Influence of rice straw and calcium cyanamide on microbiological activity in two portuguese alluvial soils

Usaram-se dois aluviossolos portugueses (um arenoso outro franco) em experiências destinadas a estudar a influência da cianamida cálcica na actividade microbiológica, sob condições controladas. Ensaiaram-se modalidades com palha de arroz, palha de trigo e sem palha. Em algumas experiências utilizou-se para comparação um solo de loess colhido na Alemanha. A aplicação de palha conduziu a um aumento nítido da activi- dade da dehidrogenase nos dois solos, tendo-se verificado a superioridade da palha de trigo no solo arenoso. A influência da cianamida foi pequenainfo:eu-repo/semantics/publishedVersio

Suppression of Stochastic Domain Wall Pinning Through Control of Gilbert Damping

Finite temperature micromagnetic simulations were used to investigate the magnetisation structure, propagation dynamics and stochastic pinning of domain walls in rare earth-doped Ni80Fe20 nanowires. We first show how the increase of the Gilbert damping, caused by the inclusion rare-earth dopants such as holmium, acts to suppress Walker breakdown phenomena. This allows domain walls to maintain consistent magnetisation structures during propagation. We then employ finite temperature simulations to probe how this affects the stochastic pinning of domain walls at notch-shaped artificial defect sites. Our results indicate that the addition of even a few percent of holmium allows domain walls to pin with consistent and well-defined magnetisation configurations, thus suppressing dynamically-induced stochastic pinning/depinning phenomena. Together, these results demonstrate a powerful, materials science-based solution to the problems of stochastic domain wall pinning in soft ferromagnetic nanowires