Ravisankar, M; Reghunath, A T; Sathianandan, K; Nampoori, V P N(Optical Society of America, September 15, 1988)
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Abstract:
The split-pulse laser method is used to reinvestigate the optical attenuation of distilled water in the region from 430 to 630 nm. The studies are then extended to ionic solutions of NaCl, MgCl2, and Na2SO4, these salts forming the major constituents of seawater. The effect of the concentration of these constituents on optical attenuation is investigated. Further, optical attenuation studies are carried out for the region from 430 to 630 nm for an aqueous solution prepared with all the major constituents in the same proportions as in natural seawater. These values are then compared with values obtained for natural seawater. The relative role of dissolved salts and suspended particles on optical attenuation in seawater is discussed. The lowest attenuation is observed at ~450 nm for all solutions and is found to coincide with that for distilled water.
Mohanan, T(American Institute of Physics, August 22, 2005)
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Abstract:
The effect of dopants with different valencies and ionic radii on the densification, structural
ordering, and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 (BMT) is investigated. It is
found that dopants such as Sb2O5, MnO, ZrO2, WO3, and ZnO improve the microwave dielectric
properties of BMT. Addition of trivalent dopants is detrimental to the cation ordering and dielectric
properties of BMT. A correlation between the microwave dielectric properties of BMT and ionic
radii of the dopant has been established. The variation of the dielectric properties of pure and doped
BMT at cryogenic temperatures is also discussed.
Surendran,K P; Sebastian,M T; Mohanan, P; Mohanan,Jacob V(American Institute of Physics, 2005)
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Abstract:
The effect of dopants with different valencies and ionic radii on the densification, structural
ordering, and microwave dielectric properties of Ba(Mg1t3Tazt3)O3 (BMT) is investigated. It is
found that dopants such as Sb,05, MnO, ZrO,, WO1, and ZnO improve the microwave dielectric
properties of BMT. Addition of trivalent dopants is detrimental to the cation ordering and dielectric
properties of BMT. A correlation between the microwave dielectric properties of BMT and ionic
radii of the dopant has been established. The variation of the dielectric properties of pure and doped
BMT at cryogenic temperatures is also discussed
Rani, Joseph(John Wiley & Sons, Inc., June 21, 2001)
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Abstract:
ABSTRACT: Polyaniline was synthesized by using ammonium persulfate initiator in the
presence of 1M HC1. It was dried under different drying conditions like room temperature
drying (for 48 h), oven drying (at 50-60°C for 8 h under a vacuum), and vacuum
drying (at room temperature for 16 h). The conductivities of these samples were
measured at microwave frequencies. These samples were also pelletized and the
measurements were repeated. The cavity perturbation technique was used for the
study.
Rani, Joseph(OPA (Overseas Publishers Association) N.V., July 23, 1997)
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Abstract:
Selected grades of low density polyethylene (LDPE) polystyrene (PS) were extruded in a
laboratory extruder by varying the feeding rate at different revolutions per minute and
temperatures. The mechanical properties of the extruded plastic sheets were determined.
LDPE shows a marked variation in mechanical properties with feeding rate while PS
shows a marginal change in mechanical properties with feeding rate. However, for both
plastics there is a particular feeding rate in the starved region which results in maximum
mechanical properties.
