Sreedevi, M G; Dr. Balchand, A N(Cochin University of Science and Technology, February , 2007)
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Abstract:
This thesis attempts to gain insight on the mathematical approach to estuarine
oceanographic systems; also to closely understand the governing processes in the
estuarine environment as well as in the adjoining river reaches.
The main aim was to conduct pollution routing for tropical estuarine environment
namely, for the Cochin estuary. In this context, attempts have been made to apply,
verify and validate the application of models, pre- prepared with necessary
modifications to suit the area of interest by use of RIVMIX and WASP tools.
Finally the thesis concludes by highlighting the advantages and limitations in
modelling water bodies and concurrentlysimulates most of the possible scenarios
within the purview of this work.
Description:
Department of Physical Oceanography,
Cochin University of Science and Technology
This 'study' deals with a preliminary study of automatic beam
steering properly in conducting polyaniline . Polyaniline in its undoped and
doped .state was prepared from aniline by the chemical oxidative polymerization
method. Dielectric properties of the samples were studied at S-band
microwave frequencies using cavity perturbation technique. It is found that
undoped po/vanihne is having greater dielectric loss and conductivity contpared
with the doped samples. The beam steering property is studied using
a perspex rod antenna and HP 85/OC vector network analyzer. The shift in
the radiated beam is studied for different do voltages. The results show that
polyaniline is a good nutterial far beam steering applications.
Sugunan, S; Binitha, N N(Journal of Applied Polymer Science,Wiley InterScience, March 16, 2007)
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Abstract:
In situ polymerization of aniline is done
inside the pillared clay matrix. The nonswellable pillared
clay confined matrix allows efficient polymerization that
leads to nanofibrous morphology. As a result high polymer
order and crystallinity is attained and is evident from
XRD patterns. The strong interaction between the clay
layers and polyaniline (PANI) is understood from FTIR and DRS spectra. Additionally these analytical results suggest that the prepared PANI is in the doped state. The
PANI/pillared clay nanocomposite formation gives additional
thermal stability to the polymer backbone and is clear from the DTG curves.
Latha Unnikrishnan; Devadasan,K(Central Institute of Fisheries Technology, 2006)
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Abstract:
Polycyclic Aromatic Hydrocarbons and other toxic compounds from industrial effluents are noted for their high potency for skin, lung, bladder and gastrointestinal cancers. Increased industrialization, and population growth led to greater production of wastes, Pesticides and PAHs have received attention due to their carcinogenic effects. The main objectives of the study were; to collect base line data on the concentration of PAHs in seawater and sediment from the west coast of India, the concentration of PAHs in certain species of fishes, the comparative levels of PAHs in fish, the influence of sediment characteristics on the concentration of PAH in sediment, changes in PAH concentration in water, sediment and fish, to provide a base line concentration of trace metals in water, sediment and fish, the seasonal changes in content of selected trace metals in water, sediment and fish from the west coast of India. The present study revealed that a predominance of silt and clay at all stations in the off Cochin area. The study has provided comprehensive information available to date for PAHs in seawater, sediment and fishes from the west cost of India especially from the Quilon to Mangalore region.
Saji, John K; Dr.Girish Kumar, K(Cochin University of Science and Technology, May 3, 2004)
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Abstract:
As the application of polymeric complexes is enormous, there
exists a continuing interest in the synthesis and characterization of
these complexes. The synthetic and characterization parts are very
important in an academic point of view. Further in an application
point of view also polymeric ligands/complexes are gaining
attention.The thesis is divided in to six chapters, in which the first
chapter gives an introduction along with a brief review on polymeric ligands/ complexes. The second chapter explains the different
procedure adopted for the whole work along with the details of the
reagents/ instruments used. The third chapter gives a report of the
detailed study regarding the synthesis and characterization of
eighteen complexes. While the fourth chapter is a report of the ion
removal studies using three polymeric ligands, the fifth chapter
explains the development of a polymeric complex as ion selective
electrode material for the fabrication of a CC ion selective electrode.
The sixth chapter presents the summary and tables, figures and
references are given separately at the end.
Description:
Department of Applied Chemistry, Cochin University of Science
and Technology
Anoop Anand,K; Dr.Rani,Joseph(Cochin University of Science & Technology, December , 2006)
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Abstract:
The current research investigates the possibility of using single walled carbon
nanotubes (SWNTs) as filler in polymers to impart several properties to the matrix
polymer. SWNTs in a polymer matrix like poly(ethylene terephthalate) induce
nucleation in its melt crystallization, provide effective reinforcement and impart
electrical conductivity. We adopt a simple melt compounding technique for
incorporating the nanotubes into the polymer matrix. For attaining a better dispersion
of the filler, an ultrasound assisted dissolution-evaporation method has also been tried.
