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Without iron and stony-iron meteorites, our chances of ever sampling the deep interior of a differentiated planetary object would be next to nil. Although we live on a planet with a very substantial core, we will never be able to sample it. Fortunately, asteroid collisions provide us with a rich sampling of the deep interiors of differentiated asteroids. Iron and stony-iron meteorites are fragments of a large number of asteroids that underwent significant geological processing in the early solar system. Parent bodies of iron and some stony-iron meteorites completed a geological evolution similar to that continuing on Earth – although on much smaller length- and timescales – with melting of the metal and silicates; differentiation into core, mantle, and crust; and probably extensive volcanism. Iron and stony-iron meteorites are our only available analogues to materials found in the deep interiors of Earth and other terrestrial planets. This chapter deals with our current knowledge of these meteorites. How did they form? What can they tell us about the early evolution of the solar system and its solid bodies? How closely do they resemble the materials from planetary interiors? What do and do not we know?

As a prospective commercial solvent extraction (SX) process, laboratory-scale continuous tests were recently undertaken to assess the use of a solution of LIX 63 hydroxyoxime (“hydroxyoxime”) and Versatic 10 to kinetically separate cobalt from a nickel-rich sulfate solution while simultaneously rejecting manganese and magnesium. A material quantity of blue precipitate observed in the strip stage cells during decommissioning has been identified as the sulfate salt of the nickel-trishydroxyoxime complex. As precipitation during SX is undesirable, the effect of various operating parameters on precipitate formation has been investigated. Minimizing aqueous nickel and/or sulfuric acid concentration and/or increasing organic polarity can overcome this problem. Where it forms, hydroxyoxime and nickel can be recovered from the precipitate by redissolution under suitable (e.g., low acid) operating conditions. The nitrate salt counterpart of this sulfate precipitate has beencrystallographically characterized using a short chained (C8) analogue of LIX 63 hydroxyoxime, revealing the coordination of three neutral hydroxyoxime ligands around nickel, forming a monomeric coordination complex cation counterbalanced by nitrate anions.

Without iron and stony-iron meteorites, our chances of ever sampling the deep interior of a differentiated planetary object would be next to nil. Although we live on a planet with a very substantial core, we will never be able to sample it. Fortunately, asteroid collisions provide us with a rich sampling of the deep interiors of differentiated asteroids.Iron and stony-iron meteorites are fragments of a large number of asteroids that underwent significant geological processing in the early solar system. Parent bodies of iron and some stony-iron meteorites completed a geological evolution similar to that continuing on Earth – although on much smaller length- and timescales – with melting of the metal and silicates; differentiation into core, mantle, and crust; and probably extensive volcanism. Iron and stony-iron meteorites are our only available analogues to materials found in the deep interiors of Earth and other terrestrial planets. This chapter deals with our current knowledge of these meteorites. How did they form? What can they tell us about the early evolution of the solar system and its solid bodies? How closely do they resemble the materials from planetary interiors? What do and do not we know?

Martian meteorites provide our only samples for laboratory investigations of Mars, yet the lack of geologic context severely limits their utility. Strong petrologic similarities between the pyroxenitic layer of a 120-m thick, mafic Archean lava flow in Ontario, Canada, called Theo‟s Flow, to the nakhlite meteorite group may elucidate geologic processes that operated on Mars. Theo's Flow is in the Abitibi greenstone belt, an area well-known as a komatiite location. The type locality, and best outcrop, of Theo's Flow is an upturned (~70°) section stretching eastwest for ~500 m. Theo's Flow can be divided into distinct lithologic units: a thin basal peridotite (0-9 m), a thick pyroxenite (50-60 m), a gabbro (35-40 m), and a hyaloclastic, brecciated top (8-10 m). It is the thick pyroxenitic layer that bears a striking textural similarity to the martian nakhlites. Serpentinization of olivine, chloritization of orthopyroxene, and alteration (e.g., pseudomorphic replacement) of plagioclase and minor phases have transformed the original mineral assemblage, though augites remain largely unaltered and textural relationships are wellpreserved throughout the flow. Variations in iron and minor element abundances in augite cores exhibit typical trends for an evolving melt. Bulk rock analyses exhibit elemental trends consistent with an evolving melt, though they exhibit evidence of elemental re-mobilization by later metamorphism. An average of the peridotite, pyroxenite, and gabbro compositions compare well to that of the quenched top hyaloclastite, suggesting it is a single flow that differentiated by crystal settling. The lithologic diversity within Theo‟s Flow suggests nakhlites may also have complementary lithologies which remain unsampled.

