The Hybrid Automobile and the Atkinson Cycle

ERIC Educational Resources Information Center

Feldman, Bernard J.

2008-01-01

The hybrid automobile is a strikingly new automobile technology with a number of new technological features that dramatically improve energy efficiency. This paper will briefly describe how hybrid automobiles work; what are these new technological features; why the Toyota Prius hybrid internal combustion engine operates on the Atkinson cycle…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Romm, J.J.

Many American companies have found that saving energy and cutting pollution dramatically improves the bottom line. But beyond these gains, businesses that launch energy efficiency programs to save money are often astonished to discover unforeseen benefits: energy efficient lighting, heating, cooling, motors, and industrial processes can increase worker productivity, decrease absenteeism, and improve the quality of work performed. Profits created by the jump in worker productivity can exceed energy savings by a factor of ten. Energy efficiency and pollution prevention represent the next wave in manufacturing, following the quality revolution launched by the Japanese in the 1960s. Unless America leadsmore » the lean and clean revolution, economic health will be undermined as other countries develop clean processes and products and US companies suffer competitively. Also, developing countries will leapfrog their wasteful model and buy products and manufacturing processes from foreign firms already practicing lean and clean.« less

Utility of thermal-based two-source energy balance model for estimating vineyard evapotranspiration at field and regional scales

USDA-ARS?s Scientific Manuscript database

The prolonged drought in much of California over the last few years, particularly in the Central Valley region, has caused severe reduction in water reservoir levels and a major depletion of ground water by agriculture. Dramatic improvements in water and irrigation management practices are critical ...

Limiting technologies for particle beams and high energy physics

NASA Astrophysics Data System (ADS)

Panofsky, W. K. H.

1985-07-01

Since 1930 the energy of accelerators had grown by an order of magnitude roughly every 7 years. Like all exponential growths, be they human population, the size of computers, or anything else, this eventually will have to come to an end. When will this happen to the growth of the energy of particle accelerators and colliders? Fortunately, as the energy of accelerators has grown the cost per unit energy has decreased almost as fast as has the increase in energy. The result is that while the energy has increased so dramatically the cost per new installation has increased only by roughly an order of magnitude since the 1930's (corrected for inflation), while the number of accelerators operating at the frontier of the field has shrunk. As is shown in the by now familiar Livingston chart this dramatic decrease in cost has been achieved largely by a succession of new technologies, in addition to the more moderate gains in efficiency due to improved design, economies of scale, etc. We are therefore facing two questions: (1) Is there good reason scientifically to maintain the exponential growth, and (2) Are there new technologies in sight which promise continued decreases in unit costs. The answer to the first question is definitely yes; the answer to the second question is maybe.

Liquid Catholyte Molecules for Nonaqueous Redox Flow Batteries

DOE PAGES

Huang, Jinhua; Cheng, Lei; Assary, Rajeev S.; ...

2014-11-25

In this study, a series of dimethoxybenzene-based catholyte molecules, which are electrochemically reversible at high potential (4.0 V vs Li/Li +) and in the form of liquid, is developed. The liquid nature offers the molecules the possibility of being a solo or co-solvent for nonaqueous redox flow batteries. This could dramatically improve the energy density.

NREL to Research Revolutionary Battery Storage Approaches in Support of

Science.gov Websites

adoption by dramatically improving driving range and reliability, and by providing low-cost carbon have the potential to meet the demanding safety, cost and performance levels for EVs set by ARPA-E, but materials to develop a new low-cost battery that operates similar to a flow battery, where chemical energy

Using Creative Dramatics to Foster Conceptual Learning in a Science Enrichment Program

ERIC Educational Resources Information Center

Hendrix, Rebecca Compton

2011-01-01

This study made analysis of how the integration of creative drama into a science enrichment program enhanced the learning of elementary school students' understanding of sound physics and solar energy. The study also sought to determine if student attitudes toward science could be improved with the inclusion of creative drama as an extension…

Improvement of radiological penumbra using intermediate energy photons (IEP) for stereotactic radiosurgery.

PubMed

O'Malley, Lauren; Pignol, Jean-Philippe; Beachey, David J; Keller, Brian M; Presutti, Joseph; Sharpe, Michael

2006-05-21

Using efficient immobilization and dedicated beam collimation devices, stereotactic radiosurgery ensures highly conformal treatment of small tumours with limited microscopic extension. One contribution to normal tissue irradiation remains the radiological penumbra. This work aims at demonstrating that intermediate energy photons (IEP), above orthovoltage but below megavoltage, improve dose distribution for stereotactic radiosurgery for small irradiation field sizes due to a dramatic reduction of radiological penumbra. Two different simulation systems were used: (i) Monte Carlo simulation to investigate the dose distribution of monoenergetic IEP between 100 keV and 1 MeV in water phantom; (ii) the Pinnacle3 TPS including a virtual IEP unit to investigate the dosimetry benefit of treating with 11 non-coplanar beams a 2 cm tumour in the middle of a brain adjacent to a 1 mm critical structure. Radiological penumbrae below 300 microm are generated for field size below 2 x 2 cm2 using monoenergetic IEP beams between 200 and 400 keV. An 800 kV beam generated in a 0.5 mm tungsten target maximizes the photon intensity in this range. Pinnacle3 confirms the dramatic reduction in penumbra size. DVHs show for a constant dose distribution conformality, improved dose distribution homogeneity and better sparing of critical structures using a 800 kV beam compared to a 6 MV beam.

Improvement of radiological penumbra using intermediate energy photons (IEP) for stereotactic radiosurgery

NASA Astrophysics Data System (ADS)

O'Malley, Lauren; Pignol, Jean-Philippe; Beachey, David J.; Keller, Brian M.; Presutti, Joseph; Sharpe, Michael

2006-05-01

Using efficient immobilization and dedicated beam collimation devices, stereotactic radiosurgery ensures highly conformal treatment of small tumours with limited microscopic extension. One contribution to normal tissue irradiation remains the radiological penumbra. This work aims at demonstrating that intermediate energy photons (IEP), above orthovoltage but below megavoltage, improve dose distribution for stereotactic radiosurgery for small irradiation field sizes due to a dramatic reduction of radiological penumbra. Two different simulation systems were used: (i) Monte Carlo simulation to investigate the dose distribution of monoenergetic IEP between 100 keV and 1 MeV in water phantom; (ii) the Pinnacle3 TPS including a virtual IEP unit to investigate the dosimetry benefit of treating with 11 non-coplanar beams a 2 cm tumour in the middle of a brain adjacent to a 1 mm critical structure. Radiological penumbrae below 300 µm are generated for field size below 2 × 2 cm2 using monoenergetic IEP beams between 200 and 400 keV. An 800 kV beam generated in a 0.5 mm tungsten target maximizes the photon intensity in this range. Pinnacle3 confirms the dramatic reduction in penumbra size. DVHs show for a constant dose distribution conformality, improved dose distribution homogeneity and better sparing of critical structures using a 800 kV beam compared to a 6 MV beam.

Spectromicroscopy and coherent diffraction imaging: focus on energy materials applications.

PubMed

Hitchcock, Adam P; Toney, Michael F

2014-09-01

Current and future capabilities of X-ray spectromicroscopy are discussed based on coherence-limited imaging methods which will benefit from the dramatic increase in brightness expected from a diffraction-limited storage ring (DLSR). The methods discussed include advanced coherent diffraction techniques and nanoprobe-based real-space imaging using Fresnel zone plates or other diffractive optics whose performance is affected by the degree of coherence. The capabilities of current systems, improvements which can be expected, and some of the important scientific themes which will be impacted are described, with focus on energy materials applications. Potential performance improvements of these techniques based on anticipated DLSR performance are estimated. Several examples of energy sciences research problems which are out of reach of current instrumentation, but which might be solved with the enhanced DLSR performance, are discussed.

Living in utility scarcity: energy and water insecurity in Northwest Alaska.

PubMed

Eichelberger, Laura Palen

2010-06-01

This study explored the links between energy and water insecurity in rural Iñupiaq Eskimo villages in Alaska's Northwest Arctic Borough. High energy costs and the need for fuel-based transportation are 2 significant factors in domestic water access for these communities. Dramatic increases in the costs of energy have led to decreased domestic water access, with adverse effects on household hygiene practices. I traced the ways in which the high costs of energy determine water consumption from production to household acquisition and use. Improving sanitation and access to domestic water requires considering the water-energy nexus: the amount and cost of energy required to treat and distribute water as well as manage waste. I use the term utility scarcity to underscore the relationship between domestic water, energy, and health.

Energy Drink Consumption: Beneficial and Adverse Health Effects.

PubMed

Alsunni, Ahmed Abdulrahman

2015-10-01

Consumption of energy drinks has been increasing dramatically in the last two decades, particularly amongst adolescents and young adults. Energy drinks are aggressively marketed with the claim that these products give an energy boost to improve physical and cognitive performance. However, studies supporting these claims are limited. In fact, several adverse health effects have been related to energy drink; this has raised the question of whether these beverages are safe. This review was carried out to identify and discuss the published articles that examined the beneficial and adverse health effects related to energy drink. It is concluded that although energy drink may have beneficial effects on physical performance, these products also have possible detrimental health consequences. Marketing of energy drinks should be limited or forbidden until independent research confirms their safety, particularly among adolescents.

Living in Utility Scarcity: Energy and Water Insecurity in Northwest Alaska

PubMed Central

2010-01-01

This study explored the links between energy and water insecurity in rural Iñupiaq Eskimo villages in Alaska's Northwest Arctic Borough. High energy costs and the need for fuel-based transportation are 2 significant factors in domestic water access for these communities. Dramatic increases in the costs of energy have led to decreased domestic water access, with adverse effects on household hygiene practices. I traced the ways in which the high costs of energy determine water consumption from production to household acquisition and use. Improving sanitation and access to domestic water requires considering the water–energy nexus: the amount and cost of energy required to treat and distribute water as well as manage waste. I use the term utility scarcity to underscore the relationship between domestic water, energy, and health. PMID:20403886

High Performing Ternary Solar Cells through Förster Resonance Energy Transfer between Nonfullerene Acceptors.

PubMed

Yang, Lei; Gu, Wenxing; Hong, Ling; Mi, Yang; Liu, Feng; Liu, Ming; Yang, Yufei; Sharma, Bigyan; Liu, Xinfeng; Huang, Hui

2017-08-16

Nonradiative Förster resonance energy transfer (FRET) is an important mechanism of organic solar cells, which can improve the exciton migration over a long distance, resulting in improvement of efficiency of solar cells. However, the current observations of FRET are very limited, and the efficiencies are less than 9%. In this study, FRET effect was first observed between two nonfullerene acceptors in ternary solar cells, which improved both the absorption range and exciton harvesting, leading to the dramatic enhancement in the short circuit current and power conversion efficiency. Moreover, this strategy is proved to be a versatile platform for conjugated polymers with different bandgaps, resulting in a remarkable efficiency of 10.4%. These results demonstrated a novel method to enhance the efficiency of organic soar cells.

Protecting High Energy Barriers: A New Equation to Regulate Boost Energy in Accelerated Molecular Dynamics Simulations.

PubMed

Sinko, William; de Oliveira, César Augusto F; Pierce, Levi C T; McCammon, J Andrew

2012-01-10

Molecular dynamics (MD) is one of the most common tools in computational chemistry. Recently, our group has employed accelerated molecular dynamics (aMD) to improve the conformational sampling over conventional molecular dynamics techniques. In the original aMD implementation, sampling is greatly improved by raising energy wells below a predefined energy level. Recently, our group presented an alternative aMD implementation where simulations are accelerated by lowering energy barriers of the potential energy surface. When coupled with thermodynamic integration simulations, this implementation showed very promising results. However, when applied to large systems, such as proteins, the simulation tends to be biased to high energy regions of the potential landscape. The reason for this behavior lies in the boost equation used since the highest energy barriers are dramatically more affected than the lower ones. To address this issue, in this work, we present a new boost equation that prevents oversampling of unfavorable high energy conformational states. The new boost potential provides not only better recovery of statistics throughout the simulation but also enhanced sampling of statistically relevant regions in explicit solvent MD simulations.

Preliminary Study of Turbulence for a Lobed Body in Hypersonic Flight

DTIC Science & Technology

2013-02-22

physics. Modest improvements in numerical algorithms, particularly those for solving partial differential equations ( PDEs ), can now be fully...dramatically.[7] In slower speed flow fields, this energy is absorbed mostly in molecular translational and rotational modes, but for hypersonic...REFERENCES 1. Génin, F., Fryxell, B. and Menon, S., “Simulation of Detonation Propagation in Turbulent Gas- Solid Reactive Mixtures”, 41 st

Hole-Accepting-Ligand-Modified CdSe QDs for Dramatic Enhancement of Photocatalytic and Photoelectrochemical Hydrogen Evolution by Solar Energy.

PubMed

Li, Xu-Bing; Liu, Bin; Wen, Min; Gao, Yu-Ji; Wu, Hao-Lin; Huang, Mao-Yong; Li, Zhi-Jun; Chen, Bin; Tung, Chen-Ho; Wu, Li-Zhu

2016-04-01

Solar H 2 evolution of CdSe QDs can be significantly enhanced simply by introducing a suitable hole-accepting-ligand for achieving efficient hole extraction and transfer at the nanoscale interfaces, which opens an effective pathway for dissociation of excitons to generate long-lived charge separation, thus improving the solar-to-fuel conversion efficiency.

Dramatically enhanced non-Ohmic properties and maximum stored energy density in ceramic-metal nanocomposites: CaCu3Ti4O12/Au nanoparticles

PubMed Central

2013-01-01

Non-Ohmic and dielectric properties of a novel CaCu3Ti4O12/Au nanocomposite were investigated. Introduction of 2.5 vol.% Au nanoparticles in CaCu3Ti4O12 ceramics significantly reduced the loss tangent while its dielectric permittivity remained unchanged. The non-Ohmic properties of CaCu3Ti4O12/Au (2.5 vol.%) were dramatically improved. A nonlinear coefficient of ≈ 17.7 and breakdown electric field strength of 1.25 × 104 V/m were observed. The maximum stored energy density was found to be 25.8 kJ/m3, which is higher than that of pure CaCu3Ti4O12 by a factor of 8. Au addition at higher concentrations resulted in degradation of dielectric and non-Ohmic properties, which is described well by percolation theory. PMID:24257060

Graphene for batteries, supercapacitors and beyond

NASA Astrophysics Data System (ADS)

El-Kady, Maher F.; Shao, Yuanlong; Kaner, Richard B.

2016-07-01

Graphene has recently enabled the dramatic improvement of portable electronics and electric vehicles by providing better means for storing electricity. In this Review, we discuss the current status of graphene in energy storage and highlight ongoing research activities, with specific emphasis placed on the processing of graphene into electrodes, which is an essential step in the production of devices. We calculate the maximum energy density of graphene supercapacitors and outline ways for future improvements. We also discuss the synthesis and assembly of graphene into macrostructures, ranging from 0D quantum dots, 1D wires, 2D sheets and 3D frameworks, to potentially 4D self-folding materials that allow the design of batteries and supercapacitors with many new features that do not exist in current technology.

Not Your Normal Power Box

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okman, Oya; Baginska, Marta; Jones, Elizabeth MC

Representing the Center for Electrical Energy Storage (CEES), this document is one of the entries in the Ten Hundred and One Word Challenge and was awarded "Best Science Lesson." 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 CEES is to acquire a fundamentalmore » understanding of interfacial phenomena controlling electrochemical processes that will enable dramatic improvements in the properties and performance of energy storage devices, notably Li ion batteries.« less

Radiative contribution to thermal conductance in animal furs and other woolly insulators.

PubMed

Simonis, Priscilla; Rattal, Mourad; Oualim, El Mostafa; Mouhse, Azeddine; Vigneron, Jean-Pol

2014-01-27

This paper deals with radiation's contribution to thermal insulation. The mechanism by which a stack of absorbers limits radiative heat transfer is examined in detail both for black-body shields and grey-body shields. It shows that radiation energy transfer rates should be much faster than conduction rates. It demonstrates that, for opaque screens, increased reflectivity will dramatically reduce the rate of heat transfer, improving thermal insulation. This simple model is thought to contribute to the understanding of how animal furs, human clothes, rockwool insulators, thermo-protective containers, and many other passive energy-saving devices operate.

Fluctuating local field method probed for a description of small classical correlated lattices

NASA Astrophysics Data System (ADS)

Rubtsov, Alexey N.

2018-05-01

Thermal-equilibrated finite classical lattices are considered as a minimal model of the systems showing an interplay between low-energy collective fluctuations and single-site degrees of freedom. Standard local field approach, as well as classical limit of the bosonic DMFT method, do not provide a satisfactory description of Ising and Heisenberg small lattices subjected to an external polarizing field. We show that a dramatic improvement can be achieved within a simple approach, in which the local field appears to be a fluctuating quantity related to the low-energy degree(s) of freedom.

The role of ablative lasers in cutaneous scars: tissue regeneration to restore function (Conference Presentation)

NASA Astrophysics Data System (ADS)

Uebelhoer, Nathan

2017-02-01

Many laser wavelengths with various power and pulse characteristics have been used in an attempt to improve cutaneous scars. No single configuration has produced such dramatic changes in quality of life as the high energy, low density, sub-millisecond pulsed ablative infrared laser. Hundreds of wounded military service members with burn and traumatic scars that resulted in disabling restriction in range of motion have been treated since 2008. By fractionating the pulse to produce a uniform thermal injury less than 400um wide and to a depth of 3mm into the scar, we have observed dramatic reductions in scar-induced pain, pruritus, and most significantly, improvements in range of motion. The clinical and histologic changes seen in restrictive scars following treatment correlates with a regeneration of tissue that appears and functions more like normal tissue rather than scar. This lecture will describe our experience in the military and the latest research to support our observations.

Improving Sustainability of Ion Implant Modules

NASA Astrophysics Data System (ADS)

Mayer, Jim

2011-01-01

Semiconductor fabs have long been pressured to manage capital costs, reduce energy consumption and increasingly improve efforts to recycle and recover resources. Ion implant tools have been high-profile offenders on all three fronts. They draw such large volumes of air for heat dissipation and risk reduction that historically, they are the largest consumer of cleanroom air of any process tool—and develop energy usage and resource profiles to match. This paper presents a documented approach to reduce their energy consumption and dramatically downsize on-site facilities support for cleanroom air manufacture and abatement. The combination produces significant capital expenditure savings. The case entails applying SAGS Type 1 (sub-atmospheric gas systems) toxic gas packaging to enable engineering adaptations that deliver the energy savings and cost benefits without any reduction in environmental health and safety. The paper also summarizes benefits as they relate to reducing a fabs carbon emission footprint (and longer range advantages relative to potential cap and trade programs) with existing technology.

Home in the heat: Dramatic seasonal variation in home range of desert golden eagles informs management for renewable energy development

Treesearch

Melissa Braham; Tricia Miller; Adam E. Duerr; Michael Lanzone; Amy Fesnock; Larry LaPre; Daniel Driscoll; Todd Katzner

2015-01-01

Renewable energy is expanding quickly with sometimes dramatic impacts to species and ecosystems. To understand the degree to which sensitive species may be impacted by renewable energy projects, it is informative to know how much space individuals use and how that space may overlap with planned development. We used global positioning system-global system for mobile...

Microalgal hydrogen production: prospects of an essential technology for a clean and sustainable energy economy.

PubMed

Bayro-Kaiser, Vinzenz; Nelson, Nathan

2017-09-01

Modern energy production is required to undergo a dramatic transformation. It will have to replace fossil fuel use by a sustainable and clean energy economy while meeting the growing world energy needs. This review analyzes the current energy sector, available energy sources, and energy conversion technologies. Solar energy is the only energy source with the potential to fully replace fossil fuels, and hydrogen is a crucial energy carrier for ensuring energy availability across the globe. The importance of photosynthetic hydrogen production for a solar-powered hydrogen economy is highlighted and the development and potential of this technology are discussed. Much successful research for improved photosynthetic hydrogen production under laboratory conditions has been reported, and attempts are underway to develop upscale systems. We suggest that a process of integrating these achievements into one system to strive for efficient sustainable energy conversion is already justified. Pursuing this goal may lead to a mature technology for industrial deployment.

Misconceptions of Electric Propulsion Aircraft and Their Emergent Aviation Markets

NASA Technical Reports Server (NTRS)

Moore, Mark D.; Fredericks, Bill

2014-01-01

Over the past several years there have been aircraft conceptual design and system studies that have reached conflicting conclusions relating to the feasibility of full and hybrid electric aircraft. Some studies and propulsion discipline experts have claimed that battery technologies will need to improve by 10 to 20 times before electric aircraft can effectively compete with reciprocating or turbine engines. However, such studies have approached comparative assessments without understanding the compelling differences that electric propulsion offers, how these technologies will fundamentally alter the way propulsion integration is approached, or how these new technologies can not only compete but far exceed existing propulsion solutions in many ways at battery specific energy densities of only 400 watt hours per kilogram. Electric propulsion characteristics offer the opportunity to achieve 4 to 8 time improvements in energy costs with dramatically lower total operating costs, while dramatically improving efficiency, community noise, propulsion system reliability and safety through redundancy, as well as life cycle Green House Gas emissions. Integration of electric propulsion will involve far greater degrees of distribution than existing propulsion solutions due to their compact and scale-free nature to achieve multi-disciplinary coupling and synergistic integration with the aerodynamics, highlift system, acoustics, vehicle control, balance, and aeroelasticity. Appropriate metrics of comparison and differences in analysis/design tools are discussed while comparing electric propulsion to other disruptive technologies. For several initial applications, battery energy density is already sufficient for competitive products, and for many additional markets energy densities will likely be adequate within the next 7 years for vibrant introduction. Market evolution and early adopter markets are discussed, along with the investment areas that will fill technology gaps and create opportunities for the effective, near-term electric aircraft products. Without understanding both the context of how electric propulsion will integrate into the vehicle system, and evolve into the market place it is likely that electric propulsion will continue to be misunderstood.

A new cooperative MIMO scheme based on SM for energy-efficiency improvement in wireless sensor network.

PubMed

Peng, Yuyang; Choi, Jaeho

2014-01-01

Improving the energy efficiency in wireless sensor networks (WSN) has attracted considerable attention nowadays. The multiple-input multiple-output (MIMO) technique has been proved as a good candidate for improving the energy efficiency, but it may not be feasible in WSN which is due to the size limitation of the sensor node. As a solution, the cooperative multiple-input multiple-output (CMIMO) technique overcomes this constraint and shows a dramatically good performance. In this paper, a new CMIMO scheme based on the spatial modulation (SM) technique named CMIMO-SM is proposed for energy-efficiency improvement. We first establish the system model of CMIMO-SM. Based on this model, the transmission approach is introduced graphically. In order to evaluate the performance of the proposed scheme, a detailed analysis in terms of energy consumption per bit of the proposed scheme compared with the conventional CMIMO is presented. Later, under the guide of this new scheme we extend our proposed CMIMO-SM to a multihop clustered WSN for further achieving energy efficiency by finding an optimal hop-length. Equidistant hop as the traditional scheme will be compared in this paper. Results from the simulations and numerical experiments indicate that by the use of the proposed scheme, significant savings in terms of total energy consumption can be achieved. Combining the proposed scheme with monitoring sensor node will provide a good performance in arbitrary deployed WSN such as forest fire detection system.

Intelligent buildings.

PubMed

Williams, W E

1987-01-01

The maturing of technologies in computer capabilities, particularly direct digital signals, has provided an exciting variety of new communication and facility control opportunities. These include telecommunications, energy management systems, security systems, office automation systems, local area networks, and video conferencing. New applications are developing continuously. The so-called "intelligent" or "smart" building concept evolves from the development of this advanced technology in building environments. Automation has had a dramatic effect on facility planning. For decades, communications were limited to the telephone, the typewritten message, and copy machines. The office itself and its functions had been essentially unchanged for decades. Office automation systems began to surface during the energy crisis and, although their newer technology was timely, they were, for the most part, designed separately from other new building systems. For example, most mainframe computer systems were originally stand-alone, as were word processing installations. In the last five years, the advances in distributive systems, networking, and personal computer capabilities have provided opportunities to make such dramatic improvements in productivity that the Selectric typewriter has gone from being the most advanced piece of office equipment to nearly total obsolescence.

Creating Lithium-Ion Electrolytes with Biomimetic Ionic Channels in Metal-Organic Frameworks.

PubMed

Shen, Li; Wu, Hao Bin; Liu, Fang; Brosmer, Jonathan L; Shen, Gurong; Wang, Xiaofeng; Zink, Jeffrey I; Xiao, Qiangfeng; Cai, Mei; Wang, Ge; Lu, Yunfeng; Dunn, Bruce

2018-06-01

Solid-state electrolytes are the key to the development of lithium-based batteries with dramatically improved energy density and safety. Inspired by ionic channels in biological systems, a novel class of pseudo solid-state electrolytes with biomimetic ionic channels is reported herein. This is achieved by complexing the anions of an electrolyte to the open metal sites of metal-organic frameworks (MOFs), which transforms the MOF scaffolds into ionic-channel analogs with lithium-ion conduction and low activation energy. This work suggests the emergence of a new class of pseudo solid-state lithium-ion conducting electrolytes. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fixed Wing Project: Technologies for Advanced Air Transports

NASA Technical Reports Server (NTRS)

Del Rosario, Ruben; Koudelka, John M.; Wahls, Richard A.; Madavan, Nateri

2014-01-01

The NASA Fundamental Aeronautics Fixed Wing (FW) Project addresses the comprehensive challenge of enabling revolutionary energy efficiency improvements in subsonic transport aircraft combined with dramatic reductions in harmful emissions and perceived noise to facilitate sustained growth of the air transportation system. Advanced technologies and the development of unconventional aircraft systems offer the potential to achieve these improvements. Multidisciplinary advances are required in aerodynamic efficiency to reduce drag, structural efficiency to reduce aircraft empty weight, and propulsive and thermal efficiency to reduce thrust-specific energy consumption (TSEC) for overall system benefit. Additionally, advances are required to reduce perceived noise without adversely affecting drag, weight, or TSEC, and to reduce harmful emissions without adversely affecting energy efficiency or noise.The presentation will highlight the Fixed Wing project vision of revolutionary systems and technologies needed to achieve these challenging goals. Specifically, the primary focus of the FW Project is on the N+3 generation; that is, vehicles that are three generations beyond the current state of the art, requiring mature technology solutions in the 2025-30 timeframe.

Improved dielectric constant and breakdown strength of γ-phase dominant super toughened polyvinylidene fluoride/TiO2 nanocomposite film: an excellent material for energy storage applications and piezoelectric throughput

NASA Astrophysics Data System (ADS)

Mehebub Alam, Md; Ghosh, Sujoy Kumar; Sarkar, Debabrata; Sen, Shrabanee; Mandal, Dipankar

2017-01-01

Titanium dioxide (TiO2) nanoparticles (NPs) embedded γ-phase containing polyvinylidene fluoride (PVDF) nanocomposite (PNC) film turns to an excellent material for energy storage application due to an increased dielectric constant (32 at 1 kHz), enhanced electric breakdown strength (400 MV m-1). It also exhibits a high energy density of 4 J cm-3 which is 25 times higher than that of virgin PVDF. 98% of the electroactive γ-phase has been acheived by the incorporation of TiO2 NPs and the resulting PNC behaves like a super-toughened material due to a dramatic improvement (more than 80%) in the tensile strength. Owing to their electroactive nature and extraordinary mechanical properties, PNC films have a strong ability to fabricate the piezoelectric nanogenerators (PNGs) that have recently been an area of focus regarding mechanical energy harvesting. The feasibility of piezoelectric voltage generation from PNGs is demostrated under the rotating fan that also promises further utility such as rotational speed (RPM) determination.

Surface nanocrystalline and hardening effects of Ti-Al-V alloy by electropulsing ultrasonic shock

NASA Astrophysics Data System (ADS)

Ye, Xiaoxin

2015-04-01

The effect of electropulsing ultrasonic shock (EUS) on the surface hardening and microstructure of Ti6Al4V alloy was studied. It was found that electropulsing improved the microhardness dramatically both in the influential depth and maximum value, compared with the only ultrasonic-shocked sample. It's indicated that refined surface layer with nanocrystalline and improved microhardness were obtained on account of surface severe plastic deformation, dynamic recrystallization (DRX) and phase change, which was implemented at relative low temperature and high strain rate/capacity due to the coupling of the thermal and athermal effects of EUS. It's different from conventional experiments and theory. It's discussed that the positive contributions of EPT in the thermodynamics and kinetics of microstructure and properties change were attributed to the reduction of nucleation energy barrier and acceleration of atomic diffusion. Therefore, it's supposed that EUS is an energy-saving and high-efficiency method of surface treatment technique with the help of high-energy electropulses, which is promising in cost reduction of the surface engineering and energy management.

Probing the Inelastic Interactions in Molecular Junctions by Scanning Tunneling Microscope

NASA Astrophysics Data System (ADS)

Xu, Chen

With a sub-Kelvin scanning tunneling microscope, the energy resolution of spectroscopy is improved dramatically. Detailed studies of finer features of spectrum become possible. The asymmetry in the line shape of carbon monoxide vibrational spectra is observed to correlate with the couplings of the molecule to the tip and substrates. The spin-vibronic coupling in the molecular junctions is revisited with two metal phthalocyanine molecules, unveiling sharp spin-vibronic peaks. Finally, thanks to the improved spectrum resolution, the bonding structure of the acyclic compounds molecules is surveyed with STM inelastic tunneling probe, expanding the capability of the innovative high resolution imaging technique.

The vacuum system reform and test of the super-critical 600mw unit

NASA Astrophysics Data System (ADS)

Yan, Tao; Wan, Zhonghai; Lu, Jin; Chen, Wen; Cai, Wen

2017-11-01

The deficiencies of the designed vacuum system of the super-critical unit is pointed out in this paper, and then it is reformed by the steam ejector. The experimental results show that the vacuum of the condenser can be improved, the coal consumption can be reduced and the plant electricity consumption can be lowered dramatically at a small cost of the steam energy consumption. Meanwhile, the water-ring vacuum pumps cavitation problems can be solved.

The Hybrid Automobile and the Atkinson Cycle

NASA Astrophysics Data System (ADS)

Feldman, Bernard J.

2008-10-01

The hybrid automobile is a strikingly new automobile technology with a number of new technological features that dramatically improve energy efficiency. This paper will briefly describe how hybrid automobiles work; what are these new technological features; why the Toyota Prius hybrid internal combustion engine operates on the Atkinson cycle instead of the Otto cycle; and what are the advantages and disadvantages of the hybrid automobile. This is a follow-up to my two previous papers on the physics of automobile engines.1,2

MCTDH on-the-fly: Efficient grid-based quantum dynamics without pre-computed potential energy surfaces

NASA Astrophysics Data System (ADS)

Richings, Gareth W.; Habershon, Scott

2018-04-01

We present significant algorithmic improvements to a recently proposed direct quantum dynamics method, based upon combining well established grid-based quantum dynamics approaches and expansions of the potential energy operator in terms of a weighted sum of Gaussian functions. Specifically, using a sum of low-dimensional Gaussian functions to represent the potential energy surface (PES), combined with a secondary fitting of the PES using singular value decomposition, we show how standard grid-based quantum dynamics methods can be dramatically accelerated without loss of accuracy. This is demonstrated by on-the-fly simulations (using both standard grid-based methods and multi-configuration time-dependent Hartree) of both proton transfer on the electronic ground state of salicylaldimine and the non-adiabatic dynamics of pyrazine.

FY 2007 Progress Report for Advanced Combustion Engine Technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

None, None

2007-12-01

Advanced combustion engines have great potential for achieving dramatic energy efficiency improvements in light-duty vehicle applications, where it is suited to both conventional and hybrid- electric powertrain configurations. Light-duty vehicles with advanced combustion engines can compete directly with gasoline engine hybrid vehicles in terms of fuel economy and consumer-friendly driving characteristics; also, they are projected to have energy efficiencies that are competitive with hydrogen fuel cell vehicles when used in hybrid applications.Advanced engine technologies being researched and developed by the Advanced Combustion Engine R&D Sub-Program will also allow the use of hydrogen as a fuel in ICEs and will providemore » an energy-efficient interim hydrogen-based powertrain technology during the transition to hydrogen/fuelcell-powered transportation vehicles.« less

Phosphoinositides: Key modulators of energy metabolism☆

PubMed Central

Bridges, Dave; Saltiel, Alan R.

2014-01-01

Phosphoinositides are key players in many trafficking and signaling pathways. Recent advances regarding the synthesis, location and functions of these lipids have dramatically improved our understanding of how and when these lipids are generated and what their roles are in animal physiology. In particular, phosphoinositides play a central role in insulin signaling, and manipulation of PtdIns(3,4,5)P3 levels in particular, may be an important potential therapeutic target for the alleviation of insulin resistance associated with obesity and the metabolic syndrome. In this article we review the metabolism, regulation and functional roles of phosphoinositides in insulin signaling and the regulation of energy metabolism. This article is part of a Special Issue entitled Phosphoinositides. PMID:25463477

ZnO buffer layer for metal films on silicon substrates

DOEpatents

Ihlefeld, Jon

2014-09-16

Dramatic improvements in metallization integrity and electroceramic thin film performance can be achieved by the use of the ZnO buffer layer to minimize interfacial energy between metallization and adhesion layers. In particular, the invention provides a substrate metallization method utilizing a ZnO adhesion layer that has a high work of adhesion, which in turn enables processing under thermal budgets typically reserved for more exotic ceramic, single-crystal, or metal foil substrates. Embodiments of the present invention can be used in a broad range of applications beyond ferroelectric capacitors, including microelectromechanical systems, micro-printed heaters and sensors, and electrochemical energy storage, where integrity of metallized silicon to high temperatures is necessary.

A dramatic, objective antiandrogen withdrawal response: case report and review of the literature.

PubMed

Lau, Yiu-Keung; Chadha, Manpreet K; Litwin, Alan; Trump, Donald L

2008-11-05

Antiandrogen withdrawal response is an increasingly recognized entity in patients with metastatic prostate cancer. To our knowledge, there have been no reports describing a durable radiologic improvement along with prostate-specific antigen (PSA) with discontinuation of the antiandrogen agent bicalutamide. We report a case in which a dramatic decline of serum PSA levels associated with a dramatic improvement in radiologic disease was achieved with bicalutamide discontinuation.

A low energy demand scenario for meeting the 1.5 °C target and sustainable development goals without negative emission technologies

NASA Astrophysics Data System (ADS)

Grubler, Arnulf; Wilson, Charlie; Bento, Nuno; Boza-Kiss, Benigna; Krey, Volker; McCollum, David L.; Rao, Narasimha D.; Riahi, Keywan; Rogelj, Joeri; De Stercke, Simon; Cullen, Jonathan; Frank, Stefan; Fricko, Oliver; Guo, Fei; Gidden, Matt; Havlík, Petr; Huppmann, Daniel; Kiesewetter, Gregor; Rafaj, Peter; Schoepp, Wolfgang; Valin, Hugo

2018-06-01

Scenarios that limit global warming to 1.5 °C describe major transformations in energy supply and ever-rising energy demand. Here, we provide a contrasting perspective by developing a narrative of future change based on observable trends that results in low energy demand. We describe and quantify changes in activity levels and energy intensity in the global North and global South for all major energy services. We project that global final energy demand by 2050 reduces to 245 EJ, around 40% lower than today, despite rises in population, income and activity. Using an integrated assessment modelling framework, we show how changes in the quantity and type of energy services drive structural change in intermediate and upstream supply sectors (energy and land use). Down-sizing the global energy system dramatically improves the feasibility of a low-carbon supply-side transformation. Our scenario meets the 1.5 °C climate target as well as many sustainable development goals, without relying on negative emission technologies.

External priors for the next generation of CMB experiments

DOE PAGES

Manzotti, Alessandro; Dodelson, Scott; Park, Youngsoo

2016-03-28

Planned cosmic microwave background (CMB) experiments can dramatically improve what we know about neutrino physics, inflation, and dark energy. The low level of noise, together with improved angular resolution, will increase the signal to noise of the CMB polarized signal as well as the reconstructed lensing potential of high redshift large scale structure. Projected constraints on cosmological parameters are extremely tight, but these can be improved even further with information from external experiments. Here, we examine quantitatively the extent to which external priors can lead to improvement in projected constraints from a CMB-Stage IV (S4) experiment on neutrino and dark energy properties. We find that CMB S4 constraints on neutrino mass could be strongly enhanced by external constraints on the cold dark matter densitymore » $$\\Omega_{c}h^{2}$$ and the Hubble constant $$H_{0}$$. If polarization on the largest scales ($$\\ell<50$$) will not be measured, an external prior on the primordial amplitude $$A_{s}$$ or the optical depth $$\\tau$$ will also be important. A CMB constraint on the number of relativistic degrees of freedom, $$N_{\\rm eff}$$, will benefit from an external prior on the spectral index $$n_{s}$$ and the baryon energy density $$\\Omega_{b}h^{2}$$. Lastly, an external prior on $$H_{0}$$ will help constrain the dark energy equation of state ($w$).« less

Research on Impact Stress and Fatigue Simulation of a New Down-to-the-Hole Impactor Based on ANSYS

NASA Astrophysics Data System (ADS)

Wu, Tao; Wang, Wei; Yao, Aiguo; Li, Yongbo; He, Wangyong; Fei, Dongdong

2018-06-01

In the present work, a down-to-the-hole electric hammer driven by linear motor is reported for drilling engineering. It differs from the common hydraulic or pneumatic hammers in that it can be applied to some special occasions without circulating medium due to its independence of the drilling fluid. The impact stress caused by the reciprocating motion between stator and rotor and the fatigue damage in key components of linear motor are analyzed by the ANSYS Workbench software and 3D model. Based on simulation results, the hammer's structure is optimized by using special sliding bearing, increasing the wall thickness of key and multilayer buffer gasket. Fatigue life and coefficient issues of the new structure are dramatically improved. However buffer gasket reduces the impactor's energy, different bumper structure effect on life improving and energy loss have also been elaborated.

Improving Energy Efficiency Via Optimized Charge Motion and Slurry Flow in Plant Scale Sag Mills

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raj K. Rajamani

2006-07-21

A research team from the University of Utah is working to make inroads into saving energy in these SAG mills. In 2003, Industries of the Future Program of the Department of Energy tasked the University of Utah team to build a partnership between the University and the mining industry for the specific purpose of reducing energy consumption in SAG mills. A partnership was formed with Cortez Gold Mines, Outokumpu Technology, Kennecott Utah Copper Corporation, and Process Engineering Resources Inc. At Cortez Gold Operations the shell and pulp lifters of the semiautogenous grinding mill was redesigned. The redesigned shell lifter hasmore » been in operation for over three years and the redesigned pulp lifter has been in operation for over nine months now. This report summarizes the dramatic reductions in energy consumption. Even though the energy reductions are very large, it is safe to say that a 20% minimum reduction would be achieved in any future installations of this technology.« less

Results on the energy dependence of cosmic-ray charge composition

NASA Technical Reports Server (NTRS)

Balasubrahmanyan, V. K.; Ormes, J. F.

1973-01-01

Results of measurements by a balloon-borne ionization spectrometer of the energy dependence of high-energy cosmic-ray charge composition. The results presented are greatly improved over those obtained earlier by Ormes et al. (1971) by the use of a multidimensional charge analysis with more efficient background rejection, and a more accurate energy determination. Complex couplings between the charge, energy, and trajectory information were taken into account and are discussed. The spectra of individual elements up to oxygen and of groups of nuclei up through iron were measured up to almost 100 GeV per nucleon. The energy spectrum of the secondary nuclei, B + N, is found to be steeper than that of the primary nuclei, C + O, in agreement with Smith et al. (1973). The most dramatic finding is that the spectrum of the iron nuclei is flatter than that of the carbon and oxygen nuclei by 0.57 plus or minus 0.14 of a power.

Limiting factors for carbon based chemical double layer capacitors

NASA Technical Reports Server (NTRS)

Rose, M. Frank; Johnson, C.; Owens, T.; Stevens, B.

1993-01-01

The Chemical Double Layer (CDL) capacitor improves energy storage density dramatically when compared with conventional electrolytic capacitors. When compared to batteries, the CDL Capacitor is much less energy dense; however, the power density is orders of magnitude better. As a result, CDL-battery combinations present an interesting pulse power system with many potential applications. Due to the nature of the CDL it is inherently a low voltage device. The applications of the CDL can be tailored to auxiliary energy and burst mode storages which require fast charge/discharge cycles. Typical of the applications envisioned are power system backup, directed energy weapons concepts, electric automobiles, and electric actuators. In this paper, we will discuss some of the general characteristics of carbon-based CDL technology describing the structure, performance parameters, and methods of construction. Further, analytical and experimental results which define the state of the art are presented and described in terms of impact on applications.

Fast and efficient STT switching in MTJ using additional transient pulse current

NASA Astrophysics Data System (ADS)

Pathak, Sachin; Cha, Jongin; Jo, Kangwook; Yoon, Hongil; Hong, Jongill

2017-06-01

We propose a profile of write pulse current-density to switch magnetization in a perpendicular magnetic tunnel junction to reduce switching time and write energy as well. Our simulated results show that an overshoot transient pulse current-density (current spike) imposed to conventional rectangular-shaped pulse current-density (main pulse) significantly improves switching speed that yields the reduction in write energy accordingly. For example, we could dramatically reduce the switching time by 80% and thereby reduce the write energy over 9% in comparison to the switching without current spike. The current spike affects the spin dynamics of the free layer and reduces the switching time mainly due to spin torque induced. On the other hand, the large Oersted field induced causes changes in spin texture. We believe our proposed write scheme can make a breakthrough in magnetic random access memory technology seeking both high speed operation and low energy consumption.

All Solid State Rechargeable Lithium Batteries using Block Copolymers

NASA Astrophysics Data System (ADS)

Hallinan, Daniel; Balsara, Nitash

2011-03-01

The growing need for alternative energy and increased demand for mobile technology require higher density energy storage. Existing battery technologies, such as lithium ion, are limited by theoretical energy density as well as safety issues. Other battery chemistries are promising options for dramatically increasing energy density. Safety can be improved by replacing the flammable, reactive liquids used in existing lithium-ion battery electrolytes with polymer electrolytes. Block copolymers are uniquely suited for this task because ionic conductivity and mechanical strength, both important properties in battery formulation, can be independently controlled. In this study, lithium batteries were assembled using lithium metal as negative electrode, polystyrene-b-poly(ethylene oxide) copolymer with lithium salt as electrolyte, and a positive electrode. The positive electrode consisted of polymer electrolyte for ion conduction, carbon for electron conduction, and an active material. Batteries were charged and discharged over many cycles. The battery cycling results were compared to a conventional battery chemistry.

Significant improvement in Mn2O3 transition metal oxide electrical conductivity via high pressure

PubMed Central

Hong, Fang; Yue, Binbin; Hirao, Naohisa; Liu, Zhenxian; Chen, Bin

2017-01-01

Highly efficient energy storage is in high demand for next-generation clean energy applications. As a promising energy storage material, the application of Mn2O3 is limited due to its poor electrical conductivity. Here, high-pressure techniques enhanced the electrical conductivity of Mn2O3 significantly. In situ synchrotron micro X-Ray diffraction, Raman spectroscopy and resistivity measurement revealed that resistivity decreased with pressure and dramatically dropped near the phase transition. At the highest pressure, resistivity reduced by five orders of magnitude and the sample showed metal-like behavior. More importantly, resistivity remained much lower than its original value, even when the pressure was fully released. This work provides a new method to enhance the electronic properties of Mn2O3 using high-pressure treatment, benefiting its applications in energy-related fields. PMID:28276479

Sustainable energy, economic growth and public health.

PubMed

Haines, A

2001-01-01

Dramatic economic growth over the last 50 years has been accompanied by widening inequalities world-wide in wealth and energy consumption, diminished life expectancy in some countries, and deteriorating indices of environmental sustainability including loss of bio-diversity. Raised output of carbon dioxide (CO2) and other greenhouse gases due to increased economic and industrial activity is causing progressive climate change, leading in turn to direct and indirect adverse effects on health. Emissions of greenhouse gases can be lowered by increased use of renewable energy sources, for example, wind power in the United Kingdom (UK), greater energy efficiency and other measures to promote sustainability. The experience of some developing countries shows that favourable indicators of health and development can accompany a low output of greenhouse gases. It is unclear whether contemporary political and social systems can deliver improved human development without increased use of fossil fuels and other resources.

Restoration of metabolic health by decreased consumption of branched-chain amino acids.

PubMed

Cummings, Nicole E; Williams, Elizabeth M; Kasza, Ildiko; Konon, Elizabeth N; Schaid, Michael D; Schmidt, Brian A; Poudel, Chetan; Sherman, Dawn S; Yu, Deyang; Arriola Apelo, Sebastian I; Cottrell, Sara E; Geiger, Gabriella; Barnes, Macy E; Wisinski, Jaclyn A; Fenske, Rachel J; Matkowskyj, Kristina A; Kimple, Michelle E; Alexander, Caroline M; Merrins, Matthew J; Lamming, Dudley W

2018-02-15

We recently found that feeding healthy mice a diet with reduced levels of branched-chain amino acids (BCAAs), which are associated with insulin resistance in both humans and rodents, modestly improves glucose tolerance and slows fat mass gain. In the present study, we show that a reduced BCAA diet promotes rapid fat mass loss without calorie restriction in obese mice. Selective reduction of dietary BCAAs also restores glucose tolerance and insulin sensitivity to obese mice, even as they continue to consume a high-fat, high-sugar diet. A low BCAA diet transiently induces FGF21 (fibroblast growth factor 21) and increases energy expenditure. We suggest that dietary protein quality (i.e. the precise macronutrient composition of dietary protein) may impact the effectiveness of weight loss diets. Obesity and diabetes are increasing problems around the world, and although even moderate weight loss can improve metabolic health, reduced calorie diets are notoriously difficult to sustain. Branched-chain amino acids (BCAAs; leucine, isoleucine and valine) are elevated in the blood of obese, insulin-resistant humans and rodents. We recently demonstrated that specifically reducing dietary levels of BCAAs has beneficial effects on the metabolic health of young, growing mice, improving glucose tolerance and modestly slowing fat mass gain. In the present study, we examine the hypothesis that reducing dietary BCAAs will promote weight loss, reduce adiposity, and improve blood glucose control in diet-induced obese mice with pre-existing metabolic syndrome. We find that specifically reducing dietary BCAAs rapidly reverses diet-induced obesity and improves glucoregulatory control in diet-induced obese mice. Most dramatically, mice eating an otherwise unhealthy high-calorie, high-sugar Western diet with reduced levels of BCAAs lost weight and fat mass rapidly until regaining a normal weight. Importantly, this normalization of weight was mediated not by caloric restriction or increased activity, but by increased energy expenditure, and was accompanied by a transient induction of the energy balance regulating hormone FGF21 (fibroblast growth factor 21). Consumption of a Western diet reduced in BCAAs was also accompanied by a dramatic improvement in glucose tolerance and insulin resistance. Our results link dietary BCAAs with the regulation of metabolic health and energy balance in obese animals, and suggest that specifically reducing dietary BCAAs may represent a highly translatable option for the treatment of obesity and insulin resistance. © 2017 The Authors. The Journal of Physiology © 2017 The Physiological Society.

Weizsäcker-Skyrme-type nuclear mass formula incorporating two combinatorial radial basis function prescriptions and their application

NASA Astrophysics Data System (ADS)

Ma, Na Na; Zhang, Hai Fei; Yin, Peng; Bao, Xiao Jun; Zhang, Hong Fei

2017-08-01

Within the improved Weizsäcker-Skyrme (WS)-type nuclear mass formulas, we systematically calculated one-nucleon and two-nucleon separated energy, α-decay and β-decay energies, and the odd-even staggering (OES) of nuclear binding energies. As a result, the root-mean-square (rms) deviations of 2267 nuclei within the new improved WS-type mass formula are dropped from 493 to 167 keV, where 2267 nuclei are extracted from the atomic mass evaluation of 2012. Simultaneously, all the rms deviations of one-nucleon and two-nucleon separation energies and decay energies Qα,Qβ-,Qβ+, and QEC for more than 3000 nuclei are cut down by about 100-400 keV. Further, some basic physical observations of 988 boundary nuclei are predicted for providing reference to experiments. Finally, the overall neutron OESs and proton OESs have been systemically investigated and the residual error satisfies a normal distribution. The pairing gaps Δn and Δp of the isotopes of O, Ca, Ni, Zr, Sn, Gd, Qs, Pb, Pa, Ds and the isotonic magic chains of N =28 ,50 ,82 ,126 and even-even nuclei are also studied with dramatic improvements obtained. Especially, the rms of Δn and Δp in these nuclei have been reduced by about 200 keV. The above physical quantities show important information for nuclear charts and the features of nuclear structure.

A dramatic, objective antiandrogen withdrawal response: case report and review of the literature

PubMed Central

Lau, Yiu-Keung; Chadha, Manpreet K; Litwin, Alan; Trump, Donald L

2008-01-01

Antiandrogen withdrawal response is an increasingly recognized entity in patients with metastatic prostate cancer. To our knowledge, there have been no reports describing a durable radiologic improvement along with prostate-specific antigen (PSA) with discontinuation of the antiandrogen agent bicalutamide. We report a case in which a dramatic decline of serum PSA levels associated with a dramatic improvement in radiologic disease was achieved with bicalutamide discontinuation. PMID:18986533

Use of microsecond current prepulse for dramatic improvements of wire array Z-pinch implosion

NASA Astrophysics Data System (ADS)

Calamy, H.; Lassalle, F.; Loyen, A.; Zucchini, F.; Chittenden, J. P.; Hamann, F.; Maury, P.; Georges, A.; Bedoch, J. P.; Morell, A.

2008-01-01

The Sphinx machine [F. Lassalle et al., "Status on the SPHINX machine based on the 1microsecond LTD technology"] based on microsecond linear transformer driver (LTD) technology is used to implode an aluminium wire array with an outer diameter up to 140mm and maximum current from 3.5to5MA. 700to800ns implosion Z-pinch experiments are performed on this driver essentially with aluminium. Best results obtained before the improvement described in this paper were 1-3TW radial total power, 100-300kJ total yield, and 20-30kJ energy above 1keV. An auxiliary generator was added to the Sphinx machine in order to allow a multi microsecond current to be injected through the wire array load before the start of the main current. Amplitude and duration of this current prepulse are adjustable, with maxima ˜10kA and 50μs. This prepulse dramatically changes the ablation phase leading to an improvement of the axial homogeneity of both the implosion and the final radiating column. Total power was multiplied by a factor of 6, total yield by a factor of 2.5 with a reproducible behavior. This paper presents experimental results, magnetohydrodynamic simulations, and analysis of the effect of such a long current prepulse.

Dramatic pretend play games uniquely improve emotional control in young children.

PubMed

Goldstein, Thalia R; Lerner, Matthew D

2017-09-15

Pretense is a naturally occurring, apparently universal activity for typically developing children. Yet its function and effects remain unclear. One theorized possibility is that pretense activities, such as dramatic pretend play games, are a possible causal path to improve children's emotional development. Social and emotional skills, particularly emotional control, are critically important for social development, as well as academic performance and later life success. However, the study of such approaches has been criticized for potential bias and lack of rigor, precluding the ability to make strong causal claims. We conducted a randomized, component control (dismantling) trial of dramatic pretend play games with a low-SES group of 4-year-old children (N = 97) to test whether such practice yields generalized improvements in multiple social and emotional outcomes. We found specific effects of dramatic play games only on emotional self-control. Results suggest that dramatic pretend play games involving physicalizing emotional states and traits, pretending to be animals and human characters, and engaging in pretend scenarios in a small group may improve children's emotional control. These findings have implications for the function of pretense and design of interventions to improve emotional control in typical and atypical populations. Further, they provide support for the unique role of dramatic pretend play games for young children, particularly those from low-income backgrounds. A video abstract of this article can be viewed at: https://youtu.be/2GVNcWKRHPk. © 2017 John Wiley & Sons Ltd.

Hybrid electro-optics and chipscale integration of electronics and photonics

NASA Astrophysics Data System (ADS)

Dalton, L. R.; Robinson, B. H.; Elder, D. L.; Tillack, A. F.; Johnson, L. E.

2017-08-01

Taken together, theory-guided nano-engineering of organic electro-optic materials and hybrid device architectures have permitted dramatic improvement of the performance of electro-optic devices. For example, the voltage-length product has been improved by nearly a factor of 104 , bandwidths have been extended to nearly 200 GHz, device footprints reduced to less than 200 μm2 , and femtojoule energy efficiency achieved. This presentation discusses the utilization of new coarse-grained theoretical methods and advanced quantum mechanical methods to quantitatively simulate the physical properties of new classes of organic electro-optic materials and to evaluate their performance in nanoscopic device architectures, accounting for the effect on chromophore ordering at interfaces in nanoscopic waveguides.

NASA Fixed Wing Project: Green Technologies for Future Aircraft Generation

NASA Technical Reports Server (NTRS)

DelRosario, Ruben

2014-01-01

The NASA Fundamental Aeronautics Fixed Wing (FW) Project addresses the comprehensive challenge of enabling revolutionary energy efficiency improvements in subsonic transport aircraft combined with dramatic reductions in harmful emissions and perceived noise to facilitate sustained growth of the air transportation system. Advances in multidisciplinary technologies and the development of unconventional aircraft systems offer the potential to achieve these improvements. The presentation will highlight the FW Project vision of revolutionary systems and technologies needed to achieve the challenging goals of aviation. Specifically, the primary focus of the FW Project is on the N+3 generation that is, vehicles that are three generations beyond the current state of the art, requiring mature technology solutions in the 2025-30 timeframe.

Development of the Advanced Energetic Pair Telescope (AdEPT) for Medium-Energy Gamma-Ray Astronomy

NASA Technical Reports Server (NTRS)

Hunter, Stanley D.; Bloser, Peter F.; Dion, Michael P.; McConnell, Mark L.; deNolfo, Georgia A.; Son, Seunghee; Ryan, James M.; Stecker, Floyd W.

2011-01-01

Progress in high-energy gamma-ray science has been dramatic since the launch of INTEGRAL, AGILE and FERMI. These instruments, however, are not optimized for observations in the medium-energy (approx.0.3< E(sub gamma)< approx.200 MeV) regime where many astrophysical objects exhibit unique, transitory behavior, such as spectral breaks, bursts, and flares. We outline some of the major science goals of a medium-energy mission. These science goals are best achieved with a combination of two telescopes, a Compton telescope and a pair telescope, optimized to provide significant improvements in angular resolution and sensitivity. In this paper we describe the design of the Advanced Energetic Pair Telescope (AdEPT) based on the Three-Dimensional Track Imager (3-DTI) detector. This technology achieves excellent, medium-energy sensitivity, angular resolution near the kinematic limit, and gamma-ray polarization sensitivity, by high resolution 3-D electron tracking. We describe the performance of a 30x30x30 cm3 prototype of the AdEPT instrument.

Surface nanocrystalline and hardening effects of Ti-Al-V alloy by electropulsing ultrasonic shock

NASA Astrophysics Data System (ADS)

Ye, Xiaoxin; Tang, Guoyi

2015-03-01

The effect of electropulsing ultrasonic shock (EUS) on the surface hardening and microstructure of Ti6Al4V alloy was studied. It was found that electropulsing improved the microhardness dramatically both in the influential depth and maximum value, compared with the only ultrasonic-shocked sample. It's indicated that refined surface layer with nanocrystalline and improved microhardness were obtained on account of surface severe plastic deformation, dynamic recrystallization (DRX) and phase change, which was implemented at relative low temperature and high strain rate/capacity due to the coupling of the thermal and athermal effects of EUS. It's different from conventional experiments and theory. It's discussed that the positive contributions of EPT in the thermodynamics and kinetics of microstructure and properties change were attributed to the reduction of nucleation energy barrier and acceleration of atomic diffusion. Therefore, it's supposed that EUS is an energy-saving and high-efficiency method of surface treatment technique with the help of high-energy electropulses, which is promising in cost reduction of the surface engineering and energy management. The work is supported by National Natural Science Foundation of China (No. 50571048) and Shenzhen science and technology research funding project of China (No. SGLH20121008144756946).

How Energy Efficiency is Adding Jobs in St. Paul, Minnesota

ScienceCinema

Hannigan, Jim; Coleman, Chris; Oliver, LeAnn; Jambois, Louis

2018-02-07

Saint Paul, Minnesota is using an energy efficiency grant to provide commercial retrofits that will allow a local produce distribution company to dramatically reduce its energy costs and add dozens of new workers.

How Energy Efficiency is Adding Jobs in St. Paul, Minnesota

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hannigan, Jim; Coleman, Chris; Oliver, LeAnn

2011-01-01

Saint Paul, Minnesota is using an energy efficiency grant to provide commercial retrofits that will allow a local produce distribution company to dramatically reduce its energy costs and add dozens of new workers.

Improved flywheel materials :

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boyle, Timothy J.; Bell, Nelson S; Ehlen, Mark Andrew

As alternative energy generating devices (i.e., solar, wind, etc) are added onto the electrical energy grid (AC grid), irregularities in the available electricity due to natural occurrences (i.e., clouds reducing solar input or wind burst increasing wind powered turbines) will be dramatically increased. Due to their almost instantaneous response, modern flywheel-based energy storage devices can act a mechanical mechanism to regulate the AC grid; however, improved spin speeds will be required to meet the necessary energy levels to balance these green energy variances. Focusing on composite flywheels, we have investigated methods for improving the spin speeds based on materials needs.more » The so-called composite flywheels are composed of carbon fiber (C-fiber), glass fiber, and a glue (resin) to hold them together. For this effort, we have focused on the addition of fillers to the resin in order to improve its properties. Based on the high loads required for standard meso-sized fillers, this project investigated the utility of ceramic nanofillers since they can be added at very low load levels due to their high surface area. The impact that TiO2 nanowires had on the final strength of the flywheel material was determined by a three-point-bend test. The results of the introduction of nanomaterials demonstrated an increase in strength of the flywheels C-fiber-resin moiety, with an upper limit of a 30% increase being reported. An analysis of the economic impact concerning the utilization of the nanowires was undertaken and after accounting for new-technology and additional production costs, return on improved-nanocomposite investment was approximated at 4-6% per year over the 20-year expected service life. Further, it was determined based on the 30% improvement in strength, this change may enable a 20-30% reduction in flywheel energy storage cost ($/kW-h).« less

Dramatically Improve How and Where Academic Content Is Taught

ERIC Educational Resources Information Center

Hyslop, Alisha

2007-01-01

The fourth recommendation in ACTE's high school reform position statement is to dramatically improve how and where academic content is taught. Even as advanced academic course-taking and high school graduation requirements have increased, student achievement on national benchmarks has remained flat, and college remediation rates continue to…

Dramatic Developments in the Neurosciences Challenge Educators.

ERIC Educational Resources Information Center

Sylwester, Robert

1986-01-01

Recent dramatic developments in brain research and technology suggest that a comprehensive understanding of how the human brain works may soon be within reach. Just as the ability of the medical profession to treat patients improved dramatically with the advent of effective research skills and technology concerning the structure, biochemistry, and…

Low-energy hydraulic fracturing wastewater treatment via AC powered electrocoagulation with biochar.

PubMed

Lobo, Fernanda Leite; Wang, Heming; Huggins, Tyler; Rosenblum, James; Linden, Karl G; Ren, Zhiyong Jason

2016-05-15

Produced and flowback waters are the largest byproducts associated with unconventional oil and gas exploration and production. Sustainable and low cost technologies are needed to treat and reuse this wastewater to avoid the environmental problems associated with current management practices (i.e., deep well injection). This study presents a new process to integrate AC-powered electrocoagulation (EC) with granular biochar to dramatically reduce energy use and electrode passivation while achieving high treatment efficiency. Results show achieving a 99% turbidity and TSS removal for the AC-EC-biochar system only used 0.079 kWh/m(3) or 0.15 kWh/kg TSS, which is 70% lower than traditional DC-EC systems and orders of magnitude lower than previous studies. The amount of biochar added positively correlates with energy saving, and further studies are needed to improve organic carbon and salt removal through system integration. Copyright © 2016 Elsevier B.V. All rights reserved.

Thermal Management and Reliability of Power Electronics and Electric Machines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narumanchi, Sreekant

2016-09-19

Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil - by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, andmore » in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines are presented.« less

Techno-economic feasibility and life cycle assessment of dairy effluent to renewable diesel via hydrothermal liquefaction.

PubMed

Summers, Hailey M; Ledbetter, Rhesa N; McCurdy, Alex T; Morgan, Michael R; Seefeldt, Lance C; Jena, Umakanta; Hoekman, S Kent; Quinn, Jason C

2015-11-01

The economic feasibility and environmental impact is investigated for the conversion of agricultural waste, delactosed whey permeate, through yeast fermentation to a renewable diesel via hydrothermal liquefaction. Process feasibility was demonstrated at laboratory-scale with data leveraged to validate systems models used to perform industrial-scale economic and environmental impact analyses. Results show a minimum fuel selling price of $4.78 per gallon of renewable diesel, a net energy ratio of 0.81, and greenhouse gas emissions of 30.0g-CO2-eqMJ(-1). High production costs and greenhouse gas emissions can be attributed to operational temperatures and durations of both fermentation and hydrothermal liquefaction. However, high lipid yields of the yeast counter these operational demands, resulting in a favorable net energy ratio. Results are presented on the optimization of the process based on economy of scale and a sensitivity analysis highlights improvements in conversion efficiency, yeast biomass productivity and hydrotreating efficiency can dramatically improve commercial feasibility. Copyright © 2015 Elsevier Ltd. All rights reserved.

