摘要:

In this short letter we further justify the concept of an effective PercusYevick temperature in liquid metals, in analogy with the well known effective Debye temperature in solids, which describes many of the properties of the phonons of the solid in one parameter.

ISSN:0031-9104    

DOI:10.1080/00319107508083824

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

In this note, we utilize the recently calculatd long wavelength limit of the “liquid virtual crystal” model of binary alloy liquid structure factor at the melting temperature, STMAB(0), to estimate the long-volume binary liquid alloys. We compare the calculate sound velocities to the available experimental sound velocities in these liquid binary alloys and find reasonable agreement.

ISSN:0031-9104    

DOI:10.1080/00319107508083825

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

In this paper, we extend the theory of melting entropy of metals, of Omini, based on the Percus-Yevick collective coordinate theory of liquids, to binary liquid alloys. We reformalate Omini's use of the Percus-Yevick theory to include binary liquid alloys and calculate the long wavelength limit of the binary liquid alloy structure factor as a function of solute concentration for the systems: Li-Na, K-Rb. Rb-Cs, Al-Zn, Zn-Ca and AI-Ga which are the most nearly equi-valent and equi-volumeatom pairs Omini worked with.

ISSN:0031-9104    

DOI:10.1080/00319107508083826

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

In this brief note, we utilize the 3N collective coordinate theory of liquids of Percus and Yevick1as applied to the phenomenon of melting by Omini2to calculate the sound Velocities in various simple liquid metals at their melting temperatures. We perform this calculation by taking derivatives of Omini's2calculated Percus-Yevick dispersion relations for their “liquid phonon” collective coordinate elementary excitations of the liquid. We compare these calculated sound velocities with experimental data, where possible, to ascertain the validity of the liquid phonon dispersion relation as a source of sound velocities.

ISSN:0031-9104    

DOI:10.1080/00319107508083827

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

In this paper we compare the recent description of melting via the self consistent field scheme of Johannsson1with the Percus-Yevick2collective coordinate approach to the theory of liquids, as applied to the melting phenomenon and the liquid structure factor of liquid metals by omini3. We show that the formalism used to extract a self consistent order parameter naturally leads to the concept of a liquid phonon analogous to a paramagnon in the theory of ferromagnetic-paramagnetic or antiferromagnetic-paramagnetic phase transitions, which can readily be identified with Percus-Yevick2technique of decribing the liquid in terms of 3N collective coordinates. This description has been used very successfully by Omini3to relate the entropy of melting to the long wavelength limit of the liquid structure factor for a variety of simple metals, so that a relation can be demonstrated between the self consistent field parameter and melting via another route, the Percus-Yevick2theory. Lastly, we relate both the self consistent field (order) parameter and the energy of formation of a vacancy-interstitial pair, via the Percus-Yevick dispersion relation, tpo the Lindemann melting criterion parameter, the root mean square lattice displacemene of the atoms critical to melting.

ISSN:0031-9104    

DOI:10.1080/00319107508083828

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

The experimental procedure of determining the structure of a liquid by diffraction techniques is reformulated herein as a stochastic experiment subject to the data analysis formalism of statistical spectral analysis. Observed in such an experiment are averaged local microscopic fluctuations from the bulk density. The intensity function then represents a stochastic spectrum and it becomes necessary to statistically estimate a minimum bias, minimum variance covariance function which is the net radial distribution function. A low-pass tapered data window produces such an optimum estimate.

ISSN:0031-9104    

DOI:10.1080/00319107508083829

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

X-ray diffraction measurement were made at temperatures about 50°C above liquidus in the Pb-Bi system. Three partial structure factors Sij(Q) were evaluated from the observed X-ray intensities assuming that each Sij(Q) is independent on the relative abundance of the constituent elements in the alloys. The partial reduced distribution functions Gij(r) were also calculated. The functions Sij(Q) and Gij(r) have maxima which lie between those of the pure elements. The radii of the first coordination sphere show a linear dependence on the concetration as expected from random distribution of the atoms in liquid Pb-Bi alloys. A comparison was made between the partial and total structure factors obtained in this work and those calculated from the hard sphere model. Adequate agreement was obtained on the first peak, but good agreement of the damping behaviour and phase was not necessarily found.

ISSN:0031-9104    

DOI:10.1080/00319107508083830

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

The thermodynamics of eutectic type liquidus curves in compound forming systems is developed for the case when a single compound AμBμis formed. The liquidus curves are considered in three regions: (i) A-rich (ii) B-rich and that in which equilibrium conditions involve the compound (iii). In region (iii) the slope of the liquidus curve in the presence of the compound AμBμhas a multiplying factor μ-(μ+v)c and hence changes sign at c = μ/μ+v, in agreement with observation.

ISSN:0031-9104    

DOI:10.1080/00319107508083831

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor