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ne of the most important problems in our society today is the lack of protein and fiber in the diet, so enriching snacks with fiber and protein can produce products with high nutritional value and low in calories, fat and cholesterol. Due to the popularity and high consumption of extruded products among the general public, including children and adolescents, it is very important to improve the nutritional properties of these products. Accordingly, in this study, some characteristics of snacks containing starch (40 to 76%), wheat bran (zero to 30%) and moisture (14 to 20%) were investigated. Also, wheat gluten (10%) was added to all samples and the prepared mixtures were extruded at a temperature of 140 °C at a helical speed of 150 rpm. With increasing moisture and bran, water absorption index, water dissolution index first increases and then decreases, and with increasing moisture and bran, particle density, actual density and hardness increase, and with increasing starch, expansion coefficient and water absorption index, water dissolution index And the index L* increases and the particle density and the actual density decrease. With increasing humidity, L* index increases and with increasing bran decreases. With increasing humidity, the coefficient of expansion first increases and then decreases, but with increasing bran, the coefficient of expansion decreases. According to the obtained results, the use of 13% wheat bran, 61% wheat starch and 16% moisture of the input feed, produces a sample of good quality. [ABSTRACT FROM AUTHOR]

Background and Objective: Perforated panels are one of the most common resonant absorbers for sound control. These types of absorbers are widely used due to their adjustable mechanical properties and ease of processing. This study was conducted to investigate the acoustic properties of non-flat perforated panels in oblique angle and diffusion field using both numerical and experimental methods. Materials and Methods: To investigate the effect of surface shape on the performance of the perforated panel, three non-flat shapes were considered for the perforated panel and their absorption performance was compared with the usual shape of the perforated panel (i.e., flat) using the numerical method. Initially, the most appropriate shape was determined in terms of absorption coefficient. Afterward, the desired shape was constructed in the dimensions approved by the ISO 354 and subjected to a random incidence absorption coefficient test in the reverberation chamber. Results: The results of numerical simulation indicated that the shapes defined in this research all could improve the absorption coefficient at the middle and high frequencies. Moreover, the shape C showed a higher absorption coefficient at the lower frequencies than the flat and the two defined shapes. Based on the measurement of a random incidence absorption coefficient, the highest absorption coefficient was obtained at a frequency of 160 Hz with a value of 0.77. These conditions were implemented in a numerical environment and the random incidence absorption coefficient was calculated according to the existing relationships. Conclusion: It can be concluded that surface shape is effective in improving the absorption performance of these types of adsorbents. The comparison of numerical and laboratory results showed the acceptable agreement of these two methods and the numerical method is capable of predicting this quantity with good accuracy. [ABSTRACT FROM AUTHOR]

The intensity of sound in most industries and processes is a disturbing factor. Sound absorbers are a means of reducing noise. There are various types of sound absorbers with different designs and materials, but sound absorbers that can have a high absorption coefficient will be effective. The design of the manger sponge with fractal structure will be a good solution to this problem. Various factors such as composition type, step, and frequency affect this adsorbent. In this research, each of these factors was investigated and analyzed. The effects of the absorption coefficient and changes in sound level influenced by composition type, step and frequency factors were investigated and analyzed. Investigation of the step factor revealed that the amount of absorption coefficient in step 2 had better results compared to the step 1. The absorption coefficient in steps 1 and 2 were 0.3 and 0.38, respectively. Among the effective factors on the amount of absorption coefficient of manger sponge, the composition type was more effective. The results showed that the adsorbent with harder texture has a lower absorption coefficient and the adsorbent with a lighter texture has a higher absorption coefficient. Among the composition type used for this adsorbent, the sponge has a maximum absorption coefficient of 0.4 and MDF has a minimum absorption coefficient of 0.3. [ABSTRACT FROM AUTHOR]