Arene-Inserted Extended Germa[n]pericyclynes: Synthesis, Structure, and Phosphorescence Properties.

PubMed

Tanimoto, Hiroki; Mori, Junta; Ito, Shunichiro; Nishiyama, Yasuhiro; Morimoto, Tsumoru; Tanaka, Kazuo; Chujo, Yoshiki; Kakiuchi, Kiyomi

2017-07-26

This report describes the synthesis and characterization of arene-inserted extended (ArEx) germa[n]pericyclynes composed of germanium and 1,4-diethynylbenzene units. These novel cyclic germanium-π unit materials were synthesized with diethynylbenzene and germanium dichloride. X-ray crystallographic analysis revealed their structures, and the planar conformation of ArEx germa[4]pericyclyne along with the regular aromatic rings. UV/Vis absorption spectra and fluorescence emission spectra showed considerably unique and highly improved character compared to previously reported germa[n]pericyclynes. Even in the absence of transition metal components, phosphorescence emissions were observed, and the emission lifetimes were dramatically improved. ArEx germa[n]pericyclynes showed high photoluminescence quantum yields, whereas low photoluminescence quantum yields were observed for acyclic compounds. Density functional theory calculations show delocalized orbitals between skipped alkyne units through a germanium tether, and an increase in the HOMO energy level, leading to a small HOMO-LUMO energy gap. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narumanchi, Sreekant

Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil - by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, andmore » in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines are presented.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narumanchi, Sreekant

Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil -- by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, andmore » in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines will be presented.« less

Monolayer graphene-insulator-semiconductor emitter for large-area electron lithography

NASA Astrophysics Data System (ADS)

Kirley, Matthew P.; Aloui, Tanouir; Glass, Jeffrey T.

2017-06-01

The rapid adoption of nanotechnology in fields as varied as semiconductors, energy, and medicine requires the continual improvement of nanopatterning tools. Lithography is central to this evolving nanotechnology landscape, but current production systems are subject to high costs, low throughput, or low resolution. Herein, we present a solution to these problems with the use of monolayer graphene in a graphene-insulator-semiconductor (GIS) electron emitter device for large-area electron lithography. Our GIS device displayed high emission efficiency (up to 13%) and transferred large patterns (500 × 500 μm) with high fidelity (<50% spread). The performance of our device demonstrates a feasible path to dramatic improvements in lithographic patterning systems, enabling continued progress in existing industries and opening opportunities in nanomanufacturing.

Influence of computational fluid dynamics on experimental aerospace facilities: A fifteen year projection

NASA Technical Reports Server (NTRS)

1983-01-01

An assessment was made of the impact of developments in computational fluid dynamics (CFD) on the traditional role of aerospace ground test facilities over the next fifteen years. With improvements in CFD and more powerful scientific computers projected over this period it is expected to have the capability to compute the flow over a complete aircraft at a unit cost three orders of magnitude lower than presently possible. Over the same period improvements in ground test facilities will progress by application of computational techniques including CFD to data acquisition, facility operational efficiency, and simulation of the light envelope; however, no dramatic change in unit cost is expected as greater efficiency will be countered by higher energy and labor costs.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, Prashant; Harbola, Manoj K.; Johnson, Duane D.

Here, this work constitutes a comprehensive and improved account of electronic-structure and mechanical properties of silicon-nitride (more » $${\\rm Si}_{3}$$ $${\\rm N}_{4}$$ ) polymorphs via van Leeuwen and Baerends (LB) exchange-corrected local density approximation (LDA) that enforces the exact exchange potential asymptotic behavior. The calculated lattice constant, bulk modulus, and electronic band structure of $${\\rm Si}_{3}$$ $${\\rm N}_{4}$$ polymorphs are in good agreement with experimental results. We also show that, for a single electron in a hydrogen atom, spherical well, or harmonic oscillator, the LB-corrected LDA reduces the (self-interaction) error to exact total energy to ~10%, a factor of three to four lower than standard LDA, due to a dramatically improved representation of the exchange-potential.« less

Geothermal Energy: Tapping the Potential

ERIC Educational Resources Information Center

Johnson, Bill

2008-01-01

Ground source geothermal energy enables one to tap into the earth's stored renewable energy for heating and cooling facilities. Proper application of ground-source geothermal technology can have a dramatic impact on the efficiency and financial performance of building energy utilization (30%+). At the same time, using this alternative energy…

Sustainable and Renewable Energy Resources — Alternative Forms of Energy

NASA Astrophysics Data System (ADS)

Rao, M. C.

In order to move towards a sustainable existence in our critically energy dependent society there is a continuing need to adopt environmentally sustainable methods for energy production, storage and conversion. A fuel cell is an energy conversion device that generates electricity and heat by electrochemically combining a gaseous fuel and an oxidant gas through electrodes and across an ion conducting electrolyte. The use of fuel cells in both stationary and mobile power applications can offer significant advantages for the sustainable conversion of energy. Currently the cost of fuel cell systems is greater than that of similar, already available products, mainly because of small scale production and the lack of economies of scale. The best fuel for fuel cells is hydrogen and another barrier is fuel flexibility. Benefits arising from the use of fuel cells include efficiency and reliability, as well as economy, unique operating characteristics and planning flexibility and future development potential. By integrating the application of fuel cells, in series with renewable energy storage and production methods, sustainable energy requirements may be realized. As fuel cell application increases and improved fuel storage methods and handlings are developed, it is expected that the costs associated with fuel cell systems will fall dramatically in the future.

Solar fuels production by artificial photosynthesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ager, Joel W., E-mail: JWAger@lbl.gov; Lee, Min-Hyung; Javey, Ali

2013-12-10

A practical method to use sunlight to generate storable chemical energy could dramatically change the landscape of global energy generation. One of the fundamental requirements of such an “artificial photosynthesis” scheme is a light capture and conversion approach capable of generating the required chemical potentials (e.g. >1.23 V for splitting water into H{sub 2} and O{sub 2}). An approach based on inorganic light absorbers coupled directly to oxidation and reduction catalysts is being developed in the Joint Center for Artificial Photosynthesis (JCAP). P-type III-V semiconductors with a high surface area can be used as high current density photocathodes. The longevitymore » under operation of these photocathodes can be improved by the use of conformal metal oxides deposited by atomic layer deposition.« less

Powering your car with sun light

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cosgrove, Daniel; Brown, Nicole; Kiemle, Sarah

Representing the Center for Lignocellulose Structure and Formation (CLSF), this document is one of the entries in the Ten Hundred and One Word Challenge and was awarded "Overall Winner." 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 CLSF is to dramatically increase ourmore » fundamental knowledge of the formation and physical interactions of bio-polymer networks in plant cell walls to provide a basis for improved methods for converting biomass into fuels.« less

Development of pixellated Ir-TESs

NASA Astrophysics Data System (ADS)

Zen, Nobuyuki; Takahashi, Hiroyuki; Kunieda, Yuichi; Damayanthi, Rathnayaka M. T.; Mori, Fumiakira; Fujita, Kaoru; Nakazawa, Masaharu; Fukuda, Daiji; Ohkubo, Masataka

2006-04-01

We have been developing Ir-based pixellated superconducting transition edge sensors (TESs). In the area of material or astronomical applications, the sensor with few eV energy resolution and over 1000 pixels imaging property is desired. In order to achieve this goal, we have been analyzing signals from pixellated TESs. In the case of a 20 pixel array of Ir-TESs, with 45 μm×45 μm pixel sizes, the incident X-ray signals have been classified into 16 groups. We have applied numerical signal analysis. On the one hand, the energy resolution of our pixellated TES is strongly degraded. However, using pulse shape analysis, we can dramatically improve the resolution. Thus, we consider that the pulse signal analysis will lead this device to be used as a practical photon incident position identifying TES.

Dihydrocapsiate improved age-associated impairments in mice by increasing energy expenditure.

PubMed

Ohyama, Kana; Suzuki, Katsuya

2017-11-01

Metabolic dysfunction is associated with aging and results in age-associated chronic diseases, including type 2 diabetes mellitus, cardiovascular disease, and stroke. Hence, there has been a focus on increasing energy expenditure in aged populations to protect them from age-associated diseases. Dihydrocapsiate (DCT) is a compound that belongs to the capsinoid family. Capsinoids are capsaicin analogs that are found in nonpungent peppers and increase whole body energy expenditure. However, their effect on energy expenditure has been reported only in young populations, and to date the effectiveness of DCT in increasing energy expenditure in aged populations has not been investigated. In this study, we investigated whether DCT supplementation in aged mice improves age-associated impairments. We obtained 5-wk-old and 1-yr-old male C57BL/6J mice and randomly assigned the aged mice to two groups, resulting in a total of three groups: 1 ) young mice, 2 ) old mice, and 3 ) old mice supplemented with 0.3% DCT. After 12 wk of supplementation, blood and tissue samples were collected and analyzed. DCT significantly suppressed age-associated fat accumulation, adipocyte hypertrophy, and liver steatosis. In addition, the DCT treatment dramatically suppressed age-associated increases in hepatic inflammation, immune cell infiltration, and oxidative stress. DCT exerted these suppression effects by increasing energy expenditure linked to upregulation of both the oxidative phosphorylation gene program and fatty acid oxidation in skeletal muscle. These results indicate that DCT efficiently improves age-associated impairments, including liver steatosis and inflammation, in part by increasing energy expenditure via activation of the fat oxidation pathway in skeletal muscle. Copyright © 2017 the American Physiological Society.

Exploiting Universality in Atoms with Large Scattering Lengths

DOE Office of Scientific and Technical Information (OSTI.GOV)

Braaten, Eric

2012-05-31

The focus of this research project was atoms with scattering lengths that are large compared to the range of their interactions and which therefore exhibit universal behavior at sufficiently low energies. Recent dramatic advances in cooling atoms and in manipulating their scattering lengths have made this phenomenon of practical importance for controlling ultracold atoms and molecules. This research project was aimed at developing a systematically improvable method for calculating few-body observables for atoms with large scattering lengths starting from the universal results as a first approximation. Significant progress towards this goal was made during the five years of the project.

Brain Tumors and Fatigue

MedlinePlus

... tiredness. You may experience a profound lack of energy that can come on suddenly and bring dramatic ... to manage the severity. Respect the Fatigue The energy you’re accustomed to having has been transferred ...

Toyota's tips drive dramatic ED improvements.

PubMed

2002-11-01

The Toyota Motor Corp.'s key concepts of allowing workers to make changes, putting the customer first, and reducing waste can have a dramatic impact when implemented in emergency departments. Staff should be empowered to make changes to improve quality. A chain of events should be set in motion for each customer request. Identify and eliminate roadblocks that cause delays.

Ionization energies of aqueous nucleic acids: photoelectron spectroscopy of pyrimidine nucleosides and ab initio calculations.

PubMed

Slavícek, Petr; Winter, Bernd; Faubel, Manfred; Bradforth, Stephen E; Jungwirth, Pavel

2009-05-13

Vertical ionization energies of the nucleosides cytidine and deoxythymidine in water, the lowest ones amounting in both cases to 8.3 eV, are obtained from photoelectron spectroscopy measurements in aqueous microjets. Ab initio calculations employing a nonequilibrium polarizable continuum model quantitatively reproduce the experimental spectra and provide molecular interpretation of the individual peaks of the photoelectron spectrum, showing also that lowest ionization originates from the base. Comparison of calculated vertical ionization potentials of pyrimidine bases, nucleosides, and nucleotides in water and in the gas phase underlines the dramatic effect of bulk hydration on the electronic structure. In the gas phase, the presence of sugar and, in particular, of phosphate has a strong effect on the energetics of ionization of the base. Upon bulk hydration, the ionization potential of the base in contrast becomes rather insensitive to the presence of the sugar and phosphate, which indicates a remarkable screening ability of the aqueous solvent. Accurate aqueous-phase vertical ionization potentials provide a significant improvement to the corrected gas-phase values used in the literature and represent important information in assessing the threshold energies for photooxidation and oxidation free energies of solvent-exposed DNA components. Likewise, such energetic data should allow improved assessment of delocalization and charge-hopping mechanisms in DNA ionized by radiation.

Final Scientific/Technical Report for Low Cost, High Capacity Non- Intercalation Chemistry Automotive Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berdichevsky, Gene

Commercial Li-ion batteries typically use Ni- and Co-based intercalation cathodes. As the demand for improved performance from batteries increases, these cathode materials will no longer be able to provide the desired energy storage characteristics since they are currently approaching their theoretical limits. Conversion cathode materials are prime candidates for improvement of Li-ion batteries. On both a volumetric and gravimetric basis they have higher theoretical capacity than intercalation cathode materials. Metal fluoride (MFx) cathodes offer higher specific energy density and dramatically higher volumetric energy density. Challenges associated with metal fluoride cathodes were addressed through nanostructured material design and synthesis. A majormore » goal of this project was to develop and demonstrate Li-ion cells based on Si-comprising anodes and metal fluoride (MFx) comprising cathodes. Pairing the high-capacity MFx cathode with a high-capacity anode, such as an alloying Si anode, allows for the highest possible energy density on a cell level. After facing and overcoming multiple material synthesis and electrochemical instability challenges, we succeeded in fabrication of MFx half cells with cycle stability in excess of 500 cycles (to 20% or smaller degradation) and full cells with MFx-based cathodes and Si-based anodes with cycle stability in excess of 200 cycles (to 20% or smaller degradation).« less

The legacy of fossil fuels.

PubMed

Armaroli, Nicola; Balzani, Vincenzo

2011-03-01

Currently, over 80% of the energy used by mankind comes from fossil fuels. Harnessing coal, oil and gas, the energy resources contained in the store of our spaceship, Earth, has prompted a dramatic expansion in energy use and a substantial improvement in the quality of life of billions of individuals in some regions of the world. Powering our civilization with fossil fuels has been very convenient, but now we know that it entails severe consequences. We treat fossil fuels as a resource that anyone anywhere can extract and use in any fashion, and Earth's atmosphere, soil and oceans as a dump for their waste products, including more than 30 Gt/y of carbon dioxide. At present, environmental legacy rather than consistence of exploitable reserves, is the most dramatic problem posed by the relentless increase of fossil fuel global demand. Harmful effects on the environment and human health, usually not incorporated into the pricing of fossil fuels, include immediate and short-term impacts related to their discovery, extraction, transportation, distribution, and burning as well as climate change that are spread over time to future generations or over space to the entire planet. In this essay, several aspects of the fossil fuel legacy are discussed, such as alteration of the carbon cycle, carbon dioxide rise and its measurement, greenhouse effect, anthropogenic climate change, air pollution and human health, geoengineering proposals, land and water degradation, economic problems, indirect effects on the society, and the urgent need of regulatory efforts and related actions to promote a gradual transition out of the fossil fuel era. While manufacturing sustainable solar fuels appears to be a longer-time perspective, alternatives energy sources already exist that have the potential to replace fossil fuels as feedstocks for electricity production. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Measurement of the 240Pu/ 239Pu mass ratio using a transition-edge-sensor microcalorimeter for total decay energy spectroscopy

DOE PAGES

Hoover, Andrew S.; Bond, Evelyn M.; Croce, Mark P.; ...

2015-02-27

In this study, we have developed a new category of sensor for measurement of the 240Pu/ 239Pu mass ratio from aqueous solution samples with advantages over existing methods. Aqueous solution plutonium samples were evaporated and encapsulated inside of a gold foil absorber, and a superconducting transition-edge-sensor microcalorimeter detector was used to measure the total reaction energy (Q-value) of nuclear decays via heat generated when the energy is thermalized. Since all of the decay energy is contained in the absorber, we measure a single spectral peak for each isotope, resulting in a simple spectral analysis problem with minimal peak overlap. Wemore » found that mechanical kneading of the absorber dramatically improves spectral quality by reducing the size of radioactive inclusions within the absorber to scales below 50 nm such that decay products primarily interact with atoms of the host material. Due to the low noise performance of the microcalorimeter detector, energy resolution values of 1 keV fwhm (full width at half-maximum) at 5.5 MeV have been achieved, an order of magnitude improvement over α-spectroscopy with conventional silicon detectors. We measured the 240Pu/ 239Pu mass ratio of two samples and confirmed the results by comparison to mass spectrometry values. These results have implications for future measurements of trace samples of nuclear material.« less

simuwatt - A Tablet Based Electronic Auditing Tool

DOE Office of Scientific and Technical Information (OSTI.GOV)

Macumber, Daniel; Parker, Andrew; Lisell, Lars

2014-05-08

'simuwatt Energy Auditor' (TM) is a new tablet-based electronic auditing tool that is designed to dramatically reduce the time and cost to perform investment-grade audits and improve quality and consistency. The tool uses the U.S. Department of Energy's OpenStudio modeling platform and integrated Building Component Library to automate modeling and analysis. simuwatt's software-guided workflow helps users gather required data, and provides the data in a standard electronic format that is automatically converted to a baseline OpenStudio model for energy analysis. The baseline energy model is calibrated against actual monthly energy use to ASHRAE Standard 14 guidelines. Energy conservation measures frommore » the Building Component Library are then evaluated using OpenStudio's parametric analysis capability. Automated reporting creates audit documents that describe recommended packages of energy conservation measures. The development of this tool was partially funded by the U.S. Department of Defense's Environmental Security Technology Certification Program. As part of this program, the tool is being tested at 13 buildings on 5 Department of Defense sites across the United States. Results of the first simuwatt audit tool demonstration are presented in this paper.« less

Improving Survival and Promoting Respiratory Motor Function After Cervical Spinal Cord Injury

DTIC Science & Technology

2017-09-01

ventilator in order to survive. Use of the ventilator severely limits the quality of life of those injured and dramatically increases the demand for health...care for cervical SCI patients so as to lead to an improved quality of life , better-quality health care management, and improved functional outcomes...mechanical ventilator in order to survive. Use of the ventilator severely limits the quality of life of those injured and dramatically increases the

The External Performance Appraisal of China Energy Regulation: An Empirical Study Using a TOPSIS Method Based on Entropy Weight and Mahalanobis Distance.

PubMed

Wang, Zheng-Xin; Li, Dan-Dan; Zheng, Hong-Hao

2018-01-30

In China's industrialization process, the effective regulation of energy and environment can promote the positive externality of energy consumption while reducing negative externality, which is an important means for realizing the sustainable development of an economic society. The study puts forward an improved technique for order preference by similarity to an ideal solution based on entropy weight and Mahalanobis distance (briefly referred as E-M-TOPSIS). The performance of the approach was verified to be satisfactory. By separately using traditional and improved TOPSIS methods, the study carried out the empirical appraisals on the external performance of China's energy regulation during 1999~2015. The results show that the correlation between the performance indexes causes the significant difference between the appraisal results of E-M-TOPSIS and traditional TOPSIS. The E-M-TOPSIS takes the correlation between indexes into account and generally softens the closeness degree compared with traditional TOPSIS. Moreover, it makes the relative closeness degree fluctuate within a small-amplitude. The results conform to the practical condition of China's energy regulation and therefore the E-M-TOPSIS is favorably applicable for the external performance appraisal of energy regulation. Additionally, the external economic performance and social responsibility performance (including environmental and energy safety performances) based on the E-M-TOPSIS exhibit significantly different fluctuation trends. The external economic performance dramatically fluctuates with a larger fluctuation amplitude, while the social responsibility performance exhibits a relatively stable interval fluctuation. This indicates that compared to the social responsibility performance, the fluctuation of external economic performance is more sensitive to energy regulation.

Effects of copper amine treatments on mechanical, biological and surface/interphase properties of poly (vinyl chloride)/wood composites

NASA Astrophysics Data System (ADS)

Jiang, Haihong

2005-11-01

The copper ethanolamine (CuEA) complex was used as a wood surface modifier and a coupling agent for wood-PVC composites. Mechanical properties of composites, such as unnotched impact strength, flexural strength and flexural toughness, were significantly increased, and fungal decay weight loss was dramatically decreased by wood surface copper amine treatments. It is evident that copper amine was a very effective coupling agent and decay inhibitor for PVC/wood flour composites, especially in high wood flour loading level. A DSC study showed that the heat capacity differences (DeltaCp) of composites before and after PVC glass transition were reduced by adding wood particles. A DMA study revealed that the movements of PVC chain segments during glass transition were limited and obstructed by the presence of wood molecule chains. This restriction effect became stronger by increasing wood flour content and by using Cu-treated wood flour. Wood flour particles acted as "physical cross-linking points" inside the PVC matrix, resulting in the absence of the rubbery plateau of PVC and higher E', E'' above Tg, and smaller tan delta peaks. Enhanced mechanical performances were attributed to the improved wetting condition between PVC melts and wood surfaces, and the formation of a stronger interphase strengthened by chemical interactions between Cu-treated wood flour and the PVC matrix. Contact angles of PVC solution drops on Cu-treated wood surfaces were decreased dramatically compared to those on the untreated surfaces. Acid-base (polar), gammaAB, electron-acceptor (acid) (gamma +), electron-donor (base) (gamma-) surface energy components and the total surface energies increased after wood surface Cu-treatments, indicating a strong tendency toward acid-base or polar interactions. Improved interphase and interfacial adhesion were further confirmed by measuring interfacial shear strength between wood and the PVC matrix.

Modification of earth-satellite orbits using medium-energy pulsed lasers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phipps, C.R.

1992-01-01

Laser Impulse Space Propulsion (LISP) has become an attractive concept, due to recent advances in gas laser technology, high-speed segmented mirrors and improved coeffici-ents for momentum coupling to targets in pulsed laser ablation. There are numerous specialized applications of the basic concept to space science-ranging from far-future and high capital cost to the immediate and inexpensive, such as: LEO-LISP (launch of massive objects into low-Earth-Orbit at dramatically improved cost-per-kg relative to present practice); LEGO-LISP (LEO to geosynchronous transfers); LO-LISP) (periodic re-boost of decaying LEO orbits); and LISK (geosynchronous satellite station-keeping). It is unlikely that one type of laser will bemore » best for all scenarios. In this paper, we will focus on the last two applications.« less

Modification of earth-satellite orbits using medium-energy pulsed lasers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phipps, C.R.

1992-10-01

Laser Impulse Space Propulsion (LISP) has become an attractive concept, due to recent advances in gas laser technology, high-speed segmented mirrors and improved coeffici-ents for momentum coupling to targets in pulsed laser ablation. There are numerous specialized applications of the basic concept to space science-ranging from far-future and high capital cost to the immediate and inexpensive, such as: LEO-LISP (launch of massive objects into low-Earth-Orbit at dramatically improved cost-per-kg relative to present practice); LEGO-LISP (LEO to geosynchronous transfers); LO-LISP) (periodic re-boost of decaying LEO orbits); and LISK (geosynchronous satellite station-keeping). It is unlikely that one type of laser will bemore » best for all scenarios. In this paper, we will focus on the last two applications.« less

White butterflies as solar photovoltaic concentrators.

PubMed

Shanks, Katie; Senthilarasu, S; Ffrench-Constant, Richard H; Mallick, Tapas K

2015-07-31

Man's harvesting of photovoltaic energy requires the deployment of extensive arrays of solar panels. To improve both the gathering of thermal and photovoltaic energy from the sun we have examined the concept of biomimicry in white butterflies of the family Pieridae. We tested the hypothesis that the V-shaped posture of basking white butterflies mimics the V-trough concentrator which is designed to increase solar input to photovoltaic cells. These solar concentrators improve harvesting efficiency but are both heavy and bulky, severely limiting their deployment. Here, we show that the attachment of butterfly wings to a solar cell increases its output power by 42.3%, proving that the wings are indeed highly reflective. Importantly, and relative to current concentrators, the wings improve the power to weight ratio of the overall structure 17-fold, vastly expanding their potential application. Moreover, a single mono-layer of scale cells removed from the butterflies' wings maintained this high reflectivity showing that a single layer of scale cell-like structures can also form a useful coating. As predicted, the wings increased the temperature of the butterflies' thorax dramatically, showing that the V-shaped basking posture of white butterflies has indeed evolved to increase the temperature of their flight muscles prior to take-off.

White butterflies as solar photovoltaic concentrators

NASA Astrophysics Data System (ADS)

Shanks, Katie; Senthilarasu, S.; Ffrench-Constant, Richard H.; Mallick, Tapas K.

2015-07-01

Man’s harvesting of photovoltaic energy requires the deployment of extensive arrays of solar panels. To improve both the gathering of thermal and photovoltaic energy from the sun we have examined the concept of biomimicry in white butterflies of the family Pieridae. We tested the hypothesis that the V-shaped posture of basking white butterflies mimics the V-trough concentrator which is designed to increase solar input to photovoltaic cells. These solar concentrators improve harvesting efficiency but are both heavy and bulky, severely limiting their deployment. Here, we show that the attachment of butterfly wings to a solar cell increases its output power by 42.3%, proving that the wings are indeed highly reflective. Importantly, and relative to current concentrators, the wings improve the power to weight ratio of the overall structure 17-fold, vastly expanding their potential application. Moreover, a single mono-layer of scale cells removed from the butterflies’ wings maintained this high reflectivity showing that a single layer of scale cell-like structures can also form a useful coating. As predicted, the wings increased the temperature of the butterflies’ thorax dramatically, showing that the V-shaped basking posture of white butterflies has indeed evolved to increase the temperature of their flight muscles prior to take-off.

Prospects for GLAST

NASA Technical Reports Server (NTRS)

McEnery, Julie

2006-01-01

The Gamma-ray Large Area Space Telescope (GLAST), scheduled for launch in late 007, is a satellite based observatory to study the high energy gamma-ray sky. There are two instruments on GLAST: the Large Area Telescope (LAT) which provides coverage from 20 MeV to over 300 GeV, and the GLAST Burst Monitor (GBM) which provides supportive observations of transients from 8 keV to 30 MeV. GLAST will provide well beyond those achieved by the highly successful EGRET instrument on the Compton Gamma-Ray Observatory, with dramatic improvements in sensitivity, angular resolution and energy range. The very large field of view will make it possible to observe approx. 20% of the sky at any instant, and the entire sky on timescale of a few hours. This talk includes a description of the instruments, the opportunities for guest investigators, and the mission status.

Consortium for Algal Biofuel Commercialization (CAB-COMM) Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mayfield, Stephen P.

The Consortium for Algal Biofuel Commercialization (CAB-Comm) was established in 2010 to conduct research to enable commercial viability of alternative liquid fuels produced from algal biomass. The main objective of CAB-Comm was to dramatically improve the viability of algae as a source of liquid fuels to meet US energy needs, by addressing several significant barriers to economic viability. To achieve this goal, CAB-Comm took a diverse set of approaches on three key aspects of the algal biofuels value chain: crop protection; nutrient utilization and recycling; and the development of genetic tools. These projects have been undertaken as collaboration between sixmore » academic institutions and two industrial partners: University of California, San Diego; Scripps Institution of Oceanography; University of Nebraska, Lincoln; Rutgers University; University of California, Davis; Johns Hopkins University; Sapphire Energy; and Life Technologies.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhen Li; Rishika Haynes; Eugene Sato

Microbial fuel cells (MFCs) convert chemical energy to electrical energy via bioelectrochemical reactions mediated by microorganisms. We investigated the diversity of the microbial community in an air cathode single chamber MFC that utilized potato-process wastewater as substrate. Terminal Restriction Fragment Length Polymorphism (T-RFLP) results indicated that the bacterial communities on the anode, cathode, control electrode, and MFC bulk fluid were similar, but differed dramatically from that of the anaerobic domestic sludge and potato wastewater inoculum. The 16S rDNA sequencing results showed that microbial species detected on the anode were predominantly within the phyla of Proteobacteria, Firmicutes, and Bacteroidetes. Fluorescent microscopymore » results indicated that there was a clear enhancement of biofilm formation on the anode. Results of this study could help improve understanding of the complexity of microbial communities and optimize the microbial composition for generating electricity by MFCs that utilize potato wastewater.« less

Redshift drift constraints on holographic dark energy

NASA Astrophysics Data System (ADS)

He, Dong-Ze; Zhang, Jing-Fei; Zhang, Xin

2017-03-01

The Sandage-Loeb (SL) test is a promising method for probing dark energy because it measures the redshift drift in the spectra of Lyman- α forest of distant quasars, covering the "redshift desert" of 2 ≲ z ≲ 5, which is not covered by existing cosmological observations. Therefore, it could provide an important supplement to current cosmological observations. In this paper, we explore the impact of SL test on the precision of cosmological constraints for two typical holographic dark energy models, i.e., the original holographic dark energy (HDE) model and the Ricci holographic dark energy (RDE) model. To avoid data inconsistency, we use the best-fit models based on current combined observational data as the fiducial models to simulate 30 mock SL test data. The results show that SL test can effectively break the existing strong degeneracy between the present-day matter density Ωm0 and the Hubble constant H 0 in other cosmological observations. For the considered two typical dark energy models, not only can a 30-year observation of SL test improve the constraint precision of Ωm0 and h dramatically, but can also enhance the constraint precision of the model parameters c and α significantly.

AGN Science with AGIS

NASA Astrophysics Data System (ADS)

Coppi, Paolo

2009-05-01

AGIS, a proposed future gamma-ray telescope consisting of a square km array of 50 atmospheric Cherenkov telescopes, will provide a powerful new view of the high energy universe. The combination of its increased sensitivity (a factor 10 over current observatories), increased survey capabilities, and a low energy threshold (<30 GeV) that allows observations at energies not subject to absorption on extragalactic background light will result in a dramatic increase in the number of AGN accessible at high energies. The overall number of ``TeV blazar" AGN, those detected by current ground-based observatories, should increase by a factor 30 or more with a corresponding increase in the number of these that can be monitored at high statistical significance to test emission models rigorously. More excitingly, AGIS may also begin to pick up entirely new classes of AGN such as radio galaxies with X-ray emitting hotspots at large distances from the central engine, providing further insight into the outflows from AGN. The low AGIS threshold energy will also allow significant source overlap with objects detected by the recently launched Fermi gamma-ray space observatory at lower, GeV energies. AGIS will significantly improve on the localization and variability monitoring of the Fermi sources it sees.

NASA Fixed Wing Project: Green Technologies for Future Aircraft Generation

NASA Technical Reports Server (NTRS)

Del Rosario, Ruben; Koudelka, John M.; Wahls, Rich; Madavan, Nateri

2014-01-01

Commercial aviation relies almost entirely on subsonic fixed wing aircraft to constantly move people and goods from one place to another across the globe. While air travel is an effective means of transportation providing an unmatched combination of speed and range, future subsonic aircraft must improve substantially to meet efficiency and environmental targets.The NASA Fundamental Aeronautics Fixed Wing (FW) Project addresses the comprehensive challenge of enabling revolutionary energy efficiency improvements in subsonic transport aircraft combined with dramatic reductions in harmful emissions and perceived noise to facilitate sustained growth of the air transportation system. Advanced technologies and the development of unconventional aircraft systems offer the potential to achieve these improvements. Multidisciplinary advances are required in aerodynamic efficiency to reduce drag, structural efficiency to reduce aircraft empty weight, and propulsive and thermal efficiency to reduce thrust-specific energy consumption (TSEC) for overall system benefit. Additionally, advances are required to reduce perceived noise without adversely affecting drag, weight, or TSEC, and to reduce harmful emissions without adversely affecting energy efficiency or noise.The paper will highlight the Fixed Wing project vision of revolutionary systems and technologies needed to achieve these challenging goals. Specifically, the primary focus of the FW Project is on the N+3 generation; that is, vehicles that are three generations beyond the current state of the art, requiring mature technology solutions in the 2025-30 timeframe

Energy use and carbon footprints differ dramatically for diverse wastewater-derived carbonaceous substrates: An integrated exploration of biokinetics and life-cycle assessment.

PubMed

Li, Yanbo; Wang, Xu; Butler, David; Liu, Junxin; Qu, Jiuhui

2017-03-21

Energy neutrality and reduction of carbon emissions are significant challenges to the enhanced sustainability of wastewater treatment plants (WWTPs). Harvesting energy from wastewater carbonaceous substrates can offset energy demands and enable net power generation; yet, there is limited research about how carbonaceous substrates influence energy and carbon implications of WWTPs with integrated energy recovery at systems-level. Consequently, this research uses biokinetics modelling and life cycle assessment philology to explore this notion, by tracing and assessing the quantitative flows of energy embodied or captured, and by exploring the carbon footprint throughout an energy-intensive activated sludge process with integrated energy recovery facilities. The results indicate that energy use and carbon footprint per cubic meter of wastewater treated, varies markedly with the carbon substrate. Compared with systems driven with proteins, carbohydrates or other short-chain fatty acids, systems fed with acetic acid realized energy neutrality with maximal net gain of power from methane combustion (0.198 kWh) and incineration of residual biosolids (0.153 kWh); and also achieved a negative carbon footprint (72.6 g CO 2 ). The findings from this work help us to better understand and develop new technical schemes for improving the energy efficiency of WWTPs by repurposing the stream of carbon substrates across systems.

Polymer solar cells with enhanced open-circuit voltage and efficiency

NASA Astrophysics Data System (ADS)

Chen, Hsiang-Yu; Hou, Jianhui; Zhang, Shaoqing; Liang, Yongye; Yang, Guanwen; Yang, Yang; Yu, Luping; Wu, Yue; Li, Gang

2009-11-01

Following the development of the bulk heterojunction structure, recent years have seen a dramatic improvement in the efficiency of polymer solar cells. Maximizing the open-circuit voltage in a low-bandgap polymer is one of the critical factors towards enabling high-efficiency solar cells. Study of the relation between open-circuit voltage and the energy levels of the donor/acceptor in bulk heterojunction polymer solar cells has stimulated interest in modifying the open-circuit voltage by tuning the energy levels of polymers. Here, we show that the open-circuit voltage of polymer solar cells constructed based on the structure of a low-bandgap polymer, PBDTTT, can be tuned, step by step, using different functional groups, to achieve values as high as 0.76 V. This increased open-circuit voltage combined with a high short-circuit current density results in a polymer solar cell with a power conversion efficiency as high as 6.77%, as certified by the National Renewable Energy Laboratory.

Power technologies and the space future

NASA Technical Reports Server (NTRS)

Faymon, Karl A.; Fordyce, J. Stuart; Brandhorst, Henry W., Jr.

1991-01-01

Advancements in space power and energy technologies are critical to serve space development needs and help solve problems on Earth. The availability of low cost power and energy in space will be the hallmark of this advance. Space power will undergo a dramatic change for future space missions. The power systems which have served the U.S. space program so well in the past will not suffice for the missions of the future. This is especially true if the space commercialization is to become a reality. New technologies, and new and different space power architectures and topologies will replace the lower power, low-voltage systems of the past. Efficiencies will be markedly improved, specific powers will be greatly increased, and system lifetimes will be markedly extended. Space power technology is discussed - its past, its current status, and predictions about where it will go in the future. A key problem for power and energy is its cost of affordability. Power must be affordable or it will not serve future needs adequately. This aspect is also specifically addressed.

Sustainable IT and IT for Sustainability

NASA Astrophysics Data System (ADS)

Liu, Zhenhua

Energy and sustainability have become one of the most critical issues of our generation. While the abundant potential of renewable energy such as solar and wind provides a real opportunity for sustainability, their intermittency and uncertainty present a daunting operating challenge. This thesis aims to develop analytical models, deployable algorithms, and real systems to enable efficient integration of renewable energy into complex distributed systems with limited information. The first thrust of the thesis is to make IT systems more sustainable by facilitating the integration of renewable energy into these systems. IT represents the fastest growing sectors in energy usage and greenhouse gas pollution. Over the last decade there are dramatic improvements in the energy efficiency of IT systems, but the efficiency improvements do not necessarily lead to reduction in energy consumption because more servers are demanded. Further, little effort has been put in making IT more sustainable, and most of the improvements are from improved "engineering" rather than improved "algorithms". In contrast, my work focuses on developing algorithms with rigorous theoretical analysis that improve the sustainability of IT. In particular, this thesis seeks to exploit the flexibilities of cloud workloads both (i) in time by scheduling delay-tolerant workloads and (ii) in space by routing requests to geographically diverse data centers. These opportunities allow data centers to adaptively respond to renewable availability, varying cooling efficiency, and fluctuating energy prices, while still meeting performance requirements. The design of the enabling algorithms is however very challenging because of limited information, non-smooth objective functions and the need for distributed control. Novel distributed algorithms are developed with theoretically provable guarantees to enable the "follow the renewables" routing. Moving from theory to practice, I helped HP design and implement industry's first Net-zero Energy Data Center. The second thrust of this thesis is to use IT systems to improve the sustainability and efficiency of our energy infrastructure through data center demand response. The main challenges as we integrate more renewable sources to the existing power grid come from the fluctuation and unpredictability of renewable generation. Although energy storage and reserves can potentially solve the issues, they are very costly. One promising alternative is to make the cloud data centers demand responsive. The potential of such an approach is huge. To realize this potential, we need adaptive and distributed control of cloud data centers and new electricity market designs for distributed electricity resources. My work is progressing in both directions. In particular, I have designed online algorithms with theoretically guaranteed performance for data center operators to deal with uncertainties under popular demand response programs. Based on local control rules of customers, I have further designed new pricing schemes for demand response to align the interests of customers, utility companies, and the society to improve social welfare.

The synergistic effect in the Fe-Co bimetallic catalyst system for the growth of carbon nanotube forests

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hardeman, D.; Esconjauregui, S., E-mail: cse28@cam.ac.uk; Cartwright, R.

2015-01-28

We report the growth of multi-walled carbon nanotube forests employing an active-active bimetallic Fe-Co catalyst. Using this catalyst system, we observe a synergistic effect by which—in comparison to pure Fe or Co—the height of the forests increases significantly. The homogeneity in the as-grown nanotubes is also improved. By both energy dispersive spectroscopy and in-situ x-ray photoelectron spectroscopy, we show that the catalyst particles consist of Fe and Co, and this dramatically increases the growth rate of the tubes. Bimetallic catalysts are thus potentially useful for synthesising nanotube forests more efficiently.

Effect of enzymatic (thermostable α-amylase) treatment on the physicochemical and antioxidant properties of extruded rice incorporated with soybean flour.

PubMed

Xu, Enbo; Wu, Zhengzong; Pan, Xiaowei; Long, Jie; Wang, Fang; Xu, Xueming; Jin, Zhengyu; Jiao, Aiquan

2016-04-15

In order to determine the effect of enzymatic extrusion on the physicochemical and antioxidant properties of rice/soybean mixture, different mass ratios (100/0, 95/5, 85/15, 70/30, 50/50 and 25/75%, w/w) were treated with thermostable α-amylase. The reduced special mechanical energy and the enhanced product temperature were closely and regularly linked with the increase of soybean content. The bulk density and water solubility index increased, and the water absorption index and viscosities decreased remarkably after enzymatic extrusion, however, the modification caused by α-amylase were dramatically eliminated with the increase of soybean content to ∼50%. Moreover, the addition of enzyme exhibited an improvement of the total phenolic/flavonoid content (TPC/TFC) and antioxidant capacities compared to traditional extrusion. The TPC/TFC retention of extrudate (ratios of 85/15 and 70/30%) attained over 90%, but dramatically decreased (72.91 and 67.81%, respectively) with soybean added to 75%, probably due to the great reduction of starch substrate for enzymatic hydrolysis. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Nucleation and atomic layer reaction in nickel silicide for defect-engineered Si nanochannels.

PubMed

Tang, Wei; Picraux, S Tom; Huang, Jian Yu; Gusak, Andriy M; Tu, King-Ning; Dayeh, Shadi A

2013-06-12

At the nanoscale, defects can significantly impact phase transformation processes and change materials properties. The material nickel silicide has been the industry standard electrical contact of silicon microelectronics for decades and is a rich platform for scientific innovation at the conjunction of materials and electronics. Its formation in nanoscale silicon devices that employ high levels of strain, intentional, and unintentional twins or grain boundaries can be dramatically different from the commonly conceived bulk processes. Here, using in situ high-resolution transmission electron microscopy (HRTEM), we capture single events during heterogeneous nucleation and atomic layer reaction of nickel silicide at various crystalline boundaries in Si nanochannels for the first time. We show through systematic experiments and analytical modeling that unlike other typical face-centered cubic materials such as copper or silicon the twin defects in NiSi2 have high interfacial energies. We observe that these twin defects dramatically change the behavior of new phase nucleation and can have direct implications for ultrascaled devices that are prone to defects or may utilize them to improve device performance.

Advanced Li-Ion Hybrid Supercapacitors Based on 3D Graphene-Foam Composites.

PubMed

Liu, Wenwen; Li, Jingde; Feng, Kun; Sy, Abel; Liu, Yangshuai; Lim, Lucas; Lui, Gregory; Tjandra, Ricky; Rasenthiram, Lathankan; Chiu, Gordon; Yu, Aiping

2016-10-05

Li-ion hybrid supercapacitors (LIHSs) have recently attracted increasing attention as a new and promising energy storage device. However, it is still a great challenge to construct novel LIHSs with high-performance due to the majority of battery-type anodes retaining the sluggish kinetics of Li-ion storage and most capacitor-type cathodes with low specific capacitance. To solve this problem, 3D graphene-wrapped MoO 3 nanobelt foam with the unique porous network structure has been designed and prepared as anode material, which delivers high capacity, improved rate performance, and enhanced cycle stability. First-principles calculation reveals that the combination of graphene dramatically reduces the diffusion energy barrier of Li + adsorbed on the surface of MoO 3 nanobelt, thus improving its electrochemical performance. Furthermore, 3D graphene-wrapped polyaniline nanotube foam derived carbon is employed as a new type of capacitor-type cathode, demonstrating high specific capacitance, good rate performance, and long cycle stability. Benefiting from these two graphene foam-enhanced materials, the constructed LIHSs show a wide operating voltage range (3.8 V), a long stable cycle life (90% capacity retention after 3000 cycles), a high energy density (128.3 Wh·kg -1 ), and a high power density (13.5 kW·kg -1 ). These encouraging performances indicate that the obtained LIHSs may have promising prospect as next-generation energy-storage devices.

Parallel elastic elements improve energy efficiency on the STEPPR bipedal walking robot

DOE PAGES

Mazumdar, Anirban; Spencer, Steven J.; Hobart, Clinton; ...

2016-11-23

This study describes how parallel elastic elements can be used to reduce energy consumption in the electric motor driven, fully-actuated, STEPPR bipedal walking robot without compromising or significantly limiting locomotive behaviors. A physically motivated approach is used to illustrate how selectively-engaging springs for hip adduction and ankle flexion predict benefits for three different flat ground walking gaits: human walking, human-like robot walking and crouched robot walking. Based on locomotion data, springs are designed and substantial reductions in power consumption are demonstrated using a bench dynamometer. These lessons are then applied to STEPPR (Sandia Transmission-Efficient Prototype Promoting Research), a fully actuatedmore » bipedal robot designed to explore the impact of tailored joint mechanisms on walking efficiency. Featuring high-torque brushless DC motors, efficient low-ratio transmissions, and high fidelity torque control, STEPPR provides the ability to incorporate novel joint-level mechanisms without dramatically altering high level control. Unique parallel elastic designs are incorporated into STEPPR, and walking data shows that hip adduction and ankle flexion springs significantly reduce the required actuator energy at those joints for several gaits. These results suggest that parallel joint springs offer a promising means of supporting quasi-static joint torques due to body mass during walking, relieving motors of the need to support these torques and substantially improving locomotive energy efficiency.« less

Parallel elastic elements improve energy efficiency on the STEPPR bipedal walking robot

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mazumdar, Anirban; Spencer, Steven J.; Hobart, Clinton

This study describes how parallel elastic elements can be used to reduce energy consumption in the electric motor driven, fully-actuated, STEPPR bipedal walking robot without compromising or significantly limiting locomotive behaviors. A physically motivated approach is used to illustrate how selectively-engaging springs for hip adduction and ankle flexion predict benefits for three different flat ground walking gaits: human walking, human-like robot walking and crouched robot walking. Based on locomotion data, springs are designed and substantial reductions in power consumption are demonstrated using a bench dynamometer. These lessons are then applied to STEPPR (Sandia Transmission-Efficient Prototype Promoting Research), a fully actuatedmore » bipedal robot designed to explore the impact of tailored joint mechanisms on walking efficiency. Featuring high-torque brushless DC motors, efficient low-ratio transmissions, and high fidelity torque control, STEPPR provides the ability to incorporate novel joint-level mechanisms without dramatically altering high level control. Unique parallel elastic designs are incorporated into STEPPR, and walking data shows that hip adduction and ankle flexion springs significantly reduce the required actuator energy at those joints for several gaits. These results suggest that parallel joint springs offer a promising means of supporting quasi-static joint torques due to body mass during walking, relieving motors of the need to support these torques and substantially improving locomotive energy efficiency.« less

Lean, Mean and Green: An Affordable Net Zero School

ERIC Educational Resources Information Center

Stanfield, Kenneth

2010-01-01

From its conception, Richardsville Elementary was designed to be an affordable net zero facility. The design team explored numerous energy saving strategies to dramatically reduce energy consumption. By reducing energy use to 19.31 kBtus annually, the net zero goal could be realized through the implementation of a solar array capable of producing…

Respective effects of oxygen and energy substrate deprivation on beta cell viability.

PubMed

Lablanche, Sandrine; Cottet-Rousselle, Cécile; Argaud, Laurent; Laporte, Camille; Lamarche, Frédéric; Richard, Marie-Jeanne; Berney, Thierry; Benhamou, Pierre-Yves; Fontaine, Eric

2015-01-01

Deficit in oxygen and energetic substrates delivery is a key factor in islet loss during islet transplantation. Permeability transition pore (PTP) is a mitochondrial channel involved in cell death. We have studied the respective effects of oxygen and energy substrate deprivation on beta cell viability as well as the involvement of oxidative stress and PTP opening. Energy substrate deprivation for 1h followed by incubation in normal conditions led to a cyclosporin A (CsA)-sensitive-PTP-opening in INS-1 cells and human islets. Such a procedure dramatically decreased INS-1 cells viability except when transient removal of energy substrates was performed in anoxia, in the presence of antioxidant N-acetylcysteine (NAC) or when CsA or metformin inhibited PTP opening. Superoxide production increased during removal of energy substrates and increased again when normal energy substrates were restored. NAC, anoxia or metformin prevented the two phases of oxidative stress while CsA prevented the second one only. Hypoxia or anoxia alone did not induce oxidative stress, PTP opening or cell death. In conclusion, energy substrate deprivation leads to an oxidative stress followed by PTP opening, triggering beta cell death. Pharmacological prevention of PTP opening during islet transplantation may be a suitable option to improve islet survival and graft success. Copyright © 2015 Elsevier B.V. All rights reserved.

The External Performance Appraisal of China Energy Regulation: An Empirical Study Using a TOPSIS Method Based on Entropy Weight and Mahalanobis Distance

PubMed Central

Li, Dan-Dan; Zheng, Hong-Hao

2018-01-01

In China’s industrialization process, the effective regulation of energy and environment can promote the positive externality of energy consumption while reducing negative externality, which is an important means for realizing the sustainable development of an economic society. The study puts forward an improved technique for order preference by similarity to an ideal solution based on entropy weight and Mahalanobis distance (briefly referred as E-M-TOPSIS). The performance of the approach was verified to be satisfactory. By separately using traditional and improved TOPSIS methods, the study carried out the empirical appraisals on the external performance of China’s energy regulation during 1999~2015. The results show that the correlation between the performance indexes causes the significant difference between the appraisal results of E-M-TOPSIS and traditional TOPSIS. The E-M-TOPSIS takes the correlation between indexes into account and generally softens the closeness degree compared with traditional TOPSIS. Moreover, it makes the relative closeness degree fluctuate within a small-amplitude. The results conform to the practical condition of China’s energy regulation and therefore the E-M-TOPSIS is favorably applicable for the external performance appraisal of energy regulation. Additionally, the external economic performance and social responsibility performance (including environmental and energy safety performances) based on the E-M-TOPSIS exhibit significantly different fluctuation trends. The external economic performance dramatically fluctuates with a larger fluctuation amplitude, while the social responsibility performance exhibits a relatively stable interval fluctuation. This indicates that compared to the social responsibility performance, the fluctuation of external economic performance is more sensitive to energy regulation. PMID:29385781

Advanced technique for ultra-thin residue inspection with sub-10nm thickness using high-energy back-scattered electrons

NASA Astrophysics Data System (ADS)

Han, Jin-Hee

2018-03-01

Recently the aspect ratio of capacitor and via hole of memory semiconductor device has been dramatically increasing in order to store more information in a limited area. A small amount of remained residues after etch process on the bottom of the high aspect ratio structure can make a critical failure in device operation. Back-scattered electrons (BSE) are mainly used for inspecting the defect located at the bottom of the high aspect ratio structure or analyzing the overlay of the multi-layer structure because these electrons have a high linearity with the direction of emission and a high kinetic energy above 50eV. However, there is a limitation on that it cannot detect ultra-thin residue material having a thickness of several nanometers because the surface sensitivity is extremely low. We studied the characteristics of BSE spectra using Monte Carlo simulations for several cases which the high aspect ratio structures have extreme microscopic residues. Based on the assumption that most of the electrons emitted without energy loss are localized on the surface, we selected the detection energy window which has a range of 20eV below the maximum energy of the BSE. This window section is named as the high-energy BSE region. As a result of comparing the detection sensitivity of the conventional and the high-energy BSE detection mode, we found that the detection sensitivity for the residuals which have 2nm thickness is improved by more than 10 times in the high-energy BSE mode. This BSE technology is a new inspection method that can greatly be improved the inspection sensitivity for the ultra-thin residual material presented in the high aspect ratio structure, and its application will be expanded.

Better band gaps for wide-gap semiconductors from a locally corrected exchange-correlation potential that nearly eliminates self-interaction errors

DOE PAGES

Singh, Prashant; Harbola, Manoj K.; Johnson, Duane D.

2017-09-08

Here, this work constitutes a comprehensive and improved account of electronic-structure and mechanical properties of silicon-nitride (more » $${\\rm Si}_{3}$$ $${\\rm N}_{4}$$ ) polymorphs via van Leeuwen and Baerends (LB) exchange-corrected local density approximation (LDA) that enforces the exact exchange potential asymptotic behavior. The calculated lattice constant, bulk modulus, and electronic band structure of $${\\rm Si}_{3}$$ $${\\rm N}_{4}$$ polymorphs are in good agreement with experimental results. We also show that, for a single electron in a hydrogen atom, spherical well, or harmonic oscillator, the LB-corrected LDA reduces the (self-interaction) error to exact total energy to ~10%, a factor of three to four lower than standard LDA, due to a dramatically improved representation of the exchange-potential.« less

High Energy Electron Detectors on Sphinx

NASA Astrophysics Data System (ADS)

Thompson, J. R.; Porte, A.; Zucchini, F.; Calamy, H.; Auriel, G.; Coleman, P. L.; Bayol, F.; Lalle, B.; Krishnan, M.; Wilson, K.

2008-11-01

Z-pinch plasma radiation sources are used to dose test objects with K-shell (˜1-4keV) x-rays. The implosion physics can produce high energy electrons (> 50keV), which could distort interpretation of the soft x-ray effects. We describe the design and implementation of a diagnostic suite to characterize the electron environment of Al wire and Ar gas puff z-pinches on Sphinx. The design used ITS calculations to model detector response to both soft x-rays and electrons and help set upper bounds to the spurious electron flux. Strategies to discriminate between the known soft x-ray emission and the suspected electron flux will be discussed. H.Calamy et al, ``Use of microsecond current prepulse for dramatic improvements of wire array Z-pinch implosion,'' Phys Plasmas 15, 012701 (2008) J.A.Halbleib et al, ``ITS: the integrated TIGER series of electron/photon transport codes-Version 3.0,'' IEEE Trans on Nuclear Sci, 39, 1025 (1992)

Investigation on Convergence – Divergence Nozzle Shape for Microscale Channel in Harvesting Kinetic Energy

NASA Astrophysics Data System (ADS)

Zakaria, M. S.; Zairi, S.; Misbah, M. N.; Saifizi, M.; Rakawi, Izzudin

2018-03-01

This paper presents performance evaluation of nozzle shapes on microscale channel by employing different types of NACA airfoils profile and conventional profile. The deploying nozzle used are NACA 0012, NACA 0021 and NACA 0024 airfoils while for conventional convergence-divergence nozzle diameter ratio (d2 / d1) in the range from 1/4 to 3/4 are applied. These nozzles are assembled on rectangular cross sectional microscale channel which has designated constant fluid flow velocity at the channel inlet. This study revealed reduction on diameter ratio increased dramatically fluid velocity but further reduction on diameter ratio exposed fluid flow to fluctuate which slightly slowing down the fluid velocity. Nevertheless, curved NACA profiles are favourable for convergence – divergence nozzle in microscale channel as it significantly improved flow characteristics by enhancing fluid velocity and resultant kinetic energy as compared to conventional profile.

Accurate simulation of backscattering spectra in the presence of sharp resonances

NASA Astrophysics Data System (ADS)

Barradas, N. P.; Alves, E.; Jeynes, C.; Tosaki, M.

2006-06-01

In elastic backscattering spectrometry, the shape of the observed spectrum due to resonances in the nuclear scattering cross-section is influenced by many factors. If the energy spread of the beam before interaction is larger than the resonance width, then a simple convolution with the energy spread on exit and with the detection system resolution will lead to a calculated spectrum with a resonance much sharper than the observed signal. Also, the yield from a thin layer will not be calculated accurately. We have developed an algorithm for the accurate simulation of backscattering spectra in the presence of sharp resonances. Albeit approximate, the algorithm leads to dramatic improvements in the quality and accuracy of the simulations. It is simple to implement and leads to only small increases of the calculation time, being thus suitable for routine data analysis. We show different experimental examples, including samples with roughness and porosity.

3D Topology Preserving Flows for Viewpoint-Based Cortical Unfolding

PubMed Central

Rocha, Kelvin R.; Sundaramoorthi, Ganesh; Yezzi, Anthony J.; Prince, Jerry L.

2009-01-01

We present a variational method for unfolding of the cortex based on a user-chosen point of view as an alternative to more traditional global flattening methods, which incur more distortion around the region of interest. Our approach involves three novel contributions. The first is an energy function and its corresponding gradient flow to measure the average visibility of a region of interest of a surface with respect to a given viewpoint. The second is an additional energy function and flow designed to preserve the 3D topology of the evolving surface. The third is a method that dramatically improves the computational speed of the 3D topology preservation approach by creating a tree structure of the 3D surface and using a recursion technique. Experiments results show that the proposed approach can successfully unfold highly convoluted surfaces such as the cortex while preserving their topology. PMID:19960105

Van der Waals Interactions of Organic Molecules on Semiconductor and Metal Surfaces: a Comparative Study

NASA Astrophysics Data System (ADS)

Li, Guo; Cooper, Valentino; Cho, Jun-Hyung; Tamblyn, Isaac; Du, Shixuan; Neaton, Jeffrey; Gao, Hong-Jun; Zhang, Zhenyu

2012-02-01

We present a comparative investigation of vdW interactions of the organic molecules on semiconductor and metal surfaces using the DFT method implemented with vdW-DF. For styrene/H-Si(100), the vdW interactions reverse the effective intermolecular interaction from repulsive to attractive, ensuring preferred growth of long wires as observed experimentally. We further propose that an external E field and the selective creation of Si dangling bonds can drastically improve the ordered arrangement of the molecular nanowires [1]. For BDA/Au(111), the vdW interactions not only dramatically enhances the adsorption energies, but also significantly changes the molecular configurations. In the azobenzene/Ag(111) system, vdW-DF produces superior predictions for the adsorption energy than those obtained with other vdW corrected DFT approaches, providing evidence for the applicability of the vdW-DF method [2].

NREL’s Advanced Analytics Research for Buildings – Social Media Version

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Forty percent of the total energy consumption in the United States comes from buildings. Working together, we can dramatically shrink that number. NREL’s advanced analytics research has already proven to reduce energy use, save money, and stabilize the grid.

Liquid Sunshine to Fuel Your Car (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Breunig, Lloyd

"Liquid Sunshine to Fuel Your Car" was submitted by the Center for Lignocellulose Structure and Formation (CLSF) to the "Life at the Frontiers of Energy Research" video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CLSF is directed by Daniel Cosgrove at Pennsylvania State University and is a partnership of scientists from three institutions: Penn State (lead), North Carolina State University, and Virginia Tech University. The Office of Basic Energy Sciences in the U.S. Department of Energy's Officemore » of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Lignocellulose Structure and Formation is 'to dramatically increase our fundamental knowledge of the formation and physical interactions of bio-polymer networks in plant cell walls to provide a basis for improved methods for converting biomass into fuels.' Research topics are: biofuels (biomass), membrane, interfacial characterization, matter by design, and self-assembly.« less

Liquid Sunshine to Fuel Your Car (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

ScienceCinema

Cosgrove, Daniel (Director, Center for Lignocellulose Structure and Formation); CLSF Staff

2017-12-09

'Liquid Sunshine to Fuel Your Car' was submitted by the Center for Lignocellulose Structure and Formation (CLSF) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CLSF is directed by Daniel Cosgrove at Pennsylvania State University and is a partnership of scientists from three institutions: Penn State (lead), North Caroline State University, and Virginia Tech University. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Lignocellulose Structure and Formation is 'to dramatically increase our fundamental knowledge of the formation and physical interactions of bio-polymer networks in plant cell walls to provide a basis for improved methods for converting biomass into fuels.' Research topics are: biofuels (biomass), membrane, interfacial characterization, matter by design, and self-assembly.

Autonomic Materials for Smarter, Safer, Longer-Lasting Batteries (A "Life at the Frontiers of Energy Research" contest entry from the 2011 Energy Frontier Research Centers (EFRCs) Summit and Forum)

ScienceCinema

Thackeray, Michael (Director, Center for Electrical Energy Storage); CEES Staff

2017-12-09

'Autonomic Materials for Smarter, Safer, Longer-Lasting Batteries' was submitted by the Center for Electrical Energy Storage (CEES) to the 'Life at the Frontiers of Energy Research' video contest at the 2011 Science for Our Nation's Energy Future: Energy Frontier Research Centers (EFRCs) Summit and Forum. Twenty-six EFRCs created short videos to highlight their mission and their work. CEES, an EFRC directed by Michael Thackery at Argonne National Laboratory is a partnership of scientists from three institutions: ANL (lead), Northwestern University, and the University of Illinois at Urbana-Champaign. The Office of Basic Energy Sciences in the U.S. Department of Energy's Office of Science established the 46 Energy Frontier Research Centers (EFRCs) in 2009. These collaboratively-organized centers conduct fundamental research focused on 'grand challenges' and use-inspired 'basic research needs' recently identified in major strategic planning efforts by the scientific community. The overall purpose is to accelerate scientific progress toward meeting the nation's critical energy challenges. The mission of the Center for Electrical Energy Storage is 'to acquire a fundamental understanding of interfacial phenomena controlling electrochemical processes that will enable dramatic improvements in the properties and performance of energy storage devices, notable Li ion batteries.' Research topics are: electrical energy storage, batteries, battery electrodes, electrolytes, adaptive materials, interfacial characterization, matter by design; novel materials synthesis, charge transport, and defect tolerant materials.

Energy Transport in the Thermosphere During the Solar Storms of April 2002

NASA Technical Reports Server (NTRS)

Mlynczak, Martin G.; Martin-Torres, F. J.; Crowley, Geoff; Funke, Bernd; Lu, Gang; Russell, III, James M.; Kozyra, Janet; Sharma, Ramesh; Gordley, Larry; Paxton, Larry

2005-01-01

The dramatic solar storm events of April 2002 deposited a large amount of energy into the Earth's upper atmosphere, substantially altering the thermal structure, the chemical composition, the dynamics, and the radiative environment. We examine the flow of energy within the thermosphere during this storm period from the perspective of infrared radiation transport and heat conduction. Observations from the SABER instrument on the TIMED satellite are coupled with computations based on the ASPEN thermospheric general circulation model to assess the energy flow. The dominant radiative response is associated with dramatically enhanced infrared emission from nitric oxide at 5.3 microns from which a total of approx. 7.7 x 10(exp 23) ergs of energy are radiated during the storm. Energy loss rates due to NO emission exceed 2200 Kelvin per day. In contrast, energy loss from carbon dioxide emission at 15 microns is only approx. 2.3% that of nitric oxide. Atomic oxygen emission at 63 microns is essentially constant during the storm. Energy loss from molecular heat conduction may be as large as 3.8% of the NO emission. These results confirm the "natural thermostat" effect of nitric oxide emission as the primary mechanism by which storm energy is lost from the thermosphere below 210 km.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lherbier, Louis, W.; Novotnak, David, J.; Herling, Darrell, R.

