Phase evolution during crystallization of nanocomposite alloys with Co:Fe ratios in the two-phase region of the binary Fe–Co phase diagram

2007 ◽  
Vol 101 (9) ◽  
pp. 09N108 ◽  
Author(s):  
P. R. Ohodnicki ◽  
S. Y. Park ◽  
H. K. McWilliams ◽  
K. Ramos ◽  
D. E. Laughlin ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Phase Evolution ◽  
Phase Region ◽  
Two Phase

Rheological and structural studies on heat-induced gelation of concentrated skim milk

1995 ◽  
Vol 62 (2) ◽  
pp. 257-267 ◽  
Author(s):  
Atsumi Tobitani ◽  
Haruyoshi Yamamoto ◽  
Toshiaki Shioya ◽  
Simon B. Ross-Murphy
Keyword(s):  
Phase Diagram ◽  
Laser Light ◽  
Skim Milk ◽  
Phase Region ◽  
Polymer Physics ◽  
Phase Behaviour ◽  
Two Phase ◽  
Effects Of Ph ◽  
Higher Temperature ◽  
Temperature Side

SUMMARYHeat-induced gelation of milk was studied using both rheological and structural techniques. The sample was a conventional skim milk, concentrated with an ultrafiltration membrane, which formed gels when heated at appropriate pH. We investigated some factors that are considered to affect the gelation, such as concentration, pH and rennet treatment. The gelation process was monitored with a high precision oscillatory shear rheometer and the structure of gels was evaluated with quasi-elastic laser light scattering. From these results the gelation and phase separation behaviour were determined. By combining the results for different concentrations a phase diagram was obtained, which indicated that skim milk had a two-phase region on the higher temperature side. The effects of pH and rennet treatment were also evaluated with the aid of this phase diagram. The results were discussed on the basis of concepts of the phase behaviour of polymers, which were successfully developed in polymer physics.

scholarly journals Ternary Phase Diagram of Model Dentin Adhesive Exposed to Over-wet Environments

2011 ◽  
Vol 90 (12) ◽  
pp. 1434-1438 ◽  
Author(s):  
Q. Ye ◽  
J. Park ◽  
J.S. Laurence ◽  
R. Parthasarathy ◽  
A. Misra ◽  
...  
Keyword(s):  
Phase Diagram ◽  
Ternary Phase Diagram ◽  
Water System ◽  
Phase Region ◽  
Partial Phase Diagram ◽  
Conjugate Pair ◽  
Two Phase ◽  
Phase Partitioning ◽  
Equilibrium Partition ◽  
Tie Lines

When adhesives and/or composites are bonded to the tooth, water in the environment can interfere with proper interface formation. Formation of water blisters and phase separation at the adhesive/dentin interface have appeared as new types of bond defects. To better understand this problem, we determined the near-equilibrium partition of the hydrophobic/hydrophilic components when exposed to over-wet environments. Model methacrylate-based adhesives were mixed with different amounts of water to yield well-separated aqueous and resin phases. It was found that less than 0.1% BisGMA but nearly one-third of the HEMA diffused into the aqueous phase, leaving the remaining resin phase relatively hydrophobic. A partial phase diagram was created for the ternary BisGMA/HEMA/water system. All the experimental phase partitioning data were plotted, and the points lay on a binodal curve that separated the single-phase region from the two-phase region. We obtained the 3 tie lines by connecting the 2 points of each conjugate pair of the phase partitioning data from the 3 sets of tripartite mixtures. Information about solubility, water miscibility, distribution ratio, and phase partitioning behavior could be obtained quantitatively. This type of phase diagram will provide a more thorough understanding of current adhesive performance and elucidate directions for further improvement.

