Results 1 to 10 of about 17,981 (269)

Using Multivariate Imputation by Chained Equations to Predict Redshifts of Active Galactic Nuclei

Frontiers in Astronomy and Space Sciences, 2022
Redshift measurement of active galactic nuclei (AGNs) remains a time-consuming and challenging task, as it requires follow up spectroscopic observations and detailed analysis.
Spencer James Gibson, Aditya Narendra, Maria Giovanna Dainotti, Maria Giovanna Dainotti, Malgorzata Bogdan, Malgorzata Bogdan, Agnieszka Pollo, Agnieszka Pollo, Artem Poliszczuk, Enrico Rinaldi, Enrico Rinaldi, Enrico Rinaldi, Ioannis Liodakis   +12 more
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Optical Characteristics of Electromagnetic Radiation, Emitted by Particles or Stars Moving near Supermassive Black Hole

Galaxies, 2021
The general problem of calculating of the propagation of electromagnetic radiation from particles or stars moving in the vicinity of a supermassive black hole is considered in geometrical optics approximation within the framework of the general theory of
Stanislav Komarov
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Electromagnetic Waves in Cosmological Spacetime

Universe, 2023
We consider the propagation of electromagnetic waves in the Friedmann–Lemaître–Robertson–Walker metric. The exact solutions for plane and spherical wave are written down. The corresponding redshift, amplitude change, and dispersion are discussed. We also
Denitsa Staicova, Michail Stoilov
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A Modified Vilsmeier–Haack Strategy to Construct β-Pyridine-Fused 5,10,15,20-Tetraarylporphyrins

SynOpen, 2020
A modified Vilsmeier–Haack strategy has been developed to construct a novel series of π-extended nickel(II) or copper(II) complexes of 2-chloro-3-formyl- and 3-formylpyrido[2,3-b]porphyrins from 2-acetamido-meso-tetraarylporphyrins. After chromatographic
Pargat Singh, Mahendra Nath
doaj   +1 more source

Does Lorentz Relativistic Mass Make Dark Energy Superfluous?

Universe, 2022
This paper shows that a simple and relativistic extension of Newtonian gravity that takes into account Lorentz relativistic mass leads to predictions that fit supernova observations of magnitude versus redshift without the need to introduce dark energy ...
Espen Gaarder Haug
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The age of our universe [PDF]

Hemijska Industrija, 2008
If we assume that the observed Redshift of starlight is due to the Doppler effect we end up with models of the universe which contradict the basic laws of science. If we assume that the red shift may be due to a tiring of light, an assumption still to be
Levenspiel Octave
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Measurement methods for gamma-ray bursts redshifts

Frontiers in Astronomy and Space Sciences, 2023
In the era of multi-messenger astronomy, gamma-ray bursts (GRBs) with known redshifts, especially high-redshift GRBs, are a powerful tool for studying the structure and evolution of the early Universe.
Mengci Li, Mengci Li, Zhe Kang, Chao Wu, Chengzhi Liu, Chengzhi Liu, Jirong Mao, Jirong Mao, Zhenwei Li, Shiyu Deng, Shiyu Deng, Bingli Niu, Bingli Niu, Ping Jiang, Ping Jiang   +14 more
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Coelenterazine Indicators for the Specific Imaging of Human and Bovine Serum Albumins

Sensors, 2023
Albumin assays in serum are important for the prognostic assessment of many life-threatening diseases, such as heart failure, liver disease, malnutrition, inflammatory bowel disease, infections, and kidney disease. In this study, synthetic coelenterazine
Sung-Bae Kim, Genta Kamiya, Tadaomi Furuta, Nobuo Kitada, Shojiro A. Maki   +4 more
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A Theoretical Study of Interband Absorption Spectra of Spherical Sector Quantum Dots under the Effect of a Powerful Resonant Laser

Nanomaterials, 2023
We explore the variation of interband absorption spectra of GaAs spherical sector quantum dots (QDs) in response to a strong resonant laser, using the renormalized wave function method. Even though a spherical sector QD appears identical to a section cut
Le Thi Dieu Hien, Le Thi Ngoc Bao, Duong Dinh Phuoc, Hye Jung Kim, C. A. Duque, Dinh Nhu Thao   +5 more
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Hydrogen Intramolecular Stretch Redshift in the Electrostatic Environment of Type II Clathrate Hydrates from Schrödinger Equation Treatment

Applied Sciences, 2020
The one-dimensional Schrödinger equation, applied to the H2 intramolecular stretch coordinate in singly to quadruply occupied large cages in extended Type II (sII) hydrogen clathrate hydrate, was solved numerically herein via potential-energy scans from ...
Christian J. Burnham, Zdenek Futera, Zlatko Bacic, Niall J. English   +3 more
doaj   +1 more source