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1

NEED Project: Primary Energy Activities  

NSDL National Science Digital Library

This free activity booklet for Grades 2-4 accompanies the NEED Project's Primary Science of Energy curriculum materials. It contains an array of multisensory games, songs, graphics, and seat activities to accompany the energy instructional unit outlined in the NEED Teacher's Guide for Primary Energy. You'll also find printable assessments with answer keys and a student self-evaluation. The NEED energy curriculum is noteworthy because students are first introduced to energy as a physical science concept before being exposed to sources of energy. Using this sequence can help learners differentiate energy forms (thermal, motion, wave, chemical) from energy sources (fossil fuels, wind, geothermal, hydroelectric). See Related Materials for a link to the Teacher's Guide for this unit. The NEED Project is a national initiative to bring innovative curriculum materials in energy education to teachers and learners from the primary grades through college.

2013-04-04

2

SAFE gas turbine cycle primary heat exchangers  

NASA Astrophysics Data System (ADS)

Los Alamos National Laboratory and Marshall Space Flight Center are jointly developing two modular heat pipe heat exchangers, collectively named FIGMENT (Fission Inert Gas Metal Exchanger for Non-nuclear Testing). The FIGMENT heat exchangers are designed to transfer power from the SAFE nuclear reactor cores to gas turbine energy converters. A stainless steel prototype heat exchanger will be built during 2002 in preparation for the construction of a larger refractory metal version. Two promising FIGMENT stainless steel heat exchanger concepts are reviewed here. .

Reid, Robert S.; Kapernick, Richard J.

2002-01-01

3

The Energy Strategy Cycle  

E-print Network

Effective long-range energy planning begins with a reflective analysis that encompasses the complexity of today's energy reality and sets a course for activity to achieve long-range continuing advancement. This strategy approach involves...

Korich, R. D.

1983-01-01

4

Energy Cycle in Living Things  

NSDL National Science Digital Library

This diagram shows how energy from the sun cycles through plants and animals. Plants create sugars through photosynthesis which animals can then use for energy. ATP, glucose, and the mitochondria are also explained. Many key terms are hyperlinked to provide more detailed definitions.

2012-01-01

5

Primary production, nitrogen cycling and the ecosystem role of mangrove microbial mats on Twin Cays, Belize.  

E-print Network

??The seasonal variability of porewater nutrient concentrations, metabolism, nitrogen cycling (denitrification and nitrogen fixation), and primary production (oxygenic and anoxygenic photosynthesis and chemoautotrophy) was examined… (more)

Lee, Rosalynn Y.

2006-01-01

6

NEED Project: Primary Science of Energy Infobook  

NSDL National Science Digital Library

This free infobook provides an overview of energy forms and sources for Grades 2-4, along with hands-on activities, graphics, and classroom presentation materials for teaching an entire unit. Students will first be introduced to energy as a physical science concept before being exposed to sources of energy. Using this sequence can help learners differentiate energy forms (thermal, motion, wave, chemical) from energy sources (fossil fuels, wind, geothermal, hydroelectric). For the companion Student Guide with printable data guides and activities, Primary%20Science%20of%20Energy%20Student%20Guide.pdf" target="_blank">Primary Science of Energy-Student Guide. The NEED Project is a national initiative to bring innovative curriculum materials in energy education to teachers and learners from the primary grades through college.

2013-04-03

7

Free Energy and Internal Combustion Engine Cycles  

E-print Network

The performance of one type (Carnot) of Internal Combustion Engine (ICE) cycle is analyzed within the framework of thermodynamic free energies. ICE performance is different from that of an External Combustion Engine (ECE) which is dictated by Carnot's rule.

Harris, William D

2012-01-01

8

Free Energy and Internal Combustion Engine Cycles  

E-print Network

The performance of one type (Carnot) of Internal Combustion Engine (ICE) cycle is analyzed within the framework of thermodynamic free energies. ICE performance is different from that of an External Combustion Engine (ECE) which is dictated by Carnot's rule.

William D. Harris

2012-01-11

9

SQUIDSIMS is a useful approach to uncover primary signals in the Archean sulfur cycle  

E-print Network

SQUID­SIMS is a useful approach to uncover primary signals in the Archean sulfur cycle Woodward W a combination of scanning high-resolution magnetic supercon- ducting quantum interference device (SQUID million y after deposition. Using magnetic imaging to screen for primary phases, we observed large spatial

Fischer, Woodward

10

Primary vacuum pumps for the fusion reactor fuel cycle  

Microsoft Academic Search

The primary vacuum system for a tokamak-type controlled thermonuclear reactor with 1-GW thermal output is analyzed. The need for recovery, purification, and recycling of deuterium--tritium (D--T) fuel to the reactor leads to the following basic requirements for vacuum pumps at the reactor exhaust: effective pumping speed approx.250 m³ s⁻¹; inlet pressure approx.0.1 Pa; outlet pressure greater than or equal to10

J. L. Hemmerich

1988-01-01

11

The Sun: Earth's Primary Energy Source  

NSDL National Science Digital Library

This article provides elementary school teachers with background knowledge about science concepts needed to understand the first of seven essential principles of climate literacy--the sun is the primary source of energy for our climate system. Graphs, diagrams, and oneline resources provide more background for the teacher. The article appears in a free online magazine that focuses on the seven essential princples of the climate sciences.

Lightle, Kimberly

2011-02-01

12

Influence of local and external processes on the annual nitrogen cycle and primary productivity on Georges Bank: A 3-D  

E-print Network

Influence of local and external processes on the annual nitrogen cycle and primary productivity.V. All rights reserved. Keywords: Nitrogen cycle; Phytoplankton productivity; Modeling; Biological., Influence of local and external processes on the annual nitrogen cycle and primary productivity on Georges

Chen, Changsheng

13

Comparing primary energy attributed to renewable energy with primary energy equivalent to determine carbon abatement in a national context.  

PubMed

The current conventional approach to determining the primary energy associated with non-combustible renewable energy (RE) sources such as wind energy and hydro power is to equate the electricity generated from these sources with the primary energy supply. This paper compares this with an approach that was formerly used by the IEA, in which the primary energy equivalent attributed to renewable energy was equated with the fossil fuel energy it displaces. Difficulties with implementing this approach in a meaningful way for international comparisons lead to most international organisations abandoning the primary energy equivalent methodology. It has recently re-emerged in prominence however, as efforts grow to develop baseline procedures for quantifying the greenhouse gas (GHG) emissions avoided by renewable energy within the context of the Kyoto Protocol credit trading mechanisms. This paper discusses the primary energy equivalent approach and in particular the distinctions between displacing fossil fuel energy in existing plant or in new plant. The approach is then extended provide insight into future primary energy displacement by renewable energy and to quantify the amount of CO2 emissions avoided by renewable energy. The usefulness of this approach in quantifying the benefits of renewable energy is also discussed in an energy policy context, with regard to increasing security of energy supply as well as reducing energy-related GHG (and other) emissions. The approach is applied in a national context and Ireland is case study country selected for this research. The choice of Ireland is interesting in two respects. The first relates to the high proportion of electricity only fossil fuel plants in Ireland resulting in a significant variation between primary energy and primary energy equivalent. The second concerns Ireland's poor performance to date in limiting GHG emissions in line with its Kyoto target and points to the need for techniques to quantify the potential contribution of renewable energy in achieving the target set. PMID:16702067

Gallachóir, Brian P O; O'Leary, Fergal; Bazilian, Morgan; Howley, Martin; McKeogh, Eamon J

2006-01-01

14

NCESR Energy Research Grants Cycle 7 RFP Released: April 11, 2012 1 Energy Research Grants  

E-print Network

, wind energy, geothermal energy and biomass energy; and new or advanced technologies to improve energy NCESR Energy Research Grants Cycle 7 RFP ­ Released: April 11, 2012 1 Energy Research Grants Cycle 7 REQUEST FOR PROPOSAL Issue Date

Farritor, Shane

15

Great Lakes Ice Cycle Primary Investigator: Raymond Assel -NOAA GLERL (Emeritus)  

E-print Network

Great Lakes Ice Cycle Primary Investigator: Raymond Assel - NOAA GLERL (Emeritus) Co Board The formation, duration, and extent of ice cover on the Great Lakes has a major impact balance of the lake, by affecting lake evaporation, heat, and momentum transfers, and on the biology

16

Long-term shifts in life-cycle energy efficiency and carbon intensity.  

PubMed

The quantity of primary energy needed to support global human activity is in large part determined by how efficiently that energy is converted to a useful form. We estimate the system-level life-cycle energy efficiency (EF) and carbon intensity (CI) across primary resources for 2005-2100. Our results underscore that although technological improvements at each energy conversion process will improve technology efficiency and lead to important reductions in primary energy use, market mediated effects and structural shifts toward less efficient pathways and pathways with multiple stages of conversion will dampen these efficiency gains. System-level life-cycle efficiency may decrease as mitigation efforts intensify, since low-efficiency renewable systems with high output have much lower GHG emissions than some high-efficiency fossil fuel systems. Climate policies accelerate both improvements in EF and the adoption of renewable technologies, resulting in considerably lower primary energy demand and GHG emissions. Life-cycle EF and CI of useful energy provide a useful metric for understanding dynamics of implementing climate policies. The approaches developed here reiterate the necessity of a combination of policies that target efficiency and decarbonized energy technologies. We also examine life-cycle exergy efficiency (ExF) and find that nearly all of the qualitative results hold regardless of whether we use ExF or EF. PMID:23409918

Yeh, Sonia; Mishra, Gouri Shankar; Morrison, Geoff; Teter, Jacob; Quiceno, Raul; Gillingham, Kenneth; Riera-Palou, Xavier

2013-03-19

17

MICROPLASTICITY AND ENERGY DISSIPATION IN VERY HIGH CYCLE FATIGUE  

E-print Network

1 of 3 MICROPLASTICITY AND ENERGY DISSIPATION IN VERY HIGH CYCLE FATIGUE Véronique Favier, Ngoc Lam in metals and alloys in Very High Cycle Fatigue (VHCF). In contrast to conventional fatigue tests, detecting ("Microplasticity and energy dissipation in very high cycle fatigue") is an ongoing French project financially

Boyer, Edmond

18

Life cycle assessment of high temperature electrolysis for hydrogen production via nuclear energy  

Microsoft Academic Search

A life cycle assessment (LCA) of one proposed method of hydrogen production—the high temperature electrolysis of water vapor—is presented in this paper. High temperature electrolysis offers an advantage of higher energy efficiency over the conventional low-temperature alkaline electrolysis due to reduced cell potential and consequent electrical energy requirements. The primary energy source for the electrolysis will be advanced nuclear reactors

V. Utgikar; T. Thiesen

2006-01-01

19

EPO modulation of cell-cycle regulatory genes, and cell division, in primary bone marrow erythroblasts  

PubMed Central

Erythropoietin (EPO's) actions on erythroblasts are ascribed largely to survival effects. Certain studies, however, point to EPO-regulated proliferation. To investigate this problem in a primary system, KitposCD71high erythroblasts were prepared from murine bone marrow, and were first used in the array-based discovery of EPO-modulated cell-cycle regulators. Five cell-cycle progression factors were rapidly up-modulated: nuclear protein 1 (Nupr1), G1 to S phase transition 1 (Gspt1), early growth response 1 (Egr1), Ngfi-A binding protein 2 (Nab2), and cyclin D2. In contrast, inhibitory cyclin G2, p27/Cdkn1b, and B-cell leukemia/lymphoma 6 (Bcl6) were sharply down-modulated. For CYCLIN G2, ectopic expression also proved to selectively attenuate EPO-dependent UT7epo cell-cycle progression at S-phase. As analyzed in primary erythroblasts expressing minimal EPO receptor alleles, EPO repression of cyclin G2 and Bcl6, and induction of cyclin D2, were determined to depend on PY343 (and Stat5) signals. Furthermore, erythroblasts expressing a on PY-null EPOR-HM allele were abnormally distributed in G0/G1. During differentiation divisions, EPOR-HM Ter119pos erythroblasts conversely accumulated in S-phase and faltered in an apparent EPO-directed transition to G0/G1. EPO/EPOR signals therefore control the expression of select cell-cycle regulatory genes that are proposed to modulate stage-specific decisions for erythroblast cell-cycle progression. PMID:17548578

Fang, Jing; Menon, Madhu; Kapelle, William; Bogacheva, Olga; Bogachev, Oleg; Houde, Estelle; Browne, Sarah; Sathyanarayana, Pradeep

2007-01-01

20

System measures arc energy dissipated in relay contact cycling  

NASA Technical Reports Server (NTRS)

System, containing cycle timer, measures the energy dissipated at the contacts of a relay operating in an electric circuit. The system measures as well as records the energy for a large number of repetitive operations.

1968-01-01

21

SOLAR THERMAL ORGANIC RANKINE CYCLE AS A RENEWABLE ENERGY OPTION  

Microsoft Academic Search

The objective of the paper is to study the feasibility of an Organic Rankine Cycle (ORC) driven by solar thermal energy as a renewable energy option for small and medium sized commercial usage, power generation of less than 10MW. ORC is principally a conventional Rankine Cycle that uses organic compound as the working fluid instead of water and it is

Cheng Eng Cong; Sanjayan Velautham; Amer Nordin Darus

2005-01-01

22

Nutrient cycling and primary production in the marine systems of the Arctic and Antarctic  

NASA Astrophysics Data System (ADS)

Primary production events in both the Arctic and the Antarctic are highly localized. Carbon-14 incubations that did not account for this caused antarctic primary production estimates to be revised too far downwards from the historic view of high productivity. The primary production regime in the Arctic is even more heterogeneous than in the Antarctic. Arctic primary production rates are in the process of being revised upwards because of a better spatial and temporal distribution of incubation experiments and a re-awakening of interest in estimating new production from the distribution of chemical variables. Similarly, recent examination of temporal changes in nitrate concentrations and recognition of the importance of ice-edge blooms has caused antarctic primary productivity to be revised upwards. In both the Arctic and the Antarctic, the ratio of "new" to total primary production is high, and neglect of this fact can lead to an underestimation of the potential that these regions have for influencing global cycles of bioactive chemicals. Some recent data on temporal changes in nitrate from Fram Strait emphasize the poor state of our knowledge by suggesting an unexpectedly high "new" production rate of ˜1 g C m -2 d -1 for a 35 day experiment that encountered an early Phaeocystis bloom. Chemical distributions suggest that new production over the shelf seas that border the Polar Basin is about 50 g Cm -2 yr -1. The shelves in the Arctic Ocean's marginal and adjacent seas comprise ˜ 25% of the total global continental shelf. These extensive shallow regions have much higher rates of primary production than the Polar Basin and may be globally significant sites of denitrification. Globally significant silica deposition could occur on these shelves or on the adjacent slopes. Because of the differences in geomorphology and stratification, global warming is likely to increase primary production in the Arctic and will probably decrease antarctic primary production. In addition to sharing high ratios of "new" to total primary production, high ammonium concentrations occur in the Arctic and Antarctic. It is possible that these accumulations arise from a strong repression of nitrification at low temperatures.

Codispoti, L. A.; Friederich, G. E.; Sakamoto, C. M.; Gordon, L. I.

1991-08-01

23

Turbulent Mixing of Primary and Secondary Flow Streams in a Rocket-Based Combined Cycle Engine  

NASA Technical Reports Server (NTRS)

This viewgraph presentation gives an overview of the turbulent mixing of primary and secondary flow streams in a rocket-based combined cycle (RBCC) engine. A significant RBCC ejector mode database has been generated, detailing single and twin thruster configurations and global and local measurements. On-going analysis and correlation efforts include Marshall Space Flight Center computational fluid dynamics modeling and turbulent shear layer analysis. Potential follow-on activities include detailed measurements of air flow static pressure and velocity profiles, investigations into other thruster spacing configurations, performing a fundamental shear layer mixing study, and demonstrating single-shot Raman measurements.

Cramer, J. M.; Greene, M. U.; Pal, S.; Santoro, R. J.; Turner, Jim (Technical Monitor)

2002-01-01

24

Open cycle ocean thermal energy conversion system  

DOEpatents

An improved open cycle ocean thermal energy conversion system including a flash evaporator for vaporizing relatively warm ocean surface water and an axial flow, elastic fluid turbine having a vertical shaft and axis of rotation. The warm ocean water is transmitted to the evaporator through a first prestressed concrete skirt-conduit structure circumferentially situated about the axis of rotation. The unflashed warm ocean water exits the evaporator through a second prestressed concrete skirt-conduit structure located circumferentially about and radially within the first skirt-conduit structure. The radially inner surface of the second skirt conduit structure constitutes a cylinder which functions as the turbine's outer casing and obviates the need for a conventional outer housing. The turbine includes a radially enlarged disc element attached to the shaft for supporting at least one axial row of radially directed blades through which the steam is expanded. A prestressed concrete inner casing structure of the turbine has upstream and downstream portions respectively situated upstream and downstream from the disc element. The radially outer surfaces of the inner casing portions and radially outer periphery of the axially interposed disc cooperatively form a downwardly radially inwardly tapered surface. An annular steam flowpath of increasing flow area in the downward axial direction is radially bounded by the inner and outer prestressed concrete casing structures. The inner casing portions each include a transversely situated prestressed concrete circular wall for rotatably supporting the turbine shaft and associated structure. The turbine blades are substantially radially coextensive with the steam flowpath and receive steam from the evaporator through an annular array of prestressed concrete stationary vanes which extend between the inner and outer casings to provide structural support therefor and impart a desired flow direction to the steam.

Wittig, J. Michael (West Goshen, PA)

1980-01-01

25

Morpholino-Mediated Knockdown in Primary Chondrocytes Implicates Hoxc8 in Regulation of Cell Cycle Progression  

PubMed Central

Numerous experiments in mutant and transgenic mice have implicated Hox transcription factors in development of the skeletal system, postulating a role for these proteins in cell proliferation of precursor cells and regulation of cell differentiation. Our own data from Hoxc8 and Hoxd4 transgenic mice suggest that Hoxc8 is involved in cell proliferation during cartilage development. In order to directly assess its role in cell proliferation of a specific skeletal cell type, the cartilage-producing chondrocyte, we performed morpholino-mediated knockdown experiments in normal primary chondrocytes. Through analysis of PCNA expression and staining for phosphorylated Histone 3, two cell cycle markers, we show that interference with Hoxc8 expression in chondrocytes reduces cell proliferation, but in the absence of apoptosis. Instead, cells with a knockdown in Hoxc8 expression appear to be delayed in their progression through the cell cycle. Our results provide evidence for prolonged duration of and delayed exit from M-phase, thus implicating a role for Hoxc8 in controlling cell cycle progression at this critical check point. PMID:19071237

Kamel, Suzan; Kruger, Claudia; Salbaum, J. Michael; Kappen, Claudia

2009-01-01

26

Investigating the usefulness of satellite derived fluorescence data in inferring gross primary productivity within the carbon cycle data assimilation system  

NASA Astrophysics Data System (ADS)

We investigate the utility of satellite measurements of chlorophyll fluorescence (Fs) in constraining gross primary productivity (GPP). We ingest Fs measurements into the Carbon-Cycle Data Assimilation System (CCDAS) which has been augmented by the fluorescence component of the Soil Canopy Observation, Photochemistry and Energy fluxes (SCOPE) model. CCDAS simulates well the patterns of Fs suggesting the combined model is capable of ingesting these measurements. However simulated Fs is insensitive to the key parameter controlling GPP, the carboxylation capacity (Vcmax). Simulated Fs is sensitive to both the incoming absorbed photosynthetically active radiation (aPAR) and leaf chlorophyll concentration both of which are treated as perfectly known in previous CCDAS versions. Proper use of Fs measurements therefore requires enhancement of CCDAS to include and expose these variables.

Koffi, E. N.; Rayner, P. J.; Norton, A. J.; Frankenberg, C.; Scholze, M.

2015-01-01

27

Photosynthesis â Life's Primary Energy Source  

NSDL National Science Digital Library

This lesson covers the process of photosynthesis and the related plant cell functions of transpiration and cellular respiration. Students will learn how engineers can use the natural process of photosynthesis as an exemplary model of a complex â yet efficient â process for converting solar energy to chemical energy or distributing water throughout a system.

Integrated Teaching And Learning Program

28

A novel cryogenic power cycle for LNG cold energy recovery  

Microsoft Academic Search

A novel cryogenic cycle by using a binary mixture as working fluids and combined with a vapor absorption process was proposed to improve the energy recovery efficiency of an LNG (liquefied natural gas) cold power generation. The cycle was simulated with seawater as the heat source and LNG as the heat sink, and the optimization of the power generated per

Yanni Liu; Kaihua Guo

2011-01-01

29

Dynamic life cycle assessment (LCA) of renewable energy technologies  

Microsoft Academic Search

Before new technologies enter the market, their environmental superiority over competing options must be asserted based on a life cycle approach. However, when applying the prevailing status-quo Life Cycle Assessment (LCA) approach to future renewable energy systems, one does not distinguish between impacts which are ‘imported’ into the system due to the ‘background system’ (e.g. due to supply of materials

Martin Pehnt

2006-01-01

30

Energy analysis of electric vehicles using batteries or fuel cells through well-to-wheel driving cycle simulations  

Microsoft Academic Search

This work presents a study of the energy and environmental balances for electric vehicles using batteries or fuel cells, through the methodology of the well to wheel (WTW) analysis, applied to ECE-EUDC driving cycle simulations.Well to wheel balances are carried out considering different scenarios for the primary energy supply. The fuel cell electric vehicles (FCEV) are based on the polymer

Stefano Campanari; Giampaolo Manzolini; Fernando Garcia de la Iglesia

2009-01-01

31

Family Life Cycle and Deforestation in Amazonia: Combining Remotely Sensed Information with Primary Data  

NASA Technical Reports Server (NTRS)

This paper examines the relationships between the socio-demographic characteristics of small settlers in the Brazilian Amazon and the life cycle hypothesis in the process of deforestation. The analysis was conducted combining remote sensing and geographic data with primary data of 153 small settlers along the TransAmazon Highway. Regression analyses and spatial autocorrelation tests were conducted. The results from the empirical model indicate that socio-demographic characteristics of households as well as institutional and market factors, affect the land use decision. Although remotely sensed information is not very popular among Brazilian social scientists, these results confirm that they can be very useful for this kind of study. Furthermore, the research presented by this paper strongly indicates that family and socio-demographic data, as well as market data, may result in misspecification problems. The same applies to models that do not incorporate spatial analysis.

Caldas, M.; Walker, R. T.; Shirota, R.; Perz, S.; Skole, D.

2003-01-01

32

Quantitative Model of Cell Cycle Arrest and Cellular Senescence in Primary Human Fibroblasts  

PubMed Central

Primary human fibroblasts in tissue culture undergo a limited number of cell divisions before entering a non-replicative “senescent” state. At early population doublings (PD), fibroblasts are proliferation-competent displaying exponential growth. During further cell passaging, an increasing number of cells become cell cycle arrested and finally senescent. This transition from proliferating to senescent cells is driven by a number of endogenous and exogenous stress factors. Here, we have developed a new quantitative model for the stepwise transition from proliferating human fibroblasts (P) via reversibly cell cycle arrested (C) to irreversibly arrested senescent cells (S). In this model, the transition from P to C and to S is driven by a stress function ? and a cellular stress response function F which describes the time-delayed cellular response to experimentally induced irradiation stress. The application of this model based on senescence marker quantification at the single-cell level allowed to discriminate between the cellular states P, C, and S and delivers the transition rates between the P, C and S states for different human fibroblast cell types. Model-derived quantification unexpectedly revealed significant differences in the stress response of different fibroblast cell lines. Evaluating marker specificity, we found that SA-?-Gal is a good quantitative marker for cellular senescence in WI-38 and BJ cells, however much less so in MRC-5 cells. Furthermore we found that WI-38 cells are more sensitive to stress than BJ and MRC-5 cells. Thus, the explicit separation of stress induction from the cellular stress response, and the differentiation between three cellular states P, C and S allows for the first time to quantitatively assess the response of primary human fibroblasts towards endogenous and exogenous stress during cellular ageing. PMID:22879912

Schäuble, Sascha; Klement, Karolin; Marthandan, Shiva; Münch, Sandra; Heiland, Ines; Schuster, Stefan; Hemmerich, Peter; Diekmann, Stephan

2012-01-01

33

The Primary and Secondary Production of Germanium: A Life-Cycle Assessment of Different Process Alternatives  

NASA Astrophysics Data System (ADS)

Germanium is a semiconducting metalloid element used in optical fibers, catalysis, infrared optics, solar cells, and light-emitting diodes. The need for Ge in these markets is considered to increase by a steady ~1% on a yearly basis. Its economic importance, coupled with the identified supply risks, has led to the classification of germanium as a critical raw material within Europe. Since the early 1950s, Umicore Electro-Optic Materials has supplied germanium-based materials solutions to its markets around the world. Umicore extracts germanium from a wide range of refining and recycling feeds. The main objectives of this study were to quantify the potential environmental impacts of the production of germanium from production scraps from the photovoltaic industry and to compare them with the potential impacts of the primary production of germanium from coal. The data related to the secondary production are Umicore-specific data. Environmental impact scores have been calculated for the impact categories recommended by the International reference life cycle data system. The comparison of the primary and secondary production highlights the benefit linked to the recycling of metals.

Robertz, Benedicte; Verhelle, Jensen; Schurmans, Maarten

2015-01-01

34

Global constraints on net primary production and inorganic carbon supply during glacial and interglacial cycles  

NASA Astrophysics Data System (ADS)

models have good skill at reproducing glacial-interglacial transitions in climatic variables. Here we propose a simple two-box and two-state relaxation-type model for the upper ocean (surface and permanent thermocline layers) where dissolved inorganic carbon/nutrients are supplied by the deep ocean and through remineralization within the upper ocean. The model is tuned using genetic algorithms to simulate the atmospheric CO2 time series for the last four glacial-interglacial cycles. The fit to the data is very good, with correlations above 0.8, as the upper ocean responds to shifts in (1) the intensity of the meridional overturning circulation, from off to on during the glacial-interglacial transition, and (2) the size and sign of net primary production, with respiration greatly exceeding primary production during interglacial periods and production larger than respiration during the glacial phase. The glacial-interglacial transitions are interpreted as shifts between two distinct metabolic states of the Earth system, with high/low supply of dissolved inorganic carbon and nutrients to the productive upper ocean during interglacial/glacial periods.

Pelegrí, Josep L.; De La Fuente, Patricia; Olivella, Roger; García-Olivares, Antonio

2013-12-01

35

Determining the intensity and energy expenditure during commuter cycling  

PubMed Central

Objectives To determine the intensity and energy expenditure during commuter cycling, and to investigate whether cycling to work at a self?chosen intensity corresponds to recommendations of the Centers for Disease Control and Prevention (CDC) and American College of Sports Medicine (ACSM) for health improvement and ACSM recommendations for fitness improvement. Methods 18 healthy, untrained middle?aged people, who did not cycle to work, underwent two maximal exercise tests (MT and MT2) in order to measure their maximal heart rate and oxygen consumption (VO2). MT2 was performed 24?weeks after MT. Participants were asked to cycle at least three times a week to their workplace over a one?way minimum distance of 2?km. Data on cycling were recorded in a diary. 12?weeks after MT, a field test was conducted, where participants had to cycle to or from their workplace. The same measurements were taken as during MT as markers of exercise intensity. Metabolic equivalents (METs) and energy expenditure were calculated. Results The intensity during the field test was >75% of their maximal aerobic capacity. The mean (SD) MET value was 6.8 (1.9). The energy expenditure during the field test was 220 (115)?kcal or 540 (139)?kcal/h and 1539 (892)?kcal/week. Men consumed significantly (p<0.01) more energy per hour than women. Conclusion Commuter cycling at a self?selected intensity meets the CDC and ACSM recommendations for health improvement and the ACSM recommendations for improvement of cardiorespiratory fitness. However, as the participants cycled faster during the field test than during daily cycling, the results should be interpreted with caution. PMID:17021003

de Geus, B; De Smet, S; Nijs, J; Meeusen, R

2007-01-01

36

Energy Demand in China (Carbon Cycle 2.0)  

SciTech Connect

Lynn Price, LBNL scientist, speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 2, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

Price, Lynn

2010-02-02

37

Inferring Gross Primary Production and Respiration From a Global Carbon Cycle Model Including Carbonyl Sulfide  

NASA Astrophysics Data System (ADS)

Carbonly sulfide (COS), an analog of carbon dioxide is emerging as a useful atmospheric tracer of carbon cycle processes. Previous studies have shown that COS is taken up by leaves in reactions associated with photosynthesis and that the rate of its uptake is closely linked to the rate of gross primary production (GPP). However, unlike CO2, there is apparently no significant source of COS from terrestrial ecosystems. Therefore, changes in the concentration of COS in the atmosphere over these ecosystems reflects the rate of photosynthesis and is largely independent of the rate of respiration (RESP), while that of CO2 reflects the net sum, GPP + RESP = NEE. The potential significance of this can be seen by considering COS and CO2 exchange in a closed box containing either an ecosystem or a leaf from that ecosystem. For a leaf, the ratio of COS/CO2 uptake normalized by the ratio of COS/CO2 concentration (X) is observed to be about 2, while this ratio for an ecosystem (Y) can range from 3 -10. If we know X, and we can measure Y, we may calculate that, GPP = NEE*Y/X and, RESP=NEE*(Y/X-1). Thus, simultaneous measurements of COS and CO2 exchange could provide new information for carbon cycle studies. Toward this end, we have incorporated the biochemical and biophysical mechanisms controlling COS exchange into a land surface model (SIB) and we have used this model to simulate global COS and CO2 fluxes and transported these together with other known sources and sinks in a chemical transport model (PCTM). The model exhibits good skill in simulating observations of the seasonal cycle and vertical profiles of COS and CO2 concentration from NOAA and INTEX-NA over N. America. Though the major features of the observations are captured in the model calculation, discrepancies remain and illustrate some problems in the parameterization of COS fluxes. We use these "modeled data" to test the feasibility of COS-based GPP and RESP estimation.

Berry, J. A.; Montzka, S. A.; Kawa, S. R.; Zhu, Z.; Denning, S.; Campbell, J. E.; Baker, I.

2007-12-01

38

Comparison of global net primary production trends obtained from satellite-based normalized difference vegetation index and carbon cycle model  

Microsoft Academic Search

The global terrestrial net primary production (NPP) trend was estimated from two independent methods, satellite observation data and a carbon cycle model, and the results were compared for validation. The satellite-based NPP trend was estimated from the incoming surface solar radiation data set and a National Oceanic and Atmospheric Administration\\/Advanced Very High Resolution Radiometer data set that was corrected by

Kazuhito Ichii; Yohei Matsui; Yasushi Yamaguchi; Katsuro Ogawa

2001-01-01

39

EFFECT OF ARSENICALS ON THE EXPRESSION OF CELL CYCLE PROTEINS AND EARLY SIGNALING EVENTS IN PRIMARY HUMAN KERATINOCYTES.  

EPA Science Inventory

Effect of Arsenicals on the Expression of Cell Cycle Proteins and Early Signaling Events in Primary Human Keratinocytes. Mudipalli, A, Owen R. D. and R. J. Preston, Environmental Carcinogenesis Division, USEPA, RTP, NC 27711. Environmental exposure to arsenic is a m...

40

The Flow of Energy: Primary Production to Higher Trophic Levels  

NSDL National Science Digital Library

Today we will explore some of the multiple topics related to the flow of energy in ecosystems. Energy is used up and lost as heat as it moves through ecosystems, and new energy is continually added to the earth in the form of solar radiation. As we learned in the last lecture, the earth is an open system in regard to energy.Nutrients and other materials, on the other hand, are continually recirculated within and among ecosystems, and by and large there are no new inputs or losses from the planet. In terms of materials, then, the earth is a closed system. Both energy and materials are essential to ecosystem structure, function, and composition. You have already been exposed to the basic concepts of nutrient cycles; in this lecture we focus on energy. Note that in terms of the cycling of carbon, "materials" and energy can be inter-converted. For example, we know how many calories (a measure of energy) a gram of certain carbon compounds materials such as fats or carbohydrates contain.

Klink, George

41

Zinc-oxygen primary cell yields high energy density  

NASA Technical Reports Server (NTRS)

Zinc-oxygen primary cell yields high energy density for battery used as an auxiliary power source in space vehicle systems. Maximum reliability and minimum battery weight is achieved by using a stacking configuration of 23 series-connected modules with 6 parallel-connected cells per module.

Graff, C. B.

1968-01-01

42

A Satellite View of Global Water and Energy Cycling  

NASA Astrophysics Data System (ADS)

The global water cycle describes liquid, solid and vapor water dynamics as it moves through the atmosphere, oceans and land. Life exists because of water, and civilization depends on adapting to the constraints imposed by water availability. The carbon, water and energy cycles are strongly interdependent - energy is moved through evaporation and condensation, and photosynthesis is closely related to transpiration. There are significant knowledge gaps about water storage, fluxes and dynamics - we currently do not really know how much water is stored in snowpacks, groundwater or reservoirs. The view from space offers a vision for water science advancement. This vision includes observation, understanding, and prediction advancements that will improve water management and to inform water-related infrastructure that planning to provide for human needs and to protect the natural environment. The water cycle science challenge is to deploy a series of coordinated earth observation satellites, and to integrate in situ and space-borne observations to quantify the key water-cycle state variables and fluxes. The accompanying societal challenge is to integrate this information along with water cycle physics, and ecosystems and societal considerations as a basis for enlightened water resource management and to protect life and property from effects of water cycle extremes. Better regional to global scale water-cycle observations and predictions need to be readily available to reduce loss of life and property caused by water-related hazards. To this end, the NASA Energy and Water cycle Study (NEWS) has been documenting the satellite view of the water cycle with a goal of enabling improved, observationally based, predictions of water and energy cycle consequences of Earth system variability and change. NEWS has fostered broad interdisciplinary collaborations to study experimental and operational satellite observations and has developed analysis tools for characterizing air/sea fluxes, ocean circulation, atmospheric states, radiative balances, land surface states, sub-surface hydrology, snow and ice. This presentation will feature an overview of recent progress towards this challenge, and lay out the plan for coordination with complementary international efforts.

Houser, P. R.

2012-12-01

43

Life-cycle energy and greenhouse gas emission benefits of lightweighting in automobiles: review and harmonization.  

PubMed

Replacing conventional materials (steel and iron) with lighter alternatives (e.g., aluminum, magnesium, and composites) decreases energy consumption and greenhouse gas (GHG) emissions during vehicle use but may increase energy consumption and GHG emissions during vehicle production. There have been many life cycle assessment (LCA) studies on the benefits of vehicle lightweighting, but the wide variety of assumptions used makes it difficult to compare results from the studies. To clarify the benefits of vehicle lightweighting we have reviewed the available literature (43 studies). The GHG emissions and primary energy results from 33 studies that passed a screening process were harmonized using a common set of assumptions (lifetime distance traveled, fuel-mass coefficient, secondary weight reduction factor, fuel consumption allocation, recycling rate, and energy intensity of materials). After harmonization, all studies indicate that using aluminum, glass-fiber reinforced plastic, and high strength steel to replace conventional steel decreases the vehicle life cycle energy use and GHG emissions. Given the flexibility in options implied by the variety of materials available and consensus that these materials have substantial energy and emissions benefits, it seems likely that lightweighting will be used increasingly to improve fuel economy and reduce life cycle GHG emissions from vehicles. PMID:23668335

Kim, Hyung Chul; Wallington, Timothy J

2013-06-18

44

Isoprene emissions track the seasonal cycle of canopy temperature, not primary production: evidence from remote sensing  

NASA Astrophysics Data System (ADS)

Isoprene is important in atmospheric chemistry, but its seasonal emission pattern - especially in the tropics, where most isoprene is emitted - is incompletely understood. We set out to discover generalized relationships applicable across many biomes between large-scale isoprene emission and a series of potential predictor variables, including both observed and model-estimated variables related to gross primary production (GPP) and canopy temperature. We used remotely sensed atmospheric concentrations of formaldehyde, an intermediate oxidation product of isoprene, as a proxy for isoprene emission in 22 regions selected to span high to low latitudes, to sample major biomes, and to minimize interference from pyrogenic sources of volatile organic compounds that could interfere with the isoprene signal. Formaldehyde concentrations showed the highest average seasonal correlations with remotely sensed (r = 0.85) and model-estimated (r = 0.80) canopy temperatures. Both variables predicted formaldehyde concentrations better than air temperature (r= 0.56) and a "reference" isoprene model that combines GPP and an exponential function of temperature (r = 0.49), and far better than either remotely sensed green vegetation cover, fPAR (r = 0.25) or model-estimated GPP (r = 0.14). Gross primary production in tropical regions was anti-correlated with formaldehyde concentration (r = -0.30), which peaks during the dry season. Our results were most reliable in the tropics, where formaldehyde observational errors were the least. The tropics are of particular interest because they are the greatest source of isoprene emission as well as the region where previous modelling attempts have been least successful. We conjecture that positive correlations of isoprene emission with GPP and air temperature (as found in temperate forests) may arise simply because both covary with canopy temperature, peaking during the relatively short growing season. The lack of a general correlation between GPP and formaldehyde concentration in the seasonal cycle is consistent with experimental evidence that isoprene emission rates are largely decoupled from photosynthetic rates, and with the likely adaptive significance of isoprene emission in protecting leaves against heat damage and oxidative stress.

Foster, P. N.; Prentice, I. C.; Morfopoulos, C.; Siddall, M.; van Weele, M.

2014-07-01

45

Carbon Cycle 2.0: Nitash Balsara: Energy Storage  

SciTech Connect

Feb. 4, 2010: Humanity emits more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future.

Nitash Balsara

2010-02-16

46

Carbon Cycle 2.0: Nitash Balsara: Energy Storage  

ScienceCinema

Feb. 4, 2010: Humanity emits more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future.

Nitash Balsara

2010-09-01

47

Role of the vapor compression cycle in solar energy utilization  

Microsoft Academic Search

The vapor compression cycle lends itself to solar energy utilization in two important ways. Its ability to utilize a relatively low temperature heat supply to produce space heating via heat pumps allows the use of solar input to the evaporator to provide potential coefficients of performance which are 2 to 3 times higher than present electric driven heat pumps, and

E. A. Kush Jr.; E. A. Jr

1978-01-01

48

Simulation of power cycle with energy utilization diagram  

Microsoft Academic Search

The graphical representation named energy utilization diagram (EUD) is a very useful tool for exergy analysis of chemical processes. This technique can be applied to the power cycle, the combination of heat exchangers and power subsystems. The cooperation of EUD with the process simulator was introduced to retrieve the simulation results and thermodynamic properties. The ASPEN Plus simulator was used

Thongchai Srinophakun; Sangapong Laowithayangkul; Masaru Ishida

2001-01-01

49

Energy spectra and composition of primary cosmic rays  

NASA Astrophysics Data System (ADS)

New results are described on the energy spectra and relative abundances of primary cosmic ray nuclei from carbon to iron. The measurement was performed on the Spacelab-2 mission of the Space Shuttle Challenger in 1985, and extends to energies beyond 1 TeV per amu. The data indicate that the cosmic ray flux arriving near earth becomes enriched with heavier nuclei, most notably iron, as energy increases. Extrapolating to the source, with a simple leaky box model of galactic propagation with rigidity-dependent containment time, relative abundances of the elements are obtained that are quite similar to those reported at lower energy. In particular, the depletion of elements with high first ionization potential relative to the local galactic abundances, seems to persist in the cosmic ray source well up to TeV energies. A single power-law energy spectrum about E exp -2.1 provides a good description of the observed spectra of most elemental species.

Mueller, Dietrich; Swordy, Simon P.; Meyer, Peter; L'Heureux, Jacques; Grunsfeld, John M.

1991-06-01

50

SQUID–SIMS is a useful approach to uncover primary signals in the Archean sulfur cycle  

PubMed Central

Many aspects of Earth’s early sulfur cycle, from the origin of mass-anomalous fractionations to the degree of biological participation, remain poorly understood—in part due to complications from postdepositional diagenetic and metamorphic processes. Using a combination of scanning high-resolution magnetic superconducting quantum interference device (SQUID) microscopy and secondary ion mass spectrometry (SIMS) of sulfur isotopes (32S, 33S, and 34S), we examined drill core samples from slope and basinal environments adjacent to a major Late Archean (?2.6–2.5 Ga) marine carbonate platform from South Africa. Coupled with petrography, these techniques can untangle the complex history of mineralization in samples containing diverse sulfur-bearing phases. We focused on pyrite nodules, precipitated in shallow sediments. These textures record systematic spatial differences in both mass-dependent and mass-anomalous sulfur-isotopic composition over length scales of even a few hundred microns. Petrography and magnetic imaging demonstrate that mass-anomalous fractionations were acquired before burial and compaction, but also show evidence of postdepositional alteration 500 million y after deposition. Using magnetic imaging to screen for primary phases, we observed large spatial gradients in ?33S (>4‰) in nodules, pointing to substantial environmental heterogeneity and dynamic mixing of sulfur pools on geologically rapid timescales. In other nodules, large systematic radial ?34S gradients (>20‰) were observed, from low values near their centers increasing to high values near their rims. These fractionations support hypotheses that microbial sulfate reduction was an important metabolism in organic-rich Archean environments—even in an Archean ocean basin dominated by iron chemistry. PMID:24706767

Fischer, Woodward W.; Fike, David A.; Johnson, Jena E.; Raub, Timothy D.; Guan, Yunbin; Kirschvink, Joseph L.; Eiler, John M.

2014-01-01

51

Life cycle energy requirements and greenhouse gas emissions from large scale energy storage systems  

Microsoft Academic Search

Using life cycle assessment, metrics for calculation of the input energy requirements and greenhouse gas emissions from utility scale energy storage systems have been developed and applied to three storage technologies: pumped hydro storage (PHS), compressed air energy storage (CAES) and advanced battery energy storage (BES) using vanadium and sodium polysulphide electrolytes. In general, the use of energy storage with

Paul Denholm; Gerald L. Kulcinski

2004-01-01

52

Low Cost Solar Energy Conversion (Carbon Cycle 2.0)  

SciTech Connect

Ramamoorthy Ramesh from LBNL's Materials Science Division speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 2, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

Ramesh, Ramamoorthy

2010-02-04

53

Battery energy storage systems life cycle costs case studies  

SciTech Connect

This report presents a comparison of life cycle costs between battery energy storage systems and alternative mature technologies that could serve the same utility-scale applications. Two of the battery energy storage systems presented in this report are located on the supply side, providing spinning reserve and system stability benefits. These systems are compared with the alternative technologies of oil-fired combustion turbines and diesel generators. The other two battery energy storage systems are located on the demand side for use in power quality applications. These are compared with available uninterruptible power supply technologies.

Swaminathan, S.; Miller, N.F.; Sen, R.K. [SENTECH, Inc., Bethesda, MD (United States)

1998-08-01

54

Renewable energy from the sea - organic Rankine Cycle using ocean thermal energy conversion  

Microsoft Academic Search

Rankine cycles using refrigerant- and benzene-series fluids as working fluids in converting low-grade energy from renewable energy resources such as solar energy and ocean thermal energy were investigated in this study. The main purpose is to verify the feasibility of utilizing ocean energy (i.e., ocean thermal energy conversion, OTEC) which can also be combined with solar energy in an organic

S. K. Wang; T. C. Hung

2010-01-01

55

High energy primary electron spectrum observed by the emulsion chamber  

NASA Technical Reports Server (NTRS)

A detector of the emulsion chamber type is used to measure the energy spectrum of cosmic-ray electrons. Two large emulsion chambers, each having an area of 40 by 50 sq cm, are exposed for about 25.5 hr at an average pressure altitude of 3.9 mbar. About 500 high-energy cascades (no less than about 600 GeV) are detected by searching for dark spots on the X-ray films. A power-law energy dependence formula is derived for the spectrum of primary cosmic-ray electrons in the energy region over 100 GeV. The results are in good agreement with the transition curves obtained previously by theoretical and Monte Carlo calculations.

Nishimura, J.; Fujii, M.; Aizu, H.; Hiraiwa, N.; Taira, T.; Kobayashi, T.; Niu, K.; Koss, T. A.; Lord, J. J.; Golden, R. L.

1978-01-01

56

Wood energy fuel cycle optimization in beech and spruce forests  

NASA Astrophysics Data System (ADS)

A novel synergistic approach to reducing emissions from residential wood combustion (RWC) is presented. Wood energy fuel cycle optimization (FCO) aims to provide cleaner burning fuels through optimization of forestry and renewable energy management practices. In this work, beech and spruce forests of average and high quality were modelled and analysed to determine the volume of fuel wood and its associated bark fraction produced during typical forestry cycles. Two separate fuel wood bark production regimes were observed for beech trees, while only one production regime was observed for spruce. The single tree and stand models were combined with existing thinning parameters to replicate existing management practices. Utilizing estimates of initial seedling numbers and existing thinning patterns a dynamic model was formed that responded to changes in thinning practices. By varying the thinning parameters, this model enabled optimization of the forestry practices for the reduction of bark impurities in the fuel wood supply chain. Beech forestry cycles responded well to fuel cycle optimization with volume reductions of bark from fuel wood of between ˜10% and ˜20% for average and high quality forest stands. Spruce, on the other hand, was fairly insensitive to FCO with bark reductions of 0-5%. The responsiveness of beech to FCO further supports its status as the preferred RWC fuel in Switzerland. FCO could easily be extended beyond Switzerland and applied across continental Europe and North America.

Meyer, Nickolas K.; Mina, Marco

2012-03-01

57

Life cycle assessment of primary magnesium production using the Pidgeon process in China  

Microsoft Academic Search

Background, aims, and scope  China has been the largest primary magnesium producer in the world since year 2000 and is an important part of the global\\u000a magnesium supply chain. Almost all of the primary magnesium in China is produced using the Pidgeon process invented in the\\u000a 1940s in Canada. The environmental problems of the primary magnesium production with the Pidgeon process

Feng Gao; Zuoren Nie; Zhihong Wang; Xianzheng Gong; Tieyong Zuo

2009-01-01

58

Energy recovery system using an organic rankine cycle  

DOEpatents

A thermodynamic system for waste heat recovery, using an organic rankine cycle is provided which employs a single organic heat transferring fluid to recover heat energy from two waste heat streams having differing waste heat temperatures. Separate high and low temperature boilers provide high and low pressure vapor streams that are routed into an integrated turbine assembly having dual turbines mounted on a common shaft. Each turbine is appropriately sized for the pressure ratio of each stream.

