Shali, N B; Dr.Sugunan, S(Cochin University of Science and Technology, April , 2006)
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Abstract:
Catalysis is a mature field with extensive practical applications in today's society.indeed,the catalysis of petroleum refining,fine chemical synthesis and emission control demands the production of catalysts in bulk quantities.Future improvement of these well established processes is likely to be incremental.On the other hand,the continuous demand for new products will require additional novel and innovative processes.The need for pollution abatement and prevention also imposes new demands on catalysis, and new processes are periodically advanced for the control of emission of gases as well as for remediation processes such as the cleaning of underground waters. The number of problems where catalysis can have a big impact is constantly growing.In general,science stimulated by the technology has enriched the field of catalysis in a way that has had broad and lasting value.The thesis"Transition metal and rare earth metal modified sol-gel titania: a versatile catalyst for organic transformations" accounts the preparation and characterization studies of both transition metals and rare earth metals modified sol-gel titania and its applications in industrially useful organic reactions.
Description:
Department of Applied Chemistry,
Cochin University of Science and Technology
Manju, Sebastian; Dr.Mohammed Yusuff, K K(Cochin University of Science & Technology, July , 2010)
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Abstract:
Schiff base complexes of transition metal ions have played a significant role in coordination chemistry.The convenient route of synthesis and thermal stability of Schiff base complexes have contributed significantly for their possible applications in catalysis,biology,medicine and photonics.Significant variations in cataltytic activity with structure and type are observed for these complexes.The thesis deals with synthsis and characterization of transition metal complexes of quinoxaline based Schiff base ligands and their catalytic activity study.The Schiff bases synthesized in the present study are quinoxaline-2-carboxalidine-2-amino-5-methylphenol,3-hydroxyquinoxaline-2-carboxalidine-2-amino-5-methylphenol,quinoxaline-2-aminothiophenol.They provide great structural diversity during complexation.To the best of our knowledge, the transition metal complexes of quinoxaline based Schiff bases are poorly utilised in academic and industrial research.
Description:
Dept.of Applied Chemistry,Cochin University of Science and Technology
Sreesha, Sasi; Dr.Prathapachandra Kurup, M R(Cochin University of Science & Technology, October , 2008)
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Abstract:
Metallo-organic chemistry,incorporating the frontiers of both inorganic and organic chemical aspects,is a topic of utility concern.The first exploration of coordinated metal complexes dates back to the ninettenth century,during the days of Alfred Werner.Thereafter,inorganic chemistry witnessed a great outflow of coordination compounds,with unique structural characteristics and diverse applicatons.The diversity in structures exhibited by the coordination complexes of multidentate ligands have led to their usage as sensors,models for enzyme mimetic centers,medicines etc.The liganda chosen are of prime importance in determining the properties of coordination compounds.Schiff bases are compounds obtained by the condensation of an aidehyde or ketone with an amine.The chemical properties of Schiff bases and their complexes are widely explored in recent years owing to their pharmacological activity,their catalytic activities and so on.On the other hand pseudohalides like azide and thiocyanate are versatile candidates for the construction of dimeric or polymeric complexes having excellent properties and diverse applications.So a combination of the Schiff bases and the pseudohalogens for the synthesis of metal complexes can bring about interesting results.An attempt into this area is the besis of this Ph.D theis.
Description:
Department of Applied Chemistry,
Cochln University of Science and Technology
Suja, Krishnan; Dr. Prathapachandra Kurup, M R(Cochin University of Science and Technology, June , 2008)
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Abstract:
Coordination chemistry of pentadentate 2,6-diacetylpyridine
bis(thiosemicarbazone) Schiff base ligands has been intensively studied due to the versatility of the molecular chain in order to obtain very different
geometries as well as their broad therapeutic activity. Metal complexes of
thiosemicarbazone with aldehydes and ketones have been widely reported.
