15 research outputs found
Cosmological evolution in a two-brane warped geometry model
We study an effective 4-dimensional scalar-tensor field theory, originated
from an underlying brane-bulk warped geometry, to explore the scenario of
inflation. It is shown that the inflaton potential naturally emerges from the
radion energy-momentum tensor which in turn results into an inflationary model
of the Universe on the visible brane that is consistent with the recent results
from the Planck's experiment. The dynamics of modulus stabilization from the
inflaton rolling condition is demonstrated. The implications of our results in
the context of recent BICEP2 results are also discussed.Comment: 11 pages, Latex style, 4 eps figures and 1 tabl
Synthesis, Spectroscopic, and Antimicrobial Studies of Binuclear Metallocene (M = Ti, Zr, or Hf) Derivatives of Bis(mercaptoazoles)
The reactions of (η5 − C5H5)2MCl2 (M = Ti, Zr, or Hf) with mercaptoazoles (LH2), namely, bis(mercaptotriazoles), bis(mercap- tooxadiazoles),
and bis(mercaptothiadiazoles) in 2 : 1 molar ratio, respectively, have been studied in dry tetrahydrofuran in
the presence of n-butylamine and the binuclear complexes of the type [{(η − C5H5)2 M}2(L)] (M = Ti/Zr/Hf) are obtained. Tentative structural conclusions are drawn for the reaction
products based upon elemental analysis, electrical conductance, magnetic moment, and spectral
data (UV-Vis, IR, 1H NMR, and 13C NMR). FAB-mass spectra of few complexes of each series were also carried out to
confirm the binuclear structures. Studies were conducted to assess the growth-inhibiting
potential of the complexes synthesized, and the ligands against various fungal and bacterial strains
Oxovanadium(IV) complexes with 14-membered macrocyclic ligands derived from dithiooxamide
644-647Oxovanadium(lV) complexes, [VO(L)] SO4'where L = 5,7,12, 14-R4-2, 3, 9, 10-S4‑[14]-1, 5, 7, 12-tetraene- 1,4,8, Ll-N4 have been prepared in methanol. Tentative structures of the complexes have been proposed on the basis of elemental analyses, electrical conductance, magnetic moment and spectral (JR, electronic and EPR) data. The X-band EPR spectra of all the complexes were recorded at room temperature and at liquid nitrogen temperature. The room temperature EPR spectra do not show anisotropy because of rapid tumbling of the molecules in solution but it is observed at liquid nitrogen temperature. The spectral studies support square pyramidal geometry for the oxovanadium (IV) complexes
Synthesis and spectroscopic investigations of oxovanadium(IV) derivatives with 1,1ʹ-diacetylferrocenyl-bis(hydrazones)
1906-1910The reactions of oxovanadium(IV) sulphate
with bis(hydrazones) (LH2) derived from 1,1ʹ-diacetylferrocene and different
aromatic acid/pyridine carboxylic acid hydrazides, in ethanol gives the complexes
of type [VO(L)]. Tentative structural
conclusions are drawn for the complexes based
upon analyses, conductance, magnetic moments and spectral (IR , electronic and EPR)
data
Lanthanum(III) and praseodymium(III) complexes with bidentate and tetradentate schiff base ligands containing indole ring
1198-1201Complexes
of lanthanum(III) and praseodymium(III) with schiff bases, prepared from isatin with aniline,
4-chloroanilinc, 2-bromoaniline, 2-nitroaniline (HL), ethylenediamine, o-phenylenediamine and 4-methyl-o-phenylenediamine
(H2L') have been synthesised
and their physico-chemical
properties investigated
using elemental analysis, molar conductivities,
magnetic susceptibility
measurements and spectral (visible, infrared and 1H NMR) data. The schiff bases H2L' bind in
a bidentate manner while schiff bases H2L' bind in
a tetradentate
manner. The probable
structures of the complexes
are proposed
Oxovanadium(IV) complexes with unsymmetrical macrocyclic ligands derived from <i>o</i>-bromoaniline, <i>α </i>-or <i>β</i>-diketones and primary diamines
887-890A new series
of N4-donor unsymmetrical oxovanadium (IV) complexes of type [VO(mac)]SO4
(mac = macrocyclic ligands derived from o-bromoaniline, α -or β-diketones
and aliphatic diamines e.g. ethylenediamine or 1 ,3-propylenediamine ) have
been prepared by template synthesis. Tentative structures of the complexes have
been proposed on the basis of elemental analysis, electrical conductance, magnetic
moment and spectral (IR.
electronic and
EPR) data. The X-band EPR spectra of all the complexes have been recorded at
room temperature and at liquid N2 temperature. The room temperature EPR
spectra do not show anisotropy because of rapid tumbling of molecules in solution.
The spectral studies support square-pyramidal geometry for the vanadium(IV) complexes
Template synthesis and spectroscopic studies on oxovanadium(IV) acyclic and macrocyclic complexes
447-451The template reactions of 2,6-diaminopyridine or 1,8-diaminonaphthalene with diacetyl or benzil in the presence of vanadyl(IV) produce N3O2 or N2O2 open chain complexes as a result of [2+1] schiff base condensation. These complexes contain free ketonic group. Therefore, the reactions of these complexes with diamines (o-phenylenediamine and 4-methyl-o-phenylenediamine) have been studied in presence of glacial acetic acid which cause ring closure and formation of macrocyclic complexes. The complexes so obtained have been characterized on the basis of elemental analysis, conductance, magnetic moment and spectral (electronic, IR and ESR) data. The probable structures of the complexes are suggested
Synthesis and characterization of acetylferrocenyl thiosemicarbazone derivatives of dichlorobis(cyclopentadienyl)hafnium(IV)
1421-1423The
reactions of Cp2HfCl2 with thiosemicarbazones (LH) derived
from acetylferrocene and substituted thiosemicarbazide (phenyl/4-chlorophenyl/4-ni
tropheny1/4-methylphenyl thiosemicarbazide) in various stoichiometric ratios
have been studied and the complexes of the type [Cp2HfCl(L)] are
obtained. Tentative structural conclusions are drawn for the reaction products
based upon elemental analyses, electrical conductance, magnetic moment and
spectral data (UV -Vis, IR, 1H NMR and
13C NMR)