Latex waste like glove waste was effectively modified using a new reclaiming
agent, thiocarbanilide. This modified waste was blended with linear low-density
polyethylene (LLDPE) to develop a novel thermoplastic elastomer. Both uncrosslinked
and dynamically crosslinked blends were prepared and their properties
were studied. The results were found to be comparable to those of conventional
thermoplastic elastomers.
Ivy, Mathew; Dr.Joseph,Francis D(Cochin University Of Science And Technology, August 20, 1992)
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Abstract:
Thermoplastic elastomers are a relatively new
class of materials which compete with thermoset rubbers in
some areas and thermoplastic materials in other areas. The
main thrust of the present investigation is a comparative
study’ on commercially .available triblock. styrene thermoplastic
elastomers and those derived from blends of
acrylonitrile-butadiene rubber and poly(vinyl chloride).
The styrene—based thermoplastic elastomers are gaining
acceptance as a replacement for both natural and synthetic
rubber‘ in many‘ applications. TPEs based on blends of
elastomers and plastics ix: the fastest growing segment of
the broad class of thermoplastic elastomers. Broad
applicability and simple technology of production are the
attractive features of this class of TPES. NBR/PVC thermoplastic
elastomers were selected for this investigation due
to the versatility of PVC, its number one position, low
cost. ability to Ina compounded into various flexible and
rigid form with good physical and chemical and weathering
properties etc., which will be passed over to PVC blends
especially NBR/PVC blends which are known to form miscible
systems
Description:
Department of Polymer Science and Rubber
Technology, Cochin University of Science and Technology
Lizen, Mathews; Dr.Chandramohanakumar, N(Department of Chemical Oceanography, School of Marine Sciences, 2000)
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Abstract:
In the present study the nutrient dynamics and fertility of Kuttanad waters is addressed. Kuttanad represent a wetland system with considerable agricultural activities. The hydrographical features of the Kuttanad waters are controlled by discharges from Manimala, Meenachil, Pamba, Achencoil and Muvattupuzha rivers and also by tidal intrusions of saline waters from Cochin backwaters during summers. The fertility of these water bodies were significantly high and supported good agricultural production. Kuttanad water forms the southern part of this aquatic systems and is considered as the most productive zones. As a part of the management scheme for a higher agricultural activity, the Thannermukkam bund was constructed to block and regulate the intrusion of saline water. The increased use of artificial fertilizers along with stagnant character of the water body in this area has resulted in sharp decline in the water quality, productivity and aquatic resources.
Lizen, Mathews; Dr.Chandramohanakumar, N(Cochin University of Science and Technology, January , 2000)
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Abstract:
In the present study the nutrient dynamics and fertility of Kuttanad waters is addressed. Kuttanad represent a wetland system with considerable agricultural activities. The hydrographical features of the Kuttanad waters are controlled by discharges from Manimala, Meenachil, Pamba, Achencoil and Muvattupuzha rivers and also by tidal intrusions of saline waters from Cochin backwaters during summers. The fertility of these water bodies were significantly high and supported good agricultural production. Kuttanad water forms the southern part of this aquatic systems and is considered as the most productive zones. As a part of the management scheme for a higher agricultural activity, the Thannermukkam bund was constructed to block and regulate the intrusion of saline water. The increased use of artificial fertilizers along with stagnant character of the water body in this area has resulted in sharp decline in the water quality, productivity and aquatic resources.
Prasanth A, Pillai; Dr.Mohan Kumar, K(Cochin University of Science & Technology, October , 2008)
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Abstract:
The present study illustrates the biennial oscillation in different ocean-atmosphere
parameters associated with interannual variability of Indian summer monsoon rainfall.It also accounts the role of different processes like ENSO, IOD, QBO and ISO in the monsoon variability during the TBO years.
