Sasidharan, Nair S; Dr.Babu, Joseph K(Cochin University of Science and Technology, 1977)
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Abstract:
The present thesis deals with some studies in molecular dynamics using spectroscopic data. Two new approximation procedures the variable method and the average bonding energy criterion have been developed for a reliable calculation of molecular force fields and applied to several molecular species belonging to the xy2 type.
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Department of Physics, Cochin University of Science & Technology
Santhakumari, B; Dr.Krishna Pillai, M G(Cochin University of Science And Technology, 1976)
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Abstract:
This thesis deals with some studies in molecular mechanic using spectroscopic data. It includes an improvement in the parameter technique for the evaluation of exact force fields, the introduction of a new and simple algebraic method for the force field calculation and a study of asymmetric variation of bonding forces along a bond.
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Department of physics, Cochin University of Science And Technology
Annie,Joseph Vallamattom; Dr.Krishna Pillai, M G(Cochin University of Science And Technology, November , 1978)
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Abstract:
This thesis is divided into two parts. The first part deals with some studies in molecular mechanics Using spectroscopic data and has four chapters in it. Certain approximation methods for the evaluation of molecular force fields are herein developed The second part, which consists of the last two chaptcrs, deals with infrared spectral studies of ternary liquid systems and a polymer film prepared by glow discharge method.
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Department of physics, Cochin University of Science And Technology
Kuriakose, V C; Dr.Babu, Joseph K(Cochin University of Science And Technology, September , 1982)
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Abstract:
The thesis deals with certain quantum field systems exhibiting spontaneous symmetry breaking and their response to temperature. These models find application in diverse branches such as particle physics, solid state physics and non~linear optics. The nature of phase transition that these systems may undergo is also investigated. The thesis contains seven chapters. The first
chapter is introductory and gives a brief account of the various phenomena associated with spontaneous symmetry breaking. The chapter closes with anote on the effect of temperature on quantum field systems. In chapter 2, the spontaneous symmetry breaking phenomena are reviewed in more detail. Chapter 3, deals with the formulation of ordinary and generalised sine-Gordon field theories on a lattice and the study of the nature of phase transition occurring in these systems. In chapter 4, the effect of temperature on these models is studied, using the effective potential method. Chapter 5 is a continuation of this study for another model, viz, the
m6 model. The nature of phase transition is also studied. Chapters 5 and 6 constitute a report of the investigations on the behaviour of coupling constants under thermal excitation D1 $4 theory, scalar electrodynamics, abelian and non-abelian gauge theories
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Department of physics, Cochin University of Science And Technology
Vijayakumar,A; Dr.Thrivikraman, T(Cochin University of Science and Technology, July , 1985)
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Abstract:
This thesis is an attempt to initiate the development of a discrete geometry of the discrete
plane H = {(qmxo,qnyo); m,n e Z - the set of integers}, where q s (0,1) is fixed and (xO,yO) is a fixed point in the first quadrant of the complex plane, xo,y0 ¢ 0. The discrete plane was first considered by Harman in 1972, to evolve a discrete analytic function theory for geometric difference functions. We shall mention briefly, through various sections, the principle
of discretization, an outline of discrete a alytic function theory, the concept of geometry of space and also summary of work done in this thesis
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Department
of Mathematics and Statistics,Cochin University of Science & Technology
Ramachandra, Sharma N; Dr.Madhavan Pillai, P(Cochin University of Science And Technology, March , 1988)
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Abstract:
Strychnine is the major alkaloid present in the seeds of _Strychnos, nuxvomica tree which grow naturally in this area. Strychnine has a very complex chemical structure and is known to stimulate all portions of the central nervous system with preference to the spinal cord. However, it is a powerful convulsant and death results from asphyxia. Consequently strychnine has no therapeutic application in the western system of medicine at present. The objective of this work, therefore, was to convert strychnine by microbial transformation into a product having more desirable pharmacological properties so that this locally available natural product may find some use in the preparation of a therapeutic agent.
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Department of applied chemistry, Cochin University of Science And Technology
Geetha, S; Dr.Jathavedan, M(Cochin University of Science and Technology, July , 1994)
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Abstract:
The study of stability problems is relevant to the study of structure of a physical system. It 1S particularly important when it is not possible to probe into its interior and obtain information on its structure by a direct method. The thesis states about stability theory that has become of dominant importance in the study of dynamical systems. and has many applications in
basic fields like meteorology, oceanography, astrophysics and geophysics- to mention few of them. The definition of stability was found useful 1n many situations, but inadequate in many others so that a host of other important concepts have been introduced in past many years which
are more or less related to the first definition and to the common sense meaning of stability.
In recent years the theoretical developments in the studies of instabilities and turbulence have been as profound as the developments in experimental methods. The study here
Points to a new direction for stability studies based on Lagrangian formulation instead
of the Hamiltonian formulation used by other authors.