Hot forming processes such as forging, die casting and glass forming require tooling that is subjected to high temperatures during the manufacturing of components. Current tooling is adversely affected by prolonged exposure at high temperatures. Initial studies were conducted to determine the root cause of tool failures in a number of applications. Results show that tool failures vary and depend on the operating environment under which they are used. Major root cause failures include (1) thermal softening, (2) fatigue and (3) tool erosion, all of which are affected by process boundary conditions such as lubrication, cooling, process speed, etc. Whilemore » thermal management is a key to addressing tooling failures, it was clear that new tooling materials with superior high temperature strength could provide improved manufacturing efficiencies. These efficiencies are based on the use of functionally graded materials (FGM), a new subset of hybrid tools with customizable properties that can be fabricated using advanced powder metallurgy manufacturing technologies. Modeling studies of the various hot forming processes helped identify the effect of key variables such as stress, temperature and cooling rate and aid in the selection of tooling materials for specific applications. To address the problem of high temperature strength, several advanced powder metallurgy nickel and cobalt based alloys were selected for evaluation. These materials were manufactured into tooling using two relatively new consolidation processes. One process involved laser powder deposition (LPD) and the second involved a solid state dynamic powder consolidation (SSDPC) process. These processes made possible functionally graded materials (FGM) that resulted in shaped tooling that was monolithic, bi-metallic or substrate coated. Manufacturing of tooling with these processes was determined to be robust and consistent for a variety of materials. Prototype and production testing of FGM tooling showed the benefits of the nickel and cobalt based powder metallurgy alloys in a number of applications evaluated. Improvements in tool life ranged from three (3) to twenty (20) or more times than currently used tooling. Improvements were most dramatic where tool softening and deformation were the major cause of tool failures in hot/warm forging applications. Significant improvement was also noted in erosion of aluminum die casting tooling. Cost and energy savings can be realized as a result of increased tooling life, increased productivity and a reduction in scrap because of improved dimensional controls. Although LPD and SSDPC tooling usually have higher acquisition costs, net tooling costs per component produced drops dramatically with superior tool performance. Less energy is used to manufacture the tooling because fewer tools are required and less recycling of used tools are needed for the hot forming process. Energy is saved during the component manufacturing cycle because more parts can be produced in shorter periods of time. Energy is also saved by minimizing heating furnace idling time because of less downtime for tooling changes.« less

A Nuclear Renaissance: The Role of Nuclear Power in Mitigating Climate Change

NASA Astrophysics Data System (ADS)

Winslow, Anne

2011-06-01

The U. N. Framework Convention on Climate Change calls for the stabilization of greenhouse gas (GHG) emissions at double the preindustrial atmospheric carbon dioxide concentration to avoid dangerous anthropogenic interference with the climate system. To achieve this goal, carbon emissions in 2050 must not exceed their current level, despite predictions of a dramatic increase in global electricity demand. The need to reduce GHG emissions and simultaneously provide for additional electricity demand has led to a renewed interest in the expansion of alternatives to fossil fuels—particularly renewable energy and nuclear power. As renewable energy sources are often constrained by the intermittency of natural energy forms, scale-ability concerns, cost and environmental barriers, many governments and even prominent environmentalist turn to nuclear energy as a source of clean, reliable base-load electricity. Described by some as a "nuclear renaissance", this trend of embracing nuclear power as a tool to mitigate climate change will dramatically influence the feasibility of emerging nuclear programs around the world.

A Nuclear Renaissance: The Role of Nuclear Power in Mitigating Climate Change

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winslow, Anne

2011-06-28

The U. N. Framework Convention on Climate Change calls for the stabilization of greenhouse gas (GHG) emissions at double the preindustrial atmospheric carbon dioxide concentration to avoid dangerous anthropogenic interference with the climate system. To achieve this goal, carbon emissions in 2050 must not exceed their current level, despite predictions of a dramatic increase in global electricity demand. The need to reduce GHG emissions and simultaneously provide for additional electricity demand has led to a renewed interest in the expansion of alternatives to fossil fuels--particularly renewable energy and nuclear power. As renewable energy sources are often constrained by the intermittencymore » of natural energy forms, scale-ability concerns, cost and environmental barriers, many governments and even prominent environmentalist turn to nuclear energy as a source of clean, reliable base-load electricity. Described by some as a ''nuclear renaissance'', this trend of embracing nuclear power as a tool to mitigate climate change will dramatically influence the feasibility of emerging nuclear programs around the world.« less

Two decades of progress in understanding and control of laser plasma instabilities in indirect drive inertial fusion

DOE PAGES

Montgomery, David S.

2016-04-14

Our understanding of laser-plasma instability (LPI) physics has improved dramatically over the past two decades through advancements in experimental techniques, diagnostics, and theoretical and modeling approaches. We have progressed from single-beam experiments—ns pulses with ~kJ energy incident on hundred-micron-scale target plasmas with ~keV electron temperatures—to ones involving nearly 2 MJ energy in 192 beams onto multi-mm-scale plasmas with temperatures ~4 keV. At the same time, we have also been able to use smaller-scale laser facilities to substantially improve our understanding of LPI physics and evaluate novel approaches to their control. These efforts have led to a change in paradigm formore » LPI research, ushering in an era of engineering LPI to accomplish specific objectives, from tuning capsule implosion symmetry to fixing nonlinear saturation of LPI processes at acceptable levels to enable the exploration of high energy density physics in novel plasma regimes. A tutorial is provided that reviews the progress in the field from the vantage of the foundational LPI experimental results. The pedagogical framework of the simplest models of LPI will be employed, but attention will also be paid to settings where more sophisticated models are needed to understand the observations. Prospects for the application of our improved understanding for inertial fusion (both indirect- and direct-drive) and other applications will also be discussed.« less

White butterflies as solar photovoltaic concentrators

PubMed Central

Shanks, Katie; Senthilarasu, S.; ffrench-Constant, Richard H.; Mallick, Tapas K.

2015-01-01

Man’s harvesting of photovoltaic energy requires the deployment of extensive arrays of solar panels. To improve both the gathering of thermal and photovoltaic energy from the sun we have examined the concept of biomimicry in white butterflies of the family Pieridae. We tested the hypothesis that the V-shaped posture of basking white butterflies mimics the V-trough concentrator which is designed to increase solar input to photovoltaic cells. These solar concentrators improve harvesting efficiency but are both heavy and bulky, severely limiting their deployment. Here, we show that the attachment of butterfly wings to a solar cell increases its output power by 42.3%, proving that the wings are indeed highly reflective. Importantly, and relative to current concentrators, the wings improve the power to weight ratio of the overall structure 17-fold, vastly expanding their potential application. Moreover, a single mono-layer of scale cells removed from the butterflies’ wings maintained this high reflectivity showing that a single layer of scale cell-like structures can also form a useful coating. As predicted, the wings increased the temperature of the butterflies’ thorax dramatically, showing that the V-shaped basking posture of white butterflies has indeed evolved to increase the temperature of their flight muscles prior to take-off. PMID:26227341

Narrative review: the role of leptin in human physiology: emerging clinical applications.

PubMed

Kelesidis, Theodore; Kelesidis, Iosif; Chou, Sharon; Mantzoros, Christos S

2010-01-19

Leptin is a hormone secreted by adipose tissue in direct proportion to amount of body fat. The circulating leptin levels serve as a gauge of energy stores, thereby directing the regulation of energy homeostasis, neuroendocrine function, and metabolism. Persons with congenital deficiency are obese, and treatment with leptin results in dramatic weight loss through decreased food intake and possible increased energy expenditure. However, most obese persons are resistant to the weight-reducing effects of leptin. Recent studies suggest that leptin is physiologically more important as an indicator of energy deficiency, rather than energy excess, and may mediate adaptation by driving increased food intake and directing neuroendocrine function to converse energy, such as inducing hypothalamic hypogonadism to prevent fertilization. Current studies investigate the role of leptin in weight-loss management because persons who have recently lost weight have relative leptin deficiency that may drive them to regain weight. Leptin deficiency is also evident in patients with diet- or exercise-induced hypothalamic amenorrhea and lipoatrophy. Replacement of leptin in physiologic doses restores ovulatory menstruation in women with hypothalamic amenorrhea and improves metabolic dysfunction in patients with lipoatrophy, including lipoatrophy associated with HIV or highly active antiretroviral therapy. The applications of leptin continue to grow and will hopefully soon be used therapeutically.

Assessment of Orbital-Optimized Third-Order Møller-Plesset Perturbation Theory and Its Spin-Component and Spin-Opposite Scaled Variants for Thermochemistry and Kinetics.

PubMed

Soydaş, Emine; Bozkaya, Uğur

2013-03-12

An assessment of the OMP3 method and its spin-component and spin-scaled variants for thermochemistry and kinetics is presented. For reaction energies of closed-shell systems, the CCSD, SCS-MP3, and SCS-OMP3 methods show better performances than other considered methods, and no significant improvement is observed due to orbital optimization. For barrier heights, OMP3 and SCS-OMP3 provide the lowest mean absolute deviations. The MP3 method yields considerably higher errors, and the spin scaling approaches do not help to improve upon MP3, but worsen it. For radical stabilization energies, the CCSD, OMP3, and SCS-OMP3 methods exhibit noticeably better performances than MP3 and its variants. Our results demonstrate that if the reference wave function suffers from a spin-contamination, then the MP3 methods dramatically fail. On the other hand, the OMP3 method and its variants can tolerate the spin-contamination in the reference wave function. For overall evaluation, we conclude that OMP3 is quite helpful, especially in electronically challenged systems, such as free radicals or transition states where spin contamination dramatically deteriorates the quality of the canonical MP3 and SCS-MP3 methods. Both OMP3 and CCSD methods scale as n(6), where n is the number of basis functions. However, the OMP3 method generally converges in much fewer iterations than CCSD. In practice, OMP3 is several times faster than CCSD in energy computations. Further, the stationary properties of OMP3 make it much more favorable than CCSD in the evaluation of analytic derivatives. For OMP3, the analytic gradient computations are much less expensive than CCSD. For the frequency computation, both methods require the evaluation of the perturbed amplitudes and orbitals. However, in the OMP3 case there is still a significant computational time savings due to simplifications in the analytic Hessian expression owing to the stationary property of OMP3. Hence, the OMP3 method emerges as a very useful tool for computational quantum chemistry.

Heat conduction tuning by hyperbranched nanophononic metamaterials

NASA Astrophysics Data System (ADS)

Li, Bing; Tan, K. T.; Christensen, Johan

2018-05-01

Phonon dispersion and thermal conduction properties of hyperbranched nanostructures with unique topological complexity are theoretically and numerically investigated in this research. We present analytical cantilever-in-mass models to analyze and control the inherent resonance hybridization in hyperbranched nanomembranes containing different configurations and cross sections. We show that these local resonances hosted by hyperbranched nanopillars can generate numerous flat bands in the phonon dispersion relation and dramatically lower the group velocities, consequently resulting in a significant reduction of the thermal conductivity. The applicability of the proposed analytical models in thermal conductivity tuning is demonstrated, and a superior performance in reducing the heat flux in nano-structured membranes is exhibited, which can potentially lead to improved thermoelectric energy conversion devices.

Intergenerational Energy Balance Interventions: A Systematic Literature Review

ERIC Educational Resources Information Center

Swanson, Mark; Studts, Christina R.; Bardach, Shoshana H.; Bersamin, Andrea; Schoenberg, Nancy E.

2011-01-01

Many nations have witnessed a dramatic increase in the prevalence of obesity and overweight across their population. Recognizing the influence of the household environment on energy balance has led many researchers to suggest that intergenerational interventions hold promise for addressing this epidemic. Yet few comprehensive reviews of…

Energy extraction from atmospheric turbulence to improve flight vehicle performance

NASA Astrophysics Data System (ADS)

Patel, Chinmay Karsandas

Small 'bird-sized' Unmanned Aerial Vehicles (UAVs) have now become practical due to technological advances in embedded electronics, miniature sensors and actuators, and propulsion systems. Birds are known to take advantage of wind currents to conserve energy and fly long distances without flapping their wings. This dissertation explores the possibility of improving the performance of small UAVs by extracting the energy available in atmospheric turbulence. An aircraft can gain energy from vertical gusts by increasing its lift in regions of updraft and reducing its lift in downdrafts - a concept that has been known for decades. Starting with a simple model of a glider flying through a sinusoidal gust, a parametric optimization approach is used to compute the minimum gust amplitude and optimal control input required for the glider to sustain flight without losing energy. For small UAVs using optimal control inputs, sinusoidal gusts with amplitude of 10--15% of the cruise speed are sufficient to keep the aircraft aloft. The method is then modified and extended to include random gusts that are representative of natural turbulence. A procedure to design optimal control laws for energy extraction from realistic gust profiles is developed using a Genetic Algorithm (GA). A feedback control law is designed to perform well over a variety of random gusts, and not be tailored for one particular gust. A small UAV flying in vertical turbulence is shown to obtain average energy savings of 35--40% with the use of a simple control law. The design procedure is also extended to determine optimal control laws for sinusoidal as well as turbulent lateral gusts. The theoretical work is complemented by experimental validation using a small autonomous UAV. The development of a lightweight autopilot and UAV platform is presented. Flight test results show that active control of the lift of an autonomous glider resulted in approximately 46% average energy savings compared to glides with fixed control surfaces. Statistical analysis of test samples shows that 19% of the active control test runs resulted in no energy loss, thus demonstrating the potential of the 'gust soaring' concept to dramatically improve the performance of small UAVs.

Optimizing Distributed Energy Resources and building retrofits with the strategic DER-CAModel

DOE PAGES

Stadler, M.; Groissböck, M.; Cardoso, G.; ...

2014-08-05

The pressuring need to reduce the import of fossil fuels as well as the need to dramatically reduce CO 2 emissions in Europe motivated the European Commission (EC) to implement several regulations directed to building owners. Most of these regulations focus on increasing the number of energy efficient buildings, both new and retrofitted, since retrofits play an important role in energy efficiency. Overall, this initiative results from the realization that buildings will have a significant impact in fulfilling the 20/20/20-goals of reducing the greenhouse gas emissions by 20%, increasing energy efficiency by 20%, and increasing the share of renewables tomore » 20%, all by 2020. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is an optimization tool used to support DER investment decisions, typically by minimizing total annual costs or CO 2 emissions while providing energy services to a given building or microgrid site. This document shows enhancements made to DER-CAM to consider building retrofit measures along with DER investment options. Specifically, building shell improvement options have been added to DER-CAM as alternative or complementary options to investments in other DER such as PV, solar thermal, combined heat and power, or energy storage. The extension of the mathematical formulation required by the new features introduced in DER-CAM is presented and the resulting model is demonstrated at an Austrian Campus building by comparing DER-CAM results with and without building shell improvement options. Strategic investment results are presented and compared to the observed investment decision at the test site. Results obtained considering building shell improvement options suggest an optimal weighted average U value of about 0.53 W/(m 2K) for the test site. This result is approximately 25% higher than what is currently observed in the building, suggesting that the retrofits made in 2002 were not optimal. Furthermore, the results obtained with DER-CAM illustrate the complexity of interactions between DER and passive measure options, showcasing the need for a holistic optimization approach to effectively optimize energy costs and CO 2 emissions. Lastly, the simultaneous optimization of building shell improvements and DER investments enables building owners to take one step further towards nearly zero energy buildings (nZEB) or nearly zero carbon emission buildings (nZCEB), and therefore support the 20/20/20 goals.« less

Optimizing Distributed Energy Resources and building retrofits with the strategic DER-CAModel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stadler, M.; Groissböck, M.; Cardoso, G.

The pressuring need to reduce the import of fossil fuels as well as the need to dramatically reduce CO 2 emissions in Europe motivated the European Commission (EC) to implement several regulations directed to building owners. Most of these regulations focus on increasing the number of energy efficient buildings, both new and retrofitted, since retrofits play an important role in energy efficiency. Overall, this initiative results from the realization that buildings will have a significant impact in fulfilling the 20/20/20-goals of reducing the greenhouse gas emissions by 20%, increasing energy efficiency by 20%, and increasing the share of renewables tomore » 20%, all by 2020. The Distributed Energy Resources Customer Adoption Model (DER-CAM) is an optimization tool used to support DER investment decisions, typically by minimizing total annual costs or CO 2 emissions while providing energy services to a given building or microgrid site. This document shows enhancements made to DER-CAM to consider building retrofit measures along with DER investment options. Specifically, building shell improvement options have been added to DER-CAM as alternative or complementary options to investments in other DER such as PV, solar thermal, combined heat and power, or energy storage. The extension of the mathematical formulation required by the new features introduced in DER-CAM is presented and the resulting model is demonstrated at an Austrian Campus building by comparing DER-CAM results with and without building shell improvement options. Strategic investment results are presented and compared to the observed investment decision at the test site. Results obtained considering building shell improvement options suggest an optimal weighted average U value of about 0.53 W/(m 2K) for the test site. This result is approximately 25% higher than what is currently observed in the building, suggesting that the retrofits made in 2002 were not optimal. Furthermore, the results obtained with DER-CAM illustrate the complexity of interactions between DER and passive measure options, showcasing the need for a holistic optimization approach to effectively optimize energy costs and CO 2 emissions. Lastly, the simultaneous optimization of building shell improvements and DER investments enables building owners to take one step further towards nearly zero energy buildings (nZEB) or nearly zero carbon emission buildings (nZCEB), and therefore support the 20/20/20 goals.« less

Basics of particle therapy I: physics

PubMed Central

Park, Seo Hyun

2011-01-01

With the advance of modern radiation therapy technique, radiation dose conformation and dose distribution have improved dramatically. However, the progress does not completely fulfill the goal of cancer treatment such as improved local control or survival. The discordances with the clinical results are from the biophysical nature of photon, which is the main source of radiation therapy in current field, with the lower linear energy transfer to the target. As part of a natural progression, there recently has been a resurgence of interest in particle therapy, specifically using heavy charged particles, because these kinds of radiations serve theoretical advantages in both biological and physical aspects. The Korean government is to set up a heavy charged particle facility in Korea Institute of Radiological & Medical Sciences. This review introduces some of the elementary physics of the various particles for the sake of Korean radiation oncologists' interest. PMID:22984664

Energy Storage Systems Evaluation | Transportation Research | NREL

Science.gov Websites

extreme climates can have a dramatic impact on batteries and energy storage systems. Graph with numerous -E drive data to assess the vehicle batteries' value in second-use applications. Figure courtesy of could potentially absorb a large quantity of repurposed EV batteries. NREL's system evaluation project

Enhanced thermoelectric efficiency of porous silicene nanoribbons.

PubMed

Sadeghi, Hatef; Sangtarash, Sara; Lambert, Colin J

2015-03-30

There is a critical need to attain new sustainable materials for direct upgrade of waste heat to electrical energy via the thermoelectric effect. Here we demonstrate that the thermoelectric performance of silicene nanoribbons can be improved dramatically by introducing nanopores and tuning the Fermi energy. We predict that values of electronic thermoelectric figure of merit ZTe up to 160 are achievable, provided the Fermi energy is located approximately 100 meV above the charge neutrality point. Including the effect of phonons yields a value for the full figure of merit of ZT = 3.5. Furthermore the sign of the thermopower S can be varied with achievable values as high as S = +/- 500 μV/K. As a method of tuning the Fermi energy, we analyse the effect of doping the silicene with either a strong electron donor (TTF) or a strong electron acceptor (TCNQ) and demonstrate that adsorbed layers of the former increases ZTe to a value of 3.1, which is insensitive to temperature over the range 100 K - 400 K. This combination of a high, temperature-insensitive ZTe, and the ability to choose the sign of the thermopower identifies nanoporous silicene as an ideal thermoelectric material with the potential for unprecedented performance.

Fabrication of lanthanum-doped thorium dioxide by high-energy ball milling and spark plasma sintering

NASA Astrophysics Data System (ADS)

Scott, Spencer M.; Yao, Tiankai; Lu, Fengyuan; Xin, Guoqing; Zhu, Weiguang; Lian, Jie

2017-03-01

High-energy ball milling was used to synthesize Th1-xLaxO2-0.5x (x = 0.09, 0.23) solid solutions, as well as improve the sinterability of ThO2 powders. Dense La-doped ThO2 pellets with theoretical density above 94% were consolidated by spark plasma sintering at temperatures above 1400 °C for 20 min, and the densification behavior and the non-equilibrium effects on phase and structure were investigated. A lattice contraction of the SPS-densified pellets occurred with increasing ball milling duration, and a secondary phase with increased La-content was observed in La-doped pellets. A dependence on the La-content and sintering duration for the onset of localized phase segregation has been proposed. The effects of high-energy ball milling, La-content, and phase formation on the thermal diffusivity were also studied for La-doped ThO2 pellets by laser flash measurement. Increasing La-content and high energy ball milling time decreases thermal diffusivity; while the sintering peak temperature and holding time beyond 1600 °C dramatically altered the temperature dependence of the thermal diffusivity beyond 600 °C.

Analysis of Technological Innovation and Environmental Performance Improvement in Aviation Sector

PubMed Central

Lee, Joosung; Mo, Jeonghoon

2011-01-01

The past oil crises have caused dramatic improvements in fuel efficiency in all industrial sectors. The aviation sector—aircraft manufacturers and airlines—has also made significant efforts to improve the fuel efficiency through more advanced jet engines, high-lift wing designs, and lighter airframe materials. However, the innovations in energy-saving aircraft technologies do not coincide with the oil crisis periods. The largest improvement in aircraft fuel efficiency took place in the 1960s while the high oil prices in the 1970s and on did not induce manufacturers or airlines to achieve a faster rate of innovation. In this paper, we employ a historical analysis to examine the socio-economic reasons behind the relatively slow technological innovation in aircraft fuel efficiency over the last 40 years. Based on the industry and passenger behaviors studied and prospects for alternative fuel options, this paper offers insights for the aviation sector to shift toward more sustainable technological options in the medium term. Second-generation biofuels could be the feasible option with a meaningful reduction in aviation’s lifecycle environmental impact if they can achieve sufficient economies of scale. PMID:22016716

Analysis of technological innovation and environmental performance improvement in aviation sector.

PubMed

Lee, Joosung; Mo, Jeonghoon

2011-09-01

The past oil crises have caused dramatic improvements in fuel efficiency in all industrial sectors. The aviation sector-aircraft manufacturers and airlines-has also made significant efforts to improve the fuel efficiency through more advanced jet engines, high-lift wing designs, and lighter airframe materials. However, the innovations in energy-saving aircraft technologies do not coincide with the oil crisis periods. The largest improvement in aircraft fuel efficiency took place in the 1960s while the high oil prices in the 1970s and on did not induce manufacturers or airlines to achieve a faster rate of innovation. In this paper, we employ a historical analysis to examine the socio-economic reasons behind the relatively slow technological innovation in aircraft fuel efficiency over the last 40 years. Based on the industry and passenger behaviors studied and prospects for alternative fuel options, this paper offers insights for the aviation sector to shift toward more sustainable technological options in the medium term. Second-generation biofuels could be the feasible option with a meaningful reduction in aviation's lifecycle environmental impact if they can achieve sufficient economies of scale.

Energy-level alignment and open-circuit voltage at graphene/polymer interfaces: theory and experiment

NASA Astrophysics Data System (ADS)

Noori, Keian; Konios, Dimitrios; Stylianakis, Minas M.; Kymakis, Emmanuel; Giustino, Feliciano

2016-03-01

Functionalized graphene promises to become a key component of novel solar cell architectures, owing to its versatile ability to act either as transparent conductor, electron acceptor, or buffer layer. In spite of this promise, the solar energy conversion efficiency of graphene-based devices falls short of the performance of competing solution-processable photovoltaic technologies. Here we address the question of the maximum achievable open-circuit voltage of all-organic graphene: polymer solar cells using a combined theoretical/experimental approach, going from the atomic scale level to the device level. Our calculations on very large atomistic models of the graphene/polymer interface indicate that the ideal open-circuit voltage approaches one volt, and that epoxide functional groups can have a dramatic effect on the photovoltage. Our predictions are confirmed by direct measurements on complete devices where we control the concentration of functional groups via chemical reduction. Our findings indicate that the selective removal of epoxide groups and the use of ultradisperse polymers are key to achieving graphene solar cells with improved energy conversion efficiency.

Perturbation theory corrections to the two-particle reduced density matrix variational method.

PubMed

Juhasz, Tamas; Mazziotti, David A

2004-07-15

In the variational 2-particle-reduced-density-matrix (2-RDM) method, the ground-state energy is minimized with respect to the 2-particle reduced density matrix, constrained by N-representability conditions. Consider the N-electron Hamiltonian H(lambda) as a function of the parameter lambda where we recover the Fock Hamiltonian at lambda=0 and we recover the fully correlated Hamiltonian at lambda=1. We explore using the accuracy of perturbation theory at small lambda to correct the 2-RDM variational energies at lambda=1 where the Hamiltonian represents correlated atoms and molecules. A key assumption in the correction is that the 2-RDM method will capture a fairly constant percentage of the correlation energy for lambda in (0,1] because the nonperturbative 2-RDM approach depends more significantly upon the nature rather than the strength of the two-body Hamiltonian interaction. For a variety of molecules we observe that this correction improves the 2-RDM energies in the equilibrium bonding region, while the 2-RDM energies at stretched or nearly dissociated geometries, already highly accurate, are not significantly changed. At equilibrium geometries the corrected 2-RDM energies are similar in accuracy to those from coupled-cluster singles and doubles (CCSD), but at nonequilibrium geometries the 2-RDM energies are often dramatically more accurate as shown in the bond stretching and dissociation data for water and nitrogen. (c) 2004 American Institute of Physics.

Design of exceptionally strong and conductive Cu alloys beyond the conventional speculation via the interfacial energy-controlled dispersion of γ-Al2O3 nanoparticles

PubMed Central

Zeon Han, Seung; Kim, Kwang Ho; Kang, Joonhee; Joh, Hongrae; Kim, Sang Min; Ahn, Jee Hyuk; Lee, Jehyun; Lim, Sung Hwan; Han, Byungchan

2015-01-01

The development of Cu-based alloys with high-mechanical properties (strength, ductility) and electrical conductivity plays a key role over a wide range of industrial applications. Successful design of the materials, however, has been rare due to the improvement of mutually exclusive properties as conventionally speculated. In this paper, we demonstrate that these contradictory material properties can be improved simultaneously if the interfacial energies of heterogeneous interfaces are carefully controlled. We uniformly disperse γ-Al2O3 nanoparticles over Cu matrix, and then we controlled atomic level morphology of the interface γ-Al2O3//Cu by adding Ti solutes. It is shown that the Ti dramatically drives the interfacial phase transformation from very irregular to homogeneous spherical morphologies resulting in substantial enhancement of the mechanical property of Cu matrix. Furthermore, the Ti removes impurities (O and Al) in the Cu matrix by forming oxides leading to recovery of the electrical conductivity of pure Cu. We validate experimental results using TEM and EDX combined with first-principles density functional theory (DFT) calculations, which all consistently poise that our materials are suitable for industrial applications. PMID:26616045

Design of exceptionally strong and conductive Cu alloys beyond the conventional speculation via the interfacial energy-controlled dispersion of γ-Al2O3 nanoparticles.

PubMed

Han, Seung Zeon; Kim, Kwang Ho; Kang, Joonhee; Joh, Hongrae; Kim, Sang Min; Ahn, Jee Hyuk; Lee, Jehyun; Lim, Sung Hwan; Han, Byungchan

2015-11-30

The development of Cu-based alloys with high-mechanical properties (strength, ductility) and electrical conductivity plays a key role over a wide range of industrial applications. Successful design of the materials, however, has been rare due to the improvement of mutually exclusive properties as conventionally speculated. In this paper, we demonstrate that these contradictory material properties can be improved simultaneously if the interfacial energies of heterogeneous interfaces are carefully controlled. We uniformly disperse γ-Al2O3 nanoparticles over Cu matrix, and then we controlled atomic level morphology of the interface γ-Al2O3//Cu by adding Ti solutes. It is shown that the Ti dramatically drives the interfacial phase transformation from very irregular to homogeneous spherical morphologies resulting in substantial enhancement of the mechanical property of Cu matrix. Furthermore, the Ti removes impurities (O and Al) in the Cu matrix by forming oxides leading to recovery of the electrical conductivity of pure Cu. We validate experimental results using TEM and EDX combined with first-principles density functional theory (DFT) calculations, which all consistently poise that our materials are suitable for industrial applications.

Intensive Study on the Catalytical Behavior of N-Methylphenothiazine as a Soluble Mediator to Oxidize the Li2O2 Cathode of the Li-O2 Battery.

PubMed

Feng, Ningning; Mu, Xiaowei; Zhang, Xueping; He, Ping; Zhou, Haoshen

2017-02-01

Aprotic Li-O 2 batteries have attracted worldwide interest owing to their ultrahigh theoretical energy density. However, the practical Li-O 2 batteries still suffer from high charge overpotential and low energy efficiency resulting from the sluggish kinetics in electrochemically oxidizing the insulating lithium peroxide (Li 2 O 2 ). Recently, dissolved redox mediators in the electrolyte have enabled the effective catalytic oxidation of Li 2 O 2 at the liquid-solid interface. Here, we report that the incorporation of N-methylphenothiazine (MPT), as a redox shuttle in Li-O 2 batteries, provides a dramatic reduction in charge overpotential to 0.67 V and an improved round-trip efficiency close to 76%. Moreover, the efficacy of MPT in Li-O 2 cells was further investigated by various characterizations. On charging, MPT + cations are first generated electrochemically at the cathode surface and subsequently oxidize the solid discharge products Li 2 O 2 through a chemical reaction. Furthermore, the presence of MPT has been demonstrated to improve the cycling stability of the cells and suppress side reactions arising from carbon and electrolytes at high potentials.

Development of a Telescope for Medium-Energy Gamma-Ray Astronomy

NASA Technical Reports Server (NTRS)

Hunter, Stanley D.

2010-01-01

Since the launch of AGILE and FERMI, the scientific progress in high-energy (E(sub gamma) greater than approximately 200 MeV) gamma-ray science has been, and will continue to be dramatic. Both of these telescopes cover a broad energy range from approximately 20 MeV to greater than 10 GeV. However, neither instrument is optimized for observations below approximately 200 MeV where many astrophysical objects exhibit unique, transitory behavior, such as spectral breaks, bursts, and flares. Hence, while significant progress from current observations is expected, there will nonetheless remain a significant sensitivity gap in the medium-energy (approximately 0.1-200 MeV) regime; the lower end of this range remains largely unexplored whereas the upper end will allow comparison with FERMI data. Tapping into this unexplored regime requires significant improvements in sensitivity. A major emphasis of modern detector development, with the goal of providing significant improvements in sensitivity in the medium-energy regime, focuses on high-resolution electron tracking. The Three-Dimensional Track Imager (3-DTI) technology being developed at GSFC provides high resolution tracking of the electron-positron pair from gamma-ray interactions from 5 to 200 MeV. The 3-DTI consists of a time projection chamber (TPC) and 2-D cross-strip microwell detector (MWD). The low-density and homogeneous design of the 3-DTI, offers unprecedented sensitivity by providing angular resolution near the kinematic limit. Electron tracking also enables measurement of gamma-ray polarization, a new tool to study astrophysical phenomenon. We describe the design, fabrication, and performance of a 30x30x30 cubic centimeters 3-DTI detector prototype of a medium-energy gamma-ray telescope.

Development of a Telescope for Medium-Energy Gamma-ray Astronomy

NASA Technical Reports Server (NTRS)

Sunter, Stan

2012-01-01

Since the launch of AGILE and FERMI, the scientific progress in high-energy (Eg greater than approximately 200 MeV) gamma-ray science has been, and will continue to be dramatic. Both of these telescopes cover a broad energy range from approximately 20 MeV to greater than 10 GeV. However, neither instrument is optimized for observations below approximately 200 MeV where many astrophysical objects exhibit unique, transitory behavior, such as spectral breaks, bursts, and flares. Hence, while significant progress from current observations is expected, there will nonetheless remain a significant sensitivity gap in the medium-energy (approximately 0.1-200 MeV) regime; the lower end of this range remains largely unexplored whereas the upper end will allow comparison with FERMI data. Tapping into this unexplored regime requires significant improvements in sensitivity. A major emphasis of modern detector development, with the goal of providing significant improvements in sensitivity in the medium-energy regime, focuses on high-resolution electron tracking. The Three-Dimensional Track Imager (3-DTI) technology being developed at GSFC provides high resolution tracking of the electron-positron pair from gamma-ray interactions from 5 to 200 MeV. The 3-DTI consists of a time projection chamber (TPC) and 2-D cross-strip microwell detector (MWD). The low-density and homogeneous design of the 3-DTI, offers unprecedented sensitivity by providing angular resolution near the kinematic limit. Electron tracking also enables measurement of gamma-ray polarization, a new tool to study astrophysical phenomenon. We describe the design, fabrication, and performance of a 30x30x30 cm3 3-DTI detector prototype of a medium-energy gamma-ray telescope.

Negotiating for Change: Modifying Collective Bargaining Agreements for School Turnaround

ERIC Educational Resources Information Center

Weinberg, Rebecca

2011-01-01

Dramatically improving student achievement in a school that has been failing for many years requires dramatically different conditions. Only the most effective teachers and leaders should be in the building, and the leadership must have the flexibility to respond strategically to the needs of the students, with regular input from teachers.…

Fulcrum of Change: Leveraging 50 States to Turn around 5000 Schools

ERIC Educational Resources Information Center

Rhim, Lauren Morando; Redding, Sam

2011-01-01

In 2010, unprecedented levels of resources began to flow through state education agencies (SEAs) to support dramatic change in persistently low-performing schools under the expanded federal School Improvement Grant (SIG) program. The challenge for states is to leverage the federal investment to drive dramatic and sustainable change efforts in…

The influence of environment and energy macro surroundings on the development of tourism in the 21st century.

PubMed

Jovicić, Dobrica

2012-06-01

Trying to anticipate the future of tourism may be a particularly fraught task. However, this does not mean that trying to predict the future of tourism is not without value. From a business perspective, examining the future enables firms to anticipate new business conditions and develop new strategies. From a destination perspective, reflections on the future enable consideration of how to maintain or improve the qualities of a destination. The paper is focused on an analysis of the impacts of the energy and ecological macro environments on tourism trends in 21st century. Mass international tourism has thrived on the abundant and cheap supply of energy, and this may be about to change as the world moves towards 'Peak Oil'. The resultant scarcity and high price of all energy fuels will produce changes in human activities, specifically in tourism. The basis of the health of the economy is the health of the environment. Therefore issues of global environmental changes are increasingly influencing consideration of trends in tourism. In this looming transitional era tourism needs to make some dramatic changes to harmonize with the new realities of a post-energy world affected additionaly by global warming and other environmental changes.

Evaluation of Emerging Energy-Efficient Heterogeneous Computing Platforms for Biomolecular and Cellular Simulation Workloads.

PubMed

Stone, John E; Hallock, Michael J; Phillips, James C; Peterson, Joseph R; Luthey-Schulten, Zaida; Schulten, Klaus

2016-05-01

Many of the continuing scientific advances achieved through computational biology are predicated on the availability of ongoing increases in computational power required for detailed simulation and analysis of cellular processes on biologically-relevant timescales. A critical challenge facing the development of future exascale supercomputer systems is the development of new computing hardware and associated scientific applications that dramatically improve upon the energy efficiency of existing solutions, while providing increased simulation, analysis, and visualization performance. Mobile computing platforms have recently become powerful enough to support interactive molecular visualization tasks that were previously only possible on laptops and workstations, creating future opportunities for their convenient use for meetings, remote collaboration, and as head mounted displays for immersive stereoscopic viewing. We describe early experiences adapting several biomolecular simulation and analysis applications for emerging heterogeneous computing platforms that combine power-efficient system-on-chip multi-core CPUs with high-performance massively parallel GPUs. We present low-cost power monitoring instrumentation that provides sufficient temporal resolution to evaluate the power consumption of individual CPU algorithms and GPU kernels. We compare the performance and energy efficiency of scientific applications running on emerging platforms with results obtained on traditional platforms, identify hardware and algorithmic performance bottlenecks that affect the usability of these platforms, and describe avenues for improving both the hardware and applications in pursuit of the needs of molecular modeling tasks on mobile devices and future exascale computers.

WIRE: Weather Intelligence for Renewable Energies

NASA Astrophysics Data System (ADS)

Heimo, A.; Cattin, R.; Calpini, B.

2010-09-01

Renewable energies such as wind and solar energy will play an important, even decisive role in order to mitigate and adapt to the projected dramatic consequences to our society and environment due to climate change. Due to shrinking fossil resources, the transition to more and more renewable energy shares is unavoidable. But, as wind and solar energy are strongly dependent on highly variable weather processes, increased penetration rates will also lead to strong fluctuations in the electricity grid which need to be balanced. Proper and specific forecasting of ‘energy weather' is a key component for this. Therefore, it is today appropriate to scientifically address the requirements to provide the best possible specific weather information for forecasting the energy production of wind and solar power plants within the next minutes up to several days. Towards such aims, Weather Intelligence will first include developing dedicated post-processing algorithms coupled with weather prediction models and with past and/or online measurement data especially remote sensing observations. Second, it will contribute to investigate the difficult relationship between the highly intermittent weather dependent power production and concurrent capacities such as transport and distribution of this energy to the end users. Selecting, resp. developing surface-based and satellite remote sensing techniques well adapted to supply relevant information to the specific post-processing algorithms for solar and wind energy production short-term forecasts is a major task with big potential. It will lead to improved energy forecasts and help to increase the efficiency of the renewable energy productions while contributing to improve the management and presumably the design of the energy grids. The second goal will raise new challenges as this will require first from the energy producers and distributors definitions of the requested input data and new technologies dedicated to the management of power plants and electricity grids and second from the meteorological measurement community to deliver suitable, short term high quality forecasts to fulfill these requests with emphasis on highly variable weather conditions and spatially distributed energy productions often located in complex terrain. This topic has been submitted for a new COST Action under the title "Short-Term High Resolution Wind and Solar Energy Production Forecasts".

Nanocrystals feel the heat

NASA Astrophysics Data System (ADS)

Liang, Liangliang; Liu, Xiaogang

2018-03-01

Phosphors often suffer luminescence quenching at elevated temperatures. Now, thermal quenching can be combated with surface phonon-assisted energy transfer, enabling the luminescence of ultrasmall upconversion nanophosphors to be dramatically enhanced.

DATABASE OF LANDFILL GAS TO ENERGY PROJECTS IN THE UNITED STATES

EPA Science Inventory

The paper discusses factors influencing the increase of landfill gas to energy (LFG-E) projects in the U.S. and presents recent statistics from a database,. There has been a dramatic increase in the number of LFG-E projects in the U.S., due to such factors as implementation of t...

Nonperturbative theory for the dispersion self-energy of atoms

NASA Astrophysics Data System (ADS)

Thiyam, Priyadarshini; Persson, C.; Brevik, I.; Sernelius, Bo E.; Boström, Mathias

2014-11-01

We go beyond the approximate series expansions used in the dispersion theory of finite-size atoms. We demonstrate that a correct, and nonperturbative, theory dramatically alters the dispersion self-energies of atoms. The nonperturbed theory gives as much as 100 % corrections compared to the traditional series-expanded theory for the smaller noble gas atoms.

Wind Energy Systems.

ERIC Educational Resources Information Center

Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

During the 1920s and 1930s, millions of wind energy systems were used on farms and other locations far from utility lines. However, with passage of the Rural Electrification Act in 1939, cheap electricity was brought to rural areas. After that, the use of wind machines dramatically declined. Recently, the rapid rise in fuel prices has led to a…

On the Dielectric Constant for Acetanilide: Experimental Measurements and Effect on Energy Transport

NASA Astrophysics Data System (ADS)

Careri, G.; Compatangelo, E.; Christiansen, P. L.; Halding, J.; Skovgaard, O.

1987-01-01

Experimental measurements of the dielectric constant for crystalline acetanilide powder for temperatures ranging from - 140°C to 20°C and for different hydration levels are presented. A Davydov-soliton computer model predicts dramatic changes in the energy transport and storage for typically increased values of the dielectric constant.

Enhanced Charge Extraction of Li-Doped TiO₂ for Efficient Thermal-Evaporated Sb₂S₃ Thin Film Solar Cells.

PubMed

Lan, Chunfeng; Luo, Jingting; Lan, Huabin; Fan, Bo; Peng, Huanxin; Zhao, Jun; Sun, Huibin; Zheng, Zhuanghao; Liang, Guangxing; Fan, Ping

2018-02-28

We provided a new method to improve the efficiency of Sb₂S₃ thin film solar cells. The TiO₂ electron transport layers were doped by lithium to improve their charge extraction properties for the thermal-evaporated Sb₂S₃ solar cells. The Mott-Schottky curves suggested a change of energy band and faster charge transport in the Li-doped TiO₂ films. Compared with the undoped TiO₂, Li-doped mesoporous TiO₂ dramatically improved the photo-voltaic performance of the thermal-evaporated Sb₂S₃ thin film solar cells, with the average power conversion efficiency ( PCE ) increasing from 1.79% to 4.03%, as well as the improved open-voltage ( V oc ), short-circuit current ( J sc ) and fill factors. The best device based on Li-doped TiO₂ achieved a power conversion efficiency up to 4.42% as well as a V oc of 0.645 V, which are the highest values among the reported thermal-evaporated Sb₂S₃ solar cells. This study showed that Li-doping on TiO₂ can effectively enhance the charge extraction properties of electron transport layers, offering a new strategy to improve the efficiency of Sb₂S₃-based solar cells.

Chinese hotel general managers' perspectives on energy-saving practices

NASA Astrophysics Data System (ADS)

Zhu, Yidan

As hotels' concern about sustainability and budget-control is growing steadily, energy-saving issues have become one of the important management concerns hospitality industry face. By executing proper energy-saving practices, previous scholars believed that hotel operation costs can decrease dramatically. Moreover, they believed that conducting energy-saving practices may eventually help the hotel to gain other benefits such as an improved reputation and stronger competitive advantage. The energy-saving issue also has become a critical management problem for the hotel industry in China. Previous research has not investigated energy-saving in China's hotel segment. To achieve a better understanding of the importance of energy-saving, this document attempts to present some insights into China's energy-saving practices in the tourist accommodations sector. Results of the study show the Chinese general managers' attitudes toward energy-saving issues and the differences among the diverse hotel managers who responded to the study. Study results indicate that in China, most of the hotels' energy bills decrease due to the implementation of energy-saving equipments. General managers of hotels in operation for a shorter period of time are typically responsible for making decisions about energy-saving issues; older hotels are used to choosing corporate level concerning to this issue. Larger Chinese hotels generally have official energy-saving usage training sessions for employees, but smaller Chinese hotels sometimes overlook the importance of employee training. The study also found that for the Chinese hospitality industry, energy-saving practices related to electricity are the most efficient and common way to save energy, but older hotels also should pay attention to other ways of saving energy such as water conservation or heating/cooling system.

The Big Glamorous Monster (or Lady Gaga's Adventures at Sea): Improving Student Writing through Dramatic Approaches in Schools

ERIC Educational Resources Information Center

Lee, Bridget Kiger; Enciso, Patricia

2017-01-01

Drawing on assets-oriented, sociocultural theories of imagination and learning, the authors argue that the improvisational qualities and expanded resources of dramatic approaches to teaching make a positive difference in the quality of and persistence in students' story writing. The authors describe findings from a controlled quasi-experimental…

How to Know when Dramatic Change Is on Track: Leading Indicators of School Turnarounds

ERIC Educational Resources Information Center

Kowal, Julie; Ableidinger, Joe

2011-01-01

In recent years, national policymakers have placed new emphasis on "school turnarounds" as a strategy for rapid, dramatic improvement in chronically failing schools, calling on education leaders to turn around performance in the 5,000 lowest-achieving schools nationwide. This goal may seem daunting, given the dismal success rates of…

Electron-excited energy dispersive X-ray spectrometry at high speed and at high resolution: silicon drift detectors and microcalorimeters.

PubMed

Newbury, Dale E

2006-12-01

Two recent developments in X-ray spectrometer technology provide dramatic improvements in analytical capabilities that impact the frontiers of electron microscopy. Silicon drift detectors (SDD) use the same physics as silicon (lithium) energy dispersive spectrometers [Si(Li) EDS] but differ in design: only 10% of the thickness of the Si(Li) EDS with an anode area below 0.1 mm2 and a complex rear surface electrode pattern that creates a lateral internal charge collection field. The SDD equals or betters the Si(Li) EDS in most measures of performance. For output versus input count rate, the SDD exceeds the Si(Li) EDS by a factor of 5 to 10 for the same resolution. This high throughput can benefit analytical measurements that are count limited, such as X-ray mapping and trace measurements. The microcalorimeter EDS determines the X-ray energy by measuring the temperature rise in a metal absorber. Operating at 100 mK, the microcalorimeter EDS achieves resolution of 2-5 eV over a photon energy range of 200 eV to 10 keV in energy dispersive operation, eliminating most peak interference situations and providing high peak-to-background to detect low fluorescence yield peaks. Chemical bonding effects on low energy (< 2 keV) peak shapes can be measured.

Nanomanufacturing and sustainability: opportunities and challenges

NASA Astrophysics Data System (ADS)

Busnaina, Ahmed A.; Mead, Joey; Isaacs, Jacqueline; Somu, Sivasubramanian

2013-10-01

New nanomanufacturing technologies, although still in research labs, present a great opportunity to drastically reduce the cost of making nanostructures on a large scale and at high-rates. Such new bottom-up directed assembly-based approaches involve adding materials selectively thereby both reducing waste and the number of required processes. Directed assembly-based processes are conducted at room pressure and temperatures which significantly reduces the cost of nanomanufacturing equipment and tools, ensuring long-term sustainability by reducing energy, consumables, and waste costs. This paradigm shift in nanomanufacturing will unleash not only a wave of creativity in sustainable nanomanufacturing but lessons learnt along the way can be used in various other sectors. Along with the exquisite technological promise that nanotechnology holds, nano-enabled products are heralded as a means for energy and resource reduction, resulting in potential manufacturing cost reductions and further, for potential improvements to environmental remediation. Sustainable nanomanufacturing will, by dramatically lowering current nanomanufacturing barriers, spur innovation, and the creation of entirely new industries by leveling the playing and ultimately leading to the democratization of nanomanufacturing.

A comprehensive comparison between thermodynamic perturbation theory and first-order mean spherical approximation: Based on discrete potentials with hard core

NASA Astrophysics Data System (ADS)

Zhou, Shiqi; Zhou, Run

2017-08-01

Using the TL (Tang and Lu, 1993) method, Ornstein-Zernike integral equation is solved perturbatively under the mean spherical approximation (MSA) for fluid with potential consisting of a hard sphere plus square-well plus square-shoulder (HS + SW + SS) to obtain first-order analytic expressions of radial distribution function (RDF), second-order direct correlation function, and semi-analytic expressions for common thermodynamic properties. A comprehensive comparison between the first-order MSA and high temperature series expansion (HTSE) to third-, fifth- and seventh-order is performed over a wide parameter range for both a HS + SW and the HS + SW + SS model fluids by using corresponding ;exact; Monte Carlo results as a reference; although the HTSE is carried out up to seventh-order, and not to the first order as the first-order MSA the comparison is considered fair from a calculation complexity perspective. It is found that the performance of the first-order MSA is dramatically model-dependent: as target potentials go from the HS + SW to the HS + SW + SS, (i) there is a dramatic dropping of performance of the first-order MSA expressions in calculating the thermodynamic properties, especially both the excess internal energy and constant volume excess heat capacity of the HS + SW + SS model cannot be predicted even qualitatively correctly. (ii) One tendency is noticed that the first-order MSA gets more reliable with increasing temperatures in dealing with the pressure, excess Helmholtz free energy, excess enthalpy and excess chemical potential. (iii) Concerning the RDF, the first-order MSA is not as disappointing as it displays in the cases of thermodynamics. (iv) In the case of the HS + SW model, the first-order MSA solution is shown to be quantitatively correct in calculating the pressure and excess chemical potential even if the reduced temperatures are as low as 0.8. On the other hand, the seventh-order HTSE is less model-dependent; in most cases of the HS + SW and the HS + SW + SS models, the seventh-order HTSE improves the fifth- and third-order HTSE in both thermodynamic properties and RDF, and the improvements are very demonstrable in both the excess internal energy and constant volume excess heat capacity; for very limited cases, the seventh-order HTSE improves the fifth-order HTSE only within lower density domain and even shows a bit of inadaptation over higher density domain.

Socio-dramatic affective-relational intervention for adolescents with asperger syndrome & high functioning autism: pilot study.

PubMed

Lerner, Matthew D; Mikami, Amori Yee; Levine, Karen

2011-01-01

This study examined the effectiveness of a novel intervention called 'socio-dramatic affective-relational intervention' (SDARI), intended to improve social skills among adolescents with Asperger syndrome and high functioning autism diagnoses. SDARI adapts dramatic training activities to focus on in vivo practice of areas of social skill deficit among this population. SDARI was administered as a six-week summer program in a community human service agency. Nine SDARI participants and eight age- and diagnosis-group matched adolescents not receiving SDARI were compared on child- and parent-report of social functioning at three week intervals beginning six weeks prior to intervention and ending six weeks post-intervention. Hierarchical Linear Modeling (HLM) was used to estimate growth trends between groups to assess treatment outcomes and post-treatment maintenance. Results indicated significant improvement and post-treatment maintenance among SDARI participants on several measures of child social functioning. Implications for practice and research are discussed.

Case study comparison of two pellet heating facilities in southeastern Alaska

Treesearch

David Nicholls; Allen Brackley; Robert Deering; Daniel Parrent; Brian Kleinhenz; Craig. Moore

2016-01-01

Over the past decade, wood-energy use in Alaska has grown dramatically. Since 2000, several dozen new wood-energy installations have been established, with numerous others in the design or construction phase. This case study report compares two wood-pellet heating systems in Juneau, Alaska. The Tlingit-Haida Regional Housing Authority, a native housing authority that...

Workforce Development and Wind for Schools (Poster)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Newcomb, C.; Baring-Gould, I.

2012-06-01

As the United States dramatically expands wind energy deployment, the industry is faced with the need to quickly develop a skilled workforce and to address public acceptance. Wind Powering America's Wind for Schools project addresses these challenges. This poster, produced for the American Wind Energy Association's annual WINDPOWER conference, provides an overview of the project, including objectives, methods, and results.

Nuclear Power and the Environment: Questions and Answers. Revised.

ERIC Educational Resources Information Center

Campana, Robert J.; Langer, Sidney

This publication is a complete revision of an earlier booklet brought on by the dramatic changes in the energy outlook of the United States that occurred in 1973 and 1974. The purpose of this document is to inform the public on the overall U.S. energy situation, in particular electricity generated from nuclear reactors and other sources. The…

Energy harvesting using AC machines with high effective pole count

NASA Astrophysics Data System (ADS)

Geiger, Richard Theodore

In this thesis, ways to improve the power conversion of rotating generators at low rotor speeds in energy harvesting applications were investigated. One method is to increase the pole count, which increases the generator back-emf without also increasing the I2R losses, thereby increasing both torque density and conversion efficiency. One machine topology that has a high effective pole count is a hybrid "stepper" machine. However, the large self inductance of these machines decreases their power factor and hence the maximum power that can be delivered to a load. This effect can be cancelled by the addition of capacitors in series with the stepper windings. A circuit was designed and implemented to automatically vary the series capacitance over the entire speed range investigated. The addition of the series capacitors improved the power output of the stepper machine by up to 700%. At low rotor speeds, with the addition of series capacitance, the power output of the hybrid "stepper" was more than 200% that of a similarly sized PMDC brushed motor. Finally, in this thesis a hybrid lumped parameter / finite element model was used to investigate the impact of number, shape and size of the rotor and stator teeth on machine performance. A typical off-the-shelf hybrid stepper machine has significant cogging torque by design. This cogging torque is a major problem in most small energy harvesting applications. In this thesis it was shown that the cogging and ripple torque can be dramatically reduced. These findings confirm that high-pole-count topologies, and specifically the hybrid stepper configuration, are an attractive choice for energy harvesting applications.

A Rural School/Community: A Case Study of a Dramatic Turnaround & Its Implications for School Improvement.

ERIC Educational Resources Information Center

Carlson, Robert V.

This paper presents a case study of a rural community exhibiting a dramatic turnaround in community support for a new school bond issue. Demographic change was partly responsible for the change in community attitudes, with two waves of immigration altering the long-term conservative orientation of this community. After a series of failed…

76 FR 9529 - Migratory Birds; Draft Eagle Conservation Plan Guidance

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-18

... maintenance of land-based, wind energy facilities in the United States. DATES: We must receive any comments or... electricity from wind turbines has increased dramatically in the range [[Page 9530

Star Power

ScienceCinema

None

2018-01-16

The U.S. Department of Energy's Princeton Plasma Physics Laboratory has released ''Star Power,'' a new informational video that uses dramatic and beautiful images and thought-provoking interviews to highlight the importance of the Laboratory's research into magnetic fusion.

Short-term weight loss attenuates local tissue inflammation and improves insulin sensitivity without affecting adipose inflammation in obese mice.

PubMed

Jung, Dae Young; Ko, Hwi Jin; Lichtman, Eben I; Lee, Eunjung; Lawton, Elizabeth; Ong, Helena; Yu, Kristine; Azuma, Yoshihiro; Friedline, Randall H; Lee, Ki Won; Kim, Jason K

2013-05-01

Obesity is a major cause of insulin resistance, and weight loss is shown to improve glucose homeostasis. But the underlying mechanism and the role of inflammation remain unclear. Male C57BL/6 mice were fed a high-fat diet (HFD) for 12 wk. After HFD, weight loss was induced by changing to a low-fat diet (LFD) or exercise with continuous HFD. The weight loss effects on energy balance and insulin sensitivity were determined using metabolic cages and hyperinsulinemic euglycemic clamps in awake mice. Diet and exercise intervention for 3 wk caused a modest weight loss and improved glucose homeostasis. Weight loss dramatically reduced local inflammation in skeletal muscle, liver, and heart but not in adipose tissue. Exercise-mediated weight loss increased muscle glucose metabolism without affecting Akt phosphorylation or lipid levels. LFD-mediated weight loss reduced lipid levels and improved insulin sensitivity selectively in liver. Both weight loss interventions improved cardiac glucose metabolism. These results demonstrate that a short-term weight loss with exercise or diet intervention attenuates obesity-induced local inflammation and selectively improves insulin sensitivity in skeletal muscle and liver. Our findings suggest that local factors, not adipose tissue inflammation, are involved in the beneficial effects of weight loss on glucose homeostasis.

Enhanced production of low energy electrons by alpha particle impact

PubMed Central

Kim, Hong-Keun; Titze, Jasmin; Schöffler, Markus; Trinter, Florian; Waitz, Markus; Voigtsberger, Jörg; Sann, Hendrik; Meckel, Moritz; Stuck, Christian; Lenz, Ute; Odenweller, Matthias; Neumann, Nadine; Schössler, Sven; Ullmann-Pfleger, Klaus; Ulrich, Birte; Fraga, Rui Costa; Petridis, Nikos; Metz, Daniel; Jung, Annika; Grisenti, Robert; Czasch, Achim; Jagutzki, Ottmar; Schmidt, Lothar; Jahnke, Till; Schmidt-Böcking, Horst; Dörner, Reinhard

2011-01-01

Radiation damage to living tissue stems not only from primary ionizing particles but to a substantial fraction from the dissociative attachment of secondary electrons with energies below the ionization threshold. We show that the emission yield of those low energy electrons increases dramatically in ion–atom collisions depending on whether or not the target atoms are isolated or embedded in an environment. Only when the atom that has been ionized and excited by the primary particle impact is in immediate proximity of another atom is a fragmentation route known as interatomic Coulombic decay (ICD) enabled. This leads to the emission of a low energy electron. Over the past decade ICD was explored in several experiments following photoionization. Most recent results show its observation even in water clusters. Here we show the quantitative role of ICD for the production of low energy electrons by ion impact, thus approaching a scenario closer to that of radiation damage by alpha particles: We choose ion energies on the maximum of the Bragg peak where energy is most efficiently deposited in tissue. We compare the electron production after colliding He+ ions on isolated Ne atoms and on Ne dimers (Ne2). In the latter case the Ne atom impacted is surrounded by a most simple environment already opening ICD as a deexcitation channel. As a consequence, we find a dramatically enhanced low energy electron yield. The results suggest that ICD may have a significant influence on cell survival after exposure to ionizing radiation. PMID:21730184

A fast scintillator Compton telescope for medium-energy gamma-ray astronomy

NASA Astrophysics Data System (ADS)

Bloser, Peter F.; Ryan, James M.; Legere, Jason S.; Julien, Manuel; Bancroft, Christopher M.; McConnell, Mark L.; Wallace, Mark; Kippen, R. Marc; Tornga, Shawn

2010-07-01

The field of medium-energy gamma-ray astronomy urgently needs a new mission to build on the success of the COMPTEL instrument on the Compton Gamma Ray Observatory. This mission must achieve sensitivity significantly greater than that of COMPTEL in order to advance the science of relativistic particle accelerators, nuclear astrophysics, and diffuse backgrounds, and bridge the gap between current and future hard X-ray missions and the high-energy Fermi mission. Such an increase in sensitivity can only come about via a dramatic decrease in the instrumental background. We are currently developing a concept for a low-background Compton telescope that employs modern scintillator technology to achieve this increase in sensitivity. Specifically, by employing LaBr3 scintillators for the calorimeter, one can take advantage of the unique speed and resolving power of this material to improve the instrument sensitivity while simultaneously enhancing its spectroscopic and imaging performance. Also, using deuterated organic scintillator in the scattering detector will reduce internal background from neutron capture. We present calibration results from a laboratory prototype of such an instrument, including time-of-flight, energy, and angular resolution, and compare them to simulation results using a detailed Monte Carlo model. We also describe the balloon payload we have built for a test flight of the instrument in the fall of 2010.

The role of intramolecular nonbonded interaction and angle sampling in single-step free energy perturbation

NASA Astrophysics Data System (ADS)

Chiang, Ying-Chih; Pang, Yui Tik; Wang, Yi

2016-12-01

Single-step free energy perturbation (sFEP) has often been proposed as an efficient tool for a quick free energy scan due to its straightforward protocol and the ability to recycle an existing molecular dynamics trajectory for free energy calculations. Although sFEP is expected to fail when the sampling of a system is inefficient, it is often expected to hold for an alchemical transformation between ligands with a moderate difference in their sizes, e.g., transforming a benzene into an ethylbenzene. Yet, exceptions were observed in calculations for anisole and methylaniline, which have similar physical sizes as ethylbenzene. In this study, we show that such exceptions arise from the sampling inefficiency on an unexpected rigid degree of freedom, namely, the bond angle θ. The distributions of θ differ dramatically between two end states of a sFEP calculation, i.e., the conformation of the ligand changes significantly during the alchemical transformation process. Our investigation also reveals the interrelation between the ligand conformation and the intramolecular nonbonded interactions. This knowledge suggests a best combination of the ghost ligand potential and the dual topology setting, which improves the accuracy in a single reference sFEP calculation by bringing down its error from around 5kBT to kBT.

Integrating a Silicon Solar Cell with a Triboelectric Nanogenerator via a Mutual Electrode for Harvesting Energy from Sunlight and Raindrops.

PubMed

Liu, Yuqiang; Sun, Na; Liu, Jiawei; Wen, Zhen; Sun, Xuhui; Lee, Shuit-Tong; Sun, Baoquan

2018-03-27

Solar cells, as promising devices for converting light into electricity, have a dramatically reduced performance on rainy days. Here, an energy harvesting structure that integrates a solar cell and a triboelectric nanogenerator (TENG) device is built to realize power generation from both sunlight and raindrops. A heterojunction silicon (Si) solar cell is integrated with a TENG by a mutual electrode of a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) film. Regarding the solar cell, imprinted PEDOT:PSS is used to reduce light reflection, which leads to an enhanced short-circuit current density. A single-electrode-mode water-drop TENG on the solar cell is built by combining imprinted polydimethylsiloxane (PDMS) as a triboelectric material combined with a PEDOT:PSS layer as an electrode. The increasing contact area between the imprinted PDMS and water drops greatly improves the output of the TENG with a peak short-circuit current of ∼33.0 nA and a peak open-circuit voltage of ∼2.14 V, respectively. The hybrid energy harvesting system integrated electrode configuration can combine the advantages of high current level of a solar cell and high voltage of a TENG device, promising an efficient approach to collect energy from the environment in different weather conditions.

Low-Energy Ions Injection and Acceleration at Oblique Shocks with Focused Transport Model

NASA Astrophysics Data System (ADS)

Zuo, P.; Zhang, M.; Feng, X. S.

