Motivated by biomolecular computing, forbidding-enforcing systems (fe-systems) were first used to define classes of languages (fefamilies) based on boundary conditions. This paper presents a new model of fe-systems in which fe-systems define single languages (fe-languages) based on forbidden and enforced subwords. The paper characterizes wellknown languages by fe-systems, investigates the relat...

we evaluated the effect of fe/alumina catalyst contained different cadmium contents and two synthesis temperatures on producing carbon nanotubes by chemical vapor deposition of methane as a feedstock.  x-ray powder diffraction (xrd), n2 adsorption-desorption, scanning electron microscopy (sem), transmission electron microscopy (tem), raman spectroscopy and thermogravimetry analysis (tga) were u...

although cu and fe are immiscible under equilibrium conditions, they can form supersaturated solid solutions by mechanical alloying. in this paper, nano-structured of the metastable cu-fe phase containing 10, 15, 20 and 25% wt fe were synthesized by intensive ball milling for 15h, in order to achieve a solid solution of fe in cu. the phase composition, dissolution of the fe atoms into the cu ma...

Shewanella putrefaciens, a heterotrophic member of the gamma-proteobacteria is capable of respiring anaerobically on Fe(III) as the sole terminal electron acceptor (TEA). Recent genetic and biochemical studies have indicated that anaerobic Fe(III) respiration by S. putrefaciens requires outer-membrane targeted secretion of respiration-linked Fe(III) reductases. Thus, the availability of Fe(III)...

A study was conducted to investigate Fe requirements of broiler breeders. One-hundred-fifty-six Cobb 500 broiler breeder hens were individually placed in electrostatically painted cages at 22 weeks. The study was composed of an adaptation phase, in which hens were fed corn-soy-wheat bran diets until 35 wks. An Fe deficient mash diet (24.6 ppm Fe) was provided from 35 to 46 wk in order to induce...

Fe deficiency compromises both human health and plant productivity. Thus, it is important to understand plant Fe acquisition strategies for the development of crop plants which are more Fe-efficient under Fe-limited conditions, such as alkaline soils, and have higher Fe density in their edible tissues. Root secretion of phenolic compounds has long been hypothesized to be a component of the redu...

Copper abundances are presented for 40 red-giant members of the massive Galactic globular cluster ω Centauri, as well as 15 red-giant members of the globular clusters NGC288, NGC362, NGC3201, NGC6752, and M4 (NGC6121). The spectra are of relatively high spectral-resolution and signal-to-noise. Using these abundances, plus published literature values for field stars, the abundance trends of [Cu/...

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 large areas of the ocean phytoplankton growth is limited by the scarcity of iron (Fe), an essential co-factor for multiple enzymes. Phytoplankton has hence developed strategies to survive under Fe limitation. Here, we characterize the response to Fe limitation of the cyanobacterium Synechococcus sp. PCC7002 acclimated to different Fe concentrations in chemically characterized synthetic seawa...

Iron (Fe) minerals and ferrous iron (Fe(II)) play an important role in the several natural elemental cycles, including the carbon cycle, nutrient cycles, and the cycling of metals. In this work we have characterized the reactivity structural Fe(II) in several Fe minerals and in natural soil with uranium. We have studied the reactivity of Fe(II) in solution with the Fe oxide goethite conditions ...