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Spin-bonding is a method for fabrication of bilayer tubes based on flow-forming process. This new method is a process with high potential in production of seamless thin-walled tubes. Utilizing this process, aluminum tube (as the inner layer or clad layer) has been bonded into steel tube (as the outer layer) to fabricate tubular laminate composites. As important parameters for creating a suitable bond, effects of thickness reduction, initial aluminum thickness and strength on bonding strength were investigated. The bond strength was evaluated by peel test and the peeled surfaces were examined using scanning electron microscopy (SEM). The results indicated that thickness reduction has great influence on strength and quality of the bond. After a threshold reduction (about 35%) the bond strength increases rapidly with the amount of deformation, until it approaches the weaker metal strength, and samples fracture from the base metal in the peel test. Approaching the strength of the two metals and decreasing the initial thickness of the clad layer, with a high amount of deformation increased the bonding strength. Fracture surface images showed that the surface fraction of bonding area was increased when deformation increased. It was also increased with the reduction of the initial thickness of the clad layer and when the strength of the two layers approached each other. Additionally, distribution and shape of the fracture area changed from a disordered fibril structure to approximately straight area, with an increase in the deformation.

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Chlorpyrifos is widely used to control various insect pests on greenhouse cucumbers in Iran. In this study, the effects of the household processing such as washing, peeling, and refrigeration storage on the reduction of residue levels in cucumbers were investigated in different groups. Samples were collected at 1 hour to 14 days after application of chlorpyrifos and analyzed to determine the content of chlorpyrifos. Analysis was carried out by the QuEChERS method using GC-NPD. Residue levels in samples throughout a period of 14 days showed a gradual and significant (P< 0.05) decrease in contents of chlorpyrifos. The half-life (t_1/2) of chlorpyrifos applied to cucumbers was 1.9 days. Chlorpyrifos was detected in concentration ranges of 0.02-4.73 mg kg^-1. Household processing, such as washing, peeling and refrigeration storage, was effective in reducing the residue levels. Peeling was the most effective way to reduce residues in the cucumbers. Obtained results showed that a waiting period after chlorpyrifos application and household processing are required for safe consumption of cucumber.