Varughese,Philip; Prathapachandra Kurup, M R(Dept. of Applied Chemistry, July , 2004)
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Abstract:
The study deals with structural and spectral investigations of transition metal complexes of di-2-pyridyl ketone N(4),N(4)-disubstituted thiosemicarbazones. The main objective and scope of the work deals with di-2-pyridyl ketone N(4),N(4)-disubstituted thiosemicarbazones are quardridentate NNNS donor ligands. To chosen this ligand for study because, the ligands are prepared and characterized for the first time, since there are two pyridyl nitorgens, dimmers and polymers of complexes may result leading to interesting structural aspects. The work includes the preparation of the thiosemicarbzones and their structural and spectral studies, synthesis and spectral characterization of complexes of copper(II),,nickel(II),manganese(II), dioxovanadium(V),cobalt(III),zinc(II),cadmium(II) of the ligand HL, synthesis and spectral characterization of complexes of copper(II),manganese(II), of the ligand HL and the development of X-ray quality crystals and its X-ray diffraction studies. The structural characterization techniques are elemental analysis, conductivity measurements, magnetic measurements, electronic spectroscopy, H NMR spectroscopy, Infrared spectroscopy and X-ray crystallography.
Bessy Raj, B N; Dr.Prathapachandra Kurup,M R(Cochin University of Science and Technology, February , 2009)
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Abstract:
The present work deals with the complexation of Schiff
bases of aroylhydrazines with various transition metal ions. The hydrazone
systems selected for study have long 7I:-delocalized chain in the ligand molecule
itself, which get intensified due to metal-to-ligand or ligand-to-metal charge
transfer excitations upon coordination. Complexation with metal ions like copper,
nickel, cobalt, manganese, iron, zinc and cadmium are tried. Various spectral
techniques are employed for characterization. The structures of some complexes
have been well established by single crystal X-ray diffraction studies. The nonIinaer
optical studies of the ligands and complexes synthesized have been studied
by hyper-Rayleigh scattering technique.The work is presented in seven chapters and the last one deals with
summary and conclusion. One of the hydrazone system selected for study proved
that it could give rise to polymeric metal complexes. Some of the copper, nickel,
zinc and cadmium complexes showed non-linear optical activity. The NLO
studies of manganese and iron showed negative result, may be due to the inversion
centre of symmetry within the molecular lattice.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology
Rajive, Tomy M; Dr.Jayalekshmi, S(Cochin University Of Science And Technology, July 20, 2012)
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Abstract:
The main challenges in the deposition of cathode materials in thin film form are
the reproduction of stoichiometry close to the bulk material and attaining higher
rates of deposition and excellent crystallinity at comparatively lower annealing
temperatures. There are several methods available to develop stoichiometric thin
film cathode materials including pulsed laser deposition; plasma enhanced
chemical vapor deposition, electron beam evaporation, electrostatic spray
deposition and RF magnetron sputtering. Among them the most versatile
method is the sputtering technique, owing to its suitability for micro-fabricating
the thin film batteries directly on chips in any shape or size, and on flexible
substrates, with good capacity and cycle life. The main drawback of the
conventional sputtering technique using RF frequency of 13.56MHz is its lower
rate of deposition, compared to other deposition techniques A typical cathode
layer for a thin film battery requires a thickness around one micron. To deposit
such thick layers using convention RF sputtering, longer time of deposition is
required, since the deposition rate is very low, which is typically 10-20 Å/min.
This makes the conventional RF sputtering technique a less viable option for
mass production in an economical way.
There exists a host of theoretical and experimental evidences and results that
higher excitation frequency can be efficiently used to deposit good quality films
at higher deposition rates with glow discharge plasma. The effect of frequencies
higher than the conventional one (13.56MHz) on the RF magnetron sputtering
process has not been subjected to detailed investigations. Attempts have been
made in the present work, to sputter deposit spinel oxide cathode films, using
high frequency RF excitation source. Most importantly, the major challenge faced by the thin film battery based on the LiMn2O4 cathode material is the poor capacity retention during charge discharge cycling. The major causes for the capacity fading reported in LiMn2O4cathode materials are due to, Jahn-Teller distortion, Mn2+ dissolution into the electrolyte and oxygen loss in cathode material during cycling. The work discussed in this thesis is an attempt on overcoming the above said challenges and developing a high capacity thin film cathode material.