Ernst, Timothy C

2013-10-01

59

Energy Conversion Advanced Heat Transport Loop and Power Cycle  

SciTech Connect

The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in its early stages of development, research towards coupling a high temperature reactor, electrical generation and hydrogen production is under way. Many aspects of the NGNP must be researched and developed in order to make recommendations on the final design of the plant. Parameters such as working conditions, cycle components, working fluids, and power conversion unit configurations must be understood. Three configurations of the power conversion unit were demonstrated in this study. A three-shaft design with 3 turbines and 4 compressors, a combined cycle with a Brayton top cycle and a Rankine bottoming cycle, and a reheated cycle with 3 stages of reheat were investigated. An intermediate heat transport loop for transporting process heat to a High Temperature Steam Electrolysis (HTSE) hydrogen production plant was used. Helium, CO2, and an 80% nitrogen, 20% helium mixture (by weight) were studied to determine the best working fluid in terms cycle efficiency and development cost. In each of these configurations the relative component size were estimated for the different working fluids. The relative size of the turbomachinery was measured by comparing the power input/output of the component. For heat exchangers the volume was computed and compared. Parametric studies away from the baseline values of the three-shaft and combined cycles were performed to determine the effect of varying conditions in the cycle. This gives some insight into the sensitivity of these cycles to various operating conditions as well as trade offs between efficiency and capital cost. Prametric studies were carried out on reactor outlet temperature, mass flow, pressure, and turbine cooling. Recommendations on the optimal working fluid for each configuration were made. A steady state model comparison was made with a Closed Brayton Cycle (CBC) power conversion system developed at Sandia National Laboratory (SNL). A preliminary model of the CBC was developed in HYSYS for comparison. Temperature and pressure ratio curves for the Capstone turbine and compressor developed at SNL were implemented into the HYSYS model. A comparison between the HYSYS model and SNL loop demonstrated power output predicted by HYSYS was much larger than that in the experiment. This was due to a lack of a model for the electrical alternator which was used to measure the power from the SNL loop. Further comparisons of the HYSYS model and the CBC data are recommended. Engineering analyses were performed for several configurations of the intermediate heat transport loop that transfers heat from the nuclear reactor to the hydrogen production plant. The analyses evaluated parallel and concentric piping arrangements and two different working fluids, including helium and a liquid salt. The thermal-hydraulic analyses determined the size and insulation requirements for the hot and cold leg pipes in the different configurations. Economic analyses were performed to estimate the cost of the va

Oh, C. H.

2006-08-01

60

Rhabdomyosarcoma cells show an energy producing anabolic metabolic phenotype compared with primary myocytes  

PubMed Central

Background The functional status of a cell is expressed in its metabolic activity. We have applied stable isotope tracing methods to determine the differences in metabolic pathways in proliferating Rhabdomysarcoma cells (Rh30) and human primary myocytes in culture. Uniformly 13C-labeled glucose was used as a source molecule to follow the incorporation of 13C into more than 40 marker metabolites using NMR and GC-MS. These include metabolites that report on the activity of glycolysis, Krebs' cycle, pentose phosphate pathway and pyrimidine biosynthesis. Results The Rh30 cells proliferated faster than the myocytes. Major differences in flux through glycolysis were evident from incorporation of label into secreted lactate, which accounts for a substantial fraction of the glucose carbon utilized by the cells. Krebs' cycle activity as determined by 13C isotopomer distributions in glutamate, aspartate, malate and pyrimidine rings was considerably higher in the cancer cells than in the primary myocytes. Large differences were also evident in de novo biosynthesis of riboses in the free nucleotide pools, as well as entry of glucose carbon into the pyrimidine rings in the free nucleotide pool. Specific labeling patterns in these metabolites show the increased importance of anaplerotic reactions in the cancer cells to maintain the high demand for anabolic and energy metabolism compared with the slower growing primary myocytes. Serum-stimulated Rh30 cells showed higher degrees of labeling than serum starved cells, but they retained their characteristic anabolic metabolism profile. The myocytes showed evidence of de novo synthesis of glycogen, which was absent in the Rh30 cells. Conclusion The specific 13C isotopomer patterns showed that the major difference between the transformed and the primary cells is the shift from energy and maintenance metabolism in the myocytes toward increased energy and anabolic metabolism for proliferation in the Rh30 cells. The data further show that the mitochondria remain functional in Krebs' cycle activity and respiratory electron transfer that enables continued accelerated glycolysis. This may be a common adaptive strategy in cancer cells. PMID:18939998

Fan, Teresa WM; Kucia, Magda; Jankowski, Kacper; Higashi, Richard M; Ratajczak, Janina; Ratajczak, Marius Z; Lane, Andrew N

2008-01-01

61

Dosimetric impact evaluation of primary coolant chemistry of the internal tritium breeding cycle of a fusion reactor DEMO  

SciTech Connect

Tritium will be responsible for a large fraction of the environmental impact of the first generation of DT fusion reactors. Today, the efforts of conceptual development of the tritium cycle for DEMO are mainly centred in the so called Inner Breeding Tritium Cycle, conceived as guarantee of reactor fuel self-sufficiency. The EU Fusion Programme develops for the short term of fusion power technology two breeding blanket conceptual designs both helium cooled. One uses Li-ceramic material (HCPB, Helium-Cooled Pebble Bed) and the other a liquid metal eutectic alloy (Pb15.7Li) (HCLL, Helium-Cooled Lithium Lead). Both are Li-6 enriched materials. At a proper scale designs will be tested as Test Blanket Modules in ITER. The tritium cycles linked to both blanket concepts are similar, with some different characteristics. The tritium is recovered from the He purge gas in the case of HCPB, and directly from the breeding alloy through a carrier gas in HCLL. For a 3 GWth self-sufficient fusion reactor the tritium breeding need is few hundred grams of tritium per day. Safety and environmental impact are today the top priority design criteria. Dose impact limits should determine the key margins and parameters in its conception. Today, transfer from the cycle to the environment is conservatively assumed to be operating in a 1-enclosure scheme through the tritium plant power conversion system (intermediate heat exchangers and helium blowers). Tritium loss is caused by HT and T{sub 2} permeation and simultaneous primary coolant leakage through steam generators. Primary coolant chemistry appears to be the most natural way to control tritium permeation from the breeder into primary coolant and from primary coolant through SG by H{sub 2} tritium flux isotopic swamping or steel (EUROFER/INCOLOY) oxidation. A primary coolant chemistry optimization is proposed. Dynamic flow process diagrams of tritium fluxes are developed ad-hoc and coupled with tritiated effluents dose impact evaluations. Dose assessments are obtained from the use of appropriate numeric tools (NORMTRI). (authors)

Velarde, M. [Instituto de Fusion Nuclear (DENIM), ETSII, Universidad Politecnica Madrid UPM, J. Gutierrez Abascal 2, Madrid 28006 (Spain); Sedano, L. A. [Asociacion Euratom-Ciematpara Fusion, Av. Complutense 22, 28040 Madrid (Spain); Perlado, J. M. [Instituto de Fusion Nuclear (DENIM), ETSII, Universidad Politecnica Madrid UPM, J. Gutierrez Abascal 2, Madrid 28006 (Spain)

2008-07-15

62

Energy spectra and composition of primary cosmic rays  

SciTech Connect

New results are described on the energy spectra and relative abundances of primary cosmic ray nuclei from carbon to iron. The measurement was performed on the Spacelab-2 mission of the Space Shuttle Challenger in 1985, and extends to energies beyond 1 TeV per amu. The data indicate that the cosmic ray flux arriving near earth becomes enriched with heavier nuclei, most notably iron, as energy increases. Extrapolating to the source, with a simple leaky box model of galactic propagation with rigidity-dependent containment time, relative abundances of the elements are obtained that are quite similar to those reported at lower energy. In particular, the depletion of elements with high first ionization potential relative to the local galactic abundances, seems to persist in the cosmic ray source well up to TeV energies. A single power-law energy spectrum about E exp {minus}2.1 provides a good description of the observed spectra of most elemental species. 33 refs.

Mueller, D.; Swordy, S.P.; Meyer, P.; L'heureux, J.; Grunsfeld, J.M. (Chicago, University, IL (USA))

1991-06-01

63

Life-Cycle Greenhouse Gas and Energy Analyses of Algae Biofuels Production  

E-print Network

Life-Cycle Greenhouse Gas and Energy Analyses of Algae Biofuels Production Transportation Energy algae life cycle studies and compare new analyses of multiple production scenarios and process the life cycle greenhouse gas emissions, net energy consumption, and net liquid fuels production

64

Analysis and optimization of a cascading power cycle with liquefied natural gas (LNG) cold energy recovery  

Microsoft Academic Search

The effective utilization of the cryogenic energy associated with LNG vaporization is quite important. In this paper a cascading power cycle with LNG directly expanding consisting of a Rankine cycle with ammonia–water as working fluid and a power cycle of combustion gas is proposed to recover cryogenic energy of LNG. Energy equilibrium equations and exergy equilibrium equations of each equipment

T. Lu

2009-01-01

65

The seasonal cycle of phytoplankton biomass and primary productivity in the Ross Sea, Antarctica  

Microsoft Academic Search

Phytoplankton standing stocks and carbon assimilation were measured during four cruises to the southern Ross Sea, Antarctica during 1996 and 1997 in order to assess the details of the seasonal cycle of biomass and productivity. The seasonal composite showed that phytoplankton biomass increased rapidly during the austral spring, and integrated chlorophyll reached a maximum during the summer (January 15) and

Walker O. Smith Jr; John Marra; Michael R. Hiscock; Richard T. Barber

2000-01-01

66

The NASA Energy and Water Cycle Extreme (NEWSE) Integration Project  

NASA Technical Reports Server (NTRS)

Skillful predictions of water and energy cycle extremes (flood and drought) are elusive. To better understand the mechanisms responsible for water and energy extremes, and to make decisive progress in predicting these extremes, the collaborative NASA Energy and Water cycle Extremes (NEWSE) Integration Project, is studying these extremes in the U.S. Southern Great Plains (SGP) during 2006-2007, including their relationships with continental and global scale processes, and assessment of their predictability on multiple space and time scales. It is our hypothesis that an integrative analysis of observed extremes which reflects the current understanding of the role of SST and soil moisture variability influences on atmospheric heating and forcing of planetary waves, incorporating recently available global and regional hydro- meteorological datasets (i.e., precipitation, water vapor, clouds, etc.) in conjunction with advances in data assimilation, can lead to new insights into the factors that lead to persistent drought and flooding. We will show initial results of this project, whose goals are to provide an improved definition, attribution and prediction on sub-seasonal to interannual time scales, improved understanding of the mechanisms of decadal drought and its predictability, including the impacts of SST variability and deep soil moisture variability, and improved monitoring/attributions, with transition to applications; a bridging of the gap between hydrological forecasts and stakeholders (utilization of probabilistic forecasts, education, forecast interpretation for different sectors, assessment of uncertainties for different sectors, etc.).

House, P. R.; Lapenta, W.; Schiffer, R.

2008-01-01

67

Recovered Energy Generation Using an Organic Rankine Cycle System  

SciTech Connect

This paper describes the results of a project demonstrating the technical and economic feasibility of capturing thermal energy from a 35,000 hp (27 MW) gas turbine driving a natural gas pipeline compressor with a Recovered Energy Generation (REG) system to produce 5.5 MW of electricity with no additional fuel and near-zero emissions. The REG is based on a modified Organic Rankine Cycle (ORC). Other major system elements include a waste-heat-to-oil heat exchanger with bypass, oil-to-pentane heat exchanger with preheater, recuperator, condenser, pentane turbine, generator and synchronizing breaker and all power and control systems required for the automatic operation of the REG. When operating at design heat input available from the gas turbine exhaust, the REG system consistently delivered 5.5 MW or more output to the grid at up to 15 percent heat conversion efficiency. The REG system improved the overall energy efficiency by 28%, from 32% simple cycle efficiency to 41% for the combined system. Significant lessons learned from this project are discussed as well as measured performance and economic considerations.

Leslie, Neil [Gas Technology Institute] [Gas Technology Institute; Sweetser, Richard [Exergy Partners Corp.] [Exergy Partners Corp.; Zimron, Ohad [Ormat] [Ormat; Stovall, Therese K [ORNL] [ORNL

2009-01-01

68

Life cycle cost and energy analysis of a Net Zero Energy House with solar combisystem  

Microsoft Academic Search

The Net Zero Energy House (NZEH) presented in this paper is an energy efficient house that uses available solar technologies to generate at least as much primary energy as the house uses over the course of the year. The computer simulation results show that it is technically feasible to reach the goal of NZEH in the cold climate of Montreal.

Mitchell Leckner; Radu Zmeureanu

2011-01-01

69

A novel thermomechanical energy conversion cycle Ian M. McKinley, Felix Y. Lee, Laurent Pilon  

E-print Network

]. Other methods for direct mechanical to electrical energy conversion include electromagnet, electrostatic to convert ther- mal energy directly into electricity. Note that none of these energy conversion methods: Pyroelectric materials Direct energy conversion Waste heat harvesting Ferroelectric materials Olsen cycle

Pilon, Laurent

70

Wogonin induces cell cycle arrest and erythroid differentiation in imatinib-resistant K562 cells and primary CML cells.  

PubMed

Wogonin, a flavonoid derived from Scutellaria baicalensis Georgi, has been demonstrated to be highly effective in treating hematologic malignancies. In this study, we investigated the anticancer effects of wogonin on K562 cells, K562 imatinib-resistant cells, and primary patient-derived CML cells. Wogonin up-regulated transcription factor GATA-1 and enhanced binding between GATA-1 and FOG-1, thereby increasing expression of erythroid-differentiation genes. Wogonin also up-regulated the expression of p21 and induced cell cycle arrest. Studies employing benzidine staining and analyses of cell surface markers glycophorin A (GPA) and CD71 indicated that wogonin promoted differentiation of K562, imatinib-resistant K562, and primary patient-derived CML cells. Wogonin also enhanced binding between GATA-1 and MEK, resulting in inhibition of the growth of CML cells. Additionally, in vivo studies showed that wogonin decreased the number of CML cells and prolonged survival of NOD/SCID mice injected with K562 and imatinib-resistant K562 cells. These data suggested that wogonin induces cycle arrest and erythroid differentiation in vitro and inhibits proliferation in vivo. PMID:25149543

Yang, Hao; Hui, Hui; Wang, Qian; Li, Hui; Zhao, Kai; Zhou, Yuxin; Zhu, Yu; Wang, Xiaotang; You, Qidong; Guo, Qinglong; Lu, Na

2014-09-30

71

Wogonin induces cell cycle arrest and erythroid differentiation in imatinib-resistant K562 cells and primary CML cells  

PubMed Central

Wogonin, a flavonoid derived from Scutellaria baicalensis Georgi, has been demonstrated to be highly effective in treating hematologic malignancies. In this study, we investigated the anticancer effects of wogonin on K562 cells, K562 imatinib-resistant cells, and primary patient-derived CML cells. Wogonin up-regulated transcription factor GATA-1 and enhanced binding between GATA-1 and FOG-1, thereby increasing expression of erythroid-differentiation genes. Wogonin also up-regulated the expression of p21 and induced cell cycle arrest. Studies employing benzidine staining and analyses of cell surface markers glycophorin A (GPA) and CD71 indicated that wogonin promoted differentiation of K562, imatinib-resistant K562, and primary patient-derived CML cells. Wogonin also enhanced binding between GATA-1 and MEK, resulting in inhibition of the growth of CML cells. Additionally, in vivo studies showed that wogonin decreased the number of CML cells and prolonged survival of NOD/SCID mice injected with K562 and imatinib-resistant K562 cells. These data suggested that wogonin induces cycle arrest and erythroid differentiation in vitro and inhibits proliferation in vivo. PMID:25149543

Wang, Qian; Li, Hui; Zhao, Kai; Zhou, Yuxin; Zhu, Yu; Wang, Xiaotang; You, Qidong; Guo, Qinglong; Lu, Na

2014-01-01

72

An advanced zero emission power cycle with integrated low temperature thermal energy  

Microsoft Academic Search

An innovative zero emission hybrid cycle named HICES (hybrid and improved CES cycle) is presented in this paper. It can utilize fossil fuel and low quality thermal energy such as waste heat from industrial processes and solar thermal energy for highly efficient electric power generation. In the HICES cycle, natural gas is internally combusted with pure oxygen. External low quality

Chenhua Gou; Ruixian Cai; Guoqiang Zhang

2006-01-01

73

Decision-making of nuclear energy policy: application of environmental management tool to nuclear fuel cycle  

Microsoft Academic Search

This study aims to evaluate and estimate the environmental impacts of nuclear fuel cycles and to support the decision-making of nuclear energy policy, relating to a selection of environmentally preferred nuclear fuel cycle for the environmentally sound and sustainable development of nuclear energy. To achieve this objective, life cycle assessment (LCA) as an environmental management tool is applied to the

Young Eal Lee; Kyoo-Kun Koh

2002-01-01

74

Altered cytokine gene expression in peripheral blood monocytes across the menstrual cycle in primary dysmenorrhea: a case-control study.  

PubMed

Primary dysmenorrhea is one of the most common gynecological complaints in young women, but potential peripheral immunologic features underlying this condition remain undefined. In this paper, we compared 84 common cytokine gene expression profiles of peripheral blood mononuclear cells (PBMCs) from six primary dysmenorrheic young women and three unaffected controls on the seventh day before (secretory phase), and the first (menstrual phase) and the fifth (regenerative phase) days of menstruation, using a real-time PCR array assay combined with pattern recognition and gene function annotation methods. Comparisons between dysmenorrhea and normal control groups identified 11 (nine increased and two decreased), 14 (five increased and nine decreased), and 15 (seven increased and eight decreased) genes with ? 2-fold difference in expression (P<0.05) in the three phases of menstruation, respectively. In the menstrual phase, genes encoding pro-inflammatory cytokines (IL1B, TNF, IL6, and IL8) were up-regulated, and genes encoding TGF-? superfamily members (BMP4, BMP6, GDF5, GDF11, LEFTY2, NODAL, and MSTN) were down-regulated. Functional annotation revealed an excessive inflammatory response and insufficient TGF-? superfamily member signals with anti-inflammatory consequences, which may directly contribute to menstrual pain. In the secretory and regenerative phases, increased expression of pro-inflammatory cytokines and decreased expression of growth factors were also observed. These factors may be involved in the regulation of decidualization, endometrium breakdown and repair, and indirectly exacerbate primary dysmenorrhea. This first study of cytokine gene expression profiles in PBMCs from young primary dysmenorrheic women demonstrates a shift in the balance between expression patterns of pro-inflammatory cytokines and TGF-? superfamily members across the whole menstrual cycle, underlying the peripheral immunologic features of primary dysmenorrhea. PMID:23390521

Ma, Hongyue; Hong, Min; Duan, Jinao; Liu, Pei; Fan, Xinsheng; Shang, Erxin; Su, Shulan; Guo, Jianming; Qian, Dawei; Tang, Yuping

2013-01-01

75

ENERGY SPECTRUM OF PRIMARY COSMIC RAYS ABOVE 1017 OBTAINED USING AKENO 20 KM2  

E-print Network

OG 6.3-3 ENERGY SPECTRUM OF PRIMARY COSMIC RAYS ABOVE 1017 EV OBTAINED USING AKENO 20 KM2 ARRAY M, Tokyo Institute of Technology, Tokyo 152, Japan . Institute of High Energy Physics, Academia Sinica these showers, 60 of them are initiated by primaries with energies larger than 1019 eV. The energy spectrum

76

The Annual Cycle of the Energy Budget. Part II: Meridional Structures and Poleward Transports  

E-print Network

) and Clouds and Earth's Radiant Energy System (CERES) are used along with estimates of energy storageThe Annual Cycle of the Energy Budget. Part II: Meridional Structures and Poleward Transports JOHN of energy in the atmosphere, ocean, and land are evaluated holisti- cally for the mean and annual cycle

Fasullo, John

77

Toward Describing the Effects of Ozone Depletion on Marine Primary Productivity and Carbon Cycling  

NASA Technical Reports Server (NTRS)

This project was aimed at improved predictions of the effects of UVB and ozone depletion on marine primary productivity and carbon flux. A principal objective was to incorporate a new analytical description of photosynthesis as a function of UV and photosynthetically available radiation (Cullen et. al., Science 258:646) into a general oceanographic model. We made significant progress: new insights into the kinetics of photoinhibition were used in the analysis of experiments on Antarctic phytoplankton to generate a general model of UV-induced photoinhibition under the influence of ozone depletion and vertical mixing. The way has been paved for general models on a global scale.

Cullen, John J.

1995-01-01

78

A simple global carbon and energy coupled cycle model for global warming simulation: sensitivity to the light saturation effect  

NASA Astrophysics Data System (ADS)

A simple Earth system model, the Four-Spheres Cycle of Energy and Mass (4-SCEM) model, has been developed to simulate global warming due to anthropogenic CO2 emission. The model consists of the Atmosphere-Earth Heat Cycle (AEHC) model, the Four Spheres Carbon Cycle (4-SCC) model, and their feedback processes. The AEHC model is a one-dimensional radiative convective model, which includes the greenhouse effect of CO2 and H2O, and one cloud layer. The 4-SCC model is a box-type carbon cycle model, which includes biospheric CO2 fertilization, vegetation area variation, the vegetation light saturation effect and the HILDA oceanic carbon cycle model. The feedback processes between carbon cycle and climate considered in the model are temperature dependencies of water vapor content, soil decomposition and ocean surface chemistry. The future status of the global carbon cycle and climate was simulated up to the year 2100 based on the "business as usual" (IS92a) emission scenario, followed by a linear decline in emissions to zero in the year 2200. The atmospheric CO2 concentration reaches 645 ppmv in 2100 and a peak of 760 ppmv approximately in the year 2170, and becomes a steady state with 600 ppmv. The projected CO2 concentration was lower than those of the past carbon cycle studies, because we included the light saturation effect of vegetation. The sensitivity analysis showed that uncertainties derived from the light saturation effect of vegetation and land use CO2 emissions were the primary cause of uncertainties in projecting future CO2 concentrations. The climate feedback effects showed rather small sensitivities compared with the impacts of those two effects. Satellite-based net primary production trends analyses can somewhat decrease the uncertainty in quantifying CO2 emissions due to land use changes. On the other hand, as the estimated parameter in vegetation light saturation was poorly constrained, we have to quantify and constrain the effect more accurately.

Ichii, Kazuhito; Matsui, Yohei; Murakami, Kazutaka; Mukai, Toshikazu; Yamaguchi, Yasushi; Ogawa, Katsuro

2003-04-01

79

Optimal Life Cycle Cost Design for an Energy Efficient Manufacturing Facility  

E-print Network

OPTIMAL LIFE CYCLE COST DESIGN FOR AN ENERGY EFFICIENT MANUFACTURING FACIL ITY Charles T. Thompson William P. Beach Regional Manager, Corporate Energy Management Project Engineer . Corporate Energy Management Texas Instruments Incorporated Texas...

Thompson, C. T.; Beach, W. P.

1985-01-01

80

Energy efficient iron based electronic field cycling magnet  

NASA Astrophysics Data System (ADS)

A new concept for an energy efficient electromagnet for fast field cycling NMR applications as well as its construction and first test results are presented. The magnet, which provides a rectangular sample space of 17 × 25 mm, has an iron yoke and pole pieces optimised with respect to the B0 homogeneity. The maximum field is 0.66 T at a current of 320 A; its field inhomogeneity for a cylindrical sample (length 7 mm, diameter 6 mm) is about 50 ppm. The power dissipation during polarisation at 0.55 T is as low as 1.4 kW. The magnet is powered by a commercially available power supply and can be rapidly switched with a slew rate of 0.55 T/ms. The system has shown a stability of 50 ppm/h.

Plendl, Dirk; Fujara, Marian; Privalov, Alexei F.; Fujara, Franz

2009-06-01

81

Energy harvesting measurements from stall flutter limit cycle oscillations  

NASA Astrophysics Data System (ADS)

Results from experiments using a two-degree-of-freedom airfoil system are presented. Air speeds of the airfoil are determined at which dynamic flutter can be initiated and where limit cycle oscillations (LCO) can be excited by initial (pitch or plunge) displacements. LCO's with large pitch angle displacements attributed to stall flutter behavior are measured. The LCO oscillations are converted into electric power by an electromagnetic-inductor device. The energy harvester consists of three magnets in which one magnet floats between two fixed magnets. The force-displacement relationship of the harvester is best described by a fifth-order polynomial. The integration of the harvester into the airfoil system introduces nonlinear stiffness into the vertical (plunge) direction. When the LCO has been initiated, displacement amplitudes and resulting power generation are measured.

Chen, Jasper; Dhanushkodi, Adit; Lee, Christopher L.

2014-04-01

82

Osteogenic potential of punica granatum through matrix mineralization, cell cycle progression and runx2 gene expression in primary rat osteoblasts.  

PubMed

BackgroundOsteoporosis is one of the prevalent diseases in ageing populations. Due to side effects of many chemotherapeutic agents, there is always a need to search for herbal products to treat the disorder. Punica granatum (PG) represent a potent fruit-bearing medicinal herb which exerted valuable anti-osteoporotic activities. The present study was carried out to validate the in vitro osteogenic effects of the PG seed extract in primary calvarial osteoblast cultures harvested from neonatal rats.MethodsThe ethanolic extract of PG was subjected to evaluate cell proliferation, regeneration, mineralization and formation of collagen matrix using MTT, alkaline phosphatase, Alizarin Red-S staining and Sirius Red dye, respectively. Cell cycle progression and osteogenic gene Runx2 expression were carried out by flow cytometry and real time PCR, respectively.ResultsExposure of different concentrations (10¿100 ¿g/ml) of the extract on osteoblastic cells showed characteristic morphological changes and increment in cell number. A significant growth in cell proliferation, ALP activity, collagen contents and matrix mineralization of osteoblasts in a dose dependent manner (p¿<¿0.05), suggested that PG has a stimulatory effect on osteoblastic bone formation or potential activity against osteoporosis. In addition, PG extract also enhanced DNA content in S phase of cell cycle and Runx2 gene expression level in osteoblasts.ConclusionThe data clearly indicated that PG promoting bone cell proliferation and differentiation in primary osteoblasts might be due to elevating the osteogenic gene Runx2 expression. The present study provides an evidence for PG could be a promising herbal medicinal candidate that able to develop drugs for osteoporosis. PMID:25409708

Siddiqui, Sahabjada; Arshad, Mohammad

2014-11-20

83

The Annual Cycle of the Energy Budget. Part I: Global Mean and LandOcean Exchanges  

E-print Network

radiances from the Earth Radiation Budget Experiment (ERBE) and Clouds and the Earth's Radiant Energy SystemThe Annual Cycle of the Energy Budget. Part I: Global Mean and Land­Ocean Exchanges JOHN T. FASULLO March, in final form 1 October 2007) ABSTRACT The mean and annual cycle of energy flowing

Fasullo, John

84

Dynamic Duty-Cycle Scheduling Schemes for Energy-Harvesting Wireless Sensor Networks  

Microsoft Academic Search

In this letter, we propose two novel dynamic duty-cycle scheduling schemes (called DSR and DSP) in order to reduce sleep latency, while achieving balanced energy consumption among sensor nodes in wireless sensor networks (WSNs) with energy harvesting capability. In DSR, each sensor node is allowed to adjust its duty-cycle according to the current amount of residual energy only. Since the

Hongseok Yoo; Moonjoo Shim; Dongkyun Kim

2012-01-01

85

Evaluation of high-energy lithium thionyl chloride primary cells  

NASA Technical Reports Server (NTRS)

An advanced commercial primary lithium cell (LiSoCl2) was evaluated in order to establish baseline data for improved lithium batteries for aerospace applications. The cell tested had nominal capacity of 6 Ah. Maximum energy density at low rates (less than C/30, where C is the cell capacity in amp-hrs and 30 corresponds to a 30 hr discharge time) was found to be near 300 Wh/kg. An equation which predicts the operating voltage of these cells as a function of current and state of charge is presented. Heat generation rates of these cells were determined as a function of current in a calorimeter. It was found that heat rates could be theoretically predicted with some degree of accuracy at currents less than 1 amp or the C/6 rate. No explosions were observed in the cells during the condition of overdischarge or reversal nor during high rate discharge. It was found, however, that the cells can vent when overdischarge currents are greater than C/30 and when discharge rates are greater than 1.5C.

Frank, H. A.

1980-01-01

86

Implications of incorporating N cycling and N limitations on primary production in an individual-based dynamic vegetation model  

NASA Astrophysics Data System (ADS)

The LPJ-GUESS dynamic vegetation model uniquely combines an individual- and patch-based representation of vegetation dynamics with ecosystem biogeochemical cycling from regional to global scales. We present an updated version that includes plant and soil N dynamics, analysing the implications of accounting for C-N interactions on predictions and performance of the model. Stand structural dynamics and allometric scaling of tree growth suggested by global databases of forest stand structure and development were well reproduced by the model in comparison to an earlier multi-model study. Accounting for N cycle dynamics improved the goodness of fit for broadleaved forests. N limitation associated with low N-mineralisation rates reduces productivity of cold-climate and dry-climate ecosystems relative to mesic temperate and tropical ecosystems. In a model experiment emulating free-air CO2 enrichment (FACE) treatment for forests globally, N limitation associated with low N-mineralisation rates of colder soils reduces CO2 enhancement of net primary production (NPP) for boreal forests, while some temperate and tropical forests exhibit increased NPP enhancement. Under a business-as-usual future climate and emissions scenario, ecosystem C storage globally was projected to increase by ca. 10%; additional N requirements to match this increasing ecosystem C were within the high N supply limit estimated on stoichiometric grounds in an earlier study. Our results highlight the importance of accounting for C-N interactions in studies of global terrestrial N cycling, and as a basis for understanding mechanisms on local scales and in different regional contexts.

Smith, B.; Wårlind, D.; Arneth, A.; Hickler, T.; Leadley, P.; Siltberg, J.; Zaehle, S.

2014-04-01

87

Open cycle ocean thermal energy conversion system structure  

DOEpatents

A generally mushroom-shaped, open cycle OTEC system and distilled water producer which has a skirt-conduit structure extending from the enlarged portion of the mushroom to the ocean. The enlarged part of the mushroom houses a toroidal casing flash evaporator which produces steam which expands through a vertical rotor turbine, partially situated in the center of the blossom portion and partially situated in the mushroom's stem portion. Upon expansion through the turbine, the motive steam enters a shell and tube condenser annularly disposed about the rotor axis and axially situated beneath the turbine in the stem portion. Relatively warm ocean water is circulated up through the radially outer skirt-conduit structure entering the evaporator through a radially outer portion thereof, flashing a portion thereof into motive steam, and draining the unflashed portion from the evaporator through a radially inner skirt-conduit structure. Relatively cold cooling water enters the annular condenser through the radially inner edge and travels radially outwardly into a channel situated along the radially outer edge of the condenser. The channel is also included in the radially inner skirt-conduit structure. The cooling water is segregated from the potable, motive steam condensate which can be used for human consumption or other processes requiring high purity water. The expansion energy of the motive steam is partially converted into rotational mechanical energy of the turbine rotor when the steam is expanded through the shaft attached blades. Such mechanical energy drives a generator also included in the enlarged mushroom portion for producing electrical energy. Such power generation equipment arrangement provides a compact power system from which additional benefits may be obtained by fabricating the enclosing equipment, housings and component casings from low density materials, such as prestressed concrete, to permit those casings and housings to also function as a floating support vessel.

Wittig, J. Michael (West Goshen, PA)

1980-01-01

88

Critical role for the kinesin KIF3A in the HIV life cycle in primary human macrophages  

PubMed Central

Macrophages are long-lived target cells for HIV infection and are considered viral reservoirs. HIV assembly in macrophages occurs in virus-containing compartments (VCCs) in which virions accumulate and are stored. The regulation of the trafficking and release of these VCCs remains unknown. Using high resolution light and electron microscopy of HIV-1–infected primary human macrophages, we show that the spatial distribution of VCCs depended on the microtubule network and that VCC-limiting membrane was closely associated with KIF3A+ microtubules. Silencing KIF3A strongly decreased virus release from HIV-1–infected macrophages, leading to VCC accumulation intracellularly. Time-lapse microscopy further suggested that VCCs and associated KIF3A move together along microtubules. Importantly, KIF3A does not play a role in HIV release from T cells that do not possess VCCs. These results reveal that HIV-1 requires the molecular motor KIF3 to complete its cycle in primary macrophages. Targeting this step may lead to novel strategies to eliminate this viral reservoir. PMID:23091068

Gaudin, Raphaël; Cunha de Alencar, Bruna; Jouve, Mabel; Bèrre, Stefano; Le Bouder, Emmanuel; Schindler, Michael; Varthaman, Aditi; Gobert, François-Xavier

2012-01-01

89

An ARL3-UNC119-RP2 GTPase cycle targets myristoylated NPHP3 to the primary cilium.  

PubMed

The membrane of the primary cilium is a highly specialized compartment that organizes proteins to achieve spatially ordered signaling. Disrupting ciliary organization leads to diseases called ciliopathies, with phenotypes ranging from retinal degeneration and cystic kidneys to neural tube defects. How proteins are selectively transported to and organized in the primary cilium remains unclear. Using a proteomic approach, we identified the ARL3 effector UNC119 as a binding partner of the myristoylated ciliopathy protein nephrocystin-3 (NPHP3). We mapped UNC119 binding to the N-terminal 200 residues of NPHP3 and found the interaction requires myristoylation. Creating directed mutants predicted from a structural model of the UNC119-myristate complex, we identified highly conserved phenylalanines within a hydrophobic ? sandwich to be essential for myristate binding. Furthermore, we found that binding of ARL3-GTP serves to release myristoylated cargo from UNC119. Finally, we showed that ARL3, UNC119b (but not UNC119a), and the ARL3 GAP Retinitis Pigmentosa 2 (RP2) are required for NPHP3 ciliary targeting and that targeting requires UNC119b myristoyl-binding activity. Our results uncover a selective, membrane targeting GTPase cycle that delivers myristoylated proteins to the ciliary membrane and suggest that other myristoylated proteins may be similarly targeted to specialized membrane domains. PMID:22085962

Wright, Kevin J; Baye, Lisa M; Olivier-Mason, Anique; Mukhopadhyay, Saikat; Sang, Liyun; Kwong, Mandy; Wang, Weiru; Pretorius, Pamela R; Sheffield, Val C; Sengupta, Piali; Slusarski, Diane C; Jackson, Peter K

2011-11-15

90

An ARL3–UNC119–RP2 GTPase cycle targets myristoylated NPHP3 to the primary cilium  

PubMed Central

The membrane of the primary cilium is a highly specialized compartment that organizes proteins to achieve spatially ordered signaling. Disrupting ciliary organization leads to diseases called ciliopathies, with phenotypes ranging from retinal degeneration and cystic kidneys to neural tube defects. How proteins are selectively transported to and organized in the primary cilium remains unclear. Using a proteomic approach, we identified the ARL3 effector UNC119 as a binding partner of the myristoylated ciliopathy protein nephrocystin-3 (NPHP3). We mapped UNC119 binding to the N-terminal 200 residues of NPHP3 and found the interaction requires myristoylation. Creating directed mutants predicted from a structural model of the UNC119–myristate complex, we identified highly conserved phenylalanines within a hydrophobic ? sandwich to be essential for myristate binding. Furthermore, we found that binding of ARL3-GTP serves to release myristoylated cargo from UNC119. Finally, we showed that ARL3, UNC119b (but not UNC119a), and the ARL3 GAP Retinitis Pigmentosa 2 (RP2) are required for NPHP3 ciliary targeting and that targeting requires UNC119b myristoyl-binding activity. Our results uncover a selective, membrane targeting GTPase cycle that delivers myristoylated proteins to the ciliary membrane and suggest that other myristoylated proteins may be similarly targeted to specialized membrane domains. PMID:22085962

Wright, Kevin J.; Baye, Lisa M.; Olivier-Mason, Anique; Mukhopadhyay, Saikat; Sang, Liyun; Kwong, Mandy; Wang, Weiru; Pretorius, Pamela R.; Sheffield, Val C.; Sengupta, Piali; Slusarski, Diane C.; Jackson, Peter K.

2011-01-01

91

Present and future status of thermochemical cycles applied to fusion energy sources  

SciTech Connect

This paper reviews the status of current research on thermochemical hydrogen production cycles and identifies the needs for advanced cycles and materials research. The Los Alamos Scientific Laboratory (LASL) bismuth sulfate thermochemical cycle is characterized, and fusion reactor blanket concepts for both inertial and magnetic confinement schemes are presented as thermal energy sources for process heat applications.

Booth, L.A.; Cox, K.E.; Krakowski, R.A.; Pendergrass, J.H.

1980-01-01

92

Exergoeconomic analysis of solar organic rankine cycle for geothermal air conditioned net zero energy buildings  

Microsoft Academic Search

This study is an attempt at achieving Net Zero Energy Building (NZEB) using a solar Organic Rankine Cycle (ORC) based on exergetic and economic measures. The working fluid, working conditions of the cycle, cycle configuration, and solar collector type are considered the optimization parameters for the solar ORC system. ^ In the first section, a procedure is developed to compare

Rambod Rayegan

2011-01-01

93

A Feasibility Study of CO2Based Rankine Cycle Powered by Solar Energy  

Microsoft Academic Search

An experiment study was carried out in order to investigate feasibility of CO2-based Rankine cycle powered by solar energy. The proposed cycle is to achieve a cogeneration of heat and power, which consists of evacuated solar tube collectors, power generating turbine, heat recovery system, and feed pump. The Rankine cycle of the system utilizes solar collectors to convert CO2 into

Xin-Rong Zhang; Hiroshi Yamaguchi; Katsumi Fujima; Masatoshi Enomoto; Noboru Sawada

2005-01-01

94

The NASA Energy and Water cycle Extreme (NEWSE) Integration Project  

NASA Astrophysics Data System (ADS)

Skillful predictions of water and energy cycle extremes (flood and drought) are elusive. To better understand the mechanisms responsible for water and energy extremes, and to make decisive progress in predicting these extremes, the collaborative NASA Energy and Water cycle Extremes (NEWSE) Integration Project, is studying these extremes in the U.S. Southern Great Plains (SGP) during 2006-2007, including their relationships with continental and global scale processes, and assessment of their predictability on multiple space and time scales. It is our hypothesis that an integrative analysis of observed extremes which reflects the current understanding of the role of SST and soil moisture variability influences on atmospheric heating and forcing of planetary waves, incorporating recently available global and regional hydro- meteorological datasets (i.e., precipitation, water vapor, clouds, etc.) in conjunction with advances in data assimilation, can lead to new insights into the factors that lead to persistent drought and flooding. We will show initial results of this project, whose goals are toprovide an improved definition, attribution and prediction on sub-seasonal to interannual time scales, improved understanding of the mechanisms of decadal drought and its predictability, including the impacts of SST variability and deep soil moisture variability, and improved monitoring/attributions, with transition to applications; a bridging of the gap between hydrological forecasts and stakeholders (utilization of probabilistic forecasts, education, forecast interpretation for different sectors, assessment of uncertainties for different sectors, etc.). *The NEWSE Team is: Romanou, Anastasiam, Columbia U.; Brian Soden, U. Miami; William Lapenta, NASA- MSFC; Megan Larko, CREW; Bing Lin, NASA-LaRC; Christa Peters-Lidard, NASA-GSFC; Xiquan Dong, U. North Dakota; Debbie Belvedere, CREW; Mathew Sapiano, U. Maryland; Duane Waliser, NASA-JPL; Eni Njoku, NASA/JPL; Eric Fetzer, NASA-JPL; Eyal Amitai, NASA-GSFC; Xiaogang Gao, U. California, Irvine; George Huffman, NASA-GSFC & SSAI; Jared Entin, NASA; Joseph Santanello, NASA-GSFC; John Roads, UCSD; W. Timothy Liu, NASA-JPL; Lixin Lu, Colorado State U.; Zhengzhao Luo, Colorado State U.; Michael Bosilovich, NASA-GSFC; Michael Jasinski, NASA-GSFC; William Olson, NASA-GSFC & UMBC-GEST; Pete Robertson, NASA-MSFC; Phil Arkin, U. Maryland; Paul Houser, CREW & GMU; Ralph Ferraro, NOAA; Pete Robertson, NASA-MSFC; Robert Schiffer; UMBC-GEST; Sujay Kumar, NASA-GSFC; Joseph A. Santanello, NASA-GSFC; Tristan L'Ecuyer, Colorado State U.; Wei-Kuo Tao; NASA-GSFC; Xia Feng; George Mason U.

Houser, P. R.; Lapenta, W.; Schiffer, R.

2008-05-01

95

Transporting carbon dioxide recovered from fossil-energy cycles  

SciTech Connect

Transportation of carbon dioxide (CO{sub 2}) for enhanced oil recovery is a mature technology, with operating experience dating from the mid-1980s. Because of this maturity, recent sequestration studies for the US Department of Energy's National Energy Technology Laboratory have been able to incorporate transportation into overall energy-cycle economics with reasonable certainty. For these studies, two different coal-fueled plants are considered; the first collects CO{sub 2} from a 456-MW integrated coal gasification combined-cycle plant, while the second employs a 353-MW pulverized-coal boiler plant retrofitted for flue-gas recycling (Doctor et al. 1999; MacDonald and Palkes 1999). The pulverized-coal plant fires a mixture of coal in a 33% O{sub 2} atmosphere, the bulk of the inert gas being made up to CO{sub 2} to the greatest extent practical. If one power plant with one pipe feeds one sequestration reservoir, projected costs for a 500-km delivery pipeline are problematic, because when supplying one reservoir both plant availability issues and useful pipeline life heavily influence capital recovery costs. The transportation system proposed here refines the sequestration scheme into a network of three distinctive pipelines: (1) 80-km collection pipelines for a 330-MW pulverized-coal power plant with 100% CO{sub 2} recovery; (2) a main CO{sub 2} transportation trunk of 320 km that aggregates the CO{sub 2} from four such plants; and (3) an 80-km distribution network. A 25-year life is assumed for the first two segments, but only half that for the distribution to the reservoir. Projected costs for a 500-km delivery pipeline, assuming an infrastructure, are $7.82/tonne ($17.22/10{sup 3} Nm{sub 3} CO{sub 2} or $0.49/10{sup 3} scf CO{sub 2}), a savings of nearly 60% with respect to base-case estimates with no infrastructure. These costs are consistent only with conditioned CO{sub 2} having low oxygen and sulfur content; they do not include CO{sub 2} recovery, drying, and compression.

Doctor, R. D.; Molburg, J. C.; Brockmeier, J. F.

2000-07-24

96

Large Scale Duty Cycle (LSDC) Project: Tractive Energy Analysis Methodology and Results from Long-Haul Truck Drive Cycle Evaluations  

SciTech Connect

This report addresses the approach that will be used in the Large Scale Duty Cycle (LSDC) project to evaluate the fuel savings potential of various truck efficiency technologies. The methods and equations used for performing the tractive energy evaluations are presented and the calculation approach is described. Several representative results for individual duty cycle segments are presented to demonstrate the approach and the significance of this analysis for the project. The report is divided into four sections, including an initial brief overview of the LSDC project and its current status. In the second section of the report, the concepts that form the basis of the analysis are presented through a discussion of basic principles pertaining to tractive energy and the role of tractive energy in relation to other losses on the vehicle. In the third section, the approach used for the analysis is formalized and the equations used in the analysis are presented. In the fourth section, results from the analysis for a set of individual duty cycle measurements are presented and different types of drive cycles are discussed relative to the fuel savings potential that specific technologies could bring if these drive cycles were representative of the use of a given vehicle or trucking application. Additionally, the calculation of vehicle mass from measured torque and speed data is presented and the accuracy of the approach is demonstrated.

LaClair, Tim J [ORNL

2011-05-01

97

LIFE CYCLE ANALYSIS OF HIGH-PERFORMANCE MONOCRYSTALLINE SILICON PHOTOVOLTAIC SYSTEMS: ENERGY PAYBACK TIMES AND NET ENERGY PRODUCTION VALUE  

E-print Network

LIFE CYCLE ANALYSIS OF HIGH-PERFORMANCE MONOCRYSTALLINE SILICON PHOTOVOLTAIC SYSTEMS: ENERGY-344-3957, vmf5@columbia.edu 2 Center for Life Cycle Analysis, Columbia University, New York, NY 10027, USA 3 SunPower Corporation, San Jose, CA, USA ABSTRACT: This paper summarizes a comprehensive life cycle analysis based

98

Response Surface Energy Modeling of an Electric Vehicle over a Reduced Composite Drive Cycle  

SciTech Connect

Response surface methodology (RSM) techniques were applied to develop a predictive model of electric vehicle (EV) energy consumption over the Environmental Protection Agency's (EPA) standardized drive cycles. The model is based on measurements from a synthetic composite drive cycle. The synthetic drive cycle is a minimized statistical composite of the standardized urban (UDDS), highway (HWFET), and US06 cycles. The composite synthetic drive cycle is 20 minutes in length thereby reducing testing time of the three standard EPA cycles by over 55%. Vehicle speed and acceleration were used as model inputs for a third order least squared regression model predicting vehicle battery power output as a function of the drive cycle. The approach reduced three cycles and 46 minutes of drive time to a single test of 20 minutes. Application of response surface modeling to the synthetic drive cycle is shown to predict energy consumption of the three EPA cycles within 2.6% of the actual measured values. Additionally, the response model may be used to predict energy consumption of any cycle within the speed/acceleration envelope of the synthetic cycle. This technique results in reducing test time, which additionally provides a model that may be used to expand the analysis and understanding of the vehicle under consideration.

Jehlik, Forrest [Argonne National Laboratory (ANL)] [Argonne National Laboratory (ANL); LaClair, Tim J [ORNL] [ORNL

2014-01-01

99

Cromer Cycle Air Conditioner: A Unique Air-Conditioner Desiccant Cycle to Enhance Dehumidification and Save Energy  

E-print Network

The Cromer cycle uses a desiccant to move moisture from the saturated air leaving an air conditioning (AC) cooling coil to the air returning to the AC unit from the conditioned space. This has the thermodynamic effect of reducing the overall energy...

Cromer, C. J.

2000-01-01

100

Open-cycle ocean thermal energy conversion surface-condenser design analysis and computer program  

NASA Astrophysics Data System (ADS)

This report documents a computer program for designing a surface condenser that condenses low-pressure steam in an ocean thermal energy conversion (OTEC) power plant. The primary emphasis is on the open-cycle (OC) OTEC power system, although the same condenser design can be used for conventional and hybrid cycles because of their highly similar operating conditions. In an OC-OTEC system, the pressure level is very low (deep vacuums), temperature differences are small, and the inlet noncondensable gas concentrations are high. Because current condenser designs, such as the shell-and-tube, are not adequate for such conditions, a plate-fin configuration is selected. This design can be implemented in aluminum, which makes it very cost-effective when compared with other state-of-the-art vacuum steam condenser designs. Support for selecting a plate-fin heat exchanger for OC-OTEC steam condensation can be found in the sizing (geometric details) and rating (heat transfer and pressure drop) calculations presented. These calculations are then used in a computer program to obtain all the necessary thermal performance details for developing design specifications for a plate-fin steam condenser.

Panchal, C. B.; Rabas, T. J.

1991-05-01

101

Comparison of energy-based indicators used in life cycle assessment tools for buildings  

EPA Science Inventory

Traditionally, building rating systems focused on, among others, energy used during operational stage. Recently, there is a strong push by these rating systems to include the life cycle energy use of buildings, particularly using Life Cycle Assessment (LCA), by offering credits t...

