Nithyaja, B; Jisha, V K; Tintu, R; Saramma, A V; Nampoori, V P N(Laser Physics, 2009)
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Abstract:
The growth kinetics of an aerial bacterial colony on solid agar media was studied using laser
induced fluorescence technique. Fluorescence quenching of Rhodamin B by the bacterial colony was utilized
for the study. The lag phase, log phase, and stationary phase of growth curve of bacterial colony was identified
by measuring peak fluorescence intensity of dye doped bacterial colony.
Seema,P V; Sudha, B; Pius S,Padayatti; Asha,Abraham; Raghu,K G; Paulose,C S(Department of Biotecnology, June , 1996)
[+]
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Abstract:
The functional basis of diabetes-mellitus to a certain extent,
can be elucidated by studying diabetes-induced changes
in metabolic enzymes. Malate dehydrogenase (MDH),
is an enzyme directly involved in glucose metabolism. The
kinetic parameters of MDH and its purified cytosolic isozyme,
S-MDH, have been studied in the liver of streptozotocin-
diabetic rats; also the potential of the leaf extract of A.
marmelose as an was investigated. The
Km of the liver enzyme increased significantly, in both
crude and purified preparations in the diabetic state when
compared to Lhe respective controls. Insulin as well as leaf-
•extract treatment of the diabetic rats brought about a reversal
of K. values to near normal. Vmax of purified S-MDH
was significantly higher in the diabetic state when compared
to the control. Insulin and leaf extract treatment did not
reverse this change. Since MDH is an important enzyme in
glucose metabolism, the variation in its quantitative and
qualitative nature may contribute to the pathological status
of diabetes. The fact that leaf extract of A. marmelose
was found to be as effective as insulin in restoration of blood
glucose and body weight to normal levels, the use of A.
marmelose as potential hypoglycemic agent is suggested.
On-line handwriting recognition has been a frontier
area of research for the last few decades under the purview of
pattern recognition. Word processing turns to be a vexing
experience even if it is with the assistance of an alphanumeric
keyboard in Indian languages. A natural solution for this
problem is offered through online character recognition. There is
abundant literature on the handwriting recognition of western,
Chinese and Japanese scripts, but there are very few related to
the recognition of Indic script such as Malayalam. This paper
presents an efficient Online Handwritten character Recognition
System for Malayalam Characters (OHR-M) using K-NN
algorithm. It would help in recognizing Malayalam text entered
using pen-like devices. A novel feature extraction method, a
combination of time domain features and dynamic representation
of writing direction along with its curvature is used for
recognizing Malayalam characters. This writer independent
system gives an excellent accuracy of 98.125% with recognition
time of 15-30 milliseconds
Description:
2010 First International Conference on Integrated Intelligent Computing
Sheeja, N K(Emerald Group Publishing Limited, August 15, 2012)
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Abstract:
This paper aims to describe recent developments in the services provided by Indian
electronic thesis and dissertation (ETD) repositories. It seeks to explore the prospect of knowledge
formation and diffusion in India and to discuss the potential of open access e-theses repositories for
knowledge management.This study is based on literature review and content analysis of
IndianETDrepository websites. Institutional repositories and electronic thesis and dissertation projects
in India were identified through a literature survey as well as internet searching and browsing.
The study examines the tools, type of contents, coverage and aims of Indian ETD repositories.The paper acknowledges the need for knowledge management for national development.
