This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens...This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens were heat treated to obtain hardness of 294, 445 and 595 HV200 (29, 45 and 55 HRC). Erosion tests were carried out at impingement angles from 20° to 90° and air drag pressures of 1.38, 2.07 and 2.76 bar (20, 30 and 40 psi). The main results are summarized as follows:(i) The harder material, the lower erosion;(ii) the maximum erosion rate is at 30°;(iii) Little difference in erosion rate at impact angle of 60° and 90° for a constant pressure tested regardless of the hardness level;(iv) As the pressure increases, so does the erosion rate, being more sensitive for low impact angles. Finally, a differential form of the general erosion equation is applied on a practical core-making case to evaluate the erosion rate of the H13 steel at 30° and 90° impingement angles.展开更多
A new putative transposon was identified in the tobacco budworm, Helio- this virescens. This transposon was characterized as a full length CORE-SINE （65 bp of ＂CORE＂ core specific nucleotide short interspersed elem...A new putative transposon was identified in the tobacco budworm, Helio- this virescens. This transposon was characterized as a full length CORE-SINE （65 bp of ＂CORE＂ core specific nucleotide short interspersed elements） that resembled sequences from three other lepidopterans and humans. In particular, the A-box and B-box regions of this sequence most closely conformed to the signature of CORE-SINEs from widely divergent species. This CORE-SINE was present as a polymorphism in a hypervariable region of the gene hscp, which is the target of pyrethroid insecticides and other xenobiotics in the nerve axon. We described this new putative transposon as Noct-1 due to its presence in a noctuid moth. This is the first description of a full-length CORE-SINE with the A-box, B-box, target site duplication, and candidate core domain from an insect.展开更多
基金financially supported by NEMAK S.A. and Industria Meccanica Bassi Luigi&Co
文摘This paper presents the erosion results of the AISI H13 steel impinged by resin-bonded silica sand, using a testing rig that closely simulates the real blowing conditions during industrial core-making. Steel specimens were heat treated to obtain hardness of 294, 445 and 595 HV200 (29, 45 and 55 HRC). Erosion tests were carried out at impingement angles from 20° to 90° and air drag pressures of 1.38, 2.07 and 2.76 bar (20, 30 and 40 psi). The main results are summarized as follows:(i) The harder material, the lower erosion;(ii) the maximum erosion rate is at 30°;(iii) Little difference in erosion rate at impact angle of 60° and 90° for a constant pressure tested regardless of the hardness level;(iv) As the pressure increases, so does the erosion rate, being more sensitive for low impact angles. Finally, a differential form of the general erosion equation is applied on a practical core-making case to evaluate the erosion rate of the H13 steel at 30° and 90° impingement angles.
文摘A new putative transposon was identified in the tobacco budworm, Helio- this virescens. This transposon was characterized as a full length CORE-SINE （65 bp of ＂CORE＂ core specific nucleotide short interspersed elements） that resembled sequences from three other lepidopterans and humans. In particular, the A-box and B-box regions of this sequence most closely conformed to the signature of CORE-SINEs from widely divergent species. This CORE-SINE was present as a polymorphism in a hypervariable region of the gene hscp, which is the target of pyrethroid insecticides and other xenobiotics in the nerve axon. We described this new putative transposon as Noct-1 due to its presence in a noctuid moth. This is the first description of a full-length CORE-SINE with the A-box, B-box, target site duplication, and candidate core domain from an insect.
