1,252 research outputs found
Grand canonical partition functions for multi level para Fermi systems of any order
A general formula for the grand canonical partition function for a para Fermi
system of any order and of any number of levels is derived.Comment: 9 pages, latex, no figure
Probing the role of Nd3+ ions in the weak multiferroic character of NdMn2O5 by optical spectroscopies
Raman and infrared spectroscopies are used as local probes to study the
dynamics of the Nd-O bonds in the weakly multiferroic NdMn2O5 system. The
temperature dependence of selected Raman excitations reveals the splitting of
the Nd-O bonds in NdMn2O5. The Nd3+ ion crystal field (CF) excitations in
NdMn2O5 single crystals are studied by infrared transmission as a function of
temperature, in the 1800-8000 cm-1 range, and under an applied magnetic field
up to 11 T. The frequencies of all 4Ij crystal-field levels of Nd3+ are
determined. We find that the degeneracy of the ground-state Kramers doublet is
lifted ({\Delta}0 ~7.5 cm-1) due to the Nd3+-Mn3+ interaction in the
ferroelectric phase, below TC ~ 28 K. The Nd3+ magnetic moment mNd(T) and its
contribution to the magnetic susceptibility and the specific heat are evaluated
from {\Delta}0(T) indicating that the Nd3+ ions are involved in the magnetic
and the ferroelectric ordering observed below ~ 28 K. The Zeeman splitting of
the excited crystal field levels of the Nd3+ ions at low temperature is also
analyzed.Comment: This paper is accepted for publication as a Regular Article in
Physical Review
Special issue on 'Recent advances in Population Balance Modeling'
Population Balance Modeling (PBM) is a powerful modeling framework that allows the prediction of the dynamics of distributed properties of a population of individuals at the mesoscale [...
Perspectives on Resource Recovery from Bio-Based Production Processes: From Concept to Implementation
Recovering valuable compounds from waste streams of bio-based production processes is in line with the circular economy paradigm, and is achievable by implementing “simple-to-use” and well-established process separation technologies. Such solutions are acceptable from industrial, economic and environmental points of view, implying relatively easy future implementation on pilot- and full-scale levels in the bio-based industry. Reviewing such technologies is therefore the focus here. Considerations about technology readiness level (TRL) and Net Present Value (NPV) are included in the review, since TRL and NPV contribute significantly to the techno-economic evaluation of future and promising process solutions. Based on the present review, a qualitative guideline for resource recovery from bio-based production processes is proposed. Finally, future approaches and perspectives toward identification and implementation of suitable resource recovery units for bio-based production processes are discussed
Casimir Effect for Spherical Shell in de Sitter Space
The Casimir stress on a spherical shell in de Sitter background for massless
scalar field satisfying Dirichlet boundary conditions on the shell is
calculated. The metric is written in conformally flat form. Although the metric
is time dependent no particles are created. The Casimir stress is calculated
for inside and outside of the shell with different backgrounds corresponding to
different cosmological constants. The detail dynamics of the bubble depends on
different parameter of the model. Specifically, bubbles with true vacuum inside
expand if the difference in the vacuum energies is small, otherwise they
collapse.Comment: 9 pages, submitted to Class. Quantum Gra
Noncommutative gravity: fuzzy sphere and others
Gravity on noncommutative analogues of compact spaces can give a finite mode
truncation of ordinary commutative gravity. We obtain the actions for gravity
on the noncommutative two-sphere and on the noncommutative in
terms of finite dimensional -matrices. The commutative large
limit is also discussed.Comment: LaTeX, 13 pages, section on CP^2 added + minor change
A shortcut approach for decision-making and operational analysis of an integrated end-to-end continuous pharmaceutical process [Abstract]
A shortcut approach for decision-making and operational analysis of an integrated end-to-end continuous pharmaceutical process [Abstract
The Great Escape: Viral Strategies to Counter BST-2/Tetherin
The interferon-induced BST-2 protein has the unique ability to restrict the egress of HIV-1, Kaposi's sarcoma–associated herpesvirus (KSHV), Ebola virus, and other enveloped viruses. The observation that virions remain attached to the surface of BST-2-expressing cells led to the renaming of BST-2 as “tetherin”. However, viral proteins such as HIV-1 Vpu, simian immunodeficiency virus Nef, and KSHV K5 counteract BST-2, thereby allowing mature virions to readily escape from infected cells. Since the anti-viral function of BST-2 was discovered, there has been an explosion of research into several aspects of this intriguing interplay between host and virus. This review focuses on recent work addressing the molecular mechanisms involved in BST-2 restriction of viral egress and the species-specific countermeasures employed by various viruses
Casimir stress on parallel plates in de Sitter space
The Casimir stress on two parallel plates in de Sitter background for
massless scalar field satisfying Robin boundary conditions on the plates is
calculated. The metric is written in conformally flat form to make maximum use
of the Minkowski space calculations. Different cosmological constants are
assumed for the space between and outside of the plates to have general results
applicable to the case of domain wall formations in the early universe.Comment: 6 page
Experiment for Testing Special Relativity Theory
An experiment aimed at testing special relativity via a comparison of the
velocity of a non matter particle (annihilation photon) with the velocity of
the matter particle (Compton electron) produced by the second annihilation
photon from the decay Na-22(beta^+)Ne-22 is proposed.Comment: 7 pages, 1 figure, Report on the Conference of Nuclear Physics
Division of Russian Academy of Science "Physics of Fundamental Interactions",
ITEP, Moscow, November 26-30, 200
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