Showing papers on "Ternary operation published in 1995"

Handbook of Ternary Alloy Phase Diagrams

Abstract: The largest collection of ternary phase diagrams and related crystal structure data ever assembled can be found in this 10 volume set. Some features of the reference set: 18,000 published diagrams Exhaustive bibliographies by Dr. Prince Includes diagrams from the compilations from the International Programme for Alloy Phase Diagrams 7,380 ternary systems ternary phase diagrams for 3,317 alloy systems Crystallographic data on 7,050 systems Includes liquidus projections, isotherms, isopleths, and pseudobinaries All diagrams were redrawn to uniform standards for easy use and comparison Temperatures given in degrees C and all compositions given in atomic relative orientation of elements is standardized (no rotating or mirroring needed) Angle between composition scales in all horizontal views (projections and isothermal sections) standardized at 60 degrees More than 43,000 citations of included literature most composition scales are identical within a diagram Boundary regions adjusted to critically evaluated binary diagrams

Band gap and stability in the ternary intermetallic compounds NiSnM (M = Ti, Zr, Hf): A first principles study

Abstract: The structural stability and electronic properties of the ternary intermetallic compounds NiSnM (M=Ti,Zr,Hf) and the closely related Heusler compounds ${\mathrm{Ni}}_{2}$SnM are discussed using the results of ab initio pseudopotential total-energy and band-structure calculations performed with a plane-wave basis set using the conjugate gradients algorithm. The results characterize the lowest-energy phase of NiSnM compounds, with a SnM rocksalt structure sublattice, as narrow-gap semiconductors with indirect gaps near 0.5 eV, while the ${\mathrm{Ni}}_{2}$SnM compounds are described as normal metals. Two other atomic arrangements for NiSnM in the MgAgAs structure type result in energetically unfavorable compounds that are metallic. The gap formation in the lowest-energy structure of NiSnZr and relative stability of the three atomic arrangements are investigated within a tight-binding framework and by considering the decomposition of each ternary compound into a binary substructure plus a third element sublattice. The stabilization of the lowest-energy phase of NiSnZr is found to be mainly due to the relative stability of the SnZr rocksalt substructure, while the opening of the gap induced by the addition of the symmetry-breaking Ni sublattice makes a relatively minor contribution. The results from the theoretical calculations for the NiSnM compounds are compared with the existing experimental data. From analysis of structural and chemical trends in the NiSnM compounds, CoVSn is predicted to be a semiconducting intermetallic compound in the MgAgAs structure type. Preliminary first-principles calculations suggest an indirect gap of 0.8 eV.

Self-assembling amphiphilic systems

Abstract: Self-assembling Systems - Surfactants Lipids Fluid Mixtures - Binary and Ternary Systems Containing Amphiphile lnterfaces - Liquid-liquid Theories of Interfaces, Surface Phase Transitions Wetting Membranes.

The kinetic mechanism of Ran--nucleotide exchange catalyzed by RCC1.

Abstract: The interaction of Ran, a Ras-related nuclear GTP-binding protein, with its guanine nucleotide exchange factor RCC1 has been studied by equilibrium and transient kinetic measurements using fluorescent nucleotides The four-step mechanism of catalyzed nucleotide exchange involves the formation of ternary complexes consisting of Ran, RCC1, and GXP as well as a nucleotide-free dimeric RanRCC1 complex This model is sufficient to describe all experimental data obtained, so that no additional reaction steps must be assumed All the rate and equilibrium constants for the four-step mechanism have been determined either experimentally or from a simultaneous theoretical fit to all experimental data sets The affinities of RCC1 to RanGDP and RanGTP are similar (13 x 10(5) and 18 x 10(5) M-1, respectively) and are high enough to allow formation of the ternary complex under appropriate concentration conditions In the absence of excess nucleotide and at low Ran concentrations, GDP (or GTP) can be efficiently displaced by excess RCC1 and the ternary complex can be produced The affinities of both nucleotides (GDP or GTP) to Ran in the corresponding ternary complexes are reduced by orders of magnitude in comparison with the respective binary complexes The reduction of affinity of both nucleotides in the ternary complexes leads to a dramatic increase in the dissociation rate constants by similar orders of magnitude (from 15 x 10(-5) s(-1) to 21 s(-1) for GDP) and thus to facilitated nucleotide exchange The quantitative results of the kinetic analysis suggest that the exchange reaction does not per se favor the formation of the RanGTP complex, but rather accelerates the formation of the equilibrium dictated by the relative affinities of Ran for GDP/GTP and the respective concentrations of the nucleotide in the cell The extent of RanGTP formation in vivo can be calculated using the constants derived

A preliminary study of the effect of ammonia on particle nucleation in the marine boundary layer

Abstract: A ternary nucleation model for the H2SO4-NH3-H2O system is presented in an effort to examine the effect of NH3 on heteromolecular homogeneous nucleation in the marine boundary layer (MBL). The results from this nucleation model suggest that ammonia could, in fact, enhance the nucleation rate over that of the binary system, H2SO4-H2O. The magnitude of this enhancement is introduced as an enhancement ratio, which, in principle, is applicable to any binary nucleation rate for H2SO4-H2O. Also presented are preliminary results from a simple aerosol model using this enhancement ratio. These results suggest that under conditions typical of the marine environment it may be possible to produce enough particles to balance the various particle sinks characteristic of the MBL.

