7075 aluminum alloy (AA7075) has been extensively used in the aerospace and defense industries owing to its supreme mechanical performance. As a promising platform fabricate metallic components with complex structures, selective laser melting (SLM) successful manufacturing alloys such as Al-Si-Mg. However, high-strength AA7075 is difficult be manufactured by SLM due tendencies toward hot cracki...

FIn this work, AlN/SiCN composite coatings were deposited by r.f.-reactive sputtering method using a facing target-type sputtering (FTS) apparatus with composite targets consisting of Al plate and SiC chips in a gaseous mixture of Ar and N2, and investigated their mechanical properties and microstructure. The indentation hardness (HIT ) of AlN/SiCN coatings prepared from composite targets consi...

The influence of the grain boundary (GB) specific area s GB on the appearance of ferromagnetism in Fe-doped ZnO has been analysed. A review of numerous research contributions from the literature on the origin of the ferromagnetic behaviour of Fe-doped ZnO is given. An empirical correlation has been found that the value of the specific grain boundary area s GB is the main factor controlling such...

a survey was carried out in five provinces of iran (kerman, sistan and baluchestan, hormozgan, khorasan and yazd) for the presence of alfalfa mosaic virus (amv) sero-types in alfalfa during 2002 to 2003. the number of samples collected was 250, represent-ing the diversity and geographical distribution of amv in these areas. diagnosis was car-ried out using polyclonal (pabs) and monoclonal (mabs...

background the search for novel antibiotics continues to be of immense importance in research programs around the world for pharmaceutical, industrial and agricultural applications. filamentous soil bacteria, belonging to the streptomyces genus, are widely used as an important biological tool for their ability to produce a wide range of novel secondary metabolites, such as “antibiotics”. object...

RESUMO Neste trabalho utilizou-se uma liga hipereutética Al-40wt%Cu para verificar a influência das variáveis de entrada taxa resfriamento (°C/min) e superaquecimento (°C), na variável saída microdureza (HV). As amostras foram vazadas em cadinhos cerâmica cobre um termopar acoplado à sistema aquisição dados mediu as taxas que 20°C/min 24°C/min, respectivamente. Avaliou-se dessas do 100°C 200°C ...

Wire and arc additive manufacturing cold metal transfer® enable the defect-free soldering of poorly weldable alloys, such as AA6061. Thin-walls have been successfully built with two deposition strategies that is either a back forth movement torch (alternate vectors) or repeating along one direction (unidirectional vectors). The obtained macro- micro-structures are highly dependent on WAAM proce...

background : in many jobs, individuals are exposed to thermal stress, and thus, evaluation of heat stress is necessary. this study was conducted with the purpose of investigating the relationship of perceptual strain index (pesi) with other heat indexes under hot laboratory conditions. methods: this empirical-experimental and cross-sectional study was performed in 5 different temperatures (21 º...