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One-pot reaction between dialkyl acetylendicarboxylates and different hydrazide acids in the presence of triphenylphosphine leds to 1,3,5-substituted-1H-pyrazoles derivatives in excellent yields. In the absence of triphenylphosphine, dialkyl acetylenedicarboxylate adds to hydrazide acids to produce dialkyl 2-(arylhydrazono)succinates were obtained in good yields.

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Three algorithms of first-order reliability method (FORM) using steepest descent search direction are compared to evaluate the reliability index of structural steel problems which are designed by the Iranian National Building code. The FORM formula is modified based on a dynamic step size which is computed based on the merit functions named modified Hasofer-Lind and Rackwitz-Fiessler (MHL-RF) method. The efficiency of the gradient, HL-RF, and MHL-RF method was compared for a bar structure under tensile capacity, a multispan beam under bending capacity, a connection under tension load, and a column under axial force. The results illustrated that the MHL-RF method is more efficient than the HL-RF and gradient method. The designed steel components by the Iranian National Building code showed good confidence levels with the reliability index in the range from 2.5 to 3.0.