Rajesh,G; Muraleedharan Nair,K R(Cochin University of Science and Technology, February , 2001)
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Abstract:
The present study on the characterization of probability distributions using the residual entropy function. The concept of entropy is extensively used in literature as a quantitative measure of uncertainty associated with a random phenomenon. The commonly used life time models in reliability Theory are exponential distribution, Pareto distribution, Beta distribution, Weibull distribution and gamma distribution. Several characterization theorems are obtained for the above models using reliability concepts such as failure rate, mean residual life function, vitality function, variance residual life function etc. Most of the works on characterization of distributions in the reliability context centers around the failure rate or the residual life function. The important aspect of interest in the study of entropy is that of locating distributions for which the shannon’s entropy is maximum subject to certain restrictions on the underlying random variable. The geometric vitality function and examine its properties. It is established that the geometric vitality function determines the distribution uniquely. The problem of averaging the residual entropy function is examined, and also the truncated form version of entropies of higher order are defined. In this study it is established that the residual entropy function determines the distribution uniquely and that the constancy of the same is characteristics to the geometric distribution
Neema, Ani Mangalam; Dr.Prathapachandra Kurup,M R(Cochin University of Science & Technology, December , 2010)
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Abstract:
The current work deals with the synthesis and characterization of metal
complexes derived from some substituted acylhydrazones. The hydrazones under
investigation were characterized by IR, UV, NMR spectral studies and the
molecular structure of one of the hydrazones was solved by single crystal XRD
studies. In the present work dioxovanadium(V), manganese(II), cobalt(II/III),
nickel(II), copper(II), zinc(II) and cadmium(II) complexes were synthesized and
characterized by various spectroscopic techniques, molar conductance
measurements, magnetic susceptibility measurements and cyclic voltammetry.
Single crystals of some of the complexes were isolated and characterized by
single crystal X-ray diffraction.The thesis is divided into eight chapters. Chapter 1 gives an introduction
on hydrazones, diversity in their chelating behavior and their application in
various fields. This chapter also describes different analytical techniques
employed for the characterization of hydrazones and their metal complexes.
Chapter 2 includes the synthesis and characterization of two substituted
acylhydrazones. This chapter also discusses how the coordination behavior of
hydrazones under investigation is interesting. Chapters 3-8 discuss the synthesis
and characterization of some transition metal complexes derived from the
acylhydrazones under study.The hydrazones synthesized were found to exist in the amido form.
Various characterization techniques were carried out to explore the structure of
the synthesized complexes. The results indicate that both the hydrazones
coordinate through the pyridyl and azomethine nitrogens and amide oxygen either
in enolate or neutral form. Out of synthesized complexes V(V), Zn/Cd(II) and
one of the cobalt complex was found to diamagnetic. We could isolate single
crystals of some of the complexes and most of the complexes crystallized were
found to have a distorted octahedral geometry. Thus X-ray crystallographic study
which was used as major tool in the structure determination revealed that the
hydrazones undergo a rotation about the azomethine bond on complexation. We
hope the work presented in the thesis would be helpful for those who are working
in the field of metal complexes and can further they can be utilized for various
applications.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology
Suja, K P; Dr.Arumughan, C; Dr. Jayalekshmy, A(RRL,CSIR, January , 2003)
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Abstract:
In the present study on natural antioxidants, the focus has been kept
mainly on oil seeds, especially sesame and its by-products. Sesame, which has been
under cultivation in India for centuries is called the 'Queen of oil seed crops' because of
the high yield of oil obtained and the nutritional qualities of the seed, oil, and meal.
Though India is the largest producer of sesame in the world, research on the various
health benefits of sesame has been carried out by Japanese Sesame has an important place
in the foods and tradit..ional medicine of India from time immemorial. Foreseeing the
potential of sesame and its byproducts as an important antioxidant source and its
availability in bulk, the present study was focussed on Sesamum species. There are not
many reports on the wild species of Sesamum in India, especially of the Kerala region.
Hence, in the present study we also included antioxidants of Sesamurnrnalabaricumdistributed
throughout the coastal region.The important characteristics of sesame are attributed to the presence of
the umquc compounds lignans. Lignans arc a group of natural products of phenyl propanoid ongm, whieh are widely distributed in nature. They display important
physiological functions in plants, in human nutrition and medicine, given their extensive
health promotive and curative properties. Much interest has been focussed on their
effectiveness as antineoplastic agents and research in this area has revealed several modes
of action by which they can regulate the growth of mammalian cells. Sesame is an
important source of furofuran lignans, of which sesamin and the rare oxygenated
derivative sesamoIin are the most abundant. Others include sesamol and glucosides of
lignans. Sesarnin and episesamin are reported to have hypocholesterolemic effect,
suppressive effect on chemically induced cancer, alleviation of allergy symptoms etc.
