Science.gov

Sample records for making energy transition

  1. Arizona's energy future: making the transition to a new mix

    SciTech Connect

    Not Available

    1981-10-01

    This report looks at Arizona's energy future in light of knowledge gained since 1976. It emphasizes conservation, cogeneration, solar, geothermal, and biomass energy promise. An interdisciplinary approach is used. (PSB)

  2. Flexible Scheduling: Making the Transition

    ERIC Educational Resources Information Center

    Creighton, Peggy Milam

    2008-01-01

    Citing literature that supports the benefits of flexible scheduling on student achievement, the author exhorts readers to campaign for flexible scheduling in their library media centers. She suggests tips drawn from the work of Graziano (2002), McGregor (2006) and Stripling (1997) for making a smooth transition from fixed to flexible scheduling:…

  3. Helping LD Students Make Transitions: Six Suggestions.

    ERIC Educational Resources Information Center

    Slade, David

    1984-01-01

    Teachers and parents can help learning disabled students make transitions to mainstream settings by preparing them for change in physical conditions, instructing them in organization and time management, teaching them interpersonal skills through role-playing, and assisting them in identifying and responding to a variety of emotions. (CL)

  4. Planning and Decision Making for Care Transitions

    PubMed Central

    Sörensen, Silvia; Mak, Wingyun; Pinquart, Martin

    2015-01-01

    The need to plan for future health care and residential adjustments increases with age, growing frailty, and restrictions in coverage of long-term care and will continue to grow with population aging. Older adults’ lack of financial preparation for health care costs, insufficient knowledge about available options, and inadequate communication about care-related values has become an increasing public health challenge. This chapter describes a model of Preparation for Future Care (PFC), which encompasses different levels and domains of planning. Research about the extent to which planning is helpful in navigating care transitions is reviewed, and barriers and facilitators of planning including individual, familial, cultural, and national long-term care policy factors are discussed. Planning in the context of dementia and practical approaches that can be taken to enhance PFC is addressed, as well as recommendations for future research in the area of planning and decision making in the context of care transitions. PMID:26207079

  5. Making energy mortgages work

    SciTech Connect

    Luboff, J.A.

    1995-05-01

    At a time when many energy efficiency projects face an uncertain future, home energy ratings and energy mortgages are receiving more attention than ever. Will enthusiasm in the industry and new programs from conventional lenders and the federal government finally open up the market? This article describes the energy morgage marketplace, how energy mortages work, and what the future holds. Topics include the following: Who`s who and what`s what in the EM marketplace; initial Freddie Mac and Fannie Mae guidelines; past and present home energy rating system; how do you score a house; how an energy mortage works; energy improvement loans; sample rating certificate; fixing the system; Colorado`s conventional market approach; US DOE`s pilot group; energy mortages set to take off.

  6. Energy development: crisis and transition

    SciTech Connect

    Gordon, L.

    1981-04-01

    The historical role of energy use in economic development has not been as clear as were the roles of land, labor, and capital until recent shortages brought it into a clearer perspective. Added to this were ambiguities in the computation of the energy consumption/economic growth relationship that overstated the fuel-conversion efficiencies of developing countries. Energy differs from other raw materials in its pervasiveness, its inability to be recycled, and its low elasticity of substitution, which make it a potential constraint on economic growth. Oil-importing developing countries accumulated large balance-of-payment deficits during the 1970s in addition to drawing down their traditional energy reserves through deforestation and the use of organic wastes as fuels. The management of a long-term energy transition is more acute for developing countries, but international cooperation to keep this transition violence-free will benefit all nations. Arguments are made for a positive response to the call for a global energy strategy. (DCK)

  7. Making energy efficiency happen

    NASA Astrophysics Data System (ADS)

    Hirst, E.

    1991-04-01

    Improving energy efficiency is the least expensive and most effective way to address simultaneously several national issues. Improving efficiency saves money for consumers, increases economic productivity and international competitiveness, enhances national security by lowering oil imports, and reduces the adverse environmental effects of energy production. This paper discusses some of the many opportunities to improve efficiency, emphasizing the roles of government and utilities.

  8. Making Sense of Energy

    ERIC Educational Resources Information Center

    Boohan, Richard

    2014-01-01

    This article describes an approach to teaching about the energy concept that aims to be accessible to students starting in early secondary school, while being scientifically rigorous and forming the foundation for later work. It discusses how exploring thermal processes is a good starting point for a more general consideration of the ways that…

  9. Process for making transition metal nitride whiskers

    DOEpatents

    Bamberger, C.E.

    1988-04-12

    A process for making metal nitrides, particularly titanium nitride whiskers, using a cyanide salt as a reducing agent for a metal compound in the presence of an alkali metal oxide. Sodium cyanide, various titanates and titanium oxide mixed with sodium oxide react to provide titanium nitride whiskers that can be used as reinforcement to ceramic composites. 1 fig., 1 tab.

  10. Process for making transition metal nitride whiskers

    DOEpatents

    Bamberger, Carlos E.

    1989-01-01

    A process for making metal nitrides, particularly titanium nitride whiskers, using a cyanide salt as a reducing agent for a metal compound in the presence of an alkali metal oxide. Sodium cyanide, various titanates and titanium oxide mixed with sodium oxide react to provide titanium nitride whiskers that can be used as reinforcement to ceramic composites.

  11. Energy Transition Initiative: Islands Playbook (Book)

    SciTech Connect

    Not Available

    2015-01-01

    The Island Energy Playbook (the Playbook) provides an action-oriented guide to successfully initiating, planning, and completing a transition to an energy system that primarily relies on local resources to eliminate a dependence on one or two imported fuels. It is intended to serve as a readily available framework that any community can adapt to organize its own energy transition effort.

  12. An Institutional Approach to Understanding Energy Transitions

    NASA Astrophysics Data System (ADS)

    Koster, Auriane Magdalena

    Energy is a central concern of sustainability because how we produce and consume energy affects society, economy, and the environment. Sustainability scientists are interested in energy transitions away from fossil fuels because they are nonrenewable, increasingly expensive, have adverse health effects, and may be the main driver of climate change. They see an opportunity for developing countries to avoid the negative consequences fossil-fuel-based energy systems, and also to increase resilience, by leap-frogging-over the centralized energy grid systems that dominate the developed world. Energy transitions pose both challenges and opportunities. Obstacles to transitions include 1) an existing, centralized, complex energy-grid system, whose function is invisible to most users, 2) coordination and collective-action problems that are path dependent, and 3) difficulty in scaling up RE technologies. Because energy transitions rely on technological and social innovations, I am interested in how institutional factors can be leveraged to surmount these obstacles. The overarching question that underlies my research is: What constellation of institutional, biophysical, and social factors are essential for an energy transition? My objective is to derive a set of "design principles," that I term institutional drivers, for energy transitions analogous to Ostrom's institutional design principles. My dissertation research will analyze energy transitions using two approaches: applying the Institutional Analysis and Development Framework and a comparative case study analysis comprised of both primary and secondary sources. This dissertation includes: 1) an analysis of the world's energy portfolio; 2) a case study analysis of five countries; 3) a description of the institutional factors likely to promote a transition to renewable-energy use; and 4) an in-depth case study of Thailand's progress in replacing nonrenewable energy sources with renewable energy sources. My research will

  13. X-Ray Transition Energies Database

    National Institute of Standards and Technology Data Gateway

    SRD 128 X-Ray Transition Energies Database (Web, free access)   This X-ray transition table provides the energies and wavelengths for the K and L transitions connecting energy levels having principal quantum numbers n = 1, 2, 3, and 4. The elements covered include Z = 10, neon to Z = 100, fermium. There are two unique features of this data base: (1) a serious attempt to have all experimental values on a scale consistent with the International System of measurement (the SI) and (2) inclusion of accurate theoretical estimates for all transitions.

  14. Energy implications of fixed rail mass transit

    SciTech Connect

    Pikarsky, M.

    1981-01-01

    Major studies on whether mass transit actually saves energy are reviewed. A possible petroleum conservation strategy that focusses on future urban and regional development is then identified. A number of U.S. cities are considered to be prime candidates for rail transit systems for the purpose of energy conservation. 30 refs.

  15. Transit station energy impacts. Research report (Interim)

    SciTech Connect

    Coleman, P.; Euritt, M.; Walton, C.M.

    1992-12-01

    Transit trips-when compared with automobile travel-not only relieve congestion, but also offer considerable energy savings per person. Transit trips also affect land use and development patterns that surround a transit station. In the report, a methodology will be developed to estimate the energy savings associated with land use changes in the station areas. Since changes in land use and development in a station area are partially dependent on the type of service offered (rail versus bus rapid, for example), a classification system will be developed for different types of transit stations, a system based on the land use and development changes that occur within the station's zone of influence.

  16. Making the Transition from Geoscience Geek to Policy Wonk

    NASA Astrophysics Data System (ADS)

    Rowan, L.

    2013-12-01

    Geoscientists are often drawn into policymaking, willingly or otherwise, because mapping a course of action for a specific outcome benefits from geoscientific expertise. Policy development, such as legislation or regulation regarding energy, water, minerals, soils, hazards, land use, and other Earth-based processes, is informed by the geosciences. Some geoscientists have moved fully into policymaking as full time policymakers for congressional offices, government agencies, think tanks, non-profits, foundations, industry, and other places. Geoscientists turned policymakers need good communication skills, patience, persistence, strategic forethought, agility, timing, an understanding of competing interests, and the courage to advance geoscientifically sound policy with the right people at the right time. Transitioning from the geeky world of geoscience to the wonky world of policy for a brief time or full time is possible, can be fulfilling as well as frustrating, and ultimately can have a profound impact on how society adapts to living with a dynamic Earth.

  17. Helping Rural Adolescents Make Successful Postsecondary Transitions: A Longitudinal Study

    ERIC Educational Resources Information Center

    Lapan, Richard T.; Aoyagi, Mark; Kayson, Marc

    2007-01-01

    The longitudinal study in this article tested whether advantages in the career development of high school seniors resulted in better transition outcomes for these young adults 3 years after they graduated from high school. Enhanced career development in high school was significantly connected to more successful transitions into the adult roles of…

  18. Parallel Transitions in IT Outsourcing: Making It Happen

    NASA Astrophysics Data System (ADS)

    Beulen, Erik; Tiwari, Vinay

    Global sourcing of IT services is growing consistently over the last decades. Along with this rapid growth, instances of failures, sore relationships or unsatisfactory performances during IT outsourcing engagements are prevalent and require management attention. Over two-thirds of the problems in these unsuccessful engagements arise due to failed or poor transition. Transition is immediately followed by contract signing and precedes service delivery phase. It sets the tone for the entire relationship and involves handover of outsourced services from either the client's internal IT department or the incumbent service provider. Recently second and third generation outsourcing engagements are coming into existence, with offshoring and multi-sourcing as an integral component of these engagements. Multi-sourcing deals, involving several service providers are emerging and require transition to be implemented in parallel. These developments exacerbate the complexity of transitions due to the presence of multiple service providers and several distributed or offshore locations, thereby further enhancing its bearing on the success of an engagement. What are the Critical Success Factors for parallel transitions? We conducted an initial Delphi study to explore success factors for parallel transitions. The findings highlight the importance of understanding the contractual agreement including transition exit criteria. Also the implementation of a joint steering committee contributes to transition success. All the stakeholders, including representatives of the incumbent service provider(s), should be represented in the steering committee to act responsive. Finally, the findings emphasis the need to manage dependencies between the transitions not limited to time lines and availability of critical resources for knowledge transfer and balancing between business continuity and timely and effective knowledge transfer.

  19. Making a Meaningful Connection--Freshman Transition and Service-Learning

    ERIC Educational Resources Information Center

    Dedmond, Rebecca M.; Kestler, Erin T.

    2010-01-01

    Student engagement is an essential part of the many transitions adolescents must make on their way to self-sufficient adulthood. Motivating students to learn at pivotal points in their school careers, especially as they transition into high school, is sometimes difficult. The Freshman Transition Initiative (FTI) at The George Washington University…

  20. Enhancing Linkages to Postsecondary Education: Helping Youths Make a Successful Transition to College.

    ERIC Educational Resources Information Center

    Bragg, Debra D.

    1999-01-01

    Many more of the nation's youths deserve the opportunity to make the transition from school to college, casting the net of postsecondary education more widely and equitably. The necessity of encouraging more youths to participate in rigorous academics so they are ready to make a smooth transition to college has been recognized for some time. In…

  1. Learning in Global Settings: Developing Transitions for Meaning-Making

    ERIC Educational Resources Information Center

    Norden, Birgitta; Avery, Helen; Anderberg, Elsie

    2012-01-01

    Global teaching and learning for sustainable development reaches from the classroom to the world outside, and is therefore a particularly interesting setting for practising transition skills. The article suggests a number of features perceived as crucial in developing young people's capability to act in a changing world and under circumstances…

  2. Making the Transition to Hospice: Exploring Hospice Professionals' Perspectives

    ERIC Educational Resources Information Center

    Waldrop, Deborah P.; Rinfrette, Elaine S.

    2009-01-01

    Hospice care is available for 6 months before death but the length of use varies widely, suggesting that there are different perspectives on the appropriate timing for this transition. This qualitative study explored hospice professionals' views on the appropriate timing for and communication about hospice. Ethnography of team meetings informed…

  3. Making the Transition from Preschool to Infant/Toddler Teacher.

    ERIC Educational Resources Information Center

    Keenan, Marjory

    1998-01-01

    Draws on discussions with child care workers to discuss important changes involved in moving from teaching preschoolers to teaching infants and toddlers. Describes differences in (1) relating to children; (2) parent/teacher relationships; (3) group dynamics; (4) curriculum; (5) routines and transitions; (6) coworker relationships; (7) director…

  4. Making the Transition from Classical to Quantum Physics

    ERIC Educational Resources Information Center

    Dutt, Amit

    2011-01-01

    This paper reports on the nature of the conceptual understandings developed by Year 12 Victorian Certificate of Education (VCE) physics students as they made the transition from the essentially deterministic notions of classical physics, to interpretations characteristic of quantum theory. The research findings revealed the fact that the…

  5. Wind-Energy Education: Making Paper Windmills

    NASA Astrophysics Data System (ADS)

    Tsubota, Y.; Takasaki, A.

    2009-09-01

    Wind is a limitless source of energy. Large wind turbines such as the familiar 100 meter propeller-type generators are the symbols of environmental consciousness. The wind turbine (i.e., the 'windmill') is a key element in wind energy use. Students use paper models to learn about the types of windmills. The oldest known windmill is a Persian windmill of Panemone design that has a vertical axle containing four to eight fabric sails. Holland is famous for using windmills to harnessing wind energy for milling grain into flour; hence the term 'mill' in 'windmill'. Each type of windmill is designed and used for different purposes. Multi-braded windmills are used to pump aquifers in western America; whereas the sail-wing type windmills are popular throughout the Mediterranean. We teach the benefits of specific windmill designs using paper models. We have developed more than ten different types of paper windmills. First, they are classified into horizontal- versus vertical-axis windmills. Second, they may be classified into lift- versus drag-force type. Third, we may classify windmills by their objectives; such as to generate electric power, to pump aquifers, to milling grain or to cut timber. Students learn the characteristics of each windmill type by making and rotating paper models. Students will find that the 'ease of rotation' depends on the type of windmill; and why a windmill does rotate and how we harness the wind. There are several hidden curriculums for students. First, they will develop their basic modeling skills such as cutting and gluing; Second, they will use their artistic sense to color the windmill; and third, they will learn about windmills' history and their impact on society. Spinning windmills are also entertaining to students. In our workshop, participants will make several kinds of windmill models and experience our proposed wind-energy lessons.

  6. Aspects of energy transitions: History and determinants

    NASA Astrophysics Data System (ADS)

    O'Connor, Peter A.

    Energy intensity in the U.S. from 1780 to 2010 shows a declining trend when traditional energy is included, in contrast to the "inverted U-curve" seen when only commercial energy is considered. The analysis quantifies use of human and animal muscle power, wind and water power, biomass, harvested ice, fossil fuels, and nuclear power. Historical prices are provided for many energy resources. The analysis reaffirms the importance of innovation in conversion technologies in energy transitions. An increase in energy intensity in the early 20th century is explained by diminishing returns to pre-electric manufacturing systems, which produced a transformation in manufacturing. In comparison to similar studies for other countries, the U.S. has generally higher energy intensity. A population-weighted series of heating degree days and cooling degree days partially explains differences in energy intensity. Series are developed for 231 countries and territories with multiple reference temperatures, with a "wet-bulb" series accounting for the effects of humidity. Other variables considered include energy prices, income per capita, and governance indices. A panel regression of thirty-two countries from 1995 to 2010 establishes GDP per capita and share of primary energy as determinants of energy intensity, but fails to establish statistical significance of the climate variables. A group mean regression finds average heating and cooling degree days to be significant predictors of average energy intensity over the study period, increasing energy intensity by roughly 1.5 kJ per 2005 international dollar for each annual degree day. Group mean regression results explain differences in countries' average energy intensity, but not changes within a country over time. Energy Return on Investment (EROI) influences the economic competitiveness and environmental impacts of an energy resource and is one driver of energy transitions. The EROI of U.S. petroleum production has declined since 1972

  7. Transitions.

    ERIC Educational Resources Information Center

    Field, David; And Others

    1992-01-01

    Includes four articles: "Career Aspirations" (Field); "Making the Transition to a New Curriculum" (Baker, Householder); "How about a 'Work to School' Transition?" (Glasberg); and "Technological Improvisation: Bringing CNC to Woodworking" (Charles, McDuffie). (SK)

  8. A transitioning universe with anisotropic dark energy

    NASA Astrophysics Data System (ADS)

    Yadav, Anil Kumar

    2016-08-01

    In this paper, we present a model of transitioning universe with minimal interaction between perfect fluid and anisotropic dark energy in Bianchi I space-time. The two sources are assumed to minimally interacted and therefore their energy momentum tensors are conserved separately. The explicit expression for average scale factor are considered in hybrid form that gives time varying deceleration parameter which describes both the early and late time physical features of universe. We also discuss the physical and geometrical properties of the model derived in this paper. The solution is interesting physically as it explain accelerating universe as well as singularity free universe.

  9. Transitions from Temporary to Permanent Work in Canada: Who Makes the Transition and Why?

    ERIC Educational Resources Information Center

    Fang, Tony; MacPhail, Fiona

    2008-01-01

    The focus of this paper is on a microeconomic analysis of the annual transition rate from temporary to permanent work of individual workers in Canada for the period 1999-2004. Given that a large proportion of temporary employment is involuntary, an understanding of the factors associated with the transition to permanent work may inform public…

  10. I Make a Difference: Making the Transition from Clinician to Educator!

    ERIC Educational Resources Information Center

    Hudson, Larry, Ed.; And Others

    Intended for the vocational health occupations (VHO) teacher during the transition from clinician to teacher, this practical handbook offers advice on bridging the gap between practice and teaching. Chapter 1 addresses defining one's new role. Chapter 2 on classroom instruction looks at student motivation, teaching techniques, student feedback,…

  11. Making an Energy Conservation Program Work.

    ERIC Educational Resources Information Center

    Rump, Erwin E.; Hunter, James L.

    The first step of an energy conservation program is to monitor energy consumption. A system is explained that, in order to determine which buildings are energy efficient (considering all types of energy that a building might use), monitors total energy consumption. All such consumptions can be reduced to a common denominator: Barrels of Energy…

  12. From Scripted Instruction to Teacher Empowerment: Supporting Literacy Teachers to Make Pedagogical Transitions

    ERIC Educational Resources Information Center

    Fang, Zhihui; Fu, Danling; Lamme, Linda Leonard

    2004-01-01

    The article describes a longitudinal professional development project in rural Florida (USA) schools that supports the efforts of inservice teachers to make pedagogical transitions from total reliance on prepackaged commercial programmes to making informed decisions about curriculum and pedagogy autonomously. It demonstrates that in order to…

  13. Get Started: Energy Efficiency Makes More Sense Than Ever.

    ERIC Educational Resources Information Center

    Alban, Josh; Drabick, J. R.

    2003-01-01

    Describes the benefits of making school building more energy efficient. Provides examples of physical retrofits and behavioral changes to save energy costs. Describes four-step process to create an energy efficiency plan. Includes resources and information such as U.S. Department of Energy's Energy STAR program (www.energystar.gov). (PKP)

  14. Making More Light with Less Energy

    SciTech Connect

    Kuritzky, Leah; Jewell, Jason

    2013-07-18

    Representing the Center for Energy Efficient Materials (CEEM), this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE: energy. The mission of the CEEM is to discover and develop materials that control the interactions among light, electricity, and heat at the nanoscale for improved solar energy conversion, solid-state lighting, and conversion of heat into electricity.

  15. Making the Most of Waste Energy

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The Thermo-Mechanical Systems Branch at NASA s Glenn Research Center is responsible for planning and conducting research efforts to advance thermal systems for space, aerospace, and non-aerospace applications. Technological areas pertain to solar and thermal energy conversion. For example, thermo-mechanical systems researchers work with gas (Stirling) and liquid/vapor (Rankine) systems that convert thermal energy to electrical power, as well as solar dynamic power systems that concentrate sunlight to electrical power. The branch s development of new solar and thermal energy technologies is propelling NASA s missions deep into unfamiliar territories of space. Solar dynamic power systems are actively improving the health of orbiting satellites, giving them longer life and a stronger radiation tolerance, thus, creating less need for on-orbit maintenance. For future missions, NASA may probe even deeper into the mysterious cosmos, with the adoption of highly efficient thermal energy converters that have the potential to serve as the source of onboard electrical power for satellites and spacecraft. Research indicates that these thermal converters can deliver up to 5 times as much power as radioisotope thermoelectric generators in use today, for the same amount of radioisotope. On Earth, energy-converting technologies associated with NASA s Thermo-Mechanical Systems Branch are being used to recover and transform low-temperature waste heat into usable electric power, with a helping hand from NASA.

  16. Using Left Overs to Make Energy

    SciTech Connect

    Steuterman, Sally; Czarnecki, Alicia; Hurley, Paul; Peruski, Kathryn; Cartagena-Sierra, Alejandra; Evans, Isaac; Guzman, Alexis

    2013-07-18

    Representing the Material Science Antinides (MSA), this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE energy. The mission of MSA is to conduct transformative research in the actinide sciences with full integration of experimental and computational approaches, and an emphasis on research questions that are important to the energy future of the nation.

  17. Making the right energy choices in America

    SciTech Connect

    Meyers, E.M.

    1993-07-15

    This article discusses the need for convincing consumers, especially residential customers, to consume less electricity. A two-part method for achieving this is discussed. The first part consists of discounted energy efficiency rates. Structures using less than a predetermined amount of electricity would qualify for lower rates. The second part consists of a conservation ethic. This entails a public awareness program to show people the consequences of wasteful energy use, and the benefits of such things as insulation and fans. Some examples of actual programs are given for both approaches.

  18. The Relationship between Moral Decision Making and Patterns of Consolidation and Transition in Moral Judgment Development.

    ERIC Educational Resources Information Center

    Thoma, Stephen J.; Rest, James R.

    1999-01-01

    Assessed the relationship between a measure of consolidation and transition in moral-judgment development and utility of moral concepts in sociomoral decision making in multiple cross-sectional and longitudinal samples. Found that participants' reliance on a Kohlbergian moral framework was highest during periods of consolidation and lowest during…

  19. Making the Transition to Teaching Online: Strategies and Methods for the First-Time, Online Instructor.

    ERIC Educational Resources Information Center

    VanSickle, Jennifer

    This paper discusses the changes in instruction needed to make the transition to teaching an online course. It discusses both traditional and alternative teaching methods a first-time online instructor might choose to use. The advantages and disadvantages of online courses are explored through a review of the literature, and ways in which online…

  20. A Career in Professional Athletics: A Guide for Making the Transition.

    ERIC Educational Resources Information Center

    Bolig, Laura E., Ed.

    This booklet provides guidance to student-athletes on making the transition to a career in professional athletics. It contains a list of do's and don'ts for students in regard to their collegiate eligibility, along with suggestions on obtaining disability insurance coverage for protection from loss of future earnings. The booklet provides…

  1. Local energy governance in vermont: an analysis of energy system transition strategies and actor capacity

    NASA Astrophysics Data System (ADS)

    Rowse, Tarah

    While global, national, and regional efforts to address climate and energy challenges remain essential, local governments and community groups are playing an increasingly stronger and vital role. As an active state in energy system policy, planning and innovation, Vermont offers a testing ground for research into energy governance at the local level. A baseline understanding of the energy planning and energy organizing activities initiated at the local level can support efforts to foster a transition to a sustainable energy system in Vermont. Following an inductive, applied and participatory approach, and grounded in the fields of sustainability transitions, energy planning, and community energy, this research project identifies conditions for change, including opportunities and challenges, within Vermont energy system decision-making and governance at the local level. The following questions are posed: What are the main opportunities and challenges for sustainable energy development at the town level? How are towns approaching energy planning? What are the triggers that will facilitate a faster transition to alternative energy systems, energy efficiency initiatives, and localized approaches? In an effort to answer these questions two studies were conducted: 1) an analysis of municipal energy plans, and 2) a survey of local energy actors. Study 1 examined Vermont energy planning at the state and local level through a review and comparison of 40 municipal plan energy chapters with the state 2011 Comprehensive Energy Plan. On average, municipal plans mentioned just over half of the 24 high-level strategies identified in the Comprehensive Energy Plan. Areas of strong and weak agreement were examined. Increased state and regional interaction with municipal energy planners would support more holistic and coordinated energy planning. The study concludes that while municipalities are keenly aware of the importance of education and partnerships, stronger policy mechanisms

  2. Near-optimal energy transitions for energy-state trajectories of hypersonic aircraft

    NASA Astrophysics Data System (ADS)

    Ardema, M. D.; Bowles, J. V.; Terjesen, E. J.; Whittaker, T.

    1992-08-01

    A problem of the instantaneous energy transition that occurs in energy-state approximation is considered. The transitions are modeled as a sequence of two load-factor bounded paths (either climb-dive or dive-climb). The boundary-layer equations associated with the energy-state dynamic model are analyzed to determine the precise location of the transition.

  3. Photoinduced energy transfer in transition metal complex oligomers

    SciTech Connect

    1997-06-01

    The work done over the past three years has been directed toward the preparation, characterization and photophysical examination of mono- and bimetallic diimine complexes. The work is part of a broader project directed toward the development of stable, efficient, light harvesting arrays of transition metal complex chromophores. One focus has been the synthesis of rigid bis-bidentate and bis-tridentate bridging ligands. The authors have managed to make the ligand bphb in multigram quantities from inexpensive starting materials. The synthetic approach used has allowed them to prepare a variety of other ligands which may have unique applications (vide infra). They have prepared, characterized and examined the photophysical behavior of Ru(II) and Re(I) complexes of the ligands. Energy donor/acceptor complexes of bphb have been prepared which exhibit nearly activationless energy transfer. Complexes of Ru(II) and Re(I) have also been prepared with other polyunsaturated ligands in which two different long lived (> 50 ns) excited states exist; results of luminescence and transient absorbance measurements suggest the two states are metal-to-ligand charge transfer and ligand localized {pi}{r_arrow}{pi}* triplets. Finally, the authors have developed methods to prepare polymetallic complexes which are covalently bound to various surfaces. The long term objective of this work is to make light harvesting arrays for the sensitization of large band gap semiconductors. Details of this work are provided in the body of the report.

  4. Photoinduced energy transfer in transition metal complex oligomers

    SciTech Connect

    1997-04-01

    The work we have done over the past three years has been directed toward the preparation, characterization and photophysical examination of mono- and bimetallic diimine complexes. The work is part of a broader project directed toward the development of stable, efficient, light harvesting arrays of transition metal complex chromophores. One focus has been the synthesis of rigid bis-bidentate and bis-tridentate bridging ligands. We have managed to make the ligand bphb in multigram quantities from inexpensive starting materials. The synthetic approach used has allowed us prepare a variety of other ligands which may have unique applications (vide infra). We have prepared, characterized and examined the photophysical behavior of Ru(II) and Re(I) complexes of the ligands. Energy donor/acceptor complexes of bphb have been prepared which exhibit nearly activationless energy transfer. Complexes of Ru(II) and Re(I) have also been prepared with other polyunsaturated ligands in which two different long lived ( > 50 ns) excited states exist; results of luminescence and transient absorbance measurements suggest the two states are metal-to-ligand charge transfer and ligand localized {pi}{r_arrow}{pi}* triplets. Finally, we have developed methods to prepare polymetallic complexes which are covalently bound to various surfaces. The long term objective of this work is to make light harvesting arrays for the sensitization of large band gap semiconductors. Details of this work are provided in the body of the report.

  5. Urban decision making for transportation investments: Portland's light-rail transit system. Final report

    SciTech Connect

    Edner, S.M.; Arrington, G.B.

    1985-03-01

    This report is a detailed case study of the various decisions which led to the investment in Portland, Oregon's light-rail transit system. The study reviews the alternatives that were considered, the factors that led to the choices made, and the impacts and secondary effects the choices triggered. Topics discussed include the withdrawal of the Mount Hood Freeway, the substitution of transit and the options considered, the changing political infrastructure that affected decision making, citizen participation in the process, financing of the system, involvement of the private sector downtown, and the actual building of the light-rail line. The report should be of special interest to staffs of local officials involved in making major transportation investment decisions.

  6. Make Energy at the Bay Area Maker Faire

    ScienceCinema

    None

    2016-07-12

    Think. Make. Innovate. A festival of invention, creativity and resourcefulness that gathers makers of all kinds. Scientists are seeking to find innovative solutions to the energy challenges in the world.

  7. Optimal strategies for electric energy contract decision making

    NASA Astrophysics Data System (ADS)

    Song, Haili

    2000-10-01

    The power industry restructuring in various countries in recent years has created an environment where trading of electric energy is conducted in a market environment. In such an environment, electric power companies compete for the market share through spot and bilateral markets. Being profit driven, electric power companies need to make decisions on spot market bidding, contract evaluation, and risk management. New methods and software tools are required to meet these upcoming needs. In this research, bidding strategy and contract pricing are studied from a market participant's viewpoint; new methods are developed to guide a market participant in spot and bilateral market operation. A supplier's spot market bidding decision is studied. Stochastic optimization is formulated to calculate a supplier's optimal bids in a single time period. This decision making problem is also formulated as a Markov Decision Process. All the competitors are represented by their bidding parameters with corresponding probabilities. A systematic method is developed to calculate transition probabilities and rewards. The optimal strategy is calculated to maximize the expected reward over a planning horizon. Besides the spot market, a power producer can also trade in the bilateral markets. Bidding strategies in a bilateral market are studied with game theory techniques. Necessary and sufficient conditions of Nash Equilibrium (NE) bidding strategy are derived based on the generators' cost and the loads' willingness to pay. The study shows that in any NE, market efficiency is achieved. Furthermore, all Nash equilibria are revenue equivalent for the generators. The pricing of "Flexible" contracts, which allow delivery flexibility over a period of time with a fixed total amount of electricity to be delivered, is analyzed based on the no-arbitrage pricing principle. The proposed algorithm calculates the price based on the optimality condition of the stochastic optimization formulation

  8. Substituent effect on electronic transition energy of dichlorobenzyl radicals

    NASA Astrophysics Data System (ADS)

    Yoon, Young Wook; Chae, Sang Youl; Lee, Sang Kuk

    2016-01-01

    Ring-substituted benzyl radicals exhibit electronic energies of the D1 → D0 transition being shifted to red region with respect to the benzyl radical. The red-shifts of disubstituted benzyl radicals are highly dependent on the substitution positions irrespective of substituents. By analyzing the red-shifts of dichlorobenzyl radicals observed, we found that the substituent effect on electronic transition energy is attributed to the molecular plane shape of delocalized π electrons. We will discuss the influences of locations of Cl substituents on the D1 → D0 transition energies of dichlorobenzyl radicals using Hückel's molecular orbital theory.

  9. Trends in Ionization Energy of Transition-Metal Elements

    ERIC Educational Resources Information Center

    Matsumoto, Paul S.

    2005-01-01

    A rationale for the difference in the periodic trends in the ionization energy of the transition-metal elements versus the main-group elements is presented. The difference is that in the transition-metal elements, the electrons enter an inner-shell electron orbital, while in the main-group elements, the electrons enter an outer-shell electron…

  10. Energy Released During the H-L Back Transition

    NASA Astrophysics Data System (ADS)

    Eldon, D.; Kolemen, E.; Gohil, P.; McKee, G. R.; Yan, Z.; Schmitz, L.

    2015-11-01

    Prompt energy loss (ΔW) at the H-L transition, as a fraction of total stored energy before the transition, is about 30 % and is insensitive to density in ITER-similar DIII-D plasmas. Occasionally, some ELMs will appear before the transition and reduce total energy, thus reducing ΔW across the following transition. Other results (not in the ITER-similar shape) have shown that ELMs can be triggered in low powered H-modes, prior to H-L transitions, when the plasma is stable to ideal P-B modes (these are not typical type-I ELMs, despite superficial similarities) and E × B shear is strong. These are indeed ELMs occurring in H-mode and not part of a dithering transition. Finally, ELM ΔW is sensitive to edge toroidal rotation and becomes smaller than uncertainty (< 5 kJ) at low rotation (ωtor < 5 krad/s). These results point to a strategy where ΔW for the H-L transition may be reduced by the presence of (not type-I) ELMs before the transition, and ΔW for the ELMs may be reduced by controlling rotation. Work supported by the US Department of Energy under DE-AC02-09CH11466 and DE-FC02-04ER54698.

  11. Energy and Society: Investigations in Decision Making. [Student Manual].

    ERIC Educational Resources Information Center

    Biological Sciences Curriculum Study, Boulder, CO.

    This publication is the student handbook for a BSCS energy education module designed for high school, college, and adult students. It is designed to provide students with information about energy that will help them make decisions as citizens. Basically, this document is a text to supplement the activities and lesson plans in the teacher's guide.…

  12. Hybrid radical energy storage device and method of making

    DOEpatents

    Gennett, Thomas; Ginley, David S; Braunecker, Wade; Ban, Chunmei; Owczarczyk, Zbyslaw

    2015-01-27

    Hybrid radical energy storage devices, such as batteries or electrochemical devices, and methods of use and making are disclosed. Also described herein are electrodes and electrolytes useful in energy storage devices, for example, radical polymer cathode materials and electrolytes for use in organic radical batteries.

  13. Hybrid radical energy storage device and method of making

    DOEpatents

    Gennett, Thomas; Ginley, David S.; Braunecker, Wade; Ban, Chunmei; Owczarczyk, Zbyslaw

    2016-04-26

    Hybrid radical energy storage devices, such as batteries or electrochemical devices, and methods of use and making are disclosed. Also described herein are electrodes and electrolytes useful in energy storage devices, for example, radical polymer cathode materials and electrolytes for use in organic radical batteries.

  14. [Relationships between settlement morphology transition and residents commuting energy consumption].

    PubMed

    Zhou, Jian; Xiao, Rong-Bo; Sun, Xiang

    2013-07-01

    Settlement morphology transition is triggered by rapid urbanization and urban expansion, but its relationships with residents commuting energy consumption remains ambiguous. It is of significance to understand the controlling mechanisms of sustainable public management policies on the energy consumption and greenhouse gases emission during the process of urban settlement morphology transition. Taking the Xiamen City of East China as a case, and by using the integrated land use and transportation modeling system TRANUS, a scenario analysis was made to study the effects of urban settlement morphology transition on the urban spatial distribution of population, jobs, and land use, and on the residents commuting energy consumption and greenhouse gasses emission under different scenarios. The results showed that under the Business As Usual (BAU) scenario, the energy consumption of the residents at the morning peak travel time was 54.35 tce, and the CO2 emission was 119.12 t. As compared with those under BAU scenario, both the energy consumption and the CO2 emission under the Transition of Settlement Morphology (TSM) scenario increased by 12%, and, with the implementation of the appropriate policies such as land use, transportation, and economy, the energy consumption and CO2 emission under the Transition of Settlement Morphology with Policies (TSMP) scenario reduced by 7%, indicating that urban public management policies could effectively control the growth of residents commuting energy consumption and greenhouse gases emission during the period of urban settlement morphology transition.

  15. Energy level transitions of gas in a 2D nanopore

    SciTech Connect

    Grinyaev, Yurii V.; Chertova, Nadezhda V.; Psakhie, Sergei G.

    2015-10-27

    An analytical study of gas behavior in a 2D nanopore was performed. It is shown that the temperature dependence of gas energy can be stepwise due to transitions from one size-quantized subband to another. Taking into account quantum size effects results in energy level transitions governed by the nanopore size, temperature and gas density. This effect leads to an abrupt change of gas heat capacity in the nanopore at the above varying system parameters.

  16. DOE-HUD Initiative: Making Housing Affordable Through Energy Efficiency

    SciTech Connect

    Not Available

    1991-10-01

    A new collaborative program of the U.S. Department of Energy (DOE) and the U.S. Department of Housing and Urban Development (HUD) is a significant step toward making HUD-aided housing more comfortable and affordable through greater energy efficiency. The initiative on Energy Efficiency in Housing combines DOE's technical capabilities and HUD's experience in housing assistance. Over the next decade, the energy savings potential of this initiative is estimated to be 150 trillion Btu (0.15 quad) per year, or nearly $1.5 billion in annual energy costs.

  17. Irrational decision-making in an amoeboid organism: transitivity and context-dependent preferences.

    PubMed

    Latty, Tanya; Beekman, Madeleine

    2011-01-22

    Most models of animal foraging and consumer choice assume that individuals make choices based on the absolute value of items and are therefore 'economically rational'. However, frequent violations of rationality by animals, including humans, suggest that animals use comparative valuation rules. Are comparative valuation strategies a consequence of the way brains process information, or are they an intrinsic feature of biological decision-making? Here, we examine the principles of rationality in an organism with radically different information-processing mechanisms: the brainless, unicellular, slime mould Physarum polycephalum. We offered P. polycephalum amoebas a choice between food options that varied in food quality and light exposure (P. polycephalum is photophobic). The use of an absolute valuation rule will lead to two properties: transitivity and independence of irrelevant alternatives (IIA). Transitivity is satisfied if preferences have a consistent, linear ordering, while IIA states that a decision maker's preference for an item should not change if the choice set is expanded. A violation of either of these principles suggests the use of comparative rather than absolute valuation rules. Physarum polycephalum satisfied transitivity by having linear preference rankings. However, P. polycephalum's preference for a focal alternative increased when a third, inferior quality option was added to the choice set, thus violating IIA and suggesting the use of a comparative valuation process. The discovery of comparative valuation rules in a unicellular organism suggests that comparative valuation rules are ubiquitous, if not universal, among biological decision makers.

  18. Rail transit energy management program: Energy database. Volume 2. Final report

    SciTech Connect

    Uher, R.A.

    1995-03-01

    The Rail Transportation Energy Management Program (EMP) is a private/public partnership whose objective is to reduce rail transit energy cost and improve energy efficiency. The Energy Database (EDB) was set up under the program. The purpose of the EDB is to provide information to the members of the program. This information includes rail transit energy and energy cost data and the results of implementation of energy cost reduction strategies. The EDB also includes a means for timely exchange of information among transit authorities as well as associated with energy management. The database is presently set up on a personal computer and is accessed by the users via an 800 telephone line.

  19. Battery energy storage for rail transit systems. Technical report

    SciTech Connect

    Uher, R.A.

    1996-04-01

    A battery simulation model was developed to work in conjunction with the Rail Transit Energy Management Model (EMM) to estimate the performance of battery energy storage on rail transit systems. This model uses a battery which is connected directly to the DC bus at a substation. No power conditioning equipment is involved, thus reducing the cost of a battery station substantially. Although these types of battery stations could be used for peak load shaving, voltage boost, and increasing energy receptivity on a system with regenerating trains, it was found that the last of these uses proved economically feasible. Because energy receptivity is increased, the peak load will also be shaved.

  20. Moving from situational awareness to decisions during disaster response: transition to decision making.

    PubMed

    Glick, Jeffrey A; Barbara, Joseph A

    2013-01-01

    During major disasters, at what point in the decisional process do senior government officials transition from developing necessary situational awareness to perform decision making? This "transition to decision making" (TDM) concept was analyzed through a structured interview survey of 25 current and former US Federal Coordinating Officers (FCOs) and focused on their decision-making process during the initial response period in a Presidentially declared Stafford Act disaster. This analysis suggests that the TDM for these emergency leaders is influenced by the following five factors: 1) Analogue Factor: the decision maker's previous knowledge and experience from analogous disaster situations; 2) New Paradigm Factor: the degree to which the disaster situation is very atypical to the decision maker due to hazard type and or situation severity, 3) Data Capture Factor: the quality, amount, and speed of disaster situation data conveyed to the decision maker; 4) Data Integration Factor: the decision maker's ability to integrate situational data elements into a mental framework picture; and 5) Time Urgency Factor: the decision maker's perception as to time available before a decision has to be made. The article describes the factors and graphs that how these may influence the timing of the TDM in four types of emergency situations faced by FCOs: 1) an analogue disaster, 2) a disaster situation that presents a new paradigm, 3) an intuitive disaster situation, and 4) a disaster requiring an urgent response.

  1. Minimum energy paths of wetting transitions on grooved surfaces.

    PubMed

    Pashos, George; Kokkoris, George; Boudouvis, Andreas G

    2015-03-17

    A method that computes minimum energy paths (MEPs) of wetting transitions is developed. The method couples the Cahn-Hilliard formulation of a modified phase-field method with the simplified string method. Its main computational kernel is the fast Fourier transform that is efficiently performed on graphics processing units. The effectiveness of the proposed method is demonstrated on two types of transitions of droplets on grooved surfaces. The first is the transition from the Cassie-Baxter wetting state to the Wenzel state, where it is shown that it progresses in a sequential manner with the droplet wetting each groove successively. The second transition type is a lateral displacement of the droplet against the grooves, where the droplet successively detaches/attaches from/to the rear/front protrusion of the surface (a transition in the reverse order is also possible). The energy barriers of both the transitions are extracted from the MEP; they are useful for the evaluation of the robustness of superhydrophobic surfaces (resistance to the Cassie-Baxter to Wenzel transition) and the droplet mobility on those surfaces (high mobility/small resistance to lateral displacements). The relation of the MEP with the potential transition paths coming from the solution space mapping is discussed. PMID:25715270

  2. Understanding the human dimensions of a sustainable energy transition

    PubMed Central

    Steg, Linda; Perlaviciute, Goda; van der Werff, Ellen

    2015-01-01

    Global climate change threatens the health, economic prospects, and basic food and water sources of people. A wide range of changes in household energy behavior is needed to realize a sustainable energy transition. We propose a general framework to understand and encourage sustainable energy behaviors, comprising four key issues. First, we need to identify which behaviors need to be changed. A sustainable energy transition involves changes in a wide range of energy behaviors, including the adoption of sustainable energy sources and energy-efficient technology, investments in energy efficiency measures in buildings, and changes in direct and indirect energy use behavior. Second, we need to understand which factors underlie these different types of sustainable energy behaviors. We discuss three main factors that influence sustainable energy behaviors: knowledge, motivations, and contextual factors. Third, we need to test the effects of interventions aimed to promote sustainable energy behaviors. Interventions can be aimed at changing the actual costs and benefits of behavior, or at changing people’s perceptions and evaluations of different costs and benefits of behavioral options. Fourth, it is important to understand which factors affect the acceptability of energy policies and energy systems changes. We discuss important findings from psychological studies on these four topics, and propose a research agenda to further explore these topics. We emphasize the need of an integrated approach in studying the human dimensions of a sustainable energy transition that increases our understanding of which general factors affect a wide range of energy behaviors as well as the acceptability of different energy policies and energy system changes. PMID:26136705

  3. Understanding the human dimensions of a sustainable energy transition.

    PubMed

    Steg, Linda; Perlaviciute, Goda; van der Werff, Ellen

    2015-01-01

    Global climate change threatens the health, economic prospects, and basic food and water sources of people. A wide range of changes in household energy behavior is needed to realize a sustainable energy transition. We propose a general framework to understand and encourage sustainable energy behaviors, comprising four key issues. First, we need to identify which behaviors need to be changed. A sustainable energy transition involves changes in a wide range of energy behaviors, including the adoption of sustainable energy sources and energy-efficient technology, investments in energy efficiency measures in buildings, and changes in direct and indirect energy use behavior. Second, we need to understand which factors underlie these different types of sustainable energy behaviors. We discuss three main factors that influence sustainable energy behaviors: knowledge, motivations, and contextual factors. Third, we need to test the effects of interventions aimed to promote sustainable energy behaviors. Interventions can be aimed at changing the actual costs and benefits of behavior, or at changing people's perceptions and evaluations of different costs and benefits of behavioral options. Fourth, it is important to understand which factors affect the acceptability of energy policies and energy systems changes. We discuss important findings from psychological studies on these four topics, and propose a research agenda to further explore these topics. We emphasize the need of an integrated approach in studying the human dimensions of a sustainable energy transition that increases our understanding of which general factors affect a wide range of energy behaviors as well as the acceptability of different energy policies and energy system changes.

  4. Understanding the human dimensions of a sustainable energy transition.

    PubMed

    Steg, Linda; Perlaviciute, Goda; van der Werff, Ellen

    2015-01-01

    Global climate change threatens the health, economic prospects, and basic food and water sources of people. A wide range of changes in household energy behavior is needed to realize a sustainable energy transition. We propose a general framework to understand and encourage sustainable energy behaviors, comprising four key issues. First, we need to identify which behaviors need to be changed. A sustainable energy transition involves changes in a wide range of energy behaviors, including the adoption of sustainable energy sources and energy-efficient technology, investments in energy efficiency measures in buildings, and changes in direct and indirect energy use behavior. Second, we need to understand which factors underlie these different types of sustainable energy behaviors. We discuss three main factors that influence sustainable energy behaviors: knowledge, motivations, and contextual factors. Third, we need to test the effects of interventions aimed to promote sustainable energy behaviors. Interventions can be aimed at changing the actual costs and benefits of behavior, or at changing people's perceptions and evaluations of different costs and benefits of behavioral options. Fourth, it is important to understand which factors affect the acceptability of energy policies and energy systems changes. We discuss important findings from psychological studies on these four topics, and propose a research agenda to further explore these topics. We emphasize the need of an integrated approach in studying the human dimensions of a sustainable energy transition that increases our understanding of which general factors affect a wide range of energy behaviors as well as the acceptability of different energy policies and energy system changes. PMID:26136705

  5. The carbon-consuming home: residential markets and energy transitions.

    PubMed

    Jones, Christopher

    2011-01-01

    Home heating and lighting markets have played crucial and underappreciated roles in driving energy transitions. When historians have studied the adoption of fossil fuels, they have often privileged industrial actors, markets, and technologies. My analysis of the factors that stimulated the adoption of anthracite coal and petroleum during the nineteenth century reveals that homes shaped how, when, and why Americans began to use fossil fuel energy. Moreover, a brief survey of other fossil fuel transitions shows that heating and lighting markets have been critical drivers in other times and places. Reassessing the historical patterns of energy transitions offers a revised understanding of the past for historians and suggests a new set of options for policymakers seeking to encourage the use of renewable energy in the future.

  6. The carbon-consuming home: residential markets and energy transitions.

    PubMed

    Jones, Christopher

    2011-01-01

    Home heating and lighting markets have played crucial and underappreciated roles in driving energy transitions. When historians have studied the adoption of fossil fuels, they have often privileged industrial actors, markets, and technologies. My analysis of the factors that stimulated the adoption of anthracite coal and petroleum during the nineteenth century reveals that homes shaped how, when, and why Americans began to use fossil fuel energy. Moreover, a brief survey of other fossil fuel transitions shows that heating and lighting markets have been critical drivers in other times and places. Reassessing the historical patterns of energy transitions offers a revised understanding of the past for historians and suggests a new set of options for policymakers seeking to encourage the use of renewable energy in the future. PMID:22213886

  7. Reducing fatigue damage for ships in transit through structured decision making

    USGS Publications Warehouse

    Nichols, J.M.; Fackler, P.L.; Pacifici, K.; Murphy, K.D.; Nichols, J.D.

    2014-01-01

    Research in structural monitoring has focused primarily on drawing inference about the health of a structure from the structure’s response to ambient or applied excitation. Knowledge of the current state can then be used to predict structural integrity at a future time and, in principle, allows one to take action to improve safety, minimize ownership costs, and/or increase the operating envelope. While much time and effort has been devoted toward data collection and system identification, research to-date has largely avoided the question of how to choose an optimal maintenance plan. This work describes a structured decision making (SDM) process for taking available information (loading data, model output, etc.) and producing a plan of action for maintaining the structure. SDM allows the practitioner to specify his/her objectives and then solves for the decision that is optimal in the sense that it maximizes those objectives. To demonstrate, we consider the problem of a Naval vessel transiting a fixed distance in varying sea-state conditions. The physics of this problem are such that minimizing transit time increases the probability of fatigue failure in the structural supports. It is shown how SDM produces the optimal trip plan in the sense that it minimizes both transit time and probability of failure in the manner of our choosing (i.e., through a user-defined cost function). The example illustrates the benefit of SDM over heuristic approaches to maintaining the vessel.

  8. Dynamics of Cortical Neuronal Ensembles Transit from Decision Making to Storage for Later Report

    PubMed Central

    Ponce-Alvarez, Adrián; Nácher, Verónica; Luna, Rogelio; Riehle, Alexa

    2012-01-01

    Decisions based on sensory evaluation during single trials may depend on the collective activity of neurons distributed across brain circuits. Previous studies have deepened our understanding of how the activity of individual neurons relates to the formation of a decision and its storage for later report. However, little is known about how decision-making and decision maintenance processes evolve in single trials. We addressed this problem by studying the activity of simultaneously recorded neurons from different somatosensory and frontal lobe cortices of monkeys performing a vibrotactile discrimination task. We used the hidden Markov model to describe the spatiotemporal pattern of activity in single trials as a sequence of firing rate states. We show that the animal's decision was reliably maintained in frontal lobe activity through a selective state sequence, initiated by an abrupt state transition, during which many neurons changed their activity in a concomitant way, and for which both latency and variability depended on task difficulty. Indeed, transitions were more delayed and more variable for difficult trials compared with easy trials. In contrast, state sequences in somatosensory cortices were weakly decision related, had less variable transitions, and were not affected by the difficulty of the task. In summary, our results suggest that the decision process and its subsequent maintenance are dynamically linked by a cascade of transient events in frontal lobe cortices. PMID:22933781

  9. Exchange and relaxation effects in low-energy radiationless transitions

    NASA Technical Reports Server (NTRS)

    Chen, M. H.; Crasemann, B.; Aoyagi, M.; Mark, H.

    1978-01-01

    The effect on low-energy atomic inner-shell Coster-Kronig and super Coster-Kronig transitions that is produced by relaxation and by exchange between the continuum electron and bound electrons was examined and illustrated by specific calculations for transitions that deexcite the 3p vacancy state of Zn. Taking exchange and relaxation into account is found to reduce, but not to eliminate, the discrepancies between theoretical rates and measurements.

  10. Meaning-Making Dynamics of Emancipated Foster Care Youth Transitioning into Higher Education: A Constructivist-Grounded Theory

    ERIC Educational Resources Information Center

    Okumu, Jacob O.

    2014-01-01

    This study explored college transition meaning-making dynamics of emancipated foster care youth and the role campus environments play in that process. It adds to the college student development theoretical base by acknowledging the needs, goals, and values of disenfranchised college students transitioning into higher education. Emancipated foster…

  11. The Developmental Transition from Living with to Dying From Cancer: Hospice Decision-making

    PubMed Central

    Waldrop, Deborah; Meeker, Mary Ann; Kutner, Jean S.

    2016-01-01

    Despite increasing utilization of hospice care, older adults with cancer enroll in hospice for shorter periods of time than those with other life-limiting illnesses. How older adults with cancer and their family members consider hospice is unknown. The purpose of this study was to compare decision-making in late-stage cancer in people who enrolled in hospice with those who declined. Concepts from the Carroll and Johnson (1990) decision-making framework guided the development of a hospice decision-making model. The study design was exploratory-descriptive, cross-sectional and used a 2-group comparison. Qualitative and quantitative data were collected in the same interview. Open-ended questions were used to explore the illness trajectory and decision-making process. The interrelationships between functional ability, quality of life and social support with hospice decision-making were assessed using the Katz, QLQ-30 and Lubben Social Network Scales. Study participants included 42 older adults with cancer who had been offered hospice enrollment (24 non-hospice and 18 hospice) and 38 caregivers (15 non-hospice and 23 hospice); N=80. The decisional model illustrates that the Recognition of Advanced Cancer and Information and Communication Needs were experienced similarly by both groups. There was interaction between the decisional stages: Formulation of Awareness and Generation of Alternatives that informed the Evaluation of Hospice but these stages were different in the hospice and non-hospice groups. The hospice enrollment decision represents a critical developmental juncture which is accompanied by a transformed identity and substantive cognitive shift. Increased attention to the psychosocial and emotional issues that accompany this transition are important for quality end-of-life care. PMID:26176303

  12. The Developmental Transition From Living With to Dying From Cancer: Hospice Decision Making.

    PubMed

    Waldrop, Deborah; Meeker, Mary Ann; Kutner, Jean S

    2015-01-01

    Despite increasing utilization of hospice care, older adults with cancer enroll in hospice for shorter periods of time than those with other life-limiting illnesses. How older adults with cancer and their family members consider hospice is unknown. The purpose of this study was to compare decision making in late-stage cancer in people who enrolled in hospice with those who declined. Concepts from the Carroll and Johnson (1990) decision-making framework guided the development of a hospice decision-making model. The study design was exploratory-descriptive, cross-sectional, and used a two-group comparison. Qualitative and quantitative data were collected in the same interview. Open-ended questions were used to explore the illness trajectory and decision-making process. The interrelationships between functional ability, quality of life, and social support with hospice decision making were assessed using the Katz, QLQ-30, and Lubben Social Network Scales. Study participants included 42 older adults with cancer who had been offered hospice enrollment (24 non-hospice and 18 hospice) and 38 caregivers (15 non-hospice and 23 hospice); N = 80. The decisional model illustrates that the recognition of advanced cancer and information and communication needs were experienced similarly by both groups. There was interaction between the decisional stages: formulation of awareness and generation of alternatives that informed the evaluation of hospice but these stages were different in the hospice and non-hospice groups. The hospice enrollment decision represents a critical developmental juncture, which is accompanied by a transformed identity and substantive cognitive shift. Increased attention to the psychosocial and emotional issues that accompany this transition are important for quality end-of-life care. PMID:26176303

  13. Carbon budgets and energy transition pathways

    NASA Astrophysics Data System (ADS)

    van Vuuren, Detlef P.; van Soest, Heleen; Riahi, Keywan; Clarke, Leon; Krey, Volker; Kriegler, Elmar; Rogelj, Joeri; Schaeffer, Michiel; Tavoni, Massimo

    2016-07-01

    Scenarios from integrated assessment models can provide insights into how carbon budgets relate to other policy-relevant indicators by including information on how fast and by how much emissions can be reduced. Such indicators include the peak year of global emissions, the decarbonisation rate and the deployment of low-carbon technology. Here, we show typical values for these indicators for different carbon budgets, using the recently compiled IPCC scenario database, and discuss how these vary as a function of non-CO2 forcing, energy use and policy delay. For carbon budgets of 2000 GtCO2 and less over the 2010–2100 period, supply of low carbon technologies needs to be scaled up massively from today’s levels, unless energy use is relatively low. For the subgroup of scenarios with a budget below 1000 GtCO2 (consistent with >66% chance of limiting global warming to below 2 °C relative to preindustrial levels), the 2050 contribution of low-carbon technologies is generally around 50%–75%, compared to less than 20% today (range refers to the 10–90th interval of available data).

  14. Carbon budgets and energy transition pathways

    NASA Astrophysics Data System (ADS)

    van Vuuren, Detlef P.; van Soest, Heleen; Riahi, Keywan; Clarke, Leon; Krey, Volker; Kriegler, Elmar; Rogelj, Joeri; Schaeffer, Michiel; Tavoni, Massimo

    2016-07-01

    Scenarios from integrated assessment models can provide insights into how carbon budgets relate to other policy-relevant indicators by including information on how fast and by how much emissions can be reduced. Such indicators include the peak year of global emissions, the decarbonisation rate and the deployment of low-carbon technology. Here, we show typical values for these indicators for different carbon budgets, using the recently compiled IPCC scenario database, and discuss how these vary as a function of non-CO2 forcing, energy use and policy delay. For carbon budgets of 2000 GtCO2 and less over the 2010-2100 period, supply of low carbon technologies needs to be scaled up massively from today’s levels, unless energy use is relatively low. For the subgroup of scenarios with a budget below 1000 GtCO2 (consistent with >66% chance of limiting global warming to below 2 °C relative to preindustrial levels), the 2050 contribution of low-carbon technologies is generally around 50%-75%, compared to less than 20% today (range refers to the 10-90th interval of available data).

  15. Thermomodulation spectra of high-energy interband transitions in Cu, Pd, Ag, Pt, and Au

    SciTech Connect

    Olson, C.G.; Lynch, D.W.; Rosei, R.

    1980-07-15

    Thermotransmission and thermoreflectance spectra were obtained for Cu, Pd, Ag, Pt, and Au in the 10 --30 eV spectral region. Structures due to transitions from the Fermi level to high-density bands 15 eV above the Fermi level were identified in Pt. All metals showed structures arising from interband transitions between the d bands and the same flat bands, 15--20 eV above the Fermi energy. Attempts to fit to interband critical points in Au revealed over 40 possible critical points in the region of these structures, most of them near the Brillouin-zone centers. Systematic trends in the series of metals make the qualitative identification of the structures more secure, and no energy shifts of calculated energy bands are required. The observed widths of structures are sometimes much narrower than the widths of free-electron-like bands at comparable energies.

  16. Industrial energy in transition: a petrochemical perspective.

    PubMed

    Wishart, R S

    1978-02-10

    The future growth of the petrochemical industry depends in part on the industry's ability to improve efficiency in the use of oil and gas feedstocks and to develop promising alternatives. Technological innovation is proving to be the key to the long-term viability of the industry. The next 6 to 7 years will be characterized by the commercialization of new technologies designed to improve the efficiency of petroleum as a feedstock. Union Carbide's advanced cracking reactor, now nearing the demonstration stage, exemplifies this type of effort. The increasing price of oil and gas will make coal-based synthesis gas more attractive as a feedstock, particularly for oxygenated petrochemical products. A further development involves the conversion of biomass, through fermentation, to useful chemical products and the gasification of municipal wastes to raise steam for electricity generation and as a possible, supplemental feedstock. By the year 2000, it is predicted that feedstocks from all sources other than oil and gas may constitute 10 to 14 percent of the total new material requirement for the petrochemical industry.

  17. Mothers' Transition Back to Work and Infants' Transition to Child Care: Does Work-Based Child Care Make a Difference?

    ERIC Educational Resources Information Center

    Skouteris, Helen; McCaught, Simone; Dissanayake, Cheryl

    2007-01-01

    The overall aim in this study was twofold: to compare the use of work-based (WB) and non-work-based (NWB) child care on the transition back to the workplace for women after a period of maternity leave, and on the transition into child care for the infants of these women. Thirty-five mothers with infants in WB centres and 44 mothers with infants in…

  18. Simple solvable energy-landscape model that shows a thermodynamic phase transition and a glass transition.

    PubMed

    Naumis, Gerardo G

    2012-06-01

    When a liquid melt is cooled, a glass or phase transition can be obtained depending on the cooling rate. Yet, this behavior has not been clearly captured in energy-landscape models. Here, a model is provided in which two key ingredients are considered in the landscape, metastable states and their multiplicity. Metastable states are considered as in two level system models. However, their multiplicity and topology allows a phase transition in the thermodynamic limit for slow cooling, while a transition to the glass is obtained for fast cooling. By solving the corresponding master equation, the minimal speed of cooling required to produce the glass is obtained as a function of the distribution of metastable states.

  19. Breaking and Making of Carbon-Carbon Bonds by Lanthanides and Third-Row Transition Metals.

    PubMed

    Zhou, Shaodong; Li, Jilai; Schlangen, Maria; Schwarz, Helmut

    2016-02-24

    Carbon-atom extrusion from the ipso-position of a halobenzene ring (C6 H5 X; X=F, Cl, Br, I) and its coupling with a methylene ligand to produce acetylene is not confined to [LaCH2 ](+) ; also, the third-row transition-metal complexes [MCH2 ](+) , M=Hf, Ta, W, Re, and Os, bring about this unusual transformation. However, substrates with substituents X=CN, NO2 , OCH3 , and CF3 are either not reactive at all or give rise to different products when reacted with [LaCH2 ](+) . In the thermal gas-phase processes of atomic Ln(+) with C7 H7 Cl substrates, only those lanthanides with a promotion energy small enough to attain a 4f(n) 5d(1) 6s(1) configuration are reactive and form both [LnCl](+) and [LnC5 H5 Cl](+) . Branching ratios and the reaction efficiencies of the various processes seem to correlate with molecular properties, like the bond-dissociation energies of the C-X or M(+) -X bonds or the promotion energies of lanthanides. PMID:26875940

  20. Smart Building: Decision Making Architecture for Thermal Energy Management.

    PubMed

    Uribe, Oscar Hernández; Martin, Juan Pablo San; Garcia-Alegre, María C; Santos, Matilde; Guinea, Domingo

    2015-10-30

    Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB) prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling) caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction.