A general solution model for predicting ternary thermodynamic properties

Abstract: All current models used to predict ternary thermodynamic properties from binaries improperly assume that the selected binary compositions in a ternary model are independent of ternary considered. As a result, it will require human interference for selecting models and arranging components to three apexes of a triangle, and will lead to an unacceptable result in some limiting case. A reasonable assumption should be that the selected binary compositions are closely related to the ternary itself. On the basis of this idea, a completely new model has been suggested. It seems that this new model is more reasonable theoretically from consideration, more reliable in practical application and more realistic to use in computerized thermodynamic and phase diagram calculation.

Synthesis of Titanium Silicon Carbide

Abstract: Synthesis of bulk titanium silicon carbide (Ti3SiC2) from the elemental Ti, Si, and C powders has been accomplished for the first time, using the arc-melting and annealing route. The effects of various parameters on the phase purity of the Ti3SiC2 have been examined, including the starting composition of the powders, compaction technique, arc-melting of the samples, and temperature and time of anneal. The best bulk samples, containing about 2 vol% TiC as the second phase, were made from Si-deficient and C-rich starting compositions. Based on electron probe microanalysis data from a number of bulk samples, it appears that Ti3SiC2 exists over a range of compositions; the Ti-Si-C ternary section has been modified to reflect this. The purest samples of the ternary phase were obtained by leaching powders of silicide-containing samples in diluted HF, and contained over99vol%Ti3SiC2.

A lattice Boltzmann model of ternary fluid mixtures

Abstract: A lattice Boltzmann model is introduced which simulates oil-water-surfactant mixtures. The model is based on a Ginzburg-Landau free energy with two scalar order para meters. Diffusive and hydrodynamic transport is included. Results are presented showing how the surfactant diffuses to the oil-water interfaces thus lowering the surface tension and leading to spontaneous emulsification. The rate of emulsification depends on the viscosity of the ternary fluid.

Thermodynamic study of phase equilibria in the Pb-Sn-Sb system

Abstract: A thermodynamic analysis of the phase equilibria in the Pb-Sn-Sb ternary system was conducted. A regular solution approximation based on a two-sublattice model was adopted to describe the Gibbs energy of formation of the individual phases in the binary and ternary systems. In the case of some component binary systems, the effect of pressure also was considered. Experimental data obtained by differential thermal analysis (DTA) and electron probe microanalysis (EPMA) in the present study, along with literature data on phase boundaries and thermochemical properties, form the basis for the evaluated thermodynamic parameters used in the calculation. Calculated and experimental phase boundaries agree fairly well.

Oxidation of Multicomponent Two-Phase Alloys

Abstract: The high-temperature corrosion behavior of two-phase alloys presents a number of differences compared to that of single-phase alloys. These differences are mainly a consequence of the limitations that the presence of two phases impose on the diffusion of the alloy components. In this review, it is shown that the exclusive scale formation of the more stable, slow-growing oxide is more difficult on a two-phase alloy, requiring a higher concentration of the more reactive alloy component than for a corresponding single-phase alloy. The main types of corrosion behavior for binary two-phase alloys are also considered, showing that if diffusion in the alloy is slow the scale structure will closely reflect that of the starting material. When diffusion in the alloy is not negligible, the scale structure becomes similar to what forms on single-phase alloys. The oxidation of two-phase ternary alloys is shown to be even more complex than the two-phase binary alloys. The principal added complexity compared to the binary alloys is that diffusion in the ternary alloys may also occur in the presence of two metal phases, as a result of an extra degree of freedom in the ternary system. The oxidation behavior of two-phase ternary alloys is discussed in the context of a number of recent experimental results.

Vapor + Liquid Equilibria for the Ternary System Methane + Ethane + Carbon Dioxide at 230 K and Its Constituent Binaries at Temperatures from 207 to 270 K

Abstract: Vapor-liquid equilibrium data for the binary system methane + carbon dioxide were measured at 230, 250, and 270 K. The ethane + carbon dioxide system was studied at 207, 210, 213, 230, 250, and 270 K, and the methane + ethane system was studied at 210, 230, 250, and 270 K. Ternary vapor-liquid equilibria for the methane + ethane + carbon dioxide system were measured at 230 K over the pressure range from 1.15 to 6.59 MPa. The Peng-Robinson equation of state was used to model the systems, and binary interaction coefficients are reported.