OBJECTIVE: Childhood obesity is higher among ethnic minorities. One reason may be the limited access to affordable, healthy options. The disparate prevalence of urban corner stores in low-income and high-minority communities has been well documented. There are no data, however, on what children purchase in these environments before and after school. The purpose of this study was to document the nature of children's purchases in corner stores proximal to their schools. METHODS: This was an observational study from January to June 2008. Participants were children in grades 4 through 6 from 10 urban K-8 schools with ≥50% of students eligible for free or reduced-price meals. A total of 833 intercept surveys of children's purchases were conducted outside 24 corner stores before and after school. The main outcomes were type and energy content of items purchased. RESULTS: The most frequently purchased items were energy-dense, low-nutritive foods and beverages, such as chips, candy, and sugar-sweetened beverages. Students spent $1.07 ± 0.93 on 2.1 ± 1.3 items (1.6 ± 1.1 food items and 0.5 ± 0.6 beverage items) per purchase. The total number of calories purchased per trip was 1497.7 ± 1219.3 kJ (356.6 ± 290.3 kcal). More calories came from foods than from beverages. CONCLUSIONS: Purchases made in corner stores contribute significantly to energy intake among urban school children. Obesity prevention efforts, as well as broader efforts to enhance dietary quality among children in urban settings, should include corner store environments proximal to schools.

The L chondrite Patuxent Range (PAT) 91501 is an 8.5-kg unshocked, homogeneous, igneous-textured impact melt that cooled slowly compared to other meteoritic impact melts in a crater floor melt sheet or sub-crater dike [Mittlefehldt D. W. and Lindstrom M. M. (2001) Petrology and geochemistry of Patuxent Range 91501 and Lewis Cliff 88663. Meteoritics Planet. Sci. 36, 439–457]. We conducted mineralogical and tomographic studies of previously unstudied mm- to cm-sized metal–sulfide–vesicle assemblages and chronologic studies of the silicate host. Metal–sulfide clasts constitute about 1 vol.%, comprise zoned taenite, troilite, and pentlandite, and exhibit a consistent orientation between metal and sulfide and of metal–sulfide contacts. Vesicles make up 2 vol.% and exhibit a similar orientation of long axes. 39Ar–40Ar measurements probably date the time of impact at 4.461 ± 0.008 Gyr B.P. Cosmogenic noble gases and 10Be and 26Al activities suggest a pre-atmospheric radius of 40–60 cm and a cosmic ray exposure age of 25–29 Myr, similar to ages of a cluster of L chondrites. PAT 91501 dates the oldest known impact on the L chondrite parent body. The dominant vesicle-forming gas was S2 (15–20 ppm), which formed in equilibrium with impact-melted sulfides. The meteorite formed in an impact melt dike beneath a crater, as did other impact melted L chondrites, such as Chico. Cooling and solidification occurred over 2 h. During this time, 90% of metal and sulfide segregated from the local melt. Remaining metal and sulfide grains oriented themselves in the local gravitational field, a feature nearly unique among meteorites. Many of these metal–sulfide grains adhered to vesicles to form aggregates that may have been close to neutrally buoyant. These aggregates would have been carried upward with the residual melt, inhibiting further buoyancy-driven segregation. Although similar processes operated individually in other chondritic impact melts, their interaction produced the unique ass