Showing papers on "Ternary operation published in 1972"

Linear and nonlinear optical properties of some ternary selenides

Abstract: The refractive indices of the ternary A^{I}B^{III}C_{2}^{VI} semiconductors CuAlSe 2 , AgGaSe 2 , CuGaSe 2 , and AgInSe 2 have been measured over most of the transparency range of these crystals. The optical nonlinear coefficients for second-harmonic generation of AgGaSe 2 CuGaSe 2 , and AgInSe 2 have also been measured. Three-frequency colinear phase matching is analyzed in detail for AgGaSe 2 . The birefringences of the other three crystals are not sufficient to permit three-frequency colinear phase matching within the range of the measured index. The merits of AgGaSe 2 for nonlinear optical applications are evaluated in comparison with other promising infrared nonlinear materials.

Diffusion-controlled precipitate growth in ternary systems I

Abstract: Diffusion-controlled precipitation in isothermal ternary systems of arbitrary constitution is analyzed theoretically. The treatment is applicable to isolated precipitates whose morphology is preserved during growth;i.e., planar surfaces, cylinders, spheres, spheroids, and ellipsoids. The analysis does not account for ternary diffusional interaction. For a particular bulk alloy composition, the problem is essentially to determine the precipitatematrix interface velocity and the phase diagram tie-line which defines the equilibrium concentrations at this interface. The concepts of interface composition and interface velocity contours on the ternary phase diagram are introduced as instruments for solution of this problem. The influence on these contours of various diffusivity ratios for the independent components and of precipitate morphology is investigated. The assumption that local equilibrium maintains at the precipitate-matrix interface is critically examined and it is suggested that there are many instances in which the assumption is invalid. Therefore, Hultgren’s concept of paraequilibrium is discussed and is incorporated into the present theoretical framework. The techniques developed in the analysis are applied to ferrite growth in the Fe-C-Mn system.

Linear and nonlinear optical properties of ternary A II B IV C 2 V chalcopyrite semiconductors

Abstract: The refractive indices of ZnSiAs 2 , CdGeP 2 , and CdGeAs 2 have been determined over a wide range of wavelengths and the optical nonlinear coefficient for second-harmonic generation from the 10.6-μ CO 2 laser have been measured. The absorption coefficient versus wavelength is given for the above materials as well as for ZnGeP 2 , a previously discussed material. Three-frequency phase-matched mixing is described for each material.

A novel method of determination of reactivity ratios in binary and ternary copolymerizations

Abstract: The determination of reactivity ratios is simplified by using an excess of one monomer (M1) at a time large enough that the copolymers will have a very small content of the other monomer (M2). In this case chain propagation takes place almost exclusively by addition to polymer radicals with a terminal M1-unit (P) and monomer consumption by propagation of P may be neglected. One reactivity ratio (r1) is obtained from monomer conversions by means of a simple integrated equation which is valid up to high conversions. A calculation is proposed in order to account for the neglected propagation via P. The other reactivity ratio (r2) is obtained from copolymerizations with excess M2. As the new method uses an integrated form of the MAYO equation it permits the determination of monomer conversions directly by gas chromatography of unreacted monomers. Thus, if desired, analysis of copolymers can be avoided. The gas chromatographic method has been tested with the radical copolymerization of styrene and methyl methacrylate. In ternary and quaternary copolymerizations the new method offers particular advantages.

The phase equilibrium diagram of the system CaO-Al2O3-CaF2

Abstract: The phase equilibria of the system CaO-Al2O3-CaF2 have been studied by quenching in sealed platinum capsules followed by microscopic and X-ray examination of quenched products. The established phase diagram contains five ternary eutectics, two ternary peritectics and two invariant points of four-phase monotectic transformations. The system Al2O3-CaF2 has been established to be the stable diagonal of the reversible reciprocal system Al2O3 + 3CaF2 = 3CaO + 2AlF3. In the high-fluoride region a wide zone of liquid immiscibility has been found. The system also shows such rarely noticed but theoretically possible phenomena as the transformation of peritecticals into eutecticals and occurrence of three different primary fields under single continuous zone of liquid immiscibility.

Chemical aspects of glass formation in telluride systems

Abstract: The compositional dependence of the electrical activation energy, the optical absorption and the glass transition temperature in typical binary, pseudo-binary and ternary glass forming telluride systems has been measured in an effort to correlate chemical binding with physical properties. A modification of the valency satisfaction model to include chemical ordering effects is required to account for the property singularities observed in the GeTe system at the composition GeTe2. The ordering effects in Te-based alloys containing Ge are further verified by an endothermic disordering reaction in these liquids peaking between 400–475°C depending on composition.

