering the statistical significance (P<O.05) in the
extent of demineralization and deproteinisation, we have taken 0.8N HCI for the
demineralization study and 0.6M NaOH for deprotenisation study. Properties of
chitin and chitosan prepared were analyzed and studied.
Sony, George; Dr.V P N Nampoori(Cochin University of Science & Technology, September , 2011)
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Abstract:
The present thesis report the results obtained from the studies carried out on the
laser blow off plasma (LBO) from LiF-C (Lithium Fluoride with Carbon) thin film
target, which is of particular importance in Tokamak plasma diagnostics. Keeping
in view of its significance, plasma generated by the irradiation of thin film target by
nanosecond laser pulses from an Nd:YAG laser over the thin film target has been
characterized by fast photography using intensified CCD. In comparison to other
diagnostic techniques, imaging studies provide better understanding of plasma
geometry (size, shape, divergence etc) and structural formations inside the plume
during different stages of expansion.
Description:
International School of Photonics,Cochin University of Science and Technology
Shalin Saleem; Dr.Sanil Kumar, K V(Cochin University Of Science And Technology, October 16, 2012)
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Abstract:
Satellite remote sensing is being effectively used in monitoring the ocean
surface and its overlying atmosphere. Technical growth in the field of satellite sensors
has made satellite measurement an inevitable part of oceanographic and atmospheric
research. Among the ocean observing sensors, ocean colour sensors make use of
visible band of electromagnetic spectrum (shorter wavelength). The use of shorter
wavelength ensures fine spatial resolution of these parameters to depict oceanographic
and atmospheric characteristics of any region having significant spaio-temporal
variability.
Off the southwest coast of India is such an area showing very significant
spatio-temporal oceanographic and atmospheric variability due to the seasonally
reversing surface winds and currents. Consequently, the region is enriched with
features like upwelling, sinking, eddies, fronts, etc. Among them, upwelling brings
nutrient-rich waters from subsurface layers to surface layers. During this process
primary production enhances, which is measured in ocean colour sensors as high
values of Chl a. Vertical attenuation depth of incident solar radiation (Kd) and Aerosol
Optical Depth (AOD) are another two parameters provided by ocean colour sensors.
Kd is also susceptible to undergo significant seasonal variability due to the changes in
the content of Chl a in the water column. Moreover, Kd is affected by sediment
transport in the upper layers as the region experiences land drainage resulting from
copious rainfall. The wide range of variability of wind speed and direction may also
influence the aerosol source / transport and consequently AOD.
The present doctoral thesis concentrates on the utility of Chl a, Kd and AODprovided by satellite ocean colour sensors to understand oceanographic and
atmospheric variability off the southwest coast of India. The thesis is divided into six
Chapters with further subdivisions
Description:
faculty
of Marine Sciences,Cochin University of Science and Technology
Mary, Alexander; Dr. Eby Thomas, Thachil(Cochin University of Science & Technology, April , 2008)
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Abstract:
This research project explores the utilization of cardanol in various capacities for
rubber processing. Cardanol is a phenol with a long side chain in the meta position
of the benzene ring. It is obtained by the vacuum distillation of cashew Hut shell
liquid (CNSL) which is a cheap agro-byproduct. In this study, the plasticizer property
of cardanol was investigated in silica filled and HAF black filled NR, NBR, EPDM
and CR by comparing cure characteristics and mechanical properties of vulcanizates
containing conventional plasticizer with those containing cardanol as plasticizer. The
co-activator, antioxidant and accelerator properties were investigated in gum samples
of NR, NBR, EPDM and CR by comparing the properties of vulcanizates which
contain conventional co-activator, antioxidant and accelerator with those in which
each of them was replaced by cardanol. The general effectiveness of cardanol was
investigated by determination of cure time , measurement of physical and
mechanical properties, ageing studies, crosslink density, extractability, FTIR spectra,
TGA etc.The results show that cardanol can be a substitute for aromatic oil in both silica filled
and HAF black filled NR. Again, it can replace dioctyl phthalate in both silica filled
and HAF black filled NBR. Similarly, cardanol Can replace naphthenic oil in silica
filled as well as HAF black filled EPDM and CR. The cure characteristics and
mechanical properties are comparable in all the eight cases. The co-activator
property of cardanol is comparable to stearic acid in all the four rubbers. The cure
characteristics and mechanical properties in this case are also comparable. The
antioxidant ,property of cardanol is comparable to TQ in all the four rubbers. The
antioxidant property of cardanol is comparable to TQ in all the four case of NBR and
EPDM.The
accelerator property of cardarlol is comparable with CBS in the case of NBR and
EPDM. No accelerator property is observed in the case of NR. The accelerator
property of cardanol in CR is not negligible when compared with TMTD.
Description:
Department of Polymer Science and Rubber Technology,
Cochin University of Science and Technology
Anupam,Chandran R; Dr.Aanandan, C K(Cochin University of Science and Technology, June , 2007)
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Abstract:
This thesis presents the Radar Cross Section measurements of different geometric structures such as flat plate,cylinder, corner reflector and circular cone loaded with fractal based metallo dielectric structures.Use of different fractal geometris,metallizations of different shapes as well as the frequency tanability is investigated for TE and TM polarization of the incident electromagnetic field.Application of fractal based metallo-dielectric structures results in RCS reduction over a wide range of frequency bands.RCS enhancement of dihedral corner is observed at certain acute and obtuse corner angles.The experimental results are validated using electromagnetic simulation softwares.
Description:
Department of Electronics,
Cochin University of Science and Technology