DIVARENT EQUILIBRIUM IN MULTI-COMPONENT SYSTEMS

The structure of the phase complex of the six-component reciprocal system Na, K, Mg, Ca || SO4, Cl-H2O at 500C in the region of crystallization of anhydrite (CaSO4) was studied by the translation method, and variants of the formation of divariant fields during the transition of the system from the five-component to the six-component state were shown

STRUCTURE OF THE PHASE COMPLEX OF THE SYSTEM K,Mg,Ca||SO4,Cl-H2O AT 0°C

The translation method predicted phase equilibria on geometric images of the system K,Mg,Ca||SO4,Cl-H2O at 00 C. It was found that at 0 °C the studied system is characterized by the presence of 6 invariant points, 18 monovariant curves and 15 divariant fields. Based on the data obtained, a diagram of the phase complex of the K,Mg,Ca||SO4,Cl-H2O at 0°C and fragmented by divariant fields, as well as crystallization fields of individual equilibrium solid phases, was constructed.

Mixed Methods Evaluation - A Chinese Cancer Screening Program

This paper introduces the rapidly growing modern mixed methods research (MMR) and its application in a Chinese cancer screening program. While some previous researchers have incorporated quantitative and qualitative data in research, recent mixed methods developments have provided significant clarity that can guide those new to the MMR field. Understanding the context for using MMR and examining a complex mixed methods evaluation study in Taiwan can help illustrate opportunities for and application of mixed methods in Asians. The Taiwan Cervical Cancer Screening Education Program is used as an exemplar of a multi-phase complex mixed methods evaluation study showcasing various MMR designs. These include an exploratory sequential design to develop culturally sensitive study instrument, iterative concurrent and sequential mixed methods for intervention mapping, and an embedded mixed methods evaluation design to assess impact. Visual diagrams are introduced to facilitate communication of mixed methods design procedures and products in each phase.

Effect of 2CaO·SiO2 particles addition on dephosphorization behavior

The effect of the addition of 2CaO·SiO2 solid particles on dephosphorization behavior in carbon-saturated hot metal was investigated. The research results showed that the addition of 2CaO·SiO2 particles have little influence on desilication and demanganization, and the removal of [Si] and [Mn] occurred in the first 5 min with different conditions where the contents of 2CaO·SiO2 particles addition for the conditions 1, 2, 3, 4, and 5 are 0, 2.2, 6.4, 8.6, and 13.0 g, respectively. The final dephosphorization ratios for the conditions 1, 2, 3, 4, and 5 are 61.2%, 66.9%, 79.6%, 63.0%, and 78.1%, respectively. The dephosphorization ratio decreases with the increase of 2CaO·SiO2 particles in the first 3 min. The reason for this is that the dephosphorization process between hot metal and slag containing C2S phase consisted of two stages: Stage 1, [P] transfers from hot metal to liquid slag and Stage 2, the dephosphorization production (3CaO·P2O5) in liquid slag reacts with 2CaO·SiO2 to form C2S–C3P solid solution. The increase of 2CaO·SiO2 particles increases the viscosity of slag and weakens the dephosphorization ability of the stage 1. The SEM and XRD analyses show that the phase of dephosphorization slag with the addition of different 2CaO·SiO2 particles is composed of white RO phase, complex liquid silicate phase, and black solid phase (C2S or C2S–C3P). Because the contents of C2S–C3P and 2CaO·SiO2 in slag and the dephosphorization ability of the two stages are different, the dephosphorization ability with different conditions is different.

Phase complex of the system Na,Ca||SO4,CO3,HCO3-H2O at 100 ºC

The article discusses the results of determining the possible phase equilibria in geometric images of a five-component reciprocal water-salt system of sulfates, carbonates, sodium bicarbonates and calcium at 100 ºC with subsequent construction of its phase complex diagram. The laws that determine the structure of the phase complex diagram of this system are needed to be obtained for the production of scientific data used both as a reference material and also to create the optimal conditions for the recycling of liquid waste industrial production of aluminum-containing sulfate carbonate and bicarbonate salts of sodium and calcium. It was established that the system under study at 100ºC is characterized by the presence of 31 divariant double saturation fields, 25 monovariant trisaturation curves and 14 invariant points.

Phase complex model of ternary reciprocal system Na+,Sr2+||WO42-,MoO42-

The paper presents the results of a theoretical study of the phase complex of a three-component reciprocal system consisting of sodium and strontium tungstates and molybdates. Previously, a literature review was conducted on data on phase equilibria in the condensed state of individual salts, binary faceting systems. In two Na2MoO4 – SrMoO4 and Na2WO4 – SrWO4 binary systems, a eutetic equilibrium is observed with the formation of solid phases corresponding to the system components, and in two other Na2MoO4 – Na2WO4 and SrMoO4 – SrWO4 binary systems, one phase of a continuous series of solid solutions crystallizes. Based on the mathematical model of the molar balance, one can uniquely determine the quantities of reaction products, the molecular formulas of solid solutions, and the equations of chemical reactions for an arbitrary mixture of system components. This model represents a set of algebraic equations by which the balance is calculated. To build a 3D computer model, the paper presents the equations for the conversion of coordinates from barycentric to Cartesian. The model is implemented in concentration-temperature coordinates using the KOMPAS-3D program using experimental data on the system. The model is built in two interpretations: based on data on the faceting elements and on the basis of all available data about the system. Comparison of the two models makes it possible to evaluate the predictive ability carried out using 3D modeling. From this comparison, it was found that using the 3D model it is possible to conduct a preliminary a priori forecast of phase equilibria in order to identify the structure of phase diagrams at the qualitative and quantitative levels. The projection of the crystallization polytherm onto the square of the compositions is represented by two fields of solid solutions – Na2MoxW1-xO4 and SrMoxW1-xO4. Isothermal and polythermal sections were constructed. The system implements di- and monovariant equilibria.