The effect of glass additives on the densification , phase evolution, microstructure and microwave dielectric properties of Ba(Mg1;3
Ta2i3)03 (BMT) was investigated . Different weight percentages of quenched glass such as B203 , Si02, B203-SiO2, ZnO-B203,
5ZnO-2B2O3, Al203-SiO2, Na20-2B203.10H20, BaO-B203-SiO2, MgO-B203-SiO2, PbO-B203-SiO2 , ZnO-B203-SiO2 and
2MgO-Al203-5SiO2 were added to calcined BMT precursor . The sintering temperature of the glass -added BMT samples were
lowered down to 1300 °C compared to solid-state sintering where the temperature was 1650 °C. The formation of high temperature
satellite phases such as Ba5Ta4O15 and Ba7Ta6O22 were found to be suppressed by the glass addition . Addition of glass systems such
as B203, ZnO-B203, 5ZnO-2B203 and ZnO-B203-SiO2 improved the densification and microwave dielectric properties. Other
glasses were found to react with BMT to form low-Q phases which prevented densification . The microwave dielectric properties of
undoped BMT with a densification of 93 . 1 % of the theoretical density were Cr = 24 . 8, Tr = 8 ppm/°C and Q„ x f= 80,000 GHz. The
BMT doped with 1.0 wt% of B203 has Q„ x f = 124,700GHz, Cr = 24.2, and T f = -1.3 ppm /°C. The unloaded Q factor of 0.2 wt%
ZnO-B203-doped BMT was 136,500 GHz while that of 1.0 wt% of 5ZnO-2B203 added ceramic was Q„ x f= 141,800 GHz . The best
microwave quality factor was observed for ZnO -B203-SiO2 (ZBS) glass-added ceramics which can act as a perfect liquid-phase
medium for the sintering of BMT. The microwave dielectric properties of 0.2wt% ZBS-added BMT dielectric was
Q„ x f= 152,800 GHz, F,= 25.5, and Tr = - 1.5 ppm/°C
Ponnachan,P T C; Paulose,C S; Panikkar, K R(Department of Biotechnology, April , 1993)
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Abstract:
Alloxan induced animal model was used to evaluate the potential antidiabetic effect of A . marmelose leaf
extract. The diabetic animals were given insulin injection and another group A . marmelose leaf extract orally.
It maintained the weight of the animals near to the control rats but a significant decrease in weight was noted it
diabetic animals without any treatment . The blood elucose level in 'treated animals were near to that of control
ones. Also a significantly increased glucose tolerance was observed in animals orally given the leaf extract
prior to the experiment . A significant decrease in liver glycogen ( 1.24 -.07 s!/ 100 g of wet tissue) was observed
in diabetic rats which was brought to almost the normal level (I.84- . 14 g; 100 g) with Icaf extract treatment.
Blood urea and serum cholesterol increased ( 62.66 - 3.50 and 192.67± 13.64 mg' dl) significantly in alloxxan
diabetic rats . The leaf extract treatment decreased the blood urea and serum . cholesterol (37.83 - 3.97 and
99?0±8.43 mg/dl ) to that of control ones . A similar effect was seen with insulin treatment . The results
indicate that the active principle in .4. marmelose leaf extract has similar hypoglycaemic activity to insulin
treatment.
Simon,Chiu; Paulose,C S; Ram,K Mishra(Department of Bio Technology, July 7, 1980)
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Abstract:
Effect of L-prolyl-cinagta tlheep spyo atenndt idaol paanmti-iPnaer/nkeinusroonleiapnti cp rreocpeeprttoiers b oifn dLi-npgrso.lyPl E-LP-TleIuDcEylS- g2l(y1c)Li n1-a0lem5u-ic1dy1el1-g,(Ply1Lc9iG8n1)a. mw-Taidhsee i nm(vPeeLcstGhiag) anotinesmd n ie onuf rb oaelchetapiovtinico -suuirnbadslu eacrnevddetnarflefetueeacrrtmto
a coephfnp ePtrmLe(2icGc0iaa, lob4 mnl0y io atndnhedevl sii8tn r0oto fem dndgosoi ppktyaag mm o-1fii nn tSeehCr/eng cteiwcau tfiracuolenle edpcptattiiioiclcny r r feienoscrp et ohfpinetvos erer ad ebtali.iyncAsdit)cienusdgit ge bin nyai dfrhimacaatli nonsttpilrseytirar aiatdtuttoimeolnn u(a3aso tmfde PidgfL f hkeGargel -o(n'p2tI0ieaPr ali)ldn.y odB ll ay4-b 0icne omldlneugtdc rk eabgdsy t - c1,aa pcSthoaCrmleo)ponfrsaicypil .heP TidLn hteGoe
pahnidn esp tior odpoepraimdoinl ew raesc aelpstoo ersx ainm tihnee dst.rPiaLtuGm s,elbeuctt ihvaedly n eon ehfafneccte don t h['eH a]ffsipniirtoyp oefr tidhoel sbpiencdifinicg .b Tinhdei nbge hoafv aigouonraislt an[3dH b] iaopcohmemori--
cal results obtained in the present study raise the possibility that PLG may facilitate nigro-striatal dopaminergic neurotransmission
through interacting with a unique PLG receptor functionally coupled to the dopamine receptor cyclase complex. -adenylate