Description:
Division for Research in Advanced Materials
Department of Physics
Cochin University of Science and Technology
Sivakumar,S; Prathapachandra Kurup, M R(Department of Applied Chemistry, 2002)
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Abstract:
The primary aim of these investigations was to probe the spectroscopic, electrochemical, biological and single crystal X-ray diffraction studies of some selected transition metal complexes of 4N-monosubstituted thiosemicarbazones. Transition metal complexes with thiosemicarbazones exhibit a wide range of stereochemistries and possess potential biological activity. Metal complexes of thiosemicarbazones are proved to have improved pharmacological and therapeutic effects. The studies are conducted to bring about a fair understanding of the structure activity relationship and to develop certain effective and economical metal-based antimicrobial agents. Study showed that the thiosemicarbazones have antibacterial, antiviral and antiproliferative properties and hence used against tuberculosis, leprosy, psoriasis, rheumatism, trypanosomiasis and coccidiosis. Certain thiosemicarbazones showed a selective inhibition of HSV and HIV infections. The insolubility of most thiosemicarbazones in water causes difficulty in the oral administration in clinical practice. Transition metal complexes are found to have more activity than uncombined thiosemicarbazones. They exhibit a variety of denticity and can be varied by proper substitution. The stereochemistry assumed by the thiosemicarbazones during the coordination with transition metal ions depends on the factors such as preparative conditions and availability of additional bonding site in the ligand moiety and charge of the ligand. The resulting complexes exhibited a wide range of stereochemistries and have biomimic activity and potential application as sensors
Sivakumar,S; Prathapachandra Kurup, M R(Department of Applied Chemistry, 2002)
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Abstract:
The primary aim of these investigations was to probe the spectroscopic, electrochemical, biological and single crystal X-ray diffraction studies of some selected transition metal complexes of 4N-monosubstituted thiosemicarbazones. Transition metal complexes with thiosemicarbazones exhibit a wide range of stereochemistries and possess potential biological activity. Metal complexes of thiosemicarbazones are proved to have improved pharmacological and therapeutic effects. The studies are conducted to bring about a fair understanding of the structure activity relationship and to develop certain effective and economical metal-based antimicrobial agents. Study showed that the thiosemicarbazones have antibacterial, antiviral and antiproliferative properties and hence used against tuberculosis, leprosy, psoriasis, rheumatism, trypanosomiasis and coccidiosis. Certain thiosemicarbazones showed a selective inhibition of HSV and HIV infections. The insolubility of most thiosemicarbazones in water causes difficulty in the oral administration in clinical practice. Transition metal complexes are found to have more activity than uncombined thiosemicarbazones. They exhibit a variety of denticity and can be varied by proper substitution. The stereochemistry assumed by the thiosemicarbazones during the coordination with transition metal ions depends on the factors such as preparative conditions and availability of additional bonding site in the ligand moiety and charge of the ligand. The resulting complexes exhibited a wide range of stereochemistries and have biomimic activity and potential application as sensors.
Abdul,Rashid K K; Dr.Krishnan Nambisan, P N; Dr.Jacob, Chacko(Cochin University of Science and Technology, November , 1986)
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Abstract:
This thesis deals with the studies on the synthesis and characterisation of the complexes of embelin with manganese (II), cobalt(II), nickel (II), copper (II), zinc (II), cadmium (II), chromium (III), iron (III) lanthanum(III), praseodymium (III) neodymium (III) Samarium (III), gadolinium (III) dysprosium (III), yttrium (III) thorium (IV) and uranium (VI). Elemental analysis as well as spectral, thermal and magnetic data were used to ascertain the composition of the complexes and to establish the structures of the metal complexes. Wherever possible, the electronic spectra and magnetic data were used to predict the stereochemistry of the complexes.The thesis is divided into four chapters.
Description:
Division of Chemical
Oceanography, School of Marine Science, Cochin University of Science and Technology
Binitha, N N; Dr.Sugunan, S(Cochin University of Science and Technology, October , 2006)
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Abstract:
Green chemistry boots eco-friendly,natural clays as catalysts in the chemical as well as in the pharmaceutical industry.Industry demands thermal stability,mechanical strength etc for the catalyst and there the modification methods becomes important.Pillaring tunes clays as efficient catalytic templates for shape selective organic synthesis.Here pillared clays are used as promising alternatives for the environmentally hazardous homogeneous catalysts in some industrially important Friedel-Crafts alkylation reactions of arenes with lower alchohols and higher olefins.The layer structure is enhanced upon pillaring and allows the nanocomposite formation with polyaniline to develop today’s nanoscale diameter devices.Present work gives an entry of pillared clays to the world of conducting composite nanofibers.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology
Antony,G; Dr.Ranganathan, N(Cochin University of Science and Technology, April , 1986)
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Abstract:
The study evolved from the basic
premise that the existing distribution
structure is not adequate or adaptive to
meet the needs of the expanding manufacturing
sector and the emerging mass market.
The hypothised causes of the problem are
the following: marketing channels
are not used for strategy differentiation
by manufacturers: there are too many intermediaries
in the channels; the distributive
institutions are not adaptive; and there
is very little control over the flow of
products through the channels. These
assumptions about the causes of the problem
have been translated into specific
hypotheses and tested with data. Empirical
analysis, while supporting some of these
hypotheses, challenges certain widely held
notions. The ensuing summary presents the
important findings, in the sequence in
which they are discussed in the study.
