Jacob S.,Cochin University of Science and Technology |
Suma K.K.,Cochin University of Science and Technology |
Suma K.K.,Maharajas college |
Mendez J.M.,Cochin University of Science and Technology |
And 2 more authors.
Materials Science and Engineering B: Solid-State Materials for Advanced Technology | Year: 2010
Polymer composites reinforced by both the micro and nano fillers is the subject of this paper. Polypropylene (PP)-nylon micro-fibre composites modified with nanosilica and modified nanosilica (using silane coupling agent) were prepared by melt compounding. The nanosilica prepared in the laboratory was used as reinforcing filler in PP-nylon fibre composites. The compounding characteristics and mechanical properties of the composites were studied. The equilibrium torque during compounding increased with the addition of nanosilica and modified nanosilica. The use of two types of fillers leads to synergistic effect on the mechanical properties of the composite. Composites with 1 wt.% nanosilica and 30 wt.% nylon fibre show high tensile strength, tensile modulus, flexural strength and flexural modulus. Composites modified with 1 wt.% nanosilica and 10 wt.% nylon fibre-PP composite show higher impact strength. © 2009 Elsevier B.V. All rights reserved.
Vinayasree S.,Cochin University of Science and Technology |
Vinayasree S.,Government Victoria College |
Soloman M.A.,St Alberts College |
Sunny V.,P.A. College |
And 3 more authors.
Composites Science and Technology | Year: 2013
Flexible and thin single layer microwave absorbers based on strontium ferrite-carbon black-nitrile rubber composites have been fabricated employing a specific recipe and their reflection loss characteristics were studied in the S (2-4. GHz) and X-bands (8-12. GHz). The incorporation of carbon black not only reinforces the rubber by improving the mechanical properties of the composite but also modifies the dielectric permittivity of the composite. Strontium ferrite when impregnated into a rubber matrix imparts the required magnetic permeability to the composite. The combination of strontium ferrite and carbon black can then be employed to tune the microwave absorption characteristics of the resulting composite. The complex dielectric permittivity and permeability were measured by employing a cavity perturbation technique. The microwave absorption characteristics of composites were modelled in that an electromagnetic wave incident normally on the metal terminated single layer absorber. The influence of filler volume fraction, frequency, absorber thickness on the bandwidth of absorption are discussed and correlated. © 2013 Elsevier Ltd.
Princy K.F.,St Alberts College |
Manomi S.,Cochin University of Science and Technology |
Philip R.,Cochin University of Science and Technology |
Gopinath A.,Kerala University of Fisheries and Ocean Studies
Nano Biomedicine and Engineering | Year: 2016
Utilization of renewable marine resources for the biosynthesis of metal nanoparticles is an innovative area in the current nanotechnology research. The present article reports a simple environmentally benign method for the synthesis of silver nanoparticles using aqueous extract of marine brown seaweed Padina Tetrastromatica, which act as both the reducing and stabilising agent. The formation, morphology and crystalline nature of the synthesised silver nanoparticles were determined using UVVisible Spectroscopy, Transmission electron microscopy, Selected area electron diffraction and X-ray diffraction techniques. The surface plasmon resonance peak at 424 nm in the UV-Visible spectrum confirmed the formation of silver nanoparticles. The biosynthesised silver nanoparticles were almost spherical with an average size of 15 nm. Crystalline nature of silver nanoparticles is evident from the characteristic peaks in the X-ray diffraction pattern, bright circular spots in the selected area electron diffraction pattern and clear lattice fringes in the High resolution Transmission electron microscopy images. Fourier transform infrared spectroscopic analysis revealed the presence of functional bio active metabolites in seaweed extract which is responsible for the formation and efficient stabilization of the nanoparticles. The biosynthesised silver nanoparticles show excellent antimicrobial activity against Escherichia coli and Aeromonas hydrophila. They also show very good catalytic activity for the reduction of methylene blue in the presence of NaBH4 in aqueous medium. Thus the green synthesised nanoparticles are expected to be a promising candidate for the application in diverse fields. © 2016 Kaithavelikkakath Francis Princy, Sarasan Manomi, Rosamma Philip and Anu Gopinath.
Antony. A A.A.,St Alberts College |
Nampy S.,University of CalicutKerala
Phytotaxa | Year: 2014
Capsule and seed morphology of 26 species of Murdannia in India are studied using light microscopy and seeds of 23 species by scanning electron microscopy. The capsules show differences in size, shape and in the number and arrangement of seeds in the locules. The seeds also display considerable variation in size, shape, ornamentation, shape of hilum and position of embryotega. The present study provides useful characters for the delimitation of Indian species of Murdannia. © 2014 Magnolia Press.
Fung A.W.S.,University of Alberta |
Ebhardt H.A.,University of Alberta |
Ebhardt H.A.,ETH Zurich |
Krishnakumar K.S.,CNRS Institute of Molecular and Supramolecular Chemistry and Biochemistry |
And 5 more authors.