Phase Relationships in Chemical Flooding

1978 ◽  
Vol 18 (05) ◽  
pp. 325-338 ◽  
Author(s):  
R.C. Nelson ◽  
G.A. Pope
Keyword(s):  
Phase Diagram ◽  
Phase Equilibrium ◽  
Phase Diagrams ◽  
Single Phase ◽  
Phase Region ◽  
Chemical Flooding ◽  
Two Phase ◽  
Equilibrium Phases ◽  
Flow Experiments ◽  
Diagram Representation

Abstract Results of laboratory chemical floods are presented to show that equilibrium phases observed presented to show that equilibrium phases observed in test tubes are representative of phases produced in core flow experiments. Consequently, many performance characteristics of chemical floods can performance characteristics of chemical floods can be explained and predicted from equilibrium surfactant-brine-oil phase diagrams. An oil reservoir under chemical flooding can be visualized as a series of connected cells with phase equilibrium attained in each. Fluid flow from phase equilibrium attained in each. Fluid flow from one cell to the next is governed, not so much by initial properties of the oil, brine, or chemical slug and drive, as by properties of equilibrium phases formed from those fluids. Three types of equilibrium phase environment are defined. Results of interfacial tension measurements and laboratory flow experiments indicate that chemical floods should be designed to keep as much surfactant as possible for as long as possible in the "Type III" phase environment while the surfactant is traversing the reservoir. Introduction Recent research shows that when certain surfactants of interest in chemical flooding are equilibrated with brine and oil, the phases formed can be represented by relatively simple triangular phase diagrams. Furthermore, Healy and Reed phase diagrams. Furthermore, Healy and Reed revealed that surfactant-rich equilibrium phases, while immiscible with brine and oil, can displace waterflood residual oil effectively. Other papers involving phases of chemical flooding systems have appeared subsequently. This paper extends the use of phase diagrams in chemical flooding research by presenting laboratory evidence that the same phases, observed when surfactant, brine, and oil are equilibrated in sample tubes, form and transport in a core under a chemical flood. This interrelationship between surfactant-brine-oil phase behavior and the characteristics of chemical flooding is reminiscent of the interrelationship between alcohol-brine-oil phase behavior and the characteristics of alcohol flooding as described by Tabor et al. We discuss here some consequences of local phase equilibrium in an oil reservoir under a chemical flood. First, we review briefly the phase diagram representation. Next, visualizing the core as a series of connected mixing cells in each cell of which phase equilibrium is attained, we prescribe conditions for effluent liquids, based on phase diagrams for surfactant-brine-oil systems. Then, we compare results of flow experiments with those prescribed conditions. prescribed conditions. PHASE DIAGRAM REPRESENTATION PHASE DIAGRAM REPRESENTATION Following Healy et al., Fig. 1 illustrates three types of generalized phase diagram for three quasi-single components - surfactant, brine, and oil. These phase diagrams represent what we define as "phase environments." A surfactant-brine-oil system in any of the three phase-environment types can equilibrate as a single phase or as multiple phases, depending on the over-all composition of phases, depending on the over-all composition of the system. At high-surfactant concentrations, all phase environments ideally are single phase. At lower-surfactant concentrations in a Type II(-) phase environment, two equilibrium phases are phase environment, two equilibrium phases are present. As indicated by the tielines in the present. As indicated by the tielines in the two-phase region, one phase is essentially pure oil and the other is a homogeneous phase containing surfactant, brine, and oil. Here, we shall call such a phase a "microemulsion." We use this term only to describe a phase containing surfactant, brine, and oil apparently in thermodynamic equilibrium with one or more other phases. The term does not suggest a particular concept regarding the structure of that phase. Thus, in a Type II(-) phase environment, the maximum number of equilibrium phases is two. When surfactant, brine, and oil are plotted as in Fig. 1, the tielines in the two-phase region have a negative slope; hence the "II(-)" designation. SPEJ P. 325

Ab INITIO CALCULATION OF THE LixCoO2 PHASE DIAGRAM

1997 ◽  
Vol 496 ◽  
Author(s):  
Anton Van Der Ven ◽  
Mehmet K Aydinol ◽  
Gerbrand Ceder
Keyword(s):  
Phase Diagram ◽  
First Principles ◽  
Driving Forces ◽  
Intercalation Compound ◽  
Phase Region ◽  
Metal Insulator Transition ◽  
Two Phase ◽  
Metal Insulator ◽  
The Past ◽  
Li Batteries

ABSTRACTThe electrochemical properties of the layered intercalation compound LiCoO2 used as a cathode in Li batteries have been investigated extensively in the past 15 years. Despite this research, little is known about the nature and thermodynamic driving forces for the phase transformations that occur as the Li concentration is varied. In this work, the phase diagram of LixCoO2 is calculated from first principles for x ranging from 0 to 1. Our calculations indicate that there is a tendency for Li ordering at x = 1/2 in agreement with experiment [1]. At low Li concentration, we find that a staged compound is stable in which the Li ions selectively segregate to every other Li plane leaving the remaining Li planes vacant. We find that the two phase region observed at high Li concentration is not due to Li ordering and speculate that it is driven by a metal-insulator transition which occurs at concentrations slightly below x < 1.