102

Life Cycle Assessment of electricity production from poplar energy crops compared with conventional fossil fuels  

Microsoft Academic Search

The environmental impact of electric power production through an Integrated Gasification Combined Cycle (IGCC) fired by dedicated energy crops (poplar Short Rotation Forestry (SRF)) is analysed by a Life Cycle Assessment approach. The results are compared with the alternative option of producing power by conventional fossil fueled power plants. The energy and raw materials consumption and polluting emissions data both

Angelantonio Rafaschieri; Mario Rapaccini; Giampaolo Manfrida

1999-01-01

103

A combined power cycle utilizing low-temperature waste heat and LNG cold energy  

Microsoft Academic Search

This paper has proposed a combined power system, in which low-temperature waste heat can be efficiently recovered and cold energy of liquefied natural gas (LNG) can be fully utilized as well. This system consists of an ammonia–water mixture Rankine cycle and an LNG power generation cycle, and it is modelled by considering mass, energy and species balances for every component

Xiaojun Shi; Defu Che

2009-01-01

104

A general ecosystem model for applications to primary productivity and carbon cycle studies in the global oceans  

NASA Astrophysics Data System (ADS)

We have developed a general 1-D multi-component ecosystem model that incorporates a skillful upper ocean mixed layer model based on second moment closure of turbulence. The model is intended for eventual incorporation into coupled 3-D physical-biogeochemical ocean models with potential applications to modeling and studying primary productivity and carbon cycling in the global oceans as well as to promote the use of chlorophyll concentrations, in concert with satellite-sensed ocean color, as a diagnostic tool to delineate circulation features in numerical circulation models. The model is nitrogen-based and the design is deliberately general enough and modular to enable many of the existing ecosystem model formulations to be simulated and hence model-to-model comparisons rendered feasible. In its more general form (GEM10), the model solves for nitrate, ammonium, dissolved nitrogen, bacteria and two size categories of phytoplankton, zooplankton and detritus, in addition to solving for dissolved inorganic carbon and total alkalinity to enable estimation of the carbon dioxide flux at the air-sea interface. Dissolved oxygen is another prognostic variable enabling air-sea exchange of oxygen to be calculated. For potential applications to HNLC regions where productivity is constrained by the availability of a trace constituent such as iron, the model carries the trace constituent as an additional prognostic variable. Here we present 1-D model simulations for the Black Sea, Station PAPA and the BATS site. The Black Sea simulations assimilate seasonal monthly SST, SSS and surface chlorophyll, and the seasonal modulations compare favorably with earlier work. Station PAPA simulations for 1975-1977 with GEM5 assimilating observed SST and a plausible seasonal modulation of surface chlorophyll concentration also compare favorably with earlier work and with the limited observations on nitrate and pCO 2 available. Finally, GEM5 simulations at BATS for 1985-1997 are consistent with the available time series. The simulations suggest that while it is generally desirable to employ a comprehensive ecosystem model with a large number of components when accurate depiction of the entire ecosystem is desirable, as is the prevailing practice, a simpler formulation such as GEM5 (N 2PZD model) combined with assimilation of remotely sensed SST and chlorophyll concentrations may suffice for incorporation into 3-D prediction models of primary productivity, upper ocean optical clarity and carbon cycling.

Kantha, Lakshmi H.

105

A fuel cycle assessment guide for utility and state energy planners  

SciTech Connect

This guide, one in a series of documents designed to help assess fuel cycles, is a framework for setting parameters, collecting data, and analyzing fuel cycles for supply-side and demand-side management. It provides an automated tool for entering comparative fuel cycle data that are meaningful to state and utility integrated resource planning, collaborative, and regional energy planning activities. It outlines an extensive range of energy technology characteristics and environmental, social, and economic considerations within each stage of a fuel cycle. The guide permits users to focus on specific stages or effects that are relevant to the technology being evaluated and that meet the user`s planning requirements.

Not Available

1994-07-01

106

University of Minnesota aquifer thermal energy storage (ATES) project report on the second long-term cycle  

SciTech Connect

The technical feasibility of high-temperature (>100{degrees}C (>212{degrees}F)) aquifer thermal energy storage (ATES) in a deep, confined aquifer was tested in a series of experimental cycles at the University of Minnesota's St. Paul field test facility (FTF). This report describes the second long-term cycle (LT2), which was conducted from October 1986 through April 1987. Heat recovery; operational experience; and thermal, chemical, hydrologic, and geologic effects are reported. Approximately 61% of the 9.21 GWh of energy added to the 9.38 {times} 10{sup 4} m{sup 3} of ground water stored during LT2 was recovered. Temperatures of the water stored and recovered averaged 118{degrees}C (244{degrees}F) and 85{degrees}C (185{degrees}F), respectively. Results agreed with previous cycles conducted at the FTF. System operation during LT2 was nearly as planned. Operational experience from previous cycles at the FTF was extremely helpful. Ion-exchange softening of the heated and stored aquifer water prevented scaling in the system heat exchangers and the storage well, and changed the major-ion chemistry of the stored water. Sodium bicarbonate replaced magnesium and calcium bicarbonate as primary ions in the softened water. Water recovered form storage was approximately at equilibrium with respect to dissolved ions. Silica, calcium, and magnesium were significantly higher in recovered water than in injected water. Sodium was significantly lower in water recovered than in water stored.

Hoyer, M.C.; Hallgren, J.P.; Lauer, J.L.; Walton, M.; Eisenreich, S.J.; Howe, J.T.; Splettstoesser, J.F. (Minnesota Geological Survey, St. Paul, MN (United States))

1991-12-01

107

University of Minnesota aquifer thermal energy storage (ATES) project report on the second long-term cycle  

SciTech Connect

The technical feasibility of high-temperature [>100{degrees}C (>212{degrees}F)] aquifer thermal energy storage (ATES) in a deep, confined aquifer was tested in a series of experimental cycles at the University of Minnesota`s St. Paul field test facility (FTF). This report describes the second long-term cycle (LT2), which was conducted from October 1986 through April 1987. Heat recovery; operational experience; and thermal, chemical, hydrologic, and geologic effects are reported. Approximately 61% of the 9.21 GWh of energy added to the 9.38 {times} 10{sup 4} m{sup 3} of ground water stored during LT2 was recovered. Temperatures of the water stored and recovered averaged 118{degrees}C (244{degrees}F) and 85{degrees}C (185{degrees}F), respectively. Results agreed with previous cycles conducted at the FTF. System operation during LT2 was nearly as planned. Operational experience from previous cycles at the FTF was extremely helpful. Ion-exchange softening of the heated and stored aquifer water prevented scaling in the system heat exchangers and the storage well, and changed the major-ion chemistry of the stored water. Sodium bicarbonate replaced magnesium and calcium bicarbonate as primary ions in the softened water. Water recovered form storage was approximately at equilibrium with respect to dissolved ions. Silica, calcium, and magnesium were significantly higher in recovered water than in injected water. Sodium was significantly lower in water recovered than in water stored.

Hoyer, M.C.; Hallgren, J.P.; Lauer, J.L.; Walton, M.; Eisenreich, S.J.; Howe, J.T.; Splettstoesser, J.F. [Minnesota Geological Survey, St. Paul, MN (United States)

1991-12-01

108

Absorption Cycle Fundamentals and Applications Guidelines for Distillation Energy Savings  

E-print Network

The absorption cycle offers one of the most economic and widely applicable technologies for waste heat upgrading. It can use off-the-shelf hardware that is available now, at any required capacity rating. Fractional distillations, as a class...

Erickson, D. C.; Davidson, W. F.

1984-01-01

109

Carcinogens induce loss of the primary cilium in human renal proximal tubular epithelial cells independently of effects on the cell cycle  

PubMed Central

The primary cilium is an immotile sensory and signaling organelle found on the majority of mammalian cell types. Of the multitude of roles that the primary cilium performs, perhaps some of the most important include maintenance of differentiation, quiescence, and cellular polarity. Given that the progression of cancer requires disruption of all of these processes, we have investigated the effects of several carcinogens on the primary cilium of the RPTEC/TERT1 human proximal tubular epithelial cell line. Using both scanning electron microscopy and immunofluorescent labeling of the ciliary markers acetylated tubulin and Arl13b, we confirmed that RPTEC/TERT1 cells express primary cilium upon reaching confluence. Treatment with the carcinogens ochratoxin A (OTA) and potassium bromate (KBrO3) caused a significant reduction in the number of ciliated cells, while exposure to nifedipine, a noncarcinogenic renal toxin, had no effect on primary cilium expression. Flow cytometric analysis of the effects of all three compounds on the cell cycle revealed that only KBrO3 resulted in an increase in the proportion of cells entering the cell cycle. Microarray analysis revealed dysregulation of multiple pathways affecting ciliogenesis and ciliary maintenance following OTA and KBrO3 exposure, which were unaffected by nifedipine exposure. The primary cilium represents a unique physical checkpoint with relevance to carcinogenesis. We have shown that the renal carcinogens OTA and KBrO3 cause significant deciliation in a model of the proximal tubule. With KBrO3, this was followed by reentry into the cell cycle; however, deciliation was not found to be associated with reentry into the cell cycle following OTA exposure. Transcriptomic analysis identified dysregulation of Wnt signaling and ciliary trafficking in response to OTA and KBrO3 exposure. PMID:22262483

Radford, Robert; Slattery, Craig; Jennings, Paul; Blacque, Oliver; Pfaller, Walter; Gmuender, Hans; Van Delft, Joost; Ryan, Michael P.

2012-01-01

110

Carcinogens induce loss of the primary cilium in human renal proximal tubular epithelial cells independently of effects on the cell cycle.  

PubMed

The primary cilium is an immotile sensory and signaling organelle found on the majority of mammalian cell types. Of the multitude of roles that the primary cilium performs, perhaps some of the most important include maintenance of differentiation, quiescence, and cellular polarity. Given that the progression of cancer requires disruption of all of these processes, we have investigated the effects of several carcinogens on the primary cilium of the RPTEC/TERT1 human proximal tubular epithelial cell line. Using both scanning electron microscopy and immunofluorescent labeling of the ciliary markers acetylated tubulin and Arl13b, we confirmed that RPTEC/TERT1 cells express primary cilium upon reaching confluence. Treatment with the carcinogens ochratoxin A (OTA) and potassium bromate (KBrO(3)) caused a significant reduction in the number of ciliated cells, while exposure to nifedipine, a noncarcinogenic renal toxin, had no effect on primary cilium expression. Flow cytometric analysis of the effects of all three compounds on the cell cycle revealed that only KBrO(3) resulted in an increase in the proportion of cells entering the cell cycle. Microarray analysis revealed dysregulation of multiple pathways affecting ciliogenesis and ciliary maintenance following OTA and KBrO(3) exposure, which were unaffected by nifedipine exposure. The primary cilium represents a unique physical checkpoint with relevance to carcinogenesis. We have shown that the renal carcinogens OTA and KBrO(3) cause significant deciliation in a model of the proximal tubule. With KBrO(3), this was followed by reentry into the cell cycle; however, deciliation was not found to be associated with reentry into the cell cycle following OTA exposure. Transcriptomic analysis identified dysregulation of Wnt signaling and ciliary trafficking in response to OTA and KBrO(3) exposure. PMID:22262483

Radford, Robert; Slattery, Craig; Jennings, Paul; Blacque, Oliver; Blaque, Oliver; Pfaller, Walter; Gmuender, Hans; Van Delft, Joost; Ryan, Michael P; McMorrow, Tara

2012-04-15

111

Analysis on Correlation Relationship Between Life Cycle Greenhouse Gas Emission and Life Cycle Cost of Electricity Generation System for Energy Resources  

Microsoft Academic Search

\\u000a In this work, we analysed correlations between life cycle greenhouse gas (GHG) emissions and life cycle cost of energy resources.\\u000a Energy resources studied in this paper include coal, natural gas, nuclear power, hydropower, geothermal energy, wind power,\\u000a solar thermal energy, and solar photovoltaic energy, and all of them are used to generate electricity. We calculated the mean\\u000a values, ranges of

Heetae Kim; Tae Kyu Ahn

112

Life cycle cost-based risk model for energy performance contracting retrofits  

NASA Astrophysics Data System (ADS)

Buildings account for 41% of the primary energy consumption in the United States, nearly half of which is accounted for by commercial buildings. Among the greatest energy users are those in the municipalities, universities, schools, and hospitals (MUSH) market. Correctional facilities are in the upper half of all commercial building types for energy intensity. Public agencies have experienced reduced capital budgets to fund retrofits; this has led to the increased use of energy performance contracts (EPC), which are implemented by energy services companies (ESCOs). These companies guarantee a minimum amount of energy savings resulting from the retrofit activities, which in essence transfers performance risk from the owner to the contractor. Building retrofits in the MUSH market, especially correctional facilities, are well-suited to EPC, yet despite this potential and their high energy intensities, efficiency improvements lag behind that of other public building types. Complexities in project execution, lack of support for data requests and sub-metering, and conflicting project objectives have been cited as reasons for this lag effect. As a result, project-level risks must be understood in order to support wider adoption of retrofits in the public market, in particular the correctional facility sub-market. The goal of this research is to understand risks related to the execution of energy efficiency retrofits delivered via EPC in the MUSH market. To achieve this goal, in-depth analysis and improved understanding was sought with regard to ESCO risks that are unique to EPC in this market. The proposed work contributes to this understanding by developing a life cycle cost-based risk model to improve project decision making with regard to risk control and reduction. The specific objectives of the research are: (1) to perform an exploratory analysis of the EPC retrofit process and identify key areas of performance risk requiring in-depth analysis; (2) to construct a framework describing the sources of and mitigation strategies employed for assessing key risks in EPC retrofits; (3) to develop a strategy for analyzing and evaluating risks for EPC retrofits focused on managing expected costs throughout the project life cycle, and use data collected through this strategy to develop and parameterize a risk model; and (4) to demonstrate the applicability of the proposed life cost-based risk model through a pilot application to a case study site. Five major contributions to the body of knowledge resulting from the research include: (1) a consensus-based assessment of ESCO risk management; (2) characterization of EPC retrofit risks borne by ESCOs; (3) an empirical evaluation of scenario failure mode and effects analysis and its application to this domain; (4) development and pilot application of a life cycle cost-based risk model; and (5) future expansion of the research approach to other domains. The researcher envisions that full implementation of the research will further encourage the growth of the energy services industry, and support focused retrofits in complex building types that typically can benefit the most from such work. Ultimately, this will reduce the energy consumption of public sector buildings to levels that are more fitting with the global principles of sustainability and responsible management of constrained resources.

Berghorn, George H.

113

Development and use of the GREET model to estimate fuel-cycle energy use and emissions of various transportation technologies and fuels  

SciTech Connect

This report documents the development and use of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel- cycle emissions and energy use associated with various transportation fuels for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides, sulfur oxides, and particulate matter measuring 10 microns or less) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates the total fuel-cycle energy consumption, fossil fuel consumption, and petroleum consumption using various transportation fuels. The GREET model includes 17 fuel cycles: petroleum to conventional gasoline, reformulated gasoline, clean diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to compressed natural gas, liquefied petroleum gas, methanol, hydrogen, and electricity; coal to electricity; uranium to electricity; renewable energy (hydrogen, solar energy, and wind) to electricity; corn, woody biomass, and herbaceous biomass to ethanol; and landfill gases to methanol. This report presents fuel-cycle energy use and emissions for a 2000 model-year car powered by each of the fuels that are produced from the primary energy sources considered in the study.

Wang, M.Q.

1996-03-01

114

Exergoeconomic Analysis of Solar Organic Rankine Cycle for Geothermal Air Conditioned Net Zero Energy Buildings  

Microsoft Academic Search

This study is an attempt at achieving Net Zero Energy Building (NZEB) using a solar Organic Rankine Cycle (ORC) based on exergetic and economic measures. The working fluid, working conditions of the cycle, cycle configuration, and solar collector type are considered the optimization parameters for the solar ORC system.\\u000aIn the first section, a procedure is developed to compare ORC

Rambod Rayegan

2011-01-01

115

Primary Photosynthetic Energy Conversion in Bacterial Reaction Centers  

NASA Astrophysics Data System (ADS)

The development of human societies is strongly influenced by the available energetic resources. In a period where the limitations of conventional fossil energy carriers become as evident as the often uncontrollable dangers of nuclear energy, one has to reconsider regenerative energy resources. Here photovoltaic or photochemical use of solar energy is an important approach. Since the early days of evolution some two billion years ago, the dominant energetic input into the life system on earth occurs via the conversion of solar energy performed in photosynthetic organisms. The fossil energy carriers that we use and waste today have been produced by photosynthesis over millions of years. In the race for an extended and versatile use of solar energy, semiconductorbased photovoltaic devices have been developed. However, even after decades of intense engineering they cannot serve as a competitive alternative to fossil energy. Under these circumstances new alternatives are required. One line of scientific development may use the operational principles of photosynthesis since photosynthesis is still our main energy source. In this respect, we will present results on the basic concepts of energy conversion in photosynthetic bacteria, which could be used as a guideline to alternative light energy conversion systems.

Zinth, Wolfgang; Wachtveitl, J.

116

Red waters of Myrionecta rubra are biogeochemical hotspots for the Columbia River estuary with impacts on primary/secondary productions and nutrient cycles  

SciTech Connect

The localized impact of blooms of the mixotrophic ciliate Myrionecta rubra in the Columbia River estuary during 2007-2010 was evaluated with biogeochemical, light microscopy, physiological and molecular data. M. rubra affected surrounding estuarine nutrient cycles, as indicated by high and low concentrations of organic nutrients and inorganic nitrogen, respectively, associated with red waters. M. rubra blooms also altered the energy transfer pattern in patches of the estuarine water that contain the ciliate by creating areas characterized by high primary production and elevated levels of fresh autochthonous particulate organic matter, therefore shifting the trophic status in emergent red water areas of the estuary from net heterotrophy towards autotrophy. The pelagic estuarine bacterial community structure was unaffected by M. rubra abundance, but red waters of the ciliate do offer a possible link between autotrophic and heterotrophic processes since they were associated with elevated dissolved organic matter and enhanced microbial secondary production. Taken together these findings suggest that M. rubra red waters are biogeochemical hotspots of the Columbia River estuary.

Herfort, Lydie; Peterson, Tawnya D.; Prahl, Fredrick G.; McCue, Lee Ann; Needoba, Joe A.; Crump, Byron C.; Roegner, G. Curtis; Campbell, Victoria; Zuber, Peter A.

2012-02-29

117

ENERGY EFFICIENCY LIMITS FOR A RECUPERATIVE BAYONET SULFURIC ACID DECOMPOSITION REACTOR FOR SULFUR CYCLE THERMOCHEMICAL HYDROGEN PRODUCTION  

SciTech Connect

A recuperative bayonet reactor design for the high-temperature sulfuric acid decomposition step in sulfur-based thermochemical hydrogen cycles was evaluated using pinch analysis in conjunction with statistical methods. The objective was to establish the minimum energy requirement. Taking hydrogen production via alkaline electrolysis with nuclear power as the benchmark, the acid decomposition step can consume no more than 450 kJ/mol SO{sub 2} for sulfur cycles to be competitive. The lowest value of the minimum heating target, 320.9 kJ/mol SO{sub 2}, was found at the highest pressure (90 bar) and peak process temperature (900 C) considered, and at a feed concentration of 42.5 mol% H{sub 2}SO{sub 4}. This should be low enough for a practical water-splitting process, even including the additional energy required to concentrate the acid feed. Lower temperatures consistently gave higher minimum heating targets. The lowest peak process temperature that could meet the 450-kJ/mol SO{sub 2} benchmark was 750 C. If the decomposition reactor were to be heated indirectly by an advanced gas-cooled reactor heat source (50 C temperature difference between primary and secondary coolants, 25 C minimum temperature difference between the secondary coolant and the process), then sulfur cycles using this concept could be competitive with alkaline electrolysis provided the primary heat source temperature is at least 825 C. The bayonet design will not be practical if the (primary heat source) reactor outlet temperature is below 825 C.

Gorensek, M.; Edwards, T.

2009-06-11

118

[Life cycle assessment of energy consumption and greenhouse gas emissions of cellulosic ethanol from corn stover].  

PubMed

Life Cycle Assessment (LCA) is the only standardized tool currently used to assess environmental loads of products and processes. The life cycle analysis, as a part of LCA, is a useful and powerful methodology for studying life cycle energy efficiency and life cycle GHG emission. To quantitatively explain the potential of energy saving and greenhouse gas (GHG) emissions reduction of corn stover-based ethanol, we analyzed life cycle energy consumption and GHG emissions of corn stover-based ethanol by the method of life cycle analysis. The processes are dilute acid prehydrolysis and enzymatic hydrolysis. The functional unit was defined as 1 km distance driven by the vehicle. Results indicated: compared with gasoline, the corn stover-based E100 (100% ethanol) and E10 (a blend of 10% ethanol and 90% gasoline by volume) could reduce life cycle fossil energy consumption by 79.63% and 6.25% respectively, as well as GHG emissions by 53.98% and 6.69%; the fossil energy consumed by biomass stage was 68.3% of total fossil energy input, N-fertilizer and diesel were the main factors which contributed 45.78% and 33.26% to biomass stage; electricity production process contributed 42.06% to the net GHG emissions, the improvement of technology might reduce emissions markedly. PMID:21650036

Tian, Wang; Liao, Cuiping; Li, Li; Zhao, Daiqing

2011-03-01

119

Characterization of the Interaction between Human Respiratory Syncytial Virus and the Cell Cycle in Continuous Cell Culture and Primary Human Airway Epithelial Cells?  

PubMed Central

Viruses can modify conditions inside cells to make them more favorable for replication and progeny virus production. One way of doing this is through manipulation of the cell cycle, a process that describes the ordered growth and division of cells. Analysis of model cell lines, such as A549 cells and primary airway epithelial cells, infected with human respiratory syncytial virus (HRSV) has shown alteration of the cell cycle during infection, although the signaling events were not clearly understood. In this study, targeted transcriptomic analysis of HRSV-infected primary airway epithelial cells revealed alterations in the abundances of many mRNAs encoding cell cycle-regulatory molecules, including decreases in the D-type cyclins and corresponding cyclin-dependent kinases (CDK4 and CDK6 [CDK4/6]). These alterations were reflected in changes in protein abundance and/or relocalization in HRSV-infected cells; taken together, they were predicted to result in G0/G1 phase arrest. In contrast, there was no change in the abundances of D-type cyclins in A549 cells infected with HRSV. However, the abundance of the G1/S phase progression inhibitor p21WAF1/CIP1 was increased over that in mock-treated cells, and this, again, was predicted to result in G0/G1 phase arrest. The G0/G1 phase arrest in both HRSV-infected primary cells and A549 cells was confirmed using dual-label flow cytometry that accurately measured the different stages of the cell cycle. Comparison of progeny virus production in primary and A549 cells enriched in G0/G1 using a specific CDK4/6 kinase inhibitor with asynchronously replicating cells indicated that this phase of the cell cycle was more efficient for virus production. PMID:21795354

Wu, Weining; Munday, Diane C.; Howell, Gareth; Platt, Gareth; Barr, John N.; Hiscox, Julian A.

2011-01-01

120

Prognostic Utility of Cell Cycle Progression Score in Men With Prostate Cancer After Primary External Beam Radiation Therapy  

SciTech Connect

Purpose: To evaluate the prognostic utility of the cell cycle progression (CCP) score, a RNA signature based on the average expression level of 31 CCP genes, for predicting biochemical recurrence (BCR) in men with prostate cancer treated with external beam radiation therapy (EBRT) as their primary curative therapy. Methods and Materials: The CCP score was derived retrospectively from diagnostic biopsy specimens of men diagnosed with prostate cancer from 1991 to 2006 (n=141). All patients were treated with definitive EBRT; approximately half of the cohort was African American. Outcome was time from EBRT to BCR using the Phoenix definition. Median follow-up for patients without BCR was 4.8 years. Association with outcome was evaluated by Cox proportional hazards survival analysis and likelihood ratio tests. Results: Of 141 patients, 19 (13%) had BCR. The median CCP score for patient samples was 0.12. In univariable analysis, CCP score significantly predicted BCR (P=.0017). The hazard ratio for BCR was 2.55 for 1-unit increase in CCP score (equivalent to a doubling of gene expression). In a multivariable analysis that included Gleason score, prostate-specific antigen, percent positive cores, and androgen deprivation therapy, the hazard ratio for CCP changed only marginally and remained significant (P=.034), indicating that CCP provides prognostic information that is not provided by standard clinical parameters. With 10-year censoring, the CCP score was associated with prostate cancer-specific mortality (P=.013). There was no evidence for interaction between CCP and any clinical variable, including ethnicity. Conclusions: Among men treated with EBRT, the CCP score significantly predicted outcome and provided greater prognostic information than was available with clinical parameters. If validated in a larger cohort, CCP score could identify high-risk men undergoing EBRT who may need more aggressive therapy.

Freedland, Stephen J., E-mail: steve.freedland@duke.edu [Department of Surgery, Durham VA Medical Center, Durham, North Carolina (United States); Department of Surgery (Urology), Duke University School of Medicine, Durham, North Carolina (United States); Department of Pathology, Duke University School of Medicine, Durham, North Carolina (United States); Gerber, Leah [Department of Surgery, Durham VA Medical Center, Durham, North Carolina (United States); Department of Surgery (Urology), Duke University School of Medicine, Durham, North Carolina (United States); Department of Pathology, Duke University School of Medicine, Durham, North Carolina (United States); Reid, Julia; Welbourn, William; Tikishvili, Eliso; Park, Jimmy; Younus, Adib; Gutin, Alexander; Sangale, Zaina; Lanchbury, Jerry S. [Myriad Genetics, Inc, Salt Lake City, Utah (United States); Salama, Joseph K. [Department of Radiation Oncology, Durham VA Medical Center, Durham, North Carolina (United States); Department of Radiation Oncology, Duke University School of Medicine, Durham, North Carolina (United States); Stone, Steven [Myriad Genetics, Inc, Salt Lake City, Utah (United States)

2013-08-01

121

OPTIMIZATION WITH ENERGY MANAGEMENT OF PV BATTERY STAND-ALONE SYSTEMS OVER THE ENTIRE LIFE CYCLE  

E-print Network

, to reduce cycling costs (sizable in the case of lead-acid batteries [1]) can in turn be optimized accordingOPTIMIZATION WITH ENERGY MANAGEMENT OF PV BATTERY STAND-ALONE SYSTEMS OVER THE ENTIRE LIFE CYCLE of working on averaged time series data using much narrower time intervals (e.g. 1-hour series). Design

Paris-Sud XI, Université de

122

Life cycle model of alternative fuel vehicles: emissions, energy, and cost trade-offs  

Microsoft Academic Search

This paper describes a life cycle model for performing level-playing field comparisons of the emissions, costs, and energy efficiency trade-offs of alternative fuel vehicles (AFV) through the fuel production chain and over a vehicle lifetime. The model is an improvement over previous models because it includes the full life cycle of the fuels and vehicles, free of the distorting effects

Jeremy Hackney; Richard de Neufville

2001-01-01

123

Life-cycle energy analyses of electric vehicle storage batteries. Final report  

SciTech Connect

The results of several life-cycle energy analyses of prospective electric vehicle batteries are presented. The batteries analyzed were: Nickel-zinc; Lead-acid; Nickel-iron; Zinc-chlorine; Sodium-sulfur (glass electrolyte); Sodium-sulfur (ceramic electrolyte); Lithium-metal sulfide; and Aluminum-air. A life-cycle energy analysis consists of evaluating the energy use of all phases of the battery's life, including the energy to build it, operate it, and any credits that may result from recycling of the materials in it. The analysis is based on the determination of three major energy components in the battery life cycle: Investment energy, i.e., The energy used to produce raw materials and to manufacture the battery; operational energy i.e., The energy consumed by the battery during its operational life. In the case of an electric vehicle battery, this energy is the energy required (as delivered to the vehicle's charging circuit) to power the vehicle for 100,000 miles; and recycling credit, i.e., The energy that could be saved from the recycling of battery materials into new raw materials. The value of the life-cycle analysis approach is that it includes the various penalties and credits associated with battery production and recycling, which enables a more accurate determination of the system's ability to reduce the consumption of scarce fuels. The analysis of the life-cycle energy requirements consists of identifying the materials from which each battery is made, evaluating the energy needed to produce these materials, evaluating the operational energy requirements, and evaluating the amount of materials that could be recycled and the energy that would be saved through recycling. Detailed descriptions of battery component materials, the energy requirements for battery production, and credits for recycling, and the operational energy for an electric vehicle, and the procedures used to determine it are discussed.

Sullivan, D; Morse, T; Patel, P; Patel, S; Bondar, J; Taylor, L

1980-12-01

124

FULL FUEL CYCLE ASSESSMENT: WELL-TO-WHEELS ENERGY INPUTS,  

E-print Network

Michael Scheible Dean Simeroth TIAX Matt Hooks Michael Jackson Jennifer Pont Dan Rutherford Larry Kenneth Koyama Michael McCormack Philip Misemer Suzanne Phinney Patty Rinaldi Elizabeth Sandoval Diana Waterland Stefan Unnasch FULL FUEL CYCLE ANALYSIS PEER REVIEWERS Argonne National Laboratory Michael Wang

125

FULL FUEL CYCLE ASSESSMENT WELL TO WHEELS ENERGY INPUTS,  

E-print Network

options for on road vehicle and off road equipment applications in California. Examining emissions on a full fuel cycle basis for alternative-fueled vehicles is important when assessing the overall environmental impact of these vehicles from both a global and local perspective. Emissions associated with fuel

126

From net energy to zero energy buildings: Defining life cycle zero energy buildings (LC-ZEB)  

Microsoft Academic Search

There are various definitions of ‘zero energy’ and ‘net-zero’ energy building. In most cases, the definitions refer only to the energy that is used in the operation of the building, ignoring the aspects of energy use related to the construction and delivery of the building and its components. On the other hand the concept of ‘net energy’ as used in

Patxi Hernandez; Paul Kenny

2010-01-01

127

Advanced Organic Vapor Cycles for Improving Thermal Conversion Efficiency in Renewable Energy Systems  

E-print Network

first and second law of thermodynamics and the definition of Helmholtz energy,First law-based thermodynamic analysis on Kalina cycle," Frontiers of Energyenergy, and its derivatives, the combined first and second law

Ho, Tony

2012-01-01

128

Life-Cycle Cost Analysis Highlights Hydrogen's Potential for Electrical Energy Storage (Fact Sheet)  

SciTech Connect

This fact sheet describes NREL's accomplishments in analyzing life-cycle costs for hydrogen storage in comparison with other energy storage technologies. Work was performed by the Hydrogen Technologies and Systems Center.

Not Available

2010-11-01

129

Potential Energy Savings from Optimized Schedule and Economizer Cycles in the Moody Library at UTMB  

E-print Network

This report presents the results of a study which was initiated in order to estimate the potential energy savings due to optimizing the HVAC operation schedule and using economizer cycles in the Moody Library Building located at the University...

Liu, M.; Athar, A.; Reddy, T. A.; Claridge, D. E.; Haberl, J. S.

1993-01-01

130

Biomass to hydrogen for the realization of closed cycles of energy resources  

Microsoft Academic Search

The crucial mission of energy research is the promotion and implementation of methods, technologies and processes for a sustainable economic and social development. Within this framework the key progress energy systems is the realization of Closed Cycles of Energy Resources—CCER, whose goal is to achieve zero consumption in terms of non-renewable resources and no impact on the environment. A CCER

Fabio Orecchini; Enrico Bocci

2007-01-01

131

CEC-500-2010-FS-XXX Life-Cycle Energy  

E-print Network

CEC-500-2010-FS-XXX Life-Cycle Energy Assessment of Smart Growth Strategies TRANSPORTATION ENERGY RESEARCH PIER Transportation Research www.energy.ca.gov/research/ transportation/ March 2011 The Issue roadways, parking lots, and fueling stations to support increased automobile travel. Conversely, smart

132

Advanced Organic Vapor Cycles for Improving Thermal Conversion Efficiency in Renewable Energy Systems  

E-print Network

first and second law of thermodynamics and the definition of Helmholtz energy,energy, and its derivatives, the combined first and second lawFirst and second law analysis of a new power and refrigeration thermodynamic cycle using solar heat source," Solar Energy,

Ho, Tony

2012-01-01

133

Analysis and Optimization of the Power Cycle Based on the Cold Energy of Liquefied Natural Gas  

Microsoft Academic Search

Liquid natural gas (LNG) delivered by sea-ships contains considerable cryogenic energy which can be used for power generation before its evaporation and introduction into the system of pipe line. Electric power generation utilizing LNG cold energy is a major research direction. There are two kinds of LNG cold energy utilization in electric power generation, that is, independent thermal cycle with

Lu Yuanwei; Yang Hongchang; Ma Chongfang

2011-01-01

134

BCR targets cyclin D2 via Btk and the p85? subunit of PI3-K to induce cell cycle progression in primary mouse B cells  

Microsoft Academic Search

The p85? subunit of PI3-K and Btk are two crucial components of the B-cell receptor (BCR) signalling pathway. In the present study, we showed that primary splenic B cells from p85? null and xid (Btk-deficient) mice fail to induce cyclin D2 expression and enter early G1, but not S phase of the cell cycle in response to BCR engagement. Furthermore,

Janet Glassford; Inês Soeiro; Sara M Skarell; Lolita Banerji; Mary Holman; Gerry G B Klaus; Takashi Kadowaki; Shigeo Koyasu; Eric W-F Lam; EW-F Lam

2003-01-01

135

The industrial life cycle of wind energy electrical power generation  

Microsoft Academic Search

This innovation assessment addresses the factors that have influenced the exceptionally lengthy industrial technology life cycle of wind electrical power generation since its inception in the late 19th Century. It then applies the recently developed Accelerated Radical Innovation (ARI) Model to understand the dynamics of this innovation compared to those of other major 18th–20th Century innovations.Despite market pull in the

John P. Dismukes; Lawrence K. Miller; John A. Bers

2009-01-01

136

Total energy-cycle energy and emissions impacts of hybrid electric vehicles  

SciTech Connect

Argonne National Laboratory has begun an analysis of the energy and air emission impacts of hybrid electric vehicles (HEVs) over the entire energy cycle, including manufacturing, operating, and recycling the vehicles and producing their fuel. Phase 1 evaluates series HEVs using lead acid and nickel metal hydride batteries, operating independent of the electricity grid and connected to it, and compares them to conventional ICE vehicles. With efficient electric components, both grid-dependent and grid-independent vehicles are more efficient than their conventional counterpart, though most of the efficiency advantage is gained in slow, lower power operation (e.g., on the federal urban driving schedule). The grid-independent HEV is not clearly superior if it operates part of each day with grid electricity. Finally, estimates of lead emissions for the lead acid battery-powered HEV are significantly lower than suggested elsewhere.

Wang, M.Q.; Plotkin, S.; Santini, D.J.; He, J.; Gaines, L. [Argonne National Lab., IL (United States). Center for Transportation Research; Patterson, P. [Dept. of Energy, Washington, DC (United States). Office of Transportation Technologies

1997-09-17

137

Energy from CO2 using capacitive electrodes - A model for energy extraction cycles.  

PubMed

A model is presented for the process of harvesting electrical energy from CO2 emissions using capacitive cells. The principle consists of controlling the mixing process of a concentrated CO2 gas stream with a dilute CO2 gas stream (as, for example, exhaust gas and air), thereby converting part of the released mixing energy into electrical energy. The model describes the transient reactive transport of CO2 gas absorbed in water or in monoethanolamine (MEA) solutions, under the assumption of local chemical equilibrium. The model combines the selective transport of ions through ion-exchange membranes, the accumulation of charge in the porous carbon electrodes and the coupling between the ionic current and the produced electrical current and power. We demonstrate that the model can be used to calculate the energy that can be extracted by mixing concentrated and dilute CO2 containing gas streams. Our calculation results for the process using MEA solutions have various counterintuitive features, including: 1. When dynamic equilibrium is reached in the cyclical process, the electrical charge in the anode is negative both during charging and discharging; 2. Placing an anion-exchange membrane (AEM) in the system is not required, the energy per cycle is just as large with or without an AEM. PMID:25525977

Paz-Garcia, J M; Dykstra, J E; Biesheuvel, P M; Hamelers, H V M

2015-03-15

138

Differences in oxygen uptake but equivalent energy expenditure between a brief bout of cycling and running  

PubMed Central

Background We examined aerobic and anaerobic exercise energy expenditure and excess post-exercise oxygen consumption (EPOC) between a 250 Watt, 1-minute bout of cycling and uphill treadmill running. Methods Fourteen active to well-trained subjects volunteered for the investigation (VO2 max: 57.0 ± 12.9 ml·kg·min-1 cycle; 59.3 ± 13.7 ml·kg·min-1 run; p = 0.44). Anaerobic energy expenditure was estimated from ?blood lactate. Statistical analysis was completed using a paired t-test (mean ± SD). Results Perceived exertion did not differ between exercise bouts (14.0 ± 2.3 cycle; 13.2 ± 2.1 run; p = 0.29). Exercise oxygen uptake was significantly greater for running (41.4 ± 6.9 kJ) compared to cycling (31.7 ± 7.7 kJ) (p = 0.0001). EPOC was not different between cycling and running (p = 0.21) so that exercise oxygen uptake + EPOC was greater for running (103.0 ± 13.5 kJ) as compared to cycling (85.4 ± 20.2 kJ; p = 0.008). Anaerobic energy expenditure was significantly greater for cycling (32.7 ± 8.9 kJ) versus running (22.5 ± 11.1 kJ) (p = 0.009). Aerobic + anaerobic exercise energy expenditure (cycle 64.3 ± 12.2 kJ; run 63.9 ± 10.1 kJ) (p = 0.90) and total energy expenditure (including EPOC; cycle 118.0 ± 21.8 kJ; run 125.4 ± 19.1 kJ; p = 0.36) were similar for cycling and running. Conclusion Oxygen-only measures reveal discrepancy in energy expenditure between cycling and uphill running. Measurements of exercise oxygen uptake, ?blood lactate and a modified EPOC promote the hypothesis of a similarity in exercise and total energy expenditure between 1-minute work-equivalent bouts of cycling and uphill running. PMID:16390548

Scott, Christopher B; Littlefield, Nathanael D; Chason, Jeffrey D; Bunker, Michael P; Asselin, Elizabeth M

2006-01-01

139

The U.S. Department of Energy`s integrated gasification combined cycle research, development and demonstration program  

SciTech Connect

Historically, coal has played a major role as a fuel source for power generation both domestically and abroad. Despite increasingly stringent environmental constraints and affordable natural gas, coal will remain one of the primary fuels for producing electricity. This is due to its abundance throughout the world, low price, ease of transport an export, decreasing capital cost for coal-based systems, and the need to maintain fuel diversity. Recognizing the role coal will continue to play, the US Department of Energy (DOE) is working in partnership with industry to develop ways to use this abundant fuel resource in a manner that is more economical, more efficient and environmentally superior to conventional means to burn coal. The most promising of these technologies is integrated gasification combined cycle (IGCC) systems. Although IGCC systems offer many advantages, there are still several hurdles that must be overcome before the technology achieves widespread commercial acceptance. The major hurdles to commercialization include reducing capital and operating costs, reducing technical risk, demonstrating environmental and technical performance at commercial scale, and demonstrating system reliability and operability. Overcoming these hurdles, as well as continued progress in improving system efficiency, are the goals of the DOE IGCC research, development and demonstrate (RD and D) program. This paper provides an overview of this integrated RD and D program and describes fundamental areas of technology development, key research projects and their related demonstration scale activities.

Brdar, R.D.; Cicero, D.C.

1996-07-01

140

Simplified thermoeconomic approach to cost allocation in acombined cycle cogeneration and district energy system  

E-print Network

Conservation of Cost Principle For any district energy system ? non-profit or for-profit ? the total cost of the delivered energy must equal or exceed the cost of the primary energy plus overhead cost. For example, if $100 of natural gas and $50...

Fleming, Jason Graham

1997-01-01

141

A Feasibility Study of CO2-Based Rankine Cycle Powered by Solar Energy  

NASA Astrophysics Data System (ADS)

An experiment study was carried out in order to investigate feasibility of CO2-based Rankine cycle powered by solar energy. The proposed cycle is to achieve a cogeneration of heat and power, which consists of evacuated solar tube collectors, power generating turbine, heat recovery system, and feed pump. The Rankine cycle of the system utilizes solar collectors to convert CO2 into high-temperature supercritical state, used to drive a turbine and produce electrical power. The cycle also recovers thermal energy, which can be used for absorption refrigerator, air conditioning, hot water supply so on for a building. A set of experimental set-up was constructed to investigate the performance of the CO2-based Rankine cycle. The results show the cycle can achieve production of heat and power with reasonable thermodynamics efficiency and has a great potential of the application of the CO2-based Rankine cycle powered by solar energy. In addition, some research interests related to the present study will also be discussed in this paper.

Zhang, Xin-Rong; Yamaguchi, Hiroshi; Fujima, Katsumi; Enomoto, Masatoshi; Sawada, Noboru

142

Gentle STEM: ADF imaging and EELS at low primary energies$ Ondrej L. Krivanek a,n  

E-print Network

Gentle STEM: ADF imaging and EELS at low primary energies$ Ondrej L. Krivanek a,n , Niklas Dellby, Parks Road, Oxford OX1 3PH, UK a r t i c l e i n f o Keywords: STEM ADF EELS Aberration correction electron dose. Elemental analysis by electron energy loss spectroscopy (EELS) is then usefully supplemented

Pennycook, Steve

143

An Experimental Project on Energy Education for Rural Women, Primary School Children and Teachers Report.  

ERIC Educational Resources Information Center

One of the University of Baroda's (India) Rural/Tribal Block Placement Program's major aims during the year 1988-89 was to develop energy consciousness in women, primary school children and teachers. An experimental project was designed for a rural Indian village. The objectives were to obtain information on rural energy resources; assess the role…

Pathak, Yogini; Mankodi, Hina

144

Promoting Knowledge Creation Discourse in an Asian Primary Five Classroom: Results from an Inquiry into Life Cycles  

ERIC Educational Resources Information Center

The phrase "knowledge creation" refers to the practices by which a community advances its collective knowledge. Experience with a model of knowledge creation could help students to learn about the nature of science. This research examined how much progress a teacher and 16 Primary Five (Grade 4) students in the International Baccalaureate Primary…

van Aalst, Jan; Truong, Mya Sioux

2011-01-01

145

Energy dependent pitch angle distributions of auroral primary electrons  

NASA Astrophysics Data System (ADS)

Double-layer/parallel-electric field accelerations and the subsequent electron-beam plasma interactions involving Cerenkov and anomalous cyclotron resonances are considered. It is found that these phenomena yield pitch angle distributions as noted from rocket and satellite studies. Although the electron acceleration by weak parallel electric fields forming a runaway electron tail is limited to a critical parallel energy determined by the anomalous cyclotron resonance, such a limitation does not occur with acceleration by a localized parallel electric field such as that in a double layer.

Singh, N.

1988-02-01

146

Life cycle assessment of biofuels: Energy and greenhouse gas balances  

Microsoft Academic Search

The promotion of biofuels as energy for transportation in the industrialized countries is mainly driven by the perspective of oil depletion, the concerns about energy security and global warming. However due to sustainability constraints, biofuels will replace only 10 to 15% of fossil liquid fuels in the transport sector. Several governments have defined a minimum target of GHG emissions reduction

E. Gnansounou; A. Dauriat; J. Villegas; L. Panichelli

2009-01-01

147

Life cycle energy assessment of Australian secondary schools  

Microsoft Academic Search

The Australian Department of Commerce builds many secondary schools in New South Wales every year, and the impact of energy consumption for such a type of construction has rarely been done before in Australia. Although there is a particular responsibility to ensure that public-owned projects contribute to the future well-being of the natural environment, environmental performance and energy efficiency of

Grace K. C. Ding

2007-01-01

148

Sustainable Energy Solutions Task 3.0:Life-Cycle Database for Wind Energy Systems  

SciTech Connect

EXECUTIVE SUMMARY The benefits of wind energy had previously been captured in the literature at an overview level with relatively low transparency or ability to understand the basis for that information. This has limited improvement and decision-making to larger questions such as wind versus other electrical sources (such as coal-fired plants). This research project has established a substantially different approach which is to add modular, high granularity life cycle inventory (lci) information that can be used by a wide range of decision-makers, seeking environmental improvement. Results from this project have expanded the understanding and evaluation of the underlying factors that can improve both manufacturing processes and specifically wind generators. The use of life cycle inventory techniques has provided a uniform framework to understand and compare the full range of environmental improvement in manufacturing, hence the concept of green manufacturing. In this project, the focus is on 1. the manufacturing steps that transform materials and chemicals into functioning products 2. the supply chain and end-of-life influences of materials and chemicals used in industry Results have been applied to wind generators, but also impact the larger U.S. product manufacturing base. For chemicals and materials, this project has provided a standard format for each lci that contains an overview and description, a process flow diagram, detailed mass balances, detailed energy of unit processes, and an executive summary. This is suitable for integration into other life cycle databases (such as that at NREL), so that broad use can be achieved. The use of representative processes allows unrestricted use of project results. With the framework refined in this project, information gathering was initiated for chemicals and materials in wind generation. Since manufacturing is one of the most significant parts of the environmental domain for wind generation improvement, this project research has developed a fundamental approach. The emphasis was place on individual unit processes as an organizing framework to understand the life cycle of manufactured products. The rearrangement of unit processes provides an efficient and versatile means of understanding improved manufactured products such as wind generators. The taxonomy and structure of unit process lci were developed in this project. A series of ten unit process lci were developed to sample the major segments of the manufacturing unit process taxonomy. Technical and economic effectiveness has been a focus of the project research in Task three. The use of repeatable modules for the organization of information on environmental improvement has a long term impact. The information developed can be used and reused in a variety of manufacturing plants and for a range of wind generator sizes and designs. Such a modular approach will lower the cost of life cycle analysis, that is often asked questions of carbon footprint, environmental impact, and sustainability. The use of a website for dissemination, linked to NREL, adds to the economic benefit as more users have access to the lci information. Benefit to the public has been achieved by a well-attended WSU conference, as well as presentations for the Kansas Wind Energy Commission. Attendees represented public interests, land owners, wind farm developers, those interested in green jobs, and industry. Another benefit to the public is the start of information flow from manufacturers that can inform individuals about products.

Janet M Twomey, PhD

2010-04-30

149

Fast-cycling superconducting synchrotrons and possible path to the future of US experimental high-energy particle physics  

SciTech Connect

The authors outline primary physics motivation, present proposed new arrangement for Fermilab accelerator complex, and then discuss possible long-range application of fast-cycling superconducting synchrotrons at Fermilab.

Piekarz, Henryk; /Fermilab

2008-02-01

150

Comparison Between Air and Helium for Use as Working Fluids in the Energy-Conversion Cycle of the MPBR  

E-print Network

A comparison between air and helium for use as working fluids in the energy-conversion cycle of the MPBR is presented. To date, helium has been selected in the MPBR indirect-cycle working reference design. Air open- and ...

Galen, T. A.

