scholarly journals Thermochemical properties of liquid alloys along xCu/xSb= 0.2/08 section of the ternary Cu-Sb-Ce system

2017 ◽  
Vol 5 (2) ◽  
pp. 24-29 ◽  
Author(s):  
Natalia Kotova ◽  
Michael Ivanov ◽  
Natalia Usenko
Keyword(s):  
Experimental Data ◽  
High Temperature ◽  
Cross Section ◽  
Analytical Method ◽  
Composition Dependence ◽  
Liquid Alloys ◽  
Thermochemical Properties ◽  
Enthalpies Of Mixing ◽  
The Cross ◽  
Toop Model

The enthalpies of mixing of liquid alloys of the ternary Cu–Sb–Ce system were studied by high-temperature calorimetry along the cross-section = 0.2/0.8. The composition dependence of these values were modelled using four "geometric" models and also the analytical method of Redlich–Kister–Muggianu. A comparison of the experimental data for the cross section = 0.2/0.8 and simulated values of the enthalpies of mixing showed that the most suitable for describing the properties of liquid alloys of ternary Cu–Sb–Ce system is the Toop model.

SETTING A DIAGRAM APPROACH TO CALCULATING VIBRATED, CENTRIFUGED AND VIBROCENTRIFUGED REINFORCED CONCRETE COLUMNS WITH A VARIATROPIC STRUCTURE

2020 ◽  
pp. 22-34
Author(s):  
Л. Р. Маилян ◽  
С. А. Стельмах ◽  
Е. М. Щербань ◽  
М. П. Нажуев
Keyword(s):  
Experimental Data ◽  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Cross Section ◽  
Concrete Columns ◽  
Reinforced Concrete Columns ◽  
The Cross ◽  
Concrete Elements ◽  
Diagram Approach

Состояние проблемы. Железобетонные элементы изготавливаются, как правило, по трем основным технологиям - вибрированием, центрифугированием и виброцентрифугированием. Однако все основные расчетные зависимости для определения их несущей способности выведены, исходя из основного постулата - постоянства и равенства характеристик бетона по сечению, что реализуется лишь в вибрированных колоннах. Результаты. В рамках диаграммного подхода предложены итерационный, приближенный и упрощенный способы расчета несущей способности железобетонных вибрированных, центрифугированных и виброцентрифугированных колонн. Выводы. Расчет по диаграммному подходу показал существенно более подходящую сходимость с опытными данными, чем расчет по методике норм, а также дал лучшие результаты при использовании дифференциальных характеристик бетона, чем при использовании интегральных и, тем более, нормативных характеристик бетона. Statement of the problem. Reinforced concrete elements are typically manufactured according to three basic technologies - vibration, centrifugation and vibrocentrifugation. However, all the basic calculated dependencies for determining their bearing capacity were derived using the main postulate, i.e., the constancy and equality of the characteristics of concrete over the cross section, which is implemented only in vibrated columns. Results. Within the framework of the diagrammatic approach, iterative, approximate and simplified methods of calculating the bearing capacity of reinforced concrete vibrated, centrifuged and vibrocentrifuged columns are proposed. Conclusions. The calculation according to the diagrammatic approach showed a significantly better convergence with the experimental data than that using the method of norms, and also performs better when using differential characteristics of concrete than when employing integral and particularly standard characteristics of concrete.

An Analytical Method of Analyzing the Heat Conduction for the Unequal Cross-Section Straight Fin

2013 ◽  
Vol 365-366 ◽  
pp. 1211-1216
Author(s):  
Fan Zhang ◽  
Peng Yun Song
Keyword(s):  
Heat Conduction ◽  
Cross Section ◽  
Analytical Method ◽  
Thermal Analyses ◽  
Cross Sectional ◽  
Cross Section Area ◽  
Section Area ◽  
Calculation Results ◽  
The Cross ◽  
Analytical Expressions

The cross-section area of straight fin is often considered to be equal in the thermal analyses of straight fin, but sometimes it is unequalin actual situation. Taking a straight fin with two unequal cross-sectional areas as an example,an analytical method of heat conduction for unequal section straight fin is presented. The analytical expressions of temperature field and heat dissipating capacity about the fin,which has a smaller cross-section area near the fin base and a larger one, is obtained respectively. The calculation results of the unequal cross-section are fully consistent with the equal area one, so the method is proved right. The results show that the larger the cross section areanear the base,the better is the heat transfer, and the temperature at the base with larger cross-section area is lower than that with smaller cross-section area when the amount of heat is fixed.

