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Solid Solubility (solid + solubility)

Distribution by Scientific Domains
Polymers and Materials Science62%
Chemistry25%

Selected Abstracts

Solid Solubility and Precipitation in a Single-Crystal Alumina,Zirconia System

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2002
Matthew A. Stough
Solid solubility was examined in Zr-doped sapphire and Al-doped yttria-stabilized zirconia (YSZ) single crystals from 1200° to 1600°C. Specimens were fabricated via ion implantation of single crystals, followed by annealing in air. Secondary ion mass spectroscopy (SIMS) was used to quantify solute redistribution during annealing. Comparison of SIMS results with analytical electron microscopy (AEM) revealed an alumina solubility of 0.2,0.3 wt% in zirconia, and a zirconia solubility of 0.004,0.027 wt% in alumina. Direct imaging of zirconia precipitates revealed that tetragonal zirconia precipitates from supersaturated sapphire with the following orientation relationship: (100)tetragonal, (0001)sapphire and [01¯1]tetragonal, [12¯10]sapphire. [source]

Partition Behavior of Polycyclic Aromatic Hydrocarbons Between Aged Coal Tar and Water,

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2009
Lihua Liu
Abstract Coal tar aged in a large-scale, artificial aquifer experiment for five years was subsequently investigated for leaching behavior of polycyclic aromatic hydrocarbons (PAHs). After five years, the initially liquid coal tar had solidified and formed segregated particles with a grain size similar to that of the sandy aquifer material. The composition of the aged coal tar (ACT) with regard to PAHs was remarkably different from that of the original bulk coal tar (BCT), because most of the low-molecular-weight compounds had been depleted. Equilibrium aqueous-phase concentrations of 17 PAHs leaching from the aquifer material containing the ACT were measured from consecutive equilibration steps at increasing temperatures of between 25 and 100C using accelerated solvent extraction. The results showed 2-to 5,000-fold lower concentrations than those from BCT, indicating dramatic changes of dissolution behavior of PAHs from coal tar after the five-year aging period. Predictions based on Raoult's law with the subcooled liquid solubilities substantially overestimated the equilibrium aqueous-phase concentrations of the PAHs from ACT, whereas the estimations were reasonable if the solid solubilities were employed instead. The enthalpies of phase transfer from ACT to water were determined based on the van't Hoff equation. The resulting values agreed with the dissolution enthalpies of pure solid rather than subcooled liquid PAHs. [source]

Optimization of Mechanical Properties of NiAl-base Alloy by Suction Casting,

ADVANCED ENGINEERING MATERIALS, Issue 4 2006
W. Huai
The suction-cast NiAl-Cr(Mo)/Hf alloy exhibits a refined microstructure and extended solid solubility. Significant improvement in room temperature ductility and strength was achieved by adopting suction casting technique. In addition, their elevated temperature strength also got slightly increase. The optimized mechanical properties can be attributed to the fine interlamellar spacing, the extended solid solubility and the increased cell eutectic zone as well as the refined Heusler phase. [source]

Modeling the solid,liquid equilibrium in pharmaceutical-solvent mixtures: Systems with complex hydrogen bonding behavior

AICHE JOURNAL, Issue 3 2009
Ioannis Tsivintzelis
Abstract A methodology is suggested for modeling the phase equilibria of complex chemical mixtures with an equation of state (EoS) for the case where only limited experimental data exist. The complex hydrogen bonding behavior is explicitly accounted for and the corresponding parameters are adopted from simpler molecules of similar chemical structure and/or are fitted to Hansen's partial solubility parameters. The methodology is applied to modeling the solubility of three pharmaceuticals, namely acetanilide, phenacetin, and paracetamol, using the nonrandom hydrogen bonding (NRHB) EoS. In all cases, accurate correlations were obtained. The prediction ability of the approach was evaluated against predictions from the COSMO-RS model. A thorough discussion is made for the appropriate modeling of solid solubility considering the effect of the difference of the heat capacities of the solute in liquid and solid state, ,Cp = Cpl , Cps, in the determination of solid chemical potential and, also, of the polymorphism of drugs. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source]

Low-Temperature Sintering and Electromagnetic Properties of Copper-Modified Z-type Hexaferrite

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2002
Hongguo Zhang
The influence of the substitution of copper for cobalt on the low-sintering densification, microstructure, lattice parameters, and electromagnetic properties of planar Z-type hexaferrites, which have a stoichiometric composition of Ba3Co2(10.8,x) -Zn0.4Cu2xFe24O41, were investigated. The experimental results show that densification of the copper-substituted hexaferrite is dependent on the amount of copper substitution and sintering temperatures. XRD analysis reveals that the solid solubility of copper in Z-type hexaferrite is limited to x, 0.30. At the same time, the lattice parameters (a and c) of Z-type hexaferrites with copper substitution showed a small change, that is, decrease of a parameter in the basal plane and increase of the c axial. Moreover, the microstructure becomes more homogeneous and intragranular pores decrease considerably, but the temperature-stable range of the Z-type phase formation is narrow. The copper-substituted hexaferrites, with x= 0.20 and sintered at ,1125°C for 4 h, resulted in a high density sample of ,4.68 g/cm3 as the optimal value, good magnetic properties, and the enormous potentiality for fabrication of multilayer chip inductors used in hyper-frequencies. [source]

Order,disorder of oxygen anions and vacancies in solid solutions of La2TiO5 and La4Ga2O9

ACTA CRYSTALLOGRAPHICA SECTION B, Issue 5 2009
Marta Kasuni
Successful Rietveld refinements of seven compounds with the formulae La2Ti(1,x)GaxO(5,x/2), where x = 0.00, 0.20, 0.50, 0.70, 0.90, 0.95 and 1.00, were performed in order to describe the solid solubility between orthorhombic (Pnam) La2TiO5 and monoclinic (P21/c) La4Ga2O9. The relationship between the end-member structures, which are already known, is discussed; the space-group change is a consequence of ordering the oxygen vacancies that become more numerous as Ga is substituted for Ti. The structures of the solid solutions are also described. The lengths of cell edges obey Vegard's rule. [source]