Description:
Department of Atmospheric Sciences,
Cochin University of Science and Technology
Muthu Velan, B; Dr. Krishnamurthy, Chennubhotla, V S(Cochin University of Science and Technology, June , 1994)
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Abstract:
The importance of marine algae, often referred to
as seaweeds, has been felt over a long time and is
appreciated more and more in modern times. The economic
value of marine algae is understood both indirectly and
directly. The indirect benefit is due to the role of marine
phytoplankton as well as the benthic macrophyte biomass
along the shore and in the continental shelf, in primary
production of the sea. Direct benefit includes the use of
marine algae as food, feed, fertilizer and as source of
various products of commercial importance such as agar and
alginic acid. Hence to understand the potential resources of
seaweeds, their distribution, density, standing crop and
interrelated environmental parameters, a detailed study
(survey and ecological work) was carried out for a period of
20 months from August 1988 to March 1990 in South Andaman,
North Andaman, Middle Andaman, Havelock, Neil, Car Nicobar,
Terassa, Chowra and Bumpoka islands. However in South
Andaman, data were collected from five fixed stations
fortnightly during this period for the purpose of modelling
and system analysis.
Rekha R mallia; Dr.Prathapan, S(Cochin University of Science and Technology, December , 2007)
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Abstract:
The thesis entitled ‘Studies on the Solvent Dependence in the
Reaction of a Few (Anthracen-9-yl)methylamines and Sulfanes with
Reactive Acetylenes’ is divided into six chapters. ln Chapter l a general
survey of electron transfer reactions, Diels-Alder reactions and Michael-type
additions is presented. A detailed discussion on the synthesis of several
(anthracen-9-yl)methylamines is presented in Chapter 2. In Chapter 3,
results of preliminary photophysical studies on a few (anthracen-9yl)
methylamines are compiled. A detailed discussion on extensive
examination of dependence in the reaction of (anthracen-9-yl)methylamines
with reactive acetylenes is presented Chapter 4. Details on the synthesis and
reaction of a few (anthracen-9-yl)methylsulfanes with DMAD are described in
Chapter 5.
The thesis report results obtained from a detailed analysis of the fluctuations of the rheological parameters viz. shear and normal stresses, simulated by means of the Stokesian Dynamics method, of a macroscopically homogeneous sheared suspension of neutrally buoyant non-Brownian suspension of identical spheres in the Couette gap between two parallel walls in the limit of vanishingly small Reynolds numbers using the tools of non-linear dynamics and chaos theory for a range of particle concentration and Couette gaps. The thesis used the tools of nonlinear dynamics and chaos theory viz. average mutual information, space-time separation plots, visual recurrence analysis, principal component analysis, false nearest-neighbor technique, correlation integrals, computation of Lyapunov exponents for a range of area fraction of particles and for different Couette gaps.
The thesis observed that one stress component can be predicted using another stress component at the same area fraction. This implies a type of synchronization of one stress component with another stress component. This finding suggests us to further analysis of the synchronization of stress components with another stress component at the same or different area fraction of particles. The different model equations of stress components for different area fraction of particles hints at the possible existence a general formula for stress fluctuations with area fraction of particle as a parameter
Malini, K A; Dr.Anantharaman, M R(Cochin University of Science and Technology, May 30, 2001)
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Abstract:
This thesis mainly deals with the preparation and studies on magnetic composites based on spinel ferrites prepared both chemically and mechanically. Rubber ferrite composites (RFC) are chosen because of their mouldability and flexibility and the ease with which the dielectric and magnetic properties can be manipulated to make them as useful devices. Natural rubber is chosen as the
Matrix because of its local availability and possible value addition. Moreover, NR represents a typical unsaturated nonpolar matrix. The work can be thought of as two parts. Part l concentrates on the preparation and characterization of nanocomposites based on y-Fe203. Part 2 deals with the preparation and characterization of RFCs containing Nickel zinc ferrit In the present study magnetic nanocomposites have been prepared by ionexchange method and the preparation conditions have been optimized. The insitu incorporation of the magnetic component is carried out chemically. This method is selected as it is the easiest and simplest method for preparation of nanocomposite. Nanocomposite samples thus prepared were studied using VSM, Mossbauer spectroscopy, Iron content estimation, and ESR spectroscopy. For the preparation of RFCs, the filler material namely nickel zinc ferrite having the general formula Ni)_xZnxFez04, where x varies from 0 to 1 in steps of 0.2 have been prepared by the conventional ceramic techniques. The system of Nil_xZn"Fe204 is chosen because of their excellent high frequency characteristics. After characterization they are incorporated into the polymer matrix of natural rubber by mechanical method. The incorporation is done according to a specific recipe and for various Loadings of magnetic fillers and also for all compositions. The cure characteristics, magnetic properties and dielectric properties of these composites are evaluated. The ac electrical conductivity of both ceramic nickel zinc ferrites and rubber ferrite composites are also calculated using a simple relation. The results are correlated.