151

Life Cycle Assessment of fossil energy use and greenhouse gas emissions in Chinese pear production  

Microsoft Academic Search

A Life Cycle Assessment (LCA) was performed to analyze environmental consequences of different pear production chains in terms of fossil energy use and greenhouse gas (GHG) emission in China. The assessment identified hotspots that contributed significantly to the environmental impacts of pear production from the cradle to the point of sale. The results showed that GHG emissions and fossil energy

Yuexian Liu; Vibeke Langer; Henning Høgh-Jensen; Henrik Egelyng

2010-01-01

152

A System Dynamics Study of Carbon Cycling and Electricity Generation from Energy Crops  

E-print Network

1 A System Dynamics Study of Carbon Cycling and Electricity Generation from Energy Crops Hilary. This paper describes a system dynamics model of the carbon impacts from a dedicated energy crop. The work relies on another carbon accounting model, GORCAM, which uses spreadsheet modeling to investigate various

Ford, Andrew

153

Energy performance of the economizer cycle under three climatic conditions in Saudi Arabia  

Microsoft Academic Search

Heating, ventilating and air conditioning (HVAC) systems are the main consumer of energy in buildings. A considerable amount of energy can be saved if the HVAC system is properly designed, operated and controlled. In all-air HVAC systems using an economizer cycle (which allows the use of outdoor air to condition interior spaces when it is at an appropriate temperature) can

I. M. Budaiwi

2001-01-01

154

Unconventional working fluids in organic Rankine-cycles for waste energy recovery systems  

Microsoft Academic Search

This paper investigates the thermodynamic and physical properties of some unconventional fluids for use in organic Rankine-cycles supplied by waste energy sources. Energy requirement and recovery system performances are analyzed using realistic design operating conditions. Thermodynamic efficiencies and other useful results have been calculated by varying some recovery system operating parameters at various reference temperatures. With reference to proposed application,

V. Maizza; A. Maizza

2001-01-01

155

Material and energy recovery in integrated waste management systems. An evaluation based on life cycle assessment  

SciTech Connect

This paper reports the environmental results, integrated with those arising from mass and energy balances, of a research project on the comparative analysis of strategies for material and energy recovery from waste, funded by the Italian Ministry of Education, University and Research. The project, involving the cooperation of five University research groups, was devoted to the optimisation of material and energy recovery activities within integrated municipal solid waste (MSW) management systems. Four scenarios of separate collection (overall value of 35%, 50% without the collection of food waste, 50% including the collection of food waste, 65%) were defined for the implementation of energetic, environmental and economic balances. Two sizes of integrated MSW management system (IWMS) were considered: a metropolitan area, with a gross MSW production of 750,000 t/year and an average province, with a gross MSW production of 150,000 t/year. The environmental analysis was conducted using Life Cycle Assessment methodology (LCA), for both material and energy recovery activities. In order to avoid allocation we have used the technique of the expansion of the system boundaries. This means taking into consideration the impact on the environment related to the waste management activities in comparison with the avoided impacts related to the saving of raw materials and primary energy. Under the hypotheses of the study, both for the large and for the small IWMS, the energetic and environmental benefits are higher than the energetic and environmental impacts for all the scenarios analysed in terms of all the indicators considered: the scenario with 50% separate collection in a drop-off scheme excluding food waste shows the most promising perspectives, mainly arising from the highest collection (and recycling) of all the packaging materials, which is the activity giving the biggest energetic and environmental benefits. Main conclusions of the study in the general field of the assessment of the environmental performance of any integrated waste management scheme address the importance of properly defining, beyond the design value assumed for the separate collection as a whole, also the yields of each material recovered; particular significance is finally related to the amount of residues deriving from material recovery activities, resulting on average in the order of 20% of the collected materials.

Giugliano, Michele; Cernuschi, Stefano [Politecnico di Milano - DIIAR, Environmental Section, P.zza Leonardo da Vinci, 32, 20133 Milano (Italy); Grosso, Mario, E-mail: mario.grosso@polimi.it [Politecnico di Milano - DIIAR, Environmental Section, P.zza Leonardo da Vinci, 32, 20133 Milano (Italy); Rigamonti, Lucia [Politecnico di Milano - DIIAR, Environmental Section, P.zza Leonardo da Vinci, 32, 20133 Milano (Italy)

2011-09-15

156

Carbon Cycles  

NSDL National Science Digital Library

Students are introduced to the concept of energy cycles by learning about the carbon cycle. They learn how carbon atoms travel through the geological (ancient) carbon cycle and the biological/physical carbon cycle. They consider how human activities disturb the carbon cycle by emitting carbon dioxide into the atmosphere. They discuss how engineers and scientists are working to reduce carbon dioxide emissions. Lastly, students consider how they can help the world through simple energy conservation measures.

Integrated Teaching and Learning Program,

157

Improvements in Life Cycle Energy Efficiency and Greenhouse Gas Emissions of Corn-Ethanol  

Microsoft Academic Search

SummaryCorn-ethanol production is expanding rapidly with the adoption of improved technologies to increase energy efficiency and profitability in crop production, ethanol conversion, and coproduct use. Life cycle assessment can evaluate the impact of these changes on environmental performance metrics. To this end, we analyzed the life cycles of corn-ethanol systems accounting for the majority of U.S. capacity to estimate greenhouse

Adam J. Liska; Haishun S. Yang; Virgil R. Bremer; Terry J. Klopfenstein; Daniel T. Walters; Galen E. Erickson; Kenneth G. Cassman

2009-01-01

158

Energy Storage: Breakthrough in Battery Technologies (Carbon Cycle 2.0)  

SciTech Connect

Nitash Balsara speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 2, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

Balsara, Nitash

2010-02-04

159

Energy Storage: Breakthrough in Battery Technologies (Carbon Cycle 2.0)  

ScienceCinema

Nitash Balsara speaks at the Carbon Cycle 2.0 kick-off symposium Feb. 2, 2010. We emit more carbon into the atmosphere than natural processes are able to remove - an imbalance with negative consequences. Carbon Cycle 2.0 is a Berkeley Lab initiative to provide the science needed to restore this balance by integrating the Labs diverse research activities and delivering creative solutions toward a carbon-neutral energy future. http://carboncycle2.lbl.gov/

Balsara, Nitash

2011-06-03

160

Conceptual Design for Lower-Energy Primary Aluminum  

NASA Astrophysics Data System (ADS)

Operating parameters have been identified such that slag melts typical of other carbothermic aluminum processes are thermodynamically unstable. This facilitates the direct reaction of carbon in carbon-saturated aluminum with alumina under dispersed-contact high-intensity conditions. A conceptual design for one million tonnes per annum (1 Mtpa) aluminum production from Bayer alumina is developed. Freestanding graphite reactors and an ancillary plant encapsulated by inert gas are totally unconstrained within refractory-lined shells. Electrical conductive heating and melt circulation in closed loops, employing a 10 vol pct dispersion of fine carbon particles in aluminum (slurry), transports sensible heat to a single pressurized metal-producing reactor (MPR) to satisfy the endothermicity. In the proposed plant, an MPR at 0.28 MPa (2.8 bar) and 2433 K (2160 °C) with a hearth 2-m-wide × 190-m-long leads the melt via a barometric leg back to essentially atmospheric pressure, for further in-line processing. The impeller-stirred assimilation of fine carbon particles is followed by multistage gas-lift pumping to provide a 5.4-m total head, as required by two parallel straight-line melt-conductive heaters 1 m in diameter × 226 m in length. Overall energy-consumption figures 28.7 pct lower than today’s more recently installed Hall Heroult electrolytic plants are predicted, with 51.3 pct less purchased electricity, supplemented with 1.10 times the stoichiometric elemental carbon.

Warner, N. A.

2008-04-01

161

Experimental studies of a steam jet refrigeration cycle: Effect of the primary nozzle geometries to system performance  

Microsoft Academic Search

This paper describes an experimental investigation of a steam jet refrigeration. A 1kW cooling capacity experimental refrigerator was constructed and tested. The system was tested with various operating temperatures and various primary nozzles. The boiler saturation temperature ranked from 110 to 150°C. The evaporator temperature was fixed at 7.5°C. Eight primary nozzles with difference geometries were used. Six nozzles have

Natthawut Ruangtrakoon; Satha Aphornratana; Thanarath Sriveerakul

2011-01-01

162

Forecasting the primary energy demand in Turkey and analysis of cyclic patterns  

Microsoft Academic Search

The planning and estimation of future energy demand via modern statistical methods have been officially used in Turkey since 1984. However, almost all previous forecasts proved significantly higher than actual observations because of several reasons discussed here. The cycle analysis, which is a semi-statistical technique that makes use of any cyclicity in the historical data of annual additional amounts of

Volkan ?. Ediger; Hüseyin Tatl?dil

2002-01-01

163

Primary energy spectrum of cosmic rays obtained by arrival time spread of particles in EAS  

NASA Astrophysics Data System (ADS)

The Large Area Air Shower (LAAS) group has been performing a network observation of extensive air showers (EAS) by using compact arrays. According to J. Linsley, the primary energy of EAS can be estimated from the spread of the arrival times of EAS particles, even with a small array. A shift register system for clocking the arrival times was installed in an array (OUS1) which is located in Okayama University of Science. Analyzing the OUS1 data, we obtained the primary energies of large air showers.

Okita, M.; Wada, T.; Yamashita, Y.; Okei, K.; Morita, T.; Liang, S.; Takahashi, N.; Iyono, A.; Matsumoto, H.; Noda, C.; Masuda, M.; Yamamoto, I.; Kohata, M.; Ochi, N.; Nakatsuka, T.; Tsuji, S.

2008-01-01

164

Assessment of energy performance in the life-cycle of biogas production  

Microsoft Academic Search

Energy balances are analysed from a life-cycle perspective for biogas systems based on 8 different raw materials. The analysis is based on published data and relates to Swedish conditions. The results show that the energy input into biogas systems (i.e. large-scale biogas plants) overall corresponds to 20–40% (on average approximately 30%) of the energy content in the biogas produced. The

Maria Berglund; Pål Börjesson

2006-01-01

165

Cycle Evaluations of Reversible Chemical Reactions for Solar Thermochemical Energy Storage in Support of Concentrating Solar Power Generation Systems  

SciTech Connect

The production and storage of thermochemical energy is a possible route to increase capacity factors and reduce the Levelized Cost of Electricity from concentrated solar power generation systems. In this paper, we present the results of cycle evaluations for various thermochemical cycles, including a well-documented ammonia closed-cycle along with open- and closed-cycle versions of hydrocarbon chemical reactions. Among the available reversible hydrocarbon chemical reactions, catalytic reforming-methanation cycles are considered; specifically, various methane-steam reforming cycles are compared to the ammonia cycle. In some cases, the production of an intermediate chemical, methanol, is also included with some benefit being realized. The best case, based on overall power generation efficiency and overall plant capacity factor, was found to be an open cycle including methane-steam reforming, using concentrated solar energy to increase the chemical energy content of the reacting stream, followed by combustion to generate heat for the heat engine.

Krishnan, Shankar; Palo, Daniel R.; Wegeng, Robert S.

2010-07-25

166

The potential of solar energy use in desiccant cooling cycles  

Microsoft Academic Search

The use of heat produced by solar thermal collectors is an interesting option for thermal driven air conditioning processes. A thermal driven cooling technique which fits well to non-tracking solar collectors is the desiccant cooling technique. Recently several projects have been carried out which focus on the connection of desiccant cooling systems with solar thermal energy for regeneration of the

H-M Henning; T Erpenbeck; C Hindenburg; I. S Santamaria

2001-01-01

167

Reducing Life Cycle Cost By Energy Saving in Pump Systems  

E-print Network

Pumps consume about 15% of all electricity generated world wide. In the USA alone this accounts for over 130TWh per annum. A saving of only 1% would amount to $80 million in electricity cost. The importance of energy saving, in pump systems...

Bower, J. R.

168

Energy and nutrient cycling in pig production systems  

NASA Astrophysics Data System (ADS)

United States pig production is centered in Iowa and is a major influence on the economic and ecological condition of that community. A pig production system includes buildings, equipment, production of feed ingredients, feed processing, and nutrient management. Although feed is the largest single input into a pig production system, nearly 30% of the non-solar energy use of a conventional--mechanically ventilated buildings with liquid manure handling--pig production system is associated with constructing and operating the pig facility. Using bedded hoop barns for gestating sows and grow-finish pigs reduces construction resource use and construction costs of pig production systems. The hoop based systems also requires approximately 40% less non-solar energy to operate as the conventional system although hoop barn-based systems may require more feed. The total non-solar energy input associated with one 136 kg pig produced in a conventional farrow-to-finish system in Iowa and fed a typical corn-soybean meal diet that includes synthetic lysine and exogenous phytase is 967.9 MJ. Consuming the non-solar energy results in emissions of 79.8 kg CO2 equivalents. Alternatively producing the same pig in a system using bedded hoop barns for gestating sows and grow-finish pigs requires 939.8 MJ/pig and results in emission of 70.2 kg CO2 equivalents, a reduction of 3 and 12% respectively. Hoop barn-based swine production systems can be managed to use similar or less resources than conventional confinement systems. As we strive to optimally allocate non-solar energy reserves and limited resources, support for examining and improving alternative systems is warranted.

Lammers, Peter J.

169

From Cycling Between Coupled Reactions to the Cross-Bridge Cycle: Mechanical Power Output as an Integral Part of Energy Metabolism  

PubMed Central

ATP delivery and its usage are achieved by cycling of respective intermediates through interconnected coupled reactions. At steady state, cycling between coupled reactions always occurs at zero resistance of the whole cycle without dissipation of free energy. The cross-bridge cycle can also be described by a system of coupled reactions: one energising reaction, which energises myosin heads by coupled ATP splitting, and one de-energising reaction, which transduces free energy from myosin heads to coupled actin movement. The whole cycle of myosin heads via cross-bridge formation and dissociation proceeds at zero resistance. Dissipation of free energy from coupled reactions occurs whenever the input potential overcomes the counteracting output potential. In addition, dissipation is produced by uncoupling. This is brought about by a load dependent shortening of the cross-bridge stroke to zero, which allows isometric force generation without mechanical power output. The occurrence of maximal efficiency is caused by uncoupling. Under coupled conditions, Hill’s equation (velocity as a function of load) is fulfilled. In addition, force and shortening velocity both depend on [Ca2+]. Muscular fatigue is triggered when ATP consumption overcomes ATP delivery. As a result, the substrate of the cycle, [MgATP2?], is reduced. This leads to a switch off of cycling and ATP consumption, so that a recovery of [ATP] is possible. In this way a potentially harmful, persistent low energy state of the cell can be avoided. PMID:24957757

Diederichs, Frank

2012-01-01

170

Life cycle assessment of biofuels: energy and greenhouse gas balances.  

PubMed

The promotion of biofuels as energy for transportation in the industrialized countries is mainly driven by the perspective of oil depletion, the concerns about energy security and global warming. However due to sustainability constraints, biofuels will replace only 10 to 15% of fossil liquid fuels in the transport sector. Several governments have defined a minimum target of GHG emissions reduction for those biofuels that will be eligible to public incentives, for example a 35% emissions reduction in case of biofuels in Members States of the European Union. This article points out the significant biases in estimating GHG balances of biofuels stemming from modelling choices about system definition and boundaries, functional unit, reference systems and allocation methods. The extent to which these choices influence the results is investigated. After performing a comparison and constructive criticism of various modelling choices, the LCA of wheat-to-bioethanol is used as an illustrative case where bioethanol is blended with gasoline at various percentages (E5, E10 and E85). The performance of these substitution options is evaluated as well. The results show a large difference in the reduction of the GHG emissions with a high sensitivity to the following factors: the method used to allocate the impacts between the co-products, the type of reference systems, the choice of the functional unit and the type of blend. The authors come out with some recommendations for basing the estimation of energy and GHG balances of biofuels on principles such as transparency, consistency and accuracy. PMID:19553106

Gnansounou, E; Dauriat, A; Villegas, J; Panichelli, L

2009-11-01

171

Economics, environment, and energy life cycle assessment of automobiles fueled by bio-ethanol blends in China  

Microsoft Academic Search

This study examines the life cycle economics, environment impacts, and energy consumptions of Chinese automobiles fueled by bio-ethanol blends, utilizing life cycle assessment (LCA) techniques, and puts forward C, Env, En, EEE indicators to assess the economics, combined environmental impacts, energy consumption, and the balance of the three, as a means to evaluate whether the energy utilization efficiency and the

Zhiyuan Hu; Gengqiang Pu; Fang Fang; Chengtao Wang

2004-01-01

172

Evaluation of the effective energy of primary and transmmitted workload weighted X-ray spectra  

NASA Astrophysics Data System (ADS)

Current methods for X-ray shielding evaluation for imaging facilities do not take into account the effective energy of the radiation impinging on primary barrier. In addition, the X-ray beam attenuation through the patient is not considered in radiation shielding. The proposed models do not deal with the hardening of the spectra between the primary and transmitted beams. Therefore, the present work proposes the evaluation of X-ray spectra transmitted by an adult patient (anthropomorphic phantom) and a shielding barrier weighted by typical workload distributions. A set of primary spectra produced by a voltage range from 60 to 140 kV was measured with a CdTe spectrometer system. A second set of X-ray spectra transmitted through a 15 mm thickness barite mortar plate was also measured employing the same beam quality and voltage range. The air-kerma was simultaneously measured using an ionization chamber. The primary and transmitted experimental X-ray spectra were weighted by a typical chest examination workload distribution. The resulting weighted spectra represent the superposition of the radiation beams typically used in chest examinations. The effective energy of primary weighted spectra was estimated in 42.4 keV and the effective energy of the corresponding transmitted spectra was estimated in 64.7 keV.

Santos, J. C.; Costa, P. R.

2014-02-01

173

Life-cycle energy efficiency and environmental impacts of bioethanol production from sweet potato.  

PubMed

Life-cycle assessment (LCA) was used to evaluate the energy efficiency and environmental impacts of sweet potato-based bioethanol production. The scope covered all stages in the life cycle of bioethanol production, including the cultivation and treatment, transport, as well as bioethanol conversion of sweet potato. Results show that the net energy ratio of sweet potato-based bioethanol is 1.48 and the net energy gain is 6.55 MJ/L. Eutrophication is identified as the most significant environmental impact category, followed by acidification, global warming, human toxicity, and photochemical oxidation. Sensitivity analysis reveals that steam consumption during bioethanol conversion exerts the most effect on the results, followed by sweet potato yields and fertilizers input. It is suggested that substituting coal with cleaner energy for steam generation in bioethanol conversion stage and promotion of better management practices in sweet potato cultivation stage could lead to a significant improvement of energy and environmental performance. PMID:23434804

Wang, Mingxin; Shi, Yu; Xia, Xunfeng; Li, Dinglong; Chen, Qun

2013-04-01

174

The energy spectrum of primary cosmic rays estimated by using the arrival time spread of air shower particles  

Microsoft Academic Search

The primary energy of cosmic rays in the energy region above 1016 eV has been studied with the use of a compact extensive air shower (EAS) array which consists of 8 scintillation counters in 200m2 area. We report on the simulation results for estimating the primary energy and its spectrum by using Linsley's method, and on the improvement of the

H. Matsumoto; A. Iyono; I. Yamamoto; M. Kohata; K. Okei; S. Tsuji; T. Nakatsuka; N. Ochi

2009-01-01

175

Body Parts, the Water Cycle, Plants, and Dolphins: Adventures in Primary-Grade Whole-Class Composing  

ERIC Educational Resources Information Center

This article describes the author's personal experiences leading primary grades in whole-class composing. Together they created songs inspired by topics the students were exploring in their homeroom classes. The author systematically describes the songwriting process they employed, identifying specific challenges encountered along the way. The…

Bolden, Benjamin

2009-01-01

176

Primary energy spectrum of cosmic rays obtained by arrival time spread of particles in EAS  

Microsoft Academic Search

The Large Area Air Shower (LAAS) group has been performing a network observation of extensive air showers (EAS) by using compact arrays. According to J. Linsley, the primary energy of EAS can be estimated from the spread of the arrival times of EAS particles, even with a small array. A shift register system for clocking the arrival times was installed

M. Okita; T. Wada; Y. Yamashita; K. Okei; T. Morita; S. Liang; N. Takahashi; A. Iyono; H. Matsumoto; C. Noda; M. Masuda; I. Yamamoto; M. Kohata; N. Ochi; T. Nakatsuka; S. Tsuji

2008-01-01

177

Hydrodynamics of a new concept of primary containment by energy absorption  

NASA Technical Reports Server (NTRS)

Fluid dynamical analysis for idealized reactors system with spherical symmetry determines the effect which the destructive component of a nuclear accident produces on primary containment structures. Steel strands surrounding the reactor cavity in the biological shield exhibit plastic deformation to achieve the energy absorption.

Fistedis, S. H.; Sorensen, H. C.

1969-01-01

178

ENERGY SPECTRA OF PRIMARY AND SECONDARY COSMIC-RAY NUCLEI MEASURED WITH TRACER  

SciTech Connect

The Transition Radiation Array for Cosmic Energetic Radiation (TRACER) cosmic-ray detector, first flown on long-duration balloon (LDB) in 2003 for observations of the major primary cosmic-ray nuclei from oxygen (Z = 8) to iron (Z = 26), has been upgraded to also measure the energies of the lighter nuclei, including the secondary species boron (Z = 5). The instrument was used in another LDB flight in 2006. The properties and performance of the modified detector system are described, and the analysis of the data from the 2006 flight is discussed. The energy spectra of the primary nuclei carbon (Z = 6), oxygen, and iron over the range from 1 GeV amu{sup -1} to 2 TeV amu{sup -1} are reported. The data for oxygen and iron are found to be in good agreement with the results of the previous TRACER flight. The measurement of the energy spectrum of boron also extends into the TeV amu{sup -1} region. The relative abundances of the primary nuclei, such as carbon, oxygen, and iron, above {approx}10 GeV amu{sup -1} are independent of energy, while the boron abundance, i.e., the B/C abundance ratio, decreases with energy as expected. However, there is an indication that the previously reported E {sup -0.6} dependence of the B/C ratio does not continue to the highest energies.

Obermeier, A.; Ave, M.; Boyle, P.; Hoeppner, Ch.; Mueller, D. [Enrico Fermi Institute, University of Chicago, Chicago, IL 60637 (United States); Hoerandel, J., E-mail: a.obermeier@astro.ru.nl [Department of Astrophysics, Radboud University Nijmegen, 6525 HP Nijmegen (Netherlands)

2011-11-20

179

Differences in expression of proliferation-associated genes and RANKL across the menstrual cycle in estrogen receptor-positive primary breast cancer.  

PubMed

The purpose of this study is to determine if there are differences in the expression of estrogen-regulated genes (ERGs), proliferation-associated genes and the progesterone effector RANKL, in premenopausal ER+ breast cancer as a result of the major changes in hormone levels that occur through the menstrual cycle. Primary ER+ tumours from 174 patients were assigned to one of three menstrual cycle windows: W1 (days 27-35 + 1-6), W2 (days 7-16) and W3 (days 17-26). RNA expression of 42 genes, including 24 putative genes associated with plasma E2 levels, seven proliferation genes and RANKL was measured. Expression of PGR, TFF1, GREB1 and PDZK1 followed the previously reported pattern: a higher level in W2 compared to W1 while W3 had an intermediate value, mirroring changes in plasma estradiol. Of the other 20 ERGs, four (RUNX1, AGR2, SERPINA3 and SERPINA5) showed significant differences (p = 0.009-0.049) in expression across the menstrual cycle. The expression of six of seven proliferation-associated genes varied across the cycle but differently from the ERGs, being 20-35 % lower in W3 compared to W1 and W2 (p = 0.004-0.031). Expression of RANKL was 2.5 to 3-fold highest in W3 (p = 0.0001) and negatively correlated to the expression of the proliferation-associated genes (r = -0.37; p < 0.0001). Expression of proliferation-associated genes and RANKL in ER+ breast tumours varies across the menstrual cycle showing a different rhythm to that of ERGs. This may affect the interpretation of gene expression profiles but may be exploitable as an endogenous test of endocrine responsiveness. PMID:25367875

Haynes, Ben P; Viale, Giuseppe; Galimberti, Viviana; Rotmensz, Nicole; Gibelli, Bianca; Smith, Ian E; Dowsett, Mitch

2014-11-01

180

Life cycle assessment as a decision support tool for landfill gas-to energy projects  

Microsoft Academic Search

The greenhouse gas (GHG) emissions from MSW landfill, and control methods to eliminate or minimize these impacts including energy recovery from landfill gas (LFG) of MSW landfill in Thailand have been evaluated. Life Cycle Assessment (LCA) is used as the analytical tool to evaluate the environmental consequences of landfilling holistically. The economic implications of the control methods are also briefly

Wanida Wanichpongpan; Shabbir H. Gheewala

2007-01-01

181

Hydrological consistency using multi-sensor remote sensing data for water and energy cycle studies  

E-print Network

and feedback of land surface and atmospheric processes over large space and time scales. Remote sensingHydrological consistency using multi-sensor remote sensing data for water and energy cycle studies for future remote observation and analysis of the coupled land surface­atmosphere system. © 2007 Elsevier Inc

Pan, Ming

182

Fluid Selection for a Low-Temperature Geothermal Organic Rankine Cycle by Energy and Exergy  

Microsoft Academic Search

A detailed energy and exergy analysis of a low-temperature geothermal organic Rankine cycle is presented, screening the appropriate working fluids for specific heat source conditions. The results have been calculated with pinch point analysis approach for fixed temperature and mass flow rate of the heat source, fixed pinch points in evaporator and condenser and fixed condensing and sink temperatures by

Tao Guo; Huaixin Wang; Shengjun Zhang

2010-01-01

183

Global Energy and Water Cycle Experiment mate models appear to systematically under-predict  

E-print Network

. Regional skew in search of a parent, Water Resources Research 11, 815-826. Milly, P. C. D., J. Betancourt for the Global Energy and Water Cycle Experiment, Geneva. Collateral Damage from the Death of Stationarity Roger article assert that the cause of the death of stationarity is human-caused climate change

Colorado at Boulder, University of

184

Standard mechanical energy analyses do not correlate with muscle work in cycling  

Microsoft Academic Search

The goal of this study was to assess the utility of experimental methods to quantify mechanical energy expenditure (MEE) in human movement. To achieve this goal, a theoretical model of steady-state cycling driven by individual muscle actuators was used to produce two distinct pedal simulations. The simulations yielded the same pedaling rate and power output, but one reduced the MEE

R. R. Neptune; A. J. van den Bogert

1998-01-01

185

Analysis of a Power Cycle Utilizing Low-Grade Solar Energy  

Microsoft Academic Search

This paper has proposed a power system that can provide efficiently using the heat collected by the collector. The system consists a of the Rankine cycle to recover the collected solar energy. It produces power and provides certain amount of domestic hot water. Based on the models, a calculation was done to analysis the performance of the system at the

Jianzhong Song; Xiaosong Zhang

2010-01-01

186

Life-cycle assessment of desalination technologies integrated with energy production systems  

Microsoft Academic Search

Desalination technologies require high energy consumption. As a consequence, the environmental load associated with the operating stage is much higher (more than 90%) than that associated to plant construction, maintenance and final disposal. This paper analyzes the evolution of environmental impact by means of the Life-Cycle Assessment (LCA) technique, caused by the most common commercial desalination technologies used worldwide -

R. G. Raluy; L. Serra; J. Uche; A. Valero

2004-01-01

187

Facility-level energy and greenhouse gas life-cycle assessment of the global nickel industry  

Microsoft Academic Search

Nickel is an integral material to our modern, high-performance technological society. With increasing emphasis being put on energy efficiency and global climate change, it is important for companies to understand in detail the energy use and greenhouse gas implications of their business. The present analysis is a facility-level life-cycle assessment of these twin impacts covering the entire global nickel industry.

Matthew J. Eckelman

2010-01-01

188

Implications of incorporating N cycling and N limitations on primary production in an individual-based dynamic vegetation model  

NASA Astrophysics Data System (ADS)

The LPJ-GUESS dynamic vegetation model uniquely combines an individual- and patch-based representation of vegetation dynamics with ecosystem biogeochemical cycling from regional to global scales. We present an updated version that includes plant and soil N dynamics, analysing the implications of accounting for C-N interactions on predictions and performance of the model. Stand structural dynamics and allometric scaling of tree growth suggested by global databases of forest stand structure and development were well-reproduced by the model in comparison to an earlier multi-model study. Accounting for N cycle dynamics improved the goodness-of-fit for broadleaved forests. N limitation associated with low N mineralisation rates reduces productivity of cold-climate and dry-climate ecosystems relative to mesic temperate and tropical ecosystems. In a model experiment emulating free-air CO2 enrichment (FACE) treatment for forests globally, N-limitation associated with low N mineralisation rates of colder soils reduces CO2-enhancement of NPP for boreal forests, while some temperate and tropical forests exhibit increased NPP enhancement. Under a business-as-usual future climate and emissions scenario, ecosystem C storage globally was projected to increase by c. 10%; additional N requirements to match this increasing ecosystem C were within the high N supply limit estimated on stoichiometric grounds in an earlier study. Our results highlight the importance of accounting for C-N interactions not only in studies of global terrestrial C cycling, but to understand underlying mechanisms on local scales and in different regional contexts.

Smith, B.; Wårlind, D.; Arneth, A.; Hickler, T.; Leadley, P.; Siltberg, J.; Zaehle, S.

2013-11-01

189

Modeling Energy Recovery Using Thermoelectric Conversion Integrated with an Organic Rankine Bottoming Cycle  

SciTech Connect

Hot engine exhaust represents a resource that is often rejected to the environment without further utilization. This resource is most prevalent in the transportation sector, but stationary engine-generator systems also typically do not utilize this resource. Engine exhaust is a source of high grade thermal energy that can potentially be utilized by various approaches to produce electricity or to drive heating and cooling systems. This paper describes a model system that employs thermoelectric conversion as a topping cycle integrated with an organic Rankine bottoming cycle for waste heat utilization. This approach is being developed to fully utilize the thermal energy contained in hot exhaust streams. The model is composed of a high temperature heat exchanger which extracts thermal energy for driving the thermoelectric conversion elements. However, substantial sensible heat remains in the exhaust stream after emerging from the heat exchanger. The model incorporates a closely integrated bottoming cycle to utilize this remaining thermal energy in the exhaust stream. The model has many interacting parameters that define combined system quantities such as overall output power, efficiency, and total energy utilization factors. In addition, the model identifies a maximum power operating point for the system. That is, the model can identify the optimal amount of heat to remove from the exhaust flow to run through the thermoelectric elements. Removing too much or too little heat from the exhaust stream in this stage will reduce overall cycle performance. The model has been developed such that heat exchanger UAh values, thermal resistances, ZT values, and multiple thermoelectric elements can be investigated in the context of system operation. The model also has the ability to simultaneously determine the effect of each cycle design parameter on the performance of the overall system, thus giving the ability to utilize as much waste heat as possible. Key analysis results are presented showing the impact of critical design parameters on power output, system performance and inter-relationships between design parameters in governing performance.

Miller, Erik W.; Hendricks, Terry J.; Peterson, Richard B.

2009-07-01

190

Life-cycle energy and CO2 analysis of stormwater treatment devices.  

PubMed

Environmental impacts associated with the construction, maintenance, and disposal of low-impact stormwater management devices are one aspect that should be considered during decision-making and life-cycle assessment (LCA) is a suitable method for quantifying such impacts. This paper reports a pilot study that employs LCA to compare life-cycle energy requirements and CO2 emissions of two stormwater devices in New Zealand. The two devices are a raingarden servicing an urban feeder road, and a sand filter that could have been installed in its stead. With an assumed life-time of 50 years, the life-cycle energy requirements of the built raingarden were almost 20% less than for the sand filter, while the CO2 emissions were 30% less. Our analysis shows that given the difference between the infiltration rates used in the raingarden design (0.3 m/day) and measured during monitoring (3 m/day) there was potential to make significantly greater life-time savings using a smaller design for the raingarden that would have also met the treatment efficiency expectations. The analysis highlights the significant contribution of transportation-of both materials and staff-and ongoing maintenance to a treatment device's life-cycle energy and CO2 profiles. PMID:18824795

Andrew, R M; Vesely, E-T

2008-01-01

191

Life-cycle energy demand and global warming potential of computational logic.  

PubMed

Computational logic, in the form of semiconductor chips of the complementary metal oxide semiconductor (CMOS) transistor structure, is used in personal computers, wireless devices, IT network infrastructure, and nearly all modem electronics. This study provides a life-cycle energy analysis for CMOS chips over 7 technology generations with the purpose of comparing energy demand and global warming potential (GWP) impacts of the life-cycle stages, examining trends in these impacts over time and evaluating their sensitivity to data uncertainty and changes in production metrics such as yield. A hybrid life-cycle assessment (LCA) model is used. While life-cycle energy and GWP of emissions have increased on the basis of a wafer or die, these impacts have been reducing per unit of computational power. Sensitivity analysis of the model shows that impacts have the highest relative sensitivity to wafer yield, line yield, and die size and largest absolute sensitivity to the use-phase power demand of the chip. PMID:19848138

Boyd, Sarah B; Horvath, Arpad; Dornfeld, David

2009-10-01

192

Optimal energy-harvesting cycles for load-driven dielectric generators in plane strain  

E-print Network

The performances of energy harvesting generators based on dielectric elastomers are investigated. The configuration is of a thin dielectric film coated by stretchable electrodes at both sides. The film is first stretched, then charged and subsequently, afterwards it is released, and finally the charge is harvested at a higher electric potential. The amount of energy extracted by this cycle is bounded by the electric breakdown and the ultimate stretch ratio of the film as well as by structural instabilities due to loss of tension. To identify the optimal cycle that complies with these limits we formulate a constraint optimization problem and solve it with a dedicated solver for two typical classes of elastic dielectrics. As anticipated, we find that the performance of the generator depends critically on the ultimate stretch ratio of the film. However, more surprising is our finding of a universal limit on the dielectric strength of the film beyond which the optimal cycle is independent of this parameter. Thus, we reveal that, regardless of how large the dielectric strength of the material is, there is an upper bound on the amount of harvested energy that depends only on the ultimate stretch ratio. We conclude the work with detailed calculations of the optimal cycles for two commercially available elastic dielectrics.

R. Springhetti; E. Bortot; G. deBotton; M. Gei

2014-03-13

193

Functional unit, technological dynamics, and scaling properties for the life cycle energy of residences.  

PubMed

Prior LCA studies take the operational phase to include all energy use within a residence, implying a functional unit of all household activities, but then exclude related supply chains such as production of food, appliances, and household chemicals. We argue that bounding the functional unit to provision of a climate controlled space better focuses the LCA on the building, rather than activities that occur within a building. The second issue explored in this article is how technological change in the operational phase affects life cycle energy. Heating and cooling equipment is replaced at least several times over the lifetime of a residence; improved efficiency of newer equipment affects life cycle energy use. The third objective is to construct parametric models to describe LCA results for a family of related products. We explore these three issues through a case study of energy use of residences: one-story and two-story detached homes, 1,500-3,500 square feet in area, located in Phoenix, Arizona, built in 2002 and retired in 2051. With a restricted functional unit and accounting for technological progress, approximately 30% of a building's life cycle energy can be attributed to materials and construction, compared to 0.4-11% in previous studies. PMID:22192002

Frijia, Stephane; Guhathakurta, Subhrajit; Williams, Eric

2012-02-01

194

Effects of Fuel Ethanol Use on Fuel-Cycle Energy and Greenhouse Gas Emissions  

SciTech Connect

We estimated the effects on per-vehicle-mile fuel-cycle petroleum use, greenhouse gas (GHG) emissions, and energy use of using ethanol blended with gasoline in a mid-size passenger car, compared with the effects of using gasoline in the same car. Our analysis includes petroleum use, energy use, and emissions associated with chemicals manufacturing, farming of corn and biomass, ethanol production, and ethanol combustion for ethanol; and petroleum use, energy use, and emissions associated with petroleum recovery, petroleum refining, and gasoline combustion for gasoline. For corn-based ethanol, the key factors in determining energy and emissions impacts include energy and chemical usage intensity of corn farming, energy intensity of the ethanol plant, and the method used to estimate energy and emissions credits for co-products of corn ethanol. The key factors in determining the impacts of cellulosic ethanol are energy and chemical usage intensity of biomass farming, ethanol yield per dry ton of biomass, and electricity credits in cellulosic ethanol plants. The results of our fuel-cycle analysis for fuel ethanol are listed below. Note that, in the first half of this summary, the reductions cited are per-vehicle-mile traveled using the specified ethanol/gasoline blend instead of conventional (not reformulated) gasoline. The second half of the summary presents estimated changes per gallon of ethanol used in ethanol blends. GHG emissions are global warming potential (GWP)-weighted, carbon dioxide (CO2)-equivalent emissions of CO2, methane (CH4), and nitrous oxide (N2O).

C. Saricks; D. Santini; M. Wang.

1999-02-08

195

Energy conservation in the primary aluminum and chlor-alkali industries  

SciTech Connect

The primary aluminum and chlor-alkali industries together use nearly 13% of the electrical energy consumed by US industry. As part of its mission to promote energy conservation in basic US industries, the DOE surveys the present technological status of the major electrochemical industries and evaluates promising technological innovations that may lead to reduced energy requirements. This study provides technical and economic analyses in support of a government program of research and development in advanced electrolytic technology. This program is intended to supplement the development efforts directed toward energy savings by private industry. Sections II and III of this report cover aluminum and chlorine production processes only, since these two industries represent over 90% of the electrical energy requirements of all electrolytic industries in the United States. Section IV examines barriers to accelerated research and development by the electrolytic industries, and makes suggestions for government actions to overcome these barriers.

Not Available

1980-10-01

196

National Survey of Energy Balance-related Care among Primary Care Physicians  

Cancer.gov

This survey, one of several physician surveys conducted by the Applied Research Program, is designed to obtain current, nationally representative data on primary care physicians' (PCPs') characteristics, knowledge, attitudes, and practices related to services for diet, physical activity, and weight control. The goal is to develop a national baseline on the use of energy balance risk assessment, counseling and referral services in physician practice and to identify the characteristics of physicians who routinely incorporate these activities in patient care.

197

Shifting primary energy source and NOx emission location with plug-in hybrid vehicles  

Microsoft Academic Search

Plug-in hybrid vehicles (PHEVs) present an interesting technological opportunity for using non-fossil primary energy in light duty passenger vehicles, with the associated potential for reducing air pollutant and greenhouse gas emissions, to the extent that the electric power grid is fed by non-fossil sources. This perspective, accompanying the article by Thompson et al (2011) in this issue, will touch on

Deniz Karman

2011-01-01

198

High-energy half-cycle cutoffs in high harmonic and rescattered electron spectra using waveform-controlled few-cycle infrared pulses  

NASA Astrophysics Data System (ADS)

We developed a few-cycle waveform-controlled light source for infrared pulses at 1.6 ? m that is based on optical chirped-pulse amplification in Bi{{B}3}{{O}6} (BIBO) crystals pumped by Ti:sapphire lasers. Using this source, we observe soft x-ray high harmonics that extend up to a photon energy of ? 320 eV, as well as high-energy photoelectrons up to ? 1 keV. The spectra of the high harmonics and photoelectrons have clear signatures of half-cycle cutoffs that can be used to extract electronic and molecular dynamics on an attosecond time scale.

Geiseler, H.; Ishii, N.; Kaneshima, K.; Kitano, K.; Kanai, T.; Itatani, J.

2014-10-01

199

Energy-containing beverages: reproductive hormones and ovarian function in the BioCycle Study123  

PubMed Central

Background: Energy-containing beverages are widely consumed among premenopausal women, but their association with reproductive hormones is not well understood. Objective: The objective was to assess the association of energy-containing beverages, added sugars, and total fructose intake with reproductive hormones among ovulatory cycles and sporadic anovulation in healthy premenopausal women. Design: Women (n = 259) in the BioCycle Study were followed for up to 2 menstrual cycles; they provided fasting blood specimens during up to 8 visits/cycle and four 24-h dietary recalls/cycle. Results: Women who consumed ?1 cup (1 cup = 237 mL) sweetened soda/d had 16.3% higher estradiol concentrations compared with women who consumed less sweetened soda (86.5 pg/mL compared with 74.4 pg/mL, P = 0.01) after adjustment for age, BMI, race, dietary factors, and physical activity. Similarly elevated estradiol concentrations were found for ?1 cup cola/d and noncola soda intake. Neither artificially sweetened soda nor fruit juice intake ?1 cup/d was significantly associated with reproductive hormones. Added sugar above the average US woman's intake (?73.2 g/d) or above the 66th percentile in total fructose intake (?41.5 g/d) was associated with significantly elevated estradiol but not consistently across all models. No associations were found between beverages, added sugars, or total fructose intake and anovulation after multivariate adjustment. Conclusions: Even at moderate consumption amounts, sweetened soda is associated with elevated follicular estradiol concentrations among premenopausal women but does not appear to affect ovulatory function. Further research into the mechanism driving the association between energy-containing beverages and reproductive hormones, and its potential implications for women's health, is warranted. PMID:23364018

Schliep, Karen C; Mumford, Sunni L; Pollack, Anna Z; Perkins, Neil J; Ye, Aijun; Zhang, Cuilin J; Stanford, Joseph B; Porucznik, Christina A; Hammoud, Ahmad O; Wactawski-Wende, Jean

2013-01-01

200

The energy spectrum of primary cosmic rays estimated by using the arrival time spread of air shower particles  

NASA Astrophysics Data System (ADS)

The primary energy of cosmic rays in the energy region above 10 16 eV has been studied with the use of a compact extensive air shower (EAS) array which consists of 8 scintillation counters in 200m 2 area. We report on the simulation results for estimating the primary energy and its spectrum by using Linsley's method, and on the improvement of the determination accuracy of the primary energy by applying the zenith angle restricted observation of EAS muons with the new array as well as a brief description of the apparatus.

Matsumoto, H.; Iyono, A.; Yamamoto, I.; Kohata, M.; Okei, K.; Tsuji, S.; Nakatsuka, T.; Ochi, N.

2009-12-01

201

Sorting through the many total-energy-cycle pathways possible with early plug-in hybrids.  

SciTech Connect

Using the 'total energy cycle' methodology, we compare U.S. near term (to {approx}2015) alternative pathways for converting energy to light-duty vehicle kilometers of travel (VKT) in plug-in hybrids (PHEVs), hybrids (HEVs), and conventional vehicles (CVs). For PHEVs, we present total energy-per-unit-of-VKT information two ways (1) energy from the grid during charge depletion (CD); (2) energy from stored on-board fossil fuel when charge sustaining (CS). We examine 'incremental sources of supply of liquid fuel such as (a) oil sands from Canada, (b) Fischer-Tropsch diesel via natural gas imported by LNG tanker, and (c) ethanol from cellulosic biomass. We compare such fuel pathways to various possible power converters producing electricity, including (i) new coal boilers, (ii) new integrated, gasified coal combined cycle (IGCC), (iii) existing natural gas fueled combined cycle (NGCC), (iv) existing natural gas combustion turbines, (v) wood-to-electricity, and (vi) wind/solar. We simulate a fuel cell HEV and also consider the possibility of a plug-in hybrid fuel cell vehicle (FCV). For the simulated FCV our results address the merits of converting some fuels to hydrogen to power the fuel cell vs. conversion of those same fuels to electricity to charge the PHEV battery. The investigation is confined to a U.S. compact sized car (i.e. a world passenger car). Where most other studies have focused on emissions (greenhouse gases and conventional air pollutants), this study focuses on identification of the pathway providing the most vehicle kilometers from each of five feedstocks examined. The GREET 1.7 fuel cycle model and the new GREET 2.7 vehicle cycle model were used as the foundation for this study. Total energy, energy by fuel type, total greenhouse gases (GHGs), volatile organic compounds (VOC), carbon monoxide (CO), nitrogen oxides (NO{sub x}), fine particulate (PM2.5) and sulfur oxides (SO{sub x}) values are presented. We also isolate the PHEV emissions contribution from varying kWh storage capability of battery packs in HEVs and PHEVs from {approx}16 to 64 km of charge depleting distance. Sensitivity analysis is conducted with respect to the effect of replacing the battery once during the vehicle's life. The paper includes one appendix that examines several recent studies of interactions of PHEVs with patterns of electric generation and one that provides definitions, acronyms, and fuel consumption estimation steps.

Gaines, L.; Burnham, A.; Rousseau, A.; Santini, D.; Energy Systems

2008-01-01

202

Life cycle comparison of waste-to-energy alternatives for municipal waste treatment in Chilean Patagonia.  

PubMed

The energy system in the Region of Aysén, Chile, is characterized by a strong dependence on fossil fuels, which account for up to 51% of the installed capacity. Although the implementation of waste-to-energy concepts in municipal waste management systems could support the establishment of a more fossil-independent energy system for the region, previous studies have concluded that energy recovery systems are not suitable from an economic perspective in Chile. Therefore, this work intends to evaluate these technical options from an environmental perspective, using life cycle assessment as a tool for a comparative analysis, considering Coyhaique city as a case study. Three technical alternatives were evaluated: (i) landfill gas recovery and flaring without energy recovery; (ii) landfill gas recovery and energy use; and (iii) the implementation of an anaerobic digestion system for the organic waste fraction coupled with energy recovery from the biogas produced. Mass and energy balances of the three analyzed alternatives have been modeled. The comparative LCA considered global warming potential, abiotic depletion and ozone layer depletion as impact categories, as well as required raw energy and produced energy as comparative regional-specific indicators. According to the results, the use of the recovered landfill gas as an energy source can be identified as the most environmentally appropriate solution for Coyhaique, especially when taking into consideration the global impact categories. PMID:23988463

Bezama, Alberto; Douglas, Carla; Méndez, Jacqueline; Szarka, Nóra; Muñoz, Edmundo; Navia, Rodrigo; Schock, Steffen; Konrad, Odorico; Ulloa, Claudia

2013-10-01

203

Air Evaporation closed cycle water recovery technology - Advanced energy saving designs  

NASA Technical Reports Server (NTRS)

The Air Evaporation water recovery system is a visible candidate for Space Station application. A four-man Air Evaporation open cycle system has been successfully demonstrated for waste water recovery in manned chamber tests. The design improvements described in this paper greatly enhance the system operation and energy efficiency of the air evaporation process. A state-of-the-art wick feed design which results in reduced logistics requirements is presented. In addition, several design concepts that incorporate regenerative features to minimize the energy input to the system are discussed. These include a recuperative heat exchanger, a heat pump for energy transfer to the air heater, and solar collectors for evaporative heat. The addition of the energy recovery devices will result in an energy reduction of more than 80 percent over the systems used in earlier manned chamber tests.

Morasko, Gwyndolyn; Putnam, David F.; Bagdigian, Robert

1986-01-01

204

Life cycle water use of energy production and its environmental impacts in China.  

PubMed

The energy sector is a major user of fresh water resources in China. We investigate the life cycle water withdrawals, consumptive water use, and wastewater discharge of China's energy sectors and their water-consumption-related environmental impacts, using a mixed-unit multiregional input-output (MRIO) model and life cycle impact assessment method (LCIA) based on the Eco-indicator 99 framework. Energy production is responsible for 61.4 billion m(3) water withdrawals, 10.8 billion m(3) water consumption, and 5.0 billion m(3) wastewater discharges in China, which are equivalent to 12.3%, 4.1% and 8.3% of the national totals, respectively. The most important feature of the energy-water nexus in China is the significantly uneven spatial distribution of consumptive water use and its corresponding environmental impacts caused by the geological discrepancy among fossil fuel resources, fresh water resources, and energy demand. More than half of energy-related water withdrawals occur in the east and south coastal regions. However, the arid north and northwest regions have much larger water consumption than the water abundant south region, and bear almost all environmental damages caused by consumptive water use. PMID:24125477

Zhang, Chao; Anadon, Laura Diaz

2013-12-17

205

Water loss control using pressure management: life-cycle energy and air emission effects.  

