Activation Volumes of Magnetic Aftereffects: Role of the Magnon Chemical Potential in Nanomagnets

2006 ◽  
Vol 42 (10) ◽  
pp. 3614-3616 ◽  
Author(s):  
L.H. Bennett ◽  
E. Della Torre ◽  
S. Rao ◽  
R.E. Watson
Keyword(s):  
Chemical Potential

Noncommutative scalar field in de Sitter space–time and pair creation process

2021 ◽  
Vol 36 (02) ◽  
pp. 2150011
Author(s):  
Nabil Mehdaoui ◽  
Lamine Khodja ◽  
Salah Haouat
Keyword(s):  
Scalar Field ◽  
Chemical Potential ◽  
De Sitter Space ◽  
Space Time ◽  
Pair Creation ◽  
De Sitter ◽  
Creation Process ◽  
Scalar Particles ◽  
Constant Electromagnetic Field

In this work, we address the process of pair creation of scalar particles in [Formula: see text] de Sitter space–time in presence of a constant electromagnetic field by applying the noncommutativity on the scalar field up to first-order in [Formula: see text]. We calculate the density of particles created in the vacuum by the mean of the Bogoliubov transformations. In contrast to a previous result, we show that noncommutativity contributes to the pair creation process. We find that the noncommutativity plays the same role of chemical potential and gives an important interest for studies at high energies.

Theoretical study of first row transitional metals effects on stabilization of verdoheme analogues

2019 ◽  
Vol 23 (10) ◽  
pp. 1100-1109
Author(s):  
Afsaneh Taghizadeh ◽  
Maryam Daghighi Asli ◽  
Parisa Rajabali Jamaat
Keyword(s):  
Chemical Potential ◽  
Dft Method ◽  
Basis Set ◽  
Orbital Energy ◽  
Central Metal ◽  
Transitional Metals ◽  
Solvent Phase ◽  
Energy Formula ◽  
Homo And Lumo

Heme catabolism is an important physiological process that converts heme to biliverdin in the presence of heme oxygenase which has an essential role in destroying unwanted heme. Verdohemes, the green iron (II) complexes of the 5-oxaporphyrin macrocycle are produced by oxidative destruction of heme. The main goal of this study is clarification of the central metal effect on stabilization of metal 5-oxaporphyrin molecules. To investigate the role of central metal on geometric and electronic properties of five coordinated verdoheme analogues, the first row transitional metals, including Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zn, as the central metal of five-coordinated metal 5-oxaporphyrins were systematically calculated without any symmetry constraint by using the B3LYP as DFT method and the 6-31G basis set in gas and solvent phases. According to the results, the stabilization energy of metal 5-oxaporphyrins increases with atomic mass in the solvent phase more than in the gas phase. By reviewing the properties such as the computed frontier orbital energy, HOMO and LUMO gap energy [Formula: see text], hardness [Formula: see text], chemical potential [Formula: see text], softness (s) and electrophilicity [Formula: see text], the pharmaceutical use of this compound can be discussed.

THE ROLE OF ANTIKAON CONDENSATES IN THE EQUATION OF STATE OF NEUTRON STARS

2010 ◽  
Vol 19 (08n10) ◽  
pp. 1545-1548 ◽  
Author(s):  
F. FERNÁNDEZ ◽  
A. MESQUITA ◽  
M. RAZEIRA ◽  
C. A. Z. VASCONCELLOS
Keyword(s):  
Neutron Stars ◽  
Electric Charge ◽  
Chemical Potential ◽  
Mean Field ◽  
Field Approximation ◽  
Mean Field Approximation ◽  
Charge Neutrality ◽  
The Mean ◽  
Nucleon Matter

We study the consequences of the presence of a negative electric charge condensate of antikaons in neutron stars using an effective model with derivative couplings. In our formalism, nucleons interact through the exchange of σ, ω and ϱ mesons, in the presence of electrons and muons, to accomplish electric charge neutrality and beta equilibrium. The phase transition to the antikaon condensate was implemented through the Gibbs conditions combined with the mean-field approximation, giving rise to a mixed phase of coexistence between nucleon matter and the antikaon condensate. Assuming neutrino-free matter, we observe a rapid decrease of the electron chemical potential produced by the gradual substitution of electrons by kaons to accomplish electric charge neutrality. The exotic composition of matter in neutron star including antikaon condensation and nucleons can yield a maximum mass of about M ns ~ 1.76 M ⊙.