  1. Smart Building: Decision Making Architecture for Thermal Energy Management

    PubMed Central

    Hernández Uribe, Oscar; San Martin, Juan Pablo; Garcia-Alegre, María C.; Santos, Matilde; Guinea, Domingo

    2015-01-01

    Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB) prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling) caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction. PMID:26528978

  2. Smart Building: Decision Making Architecture for Thermal Energy Management.

    PubMed

    Uribe, Oscar Hernández; Martin, Juan Pablo San; Garcia-Alegre, María C; Santos, Matilde; Guinea, Domingo

    2015-01-01

    Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB) prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling) caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction. PMID:26528978

  3. Transition Metal Nitrides for Electrocatalytic Energy Conversion: Opportunities and Challenges.

    PubMed

    Xie, Junfeng; Xie, Yi

    2016-03-01

    Electrocatalytic energy conversion has been considered as one of the most efficient and promising pathways for realizing energy storage and energy utilization in modern society. To improve electrocatalytic reactions, specific catalysts are needed to lower the overpotential. In the search for efficient alternatives to noble metal catalysts, transition metal nitrides have attracted considerable interest due to their high catalytic activity and unique electronic structure. Over the past few decades, numerous nitride-based catalysts have been explored with respect to their ability to drive various electrocatalytic reactions, such as the hydrogen evolution reaction and the oxygen evolution reaction to achieve water splitting and the oxygen reduction reaction coupled with the methanol oxidation reaction to construct fuel cells or rechargeable Li-O2 batteries. This Minireview provides a brief overview of recent progress on electrocatalysts based on transition metal nitrides, and outlines the current challenges and future opportunities. PMID:26494184

  4. The roles of users in shaping transitions to new energy systems

    NASA Astrophysics Data System (ADS)

    Schot, Johan; Kanger, Laur; Verbong, Geert

    2016-05-01

    Current government information policies and market-based instruments aimed at influencing the energy choices of consumers often ignore the fact that consumer behaviour is not fully reducible to individuals making rational conscious decisions all the time. The decisions of consumers are largely configured by shared routines embedded in socio-technical systems. To achieve a transition towards a decarbonized and energy-efficient system, an approach that goes beyond individual consumer choice and puts shared routines and system change at its centre is needed. Here, adopting a transitions perspective, we argue that consumers should be reconceptualized as users who are important stakeholders in the innovation process shaping new routines and enacting system change. We review the role of users in shifts to new decarbonized and energy-efficient systems and provide a typology of user roles.

  5. Energy Transition Initiative: Island Energy Snapshot - St. Lucia (Fact Sheet)

    SciTech Connect

    Not Available

    2015-02-01

    This profile provides a snapshot of the electricity generation or reduction technologies, including solar hot water heating, available to Saint Lucia, one of six Caribbean countries that make up the Windward Islands - the southern arc of the Lesser Antilles chain - at the eastern end of the Caribbean Sea. Heating and transportation fuels are not addressed.

  6. Energy Transition Initiative, Island Energy Snapshot - Grenada (Fact Sheet)

    SciTech Connect

    Not Available

    2015-03-01

    This profile provides a snapshot of the energy landscape of Grenada - a small island nation consisting of the island of Grenada and six smaller islands in the southeastern Caribbean Sea - three of which are inhabited: Grenada, Carriacou, and Petite Martinique.

  7. An earlier origin for stone tool making: implications for cognitive evolution and the transition to Homo.

    PubMed

    Lewis, Jason E; Harmand, Sonia

    2016-07-01

    The discovery of the earliest known stone tools at Lomekwi 3 (LOM3) from West Turkana, Kenya, dated to 3.3 Ma, raises new questions about the mode and tempo of key adaptations in the hominin lineage. The LOM3 tools date to before the earliest known fossils attributed to Homo at 2.8 Ma. They were made and deposited in a more C3 environment than were the earliest Oldowan tools at 2.6 Ma. Their discovery leads to renewed investigation on the timing of the emergence of human-like manipulative capabilities in early hominins and implications for reconstructing cognition. The LOM3 artefacts form part of an emerging paradigm shift in palaeoanthropology, in which: tool-use and tool-making behaviours are not limited to the genus Homo; cranial, post-cranial and behavioural diversity in early Homo is much wider than previously thought; and these evolutionary changes may not have been direct adaptations to living in savannah grassland environments.This article is part of the themed issue 'Major transitions in human evolution'. PMID:27298464

  8. Energy Efficienct Processes for Making Tackifier Dispersions used to make Pressure Sensitive Adhesives

    SciTech Connect

    Rakesh Gupta

    2006-07-26

    The primary objective of this project was to develop an energy efficient, environmentally friendly and low cost process (compared to the current process) for making tackifier dispersions that are used to make pressure-sensitive adhesives. These adhesives are employed in applications such as self-adhesive postage stamps and disposable diapers and are made by combining the tackifier dispersion with a natural or synthetic rubber latex. The current process for tackifier dispersion manufacture begins by melting a (plastic) resin and adding water to it in order to form a water-in-oil emulsion. This is then converted to an oil-in-water emulsion by phase inversion in the presence of continuous stirring. The resulting emulsion is the tackifier dispersion, but it is not concentrated and the remaining excess water has to be transported and removed. The main barrier that has to be overcome in the development of commercial quality tackifier dispersions is the inability to directly emulsify resin in water due to the very low viscosity of water as compared to the viscosity of the molten resin. In the present research, a number of solutions were proposed to overcome this barrier, and these included use of different mixer types to directly form the emulsion from the molten resin but without going through a phase inversion, the idea of forming a solid resin-in-water suspension having the correct size and size distribution but without melting of the resin, and the development of techniques of making a colloidal powder of the resin that could be dispersed in water just prior to use. Progress was made on each of these approaches, and each was found to be feasible. The most appealing solution, though, is the last one, since it does not require melting of the resin. Also, the powder can be shipped in dry form and then mixed with water in any proportion depending on the needs of the process. This research was conducted at Argonne National Laboratory, and it was determined the new process

  9. Biomolecular Dynamics: Order-Disorder Transitions and Energy Landscapes

    PubMed Central

    Whitford, Paul C.; Sanbonmatsu, Karissa Y.; Onuchic, José N.

    2013-01-01

    While the energy landscape theory of protein folding is now a widely accepted view for understanding how relatively-weak molecular interactions lead to rapid and cooperative protein folding, such a framework must be extended to describe the large-scale functional motions observed in molecular machines. In this review, we discuss 1) the development of the energy landscape theory of biomolecular folding, 2) recent advances towards establishing a consistent understanding of folding and function, and 3) emerging themes in the functional motions of enzymes, biomolecular motors, and other biomolecular machines. Recent theoretical, computational, and experimental lines of investigation are providing a very dynamic picture of biomolecular motion. In contrast to earlier ideas, where molecular machines were thought to function similarly to macroscopic machines, with rigid components that move along a few degrees of freedom in a deterministic fashion, biomolecular complexes are only marginally stable. Since the stabilizing contribution of each atomic interaction is on the order of the thermal fluctuations in solution, the rigid body description of molecular function must be revisited. An emerging theme is that functional motions encompass order-disorder transitions and structural flexibility provide significant contributions to the free-energy. In this review, we describe the biological importance of order-disorder transitions and discuss the statistical-mechanical foundation of theoretical approaches that can characterize such transitions. PMID:22790780

  10. Phase/Shape Transitions and the Two Neutron Separation Energies

    SciTech Connect

    Zamfir, N. V.; Anghel, Sabina; Cata-Danil, G.

    2008-11-11

    We investigated the evolution of experimental two-neutron separation energies (S{sub 2n}) along the isotopic chains for the even-even nuclei. In order to enhance the sensitivity of our search, differential variation of the S{sub 2n} has been investigated. The emphasis is on finding nonmonotonic behaviors which can be correlated with phase/shape transition. Correlations of the ground state S{sub 2n} values with the excited states energies R{sub 4/2} ratio are also discussed.

  11. Transitions into the negative-energy Dirac continuum

    SciTech Connect

    Krekora, P.; Su, Q.; Grobe, R.

    2004-11-01

    We compare the predictions of the single-particle Dirac equation with quantum field theory for an electron subjected to a space and time dependent field. We demonstrate analytically and numerically that a transition into the negative-energy subspace predicted by the single-particle Dirac equation is directly associated with the degree of suppression of pair-production as described by quantum field theory. We show that the portion of the mathematical wave function that populates the negative-energy states corresponds to the difference between the positron spatial density for systems with and without an electron initially present.

  12. Energy and population: transitional issues and eventual limits.

    PubMed

    Werbos, P J

    1990-08-01

    The implication of population size for US energy requirements is explored in this essay. The basic argument is that the present supply of fuels and energy technologies is not sustainable in the long run, that a wide range of choices is possible when a complete transition is made to sustainable technologies, and that the growth of population and the composition of this growth during the next 30 years are the most serious problems impacting on the achievement of sustainable technology. The importance and future of fuel oil is discussed as well as the transition to sustainable energy supplies: conservation, renewables, nuclear and coal. Dependency on oil can only be changed through time and the infusion of money, but even with these givens, the transition is also dependent on the political and budgetary climate. The race is between crisis and cure. It is argued that the soft energy systems (biomass, solar water heater, wind, hydro, and geothermal energy) along with conservation will increase easily and naturally, but the total potential from these sources amounts to only 10% of the present US energy supply. Conservation offers greater hope because 80% of end-use fossil fuel is used in transportation and industry. Further growth of the population in the US would create a demand to desalinate water, which would increase the demand for energy. A totally soft energy economy is probably not feasible without a drastic reduction in US population. The expected direction is in the increased use of coal, and then nuclear energy. Unfortunately, coal contributes to greenhouse warming, and the supply is limited to 60-100 years. Nuclear proliferation and terrorism is connected to the widespread use of nuclear energy. Some breakthrough technology with cold fusion may offer a safer alternative. High technology renewables such as solar cells can be competitive with nuclear energy, if prices can be kept down. on earth or in space, are being investigated. Exploring a variety of advanced

  13. Energy and population: transitional issues and eventual limits.

    PubMed

    Werbos, P J

    1990-08-01

    The implication of population size for US energy requirements is explored in this essay. The basic argument is that the present supply of fuels and energy technologies is not sustainable in the long run, that a wide range of choices is possible when a complete transition is made to sustainable technologies, and that the growth of population and the composition of this growth during the next 30 years are the most serious problems impacting on the achievement of sustainable technology. The importance and future of fuel oil is discussed as well as the transition to sustainable energy supplies: conservation, renewables, nuclear and coal. Dependency on oil can only be changed through time and the infusion of money, but even with these givens, the transition is also dependent on the political and budgetary climate. The race is between crisis and cure. It is argued that the soft energy systems (biomass, solar water heater, wind, hydro, and geothermal energy) along with conservation will increase easily and naturally, but the total potential from these sources amounts to only 10% of the present US energy supply. Conservation offers greater hope because 80% of end-use fossil fuel is used in transportation and industry. Further growth of the population in the US would create a demand to desalinate water, which would increase the demand for energy. A totally soft energy economy is probably not feasible without a drastic reduction in US population. The expected direction is in the increased use of coal, and then nuclear energy. Unfortunately, coal contributes to greenhouse warming, and the supply is limited to 60-100 years. Nuclear proliferation and terrorism is connected to the widespread use of nuclear energy. Some breakthrough technology with cold fusion may offer a safer alternative. High technology renewables such as solar cells can be competitive with nuclear energy, if prices can be kept down. on earth or in space, are being investigated. Exploring a variety of advanced

  14. Solar Electricity and Solar Fuels: Status and Perspectives in the Context of the Energy Transition.

    PubMed

    Armaroli, Nicola; Balzani, Vincenzo

    2016-01-01

    The energy transition from fossil fuels to renewables is already ongoing, but it will be a long and difficult process because the energy system is a gigantic and complex machine. Key renewable energy production data show the remarkable growth of solar electricity technologies and indicate that crystalline silicon photovoltaics (PV) and wind turbines are the workhorses of the first wave of renewable energy deployment on the TW scale around the globe. The other PV alternatives (e.g., copper/indium/gallium/selenide (CIGS) or CdTe), along with other less mature options, are critically analyzed. As far as fuels are concerned, the situation is significantly more complex because making chemicals with sunshine is far more complicated than generating electric current. The prime solar artificial fuel is molecular hydrogen, which is characterized by an excellent combination of chemical and physical properties. The routes to make it from solar energy (photoelectrochemical cells (PEC), dye-sensitized photoelectrochemical cells (DSPEC), PV electrolyzers) and then synthetic liquid fuels are presented, with discussion on economic aspects. The interconversion between electricity and hydrogen, two energy carriers directly produced by sunlight, will be a key tool to distribute renewable energies with the highest flexibility. The discussion takes into account two concepts that are often overlooked: the energy return on investment (EROI) and the limited availability of natural resources-particularly minerals-which are needed to manufacture energy converters and storage devices on a multi-TW scale. PMID:26584653

  15. Solar Electricity and Solar Fuels: Status and Perspectives in the Context of the Energy Transition.

    PubMed

    Armaroli, Nicola; Balzani, Vincenzo

    2016-01-01

    The energy transition from fossil fuels to renewables is already ongoing, but it will be a long and difficult process because the energy system is a gigantic and complex machine. Key renewable energy production data show the remarkable growth of solar electricity technologies and indicate that crystalline silicon photovoltaics (PV) and wind turbines are the workhorses of the first wave of renewable energy deployment on the TW scale around the globe. The other PV alternatives (e.g., copper/indium/gallium/selenide (CIGS) or CdTe), along with other less mature options, are critically analyzed. As far as fuels are concerned, the situation is significantly more complex because making chemicals with sunshine is far more complicated than generating electric current. The prime solar artificial fuel is molecular hydrogen, which is characterized by an excellent combination of chemical and physical properties. The routes to make it from solar energy (photoelectrochemical cells (PEC), dye-sensitized photoelectrochemical cells (DSPEC), PV electrolyzers) and then synthetic liquid fuels are presented, with discussion on economic aspects. The interconversion between electricity and hydrogen, two energy carriers directly produced by sunlight, will be a key tool to distribute renewable energies with the highest flexibility. The discussion takes into account two concepts that are often overlooked: the energy return on investment (EROI) and the limited availability of natural resources-particularly minerals-which are needed to manufacture energy converters and storage devices on a multi-TW scale.

  16. Vertical transition energies vs. absorption maxima: illustration with the UV absorption spectrum of ethylene.

    PubMed

    Lasorne, Benjamin; Jornet-Somoza, Joaquim; Meyer, Hans-Dieter; Lauvergnat, David; Robb, Michael A; Gatti, Fabien

    2014-02-01

    We revisit the validity of making a direct comparison between measured absorption maxima and computed vertical transition energies within 0.1 eV to calibrate an excited-state level of theory. This is illustrated on the UV absorption spectrum of ethylene for which the usual experimental values of 7.66 eV (V←N) and 7.11 eV (R(3s)←N) cannot be compared directly to the results of electronic structure calculations for two very different reasons. After validation of our level of theory against experimental data, a new experimental reference of 7.28 eV is suggested for benchmarking the Rydberg state, and the often-cited average transition energy (7.80 eV) is confirmed as a safer estimate for the valence state.

  17. Public Discourse in Energy Policy Decision-Making: Final Report

    SciTech Connect

    Idaho Citizen; Eileen DeShazo; John Freemuth; Tina Giannini; Troy Hall; Ann Hunter; Jeffrey C. Joe; Michael Louis; Carole Nemnich; Jennie Newman; Steven J. Piet; Stephen Sorensen; Paulina Starkey; Kendelle Vogt; Patrick Wilson

    2010-08-01

    The ground is littered with projects that failed because of strong public opposition, including natural gas and coal power plants proposed in Idaho over the past several years. This joint project , of the Idaho National Laboratory, Boise State University, Idaho State University and University of Idaho has aimed to add to the tool box to reduce project risk through encouraging the public to engage in more critical thought and be more actively involved in public or social issues. Early in a project, project managers and decision-makers can talk with no one, pro and con stakeholder groups, or members of the public. Experience has shown that talking with no one outside of the project incurs high risk because opposition stakeholders have many means to stop most (if not all) energy projects. Talking with organized stakeholder groups provides some risk reduction from mutual learning, but organized groups tend not to change positions except under conditions of a negotiated settlement. Achieving a negotiated settlement may be impossible. Furthermore, opposition often arises outside pre-existing groups. Standard public polling provides some information but does not reveal underlying motivations, intensity of attitudes, etc. Improved methods are needed that probe deeper into stakeholder (organized groups and members of the public) values and beliefs/heuristics to increase the potential for change of opinions and/or out-of-box solutions. The term “heuristics” refers to the mental short-cuts, underlying beliefs, and paradigms that everyone uses to filter and interpret information, to interpret what is around us, and to guide our actions and decisions. This document is the final report of a 3-year effort to test different public discourse methods in the subject area of energy policy decision-making. We analyzed 504 mail-in surveys and 80 participants in groups on the Boise State University campus for their preference, financial support, and evaluations of eight attributes

  18. A Framework for Supporting Organizational Transition Processes Towards Sustainable Energy Systems

    NASA Astrophysics Data System (ADS)

    Buch, Rajesh

    Economic development over the last century has driven a tripling of the world's population, a twenty-fold increase in fossil fuel consumption, and a tripling of traditional biomass consumption. The associated broad income and wealth inequities are retaining over 2 billion people in poverty. Adding to this, fossil fuel combustion is impacting the environment across spatial and temporal scales and the cost of energy is outpacing all other variable costs for most industries. With 60% of world energy delivered in 2008 consumed by the commercial and industrial sector, the fragmented and disparate energy-related decision making within organizations are largely responsible for the inefficient and impacting use of energy resources. The global transition towards sustainable development will require the collective efforts of national, regional, and local governments, institutions, the private sector, and a well-informed public. The leadership role in this transition could be provided by private and public sector organizations, by way of sustainability-oriented organizations, cultures, and infrastructure. The diversity in literature exemplifies the developing nature of sustainability science, with most sustainability assessment approaches and frameworks lacking transformational characteristics, tending to focus on analytical methods. In general, some shortfalls in sustainability assessment processes include lack of: · thorough stakeholder participation in systems and stakeholder mapping, · participatory envisioning of future sustainable states, · normative aggregation of results to provide an overall measure of sustainability, and · influence within strategic decision-making processes. Specific to energy sustainability assessments, while some authors aggregate results to provide overall sustainability scores, assessments have focused solely on energy supply scenarios, while including the deficits discussed above. This paper presents a framework for supporting

  19. A phase transition in energy-filtered RNA secondary structures.

    PubMed

    Han, Hillary S W; Reidys, Christian M

    2012-10-01

    In this article we study the effect of energy parameters on minimum free energy (mfe) RNA secondary structures. Employing a simplified combinatorial energy model that is only dependent on the diagram representation and is not sequence-specific, we prove the following dichotomy result. Mfe structures derived via the Turner energy parameters contain only finitely many complex irreducible substructures, and just minor parameter changes produce a class of mfe structures that contain a large number of small irreducibles. We localize the exact point at which the distribution of irreducibles experiences this phase transition from a discrete limit to a central limit distribution and, subsequently, put our result into the context of quantifying the effect of sparsification of the folding of these respective mfe structures. We show that the sparsification of realistic mfe structures leads to a constant time and space reduction, and that the sparsification of the folding of structures with modified parameters leads to a linear time and space reduction. We, furthermore, identify the limit distribution at the phase transition as a Rayleigh distribution.

  20. Nanostructured transition metal oxides for energy storage and conversion

    NASA Astrophysics Data System (ADS)

    Li, Qiang

    Lithium-ion batteries, supercapacitors and photovoltaic devices have been widely considered as the three major promising alternatives of fossil fuels facing upcoming depletion to power the 21th century. The conventional film configuration of electrochemical electrodes hardly fulfills the high energy and efficiency requirements because heavy electroactive material deposition restricts ion diffusion path, and lowers power density and fault tolerance. In this thesis, I demonstrate that novel nanoarchitectured transition metal oxides (TMOs), e.g. MnO2, V2O 5, and ZnO, and their relevant nanocomposites were designed, fabricated and assembled into devices to deliver superior electrochemical performances such as high energy and power densities, and rate capacity. These improvements could be attributed to the significant enhancement of surface area, shortened ion diffusion distances and facile penetration of electrolyte solution into open structures of networks as well as to the pseudocapacitance domination. The utilization of ForcespinningRTM, a newly developed nanofiber processing technology, for large-scale energy storage and conversion applications is emphasized. This process simplifies the tedious multi-step hybridization synthesis and facilitates the contradiction between the micro-batch production and the ease of large-scale manufacturing. Key Words: Transition metal oxides, energy storage and conversion, ForcespinningRTM, pseudocapacitance domination, high rate capacity

  1. Many-body energy localization transition in periodically driven systems

    SciTech Connect

    D’Alessio, Luca; Polkovnikov, Anatoli

    2013-06-15

    According to the second law of thermodynamics the total entropy of a system is increased during almost any dynamical process. The positivity of the specific heat implies that the entropy increase is associated with heating. This is generally true both at the single particle level, like in the Fermi acceleration mechanism of charged particles reflected by magnetic mirrors, and for complex systems in everyday devices. Notable exceptions are known in noninteracting systems of particles moving in periodic potentials. Here the phenomenon of dynamical localization can prevent heating beyond certain threshold. The dynamical localization is known to occur both at classical (Fermi–Ulam model) and at quantum levels (kicked rotor). However, it was believed that driven ergodic systems will always heat without bound. Here, on the contrary, we report strong evidence of dynamical localization transition in both classical and quantum periodically driven ergodic systems in the thermodynamic limit. This phenomenon is reminiscent of many-body localization in energy space. -- Highlights: •A dynamical localization transition in periodically driven ergodic systems is found. •This phenomenon is reminiscent of many-body localization in energy space. •Our results are valid for classical and quantum systems in the thermodynamic limit. •At critical frequency, the short time expansion for the evolution operator breaks down. •The transition is associated to a divergent time scale.

  2. Summer Center for Climate, Energy, and Environmental Decision Making (SUCCEED)

    NASA Astrophysics Data System (ADS)

    Klima, K.; Hoss, F.; Welle, P.; Larkin, S.

    2013-12-01

    Science, Technology, and Math (STEM) fields are responsible for more than half of our sustained economic expansion, and over the past 25 years the science and engineering workforce has remained at over 5% of all U.S. jobs. However, America lags behind other nations when it comes to STEM education; globally, American students rank 23th in math and 31st in science. While our youngest students show an interest in STEM subjects, roughly 40% of college students planning to major in STEM switch to other subjects. Women and minorities, 50% and 43% of school-age children, are disproportionally underrepresented in STEM fields (25% and 15%, respectively). Studies show that improved teacher curriculum combined with annual student-centered learning summer programs can promote and sustain student interest in STEM fields. Many STEM fields appear superficially simple, and yet can be truly complex and controversial topics. Carnegie Mellon University's Center for Climate and Energy Decision Making focuses on two such STEM fields: climate and energy. In 2011, we created SUCCEED: the Summer Center for Climate, Energy, and Environmental Decision Making. SUCCEED consisted of two pilot programs: a 2-day workshop for K-12 teacher professional development and a free 5-day summer school targeted at an age gap in the university's outreach, students entering 10th grade. In addition to teaching lessons climate, energy, and environment, the program aimed to highlight different STEM careers so students could better understand the breadth of choices available. SUCCEED, repeated in 2012, was wildly successful. A pre/post test demonstrated a significant increase in understanding of STEM topics. Furthermore, SUCCEED raised excitement for STEM; teachers were enthusiastic about accurate student-centered learning plans and students wanted to know more. To grow these efforts, an additional component has been added to the SUCCEED 2013 effort: online publicly available curricula. Using the curricula form

  3. Making a Drama out of Transition: Challenges and Opportunities at Times of Change

    ERIC Educational Resources Information Center

    Hammond, Nick

    2016-01-01

    This case study explored how teachers and children perceive challenges and opportunities at transition. Using Forum Theatre (FT), an interactive drama approach, children were able to show aspects of transitions they perceived as challenging and how these barriers may be overcome. FT offered a tangible reference point for children to discuss their…

  4. "Ready for Big School": Making the Transition to Primary School--A Jamaican Perspective

    ERIC Educational Resources Information Center

    Kinkead-Clark, Zoyah

    2015-01-01

    The aim of this small-scale, qualitative study is to understand the perspective of varying stakeholders responsible for student transitions from pre-primary to primary school in the Jamaican context. The questions that guided the research are: What factors affect student transitions to primary school? What skills do children need in order to…

  5. Making It on Civvy Street: An Online Survey of Canadian Veterans in Transition

    ERIC Educational Resources Information Center

    Black, Timothy; Papile, Chiara

    2010-01-01

    The authors present the results of a non-governmental study focusing on Canadian Forces veterans and their experiences of transition from the military into civilian society. The study was based on a survey that gathered basic demographic data and veterans' subjective experiences of their transition out of the Canadian military into civilian life.…

  6. Moving from Middle to High School: Making Sense of the Freshman Transition

    ERIC Educational Resources Information Center

    Dudley, Rachel E.

    2012-01-01

    Educators have noticed students moving from eighth grade middle school programs to ninth grade high school environments encounter difficulties during the first year of the transition. Students who do not successfully transition to high school run the risk of repeating ninth grade, falling behind their peers and possibly dropping out of high…

  7. From Initial Education to Working Life: Making Transitions Work. Education and Skills.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France).

    The Organisation for Economic Cooperation and Development (OECD) conducted a thematic review to identify changes in young people's transition to working life during the 1990s and to identify those policies and programs that are effective in delivering successful transition outcomes for young people. The review focused on 14 countries with widely…

  8. Energy levels and radiative rates for transitions in Ga XXIV

    SciTech Connect

    El-Sayed, Fatma

    2012-07-15

    Energy levels, transition probabilities, oscillator strengths, line strengths, and lifetimes have been calculated for Oxygen-like Gallium, Ga XXIV. The configurations 2s{sup 2}2p{sup 4}, 2s2p{sup 5}, 2p{sup 6}, 2s2p{sup 4}3 Script-Small-L , 2s{sup 2}2p{sup 3}3 Script-Small-L , and 2p{sup 5}3 Script-Small-L were used in calculations and 226 fine-structure levels were obtained. The fully relativistic GRASP code has been adopted, and results are reported for all electric dipole (E1), electric quadrupole (E2), magnetic dipole (M1), and magnetic quadrupole (M2) transitions among the lowest 226 levels of Ga XXIV, belonging to the n{<=}3 configurations. Comparisons have been made with earlier available theoretical and experimental results.

  9. Kinetic energy budget of Typhoon Yagi (2006) during its extratropical transition

    NASA Astrophysics Data System (ADS)

    Sun, Yuan; Zhong, Zhong; Wang, Yuan

    2012-10-01

    A diagnostic energetic analysis is conducted to study the kinetic energy budget during the extratropical transition (ET) of tropical cyclone (TC) Yagi (2006), using high-resolution numerical model output. The results show that the upper-level jet stream makes great contribution to the redevelopment of Yagi. When the Yagi approached to the upper-level jet stream, the horizontal flux of kinetic energy associated with the jet was the major cause of the ET. During the transition of Yagi, the horizontal flux of kinetic energy caused by the change of environmental field related to the TC movement only accounted for about 25 % of the total flux, while the horizontal convergence to Yagi under the action of the jet was the major portion of the total horizontal flux. Moreover, the work of pressure gradient force changed from a source of kinetic energy to a sink in the upper troposphere before and after the ET, however, it acted as a source of kinetic energy in the lower and middle troposphere all the time, and both the vertical and horizontal fluxes of kinetic energy caused by the upper-level jet increased the kinetic energy in the upper troposphere. The sub-grid scale friction and dissipation, which shows their maximum effects in the lower troposphere especially in the atmospheric boundary layer, played major consumption roles against the pressure gradient force. Furthermore, the consumption was almost entirely out-of-phase for the convective transport of kinetic energy in vertical, and inhibited the vertical flux of kinetic energy. In addition, there were significant high-frequency disturbances before and after the ET characterized by out-of-phase kinetic energy changes between upper and lower levels, thus, the vertically integrated kinetic energy budget in the air column could not give a reasonable physical image for TC kinetic energy variation.

  10. Thermal energy storage device and method for making the same

    SciTech Connect

    Campbell, S.

    1981-11-10

    A thermal energy storage device and method for making the same are described. The thermal energy storage device is in the form of a sealed tube-like container such as a tube-like cylinder or other geometrical configuration partially filled with a phase change material such as calcium chloride hexahydrate. The cylinder is made of tubular high density polyethylene and more particularly an ultra high molecular weight high density polyethylene having a molecular weight of about 500,000 to 700,000 which is tough, chemically resistant, withstands low and high temperatures, acts as a moisture vapor barrier and can be fused and sealed. The calcium hexahydrate is filled in an open top cylinder, closed at the bottom by dissolving two parts of calcium chloride dihydrate with one part of water to provide calcium chloride hexahydrate in liquid form. The cylinder is filled to about 90% by volume and a cap of the same material is then preheated to about fusion temperature. The open top of the cylinder is then brought up to fusion temperature and the cap is fused to it under pressure.

  11. Making the transition to middle schooling: A case study of experienced science teachers coping with change

    NASA Astrophysics Data System (ADS)

    Strong, Donna Dorough

    The increasing popularity of the middle school movement necessitates a need for more interpretive research in middle level education. The purpose of this qualitative case study was to explore science teachers' perceptions of the transition to a new middle school and the meanings they attached to this new experience. The participants were three eighth grade science teachers, each with 20 plus years of teaching experience. The primary data for analysis was a series of five interviews with each participant. Data collection also included weekly participant observation of team meetings. Findings revealed that the science teachers all had positive feelings attached to the ability to keep track of students' academic progress and behavior problems as a result of teaming. The changes associated with the first year were very stressful for all three, primarily the loss of the traditional junior high departmentalized structure. The two participants who transferred directly from the junior high school were very skeptical of any benefits from an interdisciplinary curriculum, the appropriateness of the middle school philosophy for eighth grade students, and the move to heterogeneously grouped science classes. In contrast, the former junior high teacher who had spent the past ten years teaching sixth grade at the elementary school had positive beliefs about the potential benefits of an interdisciplinary curriculum and heterogeneous grouping. Teacher stress associated with a change in the school setting and the science teachers' constraints to actualizing a meaningful middle schooling experience are illuminated. Teachers' lack of ownership in the reform decision making process, loss of time with their science teacher peers, diminished compliments from high school counterparts, and need for more empirical evidence supporting proposed changes all served as barriers to embracing the reform initiatives. The participants found taking a very slow approach to be their most useful means of

  12. Acceleressence: Dark energy from a phase transition at the seesawscale

    SciTech Connect

    Chacko, Z.; Hall, Lawrence J.; Nomura, Yasunori

    2004-10-05

    Simple models are constructed for ''acceleressence'' dark energy: the latent heat of a phase transition occurring in a hidden sector governed by the seesaw mass scale v{sup 2}/M{sub Pl}, where v is the electroweak scale and M{sub Pl} the gravitational mass scale. In our models, the seesaw scale is stabilized by supersymmetry, implying that the LHC must discover superpartners with a spectrum that reflects a low scale of fundamental supersymmetry breaking. Newtonian gravity may be modified by effects arising from the exchange of fields in the acceleressence sector whose Compton wavelengths are typically of order the millimeter scale. There are two classes of models. In the first class the universe is presently in a metastable vacuum and will continue to inflate until tunneling processes eventually induce a first order transition. In the simplest such model, the range of the new force is bounded to be larger than 25 {micro}m in the absence of fine-tuning of parameters, and for couplings of order unity it is expected to be {approx} 100 {micro}m. In the second class of models thermal effects maintain the present vacuum energy of the universe, but on further cooling, the universe will ''soon'' smoothly relax to a matter dominated era. In this case, the range of the new force is also expected to be of order the millimeter scale or larger, although its strength is uncertain. A firm prediction of this class of models is the existence of additional energy density in radiation at the eV era, which can potentially be probed in precision measurements of the cosmic microwave background. An interesting possibility is that the transition towards a matter dominated era has occurred in the very recent past, with the consequence that the universe is currently decelerating.

  13. Transitivity vs. intransitivity in decision making process - an example in quantum game theory

    NASA Astrophysics Data System (ADS)

    Makowski, Marcin

    2009-06-01

    We compare two different ways of quantum modification in a simple sequential game called Cat's Dilemma in the context of the debate on intransitive and transitive preferences. This kind of analysis can have essential meaning for research on artificial intelligence (some possibilities are discussed). Nature has both transitive and intransitive properties and perhaps quantum models will be more able to capture this dualism than the classical models. We also present an electoral interpretation of the game.

  14. Global Warming and Energy Transition: A Public Policy Imperative

    NASA Astrophysics Data System (ADS)

    Stone, G. T.

    2006-12-01

    The historic transition from fossil fuels to alternative energy resources has begun. This development is commonly attributed to increasing energy costs and the need for energy security. Looming ever larger, however, is the issue that will soon drive the third energy revolution: global warming. A preponderance of evidence documents accelerating warming, enlarging impacts, and human causes -- principally combustion of fossil fuels. The carbon dioxide (C02) content of Earth's atmosphere has increased more than 35 percent since the beginning of the industrial revolution and is the highest in 650,000 years. This dramatic rise of C02 and attendant positive feedbacks are already forcing significant impacts worldwide. These include atmospheric warming with shifting climatic and habitat zones, spreading tropical disease, and more extreme weather events; rapid ice loss at high latitude and high altitude; ocean warming and acidification with coral reef bleaching and intensifying tropical storms; rising sea level; and accelerating extinction rates. The 2007 draft report of the Intergovernmental Panel on Climate Change (IPCC) predicts greater warming than in previous models. A tipping point to abrupt climate change may be imminent. It is incumbent upon geoscientists and geoscience educators to assume leadership in addressing this challenge through public outreach and general education. The following topics should be integrated into all appropriate courses: the evidence of global warming and its causes; observed present and predicted future impacts of global warming; mitigation and adaptation strategies; and implications for energy policies and economic opportunities. New entry-level science and general education courses -- such as Climate Change Fundamentals and Energy in Nature, Technology, and Society -- are proving to be effective should be widely developed In addition, by workshops and presentations to civic and business organizations and by demonstrated examples of

  15. Steering quantum transitions between three crossing energy levels

    SciTech Connect

    Ivanov, S. S.; Vitanov, N. V.

    2008-02-15

    We calculate the propagator and the transition probabilities for a coherently driven three-state quantum system. The energies of the three states change linearly in time, whereas the interactions between them are pulse shaped. We derive a highly accurate analytic approximation by assuming independent pairwise Landau-Zener transitions occurring instantly at the relevant avoided crossings, and adiabatic evolution elsewhere. Quantum interferences are identified, which occur due to different possible evolution paths in Hilbert space between an initial and a final state. A detailed comparison with numerical results for Gaussian-shaped pulses demonstrates a remarkable accuracy of the analytic approximation. We use the analytic results to derive estimates for the half-width of the excitation profile, and for the parameters required for creation of a maximally coherent superposition of the three states. These results are of potential interest in ladder climbing in alkali-metal atoms by chirped laser pulses, in quantum rotors, in transitions between Zeeman sublevels of a J=1 level in a magnetic field, and in control of entanglement of a pair of spin-1/2 particles. The results for the three-state system can be generalized, without essential difficulties, to higher dimensions.

  16. Transition Metal Carbides and Nitrides in Energy Storage and Conversion

    PubMed Central

    Zhong, Yu; Shi, Fan; Zhan, Jiye; Tu, Jiangping

    2016-01-01

    High‐performance electrode materials are the key to advances in the areas of energy conversion and storage (e.g., fuel cells and batteries). In this Review, recent progress in the synthesis and electrochemical application of transition metal carbides (TMCs) and nitrides (TMNs) for energy storage and conversion is summarized. Their electrochemical properties in Li‐ion and Na‐ion batteries as well as in supercapacitors, and electrocatalytic reactions (oxygen evolution and reduction reactions, and hydrogen evolution reaction) are discussed in association with their crystal structure/morphology/composition. Advantages and benefits of nanostructuring (e.g., 2D MXenes) are highlighted. Prospects of future research trends in rational design of high‐performance TMCs and TMNs electrodes are provided at the end. PMID:27812464

  17. [Energy cost of running during a specific transition in duathlon].

    PubMed

    Vallier, Jean-Marc; Mazure, Cyrille; Hausswirth, Christophe; Bernard, Thierry; Brisswalter, Jeanick

    2003-10-01

    The aim of the present study was to investigate the variability of the energy cost of running (Cr) during a simulated duathlon performed in outdoor conditions by elite duathletes. This duathlon consisted of 5 km of running, 30 km of cycling, and 5 km of running. The main result was the lack of significant difference in Cr between the two running bouts (210 +/- 10 mL d'O2.km-1.kg-1 vs. 217 +/- 10 mL d'O2.km-1.kg-1). This result is different from those observed during a triathlon, where an increase of energy cost of running bout has been reported. Furthermore, during a short-distance duathlon performed by well-trained subjects, none of the physiological (ventilation alteration, metabolic changes, or dehydration) or biomechanical factors that are classically evoked in triathlon research to explain Cr variability seem to be affected by the run-cycle-run transition. These results seem to minimize the negative effect of the cycle-to-run transition during a short-duration event in well-trained subjects. PMID:14710519

  18. City-Level Energy Decision Making. Data Use in Energy Planning, Implementation, and Evaluation in U.S. Cities

    SciTech Connect

    Aznar, Alexandra; Day, Megan; Doris, Elizabeth; Mathur, Shivani; Donohoo-Vallett, Paul

    2015-07-08

    The Cities-LEAP technical report, City-Level Energy Decision Making: Data Use in Energy Planning, Implementation, and Evaluation in U.S. Cities, explores how a sample of cities incorporates data into making energy-related decisions. This report provides the foundation for forthcoming components of the Cities-LEAP project that will help cities improve energy decision making by mapping specific city energy or climate policies and actions to measurable impacts and results.

  19. Toward the renewables - A natural gas/solar energy transition strategy

    NASA Technical Reports Server (NTRS)

    Hanson, J. A.; Escher, W. J. D.

    1979-01-01

    The inevitability of an energy transition from today's non-renewable fossil base toward a renewable energy base is considered from the viewpoint of the need for a national transition strategy. Then, one such strategy is offered. Its technological building blocks are described in terms of both energy use and energy supply. The strategy itself is then sketched at four points in its implementation; (1) initiation, (2) early transition, (3) late transition, and (4) completion. The transition is assumed to evolve from a heavily natural gas-dependent energy economy. It then proceeds through its transition toward a balanced, hybrid energy system consisting of both centralized and dispersed energy supply technologies supplying hydrogen and electricity from solar energy. Related institutional, environmental and economic factors are examined briefly.

  20. Nudged-elastic band method with two climbing images: Finding transition states in complex energy landscapes

    DOE PAGES

    Zarkevich, Nikolai A.; Johnson, Duane D.

    2015-01-09

    The nudged-elastic band (NEB) method is modified with concomitant two climbing images (C2-NEB) to find a transition state (TS) in complex energy landscapes, such as those with a serpentine minimal energy path (MEP). If a single climbing image (C1-NEB) successfully finds the TS, then C2-NEB finds it too. Improved stability of C2-NEB makes it suitable for more complex cases, where C1-NEB misses the TS because the MEP and NEB directions near the saddle point are different. Generally, C2-NEB not only finds the TS, but guarantees, by construction, that the climbing images approach it from the opposite sides along the MEP.more » In addition, C2-NEB provides an accuracy estimate from the three images: the highest-energy one and its climbing neighbors. C2-NEB is suitable for fixed-cell NEB and the generalized solid-state NEB.« less

  1. Nudged-elastic band method with two climbing images: Finding transition states in complex energy landscapes

    SciTech Connect

    Zarkevich, Nikolai A.; Johnson, Duane D.

    2015-01-09

    The nudged-elastic band (NEB) method is modified with concomitant two climbing images (C2-NEB) to find a transition state (TS) in complex energy landscapes, such as those with a serpentine minimal energy path (MEP). If a single climbing image (C1-NEB) successfully finds the TS, then C2-NEB finds it too. Improved stability of C2-NEB makes it suitable for more complex cases, where C1-NEB misses the TS because the MEP and NEB directions near the saddle point are different. Generally, C2-NEB not only finds the TS, but guarantees, by construction, that the climbing images approach it from the opposite sides along the MEP. In addition, C2-NEB provides an accuracy estimate from the three images: the highest-energy one and its climbing neighbors. C2-NEB is suitable for fixed-cell NEB and the generalized solid-state NEB.

  2. Practice Makes Perfect? University Students' Response to a First-Year Transition Course

    ERIC Educational Resources Information Center

    Browning, Catherine; Sheffield, Suzanne Le-May

    2008-01-01

    This paper shares new insights on the first-year university student transition experience. Our research focuses on students' practice of academic skills developed in a "Foundations for Learning" course, from their own perspective, after they completed the course. Once they had an opportunity to practice what they learned in subsequent…

  3. Making Community Connections: Educator Perspectives on Transition Planning for Students with Intellectual Disabilities

    ERIC Educational Resources Information Center

    Schwartz, Karen; Mactavish, Jennifer; Lutfiyya, Zana Marie

    2006-01-01

    For students with intellectual disabilities and their families, planning for the transition from school to adult life can be a complicated process. Successful planning is sometimes made more challenging when post-school options and opportunities are not well known or understood. The purpose of this study is to seek out the perspectives of…

  4. Rocking & Rolling: Supporting Infants, Toddlers, and Their Families. Helping Babies Make Transitions

    ERIC Educational Resources Information Center

    Merrill, Sarah; Britt, Donna

    2008-01-01

    The authors discuss three steps to helping babies with transitions: observe, ask, and respond (OAR). They advise teachers about how to ask a family questions about their baby and how to give the family suggestions to alleviate the baby's stress, without offending family members. This column includes a list of recommended resources. (Contains 7…

  5. Making the Transition: An Explanatory Model of Special Education Students' Participation in Postsecondary Education.

    ERIC Educational Resources Information Center

    Butler-Nalin, Paul; And Others

    The report of the National Longitudinal Transition Study presents initial findings on individual characteristics which relate to postsecondary education participation since 1985-86 among more than 8,000 youth (ages 13 to 23) with disabilities. A series of logistic regression models examines such factors as youth's background characteristics,…

  6. Anxiety Levels in Students with Autism Spectrum Disorder Making the Transition from Primary to Secondary School

    ERIC Educational Resources Information Center

    Hannah, Elizabeth F.; Topping, Keith J.

    2012-01-01

    The anxiety levels of students with autism spectrum disorder (ASD) over the period of transition from primary to secondary school are investigated. A repeated measures design and an adapted version of a self-report measure, the Spence Children's Anxiety Scale (SCAS), are used to compare the anxiety levels of eight students before and after the…

  7. The Work Experiences of Transgender Individuals: Negotiating the Transition and Career Decision-Making Processes

    ERIC Educational Resources Information Center

    Budge, Stephanie L.; Tebbe, Esther N.; Howard, Kimberly A. S.

    2010-01-01

    This study explored the work experiences of individuals who have started transitioning from their biological sex to a different gender expression through 18 interviews of transgender-identified individuals. Thirteen of the participants identified as male-to-female transsexuals, 2 participants identified as female-to-male transsexuals, 2…

  8. Transitioning Persons with Moderate and Severe Disabilities from School to Adulthood: What Makes It Work?

    ERIC Educational Resources Information Center

    Wheeler, Jill

    This book is intended to assist anyone who is interested in the quality of life afforded persons with moderate and severe disabilities, including educators, residential providers, vocational rehabilitation personnel, social staff, parents, and advocates. The first section, which deals with the reasons why transition is needed, covers the following…

  9. Hydrogen and Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the Federal Transit Administration (Report and Appendix)

    SciTech Connect

    Eudy, L.; Chandler, K.

    2008-05-01

    This document describes the hydrogen transit bus evaluations performed by the National Renewable Energy Laboratory (NREL) and funded by the U.S. Department of Energy (DOE) and the U.S. Department of Transportation's Federal Transit Administration (FTA).

  10. How We Make Energy Work: Grades 4, 5, 6 Science.

    ERIC Educational Resources Information Center

    National Science Teachers Association, Washington, DC.

    This packet of units is designed to focus on the technological aspects of energy. Four units are presented, with from 1-4 lessons included in each unit. Units include: (1) basic concepts and applications of energy; (2) steps and processes of energy production and transmission; (3) fuel acquisition; and (4) energy futures and application of…

  11. Energy Transition Initiative, Island Energy Snapshot - British Virgin Islands (Fact Sheet)

    SciTech Connect

    Not Available

    2015-03-01

    This profile provides a snapshot of the energy landscape of the British Virgin Islands (BVI), one of three sets of the Virgin Island territories in an archipelago making up the northern portion of the Lesser Antilles.

  12. Interactions between negative energy balance, metabolic diseases, uterine health and immune response in transition dairy cows.

    PubMed

    Esposito, Giulia; Irons, Pete C; Webb, Edward C; Chapwanya, Aspinas

    2014-01-30

    The biological cycles of milk production and reproduction determine dairying profitability thus making management decisions dynamic and time-dependent. Diseases also negatively impact on net earnings of a dairy enterprise. Transition cows in particular face the challenge of negative energy balance (NEB) and/or disproportional energy metabolism (fatty liver, ketosis, subacute, acute ruminal acidosis); disturbed mineral utilization (milk fever, sub-clinical hypocalcemia); and perturbed immune function (retained placenta, metritis, mastitis). Consequently NEB and reduced dry matter intake are aggravated. The combined effects of all these challenges are reduced fertility and milk production resulting in diminishing profits. Risk factors such as NEB, inflammation and impairment of the immune response are highly cause-and-effect related. Thus, managing cows during the transition period should be geared toward reducing NEB or feeding specially formulated diets to improve immunity. Given that all cows experience a reduced feed intake and body condition, infection and inflammation of the uterus after calving, there is a need for further research on the immunology of transition dairy cows. Integrative approaches at the molecular, cellular and animal level may unravel the complex interactions between disturbed metabolism and immune function that predispose cows to periparturient diseases.

  13. Process for making whiskers, fibers and flakes of transition metal compounds

    DOEpatents

    Bamberger, Carlos E.

    1992-01-01

    A process for making titanium and chromium nitrides of known morphology by reacting potassium titanate and chromium oxide in the gas phase with NH.sub.3. The products exhibit the same morphology as the starting material.

  14. Process for making whiskers, fibers and flakes of transition metal compounds

    DOEpatents

    Bamberger, C.E.

    1992-06-02

    A process for making titanium and chromium nitrides of known morphology by reacting potassium titanate and chromium oxide in the gas phase with NH[sub 3]. The products exhibit the same morphology as the starting material.

  15. Transition Metal Oxide Alloys as Potential Solar Energy Conversion Materials

    SciTech Connect

    Toroker, Maytal; Carter, Emily A.

    2013-02-21

    First-row transition metal oxides (TMOs) are inexpensive potentia alternative materials for solar energy conversion devices. However, some TMOs, such as manganese(II) oxide, have band gaps that are too large for efficiently absorbing solar energy. Other TMOs, such as iron(II) oxide, have conduction and valence band edges with the same orbital character that may lead to unfavorably high electron–hole recombination rates. Another limitation of iron(II) oxide is that the calculated valence band edge is not positioned well for oxidizing water. We predict that key properties, including band gaps, band edge positions, and possibly electron–hole recombination rates, may be improved by alloying TMOs that have different band alignments. A new metric, the band gap center offset, is introduced for simple screening of potential parent materials. The concept is illustrated by calculating the electronic structure of binary oxide alloys that contain manganese, nickel, iron, zinc, and/or magnesium, within density functional theory (DFT)+U and hybrid DFT theories. We conclude that alloys of iron(II) oxide are worth evaluating further as solar energy conversion materials.

  16. Making the transition to the third era of natural resources management

    USGS Publications Warehouse

    Stephenson, Nathan L.

    2015-01-01

    We are entering the third era of National Park Service (NPS) natural resources management— an era defined by rapid and unprecedented global changes. This third era promises to overturn not only some of our most fundamental assumptions about parks and protected areas, but also many of the ideals we currently hold dear. A common initial reaction to the diverse challenges of this transition is to feel overwhelmed and adrift; I have certainly had such feelings myself. But these feelings carry the risk of reducing our effectiveness as resource stewards right when we can least afford to be less effective: during a transition that is demanding us to be particularly clear-headed and far-seeing. Here I briefly examine some of the challenges of this new era, focusing on those that can most often elicit feelings of discouragement. When we examine the challenges individually, they begin to lose some of their ability to cast gloom—especially when we consider them in the light of lessons from an earlier fundamental transition in NPS natural resources management, beginning a half-century ago. My perspective is shaped by my 35 years as a place-based scientist stationed in a large national park (Sequoia and Kings Canyon), and by my passion for national parks in general. While the discussion that follows is most relevant to large national parks set aside primarily for their natural features, several of the ideas are also relevant to other park units.

  17. Household Energy Consumption: Community Context and the Fuelwood Transition*

    PubMed Central

    Link, Cynthia F.; Axinn, William G.; Ghimire, Dirgha J.

    2012-01-01

    We examine the influence of community context on change over time in households’ use of non-wood fuels. Our theoretical framework builds on sociological concepts in order to study energy consumption at the micro-level. The framework emphasizes the importance of nonfamily organizations and services in the local community as determinants of the transition from use of fuelwood to use of alternative fuels. We use multilevel longitudinal data on household fuel choice and community context from rural Nepal to provide empirical tests of our theoretical model. Results reveal that increased exposure to nonfamily organizations in the local community increases the use of alternative fuels. The findings illustrate key features of human impacts on the local environment and motivate greater incorporation of social organization into research on environmental change. PMID:23017795

  18. Noise-induced transitions in rugged energy landscapes

    NASA Astrophysics Data System (ADS)

    Duncan, A. B.; Kalliadasis, S.; Pavliotis, G. A.; Pradas, M.

    2016-09-01

    We consider the problem of an overdamped Brownian particle moving in multiscale potential with N +1 characteristic length scales: the macroscale and N separated microscales. We show that the coarse-grained dynamics is given by an overdamped Langevin equation with respect to the free energy and with a space-dependent diffusion tensor, the calculation of which requires the solution of N fully coupled Poisson equations. We study in detail the structure of the bifurcation diagram for one-dimensional problems, and we show that the multiscale structure in the potential leads to hysteresis effects and to noise-induced transitions. Furthermore, we obtain an explicit formula for the effective diffusion coefficient for a self-similar separable potential, and we investigate the limit of infinitely many small scales.

  19. Transition metal oxide hierarchical nanotubes for energy applications.

    PubMed

    Wei, Wei; Wang, Yongcheng; Wu, Hao; Al-Enizi, Abdullah M; Zhang, Lijuan; Zheng, Gengfeng

    2016-01-15

    We report a general synthetic method for transition metal oxide (TMO) hierarchical nanotube (HNT) structures by a solution-phase cation exchange method from Cu2O nanowire templates. This method leads to the formation of hollow, tubular backbones with secondary, thin nanostructures on the tube surface, which substantially increases the surface reactive sites for electrolyte contacts and electrochemical reactions. As proofs-of-concept, several representative first-row TMO HNTs have been synthesized, including CoOx, NiOx, MnOx, ZnOx and FeOx, with specific surface areas much larger than nanotubes or nanoparticles of corresponding materials. An example of the potential energy storage applications of CoOx HNTs as supercapacitors is also demonstrated. PMID:26629880

  20. A Model for Education: Energy-Water Consumption Decision Making.

    ERIC Educational Resources Information Center

    Bontrager, Ralph L.; Hubbard, Charles W.

    Public schools are in a position to convince society-at-large of the national energy problem. There is a direct relationship between energy costs to the schools and the type of educational programs they can provide. While waiting for a national energy policy with a section devoted to schools, districts can calculate the amount and cost of energy…

  1. A Guide to making Energy-Smart Purchases

    SciTech Connect

    1999-04-01

    Being more energy efficient can be as simple and inexpensive as buying and installing caulk and weatherstripping or as complicated and expensive as building a state-of-the-art, energy-efficient house. However, whatever you do to reduce energy costs will usually require the purchase of goods or services.

  2. With a Little Help from Their Friends: Making the Transition from Student to Teacher

    ERIC Educational Resources Information Center

    Spangler, Susan

    2013-01-01

    A university's seminar model suggests the design of a collaborative structure that promotes team sharing and problem solving. The mentoring that occurs in the seminar comes mainly from the student teachers sharing their experiences with each other and working together to make sense of their classrooms in the context of the theories they have…

  3. Who Makes It to Secondary School? Determinants of Transition to Secondary Schools in Rural India

    ERIC Educational Resources Information Center

    Siddhu, Gaurav

    2011-01-01

    Despite considerable progress made, a significant proportion of children continue to drop out before reaching secondary school in India. This study investigates factors influencing parental decision-making with regard to children's secondary schooling in the context of a rural area of Uttar Pradesh. The study finds that cost, distance to the…

  4. Methods for finding transition states on reduced potential energy surfaces

    NASA Astrophysics Data System (ADS)

    Burger, Steven K.; Ayers, Paul W.

    2010-06-01

    Three new algorithms are presented for determining transition state (TS) structures on the reduced potential energy surface, that is, for problems in which a few important degrees of freedom can be isolated. All three methods use constrained optimization to rapidly find the TS without an initial Hessian evaluation. The algorithms highlight how efficiently the TS can be located on a reduced surface, where the rest of the degrees of freedom are minimized. The first method uses a nonpositive definite quasi-Newton update for the reduced degrees of freedom. The second uses Shepard interpolation to fit the Hessian and starts from a set of points that bound the TS. The third directly uses a finite difference scheme to calculate the reduced degrees of freedom of the Hessian of the entire system, and searches for the TS on the full potential energy surface. All three methods are tested on an epoxide hydrolase cluster, and the ring formations of cyclohexane and cyclobutenone. The results indicate that all the methods are able to converge quite rapidly to the correct TS, but that the finite difference approach is the most efficient.

  5. Energy boost in laser wakefield accelerators using sharp density transitions

    NASA Astrophysics Data System (ADS)

    Döpp, A.; Guillaume, E.; Thaury, C.; Lifschitz, A.; Ta Phuoc, K.; Malka, V.

    2016-05-01

    The energy gain in laser wakefield accelerators is limited by dephasing between the driving laser pulse and the highly relativistic electrons in its wake. Since this phase depends on both the driver and the cavity length, the effects of dephasing can be mitigated with appropriate tailoring of the plasma density along propagation. Preceding studies have discussed the prospects of continuous phase-locking in the linear wakefield regime. However, most experiments are performed in the highly non-linear regime and rely on self-guiding of the laser pulse. Due to the complexity of the driver evolution in this regime, it is much more difficult to achieve phase locking. As an alternative, we study the scenario of rapid rephasing in sharp density transitions, as was recently demonstrated experimentally. Starting from a phenomenological model, we deduce expressions for the electron energy gain in such density profiles. The results are in accordance with particle-in-cell simulations, and we present gain estimations for single and multiple stages of rephasing.

  6. Nanotechnology makes biomass electrolysis more energy efficient than water electrolysis

    NASA Astrophysics Data System (ADS)

    Chen, Y. X.; Lavacchi, A.; Miller, H. A.; Bevilacqua, M.; Filippi, J.; Innocenti, M.; Marchionni, A.; Oberhauser, W.; Wang, L.; Vizza, F.

    2014-06-01

    The energetic convenience of electrolytic water splitting is limited by thermodynamics. Consequently, significant levels of hydrogen production can only be obtained with an electrical energy consumption exceeding 45 kWh kg-1H2. Electrochemical reforming allows the overcoming of such thermodynamic limitations by replacing oxygen evolution with the oxidation of biomass-derived alcohols. Here we show that the use of an original anode material consisting of palladium nanoparticles deposited on to a three-dimensional architecture of titania nanotubes allows electrical energy savings up to 26.5 kWh kg-1H2 as compared with proton electrolyte membrane water electrolysis. A net energy analysis shows that for bio-ethanol with energy return of the invested energy larger than 5.1 (for example, cellulose), the electrochemical reforming energy balance is advantageous over proton electrolyte membrane water electrolysis.

  7. Rail transit energy management program. Final report for 1993-94 calendar year effort. Volume 1

    SciTech Connect

    Uher, R.A.

    1995-03-01

    To meet the challenge of continuously rising energy costs for rail transit in North America, the Rail Systems Center (RSC) at Carnegie Mellon University has established the Rail Transit Energy Management Program. This program is a private-public partnership of rail transit authorities, the electric utilities which supply them energy and suppliers to both the transit and the electric utility industry. The long range goal of the program is to reduce rail transit energy costs by 10% or $46 million, annually. The program is built upon an already successful effort of energy cost reduction among several rail transit authorities and the RSC. This report describes the effort expended on the program during the calendar years 1993-94.

  8. Rail transit energy management program. Final report, calendar year 1995-1996. Final report

    SciTech Connect

    Uher, R.A.

    1996-04-01

    To meet the challenge of continuously rising energy costs for rail transit in North America, the Rail Systems Center (RSC) at Carnegie Mellon University has established the Rail transit Energy management Program. This program is a private-public partnership of rail transit authorities, the electric utilities which supply them energy and suppliers to both the transit and the electric utility industry. The long range goal of the program is to reduce rail transit energy costs by 10% or $46 million, annually. The program is built upon an already successful effort of energy cost reduction among several rail transit authorities and the RSC. The report describes the effort expended on the program during the clanedar years 1995-1996.

  9. Energy at the Frontier: Low Carbon Energy System Transitions and Innovation in Four Prime Mover Countries

    NASA Astrophysics Data System (ADS)

    Araujo, Kathleen M.

    All too often, discussion about the imperative to change national energy pathways revolves around long timescales and least cost economics of near-term energy alternatives. While both elements certainly matter, they don't fully reflect what can drive such development trajectories. This study explores national energy transitions by examining ways in which four prime mover countries of low carbon energy technology shifted away from fossil fuels, following the first global oil crisis of 1973. The research analyzes the role of readiness, sectoral contributions and adaptive policy in the scale-up and innovations of advanced, alternative energy technologies. Cases of Brazilian biofuels, Danish wind power, French nuclear power and Icelandic geothermal energy are analyzed for a period of four decades. Fundamentally, the research finds that significant change can occur in under 15 years; that technology complexity need not necessarily impede change; and that countries of different governance approaches and consumption levels can effectuate such transitions. This research also underscores that low carbon energy technologies may be adopted before they are competitive and then become competitive in the process. (Copies available exclusively from MIT Libraries, libraries.mit.edu/docs - docs mit.edu)

  10. Sustainable Schools: Making Energy Efficiency a Lifestyle Priority

    ERIC Educational Resources Information Center

    Purnell, Ken; Sinclair, Mark; Gralton, Anna

    2004-01-01

    Promoting efficient energy use in schools that consequently reduces greenhouse gas emissions is the purpose of a residential Energy Efficiency in Schools (EEIS) program reported on in this paper. Research on this program aligns with one of the "key "overarching" sustainability issues", set out in the "Learning for Sustainability: NSW Environmental…

  11. Making sense of the transition from the Detroit streets to drug treatment.

    PubMed

    Draus, Paul; Roddy, Juliette; Asabigi, Kanzoni

    2015-02-01

    In this article we consider the process of adjustment from active street sex work to life in structured substance abuse treatment among Detroit-area women who participated in a semicoercive program administered through a drug court. We examine this transition in terms of changes in daily routines and social networks, drawing on extensive qualitative data to illuminate the ways in which women defined their own situations. Using concepts from Bourdieu and Latour as analytical aids, we analyze the role of daily routines, environments, and networks in producing the shifts in identity that those who embraced the goals of recovery demonstrated. We conclude with a discussion of how the restrictive environments and redundant situations experienced by women in treatment could be paradoxically embraced as a means to achieve expanded opportunity and enhanced individual responsibility because women effectively reassembled their social networks and identities to align with the goals of recovery.

  12. Making sense of the transition from the Detroit streets to drug treatment.

    PubMed

    Draus, Paul; Roddy, Juliette; Asabigi, Kanzoni

    2015-02-01

    In this article we consider the process of adjustment from active street sex work to life in structured substance abuse treatment among Detroit-area women who participated in a semicoercive program administered through a drug court. We examine this transition in terms of changes in daily routines and social networks, drawing on extensive qualitative data to illuminate the ways in which women defined their own situations. Using concepts from Bourdieu and Latour as analytical aids, we analyze the role of daily routines, environments, and networks in producing the shifts in identity that those who embraced the goals of recovery demonstrated. We conclude with a discussion of how the restrictive environments and redundant situations experienced by women in treatment could be paradoxically embraced as a means to achieve expanded opportunity and enhanced individual responsibility because women effectively reassembled their social networks and identities to align with the goals of recovery. PMID:25246332

  13. Risk management in facility transition and management decision making: Needs and opportunities

    SciTech Connect

    Stillwell, W.; Seaver, D.; Keller, J. ); Smith, D. ); Weaver, D.; Sanders, T. ); Thullen, P. )

    1993-02-01

    An overall approach to risk management is described in this paper. Many of these concepts have been developed and applied as part of Hanford Mission Planning (HMP) (Hanford Mission Plan, 1992). At Hanford, HMP provides a mechanism for integrating planning across all the missions and programs of the site. This paper discusses the decision context within which EM must make and defend decisions, the types of decisions that are being and will need to be made in order to progress with the cleanup of the DOE complex, and the resulting need for risk management. Risk management, in turn, requires quality health and ecological risk information to make these decisions. Other types of information are also needed, but the risk information is typically the most important and the most difficult to obtain. The paper then describes a general technical approach to risk management, including particular methods for developing the high quality of human health and ecological risk information that will be needed to support risk management. We next turn to several special issues that make risk management more complex than many other decisions. We discuss these issues and offer some practical suggestions with respect to addressing them in the risk management framework. Finally, we conclude with some discussion of other opportunities for applying risk management.

  14. Transits

    NASA Astrophysics Data System (ADS)

    Gilliland, Ronald L.

    Transits of the planets Mercury and especially Venus have been exciting events in the development of astronomy over the past few hundred years. Just two years ago the first transiting extra-solar planet, HD 209458b, was discovered, and subsequent studies during transit have contributed fundamental new knowledge. From the photometric light curve during transit one obtains a basic confirmation that the radial velocity detected object is indeed a planet by allowing precise determination of its mass and radius relative to these stellar quantities. From study of spectroscopic changes during transit it has been possible to probe for individual components of the transiting planets atmosphere. Planet transits are likely to become a primary tool for detection of new planets, especially other Earth-like planets with the Kepler Discovery Mission. Looking ahead, the additional aperture of the James Webb Space Space Telescope promises to allow the first possibility of studying the atmosphere of extra-solar Earth-analogue planets, perhaps even providing the first evidence of direct relevance to the search for signs of life on other planets.