PubMed

Pressure management is one cost-effective and efficient strategy for controlling water distribution losses. This paper evaluates the life-cycle energy use and emissions for pressure management zones in Philadelphia, Pennsylvania, and Halifax, Nova Scotia. It compares water savings using fixed-outlet and flow-modulated pressure control to performance without pressure control, considering the embedded electricity and chemical consumption in the lost water, manufacture of pipe and fittings to repair breaks caused by excess pressure, and pressure management. The resulting energy and emissions savings are significant. The Philadelphia and Halifax utilities both avoid approximately 130 million liters in water losses annually using flow-modulated pressure management. The conserved energy was 780 GJ and 1900 GJ while avoided greenhouse gas emissions were 50 Mg and 170 Mg a year by Philadelphia and Halifax, respectively. The life-cycle financial and environmental performance of pressure management systems compares favorably to the traditional demand management strategy of installing low-flow toilets. The energy savings may also translate to cost-effective greenhouse gas emission reductions depending on the energy mix used, an important advantage in areas where water and energy are constrained and/or expensive and greenhouse gas emissions are regulated as in California, for example. PMID:23869434

Stokes, Jennifer R; Horvath, Arpad; Sturm, Reinhard

2013-10-01

206

Apparatus for realization of rock exploitation method based on thermodynamic cycles utilizing in situ energy source  

Microsoft Academic Search

An apparatus for the realization of a rock-exploitation method based on thermodynamic cycles utilizing an in-situ energy source including a well with a casing sunk at least as far down as a producing horizon, a string of exploitation pipes having at least one opening at the fluid outlet, and means for varying the heat content of the heat-carrying agent in

I. T. Aladiev; V. K. Fardzinov; G. P. Gukov; E. V. Saperov; K. D. Voskresensky

1980-01-01

207

Evaluation of catalyst for closed cycle operation of high energy pulsed CO2 lasers  

NASA Technical Reports Server (NTRS)

Several catalyst materials have been tested for efficiency of converting CO and O2 to CO2 for use in a high energy CO2 laser. The composition of the gas mixtures was monitored by mass spectrometry and gas chromatography. A copper/copper oxide catalyst and a platinum/tin oxide catalyst were used for closed cycle operation of a CO2 laser (0.7 joules/pulse), operating at 10 pulses/sec.

Rogowski, R. S.; Miller, I. M.; Wood, G.; Schryer, D. R.; Hess, R. V.; Upchurch, B. T.

1983-01-01

208

Intercomparison of the seasonal cycle in 200 hPa kinetic energy in AMIP GCM simulations  

SciTech Connect

The 200 hPa kinetic energy is represented by means of the spherical harmonic components for the Atmospheric Model Intercomparison Project (AMIP) simulations, the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis and the European Centre for Medium Range Weather Forecast Reanalysis (ERA). The data used are the monthly mean wind fields from 1979 to 1988. The kinetic energy is decomposed into the divergent (DKE) and rotational (RKE) components and emphasis is placed on examining the former. The two reanalysis data sets show reasonable agreement that is best for the rotational kinetic energy. The largest difference in the divergent kinetic energy occurs during the northern summer. As might be expected, the two analyses are closet in regions where there are sufficient observations such that the effect of the model used in the assimilation cycle are minimized. The observed RKE show only a slight seasonal cycle with a maximum occuring during the northern winter. The DKE, on the other hand, has a very pronounced seasonal cycle with maxima at the solsticial seasons and minima during the equinoctial seasons. The model results show a very large spread in the magnitudes of the RKE and DKE although the models all evince a seasonal variation in phase with that observed. The median values of the seasonal cycle of RKE and DKE for the models are usually superior to those of any individual model. Results are also presented for simulation following the AMIP protocol but using updated versions of the original AMIP entries. In most cases these new integrations show better agreement with the observations.

Boyle, J.S.

1996-10-01

209

Parking infrastructure: energy, emissions, and automobile life-cycle environmental accounting  

NASA Astrophysics Data System (ADS)

The US parking infrastructure is vast and little is known about its scale and environmental impacts. The few parking space inventories that exist are typically regionalized and no known environmental assessment has been performed to determine the energy and emissions from providing this infrastructure. A better understanding of the scale of US parking is necessary to properly value the total costs of automobile travel. Energy and emissions from constructing and maintaining the parking infrastructure should be considered when assessing the total human health and environmental impacts of vehicle travel. We develop five parking space inventory scenarios and from these estimate the range of infrastructure provided in the US to be between 105 million and 2 billion spaces. Using these estimates, a life-cycle environmental inventory is performed to capture the energy consumption and emissions of greenhouse gases, CO, SO2, NOX, VOC (volatile organic compounds), and PM10 (PM: particulate matter) from raw material extraction, transport, asphalt and concrete production, and placement (including direct, indirect, and supply chain processes) of space construction and maintenance. The environmental assessment is then evaluated within the life-cycle performance of sedans, SUVs (sports utility vehicles), and pickups. Depending on the scenario and vehicle type, the inclusion of parking within the overall life-cycle inventory increases energy consumption from 3.1 to 4.8 MJ by 0.1-0.3 MJ and greenhouse gas emissions from 230 to 380 g CO2e by 6-23 g CO2e per passenger kilometer traveled. Life-cycle automobile SO2 and PM10 emissions show some of the largest increases, by as much as 24% and 89% from the baseline inventory. The environmental consequences of providing the parking spaces are discussed as well as the uncertainty in allocating paved area between parking and roadways.

Chester, Mikhail; Horvath, Arpad; Madanat, Samer

2010-07-01

210

Energy use and emissions from marine vessels: a total fuel life cycle approach.  

PubMed

Regional and global air pollution from marine transportation is a growing concern. In discerning the sources of such pollution, researchers have become interested in tracking where along the total fuel life cycle these emissions occur. In addition, new efforts to introduce alternative fuels in marine vessels have raised questions about the energy use and environmental impacts of such fuels. To address these issues, this paper presents the Total Energy and Emissions Analysis for Marine Systems (TEAMS) model. TEAMS can be used to analyze total fuel life cycle emissions and energy use from marine vessels. TEAMS captures "well-to-hull" emissions, that is, emissions along the entire fuel pathway, including extraction, processing, distribution, and use in vessels. TEAMS conducts analyses for six fuel pathways: (1) petroleum to residual oil, (2) petroleum to conventional diesel, (3) petroleum to low-sulfur diesel, (4) natural gas to compressed natural gas, (5) natural gas to Fischer-Tropsch diesel, and (6) soybeans to biodiesel. TEAMS calculates total fuel-cycle emissions of three greenhouse gases (carbon dioxide, nitrous oxide, and methane) and five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides, particulate matter with aerodynamic diameters of 10 microm or less, and sulfur oxides). TEAMS also calculates total energy consumption, fossil fuel consumption, and petroleum consumption associated with each of its six fuel cycles. TEAMS can be used to study emissions from a variety of user-defined vessels. This paper presents TEAMS and provides example modeling results for three case studies using alternative fuels: a passenger ferry, a tanker vessel, and a container ship. PMID:17269235

Winebrake, James J; Corbett, James J; Meyer, Patrick E

2007-01-01

211

Energy and carbon dioxide (CO2) balance of logging residues as alternative energy resources: system analysis based on the method of a life cycle inventory (LCI) analysis  

Microsoft Academic Search

Using the method of a life cycle inventory (LCI) analysis, the energy balance and the carbon dioxide (CO2) emission of logging residues from Japanese conventional forestry as alternative energy resources were analyzed over the entire life cycle of the residues. The fuel consumption for forestry machines was measured in field experiments for harvesting and transporting logging residues at forestry operating

Takuyuki Yoshioka; Kazuhiro Aruga; Toshio Nitami; Hiroshi Kobayashi; Hideo Sakai

2005-01-01

212

The sensitivity of the energy budget and hydrological cycle to CO2 and solar forcing  

NASA Astrophysics Data System (ADS)

The transient responses of the energy budget and the hydrological cycle to CO2 and solar forcings of the same magnitude in a global climate model are quantified in this study. Idealized simulations are designed to test the assumption that the responses to forcings are linearly additive, i.e. whether the response to individual forcings can be added to estimate the response to the combined forcing, and to understand the physical processes occurring as a response to a surface warming caused by CO2 or solar forcing increases of the same magnitude. For the global climate model considered, the responses of most variables of the energy budget and hydrological cycle, including surface temperature, do not add linearly. A separation of the response into a forcing and a feedback term shows that for precipitation, this non-linearity arises from the feedback term, i.e. from the non-linearity of the temperature response and the changes in the water cycle resulting from it. Further, changes in the energy budget show that less energy is available at the surface for global annual mean latent heat flux, and hence global annual mean precipitation, in simulations of transient CO2 concentration increase compared to simulations with an equivalent transient increase in the solar constant. On the other hand, lower tropospheric water vapor increases more in simulations with CO2 compared to solar forcing increase of the same magnitude. The response in precipitation is therefore more muted compared to the response in water vapor in CO2 forcing simulations, leading to a larger increase in residence time of water vapor in the atmosphere compared to solar forcing simulations. Finally, energy budget calculations show that poleward atmospheric energy transport increases more in solar forcing compared to equivalent CO2 forcing simulations, which is in line with the identified strong increase in large-scale precipitation in solar forcing scenarios.

Schaller, N.; Cermak, J.; Wild, M.; Knutti, R.

2013-03-01

213

The sensitivity of the modeled energy budget and hydrological cycle to CO2 and solar forcing  

NASA Astrophysics Data System (ADS)

The transient responses of the energy budget and the hydrological cycle to CO2 and solar forcings of the same magnitude in a global climate model are quantified in this study. Idealized simulations are designed to test the assumption that the responses to forcings are linearly additive, i.e. whether the response to individual forcings can be added to estimate the responses to the combined forcing, and to understand the physical processes occurring as a response to a surface warming caused by CO2 or solar forcing increases of the same magnitude. For the global climate model considered, the responses of most variables of the energy budget and hydrological cycle, including surface temperature, do not add linearly. A separation of the response into a forcing and a feedback term shows that for precipitation, this non-linearity arises from the feedback term, i.e. from the non-linearity of the temperature response and the changes in the water cycle resulting from it. Further, changes in the energy budget show that less energy is available at the surface for global annual mean latent heat flux, and hence global annual mean precipitation, in simulations of transient CO2 concentration increase compared to simulations with an equivalent transient increase in the solar constant. On the other hand, lower tropospheric water vapor increase is similar between simulations with CO2 and solar forcing increase of the same magnitude. The response in precipitation is therefore more muted compared to the response in water vapor in CO2 forcing simulations, leading to a larger increase in residence time of water vapor in the atmosphere compared to solar forcing simulations. Finally, energy budget calculations show that poleward atmospheric energy transport increases more in solar forcing compared to equivalent CO2 forcing simulations, which is in line with the identified strong increase in large-scale precipitation in solar forcing scenarios.

Schaller, N.; Cermak, J.; Wild, M.; Knutti, R.

2013-08-01

214

The Path to Sustainable Nuclear Energy. Basic and Applied Research Opportunities for Advanced Fuel Cycles  

SciTech Connect

The objective of this report is to identify new basic science that will be the foundation for advances in nuclear fuel-cycle technology in the near term, and for changing the nature of fuel cycles and of the nuclear energy industry in the long term. The goals are to enhance the development of nuclear energy, to maximize energy production in nuclear reactor parks, and to minimize radioactive wastes, other environmental impacts, and proliferation risks. The limitations of the once-through fuel cycle can be overcome by adopting a closed fuel cycle, in which the irradiated fuel is reprocessed and its components are separated into streams that are recycled into a reactor or disposed of in appropriate waste forms. The recycled fuel is irradiated in a reactor, where certain constituents are partially transmuted into heavier isotopes via neutron capture or into lighter isotopes via fission. Fast reactors are required to complete the transmutation of long-lived isotopes. Closed fuel cycles are encompassed by the Department of Energy?s Advanced Fuel Cycle Initiative (AFCI), to which basic scientific research can contribute. Two nuclear reactor system architectures can meet the AFCI objectives: a ?single-tier? system or a ?dual-tier? system. Both begin with light water reactors and incorporate fast reactors. The ?dual-tier? systems transmute some plutonium and neptunium in light water reactors and all remaining transuranic elements (TRUs) in a closed-cycle fast reactor. Basic science initiatives are needed in two broad areas: ? Near-term impacts that can enhance the development of either ?single-tier? or ?dual-tier? AFCI systems, primarily within the next 20 years, through basic research. Examples: Dissolution of spent fuel, separations of elements for TRU recycling and transmutation Design, synthesis, and testing of inert matrix nuclear fuels and non-oxide fuels Invention and development of accurate on-line monitoring systems for chemical and nuclear species in the nuclear fuel cycle Development of advanced tools for designing reactors with reduced margins and lower costs ? Long-term nuclear reactor development requires basic science breakthroughs: Understanding of materials behavior under extreme environmental conditions Creation of new, efficient, environmentally benign chemical separations methods Modeling and simulation to improve nuclear reaction cross-section data, design new materials and separation system, and propagate uncertainties within the fuel cycle Improvement of proliferation resistance by strengthening safeguards technologies and decreasing the attractiveness of nuclear materials A series of translational tools is proposed to advance the AFCI objectives and to bring the basic science concepts and processes promptly into the technological sphere. These tools have the potential to revolutionize the approach to nuclear engineering R&D by replacing lengthy experimental campaigns with a rigorous approach based on modeling, key fundamental experiments, and advanced simulations.

Finck, P.; Edelstein, N.; Allen, T.; Burns, C.; Chadwick, M.; Corradini, M.; Dixon, D.; Goff, M.; Laidler, J.; McCarthy, K.; Moyer, B.; Nash, K.; Navrotsky, A.; Oblozinsky, P.; Pasamehmetoglu, K.; Peterson, P.; Sackett, J.; Sickafus, K. E.; Tulenko, J.; Weber, W.; Morss, L.; Henry, G.

2005-09-01

215

Life-cycle energy savings potential from aluminum-intensive vehicles  

SciTech Connect

The life-cycle energy and fuel-use impacts of US-produced aluminum-intensive passenger cars and passenger trucks are assessed. The energy analysis includes vehicle fuel consumption, material production energy, and recycling energy. A model that stimulates market dynamics was used to project aluminum-intensive vehicle market shares and national energy savings potential for the period between 2005 and 2030. We conclude that there is a net energy savings with the use of aluminum-intensive vehicles. Manufacturing costs must be reduced to achieve significant market penetration of aluminum-intensive vehicles. The petroleum energy saved from improved fuel efficiency offsets the additional energy needed to manufacture aluminum compared to steel. The energy needed to make aluminum can be reduced further if wrought aluminum is recycled back to wrought aluminum. We find that oil use is displaced by additional use of natural gas and nonfossil energy, but use of coal is lower. Many of the results are not necessarily applicable to vehicles built outside of the United States, but others could be used with caution.

Stodolsky, F.; Vyas, A.; Cuenca, R.; Gaines, L.

1995-07-01

216

Open-cycle Ocean Thermal Energy Conversion (OTEC): Status and potential  

NASA Astrophysics Data System (ADS)

Tropical oceans with a 20 C or more temperature difference between surface and deep water represent a vast resource of renewable thermal energy. One of the methods of harnessing this resource is an open-cycle Ocean Thermal Energy Conversion (OTEC) system utilizing steam evaporated from the surface water for powering the turbine. In this paper, the state of the art of research and component development, as related to heat and mass transfer processes, power production, noncondensable gas handling, and seawater flow hydraulics, are described through an illustrated preliminary design study of a 1-MW facility.

Bharathan, D.

1984-08-01

217

High energy solar cosmic rays detection by the Baksan air shower arrays, Andyrchy and Carpet , during 23rd solar cycle  

NASA Astrophysics Data System (ADS)

Total counting rate of two scintillation Baksan air shower arrays "Andyrchy" and "Carpet" was examined during Ground Level Enhancements (GLEs) observed in the 23rd cycle of solar activity. Significant excesses above the galactic cosmic ray background have been found during several GLE events. The magnitude of increases at the peak of intensity-time profiles during different GLEs amounts to 4-14 st.dev. (0.12-0.44% excess) by the 15-min data of "Andyrchy". The "Carpet" array has two times higher statistical accuracy than "Andyrchy" under the same observation conditions. The data of both Baksan shower arrays are compared with the neutron monitors data at Apatity and Moscow. The total counting rate of both arrays consists mainly of single detector events(one-fold). The counting rate of two-fold, three-fold and greater events are few percents of total one. One-fold component is produced by secondary single muons and by small local air showers (electrons and gamma rays). The energy of primary hadrons caused one- fold component is higher than that for neutron monitors and amounts a few tens of GeV. The data of two air shower arrays, "Andyrchy" and "Carpet", open a new interesting possibility to study solar cosmic rays in the energy range of few tens of GeV.

Alekseenko, V.; Karpov, S.; Karpova, Z.; Khaerdinov, N.; Petkov, V.; Poddubny, V.; Zaichenko, A.

218

High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion  

NASA Technical Reports Server (NTRS)

For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a partial energy conversion system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.

Juhasz, Albert J.; Sawicki, Jerzy T.

2003-01-01

219

Comparing Life-Cycle Costs of ESPCs and Appropriations-Funded Energy Projects: An Update to the 2002 Report  

SciTech Connect

A study was sponsored by FEMP in 2001 - 2002 to develop methods to compare life-cycle costs of federal energy conservation projects carried out through energy savings performance contracts (ESPCs) and projects that are directly funded by appropriations. The study described in this report follows up on the original work, taking advantage of new pricing data on equipment and on $500 million worth of Super ESPC projects awarded since the end of FY 2001. The methods developed to compare life-cycle costs of ESPCs and directly funded energy projects are based on the following tasks: (1) Verify the parity of equipment prices in ESPC vs. directly funded projects; (2) Develop a representative energy conservation project; (3) Determine representative cycle times for both ESPCs and appropriations-funded projects; (4) Model the representative energy project implemented through an ESPC and through appropriations funding; and (5) Calculate the life-cycle costs for each project.

Shonder, John A [ORNL; Hughes, Patrick [ORNL; Atkin, Erica [ORNL

2006-11-01

220

Technology for Bayton-cycle powerplants using solar and nuclear energy  

NASA Technical Reports Server (NTRS)

Brayton cycle gas turbines have the potential to use either solar heat or nuclear reactors for generating from tens of kilowatts to tens of megawatts of power in space, all this from a single technology for the power generating system. Their development for solar energy dynamic power generation for the space station could be the first step in an evolution of such powerplants for a very wide range of applications. At the low power level of only 10 kWe, a power generating system has already demonstrated overall efficiency of 0.29 and operated 38 000 hr. Tests of improved components show that these components would raise that efficiency to 0.32, a value twice that demonstrated by any alternate concept. Because of this high efficiency, solar Brayton cycle power generators offer the potential to increase power per unit of solar collector area to levels exceeding four times that from photovoltaic powerplants using present technology for silicon solar cells. The technologies for solar mirrors and heat receivers are reviewed and assessed. This Brayton technology for solar powerplants is equally suitable for use with the nuclear reactors. The available long time creep data on the tantalum alloy ASTAR-811C show that such Brayton cycles can evolve to cycle peak temperatures of 1500 K (2240 F). And this same technology can be extended to generate 10 to 100 MW in space by exploiting existing technology for terrestrial gas turbines in the fields of both aircraft propulsion and stationary power generation.

English, R. E.

1986-01-01

221

A Life-Cycle Assessment of Biofuels: Tracing Energy and Carbon through a Fuel-Production System  

ERIC Educational Resources Information Center

A life-cycle assessment (LCA) is a tool used by engineers to make measurements of net energy, greenhouse gas production, water consumption, and other items of concern. This article describes an activity designed to walk students through the qualitative part of an LCA. It asks them to consider the life-cycle costs of ethanol production, in terms of…

Krauskopf, Sara

2010-01-01

222

Review of cooperative research on thorium fuel cycle as a promising energy source in the next century  

Microsoft Academic Search

Aiming at building up the scientific and technical foundation for the development of the thorium fuel cycle, we carried out a cooperative fundamental study on this cycle as a promising energy source in and after the next century by the support of Grant-in-Aid for Scientific Research by the Ministry of Education, Science and Culture of Japanese Government from April 1988

I Kimura

1995-01-01

223

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

SciTech Connect

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

Puig, Rita, E-mail: rita.puig@eei.upc.edu [Escola d’Enginyeria d’Igualada (EEI), Universitat Politècnica de Catalunya (UPC), Plaça del Rei, 15, 08700 Igualada (Spain); Fullana-i-Palmer, Pere [UNESCO Chair in Life Cycle and Climate Change, Escola Superior de Comerç Internacional, Universitat Pompeu Fabra (UPF), c/Passeig Pujades, 1, 08003 Barcelona (Spain); Baquero, Grau; Riba, Jordi-Roger [Escola d’Enginyeria d’Igualada (EEI), Universitat Politècnica de Catalunya (UPC), Plaça del Rei, 15, 08700 Igualada (Spain); Bala, Alba [UNESCO Chair in Life Cycle and Climate Change, Escola Superior de Comerç Internacional, Universitat Pompeu Fabra (UPF), c/Passeig Pujades, 1, 08003 Barcelona (Spain)

2013-12-15

224

Towards Robust Energy Systems Modeling: Examinging Uncertainty in Fossil Fuel-Based Life Cycle Assessment Approaches  

NASA Astrophysics Data System (ADS)

Increasing concerns about the environmental impacts of fossil fuels used in the U.S. transportation and electricity sectors have spurred interest in alternate energy sources, such as natural gas and biofuels. Life cycle assessment (LCA) methods can be used to estimate the environmental impacts of incumbent energy sources and potential impact reductions achievable through the use of alternate energy sources. Some recent U.S. climate policies have used the results of LCAs to encourage the use of low carbon fuels to meet future energy demands in the U.S. However, the LCA methods used to estimate potential reductions in environmental impact have some drawbacks. First, the LCAs are predominantly based on deterministic approaches that do not account for any uncertainty inherent in life cycle data and methods. Such methods overstate the accuracy of the point estimate results, which could in turn lead to incorrect and (consequent) expensive decision-making. Second, system boundaries considered by most LCA studies tend to be limited (considered a manifestation of uncertainty in LCA). Although LCAs can estimate the benefits of transitioning to energy systems of lower environmental impact, they may not be able to characterize real world systems perfectly. Improved modeling of energy systems mechanisms can provide more accurate representations of reality and define more likely limits on potential environmental impact reductions. This dissertation quantitatively and qualitatively examines the limitations in LCA studies outlined previously. The first three research chapters address the uncertainty in life cycle greenhouse gas (GHG) emissions associated with petroleum-based fuels, natural gas and coal consumed in the U.S. The uncertainty in life cycle GHG emissions from fossil fuels was found to range between 13 and 18% of their respective mean values. For instance, the 90% confidence interval of the life cycle GHG emissions of average natural gas consumed in the U.S was found to range between -8 to 9% (17%) of the mean value of 66 g CO2e/MJ. Results indicate that uncertainty affects the conclusions of comparative life cycle assessments, especially when differences in average environmental impacts between two competing fuels/products are small. In the final two research chapters of this thesis, system boundary limitations in LCA are addressed. Simplified economic dispatch models for are developed to examine changes in regional power plant dispatch that occur when coal power plants are retired and when natural gas prices drop. These models better reflect reality by estimating the order in which existing power plants are dispatched to meet electricity demand based on short-run marginal costs. Results indicate that the reduction in air emissions are lower than suggested by LCA studies, since they generally do not include the complexity of regional electricity grids, predominantly driven by comparative fuel prices. For instance, comparison, this study estimates 7-15% reductions in emissions with low natural gas prices. Although this is a significant reduction in itself, it is still lower than the benefits reported in traditional life cycle comparisons of coal and natural gas-based power (close to 50%), mainly due to the effects of plant dispatch.

Venkatesh, Aranya

225

Thermal energy storage for low grade heat in the organic Rankine cycle  

NASA Astrophysics Data System (ADS)

Limits of efficiencies cause immense amounts of thermal energy in the form of waste heat to be vented to the atmosphere. Up to 60% of unrecovered waste heat is classified as low or ultra-low quality, making recovery difficult or inefficient. The organic Rankine cycle can be used to generate mechanical power and electricity from these low temperatures where other thermal cycles are impractical. A variety of organic working fluids are available to optimize the ORC for any target temperature range. San Diego State University has one such experimental ORC using R245fa, and has been experimenting with multiple expanders. One limitation of recovering waste heat is the sporadic or cyclical nature common to its production. This inconsistency makes sizing heat recovery ORC systems difficult for a variety of reasons including off-design-point efficiency loss, increased attrition from varying loads, unreliable outputs, and overall system costs. Thermal energy storage systems can address all of these issues by smoothing the thermal input to a constant and reliable level and providing back-up capacity for times when the thermal input is deactivated. Multiple types of thermal energy storage have been explored including sensible, latent, and thermochemical. Latent heat storage involves storing thermal energy in the reversible phase change of a phase change material, or PCM, and can have several advantages over other modalities including energy storage density, cost, simplicity, reliability, relatively constant temperature output, and temperature customizability. The largest obstacles to using latent heat storage include heat transfer rates, thermal cycling stability, and potentially corrosive PCMs. Targeting 86°C, the operating temperature of SDSU's experimental ORC, multiple potential materials were explored and tested as potential PCMs including Magnesium Chloride Hexahydrate (MgCl2?6H2O), Magnesium Nitrate Hexahydrate (Mg(NO3)2?6H 2O), montan wax, and carnauba wax. The addition of graphite to augment heat transfer rates was also tested. Melting and solidification temperatures largely matched predictions. The magnesium salts were found to be less stable under thermal cycling than the waxes. Graphite was only soluble in the waxes. Mixtures of magnesium salts and waxes yielded a layered composite with the less dense waxes creating a sealing layer over the salt layer that significantly increased the stability of the magnesium salts. Research into optimum heat exchangers and storage vessels for these applications indicates that horizontally oriented aluminum pipes with vertically oriented aluminum fins would be the best method of storing and retrieving energy. Fin spacing can be predicted by an equation based on target temperatures and PCM characteristics.

Soda, Michael John

226

Rankine cycle condenser pressure control using an energy conversion device bypass valve  

DOEpatents

The disclosure provides a waste heat recovery system and method in which pressure in a Rankine cycle (RC) system of the WHR system is regulated by diverting working fluid from entering an inlet of an energy conversion device of the RC system. In the system, an inlet of a controllable bypass valve is fluidly coupled to a working fluid path upstream of an energy conversion device of the RC system, and an outlet of the bypass valve is fluidly coupled to the working fluid path upstream of the condenser of the RC system such that working fluid passing through the bypass valve bypasses the energy conversion device and increases the pressure in a condenser. A controller determines the temperature and pressure of the working fluid and controls the bypass valve to regulate pressure in the condenser.

Ernst, Timothy C; Nelson, Christopher R; Zigan, James A

2014-04-01

227

On the nonlinear feedback loop and energy cycle of the non-dissipative Lorenz model  

NASA Astrophysics Data System (ADS)

In this study, we discuss the role of the nonlinear terms and linear (heating) term in the energy cycle of the three-dimensional (X-Y-Z) non-dissipative Lorenz model (3D-NLM). (X, Y, Z) represent the solutions in the phase space. We first present the closed-form solution to the nonlinear equation d2 X/d?2+ (X2/2)X = 0, ? is a non-dimensional time, which was never documented in the literature. As the solution is oscillatory (wave-like) and the nonlinear term (X2) is associated with the nonlinear feedback loop, it is suggested that the nonlinear feedback loop may act as a restoring force. We then show that the competing impact of nonlinear restoring force and linear (heating) force determines the partitions of the averaged available potential energy from Y and Z modes, respectively, denoted as APEY and APEZ. Based on the energy analysis, an energy cycle with four different regimes is identified with the following four points: A(X, Y) = (0,0), B = (Xt, Yt), C = (Xm, Ym), and D = (Xt, -Yt). Point A is a saddle point. The initial perturbation (X, Y, Z) = (0, 1, 0) gives (Xt, Yt) = ( 2?r , r) and (Xm, Ym) = (2 ?r , 0). ? is the Prandtl number, and r is the normalized Rayleigh number. The energy cycle starts at (near) point A, A+ = (0, 0+) to be specific, goes through B, C, and D, and returns back to A, i.e., A- = (0,0-). From point A to point B, denoted as Leg A-B, where the linear (heating) force dominates, the solution X grows gradually with { KE↑, APEY↓, APEZ↓}. KE is the averaged kinetic energy. We use the upper arrow (↑) and down arrow (↓) to indicate an increase and decrease, respectively. In Leg B-C (or C-D) where nonlinear restoring force becomes dominant, the solution X increases (or decreases) rapidly with KE↑, APEY↑, APEZ↓ (or KE↓, APEY↓, APEZ↑). In Leg D-A, the solution X decreases slowly with {KE↓, APEY↑, APEZ↑ }. As point A is a saddle point, the aforementioned cycle may be only half of a "big" cycle, displaying the wing pattern of a glasswinged butterfly, and the other half cycle is antisymmetric with respect to the origin, namely B = (-Xt, -Yt), C = (-Xm, 0), and D = (-Xt, Yt).

Shen, B.-W.

2014-04-01

228

SYNTHESIS OF A MODEL SYSTEM FOR THE PRIMARY ENERGY CONVERSION REACTIONS IN PHOTOSYNTHESIS*  

PubMed Central

A model system is constructed which, like the photosynthetic apparatus of green plants, can convert light to chemical free energy through pigment-sensitized photooxidation of water. The system has two light-harvesting subunits connected electrically in series. Each subunit is made of a multimolecular layer of Zn(II)-tetraphenylporphyrin deposited on a clean aluminum surface and immersed in an aqueous mixture of potassium ferri- and ferrocyanide. Upon illumination by amber light, charge transfer takes place across more than 70 molecular layers of the pigment with a photoelectromotive force of 1.1 to 1.3 volts per subunit. With NADP as the electron acceptor and NADP-reductase as a mediator, the system can photooxidize water to oxygen gas. With these model experiments as a guide, a molecular mechanism for the primary energy conversion reactions in photosynthesis is formulated that offers a unified interpretation of most of the relevant observations reported in the literature. PMID:4389747

Wang, Jui H.

1969-01-01

229

Reduction of Thermal Energy Loss in Cyclic Operation of Refrigeration Cycle  

NASA Astrophysics Data System (ADS)

Investigation of thermal energy loss in cyclic operation of refrigeration cycle in a refrigerator-freezer were made. The energy loss was found to consist of three parts ; hot gas-refrigerant entering loss, cooling lag loss, and evaporator superheat loss. Hot gas-refrigerant entering loss is occured when high temperature gaseous refrigerant in a condenser flows into an evaporator to heat up the refrigerant in it. Main results are as follows ; 1) Hot gas-refrigerant entering loss, which was the most dominant, was found to be from 7.6 to 12.3% (for reciprocationg compressor) and from 11.9 to 17.4% (for rotary compressor) of the cooling load, respectively. 2) The thermal energy loss was confirmed to be able to be reduced when hot gas-refrigerant was restricted to flow in the evaporator with control valves. It follows to reduce electrical power consumption by 10 and 15%, in the case of reciprocating compressor and of rotary compressor, respectively. 3) Cycle frequency was made to be optimized theoretically and experimentally in the case of with and without valves.

Gommori, Masahiko; Kogure, Hiroshi; Hara, Toshitsugu

230

Energy metabolism and glutamate-glutamine cycle in the brain: a stoichiometric modeling perspective  

PubMed Central

Background The energetics of cerebral activity critically relies on the functional and metabolic interactions between neurons and astrocytes. Important open questions include the relation between neuronal versus astrocytic energy demand, glucose uptake and intercellular lactate transfer, as well as their dependence on the level of activity. Results We have developed a large-scale, constraint-based network model of the metabolic partnership between astrocytes and glutamatergic neurons that allows for a quantitative appraisal of the extent to which stoichiometry alone drives the energetics of the system. We find that the velocity of the glutamate-glutamine cycle (Vcyc) explains part of the uncoupling between glucose and oxygen utilization at increasing Vcyc levels. Thus, we are able to characterize different activation states in terms of the tissue oxygen-glucose index (OGI). Calculations show that glucose is taken up and metabolized according to cellular energy requirements, and that partitioning of the sugar between different cell types is not significantly affected by Vcyc. Furthermore, both the direction and magnitude of the lactate shuttle between neurons and astrocytes turn out to depend on the relative cell glucose uptake while being roughly independent of Vcyc. Conclusions These findings suggest that, in absence of ad hoc activity-related constraints on neuronal and astrocytic metabolism, the glutamate-glutamine cycle does not control the relative energy demand of neurons and astrocytes, and hence their glucose uptake and lactate exchange. PMID:24112710

2013-01-01

231

Experimental Performance Analysis of Supercritical CO2 Thermodynamic Cycle Powered by Solar Energy  

NASA Astrophysics Data System (ADS)

The interests in using carbon dioxide as working fluid increase since the Montreal and Kyoto Protocols were made. In this paper, a complete effort was made to study the performance of CO2 Rankine cycle powered by solar energy experimentally. The system utilizes evacuated solar collectors to convert CO2 into high-temperature supercritical state, used to produce electrical energy and thermal energy, which could be used for air conditioning and hot water supply and so on. The system performances were tested not only in summer, but also in winter; not only in sunny day, but also in cloudy day. The interest of the paper is the solar collector efficiency, because the absorbed heat quantity in the collector can be utilized for power generation and heat supply and other useful outputs. The results show that annually-averaged solar collector efficiency was measured at about 60.4%. The study shows the potential of the application of the solar powered CO2 cycle as a distributed power/heat generation system.

Zhang, X. R.; Yamaguchi, H.; Fujima, K.; Enomoto, M.; Sawada, N.

2006-05-01

232

A new one-dimensional simple energy balance and carbon cycle coupled model for global warming simulation  

NASA Astrophysics Data System (ADS)

Global warming and accompanying climate change may be caused by an increase in atmospheric greenhouse gasses generated by anthropogenic activities. In order to supply such a mechanism of global warming with a quantitative underpinning, we need to understand the multifaceted roles of the Earth's energy balance and material cycles. In this study, we propose a new one-dimensional simple Earth system model. The model consists of carbon and energy balance submodels with a north-south zonal structure. The two submodels are coupled by interactive feedback processes such as CO2 fertilization of net primary production (NPP) and temperature dependencies of NPP, soil respiration, and ocean surface chemistry. The most important characteristics of the model are not only that the model requires a relatively short calculation time for carbon and energy simulation compared with a General Circulation Model (GCM) and an Earth system Model of Intermediate Complexity (EMIC), but also that the model can simulate average latitudinal variations. In order to analyze the response of the Earth system due to increasing greenhouse gasses, several simulations were conducted in one dimension from the years 1750 to 2000. Evaluating terrestrial and oceanic carbon uptake output of the model in the meridional direction through comparison with observations and satellite data, we analyzed the time variation patterns of air temperature in low- and middle-latitude belts. The model successfully reproduced the temporal variation in each latitude belt and the latitudinal distribution pattern of carbon uptake. Therefore, this model could more accurately demonstrate a difference in the latitudinal response of air temperature than existing models. As a result of the model evaluations, we concluded that this new one-dimensional simple Earth system model is a good tool for conducting global warming simulations. From future projections using various emission scenarios, we showed that the spatial distribution of terrestrial carbon uptake may vary greatly, not only among models used for climate change simulations, but also amongst emission scenarios.

Murakami, Kazutaka; Sasai, Takahiro; Yamaguchi, Yasushi

2010-08-01

233

Energy storage in the primary step of the photocycle of bacteriorhodopsin.  

PubMed Central

A pulsed-dye laser low temperature photocalorimeter is used to study the enthalpy differences between light-adapted bacteriorhodopsin (bR568) and its primary photoproduct (K) at 77 K. A key feature of our experimental method is the use of the laser-induced photostationary state as an internal reference. Analyses of the forward (bR leads to K), reverse (K leads to bR), and mixed (bR in equilibrium K) photoreactions were carried out to measure delta H12 = EK - EbR. All three experiments yielded identical values of delta H12 within experimental error (delta Have12 = 15.8 +/- 2.5 kcal mol-1). Accordingly, the primary event in the photocycle of light-adapted bacteriorhodopsin stores approximately 30% of the absorbed photon energy at the 568-nm absorption maximum. We observe that the quantum yields phi f1(bR leads to K) and phi r2(K leads to bR) add up to unity within experimental error: phi f1 + phi r2 = 1.02 +/- 0.19 for phi f1 in the range 0.28-0.33. A theoretical analysis of energy storage in K suggests that at least one-half of the enthalpy difference between K and bR is associated with charge separation accompanying chromophore isomerization. PMID:6838982

Birge, R R; Cooper, T M

1983-01-01

234

Ground water geochemistry of short-term aquifer thermal energy storage test cycles  

SciTech Connect

The changes in the concentrations of Ca, dissolved silica, and alkalinity of the recovery waters of four short-term aquifer thermal energy storage test cycles with respect to the injection waters and the correlation of these concentrations with recovery water temperatures indicate that quartz and calcite dissolved during hot water storage. This hypothesis was supported by chemical equilibrium modeling and mass balance calculations. Magnesium concentrations were lower in recovery waters than in injection waters. Chemical modeling indicated that a Mg silicate (talc) could have precipitated. Potassium concentrations correlated well with temperatures, probably because of ion exchange involving potassium feldspars in the aquifer.

Holms, T.R.; Eisenreich, S.J.; Rosenberg, H.L.; Holm, N.P.

1987-06-01

235

Global Change Research Related in the Earth's Energy and Hydrologic Cycle  

NASA Technical Reports Server (NTRS)

The mission of the Global Change Research Related to the Earth's Energy and Hydrologic Cycle is to enhance the scientific knowledge and educational benefits obtained from NASA's Earth Science Enterprise and the U.S. Global Change Research Program, University of Alabama in Huntsville (UAH). This paper presents the final technical report on this collaborative effort. Various appendices include: A) Staff Travel Activities years one through three; B) Publications and Presentations years one through three; C) Education Activities; D) Students year one through three; E) Seminars year one through three; and F) Center for Applied Optics Projects.

Berry, Linda R.

2002-01-01

236

Thermodynamic systems analysis of open-cycle Ocean Thermal Energy Conversion (OTEC)  

NASA Astrophysics Data System (ADS)

This report describes an updated thermal-hydraulic systems analysis program called OTECSYS that studies the integrated performance of an open-cycle ocean thermal energy conversion (OTEC) plant, specifically, the effects of component performance, design parameters, and site specific resource data on the total system performance and plant size. OTECSYS can size the various open-cycle power cycle and hydraulic components. Models for the evaporator, mist eliminator, turbine-generator diffuser, direct-contact condenser, exhaust compressors, seawater pumps, and seawater piping are included, as are evaluations of the pressure drops associated with the intercomponent connections. It can also determine the required steam, cold seawater, and warm seawater flow rates. OTECSYS uses an approach similar to earlier work and integrates the most up-to-date developments in component performance and configuration. The program format allows the user to examine subsystem concepts not currently included by creating new component models. It will be useful to the OTEC plant designer who wants to quantify the design point sizing, performance, and power production using site-specific resource data. Detailed design trade-offs are easily evaluated, and several examples of these types of investigations are presented using plant size and power as criteria.

Parsons, B. K.; Bharathan, D.; Althof, J. A.

1985-09-01

237

Vacuum thermal cycle life testing of high temperature thermal energy storage  

NASA Astrophysics Data System (ADS)

An experimental program to investigate the corrosion compatibility of the high temperature thermal energy storage (TES) salts with Inconel-617 container was initiated at the Thermal Laboratory of the Wright Research and Development Center (WRDC) in 1985. Three fluoride eutectic mixtures: LiF-MgF2-KF, LiF-MgF2-NaF, and LiF-MgF2 having melting points in the neighborhood of 1000 K and heats of fusion above 750 kJ/kg were chosen. High purity analytical grade component salts were processed in oxygen and moisture-free inert atmosphere, and melted in situ in the Inconel-617 containers. The containers were sealed by electron beam-welding of the end caps thereby evacuating the void volume. The TES capsules thus formed were placed in a tubular vacuum furnace for continuous thermal cycle life testing by cycling them ±100 K from the eutectic temperature every 2 hours. The capsules have successfully undergone 40,000 hours and 10,000 cycles of testing as of April 1990 and continuing on the test. This is believed to be the longest record available on the TES corrosion compatibility data. The present results clearly indicate that careful processing and proper welding are key factors in obtaining a longlife TES salt-containment system.

Ponnappan, Rengasamy; Beam, Jerry E.

1991-01-01

238

Global Change Research Related to the Earth's Energy and Hydrologic Cycle  

NASA Technical Reports Server (NTRS)

The Institute for Global Change Research and Education (IGCRE) is a joint initiative of the Universities Space Research Association (USRA) and the University of Alabama in Huntsville (UAH) for coordinating and facilitating research and education relevant to global environmental change. Created in 1992 with primary support from the National Aeronautics and Space Administration (NASA), IGCRE fosters participation by university, private sector and government scientists who seek to develop long-term collaborative research in global change science, focusing on the role of water and energy in the Earth's atmosphere and physical climate system. IGCRE is also chartered to address educational needs of Earth system and global change science, including the preparation of future scientists and training of primary and secondary education teachers.

1998-01-01

239

Annual cycle of the global-mean energy budget in a mechanistic middle atmosphere GCM  

NASA Astrophysics Data System (ADS)

A new mechanistic climate model from the surface to the lower thermosphere is presented. The model is based on a standard spectral dynamical core and includes an idealized radiation scheme with continuous computation of energy fluxes. The surface energy budget is fully taken into account by means of a slap ocean with prescribed lateral oceanic heat-flux convergence. The moisture budget is based on a new transport scheme and simple parameterizations of condensation and convection. Subgrid-scale parameterizations include gravity waves and turbulent diffusion. Each parameterized process is formulated in an energy conserving fashion such that the resulting numerical error of the net radiation at the top of the atmosphere (RTOA) is about 0.2 W/m/m. The model shows a pronounced annual cycle of the RTOA of several W/m/m, with the minimum occurring in late NH winter. On a seasonal timescale this variation is synchronous with an equally strong imbalance at the surface. The annual cycle of the RTOA results from the hemispheric differences in the distribution of land and ocean surfaces, which are characterized by different heat capacities and albedos. While the absorbed solar radiation (ASR) is dominated by a semi-annual component associated with maximum absorption at the surface during the equinoxes, the global-mean surface temperature is governed by an annual component with a minimum during late NH winter. The reason is a smaller surface heat capacity in the NH, giving rise to global-mean cooling particularly during early NH winter. The annual cycle in the surface temperature then implies a corresponding behavior in the outgoing long-wave radiation (OLR), which gives the main contribution to the annual component of the RTOA. These mechanistic model results are supported by existing observational analyses. Analysing the global-mean energy budget as a function of height, the residual circulation is found to account for a downward dynamical energy flux from the stratosphere into the troposphere of about 1 W/m/m, which is consistently balanced in the model by a net upward radiation flux between about 300 and 10 hPa. The implications of this study are that 1) an imbalance in the RTOA may contain significant contributions from natural oceanic variability and 2) the dynamical energy flux from the middle into the lower atmosphere requires to include a realistic stratosphere in climate models.

Becker, Erich; Knoepfel, Rahel

2014-05-01

240

Energy harvesting based on piezoelectric Ericsson cycles in a piezoceramic material  

NASA Astrophysics Data System (ADS)

The possibility of recycling ambient energies with electric generators instead of using batteries with limited life spans has stimulated important research efforts over the past years. The integration of such generators into mainly autonomous low-power systems, for various industrial or domestic applications is envisioned. In particular, the present work deals with energy harvesting from mechanical vibrations. It is shown here that direct piezoelectric energy harvesting (short circuiting on an adapted resistance, for example) leads to relatively weak energy levels that are insufficient for an industrial development. By coupling an electric field and mechanical excitation on Ericsson-based cycles, the amplitude of the harvested energy can be highly increased, and can reach a maximum close to 100 times its initial value. To obtain such a gain, one needs to employ high electrical field levels (high amplitude, high frequency), which induce a non-linearity through the piezoceramic. A special dynamic hysteresis model has been developed to correctly take into account the material properties, and to provide a real estimation of the harvested energy. A large number of theoretical predictions and experimental results have been compared and are discussed herein, in order to validate the proposed solution.

Zhang, B.; Ducharne, B.; Guyomar, D.; Sebald, G.

2013-09-01

241

Life cycle assessment of thermal Waste-to-Energy technologies: Review and recommendations.  

PubMed

Life cycle assessment (LCA) has been used extensively within the recent decade to evaluate the environmental performance of thermal Waste-to-Energy (WtE) technologies: incineration, co-combustion, pyrolysis and gasification. A critical review was carried out involving 250 individual case-studies published in 136 peer-reviewed journal articles within 1995 and 2013. The studies were evaluated with respect to critical aspects such as: (i) goal and scope definitions (e.g. functional units, system boundaries, temporal and geographic scopes), (ii) detailed technology parameters (e.g. related to waste composition, technology, gas cleaning, energy recovery, residue management, and inventory data), and (iii) modeling principles (e.g. energy/mass calculation principles, energy substitution, inclusion of capital goods and uncertainty evaluation). Very few of the published studies provided full and transparent descriptions of all these aspects, in many cases preventing an evaluation of the validity of results, and limiting applicability of data and results in other contexts. The review clearly suggests that the quality of LCA studies of WtE technologies and systems including energy recovery can be significantly improved. Based on the review, a detailed overview of assumptions and modeling choices in existing literature is provided in conjunction with practical recommendations for state-of-the-art LCA of Waste-to-Energy. PMID:25052337

Astrup, Thomas Fruergaard; Tonini, Davide; Turconi, Roberto; Boldrin, Alessio

2014-07-19

242

Life cycle energy and greenhouse gas emissions of nuclear energy: A review  

Microsoft Academic Search

The increased urgency of dealing with mitigation of the looming climate change has sparked renewed interest in the nuclear energy option. There exists a substantial stream of research on the amount of embodied energy and greenhouse gas emissions associated with nuclear generated electricity. While conventional fossil fuelled power plants cause emissions almost exclusively from the plant site, the majority of

Manfred Lenzen

2008-01-01

243

Estimation of vertical sea level muon energy spectra from the latest primary cosmic ray elemental spectra  

NASA Astrophysics Data System (ADS)

The directly measured elemental spectra of primary cosmic rays obtained from Webber et al., Seo et al., Menn et al., Ryan et al. and experiments like JACEE, CRN, SOKOL, RICH on P, He, CNO, Ne-S and Fe have been considered to estimate the vertical sea level muon energy spectra. The primary elemental energy spectra of P, He, CNO, Ne-S and Fe available from the different experimental data duly fitted by power law are given by Np(E)dE = 1.2216E-2.68 dE [cm2 .s.sr.GeV/n]-1 NHe(E)dE = 0.0424E-2.59 dE [cm2 .s.sr.GeV/n]-1 NCNO(E)dE = 0.0026E-2.57 dE[cm2 .s.sr.GeV/n]-1 NNe-S(E)dE = 0.00066E-2.57 dE [cm2 .s.sr.GeV/n]-1 NF e(E)dE = 0.0056E-2.55 dE [cm2 .s.sr.GeV/n]-1 Using the conventional superposition model the all nucleon primary cosmic ray spectrum has been derived which is of the form N(E)dE = 1.42E-2.66 dE [cm2 .s.sr.GeV/n]-1 We have considered all these spectra separately as parents of the secondary mesons and finallty the sea level muon fluxes at 00 from each species have been derived. To evaluate the meson spectra which are the initial air shower interaction products initiated by the primary nucleon air collisions, the hadronic energy moments have been calculated from the CERN LEBCEHS data for pp collisions and FNAL data for ?p collisions. Pion production by secondary pions have been taken into account and the final total muon spectrum has been derived from pp rightarrow?± x, pp ? K± x, ?p ? ?± x channels. The Z-factors have been corrected for p-air collisions. We have adopted the constant values of ?p-air and ??-air crosssections which are 273 mb and 213 mb, respectively. The adopted inelastic cross-sections for pp and ?p interactions are 35 mb and 22 mb, respectively. The Q-G plasma correction of Z-factors have also been incorporated in the final form. The solution to the standard differential equation for mesons is considered for muon flux estimation from Ngenerations of the parent mesons. By this formulation vertical muon spectra from each element along with the total primary nucleon spectrum have been derived. We wanted to observe the different shape of the muon spectra evaluated from different elemental spectra and to make a comparative study of that. In this energy range (102 - 104 ) GeV we have observed that the majority of the total muon flux is coming from the proton spectra. The contribution from the other elemental spectra to the total muon flux is not at all comparable with that of proton spectra.