Role of chemical potential in relaxation of faceted crystal structure

2014 ◽  
Vol 89 (6) ◽  
Author(s):  
Joshua P. Schneider ◽  
Kanna Nakamura ◽  
Dionisios Margetis
Keyword(s):  
Crystal Structure ◽  
Chemical Potential

Role of Chemical Potential in Flake Shape and Edge Properties of Monolayer MoS2

2015 ◽  
Vol 119 (8) ◽  
pp. 4294-4301 ◽  
Author(s):  
Dan Cao ◽  
Tao Shen ◽  
Pei Liang ◽  
Xiaoshuang Chen ◽  
Haibo Shu
Keyword(s):  
Chemical Potential ◽  
Monolayer Mos2

scholarly journals The key role of µH2O gradients in deciphering microstructures and mineral assemblages of mylonites: examples from the Calabria polymetamorphic terrane

2021 ◽  
Author(s):  
Fabrizio Tursi
Keyword(s):  
Chemical Potential ◽  
Shear Zones ◽  
Chemical Potentials ◽  
Ductile Shear Zones ◽  
Mineral Assemblages ◽  
Potential Gradients ◽  
Ductile Shear ◽  
Chemical Potential Gradients

AbstractA careful petrologic analysis of mylonites’ mineral assemblages is crucial for a thorough comprehension of the rheologic behaviour of ductile shear zones active during an orogenesis. In this view, understanding the way new minerals form in rocks sheared in a ductile manner and why relict porphyroblasts are preserved in zones where mineral reactions are generally supposed to be deformation-assisted, is essential. To this goal, the role of chemical potential gradients, particularly that of H2O (µH2O), was examined here through phase equilibrium modelling of syn-kinematic mineral assemblages developed in three distinct mylonites from the Calabria polymetamorphic terrane. Results revealed that gradients in chemical potentials have effects on the mineral assemblages of the studied mylonites, and that new syn-kinematic minerals formed in higher-µH2O conditions than the surroundings. In each case study, the banded fabric of the mylonites is related to the fluid availability in the system, with the fluid that was internally generated by the breakdown of OH-bearing minerals. The gradients in µH2O favoured the origin of bands enriched in hydrated minerals alternated with bands where anhydrous minerals were preserved even during exhumation. Thermodynamic modelling highlights that during the prograde stage of metamorphism, high-µH2O was necessary to form new minerals while relict, anhydrous porphyroblasts remained stable in condition of low-µH2O even during exhumation. Hence, the approach used in this contribution is an in-depth investigation of the fluid-present/-deficient conditions that affected mylonites during their activity, and provides a more robust interpretation of their microstructures, finally helping to explain the rheologic behaviour of ductile shear zones.

scholarly journals Polarization in HIC: comparison of methods

2019 ◽  
Vol 204 ◽  
pp. 05003
Author(s):  
Georgy Prokhorov ◽  
Oleg Teryaev ◽  
Valentin Zakharov
Keyword(s):  
Angular Velocity ◽  
Wigner Function ◽  
Chemical Potential ◽  
Axial Current ◽  
Comparison Of Methods ◽  
Boundary Temperature ◽  
Chemical Potentials

Based on the Wigner function for an medium with thermal vorticity, an exact non-perturbative formula for axial current was obtained. It is confirmed that the Chiral Vortical Effect results from the Wigner function. It is shown that the angular velocity and acceleration play the role of new chemical potentials, which is expressed in the appearance of combination $$\mu \pm \,(\Omega \pm i\left| a \right|)/2$$. It is shown that acceleration enters in the form of imaginary chemical potential and the consequences of this fact are investigated. An expression for the boundary temperature for a medium of fermions, which simultaneously has acceleration and rotation, is derived. This temperature in the particular case coincides with the temperature of Unruh.