It highlights the significance of an integrated platform for preserving, searching and retrieving Indian
theses. It describes the features and functions of Indian ETD repositories.The paper provides insights into the characteristics of the national repository of
ETDs of India, which encourage and support open access to publicly-funded research
Archana, S N; Padmakumar, P K; Beena, C(INFLIBNET Centre, Ahmedabad, March , 2013)
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Abstract:
In this knowledge era, the value of corporations, academic organizations and individuals is directly
related to their knowledge and intellectual capital(IC). A newand potentially paradigm shift focus
in the intersection between knowledge and intelligence is the recognition of the importance of
understanding the intellectual capital of organizations. This paper explains how Cochin University
of Science and Technology (CUSAT) is identifying and managing its intellectual capital for creating
competitive advantage for the future. This paper also explores the different cost effective knowledge
management strategies applied at CUSAT for managing its intellectual capital
Description:
9th International CALIBER - 2013, INFLIBNET Centre, Gandhinagar, Gujarat, March 21-23, 2013
Anantharaman, M R; Lija, Joy K; Sooraj, V; Swapna, Nair S; Narayanan, T N; Ajayan, P M; Sethulakshmi, N(AIP Publishing, March 28, 2014)
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Abstract:
Commercial samples of Magnetite with size ranging from 25–30nm were coated with polyaniline by
using radio frequency plasma polymerization to achieve a core shell structure of magnetic nanoparticle
(core)–Polyaniline (shell). High resolution transmission electron microscopy images confirm the core
shell architecture of polyaniline coated iron oxide. The dielectric properties of the material were
studied before and after plasma treatment. The polymer coated magnetite particles exhibited a large
dielectric permittivity with respect to uncoated samples. The dielectric behavior was modeled using a
Maxwell–Wagner capacitor model. A plausible mechanism for the enhancement of dielectric
permittivity is proposed
Girijavallabhan, C P; Radhakrishnan, P; Nampoori, V P N; Geetha, K; Rajesh, M(Journal of Optics A: Pure and Applied Optics, Institute of Physics Publishing, January 13, 2006)
[+]
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Abstract:
We present a compact solid-state laser based on leaky mode propagation
from a dye-doped polymer free-standing film waveguide. The edge emitted
spectrum clearly indicated the existence of periodic resonant modes. The
reflections from the lateral faces of the free-standing film provided the
optical feedback thus giving rise to a Fabry–Perot like optical cavity. This
together with the guidance through the gain medium gave rise to intense
narrow emission lines. For a pump energy of 1.82 mJ/pulse, an intense line
with FWHM ∼0.4 nmwas observed at 576.5 nm.
Radhakrishnan, P; Nampoori, V P N; Girijavallabhan, C P; Geetha, K; Rajesh, M(Journal of Optics A: Pure and Applied Optics, Institute of Physics Publishing, January 13, 2006)
[+]
[-]
Abstract:
We present a compact solid-state laser based on leaky mode propagation
from a dye-doped polymer free-standing film waveguide. The edge emitted
spectrum clearly indicated the existence of periodic resonant modes. The
reflections from the lateral faces of the free-standing film provided the
optical feedback thus giving rise to a Fabry–Perot like optical cavity. This
together with the guidance through the gain medium gave rise to intense
narrow emission lines. For a pump energy of 1.82 mJ/pulse, an intense line
with FWHM ∼0.4 nmwas observed at 576.5 nm.
Nampoori, V P N; Radhakrishnan, P; Girijavallabhan, C P; Geetha, K; Rajesh, M(Journal of Optics A: Pure and Applied Optics, Institute of Physics Publishing, January 13, 2006)
[+]
[-]
Abstract:
We present a compact solid-state laser based on leaky mode propagation
from a dye-doped polymer free-standing film waveguide. The edge emitted
spectrum clearly indicated the existence of periodic resonant modes. The
reflections from the lateral faces of the free-standing film provided the
optical feedback thus giving rise to a Fabry–Perot like optical cavity. This
together with the guidance through the gain medium gave rise to intense
narrow emission lines. For a pump energy of 1.82 mJ/pulse, an intense line
with FWHM ∼0.4 nmwas observed at 576.5 nm.
Santhi Ani, Joseph; Gaurav, Sharma; Misha, Hari; Mathew, S; Radhakrishnan, P; Nampoori, V P N(Optical Society of America, 2010)
[+]
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Abstract:
We demonstrate the possibility of realizing, all-optical switching in gold nanosol. Two overlapping laser beams are used for this purpose, due to which a low-power beam passing collinear to a high-power beam will undergo cross phase modulation and thereby distort the spatial profile. This is taken to advantage for performing logic operations. We have also measured the threshold pump power to obtain a NOT gate and the minimum response time of the device. Contrary to the general notion that the response time of thermal effects used in this application is of the order of milliseconds, we prove that short pump pulses can result in fast switching. Different combinations of beam splitters and combiners will lead to the formation of other logic functions too.
