Abdul Khalam,L; Sreemoolanadhan,H; Ratheesh, R; Mohanan, P; Sebastian,M T(ELSEVIER, 2003)
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Abstract:
Microwave dielectric resonators (DRs) based on Ba(B1,2Nbi/2)03 [B' = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Y, Yb, and In] complex
perovskites have been prepared by conventional solid state ceramic route. The dielectric properties (relative permittivity, Er; quality factor, Q;
and resonant frequency, rr) of the ceramics have been measured in the frequency range 4-6 GHz using resonance methods. The resonators
have relatively high dielectric constant in the range 36-45, high quality factor and small temperature variation of resonant frequency. The
dielectric properties are found to depend on the tolerance factor (t), ionic radius (r), and lattice parameter (ap)
Mailadil,Sebastian T; Sam,Solomon; Ravindran,Ratheesh(Regional Research Laboratory, April , 1999)
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Abstract:
Microwave ceramic dielectric resonators (DRs) based on RETiNbO6
(RE = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, and Yb)
have been prepared using the conventional solid -state ceramic
route. The DR samples are characterized using XRD and SEM
methods. The microwave dielectric properties are measured
using resonant methods and a net work analyzer . The ceramics
based on Ce, Pr, Nd, and Sin have dielectric constants in the
range 32-54 and positive coefficient of thermal variation of
resonant frequency (r,). The ceramics based on Gd, Tb, Dy, Y.
and Yb have dielectric constants in the range 19-22 and
negative Tf
Prathapachandra Kurup, M R; Alex, Punnoose; Manoj, E(Elsevier, October 17, 2008)
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Abstract:
Ten new copper(II) complexes of five potential bisthiocarbohydrazone and biscarbohydrazone ligands
were synthesized and physico-chemically characterized. The spectral and magnetic studies of compounds
are consistent with the formation of asymmetric di-, tri- or tetranuclear copper(II) complexes of deprotonated
forms of respective ligands. The variable temperature magnetic susceptibility measurements of all
complexes showantiferromagnetic interactions between the Cu(II) centers, in agreement with very broad
powder EPR spectra. However, frozen solution EPR spectral studies are found in contradiction with the
solid-state magnetic studies and indicate that the complexes are not very stable in solutions; the possible
fragmentations of complexes are found in agreement with MALDI MS results. The EPR spectral simulation
of most of the compounds is in agreement with the presence of two uncoupled Cu(II) species in solution.
Mohammed Yusuff, K K; Ahmed Yasir,Vakayil; Mohan Das,P N(Elsevier, International Journal of Inorganic Materials, August 12, 2001)
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Abstract:
Highly crystalline, ultra fine TiO (anatase) having high surface area has been prepared by thermal hydrolysis of titanyl sulphate 2
solution and characterized using B.E.T surface area measurements, XRD and chemical analysis. The dependence of surface area on
concentration of staffing solution, temperature of hydrolysis, duration of boiling and calcination temperature were also studied. As the
boiling temperature, duration of boiling and calcination temperature increased, the surface area of TiO formed decreased significantly. 2
On increasing calcination temperature, the crystallite size of TiO also increased and gradually the phase transformation to rutile took 2
place. The onset and completion temperatures of rutilation were 700 and 10008C, respectively
Abhilash, G.; Dr. Rani Joseph(Cochin University of Science and Technology, August 13, 2015)
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Abstract:
Natural rubber latex, an aqueous colloidal dispersion of polyisoprene is
widely used in production of gloves, catherers, rubber bands etc. The natural
rubber latex content present in products such as gloves causes allergic
problems. Of the different types of allergies reported, latex is known to produce
Type I and Type IV allergies. Type I is called immediate hypersensitivity and
type IV is called delayed hypersensitivity. It has been reported that some of the
proteins present in the latex are mainly responsible for the allergic reactions
type I. Significant reduction in the allergic response (type I) of natural rubber
latex can be achieved by the reduction in its protein content, however out of the
total proteins present in the latex or latex film only a fraction is extractable. The
major techniques employed to reduce protein content of latex include leaching,
autoclaving, chlorination, use of proteolytic enzymes and use of non ionic
surfactants. Sulphur vulcanization of dipped products is responsible for Type
IV allergy. N-nitrosamine, a carcinogenic substance is produced as a result of
sulphur vulcanization. Radiation vulcanization can be used as an alternative for
sulphur vulcanization.
