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Related papers: Amorphous High Density Plutonium

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We present calculations of the free-free XUV opacity of warm, solid-density aluminum at photon energies between the plasma frequency at 15 eV and the L-edge at 73 eV, using both density functional theory combined with molecular dynamics and…

Plasma Physics · Physics 2009-04-02 S. M. Vinko , G. Gregori , B. Nagler , T. J. Whitcher , M. P. Desjarlais , R. W. Lee , P. Audebert , J. S. Wark

Vacuum heat treatment of mechanically-alloyed powders of boron and aluminum leads to formation of a metastable Al-rich phase, which can be quenched. Its structure, composition, and thermal stability are established. With chemical formula…

Hydrodynamic simulations of Lyman alpha clouds based on ab inito cosmological models have produced results that are in broad agreement with observations. However, further analyses have revealed that, with progressively higher numerical…

Astrophysics · Physics 2009-10-31 Renyue Cen , Greg L. Bryan

Employing first principles parallel tempering molecular dynamics in the microcanonical ensemble, we report the presence of a clear solid-liquid-like melting transition in Al20+ clusters, not found in experiments. The phase transition…

Materials Science · Physics 2015-06-23 Udbhav Ojha , Krista G. Steenbergen , Nicola Gaston

Plutonium metal exhibits an anomalously large softening of its bulk modulus at elevated temperatures that is made all the more extraordinary by the finding that it occurs irrespective of whether the thermal expansion coefficient is…

Materials Science · Physics 2020-03-25 N. Harrison

We explore the molecular beam epitaxy synthesis of superconducting aluminum thin films grown on c-plane sapphire substrates at cryogenic temperatures of 6 K and compare their behavior with films synthesized at room temperature. We…

The high-pressure behaviour of PbS was investigated by angular dispersive X-ray powder diffraction up to pressures of 6.8 GPa. Experiments were accompanied by first principles calculations at the density functional theory level. By…

Materials Science · Physics 2009-11-07 K. Knorr , L. Ehm , M. Hytha , B. Winkler , W. Depmeier

Utilizing the high-resolution, large-scale LAOZI cosmological simulations we investigate the nature of the metal-poor (${\rm [Z/H]<-2}$) damped Lyman alpha systems (mpDLA) at $z=3$. The following physical picture of mpDLAs emerges. The…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-25 Sihan Yuan , Renyue Cen

Abridged: We study the properties of clumps formed in three-dimensional weakly magnetized magneto-hydrodynamic simulations of converging flows in the thermally bistable, warm neutral medium (WNM). We find that: (1) Similarly to the…

Astrophysics · Physics 2015-05-13 Robi Banerjee , Enrique Vazquez-Semadeni , Patrick Hennebelle , Ralf Klessen

A series of electronic and structural transitions are predicted in molten lithium from first principles. A new phase with tetrahedral local order characteristic of $sp^3$ bonded materials and poor electrical conductivity is found at…

Materials Science · Physics 2009-07-09 Isaac Tamblyn , Jean-Yves Raty , Stanimir A. Bonev

The onset of quartetting, i.e. alpha-particle condensation, in symmetric nuclear matter is studied with the help of an in-medium modified four nucleon equation. It is found that at very low density quartetting wins over pairing, because of…

Nuclear Theory · Physics 2008-09-04 Y. Funaki , T. Yamada , H. Horiuchi , G. Röpke , P. Schuck , A. Tohsaki

(Pu) has an unusually rich phase diagram that includes seven distinct solid state phases and an unusually large 25% collapse in volume from its delta phase to its low temperature alpha phase via a series of structural transitions. Despite…

Strongly Correlated Electrons · Physics 2019-09-11 N. Harrison , J. B. Betts , M. R. Wartenbe , F. F. Balakirev , S. Richmond , M. Jaime , P. H. Tobash

Near 20.48K and in the temperature range 60--70K, anomalous behavior of thermodynamic, spectral, plastic, elastic and other properties of solid methane is observed. The anomalies in the vicinity of 20.48K are due to the phase $\alpha-\beta$…

Materials Science · Physics 2017-09-12 A. V. Leont'eva , A. Yu. Zakharov , A. Yu. Prokhorov

One of the prominent decay modes of heavy nuclei which are produced in astrophysical environments at temperatures of the order of $10^9$ K is the $\alpha$ ($^4$He) decay. Thermally enhanced $\alpha$ decay rates are evaluated within the…

Nuclear Theory · Physics 2022-12-09 J. E. Perez Velasquez , O. L. Caballero , N. G. Kelkar

Pulsed Laser Deposition allows to obtain W and W-Ta alloy coatings with different nanostructures, monitored by X-ray diffraction. The correlation between such structures and the elastic properties is investigated for amorphous-like,…

Materials Science · Physics 2017-10-24 E. Besozzi , D. Dellasega , A. Pezzoli , C. Conti , M. Passoni , M. G. Beghi

Re-entrant melting (in which a substance's melting point starts to decrease beyond a certain pressure) is believed to be an unusual phenomenon. Among the elements, it has so far only been observed in a very limited number of species, e.g.,…

Materials Science · Physics 2020-05-06 Qi-Jun Hong , Axel van de Walle

Inelastic $\alpha$ scattering on 16O is studied at 400 MeV by using an ice target. Near the 4-alpha breakup threshold of 14.4 MeV, a broad peak is observed at an excitation energy of 13.6+/-0.2 MeV with a width of 0.6+/-0.2 MeV. The…

Diblock copolymers by virtue of the chemical dissimilarity between the constituting blocks exhibit microphase separation in the melt state. The phase separated melt can successfully be exploited to control the morphology of the final semi…

Soft Condensed Matter · Physics 2018-02-19 Chitrita Kundu , Nikhil S. Joshi , Ashok Kumar Dasmahapatra

The physical properties of plutonium and plutonium-based intermetallic compounds are extremely sensitive to temperature, pressure, and chemical alloying. A celebrated example is the high-temperature $\delta$ phase plutonium, which can be…

Strongly Correlated Electrons · Physics 2024-05-15 Li Huang , Haiyan Lu

We extend our analysis of a IIB supergravity solution dual to a spatially anisotropic finite-temperature N=4 super Yang-Mills plasma. The solution is static, possesses an anisotropic horizon, and is completely regular. The full geometry can…

High Energy Physics - Theory · Physics 2011-11-10 David Mateos , Diego Trancanelli