Durability of Metal-Composite Friction Spot Joints under Environmental Conditions

The current paper investigates the durability of the single-lap shear aluminum-composite friction spot joints and their behavior under harsh accelerated aging as well as natural weathering conditions. Four aluminum surface pre-treatments were selected to be performed on the joints based on previous investigations; these were sandblasting (SB), conversion coating (CC), phosphoric acid anodizing (PAA), and PAA with a subsequent application of primer (PAA-P). Most of the pre-treated specimens retained approximately 90% of their initial as-joined strength after accelerated aging experiments. In the case of the PAA pre-treatment, the joint showed a lower retained strength of about 60%. This was explained based on the penetration of humidity into the fine pores of the PAA pre-treated aluminum, reducing the adhesion between the aluminum and composite. Moreover, friction spot joints produced with three selected surface pre-treatments were held under outside natural weathering conditions for one year. PAA-P surface pre-treated specimens demonstrated the best performance with a retained strength of more than 80% after one year. It is believed that tight adhesion and chemical bonding reduced the penetration of humidity at the interface between the joining parts

Developing the Moral Distress Scale in the Population of Iranian Nurses

"n Objective: "n To develop "moral distress questionnaire" and validate it in a sample of Iranian registered nurses. "nMethod: 26 registered nurses and 10 professionals attended focused group discussion (FGD) sessions and the acquired qualitative data was analyzed by Jameton scale analysis. "nResults: Attitudes and definitions of nurses working in private and governmental hospitals of two medical universities in Tehran revealed moral distress in nurses, and also showed that moral distress influenced the sample population. Results of the present study were concordant with Jameton's model although some background and conceptual differences were observed. "nConclusion: Design and conduction of some interventions to help nurses cope with the moral distress caused by their occupation seems necessary