THE THERMODYNAMIC PROPERTIES AND PHASE DIAGRAM OF THE GOLD–CADMIUM SYSTEM BY THE ISOPIESTIC METHOD

1965 ◽  
Vol 43 (8) ◽  
pp. 2319-2327 ◽  
Author(s):  
L. J. Bartha ◽  
W. A. Alexander
Keyword(s):  
Phase Diagram ◽  
Free Energy ◽  
Phase Region ◽  
Isopiestic Method ◽  
Partial Molar Free Energy ◽  
Gold Alloys ◽  
Heat Of Solution ◽  
Molar Free Energy ◽  
Phase Boundaries ◽  
Two Phase

Activities of cadmium in gold alloys with up to 50 atom % Cd have been determined by an isopiestic method. The partial molar free energy, entropy, and heat of solution in the alpha and beta phases are calculated between 500 and 600 °C. The phase boundaries have been observed between 16 and 60 atom % above 400 °C. The boundaries of the two-phase regions α2 + β and β + δ′ are found at somewhat different concentrations than before, but the two-phase region α + α2 was not observed.

Can Amortization Bs Induced by Ion Mixing in Ag-Cu and Ag-Ni Systems?

1985 ◽  
Vol 54 ◽  
Author(s):  
B. X. Liu ◽  
L. J. Huang ◽  
J. Li ◽  
S. Ma
Keyword(s):  
Phase Diagram ◽  
Amorphous Phase ◽  
Equilibrium Phase ◽  
Structural Difference ◽  
Liquid Nitrogen Temperature ◽  
Equilibrium Phase Diagram ◽  
Heat Of Formation ◽  
Phase Region ◽  
Two Phase ◽  
Amorphous Phase Formation

ABSTRACTThe extended Structural Difference Rule for amorphous phase formation states that an amorphous phase can be obtained by ion mixing with an alloy with a composition lying in a two-phase region in the equilibrium phase diagram. This criterion has to respond to the challenge that no amorphous alloy has been formed in some early studied systems exhibiting a two-phase region character, e.g. Ag-Cu(typical eutec-tic),Ag-Ni(almost entirely immiscible),etc‥We performed ion mixing experiments for several systems at liquid nitrogen temperature using Xe ions with low current density. Amorphization was indeed observed in both Ag-Cu and Ag-Ni samples, as two halos were seen by TEM SAD immediately after adequate doses ion mixing. These not only support our two-pnase region rule, but also show the possibility of amorphization in a system(Ag-Ni) that has large positive heat of formation.

The Effect of Molecular Architecture on the Phase Diagram and Mobility of a Polymer Blend Exhibiting a Lower Critical Solution Temperature: Cycles Mixed with Linear Chains.

1991 ◽  
Vol 248 ◽  
Author(s):  
Maria M. Santore ◽  
Gregory McKenna ◽  
Charles Han
Keyword(s):  
Phase Diagram ◽  
Phase Separation ◽  
Lower Critical Solution Temperature ◽  
Phase Region ◽  
Solution Temperature ◽  
Free Energy Function ◽  
Molecular Architecture ◽  
Two Phase ◽  
Critical Solution Temperature ◽  
Linear Chains

