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In the present work, the initial stages of KCl-induced high-temperature corrosion of a chromia-forming alloy (42Fe25Ni22CrWCuNbN), UNS S31035, is investigated by means of in situ environmental scanning electron microscope (ESEM) exposures in an O2/H2O gaseous environment up to 1 h at 450°C. Prior to the exposures, KCl particles were sprayed on the samples. In order to perform reliable in situ ESEM exposures, temperature calibration of the ESEM hot stage was done. Additionally, the in situ results were validated by reference tube furnace exposures, and thefeasibility of the ESEM technique for obtaining dynamic information regarding the chlorine-induced corrosion process of the steel is discussed. Relatively large oxide crusts, with sizes of several micrometers, formed in the vicinity of the KCl particles. In between the KCl particles, a thin double oxide scale (20 nm to 100 nm), consisting of a top layer rich in iron oxide and a bottom layer rich in chromia, developed all over the surface of the alloy. Metal chloride was present beneath the thin base oxide, at the alloy/oxide interface, which shows the corrosive nature of KCl toward UNS S31035 in the studied environment. However, no extensive corrosion occurred at these locations after the short exposure times used in this work (1 h). [ABSTRACT FROM AUTHOR]

The present study investigates the influence of HO and KCl on the high-temperature corrosion of the FeCrAl alloy Kanthal AF. Polished samples, with and without applied KCl, were exposed isothermally to O or O + HO at 600 °C. The samples were investigated using TGA, XRD, SEM/EDX, AES and IC. It was found that KCl accelerates corrosion and that a rapidly growing iron, chromium-rich oxide forms in both environments. Chromate formation and alloy chlorination are shown to initiate the formation of non-protective oxide scales. In addition, aluminium nitrides form in the alloy substrate in both environments. [ABSTRACT FROM AUTHOR]

A FeCrAl alloy was preoxidized to form a protective alumina scale, and the effect of KCl deposits on the alumina scale was investigated while exposed during 1 and 24 h at 600 °C. However, impurity concentrations in the alumina scale change the ion conductivity and hence affect its protective properties. Therefore, Auger electron spectroscopy and time-of-flight secondary ion mass spectrometry were used to characterize the alumina scales and detect traces of K and Cl. The results showed that K and Cl existed as large sharp-edged crystals surrounded by a dendritic network after 1 h. However, after 24 h, those were dissolved, and K together with Cl was detected only in the outer layer of the duplex alumina scale, which was formed during preoxidation. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to identify the sociobehavioural factors that influenced children's oral health during the COVID-19 pandemic., Methods: The online cross-sectional study was conducted in Al Jouf Province in the northern region of Saudi Arabia. A total of 960 parents of children aged 5 to 14 years were invited by multistage stratified random sampling. Descriptive, multinomial, and multiple logistic regression analyses were performed to estimate odds ratios and determine the relationship between independent and dependent variables. P < .05 was considered statistically significant., Results: Of the 960 participants, 693 (72.1%) reported that their child had 1 or more untreated dental decay. The children of uneducated parents were 1.6-fold more likely to have 1 or more untreated dental decay (adjusted odds ratio [AOR], 1.66; 95% CI, 0.74-3.73; P < .001). The children of unemployed parents were 4.3-fold more likely to have a financial burden for a child dental visit (AOR, 4.34; 95% CI, 2.73-6.89; P < .001). Parents from a rural area were 26.3-fold more likely to have spent a lag period of over 2 years since their child's last dental visit (AOR, 26.34; 95% CI, 7.48-92.79; P < .001). Nursery-level children were 5.4-fold more likely to need immediate care (AOR, 5.38; 95% CI, 3.01-9.60; P < .001)., Conclusions: The present study demonstrated a very high prevalence of 1 or more untreated dental decay in our cohort. Children of rural areas, uneducated, unemployed, widow/divorced, low- and middle-income parents and nursery school children were linked to poorly predictive outcomes of child oral health during the pandemic., Competing Interests: Conflict of interest None disclosed., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)