Anantharaman, M R; Lisha, R; Hysen, T; Geetha, P; Avasthi, D K; Ramanujan, R V(IOP Publishing LTD, March 7, 2014)
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Abstract:
Metglas 2826 MB having a nominal composition of Fe40Ni38Mo4B18 is an
excellent soft magnetic material and finds application in sensors and memory
heads. However, the thin-film forms of Fe40Ni38Mo4B18 are seldom studied,
although they are important in micro-electro-mechanical systems/nano-electromechanical
systems devices. The stoichiometry of the film plays a vital role in
determining the structural and magnetic properties of Fe40Ni38Mo4B18 thin
films: retaining the composition in thin films is a challenge. Thin films of 52 nm
thickness were fabricated by RF sputtering technique on silicon substrate from a
target of nominal composition of Fe40Ni38Mo4B18. The films were annealed at
temperatures of 400 °C and 600 °C. The micro-structural studies of films using
glancing x-ray diffractometer (GXRD) and transmission electron microscope
(TEM) revealed that pristine films are crystalline with (FeNiMo)23B6 phase.
Atomic force microscope (AFM) images were subjected to power spectral
density analysis to understand the probable surface evolution mechanism during
sputtering and annealing. X-ray photoelectron spectroscopy (XPS) was
employed to determine the film composition. The sluggish growth of crystallites
with annealing is attributed to the presence of molybdenum in the thin film. The
observed changes in magnetic properties were correlated with annealing induced
structural, compositional and morphological changes
Manoj, N(American chemical society, August 7, 2006)
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Abstract:
A combined experimental and theoretical study of the absorption spectra of a group of closely related pyrylium
perchlorates 1-11 are presented. Minor changes in the position of the substituents lead to drastic changes in
the absorption spectra in this series of compounds. We have attempted to explain the observed changes using
the x,y-band notation developed by Balaban and co-workers. Absorption spectra of all compounds are compared
with results from time-dependent density functional theory (TDDFT) and Zerner’s intermediate neglect of
differential overlap (ZINDO/S) level calculations. Results of the calculations are in good agreement with
experimental observations and an interesting correlation between Balaban’s notations and the MO transitions
are obtained for simple derivatives. It is suggested that for more complex systems such as R- and â-naphthyl
substituted systems, the empirical method is not appropriate.
Bindhu, C V; Harilal, S S; Nampoori, V P N; Vallabhan, C P G(Journal of Physics D: Applied Physics, 1999)
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Abstract:
Dual-beam transient thermal lens studies were carried out in aqueous solutions of
rhodamine 6G using 532 nm pulses from a frequency-doubled Nd:YAG laser. The analysis of
the observed data showed that the thermal lens method can effectively be utilized to study the
nonlinear absorption and aggregation which are taking place in a dye medium.
Rani, Joseph(Hitthig & Wepf Verlag, Basel, October 13, 1986)
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Abstract:
A carbon black filled 50/50 natural rubber (NR)/styrene-butadiene rubber (SBR)
blend is vulcanized using several conventional curing systems designed by varying the
amounts of sulphur and accelerator. The cure characteristics and the properties of the
vulcanizates are compared. The quantity and quality of crosslinks in each case are
evaluated by chemical probes to correlate them with the properties.
Sunil,K Narayanankutty(Sage Publications, April , 2002)
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Abstract:
Cure characteristics and mechanical properties of acrylonitrile
butadiene rubber/reclaimed rubber blends were studied. Minimum torque,
(ma)dmum -minimum) torque, scorch time, cure time and cure rate decreased in
presence of reclaimed rul3ber. Tensile strength, elongation at break and
compression set increased'with increase in reclaim content. Resilience and
abrasion resistance decreased with reclaim loading. Heat build up was higher for
the blends. The ageing resistance of the blends was inferior to that of the gum
compound.
Sunil,K Narayanankutty(Sage Publications, April , 2002)
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Abstract:
Acrylonitrile butadiene rubber (NBR) matrix was reinforced with
different levels of short nylon fiber loading. Cure characteristics and mechanical
properties of composites in longitudinal and transverse directions have been
studied. Cure time was reduced while processability, as indicated by the
minimum torque, was marginally reduced with increase in fiber loading. Tensile
and tear properties improved with fiber concentration and the values were
higher in longitudinal direction of fiber orientation. Abrasion resistance,
resilience and compression set were increased in presence of fibers. Elongation
at break values showed a drastic drop on introduction of fibers. Heat build up
was higher for composites.
