Article on the equivalence of dipole correction and Coulomb cutoff techniques in supercell calculations. In this work, the authors compare the dipole correction and Coulomb cutoff methods under the same conditions in the framework of plane-wave based density-functional theory.

A letter report issued by the Government Accountability Office with an abstract that begins "In 2006, the U.S. Postal Service (USPS) discarded about 317,000 tons of undeliverable-as-addressed advertising mail. Such mail can be disposed of using incineration, landfills or through other methods. USPS recently committed to minimizing the agency's impact on every aspect of the environment. Recycling undeliverable advertising mail can help USPS achieve this commitment, while generating revenue and reducing its costs and financial pressures. In response to the 2006 Postal Accountability and Enhancement Act, this report addresses (1) recent mail-related recycling accomplishments (initiatives) undertaken by USPS, the mailing industry, and others and (2) additional recycling opportunities that USPS could choose to engage in, or influence mailers to undertake. To conduct this study, GAO analyzed relevant data and documents, visited USPS and other facilities, and interviewed about 40 stakeholders."

Testimony issued by the Government Accountability Office with an abstract that begins "Since 1990, GAO has designated the Department of Defense's (DOD) management of major weapon system acquisitions a high risk area. DOD has taken some action to improve acquisition outcomes, but its weapon programs continue to take longer, cost more, and deliver fewer capabilities than originally planned. These persistent problems--coupled with current operational demands--have impelled DOD to work outside of its traditional acquisition process to acquire equipment that meet urgent warfighter needs. Poor outcomes in DOD's weapon system programs reverberate across the entire federal government. Over the next 5 years, DOD plans to invest about $900 billion to develop and procure weapon systems--the highest level of investment in two decades. Every dollar wasted on acquiring weapon systems is less money available for other priorities. This testimony describes DOD's current weapon system investment portfolio, the problems that contribute to cost and schedule increases, and the potential impacts of recent legislative initiatives and DOD actions aimed at improving outcomes. It also provides some observations about what is needed for DOD to achieve lasting reform. The testimony is drawn from GAO's body of work on DOD's acquisition, requirements, and funding processes, as …

An all-inorganic photocatalytic unit consisting of a binuclear TiOCr charge-transfer chromophore coupled to an Ir oxide nanocluster has been assembled on the pore surface of mesoporous silica AlMCM-41. In situ FT-Raman and EPR spectroscopy of an aqueous suspension of the resulting IrxOy-TiCr-AlMCM-41 powder reveal the formation of superoxide species when exciting the Ti(IV)OCr(III) --> Ti(III)OCr(IV) metal-to-metal charge-transfer chromophore with visible light. Use of H218O confirms that the superoxide species originates from oxidation of water. Photolysis in the absence of persulfate acceptor leads to accumulation of Ti(III) instead. The results are explained by photocatalytic oxidation of water at Ir oxide nanoclusters followed by trapping of the evolving O2 by transient Ti(III) centers to yield superoxide. Given the flexibility to select donor metals with appropriate redox potential, photocatalytic units consisting of a binuclear charge-transfer chromophore coupled to a water oxidation catalyst shown here constitute a step towards thermodynamically efficient visible light water oxidation units.

ENERGY STAR is a voluntary energy efficiency-labeling program operated jointly by the United States Department of Energy and the United States Environmental Protection Agency (US EPA). Since the program inception in 1992, ENERGY STAR has become a leading international brand for energy efficient products. ENERGY STAR's central role in the development of regional, national, and international energy programs necessitates an open process whereby its program achievements to date as well as projected future savings are shared with committed stakeholders. Through 2006, US EPA?S ENERGY STAR labeled products saved 4.8 EJ of primary energy and avoided 82 Tg C equivalent. We project that US EPA?S ENERGY STAR labeled products will save 12.8 EJ and avoid 203 Tg C equivalent over the period 2007-2015. A sensitivity analysis examining two key inputs (carbon factor and ENERGY STAR unit sales) bounds the best estimate of carbon avoided between 54 Tg C and 107 Tg C (1993 to 2006) and between 132 Tg C and 278 Tg C (2007 to 2015).

