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.
Joselet Mathew; Dr.Kulasekarapandian, S(Cochin University Of Science And Technology, November 6, 1990)
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Abstract:
This thesis deals with the population characteristics of Artemia
and the effect of different environmental parameters on the different
stages of Artemia in a salina at Tuticorin, south east coast of India.
The present investigation was carried out from 1985 to I987.
The study was initiated by undertaking a survey to find out suitable
Artemia habitats along the south east coast of India and a perennial
salina with an area of 0.25 ha was selected at Karapad (Tuticorin). Weekly
samplings were made for two full calender years (1986-87) to collect
the different stages of Artemia population as well as the different
environmental parameters. The thesis comprises of the following sections: Introduction, materials and methods, systematics, biology and distribution of Artemia, results and discussion, summary and bibliography. The section on results
and discussion gives the characteristics of Artemia population in the
salina, the seasonal variations of different environmental parameters
in the salina and their effects on different stages of Artemia population.
Description of an experiment conducted to show the sudden changes of
salinity on different stages of Artemia is also given as a separate
section.
Description:
Centre Of Advanced Studies In Mariculture,Cochin University Of Science And Technology
Manju, Sebastine; Pillai, N G K(Cochin University Of Science And Technology, October 23, 2014)
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Abstract:
Globally most of the conventional fish stocks have reached a state of optimum exploitation or even over-exploitation; efficient utilization of non-conventional resources is necessary to meet the supply-demand gap for protein supply. Mesopelagic fishes can be considered as one such promising resource for the future, if appropriate harvest and post-harvest technologies are developed. Increasing human population and increasing demand for cheaper food fishes has made myctophids a possible potential resource for future exploitation and utilization. Earlier studies indicated the abundance of Diaphus spp. in the eastern and northeastern Arabian Sea. The present study also indicates the dominance of Diaphus spp. in the deep sea trawling grounds of south west coast of India. Commercial viability of the myctophid fishing in the Indian waters has to be worked out. The present catch estimation is based on the Stratified Random Sampling Method from the landing data. As the coverage of sampling area was limited and the gear efficiency was not standardized, the data generated are not precise. A counter check for the estimates is also not possible due to the absence of comparable works in the study area. Fish biomass estimation by acoustics survey coupled with direct fishing would only confirm the accuracy of estimates. Exploratory surveys for new fishing areas to be continued, for gathering the distribution, abundance, biological and ecological data and map the potential fishing ground on a GIS platform and the data should be provided to the commercial entrepreneurs. Generally non-conventional and non-targeted resources are under low fishing pressure and exploitation rates. Low values of fishing mortality and exploitation rates indicate that removal from the stock by fishing was only nominal from the present fishing grounds. The results indicate that the stock is almost at virgin state and remains grossly underexploited. Since the extent of distribution and abundance of the stock in the ecosystem remains to be ascertained, sustainable yield could not be estimated. Also the impact of myctophids harvest, on other commercially important fishes, has to be studied.
Harikrishnan, M; Dr.Madhusoodana,Kurup B(Cochin University Of Science And Technology, September , 1997)
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Abstract:
Macrobrachium rosenbergii (de Man) and M.ide77a
(Hilgendorf) form two commercially important Palaemonid
prawns of the Vembanad lake (9 28' and 10 10’ N and 76
13' and 76 31' E). Both of them were known to have
contributed to a very lucrative fishery during the sixties,
however, in recent years these natural resources have badly
depleted owing to the impact of many man made alterations
brought about in the ecosystem such as habitat reduction,
physical obstruction imposed in the migratory pathway of
these species, pollution hazards, etc,. Changed
environmental conditions and increased fishing pressures
caused persistent alterations in the stock size of these
prawns during the past so many years, however, no serious
attempt was made to monitor the stock size from time to time
and also to bring out the resource characteristics. Though,
the morphotypic differentiation in grow out male population
of M.rosenbergii has been documented, no similar studies
were conducted with regard to natural male and female
population. Based on the data collected during fishery
cruise surveys conducted in Vembanad lake from March '94 to
February '96, population characteristics. postlarval
distribution, fishery and population dynamics of
M.rosenbergii and M.ide77a of the lake were studied in
detail.
Description:
School of
Industrial Fisheries, Cochin University of Science and Technology
Abdussamad, E M; Dr.Gopinatha Menon, N(Cochin University of Science and Technology, June , 2001)
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Abstract:
present work deals with the various aspects of population characteristics of penaeus indicus ,Metapenaeus dobsoni and metapenaeus monoceros during their nursery phase in tidal ponds and adjacent backwaters.Importance of the present study is to suggest scientific basis for the management of penaeid resources in tidal ponds and backwaters based on their biological characteristics to ensure better yield.Seasonal closure of fishing will be effective in improving the size of the shrimp at harvest.Hydrology of tidal ponds varied with location, but showed a common seasonal pattem.Seasonal variation in temperature was very small. It fluctuated between 27.5 to 32.3°C in tidalponds and 26.9 to 29.9°C in open backwaters.Improvement of nursery habitats with due consideration for biological requirements of the resource will ensure better growth, survival and abundance of the stock.The recruitment, growth and emigration data of prawns from their nurseries can be used successfully for fishery forecasting. projecting juvenile growth forward through time, it is possible to establish, which cohort contributes to offshore fishery each year. So, by interpreting the recruitment and growth data of species in their nurseries with offshore catch data, fishery can be forecasted successfully.
Description:
Central Marine Fisheries Research Institute, Kochi
Bindhu,Paul; George,M K(ICAR, CMFRI, November , 2000)
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Abstract:
The thesis contains the results of an investigation on the " Population Genetic Structure of the Penaeus indicus " from southeast and southwest coasts of India. The P.indicus, popularly known as the Indian white prawn, is distributed widely in the Indo-Pacific, starting from New South wales in Australia in the east to the east coast of Africa in the west. Its heavy demand in the export market, the species has been exploited intensively from all along its areas of distribution in Indian waters. The population genetic characteristics of the species were examined by three independent but complementary techniques, namely, morphometrics (truss network), biochemical genetics (isozyme electrophoresis ) and molecular genetics (RFLP and RAPD). The east and west coast populations of the species may be genetically different. Due to certain constraints, the results obtained from the studies of restriction fragment length 70 polymorphism (RFLP) were limited. The significant difference in the number of bands in the sample populations strongly suggests that these two populations have considerably different population genetic structures
Mohandas, N N; Dr.George, M K(Indian Council of Agricultural Research, Central Marine Fisheries Institute, January , 1997)
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Abstract:
The objective of present investigation was to study the population genetic structure of S. longiceps by applying three different basic population genetic techniques such as cytogenetics, non-enzymatic biochemicalgenetics (general protein) and morphomeristics/metrics.