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In this work, tensile samples of a Yttrium-alloyed nickel-base superalloy 718 were eletrochemically charged with hydrogen and compared with reference samples with no Y addition. It was shown that Y promoted an increase in the ductility of the material for both the hydrogenated and the reference samples, especially for the homogeneous deformation. This effect was attributed to the refinement of the microstructural features and the control of deleterious elements like sulphur and oxygen, mitigating the embrittling effect of hydrogen. Furthermore, the Y-alloying hampered the H ingress into the material and increased the critical concentration needed for fracture along the grain boundaries. [Display omitted] • Y-alloying increased the overall ductility of the alloy. • Loss of ductility due to H was lower for the Y-alloyed samples. • Y can provide more H trapping and lower the H ingress. • Y lowers the content of harmful elements and increases grain boundary cohesion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Localized bulging was observed in a section of the outermost tube of the superheater. • Severe degradation of the microstructure was evidenced in the bulging region. • A weld defect affected the steam flow and local heat transfer. • The heterogeneous flue gas flow induced localized overheating of the tube. • The failure was related to a conjunction of long time overheating and creep. During a maintenance shutdown, a localized bulging was observed in a section of the outermost tube of the superheater, an ASTM A213 grade T12 (UNS K11562), Cr-0.5Mo ferritic steel. The objective of this work was to investigate the failure of the steel tube, part of a L-shape superheater of a CFB boiler. The investigation was performed through microstructural characterization, chemical analysis, thermodynamic calculations, hardness measurements, tensile and creep tests, measurements of the oxide scale thickness on selected regions of the failed tube for determination of the remaining life assessment. It was concluded that the failure was due to a conjunction of long time overheating and creep. A welding defect (root dropout) caused an alteration of the steam flow and, therefore, impaired the proper heat transfer between the tube and the steam. In addition, the uneven flow of the flue gas induced a heterogeneous heat distribution along the tube length, particularly in the area facing the flue gas, evidenced by the erosion marks. The high local temperature resulted in intense oxidation, decarburization and degradation of the microstructure. As a consequence, the steel strength was reduced, with consequent bulging and failure. These points were reinforced by the results of the RUL assessment, where the value was negative at the referred region, meaning the end of its operational life. [ABSTRACT FROM AUTHOR]

Recent children's literature highlights themes that were banned in the past, such as homosexuality and particularly homoparental families. The present paper aims to analyze how homoparental families are represented in seven books published from 2007 on. The most recurrent tendency has been to feature love between men or women in a way similar to the ways heterosexual relationships are traditionally represented - drawing on the discourse of romantic love. Some of the frequent issues are family happiness and the resulting discussions about raising children and/or managing a house. However, two works skip this mainstream tendency, foregrounding children's curiosity for love and birth. [ABSTRACT FROM AUTHOR]

The influence of yttrium (Y) addition on the microstructure and mechanical properties of alloy 718 was examined by scanning and transmission electron microscopy, energy dispersive spectroscopy and tensile tests. Two alloys with 0.1% and 1.0% weight Y contents and a reference alloy without Y addition were melted, forged and solution heat treated. The yield of Y after melting ranged between 50% and 60% over the nominal value added. Y addition decreased the oxygen, nitrogen and sulfur contents of the alloy. The low-Y alloy presented a larger grain size, and the high-Y alloy presented a refined grain size owing to the intense precipitation of Y-rich phases. Microstructural analysis also revealed that the Y promoted (Nb,Ti)C carbide fragmentation. Considering the influence of this rare earth on the mechanical properties, there is an optimal yttrium content that can be added. The low-Y alloy showed an increase in ductility and no relevant variation in its mechanical strength. However, the high-Y alloy induced a sharp decrease in ductility, when compared to the low-Y alloy, owing to the embrittlement effect caused by the intense precipitation of Y-rich phases, such as Ni 17 Y 2 and Y 2 O 3. Image 1 • The increase of Y content had a relevant effect on lowering the impurity elements as O, S and N. • TEM/SAED analysis identified the Ni 17 Y 2 phase, which can present a minor Al content in solid solution. • A low addition of Y led to an average increase in elongation of 27%, compared to the sample without Y addition. • Higher Y addition decrease hardly the ductility. [ABSTRACT FROM AUTHOR]

Theoretical framework: Spontaneous Abortion (SA) in primigravidae triggers complex emotional reactions that occur outside the healthcare services. Objectives: To understand the experience of SA in primigravidae during the first trimester of pregnancy. Methodology: Qualitative and phenomenological study. The sample is purposive and composed of six participants. Data were obtained using open interviews and analysed based on Loureiro's (2002; 2006) proposal. Both contextual reliability and transferability were ensured. Results: The essence of the phenomenon is the shattering of a dream that results from the sudden deprivation of a desired pregnancy and motherhood. The structure found is divided into three central themes: experience of negative feelings; inner elaboration; desire to ensure motherhood. These themes coexist over time, although they manifest themselves differently. Conclusion: SA is an early pregnancy loss which brings about significant negative emotions and an effort of personal reorganisation, thus requiring attention and supervision by the healthcare professionals. [ABSTRACT FROM AUTHOR]