1,089 research outputs found
The Newsman\u27s Confidential Source Privilege in Virginia
The two hundredth anniversary celebration of the United States Constitution in 1987 provided an excellent opportunity to reflect upon how we now interpret the political doctrines that influenced the founding fathers in forming our government. At the time of the American Revolution, the basic tenets and freedoms that were written into the Declaration of Independence, and later incorporated into the Bill of Rights through the efforts of James Madison and George Mason of Virginia were considered essential human rights
Chronicles of Oklahoma
Article examines the relationship between cowboy philosopher Will Rogers and his rancher father, Clem Rogers, exploring the sociological and psychological friction that caused the two to have a rocky relationship over the years despite the success of both individuals
Unintended consequences of urbanization for aquatic ecosystems: A case study from the Arizona desert
Many changes wrought during the construction of "designer ecosystems" are intended to ensure - and often succeed in ensuring - that a city can provide ecosystem goods and services; but other changes have unintended impacts on the ecology of the city, impairing its ability to provide these critical functions. Indian Bend Wash, an urbanizing watershed in the Central Arizona-Phoenix (CAP) ecosystem, provides an excellent case study of how human alteration of land cover, stream channel structure, and hydrology affect ecosystem processes, both intentionally and unintentionally. The construction of canals created new flowpaths that cut across historic stream channels, and the creation of artificial lakes produced sinks for fine sediments and hotspots for nitrogen processing. Further hydrologic manipulations, such as groundwater pumping, linked surface flows to the aquifer and replaced ephemeral washes with perennial waters. These alterations of hydrologic structure are typical by-products of urban growth in arid and semiarid regions and create distinct spatial and temporal patterns of nitrogen availability. Ā© 2008 American Institute of Biological Sciences
Crystal field effects on the reactivity of aluminum-copper cluster anions
The limits and useful modifications of the jellium model are of great interest in understanding the properties of metallic clusters, especially involving bimetallic systems. We have measured the relative reactivity of CuAlān clusters (n=11ā34) with O2. An odd-even alternation is observed that is in accordance with spin-dependant etching, and CuAlā22is observed as a āmagic peak.ā The etching resistance of CuAlā22 is explained by an unusually large splitting of the 2D10 subshell that occurs because of a geometric distortion of the cluster that may also be understood as a crystal field splitting of the superatomic orbitals
Structural, electronic, and chemical properties of multiply iodized aluminum clusters
The electronic structure, stability, and reactivity of iodized aluminum clusters, which have been investigated via reactivity studies, are examined by first-principles gradient corrected density functional calculations. The observed behavior of Al13Iāx and Al14Iāx clusters is shown to indicate that for xā©½8, they consist of compact Alā13 and Al++14 cores, respectively, demonstrating that they behave as halogen- or alkaline earthlike superatoms. For x\u3e8, the Al cores assume a cagelike structure associated with the charging of the cores. The observed mass spectra of the reacted clusters reveal that Al13Iāx species are more stable for even x while Al14Iāx exhibit enhanced stability for odd x(xā©¾3). It is shown that these observations are linked to the formation and filling of āactive sites,ā demonstrating a novel chemistry of superatoms
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