The compound (bpy)2MnIII(mu-O)2MnIV(bpy)2, a structural model relevant for the photosynthetic water oxidation complex, was coupled to single CrVI charge-transfer chromophores in the channels of the nanoporous oxide AlMCM-41. Mn K-edge EXAFS spectroscopy confirmed that the di-mu-oxo dinuclear Mn core of the complex is unaffected when loaded into the nanoscale pores. Observation of the 16-line EPR signal characteristic of MnIII(mu-O)2MnIV demonstrates that the majority of the loaded complexes retained their nascent oxidation state in the presence or absence of CrVI centers. The FT-Raman spectrum upon visible light excitation of the CrVI-OII --> CrV-OI ligand-to-metal charge-transfer reveals electron transfer from MnIII(mu-O)2MnIV (Mn-O stretch at 700 cm-1) to CrVI, resulting in the formation of CrV and MnIV(mu-O)2MnIV (Mn-O stretch at 645 cm-1). All initial and final states are directly observed by FT-Raman or EPR spectroscopy, and the assignments corroborated by X-ray absorption spectroscopy measurements. The endoergic charge separation products (DELTA Eo = -0.6 V) remain after several minutes, which points to spatial separation of CrV and MnIV(mu-O)2MnIV as a consequence of hole (OI) hopping as a major contributing mechanism. This is the first observation of visible light-induced oxidation of a potential water oxidation complex by a metal charge-transfer pump in a nanoporous environment. …

Free weekly newspaper that includes business and classified advertising.

Free weekly newspaper that includes business and classified advertising.

This report introduces the reader to fundamentals of the climate change issue. Part one summarizes current understandings and controversies concerning the science, economics, international cooperation, and other aspects of the climate change policy problem. Part two is a brief update on the status of domestic and international policies. Part three outlines the policy toolbox seen as being available to policymakers to address the challenge as they define the emerging legislative agenda.

This report summarizes some of the domestic agriculture and forestry provisions in the Lieberman-Warner Climate Security Act of 2008 (S. 3036, formerly S. 2191), as ordered reported out of the Senate Committee on Environment and Public Works in December 2007.

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This report provides an overview of U.S.-Mexico economic relations, trade trends, the Mexican economy, NAFTA, and trade issues between the United States and Mexico.

This report provides an overview of recent U.N. efforts to address VAW and highlights key U.N. interagency efforts. It also discusses selected U.N. funds, programs, and agencies that address international violence against women. It does not assess the extent to which VAW is directly addressed or is part of a larger initiative or program.

This report addresses causes, prevalence, and consequences of violence against women. It provides examples of U.S. activities that address violence against women (VAW) directly or include anti-VAW components. It also outlines possible policy considerations for the 110th Congress, including the scope and effectiveness of U.S. programs; further integrating anti-VAW programs into U.S. assistance and foreign policy mechanisms; and strengthening U.S. government coordination of anti-VAW activities.

This report outlines the organizational structure of United States Northern Command (NORTHCOM), explains how NORTHCOM contributes to homeland security through the interagency process, and summarizes NORTHCOM's international relationships with Canada and Mexico. Some issues for Congress involving NORTHCOM include Department of Defense (DOD) reorganization and the Unified Command Plan, improving interagency relationships, NORTHCOM's increased reliance on reserve component service members, the ongoing Cheyenne Mountain Operations Center realignment, and the allocation of resources necessary for NORTHCOM to successfully plan for and execute its assigned missions.

This report discusses the petroleum refining industry and its relation to the economy. Along with volatile changes in crude oil prices, the industry has faced evolving health, safety, and environmental requirements which have changed and multiplied product specifications and required capital investment in refineries. This report also seeks to describe the recent performance of the refining industry, to evaluate the structural changes that are occurring in the industry, and to analyze the nature and effects of the challenges confronting the industry.

This report introduces the reader to fundamentals of the climate change issue. Part one summarizes current understandings and controversies concerning the science, economics, international cooperation, and other aspects of the climate change policy problem. Part two is a brief update on the status of domestic and international policies. Part three outlines the policy toolbox seen as being available to policymakers to address the challenge as they define the emerging legislative agenda.

This report provides a brief overview of the climate change issue as well as other Clean Air Act issues of interest in the 110th Congress.

This report will identify and discuss oversight issues and legislation introduced in the 110th Congress to address specific concerns related to how ESA is implemented and how endangered species are managed, and will be updated periodically to reflect legislative action.

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This report provides an overview of the current structure of the federal communications commission and its role in the changing telecommunications landscape.

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Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.