Heterotrophic bacterial flora of Pmonadon from an apparently healthy hatchery system as well as a pool with heavy mortality were isolated and studied. In the
healthy systems comparatively higher generic diversity with Pseudomonas, Acinetobacter, Bacillus, Micrococcus, members of the family Enterobacteriaceae
and coryneform group in the diminishing order of dominance was recorded. Meanwhile from the moribund larvae and rearing water Aeromonas and Pseudomonas
could be isolated in almost equal proportions. Strikingly, Aeromonas could not be isolated from the apparently healthy larval rearing system and its exclusive
occurrence in the sick culture system in comparatively higher percentage suggested its possible role in the mortality. They were found to be highly halophilic
exhibiting growth at 10% NaCl. On testing their sensitivity to twenty antibiotics, four of them (Streptomycin, Gentamycin, Methamine mandelate and
Cloramphenicol) were found to be effective on all the isolates of Aeromonas and Pseudomonas suggesting their possible application in the hatchery system in
times of emergency. While doing so, Streptomycin would do comparatively better than the others as the minimum inhibitory dose required was comparatively
lower (200ppm) within a period of 24 hours
Neil, Scholastin Correya; Dr.Rosamma,Philip(Cochin University of Science And Technology, October , 2012)
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Abstract:
The marine environment is indubitably the largest contiguous habitat on
Earth. Because of its vast volume and area, the influence of the world ocean on
global climate is profound and plays an important role in human welfare and
destiny. The marine environment encompasses several habitats, from the sea
surface layer down through the bulk water column, which extends >10,000 meters
depth, and further down to the habitats on and under the sea floor. Compared to
surface habitats, which have relatively high kinetic energy, deep-ocean circulation
is very sluggish. By comparison, life in the deep sea is characterized by a relatively
constant physical and chemical environment. Deep water occupying the world
ocean basin is a potential natural resource based on its properties such as low
temperature, high pressure and relatively unexplored properties. So, a judicious
assessment of the marine resources and its management are essential to ensure
sustainable development of the country’s ocean resources.
Marine sediments are complex environments that are affected by both
physiological and biological factors, water movements and burrowing animals.
They encompass a large extent of aggregates falling from the surface waters. In
aquatic ecosystems, the flux of organic matter to the bottom sediments depend on
primary productivity at the ocean surface and water depth. Over 50% of the earth’s
surface is covered by deep-sea sediments that are primarily formed through the
continual deposition of particles from the productive pelagic waters (Vetriani et al.,
1999). These aggregates are regarded as ‘hot spots’ of microbial activity in the
ocean (Simon et al., 2002). This represents a good nutritional substrate for
heterotrophic bacteria and favours bacterial growth
Description:
School of Marine Sciences, Cochin University of Science And Technology
Santhi, Thirumani S; Dr.Chandrika, V(Cochin University of Science And Technology, June , 1992)
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Abstract:
The principal interest of the present investigation was to determine
seasonal and vertical variation of chemoorganotrophic utilisation of glucose
and sodium—acetate by the natural bacterial population in the aquaculture
pond of Narakkal, Cochin using techniques which allow maintenance of
the in situ gaseous concentrations during incubation. In addition salinity,
dissolved oxygen, temperature, hydrogen—ion—.concentration, primary production,
plant pigments and total bacterial concentration were determined
seasonally and vertically because of their possible relationship to chemoorganotrophy.
Hamsakutty, V; Dr.Mathew, K T(Cochin University of Science and Technology, March , 2007)
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Abstract:
In this thesis, the author proposes a new geometry DR antenna-the Hexagonal Dielectric Resonator Antenna(HDRA)-capable of multiple frequency operation on a single feed of excitation.This avoids the conventional use of miniaturizes the structure.The properties of the HDRA on microstrip as well as coaxial feeding have been studied.The analysis of radiation characteristics indicates a gain comparable with other shapes.The antenna is capable of providing efficiency around 98%.The simulation using HFSS also yields results in conformity with the experimental results.Mode analysis is carried out and the modes are identified.The determination of the reflection characteristics through theoretical analysis using FDTD validates the multifrequency operation of the antenna,The antenna finds application in DCT,PCS and WLAN bands.
Description:
Department of
Electronics, Cochin University of Science and Technology
The 21st century is marked by a paradigm shift in education that has resulted both
in threats and opportunities. It has brought new challenges and an opportunity for
higher education. Higher education in India is undergoing rapid changes. The
challenges ahead are multifaceted and multidimensional. Though the data show a
massive growth in the number of students' enrollment in colleges/universities, holistic
view reveals that still only a meager of the total population has access to higher
education. Globalization and privatization are imposing new challenges but the
nations are still entangled in solving the basic problems of accessibility to higher
education for all. In the wake of the transition from elitist to mass education,
universities worldwide are under pressure to enhance access and equity, on the one
hand, and to maintain high standards of quality and excellence, on the other. Today
the notion of equity not only implies greater access to higher education, but also
opportunities for progress. In recent debates on higher education, the notions of equity
and access go beyond minority to diversity. Affirmative action, too, has become raceexclusive
and gender-neutral.1
Description:
Journal of Global Economy,
Volume 6 No 4, JULY-AUGUST, 2010
Vimalkumar, T V; Dr.Vijayakumar, K P(Cochin University of Science & Technology, August , 2011)
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Abstract:
In the present work we report the preparation details studies on ZnO thin films. ZnO
thin films are prepared using cost effective deposition technique viz., Chemical Spray
Pyrolysis (CSP). The method is very effective for large area preparation of the ZnO thin
film. A new post-deposition process could also be developed to avoid the adsorption of
oxygen that usually occurs after the spraying process i.e., while cooling. Studies were done
by changing the various deposition parameters for optimizing the properties of ZnO thin
film. Moreover, different methods of doping using various elements are also tried to
enhance the conductivity and transparency of the film to make these suitable for various
optoelectronic applications.