Protein and Peptide Letters | Year: 2014
Aminoacyl-tRNA protein transferases post-translationally conjugate an amino acid from an aminoacyl-tRNA onto the N-terminus of a target polypeptide. The eubacterial aminoacyl-tRNA protein transferase, L/F transferase, utilizes both leucyl-tRNALeu and phenylalanyl-tRNAPhe as substrates. X-ray crystal structures with substrate analogues, the minimal substrate phenylalanyl adenosine (rA-Phe) and inhibitor puromycin, have been used to characterize tRNA recognition by L/F transferase. However analyses of these two X-ray crystal structures reveal significant differences in binding. Through structural analyses, mutagenesis, and enzymatic activity assays, we rationalize and demonstrate that the substrate analogues bind to L/F transferase with similar binding affinities using a series of different interactions by the various chemical groups of the analogues. Our data also demonstrates that enlarging the hydrophobic pocket of L/F transferase selectively enhances puromycin inhibition and may aid in the development of improved inhibitors for this class of enzymes. © 2014 Bentham Science Publishers.
West J.A.,University of Melbourne |
Kamiya M.,Fukui Prefectural University |
Ganesan E.K.,University of the East Venezuela |
de Goer S.L.,11 Rue des Moguerou |
Jose L.,St Alberts College
Algae | Year: 2015
Caloglossa species occurs in freshwater streams around Southest Asia. We report it from 2 different riverine sites in Kerala, India. Tetrasporangiate plants were observed in field collections from the Periyar River and Chalakkudy River The Chalakkudy isolate did not reproduce in culture but the Periyar isolate developed abundant tetrasporangial sori in culture. Many spores were discharged and most were abortive, but some germinated normally, sporelings forming male gametophytes with numerous spermatangial sori and females with many procarps, viable carposporophytes and some nonfunctional (no carpospores) pseudocystocarps. Some carpospores germinated forming new tetrasporophytes. Molecular evidence (28S rDNA and rbcL) placed the Indian specimens close to C. beccarii and C. fluviatilis. Considering the freshwater habitat and morphology of vegetative thalli (blade shape, rhizoid arrangement, and number of rhizoid filament per cell), the Indian specimens should be assigned to C. beccarii. © 2015 The Korean Society of Phycology.
Ginson J.,St Alberts College |
Panda S.K.,Central Institute of Fisheries Education |
Bindu J.,Central Institute of Fisheries Education |
Kamalakanth C.K.,Central Institute of Fisheries Education |
Srinivasa Gopal T.K.,Central Institute of Fisheries Education
Food Microbiology | Year: 2015
High pressure treatment of 250MPa for 6min at 25°C was applied to headless Indian white prawn (Fenneropenaeus indicus) to evaluate changes in microbiological characteristics of the species during chilled storage. Changes in load of mesophilic bacteria, psychrotrophic bacteria, proteolytic bacteria, Enterobacteriaceae, Pseudomonas spp., H2S producing bacteria, lactic acid bacteria, Brochothrix thermosphacta and yeast & mold were estimated in pressurized and un-pressurized samples during chilled storage. All microbes were reduced significantly after high pressure treatment and there was significant difference in microbial quality of control and high pressure treated samples in the entire duration of chilled storage (p<0.05). There was delay in the growth of Enterobacteriaceae and H2S producing bacteria up to 6th and 9th day of storage, respectively in high pressure treated samples. In high pressure treated sample, no lag phase (λ) was observed for psychrotrophic bacteria, H2S producing bacteria, B. thermosphacta, Pseudomonas spp. and lactic acid bacteria; however, other bacteria showed a reduced lag phase during chilled storage. Kinetic parameter such as specific growth rate (μmax) in high pressure treated samples was significantly reduced in most of the bacterial groups except for psychrotrophic bacteria, Enterobacteriaceae and lactic acid bacteria. Mesophilic bacterial count of control samples crossed the marginal limit of acceptability on 12th day and unacceptable limit on 18th day of storage, whereas high pressure treated samples never breached the acceptability limit during entire duration of chilled storage. The present study indicated that application of high pressure processing can be used to improve microbial quality of Indian white prawn and extend the chilled storage life. © 2014 Elsevier Ltd.
Fernandez S.,St Alberts College
AIP Conference Proceedings | Year: 2010
The major hurdle of a city planning council is to handle the traffic jam problem. The number of vehicles on roads increases day by day. Also the number of vehicles is directly proportional to the width of the road (including that of parallel roads). But it is not always possible to make roads or to increase width of the road corresponding to the increase in the number of vehicles. Also we cannot tell a person not to buy a vehicle. So trying to minimise the traffic jam is the only possible way to overcome this hurdle. Here we try to develop a method to avoid traffic jam through a mathematical approach (through fuzzy applications). This method helps to find a suitable route from an origin to a destination with lesser time than other routes. © 2010 American Institute of Physics.
Jose L.,St Alberts College |
Kumar C.,St Alberts College
Nature Environment and Pollution Technology | Year: 2011
The present study has been made to evaluate the organic pollution level of four temple ponds of Mattancherry Taluk in Ernakulam district. The Palmer's algal index showed that all the four ponds have high organic pollution. Algae found in the ponds belonged to Chlorophyceae, Cyanophyceae, Euglenophyceae and Bacillariophyceae. Atoxic bloom forming algae Microcystis aeruginosa was observed in three ponds. The physico-chemical analysis data supported the Palmer's organic pollution index.
Priyadarshini S.,Indian Institute of Chemical Technology |
Amal Joseph P.J.,St Alberts College |
Lakshmi Kantam M.,Indian Institute of Chemical Technology
Tetrahedron | Year: 2014
Synthesis of N-aryl-γ-amino-γ-lactams by oxidative coupling of aromatic amines with 2-pyrrolidinone using catalytic amount of CuO nanoparticles is described. The procedure has broad substrate scope, good yields, complete regioselectivity and catalyst recyclability. © 2014 Elsevier Ltd.