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A 27 day study was undertaken to evaluate the effects of aqueous extracts of Hypericumperforatum on hemato-serological parameters and survival of rainbow trout (Oncorhynchusmikiss) under thermal stress (20 ± 2 ◦C). A total of 360 rainbow trout (97.2 ± 1.6g) were divided randomly into four groups and  immersed in different concentrations (0, 250, 500 and 750 ppm) (T0, T25, T50 and T75) of aqueous extracts of H. perforatum. The blood samples were collected on day 12 and 27 and hemato-serological parameters were determined. In stage 1, the total red blood cell, hemoglobin and hematocrit didn’t show a significant difference among controls and treatments but in stage 2, those parameters were significantly increased in T50 and T75 compared to T0 and T25.  The total white blood cell, lymphocytes, total protein, albumin, and total IgM showed a significant increase in treatments compared to control but the results in the neutrophils was opposit. The MCV and MCH didn’t significantly change in two stages but the MCHC of T75 were significantly higher than T0 and T25. The glucose of T50 and T75 were significantly lower than T0 and T25. The hepatic enzymes, ALT and AST of T75 significantly increased compared to other groups in stage2. The highest and lowest survival rates were observed in T50 and T0, respectively. Based on the results, it seems that Hypericumperforatum could control the effectsof stress and increase the survival rate of rainbow trout when exposed to chronic heat stress.

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Abstract- Gaseous detonation in tubes produces moving pressure-thermal waves. A gaseous detonation consists of a shock wave and a reaction zone that are tightly coupled. The speed, pressure, and temperature of the products of detonation depend on the type and amount of the initial mixture. The maximum pressure of mechanical wave caused by detonation can be as high as 20-30 times the ambient pressure and temperature of gas in detonation may exceed 2000°C. The mechanical shock waves can cause oscillating strains in the tube wall, which can be several times higher than the equivalent static strains. On the other hand, the passage of the heat wave produces thermal stresses in the tube wall. In the current study the resulting mechanical and thermal stresses have been assessed using numerical simulations. In practice, the mechanical and thermal displacements have been computed separately. Finally, the combined effects of mechanical and thermal stresses caused by gaseous detonation have been simulated.

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A homogenous 2D plate with simply support boundary conditions and local imperfection is assumed. The effect of nonlinear deformation with Reddy and marguerre plate model has been introduced. The effect of local imperfection in non-Linear vibration analysis with the effect of thermal and in-plane load has been investigated for the first time. The plate softening and hardening type with the effect of imperfection size is investigated. Flutter boundary of local imperfect plate with the effect of supersonic aerodynamic, thermal and mechanical load has been studied for the first time. First and third order piston theory aerodynamic (PTA) is employed to model supersonic aerodynamic loading. Equations of motion have been derived by the use of Hamilton’s principle and resultant nonlinear PDEs have been transformed into nonlinear ODEs via Galerkin’s method. Forth and fifth order rang-kutta numerical method has been used to solve ODEs and define panel behavior. Results show that, imperfection amplitude increase structural non-linear frequencie, and change plate softening type to hardening. Also, amplitude of plate vibration increase and flutter speed decrease continuously. Plate amplitude oscillation increase for small imperfection and decrease for larger imperfection versus flow speed.

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Interlaminar thermal stresses and boundary layer effect in thin laminated composite cylinders which are subjected to temperature change are studied. To this aim a laminated cross-ply composite cylinder with finite length which is subjected to thermal loading is modeled. The displacement based layerwise theory (LWT) is used for modeling the response of the composite cylinder in the thermal loading conditions. Using an appropriate displacement field and employing the LWT, the governing equations of the cylinder and the appropriate boundary conditions in the edges of the cylinder are derived with the principle of minimum total potential energy. An analytical solution is introduced for the governing equations and the solution is obtained for various boundary conditions. The numerical results are validated by comparison of the results of LWT with the predictions of the finite element method (FEM) and good agreements are seen. It is seen that the presented LW solution is efficient and accurate method for analysis the edge effect and interlaminar stresses in composite cylinders. The interlaminar thermal stresses and in-plane stresses in the Glass/Epoxy composite cylinder which are subjected to thermal loading are investigated for various boundary (edge) conditions. Cylinders with symmetric and asymmetric layer staking and free, simply and clamped boundary conditions are studied in the numerical results.

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Fire is one of the risks that the study of its effects on different structures is essential. Fire can lead to extensive social and economic damage. Furthermore, knowing the extent of damage to concrete under heat can also help designers in the strengthening of structures. Connections are one of the most sensitive areas in all structural frames, steel and concrete, affected by large forces during earthquakes and their performance has a very important effect on the structurechr('39')s response. For this purpose, it is important to study the behavior of different types of beam-column joints in different environmental conditions. However, experimental and numerical data on the behavior of RC beam-column joints under high temperature are not available. In addition, due to the special feature of beam-column joints, ie passing part of the longitudinal reinforcements of the beam outside the connection spring, in this study, the behavior of beam-column reinforced concrete joints under the influence of thermal stresses has been investigated. In this research, 9 numerical models of wide beam-column joints under post-earthquake fire were investigated. After validation of modeled specimens, parametric study was conducted. Parameters such as wide beam height, beam reinforcement area, concrete grade and percentage of passing bars through the column core were studied. Results showed that with increasing the height of the beam, the fire resistance of the structure increases. Also, with increasing rebar area and concrete strength, the structurechr('39')s fire resistance increases. In addition, by reducing the rebar passing through the column core, the fire resistance of the structure is reduced. There is one thing in common in all these matters; all joints begin to form plastic joints at a temperature of about 450°C, and this temperature in the joints is formed about 200 minutes after the start of the fire.

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In present study, the stress and strain distributions due to the radiant gradient in some radiant tube burners have been investigated. In the design of the burner, several outlet valves are mounted on the wall of the burner tube and the combustion-produced fluid is discharged by the outlets into the furnace. For this purpose, three cylindrical radiant tubes with the same length, diameter, thickness and material and difference in design of fluid outlets are modeled. To simulate the mechanical behavior of the pipes, after the geometric modeling and considering the pipe material and boundary conditions, ANSYS commercial software has been used. The boundary conditions for numerical solution are extracted from the results of the experimental tests. Due to the average fluid velocity within the radial tube, the fluid flow falls into the turbulent range. In order to obtain the stress-strain diagram of the tested alloy, the Ramberg-Osgood equation is used. Due to the solution of the fluid-solid interaction by ANSYS, the best design is concluded through the Von-Mises stress minimum values. Also, by removing the thermal load from the next load step, the residual stresses generated in the samples are calculated. To illustrate the accuracy of the solution, some specimens of the burner have been made and evaluated to verify the numerical solution.