  15. Development and application of a battery energy storage system simulation program for rail transit systems. Volume 3. Final report

    SciTech Connect

    Ball, C.E.; Uher, R.A.

    1995-03-01

    Under the Rail Transit Energy Management Program, a computer model was developed to assess the economic feasibility of applying battery energy storage to rail transit systems. This model was applied to the Port Authority of Allegheny County (PAT) (Pittsburgh) light rail system and the Washington Metropolitan Area Transit Authority`s (WMATA) MetroRail. The results indicate that the payback periods for investment into battery energy storage and relatively long; 14 years for WMATA and 10 years for PAT. These payback periods are marginal and with the risk associated with implementing battery storage, it is doubtful whether transit management would be inclined to make such an investment. The capital cost of battery storage can be reduced by eliminating the power conditioning equipment and allowing the battery to be connected directly to the third rail catenary or trolley system. The model can easily be modified to assess the economic feasibility of other alternative energy sources such as cogeneration and other storage media, such as superconducting magnetic energy storage.

  16. Controlling Light to Make the Most Energy From the Sun

    SciTech Connect

    Callahan, Dennis; Corcoran, Chris; Eisler, Carissa; Flowers, Cris; Goodman, Matt; Hofmann, Carrie; Sadtler, Bryce

    2013-07-18

    Representing the Light-Material Interactions in Energy Conversion (LMI), this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE energy. The mission of LMI to tailor the morphology, complex dielectric structure, and electronic properties of matter so as to sculpt the flow of sunlight and heat, enabling light conversion to electrical and chemical energy with unprecedented efficiency.

  17. Can decoherence make quantum theories unfalsifiable? Understanding the quantum-to-classical transition without it

    NASA Astrophysics Data System (ADS)

    Oriols, X.

    2016-03-01

    Exact predictions for most quantum systems are computationally inaccessible. This is the so-called many body problem, which is present in most common interpretations of quantum mechanics. Therefore, predictions of natural quantum phenomena have to rely on some approximations (assumptions or simplifications). In the literature, there are different types of approximations, ranging from those whose justification is basically based on theoretical developments to those whose justification lies on the agreement with experiments. This last type of approximations can convert a quantum theory into an “unfalsifiable” quantum theory, true by construction. On the practical side, converting some part of a quantum theory into an “unfalsifiable” one ensures a successful modeling (i.e. compatible with experiments) for quantum engineering applications. An example of including irreversibility and dissipation in the Bohmian modeling of open systems is presented. On the ontological level, however, the present-day foundational problems related to controversial quantum phenomena have to avoid (if possible) being contaminated by the unfalsifiability originated from the many body problem. An original attempt to show how the Bohmian theory itself (minimizing the role of many body approximations) explains the transitions from a microscopic quantum system towards a macroscopic classical one is presented.

  18. Using Constant Time Delay to Teach Braille and the Nemeth Code for Mathematics and Science Notation to Students Making the Transition from Print to Braille

    ERIC Educational Resources Information Center

    Ivy, Sarah E.; Hooper, Jonathan D.

    2015-01-01

    Introduction: Many students with adventitious vision loss or progressive vision loss need to transition from print to braille as a primary literacy medium. It is important that this transition is handled efficiently so that the student can have continued access to a literacy medium and make progress in the core curriculum. For this study, we used…

  19. Computerization of clinical laboratories and health care facilities: Making decisions in transition. Part I: General considerations.

    PubMed

    Thomas, S

    1994-01-01

    In summary, it is perhaps appropriate to reflect on the transition zone that health care finds itself in now. Federally and provincially funded Royal Commission reports and health surveys over the last thirty years have all drawn a number of similar conclusions. Some of these are particularly important to keep in mind as major investments in hospital and laboratory information systems are made. First, it is known that health care providers and services are not distributed evenly throughout the country and that there is uneven utilization of services. Second, the "health" in health care is not defined in purely medical terms. Health is a function of genetic background, personal choices and behaviors like diet and exercise, socioeconomic conditions like housing, family situations, education, and employment, and the physical environment in which an individual lives and works. Governments at all levels now use this concept of health when determining policy and funding. Third, a change of emphasis has occurred from the traditional hospital-centered model to one that is community based. How well will your laboratory and facility responding to the inevitable changes to funding and consumer utilization? How well does the HIS/LIS vendor understand the circumstances affecting your organization and what agreements can be made to ensure future system support? How will an increase in profile-type testing and reflexive testing be handled to minimize disruptions to work flow and productivity? How can analytical instrument selection change the whole focus of the laboratory operation and impact on other areas? Will the traditional terms "in patient" and "out patient" still apply, or will a term somewhere in the middle evolve?(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Specific Barriers and Drivers in Different Stages of Decision-Making about Energy Efficiency Upgrades in Private Homes

    PubMed Central

    Klöckner, Christian A.; Nayum, Alim

    2016-01-01

    Energy efficiency upgrades of privately owned homes like adding to the insulation layers in the walls, roof or floor, or replacing windows with more efficiently insulated versions can contribute significantly to reducing the energy impact of the building sector and thus also the CO2 footprint of a household. However, even in countries like Norway that have a rather high rate of renovation, energy upgrades are not always integrated into such a refurbishment project. This study tests which structural and internal psychological barriers hinder and which drivers foster decision-making to implement such measures, once a renovation project is planned. With a theoretical background in stage-based models of decision-making 24 barriers and drivers were tested for their specific effect in the stages of decision-making. The four stages of decision-making assumed in this study were (1) “not being in a decision mode,” (2) “deciding what to do,” (3) “deciding how to do it,” and (4) “planning implementation.” Based on an online survey of 3787 Norwegian households, it was found that the most important barriers toward deciding to implement energy efficiency upgrades were not owning the dwelling and feeling the right time had not come yet. The most important drivers of starting to decide were higher expected comfort levels, better expected living conditions, and an expected reduction of energy costs. For the transition from deciding what to do to how to do it, not managing to make a decision and feeling the right point in time has not come yet were the strongest barriers, easily accessible information and an expected reduction of energy costs were the most important drivers. The final transition from deciding how to do the upgrades to planning implementation was driven by expecting a payoff within a reasonable time frame and higher expected comfort levels; the most important barriers were time demands for supervising contractors and—again—a feeling that the right

  1. Specific Barriers and Drivers in Different Stages of Decision-Making about Energy Efficiency Upgrades in Private Homes.

    PubMed

    Klöckner, Christian A; Nayum, Alim

    2016-01-01

    Energy efficiency upgrades of privately owned homes like adding to the insulation layers in the walls, roof or floor, or replacing windows with more efficiently insulated versions can contribute significantly to reducing the energy impact of the building sector and thus also the CO2 footprint of a household. However, even in countries like Norway that have a rather high rate of renovation, energy upgrades are not always integrated into such a refurbishment project. This study tests which structural and internal psychological barriers hinder and which drivers foster decision-making to implement such measures, once a renovation project is planned. With a theoretical background in stage-based models of decision-making 24 barriers and drivers were tested for their specific effect in the stages of decision-making. The four stages of decision-making assumed in this study were (1) "not being in a decision mode," (2) "deciding what to do," (3) "deciding how to do it," and (4) "planning implementation." Based on an online survey of 3787 Norwegian households, it was found that the most important barriers toward deciding to implement energy efficiency upgrades were not owning the dwelling and feeling the right time had not come yet. The most important drivers of starting to decide were higher expected comfort levels, better expected living conditions, and an expected reduction of energy costs. For the transition from deciding what to do to how to do it, not managing to make a decision and feeling the right point in time has not come yet were the strongest barriers, easily accessible information and an expected reduction of energy costs were the most important drivers. The final transition from deciding how to do the upgrades to planning implementation was driven by expecting a payoff within a reasonable time frame and higher expected comfort levels; the most important barriers were time demands for supervising contractors and-again-a feeling that the right point in time has

  2. Specific Barriers and Drivers in Different Stages of Decision-Making about Energy Efficiency Upgrades in Private Homes

    PubMed Central

    Klöckner, Christian A.; Nayum, Alim

    2016-01-01

    Energy efficiency upgrades of privately owned homes like adding to the insulation layers in the walls, roof or floor, or replacing windows with more efficiently insulated versions can contribute significantly to reducing the energy impact of the building sector and thus also the CO2 footprint of a household. However, even in countries like Norway that have a rather high rate of renovation, energy upgrades are not always integrated into such a refurbishment project. This study tests which structural and internal psychological barriers hinder and which drivers foster decision-making to implement such measures, once a renovation project is planned. With a theoretical background in stage-based models of decision-making 24 barriers and drivers were tested for their specific effect in the stages of decision-making. The four stages of decision-making assumed in this study were (1) “not being in a decision mode,” (2) “deciding what to do,” (3) “deciding how to do it,” and (4) “planning implementation.” Based on an online survey of 3787 Norwegian households, it was found that the most important barriers toward deciding to implement energy efficiency upgrades were not owning the dwelling and feeling the right time had not come yet. The most important drivers of starting to decide were higher expected comfort levels, better expected living conditions, and an expected reduction of energy costs. For the transition from deciding what to do to how to do it, not managing to make a decision and feeling the right point in time has not come yet were the strongest barriers, easily accessible information and an expected reduction of energy costs were the most important drivers. The final transition from deciding how to do the upgrades to planning implementation was driven by expecting a payoff within a reasonable time frame and higher expected comfort levels; the most important barriers were time demands for supervising contractors and—again—a feeling that the right

  3. Specific Barriers and Drivers in Different Stages of Decision-Making about Energy Efficiency Upgrades in Private Homes.

    PubMed

    Klöckner, Christian A; Nayum, Alim

    2016-01-01

    Energy efficiency upgrades of privately owned homes like adding to the insulation layers in the walls, roof or floor, or replacing windows with more efficiently insulated versions can contribute significantly to reducing the energy impact of the building sector and thus also the CO2 footprint of a household. However, even in countries like Norway that have a rather high rate of renovation, energy upgrades are not always integrated into such a refurbishment project. This study tests which structural and internal psychological barriers hinder and which drivers foster decision-making to implement such measures, once a renovation project is planned. With a theoretical background in stage-based models of decision-making 24 barriers and drivers were tested for their specific effect in the stages of decision-making. The four stages of decision-making assumed in this study were (1) "not being in a decision mode," (2) "deciding what to do," (3) "deciding how to do it," and (4) "planning implementation." Based on an online survey of 3787 Norwegian households, it was found that the most important barriers toward deciding to implement energy efficiency upgrades were not owning the dwelling and feeling the right time had not come yet. The most important drivers of starting to decide were higher expected comfort levels, better expected living conditions, and an expected reduction of energy costs. For the transition from deciding what to do to how to do it, not managing to make a decision and feeling the right point in time has not come yet were the strongest barriers, easily accessible information and an expected reduction of energy costs were the most important drivers. The final transition from deciding how to do the upgrades to planning implementation was driven by expecting a payoff within a reasonable time frame and higher expected comfort levels; the most important barriers were time demands for supervising contractors and-again-a feeling that the right point in time has

  4. Spin symmetry transitions make DNA strands separate. New insight into the mechanism of transcription

    NASA Astrophysics Data System (ADS)

    Tulub, Alexander A.; Stefanov, Vassily E.

    2015-12-01

    The DFT:B3LYP (6-31G** basis set) method, including the hyperfine and spin-orbit couplings (HFC and SOC, respectively), is used to study the separation of two complementary trinucleotide sequences, (dC-dG-dA)-(dG-dC-dT), upon the action of two Mg(2+) cofactors (a simplified model). The computations reveal a crossing of the singlet (S) potential energy surface by the triplet (T) surface at two distinct points. Within the crossing region the T curve lies below the S curve. Adhering to the concept of the minimal energy path, one can assume that the T path is more favorable compared to that of the S path. The T path is not simple; it consists of two, T+ and T-, curves initially separated by the HFC and SOC. On reaching the second crossing point, both curves merge into the T0 state, which facilitates the T → S transfer. Totally, the process of the two trinucleotide separation (the first step of transcription) appears as the S → T → S symmetry conversion.

  5. Spin symmetry transitions make DNA strands separate. New insight into the mechanism of transcription.

    PubMed

    Tulub, Alexander A; Stefanov, Vassily E

    2015-01-01

    The DFT:B3LYP (6-31G** basis set) method, including the hyperfine and spin-orbit couplings (HFC and SOC, respectively), is used to study the separation of two complementary trinucleotide sequences, (dC-dG-dA)-(dG-dC-dT), upon the action of two Mg(2+) cofactors (a simplified model). The computations reveal a crossing of the singlet (S) potential energy surface by the triplet (T) surface at two distinct points. Within the crossing region the T curve lies below the S curve. Adhering to the concept of the minimal energy path, one can assume that the T path is more favorable compared to that of the S path. The T path is not simple; it consists of two, T+ and T-, curves initially separated by the HFC and SOC. On reaching the second crossing point, both curves merge into the T0 state, which facilitates the T → S transfer. Totally, the process of the two trinucleotide separation (the first step of transcription) appears as the S → T → S symmetry conversion. PMID:26656910

  6. Viscosity, glass transition and activation energy of solid cis-polyisoprene and trans-polyisoprene blends

    NASA Astrophysics Data System (ADS)

    Baboo, Mahesh; Sharma, Kananbala; Saxena, N. S.

    2011-11-01

    Blends of cis-polyisoprene (CPI) and trans-polyisoprene (TPI) have been prepared by solution casting to study viscosity, glass transition temperature and activation energy for the glass transition. The viscosity of blends having different weight ratios has been obtained through a single experiment measuring storage and loss modulus using the dynamic mechanical analyser technique. The glass transition temperature is determined through the temperature at which the minimum of temperature derivative curve of viscosity falls. The activation energy of glass transition and fragility index have been obtained by employing the Vogel-Fulchar-Tammann (VFT) equation by assuming non-Arrhenius behaviour of viscosity of polymer blends. Results indicate that both glass transition and activation energy for the glass transition are influenced by composition and crosslink density of the blend.

  7. Coal exports may make Australia's energy sector among least sustainable

    SciTech Connect

    2009-11-15

    Plentiful coal and cheap energy prices have resulted in an unusually heavy carbon footprint. Clearly, Australia has to rethink how much coal it will use to feed its own growing economy while becoming more conscious of its significant carbon export problem. For a country long used to digging the coal out of the ground and shipping it overseas, climate change will be a game changer.

  8. Critical behavior in the inverse to forward energy transition in two-dimensional magnetohydrodynamic flow.

    PubMed

    Seshasayanan, Kannabiran; Alexakis, Alexandros

    2016-01-01

    We investigate the critical transition from an inverse cascade of energy to a forward energy cascade in a two-dimensional magnetohydrodynamic flow as the ratio of magnetic to mechanical forcing amplitude is varied. It is found that the critical transition is the result of two competing processes. The first process is due to hydrodynamic interactions and cascades the energy to the large scales. The second process couples small-scale magnetic fields to large-scale flows, transferring the energy back to the small scales via a nonlocal mechanism. At marginality the two cascades are both present and cancel each other. The phase space diagram of the transition is sketched.

  9. Hanford Site cleanup and transition: Risk data needs for decision making (Hanford risk data gap analysis decision guide)

    SciTech Connect

    Gajewski, S.; Glantz, C.; Harper, B.; Bilyard, G.; Miller, P.

    1995-10-01

    Given the broad array of environmental problems, technical alternatives, and outcomes desired by different stakeholders at Hanford, DOE will have to make difficult resource allocations over the next few decades. Although some of these allocations will be driven purely by legal requirements, almost all of the major objectives of the cleanup and economic transition missions involve choices among alternative pathways. This study examined the following questions: what risk information is needed to make good decisions at Hanford; how do those data needs compare to the set(s) of risk data that will be generated by regulatory compliance activities and various non-compliance studies that are also concerned with risk? This analysis examined the Hanford Site missions, the Hanford Strategic Plan, known stakeholder values, and the most important decisions that have to be made at Hanford to determine a minimum domain of risk information required to make good decisions that will withstand legal, political, and technical scrutiny. The primary risk categories include (1) public health, (2) occupational health and safety, (3) ecological integrity, (4) cultural-religious welfare, and (5) socio-economic welfare.

  10. Energy and Greenhouse Gas Emissions in China: Growth, Transition, and Institutional Change

    NASA Astrophysics Data System (ADS)

    Kahrl, Fredrich James

    support further improvements in efficiency and scale up renewable generation at an acceptable level of cost and reliability. Chapter 6 examines energy use and GHG emissions from nitrogen fertilizer use, arguing that energy use and GHG emissions from nitrogen fertilizer use in China are high relative to other countries because of China's historical support for small and medium-sized enterprises using domestic technology; its continued provision of energy subsidies to fertilizer producers; and its lack of a well-functioning agricultural extension system. The case studies illustrate the limits of energy and climate policy in China without institutional reform. China's leaders have historically relied on economic growth to defer the difficult changes in political economy that accompany economic and social transition. However, many of the challenges of energy and climate policy require political decisions that reallocate resources among stakeholders. For instance, restructuring the Chinese economy away from heavy industrial investment and toward a higher GDP share of consumption will require financial sector reforms, such as interest rate liberalization or higher dividend payments for state-owned enterprises, that reallocate income from the industrial sector to households. Increasing power system flexibility will require price reforms that reallocate revenues and costs among generators, between generators and the grid companies, between producers and ratepayers, among ratepayer classes, and between and among provinces. Strong public interest institutions are needed to make these changes, which suggests that China's energy and GHG emissions trajectories will be determined, to a large extent, by the politics of institutional reform.

  11. Energy Transition Initiative: Island Energy Snapshot - U.S. Virgin Islands (Fact Sheet)

    SciTech Connect

    Not Available

    2015-03-01

    This profile provides a snapshot of the energy landscape of the U.S. Virgin Islands (USVI) - St. Thomas, St. John, and St. Croix. The Virgin Islands archipelago makes up the northern portion of the Lesser Antilles and the western island group of the Leeward Islands, forming the border between the Atlantic Ocean and the Caribbean Sea.

  12. Energy surface and minimum energy paths for Fréedericksz transitions in bistable cholesteric liquid crystals

    NASA Astrophysics Data System (ADS)

    Ivanov, A. V.; Bessarab, P. F.; Aksenova, E. V.; Romanov, V. P.; Uzdin, V. M.

    2016-04-01

    The multidimensional energy surface of a cholesteric liquid crystal in a planar cell is investigated as a function of spherical coordinates determining the director orientation. Minima on the energy surface correspond to the stable states with particular director distribution. External electric and magnetic fields deform the energy surface and positions of minima. It can lead to the transitions between states, known as the Fréedericksz effect. Transitions can be continuous or discontinuous depending on parameters of the liquid crystal which determine an energy surface. In a case of discontinuous transition when a barrier between stable states is comparable with the thermal energy, the activation transitions may occur, and it leads to the modification of characteristics of the Fréedericksz effect with temperature without explicit temperature dependencies of liquid crystal parameters. A minimum energy path between stable states on the energy surface for the Fréedericksz transition is found using the geodesic nudged elastic band method. Knowledge of this path, which has maximal statistical weight among all other paths, gives the information about a barrier between stable states and configuration of director orientation during the transition. It also allows one to estimate the stability of states with respect to the thermal fluctuations and their lifetime when the system is close to the Fréedericksz transition.

  13. Emittance and Energy Measurements of Low-Energy Electron Beam Using Optical Transition Radiation Techniques

    NASA Astrophysics Data System (ADS)

    Sakamoto, Fumito; Iijima, Hokuto; Dobashi, Katsuhiro; Imai, Takayuki; Ueda, Toru; Watanabe, Takahiro; Uesaka, Mitsuru

    2005-03-01

    Emittance and energy of an electron beam in the range of 8 to 22 MeV were measured via optical transition radiation (OTR) techniques. The beam divergence effect on observations of the far-field OTR image at low energies was studied by means of numerical analysis. The numerical analysis indicates that if the beam divergence is under 1.5 mrad, a simultaneous single-shot measurement of emittance and energy is possible. The results of the single-shot experiment agree with independent measurements conducted using the quadrupole scan method and an electron spectrometer. The experiments were performed with an S-band linac at the Nuclear Engineering Research Laboratory, The University of Tokyo (UTNL).

  14. Exploring Agricultural Livelihood Transitions with an Agent-Based Virtual Laboratory: Global Forces to Local Decision-Making

    PubMed Central

    Magliocca, Nicholas R.; Brown, Daniel G.; Ellis, Erle C.

    2013-01-01

    Rural populations are undergoing rapid changes in both their livelihoods and land uses, with associated impacts on ecosystems, global biogeochemistry, and climate change. A primary challenge is, thus, to explain these shifts in terms of the actors and processes operating within a variety of land systems in order to understand how land users might respond locally to future changes in broader-scale environmental and economic conditions. Using ‘induced intensification’ theory as a benchmark, we develop a generalized agent-based model to investigate mechanistic explanations of relationships between agricultural intensity and population density, environmental suitability, and market influence. Land-use and livelihood decisions modeled from basic micro-economic theories generated spatial and temporal patterns of agricultural intensification consistent with predictions of induced intensification theory. Further, agent actions in response to conditions beyond those described by induced intensification theory were explored, revealing that interactions among environmental constraints, population pressure, and market influence may produce transitions to multiple livelihood regimes of varying market integration. The result is new hypotheses that could modify and enrich understanding of the classic relationship between agricultural intensity and population density. The strength of this agent-based model and the experimental results is the generalized form of the decision-making processes underlying land-use and livelihood transitions, creating the prospect of a virtual laboratory for systematically generating hypotheses of how agent decisions and interactions relate to observed land-use and livelihood patterns across diverse land systems. PMID:24039892

  15. Exploring agricultural livelihood transitions with an agent-based virtual laboratory: global forces to local decision-making.

    PubMed

    Magliocca, Nicholas R; Brown, Daniel G; Ellis, Erle C

    2013-01-01

    Rural populations are undergoing rapid changes in both their livelihoods and land uses, with associated impacts on ecosystems, global biogeochemistry, and climate change. A primary challenge is, thus, to explain these shifts in terms of the actors and processes operating within a variety of land systems in order to understand how land users might respond locally to future changes in broader-scale environmental and economic conditions. Using 'induced intensification' theory as a benchmark, we develop a generalized agent-based model to investigate mechanistic explanations of relationships between agricultural intensity and population density, environmental suitability, and market influence. Land-use and livelihood decisions modeled from basic micro-economic theories generated spatial and temporal patterns of agricultural intensification consistent with predictions of induced intensification theory. Further, agent actions in response to conditions beyond those described by induced intensification theory were explored, revealing that interactions among environmental constraints, population pressure, and market influence may produce transitions to multiple livelihood regimes of varying market integration. The result is new hypotheses that could modify and enrich understanding of the classic relationship between agricultural intensity and population density. The strength of this agent-based model and the experimental results is the generalized form of the decision-making processes underlying land-use and livelihood transitions, creating the prospect of a virtual laboratory for systematically generating hypotheses of how agent decisions and interactions relate to observed land-use and livelihood patterns across diverse land systems.

  16. Examining Longitudinal Relationships between Dysfunctional Career Thoughts and Career Decision-Making Self-Efficacy in School-to-Work Transition

    ERIC Educational Resources Information Center

    Kim, Boyoung; Lee, Bo Hyun; Ha, Gyuyoung; Lee, Hong Kwon; Lee, Sang Min

    2015-01-01

    This study examines the role of dysfunctional career thoughts between two-wave longitudinal data (Time 1 and Time 2) in career decision-making self-efficacy during school-to-work transition periods. Career decision-making self-efficacy was measured before (Time 1) and after college graduation (Time 2). The results indicated that the growth of…

  17. Thermal energy storage device and method for making the same

    SciTech Connect

    Campbell, S.

    1983-06-21

    The thermal energy storage device is in the form of a sealed tube -like container such as a tube-like cylinder or other geometrical configuration partially filled with a phase change material such as calcium chloride hexahydrate. The cylinder is made of tubular high density polyethylene and more particularly an ultra high molecular weight high density polyethylene having a molecular weight of about 500,000 to 700,000 which is tough, chemically resistant, withstands low and high temperatures, acts as a moisture vapor barrier and can be fused and sealed. The calcium hexahydrate is filled in an open top cylinder, closed at the bottom by dissolving two parts of calcium chloride dihydrate with one part of water to provide calcium chloride hexahydrate in liquid form. The cylinder is filled to about 90% by volume and a cap of the same material is then preheated to about fusion temperature. The open top of the cylinder is then brought up to fusion temperature and the cap is fused to it under pressure. The thermal energy storage device with the encapsulated calcium chloride hexahydrate can then be subjected to repeated freezethaw cycles. The latent heat of fusion is utilized with sensible heat in various types of usages such as solar heating, heat pump applications and the like. In another embodiment the cylinder may be pinch sealed at the bottom and top by fusion to provide a flat pinch. Modifications of pinch sealing to reduce distortion near the seal include x-shaped, y-shaped and wave-shaped pinch seal configurations. The tube-like container instead of being cylindrical may for ease in stacking and to present greater surface area take other geometrical configurations such as a generally oblong configuration with rounded sides.

  18. Method for making an aluminum or copper substrate panel for selective absorption of solar energy

    NASA Technical Reports Server (NTRS)

    Roberts, M. L.; Sharpe, M. H.; Krupnick, A. C. (Inventor)

    1978-01-01

    A panel is described for selectively absorbing solar energy comprising an aluminum substrate. A zinc layer was covered by a layer of nickel and an outer layer of solar energy absorbing nickel oxide or a copper substrate with a nickel layer. A layer of solar energy absorbing nickel oxide distal from the copper substrate was included. A method for making these panels is disclosed.

  19. Transition in Education: Policy Making and the Key Educational Policy Areas in the Central-European and Baltic Countries.

    ERIC Educational Resources Information Center

    Rado, Peter

    This report examines transition in educational systems and identifies key policy areas in Central-Eastern European countries. It summarizes policy implications of the transition process within the educational context of these countries. Chapter 1, "Transition and Education," outlines key characteristics of the transition process and describes the…

  20. Comparative evaluation of energy management models for transit systems. Final report Sep 80-Dec 83

    SciTech Connect

    Nene, V.D.

    1984-02-01

    Recent advances in solid state control technology have led to chopper-controlled propulsion systems in urban rail transit applications. Such systems offer the potential for superior train performance through increased train propulsion efficiency and reduced train operating costs. The present program sponsored by the Urban Mass Transportation Administration studies the energy consumption characteristics of an urban rail system equipped with transit cars having solid-state chopper-controlled propulsion systems. The program objectives include the measurement of the transit system energy consumption during revenue and nonrevenue service operation and the study of the relative accuracy of current energy management models for predicting energy consumption in urban rail systems. This report summarizes the program accomplishments in the Bay Area Rapid Transit (BART) energy consumption tests and the validation of energy management models developed by private industry. The energy consumption of BART transit cars was measured with and without regeneration during the period of August 25, 1981 through September 2, 1981. The test data was then compared with the predictions of different energy management models currently in use for transit system studies. This report presents the results of the comparative evaluation of these models.

  1. Heats of solution and lattice-expansion and trapping energies of hydrogen in transition metals

    NASA Astrophysics Data System (ADS)

    Griessen, R.

    1988-08-01

    The heat of hydrogen solution in a metal at infinite dilution ΔH¯∞ is shown to depend on (1) the distance R between a hydrogen atom and its metallic nearest neighbors, (2) the characteristic band-structure energy ΔE=EF-Es, where EF is the Fermi energy and Es basically the center of the lowest conduction band of the host metal, and (3) the width Wd of the d band of the host metal. The semiempirical relation ΔH¯∞=αΔE W1/2d [with α=18.6 (kJ/mol H)(AṨ eV-3/2) and β=-90 kJ/mol H if ΔE, Wd, and R are given in units of eV and Å, respectively] reproduces the experimental values of ΔH¯∞ remarkably well. It also reproduces the volume expansion accompanying hydrogen absorption and predicts the correct interstitial site occupancy of hydrogen in a transition metal. Furthermore, it makes it possible to estimate the binding energy of hydrogen to a vacancy.

  2. Large impact of reorganization energy on photovoltaic conversion due to interfacial charge-transfer transitions.

    PubMed

    Fujisawa, Jun-ichi

    2015-05-14

    Interfacial charge-transfer (ICT) transitions are expected to be a novel charge-separation mechanism for efficient photovoltaic conversion featuring one-step charge separation without energy loss. Photovoltaic conversion due to ICT transitions has been investigated using several TiO2-organic hybrid materials that show organic-to-inorganic ICT transitions in the visible region. In applications of ICT transitions to photovoltaic conversion, there is a significant problem that rapid carrier recombination is caused by organic-inorganic electronic coupling that is necessary for the ICT transitions. In order to solve this problem, in this work, I have theoretically studied light-to-current conversions due to the ICT transitions on the basis of the Marcus theory with density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations. An apparent correlation between the reported incident photon-to-current conversion efficiencies (IPCE) and calculated reorganization energies was clearly found, in which the IPCE increases with decreasing the reorganization energy consistent with the Marcus theory in the inverted region. This activation-energy dependence was systematically explained by the equation formulated by the Marcus theory based on a simple excited-state kinetic scheme. This result indicates that the reduction of the reorganization energy can suppress the carrier recombination and enhance the IPCE. The reorganization energy is predominantly governed by the structural change in the chemical-adsorption moiety between the ground and ICT excited states. This work provides crucial knowledge for efficient photovoltaic conversion due to ICT transitions.

  3. [Transition to adult care for children with chronic neurological disorders; which is the best way to make it?].

    PubMed

    Moreno Villares, José Manuel

    2014-01-01

    Chronic neurological disorders in children have significant effects on adult medical and social function. Transition from pediatric to adult services is a complex process. No objective data are available to inform physicians about the most effective approach. Nevertheless the most recommended approach is a joint pediatric/adult transition clinic. Malnutrition, either under or overnutrition, is a common condition among neurologically impaired children. Undernutrition is most prevalent, and its causes are diverse: insufficient caloric intake, excessive nutrient losses and abnormal energy metabolism. Malnutrition is associated with significant morbidity, while nutritional rehabilitation improves overall health as well as quality of life. It is not easy to determine which the nutritional needs in these patients are. Besides, they often present difficulties for oral feeding, mainly due to oromotor dysfunction. Gastrointestinal symptoms, gastro esophageal reflux and constipation, as well as spasticity, scoliosis and joint deformities contribute to these difficulties. Because of that, an assessment of nutritional status should be performed periodically, and to assess efficacy and security of oral intake. If modifying oral diet we cannot confirm an adequate support, a nasogastric tube or a gastrostomy need to be considered. Often, a fundoplication is associated to the placement of a gastrostomy. Although the outcomes in a better nutritional status and quality of life are often obtained, it is not an easy decision for families. PMID:25077342

  4. Control of valence and conduction band energies in layered transition metal phosphates via surface functionalization.

    PubMed

    Lentz, Levi C; Kolb, Brian; Kolpak, Alexie M

    2016-05-18

    Layered transition metal phosphates and phosphites (TMPs) are a class of materials composed of layers of 2D sheets bound together via van der Waals interactions and/or hydrogen bonds. Explored primarily for use in proton transfer, their unique chemical tunability also makes TMPs of interest for forming large-scale hybrid materials. Further, unlike many layered materials, TMPs can readily be solution exfoliated to form single 2D sheets or bilayers, making them exciting candidates for a variety of applications. However, the electronic properties of TMPs have largely been unstudied to date. In this work, we use first-principles computations to investigate the atomic and electronic structure of TMPs with a variety of stoichiometries. We demonstrate that there exists a strong linear relationship between the band gap and the ionic radius of the transition metal cation in these materials, and show that this relationship, which opens opportunities for engineering new compositions with a wide range of band gaps, arises from constraints imposed by the phosphorus-oxygen bond geometry. In addition, we find that the energies of the valence and conduction band edges can be systematically tuned over a range of ∼3 eV via modification of the functional group extending from the phosphorus. Based on the Hammett constant of this functional group, we identify a simple, predictive relationship for the ionization potential and electron affinity of layered TMPs. Our results thus provide guidelines for systematic design of TMP-derived functional materials, which may enable new approaches for optimizing charge transfer in electronics, photovoltaics, electrocatalysts, and other applications. PMID:27157509

  5. Control of valence and conduction band energies in layered transition metal phosphates via surface functionalization.

    PubMed

    Lentz, Levi C; Kolb, Brian; Kolpak, Alexie M

    2016-05-18

    Layered transition metal phosphates and phosphites (TMPs) are a class of materials composed of layers of 2D sheets bound together via van der Waals interactions and/or hydrogen bonds. Explored primarily for use in proton transfer, their unique chemical tunability also makes TMPs of interest for forming large-scale hybrid materials. Further, unlike many layered materials, TMPs can readily be solution exfoliated to form single 2D sheets or bilayers, making them exciting candidates for a variety of applications. However, the electronic properties of TMPs have largely been unstudied to date. In this work, we use first-principles computations to investigate the atomic and electronic structure of TMPs with a variety of stoichiometries. We demonstrate that there exists a strong linear relationship between the band gap and the ionic radius of the transition metal cation in these materials, and show that this relationship, which opens opportunities for engineering new compositions with a wide range of band gaps, arises from constraints imposed by the phosphorus-oxygen bond geometry. In addition, we find that the energies of the valence and conduction band edges can be systematically tuned over a range of ∼3 eV via modification of the functional group extending from the phosphorus. Based on the Hammett constant of this functional group, we identify a simple, predictive relationship for the ionization potential and electron affinity of layered TMPs. Our results thus provide guidelines for systematic design of TMP-derived functional materials, which may enable new approaches for optimizing charge transfer in electronics, photovoltaics, electrocatalysts, and other applications.

  6. SunShot Initiative: Making Solar Energy Affordable for All Americans (Fact Sheet)

    SciTech Connect

    Not Available

    2013-10-01

    Through SunShot, DOE supports efforts by private companies, universities, and national laboratories to drive down the cost of solar electricity to $0.06 per kilowatt-hour, making solar energy affordable for more American families and businesses.

  7. Ultra-high energy physics and standard basic principles. Do Planck units really make sense?

    NASA Astrophysics Data System (ADS)

    Gonzalez-Mestres, Luis

    2014-04-01

    It has not yet been elucidated whether the observed flux suppression for ultra-high energy cosmic rays (UHECR) at energies above ≃ 4 x 1019 eV is a signature of the Greisen-Zatsepin-Kuzmin (GZK) cutoff or a consequence of other phenomena. In both cases, violations of the standard fundamental principles of Physics can be present and play a significant role. They can in particular modify cosmic-ray interactions, propagation or acceleration at very high energy. Thus, in a long-term program, UHECR data can hopefully be used to test relativity, quantum mechanics, energy and momentum conservation, vacuum properties... as well as the elementariness of standard particles. Data on cosmic rays at energies ≃ 1020 eV may also be sensitive to new physics generated well beyond Planck scale. A typical example is provided by the search for possible signatures of a Lorentz symmetry violation (LSV) associated to a privileged local reference frame (the "vacuum rest frame", VRF). If a VRF exists, the internal structure of standard particles at ultra-high energy can undergo substantial modifications. Similarly, the conventional particle symmetries may cease to be valid at such energies instead of heading to a grand unification and the structure of vacuum may no longer be governed by standard quantum field theory. Then, the question whether the notion of Planck scale still makes sense clearly becomes relevant and the very grounds of Cosmology can undergo essential modifications. UHECR studies naturally interact with the interpretation of WMAP and Planck observations. Recent Planck data analyses tend to confirm the possible existence of a privileged space direction. If the observed phenomenon turns out to be a signature of the spinorial space-time (SST) we suggested in 1996-97, then conventional Particle Physics may correspond to the local properties of standard matter at low enough energy and large enough distances. This would clearly strengthen the cosmological relevance of UHECR

  8. Requirements for supercomputing in energy research: The transition to massively parallel computing

    SciTech Connect

    Not Available

    1993-02-01

    This report discusses: The emergence of a practical path to TeraFlop computing and beyond; requirements of energy research programs at DOE; implementation: supercomputer production computing environment on massively parallel computers; and implementation: user transition to massively parallel computing.

  9. Fuel Cell Transit Bus Evaluations: Joint Evaluation Plan for the U.S. Department of Energy and the Federal Transit Administration (Report and Appendix)

    SciTech Connect

    Eudy, L.; Chandler, K.

    2010-11-01

    This document describes the fuel cell transit bus evaluations performed by the National Renewable Energy Laboratory (NREL) and funded by the U.S. Department of Energy (DOE) and the U.S. Department of Transportation's Federal Transit Administration (FTA). This document provides a description of the demonstration sites, funding sources, and data collection activities for fuel cell transit bus evaluations currently planned from FY10 through FY12.

  10. Scaling Relationships for Adsorption Energies of C2 Hydrocarbons on Transition Metal Surfaces

    SciTech Connect

    Jones, G

    2011-08-18

    Using density functional theory calculations we show that the adsorption energies for C{sub 2}H{sub x}-type adsorbates on transition metal surfaces scale with each other according to a simple bond order conservation model. This observation generalizes some recently recognized adsorption energy scaling laws for AH{sub x}-type adsorbates to unsaturated hydrocarbons and establishes a coherent simplified description of saturated as well as unsaturated hydrocarbons adsorbed on transition metal surfaces. A number of potential applications are discussed. We apply the model to the dehydrogenation of ethane over pure transition metal catalysts. Comparison with the corresponding full density functional theory calculations shows excellent agreement.

  11. Analytical expressions for partial wave two-body Coulomb transition matrices at ground-state energy

    NASA Astrophysics Data System (ADS)

    Kharchenko, V. F.

    2016-11-01

    Leaning upon the Fock method of the stereographic projection of the three-dimensional momentum space onto the four-dimensional unit sphere the possibility of the analytical solving of the Lippmann-Schwinger integral equation for the partial wave two-body Coulomb transition matrix at the ground bound state energy has been studied. In this case new expressions for the partial p-, d- and f-wave two-body Coulomb transition matrices have been obtained in the simple analytical form. The developed approach can also be extended to determine analytically the partial wave Coulomb transition matrices at the energies of excited bound states.

  12. Energy harvesting from localized dynamic transitions in post-buckled elastic beams under quasi-static loading

    NASA Astrophysics Data System (ADS)

    Borchani, Wassim

    The deployability of structural health monitoring self-powered sensors relies on their capability to harvest energy from signals being monitored. Many of the signals required to assess the structure condition are quasi-static events which limits the levels of power that can be extracted. Several vibration-based techniques have been proposed to increase the transferred level of power and broaden the harvester operating bandwidth. However, these techniques require vibration input excitations at frequencies higher than dominant structural response frequencies which makes them inefficient and not suitable for ambient quasi-static excitations. This research proposes a novel sensing and energy harvesting technique at low frequencies using mechanical energy concentrators and triggers. These mechanisms consist of axially-loaded bilaterally-constrained beams with attached piezoelectric energy harvesters. When the quasi-static axial load reaches a certain mechanical threshold, a sudden snap-through mode-switching occurs. These transitions excite the attached piezoelectric scavengers with high-rate input accelerations, generating then electric power. The main objectives are to understand and model the post-buckling behavior of bilaterally-constrained beams, control it by tailoring geometry and material properties of the buckled elements or stacking them into system assemblies, and finally characterize the energy harvesting and sensing capability of the system under quasi-static excitations. The fundamental principle relies on the following concept. Under axial load, a straight slender beam buckles in the first buckling mode. The increased transverse deformations from a buckled shape lead to contact interaction with the lateral boundaries. The contact interaction generates transverse forces that induce the development of higher order buckling configurations. Transitions between the buckled configurations occur not only during loading, but also unloading. In this work, the post

  13. Power lines: Urban space, energy development and the making of the modern Southwest

    NASA Astrophysics Data System (ADS)

    Needham, Todd Andrew

    "Power Lines: Urban Space, Energy Development, and the Making of the Modern Southwest" explores the social and environmental transformation of the postwar Southwest and the resulting disputes between urban boosters, federal officials, Native Americans, and environmental activists. The dissertation focuses on the infrastructure built to provide the burgeoning populations of Phoenix, Los Angeles, and other Southwestern cities with electricity. This infrastructure allowed metropolitan boosters in the Southwest to attract Cold War defense manufacturing and to build a new suburban landscape even as industrialization on Indian lands provided electricity for those landscapes. Tracing the transition of electrical generation from a dispersed geography relying on local resources to a centralized geography utilizing primarily coal from Navajo land, "Power Lines" demonstrates the increasing centrality of Indian lands and labor to the metropolitan Southwest. Paying close attention to these networks reveals the far-reaching changes caused by postwar metropolitan growth. "Power Lines" challenges understandings of urban space that neglect the material resources that allow cities to "live." As the nation's cities and suburbs became increasingly energy-intensive, electrical utilities reached deep into the metropolitan periphery, transforming landscapes hundreds of miles from city centers into urban space. The construction of the new "geography of power" in the Southwest also reflects the impact of growth liberalism on postwar growth, as federal money funded suburban, manufacturing, and infrastructure developments. This pursuit of growth produced new political struggles, both as the development of energy resources conflicted with emerging environmentalist sensibilities and as American Indians increasingly resented the industrialization of their land for the benefit of others. By the 1970s, the simultaneous pursuit and criticism of growth came to define the modern Southwest. The

  14. Activation energy for a model ferrous-ferric half reaction from transition path sampling.

    PubMed

    Drechsel-Grau, Christof; Sprik, Michiel

    2012-01-21

    Activation parameters for the model oxidation half reaction of the classical aqueous ferrous ion are compared for different molecular simulation techniques. In particular, activation free energies are obtained from umbrella integration and Marcus theory based thermodynamic integration, which rely on the diabatic gap as the reaction coordinate. The latter method also assumes linear response, and both methods obtain the activation entropy and the activation energy from the temperature dependence of the activation free energy. In contrast, transition path sampling does not require knowledge of the reaction coordinate and directly yields the activation energy [C. Dellago and P. G. Bolhuis, Mol. Simul. 30, 795 (2004)]. Benchmark activation energies from transition path sampling agree within statistical uncertainty with activation energies obtained from standard techniques requiring knowledge of the reaction coordinate. In addition, it is found that the activation energy for this model system is significantly smaller than the activation free energy for the Marcus model, approximately half the value, implying an equally large entropy contribution.

  15. The Role of Grain Boundary Energy on Grain Boundary Complexion Transitions

    SciTech Connect

    Bojarski, Stephanie A.; Rohrer, Gregory S.

    2014-09-01

    Grain boundary complexions are distinct equilibrium structures and compositions of a grain boundary and complexion transformations are transition from a metastable to an equilibrium complexion at a specific thermodynamic and geometric conditions. Previous work indicates that, in the case of doped alumina, a complexion transition that increased the mobility of transformed boundaries and resulted in abnormal grain growth also caused a decrease in the mean relative grain boundary energy as well as an increase in the anisotropy of the grain boundary character distribution (GBCD). The current work will investigate the hypothesis that the rates of complexion transitions that result in abnormal grain growth (AGG) depend on grain boundary character and energy. Furthermore, the current work expands upon this understanding and tests the hypothesis that it is possible to control when and where a complexion transition occurs by controlling the local grain boundary energy distribution.

  16. Treatment of Electronic Energy Level Transition and Ionization Following the Particle-Based Chemistry Model

    NASA Technical Reports Server (NTRS)

    Liechty, Derek S.; Lewis, Mark

    2010-01-01

    A new method of treating electronic energy level transitions as well as linking ionization to electronic energy levels is proposed following the particle-based chemistry model of Bird. Although the use of electronic energy levels and ionization reactions in DSMC are not new ideas, the current method of selecting what level to transition to, how to reproduce transition rates, and the linking of the electronic energy levels to ionization are, to the author s knowledge, novel concepts. The resulting equilibrium temperatures are shown to remain constant, and the electronic energy level distributions are shown to reproduce the Boltzmann distribution. The electronic energy level transition rates and ionization rates due to electron impacts are shown to reproduce theoretical and measured rates. The rates due to heavy particle impacts, while not as favorable as the electron impact rates, compare favorably to values from the literature. Thus, these new extensions to the particle-based chemistry model of Bird provide an accurate method for predicting electronic energy level transition and ionization rates in gases.

  17. Energy Transition Initiative: Island Energy Snapshot - Puerto Rico (Fact Sheet); NREL(National Renewable Energy Laboratory)

    SciTech Connect

    2015-03-01

    This profile provides a snapshot of the energy landscape of the Commonwealth of Puerto Rico - a U.S. territory located about 60 miles east of the Dominican Republic and directly west of the U.S. Virgin Islands.

  18. Correlation between oxygen adsorption energy and electronic structure of transition metal macrocyclic complexes

    NASA Astrophysics Data System (ADS)

    Liu, Kexi; Lei, Yinkai; Wang, Guofeng

    2013-11-01

    Oxygen adsorption energy is directly relevant to the catalytic activity of electrocatalysts for oxygen reduction reaction (ORR). In this study, we established the correlation between the O2 adsorption energy and the electronic structure of transition metal macrocyclic complexes which exhibit activity for ORR. To this end, we have predicted the molecular and electronic structures of a series of transition metal macrocyclic complexes with planar N4 chelation, as well as the molecular and electronic structures for the O2 adsorption on these macrocyclic molecules, using the density functional theory calculation method. We found that the calculated adsorption energy of O2 on the transition metal macrocyclic complexes was linearly related to the average position (relative to the lowest unoccupied molecular orbital of the macrocyclic complexes) of the non-bonding d orbitals (d_{z^2 }, d_{xy}, d_{xz}, and dyz) which belong to the central transition metal atom. Importantly, our results suggest that varying the energy level of the non-bonding d orbitals through changing the central transition metal atom and/or peripheral ligand groups could be an effective way to tuning their O2 adsorption energy for enhancing the ORR activity of transition metal macrocyclic complex catalysts.

  19. Energy levels and multipole transition properties of C4+ ion in Debye plasmas

    NASA Astrophysics Data System (ADS)

    Xie, L. Y.; Wang, J. G.; Janev, R. K.; Qu, Y. Z.; Dong, C. Z.

    2012-05-01

    Plasma screening effects on the energy structure and radiative transition properties of helium-like C4+ ions embedded in Debye plasmas are investigated by using the multi-configuration Dirac-Hartree-Fock method incorporating the Debye-Hückel potential for both the electron-nucleus and electron-electron interactions. Seventeen fine-structure energy levels of the low-lying 1 s 2, 1 s2 l( l = s,p) and 1 s3 l'( l' = s,p,d) configurations, as well as the electric-dipole ( E1), magnetic-dipole ( M1) and magnetic-quadrupole ( M2) transition probabilities and oscillator strengths between these levels have been calculated over a wide range of screening parameters. It is found that the plasma screening leads to a decrease of excitation energies and alters the energy levels remarkably. For Δn ≠ 0 transitions, the spontaneous decay spectra are red-shifted and their oscillator strengths and transition probabilities decrease with increasing the interaction screening, while those for the Δn = 0 transitions exhibit opposite patterns. The influence of electron-nucleus and electron-electron screened interactions on the changes of energy levels and transition properties are analyzed. Comparison is made of present results with other data available in the literature for this ion.

  20. Correlation between oxygen adsorption energy and electronic structure of transition metal macrocyclic complexes

    SciTech Connect

    Liu, Kexi; Lei, Yinkai; Wang, Guofeng

    2013-11-28

    Oxygen adsorption energy is directly relevant to the catalytic activity of electrocatalysts for oxygen reduction reaction (ORR). In this study, we established the correlation between the O{sub 2} adsorption energy and the electronic structure of transition metal macrocyclic complexes which exhibit activity for ORR. To this end, we have predicted the molecular and electronic structures of a series of transition metal macrocyclic complexes with planar N{sub 4} chelation, as well as the molecular and electronic structures for the O{sub 2} adsorption on these macrocyclic molecules, using the density functional theory calculation method. We found that the calculated adsorption energy of O{sub 2} on the transition metal macrocyclic complexes was linearly related to the average position (relative to the lowest unoccupied molecular orbital of the macrocyclic complexes) of the non-bonding d orbitals (d{sub z{sup 2}}, d{sub xy}, d{sub xz}, and d{sub yz}) which belong to the central transition metal atom. Importantly, our results suggest that varying the energy level of the non-bonding d orbitals through changing the central transition metal atom and/or peripheral ligand groups could be an effective way to tuning their O{sub 2} adsorption energy for enhancing the ORR activity of transition metal macrocyclic complex catalysts.

  1. Transition report, United States Department of Energy: A report to the President-Elect. Volume 2

    SciTech Connect

    Not Available

    1988-11-01

    This report is a description of the Department of Energy transition issues. The topics of the report include: Congressional, Intergovernmental and Public Affairs; Conservation and Renewable Energy; Defense Programs; New Production Reactors; Economic Regulatory Administration; Energy Information Administration; energy research; environment, safety and health; fossil energy; General Counsel; hearings and appeals, Inspector General, international affairs and energy emergencies; management and administration, minority economic impact; nuclear energy; policy, planning and analysis, radioactive waste management; and power marketing administrations: Bonneville Power Administration, Western Area Power Administration, Alaska Power Administration, Southeastern Power Administration, and Southwestern Power Administration.

  2. Energy in New England: Transition to the 80's

    NASA Astrophysics Data System (ADS)

    Katz, R.; Pawlick, L.; Spencer, B.

    1981-06-01

    Activities in New England which result in more efficient consumption of energy are discussed. Change in aggregate energy demand since the oil embargo, energy use and the regional economy, incentives for conservation, and decline in electricity growth are also discussed. The conributions made by wood products, hydroelectric power, solid waste, solar, wind, alcohol fuels, peat, and tidal power are disclosed. Changes in consumption of individual conventional energy products (petroleum, natural gas, nuclear power, coal, purchased electricity) and activity currently underway in the conventional fuel area are summarized.

  3. Reference free, high-precision measurements of transition energies in few electron argon ions

    NASA Astrophysics Data System (ADS)

    Szabo, Csilla I.; Amaro, Pedro; Guerra, Mauro; Schlesser, Sophie; Gumberidze, Alexander; Santos, José Paulo; Indelicato, Paul

    2013-04-01

    The use of a vacuum double crystal spectrometer, coupled to an electron-cyclotron resonance ion source (ECRIS), allows to measure low-energy x-ray transitions energies in highly-charged ions with accuracies of the order of a few parts per million. We have used this installation to measure the 1s2p 1 P1 → 1s2 1 S0 diagram line and the 1s2s 3 S1 → 1s2 1 S0 forbidden M1 transition energies in helium-like argon, the 1s2s2p 2 Pj → 1s2 2s 2 S1/2 transitions in lithium-like argon and the 1s2s2 2p 1 P1 → 1s2 2s2 1 S0 transition in beryllium-like argon. These transition measurements have accuracies between 2 and 4 ppm depending on the line intensity. Thanks to the excellent agreement between the simulations and the measurements, we were also able to measure the transition width of all the allowed transitions. The results are compared to recent QED and relativistic many-body calculations.

  4. IBS and possible luminosity improvement for RHIC operation below transition energy

    SciTech Connect

    Fedotov,A.V.

    2009-05-04

    There is a strong interest in low-energy RHIC collisions in the energy range below present RHIC transition energy. These collisions win help to answer one of the key questions in the field of QCD about the existence and location of a critical point on the QCD phase diagram. For such low-energy RHIC operation, particle losses from the RF bucket are of particular concern since the longitudinal beam size is comparable to the existing RF bucket at low energies. In this paper, we explore an Intrabeam Scattering (IBS) feature below transition energy that drives the transverse and longitudinal beam temperatures towards equilibrium to see whether we can minimize longitudinal diffusion due to IBS and predict some luminosity improvement for the low-energy RHIC project.

  5. Energy Independence for North America - Transition to the Hydrogen Economy

    SciTech Connect

    Eberhardt, J.

    2003-08-24

    The U.S. transportation sector is almost totally dependent on liquid hydrocarbon fuels, primarily gasoline and diesel fuel from conventional oil. In 2002, the transportation sector accounted for 69 percent of the U.S. oil use; highway vehicles accounted for 54 percent of the U.S. oil use. Of the total energy consumed in the U.S., more than 40 percent came from oil. More significantly, more than half of this oil is imported and is projected by the Energy Information Agency (EIA) to increase to 68 percent by 2025 [1]. The supply and price of oil have been dictated by the Organization of Petroleum Exporting Countries (OPEC). In 2002, OPEC accounted for 39 percent of world oil production and this is projected by the EIA to increase to 50 percent in 2025. Of the world's oil reserves, about 80 percent is owned by OPEC members. Major oil price shocks have disrupted world energy markets four times in the past 30 years (1973-74, 1979-80, 1990-1991, and 1999- 2000) and with each came either a recession or slowdown in the GDP (Gross Domestic Product) of the United States. In addition, these market upheavals have cost the U.S. approximately $7 trillion (in 1998 dollars) in total economic costs [2]. Finally, it is estimated that military expenditures for defending oil supplies in the Middle East range from $6 billion to $60 billion per year [3] and do not take into account the costs of recent military operations in Iraq (i.e., Operation Iraqi Freedom, 2003). At the outset of his administration in 2001, President George W. Bush established the National Energy Policy Development (NEPD) Group to develop a national energy policy to promote dependable, affordable, and environmentally sound energy for the future in order to avert potential energy crises. In the National Energy Policy report [4], the NEPD Group urges action by the President to meet five specific national goals that America must meet--''modernize conservation, modernize our energy infrastructure, increase energy

  6. Energy Transition Initiative: Island Energy Snapshot - Trinidad and Tobago; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-05-20

    This profile provides a snapshot of the energy landscape of Trinidad and Tobago, a two-island nation located off the coast of Venezuela. Trinidad and Tobago’s electricity rates are some of the lowest in the Caribbean at approximately $0.04 per kilowatt-hour (kWh), well below the regional average of $0.33/kWh.

  7. Energy Transition Initiative: Island Energy Snapshot - Antigua and Barbuda; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-05-20

    This profile provides a snapshot of the energy landscape of Antigua and Barbuda, an independent nation in the Leeward Islands in the eastern Caribbean Sea. Antigua and Barbuda’s utility rates are approximately $0.37 U.S. dollars (USD) per kilowatt-hour (kWh), which is above the Caribbean regional average of $0.33 USD/kWh.

  8. Energy Transition Initiative: Island Energy Snapshot - Guadeloupe; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-05-27

    This profile provides a snapshot of the energy landscape of Guadeloupe, an overseas region of France located in the eastern Caribbean Sea. Guadeloupe’s utility rates are approximately $0.18 U.S. dollars (USD) per kilowatt-hour (kWh), below the Caribbean regional average of $0.33 USD/kWh.

  9. High-pressure phase transition makes B4.3C boron carbide a wide-gap semiconductor.

    PubMed

    Hushur, Anwar; Manghnani, Murli H; Werheit, Helmut; Dera, Przemyslaw; Williams, Quentin

    2016-02-01

    Single-crystal B4.3C boron carbide is investigated through the pressure-dependence and inter-relation of atomic distances, optical properties and Raman-active phonons up to ~70 GPa. The anomalous pressure evolution of the gap width to higher energies is striking. This is obtained from observations of transparency, which most rapidly increases around 55 GPa. Full visible optical transparency is approached at pressures of  >60 GPa indicating that the band gap reaches ~3.5 eV; at high pressure, boron carbide is a wide-gap semiconductor. The reason is that the high concentration of structural defects controlling the electronic properties of boron carbide at ambient conditions initially decreases and finally vanishes at high pressures. The structural parameters and Raman-active phonons indicate a pressure-dependent phase transition in single-crystal (nat)B4.3C boron carbide near 40 GPa, likely related to structural changes in the C-B-C chains, while the basic icosahedral structure appears to be less affected.

  10. High-pressure phase transition makes B4.3C boron carbide a wide-gap semiconductor

    NASA Astrophysics Data System (ADS)

    Hushur, Anwar; Manghnani, Murli H.; Werheit, Helmut; Dera, Przemyslaw; Williams, Quentin

    2016-02-01

    Single-crystal B4.3C boron carbide is investigated through the pressure-dependence and inter-relation of atomic distances, optical properties and Raman-active phonons up to ~70 GPa. The anomalous pressure evolution of the gap width to higher energies is striking. This is obtained from observations of transparency, which most rapidly increases around 55 GPa. Full visible optical transparency is approached at pressures of  >60 GPa indicating that the band gap reaches ~3.5 eV at high pressure, boron carbide is a wide-gap semiconductor. The reason is that the high concentration of structural defects controlling the electronic properties of boron carbide at ambient conditions initially decreases and finally vanishes at high pressures. The structural parameters and Raman-active phonons indicate a pressure-dependent phase transition in single-crystal natB4.3C boron carbide near 40 GPa, likely related to structural changes in the C-B-C chains, while the basic icosahedral structure appears to be less affected.

  11. Beyond the Chinese Dream: How Women Executives Working in Multinational Corporations in the People's Republic of China Describe and Make Meaning of Midlife Transition

    ERIC Educational Resources Information Center

    Woo, Marjorie J.

    2012-01-01

    The purpose of this study is to gain understanding of Chinese women executives going beyond the Chinese dream, to learn how they describe and make meaning of their midlife transition experience. A narrative inquiry and holistic content and form approach was used to explore two-stage life stories: narratives of self-actualization of women…

  12. Mathematical Under-Preparedness: The Influence of the Pre-Tertiary Mathematics Experience on Students' Ability to Make a Successful Transition to Tertiary Level Mathematics Courses in Ireland

    ERIC Educational Resources Information Center

    Hourigan, M.; O'Donoghue, J.

    2007-01-01

    Internationally, the consequences of the "Mathematics problem" are a source of concern for the education sector and governments alike. Growing consensus exists that the inability of students to successfully make the transition to tertiary level mathematics education lies in the substantial mismatch between the nature of entrants' pre-tertiary…

  13. Modeling and control of distributed energy systems during transition between grid connected and standalone modes

    NASA Astrophysics Data System (ADS)

    Arafat, Md Nayeem

    Distributed generation systems (DGs) have been penetrating into our energy networks with the advancement in the renewable energy sources and energy storage elements. These systems can operate in synchronism with the utility grid referred to as the grid connected (GC) mode of operation, or work independently, referred to as the standalone (SA) mode of operation. There is a need to ensure continuous power flow during transition between GC and SA modes, referred to as the transition mode, in operating DGs. In this dissertation, efficient and effective transition control algorithms are developed for DGs operating either independently or collectively with other units. Three techniques are proposed in this dissertation to manage the proper transition operations. In the first technique, a new control algorithm is proposed for an independent DG which can operate in SA and GC modes. The proposed transition control algorithm ensures low total harmonic distortion (THD) and less voltage fluctuation during mode transitions compared to the other techniques. In the second technique, a transition control is suggested for a collective of DGs operating in a microgrid system architecture to improve the reliability of the system, reduce the cost, and provide better performance. In this technique, one of the DGs in a microgrid system, referred to as a dispatch unit , takes the additional responsibility of mode transitioning to ensure smooth transition and supply/demand balance in the microgrid. In the third technique, an alternative transition technique is proposed through hybridizing the current and droop controllers. The proposed hybrid transition control technique has higher reliability compared to the dispatch unit concept. During the GC mode, the proposed hybrid controller uses current control. During the SA mode, the hybrid controller uses droop control. During the transition mode, both of the controllers participate in formulating the inverter output voltage but with different

  14. A new US energy agenda: US leadership in transition

    SciTech Connect

    Not Available

    1992-11-20

    For the first time since the Carter Administration at the end of 1980, the US is embarked upon energy management beyond laissez faire' free market determination. The election of Bill Clinton to the Presidency could mean the release of years-old pressures to greatly increase efficiency, dramatically reduce hydrocarbon dependency, and curtail pollution to unheard of degrees. Doubtlessly, it will also unleash debates about how to do this without imposing protectionism or further slowing the domestic economy. In this issue a veteran energy analyst, J. Lange Winckler, assesses the changes to be expected. ED supplements the text with graphics that illustrate four scenarios of energy growth and utilization over the next 40 years. This issue also includes the following: (1) the ED Refining Netback Data for the US Gulf and West Coasts, Rotterdam and Singapore as of November 6, 1992; and (2) the ED Fuel Price/Tax Series for countries of the Western Hemisphere, November 1992 Edition.

  15. Are We There Yet? Making the Successful Transition to Adulthood. Longitudinal Surveys of Australian Youth. Research Synthesis

    ERIC Educational Resources Information Center

    National Centre for Vocational Education Research (NCVER), 2011

    2011-01-01

    There was a time when leaving school marked the beginning of adulthood. Even though this transition has now lengthened, the traditional markers of a successful transition remain the same: getting a good job, becoming a responsible citizen, establishing a household and having a family. Being either in full-time education or work, or a combination…

  16. The Life Course in the Making: Gender and the Development of Adolescents' Expected Timing of Adult Role Transitions

    ERIC Educational Resources Information Center

    Crockett, Lisa J.; Beal, Sarah J.

    2012-01-01

    Adolescents' expectations about the timing of adult role transitions have the potential to shape their actual transitions, setting the stage for their adult lives. Although expectations about timing emerge by early adolescence, little is known about how these expectations develop across adolescence. This longitudinal study examined developmental…

  17. Porous nanoarchitectures of spinel-type transition metal oxides for electrochemical energy storage systems.

    PubMed

    Park, Min-Sik; Kim, Jeonghun; Kim, Ki Jae; Lee, Jong-Won; Kim, Jung Ho; Yamauchi, Yusuke

    2015-12-14

    Transition metal oxides possessing two kinds of metals (denoted as AxB3-xO4, which is generally defined as a spinel structure; A, B = Co, Ni, Zn, Mn, Fe, etc.), with stoichiometric or even non-stoichiometric compositions, have recently attracted great interest in electrochemical energy storage systems (ESSs). The spinel-type transition metal oxides exhibit outstanding electrochemical activity and stability, and thus, they can play a key role in realising cost-effective and environmentally friendly ESSs. Moreover, porous nanoarchitectures can offer a large number of electrochemically active sites and, at the same time, facilitate transport of charge carriers (electrons and ions) during energy storage reactions. In the design of spinel-type transition metal oxides for energy storage applications, therefore, nanostructural engineering is one of the most essential approaches to achieving high electrochemical performance in ESSs. In this perspective, we introduce spinel-type transition metal oxides with various transition metals and present recent research advances in material design of spinel-type transition metal oxides with tunable architectures (shape, porosity, and size) and compositions on the micro- and nano-scale. Furthermore, their technological applications as electrode materials for next-generation ESSs, including metal-air batteries, lithium-ion batteries, and supercapacitors, are discussed.

