Hexagonal close-packed (hcp) iron carbides play an important role in steel processing and in steel products. The recent discovery of novel ultrafine (2-5 nm) iron carbide (ε'-Fe2+xC) precipitates in TRIP steel sheds a new light on the hcp family of carbides. Here we present a first-principles study on the relative stability, and the electronic, magnetic properties of the ε'-Fe2C phases. Differe...

iron deficiency in soil reduces the quality of durum wheat leading to fe deficiency in human. thus, this experiment investigated the effects of foliar application of nano-iron oxide (2 and 4 g l-1), iron chelate (edta), (4 and 8 g l-1), iron sulfate (4 and 8 g l-1), and the control on grain yield and quality, yield components, chlorophyll and carotenoids contents, peroxidase (pox), catalase (ca...

The mechanical behavior of bicrystalline aluminum nano-pillars under uniaxial compression reveals size effects, a stochastic stress– strain signature, and strain hardening. Pillar diameters range from 400 nm to 2 lm and contain a single, non-sigma high angle grain boundary oriented parallel to the pillar axes. Our results indicate that these bicrystalline pillars are characterized by intermitte...

BACKGROUND Ultrafine particles (UFP) may contribute to the cardiovascular effects of particulate air pollution, partly because of their relatively efficient alveolar deposition. OBJECTIVE In this study, we assessed associations between blood pressure and short-term exposure to air pollution in a population of schoolchildren. METHODS In 130 children (6-12 years of age), blood pressure was de...

Accumulative roll-bonding process (ARB) is an important severe plastic deformation technique for production of the ultrafine grained, nanostructured and nanocomposite materials in the form of plates and sheets. In the present work, this process used for manufacturing Al/SiO 2 nanocomposites by using Aluminum 1050 alloy sheets and nano sized SiO 2 particles, at ambient temperature. After 8 cycle...

True stress (·)­true strain (3⁄4) relationships until just before fracture, i.e., the plastic deformation limit, were estimated by the stepwise tensile test and the Bridgman equation for various metals and alloys with different crystal structures. The estimated ·­3⁄4 relationships were different from the nominal stress­strain curves including the conventional tensile properties. In the relation...

Grain refinement can make conventional metals several times stronger, but this comes at dramatic loss of ductility. Here we report a heterogeneous lamella structure in Ti produced by asymmetric rolling and partial recrystallization that can produce an unprecedented property combination: as strong as ultrafine-grained metal and at the same time as ductile as conventional coarse-grained metal. It...

Recent epidemiological evidence strongly suggests that ambient-particle-associated acidity is more closely correlated with total mortality and hospital admissions for respiratory disease than indices of total particulate mass. In addition, evidence is accumulating to support the hypothesis that the number of ultrafine (d < or = 200 nm) acid particles, rather than ambient mass, is an important d...