2017-12-01

There is strong evidence that a small portion of suprathermal particles from hot coronal material or remnants of previous solar energetic particle (SEP) events serve as the source of large SEP events. Here we present a test particle simulation on the injection and acceleration of low-energy suprathermal particles by Laminar nonrelativistic oblique shocks in the framework of the focused transport theory, which is proved to contain all necessary physics of shock acceleration, but avoid the limitation of diffusive shock acceleration (DSA). We first characterize the role of cross-shock potential (CSP) on pickup ions (PUIs) acceleration. The CSP can affect the shape of the spectrum segment at lower energies, but it does not change the spectral index of the final power-law spectrum at high energies. It is found that a stronger CSP jump results in a dramatically improved injection efficiency. Our simulation results also show that the injection efficiency of PUIs is mass-dependent, which is lower for species with a higher mass. The injection efficiency as the function of Mach number, obliquity, injection speed, and shock strength is also calculated. It can be proved that the focused transport theory is an extension of DSA theory with the capability of predicting the efficiency of source particle injection.

A Data-Gathering Scheme with Joint Routing and Compressive Sensing Based on Modified Diffusion Wavelets in Wireless Sensor Networks.

PubMed

Gu, Xiangping; Zhou, Xiaofeng; Sun, Yanjing

2018-02-28

Compressive sensing (CS)-based data gathering is a promising method to reduce energy consumption in wireless sensor networks (WSNs). Traditional CS-based data-gathering approaches require a large number of sensor nodes to participate in each CS measurement task, resulting in high energy consumption, and do not guarantee load balance. In this paper, we propose a sparser analysis that depends on modified diffusion wavelets, which exploit sensor readings' spatial correlation in WSNs. In particular, a novel data-gathering scheme with joint routing and CS is presented. A modified ant colony algorithm is adopted, where next hop node selection takes a node's residual energy and path length into consideration simultaneously. Moreover, in order to speed up the coverage rate and avoid the local optimal of the algorithm, an improved pheromone impact factor is put forward. More importantly, theoretical proof is given that the equivalent sensing matrix generated can satisfy the restricted isometric property (RIP). The simulation results demonstrate that the modified diffusion wavelets' sparsity affects the sensor signal and has better reconstruction performance than DFT. Furthermore, our data gathering with joint routing and CS can dramatically reduce the energy consumption of WSNs, balance the load, and prolong the network lifetime in comparison to state-of-the-art CS-based methods.

An Overview of the NASA Energy and Water cycle Study (NEWS) and the North American Water Program (NAWP)

NASA Astrophysics Data System (ADS)

Houser, P. R.

2014-12-01

NEWS: 10 years ago, NASA established the NASA Energy and Water-cycle Study (NEWS), whose long-term grand challenge is to document and enable improved, observationally based, predictions of water and energy cycle consequences of Earth system variability and change. The NEWS program builds upon existing NASA-supported basic research in atmospheric physics and dynamics, radiation, climate modeling, and terrestrial hydrology. While these NASA programs fund research activities that address individual aspects of the global energy and water cycles, they are not specifically designed to generate a coordinated result. NEWS developed the first coordinated attempt to describe the complete global energy and water cycle using existing and forthcoming satellite and ground based observations, and laying the foundation for essential NEWS developments in model representations of atmospheric energy and water exchange processes. This comprehensive energy and water data analysis program exploited crucial datasets, some requiring complete re-processing, and new satellite measurements. NAWP: Dramatically changing climates has had an indelible impact on North America's water crisis. To decisively address these challenges, we recommend that NAWP coalesce an interdisciplinary, international and interagency effort to make significant contributions to continental- to decision-scale hydroclimate science and solutions. By entraining, integrating and coordinating the vast array of interdisciplinary observational and prediction resources available, NAWP will significantly advance skill in predicting, assessing and managing variability and changes in North American water resources. We adopt three challenges to organize NAWP efforts. The first deals with developing a scientific basis and tools for mitigating and adapting to changes in the water supply-demand balance. The second challenge is benchmarking; to use incomplete and uncertain observations to assess water storage and quality dynamics, and to characterize the information content of water cycle predictions in a way that allows for model improvement. The final challenge is to establish clear pathways to inform water managers, practitioners and decision makers about newly developed tools, observations and research results.

Clinical Information Systems - From Yesterday to Tomorrow.

PubMed

Gardner, R M

2016-06-30

To review the history of clinical information systems over the past twenty-five years and project anticipated changes to those systems over the next twenty-five years. Over 250 Medline references about clinical information systems, quality of patient care, and patient safety were reviewed. Books, Web resources, and the author's personal experience with developing the HELP system were also used. There have been dramatic improvements in the use and acceptance of clinical computing systems and Electronic Health Records (EHRs), especially in the United States. Although there are still challenges with the implementation of such systems, the rate of progress has been remarkable. Over the next twenty-five years, there will remain many important opportunities and challenges. These opportunities include understanding complex clinical computing issues that must be studied, understood and optimized. Dramatic improvements in quality of care and patient safety must be anticipated as a result of the use of clinical information systems. These improvements will result from a closer involvement of clinical informaticians in the optimization of patient care processes. Clinical information systems and computerized clinical decision support have made contributions to medicine in the past. Therefore, by using better medical knowledge, optimized clinical information systems, and computerized clinical decision, we will enable dramatic improvements in both the quality and safety of patient care in the next twenty-five years.

The use of Electrolyte Additives to Improve the High Temperature Resilience of Li-Ion Cells

NASA Technical Reports Server (NTRS)

Smart, Marshall C.; Lucht, B. L.; Ratnakumar, Bugga V.

2007-01-01

This viewgraph presentation reviews the use of electrolyte additves to improve the resillience of Lithium ion cells. The objective of this work is to identify lithium-ion electrolytes, which will lead to Li-ion cells with a wide operational temperature range (+60 to -60 C), and to develop Li-ion electrolytes which result in cells that display improved high temperature resilience. Significant improvement in the high temperature resilience of Li-ion cells containing these additives was observed, with the most dramatic benefit being displayed by addition of DMAc. When the electrochemical properties of the individual electrodes were analyzed, the degradation of the anode kinetics was slowed most dramatically by the incorporation of DMAc into the electrolytes. Whereas, the greatest retention in the cathode kinetics was observed in the cell containing the electrolyte with VC added.

Anaerobic fitness tests: what are we measuring?

PubMed

Van Praagh, Emmanuel

2007-01-01

Anaerobic fitness, during growth and development, has not received the same attention from researchers as aerobic fitness. This is surprising given the level of anaerobic energy used daily during childhood and adolescence. During physical activity and sport, the child is spontaneously more attracted to short-burst movements than to long-term activities. It is, however, well known that in anaerobic activities such as sprint cycling, sprint running or sprint swimming, the child's performance is distinctly poorer than that of the adult. This partly reflects the child's lesser ability to generate mechanical energy from chemical energy sources during short-term high-intensity work or exercise. Direct measurements of the rate or capacity of anaerobic pathways for energy turnover presents several ethical and methodological difficulties. Therefore, rather than measure energy supply, pediatric exercise scientists have concentrated on measuring short-term power output by means of standardized protocol tests such as short-term cycling power tests, running tests or vertical jump tests. There is, however, no perfect test and, therefore, it is important to acknowledge the benefits and limitations of each testing method. Mass-related short-term power output was shown to increase dramatically during growth and development, whereas the corresponding increase in peak blood lactate was considerably lower. This suggests that the observed difference between children and adolescents during short-term power output testing may be related to neuromuscular factors, hormonal factors and improved motor coordination.

Uncorrelated measurements of the cosmic expansion history and dark energy from supernovae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang Yun; Tegmark, Max; Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19104

We present a method for measuring the cosmic expansion history H(z) in uncorrelated redshift bins, and apply it to current and simulated type Ia supernova data assuming spatial flatness. If the matter density parameter {omega}{sub m} can be accurately measured from other data, then the dark-energy density history X(z)={rho}{sub X}(z)/{rho}{sub X}(0) can trivially be derived from this expansion history H(z). In contrast to customary 'black box' parameter fitting, our method is transparent and easy to interpret: the measurement of H(z){sup -1} in a redshift bin is simply a linear combination of the measured comoving distances for supernovae in that bin,more » making it obvious how systematic errors propagate from input to output. We find the Riess et al. (2004) gold sample to be consistent with the vanilla concordance model where the dark energy is a cosmological constant. We compare two mission concepts for the NASA/DOE Joint Dark-Energy Mission (JDEM), the Joint Efficient Dark-energy Investigation (JEDI), and the Supernova Accelaration Probe (SNAP), using simulated data including the effect of weak lensing (based on numerical simulations) and a systematic bias from K corrections. Estimating H(z) in seven uncorrelated redshift bins, we find that both provide dramatic improvements over current data: JEDI can measure H(z) to about 10% accuracy and SNAP to 30%-40% accuracy.« less

FDE-vdW: A van der Waals inclusive subsystem density-functional theory.

PubMed

Kevorkyants, Ruslan; Eshuis, Henk; Pavanello, Michele

2014-07-28

We present a formally exact van der Waals inclusive electronic structure theory, called FDE-vdW, based on the Frozen Density Embedding formulation of subsystem Density-Functional Theory. In subsystem DFT, the energy functional is composed of subsystem additive and non-additive terms. We show that an appropriate definition of the long-range correlation energy is given by the value of the non-additive correlation functional. This functional is evaluated using the fluctuation-dissipation theorem aided by a formally exact decomposition of the response functions into subsystem contributions. FDE-vdW is derived in detail and several approximate schemes are proposed, which lead to practical implementations of the method. We show that FDE-vdW is Casimir-Polder consistent, i.e., it reduces to the generalized Casimir-Polder formula for asymptotic inter-subsystems separations. Pilot calculations of binding energies of 13 weakly bound complexes singled out from the S22 set show a dramatic improvement upon semilocal subsystem DFT, provided that an appropriate exchange functional is employed. The convergence of FDE-vdW with basis set size is discussed, as well as its dependence on the choice of associated density functional approximant.

FDE-vdW: A van der Waals inclusive subsystem density-functional theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kevorkyants, Ruslan; Pavanello, Michele, E-mail: m.pavanello@rutgers.edu; Eshuis, Henk

2014-07-28

We present a formally exact van der Waals inclusive electronic structure theory, called FDE-vdW, based on the Frozen Density Embedding formulation of subsystem Density-Functional Theory. In subsystem DFT, the energy functional is composed of subsystem additive and non-additive terms. We show that an appropriate definition of the long-range correlation energy is given by the value of the non-additive correlation functional. This functional is evaluated using the fluctuation–dissipation theorem aided by a formally exact decomposition of the response functions into subsystem contributions. FDE-vdW is derived in detail and several approximate schemes are proposed, which lead to practical implementations of the method.more » We show that FDE-vdW is Casimir-Polder consistent, i.e., it reduces to the generalized Casimir-Polder formula for asymptotic inter-subsystems separations. Pilot calculations of binding energies of 13 weakly bound complexes singled out from the S22 set show a dramatic improvement upon semilocal subsystem DFT, provided that an appropriate exchange functional is employed. The convergence of FDE-vdW with basis set size is discussed, as well as its dependence on the choice of associated density functional approximant.« less

Historical carbon footprinting and implications for sustainability planning: a case study of the Pittsburgh region.

PubMed

Hoesly, Rachel; Blackhurst, Mike; Matthews, H Scott; Miller, Jeffrey F; Maples, Amy; Pettit, Matthew; Izard, Catherine; Fischbeck, Paul

2012-04-17

This study estimates fossil-based CO(2) emissions and energy use from 1900-2000 for Allegheny County, PA. Total energy use and emissions increased from 1900 to 1970, reflecting the significant industrial, economic, and population growth that occurred in Allegheny County. From 1970 to 2000, Allegheny County experienced a 30% decrease in total emissions and energy use from peak values, primarily because of a decline in industrial activity (40% decrease in value added) and the loss of a quarter of its population. Despite these dramatic economic and demographic transitions, per capita emissions remained stable from 1970 to 2000, buoyed by relatively stable or slightly increasing emissions in the commercial and transportation sectors. Allegheny County's history suggests the scale of change needed to achieve local emissions reductions may be significant; given years of major technological, economic, and demographic changes, per capita emissions in 1940 were nearly the same in 2000. Most local governments are planning emissions reductions rates that exceed 1% per year, which deviate significantly from historical trends. Our results suggest additional resources and improved planning paradigms are likely necessary to achieve significant emissions reductions, especially for areas where emissions are still increasing.

AMOEBA 2.0: A physics-first approach to biomolecular simulations

NASA Astrophysics Data System (ADS)

Rackers, Joshua; Ponder, Jay

The goal of the AMOEBA force field project is to use classical physics to understand and predict the nature of interactions between biological molecules. While making significant advances over the past decade, the ultimate goal of predicting binding energies with ``chemical accuracy'' remains elusive. The primary source of this inaccuracy comes from the physics of how molecules interact at short range. For example, despite AMOEBA's advanced treatment of electrostatics, the force field dramatically overpredicts the electrostatic energy of DNA stacking interactions. AMOEBA 2.0 works to correct these errors by including simple, first principles physics-based terms to account for the quantum mechanical nature of these short-range molecular interactions. We have added a charge penetration term that considerably improves the description of electrostatic interactions at short range. We are reformulating the polarization term of AMOEBA in terms of basic physics assertions. And we are reevaluating the van der Waals term to match ab initio energy decompositions. These additions and changes promise to make AMOEBA more predictive. By including more physical detail of the important short-range interactions of biological molecules, we hope to move closer to the ultimate goal of true predictive power.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Jong-Won; Hirao, Kimihiko, E-mail: hirao@riken.jp

Since the advent of hybrid functional in 1993, it has become a main quantum chemical tool for the calculation of energies and properties of molecular systems. Following the introduction of long-range corrected hybrid scheme for density functional theory a decade later, the applicability of the hybrid functional has been further amplified due to the resulting increased performance on orbital energy, excitation energy, non-linear optical property, barrier height, and so on. Nevertheless, the high cost associated with the evaluation of Hartree-Fock (HF) exchange integrals remains a bottleneck for the broader and more active applications of hybrid functionals to large molecular andmore » periodic systems. Here, we propose a very simple yet efficient method for the computation of long-range corrected hybrid scheme. It uses a modified two-Gaussian attenuating operator instead of the error function for the long-range HF exchange integral. As a result, the two-Gaussian HF operator, which mimics the shape of the error function operator, reduces computational time dramatically (e.g., about 14 times acceleration in C diamond calculation using periodic boundary condition) and enables lower scaling with system size, while maintaining the improved features of the long-range corrected density functional theory.« less

Oxygen transfer dynamics and activated sludge floc structure under different sludge retention times at low dissolved oxygen concentrations.

PubMed

Fan, Haitao; Liu, Xiuhong; Wang, Hao; Han, Yunping; Qi, Lu; Wang, Hongchen

2017-02-01

In activated sludge systems, the aeration process consumes the most energy. The energy cost can be dramatically reduced by decreasing the operating dissolved oxygen (DO) concentration. However, low DO may lead to incomplete nitrification and poor settling performance of activated sludge flocs (ASFs). This study investigates oxygen transfer dynamics and settling performances of activated sludge under different sludge retention times (SRTs) and DO conditions using microelectrodes and microscopic techniques. Our experimental results showed that with longer SRTs, treatment capacity and settling performances of activated sludge improved due to smaller floc size and less extracellular polymeric substances (EPS). Long-term low DO conditions produced larger flocs and more EPS per unit sludge, which produced a more extensive anoxic area and led to low oxygen diffusion performance in flocs. Long SRTs mitigated the adverse effects of low DO. According to the microelectrode analysis and fractal dimension determination, smaller floc size and less EPS in the long SRT system led to high oxygen diffusion property and more compact floc structure that caused a drop in the sludge volume index (SVI). In summary, our results suggested that long SRTs of activated sludge can improve the operating performance under low DO conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hydrogen-surfactant-assisted coherent growth of GaN on ZnO substrate

NASA Astrophysics Data System (ADS)

Zhang, Jingzhao; Zhang, Yiou; Tse, Kinfai; Zhu, Junyi

2018-01-01

Heterostructures of wurtzite based devices have attracted great research interest because of the tremendous success of GaN in light emitting diodes (LED) industry. High-quality GaN thin films on inexpensive and lattice matched ZnO substrates are both commercially and technologically desirable. Intrinsic wetting conditions, however, forbid such heterostructures as the energy of ZnO polar surfaces is much lower than that of GaN polar surfaces, resulting in 3D growth mode and poor crystal quality. Based on first-principles calculations, we propose the use of surfactant hydrogen to dramatically alter the growth mode of the heterostructures. Stable H-involved surface configurations and interfaces are investigated with the help of our newly developed modelling techniques. The temperature and chemical potential dependence of our proposed strategy, which is critical in experiments, is predicted by applying the experimental Gibbs free energy of H2. Our thermodynamic wetting condition analysis is a crucial step for the growth of GaN on ZnO, and we find that introducing H will not degrade the stability of ZnO substrate. This approach will allow the growth of high-quality GaN thin films on ZnO substrates. We believe that our new strategy may reduce the manufactory cost, improve the crystal quality, and improve the efficiency of GaN-based devices.

Hypothalamic Vitamin D Improves Glucose Homeostasis and Reduces Weight

PubMed Central

Arble, Deanna M.; Chambers, Adam P.; Gutierrez-Aguilar, Ruth; He, Yanlin; Xu, Yong; Gardner, David; Moore, David D.; Seeley, Randy J.; Sandoval, Darleen A.

2016-01-01

Despite clear associations between vitamin D deficiency and obesity and/or type 2 diabetes, a causal relationship is not established. Vitamin D receptors (VDRs) are found within multiple tissues, including the brain. Given the importance of the brain in controlling both glucose levels and body weight, we hypothesized that activation of central VDR links vitamin D to the regulation of glucose and energy homeostasis. Indeed, we found that small doses of active vitamin D, 1α,25-dihydroxyvitamin D3 (1,25D3) (calcitriol), into the third ventricle of the brain improved glucose tolerance and markedly increased hepatic insulin sensitivity, an effect that is dependent upon VDR within the paraventricular nucleus of the hypothalamus. In addition, chronic central administration of 1,25D3 dramatically decreased body weight by lowering food intake in obese rodents. Our data indicate that 1,25D3-mediated changes in food intake occur through action within the arcuate nucleus. We found that VDR colocalized with and activated key appetite-regulating neurons in the arcuate, namely proopiomelanocortin neurons. Together, these findings define a novel pathway for vitamin D regulation of metabolism with unique and divergent roles for central nervous system VDR signaling. Specifically, our data suggest that vitamin D regulates glucose homeostasis via the paraventricular nuclei and energy homeostasis via the arcuate nuclei. PMID:27217488

Inflation physics from the cosmic microwave background and large scale structure

NASA Astrophysics Data System (ADS)

Abazajian, K. N.; Arnold, K.; Austermann, J.; Benson, B. A.; Bischoff, C.; Bock, J.; Bond, J. R.; Borrill, J.; Buder, I.; Burke, D. L.; Calabrese, E.; Carlstrom, J. E.; Carvalho, C. S.; Chang, C. L.; Chiang, H. C.; Church, S.; Cooray, A.; Crawford, T. M.; Crill, B. P.; Dawson, K. S.; Das, S.; Devlin, M. J.; Dobbs, M.; Dodelson, S.; Doré, O.; Dunkley, J.; Feng, J. L.; Fraisse, A.; Gallicchio, J.; Giddings, S. B.; Green, D.; Halverson, N. W.; Hanany, S.; Hanson, D.; Hildebrandt, S. R.; Hincks, A.; Hlozek, R.; Holder, G.; Holzapfel, W. L.; Honscheid, K.; Horowitz, G.; Hu, W.; Hubmayr, J.; Irwin, K.; Jackson, M.; Jones, W. C.; Kallosh, R.; Kamionkowski, M.; Keating, B.; Keisler, R.; Kinney, W.; Knox, L.; Komatsu, E.; Kovac, J.; Kuo, C.-L.; Kusaka, A.; Lawrence, C.; Lee, A. T.; Leitch, E.; Linde, A.; Linder, E.; Lubin, P.; Maldacena, J.; Martinec, E.; McMahon, J.; Miller, A.; Mukhanov, V.; Newburgh, L.; Niemack, M. D.; Nguyen, H.; Nguyen, H. T.; Page, L.; Pryke, C.; Reichardt, C. L.; Ruhl, J. E.; Sehgal, N.; Seljak, U.; Senatore, L.; Sievers, J.; Silverstein, E.; Slosar, A.; Smith, K. M.; Spergel, D.; Staggs, S. T.; Stark, A.; Stompor, R.; Vieregg, A. G.; Wang, G.; Watson, S.; Wollack, E. J.; Wu, W. L. K.; Yoon, K. W.; Zahn, O.; Zaldarriaga, M.

2015-03-01

Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of CMB and large-scale structure (LSS) experiments are poised to test the leading paradigm for these earliest moments-the theory of cosmic inflation-and to detect the imprints of the inflationary epoch, thereby dramatically increasing our understanding of fundamental physics and the early universe. A future CMB experiment with sufficient angular resolution and frequency coverage that surveys at least 1% of the sky to a depth of 1 uK-arcmin can deliver a constraint on the tensor-to-scalar ratio that will either result in a 5 σ measurement of the energy scale of inflation or rule out all large-field inflation models, even in the presence of foregrounds and the gravitational lensing B-mode signal. LSS experiments, particularly spectroscopic surveys such as the Dark Energy Spectroscopic Instrument, will complement the CMB effort by improving current constraints on running of the spectral index by up to a factor of four, improving constraints on curvature by a factor of ten, and providing non-Gaussianity constraints that are competitive with the current CMB bounds.

Inflation Physics from the Cosmic Microwave Background and Large Scale Structure

NASA Technical Reports Server (NTRS)

Abazajian, K.N.; Arnold,K.; Austermann, J.; Benson, B.A.; Bischoff, C.; Bock, J.; Bond, J.R.; Borrill, J.; Buder, I.; Burke, D.L.;

Inflation physics from the cosmic microwave background and large scale structure

DOE PAGES

Abazajian, K. N.; Arnold, K.; Austermann, J.; ...

2014-06-26

Here, fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of CMB and large-scale structure (LSS) experiments are poised to test the leading paradigm for these earliest moments—the theory of cosmic inflation—and to detect the imprints of the inflationary epoch, thereby dramatically increasing our understanding of fundamental physics and the early universe. A future CMB experiment with sufficient angular resolution and frequency coverage that surveys at least 1% of the sky to amore » depth of 1 uK-arcmin can deliver a constraint on the tensor-to-scalar ratio that will either result in a 5σ measurement of the energy scale of inflation or rule out all large-field inflation models, even in the presence of foregrounds and the gravitational lensing B -mode signal. LSS experiments, particularly spectroscopic surveys such as the Dark Energy Spectroscopic Instrument, will complement the CMB effort by improving current constraints on running of the spectral index by up to a factor of four, improving constraints on curvature by a factor of ten, and providing non-Gaussianity constraints that are competitive with the current CMB bounds.« less

Social acceptability of bioenergy in the U.S

Treesearch

J. Peter Brosius; John Schelhas; Sarah Hitchner

2013-01-01

Global interest in bioenergy development has increased dramatically in recent years, due to its promise to reduce dependence on fossil fuel energy supplies, its contribution to global and national energy security, its potential to produce a carbon negative or neutral fuel source and to mitigate climate change, and its potential as a vehicle for rural development....

Faces of the Recovery Act: 1366 Technologies

ScienceCinema

Sachs, Ely; Mierlo, Frank van; Obama, Barack

2017-12-09

LEXINGTON, MA - At 1366 Technologies, Ely Sachs and Frank van Mierlo are using ARPA-E Recovery Act funding to dramatically reduce the costs of solar panel production. To read more about the project: http://arpa-e.energy.gov/FundedProjects.aspx#1366 To see more projects funded by the Recovery Act through ARPA-E: http://arpa-e.energy.gov/FundedProjects.aspx

'Leaner' lighting's dramatic impact.

PubMed

Kearney, Steve

2012-04-01

Steve Kearney, business manager for Newey & Eyre - Energy Saving 24/7, a team of 'energy experts' established early last year within one of the UK's leading distributors of electrical supplies, discusses the technologies and simple measures now available to reduce emissions and cut wastage generated by lighting in healthcare facilities, at a time when the NHS, especially, is under increasing pressure to reduce its carbon footprint.

Faces of the Recovery Act: 1366 Technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sachs, Ely; Mierlo, Frank van; Obama, Barack

2010-01-01

LEXINGTON, MA - At 1366 Technologies, Ely Sachs and Frank van Mierlo are using ARPA-E Recovery Act funding to dramatically reduce the costs of solar panel production. To read more about the project: http://arpa-e.energy.gov/FundedProjects.aspx#1366 To see more projects funded by the Recovery Act through ARPA-E: http://arpa-e.energy.gov/FundedProjects.aspx

Moving to a low-carbon future: perspectives on nuclear and alternative power sources.

PubMed

Morgan, M Granger

2007-11-01

This paper summarizes key findings from climate science to make the case that the United States (and ultimately the world) will need to dramatically reduce carbon dioxide emissions from the energy system over the next few decades. While transportation energy is an important consideration, the focus of this paper is on electric power. Today, the United States generates just over half of its electric power from coal. The average size-weighted age of the fleet of U.S. coal plants is 35 y, and many will have to be replaced in the next few years. If that capacity were to be replaced with new conventional coal plants, it would commit the nation (and the world) to many more decades of high carbon-dioxide emissions, or it would make the cost of meeting a future carbon-dioxide emission constraint much higher than it needs to be. A range of low- and no-carbon energy technologies offers great potential to create a portfolio of options that can dramatically reduce emissions. A few of the advantages and disadvantages of these technologies are discussed. Policy and regulatory advances that will be needed to move the energy system to a low-carbon future are identified.

Evaluation of Emerging Energy-Efficient Heterogeneous Computing Platforms for Biomolecular and Cellular Simulation Workloads

PubMed Central

Stone, John E.; Hallock, Michael J.; Phillips, James C.; Peterson, Joseph R.; Luthey-Schulten, Zaida; Schulten, Klaus

2016-01-01

Many of the continuing scientific advances achieved through computational biology are predicated on the availability of ongoing increases in computational power required for detailed simulation and analysis of cellular processes on biologically-relevant timescales. A critical challenge facing the development of future exascale supercomputer systems is the development of new computing hardware and associated scientific applications that dramatically improve upon the energy efficiency of existing solutions, while providing increased simulation, analysis, and visualization performance. Mobile computing platforms have recently become powerful enough to support interactive molecular visualization tasks that were previously only possible on laptops and workstations, creating future opportunities for their convenient use for meetings, remote collaboration, and as head mounted displays for immersive stereoscopic viewing. We describe early experiences adapting several biomolecular simulation and analysis applications for emerging heterogeneous computing platforms that combine power-efficient system-on-chip multi-core CPUs with high-performance massively parallel GPUs. We present low-cost power monitoring instrumentation that provides sufficient temporal resolution to evaluate the power consumption of individual CPU algorithms and GPU kernels. We compare the performance and energy efficiency of scientific applications running on emerging platforms with results obtained on traditional platforms, identify hardware and algorithmic performance bottlenecks that affect the usability of these platforms, and describe avenues for improving both the hardware and applications in pursuit of the needs of molecular modeling tasks on mobile devices and future exascale computers. PMID:27516922

NREL’s Advanced Analytics Research for Energy-Efficient Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kutscher, Chuck; Livingood, Bill; Wilson, Eric

At NREL, we believe in building better buildings. More importantly, high-performance buildings that can do more and be smarter than ever before. Forty percent of the total energy consumption in the United States comes from buildings. Working together, we can dramatically shrink that number. But first, it starts with the research: our observations, experiments, modeling, analysis, and more. NREL’s advanced analytics research has already proven to reduce energy use, save money, and stabilize the grid.

Quantum dynamics of tunneling dominated reactions at low temperatures

NASA Astrophysics Data System (ADS)

Hazra, Jisha; Balakrishnan, N.

2015-05-01

We report a quantum dynamics study of the Li + HF → LiF + H reaction at low temperatures of interest to cooling and trapping experiments. Contributions from non-zero partial waves are analyzed and results show narrow resonances in the energy dependence of the cross section that survive partial wave summation. The computations are performed using the ABC code and a simple modification of the ABC code that enables separate energy cutoffs for the reactant and product rovibrational energy levels is found to dramatically reduce the basis set size and computational expense. Results obtained using two ab initio electronic potential energy surfaces for the LiHF system show strong sensitivity to the choice of the potential. In particular, small differences in the barrier heights of the two potential surfaces are found to dramatically influence the reaction cross sections at low energies. Comparison with recent measurements of the reaction cross section (Bobbenkamp et al 2011 J. Chem. Phys. 135 204306) shows similar energy dependence in the threshold regime and an overall good agreement with experimental data compared to previous theoretical results. Also, usefulness of a recently introduced method for ultracold reactions that employ the quantum close-coupling method at short-range and the multichannel quantum defect theory at long-range, is demonstrated in accurately evaluating product state-resolved cross sections for D + H2 and H + D2 reactions.

Sulfated Titania-Silica Reinforced Nafion Nanocomposite Membranes for Proton Exchange Membrane Fuel Cells.

PubMed

Abu Sayeed, M D; Kim, Hee Jin; Gopalan, A I; Kim, Young Ho; Lee, Kwang-Pill; Choi, Sang-June

2015-09-01

Sulfated titania-silica (SO4(2-)-/TiO2-SiO2) composites were prepared by a sol-gel method with sulfate reaction and characterized by X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS). The nanometric diameter and geometry of the sulfated titania-silica (STS) was investigated by transmission electron microscopy (TEM). A small amount of the STS composite in the range of 0.5-3 wt% was then added as reinforcing into the Nafion membrane by water-assisted solution casting method to prepare STS reinforced Nafion nanocomposite membranes (STS-Nafion nanocomposite membranes). The additional functional groups, sulfate groups, of the nanocomposite membrane having more surface oxygenated groups enhanced the fuel cell membrane properties. The STS-Nafion nanocomposite membranes exhibited improved water uptake compared to that of neat Nafion membranes, whereas methanol uptake values were decreased dramatically improved thermal property of the prepared nanocomposite membranes were measured by thermogravimetric analysis (TGA). Furthermore, increased ion exchange capacity values were obtained by thermoacidic pretreatment of the nanocomposite membranes.

High-efficiency and air-stable P3HT-based polymer solar cells with a new non-fullerene acceptor

PubMed Central

Holliday, Sarah; Ashraf, Raja Shahid; Wadsworth, Andrew; Baran, Derya; Yousaf, Syeda Amber; Nielsen, Christian B.; Tan, Ching-Hong; Dimitrov, Stoichko D.; Shang, Zhengrong; Gasparini, Nicola; Alamoudi, Maha; Laquai, Frédéric; Brabec, Christoph J.; Salleo, Alberto; Durrant, James R.; McCulloch, Iain

2016-01-01

Solution-processed organic photovoltaics (OPV) offer the attractive prospect of low-cost, light-weight and environmentally benign solar energy production. The highest efficiency OPV at present use low-bandgap donor polymers, many of which suffer from problems with stability and synthetic scalability. They also rely on fullerene-based acceptors, which themselves have issues with cost, stability and limited spectral absorption. Here we present a new non-fullerene acceptor that has been specifically designed to give improved performance alongside the wide bandgap donor poly(3-hexylthiophene), a polymer with significantly better prospects for commercial OPV due to its relative scalability and stability. Thanks to the well-matched optoelectronic and morphological properties of these materials, efficiencies of 6.4% are achieved which is the highest reported for fullerene-free P3HT devices. In addition, dramatically improved air stability is demonstrated relative to other high-efficiency OPV, showing the excellent potential of this new material combination for future technological applications. PMID:27279376

Development of Thin-Walled Magnesium Alloy Extrusions for Improved Crash Performance Based Upon Texture Control

NASA Astrophysics Data System (ADS)

Williams, Bruce W.; Agnew, Sean R.; Klein, Robert W.; McKinley, Jonathan

Recent investigations suggest that it is possible to achieve dramatic modifications to both strength and ductility of magnesium alloys through a combination of alloying, grain refinement, and texture control. The current work explores the possibility of altering the texture in extruded thin-walled magnesium alloy tubes for improved ductility during axial crush in which energy is absorbed through progressive buckling. The texture evolution was predicted using the viscoplastic self-consistent (VPSC) crystal plasticity model, with strain path input from continuum-based finite element simulations of extrusion. A limited diversity of textures can be induced by altering the strain path through the extrusion die design. In some cases, such as for simple bar extrusion, the textures predicted can be connected with simple shape change. In other cases, a subtle influence of strain path involving shear-reverse-shear is predicted. The most promising textures predicted for a variety of strain paths are selected for subsequent experimental study.

Thermoelectrics. Dense dislocation arrays embedded in grain boundaries for high-performance bulk thermoelectrics.

PubMed

Kim, Sang Il; Lee, Kyu Hyoung; Mun, Hyeon A; Kim, Hyun Sik; Hwang, Sung Woo; Roh, Jong Wook; Yang, Dae Jin; Shin, Weon Ho; Li, Xiang Shu; Lee, Young Hee; Snyder, G Jeffrey; Kim, Sung Wng

2015-04-03

The widespread use of thermoelectric technology is constrained by a relatively low conversion efficiency of the bulk alloys, which is evaluated in terms of a dimensionless figure of merit (zT). The zT of bulk alloys can be improved by reducing lattice thermal conductivity through grain boundary and point-defect scattering, which target low- and high-frequency phonons. Dense dislocation arrays formed at low-energy grain boundaries by liquid-phase compaction in Bi(0.5)Sb(1.5)Te3 (bismuth antimony telluride) effectively scatter midfrequency phonons, leading to a substantially lower lattice thermal conductivity. Full-spectrum phonon scattering with minimal charge-carrier scattering dramatically improved the zT to 1.86 ± 0.15 at 320 kelvin (K). Further, a thermoelectric cooler confirmed the performance with a maximum temperature difference of 81 K, which is much higher than current commercial Peltier cooling devices. Copyright © 2015, American Association for the Advancement of Science.

Assessment of end-of-life design in solid-state lighting

NASA Astrophysics Data System (ADS)

Dzombak, Rachel; Padon, Jack; Salsbury, Josh; Dillon, Heather

2017-08-01

Consumers in the US market and across the globe are beginning to widely adopt light emitting diode (LED) lighting products while the technology continues to undergo significant changes. While LED products are evolving to consume less energy, they are also more complex than traditional lighting products with a higher number of parts and a larger number of electronic components. Enthusiasm around the efficiency and long expected life span of LED lighting products is valid, but research to optimize product characteristics and design is needed. This study seeks to address that gap by characterizing LED lighting products' suitability for end of life (EOL) recycling and disposal. The authors disassembled and assessed 17 different lighting products to understand how designs differ between brands and manufacture year. Products were evaluated based on six parameters to quantify the design. The analysis indicates that while the efficiency of LED products has improved dramatically in the recent past, product designers and manufacturers could incorporate design strategies to improve environmental performance of lighting products at end-of-life.

Fourier Transfrom Ion Cyclotron Resonance Mass Spectrometry at High Magnetic Field

NASA Astrophysics Data System (ADS)

Marshall, Alan G.

1998-03-01

At high magnetic field (9.4 tesla at NHMFL), Fourier transform ion cyclotron resonance mass spectrometry performance improves dramatically: mass resolving power, axialization efficiency, and scan speed (each proportional to B), maximum ion mass, dynamic range, ion trapping period, kinetic energy, and electron self-cooling rate for sympathetic cooling (each proportional to B^2), and ion coalescence tendency (proportional 1/B^2). These advantages may apply singly (e.g., unit mass resolution for proteins of >100,000 Da), or compound (e.g., 10-fold improvement in S/N ratio for 9.4 T vs. 6 T at the same resolving power). Examples range from direct determination of molecular formulas of diesel fuel components by accurate mass measurement (=B10.1 ppm) to protein structure and dynamics probed by H/D exchange. This work was supported by N.S.F. (CHE-93-22824; CHE-94-13008), N.I.H. (GM-31683), Florida State University, and the National High Magnetic Field Laboratory in Tallahassee, FL.

Electricity generation and nutrients removal from high-strength liquid manure by air-cathode microbial fuel cells.

PubMed

Lin, Hongjian; Wu, Xiao; Nelson, Chad; Miller, Curtis; Zhu, Jun

2016-01-01

Air-cathode microbial fuel cells (MFCs) are widely tested to recover electrical energy from waste streams containing organic matter. When high-strength wastewater, such as liquid animal manure, is used as a medium, inhibition on anode and cathode catalysts potentially impairs the effectiveness of MFC performance in power generation and pollutant removal. This study evaluated possible inhibitive effects of liquid swine manure components on MFC power generation, improved liquid manure-fed MFCs performance by pretreatment (dilution and selective adsorption), and modeled the kinetics of organic matter and nutrients removal kinetics. Parameters monitored included pH, conductivity, chemical oxygen demand (COD), volatile fatty acids (VFAs), total ammoniacal nitrogen (TAN), nitrite, nitrate, and phosphate concentrations. The removals of VFA and TAN were efficient, indicated by the short half-life times of 4.99 and 7.84 d, respectively. The mechanism for phosphate decrease was principally the salt precipitation on cathode, but the removal was incomplete after 42-d operation. MFC with an external resistor of 2.2 kΩ and fed with swine wastewater generated relatively small power (28.2 μW), energy efficiency (0.37%) and Coulombic efficiency (1.5%). Dilution of swine wastewater dramatically improved the power generation as the inhibitory effect was decreased. Zeolite and granular activated carbon were effective in the selective adsorption of ammonia or organic matter in swine wastewater, and so substantially improved the power generation, energy efficiency, and Coulombic efficiency. A smaller external resistor in the circuit was also observed to promote the organic matter degradation and thus to shorten the treatment time. Overall, air-cathode MFCs are promising for generating electrical power from livestock wastewater and meanwhile reducing the level of organic matter and nutrients.

Knotty: Efficient and Accurate Prediction of Complex RNA Pseudoknot Structures.

PubMed

Jabbari, Hosna; Wark, Ian; Montemagno, Carlo; Will, Sebastian

2018-06-01

The computational prediction of RNA secondary structure by free energy minimization has become an important tool in RNA research. However in practice, energy minimization is mostly limited to pseudoknot-free structures or rather simple pseudoknots, not covering many biologically important structures such as kissing hairpins. Algorithms capable of predicting sufficiently complex pseudoknots (for sequences of length n) used to have extreme complexities, e.g. Pknots (Rivas and Eddy, 1999) has O(n6) time and O(n4) space complexity. The algorithm CCJ (Chen et al., 2009) dramatically improves the asymptotic run time for predicting complex pseudoknots (handling almost all relevant pseudoknots, while being slightly less general than Pknots), but this came at the cost of large constant factors in space and time, which strongly limited its practical application (∼200 bases already require 256GB space). We present a CCJ-type algorithm, Knotty, that handles the same comprehensive pseudoknot class of structures as CCJ with improved space complexity of Θ(n3 + Z)-due to the applied technique of sparsification, the number of "candidates", Z, appears to grow significantly slower than n4 on our benchmark set (which include pseudoknotted RNAs up to 400 nucleotides). In terms of run time over this benchmark, Knotty clearly outperforms Pknots and the original CCJ implementation, CCJ 1.0; Knotty's space consumption fundamentally improves over CCJ 1.0, being on a par with the space-economic Pknots. By comparing to CCJ 2.0, our unsparsified Knotty variant, we demonstrate the isolated effect of sparsification. Moreover, Knotty employs the state-of-the-art energy model of "HotKnots DP09", which results in superior prediction accuracy over Pknots. Our software is available at https://github.com/HosnaJabbari/Knotty. will@tbi.unvie.ac.at. Supplementary data are available at Bioinformatics online.

Study of solids by use of nonthermalized positrons

NASA Astrophysics Data System (ADS)

Nielsen, Bent; Lynn, K. G.; Chen, Yen-C.

1986-10-01

We have measured the energy distribution of positrons reemitted from the surfaces of solids after being implanted at low energy. It is shown that this provides a unique possibility to study energy losses of a charged particle down to near-thermal energy. Such measurements are used to estimate the positron thermalization time in Al. A dramatic change in this energy distribution was observed after oxidation of the Al surface. We attribute this to the band gap of the oxide. Trapping of epithermal positrons with a remarkably high cross section was observed for both Al and Cu.

Nanoplasmonics: a frontier of photovoltaic solar cells

NASA Astrophysics Data System (ADS)

Gu, Min; Ouyang, Zi; Jia, Baohua; Stokes, Nicholas; Chen, Xi; Fahim, Narges; Li, Xiangping; Ventura, Michael James; Shi, Zhengrong

2012-12-01

Nanoplasmonics recently has emerged as a new frontier of photovoltaic research. Noble metal nanostructures that can concentrate and guide light have demonstrated great capability for dramatically improving the energy conversion efficiency of both laboratory and industrial solar cells, providing an innovative pathway potentially transforming the solar industry. However, to make the nanoplasmonic technology fully appreciated by the solar industry, key challenges need to be addressed; including the detrimental absorption of metals, broadband light trapping mechanisms, cost of plasmonic nanomaterials, simple and inexpensive fabrication and integration methods of the plasmonic nanostructures, which are scalable for full size manufacture. This article reviews the recent progress of plasmonic solar cells including the fundamental mechanisms, material fabrication, theoretical modelling and emerging directions with a distinct emphasis on solutions tackling the above-mentioned challenges for industrial relevant applications.

Palo Alto Research Center - Smart Embedded Network of Sensors with an Optical Readout

ScienceCinema

Raghavan, Ajay; Sahu, Saroj; Bringans, Ross; Johnson, Noble; Kiesel, Peter; Saha, Bhaskar

2018-05-18

PARC is developing new fiber optic sensors that would be embedded into batteries to monitor and measure key internal parameters during charge and discharge cycles. Two significant problems with today's best batteries are their lack of internal monitoring capabilities and their design oversizing. The lack of monitoring interferes with the ability to identify and manage performance or safety issues as they arise, which are presently managed by very conservative design oversizing and protection approaches that result in cost inefficiencies. PARC's design combines low-cost, embedded optical battery sensors and smart algorithms to overcome challenges faced by today's best battery management systems. These advanced fiber optic sensing technologies have the potential to dramatically improve the safety, performance, and life-time of energy storage systems.

Low-Damage Sputter Deposition on Graphene

NASA Astrophysics Data System (ADS)

Chen, Ching-Tzu; Casu, Emanuele; Gajek, Marcin; Raoux, Simone

2013-03-01

Despite its versatility and prevalence in the microelectronics industry, sputter deposition has seen very limited applications for graphene-based electronics. We have systematically investigated the sputtering induced graphene defects and identified the reflected high-energy neutrals of the sputtering gas as the primary cause of damage. In this talk, we introduce a novel sputtering technique that is shown to dramatically reduce bombardment of the fast neutrals and improve the structural integrity of the underlying graphene layer. We also demonstrate that sputter deposition and in-situ oxidation of 1 nm Al film at elevated temperatures yields homogeneous, fully covered oxide films with r.m.s. roughness much less than 1 monolayer, which shows the potential of using such technique for gate oxides, tunnel barriers, and multilayer fabrication in a wide range of graphene devices.

Rapid-fire improvement with short-cycle kaizen.

PubMed

Heard, E

1999-05-01

Continuous improvement is an attractive idea, but it is typically more myth than reality. SCK is no myth. It delivers dramatic improvements in traditional measures quickly. SCK accomplishes this via kaizens: rapid, repeated, time-compressed changes for the better in bite-sized chunks of the business.

Future energy system in environment, economy, and energy problems (2) various nuclear energy system evaluations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matsui, Kazuaki; Ujita, Hiroshi; Tashimo, Masanori

2006-07-01

Role and potentials of nuclear energy system in the energy options are discussed from the viewpoint of sustainable development with protecting from global warming by using the energy module structure of GRAPE model. They change and are affected dramatically by different sets of energy characteristics, nuclear behavior and energy policy even under the moderate set of presumptions. Introduction of thousands of reactors in the end of the century seems inevitable for better life and cleaner earth, but it will not come without efforts and cost. The analysis suggests the need of long term planning and R and D efforts undermore » the wisdom. (authors)« less

Home in the heat: Dramatic seasonal variation in home range of desert golden eagles informs management for renewable energy development

USGS Publications Warehouse

Braham, Melissa A.; Miller, Tricia A.; Duerr, Adam E.; Lanzone, Michael J.; Fesnock, Amy; LaPre, Larry; Driscoll, Daniel; Katzner, Todd E.

2015-01-01

Renewable energy is expanding quickly with sometimes dramatic impacts to species and ecosystems. To understand the degree to which sensitive species may be impacted by renewable energy projects, it is informative to know how much space individuals use and how that space may overlap with planned development. We used global positioning system–global system for mobile communications (GPS-GSM) telemetry to measure year-round movements of golden eagles (Aquila chrysaetos) from the Mojave Desert of California, USA. We estimated monthly space use with adaptive local convex hulls to identify the temporal and spatial scales at which eagles may encounter renewable energy projects in the Desert Renewable Energy Conservation Plan area. Mean size of home ranges was lowest and least variable from November through January and greatest in February–March and May–August. These monthly home range patterns coincided with seasonal variation in breeding ecology, habitat associations, and temperature. The expanded home ranges in hot summer months included movements to cooler, prey-dense, mountainous areas characterized by forest, grasslands, and scrublands. Breeding-season home ranges (October–May) included more lowland semi-desert and rock vegetation. Overlap of eagle home ranges and focus areas for renewable energy development was greatest when eagle home ranges were smallest, during the breeding season. Golden eagles in the Mojave Desert used more space and a wider range of habitat types than expected and renewable energy projects could affect a larger section of the regional population than was previously thought.

Crouch severity is a poor predictor of elevated oxygen consumption in cerebral palsy.

PubMed

Steele, Katherine M; Shuman, Benjamin R; Schwartz, Michael H

2017-07-26

Children with cerebral palsy (CP) expend more energy to walk compared to typically-developing peers. One of the most prevalent gait patterns among children with CP, crouch gait, is often singled out as especially exhausting. The dynamics of crouch gait increase external flexion moments and the demand on extensor muscles. This elevated demand is thought to dramatically increase energy expenditure. However, the impact of crouch severity on energy expenditure has not been investigated among children with CP. We evaluated oxygen consumption and gait kinematics for 573 children with bilateral CP. The average net nondimensional oxygen consumption during gait of the children with CP (0.18±0.06) was 2.9 times that of speed-matched typically-developing peers. Crouch severity was only modestly related to oxygen consumption, with measures of knee flexion angle during gait explaining only 5-20% of the variability in oxygen consumption. While knee moment and muscle activity were moderately to strongly correlated with crouch severity (r 2 =0.13-0.73), these variables were only weakly correlated with oxygen consumption (r 2 =0.02-0.04). Thus, although the dynamics of crouch gait increased muscle demand, these effects did not directly result in elevated energy expenditure. In clinical gait analysis, assumptions about an individual's energy expenditure should not be based upon kinematics or kinetics alone. Identifying patient-specific factors that contribute to increased energy expenditure may provide new pathways to improve gait for children with CP. Copyright © 2017 Elsevier Ltd. All rights reserved.

Synthesis of hierarchical porous δ-MnO2 nanoboxes as an efficient catalyst for rechargeable Li-O2 batteries

NASA Astrophysics Data System (ADS)

Zhang, Jian; Luan, Yanping; Lyu, Zhiyang; Wang, Liangjun; Xu, Leilei; Yuan, Kaidi; Pan, Feng; Lai, Min; Liu, Zhaolin; Chen, Wei

2015-09-01

A rechargeable lithium-oxygen (Li-O2) battery with a remarkably high theoretical energy storage capacity has attracted enormous research attention. However, the poor oxygen reduction and oxygen evolution reaction (ORR and OER) activities in discharge and charge processes cause low energy efficiency, poor electrolyte stability and short cycle life. This requires the development of efficient cathode catalysts to dramatically improve the Li-O2 battery performances. MnO2-based materials are recognized as efficient and low-cost catalysts for a Li-O2 battery cathode. Here, we report a controllable approach to synthesize hierarchical porous δ-MnO2 nanoboxes by using Prussian blue analogues as the precursors. The obtained products possess hierarchical pore size and an extremely large surface area (249.3 m2 g-1), which would favour oxygen transportation and provide more catalytically active sites to promote ORR and OER as the Li-O2 battery cathode. The battery shows enhanced discharge capacity (4368 mA h g-1@0.08 mA cm-2), reduced overpotential (270 mV), improved rate performance and excellent cycle stability (248 cycles@500 mA h g-1 and 112 cycles@1000 mA h g-1), in comparison with the battery with a VX-72 carbon cathode. The superb performance of the hierarchical porous δ-MnO2 nanoboxes, together with a convenient fabrication method, presents an alternative to develop advanced cathode catalysts for the Li-O2 battery.A rechargeable lithium-oxygen (Li-O2) battery with a remarkably high theoretical energy storage capacity has attracted enormous research attention. However, the poor oxygen reduction and oxygen evolution reaction (ORR and OER) activities in discharge and charge processes cause low energy efficiency, poor electrolyte stability and short cycle life. This requires the development of efficient cathode catalysts to dramatically improve the Li-O2 battery performances. MnO2-based materials are recognized as efficient and low-cost catalysts for a Li-O2 battery cathode. Here, we report a controllable approach to synthesize hierarchical porous δ-MnO2 nanoboxes by using Prussian blue analogues as the precursors. The obtained products possess hierarchical pore size and an extremely large surface area (249.3 m2 g-1), which would favour oxygen transportation and provide more catalytically active sites to promote ORR and OER as the Li-O2 battery cathode. The battery shows enhanced discharge capacity (4368 mA h g-1@0.08 mA cm-2), reduced overpotential (270 mV), improved rate performance and excellent cycle stability (248 cycles@500 mA h g-1 and 112 cycles@1000 mA h g-1), in comparison with the battery with a VX-72 carbon cathode. The superb performance of the hierarchical porous δ-MnO2 nanoboxes, together with a convenient fabrication method, presents an alternative to develop advanced cathode catalysts for the Li-O2 battery. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr02983j

Southeast Atmosphere Studies Workshop 2015

EPA Science Inventory

Concentrations of atmospheric trace species in the United States have changed dramatically over the past several decades in response to pollution control strategies, shifts in domestic energy policy, and economic development (and resulting emission changes) elsewhere in the world...

Enhanced Charge Extraction of Li-Doped TiO2 for Efficient Thermal-Evaporated Sb2S3 Thin Film Solar Cells

PubMed Central

Lan, Chunfeng; Luo, Jingting; Lan, Huabin; Fan, Bo; Peng, Huanxin; Zhao, Jun; Sun, Huibin; Zheng, Zhuanghao; Liang, Guangxing; Fan, Ping

2018-01-01

We provided a new method to improve the efficiency of Sb2S3 thin film solar cells. The TiO2 electron transport layers were doped by lithium to improve their charge extraction properties for the thermal-evaporated Sb2S3 solar cells. The Mott-Schottky curves suggested a change of energy band and faster charge transport in the Li-doped TiO2 films. Compared with the undoped TiO2, Li-doped mesoporous TiO2 dramatically improved the photo-voltaic performance of the thermal-evaporated Sb2S3 thin film solar cells, with the average power conversion efficiency (PCE) increasing from 1.79% to 4.03%, as well as the improved open-voltage (Voc), short-circuit current (Jsc) and fill factors. The best device based on Li-doped TiO2 achieved a power conversion efficiency up to 4.42% as well as a Voc of 0.645 V, which are the highest values among the reported thermal-evaporated Sb2S3 solar cells. This study showed that Li-doping on TiO2 can effectively enhance the charge extraction properties of electron transport layers, offering a new strategy to improve the efficiency of Sb2S3-based solar cells. PMID:29495612

Hurricanes, coral reefs and rainforests: resistance, ruin and recovery in the Caribbean

USGS Publications Warehouse

Lugo, Ariel E.; Rogers, Caroline S.; Nixon, Scott W.

2000-01-01

The coexistence of hurricanes, coral reefs, and rainforests in the Caribbean demonstrates that highly structured ecosystems with great diversity can flourish in spite of recurring exposure to intense destructive energy. Coral reefs develop in response to wave energy and resist hurricanes largely by virtue of their structural strength. Limited fetch also protects some reefs from fully developed hurricane waves. While storms may produce dramatic local reef damage, they appear to have little impact on the ability of coral reefs to provide food or habitat for fish and other animals. Rainforests experience an enormous increase in wind energy during hurricanes with dramatic structural changes in the vegetation. The resulting changes in forest microclimate are larger than those on reefs and the loss of fruit, leaves, cover, and microclimate has a great impact on animal populations. Recovery of many aspects of rainforest structure and function is rapid, though there may be long-term changes in species composition. While resistance and repair have maintained reefs and rainforests in the past, human impacts may threaten their ability to survive.

Correcting Inadequate Model Snow Process Descriptions Dramatically Improves Mountain Hydrology Simulations

NASA Astrophysics Data System (ADS)

Pomeroy, J. W.; Fang, X.

2014-12-01

The vast effort in hydrology devoted to parameter calibration as a means to improve model performance assumes that the models concerned are not fundamentally wrong. By focussing on finding optimal parameter sets and ascribing poor model performance to parameter or data uncertainty, these efforts may fail to consider the need to improve models with more intelligent descriptions of hydrological processes. To test this hypothesis, a flexible physically based hydrological model including a full suite of snow hydrology processes as well as warm season, hillslope and groundwater hydrology was applied to Marmot Creek Research Basin, Canadian Rocky Mountains where excellent driving meteorology and basin biophysical descriptions exist. Model parameters were set from values found in the basin or from similar environments; no parameters were calibrated. The model was tested against snow surveys and streamflow observations. The model used algorithms that describe snow redistribution, sublimation and forest canopy effects on snowmelt and evaporative processes that are rarely implemented in hydrological models. To investigate the contribution of these processes to model predictive capability, the model was "falsified" by deleting parameterisations for forest canopy snow mass and energy, blowing snow, intercepted rain evaporation, and sublimation. Model falsification by ignoring forest canopy processes contributed to a large increase in SWE errors for forested portions of the research basin with RMSE increasing from 19 to 55 mm and mean bias (MB) increasing from 0.004 to 0.62. In the alpine tundra portion, removing blowing processes resulted in an increase in model SWE MB from 0.04 to 2.55 on north-facing slopes and -0.006 to -0.48 on south-facing slopes. Eliminating these algorithms degraded streamflow prediction with the Nash Sutcliffe efficiency dropping from 0.58 to 0.22 and MB increasing from 0.01 to 0.09. These results show dramatic model improvements by including snow redistribution and melt processes associated with wind transport and forest canopies. As most hydrological models do not currently include these processes, it is suggested that modellers first improve the realism of model structures before trying to optimise what are inherently inadequate simulations of hydrology.

Maine PACE Program Final Technical Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fischer, Dana; Adamson, Joy M

The ARRA EECBG BetterBuilding helped augment the existing Home Energy Savings Programs (HESP) and incentives with financing through a subordinate lien PACE and HUD PowerSaver programs. The program was designed to document innovative techniques to dramatically increase the number of homes participating in weatherization programs in participating towns. Maine will support new energy efficiency retrofit pilots throughout the state, designed to motivate a large number of homeowners to invest in comprehensive home energy efficiency upgrades to bring real solutions to market.

Optimal estimates of free energies from multistate nonequilibrium work data.

PubMed

Maragakis, Paul; Spichty, Martin; Karplus, Martin

2006-03-17

We derive the optimal estimates of the free energies of an arbitrary number of thermodynamic states from nonequilibrium work measurements; the work data are collected from forward and reverse switching processes and obey a fluctuation theorem. The maximum likelihood formulation properly reweights all pathways contributing to a free energy difference and is directly applicable to simulations and experiments. We demonstrate dramatic gains in efficiency by combining the analysis with parallel tempering simulations for alchemical mutations of model amino acids.

Potential and Innovations in Rooftop Photovoltaics

NASA Astrophysics Data System (ADS)

Bierman, Ben

2011-11-01

Photovoltaic technology has reached a point where its cost and capability make it one of a handful of carbon-free sources of electrical energy that could meet a meaningful fraction of US energy demand. In this paper we will first compare Photovoltaics with several other carbon free energy technologies, then look at the economics of Solyndra's rooftop photovoltaic solution as an example of the current state of the art, as well as the market dynamics that have resulted in dramatically faster adoption in Germany vs. the United States.

Bile Routing Modification Reproduces Key Features of Gastric Bypass in Rat.

PubMed

Goncalves, Daisy; Barataud, Aude; De Vadder, Filipe; Vinera, Jennifer; Zitoun, Carine; Duchampt, Adeline; Mithieux, Gilles

2015-12-01

To evaluate the role of bile routing modification on the beneficial effects of gastric bypass surgery on glucose and energy metabolism. Gastric bypass surgery (GBP) promotes early improvements in glucose and energy homeostasis in obese diabetic patients. A suggested mechanism associates a decrease in hepatic glucose production to an enhanced intestinal gluconeogenesis. Moreover, plasma bile acids are elevated after GBP and bile acids are inhibitors of gluconeogenesis. In male Sprague-Dawley rats, we performed bile diversions from the bile duct to the midjejunum or the mid-ileum to match the modified bile delivery in the gut occurring in GBP. Body weight, food intake, glucose tolerance, insulin sensitivity, and food preference were analyzed. The expression of gluconeogenesis genes was evaluated in both the liver and the intestine. Bile diversions mimicking GBP promote an increase in plasma bile acids and a marked improvement in glucose control. Bile bioavailability modification is causal because a bile acid sequestrant suppresses the beneficial effects of bile diversions on glucose control. In agreement with the inhibitory role of bile acids on gluconeogenesis, bile diversions promote a blunting in hepatic glucose production, whereas intestinal gluconeogenesis is increased in the gut segments devoid of bile. In rats fed a high-fat-high-sucrose diet, bile diversions improve glucose control and dramatically decrease food intake because of an acquired disinterest in fatty food. This study shows that bile routing modification is a key mechanistic feature in the beneficial outcomes of GBP.

Bile Routing Modification Reproduces Key Features of Gastric Bypass in Rat

PubMed Central

Goncalves, Daisy; Barataud, Aude; De Vadder, Filipe; Vinera, Jennifer; Zitoun, Carine; Duchampt, Adeline; Mithieux, Gilles

2015-01-01

STRUCTURED ABSTRACT Objective To evaluate the role of bile routing modification on the beneficial effects of gastric bypass surgery on glucose and energy metabolism. Summary background data Gastric bypass surgery (GBP) promotes early improvements in glucose and energy homeostasis in obese diabetic patients. A suggested mechanism associates a decrease in hepatic glucose production (HGP) to an enhanced intestinal gluconeogenesis (IGN). Moreover, plasma bile acids are elevated after GBP and bile acids are inhibitors of gluconeogenesis. Methods In male Sprague-Dawley rats, we performed bile diversions from the bile duct to the mid-jejunum or the mid-ileum to match the modified bile delivery in the gut occurring in GBP. Body weight, food intake, glucose tolerance, insulin sensitivity and food preference were analyzed. The expression of gluconeogenesis genes was evaluated in both the liver and the intestine. Results Bile diversions mimicking GBP promote an increase in plasma bile acids and a marked improvement in glucose control. Bile bioavailability modification is causal since a bile acid sequestrant suppresses the beneficial effects of bile diversions on glucose control. In agreement with the inhibitory role of bile acids on gluconeogenesis, bile diversions promote a blunting in HGP, whereas IGN is increased in the gut segments devoid of bile. In rats fed a high fat-high sucrose diet, bile diversions improve glucose control and dramatically decrease food intake due to an acquired disinterest in fatty food. Conclusion This study shows that bile routing modification is a key mechanistic feature in the beneficial outcomes of GBP. PMID:25575265

Antimatter Production for Near-Term Propulsion Applications

NASA Technical Reports Server (NTRS)

Gerrish, Harold P.; Schmidt, George R.

1999-01-01

This presentation discusses the use and potential of power generated from Proton-Antiproton Annihilation. The problem is that there is not enough production of anti-protons, and that the production methods are inefficient. The cost for 1 gram of antiprotons is estimated at 62.5 trillion dollars. Applications which require large quantities (i.e., about 1 kg) will require dramatic improvements in the efficiency of the production of the antiprotons. However, applications which involve small quantities (i.e., 1 to 10 micrograms may be practical with a relative expansion of capacities. There are four "conventional" antimatter propulsion concepts which are: (1) the solid core, (2) the gas core, (3) the plasma core, and the (4) beam core. These are compared in terms of specific impulse, propulsive energy utilization and vehicle structure/propellant mass ratio. Antimatter-catalyzed fusion propulsion is also evaluated. The improvements outlined in the presentation to the Fermilab production, and other sites. capability would result in worldwide capacity of several micrograms per year, by the middle of the next decade. The conclusions drawn are: (1) the Conventional antimatter propulsion IS not practical due to large p-bar requirement; (2) Antimatter-catalyzed systems can be reasonably considered this "solves" energy cost problem by employing substantially smaller quantities; (3) With current infrastructure, cost for 1 microgram of p-bars is $62.5 million, but with near-term improvements cost should drop; (4) Milligram-scale facility would require a $15 billion investment, but could produce 1 mg, at $0.1/kW-hr, for $6.25 million.

Assessment of Orbital-Optimized MP2.5 for Thermochemistry and Kinetics: Dramatic Failures of Standard Perturbation Theory Approaches for Aromatic Bond Dissociation Energies and Barrier Heights of Radical Reactions.