AbstractWe examine the role of molecular architecture on the phase diagram of the PS/PVME (poly[styrenel /poly[vinyl methyl ether]) blend, a mixture which in previous studies with linear chains exhibited a lower critical solution temperature, (LCST) i.e. it phase separated on heating. In this investigation, two blends with components exceeding the critical molecular weight for entanglement were compared: one consisting of linear PS and PVME and a second with cyclic PS and linear PVME. Cloud point experiments over a broad composition range reveal that the blend containing cyclic PS undergoes phase separation at temperatures 7-8 °C higher than the analogous linear blend. In other words, the mixture of cycles and linear chains is more thermodynamically stable than the mixture of two linear chains.The LCST nature of the system facilitates examining chain mobility by considering the phase separation kinetics. Time-resolved light scattering studies of blends near their critical compositions tracked the spinodal decomposition following a rapid temperature jump from the one-phase to the two-phase region. An analysis of the scattering intensity growth ultimately led to mutual diffusion coefficients whose temperature dependence confirmed the observed cloud points. An approximation of the second derivative of the free energy function based on SANS studies of the linear PS/PVME blend allowed us to estimate mutual mobilities. The values determined for the cycle-containing blend were considerably lower than those for the blend of linear chains at these molecular weights.

Solution Properties and Phase Behavior of Ammonium Hexylene Octyl Succinate in Water and Water-Oil System

1970 ◽  
Vol 3 (1) ◽  
Author(s):  
Md. Hamidul Kabir ◽  
Ravshan Makhkamov ◽  
Shaila Kabir
Keyword(s):  
Critical Micelle Concentration ◽  
Phase Behavior ◽  
Liquid Crystalline ◽  
Carbon Number ◽  
Phase Region ◽  
Solution Properties ◽  
Middle Phase ◽  
Two Phase ◽  
Lamellar Liquid Crystal ◽  
Drug Ingredient

The solution properties and phase behavior of ammonium hexylene octyl succinate (HOS) was investigated in water and water-oil system. The critical micelle concentration (CMC) of HOS is lower than that of anionic surfactants having same carbon number in the lipophilic part. The phase diagrams of a water/ HOS system and water/ HOS/ C10EO8/ dodecane system were also constructed. Above critical micelle concentration, the surfactant forms a normal micellar solution (Wm) at a low surfactant concentration whereas a lamellar liquid crystalline phase (La) dominates over a wide region through the formation of a two-phase region (La+W) in the binary system. The lamellar phase is arranged in the form of a biocompatible vesicle which is very significant for the drug delivery system. The surfactant tends to be hydrophilic when it is mixed with C10EO8 and a middle-phase microemulsion (D) is appeared in the water-surfactant-dodecane system where both the water and oil soluble drug ingredient can be incorporated in the form of a dispersion. Hence, mixing can tune the hydrophile-lipophile properties of the surfactant. Key words: Ammonium hexylene octyl succinate, mixed surfactant, lamellar liquid crystal, middle-phase microemulsion. Dhaka Univ. J. Pharm. Sci. Vol.3(1-2) 2004 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website

scholarly journals Revisiting the Bøggild Intergrowth in Iridescent Labradorite Feldspars: Ordering, Kinetics, and Phase Equilibria

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 727
Author(s):  
Shiyun Jin ◽  
Huifang Xu ◽  
Seungyeol Lee
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Atom Probe ◽  
Phase Region ◽  
Two Phase ◽  
Subsolidus Phase ◽  
Plagioclase Feldspar ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission

The enigmatic Bøggild intergrowth in iridescent labradorite crystals was revisited in light of recent work on the incommensurately modulated structures in the intermediated plagioclase. Five igneous samples and one metamorphic labradorite sample with various compositions and lamellar thicknesses were studied in this paper. The lamellar textures were characterized with conventional transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). The compositions of individual lamellae were analyzed with high-resolution energy-dispersive X-ray spectroscopy (EDS) mapping and atom probe tomography (APT). The average structure states of the studied samples were also compared with single-crystal X-ray diffraction data (SC-XRD). The Na-rich lamellae have a composition of An44–48, and the Ca-rich lamellae range from An56 to An63. Significant differences between the lamellar compositions of different samples were observed. The compositions of the Bøggild intergrowth do not only depend on the bulk compositions, but also on the thermal history of the host rock. The implications on the subsolidus phase relationships of the plagioclase feldspar solid solution are discussed. The results cannot be explained by a regular symmetrical solvus such as the Bøggild gap, but they support an inclined two-phase region that closes at low temperature.

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