The resulting enhancement in the materials properties indicates an improved
disentanglement of the nanotube ropes, which in turn provides effective matrix-filler
interaction. PET-SWNT nanocomposite fibers prepared through melt spinning
followed by subsequent drawing are also found to have significantly higher mechanical
propertiesas compared to pristine PET fiber.SWNTs also find applications in composites based on elastomers such as natural
rubber as they can impart electrical conductivity with simultaneous improvement in the
mechanical properties.
Description:
Department of Polymer Science and Rubber Technology,
Cochin University of Science and Technology
Anantharaman, M R; Joy, P A; Philip, Kurian; Prema, K H(Taylor & Francis, January 30, 2008)
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Abstract:
Fine (approximately 18 nm) particles of nickel ferrite were
synthesized by the sol-gel technique, and their structural properties
were evaluated by X-ray diffraction. Neoprene-based rubber ferrite
composites were prepared by incorporating these nickel ferrite powders
in the rubber matrix according to a specific recipe. The cure
characteristics were analyzed, and the samples were molded into
particular shapes whose properties were determined according to
ASTM standards. Magnetization studies were carried out using a
Vibrating Sample Magnetometer. This study indicates that neoprene
rubber-based flexible magnets with desired magnetic properties
and appropriate mechanical properties can be prepared by
incorporating an adequate amount of nanoscale nickel ferrite particles
within the rubber matrix
Description:
Polymer-Plastics Technology and Engineering, 47: 137–146, 2008
Rani, Joseph(Gordon and Breach Science Publishers, Inc., November 28, 1986)
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Abstract:
Polymer-solvent interaction parameters for the blends of natural rubber (NR) with
styrene-butadiene rubber (SBR) and polybutadiene rubber ( BR) are calculated using
the Flory-Rehner equation by equating the network density of the vulcanizates in
two solvents.
Poulose Jacob,K; Rekha, James K; Babita, Jose R; Shahana, T K; Sreela Sasi(IEEE, 2007)
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Abstract:
In a sigma-delta analog to digital (A/D) As most of the sigma-delta ADC applications require
converter, the most computationally intensive block is decimation filters with linear phase characteristics,
the decimation filter and its hardware implementation symmetric Finite Impulse Response (FIR) filters are
may require millions of transistors. Since these widely used for implementation. But the number of FIR
converters are now targeted for a portable application, filter coefficients will be quite large for implementing a
a hardware efficient design is an implicit requirement. narrow band decimation filter. Implementing decimation
In this effect, this paper presents a computationally filter in several stages reduces the total number of filter
efficient polyphase implementation of non-recursive coefficients, and hence reduces the hardware complexity
cascaded integrator comb (CIC) decimators for and power consumption [2].
Sigma-Delta Converters (SDCs). The SDCs are The first stage of decimation filter can be
operating at high oversampling frequencies and hence implemented very efficiently using a cascade of integrators
require large sampling rate conversions. The filtering and comb filters which do not require multiplication or
and rate reduction are performed in several stages to coefficient storage. The remaining filtering is performed
reduce hardware complexity and power dissipation. either in single stage or in two stages with more complex
The CIC filters are widely adopted as the first stage of FIR or infinite impulse response (IIR) filters according to
decimation due to its multiplier free structure. In this the requirements. The amount of passband aliasing or
research, the performance of polyphase structure is imaging error can be brought within prescribed bounds by
compared with the CICs using recursive and increasing the number of stages in the CIC filter. The
non-recursive algorithms in terms of power, speed and width of the passband and the frequency characteristics
area. This polyphase implementation offers high speed outside the passband are severely limited. So, CIC filters
operation and low power consumption. The polyphase are used to make the transition between high and low
implementation of 4th order CIC filter with a sampling rates. Conventional filters operating at low
decimation factor of '64' and input word length of sampling rate are used to attain the required transition
'4-bits' offers about 70% and 37% of power saving bandwidth and stopband attenuation.
compared to the corresponding recursive and Several papers are available in literature that deals
non-recursive implementations respectively. The same with different implementations of decimation filter
polyphase CIC filter can operate about 7 times faster architecture for sigma-delta ADCs. Hogenauer has
than the recursive and about 3.7 times faster than the described the design procedures for decimation and
non-recursive CIC filters.
