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Objectives To explore the outcome of monochorionic monoamniotic (MCMA) twin pregnancies affected by twin-to-twin transfusion syndrome (TTTS).Methods MEDLINE and EMBASE databases were searched for studies reporting the outcome of MCMA twin pregnancies complicated by TTTS. The primary outcome was intrauterine death (IUD); secondary outcomes were miscarriage, single IUD, double IUD, neonatal death (NND), perinatal death (PND), survival of at least one twin, survival of both twins and preterm birth (PTB) before 32 weeks' gestation. Outcomes were assessed in MCMA twins affected by TTTS not undergoing intervention and in those treated with amniodrainage, laser therapy or cord occlusion. Subgroup analysis was performed including cases diagnosed before 24 weeks. Random-effects meta-analysis of proportions was used to analyze the data.Results Fifteen cohort studies, including 888 MCMA twin pregnancies, of which 44 were affected by TTTS, were included in the review. There was no randomized trial comparing the different management options in MCMA twin pregnancies complicated by TTTS. In cases not undergoing intervention, miscarriage occurred in 11.0% of fetuses, while the incidence of IUD, NND and PND was 25.2%, 12.2% and 31.2%, respectively. PTB complicated 50.5% of these pregnancies. In cases treated by laser surgery, the incidence of miscarriage, IUD, NND and PND was 19.6%, 27.4%, 7.4% and 35.9%, respectively, and the incidence of PTB before 32weeks' gestation was 64.9%. In cases treated with amniodrainage, the incidence of IUD, NND and PND was 31.3%, 13.5% and 45.7% respectively, and PTB complicated 76.2% of these pregnancies. Analysis of cases undergoing cord occlusion was affected by the very small number of included cases. Miscarriage occurred in 19.2%, while there was no case of IUD or NND of the surviving twin. PTB before 32weeks occurred in 50.0% of these cases.Conclusions MCMA twin pregnancies complicated by TTTS are at high risk of perinatal mortality and PTB. Furt

The In2O3‑SnO2‑ZnO system is of special interest for applications as transparent conducting oxides and also transparent semiconductors. In the present work, a thermodynamic assessment for this system is discussed using all available experimental data on phase equilibria and thermodynamic properties. All subsystems including elemental combinations were considered in order to generate a self-consistent Gibbs energy dataset for further calculation and prediction of thermodynamic properties of the system. The modified associate species model was used for the description of the liquid phase. Particular attention was given to two significant solid solution phases: Spinel with the formula Zn(2–x)Sn(1–x)In2xO4 based on Zn2SnO4 and Bixbyite based on In2O3 and extending strongly toward the SnZnO3 composition according to the formula In(2–2x)SnxZnxO3. In addition to the component oxides, nine quasi-binary compounds located in the In2O3‑ZnO binary subsystem have also been included in the database as stoichiometric phases.

In the BOF process, the accurate control of Phosphorous removal up to ultra-low values is very important to ensure a high quality of the end–product. This has proven to be associated with several challenges, leading to a preferred usage of high priced low P iron ores. Thus, in the scope of the European BOFdePhos project, important thermodynamic and kinetic aspects of the dephosphorisation reaction such as the effect of solid phases on Phosphorous distribution and lime dissolution in a foamy slag were investigated. It was found that BOF slags are heterogeneous during a large period of the blow and also at the end of blow in most cases. The type and amount of solid phases is strongly affected by temperature and minor oxides content such as MgO-, MnO- and Al2O3-content. The consideration of solid phases formation in the slag, especially the P dissolving C2S_C3P phase, is crucial for a successful modelling and control of dephosphorisation. However, most of the Phosphorous distribution equations available in the literature were developed for homogeneous slags. Thus, a new approach for thermodynamic modelling of the P-distribution between a heterogeneous slag and liquid iron covering the total blowing period in converter was developed and incorporated in a kinetic dephosphorisation model. It was found that while the P distribution in a fully liquid slag was a strong function of temperature, CaO- and FeO-content, the P distribution in a heterogeneous slag depended further on temperature but also on the amount of solid phase as well as the basicity of the liquid slag phase. Even though the C2S_C3P phase can dissolve high amount of Phosphorous, the P-dissolution in the solid phase in the industrial process is associated with strong kinetic limitations. New strategies for the enhancement of dephosphorization control in the BOF converter, focusing on using the potential of the solid phase in removing Phosphorous, were developed., QC 20220621

In the context of integrated computational materials engineering (ICME) recycling covers processes at the end of the lifetime (EoL) of mechanical, electronic, or other components of machines and devices. Depending on the state in which they exist as EoL material they can either be used directly for new material production. This chapter provides a short overview of materials that are being recycled today and the methods applied. It focuses on computational methods applied in the field of recycling, the foremost being methods of computational thermochemistry since mutual solubilities, phase transformations, and reactions as well as heat balances play the most important part in recycling just as they do in standard production. The chapter discusses materials-centric recycling, product-centric recycling, physical separation methods and chemical separation methods. It shows various aspects and phenomena that affect the final recovery of all elements from a product, including the residence time of materials in the market, and subsequent metallurgical processing.

The FactSage computer package consists of a series of information, calculation and manipulation modules that enable one to access and manipulate compound and solution databases. With the various modules running under Microsoft Windows® one can perform a wide variety of thermochemical calculations and generate tables, graphs and figures of interest to chemical and physical metallurgists, chemical engineers, corrosion engineers, inorganic chemists, geochemists, ceramists, electrochemists, environmentalists, etc. This paper presents a summary of the developments in the FactSage thermochemical software and databases during the last six years. Particular emphasis is placed on the new databases and developments in calculating and manipulating phase diagrams.