Sesamol, sesamolin and the lignan glycosides are reported to inhibit lipid peroxidation.
Present investigation on sesame and its byproducts have been carried out to explore the
possibility of developing a natural antioxidant extract from available resources to be used
as a substitute to synthetic ones in vegetable oils and foods. Preliminary analysis showed
that sesame cake, a byproduct could still be utilized as a major source of lignans. Sesame
cake, which is now used only as a cattlefeed, can be better utilized in the form of a
valuable antioxidant source. The present study explains the development of a feasible
process for the extraction of antioxidant compounds from sesame cake. The antioxidant
extract so prepared from sesame cake has been tested for vegetable oil protection and is
found to be effective at low concentration. In addition, studies also include the
antioxidant, radical scavenging, anticancer, mosquitocidal and pesticidal activities of
extract and individual compounds.
Leena, R; Dr.Girish Kumar, K(Cochin University Of Science And Technology, October 31, 2012)
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Abstract:
Voltammetric methods are applicable for the determination of a wide
variety of both organic and inorganic species. Its features are compact
equipment, simple sample preparation, short analysis time, high accuracy and
sensitivity. Voltammetry is especially suitable for laboratories in which only a
few parameters have to be monitored with a moderate sample throughput. Of
various electrode materials, glassy carbon electrode is particularly useful
because of its high electrical conductivity, impermeability to gases, high
chemical resistance, reasonable mechanical and dimensional stability and
widest potential range of all carbonaceous electrodes. Electrode modification
is a vigorous research area by which the electrochemical determination of
various analyte species is facilitated. The scope of pharmaceutical analysis
includes the analytical investigation of pure drug, drug formulations,
impurities and degradation products of drugs, biological samples containing
the drugs and their metabolites with the aim of obtaining data that can
contribute to the maximal efficacy and maximal safety of drug therapy.
This thesis presents the modification of glassy carbon electrode using
metalloporphyrin and dyes and subsequently using these modified electrodes
for the determination of various pharmaceuticals. The thesis consists of 9
chapters.
Description:
Department of Applied Chemistry
Cochin University of Science and Technology
Suresh, P V; Dr.Chandrasekaran,M(Cochin University of Science and Technology, October 10, 1996)
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Abstract:
In this thesis an attempt is made to explore the potential of marine fungi for the production of chitinolytic enzymes and to recognize the ability to hydrolyse native chitin through submerged as well as solid substrate fermentation culture conditions, using wheat bran and shellfish processing waste such as ‘prawn waste’ as solid substrates. Attempt was made to isolate a potential chitinase producing fungus from marine environment and to develop an ideal bioprocess for the
production ofchitolytic enzymes.Present study indicate scope for utilization of B. bassiana
for industrial production of chitinase using prawn waste as solid substrate employing solid substrate fermentation.
Description:
Department of Biotechnology. Cochin University of Science and Technology
Chinthu, Romeo; Dr. Paulose, C S(Cochin University of Science and Technology, August 17, 2012)
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Abstract:
The present study deals with the Cholinergic Receptor subtypes functional regulation in spinal cord injured monoplegic rats: Effect of 5-HT GABA and bone marrow cells.Spinal cord injury causes permanent and irrevocable motor deficits and neurodegeneration. Disruption of the spinal cord leads to diminished transmission of descending control from the brain to motor neurons and ascending sensory information. Behavioural studies showed deficits in motor control and coordination in SCI rats. Cholinergic system plays an important role in SCI, the evaluation of which provides valuable insight on the underlying mechanisms of motor deficit that occur during SCI. The cholinergic transmission was studied by assessing the muscarinic and nicotinic receptors; cholinergic enzymes- ChAT and AChE; second messenger enzyme PLC; transcription factor CREB and second messengers - IP3, cAMP and cGMP. We observed a decrease in the cholinergic transmission in the brain and spinal cord of SCI rats. The disrupted cholinergic system is the indicative of motor deficit and neuronal degeneration in the spinal cord and brain regions. SCI mediated oxidative stress and apoptosis leads to neuronal degeneration in SCI rats. The decreased expression of anti oxidant enzymes – SOD, GPx and neuronal cell survival factors - BDNF, GDNF, IGF-1, Akt and cyclin D2 along with increased expression of apoptotic factors – Bax, caspase-8, TNFa and NF-kB augmented the neuronal degeneration in SCI condition. BMC administration in combination with 5-HT and GABA in SCI rats showed a reversal in the impaired cholinergic neurotransmission and reduced the oxidative stress and apoptosis. It also enhanced the expression of cell survival factors in the spinal cord region. In SCI rats treated with 5-HT and GABA, the transplanted BMC expressed NeuN confirming that 5-HT and GABA induced the
differentiation and proliferation of BMC to neurons in the spinal cord. Neurotrophic factors and anti-apoptotic elements in SCI rats treated with 5-HT and GABA along with BMC rendered neuroprotective effects accompanied by improvement in behavioural deficits. This resulted in a significant reversal of altered cholinergic neurotransmission in SCI. The restorative and neuro protective effects of BMC in combination with 5-HT and GABA are of immense therapeutic
significance in the clinical management of SCI.