The inner shell ionization of atoms by electron impact

1940 ◽  
Vol 36 (1) ◽  
pp. 43-52 ◽  
Author(s):  
E. H. S. Burhop ◽  
H. S. W. Massey
Keyword(s):  
Experimental Data ◽  
Electron Impact ◽  
Cross Section ◽  
Nickel Silver ◽  
Inner Shell Ionization ◽  
Good For ◽  
The Cross ◽  
Shell Ionization ◽  
Good Agreement

Calculations have been made of the cross-section for ionization of the inner shells of atoms by electron impact in the cases of the K-shells of nickel, silver, mercury and of the three L-shells of silver and mercury.The agreement with experiment is reasonably good for the K-shell ionization, but only fair in the case of the rather meagre experimental data available for the L-shell. The values obtained for the relative ionization in the K- and L-shells are in good agreement with those to be expected from experiment.

scholarly journals CONSOLIDATION ZONES FEATURES FORMATION OF A GROUND AROUND SQUARE SHAPED PILES

2018 ◽  
Vol 1 (50) ◽  
pp. 167-173
Author(s):  
O. V. Malyshev
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Analytical Method ◽  
Lateral Surface ◽  
Analytical Methods ◽  
Rational Design ◽  
Initial State ◽  
Compaction Zone ◽  
Analytical Expressions ◽  
Efficiency And Reliability

Necessity to resolve the problem of concerning the analytical dimensions definition and constructing forms of compacted zones of ground around the lateral surface of square cross section pile in normal to pile axis direction are shown in this article. Various analytical methods of ground compacted zones radius determination around cylindrical elements driven into the ground considering its initial state were analyzed. Graph-analytical method of ground compaction zones construction around square cross-section piles was developed. Efficiency of the developed methodology and analytical expressions using possibility to determine the radius of compaction zone of a ground around the driven or jacked-in elements is confirmed by comparing obtained solutions with the experimental data. The developed methodology allows increasing the efficiency and reliability of piles and pile foundations use due to their rational design.

scholarly journals Numerical simulation of the transverse flow over spans of girder bridges

2018 ◽  
Vol 18 (4) ◽  
pp. 362-378
Author(s):  
Yu. A. Gosteev ◽  
A. D. Obukhovskiy ◽  
S. D. Salenko
Keyword(s):  
Experimental Data ◽  
Numerical Simulation ◽  
Cross Section ◽  
Cross Sections ◽  
Aerodynamic Characteristics ◽  
Transverse Flow ◽  
Single Beam ◽  
Weighted Estimates ◽  
Girder Bridges ◽  
The Cross