  18. Porous nanoarchitectures of spinel-type transition metal oxides for electrochemical energy storage systems.

    PubMed

    Park, Min-Sik; Kim, Jeonghun; Kim, Ki Jae; Lee, Jong-Won; Kim, Jung Ho; Yamauchi, Yusuke

    2015-12-14

    Transition metal oxides possessing two kinds of metals (denoted as AxB3-xO4, which is generally defined as a spinel structure; A, B = Co, Ni, Zn, Mn, Fe, etc.), with stoichiometric or even non-stoichiometric compositions, have recently attracted great interest in electrochemical energy storage systems (ESSs). The spinel-type transition metal oxides exhibit outstanding electrochemical activity and stability, and thus, they can play a key role in realising cost-effective and environmentally friendly ESSs. Moreover, porous nanoarchitectures can offer a large number of electrochemically active sites and, at the same time, facilitate transport of charge carriers (electrons and ions) during energy storage reactions. In the design of spinel-type transition metal oxides for energy storage applications, therefore, nanostructural engineering is one of the most essential approaches to achieving high electrochemical performance in ESSs. In this perspective, we introduce spinel-type transition metal oxides with various transition metals and present recent research advances in material design of spinel-type transition metal oxides with tunable architectures (shape, porosity, and size) and compositions on the micro- and nano-scale. Furthermore, their technological applications as electrode materials for next-generation ESSs, including metal-air batteries, lithium-ion batteries, and supercapacitors, are discussed. PMID:26549729

  19. Making Sustainable Energy Choices: Insights on the Energy/Water/Land Nexus

    SciTech Connect

    Not Available

    2014-10-01

    This periodic publication summarizes insights from the body of NREL analysis work. In this issue of Analysis Insights, we examine the implications of our energy choices on water, land use, climate, developmental goals, and other factors. Collectively, NREL's work helps policymakers and investors understand and evaluate energy choices within the complex web of connections, or nexus, between energy, water, and land.

  20. Minimal cooling speed for glass transition in a simple solvable energy landscape model

    NASA Astrophysics Data System (ADS)

    Toledo-Marín, J. Quetzalcóatl; Castillo, Isaac Pérez; Naumis, Gerardo G.

    2016-06-01

    The minimal cooling speed required to form a glass is obtained for a simple solvable energy landscape model. The model, made from a two-level system modified to include the topology of the energy landscape, is able to capture either a glass transition or a crystallization depending on the cooling rate. In this setup, the minimal cooling speed to achieve glass formation is then found to be related with the crystallization relaxation time, energy barrier and with the thermal history. In particular, we obtain that the thermal history encodes small fluctuations around the equilibrium population which are exponentially amplified near the glass transition, which mathematically corresponds to the boundary layer of the master equation. The change in the glass transition temperature is also found as a function of the cooling rate. Finally, to verify our analytical results, a kinetic Monte Carlo simulation was implemented.

  1. Activation energy of the low-load NaCl transition from nanoindentation loading curves.

    PubMed

    Kaupp, Gerd

    2014-01-01

    Access to activation energies E(a) of phase transitions is opened by unprecedented analyses of temperature dependent nanoindentation loading curves. It is based on kinks in linearized loading curves, with additional support by coincidence of kink and electrical conductivity of silicon loading curves. Physical properties of B1, B2, NaCl and further phases are discussed. The normalized low-load transition energy of NaCl (Wtrans/µN) increases with temperature and slightly decreases with load. Its semi-logarithmic plot versus T obtains activation energy E(a)/µN for calculation of the transition work for all interesting temperatures and pressures. Arrhenius-type activation energy (kJ/mol) is unavailable for indentation phase transitions. The E(a) per load normalization proves insensitive to creep-on-load, which excludes normalization to depth or volume for large temperature ranges. Such phase transition E(a)/µN is unprecedented material's property and will be of practical importance for the compatibility of composite materials under impact and further shearing interactions at elevated temperatures.

  2. Energy and environmental policy in a period of transition

    SciTech Connect

    Stalon, C.G.

    1995-12-31

    This paper discusses governance aspects of electric industry restructuring. The creation and preservation of a governance system to ensure reliable and efficient trades within interconnected and independent trading areas is the main topic. The closely related issue of defining and imposing responsibilities on non-utility generators is also discussed in detail. It is recommended that the Federal Energy Regulatory Commission promote private governance of interconnections. 1 tab.

  3. State transitions redistribute rather than dissipate energy between the two photosystems in Chlamydomonas.

    PubMed

    Nawrocki, Wojciech J; Santabarbara, Stefano; Mosebach, Laura; Wollman, Francis-André; Rappaport, Fabrice

    2016-01-01

    Photosynthesis converts sunlight into biologically useful compounds, thus fuelling practically the entire biosphere. This process involves two photosystems acting in series powered by light harvesting complexes (LHCs) that dramatically increase the energy flux to the reaction centres. These complexes are the main targets of the regulatory processes that allow photosynthetic organisms to thrive across a broad range of light intensities. In microalgae, one mechanism for adjusting the flow of energy to the photosystems, state transitions, has a much larger amplitude than in terrestrial plants, whereas thermal dissipation of energy, the dominant regulatory mechanism in plants, only takes place after acclimation to high light. Here we show that, at variance with recent reports, microalgal state transitions do not dissipate light energy but redistribute it between the two photosystems, thereby allowing a well-balanced influx of excitation energy. PMID:27249564

  4. Pressure-Induced Structural Transition and Enhancement of Energy Gap of CuAlO2

    NASA Astrophysics Data System (ADS)

    Nakanishi, Akitaka

    2011-02-01

    By using first-principles calculations, we studied the stable crystal structures and energy gaps of CuAlO2 under high pressure. Our simulation shows that CuAlO2 transforms from a delafossite structure to a leaning delafossite structure. The critical pressure of the transition was determined to be 60 GPa. The energy gap of CuAlO2 increases through the structural transition due to the enhanced covalency of Cu 3d and O 2p states. We found that a chalcopyrite structure does not appear as a stable structure under high pressure.

  5. Energy levels and transition probabilities in doubly-ionized erbium (Er III).

    NASA Astrophysics Data System (ADS)

    Wyart, J.-F.; Blaise, J.; Bidelman, W. P.; Cowley, C. R.

    1997-11-01

    The spectrum of Er III reported by Becher (1966) was reanalysed with the support of new predictions of energies and transition probabilities. The number of energy levels was increased from 45 to 115, including two levels of 4f117s and the levels 3F3, 3F2 and 1G4 of the ground configuration 4f12. All 470 classified lines are reported with transition probabilities for most of them. Several of these lines had not yet been attributed to Er III in the spectrum of the star HR 465.

  6. Relativistic M-subshell radiationless transition probabilities and energies for Zn, Cd and Hg

    SciTech Connect

    Sampaio, J.M.; Parente, F.; Indelicato, P.; Marques, J.P.

    2014-09-15

    Theoretical calculations of radiationless transition probabilities and energies for M-subshell vacancies in Zn, Cd, and Hg are tabulated using the Dirac–Fock method. Transition probabilities between an initial vacancy state and a final two-vacancies state are presented for each initial and final atomic angular momentum quantum number. Calculations were performed in the single configuration approach with the Breit interaction, self-energy and (Uehling) vacuum polarization corrections included in the self-consistent method. Higher-order retardation corrections and QED effects were also included as perturbations.

  7. Astronomy in Sustainable Energy: A New Approach to Make It Matter

    NASA Astrophysics Data System (ADS)

    Ruzhitskaya, Lanika; Speck, A.

    2012-01-01

    We present a study of a new approach to teaching non-science students concepts of sustainable energy using astronomy, real life and fictional scenarios. Teaching non-science majors about energy is important because of the challenge that scientific (il)literacy poses for tangible and political problems like energy. We have established a course in which students are involved in critical thinking and the process of scientific reasoning while discovering the nature of energy and its role in our lives and its presentation in the fiction genre. In the course, students construct and apply their knowledge of transformation of energy to understanding of the concepts of the formation of the sun and the planets. Along with these concepts, students learn about ways of harnessing energy for sustaining life on Earth. During the course students transform their "Why do I care?” to "What can I do?” We are achieving this change by starting with a broad introduction of the concepts and physical laws involved in understanding of the Solar Nebular hypothesis during which we discuss the role of different forms of energy involved in the process. In the next step we narrow down the discussion to importance and use of energy on Earth and then we discuss the role of different forms of energy in maintaining our individual lives. Thus students go from intangible notions about energy to making informed decisions on what type of sustainable energy makes sense to use in their houses and how many burgers they want to eat per day. Moving towards sustainable energy technologies requires a public who understands the science behind the issues. The work presented here is aimed at providing a mechanism for increase literacy regarding these issues and testing this mechanism's success.

  8. Use of energy policy research and/or analysis in congressional decision making

    SciTech Connect

    Ahiarah, S.C.O.

    1985-01-01

    Regardless of what anyone thinks about it, policy science, as conceived by Lasswell, has become a discipline that is breeding new professionals who are producing policy researches and/or analyses decision making. But are they so used - is the intended marriage between PRA information and public policy decision making taking place. Many think they are, although others are skeptical. This study goes beyond the question of whether or not PRAs are used in public policy decision making, to investigate the purposes for which they are used therein. The public-policy decision making context selected is the legislative (congressional) decision making occasions in energy issues between 1979 and 1982; the objects of use are the energy PRAs from three congressional support agencies - the General Accounting Office, the Office of Technology Assessment, and the Congressional Budget Office. The findings are that when use is defined as congressional admission of the PRAs, all support agency PRAs are used, but when use is defined in terms of Congress Considering or adapting the PRAs in its decision making contexts, only a portion of all the support agency PRAs get used. The PRAs that are consideratively or adaptively used are more likely to be used for enlightenment, position support, and/or symbolic-propagandistic purposes.

  9. Learning from photosynthesis: how to use solar energy to make fuels.

    PubMed

    Cogdell, Richard J; Gardiner, Alastair T; Cronin, Leroy

    2012-08-13

    This short review describes how the basic reactions of photosynthesis can be broken down into four distinct steps. The current understanding of the molecular mechanisms of these steps, within light-harvesting complexes and reaction centres, in this process is discussed as a framework for the construction of artificial systems capable of using solar energy to make fuels.

  10. Modeling the Oil Transition: A Summary of the Proceedings of the DOE/EPA Workshop on the Economic and Environmental Implications of Global Energy Transitions

    SciTech Connect

    Greene, David L

    2007-02-01

    The global energy system faces sweeping changes in the next few decades, with potentially critical implications for the global economy and the global environment. It is important that global institutions have the tools necessary to predict, analyze and plan for such massive change. This report summarizes the proceedings of an international workshop concerning methods of forecasting, analyzing, and planning for global energy transitions and their economic and environmental consequences. A specific case, it focused on the transition from conventional to unconventional oil and other energy sources likely to result from a peak in non-OPEC and/or global production of conventional oil. Leading energy models from around the world in government, academia and the private sector met, reviewed the state-of-the-art of global energy modeling and evaluated its ability to analyze and predict large-scale energy transitions.

  11. Wind Power: A Renewable Energy Source for Mars Transit Vehicle

    NASA Technical Reports Server (NTRS)

    Flynn, Michael; Kohout, Lisa; Kliss, Mark (Technical Monitor)

    1998-01-01

    The Martian environment presents significant design challenges for the development of power generation systems. Nuclear-based systems may not be available due to political and safety concerns. The output of photovoltaics are limited by a solar intensity of 580 W/sqm as compared to 1353 W/sqm on Earth. The presence of dust particles in the Mars atmosphere will further reduce the photovoltaic output. Also, energy storage for a 12-hour night period must be provided. In this challenging environment, wind power generation capabilities may provide a viable option as a Martian power generation system. This paper provides an analysis of the feasibility of such a system.

  12. Thinking Globally: How ISO 50001 - Energy Management can make industrial energy efficiency standard practice

    SciTech Connect

    McKane, Aimee; Desai, Deann; Matteini, Marco; Meffert, William; Williams, Robert; Risser, Roland

    2009-08-01

    Industry utilizes very complex systems, consisting of equipment and their human interface, which are organized to meet the production needs of the business. Effective and sustainable energy efficiency programs in an industrial setting require a systems approach to optimize the integrated whole while meeting primary business requirements. Companies that treat energy as a manageable resource and integrate their energy program into their management practices have an organizational context to continually seek opportunities for optimizing their energy use. The purpose of an energy management system standard is to provide guidance for industrial and commercial facilities to integrate energy efficiency into their management practices, including fine-tuning production processes and improving the energy efficiency of industrial systems. The International Organization for Standardization (ISO) has identified energy management as one of its top five priorities for standards development. The new ISO 50001 will establish an international framework for industrial, commercial, or institutional facilities, or entire companies, to manage their energy, including procurement and use. This standard is expected to achieve major, long-term increases in energy efficiency (20percent or more) in industrial, commercial, and institutional facilities and to reduce greenhouse gas (GHG) emissions worldwide.This paper describes the impetus for the international standard, its purpose, scope and significance, and development progress to date. A comparative overview of existing energy management standards is provided, as well as a discussion of capacity-building needs for skilled individuals to assist organizations in adopting the standard. Finally, opportunities and challenges are presented for implementing ISO 50001 in emerging economies and developing countries.

  13. CEOS Contributions to Informing Energy Management and Policy Decision Making Using Space-Based Earth Observations

    NASA Technical Reports Server (NTRS)

    Eckman, Richard S.

    2009-01-01

    Earth observations are playing an increasingly significant role in informing decision making in the energy sector. In renewable energy applications, space-based observations now routinely augment sparse ground-based observations used as input for renewable energy resource assessment applications. As one of the nine Group on Earth Observations (GEO) societal benefit areas, the enhancement of management and policy decision making in the energy sector is receiving attention in activities conducted by the Committee on Earth Observation Satellites (CEOS). CEOS has become the "space arm" for the implementation of the Global Earth Observation System of Systems (GEOSS) vision. It is directly supporting the space-based, near-term tasks articulated in the GEO three-year work plan. This paper describes a coordinated program of demonstration projects conducted by CEOS member agencies and partners to utilize Earth observations to enhance energy management end-user decision support systems. I discuss the importance of engagement with stakeholders and understanding their decision support needs in successfully increasing the uptake of Earth observation products for societal benefit. Several case studies are presented, demonstrating the importance of providing data sets in formats and units familiar and immediately usable by decision makers. These projects show the utility of Earth observations to enhance renewable energy resource assessment in the developing world, forecast space-weather impacts on the power grid, and improve energy efficiency in the built environment.

  14. Spectroscopic elucidation of uncoupled transition energies in the major photosynthetic light-harvesting complex, LHCII

    PubMed Central

    Schlau-Cohen, Gabriela S.; Calhoun, Tessa R.; Ginsberg, Naomi S.; Ballottari, Matteo; Bassi, Roberto; Fleming, Graham R.

    2010-01-01

    Electrostatic couplings between chromophores in photosynthetic pigment–protein complexes, and interactions of pigments with the surrounding protein environment, produce a complicated energy landscape of delocalized excited states. The resultant electronic structure absorbs light and gives rise to energy transfer steps that direct the excitation toward a site of charge separation with near unity quantum efficiency. Knowledge of the transition energies of the uncoupled chromophores is required to describe how the wave functions of the individual pigments combine to form this manifold of delocalized excited states that effectively harvests light energy. In an investigation of the major light-harvesting complex of photosystem II (LHCII), we develop a method based on polarized 2D electronic spectroscopy to experimentally access the energies of the S0–S1 transitions in the chromophore site basis. Rotating the linear polarization of the incident laser pulses reveals previously hidden off-diagonal features. We exploit the polarization dependence of energy transfer peaks to find the angles between the excited state transition dipole moments. We show that these angles provide a spectroscopic method to directly inform on the relationship between the delocalized excitons and the individual chlorophylls through the site energies of the uncoupled chromophores. PMID:20622154

  15. Precise Determination of the Lyman-1 Transition Energy in Hydrogen-like Gold Ions with Microcalorimeters

    NASA Astrophysics Data System (ADS)

    Kraft-Bermuth, S.; Andrianov, V.; Bleile, A.; Echler, A.; Egelhof, P.; Grabitz, P.; Kilbourne, C.; Kiselev, O.; McCammon, D.; Scholz, P.

    2014-09-01

    The precise determination of the transition energy of the Lyman-1 line in hydrogen-like heavy ions provides a sensitive test of quantum electrodynamics in very strong Coulomb fields. We report the determination of the Lyman-1 transition energy of gold ions (Au) with microcalorimeters at the experimental storage ring at GSI. X-rays produced by the interaction of 125 MeV/u Au ions with an internal argon gas-jet target were detected. The detector array consisted of 14 pixels with silicon thermistors and Sn absorbers, for which an energy resolution of 50 eV for an X-ray energy of 59.5 keV was obtained in the laboratory. The Lyman-1 transition energy was determined for each pixel in the laboratory frame, then transformed into the emitter frame and averaged. A Dy-159 source was used for energy calibration. The absolute positions of the detector pixels, which are needed for an accurate correction of the Doppler shift, were determined by topographic measurements and by scanning a collimated Am-241 source across the cryostat window. The energy of the Lyman-1 line in the emitter frame is eV, in good agreement with theoretical predictions. The systematic error is dominated by the uncertainty in the position of the cryostat relative to the interaction region of beam and target.

  16. Large conversion of energy in dielectric elastomers by electromechanical phase transition

    NASA Astrophysics Data System (ADS)

    Lu, Tong-Qing; Suo, Zhi-Gang

    2012-08-01

    When air is pumped in, a tubular balloon initially inflates slightly and homogeneously. A short section of the balloon then forms a bulge, which coexists with the unbulged section of the balloon. As more air is pumped in, the bulged section elongates at the expense of the unbulged section, until the entire balloon is bulged. The phenomenon is analogous to the liquid-to-vapor phase transition. Here we study the bulging transition in a dielectric elastomer tube as air is pumped into the balloon and a voltage is applied through the thickness of the membrane. We formulate the condition for coexistent budged and unbulged sections, and identify allowable states set by electrical breakdown and mechanical rupture. We find that the bulging transition dramatically amplifies electromechanical energy conversion. Energy converted in an electromechanical cycle consisting of unbulged and bulged states is thousands of times that in an electromechanical cycle consisting of only unbulged states.

  17. STABILITY IN BCC TRANSITION METALS: MADELUNG AND BAND-ENERGY EFFECTS DUE TO ALLOYING

    SciTech Connect

    Landa, A; Soderlind, P; Ruban, A; Peil, O; Vitos, L

    2009-08-28

    The phase stability of the bcc Group VB (V, Nb, and Ta) transition metals is explored by first-principles electronic-structure calculations. Alloying with a small amount of a neighboring metal can either stabilize or destabilize the bcc phase. This counterintuitive behavior is explained by competing mechanisms that dominate depending on particular dopand. We show that band-structure effects dictate stability when a particular Group VB metal is alloyed with its nearest neighbors within the same d-transition series. In this case, the neighbor with less (to the left) and more (to the right) d electrons, destabilize and stabilize bcc, respectively. When alloying with neighbors of different d-transition series, electrostatic Madelung energy dominates over the band energy and always stabilizes the bcc phase.

  18. A transition radiation detector prototype to measure the energy of muons in cosmic ray laboratories

    NASA Astrophysics Data System (ADS)

    Bellotti, R.; Cafagna, F.; Calicchio, M.; Castellano, M.; De Cataldo, G.; De Marzo, C.; Enriquez, O.; Favuzzi, C.; Fusco, P.; Giglietto, N.; Mongelli, M.; Nappi, E.; Perchiazzi, M.; Sacchetti, A.; Spinelli, P.

    1991-07-01

    We have developed and tested a transition radiation detector prototype suitable to measure the energy of muons in cosmic ray laboratories. The technical solutions adopted, based on extruded tubes as detectors and foam or fiber mats as radiators, allow to cover very large areas with a low number of channels and ensure stability of operation. Using an argon-carbon dioxide gas mixture it is possible to explore the muon energy range up to 1 TeV.

  19. Energy transfer enhancement by oxygen perturbation of spin-forbidden electronic transitions in aromatic systems

    NASA Astrophysics Data System (ADS)

    Monguzzi, A.; Tubino, R.; Salamone, M. M.; Meinardi, F.

    2010-09-01

    Triplet-triplet energy transfer in multicomponent organic systems is usually entirely ascribed to a Dexter-type mechanism involving only short-range donor/acceptor interactions. We demonstrate that the presence of molecular oxygen introduces a perturbation to the electronic structure of one of the involved moieties which can induce a large increase in the spin-forbidden transition oscillator strength so that the otherwise negligible Förster contribution dominates the overall energy transfer rate.

  20. Surface energy from order parameter profile: At the QCD phase transition

    NASA Technical Reports Server (NTRS)

    Frei, Z.; Patkos, A.

    1989-01-01

    The order parameter profile between coexisting confined and plasma regions at the quantum chromodynamic (QCD) phase transition is constructed. The dimensionless combination of the surface energy (Sigma) and the correlation length (Zeta) is estimated to be Sigma Zeta 3 approximately equals 0.8.

  1. Relevance of behavioral and social models to the study of consumer energy decision making and behavior

    SciTech Connect

    Burns, B.A.

    1980-11-01

    This report reviews social and behavioral science models and techniques for their possible use in understanding and predicting consumer energy decision making and behaviors. A number of models and techniques have been developed that address different aspects of the decision process, use different theoretical bases and approaches, and have been aimed at different audiences. Three major areas of discussion were selected: (1) models of adaptation to social change, (2) decision making and choice, and (3) diffusion of innovation. Within these three areas, the contributions of psychologists, sociologists, economists, marketing researchers, and others were reviewed. Five primary components of the models were identified and compared. The components are: (1) situational characteristics, (2) product characteristics, (3) individual characteristics, (4) social influences, and (5) the interaction or decision rules. The explicit use of behavioral and social science models in energy decision-making and behavior studies has been limited. Examples are given of a small number of energy studies which applied and tested existing models in studying the adoption of energy conservation behaviors and technologies, and solar technology.

  2. Determination of electron bunch shape using transition radiation and phase-energy measurements

    SciTech Connect

    Crosson, E.R.; Berryman, K.W.; Richman, B.A.

    1995-12-31

    We present data comparing microbunch temporal information obtained from electron beam phase-energy measurements with that obtained from transition radiation auto-correlation measurements. The data was taken to resolve some of the ambiguities in previous transition radiation results. By measuring the energy spectrum of the electron beam as a function of its phase relative to the accelerating field, phase-energy information was extracted. This data was analyzed using tomographic techniques to reconstruct the phase-space distribution assuming an electron energy dependence of E({var_phi}) = E{sub o} + E{sub acc}cos({var_phi}), where E{sub o} is the energy of an electron entering the field, E{sub acc} is the peak energy gain, and {var_phi} is the phase between the crest of the RF wave and an electron. Temporal information about the beam was obtained from the phase space distribution by taking the one dimensional projection along the time axis. We discuss the use of this technique to verify other transition radiation analysis methods.

  3. Statistical simulation of internal energy exchange in shock waves using explicit transition probabilities

    NASA Astrophysics Data System (ADS)

    Torres, Erik; Magin, Thierry

    2012-11-01

    A statistical model originally developed for electronic-translational energy transfer in atoms having multiple electronic states (Anderson et al, RGD15, 1986) is applied to the study of internal energy exchange in a polyatomic gas. The model is well-suited for gas kinetic simulations, because it provides an explicit expression for the transition probabilities between internal energy levels. All molecules possessing a given internal energy level are treated as a separate chemical species and all collisions involving exchange of internal energy thus become pseudo-chemical reactions. Post-collision energy levels of the two partners are determined by conserving the total energy of the collision pair and taking into account detailed balance. In the present work, DSMC simulations of relaxation in a stationary gas are performed and compared to those obtained by Anderson et al. Additionally, we apply the model to the simulation of rotational relaxation behind a normal shock wave.

  4. Transition from a matter-dominated era to a dark energy universe

    SciTech Connect

    Nojiri, Shin'ichi; Odintsov, Sergei D.; Stefancic, Hrvoje

    2006-10-15

    We develop a general program of the unification of a matter-dominated era with an acceleration epoch for scalar-tensor theory or a dark fluid. The general reconstruction of the scalar-tensor theory is fulfilled. The explicit form of the scalar potential for which the theory admits a matter-dominated era, a transition to an acceleration, and an (asymptotically de Sitter) acceleration epoch consistent with Wilkinson Microwave Anisotropy Probe data is found. The interrelation of the epochs of deceleration-acceleration transition and matter dominance-dark energy transition for dark fluids with a general equation of state (EOS) is investigated. We give several examples of such models with explicit EOS (using redshift parametrization) where matter-dark energy domination transition may precede the deceleration-acceleration transition. As a by-product, the reconstruction scheme is applied to scalar-tensor theory to define the scalar potentials which may produce the dark matter effect. The obtained modification of Newton potential may explain the rotation curves of galaxies.

  5. Career Decision Making for Male Students with Attention Deficit Hyperactivity Disorder: A Model of Critical Factors Aiding in Transitional Efforts

    ERIC Educational Resources Information Center

    Gray, Gregory B.

    2009-01-01

    This study is intended to reveal helpful information that will guide high school practitioners in serving students with attention deficit hyperactivity disorder (ADHD) more effectively. ADHD is neurological in origin, making it invisible. This disorder makes people susceptible to distractibility, impulsivity, disorganization, frustration, anxiety,…

  6. Sexual Communication, Sexual Goals, and Students' Transition to College: Implications for Sexual Assault, Decision-Making, and Risky Behaviors

    ERIC Educational Resources Information Center

    Lindgren, Kristen P.; Schacht, Rebecca L.; Pantalone, David W.; Blayney, Jessica A.; George, William H.

    2009-01-01

    A qualitative study was conducted to understand college students' experiences and perceptions of sexual communication and sexual goals, and how they were affected by the transition from high school to college. Participants were heterosexual college students (N = 29). Single-sex focus groups were conducted and analyzed for themes. Major themes…

  7. Helping Low-Income Urban Youth Make the Transition to Early Adulthood: A Retrospective Study of the YMCA Youth Institute

    ERIC Educational Resources Information Center

    O'Donnell, Julie; Kirkner, Sandra L.

    2016-01-01

    Low-income urban youth of color often face challenges in their transition to early adulthood. High school out-of-school time (OST) programs that promote positive youth development may help youth to better negotiate this period. However, little research exists on the long-term impact of such programs on young adults. The authors conducted a pilot…

  8. What Can Be Learned from the Roller Coaster Journeys of Young People Making Ultimately Successful Transitions beyond School?

    ERIC Educational Resources Information Center

    Bryce, Jennifer; Anderson, Michelle

    2008-01-01

    This project investigated the interrelationships between family expectations and young people's post-school plans. All of the participants were from financially disadvantaged families. The research used interviews to understand these young people's perspectives of their transition experiences: the ways in which young people's school experiences…

  9. Seamless Transitions: Collaborations That Benefit Children and Their Families Making the Move from Preschool to Early Elementary.

    ERIC Educational Resources Information Center

    Velazquez, Sheila Roman, Ed.

    This report summarizes the proceedings of two clinics on early childhood clinics and provides descriptions of successful preschool-to-elementary transition programs. The two clinics brought together Head Start representatives, public and private day care personnel, elementary school teachers and administrators, state department of education staff,…

  10. Helping Children on the Autism Spectrum Make a Successful Transition from Middle School to High School and Beyond

    ERIC Educational Resources Information Center

    Connell, Diane; Hutnick, Marilyn; Glover, Sandi; Glover, Curtis

    2012-01-01

    Transitioning from middle school to high school is a tremendous change for all students; it is especially important for learners on the Autism Spectrum. In this article, the authors discuss the move to high school and give seven tips for successfully navigating these years. We draw upon the experiences of Mrs. Sandi Glover and her 21-year-old son…

  11. Calculating Transition Energy Barriers and Characterizing Activation States for Steps of Fusion.

    PubMed

    Ryham, Rolf J; Klotz, Thomas S; Yao, Lihan; Cohen, Fredric S

    2016-03-01

    We use continuum mechanics to calculate an entire least energy pathway of membrane fusion, from stalk formation, to pore creation, and through fusion pore enlargement. The model assumes that each structure in the pathway is axially symmetric. The static continuum stalk structure agrees quantitatively with experimental stalk architecture. Calculations show that in a stalk, the distal monolayer is stretched and the stored stretching energy is significantly less than the tilt energy of an unstretched distal monolayer. The string method is used to determine the energy of the transition barriers that separate intermediate states and the dynamics of two bilayers as they pass through them. Hemifusion requires a small amount of energy independently of lipid composition, while direct transition from a stalk to a fusion pore without a hemifusion intermediate is highly improbable. Hemifusion diaphragm expansion is spontaneous for distal monolayers containing at least two lipid components, given sufficiently negative diaphragm spontaneous curvature. Conversely, diaphragms formed from single-component distal monolayers do not expand without the continual injection of energy. We identify a diaphragm radius, below which central pore expansion is spontaneous. For larger diaphragms, prior studies have shown that pore expansion is not axisymmetric, and here our calculations supply an upper bound for the energy of the barrier against pore formation. The major energy-requiring deformations in the steps of fusion are: widening of a hydrophobic fissure in bilayers for stalk formation, splay within the expanding hemifusion diaphragm, and fissure widening initiating pore formation in a hemifusion diaphragm.

  12. Activation energy for a model ferrous-ferric half reaction from transition path sampling

    NASA Astrophysics Data System (ADS)

    Drechsel-Grau, Christof; Sprik, Michiel

    2012-01-01

    Activation parameters for the model oxidation half reaction of the classical aqueous ferrous ion are compared for different molecular simulation techniques. In particular, activation free energies are obtained from umbrella integration and Marcus theory based thermodynamic integration, which rely on the diabatic gap as the reaction coordinate. The latter method also assumes linear response, and both methods obtain the activation entropy and the activation energy from the temperature dependence of the activation free energy. In contrast, transition path sampling does not require knowledge of the reaction coordinate and directly yields the activation energy [C. Dellago and P. G. Bolhuis, Mol. Simul. 30, 795 (2004), 10.1080/08927020412331294869]. Benchmark activation energies from transition path sampling agree within statistical uncertainty with activation energies obtained from standard techniques requiring knowledge of the reaction coordinate. In addition, it is found that the activation energy for this model system is significantly smaller than the activation free energy for the Marcus model, approximately half the value, implying an equally large entropy contribution.

  13. Calculating Transition Energy Barriers and Characterizing Activation States for Steps of Fusion.

    PubMed

    Ryham, Rolf J; Klotz, Thomas S; Yao, Lihan; Cohen, Fredric S

    2016-03-01

    We use continuum mechanics to calculate an entire least energy pathway of membrane fusion, from stalk formation, to pore creation, and through fusion pore enlargement. The model assumes that each structure in the pathway is axially symmetric. The static continuum stalk structure agrees quantitatively with experimental stalk architecture. Calculations show that in a stalk, the distal monolayer is stretched and the stored stretching energy is significantly less than the tilt energy of an unstretched distal monolayer. The string method is used to determine the energy of the transition barriers that separate intermediate states and the dynamics of two bilayers as they pass through them. Hemifusion requires a small amount of energy independently of lipid composition, while direct transition from a stalk to a fusion pore without a hemifusion intermediate is highly improbable. Hemifusion diaphragm expansion is spontaneous for distal monolayers containing at least two lipid components, given sufficiently negative diaphragm spontaneous curvature. Conversely, diaphragms formed from single-component distal monolayers do not expand without the continual injection of energy. We identify a diaphragm radius, below which central pore expansion is spontaneous. For larger diaphragms, prior studies have shown that pore expansion is not axisymmetric, and here our calculations supply an upper bound for the energy of the barrier against pore formation. The major energy-requiring deformations in the steps of fusion are: widening of a hydrophobic fissure in bilayers for stalk formation, splay within the expanding hemifusion diaphragm, and fissure widening initiating pore formation in a hemifusion diaphragm. PMID:26958888

  14. Energy levels, radiative rates, and lifetimes for transitions in W LVIII

    SciTech Connect

    Aggarwal, Kanti M. Keenan, Francis P.

    2014-11-15

    Energy levels and radiative rates are reported for transitions in Cl-like W LVIII. Configuration interaction (CI) has been included among 44 configurations (generating 4978 levels) over a wide energy range up to 363 Ryd, and the general-purpose relativistic atomic structure package (GRASP) adopted for the calculations. Since no other results of comparable complexity are available, calculations have also been performed with the flexible atomic code (FAC), which help in assessing the accuracy of our results. Energies are listed for the lowest 400 levels (with energies up to ∼98 Ryd), which mainly belong to the 3s{sup 2}3p{sup 5}, 3s3p{sup 6}, 3s{sup 2}3p{sup 4}3d, 3s{sup 2}3p{sup 3}3d{sup 2}, 3s3p{sup 4}3d{sup 2}, 3s{sup 2}3p{sup 2}3d{sup 3}, and 3p{sup 6}3d configurations, and radiative rates are provided for four types of transitions, i.e. E1, E2, M1, and M2. Our energy levels are assessed to be accurate to better than 0.5%, whereas radiative rates (and lifetimes) should be accurate to better than 20% for a majority of the strong transitions.

  15. Calculation of Zeeman splitting and Zeeman transition energies of spherical quantum dot in uniform magnetic field

    NASA Astrophysics Data System (ADS)

    Çakır, Bekir; Atav, Ülfet; Yakar, Yusuf; Özmen, Ayhan

    2016-08-01

    In this study we report a detailed theoretical investigation of the effect of an external magnetic field on the 1s-, 2p-, 3d- and 4f-energy states of a spherical quantum dot. We treat the contribution of the diamagnetic term as a perturbation and discuss the effect of the diamagnetic term on the 1s-, 2p-, 3d- and 4f-energy states. We also have calculated the Zeeman transition energies between 2p → 1s and 3d → 2p states with m = 0, ±1 and 0, ±1, ±2 as a function of dot radius and the magnetic field strength. The results show that the magnetic field, impurity charge and dot radius have a strong influence on the energy states and the Zeeman transitions. It is found that the energies of the electronic states with m < 0 addition of the diamagnetic term firstly decrease toward a minimum, and then increase with the increasing magnetic field strength. We have seen that as magnetic field intensity is adjusted, frequency of the emitted light can be changed for Zeeman transitions.

  16. Measurements of the spectrum and energy dependence of X-ray transition radiation

    NASA Technical Reports Server (NTRS)

    Cherry, M. L.

    1978-01-01

    The results of experiments designed to test the theory of X-ray transition radiation and to verify the predicted dependence of the characteristic features of the radiation on the radiator dimensions are presented. The X-ray frequency spectrum produced by 5- to 9-GeV electrons over the range 4 to 30 keV was measured with a calibrated single-crystal Bragg spectrometer, and at frequencies up to 100 keV with an NaI scintillator. The interference pattern in the spectrum and the hardening of the radiation with increasing foil thickness are clearly observed. The energy dependence of the total transition-radiation intensity was studied using a radiator with large dimensions designed to yield energy-dependent signals at very high particle energies, up to E/mc-squared approximately equal to 100,000. The results are in good agreement with the theoretical predictions.

  17. Unnotched Charpy Impact Energy Transition Behavior of Austempered Engineering Grade Ductile Iron Castings

    NASA Astrophysics Data System (ADS)

    Kisakurek, Sukru Ergin; Ozel, Ahmet

    2014-04-01

    Unnotched Charpy impact energy transition behavior of five different engineering grade ductile iron castings, as specified by EN 1563 Standards, were examined in as-cast, as well as in austempered states. ADIs were produced with the maximum impact energy values permissible for the grades. Austempering treatment detrimented the sub-zero impact properties of the ferritic castings, but considerably enhanced those of the pearlitic-ferritic irons. The impact energy transition behavior of the austempered states of all the grades examined were noted to be determined by the progressive transformation of the unavoidable carbon-unsaturated and untransformed regions of the austenite remaining in the matrix of the austempered ductile iron to martensite with decreasing temperature.

  18. Development regulation changes local elected leaders can make to promote energy conservation

    SciTech Connect

    Kron, Jr, N F

    1980-07-01

    This report lists actions that local officials can make to change their community's development regulations and thereby lessen the effects of local energy problems. The term development regulations, as used here, is a general reference to local or state controls over land use and development that affect design, orientation, placement, location, and related characteristics of buildings and infrastructure. The regulations include items such as zoning, subdivision controls, setbacks, yard and height requirements, and solar-access ordinances.

  19. Energies and Electric Dipole Transitions for Low-Lying Levels of Protactinium IV and Uranium V

    NASA Astrophysics Data System (ADS)

    Ürer, Güldem; Özdemir, Leyla

    2012-02-01

    We have reported a relativistic multiconfiguration Dirac-Fock (MCDF) study on low-lying level structures of protactinium IV (Z =91) and uranium V (Z =92) ions. Excitation energies and electric dipole (E1) transition parameters (wavelengths, oscillator strengths, and transition rates) for these low-lying levels have been given. We have also investigated the influence of the transverse Breit and quantum electrodynamic (QED) contributions besides correlation effects on the level structure. A comparison has been made with a few available data for these ions in the literature.

  20. Inverse correlation between cohesive energy and thermal expansion coefficient in liquid transition metal alloys.

    PubMed

    Gangopadhyay, A K; Bendert, J C; Mauro, N A; Kelton, K F

    2012-09-19

    The volume expansion coefficients (α) of twenty-five glass-forming transition metal alloy liquids, measured using the electrostatic levitation technique, are reported. An inverse correlation between α and the cohesive energy is found. The predicted values of α from this relationship agree reasonably well with the published data for thirty other transition metal and alloy liquids; some disagreement was found for a few alloys containing significant amounts of group III and IV elements. A theoretical argument for this empirical relationship is presented. PMID:22842287

  1. Energies, Wavelengths, and Transition Rates for Ga-Like Ions (Nd XXX-Tb XXXV)

    NASA Astrophysics Data System (ADS)

    El-Sayed, Fatma; Attia, S. M.

    2016-03-01

    Energies, wavelengths, transition probabilities, oscillator strengths, and line strengths have been calculated for 4s24p-4s4p2 and 4s24p-4s24d transitions in gallium-like ions from Z = 60 to 65, for Nd XXX, Pm XXXI, Sm XXXII, Eu XXXIII, Gd XXXIV, and Tb XXXV using the fully relativistic multiconfi guration Dirac-Fock method. The correlation with the n = 4 complex and the quantum electrodynamic effects have been considered in the calculations. The obtained results have been compared with the available experimental and other theoretical results.

  2. Improving energy efficiency: Strategies for supporting sustained market evolution in developing and transitioning countries

    SciTech Connect

    Meyers, S.

    1998-02-01

    This report presents a framework for considering market-oriented strategies for improving energy efficiency that recognize the conditions of developing and transitioning countries, and the need to strengthen the effectiveness of market forces in delivering greater energy efficiency. It discusses policies that build markets in general, such as economic and energy pricing reforms that encourage competition and increase incentives for market actors to improve the efficiency of their energy use, and measures that reduce the barriers to energy efficiency in specific markets such that improvement evolves in a dynamic, lasting manner. The report emphasizes how different policies and measures support one another and can create a synergy in which the whole is greater than the sum of the parts. In addressing this topic, it draws on the experience with market transformation energy efficiency programs in the US and other industrialized countries.

  3. Monte Carlo method for determining free-energy differences and transition state theory rate constants

    SciTech Connect

    Voter, A.F.

    1985-02-15

    We present a new Monte Carlo procedure for determining the Helmholtz free-energy difference between two systems that are separated in configuration space. Unlike most standard approaches, no integration over intermediate potentials is required. A Metropolis walk is performed for each system, and the average Metropolis acceptance probability for a hypothetical step along a probe vector into the other system is accumulated. Either classical or quantum free energies may be computed, and the procedure is also ideally suited for evaluating generalized transition state theory rate constants. As an application we determine the relative free energies of three configurations of a tungsten dimer on the W(110) surface.

  4. Scaling Properties of Adsorption Energies for Hydrogen-Containing Molecules on Transition-Metal Surfaces

    NASA Astrophysics Data System (ADS)

    Abild-Pedersen, F.; Greeley, J.; Studt, F.; Rossmeisl, J.; Munter, T. R.; Moses, P. G.; Skúlason, E.; Bligaard, T.; Nørskov, J. K.

    2007-07-01

    Density functional theory calculations are presented for CHx, x=0,1,2,3, NHx, x=0,1,2, OHx, x=0,1, and SHx, x=0,1 adsorption on a range of close-packed and stepped transition-metal surfaces. We find that the adsorption energy of any of the molecules considered scales approximately with the adsorption energy of the central, C, N, O, or S atom, the scaling constant depending only on x. A model is proposed to understand this behavior. The scaling model is developed into a general framework for estimating the reaction energies for hydrogenation and dehydrogenation reactions.

  5. Specific Energy as an Index to Identify the Critical Failure Mode Transition Depth in Rock Cutting

    NASA Astrophysics Data System (ADS)

    He, Xianqun; Xu, Chaoshui

    2016-04-01

    Rock cutting typically involves driving a rigid cutter across the rock surface at certain depth of cut and is used to remove rock material in various engineering applications. It has been established that there exist two distinct failure modes in rock cutting, i.e. ductile mode and brittle mode. The ductile mode takes precedence when the cut is shallow and the increase in the depth of cut leads to rock failure gradually shifted to brittle-dominant mode. The threshold depth or the critical transition depth, at which rock failure under cutting changes from the ductile to the brittle mode, is associated with not only the rock properties but also the cutting operational parameters and the understanding of this threshold is important to optimise the tool design and operational parameters. In this study, a new method termed the specific cutting energy transition model is proposed from an energy perspective which is demonstrated to be much more effective in identifying the critical transition depth compared with existing approaches. In the ductile failure cutting mode, the specific cutting energy is found to be independent of the depth of cut; but in the brittle failure cutting mode, the specific cutting energy is found to be dependent on the depth of cut following a power-law relationship. The critical transition depth is identified as the intersection point between these two relationships. Experimental tests on two types of rocks with different combinations of cutting velocity, depth of cut and back rake angle are conducted and the application of the proposed model on these cutting datasets has demonstrated that the model can provide a very effective tool to analyse the cutting mechanism and to identify the critical transition depth.

  6. Energy star product specification development framework: Using data and analysis to make program decisions

    SciTech Connect

    McWhinney, Marla; Fanara, Andrew; Clark, Robin; Hershberg, Craig; Schmeltz, Rachel; Roberson, Judy

    2003-09-12

    The Product Development Team (PD) in the US Environmental Protection Agency's ENERGY STAR Labeling Program fuels the long-term market transformation process by delivering new specifications. PD's goal is to expand the reach and visibility of ENERGY STAR as well as the market for new energy-efficient products. Since 2000, PD has launched nine new ENERGY STAR specifications and continues to evaluate new program opportunities. To evaluate the ENERGY STAR carbon savings potential for a diverse group of products, PD prepared a framework for developing new and updating existing specifications that rationalizes new product opportunities and draws upon the expertise and resources of other stakeholders, including manufacturers, utilities, environmental groups and other government agencies. By systematically reviewing the potential of proposed product areas, PD makes informed decisions as to whether or not to proceed with developing a specification. In support of this strategy, PD ensures that new product specifications are consistent with the ENERGY STAR guidelines and that these guidelines are effectively communicated to stakeholders during the product development process. To date, the framework has been successful in providing consistent guidance on collecting the necessary information on which to base sound program decisions. Through the application of this framework, PD increasingly recognizes that each industry has unique market and product characteristics that can require reconciliation with the ENERGY STAR guidelines. The new framework allows PD to identify where reconciliation is needed to justify program decisions.

  7. Transition through co-optation: Harnessing carbon democracy for clean energy

    NASA Astrophysics Data System (ADS)

    Meng, Kathryn-Louise

    This dissertation explores barriers to a clean energy transition in the United States. Clean energy is demonstrably viable, yet the pace of clean energy adoption in the U.S. is slow, particularly given the immediate threat of global climate change. The purpose of this dissertation is to examine the factors inhibiting a domestic energy transition and to propose pragmatic approaches to catalyzing a transition. The first article examines the current political-economic and socio-technical energy landscape in the U.S. Fossil fuels are central to the functioning of the American economy. Given this centrality, constellations of power have been constructed around the reliable and affordable access of fossil fuels. The fossil fuel energy regime is comprised of: political-economic networks with vested interests in continued fossil fuel reliance, and fixed infrastructure that is minimally compatible with distributed generation. A transition to clean energy threatens the profitability of fossil fuel regime actors. Harnessing structural critiques from political ecology and process and function-oriented socio-technical systems frameworks, I present a multi-level approach to identifying pragmatic means to catalyzing an energy transition. High-level solutions confront the existing structure, mid-level solutions harness synergy with the existing structure, and low-level solutions lie outside of the energy system or foster the TIS. This is exemplified using a case study of solar development in Massachusetts. Article two presents a case study of the clean energy technological innovation system (TIS) in Massachusetts. I examine the actors and institutions that support cleantech development. Further, I scrutinize the actors and institutions that help sustain the TIS support system. The concept of a catalyst is presented; a catalyst is an actor that serves to propel TIS functions. Catalysts are critical to facilitating anchoring. Strategic corporate partners are identified as powerful

  8. Energies, wavelengths, and multipole transition probabilities for B-like Fe and Ga ions

    SciTech Connect

    El-Sayed, Fatma

    2013-09-15

    Energy levels, transition probabilities, oscillator strengths, line strengths, and lifetimes have been calculated for transitions in B-like Fe and Ga ions. The configurations 2s{sup 2}2p, 2s2p{sup 2}, 2p{sup 3}, 2s2p3ℓ, and 2p{sup 2}3ℓ were used in the calculations and 125 fine-structure levels were obtained. The fully relativistic GRASP code has been adopted, and results are reported for all electric dipole, electric quadrupole, magnetic dipole, and magnetic quadrupole transitions among the lowest 125 levels of Fe XXII and Ga XXVII, belonging to the n≤3 configurations. Comparisons are made with earlier available theoretical results.

  9. Energy Transition Initiative: Island Energy Snapshot - Belize; U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-03-01

    This profile provides a snapshot of the energy landscape of Belize, a Central American country bordering Mexico to the north, Guatemala to the west and south, and the Caribbean Sea to the east. Although not an island nation, Belize is included in this energy snapshot series because it is a member of the Caribbean Community (CARICOM), an alliance of 15 Caribbean nations in the region.

  10. Energies of Maxima and Oscillator Strengths of CaO Elementary Transition Bands Over a Wide Energy Range

    NASA Astrophysics Data System (ADS)

    Sobolev, V. V.; Merzlyakov, D. A.; Sobolev, V. Val.

    2016-09-01

    Integral spectra of the imaginary parts of the dielectric permittivity ɛ2(E) and characteristic volume (-Im ɛ-1) and surface [-Im (1 + ɛ)-1] energy losses of calcium oxide were deconvoluted into elementary components in the range 6-40 eV. The main component parameters including the energies of maxima and oscillator strengths were determined using an improved non-parametric method of united Argand diagrams and the method of the effective number of valence electrons participating in the transitions. A total of 41 components with oscillator strengths in the range 0.001-0.22 were identified instead of the 14 maxima and shoulders of the integral spectra. They were caused by transverse and longitudinal exciton and interband transitions.

  11. The sower’s way: quantifying the narrowing net-energy pathways to a global energy transition

    NASA Astrophysics Data System (ADS)

    Sgouridis, Sgouris; Csala, Denes; Bardi, Ugo

    2016-09-01

    Planning the appropriate renewable energy (RE) installation rate should balance two partially contradictory objectives: substituting fossil fuels fast enough to stave-off the worst consequences of climate change while maintaining a sufficient net energy flow to support the world’s economy. The upfront energy invested in constructing a RE infrastructure subtracts from the net energy available for societal energy needs, a fact typically neglected in energy projections. Modeling feasible energy transition pathways to provide different net energy levels we find that they are critically dependent on the fossil fuel emissions cap and phase-out profile and on the characteristic energy return on energy invested of the RE technologies. The easiest pathway requires installation of RE plants to accelerate from 0.12 TWp yr–1 in 2013 to peak between 7.3 and 11.6 TWp yr–1 in the late 2030s, for an early or a late fossil-fuel phase-out respectively in order for emissions to stay within the recommended CO2 budget.

  12. The sower’s way: quantifying the narrowing net-energy pathways to a global energy transition

    NASA Astrophysics Data System (ADS)

    Sgouridis, Sgouris; Csala, Denes; Bardi, Ugo

    2016-09-01

    Planning the appropriate renewable energy (RE) installation rate should balance two partially contradictory objectives: substituting fossil fuels fast enough to stave-off the worst consequences of climate change while maintaining a sufficient net energy flow to support the world’s economy. The upfront energy invested in constructing a RE infrastructure subtracts from the net energy available for societal energy needs, a fact typically neglected in energy projections. Modeling feasible energy transition pathways to provide different net energy levels we find that they are critically dependent on the fossil fuel emissions cap and phase-out profile and on the characteristic energy return on energy invested of the RE technologies. The easiest pathway requires installation of RE plants to accelerate from 0.12 TWp yr-1 in 2013 to peak between 7.3 and 11.6 TWp yr-1 in the late 2030s, for an early or a late fossil-fuel phase-out respectively in order for emissions to stay within the recommended CO2 budget.

  13. Landau-Zener transitions mediated by an environment: Population transfer and energy dissipation

    SciTech Connect

    Dodin, Amro; Simine, Lena; Segal, Dvira; Garmon, Savannah

    2014-03-28

    We study Landau-Zener transitions between two states with the addition of a shared discretized continuum. The continuum allows for population decay from the initial state as well as indirect transitions between the two states. The probability of nonadiabatic transition in this multichannel model preserves the standard Landau-Zener functional form except for a shift in the usual exponential factor, reflecting population transfer into the continuum. We provide an intuitive explanation for this behavior assuming individual, independent transitions between pairs of states. In contrast, the ground state survival probability at long time shows a novel, non-monotonic, functional form with an oscillatory behavior in the sweep rate at low sweep rate values. We contrast the behavior of this open-multistate model to other generalized Landau-Zener models incorporating an environment: the stochastic Landau-Zener model and the dissipative case, where energy dissipation and thermal excitations affect the adiabatic region. Finally, we present evidence that the continuum of states may act to shield the two-state Landau-Zener transition probability from the effect of noise.

  14. Interacting cosmic fluids and phase transitions under a holographic modeling for dark energy

    NASA Astrophysics Data System (ADS)

    Lepe, Samuel; Peña, Francisco

    2016-09-01

    We discuss the consequences of possible sign changes of the Q-function which measures the transfer of energy between dark energy and dark matter. We investigate this scenario from a holographic perspective by modeling dark energy by a linear parametrization and CPL-parametrization of the equation of state (ω ). By imposing the strong constraint of the second law of thermodynamics, we show that the change of sign for Q, due to the cosmic evolution, imply changes in the temperatures of dark energy and dark matter. We also discuss the phase transitions, in the past and future, experienced by dark energy and dark matter (or, equivalently, the sign changes of their heat capacities).

  15. Nutrition transition and dietary energy availability in Eastern Europe after the collapse of communism.

    PubMed

    Ulijaszek, Stanley J; Koziel, Slawomir

    2007-12-01

    After the economic transition of the late 1980s and early 1990s there was a rapid increase in overweight and obesity in many countries of Eastern Europe. This article describes changing availability of dietary energy from major dietary components since the transition to free-market economic systems among Eastern European nations, using food balance data obtained at national level for the years 1990-92 and 2005 from the FAOSTAT-Nutrition database. Dietary energy available to the East European nations satellite to the former Soviet Union (henceforth, Eastern Europe) was greater than in the nations of the former Soviet Union. Among the latter, the Western nations of the former Soviet Union had greater dietary energy availability than the Eastern and Southern nations of the former Soviet Union. The higher energy availability in Eastern Europe relative to the nations of the former Soviet Union consists mostly of high-protein foods. There has been no significant change in overall dietary energy availability to any category of East European nation between 1990-1992 and 2005, indicating that, at the macro-level, increasing rates of obesity in Eastern European countries cannot be attributed to increased dietary energy availability. The most plausible macro-level explanations for the obesity patterns observed in East European nations are declines in physical activity, increased real income, and increased consumption of goods that contribute to physical activity decline: cars, televisions and computers.

  16. A cautionary approach in transitioning to 'green' energy technologies and practices is required.

    PubMed

    Matatiele, Puleng; Gulumian, Mary

    2016-06-01

    Renewable energy technologies (wind turbines, solar cells, biofuels, etc.) are often referred to as 'clean' or 'green' energy sources, while jobs linked to the field of environmental protection and energy efficiency are referred to as 'green' jobs. The energy efficiency of clean technologies, which is likely to reduce and/or eliminate reliance on fossil fuels, is acknowledged. However, the potential contribution of green technologies and associated practices to ill health and environmental pollution resulting from consumption of energy and raw materials, generation of waste, and the negative impacts related to some life cycle phases of these technologies are discussed. Similarly, a point is made that the green jobs theme is mistakenly oversold because the employment opportunities generated by transitioning to green technologies are not necessarily safe and healthy jobs. Emphasis is put on identifying the hazards associated with these green designs, assessing the risks to the environment and worker health and safety, and either eliminating the hazards or minimizing the risks as essential elements to the design, construction, operation, and maintenance of green technologies. The perception that it is not always economically possible to consider all risk factors associated with renewable energy technologies at the beginning without hampering their implementation, especially in the poor developing countries, is dismissed. Instead, poor countries are encouraged to start implementing environmentally sound practices while transitioning to green technologies in line with their technological development and overall economic growth. PMID:27180334

  17. Energy calibration of superconducting transition edge sensors for x-ray detection using pulse analysis

    SciTech Connect

    Hollerith, C.; Simmnacher, B.; Weiland, R.; Feilitzsch, F. v.; Isaila, C.; Jochum, J.; Potzel, W.; Hoehne, J.; Phelan, K.; Wernicke, D.; May, T.

    2006-05-15

    Transition edge sensors (TESs) have been developed to be used as high-resolution x-ray detectors. They show excellent energy resolution and can be used in many applications. TESs are a special kind of calorimeters that can determine small temperature changes after x-ray absorption. Such a temperature change causes a strong resistance change (superconducting to normal-conducting phase transition) that can be measured. The energy calibration of a TES based spectrometer is problematic due to the nonlinear behavior of the detector response. In this article, a method is introduced to calibrate the energy scale of TES spectra. This is accomplished by calculating the energy dependence of the response of the detector operated in electrothermal feedback mode. Using this method a calibration accuracy of a few eV for an x-ray energy of 6 keV can be achieved. Examples of energy dispersive x-ray spectroscopy (EDS) measurements demonstrate the high quality of this method for everyday use of TES EDS detectors in material analysis. However, because the method relies only on a few very general assumptions, it should also be useful for other kinds of TES detectors.

  18. A cautionary approach in transitioning to 'green' energy technologies and practices is required.

    PubMed

    Matatiele, Puleng; Gulumian, Mary

    2016-06-01

    Renewable energy technologies (wind turbines, solar cells, biofuels, etc.) are often referred to as 'clean' or 'green' energy sources, while jobs linked to the field of environmental protection and energy efficiency are referred to as 'green' jobs. The energy efficiency of clean technologies, which is likely to reduce and/or eliminate reliance on fossil fuels, is acknowledged. However, the potential contribution of green technologies and associated practices to ill health and environmental pollution resulting from consumption of energy and raw materials, generation of waste, and the negative impacts related to some life cycle phases of these technologies are discussed. Similarly, a point is made that the green jobs theme is mistakenly oversold because the employment opportunities generated by transitioning to green technologies are not necessarily safe and healthy jobs. Emphasis is put on identifying the hazards associated with these green designs, assessing the risks to the environment and worker health and safety, and either eliminating the hazards or minimizing the risks as essential elements to the design, construction, operation, and maintenance of green technologies. The perception that it is not always economically possible to consider all risk factors associated with renewable energy technologies at the beginning without hampering their implementation, especially in the poor developing countries, is dismissed. Instead, poor countries are encouraged to start implementing environmentally sound practices while transitioning to green technologies in line with their technological development and overall economic growth.

  19. Excitation energy transfer in partly ordered polymer films differing in donor and acceptor transition moments orientation

    NASA Astrophysics Data System (ADS)

    Synak, A.; Bojarski, P.; Sadownik, M.; Kułak, L.; Gryczynski, I.; Grobelna, B.; Rangełowa-Jankowska, S.; Jankowski, D.; Kubicki, A.

    2016-09-01

    Based on spectroscopic measurements selected properties of nonradiative Förster energy transport are studied in uniaxially stretched polyvinyl alcohol thin films for three systems differing in donor and acceptor transition moments orientation relative to the axis of stretching. In particular, donor - acceptor emission anisotropy spectra yield completely different regularities for these systems in uniaxially stretched films, whereas they are similar in unstretched films. In particular it is shown that acceptor fluorescence can be either strongly polarized after nonradiative energy transfer in stretched films or depolarized depending on the angular distribution of acceptor transition moments in the matrix. Donor and acceptor emission anisotropy decays exhibit similar regularities to those of steady-state measurements. The obtained results are analyzed with the help of Monte Carlo simulations.

  20. Non-resonant electromechanical energy harvesting using inter-ferroelectric phase transitions

    SciTech Connect

    Pérez Moyet, Richard; Rossetti, George A.; Stace, Joseph; Amin, Ahmed; Finkel, Peter

    2015-10-26

    Non-resonant electromechanical energy harvesting is demonstrated under low frequency excitation (<50 Hz) using [110]{sub C}-poled lead indium niobate-lead magnesium niobate-lead titanate relaxor ferroelectric single crystals with compositions near the morphotropic phase boundary. The efficiency of power generation at the stress-induced phase transition between domain-engineered rhombohedral and orthorhombic ferroelectric states is as much as four times greater than is obtained in the linear piezoelectric regime under identical measurement conditions but during loading below the coercive stress of the phase change. The phase transition mode of electromechanical transduction holds potential for non-resonant energy harvesting from low-frequency vibrations and does not require mechanical frequency up-conversion.

  1. Inverse parabolic quantum dot: The transition energy under magnetic field effect

    NASA Astrophysics Data System (ADS)

    Safwan, S. A.; El Meshed, Nagwa

    2016-08-01

    We present here, the evolution of the transition energy with a static magnetic field, when the electron and the hole are confined in inverse parabolic quantum dot (IPQD). The unexpected behavior is found, at the weak confinement regime the conduction band minimum and the top of valance band change from s-state to p-state or d-state for confined electron and hole inside IPQD, respectively. The strength of the inverse parabolic potential (potential hump) inside a quantum dot has the upper hand in tuning the ground state momentum for both electron and hole, and consequently their interband transition energy is changed. Knowing that this is not the case for the other types of potentials. The quantum size, the magnetic field and inverse potential hump effects on electron and hole ground and excited states are discussed.

  2. Energy levels and radiative rates for transitions in Cr-like Co IV and Ni V

    NASA Astrophysics Data System (ADS)

    Aggarwal, K. M.; Bogdanovich, P.; Karpuškienė, R.; Keenan, F. P.; Kisielius, R.; Stancalie, V.

    2016-01-01

    We report calculations of energy levels and radiative rates (A-values) for transitions in Cr-like Co IV and Ni V. The quasi-relativistic Hartree-Fock (QRHF) code is adopted for calculating the data although GRASP (general-purpose relativistic atomic structure package) and flexible atomic code (FAC) have also been employed for comparison purposes. No radiative rates are available in the literature to compare with our results, but our calculated energies are in close agreement with those compiled by NIST for a majority of the levels. However, there are discrepancies for a few levels of up to 3%. The A-values are listed for all significantly contributing E1, E2 and M1 transitions, and the corresponding lifetimes reported, although unfortunately no previous theoretical or experimental results exist to compare with our data.

  3. An anxious time? Exploring the nature of worries experienced by young people with a mild to moderate intellectual disability as they make the transition to adulthood.

    PubMed

    Forte, Marisa; Jahoda, Andrew; Dagnan, Dave

    2011-11-01

    OBJECTIVES. Transition to adulthood can be a challenging time for all young people. However, this period of change is likely to be more difficult for those with mild intellectual disabilities (IDs) because they are often more socially marginalized, remain more dependent upon their family, and have fewer options for future careers than their typically developing peers. Therefore, this study examines the content and salience of worries experienced by young people with mild ID during transition to adulthood, and whether the above disadvantages are associated with the level of reported anxiety and their sense of self-efficacy. DESIGN AND METHODS. Fifty-two participants (17-20 years) took part; 26 with mild ID and 26 typically developing adults. Of interest were potential differences between groups in (1) worries described; (2) salience of worries; and (3) associations between self-efficacy, anxiety, and worry within groups. Participants completed a 'worry' interview, the General Self Efficacy Scale-12 and the Glasgow Anxiety Scale-LD. RESULTS. It was found that the ID group's most salient worries (being bullied, losing someone they are dependent upon, failing in life, followed by making and keeping friends) were largely different from their non-disabled peers (getting a job, followed by not having enough surplus money, failing, and having to make decisions about their future choices) at this stage of transition. Not only was there a difference in the nature of worries expressed, but the intellectually disabled group also reported ruminating significantly more about their worries and being more distressed by them. CONCLUSION. Obtaining insight into worries at transition may help to target efforts at increasing these young people's resilience. Clinical applications of the findings are discussed. PMID:22003949

  4. An anxious time? Exploring the nature of worries experienced by young people with a mild to moderate intellectual disability as they make the transition to adulthood.

