Prathapachandra Kurup, M R; Jessy, Emmanuel; Sithambaresan, M(November 3, 2011)
[+]
[-]
Abstract:
The title compound, C11H9N3O2, exists in the E conformation
with respect to the azomethane C N bond, and has the keto
form. There are two independent molecules in the asymmetric
unit and each of these features a slight slanting of the pyridine
and furan rings, which form a dihedral angle of 14.96 (10) in
one of the molecules and 5.53 (10) in the other. The crystal
structure is stabilized by N—H O and N—H N hydrogen
bonds, weak C—H O and C—H N hydrogen bonds and
C—H interactions and – interactions [shortest
centroid–centroid distance = 3.7864 (15) A ° ].
Vineetha K.A; Dr. Ajitha, K(Cochin University of Science and Technology, November 6, 2015)
[+]
[-]
Abstract:
िशक्षा एवं जागरण के फलस्वरूप आधुिनक समाज म नारी िविभ क्षेतर्ो म
उपलिब्धयाँ हािसल करने लगी है| वह हर क्षेतर् म पुरुष के साथ कंधे से कन्धा िमलाकर
आगे बढ़ने की कोिशश कर रही है| पर िपतृसा भी हर युग म अपना वचर्स्व बनाये
रखने की कोिशश करती आ रही है| वह ी को हमेशा दूसरे दज के नागिरक के रूप म
मानती है| वह नारी की गित पर रोक लगाने का पर्यास करती रहती है क्यिक उसके
स्वाथ की पूित के िलए यह अिनवायर् है| आज़ादी के इतने वषर् बीतने पर भी नारी की
िस्थित म अनेकानेक िवडंबनाय िदखाई पड रही ह| भूमंडलीकरण भी उसे यौन िसबंल
के रूप म पिरवितत कर रहा है|
Aneeshkumar, B; Pramod, Gopinath; Jayan,Thomas; Vallabhan, C P G; Nampoori, V P N; Radhakrishnan, P(Elsevier, June , 2004)
[+]
[-]
Abstract:
The nanosecond optical limiting characteristics of sandwich-type neodymium diphthalocyanine in a co-polymer matrix of polymethyl methacrylate (PMMA) and methyl-2-cyanoacrylate have been studied for the first time. The measurements were performed using 9 ns laser pulses generated from a frequency-doubled Nd:YAG laser at 532 nm wavelength. The optical limiting performance of neodymium diphthalocyanine in co-polymer host was studied at different linear transmission. Laser damage threshold was also measured for the doped and undoped co-polymer samples. The optical limiting response is attributed to reverse saturable absorption which is due to excited-state absorption.
Ramakrishnan, R; Dr. Manoj Raama Varma; Dr. J. D. Sudha(Cochin University of Science and Technology, July 25, 2014)
[+]
[-]
Abstract:
Recent developments on nanostructured conducting polymer-inorganic
composites systems have receieved considerable research interest owing to their
unique synergestic properties compared with their individual bulk counter parts
which make them promising candidates for a broad spectrum of high technological
applications such as in energy conversion, electronic devices, storage, sensors,
actuators, memory devices, and biomedical devices. Nanostructured conducting
polymers possess unique features such as high specific surface area, high charge
carrier concentration, high electrical conductivity, high mechanical flexibility, light
weight, solution processability and printability over a large area which make them
favourable for their high tech applications. Among the conducting polymers,
polyanilline, poly(3,4-ethylene dioxy thiophene), poly(N-vinylcarbzole) are
receiving much importance due to their low cost, environmental stability and
unique doping mechanism. Conversely, semiconducting inorganic metal oxide such
as zinc oxide and titania nanomaterials have emerged as an area of intense research
interest motivated by their potential applications in electronics, non-linear optics,
and magnetic devices due to their low band gap, small crystalline size and unique
opto-electronic properties. In this perspective, studies on the development and
applications of semiconducting polymer-inorganic metal oxide nanocomposite are
interesting since it is expected to exhibit synergistic properties arising from the
molecular level mixing of conducting polymer and inorganic counter parts.
Aswathy, K V; Dr.Rani,Joseph(Cochin University of Science & Technology, September , 2007)
[+]
[-]
Abstract:
Various synthesis routes have been developed in recent years for the
preparation of nanoparticles. One of those methods is polymer induced
crystallization. The first objective of the present work was to prepare nano ZnO
powder by polymer induced crystallization in chitosan solution and to
characterize the material using different techniques like TEM, SEM, XRD,
FTLR, UV spectroscopy, TGA, DSC etc.The second object of the study is to prepare composites using nano ZnO. It
has been undertaken to explore the potential of nano ZnO as reinforcement in
engineering as well as commodity thermoplastics to widen their application
spectra. We selected three engineering thermoplastics like [poly ethylene
terephthalate, polyamide 6, and polycarbonate] and three commodity plastics
like [polypropylene, high density polyethylene, and polystyrene] for the study.
