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
George, V C; Dr.Samuel, C T(Cochin University Of Science And Technology, September 14, 1991)
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Abstract:
In the present study. extensive investigations were
carried out on various factors affecting the selectivity of
prawn gill nets with reference to material, mesh size,
coefficient of hanging secolouration. Effect of tidal current
on fishing height of prawn gill net and seasonal variation of
catch during the course of these investigations were also
studied.
Description:
Department of Industrial Fisheries. Cochin
University of science and Technology
Aloysius, R P; Dr.Syamaprasad,U(Cochin University Of Science And Technology, December 30, 2002)
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Abstract:
The application vistas of superconductors have widened very
much since the discovery of high TC superconductors (HTS) as many of the
applications can be realised at 77 K rather than going down to 4.2 K, the
liquid He temperature. One such application is the HTS current lead which is
used to connect a superconducting system with a room temperature power
source. Minimising heat leak to the cryogenic environment is the main
advantage of introducing current leads into superconducting systems. The
properties of HTSS likes zero resistance (avoiding joule heating) and very
low thermal conductivity (minimized conductive heat transfer) make them
ideal candidates to be used as current leads. There are two forms of HTS
current leads. (i) bulk form (tube or rod) prepared either from YBCO or
BSCCO and (ii) tape form prepared from Bi-2223 multifilamentary tapes.
The tape form of current leads has many advantages with respect to the
mechanical and thermal stability related criteria. Crucial information on
various aspects of HTS current lead development are not available in the
literature as those are kept proprietary by various companies around the
world. The present work has been undertaken to tailor the properties of
multifilamentary tapes for the current lead application and to optimise the
processing parameters of the same for enhanced critical current density and
field tolerance. Also it is the aim of the present investigation is to prepare
prototype current leads engineered for operation in conduction cooled mode
and test them for operational stability
Description:
Council Of Scientific And Industrial Research [Csir]
Regional Research Laboratory
Trivandrum
Claramma, N M; Dr.Mathew, N M(Cochin University of Science and Technology, April 22, 1997)
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Abstract:
Systematic investigations on prevulcanization of NR latex with
special reference to the influence of storage of latex and after-treatments
of films, have been carried out. The other aspects studied include the
effect of temperature on sulphur prevulcanization, the extent of crosslinking,
tensile properties, stress relaxation characteristics, water absorption and
leaching characteristics of prevulcanizcd latex films
Description:
Rubber Research Institute of India
Rubber Board, Kottayam
Subramaniyan, S; Dr. Prema, P(Regional Research Laboratory, February , 2000)
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Abstract:
Xylanases with hydrolytic activity on xylan, one of the hemicellulosic
materials present in plant cell walls, have been identified long back and the
applicability of this enzyme is constantly growing. All these applications
especially the pulp and paper industries require novel enzymes. There has
been lot of documentation on microbial xylanases, however, none meeting all
the required characteristics. The characters being sought are: higher
production, higher pH and temperature optima, good stabilities under these
conditions and finally the low associated cellulase and protease production.
The present study analyses various facets of xylanase biotechnology giving
emphasis on bacterial xylanases. Fungal xylanases are having problems like
low pH values for both enzyme activity and growth. Moreover, the associated
production of cellulases at significant levels make fungal xylanases less
suitable for application in paper and pulp industries.Bacillus SSP-34 selected from 200 isolates was clearly having xylan
catabolizing nature distinct from earlier reports. The stabilities at higher
temperatures and pH values along with the optimum conditions for pH and
temperature is rendering Bacillus SSP-34 xylanase more suitable than many of
the previous reports for application in pulp and paper industries.Bacillus SSP-34 is an alkalophilic thertmotolerant bacteria which
under optimal cultural conditions as mentioned earlier, can produce 2.5 times
more xylanase than the basal medium.The 0.5% xylan concentration in the medium was found to the best
carbon source resulting in 366 IU/ml of xylanase activity. This induction was
subjected to catabolite repression by glucose. Xylose was a good inducer for
xylanase production. The combination of yeast extract and peptone selected
from several nitrogen sources resulted in the highest enzyme production
(379+-0.2 IU/ml) at the optimum final concentration of 0.5%. All the cultural
and nutritional parameters were compiled and comparative study showed that the modified medium resulted in xylanase activity of 506 IU/ml, 5 folds higher than the basal medium.The novel combination of purification techniques like ultrafiltraton,
ammonium sulphate fractionation, DEAE Sepharose anion exchange
chromatography, CM Sephadex cation exchange chromatography and Gel
permeation chromatography resulted in the purified xylanase having a specific
activity of 1723 U/mg protein with 33.3% yield. The enzyme was having a
molecular weight of 20-22 kDa. The Km of the purified xylanase was 6.5 mg
of oat spelts xylan per ml and Vmax 1233 µ mol/min/mg protein.Bacillus SSP-34 xylanase resulted in the ISO brightness increase from
41.1% to 48.5%. The hydrolytic nature of the xylanase was in the endo-form.Thus the organism Bacillus SSP-34 was having interesting
biotechnological and physiological aspects. The SSP-34 xylanase having
desired characters seems to be suited for application in paper and pulp
industries.
Jayadevan, A P; Dr. Ramesh Babu, T(Cochin University of Science and Technology, February , 2005)
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Abstract:
In this thesis quark-antiquark bound states are considered using a relativistic two-body
equation for Dirac particles. The mass spectrum of mesons includes bound states
involving two heavy quarks or one heavy and one light quark. In order to analyse these
states within a unified formalism, it is desirable to have a two-fermion equation that limits
to one body Dirac equation with a static interaction for the light quark when the other
particle's mass tends to infinity. A suitable two-body equation has been developed by Mandelzweig
and Wallace. This equation is solved in momentum space and is used to describe
the complete spectrum of mesons. The potential used in this work contains a short range
one-gluon exchange interaction and a long range linear confining and constant potential
terms. This model is used to investigate the decay processes of heavy mesons. Semileptonic
decays are more tractable since there is no final state interactions between the leptons
and hadrons that would otherwise complicate the situation. Studies on B and D meson
decays are helpful to understand the nonperturbative strong interactions of heavy mesons,
which in turn is useful to extract the details of weak interaction process. Calculation of
form factors of these semileptonic decays of pseudo scalar mesons are also presented.
Description:
Department of Physics,
Cochin University of Science and Technology