But there have been fewer reports on potential pentadentate
bis(thiosemicarbazones) formed from 2,6-diacetylpyridine. Keeping these in
view, we have synthesized four bis(thiosemicarbazone) systems with
2,6-diacetylpyridine. In the present work, the chelating behavior of
bis(thiosemicarbazones) are studied, with the aim of investigating the
influence of coordination exerts on their conformation and or configuration, in
connection with the nature of the metal and of the counter ion. The selection
of the 2,6-diacetylpyridine as the ketonic part was based on its capability to
form polynuclear complexes with different coordination number. The doubled
armed bis(thiosemicarbazones) can coordinate to a metal centre as dianionic
ligand by losing its amide protons or it can coordinate as monoanionic ligand
by losing its amide proton from one of the thiosemicarbazone moiety or it can
also be coordinate as neutral ligand. Hence it is interesting to explore the
coordinating capabilities of these ligands whether in neutral form or anionic
form and to study the structural variations occurring in the ligands during
complexation such as change in conformation.
Description:
Department of Applied Chemistry,
Cochin university of Science and Technology
Laly, K; Dr. Prathapachandra Kurup, M R(Cochin University of Science and Technology, July , 2011)
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Abstract:
In the present work,the chelating behaviour of thiosemicarbazones of a heterocyclic diketone, 2,6-diacetylpyridine is studied,with the aim of investigating the influence coordination exerts on their conformation and /or configuration, in connection with the nature of the metal and of the counter ion.The various possibilities like unsubstitution,ring incorporation at terminal nitrogen and condensation of one of the ketone group alone have been tried for ligand selection.Mainly first row transition metals like manganese,iron,nickel,copper,zinc and cadmium are studied.Metals like cobalt also were studied but could not result in fruitful isolation of the compound due to solubility problems.Different spectroscopic and characterization techniques have been utilized to reveal the nature of the metal and the ligands in coordinated metal complex.
Description:
Department of Applied Chemistry,Cochin University of Science and Technology
Transparent diode heterojunction on ITO coated glass substrates was fabricated using p-type AgCoO2 and n-type ZnO films by pulsed laser
deposition (PLD). The PLD of AgCoO2 thin films was carried out using the pelletized sintered target of AgCoO2 powder, which was synthesized
in-house by the hydrothermal process. The band gap of these thin films was found to be ~3.89 eV and they had transmission of~55% in the
visible spectral region. Although Hall measurements could only indicate mixed carrier type conduction but thermoelectric power measurements of
Seebeck coefficient confirmed the p-type conductivity of the grown AgCoO2 films. The PLD grown ZnO films showed a band gap of ~3.28 eV,
an average optical transmission of ~85% and n-type carrier density of~4.6×1019 cm− 3. The junction between p-AgCoO2 and n-ZnO was found
to be rectifying. The ratio of forward current to the reverse current was about 7 at 1.5 V. The diode ideality factor was much greater than 2.
Philip,M P; George,K K(Department of Applied Economics, 2006)
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Abstract:
The study documents the long-term trends in financial intermediation by the principal player in Kerala’s credit system i.e., banking. The process of financial intermediation by the banking system, involving mobilization of deposits from savers and disbursal of credit to investors, is considered to be crucial in the process of economic development. The objective of the study is to explore the interrelationship between financial intermediation and economic growth in Kerala. In order to pursue this objective, the study examine, the trends in intermediation by the banking system in Kerala over a long period, the trend and pattern of bank deposits and credit in the State and Kerala’s economic growth, the trend in the growth and performance of financial intermediaries like the All India Financial Institutions, the links between banking and economic variables, and the difference in the growth trends of banking and economic variables between Kerala and India and the probable reasons for the difference
Rani, Joseph(Huthig & Wepf Verlag, Basel, April 29, 1986)
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Abstract:
Tribasic lead sulphate is tried as a practical curing agent for polychloroprene. The
cure characteristics of the compounds as well as the technical properties of the
vulcanizates show that it can act as a potential curative.
Mini, Kuriakose; Dr. Prathapachandra Kurup, M R(Cochin University of Science & Technology, December , 2006)
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Abstract:
The present work deals with the complexation of Schiff
bases of aroylhydrazides with various transition metal ions. The hydrazone
systems selected for study are capable of forming bridged polymeric structures
which is one of the fascinating subjects in the crystal engineering of coordination
polymers owing to their attractive new topologies and intriguing structural
features. Complexation with metal ions like copper, manganese, vanadium,
nickel, palladium, 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 work is presented in seven chapters and the last section deals with
summary and conclusion. The studies reveal that the aroylhydrazone systems vary
in their geometrical configuration depending on the substituents. The coordination
modes of the ligands also differ upon chelating with metal ions. One of the
hydrazone system selected for study proved that it could give rise to polymeric
metal complexes.
