Suni, V; Dr.Prathapachandra Kurup,M R(Cochin University of Science and Technology, August 29, 2005)
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Abstract:
The present work deals with the investigations on sthe structural spectral and magnetic interactions of transition metal complexes of multidentate ligands from D1-2-pyridyl ketone and N(4)-Substituted thiosemicarbazides.Thiosemicarbazones are thiourea derivatives with the general formula R2N—
C(S)—NH—N=CR2. In the solution state, the thiosemicarbazones exhibit the thionethiol tautomerism similar to the keto-enol tautomerism, and in solution state the thiol form predominates and a deprotonation at the thiolate group in alcoholic medium enhances the coordination abilities ofthe thiosemicarbazones.The magnetochemistry of metal complexes of di-2-pyridyl ketone is a current
hot subject of research, which mainly owes to the excellent structural diversity of the complexes ranging from cubanes to clusters, with promising ferromagnetic outputs.Only few efforts were aimed at
the magnetochemistry of metal complexes of thiosemicarbazones, and that too were concerned with the complexes of bisttltioscinicarbazones). However, as far as the monothiosemicarbazones are concerned, the magnetochemistry of transition metal complexes of di-2-pyridyl ketone thiosemicarbazones turned up quite unexplored. Consequently, an investigation into it appeared novel and promising to us and that prompted this study, which can be regarded as the initial step towards exploring the magnetochemistry of thiosemicarbazone complexes, especially of di-2-pyridyl ketone derivatives.We could successfully isolate single crystals suitable for X-ray diffraction for the first three ligands.
To conclude, we have synthesized some new thiosemicarbazones and their transition metal complexes and studied their structural, spectral and magnetic attributes. Some ofthe complexes revealed interesting stereochemistries and possible bridging characteristics with spectroscopic evidences. Unfortunately, single crystal Xray diffraction studies could not be carried out for many of these interesting compounds due to the lack of availability of suitable quality single crystals. However,
the magnetic studies provided support for the proposed stereochemistry giving evidences for their magnetically concentrated nature. The magnetic susceptibilities measured at six different temperatures in the 80-298 K range are fitted into different magnetic equations, which provided an idea about the magnetic behavior of the compounds under study. Some of the copper, oxovanadium, nickel and cobalt
complexes are found to possess anomalous magnetic moments, i.e., they revealed no regular gradation with temperature. However, some other copper complexes are observed to be antiferromagnetic, due to super-exchange pathways. The manganese complexes and one of the cobalt complexes are also observed to be antiferromagnetic in nature. However, some nickel complexes have turned up to be ferromagnetic. Accordingly, the versatile stereoehemistry and magnetic behavior of the complexes
studied, prompt us to conclude that the transition metal complexes of di-2-pyridyl ketone thiosemicarbazones are promising systems for potential magnetic applications.
Description:
Department of Applied Chemistry,Cochin University of Science and Technology
Divya, S; Dr. A. Mujeeb(Cochin University of Science and Technology, May 20, 2015)
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Abstract:
This Study overviews the basics of TiO2with respect to its structure, properties and applications. A brief account of its structural, electronic and optical properties is provided. Various emerging technological applications utilising TiO2 is also discussed.Till now, exceptionally large number of fundamental studies and application-oriented research and developments has been carried out by many researchers worldwide in TiO2 with its low-dimensional nanomaterial form due to its various novel properties. These nanostructured materials have shown many favourable properties for potential applications, including pollutant photocatalytic decomposition, photovoltaic cells, sensors and so on. This thesis aims to make an in-depth investigation on different linear and nonlinear optical and structural characteristics of different phases of TiO2. Correspondingly, extensive challenges to synthesise different high quality TiO2 nanostructure derivatives such as nanotubes, nanospheres, nanoflowers etc. are continuing. Here, different nanostructures of anatase TiO2 were synthesised and analysed. Morphologically different nanostructures were found to have different impact on their physical and electronic properties such as varied surface area, dissimilar quantum confinement and hence diverged suitability for different applications. In view of the advantages of TiO2, it can act as an excellent matrix for nanoparticle composite films. These composite films may lead to several advantageous functional optical characteristics. Detailed investigations of these kinds of nanocomposites were also performed, only to find that these nanocomposites showed higher adeptness than their parent material. Fine tuning of these parameters helps researchers to achieve high proficiency in their respective applications. These innumerable opportunities aims to encompass the new progress in studies related to TiO2 for an efficient utilization in photo-catalytic or photo-voltaic applications under visible light, accentuate the future trends of TiO2-research in the environment as well as energy related fields serving promising applications benefitting the mankind. The last section of the thesis discusses the applicability of analysed nanomaterials for dye sensitised solar cells followed by future suggestions.
