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The impact of tropospheric planetary wave variability on stratospheric ozone

Description: The goal of this project was to improve understanding of the role of the stratosphere in inducing long-term variations of the chemical composition of the troposphere. Changes in stratospheric transport occur on decadel timescales in response to changes in the structure of planetary wave patterns, forced in the troposphere. For many important tracers, such as column amounts of ozone, this variability of the transport leads to changes with signatures very similar to those induced by anthropogenic releases of chemicals into the atmosphere. During this project, a new interactive two-dimensional model of the dynamics, chemistry and radiation of the stratosphere was developed. The model was used to interpret available data of tracers. It was found that a fairly coherent picture of tracer distributions is obtained when a layer of reduced gravity wave drag is assumed for the lower stratosphere. The results suggest that the power of models to predict variability in tracer transport in the upper troposphere and lower stratosphere is limited until current theories of gravity wave breaking have been refined.
Date: June 25, 2002
Creator: McElroy, Michael B. & Schneider, Hans R.
Partner: UNT Libraries Government Documents Department

String theory and non-commutative geometry [Final report]

Description: During the period of the three-year DOE grant DEFG02-94ER-25228, granted for the period August 1, 1997 to July 31, 2000, and extended until July 31, 2001, the investigator made significant progress and achieved most of the proposed goals. He completed certain older work, discovered a number of fundamental new theoretical phenomena, developed theories about them, and we began a project to integrate twist quantum fields into constructive quantum field theory, and to determine the effects of twisting on breaking supersymmetry.
Date: November 19, 2001
Creator: Jaffe, Arthur
Partner: UNT Libraries Government Documents Department

Final progress report for DOE grant [Protein dynamics and biocatalysis]

Description: The purpose of this project was to develop and apply large-scale computer simulation methods to enzyme reactions and protein dynamics. New approaches based on the QM/MM methodology were formulated. New insights on the reaction mechanisms of triosephosphate isomerase and chorismate mutase were obtained.
Date: September 3, 2001
Creator: Karplus, Martin
Partner: UNT Libraries Government Documents Department

Remote facility sharing with ATM networks [PC based ATM Link Delay Simulator (LDS)]. Final report

Description: The ATM Link Delay Simulator (LDS) adds propagation delay to the ATM link on which it is installed, to allow control of link propagation delay in network protocol experiments simulating an adjustable piece of optical fiber. Our LDS simulates a delay of between 1.5 and 500 milliseconds and is built with commodity PC hardware, only the ATM network interface card is not generally available. Our implementation is special in that it preserves the exact spacing of ATM data cells a feature that requires sustained high performance. Our implementation shows that applications demanding sustained high performance are possible on commodity PC hardware. This illustrates the promise that PC hardware has for adaptability to demanding specialized testing of high speed network.
Date: June 1, 2001
Creator: Kung, H. T.
Partner: UNT Libraries Government Documents Department

Mathematics and string theory

Description: The continuation of the collaboration with Liu and Lian on the calculation of the II A model opened up the possibility to understand calculations for higher genus curves also; many detailed calculations were carried out. They provided evidence that the method is powerful enough to calculate GW invariants in many cases. Local mirror symmetry was worked out with Chiang, Klemm, and Zaslow; it is consistent with physics intuition. Work was carried out to advance the ideas of Stroninger-Yau-Zaslow's geometric version of mirror symmetry in terms of special Lagragian torus fibration. Several papers were written on understanding such duality; it fits well with the predictions, and the ideas are still being studied.
Date: November 25, 2002
Creator: Yau, Shing-Tung
Partner: UNT Libraries Government Documents Department

Final report. Technology innovation for global change: The role of assessment, R and D, and regulation

Description: Through the research carried out under this grant, we have made considerable progress in addressing our fundamental research question: How and under what conditions can government stimulate radical technological innovation? More specifically, we have analyzed three pathways through which government may influence the decisions by firms to invest in radical technological innovation: technological opportunism (supply-push policies), regulatory responsiveness (demand-pull policies) and anticipatory action (assessments and information policy). We have produced several written documents, as well as made several presentations of our work. We are now working on a book based on this research, which we will have to a publisher in 2002. We are also pursuing other opportunities for dissemination of the results, including both presentations and articles in the academic and policy press.
Date: November 29, 2001
Creator: Clark, William C.; Holdren, John P. & Norberg-Bohm, Vicki
Partner: UNT Libraries Government Documents Department