Shenoy, S D; Joy, P A; Anantharaman, M R(Elsevier, February , 2004)
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Abstract:
Nanosized ZnFe2O4 particles containing traces of a-Fe2O3 by intent were produced by low temperature chemical
coprecipitation methods. These particles were subjected to high-energy ball milling. These were then characterised using
X-ray diffraction, magnetisation and dielectric studies. The effect of milling on zinc ferrite particles have been studied
with a view to ascertaining the anomalous behaviour of these materials in the nanoregime. X-ray diffraction and
magnetisation studies carried out show that these particles are associated with strains and it is the surface effects that
contribute to the magnetisation. Hematite percentage, probably due to decomposition of zinc ferrite, increases with
milling. Dielectric behaviour of these particles is due to interfacial polarisation as proposed by Koops. Also the defects
caused by the milling produce traps in the surface layer contributes to dielectric permittivity via spin polarised electron
tunnelling between grains. The ionic mechanism is enhanced in dielectrics with the rise in temperature which results in
the increase of dielectric permittivity with temperature.
Anantharaman, M R; Muhammad, Abdul Jamal E; Mohanan, P; Joy, P A; Philip, Kurian(Springer, May 29, 2009)
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Abstract:
Nickel–rubber nanocomposites were synthesized
by incorporating ferromagnetic nickel nanoparticles in a
natural rubber as well as neoprene rubber matrix. Complex
dielectric permittivity and magnetic permeability of
these composites were evaluated in the X-band microwave
frequencies at room temperature using cavity perturbation
technique. The dielectric loss in natural rubber is smaller
compared to neoprene rubber. A steady increase in the dielectric
permittivity is observed with increase in the content
of nickel in both the composites. The magnetic permeability
exhibits a steady decrease with increase in frequency and
magnetic loss shows a relaxation at 8 GHz. The suitability of
these composites as microwave absorbers is modeled based on the reflection loss which is dependant on the real and
imaginary components of the complex dielectric permittivity
and magnetic permeability.
One-pot acetalizations of cyclohexanone. acetophenone and benzophenone were carried out using methanol over H-montmorillonite clay
(a mesoporous material). silica, alumina, and different zeolites such as HFAU-Y.HBeta, H-ZSM-5, and H-mordenite. In all the cases a single
product-the corresponding dimethylacetal-was obtained in high yields. Hemiacetal formation was not observed with any catalyst. A
comparison of catalytic activity indicated that montmorillonite K-10 is the most active catalyst for the reaction. As evidenced by the reaction
time studies, the catalyst decay is greater over the zeolite catalyst than over the clay.
Anantharaman, M R; Vaidyanathan, G; Arulmurugan, R; Likhite, S D; Milind, Vaidya; Sendhilnathan, S; Senthilram, N D(NATL INST SCIENCE COMMUNICATION, December 12, 2003)
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Abstract:
Mixed ferrites belonging to the type Mn0.9Zn0.1Fe2O4 have been prepared by the double sintering method and by the
chemical co-precipitation for comparing their magnetic properties. Sintered and precipitated ferrites exhibit different
characteristics, especially in their magnetic properties like magnetization (Ms), coercive field (Hc) and Curie temperature
(Tc). The sintered particles were size reduced in order to compare with the nanosized co-precipitated particles. The effect of
grinding has also been studied. Particles have been collected at regular intervals of grinding and their properties have been
studied. The increase in the coercive field has been recorded by a hysteresis curve tracer confirming size reduction. X-ray
diffraction studies confirmed the structure and consequent size reduction
Description:
Indian Journal of Engineering & Materials Sciences
Vol. 11, August 2004, pp. 289-294
The effect of various processing parameters, such as nip gap, friction ratio
and roll temperature, on the tensile properties of short Kevlar aramid
fibre-thermoplastic polyurethane composite has been investigated and the tensile
and tear fracture surfaces have been characterised using a scanning electron microscope.