Description:
Dept.of Applied Chemistry,Cochin University of Science and Technology
Abhilash, S; Dr. Mohankumar, K(Cochin University of Science and Technology., December , 2007)
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The main purpose of the thesis is to improve the state of knowledge and understanding
of the physical structure of the TMCS and its short range prediction. The present
study principally addresses the fine structure, dynamics and microphysics of severe convective
storms.The structure and dynamics of the Tropical cloud clusters over Indian region is not well
understood. The observational cases discussed in the thesis are limited to the temperature
and humidity observations. We propose a mesoscale observational network along with all
the available Doppler radars and other conventional and non—conventional observations.
Simultaneous observations with DWR, VHF and UHF radars of the same cloud system will
provide new insight into the dynamics and microphysics of the clouds. More cases have to
be studied in detail to obtain climatology of the storm type passing over tropical Indian
region. These observational data sets provide wide variety of information to be assimilated
to the mesoscale data assimilation system and can be used to force CSRM.The gravity wave generation and stratosphere troposphere exchange (STE) processes
associated with convection gained a great deal of attention to modem science and meteorologist.
Round the clock observations using VHF and UHF radars along with supplementary
data sets like DWR, satellite, GPS/Radiosondes, meteorological rockets and aircrafl
observations is needed to explore the role of convection and associated energetics in detail.
Description:
Department of Atmospheric Sciences,
Cochin University of Science and Technology
Bijumon,P V; Sreedevi,Menon K; Suma,M N(Microwave and Optical Technology Letters, November 5, 2005)
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Abstract:
rectangular low-density, high-permittivity dielectric
resona or antenna (DRA) excited by T-shaped microstrip feed offering a
2:1 VSWR bandwidth of -22% at 2.975 GHz is reported. The design
methoaology and experimental results of the antenna are discussed. The
excellent gain and radiation performance of the proposed antenna
project: it as a potential candidate for telecommunication applications
Shaji,S; Abdul Rasheed,T M(Cochin University of Science and Technology, April , 2003)
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Abstract:
The present work is mainly concentrated on setting up a NIR tunable diode laser absorption (TDLA) spectrometer for high-resolution molecular spectroscopic studies. For successfully recording the high-resolution tunable diode laser spectrum, various experimental considerations are to be taken into account like the setup should be free from mechanical vibrations, sample should be kept at a low pressure, laser should be in a single mode operation etc. The present experimental set up considers all these factors. It is to be mentioned here that the setting up of a high resolution NIR TDLA spectrometer is a novel experiment requiring much effort and patience. The analysis of near infrared (NIR) vibrational overtone spectra of some substituted benzene compounds using local mode model forms another part of the present work. An attempt is made to record the pulsed laser induced fluorescence/Raman spectra of some organic compounds. A Q-switched Nd:YAG laser is used as the excitation source. A TRIAX monochromator and CCD detector is used for the spectral recording. The observed fluorescence emission for carbon disulphide is centered at 680 nm; this is assigned as due to the n, p* transition. Aniline also shows a broad fluorescence emission centered at 725 nm, which is due to the p,p* transition. The pulsed laser Raman spectra of some organic compounds are also recorded using the same experimental setup. The calibration of the set up is done using the laser Raman spectra of carbon tetrachloride and carbon disulphide. The observed laser Raman spectra for aniline, o-chloroaniline and m-chlorotoluene show peaks characteristics of the aromatic ring in common and the characteristics peaks due to the substitutuent groups. Some new peaks corresponding to low-lying vibrations of these molecules are also assigned
The present work describes the immobilization of α-amylase over well ordered mesoporous molecular sieve SBA-15 with different pore diameters synthesized by post synthesis treatment (PST) hydrothermally after reaction at 40°C. The materials were characterized by N 2 adsorption–desorption studies, small angle X-ray diffraction, scanning electron microscopy and high resolution transmission electron microscopy. Since α-amylase obtained from Bacillus subtilis has dimensions of 35 × 40 × 70 Å it is expected that the protein have access to the pore of SBA-15 (PST-120°C) with diameter 74 Å. The pore dimension is appropriate to prevent considerable leaching. The rate of adsorption of the enzyme on silica of various pore sizes revealed the influence of morphology, pore diameter, pore volume and pH.
