It is shown that a method for calculating unified total electron-ion recombination rates, incorporating both the radiative and dielectronic recombination processes, can be applied to substantially complex atomic systems where a large number of recombination channels need to be coupled in an ab initio manner. Calculations are carried out for the astrophysically important ion Fe III, and total an...

A coupled finite element (FE) method and meshless local Petrov-Galerkin (MLPG) method for analyzing two-dimensional potential problems is presented in this paper. The analysis domain is subdivided into two regions, a finite element (FE) region and a meshless (MM) region. A single weighted residual form is written for the entire domain. Independent trial and test functions are assumed in the FE ...

Surface and interface properties of Fe-Cr, Fe-Al, and Fe-Cr-Al are studied using Exact Muffin-Tin Orbitals and Monte Carlo methods and with x-ray photoelectron and Auger electron techniques. Surface composition is investigated as a function of oxidation (heating) time. Hard x ray photoelectron spectroscopy (HAXPES) is used to scan non destructively the compositions below the surface. It is foun...

We have studied the exchange anisotropy of ferromagnetic Fe films grown on antiferromagnetic FeF2 single crystals. The behavior of the hysteresis loops of the Fe above and below the Néel temperature TN of FeF2 indicates a 90° rotation of the ferromagnetic easy axis due to the antiferromagnetic ordering. By examining the Fe hysteresis loops together with the FeF2 susceptibility behavior we infer...

Aerobic organisms are faced with a dilemma. Environmental iron is found primarily in the relatively inert Fe(III) form, whereas the more metabolically active ferrous form is a strong pro-oxidant. This conundrum is solved by the redox cycling of iron between Fe(III) and Fe(II) at every step in the iron metabolic pathway. As a transition metal ion, iron can be "metabolized" only by this redox cyc...

prenatal lead exposure could not only affect various organ systems of the mother, but also provide a plumbeous environment for the fetus and newborns, and may affect the fetus in a number of detrimental ways. the aim of this study was to adequately determine the interaction between these factors and risky behaviors such as smoking.data from nanjing maternity and child health care hospital surve...

We evaluated the inducibility of nitrate-dependent Fe(II)-EDTA oxidation (NDFO) in non-growth, chloramphenicol-amended, resting-cell suspensions of Dechloromonas sp. strain UWNR4 and Acidovorax sp. strain 2AN. Cells previously incubated with Fe(II)-EDTA oxidized ca. 6-fold more Fe(II)-EDTA than cells previously incubated with Fe(III)-EDTA. This is the first report of induction of NDFO by Fe(II).

We report the observation of symmetric fission in doubly charged Fe-S cluster anions, [Fe(4)S(4)X(4)](2-)-->2[Fe(2)S(2)X(2)](-) (X=Cl,Br), owing to both Coulomb repulsion and antiferromagnetic coupling. Photoelectron spectroscopy shows that both the parent and the fission fragments have similar electronic structures and confirms the inverted energy schemes due to the strong spin polarization of...

Iron-60 (t1/2= 2.62Myr) is a short-lived nuclide that can help constrain the astrophysical context of Solar System formation and date early Solar System events. A high abundance of Fe(Fe/Fe ≈ 4 × 10) was reported by in situ techniques in some chondrules from the LL3.00 Semarkona meteorite, which was taken as evidence that a supernova exploded in the vicinity of the birthplace of the Sun. Howeve...

In the presence of iron (Fe), dissolved organic matter (DOM) may bind considerable amounts of arsenic (As), through formation of Fe-bridged As-Fe-DOM complexes and surface complexation of As on DOM-stabilized Fe-colloids (collectively referred to as As-Fe-DOM complexation). However, direct (e.g., chromatographic and spectroscopic) evidence and fundamental kinetic and stability constants have be...