Sumangala,R; Saseendran Pillai, P R(Cochin University OF Science and Technology, December , 1996)
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Abstract:
The main objective of carrying out this investigation is to develop suitable transducer array systems so that underwater pipeline inspection could be carried out in a much better way, a focused beam and electronic steering can reduce inspection time as well. Better results are obtained by optimizing the array parameters. The spacing between the elements is assumed to be half the wavelength so that the interelement interaction is minimum. For NDT applications these arrays are operated at MHz range. The wavelengths become very small in these frequency ranges. Then the size of the array elements becomes very small, requiring hybrid construction techniques for their fabrication. Transducer elements have been fabricated using PVDF as the active, mild steel as the backing and conducting silver preparation as the bonding materials. The transducer is operated in the (3,3) mode. The construction of a high frequency array is comparatively complicated. The interelement spacing between the transducer elements becomes considerably small when high frequencies are considered. It becomes very difficult to construct the transducer manually. The electrode connections to the elements can produce significant loading effect. The array has to be fabricated using hybrid construction techniques. The active materials has to be deposited on a proper substrate and etching techniques are required to fabricate the array. The annular ring, annular cylindrical or other similar structural forms of arrays may also find applications in the near future in treatments were curved contours of the human body are affected.
Vijayan, K K; Dr.Abdul Rasheed, T M(Cochin University Of Science And Technology, October 8, 2003)
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Abstract:
The central theme of this research concerns the study of vibrationally excited
molecules. We have used the local mode description of such vibrational states, and this
-model has now gained general acceptance. A central feature of the model is the
Wloealizafion of vibrational energy. A study of these high—energy localized states provides
example, becauseof this localization, overtone spectra, which measure the absorption of
T vibrational energy, are extremely sensitive to the properties of X-H bonds. We also use
-overtone spectra to study the conformation of molecules, i.e., the relative internal
orientation of their bonds. The thesis comprises six chapters
Description:
Department of Physics Cochin
University of Science and Technology
Lakshmanan, P T; Dr.Krishnan Nambisan, P N(Cochin University Of Science And Technology, January , 1982)
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Abstract:
The subsequent chapters of the Thesis deal with the toxic
effects of mercury, copper, zinc und~1ead on these bivalve
molluecs, their accumulation and distribution among various
organs of the animals and also the motel retention winstica
by the three species. Static biousauy tests have been conducted
in these studies. It was found that the concentrations of
the various metals studied in these organism are well below
the permitted level given far ease ahellfienes (crab and ehrimgi
and that these maliuscs are very good integrators ef trace
metals from their environment and may be used as an indicator
organism sf metal pallutaute.
The present investigutionsemphaeie the need for a clean
coastal water and gives a serious warning regarding the possiblc
route of heavy metals in ta human body thraugh marine food
chain.
Description:
School Of Marine Sciences
Cochin University Of Science And Technology
Namboothiripad,P V S; Dr.Parameswaran, Nair N(Cochin University of Science and Technology, November 1, 1979)
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Abstract:
The present study is intended to provide a new scientific approach to the solution of the worlds cost engineering problems encountered in the chemical industries in our nation. The problem is that of cost estimation of equipments especially of pressure vessels when setting up chemical industries .The present study attempts to develop a model for such cost estimation. This in turn is hoped would go a long way to solve this and related problems in forecasting the cost of setting up chemical plants.
Zeena, Hamza P; Dr.Thomas, Kurian(Cochin University of Science And Technology, October , 2012)
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Abstract:
Biodegradation is the chemical degradation of materials brought
about by the action of naturally occurring microorganisms. Biodegradation
is a relatively rapid process under suitable conditions of moisture, temperature
and oxygen availability. The logic behind blending biopolymers such as starch
with inert polymers like polyethylene is that if the biopolymer component is
present in sufficient amount, and if it is removed by microorganisms in the
waste disposal environment, then the base inert plastic should slowly
degrade and disappear.
The present work focuses on the preparation of biodegradable and
photodegradable blends based on low density polyethylene incorporating small
quantities of ionomers as compatibilizers.
The thesis consists of eight chapters. The first chapter presents an
introduction to the present research work and literature survey. The details of
the materials used and the experimental procedures undertaken for the study
are described in the second chapter. Preparation and characterization of low
density polyethylene (LDPE)-biopolymer (starch/dextrin) blends are
described in the third chapter. The result of investigations on the effect of
polyethylene-co-methacrylic acid ionomers on the compatibility of LDPE
and starch are reported in chapter 4. Chapter 5 has been divided into two
parts. The first part deals with the effect of metal oxides on the
photodegradation of LDPE. The second part describes the function of
metal stearates on the photodegradation of LDPE. The results of the
investigations on the role of various metal oxides as pro-oxidants on the
degradation of ionomer compatibilized LDPE-starch blends are reported in
chapter 6. Chapter 7 deals with the results of investigations on the role of
various metal stearates as pro-oxidants on the degradation of ionomer
compatibilized LDPE-starch blends. The conclusion of the investigations is
presented in the last chapter of the thesis.