The current research deals with techniques to reduce the allergy
associated with latex products. To reduce the type I allergy, low protein
latex is developed using polyethylene glycol, a non- ionic surfactant. The
present study employs radiation vulcanization to eliminate type IV allergy.
The effect of different cure systems and fillers on the properties of low
protein latex is also investigated as a part of the study.
Low-protein content natural rubber latex
was produced by using a nonionic surfactant-polyethylene
glycol (PEG). Extractable protein content of natural rubber
latex was found to decrease with PEG treatment and
reduction increased with increase in the molecular weight
of PEG. The low-protein latex samples were characterized
by tensile testing, Fourier transform infrared and thermogravimetric
analysis. The results have shown 35% reduction in the extractable protein content, without any compromise
on the mechanical properties of the latex; however,
thermal stability of low-protein latex was found to be
reduced marginally with PEG treatment.
Deepa, K G; Dr.Sudha Kartha,C(Cochin University of Science & Technology, August , 2008)
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Abstract:
In this work. Sub-micrometre thick CulnSe2 films were prepared using different
techniques viz, selenization through chemically deposited Selenium and Sequential
Elemental Evaporation. These methods
are simpler than co-evaporation technique, which is known to be the most suitable
one for CulnSe2 preparation. The films were optimized by varying the composition
over a wide range to find optimum properties for device fabrication. Typical absorber
layer thickness of today's solar cell ranges from 2-3m. Thinning of the absorber
layer is one of the challenges to reduce the processing time and material usage,
particularly of Indium. Here we made an attempt to fabricate solar cell with absorber
layer of thickness <lmum. Here In2S3 was used as the buffer layer, replacing toxic CdS.
Description:
Department of Physics,
Cochin University of Science and Technology
Kochu Baby, Manjooran S; Dr.Kuriakose, A P(Cochin University of Science and Technology, April 15, 1998)
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Abstract:
Petroleum, a mixture of organic compounds, comes from
underground rock formations ranging in age from ten to several
hundred million years. The process by which it is formed and
developed is not yet completely known. Studies indicate that petroleum
is formed mainly from microscopic-sized marine animals and plants.
When these organisms died in water of low oxygen content, they
did not decompose. Thus their remains sank to the bottom to
be buried under accumulations of sediment. Their conversion to petroleum remains a subject of research even today.
Description:
Department of Polymer Science and Rubber Technology,
Cochin University of Science and Technology
Navas, K A; Dr.Mathew, K J(Cochin University of Science and Technology, March , 1993)
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Abstract:
Coral Reefs are marine, biogenic, wave resistant carbonate structures,
formed of the skeletal remains of hermatypic, or reef building organisms.
The main reef builders are calcifying Rhodophytes, molluscs, sponges, polychaetes and Cnidarians. Among them, scleractinian corals and hydrocorallians are by far the most important contributors to the formation of reefs. Coral reefs cover approximately 600 thousand square kilometers of the earth's surface (Crossland fl a_1., 1991) which is about 2x106 square kilometres of tropical oceans.
Sebastian, Paul; Sebastian,V D(School of Legal Studies, July , 1996)
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Abstract:
This study analyses the role of the Press Council as
a champion and guard of free speech. It discusses the
extent to which the Council succeeded in achieving its
statutory objective of preserving the freedom of the
press and maintaining and improving the standards of
newspapers and news agencies. It also examines the
inherent and in-built weaknesses of the Council and
suggests ways and means for restructuring and enlarging
its functions.
Padma, Nambisan; Jasmin, Koshy(IJPAES, April 5, 2012)
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Abstract:
Bioethanol is a liquid fuel obtained from fermentation of sugar/starch crops. Lignocellulosic
biomass being less expensive is considered a future alternative for the food crops. One of the main
challenges for the use of lignocellulosics is the development of an efficient pre-treatment process.
