The changes occuring to cashew
kernels during storage at two humidity
levels - 80% to 20% with respect
to organoleptic characteristics,
protein content, carbohydrate content,
oil content, iodine and peroxide
values were studied. From the
present study it is concluded that
organoleptic characteristics of
cashew kernels deteriorates with increase
in humidity. Decrease in protein
and carbohydrate content of
stored cashew kernel is dependent
on humidity. Humidity increased
oxidative rancidification.
Binu, G S; Poulose Jacob, K(International Journal of Computer Science and Network Security, July , 2010)
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Abstract:
In Wireless Sensor Networks (WSN), neglecting the
effects of varying channel quality can lead to an
unnecessary wastage of precious battery resources and in
turn can result in the rapid depletion of sensor energy and
the partitioning of the network. Fairness is a critical issue
when accessing a shared wireless channel and fair
scheduling must be employed to provide the proper flow
of information in a WSN. In this paper, we develop a
channel adaptive MAC protocol with a traffic-aware
dynamic power management algorithm for efficient packet
scheduling and queuing in a sensor network, with time
varying characteristics of the wireless channel also taken
into consideration. The proposed protocol calculates a
combined weight value based on the channel state and link
quality. Then transmission is allowed only for those nodes
with weights greater than a minimum quality threshold
and nodes attempting to access the wireless medium with a
low weight will be allowed to transmit only when their
weight becomes high. This results in many poor quality
nodes being deprived of transmission for a considerable
amount of time. To avoid the buffer overflow and to
achieve fairness for the poor quality nodes, we design a
Load prediction algorithm. We also design a traffic aware
dynamic power management scheme to minimize the
energy consumption by continuously turning off the radio
interface of all the unnecessary nodes that are not included
in the routing path. By Simulation results, we show that
our proposed protocol achieves a higher throughput and
fairness besides reducing the delay.
This paper is a review of the work done on the dynamics of modulated logistic systems.
Three different problems are treated, viz, the modulated logistic map, the parametrically perturbed
logistic map and the combination map obtained by combining two maps of the quadratic family.
Many of the interesting features displayed by these systems are discussed.
Nandakumaran, V M; Bindu M, Krishna; Manu P, John(Cochin University of Science & Technology, 2004)
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Abstract:
Chaotic dynamics of directly modulated semiconductor lasers have been
studied extensively over the last two decades because of their application in secure
optical communication. However, chaos is generally suppressed in such systems when
the nonlinear gain reduction factor is above 0.01 which is very much smaller than
the reported values in semiconductors like InGaAsP. In this paper we show that by
giving an optoelectronic feedback with appropriate delay one can increase the range
of the values of the gain reduction factor for which chaos can be observed. Numerical
studies show that negative feedback is more efficient in producing chaotic dynamics.
Zeena P, Ravi; Dr.Chandramohanakumar, N(Cochin University of Science & Technology, May , 2005)
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Abstract:
Mangrove swamps are unique inter-tidal wetland ecosystems found in sheltered tropical and subtropical shores.Mangrove sediments can be considered as large reservoirs of amino acids,which exist in several different forms,like free amino acids in the sediment micropores,as amino acids,peptides or proteins bound to clay minerals or as amino acids,peptides or proteins bound to humic colloids.Inorder to assess survival conditions of organisms of mangroves,it is important to understand stability of amino acids in the sediments.The amounts of amino acids present in sediment represent a balance between its synthesis and destruction by microorganisms.Thus amino acid analysis offers more insight into the processes of diagenesis,which changes the nature and characteristics of organic matter deposition and decomposition.
Description:
Department of Chemical
Oceanography Cochin University of Science
and Technology
Iron and mixed iron aluminium pillared montrnorillonites prepared by partial hydrolysis method were subjected to room temperature
exchange with transition metals of the first series. The resulting materials were characterised by different spectroscopic techniques
and surface area measurements. About 1-3% transition metals were incorporated into the porous network. The structural
stability of the porous network was not affected by exchange. XRD and AI NMR spectroscopy evidenced the presence of iron
substituted Al13 like polymers in FeAl pillared systems. Acidity and basicity benefited much as a result of metal exchange. Acidity
and basicity were quantified by model reactions, viz., cumene cracking and cyclohexanol decomposition respectively. The presence
of basic sites in otherwise acidic pillared clays, though diminutive in amount can be of much importance in acid base catalysed
reactions.