    PubMed

    Forte, Marisa; Jahoda, Andrew; Dagnan, Dave

    2011-11-01

    OBJECTIVES. Transition to adulthood can be a challenging time for all young people. However, this period of change is likely to be more difficult for those with mild intellectual disabilities (IDs) because they are often more socially marginalized, remain more dependent upon their family, and have fewer options for future careers than their typically developing peers. Therefore, this study examines the content and salience of worries experienced by young people with mild ID during transition to adulthood, and whether the above disadvantages are associated with the level of reported anxiety and their sense of self-efficacy. DESIGN AND METHODS. Fifty-two participants (17-20 years) took part; 26 with mild ID and 26 typically developing adults. Of interest were potential differences between groups in (1) worries described; (2) salience of worries; and (3) associations between self-efficacy, anxiety, and worry within groups. Participants completed a 'worry' interview, the General Self Efficacy Scale-12 and the Glasgow Anxiety Scale-LD. RESULTS. It was found that the ID group's most salient worries (being bullied, losing someone they are dependent upon, failing in life, followed by making and keeping friends) were largely different from their non-disabled peers (getting a job, followed by not having enough surplus money, failing, and having to make decisions about their future choices) at this stage of transition. Not only was there a difference in the nature of worries expressed, but the intellectually disabled group also reported ruminating significantly more about their worries and being more distressed by them. CONCLUSION. Obtaining insight into worries at transition may help to target efforts at increasing these young people's resilience. Clinical applications of the findings are discussed.

  5. Energy Transition Initiative: Island Energy Snapshot - Bonaire; U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    This profile provides a snapshot of the energy landscape of Bonaire, a special municipality of the Kingdom of the Netherlands located off the coast of Venezuela. Bonaire’s utility rates are approximately $0.35 per kilowatt-hour (kWh), above the Caribbean regional average of $0.33/kWh.

  6. Energy Transition Initiative: Island Energy Snapshot - Barbados; U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    This profile provides a snapshot of the energy landscape of Barbados, an independent nation in the Lesser Antilles island chain in the eastern Caribbean. Barbados’ electricity rates are approximately $0.28 per kilowatt-hour (kWh), below the Caribbean regional average of $0.33/kWh.

  7. Energy Transition Initiative: Island Energy Snapshot - Curacao; U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    This profile provides a snapshot of the energy landscape of Curacao, an autonomous member of the Kingdom of the Netherlands located off the coast of Venezuela. Curacao’s utility rates are approximately $0.26 per kilowatt-hour (kWh), below the Caribbean regional average of $0.33/kWh.

  8. Energy Transition Initiative: Island Energy Snapshot - Haiti; U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    This profile provides a snapshot of the energy landscape of Haiti, an independent nation that occupies the western portion of the island of Hispaniola in the northern Caribbean Sea. Haiti’s utility rates are roughly $0.35 U.S. dollars (USD) per kilowatt-hour (kWh), above the Caribbean regional average of $0.33 USD/kWh.

  9. Energy Transition Initiative: Island Energy Snapshot - American Samoa; U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    This profile provides a snapshot of the energy landscape of American Samoa, the southernmost territory of the United States. American Samoa’s residential electricity rates are approximately $0.29 U.S. dollars (USD) per kilowatt-hour (kWh), more than twice the average U.S. residential rate of $0.13 USD/kWh.

  10. Energy Transition Initiative: Island Energy Snapshot - Palau; U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    This profile provides a snapshot of the energy landscape of Palau, an independent island nation geographically located in the Micronesia region. Palau’s residential electricity rates are approximately $0.28 U.S. dollars (USD) per kilowatt-hour (kWh), more than twice the average U.S. residential rate of $0.13 USD/kWh.

  11. Low-cost transitional care with nurse managers making mostly phone contact with patients cut rehospitalization at a VA hospital.

    PubMed

    Kind, Amy J H; Jensen, Laury; Barczi, Steve; Bridges, Alan; Kordahl, Rebecca; Smith, Maureen A; Asthana, Sanjay

    2012-12-01

    The Coordinated-Transitional Care (C-TraC) Program was designed to improve care coordination and outcomes among veterans with high-risk conditions discharged to community settings from the William S. Middleton Memorial Veterans Hospital, in Madison, Wisconsin. Under the program, patients work with nurse case managers on care and health issues, including medication reconciliation, before and after hospital discharge, with all contacts made by phone once the patient is at home. Patients who received the C-TraC protocol experienced one-third fewer rehospitalizations than those in a baseline comparison group, producing an estimated savings of $1,225 per patient net of programmatic costs. This model requires a relatively small amount of resources to operate and may represent a viable alternative for hospitals seeking to offer improved transitional care as encouraged by the Affordable Care Act. In particular, the model may be attractive for providers in rural areas or other care settings challenged by wide geographic dispersion of patients or by constrained resources. PMID:23213150

  12. Low-Cost Transitional Care With Nurse Managers Making Mostly Phone Contact With Patients Cut Rehospitalization At A VA Hospital

    PubMed Central

    Kind, Amy J.H.; Jensen, Laury; Barczi, Steve; Bridges, Alan; Kordahl, Becky; Smith, Maureen A.; Asthana, Sanjay

    2012-01-01

    The Coordinated-Transitional Care (C-TraC) Program was designed to improve care coordination and outcomes among veterans with high-risk conditions discharged to community settings from the William S. Middleton Memorial Veterans Hospital, in Madison, Wisconsin. Under the program, patients work with nurse case managers on care and health issues, including medication reconciliation, before and after hospital discharge, with all contacts made by phone once the patient is at home. Patients who received the C-TraC protocol experienced one-third fewer rehospitalizations than those in a baseline comparison group, producing an estimated savings of $1,225 per patient net of programmatic costs. This model requires a relatively low amount of resources to operate and may represent a viable alternative for hospitals seeking to offer improved transitional care as encouraged by the Affordable Care Act. In particular, the model may be attractive for providers in rural areas or other care settings challenged by wide geographic dispersion of patients or by constrained resources. PMID:23213150

  13. The DeStress for Success Program: effects of a stress education program on cortisol levels and depressive symptomatology in adolescents making the transition to high school.

    PubMed

    Lupien, S J; Ouellet-Morin, I; Trépanier, L; Juster, R P; Marin, M F; Francois, N; Sindi, S; Wan, N; Findlay, H; Durand, N; Cooper, L; Schramek, T; Andrews, J; Corbo, V; Dedovic, K; Lai, B; Plusquellec, P

    2013-09-26

    Various studies have shown that increased activity of the hypothalamic-pituitary-adrenal (HPA) axis can predict the onset of adolescent depressive symptomatology. We have previously shown that adolescents making the transition to high school present a significant increase in cortisol levels, the main product of HPA axis activation. In the present study, we evaluated whether a school-based education program developed according to the current state of knowledge on stress in psychoneuroendocrinology decreases cortisol levels and/or depressive symptoms in adolescents making the transition to high school. Participants were 504 Year 7 high school students from two private schools in the Montreal area. Adolescents of one school were exposed to the DeStress for Success Program while adolescents from the other school served as controls. Salivary cortisol levels and depressive symptomatology were measured before, immediately after as well as 3 months after exposure to the program. Measures of negative mood were obtained at baseline in order to determine whether adolescents starting high school with specific negative moods were differentially responsive to the program. The results show that only adolescents starting high school with high levels of anger responded to the intervention with a significant decrease in cortisol levels. Moreover, we found that adolescents who took part in the intervention and showed decreasing cortisol levels following the intervention (responders) were 2.45 times less at risk to suffer from clinical and subclinical depressive states three months post-intervention in comparison to adolescents who showed increasing cortisol levels following the intervention (nonresponders). This study provides the first evidence that a school-based program on stress is effective at decreasing cortisol levels and depressive symptomatology in adolescents making the transition to high school and it helps explain which adolescents are sensitive to the program and what

  14. Strain controlled ferromagnetic-ferrimagnetic transition and vacancy formation energy of defective graphene

    NASA Astrophysics Data System (ADS)

    Zhang, Yajun; Sahoo, MPK; Wang, Jie

    2016-10-01

    Single vacancy (SV)-induced magnetism in graphene has attracted much attention motivated by its potential in achieving new functionalities. However, a much higher vacancy formation energy limits its direct application in electronic devices and the dependency of spin interaction on the strain is unclear. Here, through first-principles density-functional theory calculations, we investigate the possibility of strain engineering towards lowering vacancy formation energy and inducing new magnetic states in defective graphene. It is found that the SV-graphene undergoes a phase transition from an initial ferromagnetic state to a ferrimagnetic state under a biaxial tensile strain. At the same time, the biaxial tensile strain significantly lowers the vacancy formation energy. The charge density, density of states and band theory successfully identify the origin and underlying physics of the transition. The predicted magnetic phase transition is attributed to the strain driven spin flipping at the C-atoms nearest to the SV-site. The magnetic semiconducting graphene induced by defect and strain engineering suggests an effective way to modulate both spin and electronic degrees of freedom in future spintronic devices.

  15. Energy calibration issues in nuclear resonant vibrational spectroscopy: observing small spectral shifts and making fast calibrations.

    PubMed

    Wang, Hongxin; Yoda, Yoshitaka; Dong, Weibing; Huang, Songping D

    2013-09-01

    The conventional energy calibration for nuclear resonant vibrational spectroscopy (NRVS) is usually long. Meanwhile, taking NRVS samples out of the cryostat increases the chance of sample damage, which makes it impossible to carry out an energy calibration during one NRVS measurement. In this study, by manipulating the 14.4 keV beam through the main measurement chamber without moving out the NRVS sample, two alternative calibration procedures have been proposed and established: (i) an in situ calibration procedure, which measures the main NRVS sample at stage A and the calibration sample at stage B simultaneously, and calibrates the energies for observing extremely small spectral shifts; for example, the 0.3 meV energy shift between the 100%-(57)Fe-enriched [Fe4S4Cl4](=) and 10%-(57)Fe and 90%-(54)Fe labeled [Fe4S4Cl4](=) has been well resolved; (ii) a quick-switching energy calibration procedure, which reduces each calibration time from 3-4 h to about 30 min. Although the quick-switching calibration is not in situ, it is suitable for normal NRVS measurements.

  16. Making Homes Part of the Climate Solution: Policy Options To Promote Energy Efficiency

    SciTech Connect

    Brown, Dr. Marilyn Ann; Chandler, Jess; Lapsa, Melissa Voss; Ally, Moonis

    2009-06-01

    In the area of energy efficiency, advanced technologies combined with best practices appear to afford not only large, but also cost-effective options to conserve energy and reduce greenhouse gas emissions (McKinsey & Company, 2007). In practice, however, the realization of this potential has often proven difficult. Progress appears to require large numbers of individuals to act knowledgeably, and each individual must often act with enabling assistance from others. Even when consumer education is effective and social norms are supportive, the actions of individuals and businesses can be impeded by a broad range of barriers, many of which are non-technical in nature. Title XVI of the Energy Policy Act of 2005 included a mandate to examine barriers to progress and make recommendations in this regard. A detailed report on barriers as well as the National strategy for overcoming barriers met this requirement (Brown et al, 2008; CCCSTI, 2009). Following up on this mandate, the U.S. Climate Change Technology Program (CCTP) chose to focus next on the development of policy options to improve energy efficiency in residential buildings, with supporting analysis of pros and cons, informed in part by behavioral research. While this work is sponsored by CCTP, it has been undertaken in coordination with DOE's Building Technologies Program and Office of Electricity Delivery and Energy Reliability.

  17. Large Hybrid Energy Systems for Making Low CO2 Load-Following Power and Synthetic Fuel

    SciTech Connect

    Robert S. Cherry; Richard D. Boardman; Steven Aumeier

    2012-02-01

    Hybrid energy systems using nuclear heat sources can economically produce load-following electrical power by exploiting the surplus generation capacity available at night or seasonally to make synthetic fuel. Vehicle fuel is the only current energy use large enough to absorb all the energy capacity that might be diverted from the power industry, and its ease of storage obviates problems with discontinuous synfuel production. The potential benefits and challenges of synfuels integration are illustrated by the production of methanol from natural gas (as a source of carbon) using steam from a light water nuclear power reactor which is assumed to be available in accord with a year's worth of power demand data. Methanol's synthesis process is easily adapted to using 300 C heat from a light water reactor and this simple compound can be further processed into gasoline, biodiesel, or dimethyl ether, fuels which can be used with the current vehicle fleet. A supplemental feed to the methanol process of natural gas (for energy) allows operation at constant full rate when the nuclear heat is being used to produce electrical power. The higher capital costs of such a system are offset by a lower cost of heat and power production from a large base load type of plant and by reduced costs associated with much lower CO2 emissions. Other less tangible economic benefits of this and similar hybrid systems include better use of natural resource for fuels and greater energy services security from the domestic production of vehicle fuel.

  18. Critical high-dimensional state transitions in cell populations or why cancers follow the principle ``What does not kill me makes me stronger''

    NASA Astrophysics Data System (ADS)

    Huang, Sui

    Transitions between high-dimensional attractor states in the quasi-potential landscape of the gene regulatory network, induced by environmental perturbations and/or facilitated by mutational rewiring of the network, underlie cell phenotype switching in development as well as in cancer progression, including acquisition of drug-resistant phenotypes. Considering heterogeneous cell populations as statistical ensembles of cells, and single-cell resolution gene expression profiling of cell populations undergoing a cell phenotype shift allow us now to map the topography of the landscape and its distortion. From snapshots of single-cell expression patterns of a cell population measured during major transitions we compute a quantity that identifies symmetry-breaking destabilization of attractors (bifurcation) and concomitant dimension-reduction of the state space manifold (landscape distortion) which precede critical transitions to new attractor states. The model predicts, and we show experimentally, the almost inevitable generation of aberrant cells associated with such critical transitions in multi-attractor landscapes: therapeutic perturbations which seek to push cancer cells to the apoptotic state, almost always produce ``rebellious'' cells which move in the ``opposite direction'': instead of dying they become more stem-cell-like and malignant. We show experimentally that the inadvertent generation of more malignant cancer cells by therapy indeed results from transition of surviving (but stressed) cells into unforeseen attractor states and not simply from selection of inherently more resistant cells. Thus, cancer cells follow not so much Darwin, as generally thought (survival of the fittest), but rather Nietzsche (What does not kill me makes me stronger). Supported by NIH (NCI, NIGMS), Alberta Innovates.

  19. What Patients With Severe Mental Illness Transitioning From Hospital to Community Have to Say About Care and Shared Decision-Making.

    PubMed

    Velligan, Dawn I; Roberts, David L; Sierra, Cynthia; Fredrick, Megan M; Roach, Mary Jo

    2016-06-01

    Shared decision-making (SDM) has been slow to disseminate in mental health. We conducted focus groups with ten individuals with serious mental illness (SMI) treated in a 90 day, outpatient transitional care clinic. Parallel groups were held with family caregivers (n = 8). Individuals with SMI wanted longer visits, to have their stories heard, more information about options presented simply, to hear from peers about similar experiences, and a bigger say in treatment choices. Caregivers wanted to be invited to participate to a larger extent.  Results suggest that after a decade, SDM may not have the expected penetration in community mental health.

  20. Students' Energy Concepts at the Transition Between Primary and Secondary School

    NASA Astrophysics Data System (ADS)

    Opitz, Sebastian T.; Harms, Ute; Neumann, Knut; Kowalzik, Kristin; Frank, Arne

    2015-10-01

    Energy is considered both a core idea and a crosscutting concept in science education. A thorough understanding of the energy concept is thought to help students learn about other (related) concepts within and across science subjects, thereby fostering scientific literacy. This study investigates students' progression in understanding the energy concept in biological contexts at the transition from primary to lower secondary school by employing a quantitative, cross-sectional study in grades 3-6 ( N = 540) using complex multiple-choice items. Based on a model developed in a previous study, energy concepts were assessed along four aspects of energy: (1) forms and sources of energy, (2) transfer and transformation, (3) degradation and dissipation, and (4) energy conservation. Two parallel test forms (A and B) indicated energy concept scores to increase significantly by a factor of 2.3 (A)/1.7 (B) from grade 3 to grade 6. Students were observed to progress in their understanding of all four aspects of the concept and scored highest on items for energy forms. The lowest scores and the smallest gain across grades were found for energy conservation. Based on our results, we argue that despite numerous learning opportunities, students lack a more integrated understanding of energy at this stage, underlining the requirement of a more explicit approach to teaching energy to young learners. Likewise, more interdisciplinary links for energy learning between relevant contexts in each science discipline may enable older students to more efficiently use energy as a tool and crosscutting concept with which to analyze complex content.

  1. Potential energy landscapes for the 2D XY model: Minima, transition states, and pathways

    NASA Astrophysics Data System (ADS)

    Mehta, Dhagash; Hughes, Ciaran; Schröck, Mario; Wales, David J.

    2013-11-01

    We describe a numerical study of the potential energy landscape for the two-dimensional XY model (with no disorder), considering up to 100 spins and central processing unit and graphics processing unit implementations of local optimization, focusing on minima and saddles of index one (transition states). We examine both periodic and anti-periodic boundary conditions, and show that the number of stationary points located increases exponentially with increasing lattice size. The corresponding disconnectivity graphs exhibit funneled landscapes; the global minima are readily located because they exhibit relatively large basins of attraction compared to the higher energy minima as the lattice size increases.

  2. Energy Transition Initiative: Island Energy Snapshot - Guam; U.S. Department of Energy (DOE), NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    This profile provides a snapshot of the energy landscape of Guam, an island territory of the United States located in the western Pacific Ocean. Guam’s electricity rates for residential customers start at $0.21 U.S. dollars (USD) per kilowatt-hour (kWh), above the average U.S. rate of $0.13 USD/kWh.1,2 Like

  3. Energy Efficiency Improvement and Cost Saving Opportunities for Cement Making. An ENERGY STAR Guide for Energy and Plant Managers

    SciTech Connect

    Galitsky, Christina; Worrell, Ernst; Galitsky, Christina

    2008-01-01

    The cost of energy as part of the total production costs in the cement industry is significant, warranting attention for energy efficiency to improve the bottom line. Historically, energy intensity has declined, although more recently energy intensity seems to have stabilized with the gains. Coal and coke are currently the primary fuels for the sector, supplanting the dominance of natural gas in the 1970s. Most recently, there is a slight increase in the use of waste fuels, including tires. Between 1970 and 1999, primary physical energy intensity for cement production dropped 1 percent/year from 7.3 MBtu/short ton to 5.3 MBtu/short ton. Carbon dioxide intensity due to fuel consumption and raw material calcination dropped 16 percent, from 609 lb. C/ton of cement (0.31 tC/tonne) to 510 lb. C/ton cement (0.26 tC/tonne). Despite the historic progress, there is ample room for energy efficiency improvement. The relatively high share of wet-process plants (25 percent of clinker production in 1999 in the U.S.) suggests the existence of a considerable potential, when compared to other industrialized countries. We examined over 40 energy efficient technologies and measures and estimated energy savings, carbon dioxide savings, investment costs, and operation and maintenance costs for each of the measures. The report describes the measures and experiences of cement plants around the wold with these practices and technologies. Substantial potential for energy efficiency improvement exists in the cement industry and in individual plants. A portion of this potential will be achieved as part of (natural) modernization and expansion of existing facilities, as well as construction of new plants in particular regions. Still, a relatively large potential for improved energy management practices exists.

  4. Energy levels and transition rates for helium-like ions with Z = 10-36

    NASA Astrophysics Data System (ADS)

    Si, R.; Guo, X. L.; Wang, K.; Li, S.; Yan, J.; Chen, C. Y.; Brage, T.; Zou, Y. M.

    2016-08-01

    Aims: Helium-like ions provide an important X-ray spectral diagnostics in astrophysical and high-temperature fusion plasmas. An interpretation of the observed spectra provides information on temperature, density, and chemical compositions of the plasma. Such an analysis requires information for a wide range of atomic parameters, including energy levels and transition rates. Our aim is to provide a set of accurate energy levels and transition rates for helium-like ions with Z = 10-36. Methods: The second-order many-body perturbation theory (MBPT) was adopted in this paper. To support our MBPT results, we performed an independent calculation using the multiconfiguration Dirac-Hartree-Fock (MCDHF) method. Results: We provide accurate energies for the lowest singly excited 70 levels among 1snl(n ≤ 6,l ≤ (n-1)) configurations and the lowest doubly excited 250 levels arising from the K-vacancy 2ln'l'(n' ≤ 6,l' ≤ (n'-1)) configurations of helium-like ions with Z = 10-36. Wavelengths, transition rates, oscillator strengths, and line strengths are calculated for the E1, M1, E2, and M2 transitions among these levels. The radiative lifetimes are reported for all the calculated levels. Conclusions: Our MBPT results for singly excited n ≤ 2 levels show excellent agreement with other elaborate calculations, while those for singly excited n ≥ 3 and doubly excited levels show significant improvements over previous theoretical results. Our results will be very helpful for astrophysical line identification and plasma diagnostics. Full Tables 1 and 2 are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/592/A141

  5. Earth-to-Moon low energy transfers targeting L1 hyperbolic transit orbits.

    PubMed

    Topputo, Francesco; Vasile, Massimiliano; Bernelli-Zazzera, Franco

    2005-12-01

    In the frame of the lunar exploration, numerous future space missions will require maximization of payload mass, and simultaneously achieving reasonable transfer times. To fulfill this request, low energy non-Keplerian orbits could be used to reach the Moon instead of high energetic transfers. The low energy solutions can be separated into two main categories depending on the nature of the trajectory approaching the Moon: low energy transit orbits that approach the Moon from the interior equilibrium point L(1) and weak stability boundary transfers that reach the Moon after passing through L(2). This paper proposes an alternative way to exploit the opportunities offered by L(1) transit orbits for the design of Earth-Moon transfers. First, in a neighborhood of the L(1) point, the three-body dynamics is linearized and written in normal form; then the entire family of nonlinear transit orbits is obtained by selecting the appropriate nontrivial amplitudes associated with the hyperbolic part. The L(1)-Earth arc is close to a 5:2 resonant orbit with the Moon, whose perturbations cause the apogee to rise. In a second step, two selected low altitude parking orbits around the Earth and the Moon are linked with the transit orbit by means of two three-body Lambert arcs, solutions of two two-point boundary value problems. The resulting Earth-to-Moon trajectories prove to be very efficient in the Moon captured arc and save approximately 100 m/sec in Deltav cost when compared to the Hohmann transfer. Furthermore, such solutions demonstrate that Moon capture could be obtained in the frame of the Earth-Moon R3BP neglecting the presence of the Sun.

  6. High-energy resolution electron energy-loss spectroscopy study of interband transitions characteristic to single-walled carbon nanotubes.

    PubMed

    Sato, Yohei; Terauchi, Masami

    2014-06-01

    An electron energy-loss spectroscopic (EELS) study using a monochromator transmission electron microscope was conducted for investigating the dielectric response of isolated single-walled carbon nanotubes (SWCNTs) owing to interband transitions characteristic to chiral structures. Individual chiral structures of the SWCNTs were determined by electron diffraction patterns. EELS spectra obtained from isolated SWCNTs showed sharp peaks below π plasmon energy of 5 eV, which were attributed to the characteristic interband transitions of SWCNTs. In addition, unexpected shoulder structures were observed at the higher energy side of each sharp peak. Simulations of EELS spectra by using the continuum dielectric theory showed that an origin of the shoulder structures was because of the surface dipole mode along the circumference direction of the SWCNT. It was noticed that the electron excitation energies obtained by EELS were slightly higher than those of optical studies, which might be because of the inelastic scattering process with the momentum transfers. To interpret the discrepancy between the EELS and optical experiments, it is necessary to conduct more accurate simulation including the first principle calculation for the band structure of SWCNTs.

  7. Optical transition radiation used in the diagnostic of low energy and low current electron beams in particle accelerators

    SciTech Connect

    Silva, T. F.; Bonini, A. L.; Lima, R. R.; Maidana, N. L.; Malafronte, A. A.; Pascholati, P. R.; Vanin, V. R.; Martins, M. N.

    2012-09-15

    Optical transition radiation (OTR) plays an important role in beam diagnostics for high energy particle accelerators. Its linear intensity with beam current is a great advantage as compared to fluorescent screens, which are subject to saturation. Moreover, the measurement of the angular distribution of the emitted radiation enables the determination of many beam parameters in a single observation point. However, few works deals with the application of OTR to monitor low energy beams. In this work we describe the design of an OTR based beam monitor used to measure the transverse beam charge distribution of the 1.9-MeV electron beam of the linac injector of the IFUSP microtron using a standard vision machine camera. The average beam current in pulsed operation mode is of the order of tens of nano-Amps. Low energy and low beam current make OTR observation difficult. To improve sensitivity, the beam incidence angle on the target was chosen to maximize the photon flux in the camera field-of-view. Measurements that assess OTR observation (linearity with beam current, polarization, and spectrum shape) are presented, as well as a typical 1.9-MeV electron beam charge distribution obtained from OTR. Some aspects of emittance measurement using this device are also discussed.

  8. Optical transition radiation used in the diagnostic of low energy and low current electron beams in particle accelerators.

    PubMed

    Silva, T F; Bonini, A L; Lima, R R; Maidana, N L; Malafronte, A A; Pascholati, P R; Vanin, V R; Martins, M N

    2012-09-01

    Optical transition radiation (OTR) plays an important role in beam diagnostics for high energy particle accelerators. Its linear intensity with beam current is a great advantage as compared to fluorescent screens, which are subject to saturation. Moreover, the measurement of the angular distribution of the emitted radiation enables the determination of many beam parameters in a single observation point. However, few works deals with the application of OTR to monitor low energy beams. In this work we describe the design of an OTR based beam monitor used to measure the transverse beam charge distribution of the 1.9-MeV electron beam of the linac injector of the IFUSP microtron using a standard vision machine camera. The average beam current in pulsed operation mode is of the order of tens of nano-Amps. Low energy and low beam current make OTR observation difficult. To improve sensitivity, the beam incidence angle on the target was chosen to maximize the photon flux in the camera field-of-view. Measurements that assess OTR observation (linearity with beam current, polarization, and spectrum shape) are presented, as well as a typical 1.9-MeV electron beam charge distribution obtained from OTR. Some aspects of emittance measurement using this device are also discussed.

  9. Characterizing metastable states beyond energies and lifetimes: Dyson orbitals and transition dipole moments

    NASA Astrophysics Data System (ADS)

    Jagau, Thomas-C.; Krylov, Anna I.

    2016-02-01

    The theoretical description of electronic resonances is extended beyond calculations of energies and lifetimes. We present the formalism for calculating Dyson orbitals and transition dipole moments within the equation-of-motion coupled-cluster singles and doubles method for electron-attached states augmented by a complex absorbing potential (CAP-EOM-EA-CCSD). The capabilities of the new methodology are illustrated by calculations of Dyson orbitals of various transient anions. We also present calculations of transition dipole moments between transient and stable anionic states as well as between different transient states. Dyson orbitals characterize the differences between the initial neutral and final electron-attached states without invoking the mean-field approximation. By extending the molecular-orbital description to correlated many-electron wave functions, they deliver qualitative insights into the character of resonance states. Dyson orbitals and transition moments are also needed for calculating experimental observables such as spectra and cross sections. Physically meaningful results for those quantities are obtained only in the framework of non-Hermitian quantum mechanics, e.g., in the presence of a complex absorbing potential (CAP), when studying resonances. We investigate the dependence of Dyson orbitals and transition moments on the CAP strength and illustrate how Dyson orbitals help understand the properties of metastable species and how they are affected by replacing the usual scalar product by the so-called c-product.

  10. Energy-management guidelines for rail-transit systems. Executive summary. Final report, 9 July 1984-30 October 1986

    SciTech Connect

    Uher, R.A.; Sharma, O.N.

    1986-09-01

    The cost of electricity is a significant portion of the operating costs of rail-transit systems. The impact of increasing energy costs is felt by those systems presently in operation and will be felt by those in the planning or construction phases. Concerned by rising energy costs, managers of several rail-transit authorities have established energy-management programs. The objectives of these programs are energy cost reduction and improved energy efficiency. Both goals enhance rail-transit productivity. As a rule, energy management can foster its largest payoff when it is initiated during the design and construction phase of a rail-transit system. The high dollar savings occur because low-energy-cost technology and operating practices can be engineered into the system at the outset. However, changes in technology and operations of present transit systems can also reduce the electric bill. Reduction of energy cost can be achieved through energy conservation, load management, and power-rate intervention. These guidelines describe the tools and methodologies for assessing energy-conservation strategies and power-rate-structure modifications.

  11. Test and Evaluation Metrics of Crew Decision-Making And Aircraft Attitude and Energy State Awareness

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Ellis, Kyle K. E.; Stephens, Chad L.

    2013-01-01

    NASA has established a technical challenge, under the Aviation Safety Program, Vehicle Systems Safety Technologies project, to improve crew decision-making and response in complex situations. The specific objective of this challenge is to develop data and technologies which may increase a pilot's (crew's) ability to avoid, detect, and recover from adverse events that could otherwise result in accidents/incidents. Within this technical challenge, a cooperative industry-government research program has been established to develop innovative flight deck-based counter-measures that can improve the crew's ability to avoid, detect, mitigate, and recover from unsafe loss-of-aircraft state awareness - specifically, the loss of attitude awareness (i.e., Spatial Disorientation, SD) or the loss-of-energy state awareness (LESA). A critical component of this research is to develop specific and quantifiable metrics which identify decision-making and the decision-making influences during simulation and flight testing. This paper reviews existing metrics and methods for SD testing and criteria for establishing visual dominance. The development of Crew State Monitoring technologies - eye tracking and other psychophysiological - are also discussed as well as emerging new metrics for identifying channelized attention and excessive pilot workload, both of which have been shown to contribute to SD/LESA accidents or incidents.

  12. Energy and environmental policy in a period of transition. Proceedings of the twenty-third annual Illinois energy conference

    SciTech Connect

    1995-12-31

    The Twenty-Third Annual Illinois Energy Conference entitled, ``Energy and Environmental Policy in a Period of Transition`` was held in Chicago, Illinois on November 20--21, 1995. The conference program explored how federal policy in energy and environment is changing and how these shifts will impact the economy of the Midwest. The conference was divided in four plenary sessions. Session 1 focused on the national policy scene where speakers discussed proposed legislation to change federal energy and environmental policy. Session 2 looked at the future structure of the energy industry, projecting the roles of natural gas, the electric utility industry, and independent power producers in the overall energy system of the 21st century. Session 3 examined current federal policy in research and development as a baseline for discussing the future role of government and industry in supporting research and development. In particular, it looked at the relationship between energy research and development and global competitiveness. Finally, Session 4 attempted to tie these issues together and consider the impact of national policy change on Illinois and the Midwest.

  13. Roles of Energy Dissipation in a Liquid-Solid Transition of Out-of-Equilibrium Systems

    NASA Astrophysics Data System (ADS)

    Komatsu, Yuta; Tanaka, Hajime

    2015-07-01

    Self-organization of active matter as well as driven granular matter in nonequilibrium dynamical states has attracted considerable attention not only from the fundamental and application viewpoints but also as a model to understand the occurrence of such phenomena in nature. These systems share common features originating from their intrinsically out-of-equilibrium nature, and how energy dissipation affects the state selection in such nonequilibrium states remains elusive. As a simple model system, we consider a nonequilibrium stationary state maintained by continuous energy input, relevant to industrial processing of granular materials by vibration and/or flow. More specifically, we experimentally study roles of dissipation in self-organization of a driven granular particle monolayer. We find that the introduction of strong inelasticity entirely changes the nature of the liquid-solid transition from two-step (nearly) continuous transitions (liquid-hexatic-solid) to a strongly discontinuous first-order-like one (liquid-solid), where the two phases with different effective temperatures can coexist, unlike thermal systems, under a balance between energy input and dissipation. Our finding indicates a pivotal role of energy dissipation and suggests a novel principle in the self-organization of systems far from equilibrium. A similar principle may apply to active matter, which is another important class of out-of-equilibrium systems. On noting that interaction forces in active matter, and particularly in living systems, are often nonconservative and dissipative, our finding may also shed new light on the state selection in these systems.

  14. Highly correlated systems. Excitation energies of first row transition metals Sc-Cu

    NASA Astrophysics Data System (ADS)

    Raghavachari, Krishnan; Trucks, Gary W.

    1989-07-01

    The low-lying dns2→dn+1s1 excitation energies of the first row transition metal atoms Sc-Cu are calculated using fourth-order M≂ller-Plesset perturbation theory (MP4) as well as quadratic configuration interaction (QCI) techniques with large spd and spdf basis sets. The MP4 method performs well for Sc-Mn but fails dramatically for Fe-Cu. In contrast, the QCI technique performs uniformly for all excitation energies with a mean deviation from experiment of only 0.14 eV after including relativistic corrections. f functions contribute 0.1-0.4 eV to the excitation energies for these systems. The highly correlated d10 state of the Ni atom is also considered in detail. The QCI technique obtains the d9s1→d10 splitting of the Ni atom with an error of only 0.13 eV. The results show that single-configuration Hartree-Fock based methods can be successful in calculating excitation energies of transition metal atoms.

  15. Transitions, cross sections and neutron binding energy in 186Re by Prompt Gamma Activation Analysis

    NASA Astrophysics Data System (ADS)

    Lerch, A. G.; Hurst, A. M.; Firestone, R. B.; Revay, Zs.; Szentmiklosi, L.; McHale, S. R.; McClory, J. W.; Detwiler, B.; Carroll, J. J.

    2014-03-01

    The nuclide 186Re possesses an isomer with 200,000 year half-life while its ground state has a half-life of 3.718 days. It is also odd-odd and well-deformed nucleus, so should exhibit a variety of other interesting nuclear-structure phenomena. However, the available nuclear data is rather sparse; for example, the energy of the isomer is only known to within + 7 keV and, with the exception of the J?=1- ground state, every proposed level is tentative in the ENSDF. Previously, Prompt Gamma Activation Analysis (PGAA) was utilized to study natRe with 186,188Re being produced via thermal neutron capture. Recently, an enriched 185Re target was irradiated by thermal neutrons at the Budapest Research Reactor to build on those results. Prompt (primary and secondary) and delayed gamma-ray transitions were measured with a large-volume, Compton-suppressed HPGe detector. Absolute cross sections for each gamma transition were deduced and corrected for self attenuation within the sample. Fifty-two primary gamma-ray transitions were newly identified and used to determine a revised value of the neutron binding energy. DICEBOX was used to simulate the decay scheme and the total radiative thermal neutron capture cross section was found to be 97+/-3 b Supported by DTRA (Detwiler) through HDTRA1-08-1-0014.

  16. Efficient dynamical correction of the transition state theory rate estimate for a flat energy barrier

    NASA Astrophysics Data System (ADS)

    Mökkönen, Harri; Ala-Nissila, Tapio; Jónsson, Hannes

    2016-09-01

    The recrossing correction to the transition state theory estimate of a thermal rate can be difficult to calculate when the energy barrier is flat. This problem arises, for example, in polymer escape if the polymer is long enough to stretch between the initial and final state energy wells while the polymer beads undergo diffusive motion back and forth over the barrier. We present an efficient method for evaluating the correction factor by constructing a sequence of hyperplanes starting at the transition state and calculating the probability that the system advances from one hyperplane to another towards the product. This is analogous to what is done in forward flux sampling except that there the hyperplane sequence starts at the initial state. The method is applied to the escape of polymers with up to 64 beads from a potential well. For high temperature, the results are compared with direct Langevin dynamics simulations as well as forward flux sampling and excellent agreement between the three rate estimates is found. The use of a sequence of hyperplanes in the evaluation of the recrossing correction speeds up the calculation by an order of magnitude as compared with the traditional approach. As the temperature is lowered, the direct Langevin dynamics simulations as well as the forward flux simulations become computationally too demanding, while the harmonic transition state theory estimate corrected for recrossings can be calculated without significant increase in the computational effort.

  17. Excitation energies, polarizabilities, multipole transition rates, and lifetimes of ions along the francium isoelectronic sequence

    SciTech Connect

    Safronova, U. I.; Johnson, W. R.; Safronova, M. S.

    2007-10-15

    Relativistic many-body perturbation theory is applied to study properties of ions of the francium isoelectronic sequence. Specifically, energies of the 7s, 7p, 6d, and 5f states of Fr-like ions with nuclear charges Z=87-100 are calculated through third order; reduced matrix elements, oscillator strengths, transition rates, and lifetimes are determined for 7s-7p, 7p-6d, and 6d-5f electric-dipole transitions; and 7s-6d, 7s-5f, and 5f{sub 5/2}-5f{sub 7/2} multipole matrix elements are evaluated to obtain the lifetimes of low-lying excited states. Moreover, for the ions Z=87-92 calculations are also carried out using the relativistic all-order single-double method, in which single and double excitations of Dirac-Fock wave functions are included to all orders in perturbation theory. With the aid of the single-double wave functions, we obtain accurate values of energies, transition rates, oscillator strengths, and the lifetimes of these six ions. Ground state scalar polarizabilities in Fr I, Ra II, Ac III, and Th IV are calculated using relativistic third-order and all-order methods. Ground state scalar polarizabilities for other Fr-like ions are calculated using a relativistic second-order method. These calculations provide a theoretical benchmark for comparison with experiment and theory.

  18. Efficient dynamical correction of the transition state theory rate estimate for a flat energy barrier.

    PubMed

    Mökkönen, Harri; Ala-Nissila, Tapio; Jónsson, Hannes

    2016-09-01

    The recrossing correction to the transition state theory estimate of a thermal rate can be difficult to calculate when the energy barrier is flat. This problem arises, for example, in polymer escape if the polymer is long enough to stretch between the initial and final state energy wells while the polymer beads undergo diffusive motion back and forth over the barrier. We present an efficient method for evaluating the correction factor by constructing a sequence of hyperplanes starting at the transition state and calculating the probability that the system advances from one hyperplane to another towards the product. This is analogous to what is done in forward flux sampling except that there the hyperplane sequence starts at the initial state. The method is applied to the escape of polymers with up to 64 beads from a potential well. For high temperature, the results are compared with direct Langevin dynamics simulations as well as forward flux sampling and excellent agreement between the three rate estimates is found. The use of a sequence of hyperplanes in the evaluation of the recrossing correction speeds up the calculation by an order of magnitude as compared with the traditional approach. As the temperature is lowered, the direct Langevin dynamics simulations as well as the forward flux simulations become computationally too demanding, while the harmonic transition state theory estimate corrected for recrossings can be calculated without significant increase in the computational effort. PMID:27609008

  19. Helping Students make the transition from novice learner of ground-water concepts to expert using the Plume Busters software

    USGS Publications Warehouse

    Macfarlane, P.A.; Bohling, G.; Thompson, K.W.; Townsend, M.

    2006-01-01

    Environmental and earth science students are novice learners and lack the experience needed to rise to the level of expert. To address this problem we have developed the prototype Plume Busters?? software as a capstone educational experience, in which students take on the role of an environmental consultant. Following a pipeline spill, the environmental consultant is hired by the pipeline owner to locate the resulting plume created by spill and remediate the contaminated aquifer at minimum monetary and time cost. The contamination must be removed from the aquifer before it reaches the river and eventually a downstream public water supply. The software consists of an interactive Java application and accompanying HTML linked pages. The application simulates movement of a plume from a pipeline break throug h a shallow alluvial aquifer towards the river. The accompanying web pages establish the simulated contamination scenario and provide students with background material on ground-water flow and transport principles. To make the role-play more realistic, the student must consider cost and time when making decisions about siting observation wells and wells for the pump-and-treat remediation system.

  20. Europe's battery: The making of the Alpine energy landscape, 1870-1955

    NASA Astrophysics Data System (ADS)

    Landry, Marc D., II

    iconic landscapes. It sheds light on the hydroelectric energy transition and shows the environmental impacts of electrification. Finally the history of Europe's Battery illuminates an alternative regional history of energy development and industrialization in Europe, one based on water and electricity and not coal.

  1. Wetting transition in liquid Ga Bi alloys: light scattering study of surface energy and entropy

    NASA Astrophysics Data System (ADS)

    Ayyad, A. H.; Freyland, W.

    2002-05-01

    We have studied the surface energy, surface entropy and, partly, have received an estimate of the viscosity of liquid Ga-Bi alloys at compositions mainly in the Ga-rich phase region and at temperatures up to 620 K. Measurements have been performed by the noninvasive method of capillary wave spectroscopy which has been applied for the first time to investigate the surface properties of a liquid alloy at high temperatures. Analysis of the concentration dependence of the surface energy according to the Gibbs adsorption equation yields that in the composition range of 10 -2≲ xBi≲10 -1 and at temperatures of 450 K≲ T≲500 K a surface excess of ΓBi˜1.36×10 -5 mol m -2 resides at the liquid-vapour interface corresponding to pure Bi. At lower xBi a reduction of ΓBi occurs which is indicative of a prewetting transition. The variations of surface energy and entropy with composition are not consistent with a description by a simple monolayer model as was deduced from X-ray reflectivity results. Instead it is found that a multilayer model qualitatively accounts for the characteristic change of the surface quantities. The thickness of the multilayer interfacial region is estimated from the change of the relative surface entropy. This yields values between 10 and 20 Å with a trend for an increasing number of surface layers towards the complete wetting transition at the monotectic point. All isopleths of the surface energy exhibit clear kinks at temperatures 10-20 K above the liquidus curve for compositions below the monotectic point. The corresponding discontinuity of the surface entropy is consistent with a first order transition of surface freezing reported recently for the Ga-Bi system.

  2. Energy levels, radiative rates, and lifetimes for transitions in W XL

    SciTech Connect

    Aggarwal, Kanti M. Keenan, Francis P.

    2014-11-15

    Energy levels and radiative rates are reported for transitions in Br-like tungsten, W XL, calculated with the general-purpose relativistic atomic structure package (GRASP). Configuration interaction (CI) has been included among 46 configurations (generating 4215 levels) over a wide energy range up to 213 Ryd. However, for conciseness results are only listed for the lowest 360 levels (with energies up to ∼43 Ryd), which mainly belong to the 4s{sup 2}4p{sup 5},4s{sup 2}4p{sup 4}4d,4s{sup 2}4p{sup 4}4f,4s4p{sup 6},4p{sup 6}4d,4s4p{sup 5}4d,4s{sup 2}4p{sup 3}4d{sup 2}, and 4s{sup 2}4p{sup 3}4d4f configurations, and provided for four types of transitions, E1, E2, M1, and M2. Comparisons are made with existing (but limited) results. However, to fully assess the accuracy of our data, analogous calculations have been performed with the flexible atomic code, including an even larger CI than in GRASP. Our energy levels are estimated to be accurate to better than 0.02 Ryd, whereas results for radiative rates (and lifetimes) should be accurate to better than 20% for a majority of the strong transitions.

  3. Energy levels, lifetimes, and transition probabilities for Mn XII and Ge XIX

    SciTech Connect

    El-Sayed, Fatma

    2014-09-15

    Energy levels, transition probabilities, oscillator strengths, line strengths, and lifetimes have been calculated for silicon-like manganese and germanium, Mn XII and Ge XIX. The configurations 3s{sup 2}3p{sup 2}, 3s3p{sup 3}, 3s{sup 2}3p3d, 3s3p{sup 2}3d, and 3p{sup 4} were used in the calculations and 88 fine-structure levels were obtained. The fully relativistic GRASP code has been adopted, and results are reported for all electric dipole, electric quadrupole, magnetic dipole, and magnetic quadrupole transitions among levels of Mn XII and Ge XIX. Comparisons have been made with available theoretical and experimental results.

  4. Theoretical study on K, L, and M X-ray transition energies and rates of neptunium and its ions

    NASA Astrophysics Data System (ADS)

    Ismail Abdalla, Saber; Dong, Chen-Zhong; Wang, Xiang-Li; Zhou, Wei-Dong; Wu, Zhong-Wen

    2014-02-01

    The transition energies and electric dipole (E1) transition rates of the K, L, and M lines in neutral Np have been theoretically determined from the MultiConfiguration Dirac—Fock (MCDF) method. In the calculations, the contributions from Breit interaction and quantum electrodynamics (QED) effects (vacuum polarization and self-energy), as well as nuclear finite mass and volume effects, are taken into account. The calculated transition energies and rates are found to be in good agreement with other experimental and theoretical results. The accuracy of the results is estimated and discussed. Furthermore, we calculated the transition energies of the same lines radiating from the decaying transitions of the K-, L-, and M-shell hole states of Np ions with the charge states Np1+ to Np6+ for the first time. We found that for a specific line, the corresponding transition energies relating to all the Np ions are almost the same; it means the outermost electrons have a very small influence on the inner-shell transition processes.

  5. Accurate nonrelativistic ground-state energies of 3d transition metal atoms

    SciTech Connect

    Scemama, A.; Applencourt, T.; Giner, E.; Caffarel, M.

    2014-12-28

    We present accurate nonrelativistic ground-state energies of the transition metal atoms of the 3d series calculated with Fixed-Node Diffusion Monte Carlo (FN-DMC). Selected multi-determinantal expansions obtained with the CIPSI (Configuration Interaction using a Perturbative Selection made Iteratively) method and including the most prominent determinants of the full configuration interaction expansion are used as trial wavefunctions. Using a maximum of a few tens of thousands determinants, fixed-node errors on total DMC energies are found to be greatly reduced for some atoms with respect to those obtained with Hartree-Fock nodes. To the best of our knowledge, the FN-DMC/(CIPSI nodes) ground-state energies presented here are the lowest variational total energies reported so far. They differ from the recently recommended non-variational values of McCarthy and Thakkar [J. Chem. Phys. 136, 054107 (2012)] only by a few percents of the correlation energy. Thanks to the variational property of FN-DMC total energies, our results provide exact lower bounds for the absolute value of all-electron correlation energies, |E{sub c}|.

  6. Energy balance in the solar transition region. I - Hydrostatic thermal models with ambipolar diffusion

    NASA Technical Reports Server (NTRS)

    Fontenla, J. M.; Avrett, E. H.; Loeser, R.

    1990-01-01

    The energy balance in the lower transition region is analyzed by constructing theoretical models which satisfy the energy balance constraint. The energy balance is achieved by balancing the radiative losses and the energy flowing downward from the corona. This energy flow is mainly in two forms: conductive heat flow and hydrogen ionization energy flow due to ambipolar diffusion. Hydrostatic equilibrium is assumed, and, in a first calculation, local mechanical heating and Joule heating are ignored. In a second model, some mechanical heating compatible with chromospheric energy-balance calculations is introduced. The models are computed for a partial non-LTE approach in which radiation departs strongly from LTE but particles depart from Maxwellian distributions only to first order. The results, which apply to cases where the magnetic field is either absent, or uniform and vertical, are compared with the observed Lyman lines and continuum from the average quiet sun. The approximate agreement suggests that this type of model can roughly explain the observed intensities in a physically meaningful way, assuming only a few free parameters specified as chromospheric boundary conditions.

  7. Alternative fuel transit buses

    SciTech Connect

    Motta, R.; Norton, P.; Kelly, K.

    1996-10-01

    The National Renewable Energy Laboratory (NREL) is a U.S. Department of Energy (DOE) national laboratory; this project was funded by DOE. One of NREL`s missions is to objectively evaluate the performance, emissions, and operating costs of alternative fuel vehicles so fleet managers can make informed decisions when purchasing them. Alternative fuels have made greater inroads into the transit bus market than into any other. Each year, the American Public Transit Association (APTA) surveys its members on their inventory and buying plans. The latest APTA data show that about 4% of the 50,000 transit buses in its survey run on an alternative fuel. Furthermore, 1 in 5 of the new transit buses that members have on order are alternative fuel buses. This program was designed to comprehensively and objectively evaluate the alternative fuels in use in the industry.

  8. Variational Calculations of Ro-Vibrational Energy Levels and Transition Intensities for Tetratomic Molecules

    NASA Technical Reports Server (NTRS)

    Schwenke, David W.; Langhoff, Stephen R. (Technical Monitor)

    1995-01-01

    A description is given of an algorithm for computing ro-vibrational energy levels for tetratomic molecules. The expressions required for evaluating transition intensities are also given. The variational principle is used to determine the energy levels and the kinetic energy operator is simple and evaluated exactly. The computational procedure is split up into the determination of one dimensional radial basis functions, the computation of a contracted rotational-bending basis, followed by a final variational step coupling all degrees of freedom. An angular basis is proposed whereby the rotational-bending contraction takes place in three steps. Angular matrix elements of the potential are evaluated by expansion in terms of a suitable basis and the angular integrals are given in a factorized form which simplifies their evaluation. The basis functions in the final variational step have the full permutation symmetries of the identical particles. Sample results are given for HCCH and BH3.

  9. Reorganization energy of electron transfer in viscous solvents above the glass transition.

    PubMed

    Ghorai, Pradip K; Matyushov, Dmitry V

    2006-02-01

    We present a molecular-dynamics study of the solvent reorganization energy of electron transfer in supercooled water. We observe a sharp decrease of the reorganization energy at a temperature identified as the temperature of structural arrest due to cage effect as discussed by the mode coupling theory. Both the heat capacity and dielectric susceptibility of the pure water show sharp drops at about the same temperature. This temperature also marks the onset of the enhancement of translational diffusion relative to rotational relaxation signaling the breakdown of the Stokes-Einstein relation. The change in the reorganization energy at the transition temperature reflects the dynamical arrest of the slow, collective relaxation of the solvent related to Debye relaxation of the solvent dipolar polarization.

  10. Surface energy exchanges along a tundra-forest transition and feedbacks to climate

    USGS Publications Warehouse

    Beringer, J.; Chapin, F. S.; Thompson, Catharine Copass; McGuire, A.D.

    2005-01-01

    Surface energy exchanges were measured in a sequence of five sites representing the major vegetation types in the transition from arctic tundra to forest. This is the major transition in vegetation structure in northern high latitudes. We examined the influence of vegetation structure on the rates of sensible heating and evapotranspiration to assess the potential feedbacks to climate if high-latitude warming were to change the distribution of these vegetation types. Measurements were made at Council on the Seward Peninsula, Alaska, at representative tundra, low shrub, tall shrub, woodland (treeline), and boreal forest sites. Structural differences across the transition from tundra to forest included an increase in the leaf area index (LAI) from 0.52 to 2.76, an increase in canopy height from 0.1 to 6.1 m, and a general increase in canopy complexity. These changes in vegetation structure resulted in a decrease in albedo from 0.19 to 0.10 as well as changes to the partitioning of energy at the surface. Bulk surface resistance to water vapor flux remained virtually constant across sites, apparently because the combined soil and moss evaporation decreased while transpiration increased along the transect from tundra to forest. In general, sites became relatively warmer and drier along the transect with the convective fluxes being increasingly dominated by sensible heating, as evident by an increasing Bowen ratio from 0.94 to 1.22. The difference in growing season average daily sensible heating between tundra and forest was 21 W m-2. Fluxes changed non-linearly along the transition, with both shrubs and trees substantially enhancing heat transfer to the atmosphere. These changes in vegetation structure that increase sensible heating could feed back to enhance warming at local to regional scales. The magnitude of these vegetation effects on potential high-latitude warming is two to three times greater than suggested by previous modeling studies. ?? 2005 Elsevier B.V. All

  11. Energy Budget Changes Impact Arid Mountain Hydrology More Than Rain-Snow Transitions

    NASA Astrophysics Data System (ADS)

    Foster, L.; Maxwell, R. M.; Bearup, L. A.; Molotch, N. P.; Brooks, P. D.

    2015-12-01

    Temperature increases due to climate change will alter two main drivers of hydrology, energy and moisture, by reducing the fraction of precipitation falling as snow, as well as impacting the land surface energy budget. Recent hydrological work has studied the impacts of these two drivers using statistical analysis of basins with different average precipitation and climate as proxies for moisture and energy changes, however, very few studies have used modeling to explicitly separate energy budget changes from snow to rain transitions. Integrated models provide an opportunity to isolate these effects of climate change from natural interannual variability, the latter of which are difficult to tease out in field and statistical studies. Given that much of the world depends on mountain snowpack for their water supply, understanding hydrologic sensitivity to variability in phase and amount of precipitation, temperature and runoff in complex terrain is imperative. This study uses an integrated hydrologic model, Parflow, fully coupled to the Common Land Model, to investigate a hypothetical, vegetated mountain hillslope response to energy budget and precipitation phase changes due to warming. In our simulations, year round warming scenarios decreased mean streamflow by approximately 20%, contrary to shifts from snow to rain which in some scenarios exhibited a small increase in streamflow, indicating that energy budget is the main driver of total mean streamflow. Seasonal warming impacted the volume of peak runoff, with winter and transitional (fall&spring) warming increasing peak runoff by more than 15%, suggesting that interannual variation in temperature may aid in flood risk calculations. This modeling framework can be applied in other regions to provide context and points of comparison for existing observational and statistical studies of climate change impacts on hydrology.

  12. Thermodynamic free energy methods to investigate shape transitions in bilayer membranes

    PubMed Central

    Ramakrishnan, N.; Tourdot, Richard W.

    2016-01-01

    The conformational free energy landscape of a system is a fundamental thermodynamic quantity of importance particularly in the study of soft matter and biological systems, in which the entropic contributions play a dominant role. While computational methods to delineate the free energy landscape are routinely used to analyze the relative stability of conformational states, to determine phase boundaries, and to compute ligand-receptor binding energies its use in problems involving the cell membrane is limited. Here, we present an overview of four different free energy methods to study morphological transitions in bilayer membranes, induced either by the action of curvature remodeling proteins or due to the application of external forces. Using a triangulated surface as a model for the cell membrane and using the framework of dynamical triangulation Monte Carlo, we have focused on the methods of Widom insertion, thermodynamic integration, Bennett acceptance scheme, and umbrella sampling and weighted histogram analysis. We have demonstrated how these methods can be employed in a variety of problems involving the cell membrane. Specifically, we have shown that the chemical potential, computed using Widom insertion, and the relative free energies, computed using thermodynamic integration and Bennett acceptance method, are excellent measures to study the transition from curvature sensing to curvature inducing behavior of membrane associated proteins. The umbrella sampling and WHAM analysis has been used to study the thermodynamics of tether formation in cell membranes and the quantitative predictions of the computational model are in excellent agreement with experimental measurements. Furthermore, we also present a method based on WHAM and thermodynamic integration to handle problems related to end-point-catastrophe that are common in most free energy methods.

  13. IBS and Potential Luminosity Improvement for RHIC Operation Below Transition Energy

    SciTech Connect

    Fedotov,A.

    2009-01-02

    There is a strong interest in low-energy RHIC operations in the single-beam total energy range of 2.5-25 GeV/nucleon [1-3]. Collisions in this energy range, much of which is below nominal RHIC injection energy, will help to answer one of the key questions in the field of QeD about the existence and location of a critical point on the QCD phase diagram [4]. There have been several short test runs during 2006-2008 RHIC operations to evaluate RHIC operational challenges at these low energies [5]. Beam lifetimes observed during the test runs were limited by machine nonlinearities. This performance limit can be improved with sufficient machine tuning. The next luminosity limitation comes from transverse and longitudinal Intra-beam Scattering (IBS), and ultimately from the space-charge limit. Detailed discussion of limiting beam dynamics effects and possible luminosity improvement with electron cooling can be found in Refs. [6-8]. For low-energy RHIC operation, particle losses from the RF bucket are of particular concern since the longitudinal beam size is comparable to the existing RF bucket at low energies. However, operation below transition energy allows us to exploit an Intra-beam Scattering (IBS) feature that drives the transverse and longitudinal beam temperatures towards equilibrium by minimizing the longitudinal diffusion rate using a high RF voltage. Simulation studies were performed with the goal to understand whether one can use this feature of IBS to improve luminosity of RHIC collider at low-energies. This Note presents results of simulations which show that additional luminosity improvement for low-energy RHIC project may be possible with high RF voltage from a 56 MHz superconducting RF cavity that is presently under development for RHIC.

  14. Energy Transition Initiative: Island Energy Snapshot - Saint Martin/Sint Maarten

    SciTech Connect

    2015-09-01

    This profile provides a snapshot of the energy landscape of the northeast Caribbean island Saint Martin. The island is divided between two nations, France in the north (Saint-Martin) and the Netherlands in the south (Sint Maarten).

  15. Shape of the absorption and fluorescence spectra of condensed phases and transition energies.

    PubMed

    Lagos, Miguel; Paredes, Rodrigo

    2014-11-13

    General integral expressions for the temperature-dependent profile of the spectral lines of photon absorption and emission by atomic or molecular species in a condensed environment are derived with no other hypothesis than: (a) The acoustic vibrational modes of the condensed host medium constitute the thermodynamic energy reservoir at a given constant temperature, and local electronic transitions modifying the equilibrium configuration of the surroundings are multiphonon events, regardless of the magnitude of the transition energy. (b) Electron-phonon coupling is linear in the variations of the bond length. The purpose is to develop a theoretical tool for the analysis of the spectra, allowing us to grasp highly accurate information from fitting the theoretical line shape function to experiment, including those spectra displaying wide features. The method is illustrated by applying it to two dyes, Lucifer Yellow CH and Coumarin 1, which display fluorescence maxima of 0.41 and 0.51 eV fwhm. Fitting the theoretical curves to the spectra indicates that the neat excitation energies are 2.58 eV ± 2.5% and 3.00 eV ± 2.0%, respectively.

  16. Europe in the energy transition: the case for a smaller population.

    PubMed

    Grant, L

    1988-07-01

    Europe has not yet reached a sustainable society, that is, like the rest of the world, its people cannot live comfortably within its resources, but, it has achieved stabilizing population growth, a control on a potentially dangerous dependency on imported food, an adjustment to the transition from the colonial era, and a position conducive to deal with the energy transition. Europe is the most densely population region of the world, except for Japan. Concern about depopulation in western Europe is misplaced because European populations are on a plateau not a decline, and a lower population is a benefit when confronting resource and environmental constraints. World oil production is expected to peak and then to decline depending on demand, prices, and technology. European oil production will decline, and the United Kingdom will become a net importer in the mid-1990s. The environmental transition is described as more complex than finding a substitute for oil, in part because Europe, unlike the US, has limited fossil fuel resources which are also less accessible. Biomass as the alternative to fossil fuels must be produced on lands currently in food or forestry production. Also corn and bagasse production is not suited to for growing the European climate. Nuclear energy, with its safety and disposal problems, is only an interim solution. Hydropower development is expensive, and solar power is unsuitable because of the continual cloud cover. Wind power is possible but expensive at low wind levels, and the whole of western Europe is relatively unsuitable. Capital creates wealth, and unemployment is Europe's present problem. Large populations in the current technological revolution do not create greater wealth or military security. Europe and Japan have arrived at the population/energy/environment problem first, and many questions remain as to how to manage the age structure, how to maintain innovation and creativity, and how to maintain a prosperous steady state economy

  17. Europe in the energy transition: the case for a smaller population.

    PubMed

    Grant, L

    1988-07-01

    Europe has not yet reached a sustainable society, that is, like the rest of the world, its people cannot live comfortably within its resources, but, it has achieved stabilizing population growth, a control on a potentially dangerous dependency on imported food, an adjustment to the transition from the colonial era, and a position conducive to deal with the energy transition. Europe is the most densely population region of the world, except for Japan. Concern about depopulation in western Europe is misplaced because European populations are on a plateau not a decline, and a lower population is a benefit when confronting resource and environmental constraints. World oil production is expected to peak and then to decline depending on demand, prices, and technology. European oil production will decline, and the United Kingdom will become a net importer in the mid-1990s. The environmental transition is described as more complex than finding a substitute for oil, in part because Europe, unlike the US, has limited fossil fuel resources which are also less accessible. Biomass as the alternative to fossil fuels must be produced on lands currently in food or forestry production. Also corn and bagasse production is not suited to for growing the European climate. Nuclear energy, with its safety and disposal problems, is only an interim solution. Hydropower development is expensive, and solar power is unsuitable because of the continual cloud cover. Wind power is possible but expensive at low wind levels, and the whole of western Europe is relatively unsuitable. Capital creates wealth, and unemployment is Europe's present problem. Large populations in the current technological revolution do not create greater wealth or military security. Europe and Japan have arrived at the population/energy/environment problem first, and many questions remain as to how to manage the age structure, how to maintain innovation and creativity, and how to maintain a prosperous steady state economy.

  18. ENERGY CONVERSION FOR THE TRANSITION FROM Al TO γ-Al2O3 NANOPARTICLES

    NASA Astrophysics Data System (ADS)

    Wang, Shulin; Li, Shengjuan; Xu, Bo; Jian, Dunliang; Zhu, Yufang

    2013-07-01

    We have successfully converted large volume Al particles into γ-Al2O3 nanostructures by vibration milling at room temperature and successive treatment. We show that there exist special relationships among stacking fault energy (SFE), strain energy (SRE), and surface energy (SE) of the materials, including interdependence, intercompetition, and interconversion during the phase transition. SFE and SRE perform the same changing tendency, while SE just does the opposite. However, it is not the particle size but the energy state that determines the reactivity of the materials. And it is the SE that can directly determine the physical chemical reaction and the conversion into the end product rather than SFE and SRE. When SE goes up, the material reactivity and the product yield will be enhanced; and when SE goes down, the reaction and the product yield will decay. However, the state of SE depends closely on the change tendency of the SFE and SRE. That is, when SFE and SRE goes up, SE will goes down; if SFE and SRE goes down, SE will goes up. It seems that energy conservation law may be followed in a sense in the particle system if the external input keeps constant. The work may be significant for energy conversion in nano-scale and mechanosynthesis of oxide nanoparticles.

  19. Transition from IVR limited vibrational energy transport to bulk heat transport

    NASA Astrophysics Data System (ADS)

    Schade, Marco; Hamm, Peter

    2012-01-01

    In a previous paper [M. Schade, P. Hamm, Vibrational energy transport in the presence of intrasite vibrational energy redistribution, J. Chem. Phys. 131 (2009) 044511], it has been shown that on ultrashort length and time scales, the speed of vibrational energy transport along a molecular chain is limited by intrasite vibrational relaxation rather than the actual intersite propagation. However, since intrasite vibrational relaxation is length independent, the intersite propagation rate is expected to become rate-limiting at some length scale, where propagation approaches the bulk limit. In the present paper, we investigate the transition between both regimes. The response of different types of modes may be very different at early times, depending on how much they contribute directly to energy transport. Surprisingly though, when averaging the energy content over all vibrational modes of the various chain sites, the complexity of the intrasite vibrational relaxation process is completely hidden so that energy transport on the nanoscale can be described by an effective propagation rate, that equals the bulk value, even at short times.