A nip gap of 0.45 mm, a friction ratio of 1.15 and a roll temperature of 62°C
was found to give optimum mechanical properties. Scanning electron microscopy
study revealed a higher extent of fibre orientation in the milling direction in the
above condition.
Paulose,C S; Dakshinamurti,K(Department of Biotechnology, December 19, 1984)
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Abstract:
The high-affinity bindings of [3H]-5-hydroxytryptamine to serotonin S-1 receptors,
[3H]-ketanserin to serotonin S-2 receptors in the cerebral cortex, [3H]-
fluphenazine to dopamine D-1 receptors, and [3H]-spiroperidol to dopamine D-2
receptors in the corpus striatum were studied in pyridoxine-deficient rats and
compared to pyridoxine-supplemented controls. There was a significant increase
in the maximal binding (Bmax) of serotonin S-1 and S-2 receptors with a significant
decrease in their binding affinities (Kd). However, there were no significant
changes either in the maximal binding or binding affinity of striatal dopamine D-
1 and D-2 receptors. Receptor sensitivity seems to correlate negatively with the
corresponding neurotransmitter concentrations in the pyridoxine-deficient rats.
Pyroja, S; Biju,M P; Paulose,C S(Department of Biotechnology, February 11, 1998)
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Abstract:
Effect of pyridoxine on growth, metabolism and cellular activity of
freshwater prawn Macrobrachiuni rosenbergii was studied. Postlarvae
(PL-10) of M. rosenbergii were fed with clam meat containing
various concentrations of pyridoxine. After 30 days RNA and DNA
of the abdominal tissues were estimated. Length, weight and RNA
to DNA ratio increased significantly with increasing concentrations
of pyridoxine. The effect of pyridoxine on the metabolic enzyme,
malate dehydrogenase, was also studied. Vmax showed a significant
decrease and the (Km) showed a significant increase in experimental
groups compared to control.
Litty, Irimpan; Deepthy, A; Bindu, Krishnan; Kukreja, L M; Nampoori, V P N; Radhakrishnan, P(Elsevier, 2008)
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Abstract:
In the present work, we report the third order nonlinear optical properties of ZnO thin films deposited using self assembly, sol gel process as well as pulsed laser ablation by z scan technique. ZnO thin films clearly exhibit a negative nonlinear index of refraction at 532 nm and the observed nonlinear refraction is attributed to two photon absorption followed by free carrier absorption. Although the absolute nonlinear values for these films are comparable, there is a change in the sign of the absorptive nonlinearity of the films. The films developed by dip coating and pulsed laser ablation exhibit reverse saturable absorption whereas the self assembled film exhibits saturable absorption. These different nonlinear characteristics in the self assembled films can be mainly attributed to the saturation of linear absorption of the ZnO defect states.
Sreeraj, M; Sumam, Mary Idicula(IEEE, December 7, 2012)
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Abstract:
The span of writer identification extends to broad
domes like digital rights administration, forensic expert decisionmaking
systems, and document analysis systems and so on. As the
success rate of a writer identification scheme is highly dependent
on the features extracted from the documents, the phase of
feature extraction and therefore selection is highly significant for
writer identification schemes. In this paper, the writer
identification in Malayalam language is sought for by utilizing
feature extraction technique such as Scale Invariant Features
Transform (SIFT).The schemes are tested on a test bed of 280
writers and performance evaluated