Sudha Kartha,C(Taylor and francis, March 13, 2005)
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Abstract:
A new photopolymerizable recording media is introduced based on poly
(vinyl alcohol) and vinyl acetate sensitized with methylene blue. It is observed
that this MBPVA/VAc system can be reused a number of times without
significant decrease in diffraction efficiency. The PVA-VAc ratio was optimized
at 2:1. Diffraction efficiency of 6.3% was obtained without any fixing at a dye
concentration of 9.3 10 4 mol/l at an exposure of 750 mJ/cm2. The material is
attractive on account of its reusability.
A new photopolymerizable recording media is introduced based on poly
(vinyl alcohol) and vinyl acetate sensitized with methylene blue. It is observed
that this MBPVA/VAc system can be reused a number of times without
significant decrease in diffraction efficiency. The PVA-VAc ratio was optimized
at 2:1. Diffraction efcienc4y of 6.3% was obtained without any fixing at a dye
concentration of 9.3 x 10- mol/l at an exposure of 750mJ/cm2. The material is
attractive on account of its reusability.
A new photopolymerizable recording media is introduced based on poly
(vinyl alcohol) and vinyl acetate sensitized with methylene blue. It is observed
that this MBPVA/VAc system can be reused a number of times without
significant decrease in diffraction efficiency. The PVA-VAc ratio was optimized
at 2:1. Diffraction efcienc4y of 6.3% was obtained without any fixing at a dye
concentration of 9.3 x 10- mol/l at an exposure of 750mJ/cm2. The material is
attractive on account of its reusability.
A new photopolymerizable recording media is introduced based on poly
(vinyl alcohol) and vinyl acetate sensitized with methylene blue. It is observed
that this MBPVA/VAc system can be reused a number of times without
significant decrease in diffraction efficiency. The PVA-VAc ratio was optimized
at 2:1. Diffraction efcienc4y of 6.3% was obtained without any fixing at a dye
concentration of 9.3 x 10- mol/l at an exposure of 750mJ/cm2. The material is
attractive on account of its reusability.
In Vembanad Lake and its confluent rivers (Kerala, India), the catches of Macrobrachium rosenbergii (de Man) were reported
to have dwindled to a mere 39 t in the 1980s from average landings of 300 t during the 1960s. This decline is due to the impact
of a number of human interventions affecting the ecosystem and, hence, the stocks of M. rosenbergii. Monitoring of landings in
1994-1995 and 1995-1996 indicates an improvement in catches. This paper discusses the reasons for the decline and revival
in stocks and suggestions for their replenishment.
Asha, A S; Dr.Jayaraj, M K(Cochin University of Science & Technology, December , 2007)
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Abstract:
The main objective of this thesis work is to optimize the growth conditions for
obtaining crystalline and conducting Lao.5Sro.5Co03 (LSCO) and
Lao.5Sro.5Coo.5.5Nio.5O3 (LSCNO) thin films at low processing temperatures. The
films are prepared by radio frequency magnetron sputtering under various
deposition conditions. The thin films were used as electrodes for the fabrication
of ferroelectric capacitors using BaO.7SrO.3 Ti03 (BST) and PbZro.52 Tio.4803 (PZT).
The structural and transport properties of the La1_xSrxCo03 and Lao.5Sro.5Co1_xNix03
are also investigated. The characterization of the bulk and the thin films were
performed using different tools. A powder X-ray diffractometer was used to
analyze the crystalline nature of the material. The transport properties were
investigated by measuring the temperature dependence of resistivity using a four
probe technique. The magnetoresistance and thermoelectric power were also used to investigate the transport properties. Atomic force microscope was used
to study the surface morphology and thin film roughness. The ferroelectric
properties of the capacitors were investigated using RT66A ferroelectric tester.
Description:
Department of Physics,
Cochin University of Science and Technology
ABSTRACT: The rheological and extrudate behaviour of natural rubber/latex
reclaim blends were evaluated using a capillary viscometer . The study shows
that the viscosity of natural rubber decreases marginally on the addition of
latex reclaim while the variation of viscosity with shear rate is not affected.
The temperature sensitivity of the blends is not affected significantly with the
addition of latex reclaim . The extrudates of natural rubber/latex reclaim
blends are smooth up to the addition of about 50 wt. percent latex reclaim in
filled natural rubber compounds.
Sunil K Narayanankutty(Taylor & Francis Inc., August 23, 2004)
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Abstract:
The rheological characteristics of short Nylon-6 fiber-reinforced Styrene
Butadiene rubber (SBR) in the presence of epoxy resin-based bonding agent were
studied with respect to the effect of shear rate, fiber concentration , and temperature
on shear viscosity and die swell using a capillary rheonzeter. All the composites
containing bonding agent showed a pseudoplastic nature, which decreased
with increasing temperature. Shear viscosity was increased in the presence of
fibers. The temperature sensitivity of the SBR matrices was reduced on introduction
of fibers. The temperature sensitivity of the melts was found to be lower at
higher shear rates. Die swell was reduced in the presence of fibers. Relative viscosity
of the composites increased with shear rate. In the presence of epoxy resin
bonding agent the temperature sensitivity of the mixes increased. Die swell was
larger in the presence of bonding agent.