  20. Making Clean Energy with a Kerr Black Hole: A Tokamak Model for Gamma-Ray Bursts

    NASA Astrophysics Data System (ADS)

    Li, Li-Xin

    2000-11-01

    In this paper we present a model for making clean energy with a Kerr black hole. Consider a Kerr black hole with a dense plasma torus spinning around it. A toroidal electric current flows on the surface of the torus, which generates a poloidal magnetic field outside the torus. On the surface of the torus the magnetic field is parallel to the surface. The closed magnetic field lines winding around the torus compress and confine the plasma in the torus, as in the case of tokamaks. Although it is unclear whether such a model is stable, we look into the consequences if the model is stable. If the magnetic field is strong enough, the baryonic contamination from the plasma in the torus is greatly suppressed by the magnetic confinement, and a clean magnetosphere of electron-positron pairs is built up around the black hole. Since there are no open magnetic field lines threading the torus and no accretion, the power of the torus is zero. If some magnetic field lines threading the black hole are open and connect with loads, clean energy can be extracted from the Kerr black hole by the Blandford-Znajek mechanism. The model may be relevant to gamma-ray bursts. The energy in the Poynting flux produced by the Blandford-Znajek mechanism is converted into the kinetic energy of the electron-positron pairs in the magnetosphere around the black hole, which generates two oppositely directed jets of electron-positron pairs with superhigh bulk Lorentz factors. The jets collide and interact with the interstellar medium, which may produce gamma-ray bursts and the afterglows.

  1. Level Energies, Oscillator Strengths and Lifetimes for Transitions in Pb IV

    SciTech Connect

    Colon, C.; Alonso-Medina, A.; Zanon, A.; Albeniz, J.

    2008-10-22

    Oscillator strengths for several lines of astrophysical interest arising from some configurations and some levels radiative lifetimes of Pb IV have been calculated. These values were obtained in intermediate coupling (IC) and using ab initio relativistic Hartree-Fock calculations. We use for the IC calculations the standard method of least square fitting of experimental energy levels by means of computer codes from Cowan. Transition Probabilities and oscillator strengths obtained, although in general agreement with the rare experimental data, do present some noticeable discrepancies that are studied in the text.

  2. MACHETE: A transit imaging atmospheric Cherenkov telescope to survey half of the very high energy γ-ray sky

    NASA Astrophysics Data System (ADS)

    Cortina, J.; López-Coto, R.; Moralejo, A.

    2016-01-01

    Current imaging atmospheric Cherenkov telescopes for very high energy γ-ray astrophysics are pointing instruments with a field of view up to a few tens of sq deg. We propose to build an array of two non-steerable (drift) telescopes. Each of the telescopes would have a camera with a FOV of 5 × 60 sq deg oriented along the meridian. About half of the sky drifts through this FOV in a year. We have performed a Monte Carlo simulation to estimate the performance of this instrument. We expect it to survey this half of the sky with an integral flux sensitivity of ˜0.77% of the steady flux of the Crab Nebula in 5 years, an analysis energy threshold of ˜150 GeV and an angular resolution of ˜0.1°. For astronomical objects that transit over the telescope for a specific night, we can achieve an integral sensitivity of 12% of the Crab Nebula flux in a night, making it a very powerful tool to trigger further observations of variable sources using steerable IACTs or instruments at other wavelengths.

  3. Energy levels and radiative rates for transitions in Mg-like iron, cobalt and nickel

    SciTech Connect

    Aggarwal, K.M. . E-mail: k.aggarwal@qub.ac.uk; Tayal, Vikas; Gupta, G.P.; Keenan, F.P.

    2007-09-15

    Energy levels and radiative rates for electric dipole (E1) transitions among the lowest 141 levels of the (1s{sup 2}2s{sup 2}2p{sup 6}) 3l{sup 2}, 3l3l', and 3l4l configurations of Fe XV, Co XVI, and Ni XVII are calculated through the CIV3 code using extensive configuration-interaction (CI) wavefunctions. The important relativistic effects are included through the Breit-Pauli approximation. In order to keep the calculated energy splittings close to the experimental values, we have made small adjustments to the diagonal elements of the Hamiltonian matrices. The energy levels, including their orderings, are in excellent agreement with the available experimental results for all three ions. However, experimental energies are only available for a few levels. Since mixing among some levels is found to be very strong, it becomes difficult to identify these uniquely. Additionally, some discrepancies with other theoretical work (particularly for Ni XVII) are very large. Therefore, in order to confirm the level ordering as well as to assess the accuracy of energy levels and radiative rates, we have performed two other independent calculations using the GRASP and FAC codes. These codes are fully relativistic, but the CI in the calculations is limited to the basic (minimum) configurations only. This enables us to assess the importance of including elaborate CI for moderately charged ions. Additionally, we report results for electric quadrupole (E2), magnetic dipole (M1), and magnetic quadrupole (M2) transitions, and list lifetimes for all levels. Comparisons are made with other available experimental and theoretical results, and the accuracy of the present results is assessed.

  4. Dynamics of driven transitions between minima of a complex energy landscapes

    NASA Astrophysics Data System (ADS)

    Pusuluri, Sai Teja; Lang, Alex H.; Mehta, Pankaj; Castillo, Horacio E.

    We recently modeled cellular interconvertion dynamics by using an epigenetic landscape model inspired by neural network models. Given an arbitrary set of patterns, the model can be used to construct an energy landscape in which those patterns are the global minima. Here we study the transitions between stable states of the landscapes thus constructed, under the effect of an external driving force. We consider three different cases: i) choosing the patterns to be random and independendently distributed ii) choosing a set of patterns directly derived from the experimental cellular transcription factor expression data for a representative set of cell types in an organism and iii) choosing randomly generated trees of hierarchically correlated patterns, inspired by biology. For each of the three cases, we study the stability of the global minima against thermal fluctuations and external driving forces, and the dynamics of the driven transitions away from global minima. We compare the results obtained in the three cases defined above, and in particular we explore to what degree the correlations between patterns affect the transition dynamics.

  5. Spin-glass phase transitions and minimum energy of the random feedback vertex set problem

    NASA Astrophysics Data System (ADS)

    Qin, Shao-Meng; Zeng, Ying; Zhou, Hai-Jun

    2016-08-01

    A feedback vertex set (FVS) of an undirected graph contains vertices from every cycle of this graph. Constructing a FVS of sufficiently small cardinality is very difficult in the worst cases, but for random graphs this problem can be efficiently solved by converting it into an appropriate spin-glass model [H.-J. Zhou, Eur. Phys. J. B 86, 455 (2013), 10.1140/epjb/e2013-40690-1]. In the present work we study the spin-glass phase transitions and the minimum energy density of the random FVS problem by the first-step replica-symmetry-breaking (1RSB) mean-field theory. For both regular random graphs and Erdös-Rényi graphs, we determine the inverse temperature βl at which the replica-symmetric mean-field theory loses its local stability, the inverse temperature βd of the dynamical (clustering) phase transition, and the inverse temperature βs of the static (condensation) phase transition. These critical inverse temperatures all change with the mean vertex degree in a nonmonotonic way, and βd is distinct from βs for regular random graphs of vertex degrees K >60 , while βd are identical to βs for Erdös-Rényi graphs at least up to mean vertex degree c =512 . We then derive the zero-temperature limit of the 1RSB theory and use it to compute the minimum FVS cardinality.

  6. Periodic inversion and phase transition of finite energy Airy beams in a medium with parabolic potential.

    PubMed

    Zhang, Yiqi; Belić, Milivoj R; Zhang, Lei; Zhong, Weiping; Zhu, Dayu; Wang, Ruimin; Zhang, Yanpeng

    2015-04-20

    We study periodic inversion and phase transition of normal, displaced, and chirped finite energy Airy beams propagating in a parabolic potential. This propagation leads to an unusual oscillation: for half of the oscillation period the Airy beam accelerates in one transverse direction, with the main Airy beam lobe leading the train of pulses, whereas in the other half of the period it accelerates in the opposite direction, with the main lobe still leading - but now the whole beam is inverted. The inversion happens at a critical point, at which the beam profile changes from an Airy profile to a Gaussian one. Thus, there are two distinct phases in the propagation of an Airy beam in the parabolic potential - the normal Airy and the single-peak Gaussian phase. The length of the single-peak phase is determined by the size of the decay parameter: the smaller the decay, the smaller the length. A linear chirp introduces a transverse displacement of the beam at the phase transition point, but does not change the location of the point. A quadratic chirp moves the phase transition point, but does not affect the beam profile. The two-dimensional case is discussed briefly, being equivalent to a product of two one-dimensional cases.

  7. Spin-glass phase transitions and minimum energy of the random feedback vertex set problem.

    PubMed

    Qin, Shao-Meng; Zeng, Ying; Zhou, Hai-Jun

    2016-08-01

    A feedback vertex set (FVS) of an undirected graph contains vertices from every cycle of this graph. Constructing a FVS of sufficiently small cardinality is very difficult in the worst cases, but for random graphs this problem can be efficiently solved by converting it into an appropriate spin-glass model [H.-J. Zhou, Eur. Phys. J. B 86, 455 (2013)EPJBFY1434-602810.1140/epjb/e2013-40690-1]. In the present work we study the spin-glass phase transitions and the minimum energy density of the random FVS problem by the first-step replica-symmetry-breaking (1RSB) mean-field theory. For both regular random graphs and Erdös-Rényi graphs, we determine the inverse temperature β_{l} at which the replica-symmetric mean-field theory loses its local stability, the inverse temperature β_{d} of the dynamical (clustering) phase transition, and the inverse temperature β_{s} of the static (condensation) phase transition. These critical inverse temperatures all change with the mean vertex degree in a nonmonotonic way, and β_{d} is distinct from β_{s} for regular random graphs of vertex degrees K>60, while β_{d} are identical to β_{s} for Erdös-Rényi graphs at least up to mean vertex degree c=512. We then derive the zero-temperature limit of the 1RSB theory and use it to compute the minimum FVS cardinality. PMID:27627285

  8. Impact of the symmetry energy on nuclear pasta phases and crust-core transition in neutron stars

    NASA Astrophysics Data System (ADS)

    Bao, S. S.; Shen, H.

    2015-01-01

    We study the impact of the symmetry energy on properties of nuclear pasta phases and crust-core transition in neutron stars. We perform a self-consistent Thomas-Fermi calculation employing the relativistic mean-field model. The properties of pasta phases presented in the inner crust of neutron stars are investigated and the crust-core transition is examined. It is found that the slope of the symmetry energy plays an important role in determining the pasta phase structure and the crust-core transition. The correlation between the symmetry energy slope and the crust-core transition density obtained in the Thomas-Fermi approximation is consistent with that predicted by the liquid-drop model.

  9. Accelerate the transition of radioisotopes or unwanted weapons-grade ^239Pu into stable nuclei with a system of high frequency modulation for a net energy gain

    NASA Astrophysics Data System (ADS)

    Pamfiloff, Eugene

    2006-10-01

    A process of high frequency stimulation of nucleons can be utilized for the accelerated fission, decay or controlled transition of unstable isotopes. For example ^238U could be persuaded to transition promptly into ^206Pb, where portions of the total mass difference of 29873.802 MeV per nucleus becomes available energy. The proposals of this paper describe an effective system for nuclei stimulation configured to accelerate such a series of 14 transitions over several milliseconds, instead of 4.47 x 10^9 years. Positive ions or ionized capsules of fuel suspended by magnetic fields and subjected to the system of correlated frequency modulation of multiple beam lines, tailored to the specific target, will emit sufficient energy to stimulate subsequent targets. The system can be applied to all radioisotopes, including ^232Th, nuclear waste product isotopes such as ^239Pu, and a variety of other suitable unstable or stable nuclei. Through the proposed confinement system and application of high frequency stimulation in the 10^22 to 10^24 Hz regime, the change in rest mass can be applied to both the fragmentation of subsequent, periodically injected targets, and the production of heat, making a continuous supply of energy possible. The system allows the particle fragmentation process to be brought into the laboratory and provides potential solutions to the safe disposal of fissile material.

  10. Accelerate the transition of radioisotopes and unwanted weapons-grade ^239Pu into stable nuclei with a system of high frequency modulation for a net energy gain

    NASA Astrophysics Data System (ADS)

    Pamfiloff, Eugene

    2006-10-01

    A process of high frequency stimulation of nucleons can be utilized for the accelerated fission, decay or controlled transition of unstable isotopes. ^238U could be persuaded to transition promptly into the stable ^206Pb isotope, where a portion of the total mass difference of 29873.802 MeV per nucleus becomes available energy. The proposals of this paper describe an effective system for nuclei stimulation configured to accelerate such a series of 14 transitions over several milliseconds, instead of 4.47 x 10^9 years. Positive ions or ionized capsules of fuel suspended by magnetic fields and subjected to the system of correlated frequency modulation of multiple beam lines, tailored to the specific target, will emit sufficient energy to stimulate subsequent targets. The system can be applied to all radioisotopes, nuclear waste product isotopes such as ^239Pu, and a variety of other suitable unstable or stable nuclei. Through the proposed confinement system and application of high frequency stimulation in the 10^22 to 10^24 Hz regime, the change in mass can be applied to both the fragmentation of subsequent, periodically injected targets, and the production of heat, making a continuous supply of energy possible. The system allows the particle fragmentation process to be brought into the lab and provides potential solutions to the safe disposal of fissile material.

  11. Accelerate the transition of radioisotopes and unwanted weapons-grade ^239Pu into stable nuclei with a system of high frequency modulation for a net energy gain

    NASA Astrophysics Data System (ADS)

    Pamfiloff, Eugene

    2006-11-01

    A process of high frequency stimulation of nucleons can be utilized for the accelerated fission, decay or controlled transition of unstable isotopes. ^238U could be persuaded to transition promptly into the stable ^206Pb isotope, where a portion of the total mass difference of 29873.802 MeV per nucleus becomes available energy. The proposals of this paper describe an effective system for nuclei stimulation configured to accelerate such a series of 14 transitions over several milliseconds, instead of 4.47 x 10^9 years. Positive ions or ionized capsules of fuel suspended by magnetic fields and subjected to the system of correlated frequency modulation of multiple beam lines, tailored to the specific target, will emit sufficient energy to stimulate subsequent targets. The system can be applied to all radioisotopes, nuclear waste product isotopes such as ^239Pu, and a variety of other suitable unstable or stable nuclei. Through the proposed confinement system and application of high frequency stimulation in the 10^22 to 10^24 Hz regime, the change in mass can be applied to both the fragmentation of subsequent, periodically injected targets, and the production of heat, making a continuous supply of energy possible. The system allows the particle fragmentation process to be brought into the lab and provides potential solutions to the safe disposal of fissile material.

  12. Making FLASH an Open Code for the Academic High-Energy Density Physics Community

    NASA Astrophysics Data System (ADS)

    Lamb, D. Q.; Couch, S. M.; Dubey, A.; Gopal, S.; Graziani, C.; Lee, D.; Weide, K.; Xia, G.

    2010-11-01

    High-energy density physics (HEDP) is an active and growing field of research. DOE has recently decided to make FLASH a code for the academic HEDP community. FLASH is a modular and extensible compressible spatially adaptive hydrodynamics code that incorporates capabilities for a broad range of physical processes, performs well on a wide range of existing advanced computer architectures, and has a broad user base. A rigorous software maintenance process allows the code to operate simultaneously in production and development modes. We summarize the work we are doing to add HEDP capabilities to FLASH. We are adding (1) Spitzer conductivity, (2) super time-stepping to handle the disparity between diffusion and advection time scales, and (3) a description of electrons, ions, and radiation (in the diffusion approximation) by 3 temperatures (3T) to both the hydrodynamics and the MHD solvers. We are also adding (4) ray tracing, (5) laser energy deposition, and (6) a multi-species equation of state incorporating ionization to the hydrodynamics solver; and (7) Hall MHD, and (8) the Biermann battery term to the MHD solver.

  13. A Cumulative Energy Demand indicator (CED), life cycle based, for industrial waste management decision making

    SciTech Connect

    Puig, Rita; Fullana-i-Palmer, Pere; Bala, Alba

    2013-12-15

    Highlights: • We developed a methodology useful to environmentally compare industrial waste management options. • The methodology uses a Net Energy Demand indicator which is life cycle based. • The method was simplified to be widely used, thus avoiding cost driven decisions. • This methodology is useful for governments to promote the best environmental options. • This methodology can be widely used by other countries or regions around the world. - Abstract: Life cycle thinking is a good approach to be used for environmental decision-support, although the complexity of the Life Cycle Assessment (LCA) studies sometimes prevents their wide use. The purpose of this paper is to show how LCA methodology can be simplified to be more useful for certain applications. In order to improve waste management in Catalonia (Spain), a Cumulative Energy Demand indicator (LCA-based) has been used to obtain four mathematical models to help the government in the decision of preventing or allowing a specific waste from going out of the borders. The conceptual equations and all the subsequent developments and assumptions made to obtain the simplified models are presented. One of the four models is discussed in detail, presenting the final simplified equation to be subsequently used by the government in decision making. The resulting model has been found to be scientifically robust, simple to implement and, above all, fulfilling its purpose: the limitation of waste transport out of Catalonia unless the waste recovery operations are significantly better and justify this transport.

  14. Negotiating Northern Resource Development Frontiers: People, Energy, and Decision-Making in Yamal

    NASA Astrophysics Data System (ADS)

    Osipov, Igor A.

    This dissertation examines contemporary models of co-existence and partnerships negotiated between local communities, government, and resource corporations in the Russian District of Purovsky (Arctic Yamal), with a particular focus on the relations of these partnerships to Russia's wider socio-cultural and political contexts and, more broadly, the circumpolar world. Yamal has Eurasia's richest oil and gas reserves, and is an important crossroads region where various geopolitical and financial interests intersect. With the opening up of new gas and oil fields, and construction of roads and pipelines, Yamal is experiencing rapid changes; and is being challenged to reshape its many 'frontiers' in which people, energy, and decisions are closely linked to one another. Since the late 1970s, resource development projects have had significant impacts on the lives of the local people in the Purovsky tundra. Along with experiencing negative consequences, such as water and soil contamination, impacts on land, wildlife, and local communities have also nurtured creative ways of adaptation, decision-making, and self-organization. Since 1998, a number of unique models of co-existence and participatory dialogue, involving public project reviews, and sound participation of local indigenous activist groups have been developed and implemented in Yamal. Furthermore, during the past decade the Purovsky District has served as a unique decision-making polygon for the Northeastern Urals. Several joint community-industry-government political and economic cooperation models have been tested and their elements have subsequently been implemented in other Arctic Russian localities. From 2006-2008 this project was focused on documenting these important developments by investigating and explicating the on-the-ground models of agreement-making in the context that these models have been developing since the 1970s. This project, as such, strives to benefit the areas of anthropology, political

  15. Dry period plane of energy: Effects on glucose tolerance in transition dairy cows.

    PubMed

    Mann, S; Leal Yepes, F A; Duplessis, M; Wakshlag, J J; Overton, T R; Cummings, B P; Nydam, D V

    2016-01-01

    Overfeeding energy in the dry period can affect glucose metabolism and the energy balance of transition dairy cows with potential detrimental effects on the ability to successfully adapt to early lactation. The objectives of this study were to investigate the effect of different dry cow feeding strategies on glucose tolerance and on resting concentrations of blood glucose, glucagon, insulin, nonesterified fatty acids (NEFA), and β-hydroxybutyrate (BHB) in the peripartum period. Cows entering second or greater lactation were enrolled at dry-off (57 d before expected parturition) into 1 of 3 treatment groups following a randomized block design: cows that received a total mixed ration (TMR) formulated to meet but not exceed energy requirements during the dry period (n=28, controlled energy); cows that received a TMR supplying approximately 150% of energy requirements during the dry period (n=28, high energy); and cows that were fed the same diet as the controlled energy group for the first 28 d, after which the TMR was formulated to supply approximately 125% of energy requirements until calving (n=28, intermediate energy). Intravenous glucose tolerance tests (IVGTT) with rapid administration of 0.25 g of glucose/kg of body weight were performed 28 and 10d before expected parturition, as well as at 4 and 21 d after calving. Area under the curve for insulin and glucose, maximal concentration and time to half-maximal concentration of insulin and glucose, and clearance rates were calculated. Insulin resistance (IR) indices were calculated from baseline samples obtained during IVGTT and Spearman rank correlations determined between IVGTT parameters and IR indices. Treatment did not affect IVGTT parameters at any of the 4 time points. Correlation between IR indices and IVGTT parameters was generally poor. Overfeeding cows energy in excess of predicted requirements by approximately 50% during the entire dry period resulted in decreased postpartum basal plasma glucose and

  16. Dry period plane of energy: Effects on glucose tolerance in transition dairy cows.

    PubMed

    Mann, S; Leal Yepes, F A; Duplessis, M; Wakshlag, J J; Overton, T R; Cummings, B P; Nydam, D V

    2016-01-01

    Overfeeding energy in the dry period can affect glucose metabolism and the energy balance of transition dairy cows with potential detrimental effects on the ability to successfully adapt to early lactation. The objectives of this study were to investigate the effect of different dry cow feeding strategies on glucose tolerance and on resting concentrations of blood glucose, glucagon, insulin, nonesterified fatty acids (NEFA), and β-hydroxybutyrate (BHB) in the peripartum period. Cows entering second or greater lactation were enrolled at dry-off (57 d before expected parturition) into 1 of 3 treatment groups following a randomized block design: cows that received a total mixed ration (TMR) formulated to meet but not exceed energy requirements during the dry period (n=28, controlled energy); cows that received a TMR supplying approximately 150% of energy requirements during the dry period (n=28, high energy); and cows that were fed the same diet as the controlled energy group for the first 28 d, after which the TMR was formulated to supply approximately 125% of energy requirements until calving (n=28, intermediate energy). Intravenous glucose tolerance tests (IVGTT) with rapid administration of 0.25 g of glucose/kg of body weight were performed 28 and 10d before expected parturition, as well as at 4 and 21 d after calving. Area under the curve for insulin and glucose, maximal concentration and time to half-maximal concentration of insulin and glucose, and clearance rates were calculated. Insulin resistance (IR) indices were calculated from baseline samples obtained during IVGTT and Spearman rank correlations determined between IVGTT parameters and IR indices. Treatment did not affect IVGTT parameters at any of the 4 time points. Correlation between IR indices and IVGTT parameters was generally poor. Overfeeding cows energy in excess of predicted requirements by approximately 50% during the entire dry period resulted in decreased postpartum basal plasma glucose and

  17. Graphene and graphene-like layered transition metal dichalcogenides in energy conversion and storage.

    PubMed

    Wang, Hua; Feng, Hongbin; Li, Jinghong

    2014-06-12

    Being confronted with the energy crisis and environmental problems, the exploration of clean and renewable energy materials as well as their devices are urgently demanded. Two-dimensional (2D) atomically-thick materials, graphene and grpahene-like layered transition metal dichalcogenides (TMDs), have showed vast potential as novel energy materials due to their unique physicochemical properties. In this Review, we outline the typical application of graphene and grpahene-like TMDs in energy conversion and storage fields, and hope to promote the development of 2D TMDs in this field through the analysis and comparisons with the relatively natural graphene. First, a brief introduction of electronic structures and basic properties of graphene and TMDs are presented. Then, we summarize the exciting progress of these materials made in both energy conversion and storage field including solar cells, electrocatalysis, supercapacitors and lithium ions batteries. Finally, the prospects and further developments in these exciting fields of graphene and graphene-like TMDs materials are also suggested.

  18. Mixed transition-metal oxides: design, synthesis, and energy-related applications.

    PubMed

    Yuan, Changzhou; Wu, Hao Bin; Xie, Yi; Lou, Xiong Wen David

    2014-02-01

    A promising family of mixed transition-metal oxides (MTMOs) (designated as Ax B3-x O4 ; A, B=Co, Ni, Zn, Mn, Fe, etc.) with stoichiometric or even non-stoichiometric compositions, typically in a spinel structure, has recently attracted increasing research interest worldwide. Benefiting from their remarkable electrochemical properties, these MTMOs will play significant roles for low-cost and environmentally friendly energy storage/conversion technologies. In this Review, we summarize recent research advances in the rational design and efficient synthesis of MTMOs with controlled shapes, sizes, compositions, and micro-/nanostructures, along with their applications as electrode materials for lithium-ion batteries and electrochemical capacitors, and efficient electrocatalysts for the oxygen reduction reaction in metal-air batteries and fuel cells. Some future trends and prospects to further develop advanced MTMOs for next-generation electrochemical energy storage/conversion systems are also presented.

  19. Calculation of energy levels and transition amplitudes for barium and radium.

    SciTech Connect

    Dzuba, V. A.; Flambaum, V. V.; Physics; Univ. of New South Wales

    2007-01-01

    The radium atom is a promising system for studying parity and time invariance violating weak interactions. However, available experimental spectroscopic data for radium are insufficient for designing an optimal experimental setup. We calculate the energy levels and transition amplitudes for radium states of significant interest. Forty states corresponding to all possible configurations consisting of the 7s, 7p and 6d single-electron states as well as the states of the 7s8s, 7s8p and 7s7d configurations have been calculated. The energies of ten of these states corresponding to the 6d{sup 2}, 7s8s, 7p{sup 2} and 6d7p configurations are not known from experiment. Calculations for barium are used to control the accuracy.

  20. Calculating interaction energies in transition metal complexes with local electron correlation methods

    NASA Astrophysics Data System (ADS)

    Hill, J. Grant; Platts, James A.

    2008-10-01

    The results of density fitting and local approximations applied to the calculation of transition metal-ligand binding energies using second order Møller-Plesset perturbation theory are reported. This procedure accurately reproduces counterpoise corrected binding energies from the canonical method for a range of test complexes. While counterpoise corrections for basis set superposition error are generally small, this procedure can be time consuming, and in some cases gives rise to unphysical dissociation of complexes. In circumventing this correction, a local treatment of electron correlation offers major efficiency savings with little loss of accuracy. The use of density fitting for the underlying Hartree-Fock calculations is also tested for sample Ru complexes, leading to further efficiency gains but essentially no loss in accuracy.

  1. Exclusive Measurements of the b to s gamma Transition Rate and Photon Energy Spectrum

    SciTech Connect

    Lees, J.P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Palano, A.; Eigen, G.; Stugu, B.; Brown, David Nathan; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Koch, H.; Schroeder, T.; Asgeirsson, D.J.; Hearty, C.; Mattison, T.S.; McKenna, J.A.; Khan, A.; Blinov, V.E.; Buzykaev, A.R.; /more authors..

    2012-08-30

    We use 429 fb{sup -1} of e{sup +}e{sup -} collision data collected at the {Upsilon}(4S) resonance with the BABAR detector to measure the radiative transition rate of b {yields} s{gamma} with a sum of 38 exclusive final states. The inclusive branching fraction with a minimum photon energy of 1.9 GeV is found to be {Beta}({bar B} {yields} Xs{gamma}) = (3.29 {+-} 0.19 {+-} 0.48) x 10{sup -4} where the first uncertainty is statistical and the second is systematic. We also measure the first and second moments of the photon energy spectrum and extract the best fit values for the heavy-quark parameters, m{sub b} and {mu}{sub {pi}}{sup 2}, in the kinetic and shape function models.

  2. First-order chiral phase transition in high-energy collisions: Can nucleation prevent spinodal decomposition?

    SciTech Connect

    Scavenius, O.; Dumitru, A.; Fraga, E. S.; Lenaghan, J. T.; Jackson, A. D.

    2001-06-01

    We discuss homogeneous nucleation in a first-order chiral phase transition within an effective field theory approach to low-energy QCD. Exact decay rates and bubble profiles are obtained numerically and compared to analytic results obtained with the thin-wall approximation. The thin-wall approximation overestimates the nucleation rate for any degree of supercooling. The time scale for critical thermal fluctuations is calculated and compared to typical expansion times for high-energy hadronic or heavy-ion collisions. We find that significant supercooling is possible, and the relevant mechanism for phase conversion might be that of spinodal decomposition. Some potential experimental signatures of supercooling, such as an increase in the correlation length of the scalar condensate, are also discussed.

  3. Reactive collisions of very low-energy electrons with H_2+: rotational transitions and dissociative recombination

    NASA Astrophysics Data System (ADS)

    Epée Epée, M. D.; Mezei, J. Zs; Motapon, O.; Pop, N.; Schneider, I. F.

    2016-01-01

    A new series of computations has been performed to obtain cross-sections and rate coefficients for state-to-state rotational transitions in the H2+ ion, induced by collisions with very low-energy electrons. Following our recent work on the HD+ ion (Motapon et al. 2014), and using the same molecular structure data sets, excitations Ni+ rArr Ni++2 for Ni+=0 to 10, and de-excitations Ni+ → Ni+-2, for Ni+=2 to 10, in the energy range 0.01 meV-0.3 eV, have been explored. The calculated cross-sections have been convolved in order to obtain Maxwell rate coefficients for electronic temperatures up to a few hundred of Kelvin. Moreover, Maxwell rate coefficients for dissociative recombination have been calculated for the same initial rotational levels.

  4. Calculation of energy levels, {ital E}1 transition amplitudes, and parity violation in francium

    SciTech Connect

    Dzuba, V.A.; Flambaum, V.V.; Sushkov, O.P.

    1995-05-01

    Many-body perturbation theory in the screened Coulomb interaction was used to calculate energy levels, {ital E}1 trransition amplitudes, and the parity-nonconserving (PNC) {ital E}1 amplitude of the 7{ital s}-8{ital s} transition in francium. The method takes into account the core-polarization effect, the second-order correlations, and the three dominating sequences of higher-order correlation diagrams: screening of the electron-electron interaction, particle-hole interaction, and the iterations of the self-energy operator. The result for the PNC amplitude for {sup 223}Fr is {ital E}1(7{ital s}-8{ital s})=(1.59{plus_minus}{similar_to}1%){times}10{sup {minus}10}{ital iea}{sub {ital B}}({minus}{ital Q}{sub {ital W}}/{ital N}), where {ital Q}{sub {ital W}} is the weak charge of the nucleus, {ital N}=136 is the number of neutrons, {ital e}={vert_bar}{ital e}{vert_bar} is the elementary charge, and {ital a}{sub {ital B}} is the Bohr radius. Our prediction for the position of the 8{ital s} energy level of Fr, which has not been measured yet, is 13 110 cm{sup {minus}1} below the limit of the continuous spectrum. The accuracy of the calculations was controlled by comparison with available experimental data and analogous calculations for cesium. It is estimated to be {similar_to}0.1% for the energy levels and {similar_to}1% for the transition amplitudes.

  5. Free-Free Transitions in the Presence of Laser Fields at Very Low Incident Electron Energy

    NASA Technical Reports Server (NTRS)

    Bhatia, Anand K.; Sinha, Chandana

    2009-01-01

    We study the free-free transition in electron-hydrogenic systems in ground state in presence of an external laser field at very low incident energies. The laser field is treated classically while the collision dynamics is treated quantum mechanically. The laser field is chosen to be monochromatic, linearly polarized and homogeneous. The incident electron is considered to be dressed by the laser in a nonperturbative manner by choosing a Volkov wave function for it The scattering wave function for the electron is solved numerically by taking into account the effect of the electron exchange, short-range as well as of the long-range interactions to get the S and P wave phase shifts while for the higher angular momentum phase shifts, the exchange approximation has only been considered. We calculate the laser-assisted differential cross sections (LADCS) for the aforesaid free-free transition process for single photon absorption/emission. The laser intensity is chosen to be much less than the atomic field intensity. A strong suppression is noted in the LADCS as compared to the field free (FF) cross sections. Unlike the FF ones, the LADCS exhibit some oscillations having a distinct maximum at a low value of the scattering angle depending on the laser parameters as well as on the incident energies.

  6. Free-Free Transitions in the Presence of Laser Fields at Very Low Incident Electron Energy

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Sinha, Chandana

    2010-01-01

    We study the free-free transition in electron-hydrogenic systems in ground state in presence of an external laser field at very loud incident energies. The laser field is treated classically while the collision dynamics is treated quantum mechanically. The laser field is chosen to be monochromatic, linearly polarized and homogeneous. The incident electron is considered to be dressed by the laser in a nonperturbative manner by choosing a Volkov wave function for it. The scattering weave function for the electron is solved numerically by taking into account the effect of the electron exchange, short-range as well as of the long-range interactions to get the S and P wave phase shifts while for the higher angular momentum phase shifts the exchange approximation has only been considered. We calculate the laser assisted differential cross sections (LADCS) for the aforesaid free-free transition process for single photon absorption/emission. The laser intensity is chosen to be much less than the atomic field intensity. A strong suppression is noted in the LADCS as compared to the field free (FF) cross sections. Unlike the FF ones, the LADCS exhibit some oscillations having a distinct maximum at a low value of the scattering angle depending on the laser parameters as well as on the incident energies.

  7. Nonequilibrium self-energy functional approach to the dynamical Mott transition

    NASA Astrophysics Data System (ADS)

    Hofmann, Felix; Eckstein, Martin; Potthoff, Michael

    2016-06-01

    The real-time dynamics of the Fermi-Hubbard model, driven out of equilibrium by quenching or ramping the interaction parameter, is studied within the framework of the nonequilibrium self-energy functional theory. A dynamical impurity approximation with a single auxiliary bath site is considered as a reference system, and the time-dependent hybridization is optimized as prescribed by the variational principle. The dynamical two-site approximation turns out to be useful to study the real-time dynamics on short and intermediate time scales. Depending on the strength of the interaction in the final state, two qualitatively different response regimes are observed. For both weak and strong couplings, qualitative agreement with previous results of nonequilibrium dynamical mean-field theory is found. The two regimes are sharply separated by a critical point at which the low-energy bath degree of freedom decouples in the course of time. We trace the dependence of the critical interaction of the dynamical Mott transition on the duration of the interaction ramp from sudden quenches to adiabatic dynamics and therewith link the dynamical to the equilibrium Mott transition.

  8. Abrupt onset of a second energy gap at the superconducting transition of underdoped Bi2212

    SciTech Connect

    Hussain, Zahid; Lee, W.S.; Vishik, I.M.; Tanaka, K.; Lu, D.H.; Sasagawa, T.; Nagaosa, N.; Devereaux, T.P.; Hussain, Z.; Shen, Z.-X.

    2007-05-26

    he superconducting gap--an energy scale tied to the superconducting phenomena--opens on the Fermi surface at the superconducting transition temperature (Tc) in conventional BCS superconductors. In underdoped high-Tc superconducting copper oxides, a pseudogap (whose relation to the superconducting gap remains a mystery) develops well above Tc (refs 1, 2). Whether the pseudogap is a distinct phenomenon or the incoherent continuation of the superconducting gap above Tc is one of the central questions in high-Tc research3, 4, 5, 6, 7, 8. Although some experimental evidence suggests that the two gaps are distinct9, 10, 11, 12, 13, 14, 15, 16, 17, 18, this issue is still under intense debate. A crucial piece of evidence to firmly establish this two-gap picture is still missing: a direct and unambiguous observation of a single-particle gap tied to the superconducting transition as function of temperature. Here we report the discovery of such an energy gap in underdoped Bi2Sr2CaCu2O8+delta in the momentum space region overlooked in previous measurements. Near the diagonal of Cu?O bond direction (nodal direction), we found a gap that opens at Tc and has a canonical (BCS-like) temperature dependence accompanied by the appearance of the so-called Bogoliubov quasi-particles, a classical signature of superconductivity. This is in sharp contrast to the pseudogap near the Cu?O bond direction (antinodal region) measured in earlier experiments19, 20, 21.

  9. Spectra, energy levels, and energy transition of lanthanide complexes with cinnamic acid and its derivatives

    NASA Astrophysics Data System (ADS)

    Zhou, Kaining; Feng, Zhongshan; Shen, Jun; Wu, Bing; Luo, Xiaobing; Jiang, Sha; Li, Li; Zhou, Xianju

    2016-04-01

    High resolution spectra and luminescent lifetimes of 6 europium(III)-cinnamic acid complex {[Eu2L6(DMF)(H2O)]·nDMF·H2O}m (L = cinnamic acid I, 4-methyl-cinnamic acid II, 4-chloro-cinnamic acid III, 4-methoxy-cinnamic acid IV, 4-hydroxy-cinnamic acid V, 4-nitro-cinnamic acid VI; DMF = N, N-dimethylformamide, C3H7NO) were recorded from 8 K to room temperature. The energy levels of Eu3 + in these 6 complexes are obtained from the spectra analysis. It is found that the energy levels of the central Eu3 + ions are influenced by the nephelauxetic effect, while the triplet state of ligand is lowered by the p-π conjugation effect of the para-substituted functional groups. The best energy matching between the ligand triplet state and the central ion excited state is found in complex I. While the other complexes show poorer matching because the gap of 5D0 and triplet state contracts.

  10. Spectra, energy levels, and energy transition of lanthanide complexes with cinnamic acid and its derivatives.

    PubMed

    Zhou, Kaining; Feng, Zhongshan; Shen, Jun; Wu, Bing; Luo, Xiaobing; Jiang, Sha; Li, Li; Zhou, Xianju

    2016-04-01

    High resolution spectra and luminescent lifetimes of 6 europium(III)-cinnamic acid complex {[Eu2L6(DMF)(H2O)]·nDMF·H2O}m (L=cinnamic acid I, 4-methyl-cinnamic acid II, 4-chloro-cinnamic acid III, 4-methoxy-cinnamic acid IV, 4-hydroxy-cinnamic acid V, 4-nitro-cinnamic acid VI; DMF=N, N-dimethylformamide, C3H7NO) were recorded from 8 K to room temperature. The energy levels of Eu(3+) in these 6 complexes are obtained from the spectra analysis. It is found that the energy levels of the central Eu(3+) ions are influenced by the nephelauxetic effect, while the triplet state of ligand is lowered by the p-π conjugation effect of the para-substituted functional groups. The best energy matching between the ligand triplet state and the central ion excited state is found in complex I. While the other complexes show poorer matching because the gap of (5)D0 and triplet state contracts.

  11. Spectra, energy levels, and energy transition of lanthanide complexes with cinnamic acid and its derivatives.

    PubMed

    Zhou, Kaining; Feng, Zhongshan; Shen, Jun; Wu, Bing; Luo, Xiaobing; Jiang, Sha; Li, Li; Zhou, Xianju

    2016-04-01

    High resolution spectra and luminescent lifetimes of 6 europium(III)-cinnamic acid complex {[Eu2L6(DMF)(H2O)]·nDMF·H2O}m (L=cinnamic acid I, 4-methyl-cinnamic acid II, 4-chloro-cinnamic acid III, 4-methoxy-cinnamic acid IV, 4-hydroxy-cinnamic acid V, 4-nitro-cinnamic acid VI; DMF=N, N-dimethylformamide, C3H7NO) were recorded from 8 K to room temperature. The energy levels of Eu(3+) in these 6 complexes are obtained from the spectra analysis. It is found that the energy levels of the central Eu(3+) ions are influenced by the nephelauxetic effect, while the triplet state of ligand is lowered by the p-π conjugation effect of the para-substituted functional groups. The best energy matching between the ligand triplet state and the central ion excited state is found in complex I. While the other complexes show poorer matching because the gap of (5)D0 and triplet state contracts. PMID:26802538

  12. Alternative electric energy sources for rail transit. Final report. Phase 1. Report for 17 August 1990-16 February 1993

    SciTech Connect

    Uher, R.A.; Howard, J.

    1993-08-01

    After labor costs, electrical energy costs constitute the second largest item in the annual operating budget of rail transit authorities. These costs continue to increase putting heavier burdens on the authorities. Native (local) electric power utility companies are currently the standard sources of electrical energy for rail transit systems. Present deregulation trends in the electric power industry opens the market for competition and lower cost electrical service for transit authorities. In the long term, rail transit operating cost will be reduced. In the context of the report, an alternative energy source means purchasing energy at a time different from when it will be used and/or from a source which is not the local utility. The former case is energy storage and the latter case is termed bypass. The report discusses these sources. Certain conditions are required for a rail transit authority to seriously consider alternative energy sources. The report discusses these conditions and investigates the technical and regulatory issues involved in investigating such sources.

  13. Quantum mechanics on a Möbius ring: Energy levels, symmetry, optical transitions, and level splitting in a magnetic field

    NASA Astrophysics Data System (ADS)

    Li, Zehao; Ram-Mohan, L. R.

    2012-05-01

    We investigate the quantum mechanical energy levels of an electron constrained to motion on a nanoscale Möbius ring by solving the Schrödinger equation on the curved surface. The dimensions of the ring in terms of the lateral and transverse parameters {u,v} for the Möbius ring allow us to identify the quantum numbers for the levels by (nu,nv). We show that the energy levels can still be labeled using the quantum numbers of the cylindrical ring of the same dimensions. While the Hamiltonian has invariance under parity in parameter space, the rotational symmetry about any axis in configuration space is lost, so that the double degeneracy of energy levels for azimuthal quantum number nu≥1, that exists in cylindrical rings, is lifted by a small amount in the Möbius ring. The pattern of level splitting has been identified in terms of the number of twists σ to be 2nu=sσ where s is an integer. The scaling properties of the energy levels with respect to the dimensions of the ring are derived; using these properties, our numerical results which are given for a specific geometry can be extended to rings of other commensurate dimensions. The absence of rotational invariance for the Möbius ring manifests itself through the orbital angular momentum Lz not commuting with the Hamiltonian. Its expectation values are found to have nearly integral as well as half-integral values of ℏ, and its variances are small. The energy levels with half-integral azimuthal quantum numbers (nu) are also close to the approximate formula for the equivalent cylindrical ring, provided such half-integral quantum numbers are allowed for the cylindrical geometry. The Zeeman splitting of the energy levels in an external magnetic field is displayed, together with wave functions at a level anticrossing. The optical transitions between electronic states on the Möbius ring are obtained, and a table of oscillator strengths is provided. The results for energy levels for rings with multiple twists are

  14. Investigation of the energy-averaged double transition density of isoscalar monopole excitations in medium-heavy mass spherical nuclei

    NASA Astrophysics Data System (ADS)

    Gorelik, M. L.; Shlomo, S.; Tulupov, B. A.; Urin, M. H.

    2016-11-01

    The particle-hole dispersive optical model, developed recently, is applied to study properties of high-energy isoscalar monopole excitations in medium-heavy mass spherical nuclei. The energy-averaged strength functions of the isoscalar giant monopole resonance and its overtone in 208Pb are analyzed. In particular, we analyze the energy-averaged isoscalar monopole double transition density, the key quantity in the description of the hadron-nucleus inelastic scattering, and studied the validity of the factorization approximation using semi classical and microscopic one body transition densities, respectively, in calculating the cross sections for the excitation of isoscalar giant resonances by inelastic alpha scattering.

  15. Interband optical transition energy and oscillator strength in a lead based CdSe quantum dot quantum well heterostructure

    SciTech Connect

    Saravanamoorthy, S. N.; Peter, A. John

    2015-06-24

    Binding energies of the exciton and the interband optical transition energies are studied in a CdSe/Pb{sub 1-x}Cd{sub x}Se/CdSe spherical quantum dot-quantum well nanostructure taking into account the geometrical confinement effect. The core and shell are taken as the same material. The initial and final states of energy and the overlap integrals of electron and hole wave functions are determined by the oscillator strength. The oscillator strength and the radiative transition life time with the dot radius are investigated for various Cd alloy content in the core and shell materials.

  16. Evidence and future scenarios of a low-carbon energy transition in Central America: a case study in Nicaragua

    NASA Astrophysics Data System (ADS)

    Barido, Diego Ponce de Leon; Johnston, Josiah; Moncada, Maria V.; Callaway, Duncan; Kammen, Daniel M.

    2015-10-01

    The global carbon emissions budget over the next decades depends critically on the choices made by fast-growing emerging economies. Few studies exist, however, that develop country-specific energy system integration insights that can inform emerging economies in this decision-making process. High spatial- and temporal-resolution power system planning is central to evaluating decarbonization scenarios, but obtaining the required data and models can be cost prohibitive, especially for researchers in low, lower-middle income economies. Here, we use Nicaragua as a case study to highlight the importance of high-resolution open access data and modeling platforms to evaluate fuel-switching strategies and their resulting cost of power under realistic technology, policy, and cost scenarios (2014-2030). Our results suggest that Nicaragua could cost-effectively achieve a low-carbon grid (≥80%, based on non-large hydro renewable energy generation) by 2030 while also pursuing multiple development objectives. Regional cooperation (balancing) enables the highest wind and solar generation (18% and 3% by 2030, respectively), at the least cost (US127 MWh-1). Potentially risky resources (geothermal and hydropower) raise system costs but do not significantly hinder decarbonization. Oil price sensitivity scenarios suggest renewable energy to be a more cost-effective long-term investment than fuel oil, even under the assumption of prevailing cheap oil prices. Nicaragua’s options illustrate the opportunities and challenges of power system decarbonization for emerging economies, and the key role that open access data and modeling platforms can play in helping develop low-carbon transition pathways.

  17. Optimizing the structures of minimum and transition state on the free energy surface.

    PubMed

    Yang, Sheng-Yong; Hristov, Iordan; Fleurat-Lessard, Paul; Ziegler, Tom

    2005-01-13

    Presented here is the application of a scheme for optimizing the structures of minima and transition states on the free energy surface (FES) for a path along a fixed reaction coordinate with the aid of ab initio molecular dynamics (AIMD) simulation. In the direction of the reaction coordinate, the values corresponding to the stationary points were optimized using the quasi-Newton method, in which the gradient of the free energy along the reaction coordinate was obtained by a constraint AIMD method, and the Bofill Hessian update scheme was used. The equilibrium values for the other directions were taken as the corresponding averages in the dynamic simulation. This scheme was applied to several elementary bimolecular addition reactions: (A) BH(3) + H(2)O --> H(2)O.BH(3); (B) BF(3) + NH(3) --> FB(3).NH(3); (C) SO(3) + NH(3) --> O(3)S.NH(3); (D) C(2)H(4) + CCl(2) --> H(4)C(2).CCl(2); (E) Ni(NH(2))(2) + PH(3) --> (NH(2))(2)Ni.PH(3); (F) W(CO)(5) + CO --> W(CO)(6). For reactions A, B, C, and F, no transition state (TS) exists on the potential energy surface (PES). However there is a TS on the FES. This stems from the curvature difference of the PES and -TDeltaS as a function of the reaction coordinate. For all reactions, it is found that the TS shifts toward the complexation product with increasing temperature because of the curvature increase of -TDeltaS. The equilibrium bond distances for the inactive coordinates perpendicular to the reaction coordinate always increase with temperature, which is due to the thermal excitation and anharmonicity of the PES.

  18. Potential energy curves and electronic structure of 3d transition metal hydrides and their cations

    NASA Astrophysics Data System (ADS)

    Goel, Satyender; Masunov, Artëm E.

    2008-12-01

    We investigate gas-phase neutral and cationic hydrides formed by 3d transition metals from Sc to Cu with density functional theory (DFT) methods. The performance of two exchange-correlation functionals, Boese-Martin for kinetics (BMK) and Tao-Perdew-Staroverov-Scuseria (TPSS), in predicting bond lengths and energetics, electronic structures, dipole moments, and ionization potentials is evaluated in comparison with available experimental data. To ensure a unique self-consistent field (SCF) solution, we use stability analysis, Fermi smearing, and continuity analysis of the potential energy curves. Broken-symmetry approach was adapted in order to get the qualitatively correct description of the bond dissociation. We found that on average BMK predicted values of dissociation energies and ionization potentials are closer to experiment than those obtained with high level wave function theory methods. This agreement deteriorates quickly when the fraction of the Hartree-Fock exchange in DFT functional is decreased. Natural bond orbital (NBO) population analysis was used to describe the details of chemical bonding in the systems studied. The multireference character in the wave function description of the hydrides is reproduced in broken-symmetry DFT description, as evidenced by NBO analysis. We also propose a new scheme to correct for spin contamination arising in broken-symmetry DFT approach. Unlike conventional schemes, our spin correction is introduced for each spin-polarized electron pair individually and therefore is expected to yield more accurate energy values. We derive an expression to extract the energy of the pure singlet state from the energy of the broken-symmetry DFT description of the low spin state and the energies of the high spin states (pentuplet and two spin-contaminated triplets in the case of two spin-polarized electron pairs). The high spin states are build with canonical natural orbitals and do not require SCF convergence.

  19. Risk perception & strategic decision making :general insights, a framework, and specific application to electricity generation using nuclear energy.

    SciTech Connect

    Brewer, Jeffrey D.

    2005-11-01

    The objective of this report is to promote increased understanding of decision making processes and hopefully to enable improved decision making regarding high-consequence, highly sophisticated technological systems. This report brings together insights regarding risk perception and decision making across domains ranging from nuclear power technology safety, cognitive psychology, economics, science education, public policy, and neural science (to name a few). It forms them into a unique, coherent, concise framework, and list of strategies to aid in decision making. It is suggested that all decision makers, whether ordinary citizens, academics, or political leaders, ought to cultivate their abilities to separate the wheat from the chaff in these types of decision making instances. The wheat includes proper data sources and helpful human decision making heuristics; these should be sought. The chaff includes ''unhelpful biases'' that hinder proper interpretation of available data and lead people unwittingly toward inappropriate decision making ''strategies''; obviously, these should be avoided. It is further proposed that successfully accomplishing the wheat vs. chaff separation is very difficult, yet tenable. This report hopes to expose and facilitate navigation away from decision-making traps which often ensnare the unwary. Furthermore, it is emphasized that one's personal decision making biases can be examined, and tools can be provided allowing better means to generate, evaluate, and select among decision options. Many examples in this report are tailored to the energy domain (esp. nuclear power for electricity generation). The decision making framework and approach presented here are applicable to any high-consequence, highly sophisticated technological system.

  20. A cumulative energy demand indicator (CED), life cycle based, for industrial waste management decision making.

    PubMed

    Puig, Rita; Fullana-I-Palmer, Pere; Baquero, Grau; Riba, Jordi-Roger; Bala, Alba

    2013-12-01

    Life cycle thinking is a good approach to be used for environmental decision-support, although the complexity of the Life Cycle Assessment (LCA) studies sometimes prevents their wide use. The purpose of this paper is to show how LCA methodology can be simplified to be more useful for certain applications. In order to improve waste management in Catalonia (Spain), a Cumulative Energy Demand indicator (LCA-based) has been used to obtain four mathematical models to help the government in the decision of preventing or allowing a specific waste from going out of the borders. The conceptual equations and all the subsequent developments and assumptions made to obtain the simplified models are presented. One of the four models is discussed in detail, presenting the final simplified equation to be subsequently used by the government in decision making. The resulting model has been found to be scientifically robust, simple to implement and, above all, fulfilling its purpose: the limitation of waste transport out of Catalonia unless the waste recovery operations are significantly better and justify this transport.

  1. Coupling of surface energy with electric potential makes superhydrophobic surfaces corrosion-resistant.

    PubMed

    Ramachandran, Rahul; Nosonovsky, Michael

    2015-10-14

    We study the correlation of wetting properties and corrosion rates on hydrophobized cast iron. Samples of different surface roughnesses (abraded by sandpaper) are studied without coating and with two types of hydrophobic coatings (stearic acid and a liquid repelling spray). The contact angles and contact angle hysteresis are measured using a goniometer while corrosion rates are measured by a potentiodynamic polarization test. The data show a decrease in corrosion current density and an increase in corrosion potential after superhydrophobization. A similar trend is also found in the recent literature data. We conclude that a decrease in the corrosion rate can be attributed to the changing open circuit potential of a coated surface and increased surface area making the non-homogeneous (Cassie-Baxter) state possible. We interpret these results in light of the idea that the inherent surface energy is coupled with the electric potential in accordance with the Lippmann law of electrowetting and Le Châtelier's principle and, therefore, hydrophobization leads to a decrease in the corrosion potential. This approach can be used for novel anti-corrosive coatings. PMID:26344151

  2. Making the most of missing transverse energy: Mass reconstruction from collimated decays

    NASA Astrophysics Data System (ADS)

    Spannowsky, Michael; Wymant, Chris

    2013-04-01

    At hadron colliders invisible particles χ can be inferred only through observation of the transverse component of the vectorial sum of their momenta—missing ET or missing transverse energy (MET)—preventing reconstruction of the masses of their mother particles. Here we outline situations where prior prejudice about the event kinematics allows one to make the most of MET by decomposing it into its expected sum of transverse contributions, each of which may be promoted to a full four-momentum approximating the associated χ. Such prejudice arises when all χ in the event are expected to be light and (anti-)parallel to a visible object, due to spin correlations, back-to-back decays or boosted decays. We focus on the last of these, with boosted semi-invisibly decaying neutralinos widely motivated in supersymmetry (in the presence of light gravitinos, singlinos, photini or pseudo-Goldstini), and demonstrate our simple method’s ability to reconstruct sharp mass peaks from the MET decomposition.

  3. Trade-offs people make: How the perceptions of risks and benefits of nuclear energy are weighed

    SciTech Connect

    Bisconti, A.S.

    1989-01-01

    Negative images of nuclear energy have been a part of everyday life and language in the United States for a long time. Despite that, nuclear energy has a record of remarkable public success. The analysis of trade-offs people make in forming an opinion about nuclear energy is based on 23 national polls of U.S. adults conducted over the past 6 yr for the U.S. Council for Energy Awareness by Cambridge Reports and confirming polls by Gallup. To understand trade-offs people make, it is important to recognize that {approximately}90% of Americans do not feel very well informed about nuclear energy and have changeable attitudes. If asked to make choices, they will weight their most recent impressions. Ultimately, choices about ways to meet future electricity needs will be determined by factors such as availability and cost, as well as acceptability to the public. Most Americans demonstrate a pragmatism in their trade-offs that is in step with that reality. But the trade-offs that people make will depend on their awareness of the benefits that nuclear energy provides.

  4. Energy budget increases reduce mean streamflow more than snow–rain transitions: using integrated modeling to isolate climate change impacts on Rocky Mountain hydrology

    NASA Astrophysics Data System (ADS)

    Foster, Lauren M.; Bearup, Lindsay A.; Molotch, Noah P.; Brooks, Paul D.; Maxwell, Reed M.

    2016-04-01

    In snow-dominated mountain regions, a warming climate is expected to alter two drivers of hydrology: (1) decrease the fraction of precipitation falling as snow; and (2) increase surface energy available to drive evapotranspiration. This study uses a novel integrated modeling approach to explicitly separate energy budget increases via warming from precipitation phase transitions from snow to rain in two mountain headwaters transects of the central Rocky Mountains. Both phase transitions and energy increases had significant, though unique, impacts on semi-arid mountain hydrology in our simulations. A complete shift in precipitation from snow to rain reduced streamflow between 11% and 18%, while 4 °C of uniform warming reduced streamflow between 19% and 23%, suggesting that changes in energy-driven evaporative loss, between 27% and 29% for these uniform warming scenarios, may be the dominant driver of annual mean streamflow in a warming climate. Phase changes induced a flashier system, making water availability more susceptible to precipitation variability and eliminating the runoff signature characteristic of snowmelt-dominated systems. The impact of a phase change on mean streamflow was reduced as aridity increased from west to east of the continental divide.

  5. Some behavioral aspects of energy descent: how a biophysical psychology might help people transition through the lean times ahead

    PubMed Central

    De Young, Raymond

    2014-01-01

    We may soon face biophysical limits to perpetual growth. Energy supplies may tighten and then begin a long slow descent while defensive expenditures rise to address problems caused by past resource consumption. The outcome may be significant changes in daily routines at the individual and community level. It is difficult to know when this scenario might begin to unfold but it clearly would constitute a new behavioral context, one that the behavioral sciences least attends to. Even if one posits a less dramatic scenario, people may still need to make many urgent and perhaps unsettling transitions. And while a robust response would be needed, it is not at all clear what should be the details of that response. Since it is likely that no single response will fix things everywhere, for all people or for all time, it would be useful to conduct many social experiments. Indeed, a culture of small experiments should be fostered which, at the individual and small group level, can be described as behavioral entrepreneurship. This may have begun, hidden in plain sight, but more social experiments are needed. To be of help, it may be useful to both package behavioral insights in a way that is practitioner-oriented and grounded in biophysical trends and to propose a few key questions that need attention. This paper begins the process of developing a biophysical psychology, incomplete as it is at this early stage. PMID:25404926

  6. Some behavioral aspects of energy descent: how a biophysical psychology might help people transition through the lean times ahead.

    PubMed

    De Young, Raymond

    2014-01-01

    We may soon face biophysical limits to perpetual growth. Energy supplies may tighten and then begin a long slow descent while defensive expenditures rise to address problems caused by past resource consumption. The outcome may be significant changes in daily routines at the individual and community level. It is difficult to know when this scenario might begin to unfold but it clearly would constitute a new behavioral context, one that the behavioral sciences least attends to. Even if one posits a less dramatic scenario, people may still need to make many urgent and perhaps unsettling transitions. And while a robust response would be needed, it is not at all clear what should be the details of that response. Since it is likely that no single response will fix things everywhere, for all people or for all time, it would be useful to conduct many social experiments. Indeed, a culture of small experiments should be fostered which, at the individual and small group level, can be described as behavioral entrepreneurship. This may have begun, hidden in plain sight, but more social experiments are needed. To be of help, it may be useful to both package behavioral insights in a way that is practitioner-oriented and grounded in biophysical trends and to propose a few key questions that need attention. This paper begins the process of developing a biophysical psychology, incomplete as it is at this early stage. PMID:25404926

  7. Relativistic many-body calculations of excitation energies and transition rates from core-excited states in copperlike ions

    NASA Astrophysics Data System (ADS)

    Safronova, U. I.; Johnson, W. R.; Shlyaptseva, A.; Hamasha, S.

    2003-05-01

    Energies of (3s23p63d94l4l'), (3s23p53d104l4l'), and (3s3p63d104l4l') states for Cu-like ions with Z=30 100 are evaluated to second order in relativistic many-body perturbation theory (RMBPT) starting from a Ni-like Dirac-Fock potential. Second-order Coulomb and Breit-Coulomb interactions are included. Correction for the frequency dependence of the Breit interaction is taken into account in lowest order. The Lamb shift correction to energies is also included in lowest order. Intrinsic particle-particle-hole contributions to energies are found to be 20 30 % of the sum of one- and two-body contributions. Transition rates and line strengths are calculated for the 3l-4l' electric-dipole (E1) transitions in Cu-like ions with nuclear charge Z=30 100. RMBPT including the Breit interaction is used to evaluate retarded E1 matrix elements in length and velocity forms. First-order RMBPT is used to obtain intermediate coupling coefficients, and second-order RMBPT is used to calculate transition matrix elements. A detailed discussion of the various contributions to the dipole- matrix elements and energy levels is given for copperlike tungsten (Z=74). The transition energies used in the calculation of oscillator strengths and transition rates are from second-order RMBPT. Trends of the transition rates as functions of Z are illustrated graphically for selected transitions. Comparisons are made with available experimental data. These atomic data are important in the modeling of M-shell radiation spectra of heavy ions generated in electron-beam ion trap experiments and in M-shell diagnostics of plasmas.

  8. Transition-metal-nitride-based thin films as novel energy harvesting materials

    PubMed Central

    Kerdsongpanya, Sit; Alling, Björn

    2016-01-01

    The last few years have seen a rise in the interest in early transition-metal and rare-earth nitrides, primarily based on ScN and CrN, for energy harvesting by thermoelectricity and piezoelectricity. This is because of a number of important advances, among those the discoveries of exceptionally high piezoelectric coupling coefficient in (Sc,Al)N alloys and of high thermoelectric power factors of ScN-based and CrN-based thin films. These materials also constitute well-defined model systems for investigating thermodynamics of mixing for alloying and nanostructural design for optimization of phase stability and band structure. These features have implications for and can be used for tailoring of thermoelectric and piezoelectric properties. In this highlight article, we review the ScN- and CrN-based transition-metal nitrides for thermoelectrics, and drawing parallels with piezoelectricity. We further discuss these materials as a models systems for general strategies for tailoring of thermoelectric properties by integrated theoretical–experimental approaches. PMID:27358737

  9. Electron-impact dissociative double ionization of N2 and CO: Dependence of transition probability on impact energy

    NASA Astrophysics Data System (ADS)

    Pandey, A.; Kumar, P.; Banerjee, S. B.; Subramanian, K. P.; Bapat, B.

    2016-04-01

    We present an experimental and computational analysis of dissociative double ionization of N2 and CO molecules under electron impact. Experiments are performed at three energies, viz. 1, 3, and 5 keV, in order to observe the effect of impact energy on the dissociative ionization kinematics. We compare the kinetic energy release (KER) distributions of the charge symmetric dissociation channels of N22 + and CO2 + at these impact energies. An approximately linear trend between the transition energy and the expected KER values is inferred on the basis of the calculated potential energy curves of the dications. Experimentally, the normalized differential KER cross sections for these channels show an increasing trend in the low KER range and a decreasing trend in the high KER range as the electron-impact energy is increased. This observation indicates that the transition probability for excitation to different molecular ion states is not only a function of energy difference between the ground and excited states, but also a complicated function of the impact energy. In addition, nature of the observed trend in the differential KER cross sections differs significantly from their differential transition probability, which are calculated using inelastic collision model for fast-electron-impact case.

  10. Free-energy landscape of alcohol driven coacervation transition in aqueous gelatin solutions

    NASA Astrophysics Data System (ADS)

    Gupta, Amarnath; Reena, Bohidar, H. B.

    2006-08-01

    Liquid-liquid phase separation of a homogeneous polyampholyte (gelatin) solution into a dense polymer-rich coacervate and the dilute supernatant phase is discussed through free-energy landscape formalism. We have evaluated the free energy and entropy of the system as it undergoes the phenomenon of simple coacervation, driven by the addition of a nonsolvent. Electrophoretic mobility (μ) and turbidity measurements were performed on 0.01% and 0.05%(w/v) aqueous gelatin solutions that were driven towards coacervation by the addition of ethanol. The mobility of the polyampholyte molecules, which was typically μ ≈0.38±0.02μm/scm/V in water, gradually reduced for the soluble intermolecular complexes to a plateau value of μ ≈0.11±0.01μm/scm/V as the ethanol volume fraction equaled φns≈0.47±0.03, which coincided with the first appearance of coacervate droplets (coacervation transition) observed from turbidity measurements, a behavior found to be invariant of gelatin concentration. These results were used as input to the theoretical model to explicitly construct the free-energy landscape for a single gelatin chain and the global system comprising the polymer-rich coacervate and the dilute supernatant phase.