Pretreatments are classified into three - physical, chemical, and biological pretreatment. Chemical process
has not been proven suitable so far, due to high costs and production of undesired by-products.
Biologically, hydrolysis can be enhanced by microbial or enzymatic pretreatment. Studies show that the
edible mushrooms of Pleurotus sp. produce several extracellular enzymes which reduce the structural and
chemical complexity of fibre. In the present study, P. ostreatus and P. eous were cultivated on paddy straw.
Spent substrate left after mushroom cultivation was powdered and used for ethanol production.
Saccharomyces sp. was used for fermentation studies. Untreated paddy straw was used as control.
Production of ethanol from P. ostreatus substrate was 5.5 times more when compared to untreated paddy
straw, while the spent substrate of P. eous gave 5 times increase in ethanol yield. Assays showed the
presence of several extracellular enzymes in the spent substrate of both species, which together contributed
to the increase in ethanol yield
Description:
International Journal of Plant, Animal and Environmental Sciences,vol 2,issue 2,april-june 2012
Prevalence and antibiotic resistance of Escherichia coli in the water and sediment samples
of brackish water aquaculture ponds adjacent to Cochin backwaters was analysed. More
than 50% of the water samples and more than 80% of sediment samples from all the sampling
stations were tested positive for £. coli. Risk assessment of the E. coli strains was carried
out using multiple antibiotic resistance (MAR) indexing. Majority of the strains were found
to be multiple antibiotic resistant suggesting their origin from high risk sources of
contamination such as human where antibiotics are frequently used. While none of the £.
coli strains were resistant against amikacin, chloramphenicol, streptomycin and trimethoprim,
considerable levels of resistance was encountered against ampicillin, erythromycin,
penicillin G and vancomycin. High prevalence of £. coli in the water and sediment samples
of this extensive brackish water ponds indicates high degree of faecal pollution of this
environment. The high risk nature of the strains warrants efficient post harvest and processing
measures to avoid health risk to consumers
Hatha, A A M; Suresh, T; Sreenivasan, D; Nathan, Sangeetha; Lakshmanaperumalsamy, P(Elsevier, April 8, 2005)
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Abstract:
A study was conducted to determine the incidence of Salmonella enterica serovar Enteritidis and other Salmonella serovars on
eggshell, egg contents and on egg-storing trays. A total of 492 eggs and 82 egg-storing trays were examined over a period of 1 year
from different retail outlets of a residential area of Coimbatore city, South India. Salmonella contamination was recorded in 38 of
492 (7.7%) eggs out of which 29 was in eggshell (5.9%) and 9 in egg contents (1.8%). Around 7.5% of the egg-storing trays were also
found to be contaminated with Salmonella. Serotyping of the Salmonella strains showed that 89.7% of the strains from eggshell,
100% of the strains from egg contents and 71.4% of the strains from egg-storing trays were Salmonella Enteritidis. Other
serovarvars encountered were S. Cerro, S. Molade and S. Mbandaka from eggshell and S. Cerro from egg-storing trays. Seasonal
variations in the prevalence pattern were identified with, a higher prevalence during monsoon months followed by post-monsoon
and premonsoon. Further examination of the Salmonella strains was carried out by testing their antimicrobial sensitivity against 10
commonly used antimicrobials. Results revealed high prevalence of multiple antimicrobial resistance among these strains suggesting
possible prior selection by use of antimicrobials in egg production
Hatha, A A M; Lakshmanaperumalsamy, P; Suresh, T; Nathan, Sangeetha; Sreenivasan, D(Elsevier, April 8, 2005)
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Abstract:
A study was conducted to determine the incidence of Salmonella enterica serovar Enteritidis and other Salmonella serovars on
eggshell, egg contents and on egg-storing trays. A total of 492 eggs and 82 egg-storing trays were examined over a period of 1 year
from different retail outlets of a residential area of Coimbatore city, South India. Salmonella contamination was recorded in 38 of