To date one of the few disadvantages associated with nanoparticle incorporation
has concerned toughness and impact performance. Modification of polymers
could reduce impact performance. The present study also focused on whether
nano ZnO can act as a modifier for thennoplastics, without sacrificing their
impact strength.
Description:
Department of Polymer Science and Rubber Technology,
Cochin University of Science and Technology
Sasidharan, K K; Dr. Thomas, Kurian; Dr. Rosamma, Alex(Cochin University of Science And Technology, February , 2014)
[+]
[-]
Abstract:
Sensitisation of natural rubber latex by addition of a small quantity of
an anionic surfactant prior to the addition of a coacervant results in quick
coagulation. The natural rubber prepared by the novel coagulation method
shows improved raw rubber characteristics, better cure characteristics in
gum and carbon black filled compounds and improved mechanical
properties as compared to the conventionally coagulated natural rubber.
Compounds based on dried masterbatches prepared by the incorporation of
fluffy carbon black in different forms of soap sensitised natural rubber
latices such as fresh latex, preserved field latex, centrifuged latex and a
blend of preserved field latex and skim latex show improved cure
characteristics and vucanizate properties as compared to an equivalent
conventional dry rubber-fluffy carbon black based compound.
The latex masterbatch based vulcanizates show higher level of
crosslinking and better dispersion of filler. Vulcanizates based on fresh
natural rubber latex- dual filler masterbatches containing a blend of carbon
black and silica prepared by the modified coagulation process shows very
good mechanical and dynamic properties that could be correlated to a low
rolling resistance. The carbon black/silica/nanoclay tri-filler - fresh natural
rubber latex masterbatch based vulcanizates show improved mechanical
properties as the proportion of nanoclay increased up to 5 phr.
The fresh natural rubber latex based carbon black-silica masterbatch/
polybutadiene blend vulcanizates show superior mechanical and dynamic
properties as compared to the equivalent compound vulcanizates prepared
from the dry natural rubber-filler (conventional dry mix)/polybutadiene blends
Description:
Department of Polymer Science and Rubber Technology
Cochin University of Science and Technology
Joshi, K K; Dr.Parameswaran Pillai, P(Cochin University Of Science And Technology, November , 1990)
[+]
[-]
Abstract:
The present work "Nature and Ecological Significance of Nutrient
Regeneration in different Prawn Culture Fields" was undertaken to understand
the seasonal variation of nutrients, nutrient cycling and primary productivity
of the prawn culture systems. The main emphasis was to find the qualitative
and quantitative estimates of distribution of total phosphorus, inorganic
phosphorus, organic phosphorus, total nitrogen and nitrogen fractions in the
water. The effect of nutrient cycling on primary productivity and concentration
of metals also form one part of the study.
The entire thesis comprise of only one major chapter with subchapters
such as, Introduction (I), Review of Literature (2), Material and
Methods (3), Results (14), Discussion (5), Executive Summary (6) and Biblio~
graphy (7)
Description:
Centre of Advanced Studies in Mariculture,Cochin University Of Science And Technology
Radhakrishnan, P; Dr.Sathianandan, K(Cochin University Of Science And Technology, April 30, 1985)
[+]
[-]
Abstract:
Laser-induced damage is the principal limiting
constraint in the design and operation of high-power laser
systems used in fusion and other high-energy laser applications.
Therefore, an understanding of the mechanisms
which cause the radiation damage to the components employed
in building a laser and a knowledge of the damage threshold
of these materials are of great importance in designing a
laser system and to operate it without appreciable degradation
in performance. This thesis, even though covers
three distinct problems for investigations using a dye
Q-switched multimode Nd:glass laser operating at 1062 nm
and emitting 25 ns (FWHM) pulses, lays its main thrust on
damage threshold studies on thin films. Using the same glass
laser two-photon excited fluorescence in rhodamine 6G and
generation and characterisation of a carbon plasma have also
been carried out.
Description:
Department of Physics, Cochin University Of Science And Technology
Radhakrishnan, P; Dr.Sathianandan, K(Cochin University of Science and Technology, April 30, 1985)
[+]
[-]
Abstract:
Laser-induced damage is the principal limiting constraint in the design and operation of high-power laser systems used in fusion and other high-energy laser applications. Therefore, an understanding of the mechanisms which cause the radiation damage to the components employed
in building a laser and a knowledge of the damage threshold of these materials are of great importance in designing a laser system and to operate it without appreciable degradation in performance. This thesis, even though covers three distinct problems for investigations using a dye Q-switched multimode Nd:glass laser operating at 1062 nm and emitting 25 ns (FWHM) pulses, lays its main thrust on damage threshold studies on thin films. Using the same glass
laser two-photon excited fluorescence in rhodamine 6G and generation and characterisation of a carbon plasma have also been carried out. The thesis is presented in seven chapters.