PubMed

Soydaş, Emine; Bozkaya, Uğur

2015-04-14

An assessment of orbital-optimized MP2.5 (OMP2.5) [ Bozkaya, U.; Sherrill, C. D. J. Chem. Phys. 2014, 141, 204105 ] for thermochemistry and kinetics is presented. The OMP2.5 method is applied to closed- and open-shell reaction energies, barrier heights, and aromatic bond dissociation energies. The performance of OMP2.5 is compared with that of the MP2, OMP2, MP2.5, MP3, OMP3, CCSD, and CCSD(T) methods. For most of the test sets, the OMP2.5 method performs better than MP2.5 and CCSD, and provides accurate results. For barrier heights of radical reactions and aromatic bond dissociation energies OMP2.5-MP2.5, OMP2-MP2, and OMP3-MP3 differences become obvious. Especially, for aromatic bond dissociation energies, standard perturbation theory (MP) approaches dramatically fail, providing mean absolute errors (MAEs) of 22.5 (MP2), 17.7 (MP2.5), and 12.8 (MP3) kcal mol(-1), while the MAE values of the orbital-optimized counterparts are 2.7, 2.4, and 2.4 kcal mol(-1), respectively. Hence, there are 5-8-folds reductions in errors when optimized orbitals are employed. Our results demonstrate that standard MP approaches dramatically fail when the reference wave function suffers from the spin-contamination problem. On the other hand, the OMP2.5 method can reduce spin-contamination in the unrestricted Hartree-Fock (UHF) initial guess orbitals. For overall evaluation, we conclude that the OMP2.5 method is very helpful not only for challenging open-shell systems and transition-states but also for closed-shell molecules. Hence, one may prefer OMP2.5 over MP2.5 and CCSD as an O(N(6)) method, where N is the number of basis functions, for thermochemistry and kinetics. The cost of the OMP2.5 method is comparable with that of CCSD for energy computations. However, for analytic gradient computations, the OMP2.5 method is only half as expensive as CCSD.

Analysis of renewable energy sources and electric vehicle penetration into energy systems predominantly based on lignite

NASA Astrophysics Data System (ADS)

Dedinec, A.; Jovanovski, B.; Gajduk, A.; Markovska, N.; Kocarev, L.

2016-05-01

We consider an integration of renewable energy into transport and electricity sectors through vehicle to grid (V2G) technologies for an energy system that is predominantly based on lignite. The national energy system of Macedonia is modeled using EnergyPLAN which integrates energy for electricity, transport and heat, and includes hourly fluctuations in human needs and the environment. We show that electric-vehicles can provide the necessary storage enabling a fully renewable energy profile for Macedonia that can match the country's growing demand for energy. Furthermore, a large penetration of electric vehicles leads to a dramatic reduction of 47% of small particles and other air pollutants generated by car traffic in 2050.

Geothermal Systems of the Great Basin and U.S. Geological Survey Plans for a Regional Resource Assessment

USGS Publications Warehouse

Williams, C.F.

2002-01-01

Based on current projections, the United States faces the need to increase its electrical power generating capacity by 40% (approximately 300,000 Megawatts-electrical or MWe) over the next 20 years (Energy Information Administration, EIA - Department of Energy). A critical question for the near future is the extent to which geothermal resources can contribute to this increasing demand for electricity. Geothermal energy constitutes one of the nation's largest sources of renewable and environmentally benign electrical power, yet the installed capacity of 2860 MWe falls far short of estimated geothermal resources. This is particularly true for the Great Basin region of the western United States, which has an installed capacity of about 500 MWe, much lower than the 7500 MWe resource estimated by the U.S. Geological Survey (USGS) in the late 1970s. The reasons for the limited development of geothermal power are varied, but political, economic and technological developments suggest the time is ripe for a new assessment effort. Technologies for power production from geothermal systems and scientific understanding of geothermal resource occurrence have improved dramatically in recent years. The primary challenges facing geothermal resource studies are (1) understanding the thermal, chemical and mechanical processes that lead to the colocation of high temperatures and high permeabilities necessary for the formation of geothermal systems and (2) developing improved techniques for locating, characterizing and exploiting these systems. Starting in the fall of 2002, the USGS will begin work with institutions funded by the Department of Energy's (DOE) Geothermal Research Program to investigate the nature and extent of geothermal systems in the Great Basin and to produce an updated assessment of available geothermal resources.

Insulin oedema and treatment-induced neuropathy occurring in a 20-year-old patient with Type 1 diabetes commenced on an insulin pump.

PubMed

Rothacker, K M; Kaye, J

2014-01-01

Oedema may occur following initiation or intensification of insulin therapy in patients with Type 1 and Type 2 diabetes. Mild oedema is thought to be not uncommon, but under-reported, whilst generalized oedema with involvement of serous cavities has rarely been described. Multiple pathogenic mechanisms have been proposed, including insulin-induced sodium and water retention. Patients at greater risk for insulin oedema include those with poor glycaemic control. Dramatic improvement in glycaemic control is also associated with sensory and autonomic neuropathy. We describe a case of generalized oedema occurring in a 20-year-old, low body weight patient with Type 1 diabetes with poor glycaemic control 3 days following commencement of an insulin pump; blood sugars had dramatically improved with this treatment. Alternative causes for oedema were excluded. Oedema slowly improved with insulin dose reduction with higher blood sugar targets plus frusemide treatment. Subsequent to oedema resolution, the patient unfortunately developed generalized neuropathic pain, thought to be another manifestation of rapid improvement in glycaemic control. Caution should be taken when a patient with diabetes that is poorly controlled has an escalation in therapy that may dramatically improve their blood sugar levels; this includes the initiation of an insulin pump. Clinicians and patients should be aware of the potential risk of insulin oedema, treatment-induced neuropathy and worsening of diabetic retinopathy in the setting of rapid improvement in glycaemic control. © 2013 The Authors. Diabetic Medicine © 2013 Diabetes UK.

ADVANCED CERAMIC MATERIALS FOR NEXT-GENERATION NUCLEAR APPLICATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marra, J.

2010-09-29

Rising global energy demands coupled with increased environmental concerns point to one solution; they must reduce their dependence on fossil fuels that emit greenhouse gases. As the global community faces the challenge of maintaining sovereign nation security, reducing greenhouse gases, and addressing climate change nuclear power will play a significant and likely growing role. In the US, nuclear energy already provides approximately one-fifth of the electricity used to power factories, offices, homes, and schools with 104 operating nuclear power plants, located at 65 sites in 31 states. Additionally, 19 utilities have applied to the US Nuclear Regulatory Commission (NRC) formore » construction and operating licenses for 26 new reactors at 17 sites. This planned growth of nuclear power is occurring worldwide and has been termed the 'nuclear renaissance.' As major industrial nations craft their energy future, there are several important factors that must be considered about nuclear energy: (1) it has been proven over the last 40 years to be safe, reliable and affordable (good for Economic Security); (2) its technology and fuel can be domestically produced or obtained from allied nations (good for Energy Security); and (3) it is nearly free of greenhouse gas emissions (good for Environmental Security). Already an important part of worldwide energy security via electricity generation, nuclear energy can also potentially play an important role in industrial processes and supporting the nation's transportation sector. Coal-to-liquid processes, the generation of hydrogen and supporting the growing potential for a greatly increased electric transportation system (i.e. cars and trains) mean that nuclear energy could see dramatic growth in the near future as we seek to meet our growing demand for energy in cleaner, more secure ways. In order to address some of the prominent issues associated with nuclear power generation (i.e., high capital costs, waste management, and proliferation), the worldwide community is working to develop and deploy new nuclear energy systems and advanced fuel cycles. These new nuclear systems address the key challenges and include: (1) extracting the full energy value of the nuclear fuel; (2) creating waste solutions with improved long term safety; (3) minimizing the potential for the misuse of the technology and materials for weapons; (4) continually improving the safety of nuclear energy systems; and (5) keeping the cost of energy affordable.« less

Modeling and Simulation of HVAC Faulty Operations and Performance Degradation due to Maintenance Issues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Liping; Hong, Tianzhen

Almost half of the total energy used in the U.S. buildings is consumed by heating, ventilation and air conditionings (HVAC) according to EIA statistics. Among various driving factors to energy performance of building, operations and maintenance play a significant role. Many researches have been done to look at design efficiencies and operational controls for improving energy performance of buildings, but very few study the impacts of HVAC systems maintenance. Different practices of HVAC system maintenance can result in substantial differences in building energy use. If a piece of HVAC equipment is not well maintained, its performance will degrade. If sensorsmore » used for control purpose are not calibrated, not only building energy usage could be dramatically increased, but also mechanical systems may not be able to satisfy indoor thermal comfort. Properly maintained HVAC systems can operate efficiently, improve occupant comfort, and prolong equipment service life. In the paper, maintenance practices for HVAC systems are presented based on literature reviews and discussions with HVAC engineers, building operators, facility managers, and commissioning agents. We categorize the maintenance practices into three levels depending on the maintenance effort and coverage: 1) proactive, performance-monitored maintenance; 2) preventive, scheduled maintenance; and 3) reactive, unplanned or no maintenance. A sampled list of maintenance issues, including cooling tower fouling, boiler/chiller fouling, refrigerant over or under charge, temperature sensor offset, outdoor air damper leakage, outdoor air screen blockage, outdoor air damper stuck at fully open position, and dirty filters are investigated in this study using field survey data and detailed simulation models. The energy impacts of both individual maintenance issue and combined scenarios for an office building with central VAV systems and central plant were evaluated by EnergyPlus simulations using three approaches: 1) direct modeling with EnergyPlus, 2) using the energy management system feature of EnergyPlus, and 3) modifying EnergyPlus source code. The results demonstrated the importance of maintenance for HVAC systems on energy performance of buildings. The research is intended to provide a guideline to help practitioners and building operators to gain the knowledge of maintaining HVAC systems in efficient operations, and prioritize HVAC maintenance work plan. The paper also discusses challenges of modeling building maintenance issues using energy simulation programs.« less

Southeast Atmosphere Studies: learning from model-observation syntheses

EPA Science Inventory

Concentrations of atmospheric trace species in the United States have changed dramatically over the past several decades in response to pollution control strategies, shifts in domestic energy policy and economics, and economic development (and resulting emission changes) elsewher...

Profiling 1366 Technologies: One Year Later

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Mierlo, Frank; Sachs, Ely

2011-01-01

Last January, we took a look at how ARPA-E performer, 1366 Technologies is working to dramatically reduce the cost of solar energy. A year later, we revisited their headquarters in Lexington, MA to see the progress they've made.

Profiling 1366 Technologies: One Year Later

ScienceCinema

Van Mierlo, Frank; Sachs, Ely

2018-05-30

Last January, we took a look at how ARPA-E performer, 1366 Technologies is working to dramatically reduce the cost of solar energy. A year later, we revisited their headquarters in Lexington, MA to see the progress they've made.

Clinical Information Systems – From Yesterday to Tomorrow

PubMed Central

2016-01-01

Summary Objectives To review the history of clinical information systems over the past twenty-five years and project anticipated changes to those systems over the next twenty-five years. Methods Over 250 Medline references about clinical information systems, quality of patient care, and patient safety were reviewed. Books, Web resources, and the author’s personal experience with developing the HELP system were also used. Results There have been dramatic improvements in the use and acceptance of clinical computing systems and Electronic Health Records (EHRs), especially in the United States. Although there are still challenges with the implementation of such systems, the rate of progress has been remarkable. Over the next twenty-five years, there will remain many important opportunities and challenges. These opportunities include understanding complex clinical computing issues that must be studied, understood and optimized. Dramatic improvements in quality of care and patient safety must be anticipated as a result of the use of clinical information systems. These improvements will result from a closer involvement of clinical informaticians in the optimization of patient care processes. Conclusions Clinical information systems and computerized clinical decision support have made contributions to medicine in the past. Therefore, by using better medical knowledge, optimized clinical information systems, and computerized clinical decision, we will enable dramatic improvements in both the quality and safety of patient care in the next twenty-five years. PMID:27362589

Fossil Energy: Drivers and Challenges.

NASA Astrophysics Data System (ADS)

Friedmann, Julio

2007-04-01

Concerns about rapid economic growth, energy security, and global climate change have created a new landscape for fossil energy exploration, production, and utilization. Since 85% of primary energy supply comes from fossil fuels, and 85% of greenhouse gas emissions come from fossil fuel consumption, new and difficult technical and political challenges confront commercial, governmental, and public stakeholders. As such, concerns over climate change are explicitly weighed against security of international and domestic energy supplies, with economic premiums paid for either or both. Efficiency improvements, fuel conservation, and deployment of nuclear and renewable supplies will help both concerns, but are unlikely to offset growth in the coming decades. As such, new technologies and undertakings must both provide high quality fossil energy with minimal environmental impacts. The largest and most difficult of these undertakings is carbon management, wherein CO2 emissions are sequestered indefinitely at substantial incremental cost. Geological formations provide both high confidence and high capacity for CO2 storage, but present scientific and technical challenges. Oil and gas supply can be partially sustained and replaced through exploitation of unconventional fossil fuels such as tar-sands, methane hydrates, coal-to-liquids, and oil shales. These fuels provide enormous reserves that can be exploited at current costs, but generally require substantial energy to process. In most cases, the energy return on investment (EROI) is dropping, and unconventional fuels are generally more carbon intensive than conventional, presenting additional carbon management challenges. Ultimately, a large and sustained science and technology program akin to the Apollo project will be needed to address these concerns. Unfortunately, real funding in energy research has dropped dramatically (75%) in the past three decades, and novel designs in fission and fusion are not likely to provide any substantial offset in the next 30 years when they are most needed internationally.

Continuous Quality Improvement: A Roadmap for Rural School Improvement.

ERIC Educational Resources Information Center

Kilmer, Lloyd C.

A case study documented a continuous quality improvement approach to school improvement in a rural Nebraska high school over a 2-year period. Data gathered from surveys, portfolios, pilot results, and test scores indicated that the changes during the 2-year period were not dramatic, but significant and consistent with the Total Quality literature.…

Rectal cancer surgery: a brief history.

PubMed

Galler, Avi S; Petrelli, Nicholas J; Shakamuri, Shanthi P

2011-12-01

In the last 250 years, the treatment of rectal cancer has changed dramatically. Once considered an incurable disease, combined modality therapy has improved mortality from 100% to less than 4% for locally advanced rectal cancer. This dramatic reduction paralleled surgical techniques based on a growing understanding of anatomy and disease pathology. In order to understand modern treatment, it is necessary to recognize the achievements of preceding surgeons. Copyright © 2010 Elsevier Ltd. All rights reserved.

Dramatic reduction of culture time of Mycobacterium tuberculosis

NASA Astrophysics Data System (ADS)

Ghodbane, Ramzi; Raoult, Didier; Drancourt, Michel

2014-02-01

Mycobacterium tuberculosis culture, a critical technique for routine diagnosis of tuberculosis, takes more than two weeks. Here, step-by-step improvements in the protocol including a new medium, microaerophlic atmosphere or ascorbic-acid supplement and autofluorescence detection dramatically shortened this delay. In the best case, primary culture and rifampicin susceptibility testing were achieved in 72 hours when specimens were inoculated directly on the medium supplemented by antibiotic at the beginning of the culture.

Improvement of Energy Capacity with Vitamin C Treated Dual-Layered Graphene-Sulfur Cathodes in Lithium-Sulfur Batteries.

PubMed

Kim, Jin Won; Ocon, Joey D; Kim, Ho-Sung; Lee, Jaeyoung

2015-09-07

A graphene-based cathode design for lithium-sulfur batteries (LSB) that shows excellent electrochemical performance is proposed. The dual-layered cathode is composed of a sulfur active layer and a polysulfide absorption layer, and both layers are based on vitamin C treated graphene oxide at various degrees of reduction. By controlling the degree of reduction of graphene, the dual-layered cathode can increase sulfur utilization dramatically owing to the uniform formation of nanosized sulfur particles, the chemical bonding of dissolved polysulfides on the oxygen-rich sulfur active layer, and the physisorption of free polysulfides on the absorption layer. This approach enables a LSB with a high specific capacity of over 600 mAh gsulfur (-1) after 100 cycles even under a high current rate of 1C (1675 mA gsulfur (-1) ). An intriguing aspect of our work is the synthesis of a high-performance dual-layered cathode by a green chemistry method, which could be a promising approach to LSBs with high energy and power densities. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electrolyte and composition effects on the performances of asymmetric supercapacitors constructed with Mn3O4 nanoparticles-graphene nanocomposites

NASA Astrophysics Data System (ADS)

Xiao, Yuanhua; Cao, Yongbo; Gong, Yuyin; Zhang, Aiqin; Zhao, Jihong; Fang, Shaoming; Jia, Dianzeng; Li, Feng

2014-01-01

Nanocomposites of Mn3O4 nanoparticles and graphene (GR) nanosheets - Mn3O4@GR can be made by growing Mn3O4 nanoparticles directly on the surfaces of GR in solvothermal reactions. The asymmetric supercapacitors constructed with Mn3O4@GR as positive and activated carbon (AC) as negative electrodes, respectively, show highly enhanced performances in energy storage. It was found that the electrolytes employed in constructing electrodes of the devices can influence the performances of Mn3O4@GR supercapacitors dramatically. Compared to their energy density in KOH electrolyte, the devices exhibit improved charge storage performances in Na2SO4 electrolyte. Furthermore, the charge storage abilities of the devices are closely related to the amount of Mn3O4 nanoparticles loaded onto the surface of GR nanosheets. The performances of Mn3O4@GR//AC asymmetric supercapacitors can be optimized by carefully tailoring the composition of electrode materials and adjusting the electrolytes for making the devices.

Rechargeable Lithium-Air Batteries: Development of Ultra High Specific Energy Rechargeable Lithium-Air Batteries Based on Protected Lithium Metal Electrodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2010-07-01

BEEST Project: PolyPlus is developing the world’s first commercially available rechargeable lithium-air (Li-Air) battery. Li-Air batteries are better than the Li-Ion batteries used in most EVs today because they breathe in air from the atmosphere for use as an active material in the battery, which greatly decreases its weight. Li-Air batteries also store nearly 700% as much energy as traditional Li-Ion batteries. A lighter battery would improve the range of EVs dramatically. Polyplus is on track to making a critical breakthrough: the first manufacturable protective membrane between its lithium–based negative electrode and the reaction chamber where it reacts with oxygenmore » from the air. This gives the battery the unique ability to recharge by moving lithium in and out of the battery’s reaction chamber for storage until the battery needs to discharge once again. Until now, engineers had been unable to create the complex packaging and air-breathing components required to turn Li-Air batteries into rechargeable systems.« less

Chiral signatures in angle-resolved valence photoelectron spectroscopy of pure glycidol enantiomers.

PubMed

Garcia, Gustavo A; Nahon, Laurent; Harding, Chris J; Powis, Ivan

2008-03-28

Photoionization of the chiral molecule glycidol has been investigated in the valence region. Photoelectron circular dichroism (PECD) curves have been obtained at various photon energies by using circularly polarized VUV synchrotron radiation and a velocity map imaging technique to record angle-resolved photoelectron spectra (PES). The measured chiral asymmetries vary dramatically with the photon energy as well as with the ionized orbital, improving the effective orbital resolution of the PECD spectrum with respect to the PES. Typical asymmetry factors of 5% are observed, but the peak values measured range up to 15%. The experimental results are interpreted by continuum multiple scattering (CMS-Xalpha) calculations for several thermally accessible glycidol conformers. We find that a nearly quantitative agreement between theory and experiments can be achieved for the ionization of several molecular orbitals. Owing to the sensitivity of PECD to molecular conformation this allows us to identify the dominant conformer. The influence of intramolecular hydrogen bond orbital polarization is found to play a small yet significant role in determining the chiral asymmetry in the electron angular distributions.

Generation and control of sound bullets with a nonlinear acoustic lens.

PubMed

Spadoni, Alessandro; Daraio, Chiara

2010-04-20

Acoustic lenses are employed in a variety of applications, from biomedical imaging and surgery to defense systems and damage detection in materials. Focused acoustic signals, for example, enable ultrasonic transducers to image the interior of the human body. Currently however the performance of acoustic devices is limited by their linear operational envelope, which implies relatively inaccurate focusing and low focal power. Here we show a dramatic focusing effect and the generation of compact acoustic pulses (sound bullets) in solid and fluid media, with energies orders of magnitude greater than previously achievable. This focusing is made possible by a tunable, nonlinear acoustic lens, which consists of ordered arrays of granular chains. The amplitude, size, and location of the sound bullets can be controlled by varying the static precompression of the chains. Theory and numerical simulations demonstrate the focusing effect, and photoelasticity experiments corroborate it. Our nonlinear lens permits a qualitatively new way of generating high-energy acoustic pulses, which may improve imaging capabilities through increased accuracy and signal-to-noise ratios and may lead to more effective nonintrusive scalpels, for example, for cancer treatment.

Generation and control of sound bullets with a nonlinear acoustic lens

PubMed Central

Spadoni, Alessandro; Daraio, Chiara

2010-01-01

Acoustic lenses are employed in a variety of applications, from biomedical imaging and surgery to defense systems and damage detection in materials. Focused acoustic signals, for example, enable ultrasonic transducers to image the interior of the human body. Currently however the performance of acoustic devices is limited by their linear operational envelope, which implies relatively inaccurate focusing and low focal power. Here we show a dramatic focusing effect and the generation of compact acoustic pulses (sound bullets) in solid and fluid media, with energies orders of magnitude greater than previously achievable. This focusing is made possible by a tunable, nonlinear acoustic lens, which consists of ordered arrays of granular chains. The amplitude, size, and location of the sound bullets can be controlled by varying the static precompression of the chains. Theory and numerical simulations demonstrate the focusing effect, and photoelasticity experiments corroborate it. Our nonlinear lens permits a qualitatively new way of generating high-energy acoustic pulses, which may improve imaging capabilities through increased accuracy and signal-to-noise ratios and may lead to more effective nonintrusive scalpels, for example, for cancer treatment. PMID:20368461

Wind for Schools: Developing Educational Programs to Train a New Workforce and the Next Generation of Wind Energy Experts (Poster)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flowers, L.; Baring-Gould, I.

2010-04-01

As the United States dramatically expands wind energy deployment, the industry is challenged with developing a skilled workforce and addressing public resistance. Wind Powering America's Wind for Schools project addresses these issues by: Developing Wind Application Centers (WACs) at universities; installing small wind turbines at community "host" schools; and implementing teacher training with interactive curricula at each host school.

Intravenous immunoglobulin therapy leading to dramatic improvement in a patient with systemic juvenile idiopathic arthritis and severe pericarditis resistant to steroid pulse therapy.

PubMed

Aizawa-Yashiro, Tomomi; Oki, Eishin; Tsuruga, Kazushi; Nakahata, Tohru; Ito, Etsuro; Tanaka, Hiroshi

2012-05-01

A 7-year-old Japanese boy with a 4-month history of systemic juvenile idiopathic arthritis (s-JIA) experienced disease flare with spiking fever, exanthema and arthralgia. He then developed progressive dyspnea due to severe pericarditis, and proinflammatory hypercytokinemia was suspected. Methylprednisolone pulse therapy was ineffective and echocardiography showed massive pericardial effusion had persisted. Alternatively, subsequent intravenous immunoglobulin (IVIG) therapy resulted in dramatic resolution of the pericardial effusion, and his general condition significantly improved within a few days. This case report may lend further support the use of IVIG for selected patients with s-JIA and severe pericarditis.

Design of Refractory Linings for Balanced Energy Efficiency, Uptime, and Capacity in Lime Kilns

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gorog, John Peter; Hemrick, James Gordon; Walker, Harold

2014-01-01

The rotary kilns used by the pulp and paper industry to regenerate lime in the Kraft process are very energy intensive. Throughout the 90 s, in response to increasing fuel prices, the industry used back up insulation in conjunction with the high alumina brick used to line the burning zones of their kilns. While this improved energy efficiency, the practice of installing insulating brick behind the working lining increased the inner wall temperatures. In the worst case, due to the increased temperatures, rapid brick failures occurred causing unscheduled outages and expensive repairs. Despite these issues, for the most part, themore » industry continued to use insulating refractory linings in that the energy savings were large enough to offset any increase in the cost of maintaining the refractory lining. Due to the dramatic decline in the price of natural gas in some areas combined with mounting pressures to increasing production of existing assets, over the last decade, many mills are focusing more on increasing the uptime of their kilns as opposed to energy savings. To this end, a growing number of mills are using basic (magnesia based) brick instead of high alumina brick to line the burning zone of the kiln since the lime mud does not react with these bricks at the operating temperatures of the burning zone of the kiln. In the extreme case, a few mills have chosen to install basic brick in the front end of the kiln running a length equivalent to 10 diameters. While the use of basic brick can increase the uptime of the kiln and reduce the cost to maintain the refractory lining, it does dramatically increase the heat losses resulting from the increased operating temperatures of the shell. Also, over long periods of time operating at these high temperatures, damage can occur in the shell. There are tradeoffs between energy efficiency, capacity and uptime. When fuel prices are very high, it makes sense to insulate the lining. When fuel prices are lower, trading some thermal efficiency for increased uptime and capacity seems reasonable. This paper considers a number of refractory linings in an effort to develop optimized operating strategies that balance these factors. In addition to considering a range of refractory materials, the paper examines other factors such as the chain area, discharge dams and other operating variables that impact the service life of the refractory lining. The paper provides recommendations that will help mill personnel develop a strategy to select a refractory lining that is optimized for their specific situation.« less

A case of organic brain syndrome following head injury successfully treated with carbamazepine.

PubMed

Bouvy, P F; van de Wetering, B J; Meerwaldt, J D; Bruijn, J B

1988-03-01

A case of organic brain syndrome occurring in relation to psychological stress 2 years after a severe head injury is described. Treatment with haloperidol resulted only in slight improvement. A dramatic improvement was achieved with carbamazepine.

Building a sustainable GIS framework for supporting a tribal transportation problem.

DOT National Transportation Integrated Search

2017-03-01

Due to the recent oil boom, the Fort Berthold Reservation has experienced a dramatic increase in highway and local traffic. To support energy transportation and provide safe roads, the reservation needs cost-efficient and effective transportation pla...

Connected vehicle applications for adaptive overhead lighting (on-demand lighting) : final research report.

DOT National Transportation Integrated Search

2016-07-01

The Virginia Tech Transportation Institute (VTTI) has developed an on-demand roadway lighting : system and has tested the systems effect on driver visual performance. On-demand roadway : lighting can dramatically reduce energy usage while maintain...

Lessons from the war on dietary fat.

PubMed

Walker, Thomas B; Parker, Mary Jo

2014-01-01

Conventional dietary guidelines put forth by health care institutions and providers for the past 40 years have stressed the importance of reducing the amount of dietary fat consumed. Such a diet is purported to mitigate metabolic risk factors and optimize the ability to achieve or maintain a healthy body weight. However, over the past 35 years obesity rates in the United States have risen dramatically though the level of dietary fat consumed by U.S. adults has fallen. This review examines the potential reasons for this paradox. Various meta-analyses, controlled trials, and cohort studies have demonstrated that reducing dietary fat intake provides for very little weight loss unless accompanied by equal or greater reductions in total energy intake. Due to both psychological (e.g., the tendency for people to eat more of what they consider low fat) and physiological (e.g., the low satiety that accompanies carbohydrate intake) factors, reducing total caloric intake while simultaneously reducing fat intake is a difficult challenge. Further, reductions in total carbohydrate intake, increases in protein intake, and adoption of a Mediterranean diet seem to be more effective in inducing weight loss than reductions in fat intake. Traditional claims that simply reducing dietary fat will improve metabolic risk factors are also not borne out by research. There is some evidence that replacing dietary saturated fat with unsaturated fat may improve metabolic risk factors, but that research is not conclusive. • Over the past 40 years, Americans have decreased the percentage of calories they get from dietary fat while rates of overweight and obesity have risen dramatically. • It appears that a decrease in total dietary fat in ad libitum diets may induce a very small decrease in body weight. • Evidence suggests that reductions in total dietary fat intake often occur in conjunction with an increase in total caloric intake. • It seems reasonable to conclude that guiding the public to simply reduce dietary fat intake is an ineffective method to mitigate the rise in obesity and improve public health.

Benchmarking the Bethe–Salpeter Formalism on a Standard Organic Molecular Set

PubMed Central

2015-01-01

We perform benchmark calculations of the Bethe–Salpeter vertical excitation energies for the set of 28 molecules constituting the well-known Thiel’s set, complemented by a series of small molecules representative of the dye chemistry field. We show that Bethe–Salpeter calculations based on a molecular orbital energy spectrum obtained with non-self-consistent G0W0 calculations starting from semilocal DFT functionals dramatically underestimate the transition energies. Starting from the popular PBE0 hybrid functional significantly improves the results even though this leads to an average −0.59 eV redshift compared to reference calculations for Thiel’s set. It is shown, however, that a simple self-consistent scheme at the GW level, with an update of the quasiparticle energies, not only leads to a much better agreement with reference values, but also significantly reduces the impact of the starting DFT functional. On average, the Bethe–Salpeter scheme based on self-consistent GW calculations comes close to the best time-dependent DFT calculations with the PBE0 functional with a 0.98 correlation coefficient and a 0.18 (0.25) eV mean absolute deviation compared to TD-PBE0 (theoretical best estimates) with a tendency to be red-shifted. We also observe that TD-DFT and the standard adiabatic Bethe–Salpeter implementation may differ significantly for states implying a large multiple excitation character. PMID:26207104

One-point fluctuation analysis of the high-energy neutrino sky

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feyereisen, Michael R.; Ando, Shin'ichiro; Tamborra, Irene, E-mail: m.r.feyereisen@uva.nl, E-mail: tamborra@nbi.ku.dk, E-mail: s.ando@uva.nl

2017-03-01

We perform the first one-point fluctuation analysis of the high-energy neutrino sky. This method reveals itself to be especially suited to contemporary neutrino data, as it allows to study the properties of the astrophysical components of the high-energy flux detected by the IceCube telescope, even with low statistics and in the absence of point source detection. Besides the veto-passing atmospheric foregrounds, we adopt a simple model of the high-energy neutrino background by assuming two main extra-galactic components: star-forming galaxies and blazars. By leveraging multi-wavelength data from Herschel and Fermi , we predict the spectral and anisotropic probability distributions for theirmore » expected neutrino counts in IceCube. We find that star-forming galaxies are likely to remain a diffuse background due to the poor angular resolution of IceCube, and we determine an upper limit on the number of shower events that can reasonably be associated to blazars. We also find that upper limits on the contribution of blazars to the measured flux are unfavourably affected by the skewness of the blazar flux distribution. One-point event clustering and likelihood analyses of the IceCube HESE data suggest that this method has the potential to dramatically improve over more conventional model-based analyses, especially for the next generation of neutrino telescopes.« less

Opportunities for the power industry in South Africa

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lynch, R.W.; Pinkney, C.; Feld, L.

1996-11-01

South Africa is a country in the midst of transformation. Political changes within the country, and the ensuing empowerment of the black majority, have created a situation where dramatic improvements are needed in the country`s infrastructure in order to enable it to meet the needs of all its people over the coming decades. Largely as a result of the international embargo placed on South Africa during the apartheid era, the South African government became heavily involved in the country`s energy sector. This involvement included development of a synfuels program, price controls in the oil sector, monopolies in both upstream andmore » downstream oil sectors, and a strong centralized electric power company. In 1994, South Africa became the eleventh member of the Southern Africa Development Community (SADC), an organization which was established in 1980 to synchronize development plans for its member countries. SADC is presently working to formulate a regional energy development plan, and coordinate technical information exchanges and joint research needs. Each of the SADC nations have also begun to develop their regional electricity grids and other parts of their energy infrastructure to plan for the growing needs of the 500 million people who live in sub-Saharan Africa. South Africa, in particular, must make significant changes in each of its energy sectors in the near future, to keep up with its growing energy requirements. These changes translate to opportunity for the US Power Industry.« less

The preparation of 3,5-dihydroxy-4-isopropylstilbene nanoemulsion and in vitro release

PubMed Central

Zhang, Yue; Gao, Jungang; Zheng, Hetang; Zhang, Ran; Han, Yucui

2011-01-01

We have reported a novel procedure to prepare 3,5-dihydroxy-4-isopropylstilbene (DHPS) nanoemulsion, using a low-energy emulsification method. Based on the phase diagram, the optimum prescription of nanoemulsion preparation was screened. With polyoxyethylenated castor oil (EL-40) as the surfactant, ethanol as the co-surfactant, and isopropyl myristate (IPM) as the oil phase, the DHPS nanoemulsion was obtained with a transparent appearance, little viscosity, and spherically uniform distribution verified by transmission electron microscopy and laser scattering analyzer. The nanoemulsion was also determined by FT-Raman spectroscopy. The DHPS nanoemulsion demonstrated good stability and stable physical and chemical properties. The nanoemulsion dramatically improved the transdermal release of DHPS (from 8.02 μg · cm−2 to 273.15 μg · cm−2) and could become a favorable new dosage form for DHPS. PMID:21674020

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ulvestad, Andrew; Sasikumar, Kiran; Kim, Jong Woo

Multielectron transfer processes are crucially important in energy and biological science but require favorable catalysts to achieve fast kinetics. Nanostructuring catalysts can dramatically improve their properties, which can be difficult to understand due to strain- and size-dependent thermodynamics, the influence of defects, and substrate-dependent activities. Here, we report three-dimensional (3D) imaging of single gold nanoparticles during catalysis of ascorbic acid decomposition using Bragg coherent diffractive imaging (BCDI). Local strains were measured in single nanoparticles and modeled using reactive molecular dynamics (RMD) simulations and finite element analysis (FEA) simulations. RMD reveals the pathway for local strain generation in the gold lattice:more » chemisorption of hydroxyl ions. FEA reveals that the RMD results are transferable to the nanocrystal sizes studied in the experiment. Our study probes the strain-activity connection and opens a powerful avenue for theoretical and experimental studies of nanocrystal catalysis.« less

Precision electroweak physics at LEP

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mannelli, M.

1994-12-01

Copious event statistics, a precise understanding of the LEP energy scale, and a favorable experimental situation at the Z{sup 0} resonance have allowed the LEP experiments to provide both dramatic confirmation of the Standard Model of strong and electroweak interactions and to place substantially improved constraints on the parameters of the model. The author concentrates on those measurements relevant to the electroweak sector. It will be seen that the precision of these measurements probes sensitively the structure of the Standard Model at the one-loop level, where the calculation of the observables measured at LEP is affected by the value chosenmore » for the top quark mass. One finds that the LEP measurements are consistent with the Standard Model, but only if the mass of the top quark is measured to be within a restricted range of about 20 GeV.« less

Strategies toward High Performance Organic Photovoltaic Cell: Material and Process

NASA Astrophysics Data System (ADS)

Kim, Bong Gi

The power conversion efficiency of organic photovoltaic (OPV) cells has been rapidly improved during the last few years and currently reaches around 10 %. The performance is evenly governed by absorption, exciton diffusion, exciton dissociation, carrier transfer, and collection efficiencies. Establishing a better understanding of OPV device physics combined with the development of new materials for each executive step contributes to this dramatic improvement. This dissertation focuses mainly on material design and development to correlate the intrinsic properties of organic semiconductors and the OPV performance. The introductory Chapter 1 briefly reviews the motivation of OPV research, its working mechanism, and representative organic materials for OPV application. Chapter 2 discusses the modulation of conjugated polymer's (CP's) absorption behavior and an efficient semi-empirical approach to predict CP's energy levels from its constituent monomers' HOMO/LUMO values. A strong acceptor lowered both the HOMO and LUMO levels of the CP, but the LUMO dropped more rapidly which ultimately produced a narrowed band-gap in the electron donating/accepting alternating copolymer system. In addition, the energy level difference between the CP and the constituent monomers converged to a constant value, providing an energy level prediction tool. Chapter 3 illustrates the systematic investigation on the relationship between the molecular structure of an energy harvesting organic dye and the exciton dissociation efficiency. The study showed that the quantum yield decreased as the exciton binding energy increases, and dipole moment direction should be properly oriented in the dye framework in order to improve photo-current generation when used in a dye sensitized photovoltaic device. Chapter 4 demonstrates the ultrasonic-assisted self-assembly of CPs in solution, rapidly and efficiently. Ultrasonication combined with dipolar media accelerated CP's aggregation, and the effect of CP's aggregation on the enhancement of OPV performance by promoting photo-current generation and increasing carrier mobility was systematically investigated. The correlation between the chemical structure of a CP and it aggregation behavior is further described in Chapter 5. To promote CP aggregate, a planar chain conformation was advantageous and CP aggregation improved hole mobility in the OPV device. However, thermally induced CP aggregates caused strong charge recombination, resulting in open circuit voltage drop. In Chapter 6, a novel polymer design principle to enable directed CP alignment is discussed. Regulating chain planarity and preventing massive crystallization of CP achieved by the developed molecular design principle allowed directed CP alignment under small shear flow.

Teacher Evaluation: Principals' Insights and Suggestions for Improvement

ERIC Educational Resources Information Center

Kersten, Thomas A.; Israel, Marla S.

2005-01-01

In the twenty-first century, school improvement is the focal point for educational leadership, in which the school building administrator is recognized as the catalyst for this necessary improvement. Within the area of teacher evaluation, the evaluation tools, along with the amount of time, format, and feedback, have changed dramatically from the…

A survey of pulse shape options for a revised plastic ablator ignition design

NASA Astrophysics Data System (ADS)

Clark, Daniel; Eder, David; Haan, Steven; Hinkel, Denise; Jones, Ogden; Marinak, Michael; Milovich, Jose; Peterson, Jayson; Robey, Harold; Salmonson, Jay; Smalyuk, Vladimir; Weber, Christopher

2014-10-01

Recent experimental results using the ``high foot'' pulse shape on the National Ignition Facility (NIF) have shown encouraging progress compared to earlier ``low foot'' experiments. These results strongly suggest that controlling ablation front instability growth can dramatically improve implosion performance, even in the presence of persistent, large, low-mode distortions. In parallel, Hydro. Growth Radiography experiments have so far validated the techniques used for modeling ablation front growth in NIF experiments. It is timely then to combine these two results and ask how current ignition pulse shapes could be modified so as to improve implosion performance, namely fuel compressibility, while maintaining the stability properties demonstrated with the high foot. This talk presents a survey of pulse shapes intermediate between the low and high foot extremes in search of a more optimal design. From the database of pulse shapes surveyed, a higher picket version of the original low foot pulse shape shows the most promise for improved compression without loss of stability. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Insights into the Functions of M-T Hook Structure in HIV Fusion Inhibitor Using Molecular Modeling.

PubMed

Tan, Jianjun; Yuan, Hongling; Li, Chunhua; Zhang, Xiaoyi; Wang, Cunxin

2016-04-01

HIV-1 membrane fusion plays an important role in the process that HIV-1 entries host cells. As a treatment strategy targeting HIV-1 entry process, fusion inhibitors have been proposed. Nevertheless, development of a short peptide possessing high anti-HIV potency is considered a daunting challenge. He et al. found that two residues, Met626 and Thr627, located the upstream of the C-terminal heptad repeat of the gp41, formed a unique hook-like structure (M-T hook) that can dramatically improve the binding stability and anti-HIV activity of the inhibitors. In this work, we explored the molecular mechanism why M-T hook structure could improve the anti-HIV activity of inhibitors. Firstly, molecular dynamic simulation was used to obtain information on the time evolution between gp41 and ligands. Secondly, based on the simulations, molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) and molecular mechanics Generalized Born surface area (MM-GBSA) methods were used to calculate the binding free energies. The binding free energy of the ligand with M-T hook was considerably higher than the other without M-T. Further studies showed that the hydrophobic interactions made the dominant contribution to the binding free energy. The numbers of Hydrogen bonds between gp41 and the ligand with M-T hook structure were more than the other. These findings should provide insights into the inhibition mechanism of the short peptide fusion inhibitors and be useful for the rational design of novel fusion inhibitors in the future. Copyright © 2016 Elsevier Ltd. All rights reserved.

Vibrational energy transfer dynamics in ruthenium polypyridine transition metal complexes.

PubMed

Fedoseeva, Marina; Delor, Milan; Parker, Simon C; Sazanovich, Igor V; Towrie, Michael; Parker, Anthony W; Weinstein, Julia A

2015-01-21

Understanding the dynamics of the initial stages of vibrational energy transfer in transition metal complexes is a challenging fundamental question which is also of crucial importance for many applications, such as improving the performance of solar devices or photocatalysis. The present study investigates vibrational energy transport in the ground and the electronic excited state of Ru(4,4'-(COOEt)2-2,2-bpy)2(NCS)2, a close relative of the efficient "N3" dye used in dye-sensitized solar cells. Using the emerging technique of ultrafast two-dimensional infrared spectroscopy, we show that, similarly to other transition-metal complexes, the central Ru heavy atom acts as a "bottleneck" making the energy transfer from small ligands with high energy vibrational stretching frequencies less favorable and thereby affecting the efficiency of vibrational energy flow in the complex. Comparison of the vibrational relaxation times in the electronic ground and excited state of Ru(4,4'-(COOEt)2-2,2-bpy)2(NCS)2 shows that it is dramatically faster in the latter. We propose to explain this observation by the intramolecular electrostatic interactions between the thiocyanate group and partially oxidised Ru metal center, which increase the degree of vibrational coupling between CN and Ru-N modes in the excited state thus reducing structural and thermodynamic barriers that slow down vibrational relaxation and energy transport in the electronic ground state. As a very similar behavior was earlier observed in another transition-metal complex, Re(4,4'-(COOEt)2-2,2'-bpy)(CO)3Cl, we suggest that this effect in vibrational energy dynamics might be common for transition-metal complexes with heavy central atoms.

Achieving Dramatic School Improvement: An Exploratory Study. A Cross-Site Analysis from the Evaluation of Comprehensive School Reform Program Implementation and Outcomes Study

ERIC Educational Resources Information Center

Aladjem, Daniel K.; Birman, Beatrice F.; Orland, Martin; Harr-Robins, Jenifer; Heredia, Alberto; Parrish, Thomas B.; Ruffini, Stephen J.

2010-01-01

This exploratory study describes approaches to improving schools through retrospective, in-depth qualitative case studies. To select schools to be examined, the authors sought to identify Comprehensive School Reform (CSR) schools demonstrating two distinctive patterns of improved student achievement between 2000 and 2005, rapid-improvement (i.e.,…

Physics of Quantum Structures in Photovoltaic Devices

NASA Technical Reports Server (NTRS)

Raffaelle, Ryne P.; Andersen, John D.

2005-01-01

There has been considerable activity recently regarding the possibilities of using various nanostructures and nanomaterials to improve photovoltaic conversion of solar energy. Recent theoretical results indicate that dramatic improvements in device efficiency may be attainable through the use of three-dimensional arrays of zero-dimensional conductors (i.e., quantum dots) in an ordinary p-i-n solar cell structure. Quantum dots and other nanostructured materials may also prove to have some benefits in terms of temperature coefficients and radiation degradation associated with space solar cells. Two-dimensional semiconductor superlattices have already demonstrated some advantages in this regard. It has also recently been demonstrated that semiconducting quantum dots can also be used to improve conversion efficiencies in polymeric thin film solar cells. Improvement in thin film cells utilizing conjugated polymers has also be achieved through the use of one-dimensional quantum structures such as carbon nanotubes. It is believed that carbon nanotubes may contribute to both the disassociation as well as the carrier transport in the conjugated polymers used in certain thin film photovoltaic cells. In this paper we will review the underlying physics governing some of the new photovoltaic nanostructures being pursued, as well as the the current methods being employed to produce III-V, II-VI, and even chalcopyrite-based nanomaterials and nanostructures for solar cells.

Nicotinamide mononucleotide inhibits post-ischemic NAD(+) degradation and dramatically ameliorates brain damage following global cerebral ischemia.

PubMed

Park, Ji H; Long, Aaron; Owens, Katrina; Kristian, Tibor

2016-11-01

Nicotinamide adenine dinucleotide (NAD(+)) is an essential cofactor for multiple cellular metabolic reactions and has a central role in energy production. Brain ischemia depletes NAD(+) pools leading to bioenergetics failure and cell death. Nicotinamide mononucleotide (NMN) is utilized by the NAD(+) salvage pathway enzyme, nicotinamide adenylyltransferase (Nmnat) to generate NAD(+). Therefore, we examined whether NMN could protect against ischemic brain damage. Mice were subjected to transient forebrain ischemia and treated with NMN or vehicle at the start of reperfusion or 30min after the ischemic insult. At 2, 4, and 24h of recovery, the proteins poly-ADP-ribosylation (PAR), hippocampal NAD(+) levels, and expression levels of NAD(+) salvage pathway enzymes were determined. Furthermore, animal's neurologic outcome and hippocampal CA1 neuronal death was assessed after six days of reperfusion. NMN (62.5mg/kg) dramatically ameliorated the hippocampal CA1 injury and significantly improved the neurological outcome. Additionally, the post-ischemic NMN treatment prevented the increase in PAR formation and NAD(+) catabolism. Since the NMN administration did not affect animal's temperature, blood gases or regional cerebral blood flow during recovery, the protective effect was not a result of altered reperfusion conditions. These data suggest that administration of NMN at a proper dosage has a strong protective effect against ischemic brain injury. Published by Elsevier Inc.

Treatment with teriparatide in a patient with pregnancy-associated osteoporosis.

PubMed

Hellmeyer, Lars; Boekhoff, Jelena; Hadji, Peyman

2010-10-01

The decrease of BMD during a physiological pregnancy can in rare cases be intensified and lead to dramatic microarchitectural changes, which causes an increase incidence of fractures, preferably at the spine. This dramatic clinical picture is called pregnancy-associated osteoporosis. We present the case of a 40-year-old woman (gravida IV, para II) with acute back pain right after delivery due to four fractures of the spine. The diagnosis was confirmed by dual-energy X-ray absorptiometry measurement result (T-score -4.1 SD (0.598 g/cm(2)) at the lumbar spine (L1-L4), T-score -1.5 SD (0.759 g/cm(2)) at the total hip). Due to the severity of symptoms, a therapy with teriparatide (20 mg daily) was started for a period of 18 months. After end of therapy, the T-score had significantly increased at the lumbar spine as well as at the hip (T-score of -2.1 (0.813 g/cm(2)) and -0.6 (0.864 g/cm(2)), respectively. The relative increase of BMD at the spine and total hip was 36% and 13.8%, respectively. Our report demonstrates the successful use of teriparatide underlined by the increase of bone mineral density and the improvement of clinical symptoms in a case of severe pregnancy-associated osteoporosis for the first time.

Assessing global radiative forcing due to regional emissions of tropospheric ozone precursors: a step towards climate credit for ozone reductions

NASA Astrophysics Data System (ADS)

Mauzerall, D. L.; Naik, V.; Horowitz, L. W.; Schwarzkopf, D.; Ramaswamy, V.; Oppenheimer, M.

2005-05-01

Carbon dioxide emissions from fossil-fuel consumption are presented for the five Asian countries that are among the global leaders in anthropogenic carbon emissions: China (13% of global total), Japan (5% of global total), India (5% of global total), South Korea (2% of global total), and Indonesia (1% of global total). Together, these five countries represent over a quarter of the world's fossil-fuel based carbon emissions. Moreover, these countries are rapidly developing and energy demand has grown dramatically in the last two decades. A method is developed to estimate the spatial and seasonal flux of fossil-fuel consumption, thereby greatly improving the temporal and spatial resolution of anthropogenic carbon dioxide emissions. Currently, only national annual data for anthropogenic carbon emissions are available, and as such, no understanding of seasonal or sub-national patterns of emissions are possible. This methodology employs fuel distribution data from representative sectors of the fossil-fuel market to determine the temporal and spatial patterns of fuel consumption. These patterns of fuel consumption are then converted to patterns of carbon emissions. The annual total emissions estimates produced by this method are consistent to those maintained by the United Nations. Improved estimates of temporal and spatial resolution of the human based carbon emissions allows for better projections about future energy demands, carbon emissions, and ultimately the global carbon cycle.

Hydrogen Storage Characteristics of Nanocrystalline and Amorphous Nd-Mg-Ni-Based NdMg12-Type Alloys Synthesized via Mechanical Milling

NASA Astrophysics Data System (ADS)

Zhang, Yanghuan; Shang, Hongwei; Hou, Zhonghui; Yuan, Zeming; Yang, Tai; Qi, Yan

2016-12-01

In this study, Mg was partially substituted by Ni with the intent of improving the hydrogen storage kinetics performance of NdMg12-type alloy. Mechanical milling technology was adopted to fabricate the nanocrystalline and amorphous NdMg11Ni + x wt pct Ni ( x = 100, 200) alloys. The effects of Ni content and milling duration on the microstructures and hydrogen storage kinetics of as-milled alloys have been systematically investigated. The structures were characterized by XRD and HRTEM. The electrochemical hydrogen storage properties were tested by an automatic galvanostatic system. Moreover, the gaseous hydrogen storage properties were investigated by Sievert apparatus and a differential scanning calorimeter connected with a H2 detector. Hydrogen desorption activation energy of alloy hydrides was estimated by using Arrhenius and Kissinger methods. The results reveal that the increase of Ni content dramatically ameliorates the gaseous and electrochemical hydrogen storage kinetics performance of the as-milled alloys. Furthermore, high rate discharge ability (HRD) reach the maximum value with the variation of milling time. The maximum HRDs of the NdMg11Ni + x wt pct Ni ( x = 100, 200) alloys are 80.24 and 85.17 pct. The improved gaseous hydrogen storage kinetics of alloys via increasing Ni content and milling time can be attributed to a decrease in the hydrogen desorption activation energy.

Polysulfide-Blocking Microporous Polymer Membrane Tailored for Hybrid Li-Sulfur Flow Batteries.

PubMed

Li, Changyi; Ward, Ashleigh L; Doris, Sean E; Pascal, Tod A; Prendergast, David; Helms, Brett A

2015-09-09

Redox flow batteries (RFBs) present unique opportunities for multi-hour electrochemical energy storage (EES) at low cost. Too often, the barrier for implementing them in large-scale EES is the unfettered migration of redox active species across the membrane, which shortens battery life and reduces Coulombic efficiency. To advance RFBs for reliable EES, a new paradigm for controlling membrane transport selectivity is needed. We show here that size- and ion-selective transport can be achieved using membranes fabricated from polymers of intrinsic microporosity (PIMs). As a proof-of-concept demonstration, a first-generation PIM membrane dramatically reduced polysulfide crossover (and shuttling at the anode) in lithium-sulfur batteries, even when sulfur cathodes were prepared as flowable energy-dense fluids. The design of our membrane platform was informed by molecular dynamics simulations of the solvated structures of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) vs lithiated polysulfides (Li2Sx, where x = 8, 6, and 4) in glyme-based electrolytes of different oligomer length. These simulations suggested polymer films with pore dimensions less than 1.2-1.7 nm might incur the desired ion-selectivity. Indeed, the polysulfide blocking ability of the PIM-1 membrane (∼0.8 nm pores) was improved 500-fold over mesoporous Celgard separators (∼17 nm pores). As a result, significantly improved battery performance was demonstrated, even in the absence of LiNO3 anode-protecting additives.

Hypothalamic Vitamin D Improves Glucose Homeostasis and Reduces Weight.

PubMed

Sisley, Stephanie R; Arble, Deanna M; Chambers, Adam P; Gutierrez-Aguilar, Ruth; He, Yanlin; Xu, Yong; Gardner, David; Moore, David D; Seeley, Randy J; Sandoval, Darleen A

2016-09-01

Despite clear associations between vitamin D deficiency and obesity and/or type 2 diabetes, a causal relationship is not established. Vitamin D receptors (VDRs) are found within multiple tissues, including the brain. Given the importance of the brain in controlling both glucose levels and body weight, we hypothesized that activation of central VDR links vitamin D to the regulation of glucose and energy homeostasis. Indeed, we found that small doses of active vitamin D, 1α,25-dihydroxyvitamin D3 (1,25D3) (calcitriol), into the third ventricle of the brain improved glucose tolerance and markedly increased hepatic insulin sensitivity, an effect that is dependent upon VDR within the paraventricular nucleus of the hypothalamus. In addition, chronic central administration of 1,25D3 dramatically decreased body weight by lowering food intake in obese rodents. Our data indicate that 1,25D3-mediated changes in food intake occur through action within the arcuate nucleus. We found that VDR colocalized with and activated key appetite-regulating neurons in the arcuate, namely proopiomelanocortin neurons. Together, these findings define a novel pathway for vitamin D regulation of metabolism with unique and divergent roles for central nervous system VDR signaling. Specifically, our data suggest that vitamin D regulates glucose homeostasis via the paraventricular nuclei and energy homeostasis via the arcuate nuclei. © 2016 by the American Diabetes Association.

High Temperature Chemistry of Rare Earth Compounds: Dramatic Examples of Periodicity.

ERIC Educational Resources Information Center

Cater, E. David

1978-01-01

Reports that energy required to promote a 4f electron to the 5d level has a profound and predictable influence on the systematics of reactions involving conversion of rare earth atoms from combined to free states. (Author/MA)

An Evaluation of Ecotoxicity Test Guidelines: Their Adequacy for Nanomaterials

EPA Science Inventory

Advances in nanotechnology are resulting in the production of new nanomaterials at a rapid pace. Driving the dramatic development of new materials and products is the prospect of stronger and lighter materials, better and more efficient energy systems, potential tremendous benefi...

A versatile strategy toward binary three-dimensional architectures based on engineering graphene aerogels with porous carbon fabrics for supercapacitors.

PubMed

Song, Wei-Li; Song, Kuo; Fan, Li-Zhen

2015-02-25

Graphene-based supercapacitors and related flexible devices have attracted great attention because of the increasing demands in the energy storage. As promising three-dimensional (3D) nanostructures in the supercapacitor electrodes, graphene-based aerogels have been paid dramatic attention recently, and numerous methods have been developed for enhancing their performance in energy storage. In this study, an exclusive strategy is presented toward directly in situ growing reduced graphene oxide (RGO) aerogels inside the 3D porous carbon fabrics for engineering the interfaces of the resulting binary 3D architectures. Such unique architectures have shown various advantages in the improvements of the nanostructures and chemical compositions, allowing them to possess much enhanced electrochemical properties (391, 229, and 195 F g(-1) at current densities of 0.1, 1, and 5 A g(-1), respectively) with excellent cycling stability in comparison with the neat RGO aerogels. The results of the performance in the flexible all-solid-state supercapacitors along with discussion on the related mechanisms in the electrochemical properties indicate the remaining issues and associated opportunities in the development of advanced energy storage devices. This strategy is relatively facile, versatile, and tunable, which highlights a unique platform for engineering various 3D porous structures in many fields.

Extracting Aggregation Free Energies of Mixed Clusters from Simulations of Small Systems: Application to Ionic Surfactant Micelles.

PubMed

Zhang, X; Patel, L A; Beckwith, O; Schneider, R; Weeden, C J; Kindt, J T

2017-11-14

Micelle cluster distributions from molecular dynamics simulations of a solvent-free coarse-grained model of sodium octyl sulfate (SOS) were analyzed using an improved method to extract equilibrium association constants from small-system simulations containing one or two micelle clusters at equilibrium with free surfactants and counterions. The statistical-thermodynamic and mathematical foundations of this partition-enabled analysis of cluster histograms (PEACH) approach are presented. A dramatic reduction in computational time for analysis was achieved through a strategy similar to the selector variable method to circumvent the need for exhaustive enumeration of the possible partitions of surfactants and counterions into clusters. Using statistics from a set of small-system (up to 60 SOS molecules) simulations as input, equilibrium association constants for micelle clusters were obtained as a function of both number of surfactants and number of associated counterions through a global fitting procedure. The resulting free energies were able to accurately predict micelle size and charge distributions in a large (560 molecule) system. The evolution of micelle size and charge with SOS concentration as predicted by the PEACH-derived free energies and by a phenomenological four-parameter model fit, along with the sensitivity of these predictions to variations in cluster definitions, are analyzed and discussed.

Freestanding hierarchically porous carbon framework decorated by polyaniline as binder-free electrodes for high performance supercapacitors

NASA Astrophysics Data System (ADS)

Miao, Fujun; Shao, Changlu; Li, Xinghua; Wang, Kexin; Lu, Na; Liu, Yichun

2016-10-01

Freestanding hierarchically porous carbon electrode materials with favorable features of large surface areas, hierarchical porosity and continuous conducting pathways are very attractive for practical applications in electrochemical devices. Herein, three-dimensional freestanding hierarchically porous carbon (HPC) materials have been fabricated successfully mainly by the facile phase separation method. In order to further improve the energy storage ability, polyaniline (PANI) with high pseudocapacitance has been decorated on HPC through in situ chemical polymerization of aniline monomers. Benefiting from the synergistic effects between HPC and PANI, the resulting HPC/PANI composites as electrode materials present dramatic electrochemical performance with high specific capacitance up to 290 F g-1 at 0.5 A g-1 and good rate capability with ∼86% (248 F g-1) capacitance retention at 64 A g-1 of initial capacitance in three-electrode configuration. Moreover, the as-assembled symmetric supercapacitor based on HPC/PANI composites also demonstrates good capacitive properties with high energy density of 9.6 Wh kg-1 at 223 W kg-1 and long-term cycling stability with 78% capacitance retention after 10 000 cycles. Therefore, this work provides a new approach for designing high-performance electrodes with exceptional electrochemical performance, which are very promising for practical application in the energy storage field.

Long-range corrected density functional theory with accelerated Hartree-Fock exchange integration using a two-Gaussian operator [LC-ωPBE(2Gau)].

PubMed

Song, Jong-Won; Hirao, Kimihiko

2015-10-14

Since the advent of hybrid functional in 1993, it has become a main quantum chemical tool for the calculation of energies and properties of molecular systems. Following the introduction of long-range corrected hybrid scheme for density functional theory a decade later, the applicability of the hybrid functional has been further amplified due to the resulting increased performance on orbital energy, excitation energy, non-linear optical property, barrier height, and so on. Nevertheless, the high cost associated with the evaluation of Hartree-Fock (HF) exchange integrals remains a bottleneck for the broader and more active applications of hybrid functionals to large molecular and periodic systems. Here, we propose a very simple yet efficient method for the computation of long-range corrected hybrid scheme. It uses a modified two-Gaussian attenuating operator instead of the error function for the long-range HF exchange integral. As a result, the two-Gaussian HF operator, which mimics the shape of the error function operator, reduces computational time dramatically (e.g., about 14 times acceleration in C diamond calculation using periodic boundary condition) and enables lower scaling with system size, while maintaining the improved features of the long-range corrected density functional theory.

Global sustainability and key needs in future automotive design.

PubMed

McAuley, John W

2003-12-01

The number of light vehicle registrations is forecast to increase worldwide by a factor of 3-5 over the next 50 years. This will dramatically increase environmental impacts worldwide of automobiles and light trucks. If light vehicles are to be environmentally sustainable globally, the automotive industry must implement fundamental changes in future automotive design. Important factors in assessing automobile design needs include fuel economy and reduced emissions. Many design parameters can impact vehicle air emissions and energy consumption including alternative fuel or engine technologies, rolling resistance, aerodynamics, drive train design, friction, and vehicle weight. Of these, vehicle weight is key and will translate into reduced energy demand across all energy distribution elements. A new class of vehicles is needed that combines ultra-light design with a likely hybrid or fuel cell engine technology. This could increase efficiency by a factor of 3-5 and reduce air emissions as well. Advanced lightweight materials, such as plastics or composites, will need to overtake the present metal-based infrastructure. Incorporating design features to facilitate end-of-life recycling and recovery is also important. The trend will be towards fewer materials and parts in vehicle design, combined with ease of disassembly. Mono-material construction can create vehicle design with improved recyclability as well as reduced numbers of parts and weight.

A muscle-specific knockout implicates nuclear receptor coactivator MED1 in the regulation of glucose and energy metabolism.

PubMed

Chen, Wei; Zhang, Xiaoting; Birsoy, Kivanc; Roeder, Robert G

2010-06-01

As conventional transcriptional factors that are activated in diverse signaling pathways, nuclear receptors play important roles in many physiological processes that include energy homeostasis. The MED1 subunit of the Mediator coactivator complex plays a broad role in nuclear receptor-mediated transcription by anchoring the Mediator complex to diverse promoter-bound nuclear receptors. Given the significant role of skeletal muscle, in part through the action of nuclear receptors, in glucose and fatty acid metabolism, we generated skeletal muscle-specific Med1 knockout mice. Importantly, these mice show enhanced insulin sensitivity and improved glucose tolerance as well as resistance to high-fat diet-induced obesity. Furthermore, the white muscle of these mice exhibits increased mitochondrial density and expression of genes specific to type I and type IIA fibers, indicating a fast-to-slow fiber switch, as well as markedly increased expression of the brown adipose tissue-specific UCP-1 and Cidea genes that are involved in respiratory uncoupling. These dramatic results implicate MED1 as a powerful suppressor in skeletal muscle of genetic programs implicated in energy expenditure and raise the significant possibility of therapeutical approaches for metabolic syndromes and muscle diseases through modulation of MED1-nuclear receptor interactions.