Optical fiber based laser induced fluorescence (LIF)
measurements were carried out using Rhodamine B to analyze
two different species of bacteria , a Gram-positive bacteria
namely Bacillus smithii , and fibrin alginolvticus, a Gram-
negative bacteria . The fiber sensor was clearly able to distinguish
between the two species of bacteria . Quenching effect of the dye
Rhodamine B by Bacillus smithii was observed . The effect of dye
on the samples was also studied in detail.
Nampoori, V P N(Wiley Inter Science, March 27, 2007)
[+]
[-]
Abstract:
Optical fiber based laser induced fluorescence (LIF)
measurements were carried out using Rhodamine B to analyze
two different species of bacteria , a Gram-positive bacteria
namely Bacillus .cmithii , and fibrin alginolvticus, a Gram-'
negative bacteria . The fiber sensor was clearly able to distinguish
between the two species of bacteria . Quenching effect of the dye
Rhodamine B by Bacillus smitltii was observed . The effect of dye
on the samples was also studied in detail.
Reethamma, Thomas; Nampoori, V P N(Elsevier, 1990)
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Abstract:
Fluorescence of BaS: Sm phosphor has been studied using a pulsed Nitrogen laser (337.1 nm) as the excitation source. The spectrum consists of a broad band in the region 540–660nm superposed by the characteristic Sm3+ lines. Energy level splitting pattern of Sm3+ due to crystal field effects has been calculated and relevent field parameters are evaluated. Analysis shows that Sm3+ takes up Ba2+ substitutional sites.
Nibu, A George; Vallabhan, C P G; Nampoori, V P N; George, A K; Radhakrishnan, P(Taylor & Francis, 2001)
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Abstract:
In this paper we report the use of a laser induced phoroacoustic technique for the detection of multiple phase transitions in heptyl-oxy-cyanobiphenyl (70CB) and octyl-oxy-cyanobiphenyl (80CB) liquid crystals. The observed photoacoustic signal amplitude profile carries clear signatures of two tirst order transitions in 70CB and two tirst order and a second order transitions in 80CB. Analysis of the experimental data using Rosencwaig-Gersho theory shows that the sudden decrease in the photoacoustic (PA) signal amplitude during phase transitions is due to a sharp increase in the heat capacity of the samples near the transition temperatures.
Jacob, Philip; Manivannan, S; Dhanuskodi, S; Tiwari, S K(Springer, 2008)
[+]
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Abstract:
N-alkyl-2,6-dimethyl-4(1H)-pyridinones, salts of
4-dimethylaminopyridine and 2-amino-5-nitropyridine are considered
to be potential candidates for nonlinear optical (NLO)
applications, in particular for the generation of blue-green laser
radiation. Single crystals were grown following the slow evaporation
technique at constant temperature. Single-shot laserinduced
surface damage thresholds in the range 3–10 GW/cm2
were measured using a 18 ns Q-switched Nd:YAG laser. The
surface morphologies of the damaged crystals were examined
under an optical microscope and the nature of damage identified.
The Vicker’s microhardness was determined at a load of
98.07 mN. The thermal transport properties, thermal diffusivity
(α), thermal effusivity (e), thermal conductivity (K) and heat
capacity (Cp), of the grown crystals were measured by an improved
photopyroelectric technique at room temperature. All
the results are presented and discussed.
