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This paper reports numerical simulation of deformation and crack growth in steel pipes under internal moving pressure. A systematic method was developed for the determination of the detonation driven fracture problem parameters. The simulations were performed on steel gas pipes. Explosive PETN cords with detonation speed more than 7000 meters per second were used for creating a confined fracture on the pipe shells. Two finite element models were created for calculation of internal moving pressure parameters and simulation of crack growth. The first model was an Eulerian finite element model that was created for calculation of moving pressure parameters that were applied to tube shell. The second model was a Lagrangian finite element model that was created for ductile crack growth simulation with cohesive elements and element deletion methods. The model used the moving pressure parameters, elastoplastic rate dependent and dynamic cohesive element fracture parameters for simulation of deformation and crack growth. In the next step, the results of finite element model were verified using analytical models. The finite element model predicted the axial crack growth length with less than 7 percent error and crack arrest point with less than 10 percent error from experimental results.

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The unique properties of camel milk, qualify this product to be used as a nutraceutical. In this study, functional synbiotic yogurt made from camel milk has been investigated in three levels of fat (0, 2.5 and 5% (w/v)). Probiotic bacteria (Streptococcus thermophilus, Lactobacilus delbrueckii and ssp. bulgaricus.) and β-glucan (prebiotic agent) were added in three levels of concentration (0.5, 1 and 1.5 % (v/v)) and (0, 1 and 2% (w/v)), respectively. The physicochemical properties of the product and viability of probiotic bacteria were measured on the 0, 7th and 14th days. Beta-glucan, fat and storage time had significantly (P< 0.05) increasing effects on viscosity, Water-Holding Capacity (WHC) and the viability of probiotic bacteria. These parameters caused decrease in syneresis and pH of yogurt. It was concluded that the addition of oat β-glucan to camel milk to make functional synbiotic yogurt could result in a product of acceptable physicochemical properties.