scholarly journals Electrodynamics of Pulsar Magnetospheres

2004 ◽  
Vol 218 ◽  
pp. 357-364 ◽  
Author(s):  
Anatoly Spitkovsky
Keyword(s):  
First Principles ◽  
Recent Progress ◽  
Global Structure ◽  
Theoretical Understanding

I review the theoretical understanding of the global structure of pulsar magnetospheres concentrating on recent progress in force-free electrodynamics and first-principles simulations of magnetospheres.

scholarly journals Description of the Fission Process: Nuclear Models for Fission Dynamics

2020 ◽  
Vol 242 ◽  
pp. 03005
Author(s):  
M. Verriere ◽  
M.R. Mumpower ◽  
T. Kawano ◽  
N. Schunck
Keyword(s):  
National Security ◽  
Heavy Nucleus ◽  
First Principles ◽  
Energy Generation ◽  
Nuclear Fission ◽  
Theoretical Understanding ◽  
Fission Process ◽  
New Approaches ◽  
Nuclear Models ◽  
The Universe

Nuclear fission is the splitting of a heavy nucleus into two or more fragments, a process that releases a substantial amount of energy. It is ubiquitous in modern applications, critical for national security, energy generation and reactor safeguards. Fission also plays an important role in understanding the astrophysical formation of elements in the universe. Eighty years after the discovery of the fission process, its theoretical understanding from first principles remains a great challenge. In this paper, we present promising new approaches to make more accurate predictions of fission observables.

scholarly journals Ag3PO4Semiconductor Photocatalyst: Possibilities and Challenges

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Gui-Fang Huang ◽  
Zhi-Li Ma ◽  
Wei-Qing Huang ◽  
Yong Tian ◽  
Chao Jiao ◽  
...  
Keyword(s):  
Recent Progress ◽  
Photocatalytic Performance ◽  
Catalytic Performance ◽  
Future Research ◽  
Fuel Production ◽  
Theoretical Understanding ◽  
Research Activities ◽  
Composite Photocatalysts ◽  
The Stability ◽  
Exposed Facets

Ag3PO4as a photocatalyst has attracted enormous attention in recent years due to its great potential in harvesting solar energy for environmental purification and fuel production. The photocatalytic performance of Ag3PO4strongly depends on its morphology, exposed facets, and particle size. The effects of morphology and orientation of Ag3PO4on the catalytic performance and the efforts on the stability improvement of Ag3PO4are reviewed here. This paper also discusses the current theoretical understanding of photocatalytic mechanism of Ag3PO4, together with the recent progress towards developing Ag3PO4composite photocatalysts. The crucial issues that should be addressed in future research activities are finally highlighted.

scholarly journals Origin of Local Structures of U-Co Melts: A First-Principles Study

2022 ◽  
Vol 8 ◽  
Author(s):  
Huanqing Zhang ◽  
Honggang Sun ◽  
Qiutong Li ◽  
Li Wang
Keyword(s):  
First Principles ◽  
Distribution Functions ◽  
Chemical Effect ◽  
First Principle ◽  
Dual Roles ◽  
Theoretical Understanding ◽  
Local Structures ◽  
Solvent Model ◽  
Pair Distribution Functions ◽  
Bonding Characteristics

The local structures of U-Co melts have been studied by first-principle calculations. Two sub-peaks are observed in the first peaks of U-U pair distribution functions. The Voronoi polyhedral analyses also show two separate core-shell U-U distances. Therefore, the calculated results propose that U atoms will play dual roles, “chemical” and “topological”, in the local structures of U-Co melts. In addition, the chemical effect of U atoms will be strengthened when containing more U atoms. The interaction of Co and U atoms is slightly affected by the compositions. The Co-centered clusters are mostly prism-like or antiprism-like polyhedral, which can be predicted by the solute-solvent model. The distribution of the coordinated numbers of Co atoms is much narrower than that of U atoms, showing relatively stable Co-centered clusters. The chemical and topological roles of U atoms are intuitively observed in the electron density of U-Co melts, which presents both metallic and covalent bonding characteristics for U-U bonds. In the end, we conclude that the partial localization of U 5f-electron is responsible for the dual roles of U atoms. The present results provide a theoretical understanding of the origin of the local structures of U-Co melts.

scholarly journals Advances in quantum light emission from 2D materials

Nanophotonics ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 2017-2032 ◽  
Author(s):  
Chitraleema Chakraborty ◽  
Nick Vamivakas ◽  
Dirk Englund
Keyword(s):  
Optical Properties ◽  
Binding Energy ◽  
Momentum Space ◽  
Recent Progress ◽  
Light Emission ◽  
2D Materials ◽  
Two Dimensional ◽  
Theoretical Understanding ◽  
Practical Applications ◽  
Spin Properties