492 (7.7%) eggs out of which 29 was in eggshell (5.9%) and 9 in egg contents (1.8%). Around 7.5% of the egg-storing trays were also
found to be contaminated with Salmonella. Serotyping of the Salmonella strains showed that 89.7% of the strains from eggshell,
100% of the strains from egg contents and 71.4% of the strains from egg-storing trays were Salmonella Enteritidis. Other
serovarvars encountered were S. Cerro, S. Molade and S. Mbandaka from eggshell and S. Cerro from egg-storing trays. Seasonal
variations in the prevalence pattern were identified with, a higher prevalence during monsoon months followed by post-monsoon
and premonsoon. Further examination of the Salmonella strains was carried out by testing their antimicrobial sensitivity against 10
commonly used antimicrobials. Results revealed high prevalence of multiple antimicrobial resistance among these strains suggesting
possible prior selection by use of antimicrobials in egg production
Hatha, A A M; Lakshmanaperumalsamy, P; Suresh, T; Harsha, H T(Elsevier, January 18, 2011)
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Abstract:
Broiler chicken is gaining popularity among the consumers of India. Since poultry is recognised as a leading food
vehicle for Salmonella contamination, the prevalence and distribution of Salmonella serotypes in broiler chickens
and processing environments of retail outlets has been studied. In the present study 214 samples of broiler
chicken and 311 environmental samples from cage were analysed for the presence of Salmonella. Of the various
body parts of live chicken analysed prevalence varied from 1.4% in cloacca to 6.9% in crop region. Environmental
samples from the cage showed higher prevalence of Salmonella ranging from0 to 16.67%. Apart from Salmonella
enteritidis, which was the predominant Salmonella serotype in the chickens as well as in the environmental
samples, other serotypes such as S. bareilly, S. cerro, S. mbandaka and S. moladewere also encountered. The results
of the research calls for strict hygiene standards for retail broiler chicken processing outlets
Hatha, A A M; Nifty, John(Indian J. Fish, February 29, 2012)
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Abstract:
The objective of the present study was to assess the prevalence of various motile aeromonads in freshwater ornamental fishes
and to elucidate the antibiogram and beta hemolytic activity among the isolates. A total of 120 ornamental fish samples were
screened and analyzed for Aeromonas spp. Motile aeromonads were isolated from 37.5% of the ornamental fish samples.
Various species of motile aeromonads such as Aeromonas caviae, Aeromonas hydrophila, Aeromonas jandaei, Aeromonas
schubertii, Aeromonas sobria, Aeromonas trota and Aeromonas veronii were detected. All the isolates were sensitive to
ceftazidime, chloramphenicol, ciprofloxacin and gentamicin. Multiple antibiotic resistance was observed in 58% of the
isolates.
Hatha, A A M; Vivekanandhan, G; Lakshmanaperumalsamy, P(Elsevier, January 26, 2004)
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Abstract:
Five hundred and thirty six samples offishes and 278 prawn samples from the major fish market ofCoimbatore, South India,
were analysed for the prevalence of Aeromonas hydrophila over a period of2 years (June 1997–May 1999). The prevalence level of A.
hydrophila varied from 17.62% in prawns to 33.58% in fishes. More than 30% of the popular table fishes such as Sardinella
longiceps, Rastrelliger kanagurta, Mugil cephalus and Caranx sexfasciatus were tested positive for this organism. Among the
different species of the prawns analysed, Penaeus semisulcatus showed higher incidence (23.52%). Seasonal variation in the
prevalence levels of A. hydrophila in fish and prawns revealed a higher prevalence during the monsoon season during 1997–98 and
1998–99. Of the different body parts of the fishes analysed for A. hydrophila, the intestinal samples showed higher prevalence
(38.43%), followed by body surface (32.46%) and gill (29.10%). Considering the psychrotrophic nature and role of A. hydrophila as
a pathogen ofemerging importance, the considerably high levels ofthis organism in a popular food item such as fish and prawn
raises serious concern