Effect of Tensor Range in Nuclear Two-Body Problems

Description: The interaction between neutron and proton in the triplet state has been investigated. The central and tensor potentials have been assumed to be of the ''meson'' type but of possibly different ranges. The variational-iterational method has been utilized to determine V{sub o}, the strength of the central potential, and {gamma}V{sub o}, the strength of the tensor potential. A wide variation in the values of both central and tensor ranges were included. Calculations of this type have proved difficult in the past principally because of the sensitivity of the results to the quadrupole moment Q of the deuteron for which accurate wave functions are necessary. It would be desirable to have a more accurate value of Q deduced from experiment. The percent D state in the deuteron and the effective triplet range have also been computed. The results are applied to the discussion of the magnetic moment of the deuteron, the photoelectric disintegration of the deuteron, and neutron-proton scattering. It is concluded that experimental information on neutron-proton interaction at their present accuracy does not determine the range of the tensor forces except within rather broad limits. A decrease in the uncertainty in the triplet range by an order of magnitude would be required. Finally it is concluded that charge independence of nuclear forces can be maintained with the meson well.
Date: November 1, 1949
Creator: Feshbach, H.; Schwinger, J. & Harr, J.A.
Partner: UNT Libraries Government Documents Department

Land-use change and carbon sinks: Econometric estimation of the carbon sequestration supply function

Description: Increased attention by policy makers to the threat of global climate change has brought with it considerable interest in the possibility of encouraging the expansion of forest area as a means of sequestering carbon dioxide. The marginal costs of carbon sequestration or, equivalently, the carbon sequestration supply function will determine the ultimate effects and desirability of policies aimed at enhancing carbon uptake. In particular, marginal sequestration costs are the critical statistic for identifying a cost-effective policy mix to mitigate net carbon dioxide emissions. We develop a framework for conducting an econometric analysis of land use for the forty-eight contiguous United States and employing it to estimate the carbon sequestration supply function. By estimating the opportunity costs of land on the basis of econometric evidence of landowners' actual behavior, we aim to circumvent many of the shortcomings of previous sequestration cost assessments. By conducting the first nationwide econometric estimation of sequestration costs, endogenizing prices for land-based commodities, and estimating land-use transition probabilities in a framework that explicitly considers the range of land-use alternatives, we hope to provide better estimates eventually of the true costs of large-scale carbon sequestration efforts. In this way, we seek to add to understanding of the costs and potential of this strategy for addressing the threat of global climate change.
Date: January 1, 2001
Creator: Lubowski, Ruben N.; Plantinga, Andrew J. & Stavins, Robert N.
Partner: UNT Libraries Government Documents Department

Biofuels and certification. A workshop at the Harvard Kennedy School of Government. Summary report

Description: Liquid biofuels can provide a substitute for fossil fuels in the transportation sector. Many countries have mandated the use of biofuels, by creating targets for their use. If not implemented with care, however, actions that increase biofuel production can put upward pressure on food prices, increase greenhouse gas (GHG) emissions, and exacerbate degradation of land, forest, and water sources. A strong global biofuels industry will not emerge unless these environmental and social concerns are addressed. Interested parties around the world are actively debating the design and implementation of policies to meet the biofuel goals, particularly those established in the United States and Europe. In general, policy options for managing the potential risks and benefits of biofuel development should specify not only clear standards governing biofuel content and production processes, but also certification processes for verifying whether particular biofuels meet those standards, and specific metrics or indicators on which to base the certification. Historically, many standards in the energy and environment fields have ultimately been set or supported by governments. Many of the certification processes have been voluntary, carried out by independent third parties. The biofuels case is a young one, however, with questions of goals, standards, certification, and metrics still in interdependent flux. The workshop focused its discussions on certification issues, but found the discussions naturally reaching into ongoing debates regarding possible goals, standards, and metrics. Many countries are proposing that for a biofuel to qualify as contributing to government-mandated targets or goals, it must be certified to meet certain standards. These standards could be limited to the amount of GHG emitted in the production process or could include a number of other environmental sustainability concerns ranging from deforestation and biodiversity to water resources. While the threat to both forests and food supplies from increased biofuel production is real, it ...
Date: June 1, 2009
Creator: Devereaux, Charan & Lee, Henry
Partner: UNT Libraries Government Documents Department