Description:
Electron Devices and Solid-State Circuits, 2007. EDSSC 2007. IEEE Conference on
Dasan,E V; Chandrasekaran, M(Department of Biotechnology, Faculty of Science, January , 2002)
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Abstract:
Phosphate (Pi) is one among the most important essential residues in maintenance and inheritance of life, with far diverse physiological role as structural, functional and energy transduction. Phosphate accumulation in wastewaters containing run off of fertilizers and industrial discharges is a global problem that results in algal blooms in bays, lakes and waterways. Currently available methods for removing phosphates from wastewater are based primarily on polyP accumulation by the activated sludge bacteria. PolyP plays a critical role in several environmental and biotechnological problems. Possible relation of interaction between polyP accumulation phenomenon, the low biomass, low Pi uptake, and varying results obtained in response to the impact of sodium chloride, pH, temperature, various inorganic salts and additional carbon sources studied, are all intriguing observations in the present investigation. The results of the present study have evidenced very clearly the scope for potential strains of bacteria from both sea water and marine sediments which could be exploited both for Pi removal in wastewater released by industries and intensive aquaculture practices in to the aquatic environment as well as to harness the potential strains for industrial production of polyP which was wide range of applications.
Saisy, Esthappan K; Dr.Rani,Joseph(Cochin University of Science and Technology, May , 2012)
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Abstract:
PP has been getting much attention over the years because it is a very
durable polymer commonly used in aggressive environments including
automotive battery casings, fuel containers etc. They are used to make bottles,
fibers for clothing, components in cars etc. However, it has some shortcomings
such as low dimensional and thermal stability. Materials such as metal oxides
with sizes of the order 1–50 nm have received a great deal of attention because
of their versatile applications in polymer/ inorganic nanocomposites,
optoelectronic devices, biomedical materials, and other areas. They are stable
under harsh process conditions and also regarded as safe materials to human
beings and animals. In the present investigation, PP is modified by incorporating metal oxide
nanoparticles such as ZnO and TiO2 by simple melt mixing method. Melt
spinning method was used to prepare PP/metal oxide nanocomposite fibers.
Various studies have been carried out on these composites and fibers.
In the first part of the study, ZnO nanoparticles were prepared from
ZnCl2 and NaOH in presence of chitosan, PVA, ethanol and starch. This is a
simple and inexpensive method compared to other methods. Change in
morphology and particle size of ZnO were studied. Least particle size was
obtained in chitosan medium. The particles were characterized by using XRD,
SEM, TEM, TGA and EDAX. Antibacterial properties of ZnO prepared in
chitosan medium (NZO) and commercial zinc oxide (CZO) were evaluated
using a gram positive and a gram negative bacteria
Description:
Department of Polymer Science and Rubber Technology
Cochin University of Science and Technology
Girish Kumar,K; Saji John,Konnully; Remalakshmy,Poduval(Department of Applied Chemistry, April 2, 2005)
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Abstract:
A set of six new polystyrene anchored metal
complexes have been synthesized by the reaction of the
metal salt with the polystyrene anchored Schiff base of
vanillin. These complexes were characterized by elemental
analyses, Fourier transform infrared spectroscopy, diffuse
reflectance studies, thermal studies, and magnetic susceptibility
measurements. The elemental analyses suggest a
metal : ligand ratio of 1 : 2. The ligand is unidentate and
coordinates through the azomethine nitrogen. The Mn(II),
Fe(III), Co(II), Ni(II), and Cu(II) complexes are all paramagnetic
while Zn(II) is diamagnetic. The Cu(II) complex is
assigned a square planar structure, while Zn(II) is assigned
a tetrahedral structure and Mn(II), Fe(III), Co(II), and Ni(II)
are all assigned octahedral geometry. The thermal analyses
were done on the ligand and its complexes to reveal their
stability. Further, the application of the Schiff base as a
chelating resin in ion removal studies was investigated. The
polystyrene anchored Schiff base gave 96% efficiency in the
removal of Ni(II) from a 20-ppm solution in 15 min, without
any interference from ions such as Mn(II), Co(II), Fe(III),
Cu(II), Zn(II), U(VI), Na , K , NH4
, Ca2 , Cl , Br , NO3
,
NO2
,and CH3CO2
. The major advantage is that the removal
is achieved without altering the pH.
Sheelu,Varghese; Bake,Shameena; Lakshmy,P S; Biju,M P; Eswar Shankar,P N; Paulose,C S; Oommen,V Oommen(Department of Bio Technology, August 27, 2001)
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Abstract:
The effects of feeding of 6-propyllhiouracil (6-I'fU) and potyunsaturatcd fatty acids (I'UFA) independently and ill
combination and administration (ip) of a single close of Iriiodothyronine (I',) (2.51ig/IOOg body wl) along with feeding of 6-
PTU and PUFA were studied in cal brain. Dopamine (DA), 5-hydroxytryplophan (5-IIl'I'), serolouin (5-Ill), 5-hydioxy indole
acetic acid (5-111AA), norepinephrine (NF) :uul ceinephrinn (I?I'l) contenls were assayed in the hypothalannls and ccrc
bral cortex regions. It was found that 6-P"l'U Iccding resulted in decrease in dopamine, 5-III', 5 II I I' and 5 IIiAA in both
regions. In animals fed wills PUFA followed by adnliuislralion of T,. the I)A level was found normal.