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Division of Mathematics,
School of Mathematical Sciences, Cochin University of Science and
Technology
Sreedharan Nair, M N; Dr.Babu, Joseph K(Cochin University of Science and Technology, November 2, 1981)
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Abstract:
This thesis is devoted to theoretical studies on the properties of hadrons on the basis of bag models. It contains some applications of the traditional.HIT bag model to the spectroscopy and decay of hadrons. The inadequacies of the model are brought out and a new version of the model, called the variable pressure bag model, is developed. Some of the Phenomenological applications of this model are discussed and the predictions are compared with experiment.
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Department of Physics, Cochin University of Science & Technology
Dhanya, T P; Dr.Sugunan, S(Cochin University Of Science And Technology, November 7, 2012)
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Abstract:
Semiconductor photocatalysis has received much attention during last
three decades as a promising solution for both energy generation and
environmental problems. Heterogeneous photocatalytic oxidation allows the
degradation of organic compounds into carbon dioxide and water in the
presence of a semiconductor catalyst and UV light source. The •OH radicals
formed during the photocatalytic processes are powerful oxidizing agents and
can mineralise a number of organic contaminants. Titanium dioxide (TiO2),
due to its chemical stability, non-toxicity and low cost represents one of the
most efficient photocatalyst. However, only the ultraviolet fraction of the solar
radiation is active in the photoexcitation processes using pure TiO2 and
although, TiO2 can treat a wide range of organic pollutants the effectiveness of
the process for pollution abatement is still low.
A more effective and efficient catalyst therefore must be formulated.
Doping of TiO2 was considered with the aim of improving photocatalytic
properties.
In this study TiO2 catalyst was prepared using the sol-gel method. Metal
and nonmetal doped TiO2 catalysts were prepared. The photoactivity of the
catalyst was evaluated by the photodegradation of different dyes and pesticides
in aqueous solution.
High photocatalytic degradation of all the pollutants was observed with
doped TiO2. Structural and optical properties of the catalysts were characterized
using XRD, BET surface area, UV-Vis. DRS, CHNS analysis, SEM, EDX, TEM,
XPS, FTIR and TG. All the catalysts showed the anatase phase. The presence of
dopants shifts the absorption of TiO2 into the visible region indicating the
possibility of using visible light for photocatalytic processes.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology
Ambili, V K; Dr.Sugunan, S(Cochin University of Science and Technology, April , 2011)
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Abstract:
To meet the challenges related to the chemical industry,development of efficient catalysts is necessary.The mesoporous materials like SBA-15 are considered as good catalyst candidates of 21st century.SBA-15 mesoporous materials are catalytically inactive,but allow the dispersion of catalytically active phases into the framework.So these materials can be considered as an interesting alternative for preparing catalytically active metal nanoparticles in-situ into it.In the present work various transition metals are incorporated to improve the catalytic activity of SBA-15 material.The fundamental aspects of the preparation,characterization and the activity studies are briefly viewed in this thesis. Systematic investigation of the physico-chemical properties and catalytic activity studies of the prepared materials were carried out and presented in this Study.
Description:
Department of Applied Chemistry,Cochin University of Science and Technology
Joyes, Jacob; Dr.Sugunan, S(Cochin University of Science and Technology, December 14, 2009)
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Abstract:
Scientists throughout the world are in search of a better methodology to reduce the use of environmentally hazardous chemicals common in industries .A significant contribution in this field is given by different redox catalysts in oxidation reactions. The oxidation of organic substrates represents one of the most important industrial chemical reactions, explaining the significant efforts invested in the research and development of new heterogeneous catalysts with increased activities and selectivities in these type reactions[l-4|. Hence liquid phase reactions like epoxidation of cylcohexene and hydroxylation of phenol were carried out with a new outlook in the challenge using CeO2/TiO;; and CuO/TiO2 catalysts denoted as TiO2-Ce as TiO2-Cu respectively in this work. Also different wt% of metals incorporated titania catalysts like 3, 6, 9 wt% CeO2/TiO; and CuO/TiO;were subjected to the present study .The interaction between metal oxides and the oxide supports have attracted much attention because of the wide applications of supported metal oxide systems[7,8]. It is well known that supported oxides of transition metals are widely used as catalysts for various reactions. Titania as well its metal modified catalysts systems afford high activity and selectivity in the liquid phase epoxidation of cyclohexene[9]. Cyclohexene epoxide is obtained as the major product during the reaction with small amounts of allylic substitution products.This chapter gives an idea about the liquid phase oxidation reactions like epoxidation of cylcohexene and hydroxylation of phenol in which many industrially important products are formed. Here discusses about the redox properties of the ceria and copper incorporated titania catalysts.The epoxidation of cyclohcxene is carried out efficiently over the prepared systems with the selective formation of cyclohexane epoxide. This reaction hints that it might be possible to create cleaner nylon chemistry. The total acidity of the prepared systems plays an important role in determining the catalytic activity in the dehydrogenation of cyclohexane and cyclohexene. The total acidity of the prepared systems plays an important role in determining the catalytic activity in the dehydrogenation of cyclohexane and cyclohexene.
Description:
Department of Applied Chemistry, Cochin University of Science and Technology