Description:
Department of Polymer Science and Rubber Technology,
Cochin University of Science and Technology
The present study is an attempt to find out the ralation between RNA/DNA ratio, protein,percentage growth rate and specific growth rate of prawn,Penaeus indicus with respect to Nervous system, Eyestalk and Muscle tissues during ontogenesis. We have isolated and purified a natural agglutinin in the hemolymph of P.indicus with antigenecity, agglutinating, hemolytic and antibacterial properties. The influence of growth and environmental parameters on the level of agglutinin in the hemolymph was studied. Agglutinin concentration during normal growth process was compared. The agglutinin concentration in the hemolymph was quantified through developing ELISA, which is useful in health monitoring studies of individual species. Complete amino acid composition of both the subunits of P.indicus agglutinin were analysed. P.indicus agglutinin showed similarity to those proteins having antigenecity,hemolytic and agglutinating properties.Hence, agglutinin was considered as a natural defence protein in the hemolymph of P.indicus responsible for immune surveillance. The humoral defence mechanism of agglutinin was a co-operative effort with hemocytes and complement system. The composition of isolated agglutinin of P.indicus amino acids will be helpful in the synthesis of new antibacterial analogues which can be used against disease causing organisms.
Description:
Dept. of Biotechnology, Cochin University of Science and Technology
Manjusha,K P; Dr.Saleena, Mathew(Cochin University of Science and Technology, April , 2011)
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Abstract:
The present study is aimed at the isolation and characterization of glycosaminoglycans from selected tissues of two commercially important species of cephalopods;squid,Loligo duvauceli and cuttlefish,Sepia pharaonis,keeping in view of the aforementioned benefits on the utilization of waste generated during processing.The cephalopod GAGs may also be expected to have an effect on various physiological functions based on the results obtained from GAGs from other sources.In addition,knowledge of the chemical structure of macromolecules that constitute major components of extracellular matrix(ECM) will be helpful in understanding their interactions with other matrix components.
Description:
School of Industrial Fisheries,
Cochin University of Science and Technology
Bijina, B; Dr.Chandrasekaran,M(Cochin University of Science & Technology, May , 2006)
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Abstract:
Protease inhibitors are one of the most important tools of nature for
regulating the proteolytic activity of their target proteases. They are
synthesized in biological systems and they play a critical role in controlling
a number of diverse physiological functions. The current investigation
focused on the isolation, purification and characterization of a novel
protease inhibitor from Moringa oleifera. The results obtained during the
course of study opens new perspectives for the utilization of protease
inhibitor from Moringa oleifera for various pharmaceutical, agricultural and
food industries. The biological and physicochemical properties exhibited by
the novel protease inhibitor from Moringa oleifera clearly testify its
suitability for the development as a drug for application in pharmaceutical
industries such as anticoagulant agent or biocontrol agent in agriculture and
even as a food preservant. There is a scope for further research on the
structure elucidation and protein engineering towards a wide range of
further applications. Detailed structure/function analysis of these proteins is
important to facilitate their use in genetic engineering for various
applications.
Description:
Department of Biotechnology,
Cocbin University of Science and Technology
Sapna, K; Dr.Elyas, K K(Cochin University of Science And Technology, March , 2013)
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Abstract:
The microorganisms are recognized as important sources of protease
inhibitors which are valuable in the fields of medicine, agriculture and
biotechnology. The protease inhibitors of microbial origin are found to be versatile
in their structure and mode of inhibition that vary from those of other sources.
Although surplus of low molecular weight non-protein protease inhibitors from
microorganisms have been reported, there is a dearth of reports on proteinaceous
protease inhibitors. The search for new metabolites from marine organisms has
resulted in the isolation of more or less 10,000 metabolites (Fuesetani and
Fuesetani, 2000) many of which are gifted with pharmacodynamic properties. The
existence of marine microorganisms was reported earlier, and they were found to
be metabolically and physiologically dissimilar from terrestrial microorganisms.
Marine microorganisms have potential as important new sources of enzyme
inhibitors and consequently a detailed study of new marine microbial inhibitors
will provide the basis for future research (Imada, 2004).
Description:
Department of Biotechnology, Cochin University of Science and Technology
Joshy, M K; Dr.Rani,Joseph(Cochin University of Science and Technology, October , 2007)
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Abstract:
The aim of this
investigation is to study the effectiveness of isora fibre as reinforcement material
in short and long forms, for unsaturated polyester and epoxy resins.Studies on the optimization of fibre length and fibre loading of
randomly oriented isora-polyester composite are described.The
salient features of the alkali treatment of short isora fibre on the properties of
randomly oriented isora-polyester composite are outlined in this thesis.The
effect of surface modification of the hydrophilic isora fibre by different chemical
treatments on the properties of randomly oriented isora-polyester composite is
outlined.The properties of oriented and
randomly oriented isora fibre reinforced epoxy composites with special reference
to the effect of fibre loading are reported and also the dynamic mechanical
properties ofthe oriented and randomly oriented isora-polyester and isora-epoxy
composites are presented and the water absorption kinetics
of oriented and randomly oriented isora-polyester composites and oriented isoraepoxy
composites are given. The effect of hot air oven aging on the tensile and
flexural properties of oriented isora-polyester and isora-epoxy composites are
also reported in this thesis.
Description:
Department of Polymer Science and Rubber Technology,Cochin University of
Science and Technology