Description:
Department of Physics, Cochin university of Science and Technology
Anantharaman, M R; Sethulakshmi, N; Al-Omari, I A; Suresh, K G(AIP Publishing, March 5, 2014)
[+]
[-]
Abstract:
Nearly half of lanthanum sites in lanthanum manganites were substituted with monovalent
ion-sodium and the compound possessed distorted orthorhombic structure. Ferromagnetic ordering
at 300K and the magnetic isotherms at different temperature ranges were analyzed for estimating
magnetic entropy variation. Magnetic entropy change of 1.5 J kg 1 K 1 was observed near 300 K.
An appreciable magnetocaloric effect was also observed for a wide range of temperatures near
300K for small magnetic field variation. Heat capacity was measured for temperatures lower than
300K and the adiabatic temperature change increases with increase in temperature with a
maximum of 0.62K at 280 K
Mohammed Yusuff, K K; Leeju, P; Arun,V; Manju, Sebastian; Varsha, Gopalakrishnan; Digna, Varghese(Crystallography Journals,Acta Crystallographica Section E ,Structure Reports, July 15, 2009)
[+]
[-]
Abstract:
In the title molecule, C16H11N5, the mean planes of the
quinoxaline and indazole fragments form a dihedral angle of
10.62 (5). In the crystal, weak intermolecular N—H..........N
hydrogen bonds link the molecules into zigzag chains
extending in the [001] direction. The crystal packing also
exhibits pye interactions [centroid–centroid distances of
3.7080 (2) and 3.8220 (5) A ˚ ], which form stacks of the
molecules parallel to the a axis
Archana, R; Dr. R Gopikakumari; Dr. A Unnikrishnan(Cochin University of Science and Technology, March 12, 2015)
[+]
[-]
Abstract:
Modeling of chaotic systems, based on the output time series, is quite
promising since the output often represents the characteristic behaviour of
the total system. It has been an interesting topic for researchers over the past
few years. So far, some methods are developed for the identification of
chaotic systems. Because of the intense complexity of chaotic systems, the
performance of existing algorithms is not always satisfactory. Application of
chaotic system theory to socially relevant problems like environmental
studies is the need of the hour Neural networks have the required self-learning capability to tune the
network parameters (i.e. weights) for identifying highly non-linear and
chaotic systems. In the present work, effectiveness of modeling a chaotic
system using dynamic neural networks has been demonstrated. From the rich
literature available for non-linear modeling with neural networks, the
Recurrent Neural Network (RNN) structure is selected. The Extended
Kalman Filter (EKF) algorithm is used to train the RNN. Further, the
Expectation Maximization algorithm is used to effectively arrive at the initial
states and the state covariance. Particle filter algorithm with its two important
variants namely Sampling Importance Resampling (SIR) and Rao
Blackwellised algorithms are also used for training the given RNN. Four
standard chaotic systems, Lorenz, Rossler, Chua and Chen, are modelled
with the three algorithms. The best algorithm is found to be EKF-EM based
on the least mean square error criterion. Validation of RNN model with EKFEM
algorithm is done in time domain by Estimation of embedding
dimension, Phase plots, Lyapunov Exponents, Kaplan -Yorke dimension and
Bifurcation diagrams. Analysis of the chaotic systems is also performed in
the transform domain using Fourier, Wavelet and Mapped Real Transforms.
viii
Natural chaotic systems are analyzed based on the selected model structure
and training algorithm, taken for analysis. Sunspot, Venice Lagoon and
North Atlantic oscillations are the three of the natural chaotic systems
modelled with the selected RNN model structure and EKF-EM algorithm.
Dakshinamurti,K; Paulose,C S; Siow,Y L(Department of Biotechnology, 1985)
[+]
[-]
Abstract:
Pyridoxal 5'-phosphate (PLP) is the major coenzymatic
form of pyridoxine. There are over one hundred known pyridoxal
5'-phosphate-dependent reactions, most of which are
involved in the metabolism of various amino acids . Pyridoxamine
5'-phosphate can function in aminotransf erase reactions
by the cyclic regeneration of the two active phosphate
forms. Pyridoxal 5'-phosphate-dependent reactions studied
in the nervous system are involved in the catabolism of various
amino acids. The putative neurotransmitters , dopamine,
norepinephrine , serotonin , histamine , aminobutyric acid
and taurine , as well as the sphingoiipids and poly amines are
synthesized by PLP-dependent enzymes. Of these enzymes,
three ( glutamic acid decarboxylase , 5-hydroxytryptophan decarboxylase
and crnithine decarboxylase) seem to have crucial
roles (Fig. '). The clinical effects of pyridoxine deficiency
can be explained on the basis of the known decreases
in the activities of these enzymes