In many of the Asian countries including India, textile industries are huge in numbers in which most of the energy requirements are met through electrical energy. The Indian energy crises, increase ...in energy cost, and product demand are the major factors, which make these textile sectors to move ahead toward the energy efficient technologies and to adopt the energy conservation techniques. In this view, a detailed energy performance study was conducted in one of the textile industries to identify the energy saving potential. This study contributes to the reduction of specific energy consumption from 3041.3 kWh/ton to 2867 kWh/ton of the product. Overall, about 1029 MWh energy consumption has been reduced which accounts 5.95% of the total energy consumed by the selected industry. The CO
2
emission reduction is 833 tCO
2
/annum. The main aim of this study is not only to reduce the specific energy consumption but also to improve the energy performance of the equipments by adopting the various energy efficient technologies and energy conservation measures in order to control the Indian energy crises.
Improper handling and discarding of metal nanoparticles into the ecosystem can lead to nano-pollution affecting the biota of the environment. This study was performed to understand the possible ...negative impacts of the silver nanoparticles for which silver nanoparticles were synthesized using plant gum from Azadirachta indica. The synthesized silver nanoparticles were characterized by UV–Visible Spectroscopy, Fourier-Transform Infrared Spectroscopy, X-ray powder Diffraction, Scanning Electron Microscopy, and Zeta Potential analysis. The silver nanoparticles were crystalline and spherical in shape and the size was found to be around 40–70 nm. The toxic effects of Azadirachta indica gum based biogenic silver nanoparticles of different concentration (10 μg and 20 μg) in vivo against Eudrilus eugeniae, Danio rerio and its embryos were assessed, where it was found to damage the epidermis of gut and clitellum of the earthworm. It was found to cause gut erosion in zebrafishes depicting the toxicity. In the case of the embryos, it delayed the embryogenesis and organ deformities were observed. As the concentration of the nanoparticles, the damage in the organisms also increased indicating that it was concentration dependent impact.
•Silver nanoparticles were produced using plant gum from Azadirachta indica.•Various characterizations were done.•Toxicity studies against Eudrilus eugeniae, Danio rerio and its embryos were done.•The ultimate objective of this study was to synthesize nanoparticles through biological method in order to reduce the toxic effects.
We describe directed searches for continuous gravitational waves in data from the sixth LIGO science data run. The targets were nine young supernova remnants not associated with pulsars; eight of the ...remnants are associated with non-pulsing suspected neutron stars. One target's parameters are uncertain enough to warrant two searches, for a total of ten. Each search covered a broad band of frequencies and first and second frequency derivatives for a fixed sky direction. The searches coherently integrated data from the two LIGO interferometers over time spans from 5.3-25.3 days using the matched-filtering F-statistic. We found no credible gravitational-wave signals. We set 95% confidence upper limits as strong (low) as \(4\times10^{-25}\) on intrinsic strain, \(2\times10^{-7}\) on fiducial ellipticity, and \(3\times10^{-6}\) on r-mode amplitude. These beat the indirect limits from energy conservation and are within the range of theoretical predictions for neutron-star ellipticities and r-mode amplitudes.
Phys. Rev. Lett. 125, 101102 (2020) On May 21, 2019 at 03:02:29 UTC Advanced LIGO and Advanced Virgo observed a
short duration gravitational-wave signal, GW190521, with a three-detector
network ...signal-to-noise ratio of 14.7, and an estimated false-alarm rate of 1
in 4900 yr using a search sensitive to generic transients. If GW190521 is from
a quasicircular binary inspiral, then the detected signal is consistent with
the merger of two black holes with masses of $85^{+21}_{-14} M_{\odot}$ and
$66^{+17}_{-18} M_{\odot}$ (90 % credible intervals). We infer that the primary
black hole mass lies within the gap produced by (pulsational) pair-instability
supernova processes, and has only a 0.32 % probability of being below $65
M_{\odot}$. We calculate the mass of the remnant to be $142^{+28}_{-16}
M_{\odot}$, which can be considered an intermediate mass black hole (IMBH). The
luminosity distance of the source is $5.3^{+2.4}_{-2.6}$ Gpc, corresponding to
a redshift of $0.82^{+0.28}_{-0.34}$. The inferred rate of mergers similar to
GW190521 is $0.13^{+0.30}_{-0.11}\,\mathrm{Gpc}^{-3}\,\mathrm{yr}^{-1}$.
