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The article investigated the impact of different cooling regimes on the response of both plain and fibre reinforced concrete (FRC) after heating. A total of 256 standard concrete cylinders of norma...

Semi-supported steel plate shear walls (SSPSWs) system has been attracted the attention of researchers' interest with maintaining positive performance and reducing defects in conventional steel plate shear walls, that including stress reduction in the main columns. In the current paper, the impact of thickness and type of infill plate materials (high-strength steel ASTM A572 with yield stress (YS) of 345?MPa, Medium-yield A36 steel with the YS of 245?MPa, Low-yield steel LPY100 with the YS of 100?MPa) on the loading capacity, energy absorption and behavior ratios (stiffness [K], behavior ratio [R], ductility ratio [?]) of SSPSWs are evaluated. For this purpose, 12 shear walls were modeled in the ABAQUS software. Results showed that the loading capacity and energy absorption of SSPSWs with ASTM A572 infill plate is more than other models and the ductility ratio of SSPSWs with LPY100 infill plate is higher than that of others. Therefore, for SSPSWs with infill plates type of ASTM572, A36, and LPY100 and with a thickness of 2?mm, the ductility ratios are 2.919768, 3.42301, and 5.117279, respectively.

Steel fiber reinforced concrete (SFRC) (an impact resistant material) has a good energy dissipation capacity and ductility through the developing of impact toughness and tensile strength. Due to la...

The antifungal activity of Streptomyces griseorubens E44G against Rhizoctonia solani, the causal agent of root rot disease of corn, was investigated. The mycelial growth of R. solani was inhibited by S. griseorubens E44G, indicating that it has an antifungal potential. The antagonist, S. griseorubens E44G, was detected to have proteolytic activity, using the method of casein hydrolysis. Moreover, the protease production was optimized under submerged conditions. The purification and precipitation of protease were achieved by ammonium sulphate and Sephadex G-100 gel filtration chromatography. Protease activity was detected spectrophotometrically based on the production of tyrosine. The molecular weight of the enzyme (35 kDa) was determined by sodium dodecyl sulphate polyacrylamide gel electrophoresis . The optimum activity of the enzyme was detected at pH 8.5 and 60 °C. The results indicated that the enzyme was thermostable and retained full activity even after 1 hour of incubation at 60 °C. The purified en...