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The “Dead Universe” Theory: Natural Separation of Galaxies Driven by the Remnants of a Supermassive Dead Universe
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作者 Joel Almeida 《Natural Science》 2024年第6期65-101,共37页
This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This per... This article explores the dead universe theory as a novel interpretation for the origin and evolution of the universe, suggesting that our cosmos may have originated from the remnants of a preceding universe. This perspective challenges the conventional Big Bang theory, particularly concerning dark matter, the expansion of the universe, and the interpretation of phenomena such as gravitational waves. 展开更多
关键词 Dead universe Theory Heat Death of the universe Big Bang Theory universe’s Ultimate Fate universe Expansion Big Freeze universe Cosmological Models End of universe Theories Natural Galaxy Drift Future of the universe universe cooling down Cosmology and Entropy
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Effect of Ag substitution on structural,magnetic and magnetocaloric properties of Pr_(0.6)Sr_(0.4–x)Ag_xMnO_3 manganites 被引量:4
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作者 R.Thaljaoui M.Pekala +1 位作者 J.-F.Fagnard Ph.Vanderbemden 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第9期875-882,共8页
A systematic investigation on the structural, magnetic and magnetocaloric properties of Pr_(0.6)Sr_(0.4-x)Ag_xMnO_3(x=0.05 and 0.1) manganites was reported. Rietveld refinements of the X-ray diffraction patterns... A systematic investigation on the structural, magnetic and magnetocaloric properties of Pr_(0.6)Sr_(0.4-x)Ag_xMnO_3(x=0.05 and 0.1) manganites was reported. Rietveld refinements of the X-ray diffraction patterns confirmed that all samples were single phase and crystallized in the orthorhombic structure with Pnma space group. Magnetic measurements in a magnetic applied field of 0.01T revealed that the ferromagnetic-paramagnetic transition temperature T_C decreased from about 293 to 290 K with increasing silver content from x=0.05 to 0.1. The reported magnetocaloric entropy change and relative cooling power for both samples were considerably remarkable with a △S_(max) value of 1.9 J/(kg·K)and maximum RCP values of 100 J/kg, under a magnetic field change(?μ0H) equal to 1.8T. The analysis of the universal curves gave an evidence of a second order magnetic transition for the studied samples. The magnetic field influence on both the magnetic entropy change and the relative cooling power was also studied and discussed. 展开更多
关键词 monovalent doped manganite XRD SEM ZFC and FC curves mgnetocaloric effect universal curves relative cooling power critical exponents
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