Multicomponent diffusion and vapor‐liquid equilibria of dilute organic components in aqueous sugar solutions

Abstract: A technique for direct measurement of the differential diffusion coefficients in a ternary system of water, sugar, and a dilute organic species is described. The individual sugars were d-fructose, d-glucose, and sucrose; and ethyl alcohol, ethyl acetate, n-butyl acetate, and n-hexanal individually constituted the dilute organic species. The four ternary diffusivities were obtained over a range of sugar concentrations by the use of horizontal diaphragm cells, a differential interferometer, a flame-ionization gas-liquid chromatograph and postulation of the validity of the Onsager reciprocal relations. The equilibrium partial pressures of the dilute organic species over these solutions have also been measured, using a vapor head space chromatographic technique.

Growth of ternary composites from the melt: Part II

Abstract: Ternary alloys from the aluminum-rich corner of the Al-Cu-Ni system were unidirectionally solidified under a wide variety of growth conditions. Plane front solidification was achieved at sufficiently high thermal gradients and slow growth rates. Conditions necessary to cause planar interface breakdown in both two and three phase alloys compare well to those predicted by a simple constitutional supercooling criterion. Nonplanar microstructures obtained were cellular or dendritic and both single phase and two phase dendrites were observed. Microstructures of specimens solidified with planar and nonplanar fronts are discussed in terms of the ternary phase diagram and the solute “diffusion paths.”

Vapor-liquid equilibria of binary and ternary systems containing hydrogen and light hydrocarbons

Abstract: The vapor-liquid equilibrium relations of the hydrogen-methane, the hydrogen-ethylene, The hydrogen-ethane, the hydrogen-methane-ethylene and the hydrogen-ethylene-ethane systems were determined by a static method at several temperatures from -25°C to -170°C and at pressures up to 100 atm. From the data obtained, features of the phase equilibria of hydrogen-light hydrocarbon mixtures are discussed. The Benedict-Webb-Rubin equation was successfully applied to predict the vapor-liquid equilibria of the present systems above the normal boiling point of the heaviest hydrocarbon.

Influence of phosphorus on the electrical properties of PdNiP amorphous alloys

Abstract: Ternary PdNiP alloys can be obtained amorphous by quenching from the liquid state within certain concentration ranges of the constituants. The approximate boundaries of the amorphous area in the ternary diagram have been obtained. The electrical resistivity was measured between 4.2 and 300°K and in some cases between 1.2 and 450°K. For a given phosphorus content of either 20 or 25 at %, the resistivity and its temperature coefficient at room temperature are practically independent of the ratio of Ni to Pd. For a given ratio of Ni to Pd, corresponding to the formula (Pd 50 −Ni 50 ) 100− x P x the room temperature resistivity of the alloys varies with phosphorus concentration. The temperature coefficient of resistivity decreases with increasing phosphorus content and becomes negative around 24 at % phosphorus. Around this composition, the alloys have a very small temperature coefficient which varies within ±2 × 10 −5 /°K from specimen to specimen.

Determination of tie-line directions in the metastable phase-separation regions of ternary systems

Abstract: It is shown that the method of determination of tie-lines as isotherms of glass transition can be effectively used in the case of metastable phase separation. The tie-lines in the phase-separation region of sodium-borosilicate glasses were determined by this method. The results are compared with those of tie-lines determinations by other methods. Some considerations about the development of phase-separation process in ternary systems are given. It is shown also that the measurements of Tg may give evidence of the existence of metastable three-phase separation.

A New Ternary Compound in Rare Earth-Cobalt-Boron System

Abstract: A new ternary boride RCo12B6 with a rhombohedral structure was synthesized by arc-melting in R-Co-B system, where R is a rare earth ion. From magnetic measurements, it was found that CeCo12B6 had a Curie temperature at 130°–140°K and exhibited a Curie–Weiss behavior in the paramagnetic region above 140°K.

A review of the diffusion path concept and its application to the high-temperature oxidation of binary alloys

Abstract: Ternary diffusion theory, particularly the concept of diffusion paths on a ternary phase diagram, is reviewed in terms of its application to the problem of binary alloy oxidation. To illustrate this applicability, the oxidation behavior of Fe-Ni, Fe-Cr. and Ni-Cr alloys at 1000°C is examined in detail.

Thermodynamics of binary and ternary solutions containing one interstitial solute

Abstract: The activity of a very dilute interstitial component is proportional to the ratio of filled to unfilled interstitial sites. In a liquid solution in which solvent and solute atoms are strongly bonded to form in effect molecules of a soluteABb, each solvent atom is regarded as providingb sites forB atoms. The activity of the solute and other properties of the solution are treated by the same equations as those describing the interstitial solution. Concentrations are stated in terms of the ratiosyi = ni/(n1 +n2) where components 1 and 2 are lattice atoms andi represents any component. The activity coefficient of the interstitial component is defined as Ϋ3 =a3/z3 where z3 = Y3J(1 —y3/b). Henry’s law for the solute at great dilution is Ϋ3 = constant. Examples are cited in which log Ϋ3 is a linear function ofy3 or in other cases ofz3. A simple form of the Gibbs-Duhem relation for ternary solutions is used to deduce the effects of an interstitial solute on the activities of the individual lattice components.