Manoj,R; Jayaraj,M K(Department of Physics, October , 2006)
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Abstract:
Materials exhibiting transparency and electrical conductivity simultaneously,
transparent conductors, Transparent conducting oxides (TCOs), which have
high transparency through the visible spectrum and high electrical
conductivity are already being used in numerous applications. Low-emission
windows that allow visible light through while reflecting the infrared, this
keeps the heat out in summer, or the heat in, in winter. A thin conducting
layer on or in between the glass panes achieves this. Low-emission windows
use mostly F-doped SnO2. Most of these TCO’s are n type semiconductors
and are utilized in a variety of commercial applications, such as flat-panel
displays, photovoltaic devices, and electrochromic windows, in which they
serve as transparent electrodes. Novel functions may be integrated into the
materials since oxides have a variety of elements and crystal structures,
providing great potential for realizing a diverse range of active functions.
However, the application of TCOs has been restricted to transparent
electrodes, notwithstanding the fact that TCOs are n-type semiconductors.
The primary reason is the lack of p-type TCOs, because many of the active
functions in semiconductors originate from the nature of the pn-junction. In
1997, H. Kawazoe et al.[2] reported CuAlO2 thin films as a first p-type TCO
along with a chemical design concept for the exploration of other p-type
TCOs.
Mridula,S; Sreedevi,Menon K; Mohanan,K; Bijumon,P V(Microwave and Optical Technology Letters, February 20, 2004)
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Abstract:
The radiation characteristics of a microstrip-line-excited rectangular dielectric resonator antenna (DRA) are studied experimentally.The radiation charactristics and excitation of different modes are highly influenced by the orientation of the DR,feed line parameters ,and finite size of the ground plane
Padmaja, G; Ravi Kumar, A V; Vidyalal, V; Radhakrishnan, P; Nampoori, V P N; Vallabhan, C P G(Springer, June , 1991)
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Abstract:
The spectroscopic analysis of the emission from the plasma produced by irradiating a highT c superconducting GdBa2Cu3O7 target with a high power Nd:YAG laser beam shows the existence of the bands from different oxides in addition to the lines from neutrals and ions of the constituent elements. The spectral emissions by oxide species in laser-induced plasma show considerable time delays as compared to those from neutral and ionic species. Recombination processes taking place during the cooling of the hot plasma, rather than the plasma expansion velocities, have been found to be responsible for the observed time delays in this case. The decays of emission intensities from various species are found to be non-exponential.
Biju, John; Rajendran, C P(Cochin University of Science and Technology, 2003)
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Abstract:
The purpose of the present study is to understand the surface deformation associated with the Killari and Wadakkancheri earthquake and to examine if there are any evidence of occurrence of paleo-earthquakes in this region or its vicinity. The present study is an attempt to characterize active tectonic structures from two areas within penisular India: the sites of 1993 Killari (Latur) (Mb 6.3) and 1994 Wadakkancheri (M 4.3) earthquakes in the Precambrian shield. The main objectives of the study are to isolate structures related to active tectonism, constraint the style of near – surface deformation and identify previous events by interpreting the deformational features. The study indicates the existence of a NW-SE trending pre-existing fault, passing through the epicentral area of the 1993 Killari earthquake. It presents the salient features obtained during the field investigations in and around the rupture zone. Details of mapping of the scrap, trenching, and shallow drilling are discussed here. It presents the geologic and tectonic settings of the Wadakkancheri area and the local seismicity; interpretation of remote sensing data and a detailed geomorphic analysis. Quantitative geomorphic analysis around the epicenter of the Wadakkancheri earthquake indicates suitable neotectonic rejuvenation. Evaluation of remote sensing data shows distinct linear features including the presence of potentially active WNW-ESE trending fault within the Precambrian shear zone. The study concludes that the earthquakes in the shield area are mostly associated with discrete faults that are developed in association with the preexisting shear zones or structurally weak zones
Eswaran Namboodiri, K K; Sukumaran Nair, M K (Department of Applied Economics)(Department of Applied Economics, Faculty of Social Science, July , 1997)
Reji, Philip; Sathy, P; Nampoori, V P N; Jacob, Philip; Vallabhan, C P G(IOP, 1992)
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Abstract:
Two-photon absorption in methanol solutions of Rhodamine 6G is investigated by photoacoustics using the second harmonic of a pulsed Nd:YAG laser. Competition between one-photon and two-photon processes is observed, depending critically on the sample concentration and input light flux.
