653 research outputs found
Photo-excitation of a light-harvesting supra-molecular triad: a Time-Dependent DFT study
We present the first time-dependent density-functional theory (TDDFT)
calculation on a light harvesting triad carotenoid-diaryl-porphyrin-C60.
Besides the numerical challenge that the ab initio study of the electronic
structure of such a large system presents, we show that TDDFT is able to
provide an accurate description of the excited state properties of the system.
In particular we calculate the photo-absorption spectrum of the supra-molecular
assembly, and we provide an interpretation of the photo-excitation mechanism in
terms of the properties of the component moieties. The spectrum is in good
agreement with experimental data, and provides useful insight on the
photo-induced charge transfer mechanism which characterizes the system.Comment: Accepted for publication on JPC, March 09th 200
Synthesis, characterization and thermal decomposition of M1[M2(C2O4)2].xH2O (x=5 for M1=Co and x=4 for M1=Cd;M2=Ni
Cobalt bis(oxalato)nickelate pentahydrate, Co[Ni(C2O4)2]×5H2O and cadmium bis(oxalato)nickelate
tetrahydrate, Cd[Ni(C2O4)2]×4H2O have been synthesized and characterized by elemental analysis,
reflectance and IR spectral studies. Thermal decomposition studies (TG, DTG and DTA ) in air
showed that both the compound of cobalt and cadmium produced the oxide, MNiOx (x=3 for M=Co;
x=2 for M=Cd ) at 325 and 360°C respectively. DSC studies in nitrogen attributed only the mixture
of both the metal at the end
Attenuation of coda waves in the Northeastern Region of India
Coda wave attenuation quality factor
Qc is estimated in the northeastern region of India
using 45 local earthquakes recorded by regional
seismic network. The quality factor Qc was estimated
using the single backscattering model modified
by Sato (J Phys Earth 25:27–41, 1977), in
the frequency range 1–18 Hz. The attenuation and
frequency dependence for different paths and the
correlation of the results with geotectonics of the
region are described in this paper. A total of 3,890
Qc measurements covering 187 varying paths are
made for different lapse time window of 20, 30, 40,
50, 60, 70, 80, and 90 s in coda wave. The magnitudes
of the analyzed events range from 1.2 to 3.9
and focal depths range between 7 and 38 km. The
source–receiver distances of the selected events
range between 16 and 270 km. For 30-s duration,
the mean values of the estimated Qc vary from
50 ± 12 (at 1 Hz) to 2,078 ± 211(at 18 Hz) for the Arunachal Himalaya, 49 ± 14 (at 1 Hz) to
2,466 ± 197 (at 18 Hz) for the Indo-Burman, and
45 ± 13 (at 1 Hz) to 2,069 ± 198 (at 18 Hz) for
Shillong group of earthquakes. It is observed
that Qc increases with frequency portraying
an average attenuation relation Qc = 52.315 ±
1.07 f (1.32±0.036) for the region. Moreover, the pattern
of Qc−1 with frequency is analogous to the
estimates obtained in other tectonic areas in the
world, except with the observation that the Qc−1
is much higher at 1Hz for the northeastern region.
The Qc−1 is about 10−1.8 at 1 Hz and decreases to
about 10−3.6 at 18 Hz indicating clear frequency
dependence. Pertaining to the spatial distribution
of Qc values, Mikir Hills and western part
of Shillong Plateau are characterized by lower
attenuation
Attenuation of coda waves in the Northeastern Region of India
Coda wave attenuation quality factor
Qc is estimated in the northeastern region of India
using 45 local earthquakes recorded by regional
seismic network. The quality factor Qc was estimated
using the single backscattering model modified
by Sato (J Phys Earth 25:27–41, 1977), in
the frequency range 1–18 Hz. The attenuation and
frequency dependence for different paths and the
correlation of the results with geotectonics of the
region are described in this paper. A total of 3,890
Qc measurements covering 187 varying paths are
made for different lapse time window of 20, 30, 40,
50, 60, 70, 80, and 90 s in coda wave. The magnitudes
of the analyzed events range from 1.2 to 3.9
and focal depths range between 7 and 38 km. The
source–receiver distances of the selected events
range between 16 and 270 km. For 30-s duration,
the mean values of the estimated Qc vary from
50 ± 12 (at 1 Hz) to 2,078 ± 211(at 18 Hz) for the Arunachal Himalaya, 49 ± 14 (at 1 Hz) to
2,466 ± 197 (at 18 Hz) for the Indo-Burman, and
45 ± 13 (at 1 Hz) to 2,069 ± 198 (at 18 Hz) for
Shillong group of earthquakes. It is observed
that Qc increases with frequency portraying
an average attenuation relation Qc = 52.315 ±
1.07 f (1.32±0.036) for the region. Moreover, the pattern
of Qc−1 with frequency is analogous to the
estimates obtained in other tectonic areas in the
world, except with the observation that the Qc−1
is much higher at 1Hz for the northeastern region.
The Qc−1 is about 10−1.8 at 1 Hz and decreases to
about 10−3.6 at 18 Hz indicating clear frequency
dependence. Pertaining to the spatial distribution
of Qc values, Mikir Hills and western part
of Shillong Plateau are characterized by lower
attenuation
The effects of attenuation and site on the spectra of microearthquakes in the Jubilee Hills region of Hyderabad, India
Potentilla fulgens Wall
ABSTRACT The paper highlights some of the most important Ayurvedic medicinal plants of North Eastern India having anticancer potential. A brief review of distribution and pharmacological study (both in vivo and in vitro) of ten Ayurvedic medicinal plants of the region published by various researchers is illustrated in this paper. The medicinal plants discussed here are Enhydra Fluctuans Lour (Sanskrit: Hilamochika), Ageratum conizoides Linn
Super congruences and Euler numbers
Let be a prime. We prove that
, where E_0,E_1,E_2,... are Euler numbers. Our new approach is of
combinatorial nature. We also formulate many conjectures concerning super
congruences and relate most of them to Euler numbers or Bernoulli numbers.
Motivated by our investigation of super congruences, we also raise a conjecture
on 7 new series for , and the constant
(with (-) the Jacobi symbol), two of which are
and
\sum_{k>0}(15k-4)(-27)^{k-1}/(k^3\binom{2k}{k}^2\binom{3k}k)=K.$
Stabilization of Cuo-nanoparticles into the nanopores of modified montmorillonite: An implication on catalytic approach for "Click" reaction between azides and terminal alkynes
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