Showing 3 results for Kord
Dr Ali Darehkordi, Mr Mohammad Sadegh Hosseini,
Volume 9, Issue 3 (september 2012)
Abstract
Montmorillonite modified is an efficient environmental friendly catalyst under one-pot-three-component synthesis of 3,4-dihydropyrimidine-2(1H) ones. The preparation was performed with an aldehyde, 1,3-dicarbonyl compounds, urea or thiourea under solvent-free conditions. In comparison with the other methods of Biginelli reaction, this new method has short reaction time inexpensive catalyst and in addition excellent yields were obtained.
H. Nosraty, M. Tehrani-Dehkordi, M. M. Shokrieh, G. Minak,
Volume 12, Issue 1 (march 2015 2015)
Abstract
In this study, the tensile and compressive behaviors of pure and hybrid composite laminates reinforced by
basalt–nylon bi-woven intra-ply fabrics were experimentally investigated. Epoxy resin was used as the matrix material.
The purpose of using this hybrid composite is to obtain superior characteristics by using the good strength property
of basalt fiber with the excellent toughness of nylon fiber. Five different types of woven fabric were used as
reinforcement with different volume percentages of nylon (0%, 25%, 33.3%, 50% and 100%). The effects of
nylon/basalt fiber content on tensile and compressive parameters were studied. In addition, the after failure visual
inspection and scanning electron microscopy (SEM) analysis was used to determine the extent and type of damage on
tested specimens. The results indicate that the tensile and compressive performances of these composites are strongly
affected by the nylon/basalt fiber content. Also, with a proper choice of fiber content, the nylon/basalt hybrid
composites can achieve mechanical properties comparable with the pure ones. The stress–strain curves, after failure
visual inspection and SEM analysis of tested specimens reveal that hybridization can prevent catastrophic and
complete failure. In hybrid composites, the basalt and nylon fibers cannot reach their maximum strength at the same
time and the progressive failure of the various fibers therefore occurred
S. Kord, M. H. Siadati, M. Alipour, H. Amiri, P.g. Koppad, A. C. Gowda,
Volume 15, Issue 4 (December 2018)
Abstract
The effects of rare earth element, erbium (Er) additions on the microstructure and mechanical properties of Al-15Zn-2.5Mg-2.5Cu alloy have been investigated. This new high strength alloy with erbium additions (0.5, 1.0, 1.5 and 2.0 wt%) was synthesized by liquid metallurgy route followed by hot extrusion. Microstructural characterization was performed using scanning electron microscope and electron probe microanalysis. Significant amount of grain refinement was observed with erbium addition in the hot extruded and heat treated alloy. Tensile test was performed to investigate the effect rare earth on mechanical behavior of alloy in as cast and hot extruded condition before and after T6 heat treatment. The combined effect of erbium addition, hot extrusion and heat treatment significantly enhanced the tensile strength of alloy (602 MPa) when compared to the as cast alloy without erbium addition (225 MPa). The strengthening of the alloy was attributed to grain refinement caused by erbium along with hot extrusion and formation of precipitates after T6 heat treatment. Fractograhic investigations revealed that the hot extruded alloy with erbium addition after heat treatment showed uniformly distributed deep dimples exhibiting ductile behavior.
