Application of the Hoch-Arpshofen model to the SiO2CaOMgOAl2O3 system

The Hoch-Arpshofen model was applied to the SiO₂-CaO-MgO-Al₂O₃ system. First the binary interaction coefficients, obtained from the six binary systems, were used to calculate the Gibbs energy of formation of the ternary compounds present in the four ternary systems; then the calculated activities of SiO₂, CaO, and Al₂O₃ were compared with the measured activities. The calculated Gibbs energies of formation of anorthite, gehlenite, and cordierite agree with the measured energies; the measured enthalpies of formation of akermanite, diopside, merwinite, and monticellite must be multiplied by 0.568 ± 0.031 to obtain agreement. The Gibbs energy of formation of 3CaO-MgO-2Al₂O₃ was also calculated. The calculated activity data agree with some authors' measurements and not with others.     

Thermodynamic study of the KMgAlClSO4H2O system at the temperature 298.15 K

The Pitzer ion-interaction model has been used for thermodynamic simulation of the binary AlCl₃H₂O, Al₂(SO4)₃H2O, ternary KClAlCl₃H₂O, K₂SO₄Al₂(SO₄)₃H₂O, MgCl₂AlCl₃H₂O, MgSO₄Al₂(SO₄)₃H₂O, and the quaternary KClMgCl₂AlCl₃H₂O systems at T=298.15 K. The optimum values of the binary parameters of ionic interactions for aluminum solutions have been calculated using activity data up to saturation of solutions. The ternary parameters have been chosen on the basis of the compositions of saturated ternary solutions taking into account the unsymmetrical mixing terms. Good agreement between experimentally determined and calculated solubilities has been found. Important thermodynamic characteristics (thermodynamic solubility product, standard molar Gibbs energy of formation) of the solid phases (simple and double salts) crystallizing in the systems under consideration are determined.     

A thermodynamic evaluation of the FeMoC system

A new evaluation of the Fe-Mo-C system has been made using a sublattice model and including the magnetic effect. A set of parameter values describing the Gibbs energy of each individual phase was determined with a computerized optimization technique. It gives satisfactory agreement with the experimental information over a wide temperature range. Several diagrams and tables concerning phase equilibria are presented.     

Calculation of thermodynamic properties of LiFAlF3, NaFAlF3 and KFAlF3

The scheme of dissociation of cryolite in NaFAlF₃ melts is proposed and applied to the LiFAlF₃ and KFAlF₃ systems. The constants and enthalpies of dissociation for alkali-cryolites are evaluated from experimental data. The mole fractions of each proposed species at 1298K in these three melt systems are calculated, and the variation of alumina solubility in alkali-cryolite can be explained on the basis of the ionic structure for the MF- AlF₃ (M: Li, Na and K) melts. The thermodynamic properties and liquidus data of MF-AlF₃ systems are calculated by using the selected evaluated parameters. Some results are compared with experimental values.     

Thermodynamic properties of MoC

An evaluation of the Mo-C system has been made using a sublattice model. A set of parameter values describing the Gibbs energy of each individual phase was determined with a computerized optimization technique. It gives satisfactory agreement with the experimental information over a wide temperature range. Several diagrams and tables concerning phase equilibria are presented.     

Calculation of the FeZnSi phase diagram between 773 and 1173 K

The phase diagram for the Fe-Zn-Si system has been calculated from thermodynamic data for the binary systems. The excess Gibbs energies of the solid and liquid solutions in the ternary system are described by: ΔG^xs = ΔG^xs₁₂ + ΔG^xs₁₃ + ΔG^xs₂₃ + ΔG^xs₁₂₃ with: ΔG^xs_ij = x_ix_j(A_ijx_i + B_ijx_j)ΔG^xs₁₂₃ = A₁₂₃x₁x₂x₃ The ternary interaction parameter A₁₂₃ is obtained from experimental characteristics of the ternary diagram: temperature dependance on the solubility of Zn in Fe₃Si and FeSi in Zn. The diagram Fe-Zn-Si calculated between 773 and 1173 K is used for explaining diffusion path observed during galvanization of the Fe-Si alloys.     

Thermodynamic modeling of the ZrO system

In this study, the complete zirconium-oxygen system has been critically assessed at 1 at. from 300°C to liquidus temperatures. Thermochemical measurements and phase diagram data were used to model the Gibbs free energies of seven phases. Additionally, the ordered interstitial HCP-based solutions were included and considered as simple line compounds. By using the PARROT module in Thermo-Calc, it was possible to optimize the parameters of the models used to describe the Gibbs free energies of the HCP, BCC, Liquid, γ ZrO_2−x,β ZrO_2−x and α ZrO_2−x phases. The Gas phase was considered to behave ideally. Although phase diagrams including the stoichiometric zirconia phases have been assessed, this is the first time, to the best of our knowledge that a complete assessment of this system is published.     