AbstractTwo-dimensional (2D) materials are being actively researched due to their exotic electronic and optical properties, including a layer-dependent bandgap, a strong exciton binding energy, and a direct optical access to electron valley index in momentum space. Recently, it was discovered that 2D materials with bandgaps could host quantum emitters with exceptional brightness, spectral tunability, and, in some cases, also spin properties. This review considers the recent progress in the experimental and theoretical understanding of these localized defect-like emitters in a variety of 2D materials as well as the future advantages and challenges on the path toward practical applications.

scholarly journals FROM COMPLEX TO STOCHASTIC POTENTIAL: HEAVY QUARKONIA IN THE QUARK–GLUON PLASMA

2013 ◽  
Vol 28 (08) ◽  
pp. 1330005 ◽  
Author(s):  
ALEXANDER ROTHKOPF
Keyword(s):  
Quark Gluon Plasma ◽  
First Principles ◽  
Bound States ◽  
Recent Progress ◽  
Open Quantum Systems ◽  
Gluon Plasma ◽  
Quantum Systems ◽  
Heavy Quarkonium ◽  
General Complex

The in-medium physics of heavy quarkonium is an ideal proving ground for our ability to connect knowledge about the fundamental laws of physics to phenomenological predictions. One possible route to take is to attempt a description of heavy quark bound states at finite temperature through a Schrödinger equation with an instantaneous potential. Here we review recent progress in devising a comprehensive approach to define such a potential from first principles QCD and extract its, in general complex, values from non-perturbative lattice QCD simulations. Based on the theory of open quantum systems we will show how to interpret the role of the imaginary part in terms of spatial decoherence by introducing the concept of a stochastic potential. Shortcomings as well as possible paths for improvement are discussed.

Flavor constraints on new physics

2014 ◽  
Vol 29 (22) ◽  
pp. 1430021 ◽  
Author(s):  
Jernej F. Kamenik
Keyword(s):  
Recent Progress ◽  
New Physics ◽  
Hierarchy Problem ◽  
Theoretical Understanding ◽  
Direct Production ◽  
Scale Theory ◽  
Null Results ◽  
Flavor Changing ◽  
The Standard Model ◽  
New Phenomena

We review the recent progress in our theoretical understanding of flavor-changing processes. The overall excellent agreement with the corresponding measurements allows to derive severe constraints on possible extensions of the Standard Model (SM). The important interplay between flavor, electroweak (EW) and Higgs boson probes of new phenomena is emphasized. Once the EW hierarchy problem is confronted with null results from searches for direct production of new particles at the LHC, a case can be made against purely flavor trivial new physics (NP) at the TeV scale. Theory implications of the few open experimental flavor puzzles are also briefly discussed.

First-principles study on the effects of V, Nb, Cd, Ag, Ge and Sb doped in Al2CuMg phase of Al–Zn–Mg–Cu alloy

2021 ◽  
pp. 2150478
Author(s):  
Bingkang Li ◽  
Junkai Wang ◽  
Chuan-Hui Zhang
Keyword(s):  
First Principles ◽  
Performance Optimization ◽  
Density Functional ◽  
Covalent Bond ◽  
Mg Alloys ◽  
Partial Density ◽  
Theoretical Understanding ◽  
Cu Alloy ◽  
Sb Doping ◽  
And Performance

The [Formula: see text] phase (Al2CuMg) is an important strengthening phase for the Al–Zn–Cu–Mg alloys, which are widely used in the aerospace and transportation industries. First-principles calculations based on the density functional theory were used to investigate the effects of doping V, Nb, Cd, Ag, Ge and Sb elements on the [Formula: see text] phase. The results demonstrate that Ag atom can spontaneously dope into the [Formula: see text] phase. Ge and Sb doping can improve the toughness and plasticity of the [Formula: see text] phase. And doping Ge, V or Nb can reduce the anisotropy of the Al2CuMg phase. The hardness of the Nb, V, Cd and Ag doped structures become larger than that of the pristine structure. The results of orbital hybridization in the partial density of states (PDOS) and the distribution in electron density difference (EDD) confirmed that the effect of doping elements and Al atoms has the greatest impact on the performance of the system, and the strength of the covalent bond of the system affects the main aspects of brittleness. This study provides a better theoretical understanding of the doped [Formula: see text] phase, providing guidance for improved composition design and performance optimization of Al–Zn–Cu–Mg alloys.

Sign in / Sign up

Export Citation Format

Share Document