Description:
Department of Physics,
Cochin University of Science and Technology
Poulose Jacob,K; Sreela Sasi; Rekha, James K(IEEE, December 9, 2009)
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Abstract:
Decimal multiplication is an integral part of
financial, commercial, and internet-based computations.
This paper presents a novel double digit decimal
multiplication (DDDM) technique that offers low latency
and high throughput. This design performs two digit
multiplications simultaneously in one clock cycle. Double
digit fixed point decimal multipliers for 7digit, 16 digit and
34 digit are simulated using Leonardo Spectrum from
Mentor Graphics Corporation using ASIC Library. The
paper also presents area and delay comparisons for these
fixed point multipliers on Xilinx, Altera, Actel and Quick
logic FPGAs. This multiplier design can be extended to
support decimal floating point multiplication for IEEE 754-
2008 standard.
Description:
Nature & Biologically Inspired Computing, 2009. NaBIC 2009. World Congress on
A new group of compounds with composition (Ba5-xSrx) Nb4015, having high
permittivity and low loss have been prepared and characterized in the microwave
frequency region . X-ray diffraction studies showed that monophase compound
existed for all values of x from 0 to 5. Microwave dielectric properties such as
and c f showed smooth variation with x , while the unloaded quality factor (Qu)
showed remarkable improvement with x
Thomas, Baby; Sathianandan, K; Nampoori, V P N; Vallabhan, C P G; Ramachandran, T(American Institute of Physics, September , 1991)
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Abstract:
A high power Nz laser of the double-Blumlein type having a modified gas flow system,
electrode configuration, and discharge geometry with minimum inductance is described. By
incorporating a triggere’d-pressurized spark gap switch, arc-free operation was achieved
for a wide E/P range. The device gives a peak power in excess of 700 kW with a FWHM of
3 ns and an efficiency of 0.51%, which is remarkably high for a pulsed nitrogen laser
system. The dependence of output power on parameters such as operating pressure, voltage,
and repetition rate are discussed.
Sasi Kumar, P R; Harilal, S S; Nampoori, V P N; Vallabhan, C P G(Pramana, March , 1994)
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Abstract:
High resolution optogalvanic spectrum of the (11, 7) band in the first positive system
of nitrogen molecule has been recorded from 17179 to 17376 cm- 1. Assignment of 432 rotational
lines belonging to the 27 branches of this band has been carried out.
Sasi Kumar, P R; Ambadi, B; Nampoori, V P N; Vallabhan, C P G(Springer, February , 1993)
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Abstract:
Doppler limited high resolution spectrum in the wavelength region 17224 to 17236 cm−1 of the first positive system (B 3Π g −A 3Σ u + ) of the N2 molecule is recorded by optogalvanic spectroscopic technique using a single mode ring dye laser. It is observed that the intensity and line width of the rotational line increase with the discharge current. Dependence of the collision broadening coefficient on the current was also evaluated.
The paper presents a compact planar Ultra Wide Band ¯lter employing folded stepped
impedance resonators with series capacitors and dumb bell shaped defected ground structures. An
interdigital quarter wavelength coupled line is used for achieving the band pass characteristics. The
transmission zeros are produced by stepped impedance resonators. The ¯lter has steep roll o® rate and
good attenuation in its lower and upper stop bands, contributed by the series capacitor and defected
ground structures respectively.
Description:
Progress In Electromagnetics Research C, Vol. 49, 123{131, 2014
Thomas, Kurian; Jacob, Samuel; Thommachan, Xavier(Wiley Periodicals, December , 2001)
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Abstract:
High styrene rubber ionomers were prepared by sulfonating styrene–butadiene
rubber of high styrene content (high styrene rubber) in 1,2-dichloroethane using
acetyl sulfate reagent, followed by neutralization of the precursor acids using methanolic
zinc acetate. The ionomers were characterized using X-ray fluorescence spectroscopy,
Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance
spectroscopy (NMR), dynamic mechanical analysis (DMA), and also by the evaluation
of mechanical properties. The FTIR studies of the ionomer reveal that the sulfonate
groups are attached to the benzene ring. The NMR spectra give credence to this
observation. Results of DMA show an ionic transition (Ti) in addition to glass–rubber
transition (Tg). Incorporation of ionic groups results in improved mechanical properties
as well as retention of properties after three cycles of processing
Description:
Journal of Applied Polymer Science, Vol. 85, 2294–2300 (2002)
Subhadra, V K; Syamaprasad, U; Vallabhan, C P G(American Institute of Physics, 1983)
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Abstract:
Results of axiswise measurements of the electrical conductivity (dc and ac) and dielectric constant of NH4H2PO4 confirm the occurrence of the recently suggested high‐temperature phase transition in this crystal (at 133 °C). The corresponding transition in ND4D2PO4 observed here for the first time takes place at 141.5 °C. The mechanism involved in these transitions and those associated with the electrical conduction and dielectric anomalies are explained on the basis of the motional effects of the ammonium ions in these crystals. Conductivity values for deuterated crystals give direct evidence for the predominance of protonic conduction throughout the entire range of temperatures studied (30–260 °C).