scholarly journals OPAL Equation of State Tables

1995 ◽  
Vol 10 ◽  
pp. 331-332
Author(s):  
F.J. Rogers

The equation of state of astrophysical plasmas is, for a wide range of stars, nearly ideal with only small non-ideal Coulomb corrections. Calculating the equation of state of an ionizing plasma from a ground state ion, ideal gas model is easy, whereas, fundamental methods to include the small Coulomb corrections are difficult. Attempts to include excited bound states are also complicated by many-body effects that weaken and broaden these states. Nevertheless, the high quality of current observations, particularly seismic data, dictates that the best possible models should be used. The equation of state used in the OPAL opacity tables is based on many-body quantum statistical methods (Rogers, 1994; 1986; 1981) and is suitable for the modeling of seismic data. Extensive tables of the OPAL equation of state are now available. These tables cover the temperature range 5 × 10−3 to 1 × 108 K, the density range 10-14 to 105 g/cm3, the hydrogen mass fraction (X) range 0.0 to 0.8, and the metallicity (Z) range 0.0 to 0.04.

1994 ◽  
Vol 147 ◽  
pp. 16-42
Author(s):  
Forrest J. Rogers

AbstractThe equation of state (EOS) of astrophysical plasmas is, for a wide range of stars, nearly ideal; with only small non-ideal Coulomb corrections. Calculating the EOS of an ionizing plasma from a ground state ion, ideal gas model is easy, whereas, fundamental methods to include the small Coulomb corrections are difficult. Attempts to include excited bound states are also complicated by plasma screening and microfield phenomena that weaken and broaden these states. Nevertheless, the high quality of current observational data, particularly seismic, dictates that the best possible models should be used. The present article discusses these issues and describes how they are resolved by fundamental many-body quantum statistical methods. Particular emphasis is placed on the activity expansion method that is the basis of the OPAL opacity code. Some comparisons with standard methods are given.


2018 ◽  
Vol 843 ◽  
pp. 244-292 ◽  
Author(s):  
William A. Sirignano

Compressible flow varies from ideal-gas behaviour at high pressures where molecular interactions become important. It is widely accepted that density is well described through a cubic equation of state while enthalpy and sound speed are functions of both temperature and pressure, based on two parameters, $A$ and $B$, related to intermolecular attraction and repulsion, respectively. Assuming small variations from ideal-gas behaviour, a closed-form approximate solution is obtained that is valid over a wide range of conditions. An expansion in these molecular interaction parameters simplifies relations for flow variables, elucidating the role of molecular repulsion and attraction in variations from ideal-gas behaviour. Real-gas modifications in density, enthalpy and sound speed for a given pressure and temperature lead to variations in many basic compressible-flow configurations. Sometimes, the variations can be substantial in quantitative or qualitative terms. The new approach is applied to choked-nozzle flow, isentropic flow, nonlinear wave propagation and flow across a shock wave, all for a real gas. Modifications are obtained for allowable mass flow through a choked nozzle, nozzle thrust, sonic wave speed, Riemann invariants, Prandtl’s shock relation and the Rankine–Hugoniot relations. Forced acoustic oscillations can show substantial augmentation of pressure amplitudes when real-gas effects are taken into account. Shocks at higher temperatures and pressures can have larger pressure jumps with real-gas effects. Weak shocks decay to zero strength at sonic speed. The proposed framework can rely on any cubic equation of state and can be applied to multicomponent flows or to more complex flow configurations.


2003 ◽  
Vol 31 (3) ◽  
pp. 189-200 ◽  
Author(s):  
Jeffery D. Lewins

Many of the conventional results obtained when optimising the performance of an intercooler during compression using a perfect gas model can be obtained when the restrictions of the model are relaxed to an ideal gas. That is, we now have temperature-dependent specific heat capacities but retain the equation of state pV = RT. This note illustrates the theme.


2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.


2019 ◽  
pp. 462-471
Author(s):  
Lyudmila Shirokova

The historical polyethnicity of the Slovak society and the connected problems of the interrelations of cultures, ethics, interpersonal relations, are reflected in the works of modern Slovak prose. They are represented most clearly in the novels of middle generation writers P. Rankov, S. Lavrík, P. Krištúfek. They dwell upon the dramatical events of the 20 th century. They cover wide range problems, from the fruitful coexistence of various ethnic groups and their representatives to national contradictions and racial repressions. The artistic quality of the mentioned works, their composition, the way of narrating, the type of the main character, can be highly evaluated. For example, in a novel by P. Rankov the plot, in spite of its linearity, is a chain of episodes in the span of 30 years from the life of the main characters. It reflects not only their fates, but also the historical and political changes of the world they live in. The main female character of a S. Lavrík ’s novel narrates about everyday life and tragedies in the lives of the dwellers of a Slovak town in the Slovak Republic during the war. P. Krištúfek in his novel focuses on several decades from the life of a Slovak-Jewish family and dwellers of a Slovak provincial society with types and relations specific for this milieu.


Author(s):  
Katherine V. Whittington

Abstract The electronics supply chain is being increasingly infiltrated by non-authentic, counterfeit electronic parts, whose use poses a great risk to the integrity and quality of critical hardware. There is a wide range of counterfeit parts such as leads and body molds. The failure analyst has many tools that can be used to investigate counterfeit parts. The key is to follow an investigative path that makes sense for each scenario. External visual inspection is called for whenever the source of supply is questionable. Other methods include use of solvents, 3D measurement, X-ray fluorescence, C-mode scanning acoustic microscopy, thermal cycle testing, burn-in technique, and electrical testing. Awareness, vigilance, and effective investigations are the best defense against the threat of counterfeit parts.


