503 research outputs found
Mass of the black hole in the Seyfert 1.5 galaxy H 0507+164 from reverberation mapping
We present the results of our optical monitoring campaign of the X-ray source
H 0507+164, a low luminosity Seyfert 1.5 galaxy at a redshift z = 0.018.
Spectroscopic observations were carried out during 22 nights in 2007, from the
21 of November to the 26 of December. Photometric observations in the R-band
for 13 nights were also obtained during the same period. The continuum and
broad line fluxes of the galaxy were found to vary during our monitoring
period. The R-band differential light curve with respect to a companion star
also shows a similar variability. Using cross correlation analysis, we
estimated a time delay of 3.01 days (in the rest frame), of the response of the
broad H-beta line fluxes to the variations in the optical continuum at 5100
angstroms. Using this time delay and the width of the H-beta line, we estimated
the radius for the Broad Line Region (BLR) of 2.53 x 10^{-3} parsec, and a
black hole mass of 9.62 x 10^{6} solar mass.Comment: 7 pages, 8 figures, Accepted for publication in MNRA
Compact steep-spectrum sources from the S4 sample
We present the results of 5-GHz observations with the VLA A-array of a sample
of candidate Compact Steep Spectrum sources (CSSs) selected from the S4 survey.
We also estimate the symmetry parameters of high-luminosity CSSs selected from
different samples of radio sources, and compare these with the larger sources
of similar luminosity to understand their evolution and the consistency of the
CSSs with the unified scheme for radio galaxies and quasars. The majority of
CSSs are likely to be young sources advancing outwards through a dense
asymmetric environment. The radio properties of CSSs are found to be consistent
with the unified scheme, in which the axes of the quasars are observed close to
the line of sight, while radio galaxies are observed close to the plane of the
sky.Comment: accepted for publication in mnras; 8 pages, figure 1 with 21 images,
and two additional figures; 2 table
Copper induces nitrification by ammonia-oxidizing bacteria and archaea in pastoral soils
CAUL read and publish agreement 2022fals
Yield and quality improvement in Bt cotton through foliar application of trifloxystrobin and tebuconazole
In agriculture, fungi can cause serious damage, resulting in critical losses of yield, quality and profit. Fungicides help in reducing the damage caused by fungus, reduce the yield loss and play a major role in quality improvement. The present investigation was carried out at Tamil Nadu Agricultural University to evaluate the influence of trifloxystrobin 50% + tebuconazole 25% (Nativo 75WG) on the yield and quality improvement on Bunny hybrid Bt cotton.  Nativo 75WG was applied on the leaves of cotton plants at 40-60 (DAS) and 60-80 (DAS) at the concentration of 250, 300, 350 g/ha and Carbendazim @ 500 g/ha. The observations recorded were related to yield and quality attributes in all treatments. The application of Nativo @ 300 g/ha showed a significant increase in boll weight (4.86 g), lint yield per boll (3.86 g boll-1) and lint per plant (138.48 g plant -1) than other treatments. With respect to seed cotton yield and harvest index (0.37 %), the Nativo @ 300 g/ha registered a higher yield (20.2 %) and HI than control under the irrigated situation. Foliar application of treatments during the flowering stage (40-60 DAS) and boll formation stages (60-80 DAS) had increased the quality parameters such as fiber length (2.5% staple length, 50 % staple length) and fiber strength. Further, the foliar spray of Nativo @ 300 g/ha applied to bunny hybrid Bt cotton had resulted in a higher yield (2920.15 kg ha-1) due to an increase in leaf area index, greenness of leaf and higher dry matter production of the plant
Mass of the black hole in the Seyfert 1.5 galaxy H 0507+164 from reverberation mapping
We present the results of our optical monitoring campaign of the X-ray source H 0507+164, a low-luminosity Seyfert 1.5 galaxy at a redshift z= 0.018. Spectroscopic observations were carried out during 22 nights in 2007, from 2007 November 21 to 2007 December 26. Photometric observations in the R band for 13 nights were also obtained during the same period. The continuum and broad-line fluxes of the galaxy were found to vary during our monitoring period. The R-band differential light curve with respect to a companion star also shows a similar variability. Using cross-correlation analysis, we estimated a time-delay of τcen= 3.01+0.42− 1.84 d (in the rest frame) of the response of the broad Hβ line fluxes to the variations in the optical continuum at 5100 Å. Using this time-delay and the width of the Hβ line, we estimated the radius for the broad-line region of 2.53+0.35− 1.55× 10−3 pc and a black hole mass of 9.62+0.33− 3.73× 106 M
Modular automated solid phase synthesis of dermatan sulfate oligosaccharides
Dermatan sulfates are glycosaminoglycan polysaccharides that serve a multitude
of biological roles as part of the extracellular matrix. Orthogonally
protected D-galactosamine and L-iduronic acid building blocks and a photo-
cleavable linker are instrumental for the automated synthesis of dermatan
sulfate oligosaccharides. Conjugation-ready oligosaccharides were obtained in
good yield
The Nitrogen Dynamics of Newly Developed Lignite-Based Controlled-Release Fertilisers in the Soil-Plant Cycle
(c) The Author/sThe effect of newly developed controlled-release fertilisers (CRFs); Epox5 and Ver-1 and two levels of Fe2+ applications (478 and 239 kg-FeSO4 ha−1) on controlling nitrogen (N) losses, were tested on ryegrass, in a climate-controlled lysimeter system. The Epox5 and Ver-1 effectively decreased the total N losses by 37 and 47%, respectively, compared to urea. Nitrous oxide (N2O) emissions by Ver-1 were comparable to urea. However, Epox5 showed significantly higher (p < 0.05) N2O emissions (0.5 kg-N ha−1), compared to other treatments, possibly due to the lock-off nitrogen in Epox5. The application of Fe2+ did not show a significant effect in controlling the N leaching loss and N2O emission. Therefore, a dissimilatory nitrate reduction and chemodenitrification pathways were not pronounced in this study. The total dry matter yield, N accumulation, N use efficiency and soil residual N were not significantly different among any N treatments. Nevertheless, the N accumulation of CRFs was lower in the first month, possibly due to the slow release of urea. The total root biomass was significantly (p < 0.05) lower for Epox5 (35%), compared to urea. The hierarchical clustering of all treatments revealed that Ver-1 outperformed other treatments, followed by Epox5. Further studies are merited to identify the potential of Fe2+ as a controlling agent for N losses.fals
Spectral ageing analysis of the double-double radio galaxy J1453+3308
We present new radio observations at frequencies ranging from 240 to 4860 MHz
of the well-known, double-double radio galaxy (DDRG), J1453+3308, using both
the Giant Metrewave Radio Telescope (GMRT) and the Very Large Array (VLA).
These observations enable us to determine the spectra of the inner and outer
lobes over a large frequency range and demonstrate that while the spectrum of
the outer lobes exhibits significant curvature, that of the inner lobes appears
practically straight. The break frequency, and hence the inferred synchrotron
age of the outer structure, determined from 16arcsec strips transverse to
the source axis, increases with distance from the heads of the lobes. The
maximum spectral ages for the northern and southern lobes are 47 and 58
Myr respectively. Because of the difference in the lengths of the lobes these
ages imply a mean separation velocity of the heads of the lobes from the
emitting plasma of 0.036c for both the northern and southern lobes. The
synchrotron age of the inner double is about 2 Myr which implies an advance
velocity of 0.1c, but these values have large uncertainties because the
spectrum is practically straight.Comment: 10 pages, 10 figures, 5 tables, accepted for publication in MNRA
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