The Fe-A1-Ti system

Abstract: An extensive experimental investigation of the Fe-Al-Ti system by metallography, microprobe analysis, and XRD on quenched specimens and on diffusion couples is presented. Two isothermal sections at 800 and 1000 °C were established; they differ substantially from the existing (800 °C) or partly determined (1000 °C) diagrams. From these results, existence of the τ1 phase (Fe2AlTi) can be ruled out. Existence of the ternary compounds, τ2 (Al2FeTi) and τ3 (Al22Fe3Ti8), is confirmed. The composition limits of both phases were determined; they differ considerably from those given in earlier reports. The τ2 phase apparently exists in a cubic and a tetragonal polymorph, depending on composition. The cubic form exists at high titanium contents. At 1000 °C, the two polymorphs are separated by a miscibility gap. At compositions where the “X phase” (Al69Fe25Ti6) was previously reported, single-phase samples were obtained at both temperatures. From the present results, there is no evidence to assume that this is a new ternary phase rather than the ternary homogeneity range of the Al3Fe phase. In addition, extensions of the binary intermetallic phases into the ternary system were determined.

Effective masses of electrons and heavy holes in GaAs, InAs, A1As and their ternary compounds

Abstract: A comparative survey of known experimental and theoretical values of heavy-hole and electron effective mass in GaAs, InAs, and A1As is presented in this work. Recommended room-temperature values of these parameters are given for the above binary solutions and for their ternary compounds.

Pb-free Sn-Ag-Cu ternary eutectic solder

Abstract: A Pb-free solder includes a ternary eutectic composition consisting essentially of about 93.6 weight % Sn-about 4.7 weight % Ag-about 1.7 weight % Cu having a eutectic melting temperature of about 217° C. and variants of the ternary composition wherein the relative concentrations of Sn, Ag, and Cu deviate from the ternary eutectic composition to provide a controlled melting temperature range (liquid-solid "mushy" zone) relative to the eutectic melting temperature (e.g. up to 15° C. above the eutectic melting temperature).

Monte Carlo Studies of Ternary Semiconductor Alloys: Application to the Si 1 − x − y Ge x C y System

Abstract: The structural properties of Si-Ge-C alloys are studied using Monte Carlo simulations. The large size mismatch among the constituents is overcome by introducing atom-identity switches accompanied with neighbor-atom relaxations. A repulsive interaction between carbon atoms is found, so no clustering is observed. No formation of Ge-C bonds is foreseen. The lattice structural parameters show strong deviations from linear behavior.

Phase Separation of Ternary Mixtures: Symmetric Polymer Blends

Abstract: The dynamics of phase separation of ternary mixtures into two and three phases are analyzed numerically by solving the nonlinear spinodal decomposition equations in two dimensions. We find interesting interface effects during the decomposition process. Between any two α + β phases rich in components I and J respectively, the third component K segregates in the interface between α and β. We study the interface segregation effects in symmetric ternary polymer blends (i.e., with equal Flory interaction parameters between each pair of monomers and equal degrees of polymerization). This segregation phenomenon influences strongly the growth of a third phase with lowest equilibrium volume fraction. In the absence of hydrodynamics, the kinetics of the minority phase is determined by the topology of the segregation pattern initiated by the decomposition of the most unstable phases. Coarsening of the minority phase occurs at the junction of four or more majority phase domain boundaries. We examine the dynamical scaling and the growth laws for the late stages of separation into two and three phases. The growth law R(τ) ∼ τ 1/3 is always obeyed even when the structures are not self-similar. The self-similar regime is achieved very slowly in ternary systems.

A note on Quasi and Bi-ideals in Ternary semigroups

Abstract: -ASTRACr. In this paper e have studied the properties of Quasi-ideals and Biideals in ternary sni groups. We prove that every quasi-ideal is a hi-ideal in T but the converse is not true in general by giving several example in different

Vapour-liquid equilibrium of ternary mixtures of the refrigerants R125, R143a and R134a

Abstract: Ternary mixtures of R32, R125 and R134a of different compositions are recommended for replacing refrigerants R22 and R502. As a prerequisite for reliably calculating vapour pressure and phase equilibria of ternary mixtures within the relevant range of temperature and composition, VLE data of the three binary systems R32/R134a, R125/R134a and R32/R125 have been measured from −70°C up to the critical temperature. The real mixing behaviour of these binary systems is described by simple cubic equations of state, based only on precise experimental data of the critical properties and one value of the vapour pressure at T/Tc ≈ 0.7 for one mixture of nearly equimolar composition, respectively. Besides the properties of the pure substances, these data are sufficient to calculate the saturation pressure as well as the composition of the coexisting phases with rather high accuracy for both the binary and the ternary mixtures. This has been proved by comparison with experimental data for binary mixtures and for three ternary mixtures of different compositions.