A world-wide web service for calculating approximate AMBER CC and CN bond stretching and torsional parameters

A computer program implementing linear interpolation for the purpose of calculating approximate CC and CN bond stretching and twofold torsional parameters for the AMBER force fields has been constructed. The computer program is based on published data from the Kollman group, and the method has been extended to enable the use of π-bond orders for parameter calculation. The computer program is available for use through a user-friendly World-Wide Web page.     

A network model for the thermodynamics of multicomponent silicate Melts. I. Binary mixtures MOSiO2

We have developed a network model for the thermodynamics of liquid silicate mixtures. Variation of the interaction parameter with composition is incorporated quite naturally by assuming a functional dependence, not on the silica content, but on the actual degree of polymerization of the silicate network. In this paper, which describes the model for binary mixtures, the interaction parameter is fitted to activity data for binaries of SiO₂ with CaO, FeO, K₂O, MgO, MnO, Na₂O and PbO. For the system MgOSiO₂ we have also fitted the temperature-composition phase diagram.     

Remark on the HSUDU new algorithm for the longest common subsequence problem

One of the time bounds claimed for a recent algorithm computing the longest common subsequence of two strings is shown not to correct. While this fact considerably affects the performance of that algorithm, it also contributes to pose a few interesting questions.     

Gibbs energies of formation of Mn3C,M(Fe,Mn)3C and Mn23C6 from the ternary phase equilibria in the FeMnC system

The high temperature phase relations in the FeMnC system have been analyzed in light of the recently developed thermodynamic method by the authors to obtain the Gibbs energies of formation of Mn₂₃C₆ and Mn,C. A new thermodyn/amic treatment is outlined and applied to obtain the stability of the ternary carbide M(Fe,Mn)₃C without any a priori assumption of a solution model for the M₃C phase. The recommended Gibbs energies of formation for the Mn carbides, Mn₃C and Mn₂₃C₆ With γ-Mn (graphite) as the Standard states are:

The present method can be extended to obtain a consistent set of thermodynamic data for binary and ternary carbides from various ternary metal-metal-carbon phase relations.     

A Thermodynamic description and phase relationships of the FeCr system: Part II the liquid phase and the fcc phase

The high-temperature thermodynamic data and phase equilibria of the FeCr binary reported in the literature are assessed. A set of thermodynamic values for the liquid, bcc and fcc phases are obtained. These values are internally consistent and the calculated phase equilibria are in agreement with the measured phase boundary data. Metastable equilibria for the liquid and fcc phases are also calculated.     

A thermodynamic description and phase relationships of the FeCr system: Part I the BCC phase and the sigma phase

A generalized approach which was applied successfully to account for the magnetic contribution to the thermodynamic properties of FeNi is applied to FeCr. The predicted magnetic specific heats for two bcc alloys at x_Cr = 0.16 and 0.21 are in good agreement with the experimental data available in the literature. The magnetic Gihbs energy, enthalpy and entropy for the bcc phase are obtained accordingly. The nonmagnetic thermodynamic properties of the bcc phase are obtained primarily from thermochemical data as well as those for the sigma phase. The calculated stable and metastable equilibria involving the bcc and sigma phases are in reasonable agreement with data reported in the literature. The calculated metastable miscibility gap of the bcc phase is highly asymmetric and the calculated spinodals show unusual features.     

通用并行神经网络模拟系统GP^2N^2S^2

本文提出的基于Transputer阵列的通用并行神经网络模拟系统（GP^2N^2S^2）提供了高级神经网络描述语言及其编辑和编译器以及友善的执行环境，可将用户以串行方式编写的程序由系统自动地并行执行，能模拟现有的各种神经网络模型和用户自己开发的新模型。     

三位一体2——Trine 2

在《三位一体》这款近乎梦幻的动作游戏获得了巨大成功之后，得到巨大荣誉的制作小组并没有满足，用他们自己的话来说那就是：虽说能够制作完成《三位一体》让他们很开心，。但他们并没有感到十分满意，因为这个游戏还有继续加以挖掘的空间和价值。正因为如此，在《三位一体》上市后不久，他们就开始续作的策划，对于后续作品的要求就是“更多、更好”。