A nearby supernova (SN) explosion in the past can be confirmed by the detection of radioisotopes on Earth that were produced and ejected by the SN. We have now measured a well resolved time profile of the 60Fe concentration in a deep-sea ferromanganese crust and found a highly significant increase 2.8 Myr ago. The amount of 60Fe is compatible with the deposition of ejecta from a SN at a distanc...

  Three different materials (aluminum, ferro -silicon and silicon) were used as antioxidants in order to prevent the decarburization process and to keep and/or increase the final properties in MgO-C refractories. Their effects were compared by measuring the physical and mechanical properties as well as oxidation and the resultant phases and microstructures, in the temperature range of 200-1600 ...

O sistema de degradação utilizando ferro metálico e peróxido de hidrogênio (reação de Fenton) foi empregado para a degradação do herbicida diurom. Visando obter as melhores condições de degradação, foram otimizados parâmetros que influenciam no processo, como pH, concentração de peróxido de hidrogênio (H 2 O 2 ) e quantidade de ferro. A degradação do herbicida foi acompanhada por cromatografia ...

Exiguobacterium sp. strain JLM-2 is a thermophilic bacterium isolated from deep-sea ferromanganese (FeMn) nodules. The estimated genome of this strain is 2.9 Mb, with a G+C content of 48.32%. It has a novel circular 15,570-bp plasmid. The draft genome sequence may provide useful information about Mn-microbe interactions and the genetic basis for tolerance to environment stresses.

The apparent molal adiabatic compressibilities of ferri- and ferrocytochrome c have been determined from measurements of density and sound velocity. The values found were +2.99 X 10(-8) and -2.40 X 10(-8) cm5 mol-1 dyne-1 for the ferri and ferro forms, respectively. Experiments were performed on identical solutions containing either the oxidized or reduced form of protein. Solutions of ferricyt...

O alcóxido heterometálico [FeCl{Ti 2 (OPr) 9 }] (1) foi utilizado como um precursor de fonte única para a preparação de óxidos de Fe/Ti sob atmosfera inerte. Três procedimentos sintéticos distintos foram adotados no processamento de 1, com o emprego de soluções aquosas ácidas (HNO 3 ou HCl), ou na ausência de ácido mineral. Os produtos foram caracterizados por difratometria de raios X (pó), mic...

The Colorado potato beetle [Leptinotarsa decemlineata (Say); Coleoptera: Chrysomelidae] is a significant pest of potatoes in North America and Eurasia and can cause severe defoliation and yield loss (Ferro 1985; Weber and Ferro 1994b). Managing the Colorado potato beetle with intensive pesticide applications has led to resistant populations (Forgash 1985; Ioannidis et al. 1991; Stewart et al. 1...

In the present study, Thermo-Reactive Deposition method (TRD) in a molten bath was used to form niobium carbide coating on AISI L2 steel. The coating was formed in five different composition of borax (Na2B4O7), boric acid (B2O3), and ferro-niobium. For all of the five compositions of molten bath, niobium carbide coating treatment was carried out at 1173 K, 1273 K, and 1373 K for 2, 4 and 8 hour...

Despite the abundant evidence for the enrichment of phosphorus during the petrogenesis of natural ferro-basalts, the effect of phosphorus on the physical properties of these melts is poorly understood. The effects of phosphorus on the viscosity, density and redox ratio of a ferro-basaltic melt have been determined experimentally. The viscosity measurements were obtained using the concentric cyl...

First-principles study is attempted to investigate L10-disorder phase equilibrium in Fe–Pt system. The present study consists of electronic structure total energy calculations by FLAPW for the ground state and statistical mechanics calculations by Cluster Variation Method for finite temperatures. It is revealed that the magnetism plays a crucial role in the phase stability. The spin polarized F...