Contribución a la morfología, taxonomía y ecología de la fauna de Quilópodos de Andalucía (Sierra de Grazalema y Los Alcornocales), España

To increase our knowledge of the chilopod fauna of some poorly investigated regions of southern Spain, we arranged a collecting trip to Andalusia with a specific concentration on the Sierra de Grazalema and Los Alcornocales. As a result of hand collections and sieving at 21 localities we found altogether 20 species, 4 of them being new for Andalusia: Cryptops trisulcatus Brölemann, 1902; Algerophilus hispanicus (Meinert, 1870); Stigmatogaster superba (Meinert, 1870) and Henia vesuviana (Newport, 1845). For each of the species, records notes on general distribution, morphology and ecology are given. Taxonomic problems are discussed in relation to literature records.Con el fin de aumentar el conocimiento de la fauna de quilópodos de algunas regiones poco investigadas de España meridional, organizamos un viaje de recolección a Andalucía, dirigido a la Sierra de Grazalema y Los Alcornales. El resultado de colectas manuales y cribado en 21 localidades fue un total de 20 especies, 4 de las cuales son nuevas citas para Andalucía: Cryptops trisulcatus Brölemann, 1902; Algerophilus hispanicus (Meinert, 1870); Stigmatogaster superba (Meinert, 1870) y Henia vesuviana (Newport, 1845). Para cada especie se dan comentarios sobre su distribución general, morfología y ecología. Se discuten los problemas taxonómicos en relación con las citas encontradas en la literatura

Strengthening mechanisms in thermomechanically processed NbTi-microalloyed steel

The effect of deformation temperature on microstructure and mechanical properties was investigated for thermomechanically processed NbTi-microalloyed steel with ferrite-pearlite microstructure. With a decrease in the finish deformation temperature at 1348 K to 1098 K (1075 °C to 825 °C) temperature range, the ambient temperature yield stress did not vary significantly, work hardening rate decreased, ultimate tensile strength decreased, and elongation to failure increased. These variations in mechanical properties were correlated to the variations in microstructural parameters (such as ferrite grain size, solid solution concentrations, precipitate number density and dislocation density). Calculations based on the measured microstructural parameters suggested the grain refinement, solid solution strengthening, precipitation strengthening, and work hardening contributed up to 32 pct, up to 48 pct, up to 25 pct, and less than 3 pct to the yield stress, respectively. With a decrease in the finish deformation temperature, both the grain size strengthening and solid solution strengthening increased, the precipitation strengthening decreased, and the work hardening contribution did not vary significantly