A Joint Workshop on Promoting the Development and Deployment of IGCC/Co-Production/CCS Technologies in China and the United States. Workshop report

Description: With both China and the United States relying heavily on coal for electricity, senior government officials from both countries have urged immediate action to push forward technology that would reduce carbon dioxide emissions from coal-fired plants. They discussed possible actions at a high-level workshop in April 2009 at the Harvard Kennedy School jointly sponsored by the Belfer Center's Energy Technology Innovation Policy (ETIP) research group, China's Ministry of Science and Technology, and the Chinese Academy of Sciences. The workshop examined issues surrounding Integrated Gasification Combined Cycle (IGCC) coal plants, which turn coal into gas and remove impurities before the coal is combusted, and the related carbon capture and sequestration, in which the carbon dioxide emissions are captured and stored underground to avoid releasing carbon dioxide into the atmosphere. Though promising, advanced coal technologies face steep financial and legal hurdles, and almost certainly will need sustained support from governments to develop the technology and move it to a point where its costs are low enough for widespread use.
Date: June 3, 2009
Creator: Zhao, Lifeng; Ziao, Yunhan & Gallagher, Kelly Sims
Partner: UNT Libraries Government Documents Department

Realistic costs of carbon capture

Description: There is a growing interest in carbon capture and storage (CCS) as a means of reducing carbon dioxide (CO2) emissions. However there are substantial uncertainties about the costs of CCS. Costs for pre-combustion capture with compression (i.e. excluding costs of transport and storage and any revenue from EOR associated with storage) are examined in this discussion paper for First-of-a-Kind (FOAK) plant and for more mature technologies, or Nth-of-a-Kind plant (NOAK). For FOAK plant using solid fuels the levelised cost of electricity on a 2008 basis is approximately 10 cents/kWh higher with capture than for conventional plants (with a range of 8-12 cents/kWh). Costs of abatement are found typically to be approximately US$150/tCO2 avoided (with a range of US$120-180/tCO2 avoided). For NOAK plants the additional cost of electricity with capture is approximately 2-5 cents/kWh, with costs of the range of US$35-70/tCO2 avoided. Costs of abatement with carbon capture for other fuels and technologies are also estimated for NOAK plants. The costs of abatement are calculated with reference to conventional SCPC plant for both emissions and costs of electricity. Estimates for both FOAK and NOAK are mainly based on cost data from 2008, which was at the end of a period of sustained escalation in the costs of power generation plant and other large capital projects. There are now indications of costs falling from these levels. This may reduce the costs of abatement and costs presented here may be 'peak of the market' estimates. If general cost levels return, for example, to those prevailing in 2005 to 2006 (by which time significant cost escalation had already occurred from previous levels), then costs of capture and compression for FOAK plants are expected to be US$110/tCO2 avoided (with a range of US$90-135/tCO2 avoided). For NOAK plants costs are expected to be US$25-50/tCO2. Based on ...
Date: July 1, 2009
Creator: Al Juaied, Mohammed (Harvard Univ., Cambridge, MA (US). Belfer Center for Science and International Affiaris) & Whitmore, Adam (Hydrogen Energy International Ltd., Weybridge (GB))
Partner: UNT Libraries Government Documents Department

Technology and international climate policy

Description: Both the nature of international climate policy architectures and the development and diffusion of new energy technologies could dramatically influence future costs of reducing global emissions of greenhouse gases. This paper explores the implications of interactions between technology availability and performance and international policy architectures for technology choice and the social cost of limiting atmospheric CO2 concentrations to 500 ppm by the year 2095. Key issues explored in the paper include the role of bioenergy production with CO2 capture and storage (CCS), overshoot concentration pathways, and the sensitivity of mitigation costs to policy and technology.
Date: May 1, 2009
Creator: Clarke, Leon; Calvin, Kate; Edmonds, James A.; Kyle, Page & Wise, Marshall
Partner: UNT Libraries Government Documents Department

DOE FY 2010 Budget Request and Recovery Act Funding for Energy Research, Development, Demonstration, and Deployment: Analysis and Recommendations