Mitra, M.; Molla, N. H.; Bhattacharyya, D. P.

244

Rock Cycle: Cycling  

NSDL National Science Digital Library

This Science Object is the third of four Science Objects in the Rocks SciPack. It explores the variables that contribute to rock transformation and the continuous processes of rock formation that constitute the rock cycle. The rock cycle provides an example of the transfer of energy and mass in the Earth system. Earth is a closed system containing essentially a fixed amount of each element. Movement of matter is driven by the Earth's internal and external sources of energy, and is often accompanied by changes in the physical and chemical properties of the matter. Minerals are made, dissolved, and remade--on the Earth's surface, in the oceans, and in the hot, high-pressure layers beneath the crust. The total amount of material stays the same as its forms change. Learning Outcomes:? Recognize the formation and transformation processes as part of a continuing cycle.? Identify that while the form and location of different rocks change over time, the amount of material and the distribution among the elements remains constant.? Explain the different processes or paths that each type of rock may take in the rock cycle.

National Science Teachers Association (NSTA)

2006-11-01

245

Operating Conditions of a Three-stage Combined Power Cycle using Cold Energy for Maximizing Exergetic Efficiency  

NASA Astrophysics Data System (ADS)

Waste heat utilization is a fundamental approach to end-use energy savings. Medium or low temperature waste heat is not usable unless its temperature level matches the demand. From this standpoint, power generation from medium or low temperature waste heat is beneficial because it improves the availability of the energy by converting waste heat into electricity or mechanical work. Conventional waste heat driven power generation cycles, such as the Kalina cycle, attain relatively low thermal efficiencies because of the low exergy in medium or low temperature heat. This paper proposes a three-stage combined power cycle using cold energy for power generation from medium temperature (?200°C)waste heat. The system consists of an ammonia-water Rankine cycle, an ethane-propane Rankine cycle and a liquefied natural gas direct expansion cycle. A cycle simulation of the system is executed, and the operating conditions where the exergetic efficiency is maximized are presented in this article. It is found that the exergetic efficiency reaches 31% under these operating conditions.

Miyazaki, Takahiko; Akisawa, Atsushi; Kashiwagi, Takao

246

Systems analysis techniques for annual cycle thermal energy storage solar systems  

SciTech Connect

Community-scale annual cycle thermal energy storage (ACTES) solar systems are promising options for building heat and cooling. A variety of approaches are feasible in modeling ACTES solar systems. The key parameter in such efforts, average collector efficiency, is first examined, followed by several approaches for simple and effective modeling. Methods are also examined for modeling building loads for structures based on both conventional and passive architectural designs. Two simulation models for sizing solar heating systems with annual storage are presented next. Validation is presented by comparison with the results of a study of seasonal storage systems based on SOLANSIM, an hour-by-hour simulation. These models are presently being used to examine the economic trade-off between collector field area and storage capacity. Finally, programs in the US Department of Energy directed toward developing either other system components such as improved tanks and solar ponds or design tools for ACTES solar systems are examined.

Baylin, F.; Sillman, S.

1980-07-01

247

Seasonality and seasonal affective disorder (SAD): an evolutionary viewpoint tied to energy conservation and reproductive cycles.  

PubMed

The characteristic symptoms of SAD, including hypersomnia and weight gain, might reflect a genetically programmed attempt to conserve energy during historically predictable periods of dwindling food supply. While this basic hypothesis has obvious conceptual appeal, few authors have considered the specific positive selection pressures that might have contributed to such a process. The goal of the current paper is to further develop an evolutionary model of SAD with a focus on energy conservation in the context of seasonal reproductive cycles. To accomplish this, seasonal data on birth rates are considered from an evolutionary viewpoint. There is considerable indirect evidence that in temperate climates, the symptoms of SAD reflect a predisposition for conception to occur in late spring/early summer to ensure a peak of births in the late winter/early spring. The adaptive value of such a pattern, and its putative role in natural selection in humans, is also discussed. PMID:15927269

Davis, Caroline; Levitan, Robert D

2005-07-01

248

Dietary energy availability affects primary and metastatic breast cancer and metformin efficacy  

PubMed Central

Dietary energy restriction has been shown to repress both mammary tumorigenesis and aggressive mammary tumor growth in animal studies. Metformin, a caloric restriction mimetic, has a long history of safe use as an insulin sensitizer in diabetics and has been shown to reduce cancer incidence and cancer-related mortality in humans. To determine the potential impact of dietary energy availability and metformin therapy on aggressive breast tumor growth and metastasis, an orthotopic syngeneic model using triple negative 66cl4 tumor cells in Balb/c mice was employed. The effect of dietary restriction, a standard maintenance diet or a diet with high levels of free sugar, were tested for their effects on tumor growth and secondary metastases to the lung. Metformin therapy with the various diets indicated that metformin can be highly effective at suppressing systemic metabolic biomarkers such as IGF-1, insulin and glucose, especially in the high energy diet treated animals. Long-term metformin treatment demonstrated moderate yet significant effects on primary tumor growth, most significantly in conjunction with the high energy diet. When compared to the control diet, the high energy diet promoted tumor growth, expression of the inflammatory adipokines leptin and resistin, induced lung priming by bone marrow-derived myeloid cells and promoted metastatic potential. Metformin had no effect on adipokine expression or the development of lung metastases with the standard or the high energy diet. These data indicate that metformin may have tumor suppressing activity where a metabolic phenotype of high fuel intake, metabolic syndrome, and diabetes exist, but may have little or no effect on events controlling the metastatic niche driven by proinflammatory events. PMID:20204498

Phoenix, Kathryn N.; Vumbaca, Frank; Fox, Melissa M.; Evans, Rebecca

2010-01-01

249

Extent of partial ice cover due to carbon cycle feedback in a zonal energy balance model Hydrology and Earth System Sciences, 7(2), 213219 (2003) EGU  

E-print Network

Extent of partial ice cover due to carbon cycle feedback in a zonal energy balance model 213 for corresponding author: chg@ceh.ac.uk Abstract A global carbon cycle is introduced into a zonally averaged energy, it is found that inclusion of a closed carbon cycle reduces the range of insolation over which stable partial

Boyer, Edmond

250

Innovative turbine concepts for open-cycle OTEC (Ocean Thermal Energy Conversion)  

NASA Astrophysics Data System (ADS)

The results are summarized of preliminary studies conducted to identify and evaluate three innovative concepts for an open cycle ocean thermal energy conversion (OTEC) steam turbine that could significantly reduce the cost of OTEC electrical power plants. The three concepts are: (1) a crossflow turbine, (2) a vertical axis, axial flow turbine, and (3) a double flow, radial inflow turbine with mixed flow blading. In all cases, the innovation involves the use of lightweight, composite plastic blading and a physical geometry that facilitates efficient fluid flow to and from the other major system components and reduces the structural requirements for both the turbine or the system vacuum enclosure, or both. The performance, mechanical design, and cost of each of the concepts are developed to varying degrees but in sufficient detail to show that the potential exists for cost reductions to the goals established in the U.S. Department of Energy's planning documents. Specifically, results showed that an axial turbine operating with 33 percent higher steam throughput and 7 percent lower efficiency than the most efficient configuration provides the most cost effective open-cycle OTEC system. The vacuum enclosure can be significantly modified to reduce costs by establishing better interfaces with the system.

1989-12-01

251

Study on fission blanket fuel cycling of a fusion-fission hybrid energy generation system  

NASA Astrophysics Data System (ADS)

This paper presents a preliminary study on neutron physics characteristics of a light water cooled fission blanket for a new type subcritical fusion-fission hybrid reactor aiming at electric power generation with low technical limits of fission fuel. The major objective is to study the fission fuel cycling performance in the blanket, which may possess significant impacts on the feasibility of the new concept of fusion-fission hybrid reactor with a high energy gain (M) and tritium breeding ratio (TBR). The COUPLE2 code developed by the Institute of Nuclear and New Energy Technology of Tsinghua University is employed to simulate the neutronic behaviour in the blanket. COUPLE2 combines the particle transport code MCNPX with the fuel depletion code ORIGEN2. The code calculation results show that soft neutron spectrum can yield M > 20 while maintaining TBR >1.15 and the conversion ratio of fissile materials CR > 1 in a reasonably long refuelling cycle (>five years). The preliminary results also indicate that it is rather promising to design a high-performance light water cooled fission blanket of fusion-fission hybrid reactor for electric power generation by directly loading natural or depleted uranium if an ITER-scale tokamak fusion neutron source is achievable.

Zhou, Z.; Yang, Y.; Xu, H.

2011-10-01

252

Estimating the neutrally buoyant energy density of a Rankine-cycle/fuel-cell underwater propulsion system  

NASA Astrophysics Data System (ADS)

A unique requirement of underwater vehicles' power/energy systems is that they remain neutrally buoyant over the course of a mission. Previous work published in the Journal of Power Sources reported gross as opposed to neutrally-buoyant energy densities of an integrated solid oxide fuel cell/Rankine-cycle based power system based on the exothermic reaction of aluminum with seawater. This paper corrects this shortcoming by presenting a model for estimating system mass and using it to update the key findings of the original paper in the context of the neutral buoyancy requirement. It also presents an expanded sensitivity analysis to illustrate the influence of various design and modeling assumptions. While energy density is very sensitive to turbine efficiency (sensitivity coefficient in excess of 0.60), it is relatively insensitive to all other major design parameters (sensitivity coefficients < 0.15) like compressor efficiency, inlet water temperature, scaling methodology, etc. The neutral buoyancy requirement introduces a significant (?15%) energy density penalty but overall the system still appears to offer factors of five to eight improvements in energy density (i.e., vehicle range/endurance) over present battery-based technologies.

Waters, Daniel F.; Cadou, Christopher P.

2014-02-01

253

Stoichiometry in producer-grazer systems: linking energy flow with element cycling.  

PubMed

All organisms are composed of multiple chemical elements such as carbon, nitrogen and phosphorus. While energy flow and element cycling are two fundamental and unifying principles in ecosystem theory, population models usually ignore the latter. Such models implicitly assume chemical homogeneity of all trophic levels by concentrating on a single constituent, generally an equivalent of energy. In this paper, we examine ramifications of an explicit assumption that both producer and grazer are composed of two essential elements: carbon and phosphorous. Using stoichiometric principles, we construct a two-dimensional Lotka-Volterra type model that incorporates chemical heterogeneity of the first two trophic levels of a food chain. The analysis shows that indirect competition between two populations for phosphorus can shift predator-prey interactions from a (+, -) type to an unusual (-, -) class. This leads to complex dynamics with multiple positive equilibria, where bistability and deterministic extinction of the grazer are possible. We derive simple graphical tests for the local stability of all equilibria and show that system dynamics are confined to a bounded region. Numerical simulations supported by qualitative analysis reveal that Rosenzweig's paradox of enrichment holds only in the part of the phase plane where the grazer is energy limited; a new phenomenon, the paradox of energy enrichment, arises in the other part, where the grazer is phosphorus limited. A bifurcation diagram shows that energy enrichment of producer-grazer systems differs radically from nutrient enrichment. Hence, expressing producer-grazer interactions in stoichiometrically realistic terms reveals qualitatively new dynamical behavior. PMID:11127517

Loladze, I; Kuang, Y; Elser, J J

2000-11-01

254

LIFE CYCLE DESIGN OF AMORPHOUS SILICON PHOTOVOLTAIC MODULES  

EPA Science Inventory

The life cycle design framework was applied to photovoltaic module design. The primary objective of this project was to develop and evaluate design metrics for assessing and guiding the Improvement of PV product systems. Two metrics were used to assess life cycle energy perform...

255

Dual energy micro-CT imaging of radiation-induced vascular changes in primary mouse sarcomas  

PubMed Central

Purpose To evaluate the effects of radiation therapy on primary tumor vasculature using dual energy (DE) micro-computed tomography (micro-CT). Methods and Materials The Cre-loxP system was used to generate primary sarcomas with mutant Kras and p53. Unirradiated tumors were compared to tumors irradiated with 20 Gy. A long-circulating PEGylated liposomal-iodinated contrast agent was administered one day after treatment, and mice were imaged immediately after injection (day 1) and three days later (day 4) using DE micro-CT. CT-derived tumor sizes were used to assess tumor growth. After DE decomposition, iodine maps were used to assess tumor fractional blood volume (FBV) at day 1 and tumor vascular permeability at day 4. For comparison, tumor vascularity and vascular permeability were also evaluated histologically using CD31 immunofluorescence and fluorescently-labeled dextrans. Results Radiation treatment significantly decreased tumor growth (P<0.05). There was a positive correlation between CT-measurement of tumor FBV and extravasated iodine with microvascular density (MVD) (R2=0.53) and dextran accumulation (R2=0.63), respectively. Despite no change in MVD measured by histology, tumor FBV significantly increased after irradiation as measured by DE micro-CT (0.070 vs. 0.091, P<0.05). Both dextran and liposomal-iodine accumulation in tumors increased significantly after irradiation with dextran fractional area increasing 4.2-fold and liposomal-iodine concentration increasing 3.0-fold. Conclusions DE micro-CT is an effective tool for non-invasive assessment of vascular changes in primary tumors. Tumor blood volume and vascular permeability increased after a single therapeutic dose of radiation treatment. PMID:23122984

Moding, Everett J.; Clark, Darin P.; Qi, Yi; Li, Yifan; Ma, Yan; Ghaghada, Ketan; Johnson, G. Allan; Kirsch, David G.; Badea, Cristian T.

2013-01-01

256

The energy of the ocean thermal resource and the second-law efficiency of idealized ocean thermal energy conversion power cycles  

Microsoft Academic Search

A formula is developed to compute the maximum amount of work which can be extracted from a given combined mass of warm and cold ocean water (a quantity called the energy of the ocean thermal resources). Second it compares the second-law efficiencies of various proposed ocean thermal energy conversion power cycles to determine which best utilizes the energy of the

D. H. Johnson

1982-01-01

257

A novel thermally biased mechanical energy conversion cycle Ian M. McKinley, Sam Goljahi, Christopher S. Lynch, and Laurent Pilona)  

E-print Network

, or strains can also be harvested.6 Methods for direct mechanical to electrical energy conversion include) This paper demonstrates a new power cycle for direct conversion of mechanical energy into electrical energyA novel thermally biased mechanical energy conversion cycle Ian M. McKinley, Sam Goljahi

Pilon, Laurent

258

The energy of the ocean thermal resource and the second-law efficiency of idealized ocean thermal energy conversion power cycles  

NASA Astrophysics Data System (ADS)

A formula is developed to compute the maximum amount of work which can be extracted from a given combined mass of warm and cold ocean water (a quantity called the energy of the ocean thermal resources). Second it compares the second-law efficiencies of various proposed ocean thermal energy conversion power cycles to determine which best utilizes the energy of the ocean thermal resource. The second-law efficiencies of the multicomponent working fluid cycle, the Beck cycle, and the open and closed single- and multiple-stage Rankine cycles are compared. These types of OTEC power plants are analyzed in a consistent manner which assumes that all deviations from a plant making use of all the energy (one with a second-law efficiency of 100%) occurs because of irreversible transfer of heat across a finite temperature difference. Conversion of thermal energy to other forms is assumed to occur reversibly. The comparison of second-law efficiencies of various OTEC power cycles shows that the multistage Rankine open cycle with just three stages has the potential of best using the energy of the ocean thermal resource.

Johnson, D. H.

1982-09-01

259

Life-Cycle Assessment of Energy Use and Greenhouse Gas Emissions of Soybean-Derived Biodiesel and Renewable Fuels  

Microsoft Academic Search

In this study, we used Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model to assess the life-cycle energy and greenhouse gas (GHG) emission impacts of four soybean-derived fuels: biodiesel fuel produced via transesterification, two renewable diesel fuels (I and II) produced from different hydrogenation processes, and renewable gasoline produced from catalytic cracking. Five approaches

Hong Huo; Michael Wang; Cary Bloyd; Vicky Putsche

2009-01-01

260

Arabidopsis Mutants Define a Central Role for the Xanthophyll Cycle in the Regulation of Photosynthetic Energy Conversion  

Microsoft Academic Search

A conserved regulatory mechanism protects plants against the potentially damaging effects of excessive light. Nearly all photosynthetic eukaryotes are able to dissipate excess absorbed light energy in a process that involves xanthophyll pigments. To dissect the role of xanthophylls in photoprotective energy dissipation in vivo, we isolated Arabidopsis xanthophyll cycle mutants by screening for altered nonphotochemical quenching of chlorophyll fluorescence.

Krishna K. Niyogi; Arthur R. Grossman; Olle Björkman

1998-01-01

261

Planning for hybrid-cycle OTEC experiments using the HMTSTA test facility at the Natural Energy Laboratory of Hawaii  

NASA Astrophysics Data System (ADS)

The U.S. Department of Energy has built an experimental apparatus for studying the open-cycle Ocean Thermal Energy Conversion (OC-OTEC) system. Experiments using warm and cold seawater are currently underway to validate the performance predictions for an OC-TEC flash evaporator, surface condenser, and direct-contact condenser. The hybrid cycle is another OTEC option that produces both power and desalinated water, it is comparable in capital cost to OC-OTEC, and it eliminates the problems associated with the large steam turbine. Means are presented or modifying the existing apparatus to conduct similar experiments on hybrid-cycle OTEC heat exchangers. These data are required to validate predictive methods of the components and for the system integration that were identified in an earlier study of hybrid-cycle OTEC power plants.

Panchal, C.; Rabas, T.; Genens, L.

262

Life-cycle energy and greenhouse gas emission impacts of different corn ethanol plant types.  

SciTech Connect

Since the United States began a program to develop ethanol as a transportation fuel, its use has increased from 175 million gallons in 1980 to 4.9 billion gallons in 2006. Virtually all of the ethanol used for transportation has been produced from corn. During the period of fuel ethanol growth, corn farming productivity has increased dramatically, and energy use in ethanol plants has been reduced by almost by half. The majority of corn ethanol plants are powered by natural gas. However, as natural gas prices have skyrocketed over the last several years, efforts have been made to further reduce the energy used in ethanol plants or to switch from natural gas to other fuels, such as coal and wood chips. In this paper, we examine nine corn ethanol plant types--categorized according to the type of process fuels employed, use of combined heat and power, and production of wet distiller grains and solubles. We found that these ethanol plant types can have distinctly different energy and greenhouse gas emission effects on a full fuel-cycle basis. In particular, greenhouse gas emission impacts can vary significantly--from a 3% increase if coal is the process fuel to a 52% reduction if wood chips are used. Our results show that, in order to achieve energy and greenhouse gas emission benefits, researchers need to closely examine and differentiate among the types of plants used to produce corn ethanol so that corn ethanol production would move towards a more sustainable path.

Wang, M.; Wu, M.; Huo, H.; Energy Systems

2007-04-01

263

Renewable Energy from Willow Biomass Crops: Life Cycle Energy, Environmental and Economic Performance  

Microsoft Academic Search

Short-rotation woody crops (SRWC) along with other woody biomass feedstocks will play a significant role in a more secure and sustainable energy future for the United States and around the world. In temperate regions, shrub willows are being developed as a SRWC because of their potential for high biomass production in short time periods, ease of vegetative propagation, broad genetic

Gregory A. Keoleian; Timothy A. Volk

2005-01-01

264

FEASIBILITY OF HYDROGEN PRODUCTION USING LASER INERTIAL FUSION AS THE PRIMARY ENERGY SOURCE  

SciTech Connect

The High Average Power Laser (HAPL) program is developing technology for Laser IFE with the goal of producing electricity from the heat generated by the implosion of deuterium-tritium (DT) targets. Alternatively, the Laser IFE device could be coupled to a hydrogen generation system where the heat would be used as input to a water-splitting process to produce hydrogen and oxygen. The production of hydrogen in addition to electricity would allow fusion energy plants to address a much wider segment of energy needs, including transportation. Water-splitting processes involving direct and hybrid thermochemical cycles and high temperature electrolysis are currently being developed as means to produce hydrogen from high temperature nuclear fission reactors and solar central receivers. This paper explores the feasibility of this concept for integration with a Laser IFE plant, and it looks at potential modifications to make this approach more attractive. Of particular interest are: (1) the determination of the advantages of Laser IFE hydrogen production compared to other hydrogen production concepts, and (2) whether a facility of the size of FTF would be suitable for hydrogen production.

Gorensek, M

2006-11-03

265

Life-cycle cost economic optimization of insulation, infiltration, and solar aperture in energy-efficient houses  

Microsoft Academic Search

A total life-cycle cost economic optimization technique has been applied to the design of energy efficient residential structures in Madison, WI, and Albuquerque, NM, and building designs having a least life-cycle cost to build and heat have been determined. Economically optimum combinations of insulation values and south-facing glass areas were found for several design options at each location: high and

1983-01-01

266

Cell type and transfection reagent-dependent effects on viability, cell content, cell cycle and inflammation of RNAi in human primary mesenchymal cells.  

PubMed

The application of RNA interference (RNAi) has great therapeutic potential for degenerative diseases of cartilaginous tissues by means of fine tuning the phenotype of cells used for regeneration. However, possible non-specific effects of transfection per se might be relevant for future clinical application. In the current study, we selected two synthetic transfection reagents, a cationic lipid-based commercial reagent Lipofectamine RNAiMAX and polyethylenimine (PEI), and two naturally-derived transfection reagents, namely the polysaccharides chitosan (98% deacetylation) and hyaluronic acid (20% amidation), for siRNA delivery into primary mesenchymal cells including nucleus pulposus cells, articular chondrocytes and mesenchymal stem cells (MSCs). Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as an endogenous model gene to evaluate the extent of silencing by 20 nM or 200 nM siRNA at day 3 and day 6 post-transfection. In addition to silencing efficiency, non-specific effects such as cytotoxicity, change in DNA content and differentiation potential of cells were evaluated. Among the four transfection reagents, the commercial liposome-based agent was the most efficient reagent for siRNA delivery at 20 nM siRNA, followed by chitosan. Transfection using cationic liposomes, chitosan and PEI showed some decrease in viability and DNA content to varying degrees that was dependent on the siRNA dose and cell type evaluated, but independent of GAPDH knockdown. Some effects on DNA content were not accompanied by concomitant changes in viability. However, changes in expression of marker genes for cell cycle inhibition or progression, such as p21 and PCNA, could not explain the changes in DNA content. Interestingly, aspecific upregulation of GAPDH activity was found, which was limited to cartilaginous cells. In conclusion, non-specific effects should not be overlooked in the application of RNAi for mesenchymal cell transfection and may need to be overcome for its effective therapeutic application. PMID:24345796

Yang, Hsiao-yin; Vonk, Lucienne A; Licht, Ruud; van Boxtel, Antonetta M G; Bekkers, Joris E J; Kragten, Angela H M; Hein, San; Varghese, Oommen P; Howard, Kenneth A; Öner, F Cumhur; Dhert, Wouter J A; Creemers, Laura B

2014-03-12

267

The sustainable water-energy nexus: Life-cycle impacts and feasibility of regional energy and water supply scenarios  

NASA Astrophysics Data System (ADS)

Water and energy are critical, interdependent, and regional resources, and effective planning and policies around which sources to use requires combining information on environmental impacts, cost, and availability. Questions around shifting energy and water sources towards more renewable options, as well as the potential role of natural gas from shale formations are under intense discussion. Decisions on these issues will be made in the shadow of climate change, which will both impact and be impacted by energy and water supplies. This work developed a model for calculating the life-cycle environmental impacts of regional energy and water supply scenarios (REWSS). The model was used to discuss future energy pathways in Pennsylvania, future electricity impacts in Brazil, and future water pathways in Arizona. To examine energy in Pennsylvania, this work also developed the first process-based life-cycle assessment (LCA) of shale gas, focusing on greenhouse gas (GHG) emissions, energy consumption, and water consumption. This LCA confirmed results that shale gas is similar to conventional gas in GHG emissions, though potentially has a lower net energy due to a wide range of production rates for wells. Brazil's electricity-related impacts will rise as development continues. GHG emissions are shown to double by 2020 due to expanded natural gas (NG) and coal usage, with a rise of 390% by 2040 posssible with tropical hydropower reservoirs. While uncertainty around reservoir impacts is large, Brazil's low GHG emissions intensity and future carbon emissions targets are threatened by likely electricity scenarios. Pennsylvania's energy-related impacts are likely to hinge on whether NG is used as a replacement for coal, allowing GHG emissions to drop and then plateau at 93% of 2010 values; or as a transition fuel to expanded renewable energy sources, showing a steady decrease to 86% in 2035. Increased use of biofuels will dominate land occupation and may dominate water consumption impacts, depending on irrigation -- water consumption for energy rises from 7% to 18% under the base case. Arizona is further from major shale basins, but aims to reduce unsustainable groundwater usage. Desalination by itself will increase annual impacts by at least 2% in all impact categories by 2035, and prioritizing renewable energy sources along with desalination was found to lower GHGs by 1% from BAU, but increase 2035 impacts in all other categories by at least 10% from new construction or operation. In both PA and AZ, changes in impacts and shifting sources have interconnected tradeoffs, making the water-enegy nexus a key part of managing environmental problems such as climate change. Future energy and water supplies are also likely to show higher interdependencies, which may or may not improve regional sustainability. This work offers a way to combine four important sets of information to enable the generation of answers to key regional planning questions around these two key resources.

Dale, Alexander T.

268

The advanced fuel cycle facility (AFCF) role in the global nuclear energy partnership  

SciTech Connect

The Global Nuclear Energy Partnership (GNEP), launched in February, 2006, proposes to introduce used nuclear fuel recycling in the United States with improved proliferation-resistance and a more effective waste management approach. This program is evaluating ways to close the fuel cycle in a manner that builds on recent laboratory breakthroughs in U.S. national laboratories and draws on international and industry partnerships. Central to moving this advanced fuel recycling technology from the laboratory to commercial implementation is a flexible research, development and demonstration facility, called the Advanced Fuel Cycle Facility (AFCF). The AFCF was introduced as one of three projects under GNEP and will provide the U.S. with the capabilities to evaluate technologies that separate used fuel into reusable material and waste in a proliferation-resistant manner. The separations technology demonstration capability is coupled with a remote transmutation fuel fabrication demonstration capability in an integrated manner that demonstrates advanced safeguard technologies. This paper will discuss the key features of AFCF and its support of the GNEP objectives. (author)

Griffith, Andrew [U.S. Department of Energy, 1000 Independence Ave., SW, Washington, DC 20858 (United States)

2007-07-01

269

Synchronous timing of multi-energy fast beam extraction during a single AGS cycle  

SciTech Connect

Synchronous triggering of fast beams is required because the field of Kicker Magnets must rise within the open space between one beam bunch and the next. Within the Brookhaven AGS, Fast Extracted Beam (FEB) triggering combines nominal timing, based on beam energy with bunch-to-bunch synchronization, based on the accelerating rf waveform. During beam acceleration, a single bunch is extracted at 22 GeV/c and within the same AGS cycle, the remaining eleven bunches are extracted at 28.4 GeV/c. When the single bunch is extracted, a ''hole'', which is left in the remaining circulating beam, can appear in random locations within the second extraction during successive AGS cycles. To overcome this problem, a synchronous rf/12 counting scheme and logic circuitry are used to keep track of the bunch positions relative to each other, and to place the ''hole'' in any desired location within the second extraction. The rf/12 signal is used also to synchronize experimenters triggers.

Gabusi, J.; Naase, S.

1985-01-01

270

Technology for Brayton-cycle space powerplants using solar and nuclear energy  

SciTech Connect

Brayton-cycle gas turbines have the potential to use either solar heat or nuclear reactors to generate from tens of kilowatts to tens of megawatts of power in space, all this from a single technology for the power-generating system. Their development for solar-energy dynamic power generation for the space station could be the first step in an evolution of such powerplants for a very wide range of applications. At the low power level of only 10 kWe, a power-generating system has already demonstrated overall efficiency of 0.29 and operated for 38,000 hr. Tests of improved components show that, if installed in the power-generating system, these components would raise that efficiency to 0.32; this efficiency is twice that so far demonstrated by any alternate concept, a characteristic especially important for solar power systems. Because of this high efficiency, solar-heat Brayton-cycle power generators offer the potential to increase power per unit of solar-collector area to levels exceeding four times that from photovoltaic powerplants based on present technology for silicon solar cells. For the heat source, paraboloidal mirrors have been assembled from sectors here on Earth. One mirror, 1.5-m diameter, had a standard error for its surface of only 1 arc-min and a specific mass of only 1.3 kg/m 2. A heavier mirror (nearly 5 kg/m{sup 2}), assembled from 12 sectors, had a standard surface error of 3 arc-min but was 6 m in diameter. Either of these mirrors is sufficiently accurate for use with the Brayton cycle, but the techniques for actually assembling large mirrors in space must yet be worked out. For use during the shadow period of a low Earth orbit (LEO), heat could be stored in LiF, a salt that melts at 1121 K (1558{degrees}F) and whose latent heat of fusion exceeds 1 MJ/kg. Because of the prior experience with its fabrication and of its tolerance of the thermal cycling in LEO, Nb-1Zr was selected to contain the LiF.

English, R.E.

1986-02-01

271

Life cycle energy, environment and economic assessment of soybean-based biodiesel as an alternative automotive fuel in China  

Microsoft Academic Search

Life cycle energy, environment and economic assessment for conventional diesel (CD) and soybean-based biodiesel (SB) in China was carried out in this paper. The results of the assessment have shown that compared with CD, SB has similar source-to-tank (StT) total energy consumption, 76% lower StT fossil energy consumption, 79% higher source-to-wheel (StW) nitrogen oxides (NOX) emissions, 31%, 44%, 36%, 29%,

Zhiyuan Hu; Piqiang Tan; Xiaoyu Yan; Diming Lou

2008-01-01

272

Material and energy recovery in integrated waste management systems: A life-cycle costing approach  

SciTech Connect

Highlights: > The study aims at assessing economic performance of alternative scenarios of MSW. > The approach is the life-cycle costing (LCC). > Waste technologies must be considered as complementary into an integrated strategy. - Abstract: A critical assumption of studies assessing comparatively waste management options concerns the constant average cost for selective collection regardless the source separation level (SSL) reached, and the neglect of the mass constraint. The present study compares alternative waste management scenarios through the development of a desktop model that tries to remove the above assumption. Several alternative scenarios based on different combinations of energy and materials recovery are applied to two imaginary areas modelled in order to represent a typical Northern Italian setting. External costs and benefits implied by scenarios are also considered. Scenarios are compared on the base of the full cost for treating the total waste generated in the area. The model investigates the factors that influence the relative convenience of alternative scenarios.

Massarutto, Antonio [University of Udine, Udine (Italy); IEFE, Bocconi University, Milan (Italy); Carli, Alessandro de, E-mail: alessandro.decarli@unibocconi.it [IEFE, Bocconi University, Milan (Italy); Graffi, Matteo [University of Udine, Udine (Italy); IEFE, Bocconi University, Milan (Italy)

2011-09-15

273

Study of hydraulic air compression for Ocean Thermal Energy Conversion open-cycle application  

NASA Astrophysics Data System (ADS)

A hydraulic air compressor, which requires no mechanical moving parts and operates in a nearly isothermal mode, can be an alternative for the noncondensible gas disposal of an Ocean Thermal Energy Conversion (OTEC) open-cycle power system. The compressor requires only a downward flow of water to accomplish air compression. An air compressor test loop was assembled and operated to obtain test data that would lead to the design of an OTEC hydraulic air compressor. A one dimensional, hydraulic gas compressor, computer model was employed to simulate the laboratory experiments, and it was tuned to fit the test results. A sensitivity study that shows the effects of various parameters on the applied head of the hydraulic air compression is presented.

Golshani, A.; Chen, F. C.

1983-01-01

274

Seawater test results of Open-Cycle Ocean Thermal Energy Conversion (OC-OTEC) components  

NASA Astrophysics Data System (ADS)

Key components of open-cycle ocean thermal energy conversion systems- the flash evaporator, mist eliminator, passive predeaerator, two surface condenser stages, and two direct-contact condenser stages- have been tested using seawater. These components operate at lower steam pressures and higher inlet noncondensable gas concentrations than do conventional power plant heat exchangers. The rate of heat exchanged between the evaporator and the condenser is on the order of 1.25MW-thermal, requiring a warm seawater flow of about 0.1 cu m/s; the cold seawater flow is on the order of half the warm water flow. In addition to characterizing the performance of the various components, the system has produced potable water from condensation of the steam produced in the evaporator. The information obtained in these tests is being used to design a larger scale experiment in which net power production is expected to be demonstrate for the first time using OC-OTEC technology.

Zangrando, F.; Bharathan, D.; Link, H.; Panchal, C. B.

275

Thermodynamic analysis of a Rankine cycle powered vapor compression ice maker using solar energy.  

PubMed

To develop the organic Rankine-vapor compression ice maker driven by solar energy, a thermodynamic model was developed and the effects of generation temperature, condensation temperature, and working fluid types on the system performance were analyzed. The results show that the cooling power per square meter collector and ice production per square meter collector per day depend largely on generation temperature and condensation temperature and they increase firstly and then decrease with increasing generation temperature. For every working fluid there is an optimal generation temperature at which organic Rankine efficiency achieves the maximum value. The cooling power per square meter collector and ice production per square meter collector per day are, respectively, 126.44 W m(-2) and 7.61 kg m(-2) day(-1) at the generation temperature of 140 °C for working fluid of R245fa, which demonstrates the feasibility of organic Rankine cycle powered vapor compression ice maker. PMID:25202735

Hu, Bing; Bu, Xianbiao; Ma, Weibin

2014-01-01

276

Search for primary photons and neutrinos in the ultra-high energy cosmic rays with the Pierre Auger Observatory  

NASA Astrophysics Data System (ADS)

Along with primary protons and nuclei most of the scenarios of the origin of cosmic rays predict fluxes of photons and neutrinos at the highest energies. Thanks to the huge collection area and the hybrid design, combining ground array and fluorescence detection techniques, the Pierre Auger Observatory is a unique tool to search for primary photons and neutrinos in ultra-high energy cosmic rays. Implications of these searches extend from astrophysics to fundamental and particle physics. Current results and future perspectives are reported.

Scherini, V.; Pierre Auger Collaboration

2011-03-01

277

Measurement of Changes in High-Energy Phosphates in the Cardiac Cycle by Using Gated 31P Nuclear Magnetic Resonance  

NASA Astrophysics Data System (ADS)

Levels of the high-energy phosphate-containing compounds, ATP and creatine phosphate, and of inorganic phosphate (Pi) were measured as a function of position in the cardiac cycle. Measurements were made on isolated, perfused, working rat hearts through the use of gated 31P nuclear magnetic resonance spectroscopy. Levels of ATP and creatine phosphate were found to vary during the cardiac cycle and were maximal at minimal aortic pressure and minimal at maximal aortic pressure. Pi varied inversely with the high-energy phosphates.

Fossel, Eric T.; Morgan, Howard E.; Ingwall, Joanne S.

1980-06-01

278

Combined heat and power systems for commercial buildings: investigating cost, emissions, and primary energy reduction based on system components  

NASA Astrophysics Data System (ADS)

Combined heat and power (CHP) systems produce electricity and useful heat from fuel. When power is produced near a building which consumes power, transmission losses are averted, and heat which is a byproduct of power production may be useful to the building. That thermal energy can be used for hot water or space heating, among other applications. This dissertation focuses on CHP systems using natural gas, a common fuel, and systems serving commercial buildings in the United States. First, the necessary price difference between purchased electricity and purchased fuel is analyzed in terms of the efficiencies of system components by comparing CHP with a conventional separate heat and power (SHP) configuration, where power is purchased from the electrical grid and heat is provided by a gas boiler. Similarly, the relationship between CDE due to electricity purchases and due to fuel purchases is analyzed as well as the relationship between primary energy conversion factors for electricity and fuel. The primary energy conversion factor indicates the quantity of source energy necessary to produce the energy purchased at the site. Next, greenhouse gas emissions are investigated for a variety of commercial buildings using CHP or SHP. The relationship between the magnitude of the reduction in emissions and the parameters of the CHP system is explored. The cost savings and reduction in primary energy consumption are evaluated for the same buildings. Finally, a CHP system is analyzed with the addition of a thermal energy storage (TES) component, which can store excess thermal energy and deliver it later if necessary. The potential for CHP with TES to reduce cost, emissions, and primary energy consumption is investigated for a variety of buildings. A case study is developed for one building for which TES does provide additional benefits over a CHP system alone, and the requirements for a water tank TES device are examined.

Smith, Amanda D.

279

On the Effects of Node Density and Duty Cycle on Energy Efficiency in Underwater Networks  

E-print Network

the transmitter and the receiver, the nodes set a waiting time for DATA transmission in order to reduce the number for the rest of the cycle time. The nodes start their cycles at arbitrary times, so that global synchronization a duty cycle is to reduce the effective node density. This effective density can be used to set the power

Stojanovic, Milica

280

Control and Optimization of Vapor Compression Cycles Using Recursive Least Squares Estimation  

E-print Network

Vapor compression cycles are the primary method by which refrigeration and air-conditioning systems operate, and thus constitute a significant portion of commercial and residential building energy consumption. This thesis presents a data...

Rani, Avinash

2012-10-19

281

Total energy cycle assessment of electric and conventional vehicles: an energy and environmental analysis. Volume 2: appendices A-D to technical report  

SciTech Connect

This report compares the energy use, oil use and emissions of electric vehicles (EVs) with those of conventional, gasoline- powered vehicles (CVs) over the total life cycle of the vehicles. The various stages included in the vehicles` life cycles include vehicle manufacture, fuel production, and vehicle operation. Disposal is not included. An inventory of the air emissions associated with each stage of the life cycle is estimated. Water pollutants and solid wastes are reported for individual processes, but no comprehensive inventory is developed. Volume II contains additional details on the vehicle, utility, and materials analyses and discusses several details of the methodology.

NONE

1998-01-01

282

Progress in Photovoltaics Research and Applications, 14:179-190, 2006 Energy Pay-Back and Life Cycle CO2 Emissions of the BOS in an  

E-print Network

with sensitivity- and data-uncertainty analyses. Key Words: PV plant; balance of system; life cycle assessment such savings and lower emissions is timely. Previous life-cycle assessments of field and rooftop PV systems,2,3,4 These assessments were based on a single plant, the Serre plant in Italy, whose BOS life-cycle energy was estimated

283

Revised Energy Spectra for Primary Elements (H - Si) above 50 GeV from the ATIC-2 Science Flight  

NASA Astrophysics Data System (ADS)

The Advanced Thin Ionization Calorimeter (ATIC) long duration balloon experiment had a successful science flight accumulating 18 days of data (12/02 - 1/03) during a single circumnavigation in Antarctica. ATIC measures the energy spectra of elements from H to Fe in primary cosmic rays using a fully active Bismuth Germanate calorimeter preceded by a carbon target, with embedded scintillator hodoscopes, and a silicon matrix charge detector at the top. Preliminary results from ATIC have been reported in previous conferences. The revised results reported here are derived from a new analysis of the data with improved charge resolution, lower background and revised energy calibration. The raw energy deposit spectra are de-convolved into primary energy spectra and extrapolated to the top of the atmosphere. We compare these revised results to previous data and comment upon the astrophysical interpretation of the data.

Wefel, J. P.; Adams, J. H., Jr.; Ahn, H. S.; et al.

284

Revised Energy Spectra for Primary Elements, H - Si, above 50 GeV from the ATIC-2 Science Flight  

NASA Technical Reports Server (NTRS)

The Advanced Thin Ionization Calorimeter (ATIC) long duration balloon experiment had a successful science flight accumulating 18 days of data (12/02 - 1/03) during a single circumnavigation in Antarctica. ATIC measures the energy spectra of elements from H to Fe in primary cosmic rays using a fully active Bismuth Germanate calorimeter preceded by a carbon target, with embedded scintillator hodoscopes, and a silicon matrix charge detector at the top. Preliminary results from ATIC have been reported in previous conferences. The revised results reported here are derived from a new analysis of the data with improved charge resolution, lower background and revised energy calibration. The raw energy deposit spectra are de-convolved into primary energy spectra and extrapolated to the top of the atmosphere. We compare these revised results to previous data and comment upon the astrophysical interpretation of the results.

Wefel, J. P.; Adams, J. H., Jr.; Ahn, H. S.; Bashindzhagyan, G. L.; Chang, J.; Christl, M.; Fazely, A. R.; Ganel, O.; Gunashingha, R. M.; Guzik, T. G.; Isbert, J.; Kim, K. C.; Kouznetsov, E. N.; Panasyuk, M. I.; Panov, A. D.; Schmidt, W. K. H.; Seo, E. S.; Sokolskaya, N. V.; Watts, J. W.; Wu, J.; Zatsepin, V. I.

2007-01-01

285

A Practical Approach to a Closed Nuclear Fuel Cycle and Sustained Nuclear Energy - 12383  

SciTech Connect

Recent systems analysis studies at Oak Ridge National Laboratory (ORNL) have shown that sufficient information is available from previous research and development (R and D), industrial experience, and current studies to make rational decisions on a practical approach to a closed nuclear fuel cycle in the United States. These studies show that a near-term decision is needed to recycle used nuclear fuel (UNF) in the United States, to encourage public recognition that a practical solution to disposal of nuclear energy wastes, primarily UNF, is achievable, and to ensure a focus on essential near-term actions and future R and D. Recognition of the importance of time factors is essential, including the multi-decade time period required to implement industrial-scale fuel recycle at the capacity needed, and the effects of radioactive decay on proliferation resistance, recycling complexity, radioactive emissions, and high-level-waste storage, disposal form development, and eventual emplacement in a geologic repository. Analysis of time factors led to identification of the benefits of processing older fuel and an 'optimum decay storage time'. Further benefits of focused R and D can ensure more complete recycling of UNF components and minimize wastes requiring disposal. Analysis of recycling costs and nonproliferation requirements, which are often cited as reasons for delaying a decision to recycle, shows that (1) the differences in costs of nuclear energy with open or closed fuel cycles are insignificant and (2) nonproliferation requirements can be met by a combination of 'safeguards-by-design' co-location of back-end fuel cycle facilities, and applied engineered safeguards and monitoring. The study shows why different methods of separating and recycling used fuel components do not have a significant effect on nonproliferation requirements and can be selected on other bases, such as process efficiency, maturity, and cost-effectiveness. Finally, the study concludes that continued storage of UNF without a decision to recycle is not a solution to the problem of nuclear waste disposal, but can be a deterrent to public confidence in nuclear energy. In summary, our studies have shown, in contrast to findings of the more prominent studies, that today we do have sufficient knowledge to make informed choices for the values and essential methods of UNF recycling, based on previous research, industrial experience, and current analyses. We have shown the significant importance of time factors, including the benefits of an optimum decay storage time on deploying effective nonproliferation safeguards, enabling reduced recycling complexity and environmental emissions, and optimizing waste management and disposal. Together with the multi-decade time required to implement industrial-scale UNF recycle at the capacity needed to match generation rate, our conclusion is that a near-term decision to recycle as many UNF components as possible is vitally needed. Further indecision and procrastination can lead to a loss of public confidence and favorable perception of nuclear energy. With no near-term decision, the path forward for UNF disposal will remain uncertain, with many diverse technologies being considered and no possible focus on a practical solution to the problem. However, a near-term decision to recycle UNF fuel and to take advantage of processing UNF and surface storing HLW, together with development and incorporation of more-complete recycling of UNF components, can provide the focus needed for a practical solution to the problem of nuclear waste disposal. (authors)

Collins, Emory D.; Del Cul, Guillermo D.; Spencer, Barry B.; Williams, Kent A. [Oak Ridge National Laboratory, P.O. Box 2008, MS-6152, Oak Ridge TN 37831 (United States)

2012-07-01

286

Annual-cycle thermal energy storage for a community solar system: details of a sensitivity analysis  

SciTech Connect

This report presents results and conclusions of a simulation and sensitivity analysis of community-sized, annual-cycle thermal-energy-storage (ACTES) solar energy systems. The analysis which is based on an hourly simulation is used to (1) size systems in 10 locations, (2) identify critical design parameters, and (3) provide a basic conceptual approach for future studies and designs. This research is a forerunner to an economic analysis of this particular system (based on large constructed tanks) and a general analysis of the value of ACTES technologies for solar applications. A total of 440 systems were sized for 10 locations in the United States. Three different building types and four different community sizes were modeled. All designs used each of two collector types at each of two different tilt angles. Two linear relationships were derived which simplify system sizing. The average ambient temperature is used to determine average yearly collector efficiency. This parameter combined with estimates of space/DHW loads, storage/distribution losses, and total yearly insolation per square meter allows estimation of collector area. Storage size can be estimated from the winter net load which is based on space and DHW loads, storage and distribution losses, and collector solar heat gain for the winter months.

Baylin, F.; Monte, R.; Sillman, S.

1980-07-01

287

Bioenergy co-products derived from microalgae biomass via thermochemical conversion--life cycle energy balances and CO2 emissions.  

PubMed

An investigation of the potential to efficiently convert lipid-depleted residual microalgae biomass using thermochemical (gasification at 850 °C, pyrolysis at 550 °C, and torrefaction at 300 °C) processes to produce bioenergy derivatives was made. Energy indicators are established to account for the amount of energy inputs that have to be supplied to the system in order to gain 1 MJ of bio-energy output. The paper seeks to address the difference between net energy input-output balances based on a life cycle approach, from "cradle-to-bioenergy co-products", vs. thermochemical processes alone. The experimental results showed the lowest results of Net Energy Balances (NEB) to be 0.57 MJ/MJ bio-oil via pyrolysis, and highest, 6.48 MJ/MJ for gas derived via torrefaction. With the complete life cycle process chain factored in, the energy balances of NEBLCA increased to 1.67 MJ/MJ (bio-oil) and 7.01 MJ/MJ (gas). Energy efficiencies and the life cycle CO2 emissions were also calculated. PMID:23810951

Khoo, H H; Koh, C Y; Shaik, M S; Sharratt, P N

2013-09-01

288

Energy Spectra, Composition, and Other Properties of Ground-Level Events During Solar Cycle 23  

NASA Astrophysics Data System (ADS)

We report spacecraft measurements of the energy spectra of solar protons and other solar energetic particle properties during the 16 Ground Level Events (GLEs) of Solar Cycle 23. The measurements were made by eight instruments on the ACE, GOES, SAMPEX, and STEREO spacecraft and extend from ˜0.1 to ˜500-700 MeV. All of the proton spectra exhibit spectral breaks at energies ranging from ˜2 to ˜46 MeV and all are well fit by a double power-law shape. A comparison of GLE events with a larger sample of other solar energetic particle (SEP) events shows that the typical spectral indices are harder in GLE events, with a mean slope of -3.18 at >40 MeV/nuc. In the energy range 45 to 80 MeV/nucleon about ˜50 % of GLE events have properties in common with impulsive 3He-rich SEP events, including enrichments in Ne/O, Fe/O, 22Ne/20Ne, and elevated mean charge states of Fe. These 3He-rich events contribute to the seed population accelerated by CME-driven shocks. An analysis is presented of whether highly-ionized Fe ions observed in five events could be due to electron stripping during shock acceleration in the low corona. Making use of stripping calculations by others and a coronal density model, we can account for events with mean Fe charge states of < Q Fe>?+20 if the acceleration starts at ˜1.24-1.6 solar radii, consistent with recent comparisons of CME trajectories and type-II radio bursts. In addition, we suggest that gradual stripping of remnant ions from earlier large SEP events may also contribute a highly-ionized suprathermal seed population. We also discuss how observed SEP spectral slopes relate to the energetics of particle acceleration in GLE and other large SEP events.