Introduction. The technique of numerical modeling of the transverse flow over span structures of bridges on the basis of the two-dimensional URANS (Unsteady Reynolds-averaged Navier-Stokes) approach used in the modern methods and software packages for computational fluid dynamics is verified. The work objective was debugging and experimental substantiation of this technique with the use of the database on the aerodynamic characteristics of the cross-sections of span structures of girder bridges of standard shapes pre-developed by the authors.Materials and Methods. A numerical simulation of the transverse flow of low-turbulent (smooth) and turbulent air flows around the bridge structures in a range of practically interesting attack angles is carried out. SST  k − ω turbulence model was used as the closing one. The technique was preliminarily tested on the check problem for the flow of the rectangular crosssection beams. Calculations were carried out using the licensed ANSYS software.Research Results. The calculated dependences on the attack angle of the aerodynamic coefficients of forces (drag and lift) and the moment of the cross sections of the girder bridges of standard shapes are obtained. These data refer to the span structures at the construction phase (without deck and parapets, without parapets) and operation phase, under the conditions of model smooth and turbulent incoming flow. The latter allows us to outline the boundaries for more weighted estimates of the aerodynamic characteristics of thegirder bridges in a real wind current. The best agreement with the experimental data was obtained from the drag of the cross-section. The magnitude of the lifting force is more sensitive to the presence and extent of the separation regions, so its numerical determination is less accurate. The reproduction of the angle-of-attack effect on the aerodynamic moment of the cross-section is the most challenging for the majority of configurations.Discussion and Conclusions. Comparison of the calculated and experimental data indicates the applicability of the URANS approach to the operational prediction of the aerodynamic characteristics of the single-beam span structures. In the case of multi-beam span structures, where the aerodynamic interference between separate girders plays an important role, the URANS approach must apparently give way to more accurate eddy-resolving methods. The results obtained can be used in the aerodynamic analysis of structures and in practice of the relevant design organizations in the field of transport construction.

scholarly journals Study of the Production Cross-Sections of the Neutron-rich 184Ta and 186Ta

2021 ◽  
Vol 9 (1) ◽  
pp. 25-29
Author(s):  
Susshma Nagarajan ◽  
Deepa Seetharaman ◽  
Gowrishankar Ramadurai
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Cross Section ◽  
Cross Sections ◽  
Good Yield ◽  
Production Cross ◽  
Effective Synthesis ◽  
The Cross

Synthesizing nuclei through reactions that produce a reasonable yield is important for the experimental study of neutron-rich nuclei. In this study, the cross-section values of 184Ta and 186Ta nuclei in various experiments were reviewed and analysed. The experimental data of (n, p), (p, x) and (n, α) reactions were compared to identify the best reaction to produce these nuclei for further study. Our study shows that (n, p) reactions on natural Tungsten targets are the most feasible reactions with a good yield of the neutron-rich Tantalum isotopes. New reactions have been proposed for the effective synthesis of 184Ta and 186Ta using tritium beams on Hafnium targets. The cross-section values of the proposed reactions were calculated by PACE4 software simulations.

scholarly journals A comprehensive analysis of differential cross sections and analyzing powers in the proton–deuteron break-up channel at 135 MeV

2021 ◽  
Vol 57 (2) ◽  
Author(s):  
H. Tavakoli-Zaniani ◽  
M. Eslami-Kalantari ◽  
H. R. Amir-Ahmadi ◽  
M. T. Bayat ◽  
A. Deltuva ◽  
...  
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Cross Sections ◽  
Theoretical Calculations ◽  
Nucleon Force ◽  
Satisfactory Description ◽  
Analyzing Powers ◽  
Global Comparison ◽  
Break Up ◽  
The Cross

AbstractA selection of measured cross sections and vector analyzing powers, $$A_{x}$$ A x and $$A_{y}$$ A y , are presented for the $$\vec {p}{d}$$ p → d break-up reaction. The data are taken with a polarized proton beam with a kinetic energy of 135 MeV using the Big Instrument for Nuclear-polarization Analysis (BINA) at KVI, the Netherlands. With this setup, $$A_{x}$$ A x is extracted for the first time for a large range of energies as well as polar and azimuthal angles of the two outgoing protons. For most of the configurations, the results at small and large relative azimuthal angles differ in behavior when comparing experimental data with the theoretical calculations. We also performed a more global comparison of our data with theoretical calculations. The cross-section results show huge values of $$\chi ^{2}$$ χ 2 /d.o.f.. The absolute values of $$\chi ^{2}$$ χ 2 /d.o.f. for the components of vector analyzing powers, $$A_{x}$$ A x and $$A_{y}$$ A y , are smaller than the ones for the cross section, partly due to larger uncertainties for these observables. However, also for these observables no satisfactory agreement is found for all angular combinations. This implies that the present models of a three-nucleon force are not able to provide a satisfactory description of experimental data.