Description: The combination of the FY 2010 budget request for the Department of Energy (DOE) and the portion of the American Recovery and Reinvestment Act of 2009 (ARRA) funds likely to be available in 2010 would (assuming that they would be split evenly between FY 2010 and FY 2011) result in a doubling in funding available for energy research, development, and deployment (ERD and D) from $3.6 billion in FY 2009 to $7.2 billion in FY 2010. Without the stimulus funds, DOE ERD and D investments in FY 2010 would decrease very slightly when compared to FY 2009. Excluding the $7.5 billion for the Advanced Technology Vehicles Manufacturing Loans in FY 2009, the FY 2010 budget request for deployment represents a 33 percent decrease from the FY 2009 levels from $520 million to $350 million. This decrease is largely due to the large amounts of funds appropriated in ARRA for DOE deployment programs, or $23.6 billion, which are three times greater than those appropriated in the FY 2009 budget. These very substantial funding amounts, coupled with the broad range of institutional innovations the administration is putting in place and movement toward putting a price on carbon emissions, will help accelerate innovation for a broad range of energy technologies. DOE's Advanced Research Projects Agency-Energy (ARPA-E) and the Energy Innovation Hubs are important initiatives that could contribute to two weak points of the government's energy innovation effort, namely funding high-risk projects in transformational technologies and in companies that have not traditionally worked with the government and strengthening the integration of basic and applied research in priority areas. Increasing the funding for different types of energy storage research, providing some support for exploring opportunities in coal-to-liquids with carbon capture and storage (CCS) and coal-and-biomass-to-liquids with CCS, and reducing funding for fission RD and D ...
Date: June 1, 2009
Creator: Anadon, Laura Diaz; Gallagher, Kelly Sims & Bunn, Matthew
Partner: UNT Libraries Government Documents Department

In-use vehicle emissions in China: Beijing study

Description: China's economic boom in the last three decades has spurred increasing demand for transportation services and personal mobility. Consequently, vehicle population has grown rapidly since the early 1990s, especially in megacities such as Beijing, Guangzhou, and Tianjin. As a result, mobile sources have become more conspicuous contributors to urban air pollution in Chinese cities. Tianjin was our first focus city, and the study there took us about two years to complete. Building upon the experience and partnership generated through the Tianjin study, the research team carried out the Beijing study from fall 2007–fall 2008. Beijing was chosen to be our second focus city for several reasons: it has the largest local fleet and the highest percentage of the population owning vehicles among all Chinese cities, and it has suffered from severe air pollution, partially due to the ever-growing population of on-road vehicles.
Date: May 1, 2009
Creator: Oliver, Hongyan H.; Gallagher, Kelly Sims; Li, Mengliang; Qin, Kongjian; Zhang, Jianwei; Liu, Huan et al.
Partner: UNT Libraries Government Documents Department

Proposed roadmap for overcoming legal and financial obstacles to carbon capture and sequestration

Description: Many existing proposals either lack sufficient concreteness to make carbon capture and geological sequestration (CCGS) operational or fail to focus on a comprehensive, long term framework for its regulation, thus failing to account adequately for the urgency of the issue, the need to develop immediate experience with large scale demonstration projects, or the financial and other incentives required to launch early demonstration projects. We aim to help fill this void by proposing a roadmap to commercial deployment of CCGS in the United States.This roadmap focuses on the legal and financial incentives necessary for rapid demonstration of geological sequestration in the absence of national restrictions on CO2 emissions. It weaves together existing federal programs and financing opportunities into a set of recommendations for achieving commercial viability of geological sequestration.
Date: March 1, 2009
Creator: Jacobs, Wendy; Chohen, Leah; Kostakidis-Lianos, Leah & Rundell, Sara
Partner: UNT Libraries Government Documents Department

Tackling U.S. energy challenges and opportunities: preliminary policy recommendations for enhancing energy innovation in the United States

Description: The report offers preliminary recommendations for near-term actions to strengthen the U.S. effort to develop and deploy advanced energy technologies. The report comes as the Obama Administration and the 111th U.S. Congress face enormous challenges and opportunities in tackling the pressing security, economic, and environmental problems posed by the energy sector. Improving the technologies of energy supply and end-use is a prerequisite for surmounting these challenges in a timely and cost-effective way, and this report elaborates on how policy can support develop of these important energy technologies.
Date: February 18, 2009
Creator: Anadon, Laura Diaz; Gallagher, Kelly Sims; Bunn, Matthew & Jones, Charles
Partner: UNT Libraries Government Documents Department