Description:
Physics Department,
Cochin UniversIty of Science & Technology
Annam,Chacko P; Dr.Madhavan Pillai, P(Cochin University of Science and Technology, May , 1987)
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Abstract:
Strychnine, the major alkaloid present in Strychnos nuxvomica seeds has been reported to stimulate the entire central nervous system with preference for the spinal cord. It is a powerful convulsant and because of this property, it is an important pharmacological tool as it plays a unique role as an inhibitor of post synaptic inhibitory impulses. It is useful to study inhibitory
transmitter and receptor types. However, because of its extreme toxicity, strychnine does not have any therapeutic application in the Western system of medicine. The present work was undertaken with a view to obtaining strychnine derivatives having CNS stimulating properties but with sufficiently low toxicity so that they may eventually find some application in medicine. As strychnine is isolated from the locally available strychnos Nugvomica seeds, it’s possible utilization in therapeutics will have considerable commercial significance. This work tries to provide several new compounds which are significantly less toxic than strychnine and its N—oxide as shown from the pharmacological Studio As they also possessed CNS stimulating properties, they are well suited for further screening to assess their potential as valuable therapeutic agents.
Description:
Department of Applied Chemistry, Cochin University
of Science and Technology
Vidya,Raman; Prathapan,S(Department of Applied Chemistry ,Faculty of Science, 2004)
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Abstract:
The thesis entitled studies on the synthesis and transformations of a few 2(3H)- and 3(2H)- furanones. Furanones represent an interesting class of heterocyclic compounds, which constitute the central ring system of many natural products. The derivatives of furan is divided, depending on their structure 2(3H)-furanones(I), 2(5H)-furanones(II), and 3(2H)-furanones(III). Systems I&II are unsatured gama lactones known as ‘butenolides’. Compounds of this type also known as ‘crotonolactones’ based on the parent crotonic acid. In conclusion a number of 2(3H)-and 3(2H)- furanones were synthesized from dibenzoylalkene precursors and were characterized on the basis of spectral analytical and X-ray data. On direct irradiation 3,3-bis(4-chloropheneyl)-5-aryl-3H-furan -2-ones underwent decarbonylation to yield the corresponding alpha, beta- unsaturated carbonyl compounds and upon sensitized irradiation they underwent dimersation arising through a 2+2 cycloaddition reaction. Our studies on 3(2H)-furanones revealed that these compounds are thermally stable, while they undergo extensive decomposition to intractable mixtures under the influence of light. Similarly, the novel dibenzoylalkenes- type systems containing hetroatomatic rings synthesized by us also underwent extensive decomposition under the influence of heat. Some of the 3(2H)-furanones synthesized by us exhibit remarkable anti-proliferative activity.
Jean John, Vadakkan; Dr.Prathapan, S(Cochin University of Science & Technology, September , 2002)
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Abstract:
In this thesis, we report our endeavours in the synthesis of a few polycyclic compounds. We were interested in the synthesis of a few bicyclic compounds designed to undergo interesting photochemical transformations including tripletmediated di-π-methane rearrangement and/or competing singlet-mediated electrocyclic reactions. Our target molecules have "inbuilt" structural features which will potentially alter the photochemistry of the substrate under consideration.The present investigation was undertaken to test our hypothesis on selective intramolecular quenching of singlet or triplet excited states of molecules.We adopted Dies-Alder reaction for the synthesis of several of the bicyclic compounds we were interested in. Some of the precursor dienes synthesised by us are capable of undergoing intramolecular cycloaddition reactions as well. So, it was important to delineate the conditions and structural features that will enable a particular molecule to undergo intermolecular and intramolecular Dies-Alder reaction when treated with a suitable dienophile.Though, the main focus of this thesis is on the synthesis of bicyclic and tricyclic systems capable of undergoing di-π-methane rearrangement, in the last chapter of this thesis, we describe our findings on the synthesis of a few dispirocompounds. These systems were encountered as unexpected products in the attempted synthesis of novel dibenzoylalkene-type systems. Consequently, a brief survey on the synthesis and transformations of dibenzoylalkenes is also included as an integral part of this thesis.
Description:
Department of Applied Chemistry, Cochin University of Science and Technology