Enhanced mechanical energy harvesting ability of electrospun poly(vinylidene fluoride)/hectorite clay nanocomposites

NASA Astrophysics Data System (ADS)

Rahman, Wahida; Ghosh, Sujoy Kumar; Middya, Tapas Ranjan; Mandal, Dipankar

2018-04-01

We report on enhanced piezoelectric properties of poly (vinylidene fluoride) (PVDF)/hectorite nano-clay composites prepared by electrospinning process. The investigation on the effects of the nano-filler in the crystalline phase and piezoelectric properties reveals dramatic enhancement of piezoelectric β-phase (95%) due to synergistic effect of electrospinning and nano-clay loading. As a result, the prepared nanocomposite possesses higher mechanical energy harvesting ability than that of pure PVDF.

Co-Optimization of Fuels and Engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farrell, John

2016-03-24

The Co-Optimization of Fuels and Engines (Co-Optima) initiative is a new DOE initiative focused on accelerating the introduction of affordable, scalable, and sustainable biofuels and high-efficiency, low-emission vehicle engines. The simultaneous fuels and vehicles research and development (R&D) are designed to deliver maximum energy savings, emissions reduction, and on-road vehicle performance. The initiative's integrated approach combines the previously independent areas of biofuels and combustion R&D, bringing together two DOE Office of Energy Efficiency & Renewable Energy research offices, ten national laboratories, and numerous industry and academic partners to simultaneously tackle fuel and engine research and development (R&D) to maximize energymore » savings and on-road vehicle performance while dramatically reducing transportation-related petroleum consumption and greenhouse gas (GHG) emissions. This multi-year project will provide industry with the scientific underpinnings required to move new biofuels and advanced engine systems to market faster while identifying and addressing barriers to their commercialization. This project's ambitious, first-of-its-kind approach simultaneously tackles fuel and engine innovation to co-optimize performance of both elements and provide dramatic and rapid cuts in fuel use and emissions. This presentation provides an overview of the project.« less

Dramatic improvement of the solubility of pseudolaric acid B by cyclodextrin complexation: preparation, characterization and validation.

PubMed

Chi, Liandi; Liu, Ruihao; Guo, Tao; Wang, Manli; Liao, Zuhua; Wu, Li; Li, Haiyan; Wu, Deling; Zhang, Jiwen

2015-02-20

As one of the most important technologies to improve the solubility of poorly water-soluble drugs, the solubilization effects of cyclodextrins (CDs) complexation are, on occasions, not as large as expected, which tends to detract from the wider application of CDs. In this study, a dramatic improvement of the solubility of pseudolaric acid B (PAB) by CDs has been found with a 600 fold increase by HP-β-CD complexation. In addition, the solubility enhancement of PAB by various CDs, including α-CD, β-CD, γ-CD, HP-β-CD and SBE-β-CD was investigated by phase solubility studies. The inclusion complex of PAB/HP-β-CD was prepared by different methods and characterized by differential scanning calorimetry (DSC), powder X-ray diffractometry (XRD), nuclear magnetic resonance spectroscopy ((1)H NMR) together with molecular simulation. The results indicated that the solubility of PAB was increased to 15.78mgmL(-1) in the presence of 30% HP-β-CD, which is a 600 fold increase compared with that in pure water. And the chemical stability of PAB in PBS (pH 7.4) can be enhanced. The results of DSC and XRD showed the absence of crystallinity in the PAB/HP-β-CD inclusion complex prepared by the saturated water solution method. The results of (1)H NMR together with molecular simulation indicated the conjugated diene side-chain of PAB was included into the cavity of HP-β-CD, with the free energy of -20.34±4.69kJmol(-1). While the enzymatic degradation site of the carboxyl polar bond is located in the hydrophilic outer of HP-β-CD resulted in no significant difference for the enzymatic degradation rate between PAB and PAB/HP-β-CD complexes in rat plasma. In summary, the PAB/HP-β-CD inclusion complex prepared in this study can greatly improve the solubility and chemical stability of PAB, which will result in the in vivo administration of PAB as a liquid solution. Copyright © 2015 Elsevier B.V. All rights reserved.

Implementing Innovative Elementary Literacy Programs. Program Report.

ERIC Educational Resources Information Center

Schwab, R. G. Jerry; And Others

This four-document collection describes the implementation processes of dramatically improved literacy programs in elementary schools which are leading the move to restructure literacy education in the Northwest (Alaska, Idaho, Montana, Oregon, and Washington). The first document in the collection, "Strategies for Improving School-Wide…

Dramatic Improvements in Beach Water Quality Following Gull Removal

EPA Science Inventory

Gulls are often cited as important contributors of fecal contamination to surface waters, and some recreational beaches have used gull control measures to improve microbial water quality. In this study, gulls were chased from a Lake Michigan beach using specially trained dogs, a...

Dynamic shear-lag model for understanding the role of matrix in energy dissipation in fiber-reinforced composites.

PubMed

Liu, Junjie; Zhu, Wenqing; Yu, Zhongliang; Wei, Xiaoding

2018-07-01

Lightweight and high impact performance composite design is a big challenge for scientists and engineers. Inspired from well-known biological materials, e.g., the bones, spider silk, and claws of mantis shrimp, artificial composites have been synthesized for engineering applications. Presently, the design of ballistic resistant composites mainly emphasizes the utilization of light and high-strength fibers, whereas the contribution from matrix materials receives less attention. However, recent ballistic experiments on fiber-reinforced composites challenge our common sense. The use of matrix with "low-grade" properties enhances effectively the impact performance. In this study, we establish a dynamic shear-lag model to explore the energy dissipation through viscous matrix materials in fiber-reinforced composites and the associations of energy dissipation characteristics with the properties and geometries of constituents. The model suggests that an enhancement in energy dissipation before the material integrity is lost can be achieved by tuning the shear modulus and viscosity of a matrix. Furthermore, our model implies that an appropriately designed staggered microstructure, adopted by many natural composites, can repeatedly activate the energy dissipation process and thus improve dramatically the impact performance. This model demonstrates the role of matrix in energy dissipation, and stimulates new advanced material design concepts for ballistic applications. Biological composites found in nature often possess exceptional mechanical properties that man-made materials haven't be able to achieve. For example, it is predicted that a pencil thick spider silk thread can stop a flying Boeing airplane. Here, by proposing a dynamic shear-lag model, we investigate the relationships between the impact performance of a composite with the dimensions and properties of its constituents. Our analysis suggests that the impact performance of fiber-reinforced composites could improve surprisingly with "low-grade" matrix materials, and discontinuities (often regarded as "defects") may play an important role in energy dissipation. Counter-intuitive as it may seem, our work helps understanding the secrets of the outstanding dynamic properties of some biological materials, and inspire novel ideas for man-made composites. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

Recent years have brought dramatic advances in the scientific understanding of fusion plasmas and in the generation of fusion power in the laboratory. Today, there is little doubt that fusion energy production is feasible. The challenge is to make fusion energy practical. As a result of the advances of the last few years, there are now exciting opportunities to optimize fusion systems so that an attractive new energy source will be available when it may be needed in the middle of the next century. The risk of conflicts arising from energy shortages and supply cutoffs, as well as the riskmore » of severe environmental impacts from existing methods of energy production, are among the reasons to pursue these opportunities.« less

Energy Policy Case Study - Texas: Wind, Markets, and Grid Modernization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orrell, Alice C.; Homer, Juliet S.; Bender, Sadie R.

This document presents a case study of energy policies in Texas related to power system transformation, renewable energy and distributed energy resources (DERs). Texas has experienced a dramatic increase in installed wind capacity, from 116 MW in 2000 to over 15,000 MW in 2015. This achievement was enabled by the designation of Competitive Renewable Energy Zones (CREZs) and new transmission lines that transmit wind to load centers. This report highlights nascent efforts to include DERs in the ERCOT market. As costs decline and adoption rates increase, ERCOT expects distributed generation to have an increasing effect on grid operations, while bringingmore » potentially valuable new resources to the wholesale markets.« less

Integration of energy analytics and smart energy microgrid into mobile medicine operations for the 2012 Democratic National Convention.

PubMed

McCahill, Peter W; Noste, Erin E; Rossman, A J; Callaway, David W

2014-12-01

Disasters create major strain on energy infrastructure in affected communities. Advances in microgrid technology offer the potential to improve "off-grid" mobile disaster medical response capabilities beyond traditional diesel generation. The Carolinas Medical Center's mobile emergency medical unit (MED-1) Green Project (M1G) is a multi-phase project designed to demonstrate the benefits of integrating distributive generation (DG), high-efficiency batteries, and "smart" energy utilization in support of major out-of-hospital medical response operations. Carolinas MED-1 is a mobile medical facility composed of a fleet of vehicles and trailers that provides comprehensive medical care capacities to support disaster response and special-event operations. The M1G project partnered with local energy companies to deploy energy analytics and an energy microgrid in support of mobile clinical operations for the 2012 Democratic National Convention (DNC) in Charlotte, North Carolina (USA). Energy use data recorded throughout the DNC were analyzed to create energy utilization models that integrate advanced battery technology, solar photovoltaic (PV), and energy conservation measures (ECM) to improve future disaster response operations. The generators that supply power for MED-1 have a minimum loading ratio (MLR) of 30 kVA. This means that loads below 30 kW lead to diesel fuel consumption at the same rate as a 30 kW load. Data gathered from the two DNC training and support deployments showed the maximum load of MED-1 to be around 20 kW. This discrepancy in MLR versus actual load leads to significant energy waste. The lack of an energy storage system reduces generator efficiency and limits integration of alternative energy generation strategies. A storage system would also allow for alternative generation sources, such as PV, to be incorporated. Modeling with a 450 kWh battery bank and 13.5 kW PV array showed a 2-fold increase in potential deployment times using the same amount of fuel versus the current conventional system. The M1G Project demonstrated that the incorporation of a microgrid energy management system and a modern battery system maximize the MED-1 generators' output. Using a 450 kWh battery bank and 13.5 kW PV array, deployment operations time could be more than doubled before refueling. This marks a dramatic increase in patient care capabilities and has significant public health implications. The results highlight the value of smart-microgrid technology in developing energy independent mobile medical capabilities and expanding cost-effective, high-quality medical response.

Disentangling road network impacts: The need for a holistic approach

USDA-ARS?s Scientific Manuscript database

Traditional and alternative energy development, logging and mining activities, together with off-highway vehicles (OHV) and exurban development, have increased the density of linear disturbances on public and private lands throughout the world. We argue that the dramatic increase in linear disturba...

Brown adipose tissue transplantation ameliorates polycystic ovary syndrome

PubMed Central

Yuan, Xiaoxue; Hu, Tao; Zhao, Han; Huang, Yuanyuan; Ye, Rongcai; Lin, Jun; Zhang, Chuanhai; Zhang, Hanlin; Wei, Gang; Zhou, Huiqiao; Dong, Meng; Zhao, Jun; Wang, Haibin; Liu, Qingsong; Lee, Hyuek Jong; Jin, Wanzhu; Chen, Zi-Jiang

2016-01-01

Polycystic ovary syndrome (PCOS), which is characterized by anovulation, hyperandrogenism, and polycystic ovaries, is a complex endocrinopathy. Because the cause of PCOS at the molecular level is largely unknown, there is no cure or specific treatment for PCOS. Here, we show that transplantation of brown adipose tissue (BAT) reversed anovulation, hyperandrogenism, and polycystic ovaries in a dehydroepiandrosterone (DHEA)-induced PCOS rat. BAT transplantation into a PCOS rat significantly stabilized menstrual irregularity and improved systemic insulin sensitivity up to a normal level, which was not shown in a sham-operated or muscle-transplanted PCOS rat. Moreover, BAT transplantation, not sham operation or muscle transplantation, surprisingly improved fertility in PCOS rats. Interestingly, BAT transplantation activated endogenous BAT and thereby increased the circulating level of adiponectin, which plays a prominent role in whole-body energy metabolism and ovarian physiology. Consistent with BAT transplantation, administration of adiponectin protein dramatically rescued DHEA-induced PCOS phenotypes. These results highlight that endogenous BAT activity is closely related to the development of PCOS phenotypes and that BAT activation might be a promising therapeutic option for the treatment of PCOS. PMID:26903641

On the Improvement of Convergence Performance for Integrated Design of Wind Turbine Blade Using a Vector Dominating Multi-objective Evolution Algorithm

NASA Astrophysics Data System (ADS)

Wang, L.; Wang, T. G.; Wu, J. H.; Cheng, G. P.

2016-09-01

A novel multi-objective optimization algorithm incorporating evolution strategies and vector mechanisms, referred as VD-MOEA, is proposed and applied in aerodynamic- structural integrated design of wind turbine blade. In the algorithm, a set of uniformly distributed vectors is constructed to guide population in moving forward to the Pareto front rapidly and maintain population diversity with high efficiency. For example, two- and three- objective designs of 1.5MW wind turbine blade are subsequently carried out for the optimization objectives of maximum annual energy production, minimum blade mass, and minimum extreme root thrust. The results show that the Pareto optimal solutions can be obtained in one single simulation run and uniformly distributed in the objective space, maximally maintaining the population diversity. In comparison to conventional evolution algorithms, VD-MOEA displays dramatic improvement of algorithm performance in both convergence and diversity preservation for handling complex problems of multi-variables, multi-objectives and multi-constraints. This provides a reliable high-performance optimization approach for the aerodynamic-structural integrated design of wind turbine blade.

Nanotechnology applications to desalination : a report for the joint water reuse & desalination task force.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brady, Patrick Vane; Mayer, Tom; Cygan, Randall Timothy

2011-01-01

Nanomaterials and nanotechnology methods have been an integral part of international research over the past decade. Because many traditional water treatment technologies (e.g. membrane filtration, biofouling, scale inhibition, etc.) depend on nanoscale processes, it is reasonable to expect one outcome of nanotechnology research to be better, nano-engineered water treatment approaches. The most immediate, and possibly greatest, impact of nanotechnology on desalination methods will likely be the development of membranes engineered at the near-molecular level. Aquaporin proteins that channel water across cell membranes with very low energy inputs point to the potential for dramatically improved performance. Aquaporin-laced polymer membranes and aquaporin-mimickingmore » carbon nanotubes and metal oxide membranes developed in the lab support this. A critical limitation to widespread use of nanoengineered desalination membranes will be their scalability to industrial fabrication processes. Subsequent, long-term improvements in nanoengineered membranes may result in self-healing membranes that ideally are (1) more resistant to biofouling, (2) have biocidal properties, and/or (3) selectively target trace contaminants.« less

Comparisons between MCNP, EGS4 and experiment for clinical electron beams.

PubMed

Jeraj, R; Keall, P J; Ostwald, P M

1999-03-01

Understanding the limitations of Monte Carlo codes is essential in order to avoid systematic errors in simulations, and to suggest further improvement of the codes. MCNP and EGS4, Monte Carlo codes commonly used in medical physics, were compared and evaluated against electron depth dose data and experimental backscatter results obtained using clinical radiotherapy beams. Different physical models and algorithms used in the codes give significantly different depth dose curves and electron backscattering factors. The default version of MCNP calculates electron depth dose curves which are too penetrating. The MCNP results agree better with experiment if the ITS-style energy-indexing algorithm is used. EGS4 underpredicts electron backscattering for high-Z materials. The results slightly improve if optimal PRESTA-I parameters are used. MCNP simulates backscattering well even for high-Z materials. To conclude the comparison, a timing study was performed. EGS4 is generally faster than MCNP and use of a large number of scoring voxels dramatically slows down the MCNP calculation. However, use of a large number of geometry voxels in MCNP only slightly affects the speed of the calculation.

Homebuilt single-molecule scanning confocal fluorescence microscope studies of single DNA/protein interactions.

PubMed

Zheng, Haocheng; Goldner, Lori S; Leuba, Sanford H

2007-03-01

Many technical improvements in fluorescence microscopy over the years have focused on decreasing background and increasing the signal to noise ratio (SNR). The scanning confocal fluorescence microscope (SCFM) represented a major improvement in these efforts. The SCFM acquires signal from a thin layer of a thick sample, rejecting light whose origin is not in the focal plane thereby dramatically decreasing the background signal. A second major innovation was the advent of high quantum-yield, low noise, single-photon counting detectors. The superior background rejection of SCFM combined with low-noise, high-yield detectors makes it possible to detect the fluorescence from single-dye molecules. By labeling a DNA molecule or a DNA/protein complex with a donor/acceptor dye pair, fluorescence resonance energy transfer (FRET) can be used to track conformational changes in the molecule/complex itself, on a single molecule/complex basis. In this methods paper, we describe the core concepts of SCFM in the context of a study that uses FRET to reveal conformational fluctuations in individual Holliday junction DNA molecules and nucleosomal particles. We also discuss data processing methods for SCFM.

Household energy use in Asian cities: Responding to development success

NASA Astrophysics Data System (ADS)

Tyler, Stephen R.

In the past 10-15 years, gains in household income and urban development in many countries in Asia have led to significant shifts in household use of fuels away from traditional, biomass-based household fuels to modern, fossil fuels. These results suggest that, while the global atmospheric emissions implications need further analysis, the local air quality effects of urban household fuel use changes have been positive. These changes also demonstrate improvements in living conditions, particularly for poor women and children most affected by indoor air quality. However, for electricity use, where there is evidence of dramatic increases in household consumption, the longer term implications for atmospheric emissions are more troubling. Rapid demand growth in the urban household sector is contributing to huge increases in thermal electric generating capacity needs in Asia. Improving technologies of electricity use in the household sector appears to be easily achievable and could be stimulated through market and policy mechanisms which have been used elsewhere. These measures offer the prospect of real environmental and economic gains without sacrificing lifestyle advantages of electrical appliance use in households.

Throwing computing into reverse

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frank, Michael P.

For more than 50 years, computers have made steady and dramatic improvements, all thanks to Moore’s Law—the exponential increase over time in the number of transistors that can be fabricated on an integrated circuit of a given size. Moore’s Law owed its success to the fact that as transistors were made smaller, they became simultaneously cheaper, faster, and more energy efficient. The payoff from this win-win-win scenario enabled reinvestment in semiconductor fabrication technology that could make even smaller, more densely-packed transistors. And so this virtuous cycle continued, decade after decade. Now though, experts in industry, academia, and government laboratories anticipatemore » that semiconductor miniaturization won’t continue much longer—maybe 10 years or so, at best. Making transistors smaller no longer yields the improvements it used to. The physical characteristics of small transistors forced clock speeds to cease getting faster more than a decade ago, which drove the industry to start building chips with multiple cores. But even multi-core architectures must contend with increasing amounts of “dark silicon,” areas of the chip that must be powered off to avoid overheating.« less

Primary focal hyperhidrosis: diagnosis and management. .

PubMed

Wang, Rena; Solish, Nowell; Murray, Christian A

2008-12-01

Primary focal hyperhidrosis is a common and serious medical condition that causes considerable psychosocial morbidity. Diagnostic and effective management strategies can improve patients' quality of living dramatically.

Non-Traditional Methods of Improving the Communication Skills of Disadvantaged Students

ERIC Educational Resources Information Center

Wilson, Brenda M.; Power, Marian E.

1978-01-01

Educators are encouraged to use some of the non-traditional student-centered methods for improving the communication skills of disadvantaged students, including technological aids such as books, tapes, cable T.V., video tapes, computers, etc., and devices such as role playing and dramatizations. (AM)

Rotational Energy in a Physical Pendulum

ERIC Educational Resources Information Center

Monteiro, Martín; Cabeza, Cecilia; Marti, Arturo C.

2014-01-01

Smartphone usage has expanded dramatically in recent years worldwide. This revolution also has impact in undergraduate laboratories where different experiences are facilitated by the use of the sensors usually included in these devices. Recently, in several articles published in the literature, the use of "smartphones" has been proposed…

Illuminating the Way.

ERIC Educational Resources Information Center

Murphy, Peter

1997-01-01

Details the dramatic changes in school lighting. Describes how lighting will be more closely integrated into the "smart" school building of tomorrow and how lighting systems will evolve with schools as technology changes. Claims that direct/indirect lighting systems will serve computer users as well as reduce energy and maintenance costs. (RJM)

Engineered Nanomaterial Ecological Effects Research within ORD's National Health and Environmental Effects Laboratory

EPA Science Inventory

Advances in nanotechnology are resulting in the production of new nanomaterials at a rapid pace. Driving the dramatic development of new materials and products is the prospect of stronger and lighter materials, better and more efficient energy systems, potential tremendous benefi...

Plutonium Recycle: The Fateful Step

ERIC Educational Resources Information Center

Speth, J. Gustave; And Others

1974-01-01

Calls attention to the fact that if the Atomic Energy Commission proceeds with its plans to authorize the nuclear power industry to use plutonium as a fuel in commercial nuclear reactors around the country, this will result in a dramatic escalation in the risks posed by nuclear power. (PEB)

Dietary recommendations and athletic menstrual dysfunction.

PubMed

Manore, Melinda M

2002-01-01

Exercise-induced or athletic menstrual dysfunction (amenorrhoea, oligomenorrhoea, anovulation, luteal phase deficiency, delayed menarche) is more common in active women and can significantly affect health and sport performance. Although athletic amenorrhoea represents the most extreme form of menstrual dysfunction, other forms can also result in suppressed estrogen levels and affect bone health and fertility. A number of factors, such as energy balance, exercise intensity and training practices, bodyweight and composition, disordered eating behaviours, and physical and emotional stress levels, may contribute to the development of athletic menstrual dysfunction. There also appears to be a high degree of individual variation with respect to the susceptibility of the reproductive axis to exercise and diet-related stresses. The dietary issues of the female athlete with athletic menstrual dysfunction are similar to those of her eumenorrhoeic counterpart. The most common nutrition issues in active women are poor energy intake and/or poor food selection, which can lead to poor intakes of protein, carbohydrate and essential fatty acids. The most common micronutrients to be low are the bone-building nutrients, especially calcium, the B vitamins, iron and zinc. If energy drain is the primary contributing factor to athletic menstrual dysfunction, improved energy balance will improve overall nutritional status and may reverse the menstrual dysfunction, thus returning the athlete to normal reproductive function. Because bone health can be compromised in female athletes with menstrual dysfunction, intakes of bone-building nutrients are especially important. Iron and zinc are typically low in the diets of female athletes if meat products are avoided. Adequate intake of the B vitamins is also important to ensure adequate energy production and the building and repair of muscle tissue. This review briefly discusses the various factors that may affect athletic menstrual dysfunction and two of the proposed mechanisms: the energy-drain and exercise-intensity hypotheses. Because energy drain can be a primary contributor to athletic menstrual dysfunction, recommendations for energy and the macro- and micronutrients are reviewed. Methods for helping the female athlete to reverse athletic menstrual dysfunction are discussed. The health consequences of trying to restrict energy intake too dramatically while training are also reviewed, as is the importance of screening athletes for disordered eating. Vitamins and minerals of greatest concern for the female athlete are addressed and recommendations for intake are given.

Exceptional Children Conference Papers: Gifted and Talented.

ERIC Educational Resources Information Center

Council for Exceptional Children, Arlington, VA.

Educators concerned with improving educational opportunities for the gifted need to consider ways to achieve their ends within the realities of the political system. Federal programs cannot be expected to provide ideas which will dramatically improve education for the gifted nor to provide large quantities of money. The federal government can…

Using JournalMap to improve discovery and visualization of rangeland scientific knowledge

USDA-ARS?s Scientific Manuscript database

Most of the ecological research conducted around the world is tied to specific places; however, that location information is locked up in the text and figures of scientific articles in myriad forms that are not easily searchable. While access to ecological literature has improved dramatically in the...

School Turnaround Fever: The Paradoxes of a Historical Practice Promoted as a New Reform

ERIC Educational Resources Information Center

Peck, Craig; Reitzug, Ulrich C.

2014-01-01

School "turnaround" has received significant attention recently in education literature and policy action, especially as a means to dramatically improve urban education. In current common education usage, "turnaround" refers to the rapid, significant improvement in the academic achievement of persistently low-achieving schools.…

Fast large-scale clustering of protein structures using Gauss integrals.

PubMed

Harder, Tim; Borg, Mikael; Boomsma, Wouter; Røgen, Peter; Hamelryck, Thomas

2012-02-15

Clustering protein structures is an important task in structural bioinformatics. De novo structure prediction, for example, often involves a clustering step for finding the best prediction. Other applications include assigning proteins to fold families and analyzing molecular dynamics trajectories. We present Pleiades, a novel approach to clustering protein structures with a rigorous mathematical underpinning. The method approximates clustering based on the root mean square deviation by first mapping structures to Gauss integral vectors--which were introduced by Røgen and co-workers--and subsequently performing K-means clustering. Compared to current methods, Pleiades dramatically improves on the time needed to perform clustering, and can cluster a significantly larger number of structures, while providing state-of-the-art results. The number of low energy structures generated in a typical folding study, which is in the order of 50,000 structures, can be clustered within seconds to minutes.

Comparative Analysis of Miniature Internal Combustion Engine and Electric Motor for UAV Propulsion

NASA Astrophysics Data System (ADS)

Chiclana, Branden Mark

This thesis compares the performance of an engine/fuel tank based propulsion system to a motor/battery based propulsion system of equal total mass. The results show that the endurance of the engine/fuel system at the same thrust output is approximately 5 times greater than that of the motor/battery system. This is a direct result of the fact that the specific energy of the fuel is 20 times that of the lithium-polymer batteries used to power the motor. A method is also developed to account for the additional benefits of fuel consumption (and hence weight reduction) over the course of the flight. Accounting for this effect can increase endurance exponentially. Taken together, the results also demonstrate the dramatic performance improvements that are possible simply by replacing motor/battery systems with engine/fuel systems on small unmanned air vehicles.

Slow Photoelectron Velocity-Map Imaging of Cryogenically Cooled Anions

NASA Astrophysics Data System (ADS)

Weichman, Marissa L.; Neumark, Daniel M.

2018-04-01

Slow photoelectron velocity-map imaging spectroscopy of cryogenically cooled anions (cryo-SEVI) is a powerful technique for elucidating the vibrational and electronic structure of neutral radicals, clusters, and reaction transition states. SEVI is a high-resolution variant of anion photoelectron spectroscopy based on photoelectron imaging that yields spectra with energy resolution as high as 1-2 cm‑1. The preparation of cryogenically cold anions largely eliminates hot bands and dramatically narrows the rotational envelopes of spectral features, enabling the acquisition of well-resolved photoelectron spectra for complex and spectroscopically challenging species. We review the basis and history of the SEVI method, including recent experimental developments that have improved its resolution and versatility. We then survey recent SEVI studies to demonstrate the utility of this technique in the spectroscopy of aromatic radicals, metal and metal oxide clusters, nonadiabatic interactions between excited states of small molecules, and transition states of benchmark bimolecular reactions.

Fatigue crack propagation behaviour of unidirectionally solidified gamma/gamma-prime-delta eutectic alloys. [Ni-Nb-Al alloys

NASA Technical Reports Server (NTRS)

Bretz, P. E.; Hertzberg, R. W.

1979-01-01

Fatigue crack propagation studies were carried out on unidirectionally solidified gamma/gamma-prime-delta (Ni-Nb-Al) alloys over an aluminum content range of 1.5-2.5% by weight. The variation of Al content of as-grown alloys did not significantly affect the crack growth behavior of these eutectic composites. The results indicate that the addition of Al to the eutectic dramatically improved the FCP behavior. The gamma/gamma-prime-delta alloy exhibited crack growth rates for a given stress intensity range that are an order of magnitude lower than those for the gamma-delta alloy. It is suggested that this difference in FCP behavior can be explained on the basis of stacking fault energy considerations. Extensive delaminations at the crack tip were also revealed, which contributed to the superior fatigue response. Delamination was predominantly intergranular in nature.

Propagation of atmospheric-pressure ionization waves along the tapered tube

NASA Astrophysics Data System (ADS)

Xia, Yang; Wang, Wenchun; Liu, Dongping; Yan, Wen; Bi, Zhenhua; Ji, Longfei; Niu, Jinhai; Zhao, Yao

2018-02-01

Gas discharge in a small radius dielectric tube may result in atmospheric pressure plasma jets with high energy and density of electrons. In this study, the atmospheric pressure ionization waves (IWs) were generated inside a tapered tube. The propagation behaviors of IWs inside the tube were studied by using a spatially and temporally resolved optical detection system. Our measurements show that both the intensity and velocity of the IWs decrease dramatically when they propagate to the tapered region. After the taper, the velocity, intensity, and electron density of the IWs are improved with the tube inner diameter decreasing from 4.0 to 0.5 mm. Our analysis indicates that the local gas conductivity and surface charges may play a role in the propagation of the IWs under such a geometrical constraint, and the difference in the dynamics of the IWs after the taper can be related to the restriction in the size of IWs.

Molecular approaches to third generation photovoltaics: photochemical up-conversion

NASA Astrophysics Data System (ADS)

Cheng, Yuen Yap; Fückel, Burkhard; Roberts, Derrick A.; Khoury, Tony; Clady, Rapha"l. G. C. R.; Tayebjee, Murad J. Y.; Piper, Roland; Ekins-Daukes, N. J.; Crossley, Maxwell J.; Schmidt, Timothy W.

2010-08-01

We have investigated a photochemical up-conversion system comprising a molecular mixture of a palladium porphyrin to harvest light, and a polycyclic aromatic hydrocarbon to emit light. The energy of harvested photons is stored as molecular triplet states which then annihilate to bring about up-converted fluorescence. The limiting efficiency of such triplet-triplet annihilation up-conversion has been believed to be 11% for some time. However, by rigorously investigating the kinetics of delayed fluorescence following pulsed excitation, we demonstrate instantaneous annihilation efficiencies exceeding 40%, and limiting efficiencies for the current system of ~60%. We attribute the high efficiencies obtained to the electronic structure of the emitting molecule, which exhibits an exceptionally high T2 molecular state. We utilize the kinetic data obtained to model an up-converting layer irradiated with broadband sunlight, finding that ~3% efficiencies can be obtained with the current system, with this improving dramatically upon optimization of various parameters.

21. century customers: Volume 1 -- Industry and manufacturing. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hanley, P.H.; Asfour, A.; Tripp, S.

1998-12-01

The arrival of 21st century information technologies has compelled traditional heavy industries such as steel, chemicals, and paper/pulp to invest in new plants and technologies, efficiency moves, globalization of sourcing, and aggressive pursuit of foreign direct investment. This report will assist strategic planners and marketing executives charged with identifying the needs of the widely dispersed industrial sector and provide insights regarding how to improve long-term profitability. Understanding and meeting the evolving needs of industrial customers could be critical to the future prosperity of energy enterprises. This report examines five significant industries that are undergoing dramatic changes in their markets andmore » relationships to buyers of their products--steel and aluminum, paper and pulp, chemicals, plastics, and food processing. The report provides a companion to Volume 2, ``21st Century Customers: Volume 2: Business and Commerce``, covering the evolving needs of five commercial sector businesses.« less

Synergistic Impacts of Electrolyte Adsorption on the Thermoelectric Properties of Single-Walled Carbon Nanotubes.

PubMed

Nakano, Motohiro; Nakashima, Takuya; Kawai, Tsuyoshi; Nonoguchi, Yoshiyuki

2017-08-01

Single-walled carbon nanotubes are promising candidates for light-weight and flexible energy materials. Recently, the thermoelectric properties of single-walled carbon nanotubes have been dramatically improved by ionic liquid addition; however, controlling factors remain unsolved. Here the thermoelectric properties of single-walled carbon nanotubes enhanced by electrolytes are investigated. Complementary characterization with absorption, Raman, and X-ray photoelectron spectroscopy reveals that shallow hole doping plays a partial role in the enhanced electrical conductivity. The molecular factors controlling the thermoelectric properties of carbon nanotubes are systematically investigated in terms of the ionic functionalities of ionic liquids. It is revealed that appropriate ionic liquids show a synergistic enhancement in conductivity and the Seebeck coefficient. The discovery of significantly precise doping enables the generation of thermoelectric power factor exceeding 460 µW m - 1 K -2 . © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High performance aluminum–cerium alloys for high-temperature applications

DOE PAGES

Sims, Zachary C.; Rios, Orlando R.; Weiss, David; ...

2017-08-01

Light-weight high-temperature alloys are important to the transportation industry where weight, cost, and operating temperature are major factors in the design of energy efficient vehicles. Aluminum alloys fill this gap economically but lack high-temperature mechanical performance. Alloying aluminum with cerium creates a highly castable alloy, compatible with traditional aluminum alloy additions, that exhibits dramatically improved high-temperature performance. These compositions display a room temperature ultimate tensile strength of 400 MPa and yield strength of 320 MPa, with 80% mechanical property retention at 240 °C. A mechanism is identified that addresses the mechanical property stability of the Al-alloys to at least 300more » °C and their microstructural stability to above 500 °C which may enable applications without the need for heat treatment. Lastly, neutron diffraction under load provides insight into the unusual mechanisms driving the mechanical strength.« less

Near-unity quantum yields from chloride treated CdTe colloidal quantum dots

DOE PAGES

Page, Robert C.; Espinobarro-Velazquez, Daniel; Leontiadou, Marina A.; ...

2014-10-27

Colloidal quantum dots (CQDs) are promising materials for novel light sources and solar energy conversion. However, trap states associated with the CQD surface can produce non-radiative charge recombination that significantly reduces device performance. Here a facile post-synthetic treatment of CdTe CQDs is demonstrated that uses chloride ions to achieve near-complete suppression of surface trapping, resulting in an increase of photoluminescence (PL) quantum yield (QY) from ca. 5% to up to 97.2 ± 2.5%. The effect of the treatment is characterised by absorption and PL spectroscopy, PL decay, scanning transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. We find thismore » process also dramatically improves the air-stability of the CQDs: before treatment the PL is largely quenched after 1 hour of air-exposure, whilst the treated samples showed a PL QY of nearly 50% after more than 12 hours.« less

AGIS -- the Advanced Gamma-ray Imaging System

NASA Astrophysics Data System (ADS)

Krennrich, Frank

2009-05-01

The Advanced Gamma-ray Imaging System, AGIS, is envisioned to become the follow-up mission of the current generation of very high energy gamma-ray telescopes, namely, H.E.S.S., MAGIC and VERITAS. These instruments have provided a glimpse of the TeV gamma-ray sky, showing more than 70 sources while their detailed studies constrain a wealth of physics and astrophysics. The particle acceleration, emission and absorption processes in these sources permit the study of extreme physical conditions found in galactic and extragalactic TeV sources. AGIS will dramatically improve the sensitivity and angular resolution of TeV gamma-ray observations and therefore provide unique prospects for particle physics, astrophysics and cosmology. This talk will provide an overview of the science drivers, scientific capabilities and the novel technical approaches that are pursued to maximize the performance of the large array concept of AGIS.

Bottomonium suppression using a lattice QCD vetted potential

NASA Astrophysics Data System (ADS)

Krouppa, Brandon; Rothkopf, Alexander; Strickland, Michael

2018-01-01

We estimate bottomonium yields in relativistic heavy-ion collisions using a lattice QCD vetted, complex-valued, heavy-quark potential embedded in a realistic, hydrodynamically evolving medium background. We find that the lattice-vetted functional form and temperature dependence of the proper heavy-quark potential dramatically reduces the dependence of the yields on parameters other than the temperature evolution, strengthening the picture of bottomonium as QGP thermometer. Our results also show improved agreement between computed yields and experimental data produced in RHIC 200 GeV /nucleon collisions. For LHC 2.76 TeV /nucleon collisions, the excited states, whose suppression has been used as a vital sign for quark-gluon-plasma production in a heavy-ion collision, are reproduced better than previous perturbatively-motivated potential models; however, at the highest LHC energies our estimates for bottomonium suppression begin to underestimate the data. Possible paths to remedy this situation are discussed.

Nuclear Propulsion through Direct Conversion of Fusion Energy: The Fusion Driven Rocket

NASA Technical Reports Server (NTRS)

Slough, John; Pancotti, Anthony; Kirtley, David; Pihl, Christopher; Pfaff, Michael

2012-01-01

The future of manned space exploration and development of space depends critically on the creation of a dramatically more proficient propulsion architecture for in-space transportation. A very persuasive reason for investigating the applicability of nuclear power in rockets is the vast energy density gain of nuclear fuel when compared to chemical combustion energy. Current nuclear fusion efforts have focused on the generation of electric grid power and are wholly inappropriate for space transportation as the application of a reactor based fusion-electric system creates a colossal mass and heat rejection problem for space application.

Nanostructures: Physics and Technology. 7th International Symposium. St. Petersburg, Russia, June 14-18, 1999 Proceedings

DTIC Science & Technology

1999-06-18

functional theory [8]. The Hamiltonian (Ĥ↑ and Ĥ↓ for spin ↑ and spin ↓ electrons, respectively) is given by: Ĥ↑(↓) = − 2 2 ∇ [ 1 m∗(r) ∇ ] + Ec(r)+ µ...the rapid vanishing of the mean spin of electrons in this state. At the same time, the electron spin polarization at higher energy levels dramat...electrons with spin −1/2 than with spin +1/2, so energy relaxation will lead to a predominant population of higher energy levels by electrons with spin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liscom, W.L.

This book presents a complete graphic and statistical portrait of the dramatic shifts in global energy flows during the 1970s and the resultant transfer of economic and political power from the industrial nations to the oil-producing states. The information was extracted from government-source documents and compiled in a computer data base. Computer graphics were combined with the data base to produce over 400 full-color graphs. The energy commodities covered are oil, natural gas, coal, nuclear, and conventional electric-power generation. Also included are data on hydroelectric and geothermal power, oil shale, tar sands, and other alternative energy sources. 72 references.

Multi-scale theory-assisted nano-engineering of plasmonic-organic hybrid electro-optic device performance

NASA Astrophysics Data System (ADS)

Elder, Delwin L.; Johnson, Lewis E.; Tillack, Andreas F.; Robinson, Bruce H.; Haffner, Christian; Heni, Wolfgang; Hoessbacher, Claudia; Fedoryshyn, Yuriy; Salamin, Yannick; Baeuerle, Benedikt; Josten, Arne; Ayata, Masafumi; Koch, Ueli; Leuthold, Juerg; Dalton, Larry R.

2018-02-01

Multi-scale (correlated quantum and statistical mechanics) modeling methods have been advanced and employed to guide the improvement of organic electro-optic (OEO) materials, including by analyzing electric field poling induced electro-optic activity in nanoscopic plasmonic-organic hybrid (POH) waveguide devices. The analysis of in-device electro-optic activity emphasizes the importance of considering both the details of intermolecular interactions within organic electro-optic materials and interactions at interfaces between OEO materials and device architectures. Dramatic improvement in electro-optic device performance-including voltage-length performance, bandwidth, energy efficiency, and lower optical losses have been realized. These improvements are critical to applications in telecommunications, computing, sensor technology, and metrology. Multi-scale modeling methods illustrate the complexity of improving the electro-optic activity of organic materials, including the necessity of considering the trade-off between improving poling-induced acentric order through chromophore modification and the reduction of chromophore number density associated with such modification. Computational simulations also emphasize the importance of developing chromophore modifications that serve multiple purposes including matrix hardening for enhanced thermal and photochemical stability, control of matrix dimensionality, influence on material viscoelasticity, improvement of chromophore molecular hyperpolarizability, control of material dielectric permittivity and index of refraction properties, and control of material conductance. Consideration of new device architectures is critical to the implementation of chipscale integration of electronics and photonics and achieving the high bandwidths for applications such as next generation (e.g., 5G) telecommunications.

Improving estimation of kinetic parameters in dynamic force spectroscopy using cluster analysis

NASA Astrophysics Data System (ADS)

Yen, Chi-Fu; Sivasankar, Sanjeevi

2018-03-01

Dynamic Force Spectroscopy (DFS) is a widely used technique to characterize the dissociation kinetics and interaction energy landscape of receptor-ligand complexes with single-molecule resolution. In an Atomic Force Microscope (AFM)-based DFS experiment, receptor-ligand complexes, sandwiched between an AFM tip and substrate, are ruptured at different stress rates by varying the speed at which the AFM-tip and substrate are pulled away from each other. The rupture events are grouped according to their pulling speeds, and the mean force and loading rate of each group are calculated. These data are subsequently fit to established models, and energy landscape parameters such as the intrinsic off-rate (koff) and the width of the potential energy barrier (xβ) are extracted. However, due to large uncertainties in determining mean forces and loading rates of the groups, errors in the estimated koff and xβ can be substantial. Here, we demonstrate that the accuracy of fitted parameters in a DFS experiment can be dramatically improved by sorting rupture events into groups using cluster analysis instead of sorting them according to their pulling speeds. We test different clustering algorithms including Gaussian mixture, logistic regression, and K-means clustering, under conditions that closely mimic DFS experiments. Using Monte Carlo simulations, we benchmark the performance of these clustering algorithms over a wide range of koff and xβ, under different levels of thermal noise, and as a function of both the number of unbinding events and the number of pulling speeds. Our results demonstrate that cluster analysis, particularly K-means clustering, is very effective in improving the accuracy of parameter estimation, particularly when the number of unbinding events are limited and not well separated into distinct groups. Cluster analysis is easy to implement, and our performance benchmarks serve as a guide in choosing an appropriate method for DFS data analysis.

Monitoring and assessing global impacts of roads and off-road vehicle traffic

USDA-ARS?s Scientific Manuscript database

Rapid increases in the number of vehicles, urban sprawl, exurban development and infrastructure development for energy and water have led to dramatic increases in both the size and extent of the global road network. Anecdotal evidence suggests that off-road vehicle traffic has also increased in many...

Research@ARL: Network Sciences

DTIC Science & Technology

2013-03-01

and Power Allocation for Minimum Energy Consumption in Consensus Networks ................ 21 Stefania Sardellitti, Sergio Barbarossa, and Ananthram...battlefield effectiveness and to ensure that Soldier performance requirements are adequately considered in technology development and system design...Operations (NCO). NCW/NCO seeks to dramatically increase mission effectiveness via robust networking for information sharing leading to shared

Caffeine Consumption Patterns and Beliefs of College Freshmen

ERIC Educational Resources Information Center

McIlvain, Gary E.; Noland, Melody P.; Bickel, Robert

2011-01-01

Background: Caffeine consumption by young people has increased dramatically over the last decade through increased coffee consumption and "energy drinks." In higher amounts, caffeine causes many adverse effects that are cause for concern. Purpose: Purposes of this study were to determine: (1) the amount of caffeine consumed by a sample…

Ninth Annual Maintenance & Operations Cost Study.

ERIC Educational Resources Information Center

American School and University, 1980

1980-01-01

School districts during 1979-80 were faced with a dramatic reallocation of maintenance and operations funds from salaries (a 25 percent reduction from that budgeted) to cover energy costs, with the balance used in a discretionary manner to purchase equipment and supplies and contract salaries as the year evolved. (Author/MLF)

The role of cross-shock potential on pickup ion shock acceleration in the framework of focused transport theory

DOE PAGES

Zuo, Pingbing; Zhang, Ming; Rassoul, Hamid K.

2013-10-03

The focused transport theory is appropriate to describe the injection and acceleration of low-energy particles at shocks as an extension of diffusive shock acceleration (DSA). In this investigation, we aim to characterize the role of cross-shock potential (CSP) originated in the charge separation across the shock ramp on pickup ion (PUI) acceleration at various types of shocks with a focused transport model. The simulation results of energy spectrum and spatial density distribution for the cases with and without CSP added in the model are compared. With sufficient acceleration time, the focused transport acceleration finally falls into the DSA regime withmore » the power-law spectral index equal to the solution of the DSA theory. The CSP can affect the shape of the spectrum segment at lower energies, but it does not change the spectral index of the final power-law spectrum at high energies. It is found that the CSP controls the injection efficiency which is the fraction of PUIs reaching the DSA regime. A stronger CSP jump results in a dramatically improved injection efficiency. Our simulation results also show that the injection efficiency of PUIs is mass-dependent, which is lower for species with a higher mass. Additionally, the CSP is able to enhance the particle reflection upstream to produce a stronger intensity spike at the shock front. Lastly, we conclude that the CSP is a non-negligible factor that affects the dynamics of PUIs at shocks.« less

Effect of distribution, interface property and density of hydrogel-embedded vertically aligned carbon nanotube arrays on the properties of a flexible solid state supercapacitor

NASA Astrophysics Data System (ADS)

Zhu, Qi; Yuan, Xietao; Zhu, Yihao; Ni, Jiangfeng; Zhang, Xiaohua; Yang, Zhaohui

2018-05-01

In this paper we fabricate a robust flexible solid-state supercapacitor (FSC) device by embedding a conductive poly(vinyl alcohol) hydrogel into aligned carbon nanotube (CNT) arrays. We carefully investigate the effect of distribution, interface properties and densification of CNTs in the gel matrix on the electrochemical properties of an FSC. The total electrochemical capacitance of the device is measured to be 227 mF cm‑3 with a maximum energy density of 0.02 mWh cm‑3, which is dramatically enhanced compared with a similar device composed of non-parallel CNTs. Additionally, controllable in situ electrochemical oxidation greatly improved the compatibility between the hydrophobic CNTs and the hydrophilic hydrogel, which decreased the resistance of the device and introduced extra pseudocapacitance. After such oxidation treatment the energy storage ability further doubled to 430 mF cm‑3 with a maximum energy density of 0.04 mWh cm‑3 . The FSCs based on densified CNT arrays exhibited a much higher volumetric capacitance of 1140 mF cm‑3 and a larger energy density of 0.1 mWh cm‑3, with a large power density of 14 mW cm‑3. All devices show excellent stability of capacitance after at least 10 000 charge–discharge cycles with a loss of less than 2%. These easy-to-assemble hybrid arrays thus potentially provide a new method for manufacturing wearable devices and implantable medical devices.

Low-Flow Liquid Desiccant Air-Conditioning: Demonstrated Performance and Cost Implications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kozubal, E.; Herrmann, L.; Deru, M.

2014-09-01

Cooling loads must be dramatically reduced when designing net-zero energy buildings or other highly efficient facilities. Advances in this area have focused primarily on reducing a building's sensible cooling loads by improving the envelope, integrating properly sized daylighting systems, adding exterior solar shading devices, and reducing internal heat gains. As sensible loads decrease, however, latent loads remain relatively constant, and thus become a greater fraction of the overall cooling requirement in highly efficient building designs, particularly in humid climates. This shift toward latent cooling is a challenge for heating, ventilation, and air-conditioning (HVAC) systems. Traditional systems typically dehumidify by firstmore » overcooling air below the dew-point temperature and then reheating it to an appropriate supply temperature, which requires an excessive amount of energy. Another dehumidification strategy incorporates solid desiccant rotors that remove water from air more efficiently; however, these systems are large and increase fan energy consumption due to the increased airside pressure drop of solid desiccant rotors. A third dehumidification strategy involves high flow liquid desiccant systems. These systems require a high maintenance separator to protect the air distribution system from corrosive desiccant droplet carryover and so are more commonly used in industrial applications and rarely in commercial buildings. Both solid desiccant systems and most high-flow liquid desiccant systems (if not internally cooled) add sensible energy which must later be removed to the air stream during dehumidification, through the release of sensible heat during the sorption process.« less

Effect of distribution, interface property and density of hydrogel-embedded vertically aligned carbon nanotube arrays on the properties of a flexible solid state supercapacitor.

PubMed

Zhu, Qi; Yuan, Xietao; Zhu, Yihao; Ni, Jiangfeng; Zhang, Xiaohua; Yang, Zhaohui

2018-05-11

In this paper we fabricate a robust flexible solid-state supercapacitor (FSC) device by embedding a conductive poly(vinyl alcohol) hydrogel into aligned carbon nanotube (CNT) arrays. We carefully investigate the effect of distribution, interface properties and densification of CNTs in the gel matrix on the electrochemical properties of an FSC. The total electrochemical capacitance of the device is measured to be 227 mF cm -3 with a maximum energy density of 0.02 mWh cm -3 , which is dramatically enhanced compared with a similar device composed of non-parallel CNTs. Additionally, controllable in situ electrochemical oxidation greatly improved the compatibility between the hydrophobic CNTs and the hydrophilic hydrogel, which decreased the resistance of the device and introduced extra pseudocapacitance. After such oxidation treatment the energy storage ability further doubled to 430 mF cm -3 with a maximum energy density of 0.04 mWh cm -3 . The FSCs based on densified CNT arrays exhibited a much higher volumetric capacitance of 1140 mF cm -3 and a larger energy density of 0.1 mWh cm -3 , with a large power density of 14 mW cm -3 . All devices show excellent stability of capacitance after at least 10 000 charge-discharge cycles with a loss of less than 2%. These easy-to-assemble hybrid arrays thus potentially provide a new method for manufacturing wearable devices and implantable medical devices.

Kansas Wind Energy Consortium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gruenbacher, Don

2015-12-31

This project addresses both fundamental and applied research problems that will help with problems defined by the DOE “20% Wind by 2030 Report”. In particular, this work focuses on increasing the capacity of small or community wind generation capabilities that would be operated in a distributed generation approach. A consortium (KWEC – Kansas Wind Energy Consortium) of researchers from Kansas State University and Wichita State University aims to dramatically increase the penetration of wind energy via distributed wind power generation. We believe distributed generation through wind power will play a critical role in the ability to reach and extend themore » renewable energy production targets set by the Department of Energy. KWEC aims to find technical and economic solutions to enable widespread implementation of distributed renewable energy resources that would apply to wind.« less

Reaction chemistry and collisional processes in multiple devices for resolving isobaric interferences in ICP-MS.

PubMed

Bandura, D R; Baranov, V I; Tanner, S D

2001-07-01

A low-level review of the fundamentals of ion-molecule interactions is presented. These interactions are used to predict the efficiencies of collisional fragmentation, energy damping and reaction for a variety of neutral gases as a function of pressure in a rf-driven collision/reaction cell. It is shown that the number of collisions increases dramatically when the ion energies are reduced to near-thermal (< 0.1 eV), because of the ion-induced dipole and ion-dipole interaction. These considerations suggest that chemical reaction can be orders of magnitude more efficient at improving the analyte signal/background ratio than can collisional fragmentation. Considerations that lead to an appropriate selection of type of gas, operating pressure, and ion energies for efficient operation of the cell for the alleviation of spectral interferences are discussed. High efficiency (large differences between reaction efficiencies of the analyte and interference ions, and concomitant suppression of secondary chemistry) might be required to optimize the chemical resolution (determination of an analyte in the presence of an isobaric interference) when using ion-molecule chemistry to suppress the interfering ion. In many instances atom transfer to the analyte, which shifts the analytical m/z by the mass of the atom transferred, provides high chemical resolution, even when the efficiency of reaction is relatively low. Examples are given of oxidation, hydroxylation, and chlorination of analyte ions (V+, Fe+, As+, Se+, Sr+, Y+, and Zr+) to improve the capability of determination of complex samples. Preliminary results are given showing O-atom abstraction by CO from CaO+ to enable the determination of Fe in high-Ca samples.

Formation of Nanosized Defective Lithium Peroxides through Si-Coated Carbon Nanotube Cathodes for High Energy Efficiency Li-O2 Batteries.

PubMed

Lin, Qi; Cui, Zhonghui; Sun, Jiyang; Huo, Hanyu; Chen, Cheng; Guo, Xiangxin

2018-06-06

The formation and decomposition of lithium peroxides (Li 2 O 2 ) during cycling is the key process for the reversible operation of lithium-oxygen batteries. The manipulation of such products from the large toroidal particles about hundreds of nanometers to the ones in the scale of tens of nanometers can improve the energy efficiency and the cycle life of the batteries. In this work, we carry out an in situ morphology tuning of Li 2 O 2 by virtue of the surface properties of the n-type Si-modified aligned carbon nanotube (CNT) cathodes. With the introduction of an n-type Si coating layer on the CNT surface, the morphology of Li 2 O 2 formed by discharge changes from large toroidal particles (∼300 nm) deposited on the pristine CNT cathodes to nanoparticles (10-20 nm) with poor crystallinity and plenty of lithium vacancies. Beneficial from such changes, the charge overpotential dramatically decreases to 0.55 V, with the charge plateau lying at 3.5 V even in the case of a high discharge capacity (3450 mA h g -1 ) being delivered, resulting in the high electrical energy efficiency approaching 80%. Such an improvement is attributed to the fact that the introduction of the n-type Si coating layer changes the surface properties of CNTs and guides the formation of nanosized amorphous-like lithium peroxides with plenty of defects. These results demonstrate that the cathode surface properties play an important role in the formation of products formed during the cycle, providing inspiration to design superior cathodes for the Li-O 2 cells.

Analysis of group-velocity dispersion of high-frequency Rayleigh waves for near-surface applications

USGS Publications Warehouse

Luo, Y.; Xia, J.; Xu, Y.; Zeng, C.

2011-01-01

The Multichannel Analysis of Surface Waves (MASW) method is an efficient tool to obtain the vertical shear (S)-wave velocity profile using the dispersive characteristic of Rayleigh waves. Most MASW researchers mainly apply Rayleigh-wave phase-velocity dispersion for S-wave velocity estimation with a few exceptions applying Rayleigh-wave group-velocity dispersion. Herein, we first compare sensitivities of fundamental surface-wave phase velocities with group velocities with three four-layer models including a low-velocity layer or a high-velocity layer. Then synthetic data are simulated by a finite difference method. Images of group-velocity dispersive energy of the synthetic data are generated using the Multiple Filter Analysis (MFA) method. Finally we invert a high-frequency surface-wave group-velocity dispersion curve of a real-world example. Results demonstrate that (1) the sensitivities of group velocities are higher than those of phase velocities and usable frequency ranges are wider than that of phase velocities, which is very helpful in improving inversion stability because for a stable inversion system, small changes in phase velocities do not result in a large fluctuation in inverted S-wave velocities; (2) group-velocity dispersive energy can be measured using single-trace data if Rayleigh-wave fundamental-mode energy is dominant, which suggests that the number of shots required in data acquisition can be dramatically reduced and the horizontal resolution can be greatly improved using analysis of group-velocity dispersion; and (3) the suspension logging results of the real-world example demonstrate that inversion of group velocities generated by the MFA method can successfully estimate near-surface S-wave velocities. ?? 2011 Elsevier B.V.

The Role of the Department of Defense (DoD) in Solar Energy Research, Development and Diffusion

DTIC Science & Technology

2008-06-01

calculation: 103M gallons x $13.68 (total ownership cost) = $1.4B. 3 Another cost consideration that could be taken into account are the causalities... ownership cost of $1.4B will rise dramatically. 41 • Static structure, no moving parts; hence, no noise. • Longer life with little maintenance because of...instrument in DoD’s energy portfolio for the future. b. Solar vs . Wind: A Further Comparison In 2006, Detronics Limited, a company in Ontario, Canada

Wind for Schools: Fostering the Human Talent Supply Chain for a 20% Wind Energy Future (Poster)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baring-Gould, I.

2011-03-01

As the United States dramatically expands wind energy deployment, the industry is challenged with developing a skilled workforce and addressing public resistance. Wind Powering America's Wind for Schools project addresses these issues by: 1) Developing Wind Application Centers (WACs) at universities; WAC students assist in implementing school wind turbines and participate in wind courses. 2) Installing small wind turbines at community "host" schools. 3) Implementing teacher training with interactive curricula at each host school.

Crossed-beam energy transfer: polarization effects and evidence of saturation

NASA Astrophysics Data System (ADS)

Turnbull, D.; Colaïtis, A.; Follett, R. K.; Palastro, J. P.; Froula, D. H.; Michel, P.; Goyon, C.; Chapman, T.; Divol, L.; Kemp, G. E.; Mariscal, D.; Patankar, S.; Pollock, B. B.; Ross, J. S.; Moody, J. D.; Tubman, E. R.; Woolsey, N. C.

2018-05-01

Recent results on crossed-beam energy transfer are presented. Wavelength tuning was used to vary the amount of energy transfer between two beams in a quasi-stationary plasma with carefully controlled conditions. The amount of transfer agreed well with calculations assuming linear ion acoustic waves (IAWs) with amplitudes up to δ n/n≈ 0.015. Increasing the initial probe intensity to access larger IAW amplitudes for otherwise fixed conditions yields evidence of saturation. The ability to manipulate a beam's polarization, which results from the anisotropic nature of the interaction, is revisited; an example is provided to demonstrate how polarization effects in a multibeam situation can dramatically enhance the expected amount of energy transfer.

Revolution Now: The Future Arrives for Four Clean Energy Technologies

DOE R&D Accomplishments Database

Tillemann, Levi; Beck, Fredric; Brodrick, James; Brown, Austin; Feldman, David; Nguyen, Tien; Ward, Jacob

2013-09-17

For decades, America has anticipated the transformational impact of clean energy technologies. But even as costs fell and technology matured, a clean energy revolution always seemed just out of reach. Critics often said a clean energy future would "always be five years away." This report focuses on four technology revolutions that are here today. In the last five years they have achieved dramatic reductions in cost and this has been accompanied by a surge in consumer, industrial and commercial deployment. Although these four technologies still represent a small percentage of their total market, they are growing rapidly. The four key technologies this report focuses on are: onshore wind power, polysilicon photovoltaic modules, LED lighting, and electric vehicles.

From Ions to Wires to the Grid: The Transformational Science of LANL Research in High-Tc Superconducting Tapes and Electric Power Applications

ScienceCinema

Marken, Ken

2018-01-09

The Department of Energy (DOE) Office of Electricity Delivery and Energy Reliability (OE) has been tasked to lead national efforts to modernize the electric grid, enhance security and reliability of the energy infrastructure, and facilitate recovery from disruptions to energy supplies. LANL has pioneered the development of coated conductors – high-temperature superconducting (HTS) tapes – which permit dramatically greater current densities than conventional copper cable, and enable new technologies to secure the national electric grid. Sustained world-class research from concept, demonstration, transfer, and ongoing industrial support has moved this idea from the laboratory to the commercial marketplace.

Heavy Metal-Free Tannin from Bark for Sustainable Energy Storage.

PubMed

Mukhopadhyay, Alolika; Jiao, Yucong; Katahira, Rui; Ciesielski, Peter N; Himmel, Michael; Zhu, Hongli

2017-12-13

A novel renewable cathode made from earth abundant, low-cost materials can contribute to the intermittent storage needs of renewable energy-based society. In this work, we report for the first-time tannin from Nature as a cathode material. Our approach exploits the charge storage mechanism of the redox active quinone moiety. Tannins extracted from tree bark using environmental friendly aqueous solvents have the highest phenol content (5.56 mol g -1 ) among all the natural phenolic biopolymers, 5000 times higher than lignin. Tannins coupled with a conductive polymer polypyrrole acquire high specific capacitance values of 370 F g -1 at 0.5 A g -1 as well as excellent rate performance of 196 F g -1 at 25 A g -1 . Additionally, we employed carbonized wood as an electrode substrate to produce a sustainable electrochemical device with dramatically improved performance compared to conventional devices. The high surface area provided by the well-aligned, cellular porosity of wood-derived substrate combined with the high mobility of ions and electrons in the carbonized cell walls and deposited tannin can achieve an areal capacitance of 4.6 F cm -2 at 1 mA cm -2 , which is 1.5 times higher than activated wood carbon.

GPUmotif: An Ultra-Fast and Energy-Efficient Motif Analysis Program Using Graphics Processing Units

PubMed Central

Zandevakili, Pooya; Hu, Ming; Qin, Zhaohui

2012-01-01

Computational detection of TF binding patterns has become an indispensable tool in functional genomics research. With the rapid advance of new sequencing technologies, large amounts of protein-DNA interaction data have been produced. Analyzing this data can provide substantial insight into the mechanisms of transcriptional regulation. However, the massive amount of sequence data presents daunting challenges. In our previous work, we have developed a novel algorithm called Hybrid Motif Sampler (HMS) that enables more scalable and accurate motif analysis. Despite much improvement, HMS is still time-consuming due to the requirement to calculate matching probabilities position-by-position. Using the NVIDIA CUDA toolkit, we developed a graphics processing unit (GPU)-accelerated motif analysis program named GPUmotif. We proposed a “fragmentation" technique to hide data transfer time between memories. Performance comparison studies showed that commonly-used model-based motif scan and de novo motif finding procedures such as HMS can be dramatically accelerated when running GPUmotif on NVIDIA graphics cards. As a result, energy consumption can also be greatly reduced when running motif analysis using GPUmotif. The GPUmotif program is freely available at http://sourceforge.net/projects/gpumotif/ PMID:22662128

High gain solar photovoltaics

NASA Astrophysics Data System (ADS)

MacDonald, B.; Finot, M.; Heiken, B.; Trowbridge, T.; Ackler, H.; Leonard, L.; Johnson, E.; Chang, B.; Keating, T.

2009-08-01

Skyline Solar Inc. has developed a novel silicon-based PV system to simultaneously reduce energy cost and improve scalability of solar energy. The system achieves high gain through a combination of high capacity factor and optical concentration. The design approach drives innovation not only into the details of the system hardware, but also into manufacturing and deployment-related costs and bottlenecks. The result of this philosophy is a modular PV system whose manufacturing strategy relies only on currently existing silicon solar cell, module, reflector and aluminum parts supply chains, as well as turnkey PV module production lines and metal fabrication industries that already exist at enormous scale. Furthermore, with a high gain system design, the generating capacity of all components is multiplied, leading to a rapidly scalable system. The product design and commercialization strategy cooperate synergistically to promise dramatically lower LCOE with substantially lower risk relative to materials-intensive innovations. In this paper, we will present the key design aspects of Skyline's system, including aspects of the optical, mechanical and thermal components, revealing the ease of scalability, low cost and high performance. Additionally, we will present performance and reliability results on modules and the system, using ASTM and UL/IEC methodologies.