Effects of early transition metal solutes on the D03-B2 critical temperature of Fe3Al

Abstract: The effects of dilute concentrations of the ternary solutes Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W on the critical temperature of the D0{sub 3}-B2 transformation in Fe{sub 3}Al were measured by differential thermal analysis (DTA). Additional studies by X-ray diffractometry showed that Mo, Ta, and W atoms occupied predominantly the 4(b) Wyckoff sites in D0{sub 3}-ordered Fe{sub 3}Al. Most solutes caused an increase in the D0{sub 3}-B2 transformation temperature, which was approximately linear in the limit of dilute solute concentrations. The efficacy of a particular ternary element in raising the D0{sub 3}-B2 transformation temperature was shown to be related to its metallic radius. The authors argue that the energetics of atom size mismatch are the major cause of the effects of ternary solutes on the D0{sub 3}-B2 transformation temperature of Fe{sub 3}Al.

On representation of

Abstract: A construction is presented which gives a possibility of describing ternary relations. Graphical representation of ternary relations is noted.

Effect of morphology on the behaviour of ternary composites of polypropylene with inorganic fillers and elastomer inclusions

Abstract: The effects of phase morphology, interfacial adhesion, rigid filler particle shape and elastomer volume fraction on the tensile yield strength of polypropylene (PP) filled with inorganic filler (CaCO3 or Mg(OH)2) and ethylene-propylene elastomer (EPR) were investigated. Separation of the filler and elastomer particles was achieved using maleic-anhydride-grafted PP (MPP) to enhance the filler-matrix adhesion. Encapsulation of the rigid filler by the elastomer was achieved using maleic-anhydride-grafted EPR (MEPR) to increase the filler-elastomer adhesion. The two limiting morphologies differ significantly in mechanical properties under tensile loading at the same material composition. Elastomer particles separately dispersed in the matrix enhance the shear banding in the bulk matrix which prevents the crazes growing from the filler surface from becoming unstable and, thus, increases the ductility of the material. Encapsulation by an elastomer layer on the filler surface relieves triaxial stresses at the filler surface, changing the major local failure mechanism from crazing to shear yielding and, hence, increasing the ductility of the material. Increase of the elastomer volume fraction also causes, in both cases, an increase in matrix ductility. Composite models are used to predict upper and lower limits of yield strength (σy) for the two limiting morphologies over an interval of elastomer volume fractions (V e) from 0 to 0.2 at a constant filler loading of 30 vol.% and over a filler volume fraction from 0 to 0.4 at a constant EPR content in the matrix. Satisfactory agreement was found between the experimental data and theoretical predictions.

Relativistic band structure of ternary II-VI semiconductor alloys containing Cd, Zn, Se and Te

Abstract: The relativistic band structure and band-gap bowing factors of ternary II-VI semiconductor alloys containing Cd, Zn, Se and Te are calculated by the ab initio self-consistent pseudopotential method with spin-orbit correction. The disorder in these alloys is modelled by the virtual crystal approximation (VCA). The numerical results thus obtained are compared with experimental data from photoluminescence spectroscopy. The experimental band-gap bowings for this family of alloys are always concave upwards. However, CdSexTe1-x and ZnSexTe1-x in general show much larger bowing factors than Cd1-xZnxSe and Cd1-xZnxTe. The former two alloys show a minimum in the band gap versus composition curve near x=0.35 while the latter two have it at x=0. Most of these qualitative trends are well explained by VCA. However, in order to explain the large bowing in the first two alloys, some kind of local order has to be incorporated in the calculation. It was found that a local cluster with AuCu-I-like structure, when relaxed, has quite a significant contribution to the bowing factors. The splittings in the band structure due to both spin-orbit and structural relaxation effects are also discussed.

A critical assessment and thermodynamic calculation of the boron-carbon-titanium (B-C-Ti) ternary system

Abstract: The B-C-Ti system has been critically assessed and calculated in the temperature region of 1400 °C up to the melting range employing the Thermocalc program system. The liquid phase is described using a substitutional model. The ternary solid solubility of boron in titanium carbide has been taken into account by using a two-sublattice model (Ti)1(B,C,Va),. The calculated isotherms and isopleths are presented and compared with the experimental information. The B-C-Ti reaction scheme is presented including the Ti3B4 phase.