We report the observation of a compact binary coalescence involving a 22.2 -
24.3 $M_{\odot}$ black hole and a compact object with a mass of 2.50 - 2.67
$M_{\odot}$ (all measurements quoted at the ...90$\%$ credible level). The
gravitational-wave signal, GW190814, was observed during LIGO's and Virgo's
third observing run on August 14, 2019 at 21:10:39 UTC and has a
signal-to-noise ratio of 25 in the three-detector network. The source was
localized to 18.5 deg$^2$ at a distance of $241^{+41}_{-45}$ Mpc; no
electromagnetic counterpart has been confirmed to date. The source has the most
unequal mass ratio yet measured with gravitational waves,
$0.112^{+0.008}_{-0.009}$, and its secondary component is either the lightest
black hole or the heaviest neutron star ever discovered in a double
compact-object system. The dimensionless spin of the primary black hole is
tightly constrained to $\leq 0.07$. Tests of general relativity reveal no
measurable deviations from the theory, and its prediction of higher-multipole
emission is confirmed at high confidence. We estimate a merger rate density of
1-23 Gpc$^{-3}$ yr$^{-1}$ for the new class of binary coalescence sources that
GW190814 represents. Astrophysical models predict that binaries with mass
ratios similar to this event can form through several channels, but are
unlikely to have formed in globular clusters. However, the combination of mass
ratio, component masses, and the inferred merger rate for this event challenges
all current models for the formation and mass distribution of compact-object
binaries.
The first observing run of Advanced LIGO spanned 4 months, from September 12, 2015 to January 19, 2016, during which gravitational waves were directly detected from two binary black hole systems, ...namely GW150914 and GW151226. Confident detection of gravitational waves requires an understanding of instrumental transients and artifacts that can reduce the sensitivity of a search. Studies of the quality of the detector data yield insights into the cause of instrumental artifacts and data quality vetoes specific to a search are produced to mitigate the effects of problematic data. In this paper, the systematic removal of noisy data from analysis time is shown to improve the sensitivity of searches for compact binary coalescences. The output of the PyCBC pipeline, which is a python-based code package used to search for gravitational wave signals from compact binary coalescences, is used as a metric for improvement. GW150914 was a loud enough signal that removing noisy data did not improve its significance. However, the removal of data with excess noise decreased the false alarm rate of GW151226 by more than two orders of magnitude, from 1 in 770 years to less than 1 in 186000 years.
The first observational run of the Advanced LIGO detectors, from September 12, 2015 to January 19, 2016, saw the first detections of gravitational waves from binary black hole mergers. In this paper ...we present full results from a search for binary black hole merger signals with total masses up to \(100 M_\odot\) and detailed implications from our observations of these systems. Our search, based on general-relativistic models of gravitational wave signals from binary black hole systems, unambiguously identified two signals, GW150914 and GW151226, with a significance of greater than \(5\sigma\) over the observing period. It also identified a third possible signal, LVT151012, with substantially lower significance, and with an 87% probability of being of astrophysical origin. We provide detailed estimates of the parameters of the observed systems. Both GW150914 and GW151226 provide an unprecedented opportunity to study the two-body motion of a compact-object binary in the large velocity, highly nonlinear regime. We do not observe any deviations from general relativity, and place improved empirical bounds on several high-order post-Newtonian coefficients. From our observations we infer stellar-mass binary black hole merger rates lying in the range \(9-240 \mathrm{Gpc}^{-3} \mathrm{yr}^{-1}\). These observations are beginning to inform astrophysical predictions of binary black hole formation rates, and indicate that future observing runs of the Advanced detector network will yield many more gravitational wave detections.
The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large velocity, highly nonlinear regime, and to witness the final ...merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (post-inspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasi-normal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parameterized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a \(90\%\)-confidence lower bound of \(10^{13}\) km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.
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