GPUmotif: an ultra-fast and energy-efficient motif analysis program using graphics processing units.

PubMed

Zandevakili, Pooya; Hu, Ming; Qin, Zhaohui

2012-01-01

Computational detection of TF binding patterns has become an indispensable tool in functional genomics research. With the rapid advance of new sequencing technologies, large amounts of protein-DNA interaction data have been produced. Analyzing this data can provide substantial insight into the mechanisms of transcriptional regulation. However, the massive amount of sequence data presents daunting challenges. In our previous work, we have developed a novel algorithm called Hybrid Motif Sampler (HMS) that enables more scalable and accurate motif analysis. Despite much improvement, HMS is still time-consuming due to the requirement to calculate matching probabilities position-by-position. Using the NVIDIA CUDA toolkit, we developed a graphics processing unit (GPU)-accelerated motif analysis program named GPUmotif. We proposed a "fragmentation" technique to hide data transfer time between memories. Performance comparison studies showed that commonly-used model-based motif scan and de novo motif finding procedures such as HMS can be dramatically accelerated when running GPUmotif on NVIDIA graphics cards. As a result, energy consumption can also be greatly reduced when running motif analysis using GPUmotif. The GPUmotif program is freely available at http://sourceforge.net/projects/gpumotif/

CsI Calorimeter for a Compton-Pair Telescope

NASA Astrophysics Data System (ADS)

Grove, Eric J.

We propose to build and test a hodoscopic CsI(Tl) scintillating-crystal calorimeter for a medium-energy γ-ray Compton and pair telescope. The design and technical approach for this calorimeter relies deeply on heritage from the Fermi LAT CsI Calorimeter, but it dramatically improves the low-energy performance of that design by reading out the scintillation light with silicon photomultipliers (SiPMs), making the technology developed for Fermi applicable in the Compton regime. While such a hodoscopic calorimeter is useful for an entire class of medium-energy γ-ray telescope designs, we propose to build it explicitly to support beam tests and balloon flight of the Proto-ComPair telescope, the development and construction of which was funded in a four-year APRA program beginning in 2015 ("ComPair: Steps to a Medium Energy γ-ray Mission" with PI J. McEnery of GSFC). That award did not include funding for its CsI calorimeter subsystem, and this proposal is intended to cover that gap. ComPair is a MIDEX-class instrument concept to perform a high-sensitivity survey of the γ-ray sky from 0.5 MeV to 500 MeV. ComPair is designed to provide a dramatic increase in sensitivity relative to previous instruments in this energy range (predominantly INTEGRAL/SPI and Compton COMPTEL), with the same transformative sensitivity increase - and corresponding scientific return- that the Fermi Large Area Telescope provided relative to Compton EGRET. To enable transformative science over a broad range of MeV energies and with a wide field of view, ComPair is a combined Compton telescope and pair telescope employing a silicon-strip tracker (for Compton scattering and pair conversion and tracking) and a solid-state CdZnTe calorimeter (for Compton absorption) and CsI calorimeter (for pair calorimetry), surrounded by a plastic scintillator anti-coincidence detector. Under the current proposal, we will complete the detailed design, assembly, and test of the CsI calorimeter for the risk-reduction prototype telescope, Proto-ComPair. We will: 1. Purchase CsI(Tl) crystals, Silicon Photomultipliers (SiPMs), and components for the analog and digital readout of the SiPMs; 2. Assemble and test Crystal Detector Elements (CDEs) from crystals, SiPMs and optical wrap; 3. Assemble and test analog and digital front-end and readout control boards; 4. Fabricate the mechanical structure that supports and contains the CDEs and electronics boards; and 5. Assemble and test the CsI calorimeter, and integrate it with the remainder of the Proto-ComPair subsystems. The PI team for this proposal conceived, designed, developed, assembled, tested, and currently operates the LAT calorimeter and is uniquely qualified to leverage the experience gained from that effort for ComPair.

Artificial intelligence guides system's best practices, cutting costs and improving services.

PubMed

1999-06-01

One for the history books. Clinical care improvement initiatives guided by a sophisticated artificial intelligence program have helped a major Virginia integrated health system make dramatic improvements in the cost and quality of its health care services. Find out how the technological innovation has earned Sentara Health System a place in the permanent collection of the Smithsonian's National Museum of American History.

Taking Human Capital Seriously: Talented Teachers in Every Classroom, Talented Principals in Every School. Principles and Recommendations for the Strategic Management of Human Capital in Public Education

ERIC Educational Resources Information Center

Consortium for Policy Research in Education, 2009

2009-01-01

The Strategic Management of Human Capital in Education Project was founded in 2008 with one goal: to improve student achievement dramatically in the 100 largest urban school districts. Unless teaching quality and principal leadership improve significantly, lasting education improvement is impossible. In policy terms, without "strategic management"…

Co-Optimization of Fuels and Engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farrell, John

2016-04-11

The Co-Optimization of Fuels and Engines (Co-Optima) initiative is a new DOE initiative focused on accelerating the introduction of affordable, scalable, and sustainable biofuels and high-efficiency, low-emission vehicle engines. The simultaneous fuels and vehicles research and development (R&D) are designed to deliver maximum energy savings, emissions reduction, and on-road vehicle performance. The initiative's integrated approach combines the previously independent areas of biofuels and combustion R&D, bringing together two DOE Office of Energy Efficiency & Renewable Energy research offices, ten national laboratories, and numerous industry and academic partners to simultaneously tackle fuel and engine research and development (R&D) to maximize energymore » savings and on-road vehicle performance while dramatically reducing transportation-related petroleum consumption and greenhouse gas (GHG) emissions. This multi-year project will provide industry with the scientific underpinnings required to move new biofuels and advanced engine systems to market faster while identifying and addressing barriers to their commercialization. This project's ambitious, first-of-its-kind approach simultaneously tackles fuel and engine innovation to co-optimize performance of both elements and provide dramatic and rapid cuts in fuel use and emissions. This presentation provides an overview of the initiative and reviews recent progress focused on both advanced spark-ignition and compression-ignition approaches.« less

CLAS g10 Analysis on Single Photopion Productions from Deuterium

NASA Astrophysics Data System (ADS)

Chen, Wei

2006-04-01

Photopion productions from nucleons are essential probes of the transition from meson-nucleon degrees of freedom to quark-gluon degrees of freedom in exclusive processes. The cross sections of these processes are also advantageous, for the investigation of the oscillatory behavior around the quark counting prediction, since they decrease relatively slower with energy compared with other photon-induced processes. Recent data from JLab experiment E94-104 [1,2] show dramatic change in the scaled differential cross-section from the γn ->&-circ;p and γp ->&+circ;n processes in the center of mass energy between 1.8 GeV to about 2.4 GeV. We are carrying out a CLAS approved analysis [3] of the JLab CLAS g10 data on the γn ->&-circ;p to investigate this dramatic behavior in much finer photon energy bins. Furthermore, the angular dependence of the scaling behavior for this process will also be studied in detail. We will report the status of the analysis in this presentation. References: [1] L.Y. Zhu et al., Phys. Rev. Lett. 91, 022003 (2003).[2] L.Y. Zhu et al., Phys. Rev. C 71, 044603 (2005); nucl-ex/0409018.[3] http://www.tunl.duke.edu/˜mep/clas/caapion.pdf

Insights on dramatic radial fluctuations in track formation by energetic ions

DOE PAGES

Sachan, Ritesh; Lang, Maik; Trautmann, Christina; ...

2016-06-02

We discuss the insights on the unexpected dramatic radial variations in the ion tracks formed by energetic ion (2.3 GeV 208Pb) irradiation at a constant electronic energy-loss (~42 keV/nm) in pyrochlore structured Gd 2TiZrO 7. Though previous studies have shown track formation and average track diameter measurements, this work brings further clarity on why quantitative analysis of ion track formation in Gd 2Ti xZr (1-x)O 7 systems can be more complicated than the currently accepted behavior for ion tracks. The ion track profile is usually considered to be diametrically uniform at constant values of the electronic energy-loss. This study showsmore » the diameter variations to be as large as ~40% within an extremely short incremental track length of ~20 nm. Our molecular dynamics simulations show that these fluctuations in diameter of amorphous core and overall track diameter are attributed to (i) the stochastic nature of inelastic energy loss along the track and (ii) the random substitution of Ti atoms by Zr atoms on the B-site in the pyrochlore lattice. Furthermore, the partial substitution of Ti by Zr increases the favorability of the defect-fluorite structure formation over amorphous phase stochastically, by introducing localized inhomogeneity in atomic structure, density and strain.« less

Insights on dramatic radial fluctuations in track formation by energetic ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sachan, Ritesh; Lang, Maik; Trautmann, Christina

We discuss the insights on the unexpected dramatic radial variations in the ion tracks formed by energetic ion (2.3 GeV 208Pb) irradiation at a constant electronic energy-loss (~42 keV/nm) in pyrochlore structured Gd 2TiZrO 7. Though previous studies have shown track formation and average track diameter measurements, this work brings further clarity on why quantitative analysis of ion track formation in Gd 2Ti xZr (1-x)O 7 systems can be more complicated than the currently accepted behavior for ion tracks. The ion track profile is usually considered to be diametrically uniform at constant values of the electronic energy-loss. This study showsmore » the diameter variations to be as large as ~40% within an extremely short incremental track length of ~20 nm. Our molecular dynamics simulations show that these fluctuations in diameter of amorphous core and overall track diameter are attributed to (i) the stochastic nature of inelastic energy loss along the track and (ii) the random substitution of Ti atoms by Zr atoms on the B-site in the pyrochlore lattice. Furthermore, the partial substitution of Ti by Zr increases the favorability of the defect-fluorite structure formation over amorphous phase stochastically, by introducing localized inhomogeneity in atomic structure, density and strain.« less

Pharmacophore-Based Similarity Scoring for DOCK

PubMed Central

2015-01-01

Pharmacophore modeling incorporates geometric and chemical features of known inhibitors and/or targeted binding sites to rationally identify and design new drug leads. In this study, we have encoded a three-dimensional pharmacophore matching similarity (FMS) scoring function into the structure-based design program DOCK. Validation and characterization of the method are presented through pose reproduction, crossdocking, and enrichment studies. When used alone, FMS scoring dramatically improves pose reproduction success to 93.5% (∼20% increase) and reduces sampling failures to 3.7% (∼6% drop) compared to the standard energy score (SGE) across 1043 protein–ligand complexes. The combined FMS+SGE function further improves success to 98.3%. Crossdocking experiments using FMS and FMS+SGE scoring, for six diverse protein families, similarly showed improvements in success, provided proper pharmacophore references are employed. For enrichment, incorporating pharmacophores during sampling and scoring, in most cases, also yield improved outcomes when docking and rank-ordering libraries of known actives and decoys to 15 systems. Retrospective analyses of virtual screenings to three clinical drug targets (EGFR, IGF-1R, and HIVgp41) using X-ray structures of known inhibitors as pharmacophore references are also reported, including a customized FMS scoring protocol to bias on selected regions in the reference. Overall, the results and fundamental insights gained from this study should benefit the docking community in general, particularly researchers using the new FMS method to guide computational drug discovery with DOCK. PMID:25229837

Control algorithms for aerobraking in the Martian atmosphere

NASA Technical Reports Server (NTRS)

Ward, Donald T.; Shipley, Buford W., Jr.

1991-01-01

The Analytic Predictor Corrector (APC) and Energy Controller (EC) atmospheric guidance concepts were adapted to control an interplanetary vehicle aerobraking in the Martian atmosphere. Changes are made to the APC to improve its robustness to density variations. These changes include adaptation of a new exit phase algorithm, an adaptive transition velocity to initiate the exit phase, refinement of the reference dynamic pressure calculation and two improved density estimation techniques. The modified controller with the hybrid density estimation technique is called the Mars Hybrid Predictor Corrector (MHPC), while the modified controller with a polynomial density estimator is called the Mars Predictor Corrector (MPC). A Lyapunov Steepest Descent Controller (LSDC) is adapted to control the vehicle. The LSDC lacked robustness, so a Lyapunov tracking exit phase algorithm is developed to guide the vehicle along a reference trajectory. This algorithm, when using the hybrid density estimation technique to define the reference path, is called the Lyapunov Hybrid Tracking Controller (LHTC). With the polynomial density estimator used to define the reference trajectory, the algorithm is called the Lyapunov Tracking Controller (LTC). These four new controllers are tested using a six degree of freedom computer simulation to evaluate their robustness. The MHPC, MPC, LHTC, and LTC show dramatic improvements in robustness over the APC and EC.

Organizational Change. Symposium 11. [Concurrent Symposium Session at AHRD Annual Conference, 2000.

ERIC Educational Resources Information Center

2000

This packet contains three papers from a symposium on organizational change. The first paper, "Kaizen Blitz: Rapid Learning to Facilitate Immediate Organizational Improvements" (Robert B. Gudgel, Fred C. Feitler), describes rapid and dramatic improvement in the organizational performance of a manufacturing firm after use of a series of…

Improving the Education of At-Risk Students. A System of Checks and Balances.

ERIC Educational Resources Information Center

Murphy, John A.

During the last five years, the Prince George's County (Maryland) public school system has brought about dramatic improvements in the academic achievement of at-risk students, offering strong evidence that public education can succeed for all children. This report describes how Prince George's County accomplished this turnaround through a process…

Using Inspections to Improve the Quality of Product Documentation and Code.

ERIC Educational Resources Information Center

Zuchero, John

1995-01-01

Describes how, by adapting software inspections to assess documentation and code, technical writers can collaborate with development personnel, editors, and customers to dramatically improve both the quality of documentation and the very process of inspecting that documentation. Notes that the five steps involved in the inspection process are:…

Improving Student Performance through Computer-Based Assessment: Insights from Recent Research.

ERIC Educational Resources Information Center

Ricketts, C.; Wilks, S. J.

2002-01-01

Compared student performance on computer-based assessment to machine-graded multiple choice tests. Found that performance improved dramatically on the computer-based assessment when students were not required to scroll through the question paper. Concluded that students may be disadvantaged by the introduction of online assessment unless care is…

A Perspective on Primary Prevention in the Earliest Years.

ERIC Educational Resources Information Center

Richmond, Julius B.

The decade of the 70's has seen significant improvements in child health and dramatic insights into the biological, psychological, and social factors influencing children's growth and development. Four of the six major gains in health status listed in the Surgeon General's Report on Health Promotion and Disease Prevention relate to improvements in…

New research and tools lead to improved earthquake alerting protocols

USGS Publications Warehouse

Wald, David J.

2009-01-01

What’s the best way to get alerted about the occurrence and potential impact of an earthquake? The answer to that question has changed dramatically of late, in part due to improvements in earthquake science, and in part by the implementation of new research in the delivery of earthquake information

Challenges in Building Usable Knowledge in Education

ERIC Educational Resources Information Center

Hedges, Larry V.

2018-01-01

The scientific rigor of education research has improved dramatically since the year 2000. Much of the credit for this improvement is deserved by Institute of Education Sciences (IES) policies that helped create a demand for rigorous research; increased human capital capacity to carry out such work; provided funding for the work itself; and…

A Better Blend: A Vision for Boosting Student Outcomes with Digital Learning

ERIC Educational Resources Information Center

Public Impact, 2013

2013-01-01

Blended learning that combines digital instruction with live, accountable teachers holds unique promise to improve student outcomes dramatically. Schools will not realize this promise at large scale with technology improvements alone, though, or with technology and today's typical teaching roles. This brief explains how schools can use blended…

Real Leaders, Real Schools: Stories of Success against Enormous Odds

ERIC Educational Resources Information Center

Leader, Gerald C.

2008-01-01

"Real Leaders, Real Schools" tells the stories of five urban public school principals who led their schools through profound and transformative changes. In each of these cases, their efforts resulted in dramatic improvements in student achievement--improvements that occurred within the current environment of high-stakes tests. The revealing and…

Resource- and Approach-Driven Multidimensional Change: Three-Year Effects of School Improvement Grants

ERIC Educational Resources Information Center

Sun, Min; Penner, Emily K.; Loeb, Susanna

2017-01-01

Hoping to spur dramatic school turnaround, the federal government channeled resources to the country's lowest-performing schools through School Improvement Grants (SIG). However, prior research on SIG effectiveness is limited and focuses primarily on student achievement. This study uses a difference-in-differences strategy to estimate program…

The Benwood Plan: A Lesson in Comprehensive Teacher Reform

ERIC Educational Resources Information Center

Silva, Elena

2008-01-01

Hamilton County, Tennessee, engaged in a multi-year effort to improve teaching in a group of eight central city elementary schools. This reform, known as the Benwood Initiative, was funded with $5 million from the Chattanooga-based Benwood Foundation. Student achievement improved dramatically as a result of this initiative. The Benwood successes…

Mild Deoxygenation of Sulfoxides over Plasmonic Molybdenum Oxide Hybrid with Dramatic Activity Enhancement under Visible Light.

PubMed

Kuwahara, Yasutaka; Yoshimura, Yukihiro; Haematsu, Kohei; Yamashita, Hiromi

2018-06-17

Harvesting solar light to boost commercially important organic synthesis still remains a challenge. Coupling of conventional noble metal catalysts with plasmonic oxide materials which exhibit intense plasmon absorption in the visible light region is a promising option for efficient solar energy utilization in catalysis. Herein we for the first time demonstrate that plasmonic hydrogen molybdenum bronze coupled with Pt nanoparticles (Pt/H x MoO 3-y ) shows a high catalytic performance in the deoxygenation of sulfoxides with 1 atm H 2 at room temperature, with dramatic activity enhancement under visible light irradiation relative to dark condition. The plasmonic molybdenum oxide hybrids with strong plasmon resonance peaks pinning at around 556 nm are obtained via a facile H-spillover process. Pt/H x MoO 3-y hybrid provides excellent selectivity for the deoxygenation of various sulfoxides as well as pyridine N-oxides, in which drastically improved catalytic efficiencies are obtained under the irradiation of visible light. Comprehensive analyses reveal that oxygen vacancies massively introduced via a H-spillover process are the main active sites, and reversible redox property of Mo atoms and strong plasmonic absorption play key roles in this reaction. The catalytic system works under extremely mild conditions and can boost the reaction by the assist of visible light, offering an ultimately greener protocol to produce sulfides from sulfoxides. Our findings may open up a new strategy for designing plasmon-based catalytic systems that can harness visible light efficiently.

Detection of significant variation in acoustic output of an electromagnetic lithotriptor.

PubMed

Pishchalnikov, Yuri A; McAteer, James A; Vonderhaar, R Jason; Pishchalnikova, Irina V; Williams, James C; Evan, Andrew P

2006-11-01

We describe the observation of significant instability in the output of an electromagnetic lithotriptor. This instability had a form that was not detected by routine assessment, but rather was observed only by collecting many consecutive shock waves in nonstop regimen. A Dornier DoLi-50 lithotriptor used exclusively for basic research was tested and approved by the regional technician. This assessment included hydrophone measures at select power levels with the collection of about 25 shock waves per setting. Subsequent laboratory characterization used a fiberoptic hydrophone and storage oscilloscope for data acquisition. Waveforms were collected nonstop for hundreds of pulses. Output was typically stable for greater than 1,000 shock waves but substantial fluctuations in acoustic pressures were also observed. For example, output at power level 3 (mean peak positive acoustic pressure +/- SD normally 44 +/- 2 MPa) increased dramatically to greater than 50 MPa or decreased significantly to approximately 30 MPa for hundreds of shock waves. The cause of instability was eventually traced to a faulty lithotriptor power supply. Instability in lithotriptor acoustic output can occur and it may not be detected by routine assessment. Collecting waveforms in a nonstop regimen dramatically increases sampling size, improving the detection of instability. Had the instability that we observed occurred during patient treatment, the energy delivered may well have exceeded the planned dose. Since the potential for adverse effects in lithotripsy increases as the dose is increased, it would be valuable to develop ways to better monitor the acoustic output of lithotriptors.

Self Assembled Dipole Monolayers on CNTs: Effect on Transport and Charge Collection

NASA Astrophysics Data System (ADS)

Cook, Alexander; Lee, Bumsu; Kuznetsov, Alexander; Podzorov, Vitaly; Zakhidov, Anvar

2010-03-01

We propose a method of quickly and dramatically increasing the conductivity of carbon nanotubes via growth of a self assembled monolayer (SAM) of fluoroalkyl trichlorosilane dipoles following the method demonstrated with organic semiconductors in [1,2]. Growth of a SAM on carbon nanotubes results in a strong p-type doping which improves the conductivity by a factor of two or more. Additionally, this doping is nonvolatile and persists in high vacuum and inert atmospheres. Improvements to conductivity are most dramatic in the case of predominantly semi-conducting, single walled carbon nanotubes (SWCNT) due to the remarkable introduction of about 1.2e14 holes/sq. cm, but this method is also an effective means to improve metallic, multi-walled carbon nanotubes (MWCNT). We will demonstrate improvement of transport and charge collection properties of both SWCNTs and MWCNTs by these SAM coatings in FETs and also in organic photovoltaic solar cells and in OLEDs. [1] M. F. Calhoun et al. Nature Materials 7, 84 - 89 (2008). [2] C. Y. Kao et al. Adv. Func. Mater. 19, 1 (2009).

Current state and future direction of computer systems at NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Rogers, James L. (Editor); Tucker, Jerry H. (Editor)

1992-01-01

Computer systems have advanced at a rate unmatched by any other area of technology. As performance has dramatically increased there has been an equally dramatic reduction in cost. This constant cost performance improvement has precipitated the pervasiveness of computer systems into virtually all areas of technology. This improvement is due primarily to advances in microelectronics. Most people are now convinced that the new generation of supercomputers will be built using a large number (possibly thousands) of high performance microprocessors. Although the spectacular improvements in computer systems have come about because of these hardware advances, there has also been a steady improvement in software techniques. In an effort to understand how these hardware and software advances will effect research at NASA LaRC, the Computer Systems Technical Committee drafted this white paper to examine the current state and possible future directions of computer systems at the Center. This paper discusses selected important areas of computer systems including real-time systems, embedded systems, high performance computing, distributed computing networks, data acquisition systems, artificial intelligence, and visualization.

Charge Carrier Hopping Dynamics in Homogeneously Broadened PbS Quantum Dot Solids.

PubMed

Gilmore, Rachel H; Lee, Elizabeth M Y; Weidman, Mark C; Willard, Adam P; Tisdale, William A

2017-02-08

Energetic disorder in quantum dot solids adversely impacts charge carrier transport in quantum dot solar cells and electronic devices. Here, we use ultrafast transient absorption spectroscopy to show that homogeneously broadened PbS quantum dot arrays (σ hom 2 :σ inh 2 > 19:1, σ inh /k B T < 0.4) can be realized if quantum dot batches are sufficiently monodisperse (δ ≲ 3.3%). The homogeneous line width is found to be an inverse function of quantum dot size, monotonically increasing from ∼25 meV for the largest quantum dots (5.8 nm diameter/0.92 eV energy) to ∼55 meV for the smallest (4.1 nm/1.3 eV energy). Furthermore, we show that intrinsic charge carrier hopping rates are faster for smaller quantum dots. This finding is the opposite of the mobility trend commonly observed in device measurements but is consistent with theoretical predictions. Fitting our data to a kinetic Monte Carlo model, we extract charge carrier hopping times ranging from 80 ps for the smallest quantum dots to over 1 ns for the largest, with the same ethanethiol ligand treatment. Additionally, we make the surprising observation that, in slightly polydisperse (δ ≲ 4%) quantum dot solids, structural disorder has a greater impact than energetic disorder in inhibiting charge carrier transport. These findings emphasize how small improvements in batch size dispersity can have a dramatic impact on intrinsic charge carrier hopping behavior and will stimulate further improvements in quantum dot device performance.

The Art of Photoelectron Spectroscopy, from Micro to Nano

NASA Astrophysics Data System (ADS)

Rotenberg, Eli

Angle-resolved photoemission spectroscopy (ARPES) was developed for the determination of the electronic bandstructure of solids. In the last 20 years, ARPES has become nearly unlimited with respect to instrumental resolution, and therefore able to illuminate more subtle electronic aspects, such as ground-state symmetry breaking and the many-body interactions (MBIs) that characterize ground states such as superconductivity. These MBIs involve exchange of momentum among electrons or with excitations such as phonons, and can therefore couple to nanoscale structures. By controlling the structure at the nanoscale, we can therefore hope to control or enhance the ground state properties of materials through nanoscale engineering. This dream has motivated the development of nanoscale ARPES (nanoARPES) machines that are now coming online worldwide. After a brief overview, I will show the latest results from the new nanoARPES endstation at the MAESTRO facility (Microscopic and Electronic Structure Observatory), a new user beamline commissioned this year at the Advanced Light Source (ALS). We achieved routine operation at spatial resolution around 120 nm, and expect improvement down to 50 nm or better. Examples will include graphene and 2D-metal-chalcogenide heterostructures. I will also discuss the prospects for dramatic improvements expected as new diffraction-limited light sources such as the ALS-U project are realized. Work performed at the Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

Acceleration of saddle-point searches with machine learning.

PubMed

Peterson, Andrew A

2016-08-21

In atomistic simulations, the location of the saddle point on the potential-energy surface (PES) gives important information on transitions between local minima, for example, via transition-state theory. However, the search for saddle points often involves hundreds or thousands of ab initio force calls, which are typically all done at full accuracy. This results in the vast majority of the computational effort being spent calculating the electronic structure of states not important to the researcher, and very little time performing the calculation of the saddle point state itself. In this work, we describe how machine learning (ML) can reduce the number of intermediate ab initio calculations needed to locate saddle points. Since machine-learning models can learn from, and thus mimic, atomistic simulations, the saddle-point search can be conducted rapidly in the machine-learning representation. The saddle-point prediction can then be verified by an ab initio calculation; if it is incorrect, this strategically has identified regions of the PES where the machine-learning representation has insufficient training data. When these training data are used to improve the machine-learning model, the estimates greatly improve. This approach can be systematized, and in two simple example problems we demonstrate a dramatic reduction in the number of ab initio force calls. We expect that this approach and future refinements will greatly accelerate searches for saddle points, as well as other searches on the potential energy surface, as machine-learning methods see greater adoption by the atomistics community.

Acceleration of saddle-point searches with machine learning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peterson, Andrew A., E-mail: andrew-peterson@brown.edu

In atomistic simulations, the location of the saddle point on the potential-energy surface (PES) gives important information on transitions between local minima, for example, via transition-state theory. However, the search for saddle points often involves hundreds or thousands of ab initio force calls, which are typically all done at full accuracy. This results in the vast majority of the computational effort being spent calculating the electronic structure of states not important to the researcher, and very little time performing the calculation of the saddle point state itself. In this work, we describe how machine learning (ML) can reduce the numbermore » of intermediate ab initio calculations needed to locate saddle points. Since machine-learning models can learn from, and thus mimic, atomistic simulations, the saddle-point search can be conducted rapidly in the machine-learning representation. The saddle-point prediction can then be verified by an ab initio calculation; if it is incorrect, this strategically has identified regions of the PES where the machine-learning representation has insufficient training data. When these training data are used to improve the machine-learning model, the estimates greatly improve. This approach can be systematized, and in two simple example problems we demonstrate a dramatic reduction in the number of ab initio force calls. We expect that this approach and future refinements will greatly accelerate searches for saddle points, as well as other searches on the potential energy surface, as machine-learning methods see greater adoption by the atomistics community.« less

Highly conductive electrospun carbon nanofiber/MnO2 coaxial nano-cables for high energy and power density supercapacitors

NASA Astrophysics Data System (ADS)

Zhi, Mingjia; Manivannan, Ayyakkannu; Meng, Fanke; Wu, Nianqiang

2012-06-01

This paper presents highly conductive carbon nanofiber/MnO2 coaxial cables in which individual electrospun carbon nanofibers are coated with an ultrathin hierarchical MnO2 layer. In the hierarchical MnO2 structure, an around 4 nm thick sheath surrounds the carbon nanofiber (CNF) in a diameter of 200 nm, and nano-whiskers grow radically outward from the sheath in view of the cross-section of the coaxial cables, giving a high specific surface area of MnO2. The CNFs are synthesized by electrospinning a precursor containing iron acetylacetonate (AAI). The addition of AAI not only enlarges the specific surface area of the CNF but also greatly enhances their electronic conductivity, which leads to a dramatic improvement in the specific capacitance and the rate capability of the CNF/MnO2 electrode. The AAI-CNF/MnO2 electrode shows a specific capacitance of 311 F g-1 for the whole electrode and 900 F g-1 for the MnO2 shell at a scan rate of 2 mV s-1. Good cycling stability, high energy density (80.2 Wh kg-1) and high power density (57.7 kW kg-1) are achieved. This work indicates that high electronic conductivity of the electrode material is crucial to achieving high power and energy density for pseudo-supercapacitors.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vimmerstedt, Laura; Brown, Austin; Newes, Emily

The transportation sector is changing, influenced by concurrent, ongoing, dynamic trends that could dramatically affect the future energy landscape, including effects on the potential for greenhouse gas emissions reductions. Battery cost reductions and improved performance coupled with a growing number of electric vehicle model offerings are enabling greater battery electric vehicle market penetration, and advances in fuel cell technology and decreases in hydrogen production costs are leading to initial fuel cell vehicle offerings. Radically more efficient vehicles based on both conventional and new drivetrain technologies reduce greenhouse gas emissions per vehicle-mile. Net impacts also depend on the energy sources usedmore » for propulsion, and these are changing with increased use of renewable energy and unconventional fossil fuel resources. Connected and automated vehicles are emerging for personal and freight transportation systems and could increase use of low- or non-emitting technologies and systems; however, the net effects of automation on greenhouse gas emissions are uncertain. The longstanding trend of an annual increase in transportation demand has reversed for personal vehicle miles traveled in recent years, demonstrating the possibility of lower-travel future scenarios. Finally, advanced biofuel pathways have continued to develop, highlighting low-carbon and in some cases carbon-negative fuel pathways. We discuss the potential for transformative reductions in petroleum use and greenhouse gas emissions through these emerging transportation-sector technologies and trends and present a Clean Transportation Sector Initiative scenario for such reductions, which are summarized in Table ES-1.« less

Potential emissions reduction in road transport sector using biofuel in developing countries

NASA Astrophysics Data System (ADS)

Liaquat, A. M.; Kalam, M. A.; Masjuki, H. H.; Jayed, M. H.

2010-10-01

Use of biofuels as transport fuel has high prospect in developing countries as most of them are facing severe energy insecurity and have strong agricultural sector to support production of biofuels from energy crops. Rapid urbanization and economic growth of developing countries have spurred air pollution especially in road transport sector. The increasing demand of petroleum based fuels and their combustion in internal combustion (IC) engines have adverse effect on air quality, human health and global warming. Air pollution causes respiratory problems, adverse effects on pulmonary function, leading to increased sickness absenteeism and induces high health care service costs, premature birth and even mortality. Production of biofuels promises substantial improvement in air quality through reducing emission from biofuel operated automotives. Some of the developing countries have started biofuel production and utilization as transport fuel in local market. This paper critically reviews the facts and prospects of biofuel production and utilization in developing countries to reduce environmental pollution and petro dependency. Expansion of biofuel industries in developing countries can create more jobs and increase productivity by non-crop marginal lands and wastelands for energy crops plantation. Contribution of India and China in biofuel industry in production and utilization can dramatically change worldwide biofuel market and leap forward in carbon cut as their automotive market is rapidly increasing with a souring proportional rise of GHG emissions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dahlburg, Jill; Corones, James; Batchelor, Donald

Fusion is potentially an inexhaustible energy source whose exploitation requires a basic understanding of high-temperature plasmas. The development of a science-based predictive capability for fusion-relevant plasmas is a challenge central to fusion energy science, in which numerical modeling has played a vital role for more than four decades. A combination of the very wide range in temporal and spatial scales, extreme anisotropy, the importance of geometric detail, and the requirement of causality which makes it impossible to parallelize over time, makes this problem one of the most challenging in computational physics. Sophisticated computational models are under development for many individualmore » features of magnetically confined plasmas and increases in the scope and reliability of feasible simulations have been enabled by increased scientific understanding and improvements in computer technology. However, full predictive modeling of fusion plasmas will require qualitative improvements and innovations to enable cross coupling of a wider variety of physical processes and to allow solution over a larger range of space and time scales. The exponential growth of computer speed, coupled with the high cost of large-scale experimental facilities, makes an integrated fusion simulation initiative a timely and cost-effective opportunity. Worldwide progress in laboratory fusion experiments provides the basis for a recent FESAC recommendation to proceed with a burning plasma experiment (see FESAC Review of Burning Plasma Physics Report, September 2001). Such an experiment, at the frontier of the physics of complex systems, would be a huge step in establishing the potential of magnetic fusion energy to contribute to the world’s energy security. An integrated simulation capability would dramatically enhance the utilization of such a facility and lead to optimization of toroidal fusion plasmas in general. This science-based predictive capability, which was cited in the FESAC integrated planning document (IPPA, 2000), represents a significant opportunity for the DOE Office of Science to further the understanding of fusion plasmas to a level unparalleled worldwide.« less

Teacher Professional Development that Makes an Impact

NASA Astrophysics Data System (ADS)

Borrego, H.; Ellins, K. K.

2012-12-01

Through four years of participation in the TeXas Earth and Space Science (TXESS) Revolution, an NSF-sponsored teacher professional development project, my knowledge of earth science and new pedagogical approaches has improved dramatically. In addition, I have received instructional materials, and learned how to access high quality online resources and use a variety of web-based tools. As a consequence, I have developed the confidence to use the TXESS model to deliver earth science professional development that makes an impact to other teachers in the Rio Grande Valley region of South Texas. In this session, I will share my experiences as an earth science professional development provider and describe how I have used my own learning to help both teachers and students become more earth science literate. Earth science test scores at the elementary and secondary level throughout South Texas are consistently low in comparison to other regional areas in the state. The majority of the teachers lack the content-knowledge, confidence, or experience to teach earth science. My background as teacher combined with the TXESS Revolution experience helped me to understand the needs of these teachers and to identify teaching resources that would be useful to them. Using educational resources provided by the TXESS Revolution I have offered professional development topics such as Energy, Geologic Time and Stratigraphy, Water and the Cryosphere, Plate Tectonics, and Climate to about 125 South Texas elementary and middle school teachers. These trainings have helped improve the content knowledge of South Texas teachers and given them tools that they can use to guide student learning through authentic scientific research. In addition to providing professional development to teachers, I have been recruited to serve as the representative of the Offshore Energy Center for South Texas. This curriculum complements the TXESS Revolution educational resources by expanding the Energy education. The partnership with Offshore Energy is financing the framework for developing more training. More than 15 school districts in South Texas will have the opportunity to participate in this program

Fundamental Performance Improvement of Microwave Kinetic Inductance Detectors for UVOIR Astrophysics

NASA Astrophysics Data System (ADS)

Mazin, Benjamin

Ultraviolet, Optical, and near-Infrared Microwave Kinetic Inductance Detectors (UVOIR MKIDs) are one of the most powerful new technologies to emerge out of the NASA APRA detectors program in the last decade. This proposal seeks to build on previous APRA grants to drastically improve the performance of UVOIR MKIDs. Like an X-ray microcalorimeter ultraviolet, optical, and near-IR (UVOIR) MKIDs are cryogenic detectors capable of detecting single photons and measuring their energy without filters or gratings. Our team has created this technology from the ground up, and fielded a 2024-pixel UVOIR MKID array on five separate observing runs at 5-m class telescopes. With 34 observing nights successfully completed and two astronomy papers published using MKID data (the first astronomy papers published using MKID data at any wavelength), UVOIR MKIDs are at TRL 5-6 for ground-based astronomy, and TRL 3 for space-based astronomy. The outstanding potential of these detectors was recognized in the recent NASA long term vision, "Enduring Quests, Daring Visions'', which recognized on page 88 that MKIDs have tremendous potential for future NASA UVOIR space missions, especially for finding Earth twins around nearby stars: "..microwave kinetic inductance detectors (MKIDs) would be a game-changing capability..''. Current UVOIR MKIDs feature array sizes in the 10-30 kpix range, energy resolution R=16 at 254 nm, ~70% pixel yield, and quantum efficiency that goes from 70% in the UV to 25% in the near-IR. These arrays, fabricated out of Titanium Nitride (TiN) on a high resistivity silicon substrate, are fully functional for ground-based science. However, our current MKIDs are far away from their theoretical limits, especially in yield (70% vs. 100%) and energy resolution (R=10 vs. R=100 at 400 nm). The yield is of especially urgent concern as missing pixels make accurate photometry difficult, especially for rapidly time variable sources like compact binaries that we have been studying. The yield is low because the reactively sputtered TiN that we make our MKIDs from is extremely sensitive to deposition conditions, and the resistivity and hence resonant frequency of the MKIDs varies dramatically across a wafer, as shown in. Our energy resolution is low because of a combination of factors related to the MKID material and the two level system (TLS) noise from our capacitors. In order to improve our current energy resolution, yield, and quantum efficiency we need to move in new directions. This proposal will focus on two main improvements: making better MKID resonator materials, and making lower noise capacitors.

Ganymede - Comparison of Voyager and Galileo Resolution

NASA Image and Video Library

1997-09-07

These images demonstrate the dramatic improvement in the resolution of pictures that NASA Galileo spacecraft returned compared to previous images of the Jupiter system. http://photojournal.jpl.nasa.gov/catalog/PIA00277

Argonne National Laboratory |

Science.gov Websites

for next-gen lithium batteries. Spotlight New ion source dramatically improves radioactive beams for Argonne's CARIBU facility A new Electron Beam Ion Source Charge Breeder operated with Argonne's CARIBU and

Learning Sustainability by Developing a Solar Dryer for Microalgae Retrieval

ERIC Educational Resources Information Center

Malheiro, Benedita; Ribeiro, Cristina; Silva, Manuel F.; Caetano, Nídia; Paulo Ferreira,; Guedes, Pedro

2015-01-01

The development of nations depends on energy consumption, which is generally based on fossil fuels. This dependency produces irreversible and dramatic effects on the environment, e.g. large greenhouse gas emissions, which in turn cause global warming and climate changes, responsible for the rise of the sea level, floods, and other extreme weather…

Indigenous and Interdependent Perspectives of Healing: Implications for Counseling and Research

ERIC Educational Resources Information Center

Yeh, Christine J.; Hunter, Carla D.; Madan-Bahel, Anvita; Chiang, Lillian; Arora, Agnes K.

2004-01-01

Because of the dramatic increases of culturally diverse individuals in the United States, indigenous perspectives of healing must be understood in the context of interdependent cultural selves. The authors present an extensive review of the literature with a focus on understanding the role of spirituality, balancing energies, close social…

Culture & Technology[TM]. [CD-ROM].

ERIC Educational Resources Information Center

2000

This three CD-ROM set is designed to integrate social studies and science. There are 1,300 lessons developed and field tested by curriculum specialists, teachers, and students over a period of 15 years. Using dramatic video, audio, and photos, students can make connections between diet and temperature, location and climate, safety and energy,…

National Trends in Sustainability Performance: Lessons for Facilities Leaders

ERIC Educational Resources Information Center

Jones, Kristy M.; Keniry, L. Julian

2009-01-01

For most facilities leaders, sustainability is nothing new. The authors have observed repeatedly over several decades that administrative and facilities staff have often taken the lead in initiating many of the most effective and visible efforts on campuses to dramatically curb energy use and waste and to contain costs, even during times of rapid…

The Conservation of Energy Concept in Ninth Grade General Science, Final Report.

ERIC Educational Resources Information Center

Shockley, William; And Others

Discussed is an instructional approach, "concept-distillation," which involves experiences, games, and puzzles that have the "distilled essence" of the basic concepts of the physical sciences. This approach is designed to impart a vivid and dramatic meaning and structure of the sciences for transfer in scientific thinking. The…

Why Cool Roofs?

ScienceCinema

Chu, Steven

2017-12-27

By installing a cool roof at DOE, the federal government and Secretary Chu are helping to educate families and businesses about the important energy and cost savings that can come with this simple, low-cost technology. Cool roofs have the potential to quickly and dramatically reduce global carbon emissions while saving money every month on consumers' electrical bills.

Pull the Weeds Before You Plant the Flowers

ERIC Educational Resources Information Center

Reeves, Douglas

2006-01-01

Educators are drowning under the weight of initiative fatigue--attempting to use the same amount of time, money, and emotional energy to accomplish more and more objectives. Eventually, each initiative added to the pile creates a dramatic decline in organizational effectiveness. As such, principals need to help their teachers by lessening the…

Weak-coupling superconductivity in a strongly correlated iron pnictide

PubMed Central

Charnukha, A.; Post, K. W.; Thirupathaiah, S.; Pröpper, D.; Wurmehl, S.; Roslova, M.; Morozov, I.; Büchner, B.; Yaresko, A. N.; Boris, A. V.; Borisenko, S. V.; Basov, D. N.

2016-01-01

Iron-based superconductors have been found to exhibit an intimate interplay of orbital, spin, and lattice degrees of freedom, dramatically affecting their low-energy electronic properties, including superconductivity. Albeit the precise pairing mechanism remains unidentified, several candidate interactions have been suggested to mediate the superconducting pairing, both in the orbital and in the spin channel. Here, we employ optical spectroscopy (OS), angle-resolved photoemission spectroscopy (ARPES), ab initio band-structure, and Eliashberg calculations to show that nearly optimally doped NaFe0.978Co0.022As exhibits some of the strongest orbitally selective electronic correlations in the family of iron pnictides. Unexpectedly, we find that the mass enhancement of itinerant charge carriers in the strongly correlated band is dramatically reduced near the Γ point and attribute this effect to orbital mixing induced by pronounced spin-orbit coupling. Embracing the true band structure allows us to describe all low-energy electronic properties obtained in our experiments with remarkable consistency and demonstrate that superconductivity in this material is rather weak and mediated by spin fluctuations. PMID:26729630

Computing Cosmic Cataclysms

NASA Technical Reports Server (NTRS)

Centrella, Joan M.

2010-01-01

The final merger of two black holes releases a tremendous amount of energy, more than the combined light from all the stars in the visible universe. This energy is emitted in the form of gravitational waves, and observing these sources with gravitational wave detectors requires that we know the pattern or fingerprint of the radiation emitted. Since black hole mergers take place in regions of extreme gravitational fields, we need to solve Einstein's equations of general relativity on a computer in order to calculate these wave patterns. For more than 30 years, scientists have tried to compute these wave patterns. However, their computer codes have been plagued by problems that caused them to crash. This situation has changed dramatically in the past few years, with a series of amazing breakthroughs. This talk will take you on this quest for these gravitational wave patterns, showing how a spacetime is constructed on a computer to build a simulation laboratory for binary black hole mergers. We will focus on the recent advances that are revealing these waveforms, and the dramatic new potential for discoveries that arises when these sources will be observed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

This factsheet describes a project that developed and demonstrated a new manufacturing-informed design framework that utilizes advanced multi-scale, physics-based process modeling to dramatically improve manufacturing productivity and quality in machining operations while reducing the cost of machined components.

Unparticle physics.

PubMed

Georgi, Howard

2007-06-01

I discuss some simple aspects of the low-energy physics of a nontrivial scale invariant sector of an effective field theory-physics that cannot be described in terms of particles. I argue that it is important to take seriously the possibility that the unparticle stuff described by such a theory might actually exist in our world. I suggest a scenario in which some details of the production of unparticle stuff can be calculated. I find that in the appropriate low-energy limit, unparticle stuff with scale dimension dU looks like a nonintegral number dU of invisible particles. Thus dramatic evidence for a nontrivial scale invariant sector could show up experimentally in missing energy distributions.

Health and Climate Impacts of Rural Residential Energy Transition in China

NASA Astrophysics Data System (ADS)

Tao, Shu; Ru, Muye; Du, Wei; Zhu, Xi; Zhong, Qirui

2017-04-01

Over the last two to three decades, energy mix in rural China transit dramatically owing to rapid socioeconomic development. It is expected that such transition can result in changes in emissions of climate forcing components and air pollutants, consequently environmental and climate impacts. Such impacts were quantified by a nationwide survey on rural residential energy consumption, compilation of a series of emission inventories, modeling of atmospheric transport of pollutants, assessment on health risk induced by exposure to ambient air pollutants, and evaluation on rural residential emission originated climate forcing components. Co-benefit of the transition on both health and climate is demonstrated.

eV-TEM: Transmission electron microscopy in a low energy cathode lens instrument.

PubMed

Geelen, Daniël; Thete, Aniket; Schaff, Oliver; Kaiser, Alexander; van der Molen, Sense Jan; Tromp, Rudolf

2015-12-01

We are developing a transmission electron microscope that operates at extremely low electron energies, 0-40 eV. We call this technique eV-TEM. Its feasibility is based on the fact that at very low electron energies the number of energy loss pathways decreases. Hence, the electron inelastic mean free path increases dramatically. eV-TEM will enable us to study elastic and inelastic interactions of electrons with thin samples. With the recent development of aberration correction in cathode lens instruments, a spatial resolution of a few nm appears within range, even for these very low electron energies. Such resolution will be highly relevant to study biological samples such as proteins and cell membranes. The low electron energies minimize adverse effects due to radiation damage. Copyright © 2015. Published by Elsevier B.V.

Planning building energy conservation research in the US

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abel, F.; LaMontagne, J.

1988-01-01

In the US, the federal government plays a key role in the development of energy conserving technologies and practices for buildings. The Office of Buildings and Community Systems (BCS) of the US Department of Energy provides federal leadership for both private and public sector activities in building energy conservation. The federal role in recent years has been largely limited to the development of technical options; behavioral and institutional factors are considered only to the extent necessary to inform the research planning process. Planning in the US requires dealing with uncertainties regarding the federal approach to energy conservation; this can change,more » often dramatically, with changes in administrations or changing economic and energy conditions. Thus federal research plans must be designed to be useful in a wide variety of circumstances. 7 refs.« less

Rapid-cycle testing cuts bed turnaround by 85%.

PubMed

2004-11-01

You can use rapid-cycle testing to try out new approaches to overcrowding much more frequently than with more traditional process improvement strategies. Improving bed turnaround notification can yield dramatic improvements. Telling staff they have to try a new process only for three days makes it easier to gain buy-in. Look for old policies that are no longer needed, yet continue to keep your staff bogged down.

Wind energy.

PubMed

Leithead, W E

2007-04-15

From its rebirth in the early 1980s, the rate of development of wind energy has been dramatic. Today, other than hydropower, it is the most important of the renewable sources of power. The UK Government and the EU Commission have adopted targets for renewable energy generation of 10 and 12% of consumption, respectively. Much of this, by necessity, must be met by wind energy. The US Department of Energy has set a goal of 6% of electricity supply from wind energy by 2020. For this potential to be fully realized, several aspects, related to public acceptance, and technical issues, related to the expected increase in penetration on the electricity network and the current drive towards larger wind turbines, need to be resolved. Nevertheless, these challenges will be met and wind energy will, very likely, become increasingly important over the next two decades. An overview of the technology is presented.

A Century of Children's Health and Well-Being. Child Trends Research Brief.

ERIC Educational Resources Information Center

Brown, Brett V.; Kinkukawa, Akemi; Michelsen, Erik; Moore, Amber; Moore, Kristin Anderson; Sugland, Barbara W.

Although the last 100 years have seen dramatic improvements in the health of U.S. children, there remain racial and ethnic disparities. This research brief presents data illustrating improvements in children's health and the need for further progress. The brief also examines new morbidities among American youth, such as obesity, early sexual…

Federal School Improvement Grants (SIGs): How Capacity and Local Conditions Matter

ERIC Educational Resources Information Center

Yatsko, Sarah; Lake, Robin; Bowen, Melissa; Cooley Nelson, Elizabeth

2015-01-01

In 2009, the federal government committed over $3 billion nationwide to help states and districts turn around their worst-performing schools. The U.S. Department of Education intended for the School Improvement Grants (SIGs) to spur dramatic change.This report looks at the results of a field study of the first-year implementation of those grants…

Tinkering toward Transformation: A Look at Federal School Improvement Grant Implementation

ERIC Educational Resources Information Center

Yatsko, Sarah; Lake, Robin; Nelson, Elizabeth Cooley; Bowen, Melissa

2012-01-01

In 2009, the federal government committed over $3 billion nationwide to help states and districts turn around their worst-performing schools. The U.S. Department of Education intended for the School Improvement Grants (SIGs) to spur dramatic change. This report looks at the results of a field study of the first-year implementation of those grants…

Changing the School Climate Is the First Step to Reform in Many Schools with Federal Improvement Grants

ERIC Educational Resources Information Center

McMurrer, Jennifer

2012-01-01

School Improvement Grants (SIGs) financed through the economic stimulus package are intended to spur dramatic change in persistently low-performing schools. Many state and local officials charged with implementing SIGs view the creation of a safe, orderly, collegial, and productive school climate as an essential step in raising student…

Power and Leader Effectiveness in Organizations: A Literature Review

DTIC Science & Technology

2008-09-01

cinema and television as dramatic, memorable verbal reprimands for poor performance or an unaccomplished mission. However, coercive power does not...character played by Michael Keaton improved American automotive plant efficiency by improving working relations between the Japanese management and...attraction between the Japanese management and the American laborers. The relational benefits translated into happier employees that were more

Crossed-beam energy transfer: polarization effects and evidence of saturation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Turnbull, D.; Colaitis, A.; Follett, R. K.

In this article, recent results on crossed-beam energy transfer are presented. Wave-length tuning was used to vary the amount of energy transfer between two beams in a quasi-stationary plasma with carefully controlled conditions. The amount of transfer agreed well with calculations assuming linear ion acoustic waves with amplitudes up to δn/n ≈ 0.015. Increasing the initial probe intensity to access larger ion acoustic wave amplitudes for otherwise fixed conditions yields evidence of saturation. The ability to manipulate a beam’s polarization, which results from the anisotropic nature of the interaction, is revisited; an example is provided to demonstrate how polarization effectsmore » in a multibeam situation can dramatically enhance the expected amount of energy transfer.« less

Crossed-beam energy transfer: polarization effects and evidence of saturation

DOE PAGES

Turnbull, D.; Colaitis, A.; Follett, R. K.; ...

2018-04-05

In this article, recent results on crossed-beam energy transfer are presented. Wave-length tuning was used to vary the amount of energy transfer between two beams in a quasi-stationary plasma with carefully controlled conditions. The amount of transfer agreed well with calculations assuming linear ion acoustic waves with amplitudes up to δn/n ≈ 0.015. Increasing the initial probe intensity to access larger ion acoustic wave amplitudes for otherwise fixed conditions yields evidence of saturation. The ability to manipulate a beam’s polarization, which results from the anisotropic nature of the interaction, is revisited; an example is provided to demonstrate how polarization effectsmore » in a multibeam situation can dramatically enhance the expected amount of energy transfer.« less

Quasiparticle Energy in a Strongly Interacting Homogeneous Bose-Einstein Condensate.

PubMed

Lopes, Raphael; Eigen, Christoph; Barker, Adam; Viebahn, Konrad G H; Robert-de-Saint-Vincent, Martin; Navon, Nir; Hadzibabic, Zoran; Smith, Robert P

2017-05-26

Using two-photon Bragg spectroscopy, we study the energy of particlelike excitations in a strongly interacting homogeneous Bose-Einstein condensate, and observe dramatic deviations from Bogoliubov theory. In particular, at large scattering length a the shift of the excitation resonance from the free-particle energy changes sign from positive to negative. For an excitation with wave number q, this sign change occurs at a≈4/(πq), in agreement with the Feynman energy relation and the static structure factor expressed in terms of the two-body contact. For a≳3/q we also see a breakdown of this theory, and better agreement with calculations based on the Wilson operator product expansion. Neither theory explains our observations across all interaction regimes, inviting further theoretical efforts.

Division of energy biosciences: Annual report and summaries of FY 1995 activities

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-04-01

The mission of the Division of Energy Biosciences is to support research that advances the fundamental knowledge necessary for the future development of biotechnologies related to the Department of Energy`s mission. The departmental civilian objectives include effective and efficient energy production, energy conservation, environmental restoration, and waste management. The Energy Biosciences program emphasizes research in the microbiological and plant sciences, as these understudied areas offer numerous scientific opportunities to dramatically influence environmentally sensible energy production and conservation. The research supported is focused on the basic mechanisms affecting plant productivity, conversion of biomass and other organic materials into fuels and chemicalsmore » by microbial systems, and the ability of biological systems to replace energy-intensive or pollutant-producing processes. The Division also addresses the increasing number of new opportunities arising at the interface of biology with other basic energy-related sciences such as biosynthesis of novel materials and the influence of soil organisms on geological processes.« less

Dramatic weight loss associated with commencing clozapine.

PubMed

Lally, John; McDonald, Colm

2011-11-08

The authors report the case of a 44-year-old man with a long history of chronic enduring schizophrenia who experienced dramatic weight loss after commencing treatment with clozapine, an antipsychotic medication characteristically associated with the greatest degree of weight gain among medical treatments for schizophrenia. He was obese with a body mass index (BMI) of 41.5 kg/m(2), but after commencing clozapine therapy he experienced an improvement in psychotic symptoms and 40% loss of his body weight attained through an altered diet and exercise regime, which resulted in him attaining a normal BMI of 24.8 kg/m(2).

AIDS Myths and Misunderstandings

MedlinePlus

... get infected. Reality: today’s medications have cut the death rate from AIDS by about 80%. They are also ... In the 1980s, there was a very high death rate from AIDS. However, medications have improved dramatically and ...

Prep-ME Software Implementation and Enhancement

DOT National Transportation Integrated Search

2017-09-01

Highway agencies across the United States are moving from empirical design procedures towards the mechanistic-empirical (ME) based pavement design. Even though the Pavement ME Design presents a new paradigm shift with several dramatic improvements, i...

Biodegradation of pentafluorosulfanyl-substituted aminophenol in Pseudomonas spp.

PubMed

Saccomanno, Marta; Hussain, Sabir; O'Connor, Neil K; Beier, Petr; Somlyay, Mate; Konrat, Robert; Murphy, Cormac D

2018-06-01

The pentafluorosulfanyl (SF 5 -) substituent conveys properties that are beneficial to drugs and agrochemicals. As synthetic methodologies improve the number of compounds containing this group will expand and these chemicals may be viewed as emerging pollutants. As many microorganisms can degrade aromatic xenobiotics, we investigated the catabolism of SF 5 -substituted aminophenols by bacteria and found that some Pseudomonas spp. can utilise these compounds as sole carbon and energy sources. GC-MS analysis of the culture supernatants from cultures grown in 5-(pentafluorosulfanyl) 2-aminophenol demonstrated the presence of the N-acetylated derivative of the starting substrate and 4-(pentafluorosulfanyl)catechol. Biotransformation experiments with re-suspended cells were also conducted and fluorine-19 NMR analyses of the organic extract and aqueous fraction from suspended cell experiments revealed new resonances of SF 5 -substituted intermediates. Supplementation of suspended cell cultures with yeast extract dramatically improved the degradation of the substrate as well as the release of fluoride ion. 4-(Pentafluorosulfanyl)catechol was shown to be a shunt metabolite and toxic to some of the bacteria. This is the first study to demonstrate that microorganisms can biodegrade SF 5 -substituted aromatic compounds releasing fluoride ion, and biotransform them generating a toxic metabolite.

Resonance energy shifts during nuclear Bragg diffraction of x rays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arthur, J.; Brown, G.S.; Brown, D.E.

1989-10-09

We have observed dramatic changes in the time distribution of synchrotron x rays resonantly scattered from {sup 57}Fe nuclei in a crystal of yttrium iron garnet, which depend on the deviation angle of the incident radiation from the Bragg angle. These changes are caused by small shifts in the effective energies of the hyperfine-split nuclear resonances, an effect of dynamical diffraction for the coherently excited nuclei in the crystal. The very high brightness of the synchro- tron x-ray source allows this effect to be observed in a 15-min measurement.

Green Tunnel Construction Technology and Application

NASA Astrophysics Data System (ADS)

Zhang, J. L.; Shi, P. X.; Huang, J.; Li, H. G.; Zhou, X. Q.

2018-05-01

With the dramatic growth of urban tunnels in recent years, energy saving and environmental protection have received intensive attention in tunnel construction and operation. As reference to the concept of green buildings, this paper proposes the concept of green tunnels. Combining with the key issues of tunnel design, construction, operation and maintenance, the major aspects of green tunnels including prefabricated construction, noise control, ventilation & lighting energy saving, and digital intelligent maintenance are discussed and the future development of green tunnels is outlined with the economic and social benefits as indicators.

The background in a balloon-borne fluorescence-gated proportional counter

NASA Technical Reports Server (NTRS)

Ramsey, B. D.; Bower, C. R.; Dietz, K. L.; Weisskopf, M. C.

1990-01-01

The results of an analysis of the background in a fluorescence-gated proportional counter operating over the energy range 3-150 keV are presented. It is found that the dominant background component is that produced by high energy qamma-rays that penetrate the shields and undergo multiple scattering in the detector body, resulting in photoelectric absorption in the detector gas. A careful choice of materials and thickness can move the peak of this emission outside of the detector sensitive range, thereby dramatically reducing the residual background.

Energy partitioning and impulse dispersion in the decorated, tapered, strongly nonlinear granular alignment: A system with many potential applications

NASA Astrophysics Data System (ADS)

Doney, Robert L.; Agui, Juan H.; Sen, Surajit

2009-09-01

Rapid absorption of impulses using light-weight, small, reusable systems is a challenging problem. An axially aligned set of progressively shrinking elastic spheres, a "tapered chain," has been shown to be a versatile and scalable shock absorber in earlier simulational, theoretical, and experimental works by several authors. We have recently shown (see R. L. Doney and S. Sen, Phys. Rev. Lett. 97, 155502 (2006)) that the shock absorption ability of a tapered chain can be dramatically enhanced by placing small interstitial grains between the regular grains in the tapered chain systems. Here we focus on a detailed study of the problem introduced in the above mentioned letter, present extensive dynamical simulations using parameters for a titanium-aluminum-vanadium alloy Ti6Al4V, derive attendant hard-sphere analyses based formulae to describe energy dispersion, and finally discuss some preliminary experimental results using systems with chrome spheres and small Nitinol interstitial grains to present the underlying nonlinear dynamics of this so-called decorated tapered granular alignment. We are specifically interested in small systems, comprised of several grains. This is because in real applications, mass and volume occupied must inevitably be minimized. Our conclusion is that the decorated tapered chain offers enhanced energy dispersion by locking in much of the input energy in the grains of the tapered chain rather than in the small interstitial grains. Thus, the present study offers insights into how the shock absorption capabilities of these systems can be pushed even further by improving energy absorption capabilities of the larger grains in the tapered chains. We envision that these scalable, decorated tapered chains may be used as shock absorbing components in body armor, armored vehicles, building applications and in perhaps even in applications in rehabilitation science.

Significantly Enhanced Energy Density in Nanocomposite Capacitors Combining the TiO2 Nanorod Array with Poly(vinylidene fluoride).

PubMed

Yao, Lingmin; Pan, Zhongbin; Liu, Shaohui; Zhai, Jiwei; Chen, Haydn H D

2016-10-05

A novel inorganic/polymer nanocomposite, using 1-dimensional TiO 2 nanorod array as fillers (TNA) and poly(vinylidene fluoride) (PVDF) as matrix, has been successfully synthesized for the first time. A carefully designed process sequence includes several steps with the initial epitaxial growth of highly oriented TNA on the fluorine-doped tin oxide (FTO) conductive glass. Subsequently, PVDF is embedded into the nanorods by the spin-coating method followed by annealing and quenching processes. This novel structure with dispersive fillers demonstrates a successful compromise between the electric displacement and breakdown strength, resulting in a dramatic increase in the electric polarization which leads to a significant improvement on the energy density and discharge efficiency. The nanocomposites with various height ratios of fillers between the TNA and total film thickness were investigated by us. The results show that nanocomposite with 18% height ratio fillers obtains maximum increase in the energy density (10.62 J cm -3 ) at a lower applied electric field of 340 MV m -1 , and it also illustrates a higher efficiency (>85%) under the electric field less than 100 MV m -1 . Even when the electric field reached 340 MV m -1 , the efficiency of nanocomposites can still maintained at ∼70%. This energy density exceeds most of the previously reported TiO 2 -based nanocomposite values at such a breakdown strength, which provides another promising design for the next generation of dielectric nanocomposite material, by using the highly oriented nanorod array as fillers for the higher energy density capacitors. Additionally, the finite element simulation has been employed to analyze the distribution of electric fields and electric flux density to explore the inherent mechanism of the higher performance of the TNA/PVDF nanocomposites.

High-order multilayer coated blazed gratings for high resolution soft x-ray spectroscopy

DOE PAGES

Voronov, Dmitriy L.; Goray, Leonid I.; Warwick, Tony; ...