Roles of colloidal molecules in Starling's hypothesis and in returning interstitial fluid to the vasa recta

1995 ◽  
Vol 268 (5) ◽  
pp. H2133-H2144 ◽  
Author(s):  
H. T. Hammel
Keyword(s):  
Aqueous Solution ◽  
Interstitial Fluid ◽  
Chemical Potential ◽  
Pure Water ◽  
External Pressure ◽  
Capillary Endothelium ◽  
Free Fluid ◽  
Vasa Recta ◽  
Simple Question

To begin to understand the role of colloidal molecules, a simple question requires an answer: How do the solutes alter water in an aqueous solution? Hulett's answer deserves attention, namely, the water in the solution at temperature and external pressure applied to solution (T,pe1) is altered in the same way that pure water is altered by reducing the pressure applied to it by the osmotic pressure of the water at a free surface of the solution. It is nonsense to relate the lower chemical potential of water in a solution to a lower fugacity or to a lower activity of the water in the solution, since these terms have no physical meaning. It is also incorrect to attribute the lower chemical potential of the water to a lower concentration of water in the solution. Both claims are derived from the teachings of G. N. Lewis and are erroneous. Textbook accounts of the flux of fluid to and from capillaries in the kidney and other tissues are inadequate, if not in error, as they are based on these bogus claims. An understanding of the process by which colloidal proteins in plasma affect the flux of nearly protein-free fluid across the capillary endothelium must start with insights derived from the teachings of G. Hulett and H. Dixon. The main points are 1) colloidal molecules can exert a pressure against a membrane that reflects them and, thereby, displace a distensible membrane; 2) they can alter the internal tension of the fluid through which they diffuse when there is a concentration gradient of the molecules; and 3) only by these means can they influence the flux of plasma fluid across the capillary endothelium. However, the process is complex, since both the hydrostatic pressure and protein concentrations of fluids inside and outside the capillary vary with both position and time as plasma flows through the capillary.

scholarly journals The chiral phase transition and the role of vacuum fluctuations

2016 ◽  
Vol 31 (07) ◽  
pp. 1650025 ◽  
Author(s):  
Rashid Khan ◽  
Jens O. Andersen ◽  
Lars T. Kyllingstad ◽  
Majid Khan
Keyword(s):  
Phase Transition ◽  
Effective Potential ◽  
Chemical Potential ◽  
Chiral Limit ◽  
Vacuum Fluctuations ◽  
Physical Point ◽  
Chiral Phase ◽  
First Order ◽  
First Order Transition

We apply optimized perturbation theory to the quark–meson model at finite temperature [Formula: see text] and quark chemical potential [Formula: see text]. The effective potential is calculated to one loop both in the chiral limit and at the physical point and used to study the chiral dynamics of two-flavor QCD. The critical temperature and the order of the phase transition depend heavily on whether or not one includes the bosonic and fermionic vacuum fluctuations in the effective potential. A full one-loop calculation in the chiral limit predicts a first-order transition for all values of [Formula: see text]. At the physical point, one finds a crossover in the whole [Formula: see text]–[Formula: see text] plane.

scholarly journals Effect of Constituent Units, Type of Interflavan Bond, and Conformation on the Antioxidant Properties of Procyanidin Dimers: A Computational Outlook

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Ana María Mendoza-Wilson ◽  
René Renato Balandrán-Quintana
Keyword(s):  
Density Functional ◽  
Chemical Potential ◽  
Antioxidant Properties ◽  
Computational Method ◽  
Antioxidant Ability ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Fukui Indices ◽  
Homo Lumo

Procyanidin (PC) dimers are powerful antioxidants, abundant in plant tissues, and also bioavailable. However, the role of the molecular structure of PCs on their antioxidant properties is still a controversial and not fully understood issue that needs to be addressed in a more specific way. The objective of this study was to analyze the effect of the constituent units, type of interflavan bond, and conformation on the antioxidant properties of PC dimers including PB3, PB4, PB5, PB6, PB7, and PB8, using the density functional theory (DFT) computational method. The analysis was performed in function of parameters that allow determining the ability of the molecules to transfer or to capture electrons, among which the chemical potential, bond dissociation enthalpy (BDE), gap energy, Fukui indices, and charge distribution of HOMO-LUMO orbitals. The factors that showed the most notable effects on the antioxidant properties of the PC dimers were the type of interflavan bond and the conformation. The antioxidant ability of the dimers PB3 and PB4 containing the interflavan bond C4–C8, in their Compact conformation, was very similar to each other but greater than those of dimers PB5, PB6, PB7, and PB8 containing the C4–C6 interflavan bond. PB8 showed the lowest antioxidant ability.

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