This paper discusses the salient features associated with the variation in the BODs
and dissolved oxygen concentration in the Kadinamkulam Kayal based on fortnightly
data from two selected stations from October1987toSeptember1988.The BODs ranged
from 5.76 to 24.39 mg/l in the surface water and from 4.96 to 22.60mg!1 in the bottom
waterat station-l whereas at station-2, it ranged from 0 to 3.74mg/1 in the surface water
and from 0 to 3.40 mg!l in the bottom water. The dissolved oxygen concentration
ranged from 0 to 0.72 mglI in the surface water and from 0 to 0.42 mg!l in the bottom
waterat station-I, At station-2 it ranged from 2.69 to 6.21mg!1 in the surface waterand
from 1.97 to 5.74 mg!1 in the bottom water. The pre-monsoom period showed the
highest BODsof 16.68mg!I while the monsoon period showed the lowest of 0.61 mg!I.
The dissolved oxygen concentration reached its peak during the monsoon period (5.52
mg/I). Long spells of anoxic condition during the post and pre-monsoon periods was
a characteristic feature of the retting zone
Description:
MAHASAGAR
Vol.23, No.2 (December), 1990, pp. 95-101
Rani, Joseph(John Wiley & Sons,Inc., December 29, 1997)
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Abstract:
ABSTRACT: The electrical conductivity of silicone rubber vulcanizates containing carbon
blacks [e.g., acetylene black, lamp black, and ISAF (N-234) black] were investigated.
The change in electrical conductivity with varying amounts of carbon blacks and the
temperature dependence was measured. The mechanical properties like tensile
strength, tear strength, elongation at break, hardness, etc., of the vulcanizates were
determined. A comparative study of the electrical conductivity of the composites revealed
that the electrical conductivity of the composites made with acetylene black was
higher than that of the composites made of other blacks.
Achamma, Kurian; Nibu, A George; Binoy, Paul; Nampoori, V P N; Vallabhan, C P G(Taylor & Francis, 2002)
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Abstract:
In this paper we report the use of the dual beam thermal lens technique as a quantitative
method to determine absolute fluorescence quantum efficiency and concentration
quenching of fluorescence emission from rhodamine 6G doped Poly(methyl
methacrylate) (PMMA), prepared with different concentrations of the dye. A
comparison of the present data with that reported in the literature indicates that the
observed variation of fluorescence quantum yield with respect to the dye
concentration follows a similar profile as in the earlier reported observations on
rhodamine 6G in solution. The photodegradation of the dye molecules under cw laser
excitation is also studied using the present method.
Carbon Black is incorporated In natural rubber latex in , the presence of
polyethylene glycol. The dispersion of carbon blade in the vulcanizatea is
analyzed using polaroid M.4 land camera The mechanical properties of the
carbon black meeterbatched NR/SBR blend Is compared with that of conventional
NR/SBR blend before and after ageing , The resilience, flex resistance
and hardness are found to be superior for N-LCMISBR compounds.
The compression set and abrasion resistance are comparable for both types
of blends . The processebiity and die swell of these blends at different shear
rates are also compared.
Blends of Acrylonitrile rubber with Maleic anhydride grafted Whole Tyre
Reclaim WTR (MA-g-WTR) have been prepared and the cure and mechanical
properties have been studied with respect to reclaim content. Control
compounds containing unmodified WTR were also prepared for comparison.
Grafting was confirmed by IR studies. Blends containing grafted WTR showed
higher minimum torque and (max-min) torque. They also showed longer cure
time, scorch time and lower cure rate. Grafting of the WTR with maleic
anhydride also resulted in the improved tensile strength, abrasion resistance,
compression set and resilience. However, the heat build up under dynamic
loading was marginally higher for the blends containing grafted reclaimed
rubber.
