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Ecological and economic systems are open systems that require energy to change the thermodynamic states of materials from naturally occurring to more valued forms. These changes are accompanied by information flows and changes in the order of systems and their surroundings. In this paper, thermodynamics is used to assess these system changes and relate them to the knowledge present in a system. Particular emphasis is given to (1) the fundamental relationships among material, energy and information flows, and changes in order and knowledge, (2) the role of equilibrium and non-equilibrium thermodynamics in assessing system change, (3) the increasing role of material and energy flows through economic systems, and (4)...
Global energy demand is expected to increase steeply, creating an urgent need to evolve a judicious global energy policy, exploiting the potential of all available energy resources, including nuclear energy. With increasing awareness of environmental issues, nuclear energy is expected to play an important role on the energy scenario in the coming decades. The immediate thrust in the science and technology of nuclear materials is to realize a robust reactor technology with associated fuel cycle and ensure the cost competitiveness of nuclear power and to extend the service life of reactors to 100 years. Accordingly, the present-generation materials need to be modified to meet the demands of prolonged exposure to irradiation...
Detection and control of harmful environments is a classical public health strategy. This strategy can be applied to the social as well as to the biological and physical environments. This article seeks to highlight some of the relationships between the health of individuals and the social environments in which they exist. It is indicated that in many instances, it may be desirable to change the public health paradigm from the bio-individual to the social level because some of the most powerful forces that affect change in disease patterns and in the health of populations can oJ~en operate at this level Although the discussions in this article are mainly rooted in the Indian social and cultural context, the conclusions...
In response to the increasing global demand for energy, on exploration and development are expanding into frontier areas of the Arctic, where slow-growing tundra vegetation and the underlying permafrost Soils are Very sensitive to disturbance. The creation of vehicle trails on the tundra from seismic exploration for on has accelerated in the past decade, and the cumulative impact represents a geographic footprint that covers a greater extent of Alaska's North Slope tundra than all other direct human impacts combined. Seismic exploration for on and gas was conducted on the coastal plain of the Arctic National Wildlife Refuge, Alaska, USA, in the winters of 1984 and 1985. This study documents recovery Of vegetation...
The success of carbon capture, storage and sequestration as a greenhouse gas mitigation strategy will be, in part, dependent on the regulatory framework used to govern its implementation. Creating a science-based regulatory framework that is designed with enough flexibility to encourage greenhouse gas offset activity, effective means of measuring the costs of taking action to reduce greenhouse gas emissions, and ample protection for human and ecosystem health may prove challenging. For the purposes of this paper we will assume that there is an existing incentive to capture, store and sequester carbon and focus on how to regulate the process. Accounting practices and precursory crediting rules for biological sinks...
As the United States moves closer to a national climate change policy, it will have to focus on a variety of factors affecting the manner in which the country moves toward a future with a substantially lower carbon footprint. In addition to encouraging renewable energy, smart grid, clean fuels and other technologies, the United States will need to make substantial infrastructure investments in a variety of industries. Among the significant contributors to the current carbon footprint in the United States is the use of coal as a major fuel for the generation of electricity. One of the most important technologies that the United States can employ to reduce its carbon footprint is to sequester the carbon dioxide ("CO2")...
As the United States moves closer to a national climate change policy, it will have to focus on a variety of factors affecting the manner in which the country moves toward a future with a substantially lower carbon footprint. In addition to encouraging renewable energy, smart grid, clean fuels and other technologies, the United States will need to make substantial infrastructure investments in a variety of industries. Among the significant contributors to the current carbon footprint in the United States is the use of coal as a major fuel for the generation of electricity. One of the most important technologies that the United States can employ to reduce its carbon footprint is to sequester the carbon dioxide ("CO2")...
Why did nuclear energy policies in France, Sweden, and the United States, very similar at the time of the oil crisis of 1973 and 1974, diverge so greatly in the following years? In answering this question, James Jasper challenges one of the most popular trends in political analysis: explanations relying exclusively on political and economic structures to account for public policies. Jasper proposes a new cultural and state-centered approach--one heeding not only structural factors but cultural meanings, individual biographies, and elite discretion. Surveying the period from the successful commercialization of light-water-reactor technology in the early 1960s to the present, he explains the events that occurred after...
Why did nuclear energy policies in France, Sweden, and the United States, very similar at the time of the oil crisis of 1973 and 1974, diverge so greatly in the following years? In answering this question, James Jasper challenges one of the most popular trends in political analysis: explanations relying exclusively on political and economic structures to account for public policies. Jasper proposes a new cultural and state-centered approach--one heeding not only structural factors but cultural meanings, individual biographies, and elite discretion. Surveying the period from the successful commercialization of light-water-reactor technology in the early 1960s to the present, he explains the events that occurred after...
The success of carbon capture, storage and sequestration as a greenhouse gas mitigation strategy will be, in part, dependent on the regulatory framework used to govern its implementation. Creating a science-based regulatory framework that is designed with enough flexibility to encourage greenhouse gas offset activity, effective means of measuring the costs of taking action to reduce greenhouse gas emissions, and ample protection for human and ecosystem health may prove challenging. For the purposes of this paper we will assume that there is an existing incentive to capture, store and sequester carbon and focus on how to regulate the process. Accounting practices and precursory crediting rules for biological sinks...