Ternary Complexes in Solution, XII. Models for Biological Mixed-Ligand Complexes: 2,2′-Bipyridyl-Cu2+-Oligoglycine Systems

Abstract: The stability constants of the binary Cu2+ complexes of glycine amide, diglycine, diglycine amide, triglycine, and tetraglycine were determined, as were those of the mixed-ligand Cu2+ systems containing 2,2′-bipyridyl and one of the mentioned oligoglycines. The results evidence that all these complexes have the same structure and, therefore, the binding sites of the ligands have to be the terminal amino group and the oxygen of the neighbored amide group. The stability differences between the ternary and the binary complexes are in agreement with this interpretation. It is of interest to note that these ternary complexes are significantly more stable than expected on statistical reasons. With increasing pH, the amide groups in the binary complexes are successively deprotonated. Thus, with tetraglycine finally all three amide protons are displaced, and the amide nitrogens are bound to the square-planar coordination sphere of Cu2+. As in the Cu2+-2,2′-bipyridyl 1 : 1 complex, only two coordination positions are left for the binding of the oligoglycine, in the tenary complexes, only one amide group can be deprotonated. An increase in pH with deprotonation of other amide groups leads to a displacement of 2,2′-bipyridyl, i. e. the simple binary complexes result. No evidence could be observed for the coordination of a deprotonated amide group to an apical position of the coordination sphere of Cu2+. Additionally, while the displacement of the first amide proton in the several binary Cu2+ oligoglycine complexes occurs over a large pH range (4 to 7), the deprotonation in all the mixed-ligand complexes takes place at pH approximately 8.

The mutual solubilities of titanium and boron in pure aluminum

Abstract: The mutual solubilities of titanium and boron in Al-Ti-B ternary melts were determined over the temperature range 700° to 1300°C and the results interpreted in terms of the assumption (for which there is considerable evidence1) that the solubilities of these elements are limited by their reaction together to form titanium diboride (TiB2) probably containing aluminium diboride. In the method used, ternary melts were sampled at progressively lowered temperature levels after allowing time for titanium diboride precipitated to settle out.

On the ternary phases AlxNbSe2 and CuxNbSe2

Abstract: The system AlxNbSe2 ( x = 0→ 2 3 ) was prepared and the phases were identified by X-ray diffraction. It was found that niobium diselenide is able to accommodate aluminum in the tetrahedral holes between the prismatic NbSe2 layers, up to the limit x ≈ 1 3 . In these compounds the 2s−NbS2-type structure is maintained. The AlxNbSe2 system is compared with the ternary phase CuxNbSe2 in which NbSe2 accommodates Cu in the tetrahedral holes up to x ≈ 2 3 , and in which on introduction of the copper atoms, the structure changes from the 2s−NbS2 type to the 2s−MoS2 type. Both Al 1 3 NbSe 2 and Cu 2 3 NbSe 2 , exhibit Pauli-paramagnetic behavior.

Correlation of the binodal curve in a ternary liquid mixture with one pair of immiscible liquids

Abstract: Xl = (ws + Wek - w~A)/(w~s - W~A) X2 = (W~B - Ws - wek)/(w~s - W~A) . The different symbols stand for the weight fractions of the homogenizing component (we) and of solvent B (ws) in the ternary systems along the binodal curve and for the weight fractions of solvent B in the solvent B-rich (w~s) or solvent A-rich (wgA )

Phase Equilibria in the System SrO-CdO-V2O5

Abstract: Phase equilibria in the system SrO-CdO-V2O5 in air were established from data obtained by DTA, quenching, and high-temperature solid-state reaction experiments. The SrO-V2O5 boundary system contains 4 compounds at SrO to V2O5 molar ratios of 4:1, 3:1, 2:1, and 1:1. A fifth compound with a molar composition of ∼10:3 with the apatite crystal structure was also found; it may, however, be a hydroxyapatite phase. The CdO-V2O5 system contains the compounds 3CdO·V2O5, 2CdO·V2O5, and CdO·V2O5. The latter compound exhibits a rapid reversible polymorphic transition at 180°C. Complete solid solubility exists in the SrO-CdO system. The most probable compatibility relations were determined from the data available for the SrO-CdO-V2O5 ternary system. Limited solid solubility exists between SrO·V2O5 and CdO·V2O5, and the high-temperature CdO·V2O5 polymorph is stabilized to room temperature by solid solution of SrO·V2O5. Evidence for the existence of 2 ternary compounds with limited local solid solubility is also presented.