Description:
Department of Biotechnology, Cochin University of Science and Technology
Bindhu, Jacob; Dr.Sugunan, S(Cochin University of Science & Technology, February , 1998)
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Abstract:
In this thesis an attempt has been made to compare the catalytic activity of
some medium and large pore zeolites in a few alkylation and acylation reactions. The
work reported in the present study is basically centered around the following zeolites
namely, ZSM-5, mordenite, zeolite Y and beta. The major reactions carried out were
benzoylation of o-xylene, propionylation of toluene and anisole and benzylation of 0xylene.The programme involves the synthesis, modifications and characterization of
the zeolite catalysts by various methods. The influence of various parameters such as
non-framework cations, Si/AI ratio of zeolites, temperature of the reaction, catalyst
concentration, molar ratio of the reactants and recycling of the catalysts were also
examined upon the conversion of reactants and the formation of the desired products
in the alkylation / acylation reactions.The general conclusions drawn by us from the results obtained are summarized
in the last chapter of the thesis. Zeolite beta offers interesting opportunities as a
potential catalyst in alkylation reactions and the area of catalysis by medium and large
pore zeolites is very fascinating and there is plenty of scope for further research in this
field. Moreover, zeolite based catalysts are effective in meeting current industrial
processing and more stringent environment pollution limits.
Description:
Department of Applied Chemistry, Cochin
University of Science and Technology
Bindhu, Jacob; Dr.Sugunan, S(Cochin University Of Science And Technology, February 13, 1998)
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Abstract:
Zeolites have established themselves as industrial catalysts for over two
decades for a variety of hydrocarbon processing reactions where acidity and shape
selectivity are important factors. As solid catalysts, zeolites may be advantageous and
superior compared to their homogenous counterparts due to their characteristic
properties. It is only in recent years that the utility of zeolites for organic synthesis is
recognized for producing specific organic intermediates and fine chemicals in high
selectivity.
In this thesis an attempt has been made to compare the catalytic activity of
some medium and large pore zeolites in a few alkylation and acylation reactions. The
work reported in the present study is basically centered around the following zeolites
namely, ZSM-5, mordenite, zeolite Y and beta. The major reactions carried out were
benzoylation of o-xylene, propionylation of toluene and anisole and benzylation of oxylene.
.
The programme involves the synthesis, modifications and characterization of
the zeolite catalysts by various methods. The influence of various parameters such as
non-framework cations, Si/Al ratio of zeolites, temperature of the reaction, catalyst
concentration, molar ratio of the reactants and recycling of the catalysts were also
examined upon the conversion of reactants and the formation of the desired products
in the alkylation/ acylation reactions.
The general conclusions drawn by us from the results obtained are summarized
in the last chapter of the thesis. Zeolite beta ofi'ers interesting opportunities as a
potential catalyst in alkylation reactions and the area of catalysis by medium and large
pore zeolites is very fascinating and there is plenty of scope for further research in this
field. Moreover, zeolite based catalysts are effective in meeting current industrial
processing and more stringent environment pollution limits.
Description:
Department of Applied Chemistry, Cochin
University of Science and Technology
Johny,Scaria; Unnikrishnan Nair, N(Department of Statistics,Faculty of Science, 2003)
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Abstract:
The study deals with the distribution theory and applications of concomitants from the Morgenstern family of bivariate distributions.The Morgenstern system of distributions include all cumulative distributions of the form FX,Y(X,Y)=FX(X) FY(Y)[1+α(1-FX(X))(1-FY(Y))], -1≤α≤1.The system provides a very general expression of a bivariate distributions from which members can be derived by substituting expressions of any desired set of marginal distributions.It is a brief description of the basic distribution theory and a quick review of the existing literature.The Morgenstern family considered in the present study provides a very general expression of a bivariate distribution from which several members can be derived by substituting expressions of any desired set of marginal distributions.Order statistics play a very important role in statistical theory and practice and accordingly a remarkably large body of literature has been devoted to its study.It helps to develop special methods of statistical inference,which are valid with respect to a broad class of distributions.The present study deals with the general distribution theory of Mk, [r: m] and Mk, [r: m] from the Morgenstern family of distributions and discuss some applications in inference, estimation of the parameter of the marginal variable Y in the Morgestern type uniform distributions.