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This study was designed and performed to evaluate the effect of using the active edible coating of sodium alginate containing different levels of rosemary extract on physicochemical and microbial properties of silver carp-chicken fillet mixed burger during storage. 5 treatments including uncoated burgers (control) with sodium alginate coating enriched with levels of 0, 0.5, 1 and 1.5% of rosemary extract were considered. Burgers were stored at -18 ° C for 3 months. Results showed that the use of sodium alginate coating significantly decreased the percentage of burger cooking drop. Enrichment of sodium alginate coating with different levels of rosemary extract improved its performance (P<0.05). The lowest total microbial count, psychrophilic bacteria count, TVN, PV and TBA were observed in coated burgers containing 1.5% of rosemary extract (P<0.05). There was no statistically significant difference in the performance of coatings containing levels of 1 and 1.5% of rosemary extract in decreasing TBA. Thus it is possible to use the active edible coating of sodium alginate containing 1.5% of rosemary extract to delay bacterial and oxidative spoilage of silver carp-chicken fillet burgers during a 3-month storage period at -18 ° C used.

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Evaluation of pressure oscillation of solid rocket motors in actual conditions requires static tests. These test have a large application in evaluation of motor various parameters effect on its operation. Using of these tests are very limited due to their high costs and so, evaluation of various parameters is nearly impossible. To solve this problem, sub scaled solid rocket motor must be designed. In this paper, designing process of space shuttle sub scaled solid boosters, called 1881, with scale 1:31 has been proposed. Space shuttle and ariane 5 boosters have been argued to modeling and simulation. Sub scaled motor modeling and design parameters using Buckingham’s Pi theorem and then, operation and dimensional properties have been presented. Three tests for evaluation of designed motor were done successfully and pressure and thrust history and its oscillations have been evaluated. Results show that for facility of fitting and reduction of test cost in subscale motors, using of Tan-Cu in throat instead of graphite and flange design of joints are very useful. Despite of using Buckingham’s Pi theorem in solid motor scaling, propellant chemistry and its burning rate are affected of Crawford bomb and real flow of combustion products and in many case, error correction between Crawford and motor data is inevitable. On the other hand, existence of empty volume in forward segments and others, plays an important role in pressure oscillations and after end of burning or reducing, oscillations will be uniform.

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