  11. Binding energies of exciton complexes in transition metal dichalcogenide monolayers and effect of dielectric environment

    NASA Astrophysics Data System (ADS)

    Kylänpää, Ilkka; Komsa, Hannu-Pekka

    2015-11-01

    Excitons, trions, biexcitons, and exciton-trion complexes in two-dimensional transition metal dichalcogenide sheets of MoS2, MoSe2, MoTe2, WS2, and WSe2 are studied by means of density functional theory and path-integral Monte Carlo method in order to accurately account for the particle-particle correlations. In addition, the effect of dielectric environment on the properties of these exciton complexes is studied by modifying the effective interaction potential between particles. Calculated exciton and trion binding energies are consistent with previous experimental and computational studies, and larger systems such as biexciton and exciton-trion complex are found highly stable. Binding energies of biexcitons are similar to or higher than those of trions, but the binding energy of the trion depends significantly stronger on the dielectric environment than that of biexciton. Therefore, as a function of an increasing dielectric constant of the environment the exciton-trion complex "dissociates" to a biexciton rather than to an exciton and a trion.

  12. Synthesis and characterization of nanostructured transition metal oxides for energy storage devices

    NASA Astrophysics Data System (ADS)

    Kim, Jong Woung

    Finding a promising material and constructing a new method to have both high energy and power are key issues for future energy storage systems. This dissertation addresses three different materials systems to resolve those issues. Pseudocapacitive materials such as RuO2 and MnO2 display high capacitance but Nb2O5, displays a different charge storage mechanism, one highly dependent on its crystal phase rather than its surface area. Various sol-gel techniques were used to synthesize the different phases of Nb2O5 and electrochemical testing was used to study their charge storage with some phases displaying comparable charge storage to MnO2. To overcome the electrical limitations of using an insulating material, the core-shell structure (Nb2O 5/C) was also examined and the method could be generalized to improve other pseudocapacitors. Besides electronic conductivity, the diffusion of the electrolyte ions through the shell material is a critical factor for fast charging/discharging in the core-shell structure. This dissertation also involves another topic, a reconfigurable electrode, that displays both high energy and power density. By constructing a reconfigurable electrode which has different electrical properties (metallic or insulating state) depending on the amount of intercalated `guest' ions into `host' material, it can be used as a battery or electrochemical capacitor material in the insulating or metallic state respectively. Metal oxide bronzes having metal-insulator transition were investigated in this study.

  13. Relation between ligand design and transition energy for the praseodymium ion in crystals.

    PubMed

    Zhou, Xianju; Tanner, Peter A

    2015-01-01

    Ten substituted benzoate complexes of Pr(3+) of the type [Pr(XC6H4COO)3(H2O)n(DMF)m]p·(DMF)q (X = OCH3, NO2, OH, F, Cl, NH2) have been synthesized, and for eight of these crystallographic data are available. The electronic absorption and emission spectra of the complexes have been recorded and interpreted at temperatures down to 10 K for transitions involving the (3)P0 and (1)D2 J-multiplet terms. Generally, the electron-withdrawing groups X in the benzoate moiety lead to higher (3)P0 energy than electron-donating groups. Empirical relations have been found between the energies of the (3)P0 and (1)D2(1) levels and the Hammett sigma constants for substituents and the unit cell volume per Pr(3+) ion. The latter relationship is indicative of a correlation between the electronic state energy and the ligand dipole polarizability. This has been confirmed by reference to literature data for the LaX3:Pr(3+) systems, so that the ligand dipole polarizability is a key factor in determining the nephelauxetic shifts of 4f(N) ions in crystals.

  14. Relation between ligand design and transition energy for the praseodymium ion in crystals.

    PubMed

    Zhou, Xianju; Tanner, Peter A

    2015-01-01

    Ten substituted benzoate complexes of Pr(3+) of the type [Pr(XC6H4COO)3(H2O)n(DMF)m]p·(DMF)q (X = OCH3, NO2, OH, F, Cl, NH2) have been synthesized, and for eight of these crystallographic data are available. The electronic absorption and emission spectra of the complexes have been recorded and interpreted at temperatures down to 10 K for transitions involving the (3)P0 and (1)D2 J-multiplet terms. Generally, the electron-withdrawing groups X in the benzoate moiety lead to higher (3)P0 energy than electron-donating groups. Empirical relations have been found between the energies of the (3)P0 and (1)D2(1) levels and the Hammett sigma constants for substituents and the unit cell volume per Pr(3+) ion. The latter relationship is indicative of a correlation between the electronic state energy and the ligand dipole polarizability. This has been confirmed by reference to literature data for the LaX3:Pr(3+) systems, so that the ligand dipole polarizability is a key factor in determining the nephelauxetic shifts of 4f(N) ions in crystals. PMID:25474732

  15. Periodic orbits, damped transitions and targeted energy transfers in oscillators with vibro-impact attachments

    NASA Astrophysics Data System (ADS)

    Lee, Young S.; Nucera, Francesco; Vakakis, Alexander F.; McFarland, D. Michael; Bergman, Lawrence A.

    2009-09-01

    We study complex damped and undamped dynamics and targeted energy transfers (TETs) in systems of coupled oscillators, consisting of single-degree-of-freedom primary linear oscillators (LOs) with vibro-impact attachments, acting, in essence, as vibro-impact nonlinear energy sinks (VI NESs). First, the complicated dynamics of such VI systems is demonstrated by computing the VI periodic orbits of underlying Hamiltonian systems and depicting them in appropriate frequency-energy plots (FEPs). Then, VI damped transitions and distinct ways of passive TETs from the linear oscillators to the VI attachments for various parameter ranges and initial conditions are investigated. As in the case of smooth stiffness nonlinearity [Y. Lee, G. Kerschen, A. Vakakis, P. Panagopoulos, L. Bergman, D.M. McFarland, Complicated dynamics of a linear oscillator with a light, essentially nonlinear attachment, Physica D 204 (1-2) (2005) 41-69], both fundamental and subharmonic TET can be realized in the VI systems under consideration. It is found that the most efficient mechanism for VI TET is through the excitation of highly energetic VI impulsive orbits (IOs), i.e., of periodic or quasiperiodic orbits corresponding to zero initial conditions except for the initial velocities of the linear oscillators. In contrast to NESs with smooth essential nonlinearities considered in previous works, VI NESs are capable of passively absorbing and locally dissipating significant portions of the energies of the primary systems to which they are attached, at fast time scale. This renders such devices suitable for applications, like seismic mitigation, where dissipation of vibration energy in the early, highly energetic regime of the motion is a critical requirement.

  16. Energy dissipation in heavy systems: the transition from quasi-elastic to deep-inelastic scattering

    SciTech Connect

    Rehm, K.E.; van den Berg, A.; Kolata, J.J.; Kovar, D.G.; Kutschera, W.; Rosner, G.; Stephans, G.S.F.; Yntema, J.L.; Lee, L.L.

    1984-01-01

    The interaction of medium mass projectiles (A = 28 - 64) with /sup 208/Pb has been studied using a split-pole spectrograph which allows single mass and charge identification. The reaction process in all systems studied so far is dominated by quasi-elastic neutron transfer reactions, especially at incident energies in the vicinity of the Coulomb barrier. In addition to the quasi-elastic component deep inelastic contributions are present in all reaction channels. The good mass and charge separation allows to generate Wilczynski plots for individual channels; for the system /sup 48/Ti + /sup 208/Pb we observe that the transition between the quasi-elastic and deep-inelastic reactions occurs around Q = -(30 to 35) MeV.

  17. Test of the Chevallier-Polarski-Linder parametrization for rapid dark energy equation of state transitions

    SciTech Connect

    Linden, Sebastian; Virey, Jean-Marc

    2008-07-15

    We test the robustness and flexibility of the Chevallier-Polarski-Linder (CPL) parametrization of the dark energy equation of state w(z)=w{sub 0}+w{sub a}(z/1+z) in recovering a four-parameter steplike fiducial model. We constrain the parameter space region of the underlying fiducial model where the CPL parametrization offers a reliable reconstruction. It turns out that non-negligible biases leak into the results for recent (z<2.5) rapid transitions, but that CPL yields a good reconstruction in all other cases. The presented analysis is performed with supernova Ia data as forecasted for a space mission like SNAP/JDEM, combined with future expectations for the cosmic microwave background shift parameter R and the baryonic acoustic oscillation parameter A.

  18. Universal features of the free-energy functional at the freezing transition for repulsive potentials.

    PubMed

    Verma, Anurag; Ford, David M

    2011-05-01

    The free-energy difference between coexisting solid and liquid phases is studied in the context of classical density functional theory (DFT). A bridge function is used to represent the higher-order (n>2) terms in the perturbative expansion of the excess Helmholtz free energy, and the values of this bridge function within the solid lattice are determined by inversion using literature Monte Carlo simulation results. Four potential models, specifically hard-sphere and inverse twelfth-, sixth-, and fourth-power repulsive, are studied. The face-centered cubic (fcc) solid is considered for the hard-sphere and inverse twelfth- and sixth-power potentials, while the body-centered cubic (bcc) solid is considered for the inverse sixth- and fourth-power potentials. For a given solid structure there is a remarkable similarity among the bridge functions for different potentials that is analogous to the universality in the sum of elementary diagrams, or bridge functions, of liquid-state theory as originally observed by Rosenfeld and Ashcroft [Phys. Rev. A 20, 1208 (1979)]. In further analogy with liquid-state theory, the bridge functions in the present problem are plotted as functionals of the second-order convolution term in the perturbative expansion. In each case, the plot indicates a unique functionality in the dense regions of the solid near the lattice sites but a scattered and nonunique behavior in the void regions. Interestingly, knowledge of the functional relationship in the unique region near the lattice sites seems to be sufficient to quantitatively model the solid-fluid phase transition. These qualitative observations are true for both fcc and bcc solid phases, although there are some quantitative differences between them. The findings suggest that pursuit of a closure-based DFT of solid-fluid transitions may be profitable. PMID:21728493

  19. Relationship between digesta transit time and apparent metabolisable energy value of wheat in chickens.

    PubMed

    Hughes, R J

    2008-11-01

    1. This study tested the hypotheses that: (a) apparent metabolisable energy (AME) values and whole tract transit time (WTTT) were related, and that (b) the relationship between AME and WTTT differed between male and female Ross broiler chickens. 2. Enzyme products with xylanase activity were added to a basal diet to provide 4 dietary treatments comprising control (no enzyme), Avizyme 1300 (1 kg/tonne), Kemzyme W1 (1 kg/tonne), and Bio-Feed Wheat CT (200 g/tonne). The basal diet comprised (in g/kg), 800 wheat, 155 casein, 20 dicalcium phosphate, 11 limestone, 7 D,L-methionine, 2 vitamin and mineral premix, 3 sodium chloride and 2 choline chloride (60%). 3. AME values for diets were determined in a 7-d energy balance study commencing when chickens were 21 d of age. WTTT was the time elapsed (in min), from time of administration by oral gavage of 200 mg ferric oxide in a gelatine capsule, to time of first observation of the distinctive red colouration in droppings. 4. The mean AME value for the wheat was high (15.7 MJ/kg dry matter) and ranged from 14.4 to 16.3 MJ/kg dry matter for individual birds. Mean WTTT was 206 min and ranged from 105 to 429 min. AME and WTTT were unaffected by enzyme addition to the diet, and the interaction between diet and gender was not significant. 5. There was a significant but weak positive relationship between AME and whole tract transit time, with AME increasing by 2.2 kJ/min. This relationship was unaffected by gender of the chicken. PMID:19093244

  20. Turbulence kinetic energy budget during the afternoon transition - Part 2: A simple TKE model

    NASA Astrophysics Data System (ADS)

    Nilsson, Erik; Lothon, Marie; Lohou, Fabienne; Pardyjak, Eric; Hartogensis, Oscar; Darbieu, Clara

    2016-07-01

    A simple model for turbulence kinetic energy (TKE) and the TKE budget is presented for sheared convective atmospheric conditions based on observations from the Boundary Layer Late Afternoon and Sunset Turbulence (BLLAST) field campaign. It is based on an idealized mixed-layer approximation and a simplified near-surface TKE budget. In this model, the TKE is dependent on four budget terms (turbulent dissipation rate, buoyancy production, shear production and vertical transport of TKE) and only requires measurements of three available inputs (near-surface buoyancy flux, boundary layer depth and wind speed at one height in the surface layer) to predict vertical profiles of TKE and TKE budget terms.This simple model is shown to reproduce some of the observed variations between the different studied days in terms of near-surface TKE and its decay during the afternoon transition reasonably well. It is subsequently used to systematically study the effects of buoyancy and shear on TKE evolution using idealized constant and time-varying winds during the afternoon transition. From this, we conclude that many different TKE decay rates are possible under time-varying winds and that generalizing the decay with simple scaling laws for near-surface TKE of the form tα may be questionable.The model's errors result from the exclusion of processes such as elevated shear production and horizontal advection. The model also produces an overly rapid decay of shear production with height. However, the most influential budget terms governing near-surface TKE in the observed sheared convective boundary layers are included, while only second-order factors are neglected. Comparison between modeled and averaged observed estimates of dissipation rate illustrates that the overall behavior of the model is often quite reasonable. Therefore, we use the model to discuss the low-turbulence conditions that form first in the upper parts of the boundary layer during the afternoon transition and are only

  1. New energy geographics: Powershed politics and hydropower decision making in Yunnan, China

    NASA Astrophysics Data System (ADS)

    Magee, Darrin L.

    This study analyzes decision making related to large-scale hydropower in China's Yunnan Province. The study has five aims: to contribute empirical knowledge about hydropower development on the Lancang (upper Mekong) and Nu (upper Salween) Rivers; to explain the institutional, legal, and political economic factors affecting decisions about large-scale hydropower; to use the peculiarities of water to complicate models of center-local and interprovincial relations; to underscore the importance of geographic constructs in framing and legitimizing certain development patterns; and to contribute to debates on China's "civil society." After reviewing literature in political ecology, China geography and area studies, and scale theory, I develop an analytical framework called a powershed. Like a watershed, a powershed reflects a space over which a resource is collected. It also has political meaning: first, as a way of understanding how policies and investments are deployed to facilitate electric power transfers from Yunnan to Guangdong; and second, as a means for signaling the importance of geographic constructs in legitimizing certain discourses, actions, actors, and policies while de-legitimizing others. Most importantly, it provides a dynamic, context-specific analytical framework that enables us to trace the processes of hydropower development. Next, I provide details of Lancang and Nu hydropower and of the energy geographies to which the projects belong. My analysis picks apart decision flows from blueprint to dam, identifying two distinctly different perspectives. I conclude by arguing first that supra-provincial institutions such as watershed commissions, hydropower companies, and grid companies are important in shaping relations between Guangdong and Yunnan vis-a-vis electricity production, distribution, and consumption. A corollary is that reforms in the electricity and water sectors have created overlapping responsibilities and unclear jurisdiction among

  2. The WiggleZ Dark Energy Survey: the transition to large-scale cosmic homogeneity

    NASA Astrophysics Data System (ADS)

    Scrimgeour, Morag I.; Davis, Tamara; Blake, Chris; James, J. Berian; Poole, Gregory B.; Staveley-Smith, Lister; Brough, Sarah; Colless, Matthew; Contreras, Carlos; Couch, Warrick; Croom, Scott; Croton, Darren; Drinkwater, Michael J.; Forster, Karl; Gilbank, David; Gladders, Mike; Glazebrook, Karl; Jelliffe, Ben; Jurek, Russell J.; Li, I.-hui; Madore, Barry; Martin, D. Christopher; Pimbblet, Kevin; Pracy, Michael; Sharp, Rob; Wisnioski, Emily; Woods, David; Wyder, Ted K.; Yee, H. K. C.

    2012-09-01

    We have made the largest volume measurement to date of the transition to large-scale homogeneity in the distribution of galaxies. We use the WiggleZ survey, a spectroscopic survey of over 200 000 blue galaxies in a cosmic volume of ˜1 h-3 Gpc3. A new method of defining the 'homogeneity scale' is presented, which is more robust than methods previously used in the literature, and which can be easily compared between different surveys. Due to the large cosmic depth of WiggleZ (up to z = 1), we are able to make the first measurement of the transition to homogeneity over a range of cosmic epochs. The mean number of galaxies N(< r) in spheres of comoving radius r is proportional to r3 within 1 per cent, or equivalently the fractal dimension of the sample is within 1 per cent of D2 = 3, at radii larger than 71 ± 8 h-1Mpc at z ˜ 0.2, 70 ± 5 h-1 Mpc at z ˜ 0.4, 81 ± 5 h-1 Mpc at z ˜ 0.6 and 75 ± 4 h-1 Mpc at z ˜ 0.8. We demonstrate the robustness of our results against selection function effects, using a Λ cold dark matter (ΛCDM) N-body simulation and a suite of inhomogeneous fractal distributions. The results are in excellent agreement with both the ΛCDM N-body simulation and an analytical ΛCDM prediction. We can exclude a fractal distribution with fractal dimension below D2 = 2.97 on scales from ˜80 h-1 Mpc up to the largest scales probed by our measurement, ˜300 h-1 Mpc, at 99.99 per cent confidence.

  3. Relativistic Many-body Moller-Plesset Perturbation Theory Calculations of the Energy Levels and Transition Probabilities in Na- to P-like Xe Ions

    SciTech Connect

    Vilkas, M J; Ishikawa, Y; Trabert, E

    2007-03-27

    Relativistic multireference many-body perturbation theory calculations have been performed on Xe{sup 43+}-Xe{sup 39+} ions, resulting in energy levels, electric dipole transition probabilities, and level lifetimes. The second-order many-body perturbation theory calculation of energy levels included mass shifts, frequency-dependent Breit correction and Lamb shifts. The calculated transition energies and E1 transition rates are used to present synthetic spectra in the extreme ultraviolet range for some of the Xe ions.

  4. Relative edge energy in the stability of transition metal nanoclusters of different motifs

    NASA Astrophysics Data System (ADS)

    Zhao, X. J.; Xue, X. L.; Guo, Z. X.; Li, S. F.

    2016-06-01

    When a structure is reduced to a nanometer scale, the proportion of the lowly-coordinated edge atoms increases significantly, which can play a crucial role in determining both their geometric and electronic properties, as demonstrated by the recently established generalized Wulff construction principle [S. F. Li, et al., Phys. Rev. Lett., 2013, 111, 115501]. Consequently, it is of great interest to clarify quantitatively the role of the edge atoms that dominate the motifs of these nanostructures. In principle, establishing an effective method valid for determining the absolute value of the surface energy and particularly the edge energy for a given nanostructure is expected to resolve such a problem. However, hitherto, it is difficult to obtain the absolute edge energy of transition metal clusters, particularly when their sizes approach the nanometer regime. In this paper, taking Ru nanoclusters as a prototypical example, our first-principles calculations introduce the concept of relative edge energy (REE), reflecting the net edge atom effect over the surface (facet) atom effect, which is fairly powerful to quasi-quantitatively estimate the critical size at which the crossover occurs between different configurations of a given motif, such as from an icosahedron to an fcc nanocrystal. By contrast, the bulk effect should be re-considered to rationalize the power of the REE in predicting the relative stability of larger nanostructures between different motifs, such as fcc-like and hcp-like nanocrystals.When a structure is reduced to a nanometer scale, the proportion of the lowly-coordinated edge atoms increases significantly, which can play a crucial role in determining both their geometric and electronic properties, as demonstrated by the recently established generalized Wulff construction principle [S. F. Li, et al., Phys. Rev. Lett., 2013, 111, 115501]. Consequently, it is of great interest to clarify quantitatively the role of the edge atoms that dominate the

  5. Involving the public in decision-making at federal facilities: The Department of Energy experience

    SciTech Connect

    Gesalman, C.M.

    1996-12-31

    The Department of Energy is involved in cleanup of a wide variety of sites used in the development and production of nuclear weapons. Substantial and increasing efforts have been made to involve the public in the planning and implementation of the cleanup projects. Early in the program, public participation was mainly an information transfer effort. More recently, innovative techniques have been used to increase public understanding of the tradeoffs required in making cleanup decisions (e.g., more stringent cleanup standards lead to higher costs). Sites now realize that relationships are key and are working to develop them. Advisory boards have been established at several sites. The methods of forming the boards have varied from site to site, as have the size of the group and the issues addressed. The effectiveness of the boards in their goal of improving public participation at the sites will be evaluated in the next fiscal year. DOE has sought public input on an increasing number of issues, such as future use of its facilities, environmental justice concerns, and budget development. Assumptions about future use of sites are crucial to setting realistic cleanup standards and controlling costs. Decisions made in the early phases of the budget process are now based in part on stakeholder input regarding priorities; for example, stakeholder concerns about and support for emphasizing plutonium cleanup at Rocky Flats have led to changes in priorities between the materials stabilization and environmental restoration programs. Environmental justice has become an increasing issue; sites must ensure that public participation programs effectively reach minority and low-income populations.

  6. Students' Socioscientific Reasoning and Decision-making on Energy-related Issues—Development of a measurement instrument

    NASA Astrophysics Data System (ADS)

    Sakschewski, Mark; Eggert, Sabina; Schneider, Susanne; Bögeholz, Susanne

    2014-09-01

    The concept of energy is one key component of science education curricula worldwide. While it is still being taught in many science classrooms from a mainly conceptual knowledge perspective, the need to frame the concept of energy as a socioscientific issue and implement it in the context of citizenship education and education for sustainable development, is getting more and more explicit. As we will be faced with limited fossil fuels and the consequences of global climate change in the future, students have to be supported in becoming literate citizens who are able to reach informed energy-related decisions. In this article, we focus on students' reasoning and decision-making processes about socioscientific energy-related issues. In more detail, we developed a paper-and-pencil measurement instrument to assess secondary school students' competencies in this domain. The functioning of the measurement instrument was analysed with a sample of 850 students from grades 6, 8, 10 and 12 using item response theory. Findings show that the measurement instrument functions in terms of reliability and validity. Concerning student ability, elaborate reasoning and decision-making was characterised by the use of trade-offs and the ability to weigh arguments and to reflect on the structure of reasoning and decision-making processes. The developed measurement instrument provides a complement for existing test instruments on conceptual knowledge about the concept of energy. It aims to contribute to a change in teaching about energy, especially in physics education in the sense of education for sustainable development.

  7. Scaled free energies, power-law potentials, strain pseudospins, and quasiuniversality for first-order structural transitions

    NASA Astrophysics Data System (ADS)

    Shenoy, S. R.; Lookman, T.; Saxena, A.

    2010-10-01

    We consider ferroelastic first-order phase transitions with NOP order-parameter strains entering Landau free energies as invariant polynomials that have NV structural-variant Landau minima. The total free energy includes (seemingly innocuous) harmonic terms, in the n=6-NOP nonorder-parameter strains. Four three-dimensional (3D) transitions are considered, tetragonal/orthorhombic, cubic/tetragonal, cubic/trigonal, and cubic/orthorhombic unit-cell distortions, with, respectively, NOP=1 , 2, 3, and 2; and NV=2 , 3, 4, and 6. Five two-dimensional (2D) transitions are also considered, as simpler examples. Following Barsch and Krumhansl, we scale the free energy to absorb most material-dependent elastic coefficients into an overall prefactor, by scaling in an overall elastic energy density; a dimensionless temperature variable; and the spontaneous-strain magnitude at transition λ≪1 . To leading order in λ the scaled Landau minima become material independent, in a kind of “quasiuniversality.” The scaled minima in NOP -dimensional order-parameter space, fall at the center and at the NV corners, of a transition-specific polyhedron inscribed in a sphere, whose radius is unity at transition. The “polyhedra” for the four 3D transitions are, respectively, a line, a triangle, a tetrahedron, and a hexagon. We minimize the n terms harmonic in the nonorder-parameter strains, by substituting solutions of the “no dislocation” St Venant compatibility constraints, and explicitly obtain power-law anisotropic, order-parameter interactions, for all transitions. In a reduced discrete-variable description, the competing minima of the Landau free energies induce unit-magnitude pseudospin vectors, with NV+1 values, pointing to the polyhedra corners and the (zero-value) center. The total scaled free energies then become ZNV+1 clocklike pseudospin Hamiltonians, with temperature-dependent local Landau terms, nearest-neighbor Ginzburg couplings, and power-law St Venant

  8. Free energy of conformational transition paths in biomolecules: The string method and its application to myosin VI

    PubMed Central

    Ovchinnikov, Victor; Karplus, Martin; Vanden-Eijnden, Eric

    2011-01-01

    A set of techniques developed under the umbrella of the string method is used in combination with all-atom molecular dynamics simulations to analyze the conformation change between the prepowerstroke (PPS) and rigor (R) structures of the converter domain of myosin VI. The challenges specific to the application of these techniques to such a large and complex biomolecule are addressed in detail. These challenges include (i) identifying a proper set of collective variables to apply the string method, (ii) finding a suitable initial string, (iii) obtaining converged profiles of the free energy along the transition path, (iv) validating and interpreting the free energy profiles, and (v) computing the mean first passage time of the transition. A detailed description of the PPS↔R transition in the converter domain of myosin VI is obtained, including the transition path, the free energy along the path, and the rates of interconversion. The methodology developed here is expected to be useful more generally in studies of conformational transitions in complex biomolecules. PMID:21361558

  9. Anomalous Thouless energy and critical statistics on the metallic side of the many-body localization transition

    NASA Astrophysics Data System (ADS)

    Bertrand, Corentin L.; García-García, Antonio M.

    2016-10-01

    We study a one-dimensional XXZ spin chain in a random field on the metallic side of the many-body localization transition by level statistics. For a fixed interaction, and intermediate disorder below the many-body localization transition, we find that, asymptotically, the number variance grows faster than linear with a disorder-dependent exponent. This is consistent with the existence of an anomalous Thouless energy in the spectrum. In noninteracting disordered metals, this is an energy scale related to the typical time for a particle to diffuse across the sample. In the interacting case, it seems related to a more intricate anomalous diffusion process. This interpretation is not fully consistent with recent claims that for intermediate disorder, level statistics are described by a plasma model with power-law decaying interactions whose number variance grows slower than linear. As disorder is further increased, still on the metallic side, the Thouless energy is gradually washed out. In the range of sizes we can explore, level statistics are scale invariant and approach Poisson statistics at the many-body localization transition. Slightly below the many-body localization transition, spectral correlations, well described by critical statistics, are quantitatively similar to those of a high-dimensional, noninteracting, disordered conductor at the Anderson transition.

  10. Energy Transition Initiative: Island Energy Snapshot - San Andres and Providencia (Fact Sheet); NREL(National Renewable Energy Laboratory)

    SciTech Connect

    2015-03-01

    This profile provides a snapshot of the energy landscape of the Archipelago of San Andres, Providencia, and Santa Catalina (unpopulated), also known as San Andres and Providencia, which is equidistant between Costa Rica and Jamaica and 775 kilometers northwest of Colombia. The archipelago is part of Colombia, though Nicaragua has also laid claim to it.

  11. Students' Meaning Making in Science: Solving Energy Resource Problems in Virtual Worlds Combined with Spreadsheets to Develop Graphs

    ERIC Educational Resources Information Center

    Krange, Ingeborg; Arnseth, Hans Christian

    2012-01-01

    The aim of this study is to scrutinize the characteristics of conceptual meaning making when students engage with virtual worlds in combination with a spreadsheet with the aim to develop graphs. We study how these tools and the representations they contain or enable students to construct serve to influence their understanding of energy resource…

  12. A life-cycle approach to technology, infrastructure, and climate policy decision making: Transitioning to plug-in hybrid electric vehicles and low-carbon electricity

    NASA Astrophysics Data System (ADS)

    Samaras, Constantine

    In order to mitigate the most severe effects of climate change, large global reductions in the current levels of anthropogenic greenhouse gas (GHG) emissions are required in this century to stabilize atmospheric carbon dioxide (CO2) concentrations at less than double pre-industrial levels. The Intergovernmental Panel on Climate Change (IPCC) fourth assessment report states that GHG emissions should be reduced to 50-80% of 2000 levels by 2050 to increase the likelihood of stabilizing atmospheric CO2 concentrations. In order to achieve the large GHG reductions by 2050 recommended by the IPCC, a fundamental shift and evolution will be required in the energy system. Because the electric power and transportation sectors represent the largest GHG emissions sources in the United States, a unique opportunity for coupling these systems via electrified transportation could achieve synergistic environmental (GHG emissions reductions) and energy security (petroleum displacement) benefits. Plug-in hybrid electric vehicles (PHEVs), which use electricity from the grid to power a portion of travel, could play a major role in reducing greenhouse gas emissions from the transport sector. However, this thesis finds that life cycle GHG emissions from PHEVs depend on the electricity source that is used to charge the battery, so meaningful GHG emissions reductions with PHEVs are conditional on low-carbon electricity sources. Power plants and their associated GHGs are long-lived, and this work argues that decisions made regarding new electricity supplies within the next ten years will affect the potential of PHEVs to play a role in a low-carbon future in the coming decades. This thesis investigates the life cycle engineering, economic, and policy decisions involved in transitioning to PHEVs and low-carbon electricity. The government has a vast array of policy options to promote low-carbon technologies, some of which have proven to be more successful than others. This thesis uses life

  13. Energy exchange between a laser beam and charged particles using inverse transition radiation and method for its use

    DOEpatents

    Kimura, Wayne D.; Romea, Richard D.; Steinhauer, Loren C.

    1998-01-01

    A method and apparatus for exchanging energy between relativistic charged particles and laser radiation using inverse diffraction radiation or inverse transition radiation. The beam of laser light is directed onto a particle beam by means of two optical elements which have apertures or foils through which the particle beam passes. The two apertures or foils are spaced by a predetermined distance of separation and the angle of interaction between the laser beam and the particle beam is set at a specific angle. The separation and angle are a function of the wavelength of the laser light and the relativistic energy of the particle beam. In a diffraction embodiment, the interaction between the laser and particle beams is determined by the diffraction effect due to the apertures in the optical elements. In a transition embodiment, the interaction between the laser and particle beams is determined by the transition effect due to pieces of foil placed in the particle beam path.

  14. Austin's Home Performance with Energy Star Program: Making a Compelling Offer to a Financial Institution Partner

    SciTech Connect

    Zimring, Mark

    2011-03-18

    Launched in 2006, over 8,700 residential energy upgrades have been completed through Austin Energy's Home Performance with Energy Star (HPwES) program. The program's lending partner, Velocity Credit Union (VCU) has originated almost 1,800 loans, totaling approximately $12.5 million. Residential energy efficiency loans are typically small, and expensive to originate and service relative to larger financing products. National lenders have been hesitant to deliver attractive loan products to this small, but growing, residential market. In response, energy efficiency programs have found ways to partner with local and regional banks, credit unions, community development finance institutions (CDFIs) and co-ops to deliver energy efficiency financing to homeowners. VCU's experience with the Austin Energy HPwES program highlights the potential benefits of energy efficiency programs to a lending partner.

  15. Conformational transitions in the calcium adenosinetriphosphatase studied by time-resolved fluorescence resonance energy transfer.

    PubMed

    Birmachu, W; Nisswandt, F L; Thomas, D D

    1989-05-01

    We have used time-resolved fluorescence to study proposed conformational transitions in the Ca-ATPase in skeletal sarcoplasmic reticulum (SR). Resonance energy transfer was used to measure distances between the binding sites of 5-[[2-[(iodoacetyl)amino]ethyl]amino]naphthalene-1-sulfonic acid (IAEDANS) and fluorescein 5-isothiocyanate (FITC) as a function of conditions proposed to affect the enzyme's conformation. When 1.0 +/- 0.15 IAEDANS is bound per Ca-ATPase, most (76 +/- 4%) of the probes have an excited-state lifetime (tau) of 18.6 +/- 0.5 ns, and the remainder have a lifetime of 2.5 +/- 0.9 ns. When FITC is bound to a specific site on each IAEDANS-labeled enzyme, most of the long-lifetime component is quenched into two short-lifetime components, indicating energy transfer that corresponds to two donor-acceptor distances. About one-third of the quenched population has a lifetime tau = 11.1 +/- 2.5 ns, corresponding to a transfer efficiency E = 0.40 +/- 0.07 and a donor-acceptor distance R1 = 52 +/- 3 A. The remaining two-thirds exhibit lifetimes in the range of 1.2-4.2 ns, corresponding to a second distance 31 A less than or equal to R2 less than or equal to 40 A. Addition of Ca2+ (in the micromolar to millimolar range), or vanadate (to produce a phosphoenzyme analogue), had no effect on the donor-acceptor distances. Addition of decavanadate results in the quenching of IAEDANS fluorescence but has no effect on the energy-transfer distance.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Metal ferrite spinel energy storage devices and methods for making and using same

    DOEpatents

    Weimer, Alan W.; Perkins, Christopher; Scheffe, Jonathan; George, Steven M.; Lichty, Paul

    2013-03-19

    1-100 nm metal ferrite spinel coatings are provided on substrates, preferably by using an atomic layer deposition process. The coatings are able to store energy such as solar energy, and to release that stored energy, via a redox reaction. The coating is first thermally or chemically reduced. The reduced coating is then oxidized in a second step to release energy and/or hydrogen, carbon monoxide or other reduced species.

  17. Metal ferrite spinel energy storage devices and methods for making and using same

    DOEpatents

    Weimer, Alan W.; Perkins, Christopher; Scheffe, Jonathan; George, Steven M.; Lichty, Paul

    2012-05-29

    1-100 nm metal ferrite spinel coatings are provided on substrates, preferably by using an atomic layer deposition process. The coatings are able to store energy such as solar energy, and to release that stored energy, via a redox reaction. The coating is first thermally or chemically reduced. The reduced coating is then oxidized in a second step to release energy and/or hydrogen, carbon monoxide or other reduced species.

  18. Flambeau River Papers Makes a Comeback with a Revised Energy Strategy

    SciTech Connect

    2010-03-10

    After the closure of the Flambeau River Papers mill in 2006, a new energy management approach has resulted in $2.6 million in annual energy savings and increased the facility's production by 11.9%. Read about Flambeau's successful energy management approach.

  19. SunShot: Making Solar Energy Cost-Competitive Throughout the United States (Fact Sheet)

    SciTech Connect

    Not Available

    2013-02-01

    The U.S. Department of Energy SunShot Initiative is designed to re-establish American technological leadership, strengthen U.S. economic competitiveness in the global clean energy race, and help America obtain a secure energy future. This fact sheet highlights the achievements of the initiative since 2010.

  20. Accurate Potential Energy Surface, Rovibrational Energy Levels, and Transitions of Ammonia C_{3v} Isotopologues: ^{14}NH_3, ^{15}NH_3, ^{14}ND_3 and ^{14}NT_3

    NASA Astrophysics Data System (ADS)

    Huang, Xinchuan; Schwenke, David W.; Lee, Timothy J.

    2009-06-01

    A further refined, global potential energy surface (PES) is computed for the C_{3v} symmetry isotopologues of ammonia, including ^{14}NH_3, ^{15}NH_3, ^{14}ND_3 and ^{14}NT_3. The refinement procedure was similar to that used in our previously reported PES, but now extends to higher J energy levels and other isotopologues. Both the diagonal Born-Oppenheimer correction and the non-adiabatic correction were included. J=0-6 rovibrational energy levels and transition frequencies of ^{14}NH_3 computed on this PES are in excellent agreement with HITRAN data. Statistics on nearly 4100 transitions and more than 1000 energy levels demonstrate the accuracy achieved by the state-of-the-art "Best Theory + Experiment" strategy. Most transition frequencies are of ±0.01-0.02 cm^{-1} accuracy. Similar accuracy has been found on ^{15}NH_3 J=0-3 rovibrational energy levels. Several transitions and energy levels in HITRAN have been identified as unreliable or suspicious, and some have been re-assigned. For ^{14}ND_3 and ^{14}NT_3, J=0-3 calculations have been performed. Agreement for pure rotation-inversion transitions is nearly perfect, with more reliable energy levels presented. On the other hand, our J=0 results suggest a re-analysis on the ^{14}ND_3 ν_1 band origin is needed. Finally, we will discuss possible future refinements leading to an even better final PES for Ammonia. X. Huang, D.W. Schwenke, and T.J. Lee, J. Chem. Phys. 129, 214304 (2008).

  1. Leveraging the water-energy-food nexus for a sustainability transition: Institutional and policy design choices in a fragmented world (Invited)

    NASA Astrophysics Data System (ADS)

    Aggarwal, R.

    2013-12-01

    Given the critical - but often subtle - feedbacks between water, energy, and food security, a nexus approach that integrates management and governance across sectors and scales is increasingly being advocated in research and policy circles. As a first step, such an approach calls for an integrated multi-disciplinary assessment of the externalities across sectors and tradeoffs involved in enhancing security in one sector on the other sectors. Recent research efforts have focused on understanding these tradeoffs, say, through estimating the energy costs of expanding irrigation for greater food security; or estimating the embodied land and water costs in increased energy production. While such efforts have increased awareness about the inter-connectedness of such issues, the fundamental question of how such an understanding influences decision-making and how it can lead to coordinated action towards a transition to more sustainable pathways still remains largely unanswered. The long legacy of sectoral organization of political and bureaucratic structures has led to a fragmentary policy and institutional landscape, on which cross-sectoral public action and coordination poses several challenges. Moreover, poorly defined property rights, imperfect or absent markets, and uncertainty about resource dynamics imply that economic signals about relative scarcity in one sector are not necessarily clear to decision makers in the other sectors. In this study, we examine these issues related to water-energy food nexus in the context of semi-arid groundwater irrigated regions of western and southern India. Using a social-ecological systems framework, we begin by characterizing some of the key inter-dependencies among food, water, and energy at the farm household, village and state level. We then examine the factors that influence decision-making at these levels, and the extent to which these decisions internalize the externalities. Specifically, we examine the role of energy

  2. Energy-management guidelines for rail-transit systems. Volume 2. Final report, 9 July 1984-30 October 1986

    SciTech Connect

    Uher, R.A.; Sharma, O.N.

    1986-09-01

    The Energy Management Guidelines Manual is organized into two separate volumes and an executive summary. Volume II contains the methodologies, analyses techniques and strategies, which can be used to achieve the goals of increased energy efficiency and lower energy cost. Examples of the application of these techniques and strategies are also included. Section 1.0 deals with energy-conservation strategies for reducing energy consumption. The role that modification of the power-rate structure plays, through rate negotiations/intervention, is discussed in Section 2.0. Section 3.0 addresses the topic of load management, which can reduce power demand, thus lowering the demand component of the electric bill. Section 4.0 presents a description of the Energy Management Model (EMM) which is a tool used to simulate traction operation and its resultant energy consumption on a rail-transit system. Section 5.0 discusses the methodologies and analytical tools necessary to conduct an energy audit on a rail transit system. The audit is an important step in identifying opportunities for energy-cost reduction.

  3. The Effect of Disorder on the Free-Energy for the Random Walk Pinning Model: Smoothing of the Phase Transition and Low Temperature Asymptotics

    NASA Astrophysics Data System (ADS)

    Berger, Quentin; Lacoin, Hubert

    2011-01-01

    We consider the continuous time version of the Random Walk Pinning Model (RWPM), studied in (Berger and Toninelli (Electron. J. Probab., to appear) and Birkner and Sun (Ann. Inst. Henri Poincaré Probab. Stat. 46:414-441, 2010; arXiv:0912.1663). Given a fixed realization of a random walk Y on ℤ d with jump rate ρ (that plays the role of the random medium), we modify the law of a random walk X on ℤ d with jump rate 1 by reweighting the paths, giving an energy reward proportional to the intersection time Lt(X,Y)=int0t {1}_{Xs=Ys} {d}s: the weight of the path under the new measure is exp ( βL t ( X, Y)), β∈ℝ. As β increases, the system exhibits a delocalization/localization transition: there is a critical value β c , such that if β> β c the two walks stick together for almost-all Y realizations. A natural question is that of disorder relevance, that is whether the quenched and annealed systems have the same behavior. In this paper we investigate how the disorder modifies the shape of the free energy curve: (1) We prove that, in dimension d≥3, the presence of disorder makes the phase transition at least of second order. This, in dimension d≥4, contrasts with the fact that the phase transition of the annealed system is of first order. (2) In any dimension, we prove that disorder modifies the low temperature asymptotic of the free energy.

  4. Electron energy-loss near-edge structures of 3d transition metal oxides recorded at high-energy resolution.

    PubMed

    Mitterbauer, C; Kothleitner, G; Grogger, W; Zandbergen, H; Freitag, B; Tiemeijer, P; Hofer, F

    2003-09-01

    Near-edge fine structures of the metal L(2,3) and O K-edges in transition metal-oxides have been studied with a transmission electron microscope equipped with a monochromator and a high-resolution imaging filter. This system enables the recording of EELS spectra with an energy resolution of 0.1eV thus providing new near-edge fine structure details which could not be observed previously by EELS in conventional TEM instruments. EELS-spectra from well-defined oxides like titanium oxide (TiO(2)), vanadium oxide (V(2)O(5)), chromium oxide (Cr(2)O(3)), iron oxide (Fe(2)O(3)), cobalt oxide (CoO) and nickel oxide (NiO) have been measured with the new system. These spectra are compared with EELS data obtained from a conventional microscope and the main spectral features are interpreted. Additionally, the use of monochromised TEMs is discussed in view of the natural line widths of K and L(2,3) edges. PMID:12871809

  5. Transitions: A Personal Perspective.

    ERIC Educational Resources Information Center

    Wood, Ann Stace

    1995-01-01

    Distinguishes between unchosen transitions (children maturing and leaving, parents aging, companies downsizing) and chosen ones (moving, divorce, marriage, career changes). Describes the steps one goes through: uneasiness, renewed energy, complaining, exploration, partial transition, and the completed transition. (JOW)

  6. Transition of the U.S. Department of Energy Fernald Closure Project (FCP) from Cleanup to Legacy Management

    SciTech Connect

    Powell, J.; Craig, J.R.; Jacobson, C.

    2006-07-01

    The Fernald Closure Project encompasses a 1,050-acre tract of land northwest of Cincinnati, Ohio. Dedicated to the production of uranium feed materials from 1952 until 1989, the site was subsequently included on the U.S. Environmental Protection Agency's National Priorities List and slated for cleanup. Except for contaminated ground water, cleanup of the site will be completed in 2006; remediation of the aquifer will continue for 20 years. Transition of the project from the U.S. Department of Energy Office of Environmental Management to the Office of Legacy Management will be effected when site cleanup is completed, surface restoration is complete, and aquifer remediation is on-going. Office of Legacy Management activities will focus on the monitoring and maintenance of the on-site disposal facility, enforcement of restrictions on site access and use, and the protection of natural and cultural resources. The Site Transition Plan, developed in accordance with Site Transition Framework guidance, identifies organizational and financial responsibilities for attaining closeout. A Transition Matrix details more than 1,000 activities necessary for site transition and allows each task to be tracked. Responsibility Transition Plans address major areas of scope to be transferred, such as records and information management, infrastructure, and environmental monitoring. Much effort has been placed on the retention of staff to perform the identified Office of Legacy Management scope. (authors)

  7. MARKAL-MACRO: A methodology for informed energy, economy and environmental decision making. Informal report

    SciTech Connect

    Goldstein, G.A.

    1995-05-16

    Since the mid-1970`s, energy system analysts have been using models to represent the complexities of interactions in energy systems to help shape policy. Since the mid-1980`s, heightened awareness has made it necessary also to consider the environmental impacts of energy policies. MARKAL is a cost-minimizing energy-environment system planning model used to explore mid- to long-term responses to different technological futures, emissions limitations, and policy scenarios. MARKAL-MACRO is an extension of MARKAL that integrates these capabilities directly with a neoclassical macroeconomic growth model. By combining bottom-up engineering and top-down macroeconomic approaches in a single modeling framework, MARKAL-MACR is able to capture the interplay between the energy system, the economy and the environment, allowing the affects on demands of endogenously determined energy prices to be explored.

  8. Development of Energy Models for Production Systems and Processes to Inform Environmentally Benign Decision-Making

    NASA Astrophysics Data System (ADS)

    Diaz-Elsayed, Nancy

    Between 2008 and 2035 global energy demand is expected to grow by 53%. While most industry-level analyses of manufacturing in the United States (U.S.) have traditionally focused on high energy consumers such as the petroleum, chemical, paper, primary metal, and food sectors, the remaining sectors account for the majority of establishments in the U.S. Specifically, of the establishments participating in the Energy Information Administration's Manufacturing Energy Consumption Survey in 2006, the non-energy intensive" sectors still consumed 4*109 GJ of energy, i.e., one-quarter of the energy consumed by the manufacturing sectors, which is enough to power 98 million homes for a year. The increasing use of renewable energy sources and the introduction of energy-efficient technologies in manufacturing operations support the advancement towards a cleaner future, but having a good understanding of how the systems and processes function can reduce the environmental burden even further. To facilitate this, methods are developed to model the energy of manufacturing across three hierarchical levels: production equipment, factory operations, and industry; these methods are used to accurately assess the current state and provide effective recommendations to further reduce energy consumption. First, the energy consumption of production equipment is characterized to provide machine operators and product designers with viable methods to estimate the environmental impact of the manufacturing phase of a product. The energy model of production equipment is tested and found to have an average accuracy of 97% for a product requiring machining with a variable material removal rate profile. However, changing the use of production equipment alone will not result in an optimal solution since machines are part of a larger system. Which machines to use, how to schedule production runs while accounting for idle time, the design of the factory layout to facilitate production, and even the

  9. Review of Life-Cycle Approaches Coupled with Data Envelopment Analysis: Launching the CFP + DEA Method for Energy Policy Making

    PubMed Central

    Vázquez-Rowe, Ian

    2015-01-01

    Life-cycle (LC) approaches play a significant role in energy policy making to determine the environmental impacts associated with the choice of energy source. Data envelopment analysis (DEA) can be combined with LC approaches to provide quantitative benchmarks that orientate the performance of energy systems towards environmental sustainability, with different implications depending on the selected LC + DEA method. The present paper examines currently available LC + DEA methods and develops a novel method combining carbon footprinting (CFP) and DEA. Thus, the CFP + DEA method is proposed, a five-step structure including data collection for multiple homogenous entities, calculation of target operating points, evaluation of current and target carbon footprints, and result interpretation. As the current context for energy policy implies an anthropocentric perspective with focus on the global warming impact of energy systems, the CFP + DEA method is foreseen to be the most consistent LC + DEA approach to provide benchmarks for energy policy making. The fact that this method relies on the definition of operating points with optimised resource intensity helps to moderate the concerns about the omission of other environmental impacts. Moreover, the CFP + DEA method benefits from CFP specifications in terms of flexibility, understanding, and reporting. PMID:25654136

  10. Review of life-cycle approaches coupled with data envelopment analysis: launching the CFP + DEA method for energy policy making.

    PubMed

    Vázquez-Rowe, Ian; Iribarren, Diego

    2015-01-01

    Life-cycle (LC) approaches play a significant role in energy policy making to determine the environmental impacts associated with the choice of energy source. Data envelopment analysis (DEA) can be combined with LC approaches to provide quantitative benchmarks that orientate the performance of energy systems towards environmental sustainability, with different implications depending on the selected LC + DEA method. The present paper examines currently available LC + DEA methods and develops a novel method combining carbon footprinting (CFP) and DEA. Thus, the CFP + DEA method is proposed, a five-step structure including data collection for multiple homogenous entities, calculation of target operating points, evaluation of current and target carbon footprints, and result interpretation. As the current context for energy policy implies an anthropocentric perspective with focus on the global warming impact of energy systems, the CFP + DEA method is foreseen to be the most consistent LC + DEA approach to provide benchmarks for energy policy making. The fact that this method relies on the definition of operating points with optimised resource intensity helps to moderate the concerns about the omission of other environmental impacts. Moreover, the CFP + DEA method benefits from CFP specifications in terms of flexibility, understanding, and reporting. PMID:25654136

  11. Review of life-cycle approaches coupled with data envelopment analysis: launching the CFP + DEA method for energy policy making.

    PubMed

    Vázquez-Rowe, Ian; Iribarren, Diego

    2015-01-01

    Life-cycle (LC) approaches play a significant role in energy policy making to determine the environmental impacts associated with the choice of energy source. Data envelopment analysis (DEA) can be combined with LC approaches to provide quantitative benchmarks that orientate the performance of energy systems towards environmental sustainability, with different implications depending on the selected LC + DEA method. The present paper examines currently available LC + DEA methods and develops a novel method combining carbon footprinting (CFP) and DEA. Thus, the CFP + DEA method is proposed, a five-step structure including data collection for multiple homogenous entities, calculation of target operating points, evaluation of current and target carbon footprints, and result interpretation. As the current context for energy policy implies an anthropocentric perspective with focus on the global warming impact of energy systems, the CFP + DEA method is foreseen to be the most consistent LC + DEA approach to provide benchmarks for energy policy making. The fact that this method relies on the definition of operating points with optimised resource intensity helps to moderate the concerns about the omission of other environmental impacts. Moreover, the CFP + DEA method benefits from CFP specifications in terms of flexibility, understanding, and reporting.

  12. "Energy is...life": Meaning making through dialogue in a tribal college physics course

    NASA Astrophysics Data System (ADS)

    Antonellis, Jessica Christel

    This research is an exploration of students' meaning making around physical concepts through connections to students' funds of knowledge. This qualitative case study, influenced by Indigenous methodologies, focused on two Native students in a tribal college introductory physics course, exploring the personal, cultural, and philosophical connections that were voiced in dialogic interactions among the students and instructor. The data were collected through audio recordings of class sessions and reflective journaling by the instructor/researcher. Analysis identified dialogues in which meaning making took place, and the funds of knowledge that students brought to bear on these dialogues. The results of the analysis of these meaning-making occasions are presented by physical concept. For both students, the cultural connections they brought in were ways for them to incorporate their out-of-class identities and to consider their cultures from a scientific perspective. The influence of the students' personal connections was just as important as that of the cultural connections; the shared classroom context was also a valuable resource in the for collaborative meaning making. Both students both enjoyed examining the philosophical and spiritual implications of physical ideas; these dialogues provided windows into students' thinking that would not have been accessible in other ways. The students also made meanings about the nature of science that meshed with their identities and created a space for them to identify as scientists, and both came to view science as part of their cultural heritage. Allowing students free reign to make connections and empowering them to make decisions about their own learning were means of encouraging students to develop meaningful conceptual understanding. By investigating the meanings students made around physical content, we can learn about what motivates them, what is important to them, and potentially how to structure curricula that will

  13. Decision-making by a soaring bird: time, energy and risk considerations at different spatio-temporal scales.

    PubMed

    Harel, Roi; Duriez, Olivier; Spiegel, Orr; Fluhr, Julie; Horvitz, Nir; Getz, Wayne M; Bouten, Willem; Sarrazin, François; Hatzofe, Ohad; Nathan, Ran

    2016-09-26

    Natural selection theory suggests that mobile animals trade off time, energy and risk costs with food, safety and other pay-offs obtained by movement. We examined how birds make movement decisions by integrating aspects of flight biomechanics, movement ecology and behaviour in a hierarchical framework investigating flight track variation across several spatio-temporal scales. Using extensive global positioning system and accelerometer data from Eurasian griffon vultures (Gyps fulvus) in Israel and France, we examined soaring-gliding decision-making by comparing inbound versus outbound flights (to or from a central roost, respectively), and these (and other) home-range foraging movements (up to 300 km) versus long-range movements (longer than 300 km). We found that long-range movements and inbound flights have similar features compared with their counterparts: individuals reduced journey time by performing more efficient soaring-gliding flight, reduced energy expenditure by flapping less and were more risk-prone by gliding more steeply between thermals. Age, breeding status, wind conditions and flight altitude (but not sex) affected time and energy prioritization during flights. We therefore suggest that individuals facing time, energy and risk trade-offs during movements make similar decisions across a broad range of ecological contexts and spatial scales, presumably owing to similarity in the uncertainty about movement outcomes.This article is part of the themed issue 'Moving in a moving medium: new perspectives on flight'. PMID:27528787

  14. Correlation functions in liquids and crystals: free-energy functional and liquid-to-crystal transition.

    PubMed

    Bharadwaj, Atul S; Singh, Swarn L; Singh, Yashwant

    2013-08-01

    A free-energy functional for a crystal that contains both the symmetry-conserved and symmetry-broken parts of the direct pair-correlation function has been used to investigate the crystallization of fluids in three dimensions. The symmetry-broken part of the direct pair-correlation function has been calculated using a series in ascending powers of the order parameters and which contains three- and higher-body direct correlation functions of the isotropic phase. It is shown that a very accurate description of freezing transitions for a wide class of potentials is found by considering the first two terms of this series. The results found for freezing parameters including the structure of the frozen phase for fluids interacting via the inverse power potential u(r)=ε(σ/r)(n) for n ranging from 4 to ∞ are in very good agreement with simulation results. It is found that for n>6.5 the fluid freezes into a face-centered cubic (fcc) structure while for n≤6 the body-centered cubic (bcc) structure is preferred. The fluid-bcc-fcc triple point is found to be at 1/n=0.158, which is in good agreement with simulation result. PMID:24032780

  15. Theoretical equilibrium geometry, vibrational frequencies and the first electronic transition energy of HCC

    NASA Astrophysics Data System (ADS)

    Fogarasi, Géza; Boggs, James E.; Pulay, Péter

    Ab initio calculations with the 6-311 G** basis set and all single and double excitations in the CI treatment have been carried out to determine the structure of the HCC radical. The theoretical geometry of R(CC) = 1·209, r(CH) = 1·067 Å (or 1·205 and 1·063, respectively, if corrected for residual errors) is in excellent accordance with the experimental rotational constant. The calculated harmonic vibrational frequencies are v1 ⋍ 3450, v2 ⋍ 540 and v3 ⋍ 2040 cm-1. An extremely low energy around 2000 cm-1 is obtained for the first electronic transition A2II ← X 2∑. Results for the excited state are also given. The theoretical vibrational frequencies, with all possible errors taken into account, are inconsistent with the accepted interpretations of the few experimental results. It is shown, however, that a complete reinterpretation of the spectroscopic observations is possible, by which the present calculations fit with the recent gas phase infrared laser spectroscopic data but remain in definite contradiction with the infrared matrix results.

  16. Study of electron transition energies between anions and cations in spinel ferrites using differential UV-vis absorption spectra

    NASA Astrophysics Data System (ADS)

    Xue, L. C.; Wu, L. Q.; Li, S. Q.; Li, Z. Z.; Tang, G. D.; Qi, W. H.; Ge, X. S.; Ding, L. L.

    2016-07-01

    It is very important to determine electron transition energies (Etr) between anions and different cations in order to understand the electrical transport and magnetic properties of a material. Many authors have analyzed UV-vis absorption spectra using the curve (αhν)2 vs E, where α is the absorption coefficient and E(=hν) is the photon energy. Such an approach can give only two band gap energies for spinel ferrites. In this paper, using differential UV-vis absorption spectra, dα/dE vs E, we have obtained electron transition energies (Etr) between the anions and cations, Fe2+ and Fe3+ at the (A) and [B] sites and Ni2+ at the [B] sites for the (A)[B]2O4 spinel ferrite samples CoxNi0.7-xFe2.3O4 (0.0≤x≤0.3), CrxNi0.7Fe2.3-xO4 (0.0≤x≤0.3) and Fe3O4. We suggest that the differential UV-vis absorption spectra should be accepted as a general analysis method for determining electron transition energies between anions and cations.

  17. Land use impacts of low-carbon energy system transition - the case of UK bioenergy deployment under the Carbon Plan

    NASA Astrophysics Data System (ADS)

    Konadu, D. D.; Sobral Mourao, Z.; Lupton, R.; Skelton, S.

    2015-12-01

    The UK Department of Energy and Climate Change has developed four low-carbon energy transition pathways - the Carbon Plan - towards achieving the legally binding 80% territorial greenhouse gas emissions reduction, stipulated in the 2008 Climate Change Act by 2050. All the pathways require increase in bioenergy deployment, of which a significant amount could be indigenously sourced from crops. But will increased domestic production of energy crops conflict with other land use and ecosystem priorities? To address this question, a coupled analysis of the four energy transition pathways and land use has been developed using an integrated resource accounting platform called ForeseerTM. The two systems are connected by the bioenergy component, and are projected forward in time to 2050, under different scenarios of energy crop composition and yield, and accounting for various constraints on land use for agriculture and ecosystem services. The results show between 7 and 61% of UK agricultural land could be required to meet bioenergy deployment projections under different combinations of crop yield and compositions for the transition pathways. This could result in competition for land for food production and other socio-economic and ecological land uses. Consequently, the potential role of bioenergy in achieving UK emissions reduction targets may face significant deployment challenges.

  18. Developing and Transitioning Numerical Air Quality Models to Improve Air Quality and Public Health Decision-Making in El Salvador and Costa Rica As Part of the Servir Applied Sciences Team

    NASA Astrophysics Data System (ADS)

    Thomas, A.; Huff, A. K.; Gomori, S. G.; Sadoff, N.

    2014-12-01

    In order to enhance the capacity for air quality modeling and improve air quality monitoring and management in the SERVIR Mesoamerica region, members of SERVIR's Applied Sciences Team (AST) are developing national numerical air quality models for El Salvador and Costa Rica. We are working with stakeholders from the El Salvador Ministry of the Environment and Natural Resources (MARN); National University of Costa Rica (UNA); the Costa Rica Ministry of the Environment, Energy, and Telecommunications (MINAET); and Costa Rica National Meteorological Institute (IMN), who are leaders in air quality monitoring and management in the Mesoamerica region. Focusing initially on these institutions will build sustainability in regional modeling activities by developing air quality modeling capability that can be shared with other countries in Mesoamerica. The air quality models are based on the Community Multi-scale Air Quality (CMAQ) model and incorporate meteorological inputs from the Weather Research and Forecasting (WRF) model, as well as national emissions inventories from El Salvador and Costa Rica. The models are being optimized for urban air quality, which is a priority of decision-makers in Mesoamerica. Once experimental versions of the modeling systems are complete, they will be transitioned to servers run by stakeholders in El Salvador and Costa Rica. The numerical air quality models will provide decision support for stakeholders to identify 1) high-priority areas for expanding national ambient air monitoring networks, 2) needed revisions to national air quality regulations, and 3) gaps in national emissions inventories. This project illustrates SERVIR's goal of the transition of science to support decision-making through capacity building in Mesoamerica, and it aligns with the Group on Earth Observations' health societal benefit theme. This presentation will describe technical aspects of the development of the models and outline key steps in our successful

  19. ORAL ISSUE OF THE JOURNAL "USPEKHI FIZICHESKIKH NAUK": Transition radiation: scientific implications and applications in high-energy physics

    NASA Astrophysics Data System (ADS)

    Denisov, Sergei P.

    2007-04-01

    In their pioneering work on transition radiation, Ginzburg and Frank showed for the first time that a charge may radiate electromagnetic waves not only because of its accelerated motion but also because of time variation of the phase velocity of electromagnetic waves in the ambient medium. This result is of very general importance for physics. For example, a charge at rest can radiate in a nonstationary medium. Transition radiation is widely used in high-energy particle detectors, mainly for identification of ultrarelativistic electrons in accelerator and collider experiments.

  20. Binding energies and spatial structures of small carrier complexes in monolayer transition-metal dichalcogenides via diffusion Monte Carlo

    DOE PAGES

    Mayers, Matthew Z.; Berkelbach, Timothy C.; Hybertsen, Mark S.; Reichman, David R.

    2015-10-09

    Ground-state diffusion Monte Carlo is used to investigate the binding energies and intercarrier radial probability distributions of excitons, trions, and biexcitons in a variety of two-dimensional transition-metal dichalcogenide materials. We compare these results to approximate variational calculations, as well as to analogous Monte Carlo calculations performed with simplified carrier interaction potentials. Our results highlight the successes and failures of approximate approaches as well as the physical features that determine the stability of small carrier complexes in monolayer transition-metal dichalcogenide materials. In conclusion, we discuss points of agreement and disagreement with recent experiments.

  1. Interactive computer simulation of dairy farm systems as a method for making energy management decisions

    SciTech Connect

    Hewett, E.J. III

    1983-01-01

    To facilitate management decisions an analytical model was developed to predict energy and labor requirements and costs for milking and feed handling systems. The Dairy Farm Simulation Model was based on detailed time and motion studies, and energy audits of 21 dairy farms in Michigan. Data included labor hours and energy consumption per month for each operation required for milking and feed handling and charges based on Detroit Edison electrical rate schedules. The result of optimizing the electrical rate charges for simulated milking systems is indicated by the Time-of-Day Rate Schedule which provides the lowest cost to farm operators willing to adjust milking times. Simulation of mobile and stationary feeding systems for six herd sizes includes calculations of capital investment and operating costs in addition to labor and energy cost. Results indicate that mobile systems required a lower investment cost while stationary systems realize lower energy costs. Labor requirements per cow decreased as herd size increased for mobile systems, but remained the same for stationary systems regardless of herd size. The energy required to operate each system, based on the number of oil barrel equivalents, indicates the stationary system required less energy for herd sizes up to and including 150 cows, while mobile systems indicate a lower energy requirement for herd sizes greater than 150 cows. In general, no single system emerged as the best, rather it depended on the operator's personal preference.

  2. Trap the Energy of the Sun. What We Make. Science and Technology Education in Philippine Society.

    ERIC Educational Resources Information Center

    Philippines Univ., Quezon City. Inst. for Science and Mathematics Education Development.