Mewaldt, R. A.; Looper, M. D.; Cohen, C. M. S.; Haggerty, D. K.; Labrador, A. W.; Leske, R. A.; Mason, G. M.; Mazur, J. E.; von Rosenvinge, T. T.

2012-10-01

289

Modeling energy flow and nutrient cycling in natural semiarid grassland ecosystems with the aid of thematic mapper data  

NASA Technical Reports Server (NTRS)

Energy flow and nutrient cycling were modeled as affected by herbivory on selected intensive sites along gradients of precipitation and soils, validating the model output by monitoring selected parameters with data derived from the Thematic Mapper (TM). Herbivore production was modeled along the gradient of soils and herbivory, and validated with data derived from TM in a spatial data base.

Lewis, James K.

1987-01-01

290

Students' Understanding of Energy Flow and Matter Cycling in the Context of the Food Chain, Photosynthesis, and Respiration  

ERIC Educational Resources Information Center

The research focus on children's science has recently shifted from separate concepts to more comprehensive and complex topics. This study addressed pupils' understanding of the complex topic of energy flow and matter cycling. A scoring system with three categories and six concepts was developed and used by four biology teachers to analyze 106…

Lin, Chen-Yung; Hu, Reping

2003-01-01

291

The storm tracks and the energy cycle of the Southern Hemisphere: sensitivity to sea-ice boundary conditions  

E-print Network

The storm tracks and the energy cycle of the Southern Hemisphere: sensitivity to sea-ice boundary. The eect of sea-ice on various aspects of the Southern Hemisphere (SH) extratropical climate is examined. Two simulations using the LMD GCM are performed: a control run with the observed sea-ice distribution

Paris-Sud XI, Université de

292

Transportation versus perishability in life cycle energy consumption: A case study of the temperature-controlled food product supply chain  

Microsoft Academic Search

Moving goods from the point of production to markets involves energy use and can have adverse environmental effects. But from the supply chain management perspective, the control of the supply chain, with short time cycles between production and sale to customer, can benefit the environment by closely tailoring production to consumption, and by minimizing the amount of “perishability” in the

Francis Vanek; Yao Sun

2008-01-01

293

Exergy of the ocean thermal resource and the second law efficiency of idealized ocean thermal energy conversion power cycles  

Microsoft Academic Search

A formula is developed to compute the maximum amount of work which can be extracted from a given combined mass of warm and cold ocean water (a quantity called the exergy of the ocean thermal resource). The second law efficiencies of various proposed ocean thermal energy conversion power cycles are compared to determine which best utilizes the exergy of the

D. H. Johnson

1982-01-01

294

High-Energy-Density, Low-Temperature Li/CFx Primary Cells  

NASA Technical Reports Server (NTRS)

High-energy-density primary (nonrechargeable) electrochemical cells capable of relatively high discharge currents at temperatures as low as -40 C have been developed through modification of the chemistry of commercial Li/CFx cells and batteries. The commercial Li/CFx units are not suitable for high-current and low-temperature applications because they are current limited and their maximum discharge rates decrease with decreasing temperature. The term "Li/CFx" refers to an anode made of lithium and a cathode made of a fluorinated carbonaceous material (typically graphite). In commercial cells, x typically ranges from 1.05 to 1.1. This cell composition makes it possible to attain specific energies up to 800 Wh/kg, but in order to prevent cell polarization and the consequent large loss of cell capacity, it is typically necessary to keep discharge currents below C/50 (where C is numerically equal to the current that, flowing during a charge or discharge time of one hour, would integrate to the nominal charge or discharge capacity of a cell). This limitation has been attributed to the low electronic conductivity of CFx for x approx. 1. To some extent, the limitation might be overcome by making cathodes thinner, and some battery manufacturers have obtained promising results using thin cathode structures in spiral configurations. The present approach includes not only making cathodes relatively thin [.2 mils (.0.051 mm)] but also using sub-fluorinated CFx cathode materials (x < 1) in conjunction with electrolytes formulated for use at low temperatures. The reason for choosing sub-fluorinated CFx cathode materials is that their electronic conductivities are high, relative to those for which x > 1. It was known from recent prior research that cells containing sub-fluorinated CFx cathodes (x between 0.33 and 0.66) are capable of retaining substantial portions of their nominal low-current specific energies when discharged at rates as high as 5C at room temperature. However, until experimental cells were fabricated following the present approach and tested, it was not known whether or to what extent low-temperature performance would be improved.

Whitacre, Jay; Bugga, Ratnakumar; Smart, Marshall; Prakash, G.; Yazami, Rachid

2007-01-01

295

A high-rate and long cycle life aqueous electrolyte battery for grid-scale energy storage.  

PubMed

New types of energy storage are needed in conjunction with the deployment of solar, wind and other volatile renewable energy sources and their integration with the electric grid. No existing energy storage technology can economically provide the power, cycle life and energy efficiency needed to respond to the costly short-term transients that arise from renewables and other aspects of grid operation. Here we demonstrate a new type of safe, fast, inexpensive, long-life aqueous electrolyte battery, which relies on the insertion of potassium ions into a copper hexacyanoferrate cathode and a novel activated carbon/polypyrrole hybrid anode. The cathode reacts rapidly with very little hysteresis. The hybrid anode uses an electrochemically active additive to tune its potential. This high-rate, high-efficiency cell has a 95% round-trip energy efficiency when cycled at a 5C rate, and a 79% energy efficiency at 50C. It also has zero-capacity loss after 1,000 deep-discharge cycles. PMID:23093186

Pasta, Mauro; Wessells, Colin D; Huggins, Robert A; Cui, Yi

2012-01-01

296

PSTAR: Primary and secondary terms analysis and renormalization: A unified approach to building energy simulations and short-term monitoring  

SciTech Connect

This report presents a unified method of hourly simulation of a building and analysis of performance data. The method is called Primary and Secondary Terms Analysis and Renormalization (PSTAR). In the PSTAR method, renormalized parameters are introduced for the primary terms such that the renormalized energy balance equation is best satisfied in the least squares sense, hence, the name PSTAR. PSTAR allows extraction of building characteristics from short-term tests on a small number of data channels. These can be used for long-term performance prediction (''ratings''), diagnostics, and control of heating, ventilating, and air conditioning systems (HVAC), comparison of design versus actual performance, etc. By combining realistic building models, simple test procedures, and analysis involving linear equations, PSTAR provides a powerful tool for analyzing building energy as well as testing and monitoring. It forms the basis for the Short-Term Energy Monitoring (STEM) project at SERI.

Subbarao, K.

1988-09-01

297

Evidence for Solar Cycle Influence on the Infrared Energy Budget and Radiative Cooling of the Thermosphere  

NASA Technical Reports Server (NTRS)

We present direct observational evidence for solar cycle influence on the infrared energy budget and radiative cooling of the thermosphere. By analyzing nearly five years of data from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument, we show that the annual mean infrared power radiated by the nitric oxide (NO) molecule at 5.3 m has decreased by a factor of 2.9. This decrease is correlated (r = 0.96) with the decrease in the annual mean F10.7 solar index. Despite the sharp decrease in radiated power (which is equivalent to a decrease in the vertical integrated radiative cooling rate), the variability of the power as given in the standard deviation of the annual means remains approximately constant. A simple relationship is shown to exist between the infrared power radiated by NO and the F10.7 index, thus providing a fundamental relationship between solar activity and the thermospheric cooling rate for use in thermospheric models. The change in NO radiated power is also consistent with changes in absorbed ultraviolet radiation over the same time period.

Mlynczak, Martin G.; Martin-Torres, F. Javier; Marshall, B. Thomas; Thompson, R. Earl; Williams, Joshua; Turpin, TImothy; Kratz, D. P.; Russell, James M.; Woods, Tom; Gordley, Larry L.

2007-01-01

298

An integrated life cycle assessment model: Energy and greenhouse gas performance of residential heritage buildings, and the influence of retrofit strategies in the state of Victoria in Australia  

Microsoft Academic Search

Heritage buildings are of significant cultural importance to Australia. They are at risk of becoming obsolete under the stringent building energy efficiency regulations being introduced currently. This article develops an integrated framework combining building energy efficiency simulation and appliance characteristic components, with a five stage life cycle assessment framework. The life cycle performance of eight residential heritage buildings in Victoria

Deepak Sivaraman

299

Development and use of the GREET model to estimate fuel-cycle energy use and emissions of various transportation technologies and fuels  

Microsoft Academic Search

This report documents the development and use of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel- cycle emissions and energy use associated with various transportation fuels for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides,

1996-01-01

300

The concept of dual-boundary forcing in land surface-subsurface interactions of the terrestrial hydrologic and energy cycles  

NASA Astrophysics Data System (ADS)

hydrological processes interact in a complex, nonlinear fashion. It is important to quantify these interactions to understand the overall mechanisms of the coupled water and energy cycles. In this study, the concept of a dual-boundary forcing is proposed that connects the variability of atmospheric (upper boundary) and subsurface (lower boundary) processes to the land surface mass and energy balance components. According to this concept, the space-time patterns of land surface mass and energy fluxes can be explained by the variability of the dominating boundary condition for the exchange processes, which is determined by moisture and energy availability. A coupled subsurface-land surface model is applied on the Rur catchment, Germany, to substantiate the proposed concept. Spectral and geostatistical analysis on the observations and model results show the coherence of different processes at various space-time scales in the hydrological cycle. The spectral analysis shows that atmospheric radiative forcing generally drives the variability of the land surface energy fluxes at the daily time scale, while influence of subsurface hydrodynamics is significant at monthly to multimonth time scales under moisture-limited conditions. The geostatistical analysis demonstrates that atmospheric forcing and groundwater control the spatial variability of land surface processes under energy and moisture-limited conditions, respectively. These results suggest that under moisture-limited conditions, groundwater influences the variability of the land surface mass and energy fluxes. Under energy-limited conditions, on the contrary, variability of land surface processes can be explained by atmospheric forcing alone.

Rahman, M.; Sulis, M.; Kollet, S. J.

2014-11-01

301

A novel determination of density, temperature and symmetry energy for nuclear multi-fragmentation through primary fragment yield reconstruction  

E-print Network

For the first time primary hot isotope distributions are experimentally reconstructed in intermediate heavy ion collisions and used with antisymmetrized molecular dynamics (AMD) calculations to determine density, temperature and symmetry energy coefficient in a self-consistent manner. A kinematical focusing method is employed to reconstruct the primary hot fragment yield distributions for multifragmentation events observed in the reaction system $^{64}$Zn + $^{112}$Sn at 40 MeV/nucleon. The reconstructed yield distributions are in good agreement with the primary isotope distributions of AMD simulations. The experimentally extracted values of the symmetry energy coefficient relative to the temperature, $a_{sym}/T$, are compared with those of the AMD simulations with different density dependence of the symmetry energy term. The calculated $a_{sym}/T$ values changes according to the different interactions. By comparison of the experimental values of $a_{sym}/T$ with those of calculations, the density of the source at fragment formation was determined to be $\\rho /\\rho_{0} = (0.63 \\pm 0.03 )$. Using this density, the symmetry energy coefficient and the temperature are determined in a self-consistent manner as $a_{sym} = (24.7 \\pm 1.9) MeV$ and $T=(4.9 \\pm 0.2)$ MeV

W. Lin; X. Liu; M. R. D. Rodrigues; S. Kowalski; R. Wada; M. Huang; S. Zhang; Z. Chen; J. Wang; G. Q. Xiao; R. Han; Z. Jin; J. Liu; F. Shi; T. Keutgen; K. Hagel; M. Barbui; C. Bottosso; A. Bonasera; J. B. Natowitz; E. J. Kim; T. Materna; L. Qin; P. K. Sahu; K. J. Schmidt; S. Wuenschel; H. Zheng

2014-01-02

302

Combined solar organic Rankine cycle with reverse osmosis desalination process: Energy, exergy, and cost evaluations  

Microsoft Academic Search

Organic Rankine cycles (ORC) have unique properties that are well suited to solar power generation. In this work design and performance calculations are performed using MatLab\\/SimuLink computational environment. The cycle consists of thermal solar collectors (Flat Plate Solar Collector (FPC), or Parabolic Trough Collector (PTC), or Compound Parabolic Concentrator (CPC)) for heat input, expansion turbine for work output, condenser unit

A. S. Nafey; M. A. Sharaf

2010-01-01

303

Homology-mediated end-capping as a primary step of sister chromatid fusion in the breakage-fusion-bridge cycles  

PubMed Central

Breakage-fusion-bridge (BFB) cycle is a series of chromosome breaks and duplications that could lead to the increased copy number of a genomic segment (gene amplification). A critical step of BFB cycles leading to gene amplification is a palindromic fusion of sister chromatids following the rupture of a dicentric chromosome during mitosis. It is currently unknown how sister chromatid fusion is produced from a mitotic break. To delineate the process, we took an integrated genomic, cytogenetic and molecular approach for the recurrent MCL1 amplicon at chromosome 1 in human tumor cells. A newly developed next-generation sequencing-based approach identified a cluster of palindromic fusions within the amplicon at ?50-kb intervals, indicating a series of breaks and fusions by BFB cycles. The physical location of the amplicon (at the end of a broken chromosome) further indicated BFB cycles as underlying processes. Three palindromic fusions were mediated by the homologies between two nearby inverted Alu repeats, whereas the other two fusions exhibited microhomology-mediated events. Such breakpoint sequences indicate that homology-mediated fold-back capping of broken ends followed by DNA replication is an underlying mechanism of sister chromatid fusion. Our results elucidate nucleotide-level events during BFB cycles and end processing for naturally occurring mitotic breaks. PMID:23975201

Marotta, Michael; Chen, Xiongfong; Watanabe, Takaaki; Faber, Pieter W.; Diede, Scott J.; Tapscott, Stephen; Tubbs, Raymond; Kondratova, Anna; Stephens, Robert; Tanaka, Hisashi

2013-01-01

304

Life-cycle fossil energy consumption and greenhouse gas emissions of bioderived chemicals and their conventional counterparts.  

PubMed

Biomass-derived chemical products may offer reduced environmental impacts compared to their fossil-derived counterparts and could improve profit margins at biorefineries when coproduced with higher-volume, lower-profit margin biofuels. It is important to assess on a life-cycle basis the energy and environmental impacts of these bioproducts as compared to conventional, fossil-derived products. We undertook a life-cycle analysis of eight bioproducts produced from either algal-derived glycerol or corn stover-derived sugars. Selected on the basis of technology readiness and market potential, the bioproducts are propylene glycol, 1,3-propanediol, 3-hydroxypropionic acid, acrylic acid, polyethylene, succinic acid, isobutanol, and 1,4-butanediol. We developed process simulations to obtain energy and material flows in the production of each bioproduct and examined sensitivity of these flows to process design assumptions. Conversion process data for fossil-derived products were based on the literature. Conversion process data were combined with upstream parameters in the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model to generate life-cycle greenhouse gas (GHG) emissions and fossil energy consumption (FEC) for each bioproduct and its corresponding petroleum-derived product. The bioproducts uniformly offer GHG emissions reductions compared to their fossil counterparts ranging from 39 to 86% on a cradle-to-grave basis. Similarly, FEC was lower for bioproducts than for conventional products. PMID:25380298

Adom, Felix; Dunn, Jennifer B; Han, Jeongwoo; Sather, Norm

2014-12-16

305

Charge composition of high energy heavy primary cosmic ray nuclei. Ph.D. Thesis - Catholic Univ. of Am.  

NASA Technical Reports Server (NTRS)

A detailed study of the charge composition of primary cosmic radiation for about 5000 charged nuclei from neon to iron with energies greater than 1.16 GeV/nucleon is presented. Values are obtained after corrections were made for detector dependences, atmospheric attenuation, and solar modulation. New values of 38.5, 32.4, 23.7, and 16.8 g/sq cm for the attenuation mean free paths in air for the same charge groups are presented.

Price, R. D.

1974-01-01

306

miR-221/222 compensates for Skp2-mediated p27 degradation and is a primary target of cell cycle regulation by prostacyclin and cAMP.  

PubMed

p27(kip1) (p27) is a cdk-inhibitory protein with an important role in the proliferation of many cell types. SCF(Skp2) is the best studied regulator of p27 levels, but Skp2-mediated p27 degradation is not essential in vivo or in vitro. The molecular pathway that compensates for loss of Skp2-mediated p27 degradation has remained elusive. Here, we combine vascular injury in the mouse with genome-wide profiling to search for regulators of p27 during cell cycling in vivo. This approach, confirmed by RT-qPCR and mechanistic analysis in primary cells, identified miR-221/222 as a compensatory regulator of p27. The expression of miR221/222 is sensitive to proteasome inhibition with MG132 suggesting a link between p27 regulation by miRs and the proteasome. We then examined the roles of miR-221/222 and Skp2 in cell cycle inhibition by prostacyclin (PGI(2)), a potent cell cycle inhibitor acting through p27. PGI(2) inhibited both Skp2 and miR221/222 expression, but epistasis, ectopic expression, and time course experiments showed that miR-221/222, rather than Skp2, was the primary target of PGI(2). PGI(2) activates Gs to increase cAMP, and increasing intracellular cAMP phenocopies the effect of PGI(2) on p27, miR-221/222, and mitogenesis. We conclude that miR-221/222 compensates for loss of Skp2-mediated p27 degradation during cell cycling, contributes to proteasome-dependent G1 phase regulation of p27, and accounts for the anti-mitogenic effect of cAMP during growth inhibition. PMID:23409140

Castagnino, Paola; Kothapalli, Devashish; Hawthorne, Elizabeth A; Liu, Shu-Lin; Xu, Tina; Rao, Shilpa; Yung, Yuval; Assoian, Richard K

2013-01-01

307

Life cycle energy and greenhouse gas emissions for an ethanol production process based on blue-green algae.  

PubMed

Ethanol can be produced via an intracellular photosynthetic process in cyanobacteria (blue-green algae), excreted through the cell walls, collected from closed photobioreactors as a dilute ethanol-in-water solution, and purified to fuel grade ethanol. This sequence forms the basis for a biofuel production process that is currently being examined for its commercial potential. In this paper, we calculate the life cycle energy and greenhouse gas emissions for three different system scenarios for this proposed ethanol production process, using process simulations and thermodynamic calculations. The energy required for ethanol separation increases rapidly for low initial concentrations of ethanol, and, unlike other biofuel systems, there is little waste biomass available to provide process heat and electricity to offset those energy requirements. The ethanol purification process is a major consumer of energy and a significant contributor to the carbon footprint. With a lead scenario based on a natural-gas-fueled combined heat and power system to provide process electricity and extra heat and conservative assumptions around the ethanol separation process, the net life cycle energy consumption, excluding photosynthesis, ranges from 0.55 MJ/MJ(EtOH) down to 0.20 MJ/ MJ(EtOH), and the net life cycle greenhouse gas emissions range from 29.8 g CO?e/MJ(EtOH) down to 12.3 g CO?e/MJ(EtOH) for initial ethanol concentrations from 0.5 wt % to 5 wt %. In comparison to gasoline, these predicted values represent 67% and 87% reductions in the carbon footprint for this ethanol fuel on a energy equivalent basis. Energy consumption and greenhouse gas emissions can be further reduced via employment of higher efficiency heat exchangers in ethanol purification and/ or with use of solar thermal for some of the process heat. PMID:20968295

Luo, Dexin; Hu, Zushou; Choi, Dong Gu; Thomas, Valerie M; Realff, Matthew J; Chance, Ronald R

2010-11-15

308

78 FR 43870 - Hydrogen Energy California's Integrated Gasification Combined Cycle Project; Preliminary Staff...  

Federal Register 2010, 2011, 2012, 2013

...project would demonstrate integrated gasification combined cycle (IGCC) and carbon capture technology on a commercial-scale in a...generator, a steam turbine, and associated facilities. The IGCC technology would turn a fuel blend consisting of 75 percent...

2013-07-22

309

Environmental Life-cycle Assessment of Passenger Transportation: A Detailed Methodology for Energy,  

E-print Network

, Greenhouse Gas, and Criteria Pollutant Inventories of Automobiles, Buses, Light Rail, Heavy Rail and Air Pollutant Inventories of Automobiles, Buses, Light Rail, Heavy Rail and Air Working Paper University......................................................................................................................................16 5 Life-cycle Inventory of Automobiles and Urban Buses

California at Berkeley, University of

310

77 FR 18272 - Uranium Enrichment Fuel Cycle Facility Inspection Reports Regarding Louisiana Energy Services LLC...  

Federal Register 2010, 2011, 2012, 2013

...Docket No. 70-3103; NRC-2010-0264] Uranium Enrichment Fuel Cycle Facility Inspection...1954, as amended. The introduction of uranium hexafluoride into any module of the...Commission. Brian W. Smith, Chief, Uranium Enrichment Branch, Division of Fuel...

2012-03-27

311

78 FR 23312 - Uranium Enrichment Fuel Cycle Inspection Reports Regarding Louisiana Energy Services, National...  

Federal Register 2010, 2011, 2012, 2013

...Docket No. 70-3103; NRC-2010-0264] Uranium Enrichment Fuel Cycle Inspection Reports...and has authorized the introduction of uranium hexafluoride (UF 6 ) into cascades...Commission. Brian W. Smith, Chief, Uranium Enrichment Branch, Division of Fuel...

2013-04-18

312

78 FR 63518 - Uranium Enrichment Fuel Cycle Inspection Reports Regarding Louisiana Energy Services, National...  

Federal Register 2010, 2011, 2012, 2013

...Docket No. 70-3103; NRC-2010-0264] Uranium Enrichment Fuel Cycle Inspection Reports...and has authorized the introduction of uranium hexafluoride (UF 6 ) into cascades...Commission. Brian W. Smith, Chief, Uranium Enrichment Branch, Division of Fuel...

2013-10-24

313

Energy Conversion Alternatives Study (ECAS), Westinghouse Phase 1. Vol. VIIII: closed-cycle MHD. Final report  

Microsoft Academic Search

A closed-cycle MHD system for an electric power plant was studied. It consists of 3 interlocking loops, an external heating loop, a closed-cycle cesium seeded argon nonequilibrium ionization MHD loop, and a steam bottomer. A MHD duct maximum temperature of 2366 K (3800 F), a pressure of 0.939 MPa (9.27 atm) and a Mach number of 0.9 are found to

Tsu

1976-01-01

314

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 9: Closed-cycle MHD  

Microsoft Academic Search

A closed-cycle MHD system for an electric power plant was studied. It consists of 3 interlocking loops, an external heating loop, a closed-cycle cesium seeded argon nonequilibrium ionization MHD loop, and a steam bottomer. A MHD duct maximum temperature of 2366 K (3800 F), a pressure of 0.939 MPa (9.27 atm) and a Mach number of 0.9 are found to

T. C. Tsu

1976-01-01

315

Life Cycle Assessment of the Energy Independence and Security Act of 2007: Ethanol - Global Warming Potential and Environmental Emissions  

Microsoft Academic Search

The objective of this study is to use life cycle assessment (LCA) to evaluate the global warming potential (GWP), water use, and net energy value (NEV) associated with the EISA-mandated 16 bgy cellulosic biofuels target, which is assumed in this study to be met by cellulosic-based ethanol, and the EISA-mandated 15 bgy conventional corn ethanol target. Specifically, this study compares,

G. A. Heath; D. D. Hsu; D. Inman; A. Aden; M. K. Mann

2009-01-01

316

Energy, angular and spatial distributions of primary electrons inside photoconducting materials for digital mammography: Monte Carlo simulation studies.  

PubMed

Materials such as a-Se, a-As(2)Se(3), GaSe, GaAs, Ge, CdTe, CdZnTe, Cd(0.8)Zn(0.2)Te, ZnTe, PbO, TlBr, PbI(2) and HgI(2) are potential candidates as photoconductors in direct detectors for digital mammography. The x-ray induced primary electrons inside a photoconductor's bulk comprise the initial signal that propagates and forms the final signal (image) on the detector's electrodes. An already developed model for a-Se has been properly extended to simulate the primary electron production in the materials mentioned. Primary electron characteristics, such as their energy, angular and spatial distributions that strongly influence the characteristics of the final image, were studied for both monoenergetic and polyenergetic x-ray spectra in the mammographic energy range. The characteristic feature in the electron energy distributions for PbI(2) and HgI(2) is the atomic deexcitation peaks, whereas for the rest of the materials their shape can also be influenced by the electrons produced from primary photons. The electrons have a small tendency to be forward ejected whereas they prefer to be ejected perpendicular (theta = pi/2) to the incident beam's axis and at two lobes around phi = 0 and phi = pi. At practical mammographic energies (15-40 keV) a-Se, a-As(2)Se(3) and Ge have the minimum azimuthal uniformity whereas CdZnTe, Cd(0.8)Zn(0.2)Te and CdTe the maximum one. The spatial distributions for a-Se, a-As(2)Se(3), GaSe, GaAs, Ge, PbO and TlBr are almost independent of the polyenergetic spectrum, while those for CdTe, CdZnTe, Cd(0.8)Zn(0.2)Te, ZnTe, PbI(2) and HgI(2) have a spectrum dependence. In the practical mammographic energy range and at this primitive stage of primary electron production, a-Se has the best inherent spatial resolution as compared to the rest of the photoconductors. PbO has the minimum bulk space in which electrons can be produced whereas CdTe has the maximum one. PMID:17951854

Sakellaris, T; Spyrou, G; Tzanakos, G; Panayiotakis, G

2007-11-01

317

Results of the Collaborative Energy and Water Cycle Information Services (CEWIS) Workshop on Heterogeneous Dataset Analysis Preparation  

NASA Astrophysics Data System (ADS)

In support of the NASA Energy and Water Cycle Study (NEWS), the Collaborative Energy and Water Cycle Information Services (CEWIS), sponsored by NEWS Program Manager Jared Entin, was initiated to develop an evolving set of community-based data and information services that would facilitate users to locate, access, and bring together multiple distributed heterogeneous energy and water cycle datasets. The CEWIS workshop was the initial step of the process, starting with identifying and scoping the issues, as defined by the community. Thus, the purpose of the workshop was to: - Determine the data preparations, challenges, and roadblocks encountered by NEWS PI Teams to perform heterogeneous multi-data science/validation - Receive feedback regarding potential solutions to roadblocks that are in the way of bringing distributed heterogeneous datasets together By understanding the issues of multi-dataset Earth science research, the scope, feasibility, and roadmap for resolving expressed issues can be mapped out. This presentation reports on the findings of the workshop, which include: - Participant responses to survey questions pertaining interoperability of heterogeneous datasets. - Participant presentations that provide real multi-dataset research preparation experiences. - Participants developed multi-dataset preparation scenarios - Discussion at the end of the meeting providing insights on where to go from here. It is hoped that this presentation will encourage further discussions and collaborations on behalf of promising information technologies that would facilitate the preparation of heterogeneous datasets for science and applications research.

Kempler, S. J.; Teng, W. L.; Acker, J. G.; Belvedere, D. R.; Liu, Z.; Leptoukh, G. G.

2010-12-01

318

Recapitulation of the Sexual Cycle of the Primary Fungal Pathogen Cryptococcus neoformans var. gattii: Implications for an Outbreak on Vancouver Island, Canada  

Microsoft Academic Search

Cryptococcus neoformans is a human fungal pathogen that exists as three distinct varieties or sibling species: the predominantly opportunistic pathogens C. neoformans var. neoformans (serotype D) and C. neoformans var. grubii (serotype A) and the primary pathogen C. neoformans var. gattii (serotypes B and C). While serotypes A and D are cosmopolitan, serotypes B and C are typically restricted to

James A. Fraser; Ryan L. Subaran; Connie B. Nichols; Joseph Heitman

2003-01-01

319

Nuclear energy in Europe: uranium flow modeling and fuel cycle scenario trade-offs from a sustainability perspective.  

PubMed

The European nuclear fuel cycle (covering the EU-27, Switzerland and Ukraine) was modeled using material flow analysis (MFA).The analysis was based on publicly available data from nuclear energy agencies and industries, national trade offices, and nongovernmental organizations. Military uranium was not considered due to lack of accessible data. Nuclear fuel cycle scenarios varying spent fuel reprocessing, depleted uranium re-enrichment, enrichment assays, and use of fast neutron reactors, were established. They were then assessed according to environmental, economic and social criteria such as resource depletion, waste production, chemical and radiation emissions, costs, and proliferation risks. The most preferable scenario in the short term is a combination of reduced tails assay and enrichment grade, allowing a 17.9% reduction of uranium demand without significantly increasing environmental, economic, or social risks. In the long term, fast reactors could theoretically achieve a 99.4% decrease in uranium demand and nuclear waste production. However, this involves important costs and proliferation risks. Increasing material efficiency is not systematically correlated with the reduction of other risks. This suggests that an overall optimization of the nuclear fuel cycle is difficult to obtain. Therefore, criteria must be weighted according to stakeholder interests in order to determine the most sustainable solution. This paper models the flows of uranium and associated materials in Europe, and provides a decision support tool for identifying the trade-offs of the alternative nuclear fuel cycles considered. PMID:21275398

Tendall, Danielle M; Binder, Claudia R

2011-03-15

320

Energy efficiency and environmental performance of bioethanol production from sweet sorghum stem based on life cycle analysis.  

PubMed

Life cycle analysis method was used to evaluate the energy efficiency and environmental performance of bioethanol production from sweet sorghum stem in China. The scope covers three units, including plant cultivation, feedstock transport, and bioethanol conversion. Results show that the net energy ratio was 1.56 and the net energy gain was 8.37 MJ/L. Human toxicity was identified as the most significant negative environmental impact, followed by eutrophication and acidification. Steam generation in the bioethanol conversion unit contributed 82.28% and 48.26% to total human toxicity and acidification potential, respectively. Fertilizers loss from farmland represented 67.23% of total eutrophication potential. The results were significantly affected by the inventory allocation methods, vinasse reusing approaches, and feedstock yields. Reusing vinasse as fuel for steam generation and better cultivation practice to control fertilizer loss could significantly contribute to enhance the energy efficiency and environmental performance of bioethanol production from sweet sorghum stem. PMID:24787319

Wang, Mingxin; Chen, Yahui; Xia, Xunfeng; Li, Jun; Liu, Jianguo

2014-07-01

321

Rock Cycle  

NSDL National Science Digital Library

The Rock Cycle SciPack explores different kinds and categories of rocks, the major processes through which they form and the cyclical nature of the formation and transformation of rock materials. The focus is on topics supporting Standards and Benchmarks related to the rock cycle as part of the transfer and transformation of matter and energy in Earth's system as well as a sense of the time scales involved and how rocks provide information about their own development and the history of Earth.In addition to comprehensive inquiry-based learning materials tied to Science Education Standards and Benchmarks, the SciPack includes the following additional components:? Pedagogical Implications section addressing common misconceptions, teaching resources and strand maps linking grade band appropriate content to standards. ? Access to one-on-one support via e-mail to content "Wizards".? Final Assessment which can be used to certify mastery of the concepts.Learning Outcomes:Rock Cycle: Categories by Process? List the three different types of rock. ? Make appropriate observations about rocks (e.g. describe rock composition and texture).? Make appropriate observations about the general environments in which the rocks formed.Rock Cycle: Environments of Formation? Realize that different rocks have specific origins, and that they are the product of any number of processes.? Identify the processes through which igneous, sedimentary, and metamorphic rock form.? Explain the role of intermediary materials such as sediment and magma in the formation of different kinds of rock.? Provide an overarching description of the steps in the rock cycle, the formation of sedimentary rock, the re-forming of rock by heat and pressure, and the process by which re-formed rock can return to the surface.Rock Cycle: Cycling? Recognize the formation and transformation processes as part of a continuing cycle.? Identify that while the form and location of different rocks change over time, the amount of material and the distribution among the elements remains constant.? Explain the different processes or paths that each type of rock may take in the rock cycle.Rock Cycle: Earth's Autobiography? State the amount of time over which the rock cycle has been in operation (4 billion years rather than 40 million or 400 million).? Recognize that the processes at work in the present are the same as those at work in the distant past.? Describe how rock formations and characteristics can be used to determine how different rock formed, making appropriate interpretations about the source of the rock, history and processes, and the environment of formation.? Describe how rocks provide a history of the changing surface of Earth and its lifeforms.

National Science Teachers Association (NSTA)

2007-03-21

322

Formulating energy policies related to fossil fuel use: Critical uncertainties in the global carbon cycle  

SciTech Connect

The global carbon cycle is the dynamic interaction among the earth's carbon sources and sinks. Four reservoirs can be identified, including the atmosphere, terrestrial biosphere, oceans, and sediments. Atmospheric CO{sub 2} concentration is determined by characteristics of carbon fluxes among major reservoirs of the global carbon cycle. The objective of this paper is to document the knowns, and unknowns and uncertainties associated with key questions that if answered will increase the understanding of the portion of past, present, and future atmospheric CO{sub 2} attributable to fossil fuel burning. Documented atmospheric increases in CO{sub 2} levels are thought to result primarily from fossil fuel use and, perhaps, deforestation. However, the observed atmospheric CO{sub 2} increase is less than expected from current understanding of the global carbon cycle because of poorly understood interactions among the major carbon reservoirs. 87 refs.

Post, W.M.; Dale, V.H.; DeAngelis, D.L.; Mann, L.K.; Mulholland, P.J.; O'Neill, R.V.; Peng, T.-H.; Farrell, M.P.

1990-01-01

323

Reviewing the carbon footprint analysis of hotels: Life Cycle Energy Analysis (LCEA) as a holistic method for carbon impact appraisal of tourist accommodation  

Microsoft Academic Search

This study discusses the potential for Life Cycle Assessment (LCA) to be utilized for the environmental assessment of tourism accommodation facilities, and their contribution to global carbon footprint. To demonstrate the viability of employing LCA in the hotel sector, its simplified derivative, Life Cycle Energy Analysis (LCEA), is applied to two tourism accommodation facilities in Poole, Dorset (UK) to quantify

Viachaslau Filimonau; Janet Dickinson; Derek Robbins; Mark A. J. Huijbregts

2011-01-01

324

Research in Support of the Use of Rankine Cycle Energy Conversion Systems for Space Power and Propulsion  

NASA Technical Reports Server (NTRS)

This is the report of a Scientific Working Group (SWG) formed by NASA to determine the feasibility of using a liquid metal cooled nuclear reactor and Rankine energy conversion cycle for dual purpose power and propulsion in space. This is a high level technical report which is intended for use by NASA management in program planning. The SWG was composed of a team of specialists in nuclear energy and multiphase flow and heat transfer technology from academia, national laboratories, NASA and industry. The SWG has identified the key technology issues that need to be addressed and have recommended an integrated short term (approx. 2 years) and a long term (approx. 10 year) research and development (R&D) program to qualify a Rankine cycle power plant for use in space. This research is ultimately intended to give NASA and its contractors the ability to reliably predict both steady and transient multiphase flow and heat transfer phenomena at reduced gravity, so they can analyze and optimize designs and scale-up experimental data on Rankine cycle components and systems. In addition, some of these results should also be useful for the analysis and design of various multiphase life support and thermal management systems being considered by NASA.

Lahey, Richard T., Jr.; Dhir, Vijay

2004-01-01

325

The Oxygen Cycle.  

ERIC Educational Resources Information Center

Produced for primary grades, this booklet provides study of the oxygen-carbon dioxide cycle in nature. Line drawings, a minimum amount of narrative, and a glossary of terms make up its content. The booklet is designed to be used as reading material, a coloring book, or for dramatic arts with students acting out parts of the cycle. This work was…

Swant, Gary D.

326

Power Plant Cycling Costs  

SciTech Connect

This report provides a detailed review of the most up to date data available on power plant cycling costs. The primary objective of this report is to increase awareness of power plant cycling cost, the use of these costs in renewable integration studies and to stimulate debate between policymakers, system dispatchers, plant personnel and power utilities.

Kumar, N.; Besuner, P.; Lefton, S.; Agan, D.; Hilleman, D.

2012-07-01

327

Thermochemical cycles  

NASA Technical Reports Server (NTRS)

The thermochemical production of hydrogen is described along with the HYDRGN computer program which attempts to rate the various thermochemical cycles. Specific thermochemical cycles discussed include: iron sulfur cycle; iron chloride cycle; and hybrid sulfuric acid cycle.

Funk, J. E.; Soliman, M. A.; Carty, R. H.; Conger, W. L.; Cox, K. E.; Lawson, D.

1975-01-01

328

Navigating wastewater energy recovery strategies: a life cycle comparison of anaerobic membrane bioreactor and conventional treatment systems with anaerobic digestion.  

PubMed

The objective of this study was to evaluate emerging anaerobic membrane bioreactor (AnMBR) technology in comparison with conventional wastewater energy recovery technologies. Wastewater treatment process modeling and systems analyses were combined to evaluate the conditions under which AnMBR may produce more net energy and have lower life cycle environmental emissions than high rate activated sludge with anaerobic digestion (HRAS+AD), conventional activated sludge with anaerobic digestion (CAS+AD), and an aerobic membrane bioreactor with anaerobic digestion (AeMBR+AD). For medium strength domestic wastewater treatment under baseline assumptions at 15 °C, AnMBR recovered 49% more energy as biogas than HRAS+AD, the most energy positive conventional technology considered, but had significantly higher energy demands and environmental emissions. Global warming impacts associated with AnMBR were largely due to emissions of effluent dissolved methane. For high strength domestic wastewater treatment, AnMBR recovered 15% more net energy than HRAS+AD, and the environmental emissions gap between the two systems was reduced. Future developments of AnMBR technology in low energy fouling control, increased flux, and management of effluent methane emissions would make AnMBR competitive with HRAS+AD. Rapid advancements in AnMBR technology must continue to achieve its full economic and environmental potential as an energy recovery strategy for domestic wastewater. PMID:24742289

Smith, Adam L; Stadler, Lauren B; Cao, Ling; Love, Nancy G; Raskin, Lutgarde; Skerlos, Steven J

2014-05-20

329

Life cycle assessment of energy from solid waste—part 1: general methodology and results  

Microsoft Academic Search

The overall goal of the present study is to evaluate different strategies for treatment of solid waste in Sweden based on a life cycle perspective. Important goals are to identify advantages and disadvantages of different methods for treatment of solid waste, and to identify critical factors in the systems, including the background systems, which may significantly influence the results. Included

Göran Finnveden; Jessica Johansson; Per Lind; Åsa Moberg

2005-01-01

330

Organic Rankine cycles (ORCs) for energy recovery from molten carbonate fuel cells  

Microsoft Academic Search

Waste heat from molten carbonate fuel cell plant (MCFC) is available in quantities and at temperatures suitable for generation of additional power by means of a recovery Rankine cycle. The moderate capacity of the first commercial plants suggest the use of an organic working medium rather than steam. A number of fluids are examined; they all share adequate technical and

Gianfranco Angelino; Piero Colonna di Paliano

2000-01-01

331

Cycling performance of the iron-chromium redox energy storage system  

NASA Astrophysics Data System (ADS)

Extended charge-discharge cycling of this electrochemical storage system at 65 C was performed on 14.5 sq cm single cells and a four cell, 867 sq cm bipolar stack. Both the anolyte and catholyte reactant fluids contained 1 molar concentrations of iron and chromium chlorides in hydrochloric acid and were separated by a low-selectivity, cation-exchange membrane. The effect of cycling on the chromium electrode and the cation-exchange membrane was determined. Bismuth and bismuth-lead catalyzed chromium electrodes and a radiation-grafted polyethylene membrane were evaluated by cycling between 5 and 85 percent state-of-charge at 80 mA/sq cm and by periodic charge-discharge polarization measurements to 140 mA/sq cm. Gradual performance losses were observed during cycling but were recoverable by completely discharging the system. Good scale-up to the 867 sq cm stack was achieved. The only difference appeared to be an unexplained resistive-type loss which resulted in a 75 percent W-hr efficiency (at 80 mA/sq cm versus 81 percent for the 14.5 sq cm cell). A new rebalance cell was developed to maintain reactant ionic balance. The cell successfully reduced ferric ions in the iron reactant stream to ferrous ions while chloride ions were oxidized to chlorine gas.

Gahn, R. F.; Hagedorn, N. H.; Johnson, J. A.

1985-12-01

332

Cycling Performance of the Iron-Chromium Redox Energy Storage System  

NASA Technical Reports Server (NTRS)

Extended charge-discharge cycling of this electrochemical storage system at 65 C was performed on 14.5 sq cm single cells and a four cell, 867 sq cm bipolar stack. Both the anolyte and catholyte reactant fluids contained 1 molar concentrations of iron and chromium chlorides in hydrochloric acid and were separated by a low-selectivity, cation-exchange membrane. The effect of cycling on the chromium electrode and the cation-exchange membrane was determined. Bismuth and bismuth-lead catalyzed chromium electrodes and a radiation-grafted polyethylene membrane were evaluated by cycling between 5 and 85 percent state-of-charge at 80 mA/sq cm and by periodic charge-discharge polarization measurements to 140 mA/sq cm. Gradual performance losses were observed during cycling but were recoverable by completely discharging the system. Good scale-up to the 867 sq cm stack was achieved. The only difference appeared to be an unexplained resistive-type loss which resulted in a 75 percent W-hr efficiency (at 80 mA/sq cm versus 81 percent for the 14.5 sq cm cell). A new rebalance cell was developed to maintain reactant ionic balance. The cell successfully reduced ferric ions in the iron reactant stream to ferrous ions while chloride ions were oxidized to chlorine gas.

Gahn, R. F.; Hagedorn, N. H.; Johnson, J. A.

1985-01-01

333

Cycling performance of the iron-chromium redox energy storage system  

NASA Technical Reports Server (NTRS)

Extended charge-discharge cycling of this electrochemical storage system at 65 C was performed on 14.5 sq cm single cells and a four cell, 867 sq cm bipolar stack. Both the anolyte and catholyte reactant fluids contained 1 molar concentrations of iron and chromium chlorides in hydrochloric acid and were separated by a low-selectivity, cation-exchange membrane. The effect of cycling on the chromium electrode and the cation-exchange membrane was determined. Bismuth and bismuth-lead catalyzed chromium electrodes and a radiation-grafted polyethylene membrane were evaluated by cycling between 5 and 85 percent state-of-charge at 80 mA/sq cm and by periodic charge-discharge polarization measurements to 140 mA/sq cm. Gradual performance losses were observed during cycling but were recoverable by completely discharging the system. Good scale-up to the 867 sq cm stack was achieved. The only difference appeared to be an unexplained resistive-type loss which resulted in a 75 percent W-hr efficiency (at 80 mA/sq cm versus 81 percent for the 14.5 sq cm cell). A new rebalance cell was developed to maintain reactant ionic balance. The cell successfully reduced ferric ions in the iron reactant stream to ferrous ions while chloride ions were oxidized to chlorine gas.

Gahn, R. F.; Hagedorn, N. H.; Johnson, J. A.

1985-01-01

334

Energy 3: Fossil Fuel Use and its Consequences - The Carbon Cycle  

NSDL National Science Digital Library

This video goes through the carbon cycle and describes how using fossil fuels threatens the foundation of the aquatic global food chain. This video is part of the Sustainability Learning Suites, made possible in part by a grant from the National Science Foundation. See 'Learn more about this resource' for Learning Objectives and Activities.

Linda Vanasupa

335

Thermodynamics -2 A cogeneration plant (plant which provides both electricity and thermal energy) executes a cycle  

E-print Network

plant using the same heat source and heat sinks. e. [25 pts] Determine the minimum rate of heat input to the plant to generate 300 MW of power while providing 150 MW of heat to the 400 K heat sink. Steam Generator) executes a cycle while receiving from a thermal reservoir at 900 K, supplying heat to a process at 400 K

Virginia Tech

336

Wind Energy Electrical Power Generation: Industrial Life Cycle of a Radical Innovation  

Microsoft Academic Search

This study addresses past, current and future development of the wind electrical power industry, that began prior to 1890 in Cleveland, Ohio and Askov, Denmark... Overcoming technological, business, societal and political hurdles required approximately 120 years of exploration to establish wind electricity generation as a radical innovation entering the acceleration stage of the industrial technology life cycle. Further growth and

J. P. Dismukes; L. K. Miller; A. Solocha; S. Jagani; J. A. Bers

2007-01-01

337

77 FR 65729 - Uranium Enrichment Fuel Cycle Facility Inspection Reports Regarding Louisiana Energy Services LLC...  

Federal Register 2010, 2011, 2012, 2013

...Docket No. 70-3103; NRC-2010-0264] Uranium Enrichment Fuel Cycle Facility Inspection...1954, as amended. The introduction of uranium hexafluoride into any module of the National...Regulatory Commission Brian W. Smith, Chief, Uranium Enrichment Branch, Division of Fuel...

2012-10-30

338

Energy conversion efficiency of hybrid electric heavy-duty vehicles operating according to diverse drive cycles  

Microsoft Academic Search

Energy consumption and exhaust emissions of hybrid electric vehicles (HEVs) strongly depend on the HEV topology, power ratios of their components and applied control strategy. Combined analytical and simulation approach was applied to analyze energy conversion efficiency of different HEV topologies. Analytical approach is based on the energy balance equations and considers all energy paths in the HEVs from the

Titina Banjac; Ferdinand Trenc; Tomaž Katrašnik

2009-01-01

339

Case study: molasses as the primary energy source on an organic grazing dairy  

Technology Transfer Automated Retrieval System (TEKTRAN)

Organic dairies face many challenges, one of which is the high cost of purchased organic grains. Molasses may be a less expensive energy alternative. However, anecdotal results have been mixed for farms that used molasses as the sole energy source. This research project quantified animal performance...

340

Relative response of alanine dosemeters for high-energy electrons determined using a Fricke primary standard.  

PubMed

A significant proportion of cancer patients is treated using MeV electron radiation. One of the measurement methods which is likely to furnish reliable dose values also under non-reference conditions is the dosimetry using alanine and read-out via electron spin resonance (ESR). The system has already proven to be suitable for QA purposes for modern radiotherapy involving megavoltage x-rays. In order to render the secondary standard measurement system of the Physikalisch-Technische Bundesanstalt based on alanine/ESR useable for dosimetry in radiotherapy, the dose-to-water (D(W)) response of the dosemeter needs to be known for relevant radiation qualities. For MeV electrons, the D(W) response was determined using the Fricke primary standard of the Swiss Federal Office of Metrology. Since there were no citable detailed publications on the Swiss primary standard available, this measurement system is described in some detail. The experimental results for the D(W) response are compared to results of Monte Carlo simulations which model in detail the beams furnished by the electron accelerator as well as the geometry of the detectors. The agreement between experiment and simulation is very good, as well as the agreement with results published by the National Research Council of Canada which are based on a different primary standard. No significant dependence of the D(W) response was found in the range between 6 and 20?MeV. It is therefore suggested to use a unique correction factor k(E) for alanine for all MeV qualities of k(E) = 1.012 ± 0.010. PMID:22349609

Vörös, Sándor; Anton, Mathias; Boillat, Bénédicte

2012-03-01

341

Accepted for publication in Energy Policy Greenhouse-gas Emissions from Solar Electric-and Nuclear Power: A Life-cycle  

E-print Network

Accepted for publication in Energy Policy Greenhouse-gas Emissions from Solar Electric- and Nuclear, photovoltaic, nuclear, life cycle 1 #12;Introduction The production of energy by burning fossil fuels generates, it is envisioned that expanding generation technologies based on nuclear power and renewable energy sources would

342

High energy neutrinos from primary cosmic rays accelerated in the cores of active galaxies  

NASA Technical Reports Server (NTRS)

The spectra and high-energy neutrino fluxes are calculated from photomeson production in active galactic nuclei (AGN) such as quasars and Seyfert galaxies using recent UV and X-ray observations to define the photon fields and an accretion-disk shock-acceleration model for producing ultrahigh-energy cosmic rays in the AGN. Collectively AGN should produce the dominant isotropic neutrino background between 10 exp 4 and 10 exp 10 GeV. Measurement of this background could be critical in determining the energy-generation mechanism, evolution, and distribution of AGN. High-energy background spectra and spectra from bright AGN such as NGC4151 and 3C273 are predicted which should be observable with present detectors. High energy AGN nus should produce a sphere of stellar disruption around their cores which could explain their observed broad-line emission regions.

