New possibilities of applications of the Barker quasi-lattice theory. Some relations between excess functions at infinite dilution

1979 ◽  
Vol 44 (6) ◽  
pp. 1841-1851 ◽  
Author(s):  
Vladimír Dohnal ◽  
Robert Holub ◽  
Jiří Pick
Keyword(s):  
Experimental Data ◽  
Lattice Theory ◽  
Infinite Dilution ◽  
Binary Systems ◽  
Excess Enthalpy ◽  
Binary Solution ◽  
Simple Relation ◽  
Geometrical Model ◽  
The Other ◽  
Excess Functions

A relation for the limiting activity coefficient and for the partial excess enthalpy of binary solution was derived from the Barker quasi-lattice theory. On the basis of these equations we found the relations between γi##h or hiE ##h for some groups of related binary systems in an especially simple form so that is it possible to convert these quantities from one system to another without the evaluation or knowledge of adjustable energy parameters. For some predictions it is only necessary to choose a geometrical model of molecules involved in them. The relations were obtained for binary systems whose one component is formed by monotonous molecules varying in size (such as n-alkanes) and the other component is arbitrary. A very simple relation also holds for limiting activity coefficients of substances forming homologous series in two arbitrary solvents. The practical utility and accuracy of the relations obtained is demonstrated on a number of examples. The agreement with experimental data is excellent for absolute majority of the systems tested.

scholarly journals Evaluation of an empirical model used for deriving the fluidization velocity of binary mixtures of biomasses and sand

2020 ◽  
Vol 9 (9) ◽  
pp. e49996648
Author(s):  
David da Silva Vasconcelos ◽  
Sirlene Barbosa Lima ◽  
Ana Cristina Morais da Silva ◽  
José Mário Ferreira Júnior ◽  
Carlos Augusto de Moraes Pires
Keyword(s):  
Experimental Data ◽  
Statistical Model ◽  
Mass Fraction ◽  
Binary Systems ◽  
Particle Diameter ◽  
Data Representation ◽  
The Other ◽  
Experimental Planning ◽  
Fluidization Velocity ◽  
Planning Technique

In a previous study, a statistical model was developed using the experimental planning technique for evaluating the influence of its variables on fluidization velocity. In this study, we investigated the Vasconcelos-statistical model (VSM) in data representation, considering fluidization with and without segregation. The methodology used was based on the simulation of the fluidization velocity of nine binary systems, comprising sand, and eight biomasses published by six authors. In addition, the results obtained using VSM were compared with those obtained using five other models, reported by different authors, but adjusted to the experimental data of these biomasses. The result obtained by the proposed models mainly indicated a discrepancy between the experimental and calculated fluidization velocities. VSM, using only three variables (particle size, particle diameter, and biomass mass fraction), yielded results of smaller discrepancy values in all simulations (2.23–12.51%), as opposed to the other comparative models, which presented more significant numbers of variables. Thus, VSM is defined as one of the most interesting models for predicting the fluidization velocity of several biomasses.

Exzeßenthalpien und Solvatationsverhalten der Systeme LiBr/Methanol, ZnBr2/Methanol und LiBr/ZnBr2/Methanol

1982 ◽  
Vol 37 (3) ◽  
pp. 224-231
Author(s):  
M. Christahl ◽  
J. Thönnissen
Keyword(s):  
Experimental Data ◽  
Ternary System ◽  
Coordination Number ◽  
Binary Systems ◽  
Excess Enthalpy ◽  
Enthalpies Of Solution ◽  
Solvation Number ◽  
Enthalpies Of Mixing ◽  
Mathematical Approximation

Abstract For the binary systems Li Br/methanol and Zn Br 2/methanol as well as for the ternary system Li Br/Zn Br 2/methanol the integral enthalpies of mixing are experimentally determined. The mixing of Li Br and methanol is more exothermic than in the case of Zn Br 2. The excess enthalpy is largest for the ternary system. From the mathematical approximation of experimental data the differential enthalpies of solution and of dilution are obtained. In the discussion it is concluded that in diluted solutions the salts are surrounded by a strongly coordinated inner solvation sphere (coordination number N = 4) and a less coordinated outer solvation sphere (N = 6) resulting in a total solvation number of N = 10.

scholarly journals Estimation of viscosity for some silicate ternary slags

2014 ◽  
Vol 50 (2) ◽  
pp. 139-144 ◽  
Author(s):  
Q. Shu ◽  
L. Wang ◽  
K.C. Chou
Keyword(s):  
Experimental Data ◽  
General Solution ◽  
Gibbs Energy ◽  
Binary Systems ◽  
Geometrical Model ◽  
Solution Model ◽  
Mean Deviation ◽  
Model Parameters ◽  
General Solution Model ◽  
Good Agreement