In order to identify approaches for integrated gasification combined cycle (IGCC) plant optimization it is necessary to analyse where and why the losses in the process occur. Therefore a structured exergy analysis of an IGCC with carbon capture was performed to identify losses on a plant, subsystem and individual component level. The investigation of the IGCC base case revealed an exergetic efficiency of 40%. Thus, 60% of the whole fuel exergy is lost in the process. On the subsystem level it was found that the major loss contributor is the combined cycle followed by the gas treatment section and the gasification island. Furthermore, it was demonstrated that the significance of the losses is higher in upstream processes...
Why did nuclear energy policies in France, Sweden, and the United States, very similar at the time of the oil crisis of 1973 and 1974, diverge so greatly in the following years? In answering this question, James Jasper challenges one of the most popular trends in political analysis: explanations relying exclusively on political and economic structures to account for public policies. Jasper proposes a new cultural and state-centered approach--one heeding not only structural factors but cultural meanings, individual biographies, and elite discretion. Surveying the period from the successful commercialization of light-water-reactor technology in the early 1960s to the present, he explains the events that occurred after...
The Shale Gas Subcommittee of the Secretary of Energy Advisory Board is charged with identifying measures that can be taken to reduce the environmental impact and improve the safety of shale gas production. Natural gas is a cornerstone of the U.S. economy, providing a quarter of the country’s total energy. Owing to breakthroughs in technology, production from shale formations has gone from a negligible amount just a few years ago to being almost 30 percent of total U.S. natural gas production. This has brought lower prices, domestic jobs, and the prospect of enhanced national security due to the potential of substantial production growth. But the growth has also brought questions about whether both current and future...
The success of carbon capture, storage and sequestration as a greenhouse gas mitigation strategy will be, in part, dependent on the regulatory framework used to govern its implementation. Creating a science-based regulatory framework that is designed with enough flexibility to encourage greenhouse gas offset activity, effective means of measuring the costs of taking action to reduce greenhouse gas emissions, and ample protection for human and ecosystem health may prove challenging. For the purposes of this paper we will assume that there is an existing incentive to capture, store and sequester carbon and focus on how to regulate the process. Accounting practices and precursory crediting rules for biological sinks...
Reliance on oil as an energy source for private transportation produces increasingly unfavorable social, political and environmental conditions including climate change, dependence on foreign oil, and the need for difficult choices between oil production and protection of biological systems. At the same time, the population is increasingly sedentary due largely to our reliance on the automobile for transportation. Adoption and maintenance of healthy weights and healthier lifestyles by substituting walking or biking for short trips currently taken by car could simultaneously improve health and reduce oil consumption and carbon dioxide emissions. We calculate the reduction in oil consumption and carbon dioxide emissions...
Federally owned and managed public lands occupy approximately 30 percent of the land area of the United States, and anywhere from 50 percent to more than 80 percent of the land area of many of the western states. Determining the appropriate use of these lands involves balancing objectives related to economic, recreational, and conservation interests. This paper examines established and emerging conflicts within and across these objectives through both a narrative discussion of specific topics and a series of case studies. The authors find that new challenges, including pressures to devote portions of public lands to renewable energy project development and the multifaceted threats presented by climate change, will...
Detection and control of harmful environments is a classical public health strategy. This strategy can be applied to the social as well as to the biological and physical environments. This article seeks to highlight some of the relationships between the health of individuals and the social environments in which they exist. It is indicated that in many instances, it may be desirable to change the public health paradigm from the bio-individual to the social level because some of the most powerful forces that affect change in disease patterns and in the health of populations can oJ~en operate at this level Although the discussions in this article are mainly rooted in the Indian social and cultural context, the conclusions...
Next-generation U.S. biofuel capacity should reach about 88 million gallons in 2010, thanks in large measure to one plant becoming commercially operational in 2010, using noncellulosic animal fat to produce green diesel. U.S. production capacity for cellulosic biofuels is estimated to be 10 million gallons for 2010, much less than the 100 million gallons originally mandated for use by the 2007 Energy Independence and Security Act. In early 2010, the Environmental Protection Agency lowered the cellulosic biofuel mandate to 6.5 million gallons, more in line with production prospects. Even so, expansion of next-generation fuels will have to be rapid to meet subsequent annual mandates and the longer term goal of 16...
Since the beginning of 2008, natural gas exploration activities in the Marcellus Shale Formation have increased significantly in the Commonwealth of Pennsylvania—more than 2,349 wells have been drilled, primarily in the southwest, northeast and northcentral regions. In response to the increased number of well sites and concerns about the impact of the Marcellus Shale natural gas development activities on air quality, the Pennsylvania Department of Environmental Protection (PA DEP or Department) launched a short-term, screening-level air quality sampling initiative in the northcentral region in August 2010, culminating in December 2010. This report includes the findings of the screening air sampling surveys conducted...
This research examines in detail the technology and economics of substituting biodiesel for diesel #2. This endeavor examines three areas. First, the benefits of biodiesel are examined, and the technical problems of large-scale implementation. Second, the biodiesel production possibilities are examined for soybean oil, corn oil, tallow, and yellow grease, which are the largest sources of feedstocks for the United States. Examining in detail the production possibilities allows to identity the extent of technological change, production costs, byproducts, and greenhouse gas (GHG) emissions. Finally, a U.S. agricultural model, FASOMGHG was used to predict market penetration of biodiesel, given technological progress,...