Paraphenylenediamine and diphenylamine were chemically
attached to natural rubber during mastication . The rubber bound antioxidants
were characterized by TLC, 'H-NMR, IR and TGA. The efficiency and
permenance of these bound antioxidants were compared with a conventional
amine type antioxidant in filled natural rubber vulcanizates . The rubber
bound antioxidants were found to be less volatile and less extractable as compared
to conventional antioxidants. The vulcanizates showed improved ageing
resistance as compared to vulcanizates containing conventional antioxidants.
This semisolid rubber bound antioxidant can reduce the amount of plasticizer
required for compounding.
Rani, Joseph(Elsevier Science Limited, July 3, 1994)
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Abstract:
Diphenylamine was chemically attached to depolymerised natural rubber by
photochemical reaction. The rubber-bound diphenylamine was characterised
by TLC, HNMR, IR and TGA. The efficiency and permanence of the bound
diphenylamine was compared with conventional amine type antioxidant in
natural rubber vulcanizates. The rubber-bound diphenylamine was found to be
less volatile and less extractable compared to the conventional antioxidant.
The vulcanizates showed improved ageing resistance in comparison to vulcanizates
containing conventional antioxidant . Also, the presence of liquid
rubber-bound diphenylamine reduces the amount of plasticiser required for
compounding.
Para-phenylenediamine (PD) was chemically attached to depolymerized natural rubber by
a photochemical reaction . The rubber bound PD was characterized by TLC, 1H-NMR, IR,
and TGA. The efficiency and permanence of the bound PD were compared with conventional
antioxidants in NBR vulcanizates . The rubber bound PD was found to be less volatile and
more resistant to water and oil extraction . The vulcanizates showed improved aging resistance
in comparison to vulcanizates containing conventional antioxidants. The liquid rubber
bound antioxidant reduces the amount of plasticizer required for compounding
Studies conducted on butadiene-acrylonitrile copolymer (NBR)/poly(vinyl chloride) (PVC)
blends at different temperatures indicate that an optimum temperature exists for the formation
of a particular blend. The mechanical properties of the blends confirm this observation.
PVC stabilizer based on, magnesium oxide , zinc oxide, and stearic acid was found to be very
useful in NBR/PVC blends.
Rani, Joseph(Huthig & Wepf Verlag, Basel, June 5, 1991)
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Abstract:
Antioxidants were attached to hydroxy-terminated liquid natural rubber by modified
Friedel-Crafts alkylation reaction using anhydrous zinc chloride as catalyst. The rubber
bound antioxidants were found to be less volatile and less extractable compared to
conventional antioxidants. The bound antioxidants were tried both in latex compounds
and dry rubber compounds. The vulcanizates showed improved ageing resistance
compared to vulcanizates based on conventional antioxidants.
Rani, Joseph(John Wiley & Sons,Inc., July 31, 1998)
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Abstract:
ABSTRACT: Nylon tire cord (1680/2) was dipped in different adhesives based on resorcinol
formaldehyde resin and latex (RFL) and was bonded to natural rubber-based
compounds. The resin-rubber ratio in the RFL adhesive was optimized. The variation
of pull-through load was studied by varying the drying and curing temperature of the
dipped nylon tire cord. RFL adhesive based on vinylpyridine latex was found to have
better rubber-to-nylon tire cord bonding, compared with the one based on natural
rubber latex. Addition of a formaldehyde donor into the RFL adhesive/rubber compound
improves adhesion.
Mohammed Yusuff, K K; Mayadevi, S; Preetha, G Prasad(Taylor & Francis, May 5, 2003)
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Abstract:
Two series of transition metal complexes of Schiff bases derived from
quinoxaline-2-carboxaldehyde with semicarbazide (QSC) and furfurylamine
(QFA) were synthesised and characterised by elemental analyses,
molar conductance and magnetic susceptibility measurements, IR, electronic
and EPR spectral studies. The QSC complexes have the general
formula [M(QSC)Cl2]. A tetrahedral structure has been assigned for the
Mn(II), Co(II) and Ni(II) complexes and a square-planar structure for the
Cu(II) complex. The QFA complexes have the formula [M(QFA)2Cl2].
An octahedral structure has been assigned for these complexes. All of
the complexes exhibit catalytic activity towards the oxidation of 3,5-di-tert-butylcatechol (DTBC) to 3,5-di-tert-butylquinone (DTBQ) using
atmospheric oxygen. The cobalt(II) complex of the ligand QFA was
found to be the most active catalyst.