A new method, combining KTH model with geometrical model (General solution model by Chou) to estimate viscosity of some ternary silicate slags, was proposed in this work. According to modified KTH model, viscous Gibbs free energy for mixing of ternary slags was estimated by employing general solution model. It was found that viscous Gibbs energy for mixing of ternary system could be calculated using solely viscous Gibbs energy for mixing of sub-binary systems. The viscosities of five ternary slags CaO-MnO-SiO2, CaO-FeO-SiO2, FeO-MnO-SiO2, CaO-MgO-SiO2 and FeO-MgO-SiO2 were estimated in the present work. A good agreement with available experimental data, with mean deviation less than 20%, was achieved. The modified KTH model has advantages with less model parameters and improved estimation ability by comparison to original KTH model.

Vapour-Liquid Equilibria and Excess Thermodynamic Properties in Binary Systems of Cyclopentanone + Chloroalkanes in View of the Disquac and Unifac Group Contribution Models Extention

2008 ◽  
Vol 59 (5) ◽  
Author(s):  
Alexandru Birhala ◽  
Dana Dragoescu ◽  
Mariana Teodorescu
Keyword(s):  
Binary Systems ◽  
Excess Enthalpy ◽  
Group Contribution ◽  
Excess Properties ◽  
Structural Effects ◽  
Liquid Equilibrium ◽  
Excess Thermodynamic Properties ◽  
Different Types ◽  
Thermodynamic Excess Properties ◽  
Thermodynamic Excess

The data available in the literature and our recent data on vapour�liquid equilibrium (VLE), excess Gibbs energy, GE, and excess enthalpy, HE, for the homologous series of cyclopentanone + chloroalkane mixtures are examined in terms of the predictive group contribution models DISQUAC and UNIFAC. In our treatment, we present also how the structural effects and different types of molecular interactions are reflected by the thermodynamic excess properties of the mentioned series mixtures.

scholarly journals Two and three pseudoscalar production in e+e− annihilation and their contributions to (g − 2)μ

2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
Wen Qin ◽  
Ling-Yun Dai ◽  
Jorge Portolés
Keyword(s):  
Experimental Data ◽  
Theoretical Prediction ◽  
Pseudoscalar Meson ◽  
Magnetic Moment ◽  
Anomalous Magnetic Moment ◽  
Vacuum Polarization ◽  
Meson Production ◽  
The Other ◽  
Joint Analysis ◽  
The Standard Model

Abstract A coherent study of e+e− annihilation into two (π+π−, K+K−) and three (π+π−π0, π+π−η) pseudoscalar meson production is carried out within the framework of resonance chiral theory in energy region E ≲ 2 GeV. The work of [L.Y. Dai, J. Portolés, and O. Shekhovtsova, Phys. Rev. D88 (2013) 056001] is revisited with the latest experimental data and a joint analysis of two pseudoscalar meson production. Hence, we evaluate the lowest order hadronic vacuum polarization contributions of those two and three pseudoscalar processes to the anomalous magnetic moment of the muon. We also estimate some higher-order additions led by the same hadronic vacuum polarization. Combined with the other contributions from the standard model, the theoretical prediction differs still by (21.6 ± 7.4) × 10−10 (2.9σ) from the experimental value.

APPLICATION OF A NEW HAMILTONIAN OF INTERACTION TO THREE-DIMENSIONAL STRUCTURES

2004 ◽  
Vol 18 (09) ◽  
pp. 1351-1368
Author(s):  
ANDREI DOLOCAN ◽  
VOICU OCTAVIAN DOLOCAN ◽  
VOICU DOLOCAN
Keyword(s):  
Experimental Data ◽  
Cohesive Energy ◽  
Noble Gases ◽  
Three Dimensional ◽  
The Other ◽  
Ionic Crystals ◽  
Coupling Constant ◽  
Good Agreement

Using a new Hamiltonian of interaction we have calculated the cohesive energy in three-dimensional structures. We have found the news dependences of this energy on the distance between the atoms. The obtained results are in a good agreement with experimental data in ionic, covalent and noble gases crystals. The coupling constant γ between the interacting field and the atoms is somewhat smaller than unity in ionic crystals and is some larger than unity in covalent and noble gases crystals. The formulae found by us are general and may be applied, also, to the other types of interactions, for example, gravitational interactions.