Description:
School of Management Studies,Cochin University of Science and Technology
Neson, Varghese; Dr.Syamaprasad,U(Cochin University of Science and Technology, May 2, 2012)
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Abstract:
This thesis Entitled Studies on transport and magnetic properties of nano particle doped mgb2 superconductor for technological applications.The thesis ahead focuses on the establishment of enhanced superconducting properties in bulk MgB2 via nano particle doping and its conversion into mono/multifilamentary wires. Further, an attempt has also been made to develop prototypes of MgB2 coil and conduction cooled current lead for technological applications. The thesis is configured into 6
chapters. The opening chapter gives an idea on the phenomenon of superconductivity, the various types of superconductors and its applications in different fields. The second chapter is an introduction on MgB2 superconductor and its relevance which includes crystal and electronic structure, superconducting mechanism, basic superconducting properties along with its present international status. The third chapter provides details on the preparation and characterization techniques followed through out the study on MgB2. Fourth chapter discusses the effect of processing temperature and chemical doping using nano sized dopants on the superconducting properties of MgB2• Fifth chapter deals with the optimization of processing parameters and novel preparation techniques for wire fabrication. Sixth chapter furnishes the preparation of multifilamentary wires with various filament configurations, their electromechanical properties and it also incorporates the development of an MgB2 coil and a general purpose conduction cooled current lead.
Description:
Applied Super conductivity Group,Material science and technology division,National Institute for Interdisciplinary Science and Technology
Pramod, Gopinath; Dr.Nampoori,V P N(Cochin University of Science and Technology, April , 2006)
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Abstract:
Developments in laser technology over the past few years have made it possible to do
experiments with focused intensities of IO"-102' Wcm'z. Short-pulse high-intensity
lasers are able to accelerate protons and heavier ions to multi-MeV energies during
their interaction with solid targets, gas jets and clusters. When such a laser radiation
is focused at the intensity above 10” Wcm'2, local electric field strength will be
almost equivalent to that within an atom. Hence, new nonlinear optical phenomena
will be expected in the field of light matter interaction. Most of the research in the
material interaction using high power lasers, especially related to plasma interaction,
has been directed to the short pulse x-ray generation- Nanosecond laser interactions
with solid targets also generate plasmas which emit radiation mainly in the optical
region, the understanding of which is far from satisfactory. This thesis deals with a
detailed study of some of the dynamical processes in plasmas generated by
nanosecond and femtosecond lasers
Description:
lntemational School of Photonics
Cochin University of Science and Technology
Sheena, Mathew; Dr.Poulose Jacob, K(Cochin University of Science and Technology, June , 2008)
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Abstract:
Internet today has become a vital part of day to day life, owing to the
revolutionary changes it has brought about in various fields. Dependence on
the Internet as an information highway and knowledge bank is exponentially
increasing so that a going back is beyond imagination. Transfer of critical
information is also being carried out through the Internet. This widespread use
of the Internet coupled with the tremendous growth in e-commerce and m-commerce
has created a vital need for infonnation security.Internet has also become an active field of crackers and intruders. The
whole development in this area can become null and void if fool-proof security
of the data is not ensured without a chance of being adulterated. It is, hence a
challenge before the professional community to develop systems to ensure
security of the data sent through the Internet.Stream ciphers, hash functions and message authentication codes play
vital roles in providing security services like confidentiality, integrity and
authentication of the data sent through the Internet. There are several ·such
popular and dependable techniques, which have been in use widely, for quite a
long time. This long term exposure makes them vulnerable to successful or
near successful attempts for attacks. Hence it is the need of the hour to
develop new algorithms with better security.Hence studies were conducted on various types of algorithms being
used in this area. Focus was given to identify the properties imparting security
at this stage. By making use of a perception derived from these studies, new algorithms were designed. Performances of these algorithms were then
studied followed by necessary modifications to yield an improved system
consisting of a new stream cipher algorithm MAJE4, a new hash code JERIM-
320 and a new message authentication code MACJER-320. Detailed analysis
and comparison with the existing popular schemes were also carried out to
establish the security levels.The Secure Socket Layer (SSL) I Transport Layer Security (TLS)
protocol is one of the most widely used security protocols in Internet. The
cryptographic algorithms RC4 and HMAC have been in use for achieving
security services like confidentiality and authentication in the SSL I TLS. But
recent attacks on RC4 and HMAC have raised questions about the reliability
of these algorithms. Hence MAJE4 and MACJER-320 have been proposed as
substitutes for them. Detailed studies on the performance of these new
algorithms were carried out; it has been observed that they are dependable
alternatives.
Description:
Department of Computer
Science, Cochin University of Science and Technology