Madhu, V; Mohankumar, K(Cochin University of Science and Technology, October , 2004)
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Abstract:
The present work is an attempt to understand the characteristics of the upper troposphere and lower stratosphere over the Asian summer monsoon region, more specifically over the Indian subcontinent. Mainly three important parameters are taken such as zonal wind, temperature and ozone over the UT/LS of the Asian summer monsoon region. It made a detailed study of its interannual variability and characteristics of theses parameters during the Indian summer monsoon period. Monthly values of zonal wind and temperature from the NCEP/NCAR reanalysis for the period 1960-2002 are used for the present study. Also the daily overpass total ozone data for the 12 Indian stations (from low latitude to high latitudes) from the TOMS Nimbus 7 satellite for the period 1979 to 1992 were also used to understand the total ozone variation over the Indian region.
The study reveals that if QBO phases in the stratosphere is easterly or weak westerly then the respective monsoon is found to be DRY or below Normal . On the other hand, if the phase is westerly or weak easterly the respective Indian summer monsoon is noted as a WET year. This connection of stratospheric QBO phases and Indian summer monsoon gives more insight in to the long-term predictions of Indian summer monsoon rainfall. Wavelet analysis and EOF methods are the two advanced statistical techniques used in the present study to explore more information of the zonal wind that from the smaller scale to higher scale variability over the Asian summer monsoon region. The interannual variability of temperature for different stratospheric and tropospheric levels over the Asian summer monsoon region have been studied. An attempt has been made to understand the total ozone characteristics and its interannual variablilty over 12 Indian stations spread from south latitudes to north latitudes. Finally it found that the upper troposphere and lower stratosphere contribute significantly to monsoon variability and climate changes. It is also observed that there exists a link between the stratospheric QBO and Indian summer monsoon
Mohammed Yusuff, K K; Sridevi, N; Pearly Sebastian, C(Wiley InterScience, January 9, 2007)
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Abstract:
Ruthenium(III) complexes of the Schiff bases
formed by the condensation of polymer bound aldehyde and
the amines, such as 1,2-phenylenediamine (PS-opd), 2-aminophenol
(PS-ap), and 2-aminobenzimidazole (PS-ab) have been
prepared. The magnetic moment, EPR and electronic spectra
suggest an octahedral structure for the complexes. The complexes
of PS-opd, PS-ap, and PS-ab have been assigned the
formula [PS-opdRuCl3(H2O)], [PS-apRuCl2(H2O)2], [PS-ab-
RuCl3(H2O)2], respectively. These complexes catalyze oxidation
of catechol using H2O2 selectively to o-benzoquinone. The catalytic activity of the complexes is in the order [PS-ab-
RuCl3(H2O)2] . [PS-opdRuCl3(H2O)] [PS-apRuCl2(H2O)2].
Mechanism of the catalytic oxidation of catechol by ruthenium(
III) complex is suggested to take place through the formation
of a ruthenium(II) complex and its subsequent oxidation
by H2O2 to the ruthenium(III) complex.
Dann, V J; Dr. Nampoori, V P N; Dr. Nandakumaran, V M(Cochin University of Science & Technology, October , 2008)
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Abstract:
Laser induced plasma (LIP) emissions from some metal oxide targets were
studied with corresponding metal targets of pure quality as a reference. Atomic emissions
in the visible region were used in the spectroscopic procedures of LIP characterization.
The studies were meant to throw light into LIP dynamics and they provided many
experimental results which improved the general awareness of plasma state.When target materials were photo-ablated with an energetically suitable laser
pulse, they developed electric charges in them.An electrical signal which was delivered
from the target served as an alternative probe signal for the diagnostics of LIP and to
track different charged states in the plasma. The signal showed a double peak distribution
with positive polarity and a modified time of flight with various voltage levels of a given
polarity.The expansion dynamics of LIP in magnetic field were also investigated
by monitoring the voltage transients generated at the target.
Description:
International School of Photonics,
Cochin University of Science and Technology
Saju, K K; Dr Sreejith, P S(Cochin University of Science & Technology, July , 2009)
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Abstract:
This thesis summarizes the results on the growth and characterisation of
thin films of HA grown on TiAl6V4 (Ti) implant material at a lower
substrate temperature by a combination of Pulsed laser deposition and a
hydrothermal treatment to get sufficiently strong crystalline films
suitable for orthopaedic applications. The comparison of the properties
of the coated substrate has been made with other surface modification
techniques like anodization and chemical etching. The in-vitro study has
been conducted on the surface modified implants to assess its cell
viability. A molecular level study has been conducted to analyze the
adhesion mechanism of protein adhesion molecules on to HA coated
implants.
Description:
Division of Mechanical Engineering,
School of Engineering,
Cochin University of Science and Technology