Electron drift caused by rf field gradient creates many plasma phenomena: An attempt to distinguish the cause and the effect

2011 ◽  
Vol 78 (2) ◽  
pp. 165-174 ◽  
Author(s):  
C. L. XAPLANTERIS ◽  
E. D. FILIPPAKI ◽  
I. S. MISTAKIDIS ◽  
L. C. XAPLANTERIS
Keyword(s):  
Experimental Data ◽  
Steady State ◽  
Low Temperature ◽  
Mathematical Models ◽  
Field Gradient ◽  
Collision Frequency ◽  
The Other ◽  
Frequency Effect ◽  
Electron Drift ◽  
Plasma Parameters

AbstractMany experimental data along with their theoretical interpretations on the rf low-temperature cylindrical plasma have been issued until today. Our Laboratory has contributed to that research by publishing results and interpretative mathematical models. With the present paper, two issues are being examined; firstly, the estimation of electron drift caused by the rf field gradient, which is the initial reason for the plasma behaviour, and secondly, many new experimental results, especially the electron-neutral collision frequency effect on the other plasma parameters and quantities. Up till now, only the plasma steady state was taken into consideration when a theoretical elaboration was carried out, regardless of the cause and the effect. This indicates the plasma's complicated and chaotic configuration and the need to simplify the problem. In the present work, a classification about the causality of the phenomena is attempted; the rf field gradient electron drift is proved to be the initial cause.

Buckling Design of Axially Compressed Cylindrical Shells Based on Energy Barrier Approach

2021 ◽  
pp. 2150165
Author(s):  
Haigui Fan ◽  
Wenguang Gu ◽  
Longhua Li ◽  
Peiqi Liu ◽  
Dapeng Hu
Keyword(s):  
Experimental Data ◽  
Energy Barrier ◽  
Thin Shell ◽  
Design Method ◽  
Lightweight Design ◽  
Cylindrical Shells ◽  
Design Criterion ◽  
The Other ◽  
Shell Structures ◽  
Buckling Loads

Buckling design of axially compressed cylindrical shells is still a challenging subject considering the high imperfection-sensitive characteristic in this kind of structure. With the development of various design methods, the energy barrier concept dealing with buckling of imperfection-sensitive cylindrical shells exhibits a promising prospect in recent years. In this study, buckling design of imperfection-sensitive cylindrical shells under axial compression based on the energy barrier approach is systematically investigated. The methodology about buckling design based on the energy barrier approach is described in detail first taking advantage of the cylindrical shells whose buckling loads have been extensively tested. Then, validation and discussion about this buckling design method have been carried out by the numerical and experimental analyses on the cylindrical shells with different geometrical and boundary imperfections. Results in this study together with the available experimental data have verified the reliability and advantage of the buckling design method based on energy barrier approach. A design criterion based on the energy barrier approach is therefore established and compared with the other criteria. Results indicate that buckling design based on energy barrier approach can be used as an efficient way in the lightweight design of thin-shell structures.

Concentration Dependence of the Surface Tension of Three and Four-Component Systems with Peculiarities in the Surface Tension Isotherms of Lateral Binary Melts

2021 ◽  
Vol 1022 ◽  
pp. 194-202
Author(s):  
R.Kh. Dadashev ◽  
R.A. Kutuev
Keyword(s):  
Experimental Data ◽  
Surface Tension ◽  
Concentration Dependence ◽  
Experimental Error ◽  
Binary Systems ◽  
Experimental Studies ◽  
Study Results ◽  
Component Systems ◽  
Minimum Depth ◽  
Surface Tension Isotherms

The experimental study results of the melts concentration dependence of the surface tension of the four-component indium-tin-lead-bismuth system and its constituent binary systems of indium-tin, indium-lead, indium-bismuth, tin-lead, tin-bismuth, lead-bismuth are presented in the paper. It is shown that the concentration dependence of the melts surface tension of the In-Sn-Pb-Bi four-component system can be predicted from the data on ST (surface tension) values of lateral binary systems. Features in the ST isotherms in the form of a minimum are observed only in the indium-tin lateral system from all lateral binaries. A distinctive feature of the detected minimum is that the minimum depth slightly exceeds the experimental error. Therefore, in addition to the fact that the area of average compositions was studied more thoroughly, we carried out the surface tension measurements by two independent methods. The experimental data obtained by both methods coincide within the experimental error and indicate the extremum availability on ST isotherms. Thus, ST experimental studies by two independent methods confirmed the presence of a flat minimum on ST isotherms of the indium-tin binary system increasing the reliability of the obtained data. The obtained outcomes and their comparison with experimental data have shown that the considered models for predicting surface properties based on data due to similar properties of lateral binary systems adequately reflect the experimental dependences. However, the prediction model based on Kohler's method of excess values describes the experimental curves more accurately.

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