Selecting and Planting Shade Trees

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Ornamental Evergreens

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Structure and dynamics in nanoionic materials

Nanomaterials, materials with particle dimensions less than 100 nm, show a range of unusual properties when compared with their bulk counterparts. Atomic transport is one of these properties and nanomaterials have been reported as having exceptionally high diffusion coefficients. In the case of ionic materials the atomic transport is important in a number of technological applications where they are used as solid electrolytes, for example in sensors, batteries and fuel cells. Hence ionic nanomaterials often referred to as nanoionics, can offer the means of producing electrolytes with improved performance. This contribution will examine the mechanisms of atomic transport in nanoionics in two model materials, zirconia and lithium niobate. Since an understanding of these mechanisms is dependent on knowledge of the microstructure of the materials consideration will also be given to the structural characterisation of the materials, with a focus on X-ray absorption spectroscopy. The use of this technique to characterise mesoporous a-Fe2O3 is also discussed

Timescales of carbon turnover in soils with mixed crystalline mineralogies

Organic matter–mineral associations stabilize much of the carbon (C) stored globally in soils. Metastable short-range-order (SRO) minerals such as allophane and ferrihydrite provide one mechanism for long-term stabilization of organic matter in young soil. However, in soils with few SRO minerals and a predominance of crystalline aluminosilicate or Fe (and Al) oxyhydroxide, C turnover should be governed by chemisorption with those minerals. Here, we correlate mineral composition from soils containing small amounts of SRO minerals with mean turnover time (TT) of C estimated from radiocarbon (¹⁴C) in bulk soil, free light fraction and mineral-associated organic matter. We varied the mineral amount and composition by sampling ancient soils formed on different lithologies in arid to subhumid climates in Kruger National Park (KNP), South Africa. Mineral contents in bulk soils were assessed using chemical extractions to quantify Fe oxyhydroxides and SRO minerals. Because of our interest in the role of silicate clay mineralogy, particularly smectite (2 : 1) and kaolinite (1 : 1), we separately quantified the mineralogy of the clay-sized fraction using X-ray diffraction (XRD) and measured ¹⁴C on the same fraction. <br><br> Density separation demonstrated that mineral associated C accounted for 40–70 % of bulk soil organic C in A and B1 horizons for granite, nephelinite and arid-zone gabbro soils, and &gt; 80 % in other soils. Organic matter strongly associated with the isolated clay-sized fraction represented only 9–47 % of the bulk soil C. The mean TT of C strongly associated with the clay-sized fraction increased with the amount of smectite (2 : 1 clays); in samples with &gt; 40 % smectite it averaged 1020 ± 460 years. The C not strongly associated with clay-sized minerals, including a combination of low-density C, the C associated with minerals of sizes between 2 µm and 2 cm (including Fe oxyhydroxides as coatings), and C removed from clay-sized material by 2 % hydrogen peroxide had TTs averaging 190 ± 190 years in surface horizons. Summed over the bulk soil profile, we found that smectite content correlated with the mean TT of bulk soil C across varied lithologies. The SRO mineral content in KNP soils was generally very low, except for the soils developed on gabbros under more humid climate that also had very high Fe and C contents with a surprisingly short, mean C TTs. In younger landscapes, SRO minerals are metastable and sequester C for long timescales. We hypothesize that in the KNP, SRO minerals represent a transient stage of mineral evolution and therefore lock up C for a shorter time. <br><br> Overall, we found crystalline Fe-oxyhydroxides (determined as the difference between Fe in dithionate citrate and oxalate extractions) to be the strongest predictor for soil C content, while the mean TT of soil C was best predicted from the amount of smectite, which was also related to more easily measured bulk properties such as cation exchange capacity or pH. Combined with previous research on C turnover times in 2 : 1 vs. 1 : 1 clays, our results hold promise for predicting C inventory and persistence based on intrinsic timescales of specific carbon–mineral interactions

The economic ecology of small businesses in Oxfordshire

Report by the Oxfordshire Economic Observatory (OEO) for the Federation of Small Businesses (FSB), Oxfordshire Branch

I\u27d Offer Thee This Hand of Mine

I’d offer thee this hand of mine, If I could love thee less, But hearts as warm as thine, Should never know distress. My fortune is too hard for thee ‘Twould chill thy dearest joy, I’d rather weep to see thee free, Than win thee to destroy. I leave thee in thy happiness, As one to dear too love, As one I think of but to bless, As wretchedly I rove; But oh! When sorrows cup I drink, All better tho’ it be, How sweet ‘twill be for me to think, It holds no drop for thee. And now my dreams are sadly o’er, Fate bids them to depart And I must leave my native shore, In brokenness of heart; Then oh dear one when far from thee, I ne’er know joy again, I would not, that one thought of me Should give thy bosom pain

The Surface of 2003 EL_(61) in the Near-Infrared

We report the detection of crystalline water ice on the surface of 2003 EL_(61). Reflectance spectra were collected from the Gemini North telescope in the 1.0 to 2.4 μm wavelength range and from the Keck telescope across the 1.4-2.4 μm wavelength range. The signature of crystalline water ice is obvious in all data collected. Like the surfaces of many outer solar system bodies, the surface of 2003 EL_(61) is rich in crystalline water ice, which is energetically less favored than amorphous water ice at low temperatures, suggesting that resurfacing processes may be taking place. The near-infrared color of the object is much bluer than a pure water ice model. Adding a near-infrared blue component such as hydrogen cyanide or phyllosilicate clays improves the fit considerably, with hydrogen cyanide providing the greatest improvement. The addition of hydrated tholins and bitumens also improves the fit, but is inconsistent with the neutral V - J reflectance of 2003 EL_(61). A small decrease in reflectance beyond 2.3 μm may be attributable to cyanide salts. Overall, the reflected light from 2003 EL_(61) is best fit by a model of 2/3-4/5 pure crystalline water ice and 1/3-1/5 near-infrared blue component such as hydrogen cyanide or kaolinite. The surface of 2003 EL_(61) is unlikely to be covered by significant amounts of dark material such as carbon black, as our pure ice models reproduce published albedo estimates derived from the spin state of 2003 EL_(61)

Not So Good: The Classification of “Smart Goods” Under UCC Article 2

Refrigerators can now tweet. Today, almost sixty years after the states widely adopted the Uniform Commercial Code (UCC), the line between goods and services is more blurred than ever. When the UCC was drafted, a good was the simple opposite of a service. A good was something “movable” and tangible, and a service was not. Article 2 of the UCC, which governs sales, limits its scope to goods. However, because Article 2 was drafted long before the proliferation of so-called “smart goods,” courts continuously struggle to determine when a smart good falls within Article 2’s scope. Courts have developed different tests over the years to deal with contracts containing a mixture of goods and services, but those tests produce questionable results when applied to smart goods. In the late 1990s,drafters attempted to address these issues with an ill-fated addition to Article 2 that ultimately failed. Still today, as software and tangible goods become more intertwined, software’s legal status remains a fundamental, yet unanswered, question. This unresolved question impacts consumers directly; whether a contract falls within the scope of Article 2 affects customers’ available warranties and remedies. This Note discusses the classification difficulties posed by modern goods with embedded software and services. Part I explains the history of the UCC, the past efforts to address the difficulties, and the issues that still remain. Part II analyzes previous attempts to resolve the issue and courts’ current solutions to these classification difficulties. Part III proposes a contemporary solution to these modern challenges and discusses how such a solution might be implemented

Meeting the challenge of diversity : ministry and mission in a multicultural milieu

https://place.asburyseminary.edu/ecommonsatsdissertations/1738/thumbnail.jp