scholarly journals MODELING OF THERMOCHEMICAL PROPERTIES AND GLASSFORMING TENDENCY OF THE MELTS OF TERNARY Mn–Al–Gd SYSTEM

2018 ◽  
pp. 46-50
Author(s):  
N. Kotova ◽  
N. Golovata ◽  
N. Usenko
Keyword(s):  
Ternary System ◽  
Binary Systems ◽  
Hard Spheres ◽  
Regular Solution Model ◽  
Ternary Systems ◽  
Ternary Alloys ◽  
Liquid Alloys ◽  
Thermochemical Properties ◽  
Ternary Compounds ◽  
Enthalpies Of Mixing

In the present work, the enthalpies of mixing of liquid alloys of the ternary Mn-Al-Gd system have been calculated using the regular solution model by the Redlich-Kister-Muggianu formula. Also a comparison was made of calculated values of enthalpies of mixing in this system with the experimentally determined thermochemical properties of liquid alloys of the Mn-In-Gd ternary system obtained previously. In general, we estimate that the values of the enthalpies of mixing in the Mn-Al-Gd ternary system should be more exothermic than in the Mn–In-Gd one. This fact can be explained taking into consideration the main features of the component interaction in the boundary binary systems, namely, such important characteristics as electronegativity of the components, their electron work functions and a large difference in size of atoms. It can be concluded that it is the binary Mn–Al system that makes a significant contribution to the formation energy of ternary alloys. An imaginary line drawn through the points of maximum curvature of the isoenthalpic lines is considerably shifted towards the binary Mn–Al boundary, thus expanding significantly the region of rather exothermic enthalpies of mixing in the corresponding ternary system. For the two indicated ternary systems the size mismatch entropy has been calculated within the framework of hard spheres model and the Sσ/kB parameter has been determined. On the basis of the comprehensive analysis carried out, the criteria for the probability of occurrence of regions of easy amorphization in these ternary systems are proposed. The determination of the topology of the mixing enthalpy surface and the Sσ/kB parameter for the melts of studied ternary systems together with the data on binary and ternary compounds existing in these systems allowed to reasonably assume the concentration regions where the investigated ternary alloys have tendency for easy amorphization while rapid cooling of the melt. The simultaneous realization of the following three conditions was taken as a criterion for the possible existence of a region of easy amorphization: the absolute value of the enthalpies of mixing is at least 6 kJ/mol, the Sσ/kB parameter is not less than 0.3–0.4 and a certain distance from the concentration region corresponding to the exact composition of binary or ternary compounds.

Color-Singlet and Color-Octet Contributions to J/ψ Photoproduction

1997 ◽  
Vol 12 (22) ◽  
pp. 3985-3994
Author(s):  
Michael Krämer
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Higher Order ◽  
Recent Experimental Data ◽  
Color Singlet ◽  
Color Octet ◽  
Theoretical Predictions ◽  
The Cross ◽  
The Impact

I discuss the impact of color-octet contributions and higher-order QCD corrections on the cross section for inelastic J/ψ photoproduction. The theoretical predictions are compared with recent experimental data obtained at HERA.

scholarly journals PROMPT PHOTON PRODUCTION IN p-p COLLISIONS

1995 ◽  
Vol 10 (20n21) ◽  
pp. 2941-2960 ◽  
Author(s):  
J. CLEYMANS ◽  
E. QUACK ◽  
K. REDLICH ◽  
D.K. SRIVASTAVA
Keyword(s):  
Experimental Data ◽  
Cross Section ◽  
Cross Sections ◽  
Systematic Study ◽  
Structure Functions ◽  
Photon Production ◽  
Prompt Photon ◽  
Centre Of Mass ◽  
The Cross ◽  
Photon Cross Section

A systematic study of the inclusive photon cross-section in p-p collisions is presented. The dependence of the γ rates on the renormalization and factorization scales is discussed. A comparison is made with experimental data for centre-of-mass energies ranging from 23 GeV to 1.8 TeV. Predictions of the cross-sections are given for two different sets of structure functions for RHIC and LHC energies.

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