2015-02-17

A grand challenge in soft x-ray spectroscopy is to drive the resolving power of monochromators and spectrometers from the 10 4 achieved routinely today to well above 10 5. This need is driven mainly by the requirements of a new technique that is set to have enormous impact in condensed matter physics, Resonant Inelastic X-ray Scattering (RIXS). Unlike x-ray absorption spectroscopy, RIXS is not limited by an energy resolution dictated by the core-hole lifetime in the excitation process. Using much higher resolving power than used for normal x-ray absorption spectroscopy enables access to the energy scale of soft excitations inmore » matter. These excitations such as magnons and phonons drive the collective phenomena seen in correlated electronic materials such as high temperature superconductors. RIXS opens a new path to study these excitations at a level of detail not formerly possible. However, as the process involves resonant excitation at an energy of around 1 keV, and the energy scale of the excitations one would like to see are at the meV level, to fully utilize the technique requires the development of monochromators and spectrometers with one to two orders of magnitude higher energy resolution than has been conventionally possible. Here we investigate the detailed diffraction characteristics of multilayer blazed gratings. These elements offer potentially revolutionary performance as the dispersive element in ultra-high resolution x-ray spectroscopy. In doing so, we have established a roadmap for the complete optimization of the grating design. Traditionally 1st order gratings are used in the soft x-ray region, but we show that as in the optical domain, one can work in very high spectral orders and thus dramatically improve resolution without significant loss in efficiency.« less

Evidences of quark-gluon plasma formation in central nuclear collisions

NASA Astrophysics Data System (ADS)

Sagun, V. V.; Bugaev, K. A.; Ivanytskyi, A. I.; Oliinychenko, D. R.

2017-01-01

Due to the absence of clear and unambiguous theoretical signals of the deconfinement transition from hadron matter to quark-gluon plasma (QGP) the experimental searches of QGP formation are based the analysis of various irregularities in the collision energy dependence of thermodynamic and hydrodynamic quantities. Here we present several remarkable irregularities at chemical freeze-out (CFO) of hadrons which are found using an advanced version of the hadron resonance gas model (HRGM). Among them are the sharp peaks of the trace anomaly and baryonic density which are seen at the center of mass energies √sNN = 4.9 GeV and √sNN = 9.2 GeV, and the two sets of highly correlated quasi-plateaus in the collision energy dependence of the entropy per baryon, total pion number per baryon, and thermal pion number per baryon which we found at the center of mass energies 3.8-4.9 GeV and 7.6-10 GeV. In addition we found a significant change of slope of the hadron yield ratios {Λ \\over p} and {{Λ - \\bar Λ } \\over {p - \\bar p}}, when the center of mass collision energy increases from 4.3 GeV to 4.9 GeV and from 7.6 GeV to 9.2 GeV [1]. The increase of slopes of these ratios at the collision energy interval 4.3-4.9 GeV is accompanied by a dramatic growth of resonance decays at CFO. We argue that such a strong correlation between the previously found irregularities and an enhancement of strangeness production can serve as the quark-gluon plasma formation signature. Hence, we conclude that a dramatic change of the system properties seen in the narrow collision energy range √sNN = 4.3-4.9 GeV may open entirely new possibilities for experimental studies of QGP properties at NICA JINR and FAIR GSI accelerators.

Joint China-United States Report for Year 1 Insulation Materials and Systems Project Area Clean Energy Research Center Building Energy Efficiency (CERC-BEE)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stovall, Therese K; Biswas, Kaushik; Song, Bo

In November of 2009, the presidents of China and the U.S. announced the establishment of the Clean Energy Research Center (CERC). This broad research effort is co-funded by both countries and involves a large number of research centers and universities in both countries. One part of this program is focused on improving the energy efficiency of buildings. One portion of the CERC-BEE was focused on building insulation systems. The research objective of this effort was to Identify and investigate candidate high performance fire resistant building insulation technologies that meet the goal of building code compliance for exterior wall applications inmore » green buildings in multiple climate zones. A Joint Work Plan was established between researchers at the China Academy of Building Research and Oak Ridge National Laboratory. Efforts in the first year under this plan focused on information gathering. The objective of this research program is to reduce building energy use in China via improved building insulation technology. In cold regions in China, residents often use inefficient heating systems to provide a minimal comfort level within inefficient buildings. In warmer regions, air conditioning has not been commonly used. As living standards rise, energy consumption in these regions will increase dramatically unless significant improvements are made in building energy performance. Previous efforts that defined the current state of the built environment in China and in the U.S. will be used in this research. In countries around the world, building improvements have typically followed the implementation of more stringent building codes. There have been several changes in building codes in both the U.S. and China within the last few years. New U.S. building codes have increased the amount of wall insulation required in new buildings. New government statements from multiple agencies in China have recently changed the requirements for buildings in terms of energy efficiency and fire safety. A related issue is the degree to which new standards are adopted and enforced. In the U.S., standards are developed using a consensus process, and local government agencies are free to implement these standards or to ignore them. For example, some U.S. states are still using 2003 versions of the building efficiency standards. There is also a great variation in the degree to which the locally adopted standards are enforced in different U.S. cities and states. With a more central process in China, these issues are different, but possible impacts of variable enforcement efficacy may also exist. Therefore, current building codes in China will be compared to the current state of building fire-safety and energy-efficiency codes in the U.S. and areas for possible improvements in both countries will be explored. In particular, the focus of the applications in China will be on green buildings. The terminology of 'green buildings' has different meanings to different audiences. The U.S. research is interested in both new, green buildings, and on retrofitting existing inefficient buildings. An initial effort will be made to clarify the scope of the pertinent wall insulation systems for these applications.« less

Optimal Electrical Energy Slewing for Reaction Wheel Spacecraft

NASA Astrophysics Data System (ADS)

Marsh, Harleigh Christian

The results contained in this dissertation contribute to a deeper level of understanding to the energy required to slew a spacecraft using reaction wheels. This work addresses the fundamental manner in which spacecrafts are slewed (eigenaxis maneuvering), and demonstrates that this conventional maneuver can be dramatically improved upon in regards to reduction of energy, dissipative losses, as well as peak power. Energy is a fundamental resource that effects every asset, system, and subsystem upon a spacecraft, from the attitude control system which orients the spacecraft, to the communication subsystem to link with ground stations, to the payloads which collect scientific data. For a reaction wheel spacecraft, the attitude control system is a particularly heavy load on the power and energy resources on a spacecraft. The central focus of this dissertation is reducing the burden which the attitude control system places upon the spacecraft in regards to electrical energy, which is shown in this dissertation to be a challenging problem to computationally solve and analyze. Reducing power and energy demands can have a multitude of benefits, spanning from the initial design phase, to in-flight operations, to potentially extending the mission life of the spacecraft. This goal is approached from a practical standpoint apropos to an industry-flight setting. Metrics to measure electrical energy and power are developed which are in-line with the cost associated to operating reaction wheel based attitude control systems. These metrics are incorporated into multiple families of practical high-dimensional constrained nonlinear optimal control problems to reduce the electrical energy, as well as the instantaneous power burdens imposed by the attitude control system upon the spacecraft. Minimizing electrical energy is shown to be a problem in L1 optimal control which is nonsmooth in regards to state variables as well as the control. To overcome the challenge of nonsmoothness, a method is adopted in this dissertation to transform the nonsmooth minimum electrical energy problem into an equivalent smooth formulation, which then allows standard techniques in optimal control to solve and analyze the problem. Through numerically solving families of optimal control problems, the relationship between electrical energy and transfer time is identified and explored for both off-and on-eigenaxis maneuvering, under minimum dissipative losses as well as under minimum electrical energy. A trade space between on-and off-eigenaxis maneuvering is identified, from which is shown that agile near time optimal maneuvers exist within the energy budget associated with conventional eigenaxis maneuvering. Moreover, even for conventional eigenaxis maneuvering, energy requirements can be dramatically reduced by maneuvering off-eigenaxis. These results address one of the fundamental assumptions in the field of optimal path design verses conventional maneuver design. Two practical flight situations are addressed in this dissertation in regards to reducing energy and power: The case when the attitude of the spacecraft is predetermined, and the case where reaction wheels can not be directly controlled. For the setting where the attitude of spacecraft is on a predefined trajectory, it is demonstrated that reduced energy maneuvers are only attainable though the application of null-motions, which requires control of the reaction wheels. A computationally light formulation is developed minimizing the dissipative losses through the application of null motions. In the situation where the reaction wheels can not be directly controlled, it is demonstrated that energy consumption, dissipative losses, and peak-power loads, of the reaction-wheel array can each be reduced substantially by controlling the input to the attitude control system through attitude steering. It is demonstrated that the open loop trajectories correctly predict the closed loop response when tracked by an attitude control system which does not allow direct command of the reaction wheels.

Geothermal Technology: A Smart Way to Lower Energy Bills

ERIC Educational Resources Information Center

Calahan, Scott

2007-01-01

Heating costs for both natural gas and oil have risen dramatically in recent years--and will likely continue to do so. Consequently, it is important that students learn not only about traditional heating technology, but also about the alternative methods that will surely grow in use in the coming years. One such method is geothermal. In this…

Red Sky with Red Mesa

ScienceCinema

None

2018-01-16

The Red Sky/Red Mesa supercomputing platform dramatically reduces the time required to simulate complex fuel models, from 4-6 months to just 4 weeks, allowing researchers to accelerate the pace at which they can address these complex problems. Its speed also reduces the need for laboratory and field testing, allowing for energy reduction far beyond data center walls.

Energy effects associated with e-commerce: a case-study concerning online sales of personal computers in The Netherlands.

PubMed

Reijnders, L; Hoogeveen, M J

2001-07-01

The introduction of e-commerce is changing purchase and distribution patterns dramatically. One of the observed effects is that logistics become more efficient as products are directly shipped from a manufacturer or wholesaler to an end-user. Another effect is that market transparency increases, which has a downward pressure on prices of many products sold via the Internet. This article addresses the energy implications of e-commerce at the micro level. This is done by quantifying the transport related energy savings in the case of a Dutch online computer reseller and by assessing the extra energy expenditure associated with increased buying power of online buyers. It is found that energy use per article sold by the online computer reseller is lower. However, taking into account indirect effects such as increased consumer buying power, there are scenarios that lead to an overall increase in energy use.

Enhanced Performance of Recycled Aggregate Concrete with Atomic Polymer Technology

DOT National Transportation Integrated Search

2012-06-01

The atomic polymer technology in form of mesoporous inorganic polymer (MIP) can effectively improve material durability and performance of concrete by dramatically increase inter/intragranular bond strength of concrete at nano-scale. The strategy of ...

The Fundamental Re-Thinking and Redesign of the Military Pay Document Processing System.

DTIC Science & Technology

1999-03-01

the Army and Coast Guard’s MPDP can be dramatically improved by eliminating middlemen functions (PAC and finance office) and shortening the value chain using IT along with other transformation enablers.

Liven up Your Student Dramatics with Commedia dell' Arte.

ERIC Educational Resources Information Center

Potter, Jonathan

1980-01-01

Suggests using the ancient Commedia dell' Arte technique of establishing characters and a plot and then allowing the actors to create their own play. Indicates that this improves student performances even in more traditional plays. (TJ)

NREL Discovers Enzyme Domains that Dramatically Improve Performance | News

Science.gov Websites

seven years of thorough experimental work to develop the tools needed to ascertain that there are a . It was the melding of experimental biochemistry and computational science that brought this study to

Recent Advances in Nanotechnology for Diabetes Treatment

PubMed Central

DiSanto, Rocco Michael; Subramanian, Vinayak; Gu, Zhen

2015-01-01

Nanotechnology in diabetes research has facilitated the development of novel glucose measurement and insulin delivery modalities which hold the potential to dramatically improve quality of life for diabetics. Recent progress in the field of diabetes research at its interface with nanotechnology is our focus. In particular, we examine glucose sensors with nanoscale components including metal nanoparticles and carbon nanostructures. The addition of nanoscale components commonly increases glucose sensor sensitivity, temporal response, and can lead to sensors which facilitate continuous in vivo glucose monitoring. Additionally, we survey nanoscale approaches to “closed-loop” insulin delivery strategies which automatically release insulin in response to fluctuating blood glucose levels. “Closing the loop” between blood glucose level (BGL) measurements and insulin administration by removing the requirement of patient action holds the potential to dramatically improve the health and quality of life of diabetics. Advantages and limitations of current strategies, as well as future opportunities and challenges are also discussed. PMID:25641955

Pachymeningeal involvement in POEMS syndrome: dramatic cerebral MRI improvement after lenalidomide therapy.

PubMed

Briani, Chiara; Manara, Renzo; Lessi, Federica; Citton, Valentina; Zambello, Renato; Adami, Fausto

2012-05-01

POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) syndrome is a rare multisystemic disease associated with plasma cell dyscrasia and increased serum or plasma vascular endothelial growth factor (VEGF) levels, the latter likely responsible for several POEMS syndrome manifestations. Whereas peripheral neuropathy is the main neurological feature and a mandatory diagnostic criterium, central nervous system involvement is less common except for papilledema and stroke. We recently reported the frequent occurrence at brain MRI of cranial pachymeningeal involvement ina series of POEMS syndrome patients. Meningeal histopathology revealed hyperplasia of meningothelial cells, neovascularization, and obstructive vessel remodeling without inflammatory signs pointing to a role of VEGF in the meningeal manifestations. Here, we report the dramatic pachymeningeal improvement in patients undergoing lenalidomide therapy. These findings support the therapeutic role of lenalidomide and might shed further light on the pathophysiology of the disease

Cost-effectiveness of robotic-assisted laparoscopic procedures in urologic surgery in the USA.

PubMed

Sleeper, Joshua; Lotan, Yair

2011-01-01

New technologies such as robotic-assisted surgery are constantly introduced clinically without a complete understanding of benefits and costs. This article will discuss general concepts of health economics and apply them to the application of robotic-assisted surgery to urologic procedures. Utilization of robotic surgery has increased dramatically in recent years. This has been most dramatic in the treatment of prostate cancer. The robot adds significant costs from acquisition, maintenance and recurrent instrument costs. These added costs, thus far, have not been associated with significant improvement in outcomes over 'pure' laparoscopy or open procedures. In order for the robot to be cost effective, there needs to be an improvement in efficacy over alternative approaches, and a decrease in costs of the robot or instrumentation. Robotic surgery has not been found to be cost effective in urology. Future studies may yet reveal indirect benefits that are not yet obvious.

Electrical properties of zinc-oxide-based thin-film transistors using strontium-oxide-doped semiconductors

NASA Astrophysics Data System (ADS)

Wu, Shao-Hang; Zhang, Nan; Hu, Yong-Sheng; Chen, Hong; Jiang, Da-Peng; Liu, Xing-Yuan

2015-10-01

Strontium-zinc-oxide (SrZnO) films forming the semiconductor layers of thin-film transistors (TFTs) are deposited by using ion-assisted electron beam evaporation. Using strontium-oxide-doped semiconductors, the off-state current can be dramatically reduced by three orders of magnitude. This dramatic improvement is attributed to the incorporation of strontium, which suppresses carrier generation, thereby improving the TFT. Additionally, the presence of strontium inhibits the formation of zinc oxide (ZnO) with the hexagonal wurtzite phase and permits the formation of an unusual phase of ZnO, thus significantly changing the surface morphology of ZnO and effectively reducing the trap density of the channel. Project supported by the National Natural Science Foundation of China (Grant No. 6140031454) and the Innovation Program of Chinese Academy of Sciences and State Key Laboratory of Luminescence and Applications.

Directed evolution of an ultrastable carbonic anhydrase for highly efficient carbon capture from flue gas

DOE PAGES

Alvizo, Oscar; Nguyen, Luan J.; Savile, Christopher K.; ...

2014-11-03

Carbonic anhydrase (CA) is one of nature’s fastest enzymes and can dramatically improve the economics of carbon capture under demanding environments such as coal-fired power plants. The use of CA to accelerate carbon capture is limited by the enzyme’s sensitivity to the harsh process conditions. Using directed evolution, the properties of a β-class CA from Desulfovibrio vulgaris were dramatically enhanced. Iterative rounds of library design, library generation, and high-throughput screening identified highly stable CA variants that tolerate temperatures of up to 107 °C in the presence of 4.2 M alkaline amine solvent at pH >10.0. This increase in thermostability andmore » alkali tolerance translates to a 4,000,000-fold improvement over the natural enzyme. In conclusion, at pilot scale, the evolved catalyst enhanced the rate of CO2 absorption 25-fold compared with the noncatalyzed reaction.« less

Directed evolution of an ultrastable carbonic anhydrase for highly efficient carbon capture from flue gas

PubMed Central

Alvizo, Oscar; Nguyen, Luan J.; Savile, Christopher K.; Bresson, Jamie A.; Lakhapatri, Satish L.; Solis, Earl O. P.; Fox, Richard J.; Broering, James M.; Benoit, Michael R.; Zimmerman, Sabrina A.; Novick, Scott J.; Liang, Jack; Lalonde, James J.

2014-01-01

Carbonic anhydrase (CA) is one of nature’s fastest enzymes and can dramatically improve the economics of carbon capture under demanding environments such as coal-fired power plants. The use of CA to accelerate carbon capture is limited by the enzyme’s sensitivity to the harsh process conditions. Using directed evolution, the properties of a β-class CA from Desulfovibrio vulgaris were dramatically enhanced. Iterative rounds of library design, library generation, and high-throughput screening identified highly stable CA variants that tolerate temperatures of up to 107 °C in the presence of 4.2 M alkaline amine solvent at pH >10.0. This increase in thermostability and alkali tolerance translates to a 4,000,000-fold improvement over the natural enzyme. At pilot scale, the evolved catalyst enhanced the rate of CO2 absorption 25-fold compared with the noncatalyzed reaction. PMID:25368146

High Energy Astronomy Observatory (HEAO)

NASA Image and Video Library

1980-01-01

The dramatic change in x-ray emission from the Terzan 2 cluster is shown in this series of 2.5-minute exposures taken with the High Energy Astronomy Observatory (HEAO)-2/Einstein Observatory immediately before, during, and after the burst. Total exposure (20 minutes) of the object, including the outburst, is shown in the fourth photograph. These images represent the first observation of an x-ray burst in progress. The actual burst lasted 50 seconds. Among the rarest, and most bizarre, phenomena observed by x-ray astronomers are the so-called cosmic bursters (x-ray sources that suddenly and dramatically increase in intensity then subside). These sudden bursts of intense x-ray radiation apparently come from compact objects with a diameter smaller than 30 miles (48 kilometers). Yet, despite their minuscule size, a typical x-ray burster can release more x-ray energy in a single brief burst than our Sun does in an entire week. The HEAO-2, the first imaging and largest x-ray telescope built to date, was capable of producing actual photographs of x-ray objects. Shortly after launch, the HEAO-2 was nicknamed the Einstein Observatory by its scientific experimenters in honor of the centernial of the birth of Albert Einstein, whose concepts of relativity and gravitation have influenced much of modern astrophysics, particularly x-ray astronomy. The HEAO was designed and developed by TRW, Inc. under the project management of the Marshall Space Flight Center.

Perfect Mirror Design Technology

DTIC Science & Technology

1999-02-01

with Prof. Mario Molina, recipient of the 1995 Nobel Prize in Chemistry. The partnership, along with Aerodyne Research Inc., looked at how sulfur...Corporation is developing standards for nondestructive evaluation ( NDE ) techniques for industry use. Use of the new standards will result in improved...novel testing methodology that dramatically improves the accuracy of NDE techniques used to detect flaws. Basic Research Five years ago, the main

Exploiting trait correlations for next-generation grain yield and end-use quality improvement of U.S. hard winter wheat

USDA-ARS?s Scientific Manuscript database

Since the early 1980s, the land area planted to U.S. hard winter wheat and the share of U.S. wheat in global export markets have both declined dramatically. Improved profitability of other crops relative to wheat, declining or static domestic wheat flour consumption, and an increasingly competitive ...

Intensive hardwood log bucker training using HW Buck dramatically improves value recovery

Treesearch

James B. Pickens; Aaron Everett; Scott Noble; John E. Baumgras; Philip A. Araman; Conrad Waniger; Al Steele

2006-01-01

It has long been recognized that inappropriate placement of crosscuts when manufacturing hardwood logs from harvested stems (log bucking) reduces the value of logs produced. Recent studies have estimated losses in the range from 28% to 38% in the lake states region. It has not, however, been clear how to correct the problem. Efforts to improve value recovery have...

Changing Tires En Route: Michigan Rolls out Millions in School Improvement Grants

ERIC Educational Resources Information Center

Scott, Caitlin

2011-01-01

A recent massive infusion of federal funding marked a dramatic shift in the federal approach to helping low-performing schools. As part of the broad array of economic stimulus efforts included in the American Recovery and Reinvestment Act of 2009 (ARRA), the U.S. Congress appropriated an extra $3 billion for school improvement grants (SIGs) to…

Analysis of health trait data from on-farm computer systems in the U.S. II: Comparison of genomic analyses including two-stage and single-step methods

USDA-ARS?s Scientific Manuscript database

The development of genomic selection methodology, with accompanying substantial gains in reliability for low-heritability traits, may dramatically improve the feasibility of genetic improvement of dairy cow health. Many methods for genomic analysis have now been developed, including the “Bayesian Al...

Emergency department patient satisfaction: customer service training improves patient satisfaction and ratings of physician and nurse skill.

PubMed

Mayer, T A; Cates, R J; Mastorovich, M J; Royalty, D L

1998-01-01

Customer service initiatives in healthcare have become a popular way of attempting to improve patient satisfaction. This study investigates the effect of clinically focused customer service training on patient satisfaction in the setting of a 62,000-visit emergency department and level I trauma center. Analysis of patient complaints, patient compliments, and a statistically verified patient-satisfaction survey indicate that (1) all 14 key quality characteristics identified in the survey increased dramatically in the study period; (2) patient complaints decreased by over 70 percent from 2.6 per 1,000 emergency department (ED) visits to 0.6 per 1,000 ED visits following customer service training; and (3) patient compliments increased more than 100 percent from 1.1 per 1,000 ED visits to 2.3 per 1,000 ED visits. The most dramatic improvement in the patient satisfaction survey came in ratings of skill of the emergency physician, likelihood of returning, skill of the emergency department nurse, and overall satisfaction. These results show that clinically focused customer service training improves patient satisfaction and ratings of physician and nurse skill. They also suggest that such training may offer a substantial competitive market advantage, as well as improve the patients' perception of quality and outcome.

Cold adaptation mechanisms in the ghost moth Hepialus xiaojinensis: Metabolic regulation and thermal compensation.

PubMed

Zhu, Wei; Zhang, Huan; Li, Xuan; Meng, Qian; Shu, Ruihao; Wang, Menglong; Zhou, Guiling; Wang, Hongtuo; Miao, Lin; Zhang, Jihong; Qin, Qilian

2016-02-01

Ghost moths (Lepidoptera: Hepialidae) are cold-adapted stenothermal species inhabiting alpine meadows on the Tibetan Plateau. They have an optimal developmental temperature of 12-16 °C but can maintain feeding and growth at 0 °C. Their survival strategies have received little attention, but these insects are a promising model for environmental adaptation. Here, biochemical adaptations and energy metabolism in response to cold were investigated in larvae of the ghost moth Hepialus xiaojinensis. Metabolic rate and respiratory quotient decreased dramatically with decreasing temperature (15-4 °C), suggesting that the energy metabolism of ghost moths, especially glycometabolism, was sensitive to cold. However, the metabolic rate at 4 °C increased with the duration of cold exposure, indicating thermal compensation to sustain energy budgets under cold conditions. Underlying regulation strategies were studied by analyzing metabolic differences between cold-acclimated (4 °C for 48 h) and control larvae (15 °C). In cold-acclimated larvae, the energy generating pathways of carbohydrates, instead of the overall consumption of carbohydrates, was compensated in the fat body by improving the transcription of related enzymes. The mobilization of lipids was also promoted, with higher diacylglycerol, monoacylglycerol and free fatty acid content in hemolymph. These results indicated that cold acclimation induced a reorganization on metabolic structure to prioritise energy metabolism. Within the aerobic process, flux throughout the tricarboxylic acid (TCA) cycle was encouraged in the fat body, and the activity of α-ketoglutarate dehydrogenase was the likely compensation target. Increased mitochondrial cristae density was observed in the midgut of cold-acclimated larvae. The thermal compensation strategies in this ghost moth span the entire process of energy metabolism, including degration of metabolic substrate, TCA cycle and oxidative phosphorylation, and from an energy budget perspective explains how ghost moths sustain physiological activity in cold environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Terawatt Challenge

NASA Astrophysics Data System (ADS)

Haegel, Nancy

In response to concerns about accelerating climate change, the world is uniting to both envision and enable a global energy system that supports a sustainable environment and broad economic prosperity. Growth in the technology and the deployment of renewable energy has been dramatic. Evidence can be seen in the growth of photovoltaics (PV) and wind as contributors to worldwide electricity production over the last decade. PV and wind provided 1.2% and 3.7% of global electricity production in 2015, compared to 0.1% and 1.3% respectively in 2005. These numbers indicate both the rapid increase in the rate of deployment, as well as the remaining work to be done to extend this trend to transform a massive energy system and provide a significant fraction of the world's future energy demand with renewable energy. Based on recent trends, it is highly likely that global cumulative PV installation will reach terawatt scale in the next few decades. The challenges, as well as the resulting impact, vary greatly depending on whether we envision 1 TW ( 15% of 2015 global electricity capacity), 3 TW ( 50% of 2015 global electricity capacity) or 10 TW, a level that could drive electrification of transportation and industrial sectors and production of solar fuels. This presentation will draw upon the work of the 2016 GA-SERI (Global Alliance of Solar Energy Research Institutes) Terawatt Workshop to assess the feasibility and summarize the challenges for PV as a primary energy source. These challenges include the continuing demand for improved efficiency and reliability, the required magnitude of capital expenditure, the need for a sustainable industry (both financially and environmentally), as well as needs for grid modernization and consistent policies that support global climate goals. Physicists can play important roles in addressing this full range of challenges, from materials science to public policy, as well as in education of the public and its future leaders.

Kondo interactions from band reconstruction in YbInCu 4

DOE PAGES

Jarrige, I.; Kotani, A.; Yamaoka, H.; ...

2015-03-27

We combine resonant inelastic X-ray scattering (RIXS) and model calculations in the Kondo lattice compound YbInCu₄, a system characterized by a dramatic increase in Kondo temperature and associated valence fluctuations below a first-order valence transition at T≃42 K. In this study, the bulk-sensitive, element-specific, and valence-projected charge excitation spectra reveal an unusual quasi-gap in the Yb-derived state density which drives an instability of the electronic structure and renormalizes the low-energy effective Hamiltonian at the transition. Our results provide long-sought experimental evidence for a link between temperature-driven changes in the low-energy Kondo scale and the higher-energy electronic structure of this system.

Biological Implications of Dynamical Phases in Non-equilibrium Networks

NASA Astrophysics Data System (ADS)

Murugan, Arvind; Vaikuntanathan, Suriyanarayanan

2016-03-01

Biology achieves novel functions like error correction, ultra-sensitivity and accurate concentration measurement at the expense of free energy through Maxwell Demon-like mechanisms. The design principles and free energy trade-offs have been studied for a variety of such mechanisms. In this review, we emphasize a perspective based on dynamical phases that can explain commonalities shared by these mechanisms. Dynamical phases are defined by typical trajectories executed by non-equilibrium systems in the space of internal states. We find that coexistence of dynamical phases can have dramatic consequences for function vs free energy cost trade-offs. Dynamical phases can also provide an intuitive picture of the design principles behind such biological Maxwell Demons.

Factors influencing equipment selection in electron beam processing

NASA Astrophysics Data System (ADS)

Barnard, J. W.

2003-08-01

During the eighties and nineties accelerator manufacturers dramatically increased the beam power available for high-energy equipment. This effort was directed primarily at meeting the demands of the sterilization industry. During this era, the perception that bigger (higher power, higher energy) was always better prevailed since the operating and capital costs of accelerators did not increase with power and energy as fast as the throughput. High power was needed to maintain per unit costs low for treatment. This philosophy runs counter to certain present-day realities of the sterilization business as well as conditions influencing accelerator selection in other electron beam applications. Recent experience in machine selection is described and factors affecting choice are presented.

Soft Sun Cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shastry, Tejas

Representing the Argonne-Northwestern Solar Energy Research (ANSER) Center, 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 ANSER is to revolutionize our understanding of molecules, materials and methods necessary tomore » create dramatically more efficient technologies for solar fuels and electricity production.« less

Competition between surface chemisorption and cage formation in Fe12O12 clusters

NASA Astrophysics Data System (ADS)

Gutsev, G. L.; Weatherford, C. A.; Jena, P.; Johnson, E.; Ramachandran, B. R.

2013-01-01

The electronic and geometrical structures of the clusters composed of 12 iron and 12 oxygen atoms are obtained using all-electron density functional theory. It is found that the states with geometrical structures corresponding to oxygen chemisorbed on the ground-state Fe12 cluster surface (Fe12O12) are close in total energy to the states whose geometrical configurations are hollow cages (FeO)12. The lowest total energy state is the ferrimagnetic triplet state of Fe12O12. A ferrimagnetic nonet state of (FeO)12 is only marginally higher in total energy. The clusters are rich in nearly degenerate isomers. Oxygen adsorption dramatically quenches the spin of Fe12 clusters.

Understanding Conversion-Type Electrodes for Lithium Rechargeable Batteries.

PubMed

Yu, Seung-Ho; Feng, Xinran; Zhang, Na; Seok, Jeesoo; Abruña, Héctor D

2018-02-20

The need/desire to lower the consumption of fossil fuels and its environmental consequences has reached unprecedented levels in recent years. A global effort has been undertaken to develop advanced renewable energy generation and especially energy storage technologies, as they would enable a dramatic increase in the effective and efficient use of renewable (and often intermittent) energy sources. The development of electrical energy storage (EES) technologies with high energy and power densities, long life, low cost, and safe use represents a challenge from both the fundamental science and technological application points of view. While the advent and broad deployment of lithium-ion batteries (LIBs) has dramatically changed the EES landscape, their performance metrics need to be greatly enhanced to keep pace with the ever-increasing demands imposed by modern consumer electronics and especially the emerging automotive markets. Current battery technologies are mostly based on the use of a transition metal oxide cathode (e.g., LiCoO 2 , LiFePO 4 , or LiNiMnCoO 2 ) and a graphite anode, both of which depend on intercalation/insertion of lithium ions for operation. While the cathode material currently limits the battery capacity and overall energy density, there is a great deal of interest in the development of high-capacity cathode materials as well as anode materials. Conversion reaction materials have been identified/proposed as potentially high-energy-density alternatives to intercalation-based materials. However, conversion reaction materials react during lithiation to form entirely new products, often with dramatically changed structure and chemistry, by reaction mechanisms that are still not completely understood. This makes it difficult to clearly distinguish the limitations imposed by the mechanism and practical losses from initial particle morphology, synthetic approaches, and electrode preparations. Transition metal compounds such as transition metal oxides, sulfides, fluorides, phosphides, and nitrides can undergo conversion reactions yielding materials with high theoretical capacity (generally from 500 to 1500 mA h g -1 ). In particular, a number of transition metal oxides and sulfides have shown excellent electrochemical properties as high-capacity anode materials. In addition, some transition metal fluorides have shown great potential as cathode materials for Li rechargeable batteries. In this Account we present mechanistic studies, with emphasis on the use of operando methods, of selected examples of conversion-type materials as both potentially high-energy-density anodes and cathodes in EES applications. We also include examples of the conceptually similar conversion-type reactions involving chalcogens and halogens, with emphasis on the Li-S system. In this case we focus on the problems arising from the low electrical conductivities of elemental sulfur and Li 2 S and the "redox shuttle" phenomena of polysulfides. In addition to mechanistic insights from the use of operando methods, we also cover several key strategies in electrode materials design such as controlling the size, morphology, composition, and architecture.

The Successive OH Binding Energies of Sc(OH)n+ for n=1-3

NASA Technical Reports Server (NTRS)

Bauschlicher, Charles W., Jr.; Partridge, Harry; Arnold, James O. (Technical Monitor)

1996-01-01

The geometries of Sc(OH)n+, for n = 1-3, have been optimized using density functional theory, in conjunction with the B3LYP hybrid functional. The zero-point energies are computed at the same level of theory. The successive OH bond energies have been computed at the CCSD(T) level for ScOH+ and Sc(OH)2+. The computed result for ScOD+ is in excellent agreement with the recent experiment of Armentrout and co-workers. There is a dramatic drop for the third OH, because Sc+ has only two valence electrons and therefore the bonding changes when the third OH is added. The difference between the B3LYP and CCSD(T) OH binding energies for the first two OH groups is discussed.

Roles of water molecules in bacteria and viruses

NASA Astrophysics Data System (ADS)

Cox, C. S.

1993-02-01

In addition to water, microbes mainly comprise lipids, carbohydrates, proteins and nucleic acids. Their structure and function singularly and conjointly is affected by water activity. Desiccation leads to dramatic lipid phase changes whereas carbohydrates, proteins and nucleic acids initially suffer spontaneous, reversible low activation energy Maillard reactions forming products that more slowly re-arrange, cross-link etc. to give non-native states. While initial products spontaneously may reverse to native states by raising water activity, later products only do so through energy consumption and enzymatic activity eg. repair. Yet, native states of lipid membranes and associated enzymes are required to generate energy. Consequently, good reserves of high energy compounds (e.g. ATP) and of membrane stabilisers (e.g. trehalose) may be expected to enhance survival following drying and rehydration (e.g. anhydrobiotic organisms).

Effects of probiotic supplementation in different nutrient density diets on growth performance, nutrient digestibility, blood profiles, fecal microflora and noxious gas emission in weaning pig.

PubMed

Lan, Ruixia; Tran, Hoainam; Kim, Inho

2017-03-01

Probiotics can serve as alternatives to antibiotics to increase the performance of weaning pigs, and the intake of probiotics is affected by dietary nutrient density. The objective of this study was to evaluate the effects of a probiotic complex in different nutrient density diets on growth performance, digestibility, blood profiles, fecal microflora and noxious gas emission in weaning pigs. From day 22 to day 42, both high-nutrient-density and probiotic complex supplementation diets increased (P < 0.05) the average daily gain. On day 42, the apparent total tract digestibility (ATTD) of dry matter, nitrogen and gross energy (GE), blood urea nitrogen concentration and NH 3 and H 2 S emissions were increased (P < 0.05) in pigs fed high-nutrient-density diets. Pigs fed probiotic complex supplementation diets had higher (P < 0.05) ATTD of GE than pigs fed non-supplemented diets. Fecal Lactobacillus counts were increased whereas Escherichia coli counts and NH 3 and H 2 S emissions were decreased (P < 0.05) in pigs fed probiotic complex supplementation diets. Interactive effects on average daily feed intake (ADFI) were observed from day 22 to day 42 and overall, where probiotic complex improved ADFI more dramatically in low-nutrient-density diets. The beneficial effects of probiotic complex (Bacillus coagulans, Bacillus licheniformis, Bacillus subtilis and Clostridium butyricum) supplementation on ADFI is more dramatic with low-nutrient-density diets. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Progress towards the 'Golden Age' of biotechnology.

PubMed

Gartland, K M A; Bruschi, F; Dundar, M; Gahan, P B; Viola Magni, M p; Akbarova, Y

2013-07-01

Biotechnology uses substances, materials or extracts derived from living cells, employing 22 million Europeans in a € 1.5 Tn endeavour, being the premier global economic growth opportunity this century. Significant advances have been made in red biotechnology using pharmaceutically and medically relevant applications, green biotechnology developing agricultural and environmental tools and white biotechnology serving industrial scale uses, frequently as process feedstocks. Red biotechnology has delivered dramatic improvements in controlling human disease, from antibiotics to overcome bacterial infections to anti-HIV/AIDS pharmaceuticals such as azidothymidine (AZT), anti-malarial compounds and novel vaccines saving millions of lives. Green biotechnology has dramatically increased food production through Agrobacterium and biolistic genetic modifications for the development of 'Golden Rice', pathogen resistant crops expressing crystal toxin genes, drought resistance and cold tolerance to extend growth range. The burgeoning area of white biotechnology has delivered bio-plastics, low temperature enzyme detergents and a host of feedstock materials for industrial processes such as modified starches, without which our everyday lives would be much more complex. Biotechnological applications can bridge these categories, by modifying energy crops properties, or analysing circulating nucleic acid elements, bringing benefits for all, through increased food production, supporting climate change adaptation and the low carbon economy, or novel diagnostics impacting on personalized medicine and genetic disease. Cross-cutting technologies such as PCR, novel sequencing tools, bioinformatics, transcriptomics and epigenetics are in the vanguard of biotechnological progress leading to an ever-increasing breadth of applications. Biotechnology will deliver solutions to unimagined problems, providing food security, health and well-being to mankind for centuries to come. Copyright © 2013 Elsevier Ltd. All rights reserved.

Assessment of Satellite Capabilities to Detect Impacts of Oil and Natural Gas Activity by Analysis of SONGNEX 2015 Aircraft Measurements

NASA Astrophysics Data System (ADS)

Thayer, M. P.; Keutsch, F. N.; Wolfe, G.; St Clair, J. M.; Hanisco, T. F.; Aikin, K. C.; Brown, S. S.; Dubé, W.; Eilerman, S. J.; Gilman, J.; De Gouw, J. A.; Koss, A.; Lerner, B. M.; Neuman, J. A.; Peischl, J.; Ryerson, T. B.; Thompson, C. R.; Veres, P. R.; Warneke, C.; Washenfelder, R. A.; Wild, R. J.; Womack, C.; Yuan, B.; Zarzana, K. J.

2017-12-01

In the last decade, the rate of domestic energy production from oil and natural gas has grown dramatically, resulting in increased concurrent emissions of methane and other volatile organic compounds (VOCs). Products of VOC oxidation and radical cycling, such as tropospheric ozone (O3) and secondary organic aerosols (SOA), have detrimental impacts on human health and climate. The ability to monitor these emissions and their impact on atmospheric composition from remote-sensing platforms will benefit public health by improving air quality forecasts and identifying localized drivers of tropospheric pollution. New satellite-based instruments, such as TROPOMI (October 2017 launch) and TEMPO (2019-2021 projected launch), will be capable of measuring chemical species related to energy drilling and production on unprecedented spatial and temporal scales, however there is need for improved assessments of their capabilities with respect to specific applications. We use chemical and physical parameters measured via aircraft in the boundary layer and free troposphere during the Shale Oil and Natural Gas Nexus (SONGNEX 2015) field campaign to view chemical enhancements over tight oil and shale gas basins from a satellite perspective. Our in-situ data are used to calculate the planetary boundary layer contributions to the column densities for formaldehyde, glyoxal, O3, and NO2. We assess the spatial resolution and chemical precisions necessary to resolve various chemical features, and compare these limits to TEMPO and TROPOMI capabilities to show the degree to which their retrievals will be able to discern the signatures of oil and natural gas activity.

Real-time subway information for improving transit ridership.

DOT National Transportation Integrated Search

2016-08-01

In recent years, the standardization of transit schedule information has yielded a dramatic increase in the accessibility of computerized transit schedules and given rise to real-time service schedules. Two such real-time service schedules are the Ge...

Direct Formalin Fixation Induces Widespread Genomic Effects in Archival Tissues

EPA Science Inventory

Recent advances in next generation sequencing have dramatically improved transcriptional analysis of degraded RNA from formalin-fixed paraffin-embedded (FFPE) samples. However, little is known about potential genomic artifacts induced by formalin fixation, which could affect toxi...

Zooming in on heat at Baghdad Sulcus

NASA Image and Video Library

2010-02-23

This map shows a dramatically improved view of heat radiation from a warm fissure near the south pole of Saturn icy moon Enceladus. It was obtained by NASA Cassini spacecraft during its Nov. 21, 2009, flyby of that moon.

Polyploidization without mitosis improves in vivo liver transduction with lentiviral vectors.

PubMed

Pichard, Virginie; Couton, Dominique; Desdouets, Chantal; Ferry, Nicolas

2013-02-01

Lentiviral vectors are efficient gene delivery vehicles for therapeutic and research applications. In contrast to oncoretroviral vectors, they are able to infect most nonproliferating cells. In the liver, induction of cell proliferation dramatically improved hepatocyte transduction using all types of retroviral vectors. However, the precise relationship between hepatocyte division and transduction efficiency has not been determined yet. Here we compared gene transfer efficiency in the liver after in vivo injection of recombinant lentiviral or Moloney murine leukemia viral (MoMuLV) vectors in hepatectomized rats treated or not with retrorsine, an alkaloid that blocks hepatocyte division and induces megalocytosis. Partial hepatectomy alone resulted in a similar increase in hepatocyte transduction using either vector. In retrorsine-treated and partially hepatectomized rats, transduction with MoMuLV vectors dropped dramatically. In contrast, we observed that retrorsine treatment combined with partial hepatectomy increased lentiviral transduction to higher levels than hepatectomy alone. Analysis of nuclear ploidy in single cells showed that a high level of transduction was associated with polyploidization. In conclusion, endoreplication could be exploited to improve the efficiency of liver-directed lentiviral gene therapy.

Polyploidization Without Mitosis Improves In Vivo Liver Transduction With Lentiviral Vectors

PubMed Central

Couton, Dominique; Desdouets, Chantal; Ferry, Nicolas

2013-01-01

Abstract Lentiviral vectors are efficient gene delivery vehicles for therapeutic and research applications. In contrast to oncoretroviral vectors, they are able to infect most nonproliferating cells. In the liver, induction of cell proliferation dramatically improved hepatocyte transduction using all types of retroviral vectors. However, the precise relationship between hepatocyte division and transduction efficiency has not been determined yet. Here we compared gene transfer efficiency in the liver after in vivo injection of recombinant lentiviral or Moloney murine leukemia viral (MoMuLV) vectors in hepatectomized rats treated or not with retrorsine, an alkaloid that blocks hepatocyte division and induces megalocytosis. Partial hepatectomy alone resulted in a similar increase in hepatocyte transduction using either vector. In retrorsine-treated and partially hepatectomized rats, transduction with MoMuLV vectors dropped dramatically. In contrast, we observed that retrorsine treatment combined with partial hepatectomy increased lentiviral transduction to higher levels than hepatectomy alone. Analysis of nuclear ploidy in single cells showed that a high level of transduction was associated with polyploidization. In conclusion, endoreplication could be exploited to improve the efficiency of liver-directed lentiviral gene therapy. PMID:23249390

Parameterization of Highly Charged Metal Ions Using the 12-6-4 LJ-Type Nonbonded Model in Explicit Water

PubMed Central

2015-01-01

Highly charged metal ions act as catalytic centers and structural elements in a broad range of chemical complexes. The nonbonded model for metal ions is extensively used in molecular simulations due to its simple form, computational speed, and transferability. We have proposed and parametrized a 12-6-4 LJ (Lennard-Jones)-type nonbonded model for divalent metal ions in previous work, which showed a marked improvement over the 12-6 LJ nonbonded model. In the present study, by treating the experimental hydration free energies and ion–oxygen distances of the first solvation shell as targets for our parametrization, we evaluated 12-6 LJ parameters for 18 M(III) and 6 M(IV) metal ions for three widely used water models (TIP3P, SPC/E, and TIP4PEW). As expected, the interaction energy underestimation of the 12-6 LJ nonbonded model increases dramatically for the highly charged metal ions. We then parametrized the 12-6-4 LJ-type nonbonded model for these metal ions with the three water models. The final parameters reproduced the target values with good accuracy, which is consistent with our previous experience using this potential. Finally, tests were performed on a protein system, and the obtained results validate the transferability of these nonbonded model parameters. PMID:25145273

Heavy Metal-Free Tannin from Bark for Sustainable Energy Storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mukhopadhyay, Alolika; Jiao, Yucong; Katahira, Rui

A novel renewable cathode made from earth abundant, low-cost materials can contribute to the intermittent storage needs of renewable energy-based society. In this work, we report for the first-time tannin from Nature as a cathode material. Our approach exploits the charge storage mechanism of the redox active quinone moiety. Tannins extracted from tree bark using environmental friendly aqueous solvents have the highest phenol content (5.56 mol g -1) among all the natural phenolic biopolymers, 5000 times higher than lignin. Tannins coupled with a conductive polymer polypyrrole acquire high specific capacitance values of 370 F g -1 at 0.5 A gmore » -1 as well as excellent rate performance of 196 F g -1 at 25 A g -1. Additionally, we employed carbonized wood as an electrode substrate to produce a sustainable electrochemical device with dramatically improved performance compared to conventional devices. The high surface area provided by the well-aligned, cellular porosity of wood-derived substrate combined with the high mobility of ions and electrons in the carbonized cell walls and deposited tannin can achieve an areal capacitance of 4.6 F cm -2 at 1 mA cm -2, which is 1.5 times higher than activated wood carbon.« less

The high surface energy of NiO {110} facets incorporated into TiO2 hollow microspheres by etching Ti plate for enhanced photocatalytic and photoelectrochemical activity

NASA Astrophysics Data System (ADS)

Li, Jian; Cui, Hongzhi; Song, Xiaojie; Wei, Na; Tian, Jian

2017-02-01

We present a rational design for the controllable synthesis of NiO/TiO2 hollow microspheres (NTHMs) with Ti plate via a one-pot template-free synthesis strategy. Specifically, to enhance the formation of hollow microspheres, part of the titanium source is provided by the Ti plate. The hollow spherical NiO/TiO2 particles possess unique microstructural characteristics, namely, a higher specific surface area (∼65.82 m2 g-1), a larger mesoporous structure (∼7.79 nm), and hierarchical nanoarchitectures connected with mesopores within the shell (monodispersed size of ∼1 μm and shell thickness of ∼80 nm). In addition, as a cocatalyst for improved catalytic activity, the incorporated NiO nanoparticles with exposed high surface energy {110} facets displayed an outstanding performance. It has been proven that this facile nanostructure possesses remarkably high photoelectrochemical and photocatalytic activities. The main mechanism for enhancement of photocatalytic activity is attributed to the construction of p-n junctions with an inner electric field between TiO2 and NiO, which can dramatically enhance the separation efficiency of the photogenerated electron-hole pairs. This strategy could be applied to fabricate mixed metal oxide hollow microspheres toward the photoelectrochemical catalysis.

Probing the initiation of voltage decay in Li-rich layered cathode materials at the atomic scale

DOE PAGES

Wu, Yan; Ma, Cheng; Yang, Jihui; ...

2015-01-21

Li-rich layered oxides hold great promise for improving the energy density of present-day Li-ion batteries. However, their application is limited by the voltage decay upon cycling, and the origin of such a phenomenon is poorly understood. A major issue is determining the voltage range over which detrimental reactions originate. In the present study, a unique yet effective approach was employed to probe this issue. Instead of studying the materials during the first cycle, electrochemical behavior and evolution of the atomic structures were compared in extensively cycled specimens under varied charge/discharge voltages. With the upper cutoff voltage lowered from 4.8 tomore » 4.4 V, the voltage decay ceased to occur even after 60 cycles. In the meantime, the material maintained its layered structure without any spinel phase emerging at the surface, which is unambiguously shown by the atomic-resolution Z-contrast imaging and electron energy loss spectroscopy. These results have conclusively demonstrated that structural/chemical changes responsible for the voltage decay began between 4.4 and 4.8 V, where the layered-to-spinel transition was the most dramatic structural change observed. Thus, this discovery lays important groundwork for the mechanistic understanding of the voltage decay in Li-rich layered cathode materials.« less

Molecular design of novel fullerene-based acceptors for enhancing the open circuit voltage in polymer solar cells

NASA Astrophysics Data System (ADS)

Tajbakhsh, Mahmood; Kariminasab, Mohaddeseh; Ganji, Masoud Darvish; Alinezhad, Heshmatollah

2017-12-01

Organic solar cells, especially bulk hetero-junction polymer solar cells (PSCs), are the most successful structures for applications in renewable energy. The dramatic improvement in the performance of PSCs has increased demand for new conjugated polymer donors and fullerene derivative acceptors. In the present study, quantum chemical calculations were performed for several representative fullerene derivatives in order to determine their frontier orbital energy levels and electronic structures, thereby helping to enhance their performance in PSC devices. We found correlations between the theoretical lowest unoccupied molecular orbital levels and electrophilicity index of various fullerenes with the experimental open circuit voltage of photovoltaic devices according to the poly(3-hexylthiophene) (P3HT):fullerene blend. The correlations between the structure and descriptors may facilitate screening of the best fullerene acceptor for the P3HT donor. Thus, we considered fullerenes with new functional groups and we predicted the output factors for the corresponding P3HT:fullerene blend devices. The results showed that fullerene derivatives based on thieno-o-quinodimethane-C60 with a methoxy group will have enhanced photovoltaic properties. Our results may facilitate the design of new fullerenes and the development of favorable acceptors for use in photovoltaic applications.

Nanostructured silicon anodes for lithium ion rechargeable batteries.

PubMed

Teki, Ranganath; Datta, Moni K; Krishnan, Rahul; Parker, Thomas C; Lu, Toh-Ming; Kumta, Prashant N; Koratkar, Nikhil

2009-10-01

Rechargeable lithium ion batteries are integral to today's information-rich, mobile society. Currently they are one of the most popular types of battery used in portable electronics because of their high energy density and flexible design. Despite their increasing use at the present time, there is great continued commercial interest in developing new and improved electrode materials for lithium ion batteries that would lead to dramatically higher energy capacity and longer cycle life. Silicon is one of the most promising anode materials because it has the highest known theoretical charge capacity and is the second most abundant element on earth. However, silicon anodes have limited applications because of the huge volume change associated with the insertion and extraction of lithium. This causes cracking and pulverization of the anode, which leads to a loss of electrical contact and eventual fading of capacity. Nanostructured silicon anodes, as compared to the previously tested silicon film anodes, can help overcome the above issues. As arrays of silicon nanowires or nanorods, which help accommodate the volume changes, or as nanoscale compliant layers, which increase the stress resilience of silicon films, nanoengineered silicon anodes show potential to enable a new generation of lithium ion batteries with significantly higher reversible charge capacity and longer cycle life.

Activated Carbon Fiber Paper Based Electrodes with High Electrocatalytic Activity for Vanadium Flow Batteries with Improved Power Density.

PubMed

Liu, Tao; Li, Xianfeng; Xu, Chi; Zhang, Huamin

2017-02-08

Vanadium flow batteries (VFBs) have received high attention for large-scale energy storage due to their advantages of flexibility design, long cycle life, high efficiency, and high safety. However, commercial progress of VFBs has so far been limited by its high cost induced by its low power density. Ultrathin carbon paper is believed to be a very promising electrode for VFB because it illustrates super-low ohmic polarization, however, is limited by its low electrocatalytic activity. In this paper, a kind of carbon paper (CP) with super-high electrocatalytic activity was fabricated via a universal and simple CO 2 activation method. The porosity and oxygen functional groups can be easily tuned via this method. The charge transfer resistance (denoting the electrochemical polarization) of a VFB with CP electrode after CO 2 activation decreased dramatically from 970 to 120 mΩcm 2 . Accordingly, the energy efficiency of a VFB with activated carbon paper as the electrode increased by 13% as compared to one without activation and reaches nearly 80% when the current density is 140 mAcm -2 . This paper provides an effective way to prepare high-performance porous carbon electrodes for VFBs and even for other battery systems.

Heavy Metal-Free Tannin from Bark for Sustainable Energy Storage

DOE PAGES

Mukhopadhyay, Alolika; Jiao, Yucong; Katahira, Rui; ...

2017-11-30

A novel renewable cathode made from earth abundant, low-cost materials can contribute to the intermittent storage needs of renewable energy-based society. In this work, we report for the first-time tannin from Nature as a cathode material. Our approach exploits the charge storage mechanism of the redox active quinone moiety. Tannins extracted from tree bark using environmental friendly aqueous solvents have the highest phenol content (5.56 mol g -1) among all the natural phenolic biopolymers, 5000 times higher than lignin. Tannins coupled with a conductive polymer polypyrrole acquire high specific capacitance values of 370 F g -1 at 0.5 A gmore » -1 as well as excellent rate performance of 196 F g -1 at 25 A g -1. Additionally, we employed carbonized wood as an electrode substrate to produce a sustainable electrochemical device with dramatically improved performance compared to conventional devices. The high surface area provided by the well-aligned, cellular porosity of wood-derived substrate combined with the high mobility of ions and electrons in the carbonized cell walls and deposited tannin can achieve an areal capacitance of 4.6 F cm -2 at 1 mA cm -2, which is 1.5 times higher than activated wood carbon.« less

A soft gamma-ray concentrator using thin-film multilayer structures

NASA Astrophysics Data System (ADS)

Bloser, Peter F.; Aliotta, Paul H.; Echt, Olof; Krzanowski, James E.; Legere, Jason S.; McConnell, Mark L.; Shirazi, Farzane; Tsavalas, John G.; Wong, Emily N.; Kippen, R. Marc

2015-09-01

We have begun to investigate the use of thin-film, multilayer structures to form optics capable of concentrating soft gamma rays with energies greater than 100 keV, beyond the reach of current grazing-incidence hard X-ray mirrors. Alternating layers of low- and high-density materials (e.g., polymers and metals) will channel soft gamma-ray photons via total external reflection. A suitable arrangement of bent structures will then concentrate the incident radiation to a point. Gamma-ray optics made in this way offer the potential for soft gamma-ray telescopes with focal lengths of less than 10 m, removing the need for formation flying spacecraft and opening the field up to balloon-borne instruments. Building on initial investigations at Los Alamos National Laboratory, we are investigating whether it is possible to grow such flexible multi-layer structures with the required thicknesses and smoothness using magnetron sputter and pulsed laser deposition techniques. We present the initial results of tests aimed at fabricating such structures by combining magnetron sputtering with either spin coating or pulsed laser deposition, and demonstrating gamma-ray channeling of 122 keV photons in the laboratory. If successful, this technology offers the potential for transformational increases in sensitivity while dramatically improving the system-level performance of future high-energy astronomy missions through reduced mass and complexity.

A CMOS-based large-area high-resolution imaging system for high-energy x-ray applications

NASA Astrophysics Data System (ADS)

Rodricks, Brian; Fowler, Boyd; Liu, Chiao; Lowes, John; Haeffner, Dean; Lienert, Ulrich; Almer, John

2008-08-01

CCDs have been the primary sensor in imaging systems for x-ray diffraction and imaging applications in recent years. CCDs have met the fundamental requirements of low noise, high-sensitivity, high dynamic range and spatial resolution necessary for these scientific applications. State-of-the-art CMOS image sensor (CIS) technology has experienced dramatic improvements recently and their performance is rivaling or surpassing that of most CCDs. The advancement of CIS technology is at an ever-accelerating pace and is driven by the multi-billion dollar consumer market. There are several advantages of CIS over traditional CCDs and other solid-state imaging devices; they include low power, high-speed operation, system-on-chip integration and lower manufacturing costs. The combination of superior imaging performance and system advantages makes CIS a good candidate for high-sensitivity imaging system development. This paper will describe a 1344 x 1212 CIS imaging system with a 19.5μm pitch optimized for x-ray scattering studies at high-energies. Fundamental metrics of linearity, dynamic range, spatial resolution, conversion gain, sensitivity are estimated. The Detective Quantum Efficiency (DQE) is also estimated. Representative x-ray diffraction images are presented. Diffraction images are compared against a CCD-based imaging system.

Creating Healthy and Just Bioregions

PubMed Central

Pezzoli, Keith; Leiter, Robert A.

2017-01-01

Dramatic changes taking place locally, regionally, globally, demand that we rethink strategies to improve public health, especially in disadvantaged communities where the cumulative impacts of toxicant exposure and other environmental and social stressors are most damaging. The emergent field of sustainability science, including a new bioregionalism for the 21st Century, is giving rise to promising place-based (territorially rooted) approaches. Embedded in this bioregional approach is an Integrated Planning Framework that enables people to map and develop plans and strategies that cut across various scales (e.g., from regional to citywide to neighborhood scale) and various topical areas (e.g., urban land use planning, water resource planning, food systems planning and “green infrastructure” planning) with the specific intent of reducing the impacts of toxicants to public health and the natural environment. This paper describes a case of bioregionally inspired Integrated Planning in San Diego, California (USA). The paper highlights food-water-energy linkages and the importance of “rooted” community-university partnerships and knowledge-action collaboratives in creating healthy and just bioregions. PMID:26812849

Development of Scaffolds for Light Harvesting and Photocatalysis from the Coat Protein of Tobacco Mosaic Virus

NASA Astrophysics Data System (ADS)

Dedeo, Michel Toussaint

The utility of a previously developed TMV-based light harvesting system has been dramatically expanded through the introduction of reactive handles for the site-specific modification of the interior and exterior surfaces. Further experiments to reengineer the coat protein have produced structures with unique, unexpected, and useful assembly properties that complement the newly available surface modifications. Energy transfer from chromophores in the RNA channel of self-assembled TMV structures to the exterior was made possible by conjugation of acceptor dyes and porphyrins to the N-terminus. By repositioning the N-terminus to the pore through circular permutation, this process was repeated to create structures that mimic the light harvesting 1 complex of photosynthetic bacteria. To study and improve upon natural photosynthesis, closely packed chromophore arrays and gold nanoparticles were tethered to the pore of stabilized TMV disks through introduction of a uniquely reactive lysine. Finally, a dimeric TMV coat protein was produced to control the distribution and arrangement of synthetic groups with synergistic activity.

Biocrusts in the context of global change

USGS Publications Warehouse

Reed, Sasha C.; Maestre, Fernando T.; Ochoa-Hueso, Raul; Kuske, Cheryl; Darrouzet-Nardi, Anthony N.; Darby, Brian; Sinsabaugh, Bob; Oliver, Mel; Sancho, Leo; Belnap, Jayne

2016-01-01

A wide range of studies show global environmental change will profoundly affect the structure, function, and dynamics of terrestrial ecosystems. The research synthesized here underscores that biocrust communities are also likely to respond significantly to global change drivers, with a large potential for modification to their abundance, composition, and function. We examine how elevated atmospheric CO2 concentrations, climate change (increased temperature and altered precipitation), and nitrogen deposition affect biocrusts and the ecosystems they inhabit. We integrate experimental and observational data, as well as physiological, community ecology, and biogeochemical perspectives. Taken together, these data highlight the potential for biocrust organisms to respond dramatically to environmental change and show how changes to biocrust community composition translate into effects on ecosystem function (e.g., carbon and nutrient cycling, soil stability, energy balance). Due to the importance of biocrusts in regulating dryland ecosystem processes and the potential for large modifications to biocrust communities, an improved understanding and predictive capacity regarding biocrust responses to environmental change are of scientific and societal relevance.

Nanoparticle induced piezoelectric, super toughened, radiation resistant, multi-functional nanohybrids.

PubMed

Tiwari, Vimal K; Shripathi, T; Lalla, N P; Maiti, Pralay

2012-01-07

We have developed multifunctional nanohybrids of poly(vinylidene fluoride-co-chlorotrifluoroethylene) (CTFE) with a small percentage of surface modified inorganic layered silicate showing dramatic improvement in toughness, radiation resistant and piezoelectric properties vis-à-vis pristine polymer. Massive intercalation (d(001) 1.8 → 3.9 nm) of polymer inside the nanoclay galleries and unique crystallization behavior of the fluoropolymer on the surface of individual silicate layer has been reported. Toughness in the nanohybrid increases more than three orders of magnitude as compared to pure CTFE. High energy radiation (80 MeV Si(+7)) causes chain session, amorphization and creates olefinic bonds in the pure polymer while the nanohybrids are radiation resistant at a similar dose. Nanoclay induces the metastable piezoelectric β-phase in CTFE, suitable for sensor and actuator application. Molecular level changes after irradiation and controlled morphology for smart membrane have been confirmed by using spectroscopy, sol-gel technique, surface morphology studies and in situ residual gas analysis.

Giant increase in piezoelectric coefficient of AlN by Mg-Nb simultaneous addition and multiple chemical states of Nb

NASA Astrophysics Data System (ADS)

Uehara, Masato; Shigemoto, Hokuto; Fujio, Yuki; Nagase, Toshimi; Aida, Yasuhiro; Umeda, Keiichi; Akiyama, Morito

2017-09-01

Aluminum nitride (AlN) is one of piezoelectric materials, which are eagerly anticipated for use in microelectromechanical systems (MEMS) applications such as communication resonators, sensors, and energy harvesters. AlN is particularly excellent in generated voltage characteristics for the MEMS rather than oxide piezoelectric materials such as lead zirconium titanate Pb(Zr, Ti)O3. However, it is necessary to improve the piezoelectric properties of AlN in order to advance the performance of the MEMS. We dramatically increased the piezoelectric coefficient d33 of AlN films by simultaneously adding magnesium (Mg) and niobium (Nb). The d33 of Mg39.3Nb25.0Al35.7N is 22 pC/N, which is about four times that of AlN. The d33 is increased by Mg and Nb simultaneous addition, and is not increased by Mg or Nb single addition. Interestingly, the Nb has multiple chemical states, and which are influenced by the Mg concentration.