2020 ◽  
Vol 1 (10(79)) ◽  
pp. 12-18
Author(s):  
G. Bubyreva

The existing legislation determines the education as "an integral and focused process of teaching and upbringing, which represents a socially important value and shall be implemented so as to meet the interests of the individual, the family, the society and the state". However, even in this part, the meaning of the notion ‘socially significant benefit is not specified and allows for a wide range of interpretation [2]. Yet the more inconcrete is the answer to the question – "who and how should determine the interests of the individual, the family and even the state?" The national doctrine of education in the Russian Federation, which determined the goals of teaching and upbringing, the ways to attain them by means of the state policy regulating the field of education, the target achievements of the development of the educational system for the period up to 2025, approved by the Decree of the Government of the Russian Federation of October 4, 2000 #751, was abrogated by the Decree of the Government of the Russian Federation of March 29, 2014 #245 [7]. The new doctrine has not been developed so far. The RAE Academician A.B. Khutorsky believes that the absence of the national doctrine of education presents a threat to national security and a violation of the right of citizens to quality education. Accordingly, the teacher has to solve the problem of achieving the harmony of interests of the individual, the family, the society and the government on their own, which, however, judging by the officially published results, is the task that exceeds the abilities of the participants of the educational process.  The particular concern about the results of the patriotic upbringing served as a basis for the legislative initiative of the RF President V. V. Putin, who introduced the project of an amendment to the Law of RF "About Education of the Russian Federation" to the State Duma in 2020, regarding the quality of patriotic upbringing [3]. Patriotism, considered by the President of RF V. V. Putin as the only possible idea to unite the nation is "THE FEELING OF LOVE OF THE MOTHERLAND" and the readiness for every sacrifice and heroic deed for the sake of the interests of your Motherland. However, the practicing educators experience shortfalls in efficient methodologies of patriotic upbringing, which should let them bring up citizens, loving their Motherland more than themselves. The article is dedicated to solution to this problem based on the Value-sense paradigm of upbringing educational dynasty of the Kurbatovs [15].


2019 ◽  
Vol 65 (1) ◽  
pp. 16-26
Author(s):  
Pavel Rumyantsev ◽  
Petr Nikiforovich ◽  
Andrey Poloznikov ◽  
Andrey Abrosimov ◽  
Vladimir Saenko ◽  
...  

Mutation BRAFV600E is highly specific for papillary thyroid carcinoma. It’s detected in 40-70% of all papillary thyroid carcinoma cases. Moreover this mutation is noticed in anaplastic carcinoma in 40-50%.This fact gives a chance to select patients and provide targeted therapy with multi-kinase inhibitors in cases of unresectable anaplastic carcinoma. The influence of BRAF V600E mutation for response to radioactive iodine therapy requires more evidence-based research. Existing methods for determining the BRAFV600E mutation have different accuracy, availability and cost. Other methodological aspects are also associated with the sample preparation of biological material, the quality of reagents, and the cross-validation of research results. In this review, on the basis of our own experience and literature data, the indications for determining the mutation of the BRAFV600E gene in clinical practice are refined, and a comprehensive comparative analysis of modern research methods has been conducted. This review is focused on a wide range of specialists of different types: oncologists, endocrinologists, radiologists, pathologists, and biologists.


In his philosophical writings, Coleridge increasingly developed his thinking about imagination, a symbolizing precursor to contemplation, to a theory of contemplation itself, which for him occurs in its purest form as a manifestation of ‘Reason’. Coleridge is a particularly challenging figure because he was a thinker in process, and something of an omnimath, a Renaissance man of the Romantic era. The dynamic quality of his thinking, the ‘dark fluxion’ pursued but ultimately ‘unfixable by thought’, and his extensive range of interests make essential an approach that is philosophical yet also multi-disciplinary. This is the first collection of essays to be written mainly by philosophers and intellectual historians on a wide range of Coleridge’s philosophical writings. With a foreword by Baroness Mary Warnock, and original essays on Coleridge and Contemplation by prominent philosophers such as Sir Roger Scruton, David E. Cooper, Michael McGhee, and Andy Hamilton, this volume provides a stimulating collection of insights and explorations into what Britain’s foremost philosopher-poet had to say about the contemplation that he considered to be the highest of the human mental powers. The essays by philosophers are supported by new developments in philosophically minded criticism from Coleridge scholars in English departments, including Jim Mays, Kathleen Wheeler, and James Engell. They approach Coleridge as an energetic yet contemplative thinker concerned with the intuition of ideas and the processes of cultivation in self and society. Other essays, from intellectual historians and theologians, clarify the historical background, and ‘religious musings’, of Coleridge’s thought regarding contemplation.


Author(s):  
Klaus Morawetz

The classical non-ideal gas shows that the two original concepts of the pressure based of the motion and the forces have eventually developed into drift and dissipation contributions. Collisions of realistic particles are nonlocal and non-instant. A collision delay characterizes the effective duration of collisions, and three displacements, describe its effective non-locality. Consequently, the scattering integral of kinetic equation is nonlocal and non-instant. The non-instant and nonlocal corrections to the scattering integral directly result in the virial corrections to the equation of state. The interaction of particles via long-range potential tails is approximated by a mean field which acts as an external field. The effect of the mean field on free particles is covered by the momentum drift. The effect of the mean field on the colliding pairs causes the momentum and the energy gains which enter the scattering integral and lead to an internal mechanism of energy conversion. The entropy production is shown and the nonequilibrium hydrodynamic equations are derived. Two concepts of quasiparticle, the spectral and the variational one, are explored with the help of the virial of forces.


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