    Filipino scientists and inventors have tried many ways of using solar energy. One simple device, made of wood and ordinary plastic sheets, traps solar energy to dry palay grains and other agricultural products. In this module, information and activities are provided to help students: (1) learn the advantages of using a solar crop dryer over direct…

  3. Low energy cyclotron production of multivalent transition metals for PET imaging and therapy

    NASA Astrophysics Data System (ADS)

    Avila-Rodriguez, Miguel Angel

    Recent advances in high-resolution tomographs for small animals require the production of nonconventional long-lived positron emitters to label novel radiopharmaceuticals for PET-based molecular imaging. Radioisotopes with an appropriate half life to match the kinetics of slow biological processes will allow to researchers to study the phamacokinetics of PET ligands over several hours, or even days, on the same animal, with the injection of a single dose. In addition, radionuclides with a suitable half life can potentially be distributed from a central production site making them available in PET facilities that lack an in-house cyclotron. In the last few years there has been a growing interest in the use of PET ligands labeled with radiometals, particularly isotopes of copper, yttrium and zirconium. Future clinical applications of these tracers will require them to be produced reliably and efficiently. This thesis work deals with implementing and optimizing the production of the multivalent transition metals 61,64Cu, 86Y and 89Zr for molecular PET imaging and therapy. Our findings in the production of these radionuclides at high specific activity on an 11 MeV proton-only cyclotron are presented. Local applications of these tracers, including Cu-ATSM for in vivo quantification of hypoxia, synthesis of targeted radiopharmaceuticals using activated esters of DOTA, and a novel development of positron emitting resin microspheres, are also be discussed. As a result of this thesis work, metallic radionuclides are now efficiently produced on a weekly basis in sufficient quality and quantity for collaborating scientists at UW-Madison and external users in other Universities across the country.

  4. A Critical Compilation of Energy Levels, Spectral Lines, and Transition Probabilities of Singly Ionized Silver, Ag II

    PubMed Central

    Kramida, Alexander

    2013-01-01

    All available experimental measurements of the spectrum of the Ag+ ion are critically reviewed. Systematic shifts are removed from the measured wavelengths. The compiled list of critically evaluated wavelengths is used to derive a comprehensive list of energy levels with well-defined uncertainties. Eigenvector compositions and level designations are found in two alternate coupling schemes. Some of the older work is found to be incorrect. A revised value of the ionization energy, 173283(7) cm−1, equivalent to 21.4844(8) eV, is derived from the new energy levels. A set of critically evaluated transition probabilities is given. PMID:26401429

  5. Transition energies and magnetic properties of a neutral donor complex in a Gaussian GaAs quantum dot

    NASA Astrophysics Data System (ADS)

    Boda, Aalu; Chatterjee, Ashok

    2016-09-01

    The problem of a neutral hydrogenic donor (D0) centre located at the centre of a GaAs quantum dot with Gaussian confinement is studied in the presence of an external magnetic field. The ground and the first excited state energies and the corresponding binding energies are obtained as functions of the potential strength, quantum dot radius and the magnetic field using a variational method. It is suggested that the first excited state of the D0 centre is bound for sufficiently strong confinement potential. The 1 s - 2p- transition energy and the magnetic susceptibilities for the ground and the first excited states are also determined.

  6. Radiative and nonradiative exciton energy transfer in monolayers of two-dimensional group-VI transition metal dichalcogenides

    NASA Astrophysics Data System (ADS)

    Manolatou, Christina; Wang, Haining; Chan, Weimin; Tiwari, Sandip; Rana, Farhan

    2016-04-01

    We present results on the rates of interlayer energy transfer between excitons in monolayers of two-dimensional group-VI transition metal dichalcogenides (TMDs). We consider both radiative (mediated by real photons) and nonradiative (mediated by virtual photons) mechanisms of energy transfer using a unified Green's function approach that takes into account modification of the exciton energy dispersions as a result of interactions. The large optical oscillator strengths associated with excitons in TMDs result in very fast energy transfer rates. The energy transfer times depend on the exciton momentum, exciton linewidth, and the interlayer separation and can range from values less than 100 femtoseconds to more than tens of picoseconds. Whereas inside the light cone the energy transfer rates of longitudinal and transverse excitons are comparable, outside the light cone the energy transfer rates of longitudinal excitons far exceed those of transverse excitons. Average energy transfer times for a thermal ensemble of longitudinal and transverse excitons is temperature dependent and can be smaller than a picosecond at room temperature for interlayer separations smaller than 10 nm. Energy transfer times of localized excitons range from values less than a picosecond to several tens of picoseconds. When the exciton scattering and dephasing rates are small, energy transfer dynamics exhibit coherent oscillations. Our results show that electromagnetic interlayer energy transfer can be an efficient mechanism for energy exchange between TMD monolayers.

  7. "Energy Is...life": Meaning Making through Dialogue in a Tribal College Physics Course

    ERIC Educational Resources Information Center

    Antonellis, Jessica Christel

    2013-01-01

    This research is an exploration of students' meaning making around physical concepts through connections to students' funds of knowledge. This qualitative case study, influenced by Indigenous methodologies, focused on two Native students in a tribal college introductory physics course, exploring the personal, cultural, and philosophical…

  8. Assessment of New Approaches in Geothermal Exploration Decision Making; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Akar, S.; Young, K. R.

    2015-05-11

    This poster describes the findings in a related paper and information gleaned from the project. The aim of the project is to develop a methodology for more objective geothermal decision making, including more solid go/no-go decisions at specific points in the process, and to reduce subjectivity and increase reproducibility in the future.

  9. Using all of the Energy from the Sun to Make Power

    SciTech Connect

    Dapkus, P. Daniel; Povinelli, Michelle

    2013-07-18

    Representing the Center for Energy Nanoscience (CEN), this document is one of the entries in the Ten Hundred and One Word Challenge and was awarded "Overall Winner Runner-up." As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE: energy. The mission of the CEN is to explore the light absorption and emission in organic and nanostructure materials and their hybrids for solar energy conversion and solid state lighting.

  10. Energy and the environment; application of geosciences to decision-making

    USGS Publications Warehouse

    Carter, Lorna M.

    1995-01-01

    This volume contains 67 extended abstracts that summarize some of the oral and poster presentations of the tenth annual V. E. McKelvey forum on mineral and energy resources, held in Washington, D.C., Feb. 13-17, 1995. The focus is on our energy resources and the environment, new research techniques, and cooperative efforts between the USGS and industry, State and Federal agencies, universities, and other countries.

  11. Considerations for Solar Energy Technologies to Make Progress Towards Grid Price Parity

    SciTech Connect

    Woodhouse, Michael; Fu, Ran; Chung, Donald; Horowitz, Kelsey; Remo, Timothy; Feldman, David; Margolis, Robert

    2015-11-07

    In this seminar the component costs for solar photovoltaics module and system prices will be highlighted. As a basis for comparison to other renewable and traditional energy options, the metric of focus will be total lifecycle cost-of-energy (LCOE). Several innovations to traditional photovoltaics technologies (including crystalline silicon, CdTe, and CIGS) and developing technologies (including organics and perovskites) that may close the gaps in LCOE will be discussed.

  12. Reducing Subjectivity in Geothermal Exploration Decision Making (Presentation); NREL(National Renewable Energy Laboratory)

    SciTech Connect

    Akar, S.; Young, K.

    2015-01-01

    Geothermal exploration projects have a significant amount of risk associated with uncertainties encountered in the discovery of the geothermal resource. Two of the largest challenges for increased geothermal deployment are 1) understanding when and how to proceed in an exploration program, and 2) when to walk away from a site. Current methodologies for exploration decision-making are formulatedby subjective expert opinion which can be incorrectly biased by expertise (e.g. geochemistry, geophysics), geographic location of focus, and the assumed conceptual model. The aim of this project is to develop a methodology for more objective geothermal exploration decision making at a given location, including go/no-go decision points to help developers and investors decide when to give up on alocation. In this scope, two different approaches are investigated: 1) value of information analysis (VOIA) which is used for evaluating and quantifying the value of a data before they are purchased, and 2) enthalpy-based exploration targeting based on reservoir size, temperature gradient estimates, and internal rate of return (IRR). The first approach, VOIA, aims to identify the value of aparticular data when making decisions with an uncertain outcome. This approach targets the pre-drilling phase of exploration. These estimated VOIs are highly affected by the size of the project and still have a high degree of subjectivity in assignment of probabilities. The second approach, exploration targeting, is focused on decision making during the drilling phase. It starts with a basicgeothermal project definition that includes target and minimum required production capacity and initial budgeting for exploration phases. Then, it uses average temperature gradient, reservoir temperature estimates, and production capacity to define targets and go/no-go limits. The decision analysis in this approach is based on achieving a minimum IRR at each phase of the project. This secondapproach was determined

  13. From the lab to the marketplace: Making America`s buildings more energy efficient

    SciTech Connect

    1995-06-01

    Since the mid 1970s, DOE has invested some $70 million in research and development at Lawrence Berkeley Laboratory (LBL) for development of advanced energy-efficient building technologies, software, and standards. That investment has helped spawn a $2.4-billion U.S. market for key products-energy-efficient lighting and advanced window coatings-and efficiency standards for residential equipment and computerized tools for more efficient building design. By 1993 DOE`s initial investment had reduced consumers` energy bills by an estimated $5 billion ($1.3 billion in 1993 alone). By 2015 we estimate that the products of that investment will save consumers $16 billion annually. LBL research partnerships address a host of other building technology issues as well-building technology issues whose economic benefits are less easy to quantify but whose overall worth is equally important. We analyze public policy issues such as the role of efficiency options as a mitigation strategy for global climate change. We develop planning and demand-management methodologies for electric and gas utilities. We identify technologies and analytical methods for improving human comfort and the quality of indoor air. We contribute to the information superhighway. We focus on the special problems and opportunities presented by energy use in the public sector. And we do all these things at the local, national, and international levels. At LBL, we are part of the multi-laboratory, interdisciplinary approach to building technology research supported by DOE`s Office of Energy Efficiency and Renewable Energy. We also participate in buildings-related research supported by DOE`s Office of Health and Environmental Research, other federal agencies, and industry. This document describes LBL`s role within this wider effort.

  14. From the lab to the marketplace: Making America`s buildings more energy efficient

    SciTech Connect

    1995-01-01

    Since the mid 1970s, DOE has invested some $70 million in research and development at Lawrence Berkeley Laboratory (LBL) for energy-efficiency studies of advanced building technologies. That investment has helped spawn a $2.4-billion US market for key products -- energy-efficient lighting and advanced window coatings -- and efficiency standards for residential equipment and computerized tools for more efficient building design. By 1993 DOE`s initial investment had reduced consumers` energy bills by an estimated $5 billion ($1.3 billion in 1993 alone). By 2015 the authors estimate that the products of that investment will save consumers $16 billion annually. But LBL research partnerships address a host of other building technology issues as well-building technology issues whose economic benefits are less easy to quantify but whose overall worth is equally important. They analyze public policy issues such as the role of efficiency options as a mitigation strategy for global climate change. They develop planning and demand-management methodologies for electric and gas utilities. They identify technologies and analytical methods for improving human comfort and the quality of indoor air. They contribute to the information superhighway. They focus on the special problems and opportunities presented by energy use in the public sector. And they do all these things at the local, national, and international levels. At LBL, they are part of the multi-laboratory, interdisciplinary approach to building technology research supported by DOE`s Office of Energy Efficiency and Renewable Energy. They also participate in buildings-related research supported by DOE`s Office of Health and Environmental Research, other federal agencies, and industry. This document describes LBL`s role within this wider effort.

  15. Progress in making hot dry rock geothermal energy a viable renewable energy resource for America in the 21. century

    SciTech Connect

    Duchane, D.V.

    1996-01-01

    An enormous geothermal energy resource exists in the form of rock at depth that is hot but essentially dry. For more than two decades, work has been underway at the Los Alamos National Laboratory to develop and demonstrate the technology to transport the energy in hot dry rock (HDR) to the surface for practical use. During the 1980`s, the world`s largest, deepest and hottest HDR reservoir was created at the Fenton Hill HDR test facility in northern New Mexico. The reservoir is centered in rock at a temperature of about 460 F at a depth of about 11,400 ft. After mating the reservoir to a fully automated surface plant, heat was mined at Fenton Hill for a total period of almost a year in a series of flow tests conducted between 1992 and 1995. These tests addressed the major questions regarding the viability of long-term energy extraction from HDR. The steady-state flow tests at Fenton Hill showed that energy can be produced from an HDR reservoir on a routine basis and that there are no major technical obstacles to implementation of this heat mining technology. Additional brief special flow tests also demonstrated that the energy output from HDR systems can be rapidly increased in a controlled manner to meet sudden changes in power demand.

  16. Nuclear Energy R&D Imperative 3: Enable a Transition Away from Fossil Fuel in the Transportation and Industrial Sectors

    SciTech Connect

    David Petti; J. Stephen Herring

    2010-03-01

    As described in the Department of Energy Office of Nuclear Energy’s Nuclear Energy R&D Roadmap, nuclear energy can play a significant role in supplying energy for a growing economy while reducing both our dependence on foreign energy supplies and emissions from the burning of fossil fuels. The industrial and transportation sectors are responsible for more than half of the greenhouse gas emissions in the U.S., and imported oil supplies 70% of the energy used in the transportation sector. It is therefore important to examine the various ways nuclear energy can facilitate a transition away from fossil fuels to secure environmentally sustainable production and use of energy in the transportation and manufacturing industry sectors. Imperative 3 of the Nuclear Energy R&D Roadmap, entitled “Enable a Transition Away from Fossil Fuels by Producing Process Heat for use in the Transportation and Industrial Sectors”, addresses this need. This document presents an Implementation Plan for R&D efforts related to this imperative. The expanded use of nuclear energy beyond the electrical grid will contribute significantly to overcoming the three inter-linked energy challenges facing U.S. industry: the rising and volatile prices for premium fossil fuels such as oil and natural gas, dependence on foreign sources for these fuels, and the risks of climate change resulting from carbon emissions. Nuclear energy could be used in the industrial and transportation sectors to: • Generate high temperature process heat and electricity to serve industrial needs including the production of chemical feedstocks for use in manufacturing premium fuels and fertilizer products, • Produce hydrogen for industrial processes and transportation fuels, and • Provide clean water for human consumption by desalination and promote wastewater treatment using low-grade nuclear heat as a useful additional benefit. Opening new avenues for nuclear energy will significantly enhance our nation’s energy

  17. Exact versus Taylor-expanded energy density in the study of the neutron star crust-core transition

    NASA Astrophysics Data System (ADS)

    Routray, T. R.; Viñas, X.; Basu, D. N.; Pattnaik, S. P.; Centelles, M.; Robledo, L. B.; Behera, B.

    2016-10-01

    The importance of the fourth and higher order terms in the Taylor series expansion of energy of isospin asymmetric nuclear matter in studies of the neutron star crust-core phase transition is investigated using the finite-range simple effective interaction. Analytic expressions for the evaluation of the second and fourth order derivative terms in the Taylor series expansion for any general finite-range interaction of Yukawa, exponential or Gaussian form have been obtained. The effect of the nuclear matter incompressibility, symmetry energy and slope parameters on the predictions for the crust-core transition density is examined. The crustal moment of inertia is calculated and the prediction for the radius of the Vela pulsar is analyzed using different equations of state.

  18. Making the Most of Your Energy Dollars in Home Heating & Cooling. NBS Consumer Information Series 8.

    ERIC Educational Resources Information Center

    Jacobs, Madeleine; Petersen, Stephen R.

    This pamphlet is a homeowner's guide to home weatherization. It provides a step-by-step energy audit that anyone can use to help determine the insulation needs of their home. This is not a "how-to-do-it" booklet, but is a guide by which homeowners can determine the best combination of improvements for their house, climate, and fuel costs. Provided…

  19. Becoming allies: Combining social science and technological perspectives to improve energy research and policy making

    SciTech Connect

    Diamond, Rick; Moezzi, Mithra

    2002-07-01

    Within the energy research community, social sciences tends to be viewed fairly narrowly, often as simply a marketing tool to change the behavior of consumers and decision makers, and to ''attack market barriers''. As we see it, social sciences, which draws on sociology, psychology, political science, business administration, and other academic disciplines, is capable of far more. A social science perspective can re-align questions in ways that can lead to the development of technologies and technology policy that are much stronger and potentially more successful than they would be otherwise. In most energy policies governing commercial buildings, the prevailing R and D directives are firmly rooted in a technology framework, one that is generally more quantitative and evaluative than that fostered by the social sciences. To illustrate how social science thinking would approach the goal of achieving high energy performance in the commercial building sector, they focus on the US Department of Energy's Roadmap for commercial buildings (DOE 2000) as a starting point. By ''deconstructing'' the four strategies provided by the Roadmap, they set the stage for proposing a closer partnership between advocates of technology-based and social science-based approaches.

  20. Building Student Awareness of Societal Decision-Making Challenges about Energy through the Study of Earth System Data and Innovations in Energy-Related Materials Research

    NASA Astrophysics Data System (ADS)

    Zalles, D. R.; Acker, J. G.; Berding, M.

    2014-12-01

    Energy literacy requires knowledge about the trade-offs inherent in energy alternatives, about how humans use energy and have choices in how much energy to use, and about what changes to the Earth system are occurring from energy uses. It also requires collaborative decision-making skills coupled with awareness about what values we bring to the table as we negotiate solutions that serve both personal needs and the common good. Coming up with a notion of the common good requires delineating how environmental crises occurring in other parts of the world compare to our own. We also need to understand criteria for judging what might be viable solutions. This presentation describes work that SRI International is carrying out to meet these awareness-building needs. SRI educational researchers created a curriculum that immerses students in studying regional climate change data about California in comparison to global climate change. Students ponder solution energy-related strategies and impact analyses. The curriculum will be described, as will a collaboration between SRI educational researchers and materials scientists. The scientists are designing and testing technologies for producing biofuels and solar power, and for sequestering carbon from coal fired power plants. As they apply principles of science and engineering to test materials intended to meet these energy challenges, they understand that even if the tests prove successful, if there is not economic feasibility or environmental advantage, the technology may not stand as a viable solution. This educator-scientist team is using the Essential Energy Principles and Next Generation Science Standards to articulate milestones along a trajectory of energy learning. The trajectory starts with simple understandings of what energy is and what constitute our energy challenges. It ends with more the types of more sophisticated understandings needed for designing and testing energy technology solutions.

  1. Free-end adaptive nudged elastic band method for locating transition states in minimum energy path calculation.

    PubMed

    Zhang, Jiayong; Zhang, Hongwu; Ye, Hongfei; Zheng, Yonggang

    2016-09-01

    A free-end adaptive nudged elastic band (FEA-NEB) method is presented for finding transition states on minimum energy paths, where the energy barrier is very narrow compared to the whole paths. The previously proposed free-end nudged elastic band method may suffer from convergence problems because of the kinks arising on the elastic band if the initial elastic band is far from the minimum energy path and weak springs are adopted. We analyze the origin of the formation of kinks and present an improved free-end algorithm to avoid the convergence problem. Moreover, by coupling the improved free-end algorithm and an adaptive strategy, we develop a FEA-NEB method to accurately locate the transition state with the elastic band cut off repeatedly and the density of images near the transition state increased. Several representative numerical examples, including the dislocation nucleation in a penta-twinned nanowire, the twin boundary migration under a shear stress, and the cross-slip of screw dislocation in face-centered cubic metals, are investigated by using the FEA-NEB method. Numerical results demonstrate both the stability and efficiency of the proposed method. PMID:27608986

  2. High current density ion beam obtained by a transition to a highly focused state in extremely low-energy region

    SciTech Connect

    Hirano, Y. E-mail: hirano.yoichi@phys.cst.nihon-u.ac.jp; Kiyama, S.; Koguchi, H.; Fujiwara, Y.; Sakakita, H.

    2015-11-15

    A high current density (≈3 mA/cm{sup 2}) hydrogen ion beam source operating in an extremely low-energy region (E{sub ib} ≈ 150–200 eV) has been realized by using a transition to a highly focused state, where the beam is extracted from the ion source chamber through three concave electrodes with nominal focal lengths of ≈350 mm. The transition occurs when the beam energy exceeds a threshold value between 145 and 170 eV. Low-level hysteresis is observed in the transition when E{sub ib} is being reduced. The radial profiles of the ion beam current density and the low temperature ion current density can be obtained separately using a Faraday cup with a grid in front. The measured profiles confirm that more than a half of the extracted beam ions reaches the target plate with a good focusing profile with a full width at half maximum of ≈3 cm. Estimation of the particle balances in beam ions, the slow ions, and the electrons indicates the possibility that the secondary electron emission from the target plate and electron impact ionization of hydrogen may play roles as particle sources in this extremely low-energy beam after the compensation of beam ion space charge.

  3. Free-end adaptive nudged elastic band method for locating transition states in minimum energy path calculation

    NASA Astrophysics Data System (ADS)

    Zhang, Jiayong; Zhang, Hongwu; Ye, Hongfei; Zheng, Yonggang

    2016-09-01

    A free-end adaptive nudged elastic band (FEA-NEB) method is presented for finding transition states on minimum energy paths, where the energy barrier is very narrow compared to the whole paths. The previously proposed free-end nudged elastic band method may suffer from convergence problems because of the kinks arising on the elastic band if the initial elastic band is far from the minimum energy path and weak springs are adopted. We analyze the origin of the formation of kinks and present an improved free-end algorithm to avoid the convergence problem. Moreover, by coupling the improved free-end algorithm and an adaptive strategy, we develop a FEA-NEB method to accurately locate the transition state with the elastic band cut off repeatedly and the density of images near the transition state increased. Several representative numerical examples, including the dislocation nucleation in a penta-twinned nanowire, the twin boundary migration under a shear stress, and the cross-slip of screw dislocation in face-centered cubic metals, are investigated by using the FEA-NEB method. Numerical results demonstrate both the stability and efficiency of the proposed method.

  4. Free-end adaptive nudged elastic band method for locating transition states in minimum energy path calculation.

    PubMed

    Zhang, Jiayong; Zhang, Hongwu; Ye, Hongfei; Zheng, Yonggang

    2016-09-01

    A free-end adaptive nudged elastic band (FEA-NEB) method is presented for finding transition states on minimum energy paths, where the energy barrier is very narrow compared to the whole paths. The previously proposed free-end nudged elastic band method may suffer from convergence problems because of the kinks arising on the elastic band if the initial elastic band is far from the minimum energy path and weak springs are adopted. We analyze the origin of the formation of kinks and present an improved free-end algorithm to avoid the convergence problem. Moreover, by coupling the improved free-end algorithm and an adaptive strategy, we develop a FEA-NEB method to accurately locate the transition state with the elastic band cut off repeatedly and the density of images near the transition state increased. Several representative numerical examples, including the dislocation nucleation in a penta-twinned nanowire, the twin boundary migration under a shear stress, and the cross-slip of screw dislocation in face-centered cubic metals, are investigated by using the FEA-NEB method. Numerical results demonstrate both the stability and efficiency of the proposed method.

  5. Signature of a continuous quantum phase transition in non-equilibrium energy absorption: Footprints of criticality on higher excited states

    PubMed Central

    Bhattacharyya, Sirshendu; Dasgupta, Subinay; Das, Arnab

    2015-01-01

    Understanding phase transitions in quantum matters constitutes a significant part of present day condensed matter physics. Quantum phase transitions concern ground state properties of many-body systems, and hence their signatures are expected to be pronounced in low-energy states. Here we report signature of a quantum critical point manifested in strongly out-of-equilibrium states with finite energy density with respect to the ground state and extensive (subsystem) entanglement entropy, generated by an external pulse. These non-equilibrium states are evidently completely disordered (e.g., paramagnetic in case of a magnetic ordering transition). The pulse is applied by switching a coupling of the Hamiltonian from an initial value (λI) to a final value (λF) for sufficiently long time and back again. The signature appears as non-analyticities (kinks) in the energy absorbed by the system from the pulse as a function of λF at critical-points (i.e., at values of λF corresponding to static critical-points of the system). As one excites higher and higher eigenstates of the final Hamiltonian H(λF) by increasing the pulse height , the non-analyticity grows stronger monotonically with it. This implies adding contributions from higher eigenstates help magnifying the non-analyticity, indicating strong imprint of the critical-point on them. Our findings are grounded on exact analytical results derived for Ising and XY chains in transverse field. PMID:26568306

  6. High current density ion beam obtained by a transition to a highly focused state in extremely low-energy region.

    PubMed

    Hirano, Y; Kiyama, S; Fujiwara, Y; Koguchi, H; Sakakita, H

    2015-11-01

    A high current density (≈3 mA/cm(2)) hydrogen ion beam source operating in an extremely low-energy region (E(ib) ≈ 150-200 eV) has been realized by using a transition to a highly focused state, where the beam is extracted from the ion source chamber through three concave electrodes with nominal focal lengths of ≈350 mm. The transition occurs when the beam energy exceeds a threshold value between 145 and 170 eV. Low-level hysteresis is observed in the transition when E(ib) is being reduced. The radial profiles of the ion beam current density and the low temperature ion current density can be obtained separately using a Faraday cup with a grid in front. The measured profiles confirm that more than a half of the extracted beam ions reaches the target plate with a good focusing profile with a full width at half maximum of ≈3 cm. Estimation of the particle balances in beam ions, the slow ions, and the electrons indicates the possibility that the secondary electron emission from the target plate and electron impact ionization of hydrogen may play roles as particle sources in this extremely low-energy beam after the compensation of beam ion space charge.

  7. Sequence dependent free energy profiles of localized B- to A-form transition of DNA in water

    NASA Astrophysics Data System (ADS)

    Kulkarni, Mandar; Mukherjee, Arnab

    2013-10-01

    DNA carries an inherent polymorphism, which surfaces under various external conditions. While B-form remains predominant under normal physiological conditions for most of the DNA sequences, low humidity and increased ion concentration cause B- to A-form transition. Certain proteins and molecules also sometimes cause local deformation of the DNA to the specific A-form. Previous experimental and computational studies focused on the overall B- to A-form transition. Here for the first time we investigated thermodynamics and mechanism of B- to A-form transition in water for various DNA sequences at a local dinucleotide base pair level. We introduced a new reaction coordinate Zp', based on the unique order parameter Zp, to drive B- to A-form transition locally and thereby calculate free energy profiles for the same for all the ten different dinucleotide steps embedded in a twelve base pair DNA. Results show that the trend of "A" and "B" philicity observed in experiment is preserved even at this local dinucleotide level, indicating its localized origin. Higher free energy cost obtained here is attributed to the cost of creating B/A junctions along with formation of B->A transition at dimer level. We find that while water energetically stabilizes A-form for all the ten different dinucleotide steps to various extents, entropy acts against it. Therefore, we find that the stability of B-form DNA in water is entropic in origin. Mechanism of the conversion appears to be triggered by Slide; however, backbone parameters change concertedly.

  8. Automating the Transition Between Sensorless Motor Control Methods for the NASA Glenn Research Center Flywheel Energy Storage System

    NASA Technical Reports Server (NTRS)

    Fehrmann, Elizabeth A.; Kenny, Barbara H.

    2004-01-01

    The NASA Glenn Research Center (GRC) has been working to advance the technology necessary for a flywheel energy storage system for the past several years. Flywheels offer high efficiency, durability, and near-complete discharge capabilities not produced by typical chemical batteries. These characteristics show flywheels to be an attractive alternative to the more typical energy storage solutions. Flywheels also offer the possibility of combining what are now two separate systems in space applications into one: energy storage, which is currently provided by batteries, and attitude control, which is currently provided by control moment gyroscopes (CMGs) or reaction wheels. To date, NASA Glenn research effort has produced the control algorithms necessary to demonstrate flywheel operation up to a rated speed of 60,000 RPM and the combined operation of two flywheel machines to simultaneously provide energy storage and single axis attitude control. Two position-sensorless algorithms are used to control the motor/generator, one for low (0 to 1200 RPM) speeds and one for high speeds. The algorithm allows the transition from the low speed method to the high speed method, but the transition from the high to low speed method was not originally included. This leads to a limitation in the existing motor/generator control code that does not allow the flywheels to be commanded to zero speed (and back in the negative speed direction) after the initial startup. In a multi-flywheel system providing both energy storage and attitude control to a spacecraft, speed reversal may be necessary.

  9. Ab initio modeling of the two-dimensional energy landscape of screw dislocations in bcc transition metals

    NASA Astrophysics Data System (ADS)

    Dezerald, L.; Ventelon, Lisa; Clouet, E.; Denoual, C.; Rodney, D.; Willaime, F.

    2014-01-01

    A density functional theory (DFT) study of the 1/2<111> screw dislocation was performed in the following body-centered cubic transition metals: V, Nb, Ta, Cr, Mo, W, and Fe. The energies of the easy, hard, and split core configurations, as well as the pathways between them, were investigated and used to generate the two-dimensional (2D) Peierls potential, i.e. the energy landscape seen by the dislocation as a function of its position in the (111) plane. In all investigated elements, the nondegenerate easy core is the minimum energy configuration, while the split core configuration, centered in the immediate vicinity of a <111> atomic column, has a high energy near or above that of the hard core. This unexpected result yields 2D Peierls potentials very different from the usually assumed landscapes. The 2D Peierls potential in Fe differs from the other transition metals, with a monkey saddle instead of a local maximum located at the hard core. An estimation of the Peierls stress from the shape of the Peierls barrier is presented in all investigated metals. A strong group dependence of the core energy is also evidenced, related to the position of the Fermi level with respect to the minimum of the pseudogap of the electronic density of states.

  10. Making Energy-Efficiency and Productivity Investments in Commercial Buildings: Choice of Investment Models

    SciTech Connect

    Jones, D.W.

    2002-05-16

    This study examines the decision to invest in buildings and the types of investment decision rules that may be employed to inform the ''go--no go'' decision. There is a range of decision making tools available to help in investment choices, which range from simple rules of thumb such as payback periods, to life-cycle analysis, to decision theoretic approaches. Payback period analysis tends to point toward lower first costs, whereas life-cycle analysis tends to minimize uncertainties over future events that can affect profitability. We conclude that investment models that integrate uncertainty offer better explanations for the behavior that is observed, i.e., people tend to delay investments in technologies that life-cycle analysis finds cost-effective, and these models also lead to an alternative set of policies targeted at reducing of managing uncertainty.

  11. Effective Hamiltonians for correlated narrow energy band systems and magnetic insulators: Role of spin-orbit interactions in metal-insulator transitions and magnetic phase transitions.

    PubMed

    Chakraborty, Subrata; Vijay, Amrendra

    2016-04-14

    Using a second-quantized many-electron Hamiltonian, we obtain (a) an effective Hamiltonian suitable for materials whose electronic properties are governed by a set of strongly correlated bands in a narrow energy range and (b) an effective spin-only Hamiltonian for magnetic materials. The present Hamiltonians faithfully include phonon and spin-related interactions as well as the external fields to study the electromagnetic response properties of complex materials and they, in appropriate limits, reduce to the model Hamiltonians due to Hubbard and Heisenberg. With the Hamiltonian for narrow-band strongly correlated materials, we show that the spin-orbit interaction provides a mechanism for metal-insulator transition, which is distinct from the Mott-Hubbard (driven by the electron correlation) and the Anderson mechanism (driven by the disorder). Next, with the spin-only Hamiltonian, we demonstrate the spin-orbit interaction to be a reason for the existence of antiferromagnetic phase in materials which are characterized by a positive isotropic spin-exchange energy. This is distinct from the Néel-VanVleck-Anderson paradigm which posits a negative spin-exchange for the existence of antiferromagnetism. We also find that the Néel temperature increases as the absolute value of the spin-orbit coupling increases. PMID:27083708

  12. Students' meaning making in science: solving energy resource problems in virtual worlds combined with spreadsheets to develop graphs

    NASA Astrophysics Data System (ADS)

    Krange, Ingeborg; Arnseth, Hans Christian

    2012-09-01

    The aim of this study is to scrutinize the characteristics of conceptual meaning making when students engage with virtual worlds in combination with a spreadsheet with the aim to develop graphs. We study how these tools and the representations they contain or enable students to construct serve to influence their understanding of energy resource consumption. The data were gathered in 1st grade upper-secondary science classes and they constitute the basis for the interaction analysis of students' meaning making with representations. Our analyses demonstrate the difficulties involved in developing students' orientation toward more conceptual orientations to representations of the knowledge domain. Virtual worlds do not in themselves represent a solution to this problem.

  13. Confining interparticle potential makes both heat transport and energy diffusion anomalous in one-dimensional phononic systems

    NASA Astrophysics Data System (ADS)

    Kosevich, Yuriy A.; Savin, Alexander V.

    2016-10-01

    We provide molecular dynamics simulation of heat transport and energy diffusion in one-dimensional molecular chains with different interparticle pair potentials at zero and non-zero temperature. We model the thermal conductivity (TC) and energy diffusion (ED) in the chain of coupled rotators and in the Lennard-Jones chain either without or with the confining parabolic interparticle potential. The considered chains without the confining potential have normal TC and ED at non-zero temperature, while the corresponding chains with the confining potential are characterized by anomalous (diverging with the system length) TC and superdiffusion of energy. Similar effect is produced by the anharmonic quartic confining pair potential. We confirm in such a way that, surprisingly, the confining pair potential makes both heat transport and energy diffusion anomalous in one-dimensional phononic systems. We show that the normal TC is always accompanied by the normal ED in the thermalized anharmonic chains, while the superdiffusion of energy occurs in the thermalized chains with only anomalous heat transport.

  14. Lightweight, low cost radiant energy collector and method for making same

    SciTech Connect

    Sorko-Ram, P.

    1984-09-04

    A dish-shaped, radiant energy collector comprises a thin, concave, thermoplastic cover having a reflective layer of metallization vapor deposited on the convex side thereof. A coating of foamed resin is applied to the metallization in order to render the collector self-supporting. Struts or a layer of honeycomb cardboard and/or fiberglass may be introduced into the sandwiched composite to provide further structural rigidity. The cover is produced by forming a flat sheet of acrylic plastic which is transparent to the wavelengths of interest.

  15. Layered reactive particles with controlled geometries, energies, and reactivities, and methods for making the same

    DOEpatents

    Fritz, Gregory M; Knepper, Robert Allen; Weihs, Timothy P; Gash, Alexander E; Sze, John S

    2013-04-30

    An energetic composite having a plurality of reactive particles each having a reactive multilayer construction formed by successively depositing reactive layers on a rod-shaped substrate having a longitudinal axis, dividing the reactive-layer-deposited rod-shaped substrate into a plurality of substantially uniform longitudinal segments, and removing the rod-shaped substrate from the longitudinal segments, so that the reactive particles have a controlled, substantially uniform, cylindrically curved or otherwise rod-contoured geometry which facilitates handling and improves its packing fraction, while the reactant multilayer construction controls the stability, reactivity and energy density of the energetic composite.

  16. Layered reactive particles with controlled geometries, energies, and reactivities, and methods for making the same

    DOEpatents

    Fritz, Gregory M.; Weihs, Timothy P.; Grzyb, Justin A.

    2016-07-05

    An energetic composite having a plurality of reactive particles each having a reactive multilayer construction formed by successively depositing reactive layers on a rod-shaped substrate having a longitudinal axis, dividing the reactive-layer-deposited rod-shaped substrate into a plurality of substantially uniform longitudinal segments, and removing the rod-shaped substrate from the longitudinal segments, so that the reactive particles have a controlled, substantially uniform, cylindrically curved or otherwise rod-contoured geometry which facilitates handling and improves its packing fraction, while the reactant multilayer construction controls the stability, reactivity and energy density of the energetic composite.

  17. High energy product permanent magnet having improved intrinsic coercivity and method of making same

    DOEpatents

    Ramesh, Ramamoorthy; Thomas, Gareth

    1990-01-01

    A high energy rare earth-ferromagnetic metal permanent magnet is disclosed which is characterized by improved intrinsic coercivity and is made by forming a particulate mixture of a permanent magnet alloy comprising one or more rare earth elements and one or more ferromagnetic metals and forming a second particulate mixture of a sintering alloy consisting essentially of 92-98 wt. % of one or more rare earth elements selected from the class consisting of Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and mixtures of two or more of such rare earth elements, and 2-8 wt. % of one or more alloying metals selected from the class consisting of Al, Nb, Zr, V, Ta, Mo, and mixtures of two or more of such metals. The permanent magnet alloy particles and sintering aid alloy are mixed together and magnetically oriented by immersing the mixture in an axially aligned magnetic field while cold pressing the mixture. The compressed mixture is then sintered at a temperature above the melting point of the sintering aid and below the melting point of the permanent magnet alloy to thereby coat the particle surfaces of the permanent magnetic alloy particles with the sintering aid while inhibiting migration of the rare earth element in the sintering aid into the permanent magnet alloy particles to thereby raise the intrinsic coercivity of the permanent magnet alloy without substantially lowering the high energy of the permanent magnet alloy.

  18. NASA Earth Observations Informing Renewable Energy Management and Policy Decision Making

    NASA Technical Reports Server (NTRS)

    Eckman, Richard S.; Stackhouse, Paul W., Jr.

    2008-01-01

    The NASA Applied Sciences Program partners with domestic and international governmental organizations, universities, and private entities to improve their decisions and assessments. These improvements are enabled by using the knowledge generated from research resulting from spacecraft observations and model predictions conducted by NASA and providing these as inputs to the decision support and scenario assessment tools used by partner organizations. The Program is divided into eight societal benefit areas, aligned in general with the Global Earth Observation System of Systems (GEOSS) themes. The Climate Application of the Applied Sciences Program has as one of its focuses, efforts to provide for improved decisions and assessments in the areas of renewable energy technologies, energy efficiency, and climate change impacts. The goals of the Applied Sciences Program are aligned with national initiatives such as the U.S. Climate Change Science and Technology Programs and with those of international organizations including the Group on Earth Observations (GEO) and the Committee on Earth Observation Satellites (CEOS). Activities within the Program are funded principally through proposals submitted in response to annual solicitations and reviewed by peers.

  19. NREL's Water Power Software Makes a Splash; NREL Highlights, Research & Development, NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    WEC-Sim is a DOE-funded software tool being jointly developed by NREL and SNL. WEC-Sim computationally models wave energy converters (WEC), devices that generate electricity using movement of water systems such as oceans, rivers, etc. There is great potential for WECs to generate electricity, but as of yet, the industry has yet to establish a commercially viable concept. Modeling, design, and simulations tools are essential to the successful development of WECs. Commercial WEC modeling software tools can't be modified by the user. In contrast, WEC-Sim is a free, open-source, and flexible enough to be modified to meet the rapidly evolving needs of the WEC industry. By modeling the power generation performance and dynamic loads of WEC designs, WEC-Sim can help support the development of new WEC devices by optimizing designs for cost of energy and competitiveness. By being easily accessible, WEC-Sim promises to help level the playing field in the WEC industry. Importantly, WEC-Sim is also excellent at its job! In 2014, WEC-Sim was used in conjunction with NREL’s FAST modeling software to win a hydrodynamic modeling competition. WEC-Sim and FAST performed very well at predicting the motion of a test device in comparison to other modeling tools. The most recent version of WEC-Sim (v1.1) was released in April 2015.

  20. Blue and red shifts of interband transition energy in supported Au nanoclusters on SiO2 and HOPG investigated by reflection electron energy-loss spectroscopy.

    PubMed

    Borisyuk, P V; Troyan, V I; Pushkin, M A; Borman, V D; Tronin, V N

    2012-11-01

    Gold nanoclusters supported on SiO2 and HOPG are experimentally investigated by the reflection electron energy-loss spectroscopy. Two different trends in the size-dependence of the position of the energy-loss peak corresponding to the interband Au 5d --> 6s6p transition is observed: a blue shift for Au clusters on SiO2 and a red shift for Au clusters on HOPG. The different behaviors are qualitatively explained by the influence of the substrate on the spectrum of electronic states in Au nanoclusters.

  1. Body Dissatisfaction, Living Away from Parents, and Poor Social Adjustment Predict Binge Eating Symptoms in Young Women Making the Transition to University

    ERIC Educational Resources Information Center

    Barker, Erin T.; Galambos, Nancy L.

    2007-01-01

    The current study explored how body dissatisfaction and challenges associated with the transition to university predicted symptoms of binge eating. Participants were 101 female full-time first-year university students (M=18.3 years of age; SD=0.50) who completed a background questionnaire and a web-based daily checklist assessing binge eating.…

  2. Graduate Dress Code How Undergraduates Are Planning to Use Hair, Clothes and Make-Up to Smooth Their Transition to the Workplace

    ERIC Educational Resources Information Center

    Cutts, Beth; Hooley, Tristram; Yates, Julia

    2015-01-01

    This article explores the relationship between students' identities, their ideas about professional appearance and their anticipated transition to the world of work. It is based on a series of semi-structured interviews with 13 students from a vocationally-focused university in England. It was found that participants viewed clothing and appearance…

  3. What Makes a Difference? Influences on Postschool Outcomes of Youth with Disabilities. The Third Comprehensive Report from the National Longitudinal Transition Study of Special Education Students.

    ERIC Educational Resources Information Center

    Wagner, Mary; And Others

    This report uses data from the National Longitudinal Transition Study (NLTS) of Special Education Students to identify specific influences on postschool outcomes of youth with disabilities. The first chapter describes the NLTS, summarizes key postschool outcomes for young people with disabilities, and presents a framework suggesting influential…

  4. Using Hydrated Salt Phase Change Materials for Residential Air Conditioning Peak Demand Reduction and Energy Conservation in Coastal and Transitional Climates in the State of California

    NASA Astrophysics Data System (ADS)

    Lee, Kyoung Ok

    The recent rapid economic and population growth in the State of California have led to a significant increase in air conditioning use, especially in areas of the State with coastal and transitional climates. This fact makes that the electric peak demand be dominated by air conditioning use of residential buildings in the summer time. This extra peak demand caused by the use of air conditioning equipment lasts only a few days out of the year. As a result, unavoidable power outages have occurred when electric supply could not keep up with such electric demand. This thesis proposed a possible solution to this problem by using building thermal mass via phase change materials to reduce peak air conditioning demand loads. This proposed solution was tested via a new wall called Phase Change Frame Wall (PCFW). The PCFW is a typical residential frame wall in which Phase Change Materials (PCMs) were integrated to add thermal mass. The thermal performance of the PCFWs was first evaluated, experimentally, in two test houses, built for this purpose, located in Lawrence, KS and then via computer simulations of residential buildings located in coastal and transitional climates in California. In this thesis, a hydrated salt PCM was used, which was added in concentrations of 10% and 20% by weight of the interior sheathing of the walls. Based on the experimental results, under Lawrence, KS weather, the PCFWs at 10% and 20% of PCM concentrations reduced the peak heat transfer rates by 27.0% and 27.3%, on average, of all four walls, respectively. Simulated results using California climate data indicated that PCFWs would reduce peak heat transfer rates by 8% and 19% at 10% PCM concentration and 12.2% and 27% at 20% PCM concentration for the coastal and transitional climates, respectively. Furthermore, the PCFWs, at 10% PCM concentration, would reduce the space cooling load and the annual energy consumption by 10.4% and 7.2%, on average in both climates, respectively.

  5. Cross-calibration of the transition radiation detector of AMS-02 for an energy measurement of cosmic-ray ions

    NASA Astrophysics Data System (ADS)

    Obermeier, A.; Korsmeier, M.

    2015-01-01

    Since May 2011 the AMS-02 experiment is installed on the International Space Station and is observing cosmic radiation. It consists of several state-of-the-art sub-detectors, which redundantly measure charge and energy of traversing particles. Due to the long exposure time of AMS-02 of many years the measurement of momentum for protons and ions is limited systematically by the spatial resolution and magnetic field strength of the silicon tracker. The maximum detectable rigidity for protons is about 1.8 TV, for helium about 3.6 TV. We investigate the possibility to extend the range of the energy measurement for heavy nuclei (Z ⩾ 2) with the transition radiation detector (TRD). The response function of the TRD shows a steep increase in signal from the level of ionization at a Lorentz factor γ of about 500 to γ ≈ 20, 000 , where the transition radiation signal saturates. For heavy ions the signal fluctuations in the TRD are sufficiently small to allow an energy measurement with the TRD beyond the limitations of the tracker. The energy resolution of the TRD is determined and reaches a level of about 20% for boron (Z = 5). After adjusting the operational parameters of the TRD a measurement of boron and carbon could be possible up to 5 TeV/nucleon.

  6. Relativistic CI+all-order calculations of U III energies, g-factors, transition rates and lifetimes

    NASA Astrophysics Data System (ADS)

    Savukov, Igor; Safronova, Ulyana; Safronova, Marianna

    2016-05-01

    Excitation energies, term designations, g-factors, transition rates and lifetimes of U2+ are determined using a relativistic configuration interaction (CI) + all-order (linearized coupled-cluster, LCC) approach. The all-order energies are compared with CI+many-body-perturbation-theory (MBPT) and available experimental energies. Close agreement has been found with experiment, within hundreds of cm-1. In addition, lifetimes of higher levels have been calculated for comparison with three experimentally measured lifetimes, and close agreement was found within t he experimental error. CI-LCC calculations constitute a benchmark test of the CI+all-order method in complex relativistic systems such as actinides and their ions with many valence electrons. The theory yields many energy levels, g-factors, transition rates, and lifetimes of U2+ that are not available from experiment. The theory can be applied to other multi-valence atoms and ions, which would be of interest to many applications. The work of I. Savukov has been performed under the auspices of the U.S. DOE by LANL under Contract No. DE-AC52-06NA25396.M.S.S. acknowledges support from the Gordon Godfrey Fellowship program, UNSW and U.S. NSF Grant No. PHY-1404156.

  7. Making solar laws work: a study of state solar energy incentives

    SciTech Connect

    Roessner, J.D.

    1980-11-01

    The results of a research investigation of solar financial and research, demonstration, and development (RD and D) incentive programs in 18 states are summarized. The investigation focuses upon implementation - the organization and administrative processes required to convert a law into a viable program. Eleven financial and 12 RD and D programs were investigated. Results indicate that four conditions are common to successful implementation of both types of incentive programs: the opportunity to use solar energy as a heating source; characteristics of the agency selected to complement the law; involvement of outside groups in program implementation; and the specificity of guidance given to those responsible for implementation. Other conditions specific to the implementation of each type of program are discussed as well as the implications of these findings for state and federal policy makers.

  8. Lessons from an Energy Curriculum for the Senior High Grades. Unit I - Energy Decision Making (Housing and Home Furnishings). Energy Education Curriculum Project.

    ERIC Educational Resources Information Center

    Indiana State Dept. of Public Instruction, Indianapolis. Div. of Curriculum.

    Energy education units (consisting of a general teacher's guide and nine units containing a wide variety of energy lessons, resources, learning aids, and bibliography) were developed for the Indiana Energy Education Program from existing energy education materials. The units were designed to serve as an entire curriculum, resource document,…

  9. Histomorphological features of resected bladder tumors: Do energy source makes any difference

    PubMed Central

    Saini, Ashish Kumar; Ahuja, Arvind; Seth, Amlesh; Dogra, Prem Nath; Kumar, Rajeev; Singh, Prabhjot; Gupta, Siddhartha Dutta

    2015-01-01

    Context: The recent advent of bipolar energy in bladder tumor resection has raised many questions regarding density of current and its effect on histopathology of the resected transurethral resection of bladder tumor (TURBT) chips. Aims: The aim of this study is to evaluate the histomorphological features in resected bladder tumors comparing bipolar versus conventional (monopolar) energy. Settings and Design: Inclusion criteria were patients with primary presentation of carcinoma urinary bladder undergoing TURBT. The patients with prior resections were excluded as these could jeopardize the results of cautery artifacts. Materials and Methods: From February 2010 to December 2011, 61 patients with primary carcinoma bladder and meeting our inclusion criteria were compared. Group 1 (n = 31) underwent bipolar-TURBT (B-TURBT) and Group 2 (n = 30) monopolar-TURBT (M-TURBT). Two pathologists, who were blinded to the form of electrocautery used, examined the resected tissue. The degree of cautery artifact in each specimen was recorded. The severity of the cautery artifact was graded as absent, mild, moderate, or severe. The mean age, tumor size, and resection time were recorded in both groups. Statistical Analysis Used: Data were analyzed using SPSS 16. Data were compared in between groups using paired t-test and Pearson's Chi-square test. The significance level was set at 0.05. Results: The mean age, tumor size, and resection time were similar in between the two groups. The pathologists had no obscurity in reaching a correct diagnosis in all cases. The cautery artifacts were graded as absent in 10 (32.2%) and 8 (26.67%), mild in 12 (38.7%) and 11 (36.67%), moderate in 5 (16.1%) and 7 (23.33%) and severe in 4 (12.9%) and 5 (16.66%) cases, respectively in Group 1 and 2. There was no statistically significant histomorphogical dissimilarity between specimens according to the type of cautery used. Conclusions: Bladder tissue obtained from B-TURBT is of equivalent

  10. Free-Free Transitions in the Presence of Laser Fields and Debye Potential at Very Low Incident Electron Energies

    NASA Technical Reports Server (NTRS)

    Bhatia, Anand

    2012-01-01

    We study the free-free transition in electron-helium ion in the ground state and embedded in a Debye potential in the presence of an external laser field at very low incident electron energies. The laser field is treated classically while the collision dynamics is treated quantum mechanically. The laser field is chosen as monochromatic, linearly polarized and homogeneous. The incident electron is considered to be dressed by the laser field in a nonperturbative manner by choosing Volkov wave function for it. The scattering wave function for the incident electron on the target embedded in a Debye potential is solved numerically by taking into account the effect of electron exchange. We calculate the laser-assisted differential and total cross sections for free-free transition for absorption/emission of a single photon or no photon exchange. The results will be presented at the conference.

  11. Free-free transitions in the presence of laser fields and Debye potential at very low incident electron energies

    NASA Astrophysics Data System (ADS)

    Bhatia, Anand

    2012-06-01

    We study the free-free transition in electron-helium ion in the ground state and embedded in a Debye potential in the presence of an external laser field at very low incident electron energies. The laser field is treated classically while the collision dynamics is treated quantum mechanically. The laser field is chosen as monochromatic, linearly polarized and homogeneous. The incident electron is considered to be dressed by the laser field in a nonperturbative manner by choosing Volkov wave function for it. The scattering wave function for the incident electron on the target embedded in a Debye potential is solved numerically by taking into account the effect of electron exchange. We calculate the laser-assisted differential and total cross sections for free-free transition for absorption/emission of a single photon or no photon exchange. The results will be presented at the conference.

  12. Free-free transitions in the presence of laser fields and Debye potential at very low incident electron energies

    NASA Astrophysics Data System (ADS)

    Bhatia, Anand

    2013-05-01

    We study the free-free transition in e-He+ system in the ground state and embedded in a Debye potential in the presence of an external laser field which is monochromatic, linearly polarized and homogeneous, at very low incident electron energies. The laser field is treated classically while the collision dynamics is treated quantum mechanically. The incident electron is considered to be dressed by the laser field in a nonperturbative manner by choosing Volkov wave function. The scattering function for the incident electron on the target is solved numerically by taking into account the effect of electron exchange. We calculate the laser-assisted differential and total cross sections for free-free transitions for absorption/emission of a single photon or no photon exchange. The cross sections for e-He+ system are much larger than e-H system. The results will be presented at the conference.

  13. Improved energy of the 21.5 keV M1 + E2 nuclear transition in 151Eu

    NASA Astrophysics Data System (ADS)

    Inoyatov, A. Kh.; Kovalík, A.; Filosofov, D. V.; Ryšavý, M.; Perevoshchikov, L. L.; Baimukhanova, A.

    2016-05-01

    Using internal conversion electron spectroscopy, improved energy 21 541.5±0.5 eV was determined for the 21.5keV M1 + E2 nuclear transition in 151Eu populated in the electron capture decay of 151Gd . This value was found to agree well with the present adopted value but is much more accurate. A value of 0.0305±0.0011 derived for the E2 admixture parameter \\vertδ(E2/M1)\\vert from the measured conversion electron line intensities corresponds to the present adopted value. A possible effect of nuclear structure on the multipolarity of the 21.5 keV transition was also investigated.

  14. Mutation in the SH1 helix reduces the activation energy of the ATP-induced conformational transition of myosin.

    PubMed

    Iwai, Sosuke; Chaen, Shigeru

    2007-05-25

    The SH1 helix is a joint that links the converter subdomain to the rest of the myosin motor domain. Recently, we showed that a mutation within the SH1 helix in Dictyostelium myosin II (R689H) reduced the elasticity and thermal stability of the protein. To reveal the involvement of the SH1 helix in ATP-dependent conformational changes of the motor domain, we have investigated the effects of the R689H mutation on the conformational changes of the converter, using a GFP-based fluorescence resonance energy transfer method. Although the mutation does not seem to strongly affect conformations, we found that it significantly reduced the activation energy required for the ATP-induced conformational transition corresponding to the recovery stroke. Given the effects of the mutation on the mechanical properties of myosin, we propose that the SH1 helix plays an important role in the mechanochemical energy conversion underlying the conformational change of the myosin motor domain.

  15. The energy input mechanism into the lower transition regions between stellar chromospheres and coronae

    NASA Technical Reports Server (NTRS)

    Boehm-Vitense, Erika

    1988-01-01

    The ratio of the emission line fluxes for the C II and C IV lines in the lower transition regions (T = 30,000 to 100,000 K) between stellar chromospheres and transition layers is shown to depend mainly on the temperature gradient in the line emitting regions which can therefore be determined from this line ratio. From the observed constant (within the limits of observational error) ratio of the emission line fluxes of the C II (1335 A) and C IV (1550 A) lines it is concluded that the temperature gradients in the lower transition layers are similar for the large majority of stars independently of T sub eff, L, and degree of activity. This means that the temperature dependence of the damping length for the mechanical flux must be the same for all these stars. Since for different kinds of mechanical fluxes the dependence of the damping length on gas pressure and temperature is quite different, it is concluded that the same heating mechanism must be responsible for the heating of all the lower transition layers of these stars, regardless of their chromospheric activity. Only the amount of mechanical flux changes. The T Tauri stars are exceptions: their emission lines are probably mainly due to circumstellar material.

  16. Activation Energy of the Low-pH-Induced Lamellar to Bicontinuous Cubic Phase Transition in Dioleoylphosphatidylserine/Monoolein.

    PubMed

    Oka, Toshihiko; Saiki, Takahiro; Alam, Jahangir Md; Yamazaki, Masahito

    2016-02-01

    Electrostatic interaction is an important factor for phase transitions between lamellar liquid-crystalline (Lα) and inverse bicontinuous cubic (QII) phases. We investigated the effect of temperature on the low-pH-induced Lα to double-diamond cubic (QII(D)) phase transition in dioleoylphosphatidylserine (DOPS)/monoolein (MO) using time-resolved small-angle X-ray scattering with a stopped-flow apparatus. Under all conditions of temperature and pH, the Lα phase was directly transformed into an intermediate inverse hexagonal (HII) phase, and subsequently the HII phase slowly converted to the QII(D) phase. We obtained the rate constants of the initial step (i.e., the Lα to HII phase transition) and of the second step (i.e., the HII to QII(D) phase transition) using the non-negative matrix factorization method. The rate constant of the initial step increased with temperature. By analyzing this result, we obtained the values of its apparent activation energy, Ea (Lα → HII), which did not change with temperature but increased with an increase in pH. In contrast, the rate constant of the second step decreased with temperature at pH 2.6, although it increased with temperature at pH 2.7 and 2.8. These results indicate that the value of Ea (HII → QII(D)) at pH 2.6 increased with temperature, but the values of Ea (HII → QII(D)) at pH 2.7 and 2.8 were constant with temperature. The values of Ea (HII → QII(D)) were smaller than those of Ea (Lα → HII) at the same pH. We analyzed these results using a modified quantitative theory on the activation energy of phase transitions of lipid membranes proposed initially by Squires et al. (Squires, A. M.; Conn, C. E.; Seddon, J. M.; Templer, R. H. Soft Matter 2009, 5, 4773). On the basis of these results, we discuss the mechanism of this phase transition.

  17. Activation Energy of the Low-pH-Induced Lamellar to Bicontinuous Cubic Phase Transition in Dioleoylphosphatidylserine/Monoolein.

    PubMed

    Oka, Toshihiko; Saiki, Takahiro; Alam, Jahangir Md; Yamazaki, Masahito

    2016-02-01

    Electrostatic interaction is an important factor for phase transitions between lamellar liquid-crystalline (Lα) and inverse bicontinuous cubic (QII) phases. We investigated the effect of temperature on the low-pH-induced Lα to double-diamond cubic (QII(D)) phase transition in dioleoylphosphatidylserine (DOPS)/monoolein (MO) using time-resolved small-angle X-ray scattering with a stopped-flow apparatus. Under all conditions of temperature and pH, the Lα phase was directly transformed into an intermediate inverse hexagonal (HII) phase, and subsequently the HII phase slowly converted to the QII(D) phase. We obtained the rate constants of the initial step (i.e., the Lα to HII phase transition) and of the second step (i.e., the HII to QII(D) phase transition) using the non-negative matrix factorization method. The rate constant of the initial step increased with temperature. By analyzing this result, we obtained the values of its apparent activation energy, Ea (Lα → HII), which did not change with temperature but increased with an increase in pH. In contrast, the rate constant of the second step decreased with temperature at pH 2.6, although it increased with temperature at pH 2.7 and 2.8. These results indicate that the value of Ea (HII → QII(D)) at pH 2.6 increased with temperature, but the values of Ea (HII → QII(D)) at pH 2.7 and 2.8 were constant with temperature. The values of Ea (HII → QII(D)) were smaller than those of Ea (Lα → HII) at the same pH. We analyzed these results using a modified quantitative theory on the activation energy of phase transitions of lipid membranes proposed initially by Squires et al. (Squires, A. M.; Conn, C. E.; Seddon, J. M.; Templer, R. H. Soft Matter 2009, 5, 4773). On the basis of these results, we discuss the mechanism of this phase transition. PMID:26766583

  18. Making industrial energy efficiency mainstream and profitable: Where public benefit and private interests intersect

    SciTech Connect

    McKane, Aimee T.; Tutterow, Vestal; Cockrill, Chris

    2001-05-31

    In 1996, the US Department of Energy s Office of Industrial Technologies (OIT) Motor Challenge program began a unique collaboration with industry called the Allied Partner program. Partnerships were sought with equipment suppliers and manufacturers, utilities, consultants, and state agencies that had extensive existing relationships with industrial customers. Partners were neither paid nor charged a fee for participation. The assumption was that these relationships could serve as the foundation for conveying a motor system efficiency message to many more industrial facilities than could be reached through a typical government-to-end-user program model. A substantial effort was made to engage industrial suppliers in delivering program information as part of their customer interactions. A recent independent evaluation of the Motor Challenge program attributes $16.9 million or nearly 67 percent of the total annual program energy savings to the efforts of Allied Partners in the first three years of operation.In 1997, the Compressed Air Challenge(R) (CAC) was developed as an outgrowth of the partnership concept. In this model, OIT is one of 15 sponsors who collaborated to create a national program of compressed air system training. The CAC has gone a step further by setting up a development and deployment model based on shared interests and shared costs among public, private, and not-for-profit organizations that serve industrial customers. Since the first CAC training session in 1999, approximately 3800 people have been trained by CAC qualified instructors--both end users and suppliers. More impressively, the entire compressed air market has begun to shift from a component-based to a system-based approach, largely as the result of collaboration. The typical leverage for OIT participation in a CAC training session is 10:1. During the past year, OIT has reorganized to integrate all of its near-term industrial offerings such as the Motor, Compressed Air, and Steam

  19. Origin of the High-speed Jets Fom Magnetic Flux Emergence in the Solar Transition Region as well as Their Mass and Energy Contribuctions to the Solar Wind

    NASA Astrophysics Data System (ADS)

    Liping, Y.; He, J.; Peter, H.; Tu, C. Y.; Feng, X. S.

    2015-12-01

    In the solar atmosphere, the jets are ubiquitous and found to be at various spatia-temporal scales. They are significant to understand energy and mass transport in the solar atmosphere. Recently, the high-speed transition region jets are reported from the observation. Here we conduct a numerical simulation to investigate the mechanism in their formation, as well as their mass and energy contributions to the solar wind. Driven by the supergranular convection motion, the magnetic reconnection between the magnetic loop and the background open flux occurring in the transition region is simulated with a two-dimensional MHD model. The simulation results show that not only a fast hot jet, much resemble the found transition region jets, but also a adjacent slow cool jet, mostly like classical spicules, is launched. The force analysis shows that the fast hot jet is continually driven by the Lorentz force around the reconnection region, while the slow cool jet is induced by an initial kick through the Lorentz force associated with the emerging magnetic flux. Also, the features of the driven jets change with the amount of the emerging magnetic flux, giving the varieties of both jets.With the developed one-dimensional hydrodynamic solar wind model, the time-dependent pulses are imposed at the bottom to simulate the jet behaviors. The simulation results show that without other energy source, the injected plasmas are accelerated effectively to be a transonic wind with a substantial mass flux. The rapid acceleration occurs close to the Sun, and the resulting asymptotic speeds, number density at 0.3 AU, as well as mass flux normalized to 1 AU are compatible with in site observations. As a result of the high speed, the imposed pulses lead to a train of shocks traveling upward. By tracing the motions of the injected plasma, it is found that these shocks heat and accelerate the injected plasma to make part of them propagate upward and eventually escape. The parametric study shows

  20. Vibrational energy transfer near a dissociative adsorption transition state: State-to-state study of HCl collisions at Au(111).

    PubMed

    Geweke, Jan; Shirhatti, Pranav R; Rahinov, Igor; Bartels, Christof; Wodtke, Alec M

    2016-08-01

    In this work we seek to examine the nature of collisional energy transfer between HCl and Au(111) for nonreactive scattering events that sample geometries near the transition state for dissociative adsorption by varying both the vibrational and translational energy of the incident HCl molecules in the range near the dissociation barrier. Specifically, we report absolute vibrational excitation probabilities for HCl(v = 0 → 1) and HCl(v = 1 → 2) scattering from clean Au(111) as a function of surface temperature and incidence translational energy. The HCl(v = 2 → 3) channel could not be observed-presumably due to the onset of dissociation. The excitation probabilities can be decomposed into adiabatic and nonadiabatic contributions. We find that both contributions strongly increase with incidence vibrational state by a factor of 24 and 9, respectively. This suggests that V-T as well as V-EHP coupling can be enhanced near the transition state for dissociative adsorption at a metal surface. We also show that previously reported HCl(v = 0 → 1) excitation probabilities [Q. Ran et al., Phys. Rev. Lett. 98, 237601 (2007)]-50 times smaller than those reported here-were influenced by erroneous assignment of spectroscopic lines used in the data analysis. PMID:27497574