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bstract The average behavior of composite material like masonry can be described in terms of the relation average stresses and strains (macro model) if the material is assumed to be homogeneous. The average stress-strain relationship can be determined generally using two approaches. A possible approach is experimental investigation from the available experimental data. Another approach, adopted in this resedrch, is to develop a linear homogenization technique, which describes the behavior of the masonry from the geometry and the behavior of the representative basic cell. In this research, the elastic properties of a basic cell in masonry with a periodic arrangement of blocks were obtained based on a local stress field approach (micro-modeling of the mortar and blocks).Two different methods were used for computing the equivalent orthotropic elastic properties of the basic cell as a continuum, the approximate energy method (a closed form solution) and the finite element based method. The finite element method was used to approximately find the orthotropic yield curves of the homogenous element. The similarity of the general behavior of these gied curves with regard to the experimental facts was considerable.

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Research on microstructure of main engineering materials revealed that some of these materials exhibit similar microstructure patterns at different length scales. Since these patterns are replicated at different length scales the whole microstructure can be viewed as a set of periodic substructures. Homogenization technique for periodic microstructures has found many applications in simulation of composite materials by considering the geometry of fibers distribution. In this study a homogenization technique for periodic microstructures is developed. In this generalization a multi-step homogenization is being used. In each step of homogenization the geometry which is coincident with the true microstructure is produced to maintain the properties of the mechanical properties of the related cell. By using the presented method effect of size and grading of each of reinforcing phases and the interaction between fibers is taken into account. The results of the presented theory are compared with the existing experimental data on the particle reinforced composites. Good agreement between the presented theory and experimental data is found.

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The application of woven fabrics in composites manufacturing has been increased because of their special mechanical behavior. Due to the complexity of modeling and simulation of these composites, in this research a micromechanics based analytical model has been developed to predict the elastic properties of woven fabric composites. The present model is simple to use and has a high accuracy in predicting the elastic properties of woven fabric composites. One of the most important effective factors on the modeling accuracy is utilizing a proper homogenization method. Therefore, a new homogenization method has been developed by using a laminate analogy based method for the woven fabric composites. The proposed homogenization method is a multi-scale homogenization procedure. This model divides the representative volume element to several sub-elements, in a way that the combination of the sub-elements can be considered as a laminated composite. To determine the mechanical properties of laminates, instead of using an iso-strain assumption, the assumptions of constant in-plane strains and constant out of plane stress have been considered. Then, the proposed homogenization model has been combined with a micromechanical model to propose the new micromechanical model. The applied assumptions improve the prediction of mechanical properties of woven fabrics composites, especially the out of plane elastic properties. The proposed model has been evaluated by comparing the predicted results with four available experimental results available in the literature, and the accuracy of the present model has been shown.

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In this research, the effects of Konjac gum (0.2-0.6%), Fat content (18-25%) and Homogenization pressure (100-200 bar) on rheological properties of low fat cream were investigated. The results of the back extrusion test indicated that increasing konjac gum, fat content and homogenization pressure, significantly increased hardness, consistency and adhesiveness. The simultaneous increasing of homogenization pressure and fat content also led to increasing adhesiveness of the samples, which showed their synergistic effect of them on the adhesiveness. The results of the steady shear test showed that the flow behavior index (n) of all samples was less than one which indicates a shear thinning behavior (pseudoplastic) of all samples. Also increasing fat content, significantly decreased the flow behavior index of the samples and increased the consistency. konjac gum and homogenization pressure had no significant effect on the flow behavior. The optimum processing conditions for producing low fat cream with the high hardness, consistency, consistency coefficient and low flow behavior index for response variables were 146/51 bar homogenization pressure،18/01% Fat content and 0.59% konjac gum.

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In this research, a type of cream was produced according to the standard method with different percentages of fat and different pressures of homogenization. Five treatments were prepared as follows: T₁: 25% of fat and homogenization pressure was 100 bar, T₂: 30% of fat and homogenization pressure was 100 bar, T₃: 25% of fat and homogenization pressure was 200 bar, T₄: 30% of fat and homogenization pressure was 200 bar and T₅ as a control sample: 25% of fat and homogenization pressure was 150 bar. Completely randomized design was used as a design experiment and experiments were carried out at 3 replications. The results showed that treatments with higher fat% had higher acidity(dornic) and lower pH, and treatment with less fat and homogenization pressure had higher dry matter and treatments with higher homogenization pressure showed more syneresis%. The results obtained from rheological properties, showed that with the increase of fat percentage and decrease of homogenization pressure, the rheological indices of G´and G˝ increased and simultaneously with the increase of G´, the viscosity also increased, and the loss tanα decreased when G´ increased. The colorimetric test showed that samples with more fat have more yellowness than other treatments Sensory evaluation showed that samples with higher fat and higher homogenization pressure were more accepted by panelists. according to above mentioned, T₄ with 30 percentages of fat and 200 bar of homogenization pressure was the best treatments among others.