Shyam S,Pattnaik; Dhruba C,Panda; Devi,S(Microwave and Optical Technology Letters, September 20, 2002)
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Abstract:
The mathematical formulation of empirically developed formulas Jirr the calculation of the resonant frequency of a thick-substrate
(h s 0.08151 A,,) microstrip antenna has been analyzed. With the
use qt' tunnel-based artificial neural networks (ANNs), the resonant frequency
of antennas with h satisfying the thick-substrate condition are
calculated and compared with the existing experimental results and also
with the simulation results obtained with the use of an IE3D software
package. The artificial neural network results are in very good agreement
with the experimental results
Riju C, Issac; Pramod, Gopinath; Geetha K, Varier; Nampoori, V P N; Vallabhan, C P G(American Institute of Physics, July 13, 1998)
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Abstract:
Laser-induced plasma generated from a silver target under partial vacuum conditions using the
fundamental output of nanosecond duration from a pulsed Nd:yttrium aluminum garnet laser is
studied using a Langmuir probe. The time of flight measurements show a clear twin peak
distribution in the temporal profile of electron emission. The first peak has almost the same duration
as the laser pulse while the second lasts for several microseconds. The prompt electrons are
energetic enough ('60 eV) to ionize the ambient gas molecules or atoms. The use of prompt
electron pulses as sources for electron impact excitation is demonstrated by taking nitrogen, carbon
dioxide, and argon as ambient gases.
Bindhu, C V; Harilal, S S; Achamma, Kurian; Nampoori, V P N; Vallabhan, C P G(World Scientific Publishing Company, 1998)
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Abstract:
Dual beam transient thermal lens studies were carried out in rhodamine 6G methanol solutions using 532 nm pulses from a frequency doubled Nd:YAG laser. Analysis of thermal lens signal shows the existence of different nonlinear processes like two photon absorption and three photon absorption phenomena along with one photon absorption. Concentration of the dye in the solution has been found to influence the occurrence of the different processes in a significant way.
Sreekumar, J; Nandakumaran, V M(World Scientific Publishing Company, 1990)
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Abstract:
Large amplitude local density fluctuations in a thin superfluid He film is considered. It is shown that these large amplitude fluctuations travel and behave like "quasi-solitons" under collision, even when the full nonlinearity arising from the Van der Waals potential is taken into account.
Bindu, G; Santhosh John, Abraham; Anil, Lonappan; Vinu, Thomas; Anandan, C K; Mathew, K T(International Journal of Cancer Research, 2006)
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Abstract:
Despite its recognized value in detecting and characterizing breast disease, X-ray
mammography has important limitations that motivate the quest for alternatives to augment
the diagnostic tools that are currently available to the radiologist. The rationale for pursuing
electromagnetic methods are based on the significant dielectric contrast between normal
and cancerous breast tissues, when exposed to microwaves. The present study analyzes
two-dimensional microwave tomographic imaging on normal and malignant breast tissue
samples extracted by mastectomy, to assess the suitability of the technique for early
detection ofbreast cancer. The tissue samples are immersed in matching coupling medium
and are illuminated by 3 GHz signal. 2-D tomographic images ofthe breast tissue samples
are reconstructed from the collected scattered data using distorted Born iterative method.
Variations of dielectric permittivity in breast samples are distinguishable from the obtained
permittivity profiles, which is a clear indication of the presence of malignancy. Hence
microwave tomographic imaging is proposed as an alternate imaging modality for early
detection ofbreast cancer.
Mohammed Yusuff, K K; Varsha, Gopalakrishnan; Arun, Vasudevan; Robinson, P P; Manju, Sebastian; Digna, Varghese; Leeju, P; Jayachandran, V P(Elesvier,Tetrahedron Letters (2010), February 15, 2010)
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Abstract:
An efficient one-pot synthesis of two new heterocyclic perimidines 4-(2,3-dihydro-1H-perimidin-2-yl)-2-methoxyphenol and
2-(quinoxalin-2-yl)-2,3-dihydro-1H-perimidine in good yields is presented. This methodology provides a simple, straightforward synthetic
route to these interesting classes of heterocycles. Crystal structure, solvatochromism and antibacterial activity of these organic compounds
are discussed.