Sankar, T V; Ramachandran, A(John Wiley & Sons, 2002)
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Abstract:
The gel strength, compressibility and folding characteristic of suwari (set) and kamaboko (set and cooked) gels prepared from rohu (Labeo rohita), catla (Catla catla) and mrigal (Cirrhinus mrigala) surimi were examined to understand the occurrence of suwari and modori phenomena in surimi from major freshwater carps. Suwari setting of gels did not take place at lower temperatures. Suwari gels showed good gel strength at 50 °C for rohu and at 60 °C for catla and mrigal after 30 min setting time. Incubation for 60 min decreased the gel strength at 60 °C for rohu and catla. Setting at 25 °C followed by cooking at 90 °C increased the gel strength. Increased setting temperature, however, decreased the gel strength of cooked gels. Gel strength and compressibility data were supported by folding characteristics.
The rheological behavior of a short-polyester-fiber-filled polyurethane
elastomer composite containing different bonding agents
has been studied in the temperature range 120-160°C and in the
shear rate range 63-608 s-'. The composite with and without
bonding agents showed a pseudoplastic behavior which decreased
with the increase of temperature. Composites containing bonding
agents based on polypropyleneglycol and 4,4'-diphenylmethanediisocyanate
showed the lowest viscosity values at a particular
shear rate, whereas composites containing a glycerol- (GL) based
bonding agent showed the highest viscosity. The viscosity of the
composite decreased sharply after a particular temperature (140°C) and the fall was less drastic in the composite containing
a GL-based bonding agent.
Sunil K Narayanankutty(Taylor & Francis Inc., 2005)
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Abstract:
The rheological characteristics of short Nylon-6 fiber reinforced styrene butadiene
rubber (SBR) were studied using a capillary rheometer. The study was done with
respect to the effect of shear rate, fiber concentration, and temperature on shear
viscosity and die swell. All the melts showed pseudoplastic nature, which
decreased with increasing temperature. Shear viscosity increased in the presence
of fibers. Introduction of fiber reduces the temperature sensitivity of the rubber
matrix. A reduction in die swell was found in presence of fibers.
Fully burnt rice hull (rice hull ash) was tried as a low cost filler in place of precipitated
silica in NBR/PVC based microcellular soles. The mechanical properties of the soles
containing silica and ash are found to be comparable. The expansion is marginally
higher in the presence of ash, which permits to reduce the amount of blowing agent. Cell
structure of microcellular sheets remains unchanged when silica is replaced by ash.
Beyer,G J; Hagebo,E; Novgorodov,A F; Ravn,H L(EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH, November 7, 2002)
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Abstract:
On line isotope separation techniques (ISOL) for production of ion beams of short-lived radionuclides
require fast separation of nuclear reaction products from irradiated target materials followed by a transfer into
an ion source. As a first step in this transport chain the release of nuclear reaction products from refractory
metals has been studied systematically and will be reviewed. High-energy protons (500 - 1000 MeV) produce
a large number of radionuclides in irradiated materials via the nuclear reactions spallation, fission and
fragmentation. Foils and powders of Re, W, Ta, Hf, Mo, Nb, Zr, Y, Ti and C were irradiated with protons
(600 - 1000 MeV) at the Dubna synchrocyclotron, the CERN synchrocyclotron and at the CERN PS-booster
to produce different nuclear reaction products.
The main topic of the paper is the determination of diffusion coefficients of the nuclear reaction products
in the target matrix, data evaluation and a systematic interpretation of the data. The influence of the ionic
radius of the diffusing species and the lattice type of the host material used as matrix or target on the
diffusion will be evaluated from these systematics. Special attention was directed to the release of group I, II
and III-elements. Arrhenius plots lead to activation energies of the diffusion process.
Nampoori, V P N; Kamalasanan, M N; Patel, M M(IOP, 1975)
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Abstract:
Indium monofluoride was excited in a high-frequency discharge and the C-X system was photographed at a reciprocal dispersion of 0.3 AA mm-1 using a plane-grating spectrograph. Rotational analyses of the 0,0 1,0 2,2 3,3 4,4 2,4 3,5 4,6 and 5,7 bands have been carried out and the following molecular constants have been evaluated. Be'=0.2670(+or-3) cm-1, Be"=0.2628(+or-4) cm-1, alpha e'=0.0050(+or-4) cm-1, alpha e"=0.0020(+or-1) cm-1, De'=3.65(+or-5)*10-7 cm-1, De"=2.5(+or-3)*10-7 cm-1, beta e'=0.5(+or-2)*10-7 cm-1, beta e"=0.2(+or-1)*10-7 cm-1, re'=1.9672(+or-3) AA, re"=1.9853(+or-2) AA. The re" value agrees with the microwave absorption value 1.9854 AA.
Rani, Joseph(John Wiley & Sons. Inc, August 20, 1998)
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Abstract:
ABSTRACT: Rubber seed oil was used as a multipurpose ingredient in natural rubber
(NR) and styrene butadiene rubber (SBR) compounds. The study shows that the oil,
when substituted for conventional plasticiser, imparts excellent mechanical properties
to NR and SBR vulcanizates. Further, it also improves aging resistance, reduces cure
time, increases abrasion resistance and flex resistance, and reduces blooming.
Rani, Joseph(John Wiley & Sons, Inc., October 22, 1997)
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Abstract:
Rubber solutions were prepared and used for bonding wood pieces. The
effect of the variation of chlorinated natural rubber (CNR) and phenolformaldehyde
(PF) resin in the adhesive solutions on lap shear strength was determined. Natural
rubber and neoprene-based adhesive solutions were compared for their lap shear
strength. The storage stability of the adhesive prepared was determined. The change
in lap shear strength before and after being placed in cold water, hot water, acid,
and alkali was tested. The bonding character of these adhesives was compared with
different commercially available solution adhesives. The room-temperature aging
resistance of wood joints was also determined. In all the studies, the adhesive prepared
in the laboratory was found to be superior compared to the commercial adhesives.