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Early this year (CORROSION TECHNOLOGY, March issue) we published the first part of a paper presented before the American Petroleum Institute's Refining Division and also the National Institute of Corrosion Engineers, describing the different forms of hydrogen damage and the prevention steps that were taken at the new fluid catalytic cracking unit of the Richfield Oil Corporation. At that time we announced that we hoped to publish more of this interesting paper, brought up to date. This, then, completes the work of Messrs. Neumaier and Schillmoller and describes protective steps that have been taken at the fluid unit gas plant, the evaluation of these steps, monitoring and the use of organic inhibitors.

Efforts to avoid low‐temperature hydrogen attack at a new fluid catalytic cracking unit of the Richfield Oil Corporation, Wilmington, Calif., have been successful as a result of corrosion prevention in the design stage and corrosion control during operation. When the unit was shut down recently after more than a year of successful and continuous operation it was found to be in excellent condition. The following is the first half of a paper presented before the American Petroleum Institute's Refining Division last year and before the National Institute of Corrosion Engineers' Annual Meeting this year. The authors describe the different forms of hydrogen damage and the prevention steps that were taken. Preliminary evaluation by hydrogen probes, painted‐can tests and chemical analyses were employed to detect any hydrogen penetration taking place before the routine shut‐down enabled

Resistance to hydrogen embrittlement. Since cathodic protection is quite necessary and actually extensively applied for the electrochemical control of corrosion of immersed steel structures, adequate consideration must be given to the several deleterious effects of hydrogen (commonly included in the term ‘hydrogen embrittlement’) from overprotection.

Four thermal spray coatings were subjected to high temperature corrosive environments of oil‐fired boiler conditions to compare their corrosion protection under simulated conditions. The coatings included FeCrAl, Tafaloy 45CT, which were arc‐sprayed, 50Ni‐50Cr and Cr₃C₂‐NiCr, which were coated by high velocity oxy fuel spray (HVOF) method.

The coating substrates used were SA213TP 347H, SA213 T11 and SA213 T22 alloys that are widely used as boiler tube materials. Specimens were covered with a synthetic ash mixture of 70 per cent V₂O₅‐20 per cent Na₂SO₄‐10 per cent NaCl and exposed to 550°C and 650^oC°for 192 h (6 cycles). After high temperature corrosion tests, weight change curves were obtained; specimens were examined by metallographical techniques, scanning electron microscopy and EDX analyses.

Salt deposits attacked steels and coatings during the exposure. The corrosion rates were strongly affected by the composition of the scale formed adjacent to the steels and coatings surfaces. Austenitic steel was only bare material that experienced uniform corrosion in the tests. Ferritic steels were primarily attacked by grain boundary corrosion. Thermally sprayed coatings were mainly attached through oxides and voids at splat boundaries. FeCrAl and 50Ni‐50Cr were prone to spalling. Tafaloy 45CT is also a promising method for producing homogenous coatings. Cr₃C₂‐NiCr 80/20 coating remained mostly intact.

This paper provides useful information about corrosion behaviours of four coatings used for common boiler tubes. It shows with a practical explanation how the bare material and coatings react in corrosion simulated environments.

Considers the advantages of highly alloyed stainless steel such as duplex stainless steels or nickel‐based alloys in highly corrosive environments. Looks at corrosion rates for alloys in acetic acid and presents results of tests on the influence of contaminants in the acid. Gives practical applications. Concludes that duplex stainless steels demonstrate higher corrosion resistance than austenitic stainless steels and are often comparable to nickel base alloys.

This study analyzes the mediating effect of emotional exhaustion between certain job demands (workload, role conflict, and influence at work) and employees' work attitudes (affective commitment and turnover intention) in public healthcare. Furthermore, it analyzes the moderating effect of possibilities for development and the degree of freedom at work between the above-mentioned job demands and emotional exhaustion.

A total of 512 healthcare professionals participated in the study. The data were analyzed using structural equation modeling and a hierarchical multiple regression analysis.

The results show that emotional exhaustion fully mediates the relationship between job demands (workload and role conflict) and work attitudes (affective commitment and turnover intention). Moreover, the possibilities for development and degree of freedom at work moderate the relationship between role conflict and emotional exhaustion.

Strategies should be designed to prevent employees from becoming emotionally exhausted and lead them to feel more motivated, which results in a more effective public healthcare service.

This study stresses the importance of analyzing the role of emotional exhaustion in the public healthcare context. It demonstrates the mediating role of this variable between several antecedents and consequences, and it analyzes whether other relevant variables can moderate the negative effects of emotional exhaustion.

The nature of public healthcare highlights not only the need of understanding the role of emotional exhaustion in the relationship between employees’ job demands and desirable employees’ job attitudes, but also to adequate the combination of certain job resources and other organisational variables to moderate the employees’ feelings of emotional exhaustion. The paper aims to discuss this issue.

This viewpoint designs the theoretical approach that aims to understand the mediating role of emotional exhaustion among healthcare professionals and the capacity of certain variables to moderate it. The nature of the variables considered and the design of the theoretical model proposed highlights structural equation modelling as an optimal methodology to be used among a sample of European healthcare professionals.

Managers should be able to design strategies to mitigate, eliminate and prevent the causes of emotional exhaustion in public healthcare with the objective to improve the health and quality of life of healthcare professionals, and consequently the quality of the service provided to patients and their families.

This viewpoint highlights the importance of analysing the influence of employees’ emotional exhaustion on their attitudes in public healthcare. Direct relationships between emotional exhaustion and certain antecedents or consequences have been studied previously; however, studies analysing the mediating role of emotional exhaustion are very scarce and show mixed results. There are also few studies analysing the moderating role of certain job resources and other organisational variables in the relationships between employees’ job demands, employees’ emotional exhaustion and employees’ job attitudes.