Girijavallabhan, C P; Radhakrishnan, P; Nampoori, V P N; Sajan, D George; Aji, A Anapara; K G K Warrier(Proceedings of SPIE, 2003)
[+]
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Abstract:
In this paper, we report the measurements of thermal diffusivity of nano Ag metal dispersed ceramic alumina
matrix sintered at different temperatures using laser induced non-destructive photoacoustic technique. Measurements of
thermal diffusivity also have been carried out on specimens with various concentration of nano metal. Analysis of the
data is done on the basis of one-dimensional model of Rosencwaig and Gersho. The present measurements on the
thermal diffusivity of nano metal dispersed ceramic alumina shows that porosity has a great influence on the heat
transport and the thermal diffusivity value. The present analysis also shows that the inclusion of nano metal into
ceramic matrix increases its interconnectivity and hence the thermal diffusivity value. The present study on the samples
sintered at different temperature shows that the porosity of the ceramics varies considerably with the change in sintering
temperature. The results are interpreted in terms of phonon assisted heat transfer mechanism and the exclusion of pores
with the increase in sintering temperature.
Radhakrishnan, P; Nampoori, V P N; Girijavallabhan, C P; Sajan, D George; Aji, A Anapara; K G K Warrier(Proceedings of SPIE, 2003)
[+]
[-]
Abstract:
In this paper, we report the measurements of thermal diffusivity of nano Ag metal dispersed ceramic alumina
matrix sintered at different temperatures using laser induced non-destructive photoacoustic technique. Measurements of
thermal diffusivity also have been carried out on specimens with various concentration of nano metal. Analysis of the
data is done on the basis of one-dimensional model of Rosencwaig and Gersho. The present measurements on the
thermal diffusivity of nano metal dispersed ceramic alumina shows that porosity has a great influence on the heat
transport and the thermal diffusivity value. The present analysis also shows that the inclusion of nano metal into
ceramic matrix increases its interconnectivity and hence the thermal diffusivity value. The present study on the samples
sintered at different temperature shows that the porosity of the ceramics varies considerably with the change in sintering
temperature. The results are interpreted in terms of phonon assisted heat transfer mechanism and the exclusion of pores
with the increase in sintering temperature
Nampoori, V P N; Radhakrishnan, P; Girijavallabhan, C P; Sajan, D George; Aji, A Anapara; K G K Warrier(Proceedings of SPIE, 2003)
[+]
[-]
Abstract:
In this paper, we report the measurements of thermal diffusivity of nano Ag metal dispersed ceramic alumina
matrix sintered at different temperatures using laser induced non-destructive photoacoustic technique. Measurements of
thermal diffusivity also have been carried out on specimens with various concentration of nano metal. Analysis of the
data is done on the basis of one-dimensional model of Rosencwaig and Gersho. The present measurements on the
thermal diffusivity of nano metal dispersed ceramic alumina shows that porosity has a great influence on the heat
transport and the thermal diffusivity value. The present analysis also shows that the inclusion of nano metal into
ceramic matrix increases its interconnectivity and hence the thermal diffusivity value. The present study on the samples
sintered at different temperature shows that the porosity of the ceramics varies considerably with the change in sintering
temperature. The results are interpreted in terms of phonon assisted heat transfer mechanism and the exclusion of pores
with the increase in sintering temperature
Bindhu, C V; Harilal, S S; Riju, C Issac; Geetha K, Varier; Nampoori, V P N; Vallabhan, C P G(World Scientific Publishing Company, 1995)
[+]
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Abstract:
Measurement of thermal lensing signal as a function of laser power made in Rhodamine B solutions in methanol give clear evidence of two photon absorption process within certain concentration ranges when 488 nm Ar+ laser beam is used as the pump source. Only one photon process is found to occur when 514 nm and 476 nm beams are used as the pump.
A novel method of blending natural rubber with polyvinylchloride in the latex
stage was developed, Dioctyl phthalate (DOP) and Amine terminated natural rubber
(ATNR) were used as plasticisers, for improving the mechanical properties of
these blends. Properties of the latex stage blends were compared with those of
dry blends. Latex stage blends showed superior mechanical properties compared
to the blends prepared in the dry state. The ageing resistance, oil resistance and
processability were found to be improved by latex stage blending.