Stecker, F. W.; Done, C.; Salamon, M. H.; Sommers, P.

1991-01-01

343

The Energy Return on Energy Investment (EROI) of Photovoltaics: Methodology and Comparisons with Fossil Fuel Life Cycles  

E-print Network

with Fossil Fuel Life Cycles Marco Raugei*1,2 , Pere Fullana-i-Palmer1 and Vasilis Fthenakis2,3 1 UNESCO Chair-term viability. The EROI of conventional thermal electricity from fossil fuels has been viewed as being much and present updated EROI values for a range of modern PV systems, in comparison to conventional fossil-fuel

344

Energy independent uptake and release of polystyrene nanoparticles in primary mammalian cell cultures.  

PubMed

Nanoparticle (NPs) delivery systems in vivo promises to overcome many obstacles associated with the administration of drugs, vaccines, plasmid DNA and RNA materials, making the study of their cellular uptake a central issue in nanomedicine. The uptake of NPs may be influenced by the cell culture stage and the NPs physical-chemical properties. So far, controversial data on NPs uptake have been derived owing to the heterogeneity of NPs and the general use of immortalized cancer cell lines that often behave differently from each other and from primary mammalian cell cultures. Main aims of the present study were to investigate the uptake, endocytosis pathways, intracellular fate and release of well standardized model particles, i.e. fluorescent 44nm polystyrene NPs (PS-NPs), on two primary mammalian cell cultures, i.e. bovine oviductal epithelial cells (BOEC) and human colon fibroblasts (HCF) by confocal microscopy and spectrofluorimetric analysis. Different drugs and conditions that inhibit specific internalization routes were used to understand the mechanisms that mediate PS-NP uptake. Our data showed that PS-NPs are rapidly internalized by both cell types 1) with similar saturation kinetics; 2) through ATP-independent processes, and 3) quickly released in the culture medium. Our results suggest that PS-NPs are able to rapidly cross the cell membrane through passive translocation during both uptake and release, and emphasize the need to carefully design NPs for drug delivery, to ensure their selective uptake and to optimize their retainment in the targeted cells. PMID:25246129

Fiorentino, Ilaria; Gualtieri, Roberto; Barbato, Vincenza; Mollo, Valentina; Braun, Sabrina; Angrisani, Alberto; Turano, Mimmo; Furia, Maria; Netti, Paolo A; Guarnieri, Daniela; Fusco, Sabato; Talevi, Riccardo

2015-01-15

345

Thermal and environmental characteristics of the primary equipment of the 480-MW Razdan-5 power-generating plant operating as a combined-cycle plant  

NASA Astrophysics Data System (ADS)

Results of thermal tests of 480-MW power-generating Unit 5 of Razdan Thermal Power Plant (hereinafter, Razdan-5 power unit) are presented. The tests were carried out by LvivORGRES after an integration trial of the power unit. The aim of the tests was thermal characterization of the steam boiler and the steam turbine when the power unit operates as a combined-cycle plant. The economic efficiency of the boiler and the turbine and the environmental characteristics of the power unit are determined and the calculated and the actual values are compared. The specific heat gross and net rates required for the power unit to generate the electric power are established.

Sargsyan, K. B.; Eritsyan, S. Kh.; Petrosyan, G. S.; Avtandilyan, A. V.; Gevorkyan, A. R.; Klub, M. V.

2015-01-01

346

Application of a Tractive Energy Analysis to Quantify the Benefits of Advanced Efficiency Technologies Using Characteristic Drive Cycle Data  

SciTech Connect

Accurately predicting the fuel savings that can be achieved with the implementation of various technologies developed for fuel efficiency can be very challenging, particularly when considering combinations of technologies. Differences in the usage of highway vehicles can strongly influence the benefits realized with any given technology, which makes generalizations about fuel savings inappropriate for different vehicle applications. A model has been developed to estimate the potential for reducing fuel consumption when advanced efficiency technologies, or combinations of these technologies, are employed on highway vehicles, particularly medium- and heavy-duty trucks. The approach is based on a tractive energy analysis applied to drive cycles representative of the vehicle usage, and the analysis specifically accounts for individual energy loss factors that characterize the technologies of interest. This tractive energy evaluation is demonstrated by analyzing measured drive cycles from a long-haul trucking fleet and the results of an assessment of the fuel savings potential for combinations of technologies are presented. The results of this research will enable more reliable estimates of the fuel savings benefits that can be realized with particular technologies and technology combinations for individual trucking applications so that decision makers can make informed investment decisions for the implementation of advanced efficiency technologies.

LaClair, Tim J [ORNL

2012-01-01

347

Environmental assessmental, geothermal energy, Heber geothermal binary-cycle demonstration project: Imperial County, California  

SciTech Connect

The proposed design, construction, and operation of a commercial-scale (45 MWe net) binary-cycle geothermal demonstration power plant are described using the liquid-dominated geothermal resource at Heber, Imperial County, California. The following are included in the environmental assessment: a description of the affected environment, potential environmental consequences of the proposed action, mitigation measures and monitoring plans, possible future developmental activities at the Heber anomaly, and regulations and permit requirements. (MHR)

Not Available

1980-10-01

348

Free-energy dependence of the rate of electron transfer to the primary quinone in beta-type reaction centers  

NASA Astrophysics Data System (ADS)

Reaction centers of the beta-type mutants, (M)L214H and (M)L214H/(L)E104V, which contain a bacteriochlorophyll (denoted ?) in place of the photoactive bacteriopheophytin, have been depleted of the native ubiquinone and reconstituted with a number of quinones. This system has allowed investigation of the rate versus free-energy relationship for electron transfer to the primary quinone in the activationless and inverted regions. The dependence of the rate on driving force is found to be much weaker in both mutants than in wild-type RCs. Analysis of the data using electron transfer theory shows that the essentially flat dependence of rate on free energy for the quinone-reconstituted beta-type mutants cannot be explained simply on the basis of increased driving force, but additionally requires a decrease in the reorganization energy. A decreased reorganization energy most likely derives from a change in the nature of the intermediary electron carrier in the mutants compared to wild-type RCs, in particular the involvement of the accessory bacteriochlorophyll molecule BChl L. The weak free-energy and temperature dependence of the electron transfer process are consistent with coupling to a range of high- to low-frequency vibrational modes of the cofactors and protein.

Laporte, Laurent; Kirmaier, Christine; Schenck, Craig C.; Holten, Dewey

1995-08-01

349

Variable Sun-Earth energy coupling function: dependence on solar cycle strength  

NASA Astrophysics Data System (ADS)

Correlation between monthly geomagnetic activity and monthly sunspot numbers for more than 50 years revealed that the geomagnetic activity during the current solar maximum is lower than what can be expected from the sunspot numbers. This is valid for both one station (Kiruna K index, since 1962) and world-wide average (Kp index, since 1932). The Kp data with more than 80 years record also revealed that monthly Kp for given sunspot numbers are lower during solar cycles with small amplitude than those with large amplitude when we define the cycle from the end of solar maximum to the end of next solar maximum. The result suggests that the Sun-Earth coupling function itself (including the multiplication constant) might be different between different solar cycles when the amplitude is different, and therefore that there might be unknown solar parameter that should contribute to the Sun-Earth coupling. Such a hidden parameter might bridge missing physical link between the solar effect and the terrestrial environment such as the global temperature. Acknowledgement: Kp is an official IAGA endorsed index that is provided by GFZ, Adolf-Schmidt-Observatory Niemegk, Germany. The sunspot numbers are provided by Royal Observatory of Belgium, Brussels.

Yamauchi, Masatoshi

2014-05-01

350

Life Cycle Assessment of the Energy Independence and Security Act of 2007: Ethanol - Global Warming Potential and Environmental Emissions  

SciTech Connect

The objective of this study is to use life cycle assessment (LCA) to evaluate the global warming potential (GWP), water use, and net energy value (NEV) associated with the EISA-mandated 16 bgy cellulosic biofuels target, which is assumed in this study to be met by cellulosic-based ethanol, and the EISA-mandated 15 bgy conventional corn ethanol target. Specifically, this study compares, on a per-kilometer-driven basis, the GWP, water use, and NEV for the year 2022 for several biomass feedstocks.

Heath, G. A.; Hsu, D. D.; Inman, D.; Aden, A.; Mann, M. K.

2009-07-01

351

Specification and implementation of IFC based performance metrics to support building life cycle assessment of hybrid energy systems  

SciTech Connect

Minimizing building life cycle energy consumption is becoming of paramount importance. Performance metrics tracking offers a clear and concise manner of relating design intent in a quantitative form. A methodology is discussed for storage and utilization of these performance metrics through an Industry Foundation Classes (IFC) instantiated Building Information Model (BIM). The paper focuses on storage of three sets of performance data from three distinct sources. An example of a performance metrics programming hierarchy is displayed for a heat pump and a solar array. Utilizing the sets of performance data, two discrete performance effectiveness ratios may be computed, thus offering an accurate method of quantitatively assessing building performance.

Morrissey, Elmer; O'Donnell, James; Keane, Marcus; Bazjanac, Vladimir

2004-03-29

352

Building Energy Use and Conservation in Cycle VIII of the Texas Institutional Conservation Program  

E-print Network

energy saving measures. Such measures include both maintenance and operation (H&O) measures (generally regarded as "low-cost, no-cost") and energy conservation (ECH) measures (generally more expensive and requiring outside skills). Implementation cost...

Schrecengost, R. C.; Lum, S. K.; Notman, J. R.; Sattler, D. R.; Heffington, W. M.

1986-01-01

353

System Architecture of Explorer Class Spaceborne Telescopes: A look at Optimization of Cost, Testability, Risk and Operational Duty Cycle from the Perspective of Primary Mirror Material Selection  

NASA Astrophysics Data System (ADS)

Management of cost and risk have become the key enabling elements for compelling science to be done within Explorer or M-Class Missions. We trace how optimal primary mirror selection may be co-optimized with orbit selection. And then trace the cost and risk implications of selecting a low diffusivity low thermal expansion material for low and medium earth orbits, vs. high diffusivity high thermal expansion materials for the same orbits. We will discuss that ZERODUR®, a material that has been in space for over 30 years, is now available as highly lightweighted open-back mirrors, and the attributes of these mirrors in spaceborne optical telescope assemblies. Lightweight ZERODUR® solutions are practical from mirrors < 0.3m in diameter to >4m in diameter. An example of a 1.2m lightweight ZERODUR® mirror will be discussed.

Hull, Anthony B.; Westerhoff, Thomas

2015-01-01

354

Life cycle cost analysis of a multi-storey residential Net Zero Energy Building in Denmark  

Microsoft Academic Search

It is well recognized that in the long run, the implementation of energy efficiency measures is a more cost-optimal solution in contrast to taking no action. However, the Net ZEB concept raises a new issue: how far should we go with energy efficiency measures and when should we start to apply renewable energy technologies? This analysis adopts the LCC methodology

Anna Joanna Marszal; Per Heiselberg

2011-01-01

355

Energy and labor costs of alternative coal-electric fuel cycles. [Comparison of eastern vs. western  

Microsoft Academic Search

In making decisions concerning the generation of electricity, Midwestern power companies should consider other factors beyond dollar costs, including the energy and labor impacts of a power-generation decision. This report investigates the comparative net energy, job, and dollar costs of burning western and eastern coal in a fictitious Chicago power plant to produce 1000 kWh of electricity. The energy and

J. Kurish; P. Penner; B. Hannon

1981-01-01

356

Review of Life-Cycle Approaches Coupled with Data Envelopment Analysis: Launching the CFP + DEA Method for Energy Policy Making  

PubMed Central

Life-cycle (LC) approaches play a significant role in energy policy making to determine the environmental impacts associated with the choice of energy source. Data envelopment analysis (DEA) can be combined with LC approaches to provide quantitative benchmarks that orientate the performance of energy systems towards environmental sustainability, with different implications depending on the selected LC + DEA method. The present paper examines currently available LC + DEA methods and develops a novel method combining carbon footprinting (CFP) and DEA. Thus, the CFP + DEA method is proposed, a five-step structure including data collection for multiple homogenous entities, calculation of target operating points, evaluation of current and target carbon footprints, and result interpretation. As the current context for energy policy implies an anthropocentric perspective with focus on the global warming impact of energy systems, the CFP + DEA method is foreseen to be the most consistent LC + DEA approach to provide benchmarks for energy policy making. The fact that this method relies on the definition of operating points with optimised resource intensity helps to moderate the concerns about the omission of other environmental impacts. Moreover, the CFP + DEA method benefits from CFP specifications in terms of flexibility, understanding, and reporting. PMID:25654136

Vázquez-Rowe, Ian

2015-01-01

357

Energy and emission benefits of alternative transportation liquid fuels derived from switchgrass: a fuel life cycle assessment.  

PubMed

We conducted a mobility chains, or well-to-wheels (WTW), analysis to assess the energy and emission benefits of cellulosic biomass for the U.S. transportation sector in the years 2015-2030. We estimated the life-cycle energy consumption and emissions associated with biofuel production and use in light-duty vehicle (LDV) technologies by using the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model. Analysis of biofuel production was based on ASPEN Plus model simulation of an advanced fermentation process to produce fuel ethanol/protein, a thermochemical process to produce Fischer-Tropsch diesel (FTD) and dimethyl ether (DME), and a combined heat and power plant to co-produce steam and electricity. Our study revealed that cellulosic biofuels as E85 (mixture of 85% ethanol and 15% gasoline by volume), FTD, and DME offer substantial savings in petroleum (66-93%) and fossil energy (65-88%) consumption on a per-mile basis. Decreased fossil fuel use translates to 82-87% reductions in greenhouse gas emissions across all unblended cellulosic biofuels. In urban areas, our study shows net reductions for almost all criteria pollutants, with the exception of carbon monoxide (unchanged), for each of the biofuel production option examined. Conventional and hybrid electric vehicles, when fueled with E85, could reduce total sulfur oxide (SO(x)) emissions to 39-43% of those generated by vehicles fueled with gasoline. By using bio-FTD and bio-DME in place of diesel, SO(x) emissions are reduced to 46-58% of those generated by diesel-fueled vehicles. Six different fuel production options were compared. This study strongly suggests that integrated heat and power co-generation by means of gas turbine combined cycle is a crucial factor in the energy savings and emission reductions. PMID:16889378

Wu, May; Wu, Ye; Wang, Michael

2006-01-01

358

The problem of optimizing the water chemistry used in the primary coolant circuit of a nuclear power station equipped with VVER reactors under the conditions of longer fuel cycle campaigns and increased capacity of power units  

NASA Astrophysics Data System (ADS)

It is shown that the optimal water chemistry of the primary coolant circuit must be substantiated while introducing measures aimed at increasing the power output in operating power units and for the project called AES-2006/AES TOI (a typical optimized project of a nuclear power station with enhanced information support). The experience gained from operation of PWR reactors with an elongated fuel cycle at an increased level of power is analyzed. Conditions under which boron compounds are locally concentrated on the fuel rod surfaces (the hideout phenomenon) and axial offset anomaly occurs are enlisted, and the influence of lithium on the hideout in the pores of deposits on the surfaces of fuel assemblies is shown.

Sharafutdinov, R. B.; Kharitonova, N. L.

2011-05-01

359

Water Cycle Webquest  

NSDL National Science Digital Library

Students are introduced to the Global Precipitation Measurement (GPM) satellite mission and its role in studying the water cycle. This webquest provides links to eight websites, allowing middle school students to explore the water cycle and its impacts on Earth's weather and climate. Through online videos and articles, students follow a water molecule through the cycle, discover the connection between the water cycle and global water/heat distribution, examine the role of solar energy, and assess the importance of fresh water.

360

Alternative primary energy for power desalting plants in Kuwait: the nuclear option I  

Microsoft Academic Search

Some countries (e.g. Korea, China, India, Pakistan, Japan) were forced to adopt the nuclear energy option to generate electric power Ep (by nuclear power plants NPP) and desalt seawater D (by nuclear desalination ND) due to the rising cost of fossil fuel and its insecure supply. The increase of fuel oil consumption and cost (more than $100 per barrel) motivate

M. A. Darwisha; Fatima M. Al-Awadhi; Ali Akbar; Ali Darwish

2009-01-01

361

Primary Isotope Yields and Characteristic Properties of the Fragmenting Source in Heavy-ion Reactions near the Fermi Energies  

E-print Network

For central collisions of $^{40}$Ca $+ ^{40}$Ca at 35 MeV/nucleon, the density and temperature of a fragmenting source have been evaluated in a self-consistent manner using the ratio of the symmetry energy coefficient relative to the temperature, $a_{sym}/T$, extracted from the yields of primary isotopes produced in antisymmetrized molecular dynamics (AMD) simulations. The $a_{sym}/T$ values are extracted from all isotope yields using an improved method based on the Modified Fisher Model (MFM). The values of $a_{sym}/T$ obtained, using different interactions with different density dependencies of the symmetry energy term, are correlated with the values of the symmetry energies at the density of fragment formation. Using this correlation, the fragment formation density is found to be $\\rho/\\rho_0 = 0.67 \\pm 0.02$. Using the input symmetry energy value for each interaction temperature values are extracted as a function of isotope mass $A$. The extracted temperature values are compared with those evaluated from the fluctuation thermometer with a radial flow correction.

X. Liu; W. Lin; R. Wada; M. Huang; Z. Chen; G. Q. Xiao; S. Zhang; X. Jin; J. Liu; F. Shi; P. Ren; H. Zheng; J. B. Natowitz; A. Bonasera

2014-04-23

362

Primary isotope yields and characteristic properties of the fragmenting source in heavy-ion reactions near the Fermi energy  

NASA Astrophysics Data System (ADS)

For central collisions of Ca40+Ca40 at 35 MeV/nucleon, the density and temperature of a fragmenting source have been evaluated in a self-consistent manner using the ratio of the symmetry energy coefficient relative to the temperature, asym/T, extracted from the yields of primary isotopes produced in antisymmetrized molecular dynamics (AMD) simulations. The asym/T values are extracted from all isotope yields using an improved method based on the modified Fisher model (MFM). The values of asym/T obtained, using different interactions with different density dependencies of the symmetry energy term, are correlated with the values of the symmetry energies at the density of fragment formation. Using this correlation, the fragment formation density is found to be ? /?0=0.67±0.02. Using the input symmetry energy value for each interaction temperature values are extracted as a function of isotope mass A. The extracted temperature values are compared with those evaluated from the fluctuation thermometer with a radial flow correction.

Liu, X.; Lin, W.; Wada, R.; Huang, M.; Chen, Z.; Xiao, G. Q.; Zhang, S.; Jin, X.; Han, R.; Liu, J.; Shi, F.; Zheng, H.; Natowitz, J. B.; Bonasera, A.

2014-07-01

363

Managing forests for biomass energy and nutrient-cycling concerns in the Atlantic coastal plain  

SciTech Connect

A model of nitrogen cycling for the system described by Koch (1980) predicted a nitrogen deficit for loblolly pine (Pinus taeda) during the second rotation. Rates of availability fell below needs primarily due to 662 kg/ha depletion of soil organic nitrogen. The most critical assumption made in the model was the rate of soil organic nitrogen availability. Comparisons of nitrogen utilization efficiency (kg biomass/kg N) showed slow growing conifers on poor sites were the most efficient systems. Productivity efficiency (kg/ha/yr/kg N) indicated that if the amount of available land is limited, short rotations of loblolly pine or eastern cottonwood (Populus deltoides) should be emphasized.

Williams, T.M.; Gresham, C.A.

1982-01-01

364

NV Energy Solar Integration Study: Cycling and Movements of Conventional Generators for Balancing Services  

SciTech Connect

With an increasing penetration level of solar power in the southern Nevada system, the impact of solar on system operations needs to be carefully studied from various perspectives. Qualitatively, it is expected that the balancing requirements to compensate for solar power variability will be larger in magnitude; meanwhile, generators providing load following and regulation services will be moved up or down more frequently. One of the most important tasks is to quantitatively evaluate the cycling and movements of conventional generators with solar power at different penetration levels. This study is focused on developing effective methodologies for this goal and providing a basis for evaluating the wear and tear of the conventional generators

Diao, Ruisheng; Lu, Shuai; Etingov, Pavel V.; Ma, Jian; Makarov, Yuri V.; Guo, Xinxin

2011-07-01

365

Uncertainty propagation in life cycle assessment of biodiesel versus diesel: global warming and non-renewable energy.  

PubMed

Uncertainty information is essential for the proper use of life cycle assessment and environmental assessments in decision making. To investigate the uncertainties of biodiesel and determine the level of confidence in the assertion that biodiesel is more environmentally friendly than diesel, an explicit analytical approach based on the Taylor series expansion for lognormal distribution was applied in the present study. A biodiesel case study demonstrates the probability that biodiesel has a lower global warming and non-renewable energy score than diesel, that is 92.3% and 93.1%, respectively. The results indicate the level of confidence in the assertion that biodiesel is more environmentally friendly than diesel based on the global warming and non-renewable energy scores. PMID:22178489

Hong, Jinglan

2012-06-01

366

Comparison of life cycle carbon dioxide emissions and embodied energy in four renewable electricity generation technologies in New Zealand.  

PubMed

In order to make the best choice between renewable energy technologies, it is important to be able to compare these technologies on the basis of their sustainability, which may include a variety of social, environmental, and economic indicators. This study examined the comparative sustainability of four renewable electricity technologies in terms of their life cycle CO2 emissions and embodied energy, from construction to decommissioning and including maintenance (periodic component replacement plus machinery use), using life cycle analysis. The models developed were based on case studies of power plants in New Zealand, comprising geothermal, large-scale hydroelectric, tidal (a proposed scheme), and wind-farm electricity generation. The comparative results showed that tidal power generation was associated with 1.8 g of CO2/kWh, wind with 3.0 g of CO2/kWh, hydroelectric with 4.6 g of CO2/kWh, and geothermal with 5.6 g of CO2/kWh (not including fugitive emissions), and that tidal power generation was associated with 42.3 kJ/kWh, wind with 70.2 kJ/kWh, hydroelectric with 55.0 kJ/kWh, and geothermal with 94.6 kJ/kWh. Other environmental indicators, as well as social and economic indicators, should be applied to gain a complete picture of the technologies studied. PMID:19746744

Rule, Bridget M; Worth, Zeb J; Boyle, Carol A

2009-08-15

367

University of Minnesota aquifer thermal energy storage (ATES) project report on the third long-term cycle  

SciTech Connect

The University of Minnesota aquifer thermal energy storage (ATES) system has been operated as a field test facility (FTF) since 1982. The objectives were to design, construct, and operate the facility to study the feasibility of high-temperature ATES in a confined aquifer. Four short-term and two long-term cycles were previously conducted, which provided a greatly increased understanding of the efficiency and geochemical effects of high-temperature aquifer thermal energy storage. The third long-term cycle (LT3) was conducted to operate the ATES system in conjunction with a real heating load and to further study the geochemical impact that heated water storage had on the aquifer. For LT3, the source and storage wells were modified so that only the most permeable portion, the Ironton-Galesville part, of the Franconia-Ironton-Galesville aquifer was used for storage. This was expected to improve storage efficiency by reducing the surface area of the heated volume and simplify analysis of water chemistry results by reducing the number of aquifer-related variables which need to be considered. During LT3, a total volume of 63.2 {times} 10{sup 3} m {sup 3} of water was injected at a rate of 54.95 m{sup 3}/hr into the storage well at a mean temperature of 104.7{degrees}C. Tie-in to the reheat system of the nearby Animal Sciences Veterinary Medicine (ASVM) building was completed after injection was completed. Approximately 66 percent (4.13 GWh) of the energy added to the aquifer was recovered. Approximately 15 percent (0.64 GWh) of the usable (10 building. Operations during heat recovery with the ASVM building`s reheat system were trouble-free. Integration into more of the ASVM (or other) building`s mechanical systems would have resulted in significantly increasing the proportion of energy used during heat recovery.

Hoyer, M.C.; Hallgren, J.P.; Uebel, M.H.; Delin, G.N.; Eisenreich, S.J.; Sterling, R.L.

1994-12-01

368

A comparison of muscular mechanical energy expenditure and internal work in cycling  

Microsoft Academic Search

The hypothesis that the sum of the absolute changes in mechanical energy (internal work) is correlated with the muscular mechanical energy expenditure (MMEE) was tested using two elliptical chainrings, one that reduced and one that increased the internal work (compared to circular). Upper and lower bounds were put on the extra MMEE (work done by net joint torques in excess

S. A. Kautz; M. L. HULLS; R. R. Neptune

1994-01-01

369

Life-cycle-assessment of fuel-cells-based landfill-gas energy conversion technologies  

Microsoft Academic Search

Landfill-gas (LFG) is produced as result of the biological reaction of municipal solid waste (MSW). This gas contains about 50% of methane, therefore it cannot be released into the atmosphere as it is because of its greenhouse effect consequences. The high percentage of methane encouraged researchers to find solutions to recover the related energy content for electric energy production. The

P. Lunghi; R. Bove; U. Desideri

2004-01-01

370

A new model of the global biogeochemical cycle of carbonyl sulfide - Part 2: Use of ocs to constrain gross primary productivity of current vegetation models  

NASA Astrophysics Data System (ADS)

Clear analogies between carbonyl sulfide (OCS) and carbon dioxide (CO2) diffusion pathways through leaves have been revealed by experimental studies with plant uptake playing an important role for the atmospheric budget of both species. Here we use atmospheric OCS to evaluate the gross primary production (GPP) of three dynamic global vegetation models (LPJ, NCAR-CLM4 and ORCHIDEE). Vegetation uptake of OCS is modeled as a linear function of GPP and LRU, the ratio of OCS to CO2 deposition velocities to plants. New parameterizations for the non-photosynthetic sinks (oxic soils, atmospheric oxidation) and biogenic sources (oceans and anoxic soils) of OCS are also provided. Despite new large oceanic emissions, global OCS budgets created with each vegetation model show exceeding sinks by several hundreds of Gg S yr-1. An inversion of the surface fluxes (optimization of a global scalar which accounts for flux uncertainties) led to balanced OCS global budgets, as atmospheric measurements suggest, mainly by drastic reduction (-30%) of soil and vegetation uptakes. The amplitude of variations in atmospheric OCS mixing ratios is mainly dictated by the vegetation sink over the Northern Hemisphere. This allows for bias recognition in the GPP representations of the three selected models. Main bias patterns are (i) the terrestrial GPP of ORCHIDEE at high Northern latitudes is currently over-estimated, (ii) the seasonal variations of the GPP are out of phase in the NCAR-CLM4 model, showing a maximum carbon uptake too early in spring in the northernmost ecosystems, (iii) the overall amplitude of the seasonal variations of GPP in NCAR-CLM4 is too small, and (iv) for the LPJ model, the GPP is slightly out of phase for northernmost ecosystems and the respiration fluxes might be too large in summer in the Northern Hemisphere.

Launois, T.; Peylin, P.; Belviso, S.; Poulter, B.

2014-11-01

371

The effects of energy paths and emission controls and standards on future trends in China's emissions of primary air pollutants  

NASA Astrophysics Data System (ADS)

To examine the efficacy of China's actions to control atmospheric pollution, three levels of growth of energy consumption and three levels of implementation of emission controls are estimated, generating a total of nine combined activity-emission control scenarios that are then used to estimate trends of national emissions of primary air pollutants through 2030. The emission control strategies are expected to have more effects than the energy paths on the future emission trends for all the concerned pollutants. As recently promulgated national action plans of air pollution prevention and control (NAPAPPC) are implemented, China's anthropogenic pollutant emissions should decline. For example, the emissions of SO2, NOx, total primary particulate matter (PM), PM10, and PM2.5 are estimated to decline 7%, 20%, 41%, 34%, and 31% from 2010 to 2030, respectively, in the "best guess" scenario that includes national commitment of energy saving policy and partial implementation of NAPAPPC. Should the issued/proposed emission standards be fully achieved, a less likely scenario, annual emissions would be further reduced, ranging from 17% (for primary PM2.5) to 29% (for NOx) declines in 2015, and the analogue numbers would be 12% and 24% in 2030. The uncertainties of emission projections result mainly from the uncertain operational conditions of swiftly proliferating air pollutant control devices and lack of detailed information about emission control plans by region. The predicted emission trends by sector and chemical species raise concerns about current pollution control strategies: the potential for emissions abatement in key sectors may be declining due to the near saturation of emission control devices use; risks of ecosystem acidification could rise because emissions of alkaline base cations may be declining faster than those of SO2; and radiative forcing could rise because emissions of positive-forcing carbonaceous aerosols may decline more slowly than those of SO2 emissions and thereby concentrations of negative-forcing sulfate particles. Expanded control of emissions of fine particles and carbonaceous aerosols from small industrial and residential sources is recommended, and a more comprehensive emission control strategy targeting a wider range of pollutants and taking account of more diverse environmental impacts is also urgently needed.

Zhao, Y.; Zhang, J.; Nielsen, C. P.

2014-03-01

372

Accelerated cycle life testing of lead-acid golf car batteries and the influence of separator type on battery life, energy consumption and operating cost  

NASA Astrophysics Data System (ADS)

Commercial lead-acid golf car batteries containing five different separator materials were cycle life tested. An accelerated cycle life test was employed in which the battery temperature was allowed to rise as the batteries became less efficient in power utilization towards the end of life, and there was no rest period between charge and discharge during cycling. The effects of continuous cycling and separator type on battery performance were monitored throughout the test together with battery temperature, end of charge current, energy balances, and capacity. Cycle life test data through correlation with actual expected life in the field allowed calculations to be made to determine the relative effective operating cost of various battery types. The battery made with FLEX-SIL® rubber separators exhibited the best life and economics when compared with batteries containing ACE-SILC® rubber, polyethylene, cellulose (paper), and sintered PVC separators.

Goldberg, Bruce S.; Hausser, Alexander G.; Le, Bich T.

373

The Use of History and Philosophy of Science as a Core for a Socioconstructivist Teaching Approach of the Concept of Energy in Primary Education  

ERIC Educational Resources Information Center

The present study should be thought as a socioconstructivist teaching approach (a teaching model) for the concept of energy in primary education. It contains important and crucial aspects of the History and Philosophy of Natural Sciences, introduces the concept of energy using the macroscopic framework of thermodynamics, takes into consideration…

Rizaki, Aikaterini; Kokkotas, Panagiotis

2013-01-01

374

Preexercise energy drink consumption does not improve endurance cycling performance but increases lactate, monocyte, and interleukin-6 response.  

PubMed

The purpose of this study was to investigate the influence of an energy drink (ED) on cycling performance and immune-related variables. Eleven trained male cyclists (33.4 ± 8.9 years; 81 ± 7.6 kg; maximal VO2, 52 ± 3.4 ml·kg(-1)·min(-1)) consumed 500 ml of (a) ED (2.0 g taurine, 1.2 g glucuronolactone, 160 mg caffeine, 56 g carbohydrate [CHO], and B vitamins), (b) cola matched for caffeine and CHO (CC), or (c) flavored placebo (PL: sparking water and flavoring) 50 minutes before racing in a randomized, crossover design. Performance was measured as time to complete (TTC) a 25-mile simulated road race. Blood was collected at baseline, 30 minutes after drink consumption, during exercise at miles 5 (M5), 15 (M15), and immediately (POEX) and 30 minutes (30minPO) after exercise. TTC was not different (p > 0.05) among trials (ED, 68.6 ± 2.7; CC, 68.9 ± 3.8; PL, 69.6 ± 3.8 minutes). Consumption of CC and ED elicited a mild hypoglycemia elicited a mild hypoglycemia during cycling. POEX interleukin-6 (IL-6) was greatest after ED, whereas CC IL-6 was greater than PL (10.2 ± 1.6, 6.7 ± 0.6, and 4.8 ± 0.7 pg·ml(-1), respectively; p < 0.001). Cycling increased leukocyte number in all conditions with ED leukocyte number greater than that of PL at M15 (9.8 ± 0.6, 8.5 ± 0.3 × 10(6) cells·mL(-1)). Energy drink induced an earlier recruitment of monocytes to the blood stream than CC. Mean fat oxidation was greater in PL compared with CC (0.43 ± 0.06 and 0.28 ± 0.04 g·min(-1); p = 0.033) but did not differ between ED (0.32 ± 0.06) and PL. Lactate was higher in ED compared with CC and PL at M5 and M15 (p = 0.003), but there was no significant influence of either ED or CC on performance. Carbohydrate and caffeine consumption before endurance cycling significantly increased the IL-6 release and leukocytosis, and the additional ingredients in ED seem to have further augmented these responses. PMID:24172719

Phillips, Melody D; Rola, Kelyn S; Christensen, Kenneth V; Ross, Jacob W; Mitchell, Joel B

2014-05-01

375

Energy harvesting from self-sustained aeroelastic limit cycle oscillations of rectangular wings  

NASA Astrophysics Data System (ADS)

Three different aspect-ratio rectangular wings are designed and experimentally tested to produce self-sustained aeroelastic oscillations for energy harvesting via implementing a piezoelectric generator. Sensitivity measurements are conducted first to determine the critical conditions producing such oscillations with a dominant frequency of 1 Hz. Furthermore, the energy harvesting performance is maximized as the piezoelectric generator is implemented in parallel with oncoming flow streamline. Approximately 55 mW electricity is produced from a wing with a surface area of 0.025 m2. Unlike conventional wind turbine technology, the present work opens up another possible way to harvest energy via nonlinear aeroelastic oscillations.

Zhao, Dan; Ega, Evan

2014-09-01

376

The Use of History and Philosophy of Science as a Core for a Socioconstructivist Teaching Approach of the Concept of Energy in Primary Education  

NASA Astrophysics Data System (ADS)

The present study should be thought as a socioconstructivist teaching approach (a teaching model) for the concept of energy in primary education. It contains important and crucial aspects of the History and Philosophy of Natural Sciences, introduces the concept of energy using the macroscopic framework of thermodynamics, takes into consideration learners' alternative ideas or frameworks relating to energy, takes advantage of the causal and the unifying characters of energy, which have been founded on the historiographical analysis of this concept, uses energy chains as visual representations for the deep understanding of it, uses visual grammar of Kress and van Leeuwen to design energy chains and introduces a teaching methodology for this concept.

Rizaki, Aikaterini; Kokkotas, Panagiotis

2013-05-01

377

Effects of ethanol on vehicle energy efficiency and implications on ethanol life-cycle greenhouse gas analysis.  

PubMed

Bioethanol is the world's largest-produced alternative to petroleum-derived transportation fuels due to its compatibility within existing spark-ignition engines and its relatively mature production technology. Despite its success, questions remain over the greenhouse gas (GHG) implications of fuel ethanol use with many studies showing significant impacts of differences in land use, feedstock, and refinery operation. While most efforts to quantify life-cycle GHG impacts have focused on the production stage, a few recent studies have acknowledged the effect of ethanol on engine performance and incorporated these effects into the fuel life cycle. These studies have broadly asserted that vehicle efficiency increases with ethanol use to justify reducing the GHG impact of ethanol. These results seem to conflict with the general notion that ethanol decreases the fuel efficiency (or increases the fuel consumption) of vehicles due to the lower volumetric energy content of ethanol when compared to gasoline. Here we argue that due to the increased emphasis on alternative fuels with drastically differing energy densities, vehicle efficiency should be evaluated based on energy rather than volume. When done so, we show that efficiency of existing vehicles can be affected by ethanol content, but these impacts can serve to have both positive and negative effects and are highly uncertain (ranging from -15% to +24%). As a result, uncertainties in the net GHG effect of ethanol, particularly when used in a low-level blend with gasoline, are considerably larger than previously estimated (standard deviations increase by >10% and >200% when used in high and low blends, respectively). Technical options exist to improve vehicle efficiency through smarter use of ethanol though changes to the vehicle fleets and fuel infrastructure would be required. Future biofuel policies should promote synergies between the vehicle and fuel industries in order to maximize the society-wise benefits or minimize the risks of adverse impacts of ethanol. PMID:23627549

Yan, Xiaoyu; Inderwildi, Oliver R; King, David A; Boies, Adam M

2013-06-01

378

Conceptual design of an Open-Cycle Ocean Thermal Energy Conversion Net Power-Producing Experiment (OC-OTEC NPPE)  

NASA Astrophysics Data System (ADS)

This report describes the conceptual design of an experiment to investigate heat and mass transfer and to assess the viability of open-cycle ocean thermal energy conversion (OC-OTEC). The experiment will be developed in two stages, the Heat- and Mass-Transfer Experimental Apparatus (HMTEA) and the Net Power-Producing Experiment (NPPE). The goal for the HMTEA is to test heat exchangers. The goal for the NPPE is to experimentally verify OC-OTEC's feasibility by installing a turbine and testing the power-generating system. The design effort met the goals of both the HMTEA and the NPPE, and duplication of hardware was minimal. The choices made for the design resource water flow rates are consistent with the availability of cold and warm seawater as a result of the seawater systems upgrade carried out by the U.S. Department of Energy (DOE), the state of Hawaii, and the Pacific International Center for High Technology Research. The choices regarding configuration of the system were made based on projected performance, degree of technical risk, schedule, and cost. The cost for the future phase of the design and the development of the HMTEA/NPPE is consistent with the projected future program funding levels. The HMTEA and NPPE were designed cooperatively by PICHTR, Argonne National Laboratory, and Solar Energy Research Institute under the guidance of DOE. The experiment will be located at the DOE's Seacoast Test Facility at the Natural Energy Laboratory of Hawaii, Kailua-Kona, Hawaii.

Bharathan, D.; Green, H. J.; Link, H. F.; Parsons, B. K.; Parsons, J. M.; Zangrando, F.

1990-07-01

379

Second Law Analysis for Process and Energy Engineering: Use in a Steam/Power Cycle  

E-print Network

exergy value per unit of heat CQuid have been used. e. Using fuel to heat the entering combustion air, which Is at ambient temperature. The foregoing observations are qualitative rather than quantitative, and even without quantification they can... not -- the 2nd law concept, exergy, does .- represent ?potentlal to cause change: Nevertheless, energy is an important scientific concept. It Is a key to the modelling of natural phenomena and systems. (By no means do we advocate replacing ?energy analysis...

Sama, D.; Sanhong, Q.

380

Primary Syphilis  

MedlinePLUS

newsletter | contact Share | Primary Syphilis Information for adults A A A This image displays a painless ulcer with a red base, typical of primary syphilis. Overview Primary syphilis is a disease caused by ...

381

Open-cycle desiccant air conditioning as an alternative to vapor compression cooling in residential applications  

Microsoft Academic Search

The performance of open-cycle desiccant air conditioners for residential applications is evaluated. The performance of these systems is compared to that of vapor compression air conditioners on the basis of primary energy use and cost. Systems with improved dehumidifiers can achieve seasonal COP's on the order of 1.1. These systems, when coupled with a solar energy system to supply regeneration

J. J. Jurinak; W. A. Beckman; J. W. Mitchell

1984-01-01

382

Thermally regenerative hydrogen/oxygen fuel cell power cycles  

NASA Technical Reports Server (NTRS)

Two innovative thermodynamic power cycles are analytically examined for future engineering feasibility. The power cycles use a hydrogen-oxygen fuel cell for electrical energy production and use the thermal dissociation of water for regeneration of the hydrogen and oxygen. The TDS (thermal dissociation system) uses a thermal energy input at over 2000 K to thermally dissociate the water. The other cycle, the HTE (high temperature electrolyzer) system, dissociates the water using an electrolyzer operating at high temperature (1300 K) which receives its electrical energy from the fuel cell. The primary advantages of these cycles is that they are basically a no moving parts system, thus having the potential for long life and high reliability, and they have the potential for high thermal efficiency. Both cycles are shown to be classical heat engines with ideal efficiency close to Carnot cycle efficiency. The feasibility of constructing actual cycles is investigated by examining process irreversibilities and device efficiencies for the two types of cycles. The results show that while the processes and devices of the 2000 K TDS exceed current technology limits, the high temperature electrolyzer system appears to be a state-of-the-art technology development. The requirements for very high electrolyzer and fuel cell efficiencies are seen as determining the feasbility of the HTE system, and these high efficiency devices are currently being developed. It is concluded that a proof-of-concept HTE system experiment can and should be conducted.

Morehouse, J. H.

1986-01-01

383

Direct energy recovery from primary and secondary sludges by supercritical water oxidation.  

PubMed

Supercritical water oxidation (SCWO) oxidizes organic and biological materials virtually completely to benign products without the need for stack gas scrubbing. Heavy metals are recovered as stabilized solid, along with the sand and clay that is present in the feed. The technology has been under development for twenty years. The major obstacle to commercialization has been developing reactors that are not clogged by inorganic solid deposits. That problem has been solved by using tubular reactors with fluid velocities that are high enough to keep solids in suspension. Recently, system designs have been created that reduce the cost of processing sewage sludges below that of incineration. At 10 wt- % dry solids, sludge can be oxidized with virtually complete recovery of the sludge heating value as hot water or high-pressure steam. Liquid carbon dioxide of high purity can be recovered from the gaseous effluent and excess oxygen can be recovered for recycle. The net effect is to reduce the stack to a harmless vent with minimal flow rate of a clean gas. Complete simulations have been developed using physical property models that accurately simulate the thermodynamic properties of sub- and supercritical water in mixtures with O2, N2, CO2, and organics. Capital and operating cost estimates are given for sewage sludge treatment, which are less costly than incineration. The scenario of direct recovery of energy from sludges has inherent benefits compared to other gasification or liquefaction options. PMID:15259956

Svanström, M; Modell, M; Tester, J

2004-01-01

384

Report of the Fuel Cycle Research and Development Subcommittee of the Nuclear Energy Advisory Committee  

SciTech Connect

The Fuel Cycle (FC) Subcommittee of NEAC met February 7-8, 2012 in Washington (Drs. Hoffmann and Juzaitis were unable to attend). While the meeting was originally scheduled to occur after the submission of the President’s FY 2013 budget, the submission was delayed a week; thus, we could have no discussion on balance in the NE program. The Agenda is attached as Appendix A. The main focus of the meeting was on accident tolerant fuels, an important post Fukushima issue, and on issues related to the report of the Blue Ribbon Commission on America’s Nuclear Future (BRC) as related to the responsibility for used fuel disposal which was assigned to the FC program with the end of the Office of Civilian Radioactive Waste Management. In addition we heard an update on the systems study program which is aimed at helping chose the best options for advanced reactors, and possible new study on separation and waste form relevance to used fuel disposal (these two items are only discussed in this section of the report).

Richter, Burton; Chu, Margaret; Hoffman, Darleane; Juzaitis, Ray; Mtingwa, Sekazi; Omberg, Ronald P.; Rempe, Joy L.; Warin, Dominique

2012-06-12

385

ENERGY DEMANDS AND OTHER ENVIRONMENTAL IMPACTS ACROSS THE LIFE CYCLE OF BIOETHANOL USED AS FUEL  

EPA Science Inventory

Most assessments of converting biomass to fuels are limited to energy and greenhouse gas (GHG) balances to determine if there is a net loss or gain. A fairly consistent conclusion of these studies is that the use of bio-ethanol in place of conventional fuels leads to a net gain....

386

Innovation & Risk Management Result in Energy and Life-Cycle Savings.  

ERIC Educational Resources Information Center

Examines a Pennsylvania school's successful planning, design, and bidding process for acquiring a geothermal heat pump (GHP)system whose subsequent efficiency became award-winning for environmental excellence. Charts and statistical tables describe the GHP's energy savings. Concluding comments review the lessons learned from the process. (GR)

Anstrand, David E.; Singh, J. B.

1999-01-01

387

The effects of energy paths and emission controls and standards on future trends in China's emissions of primary air pollutants  

NASA Astrophysics Data System (ADS)

To examine the efficacy of China's actions to control atmospheric pollution, three levels of growth of energy consumption and three levels of implementation of emission controls are estimated, generating a total of nine combined activity-emission control scenarios that are then used to estimate trends of national emissions of primary air pollutants through 2030. The emission control strategies are expected to have more effects than the energy paths on the future emission trends for all the concerned pollutants. As recently promulgated national action plans of air pollution prevention and control (NAPAPPC) are implemented, China's anthropogenic pollutant emissions should decline. For example, the emissions of SO2, NOx, total suspended particles (TSP), PM10, and PM2.5 are estimated to decline 7, 20, 41, 34, and 31% from 2010 to 2030, respectively, in the "best guess" scenario that includes national commitment of energy saving policy and implementation of NAPAPPC. Should the issued/proposed emission standards be fully achieved, a less likely scenario, annual emissions would be further reduced, ranging from 17 (for primary PM2.5) to 29% (for NOx) declines in 2015, and the analogue numbers would be 12 and 24% in 2030. The uncertainties of emission projections result mainly from the uncertain operational conditions of swiftly proliferating air pollutant control devices and lack of detailed information about emission control plans by region. The predicted emission trends by sector and chemical species raise concerns about current pollution control strategies: the potential for emissions abatement in key sectors may be declining due to the near saturation of emission control devices use; risks of ecosystem acidification could rise because emissions of alkaline base cations may be declining faster than those of SO2; and radiative forcing could rise because emissions of positive-forcing carbonaceous aerosols may decline more slowly than those of SO2 emissions and thereby concentrations of negative-forcing sulfate particles. Expanded control of emissions of fine particles and carbonaceous aerosols from small industrial and residential sources is recommended, and a more comprehensive emission control strategy targeting a wider range of pollutants (volatile organic compounds, NH3 and CO, etc.) and taking account of more diverse environmental impacts is also urgently needed.

Zhao, Y.; Zhang, J.; Nielsen, C. P.

2014-09-01

388

Relative Importance of H2 and H2S as Energy Sources for Primary Production in Geothermal Springs? †  

PubMed Central

Geothermal waters contain numerous potential electron donors capable of supporting chemolithotrophy-based primary production. Thermodynamic predictions of energy yields for specific electron donor and acceptor pairs in such systems are available, although direct assessments of these predictions are rare. This study assessed the relative importance of dissolved H2 and H2S as energy sources for the support of chemolithotrophic metabolism in an acidic geothermal spring in Yellowstone National Park. H2S and H2 concentration gradients were observed in the outflow channel, and vertical H2S and O2 gradients were evident within the microbial mat. H2S levels and microbial consumption rates were approximately three orders of magnitude greater than those of H2. Hydrogenobaculum-like organisms dominated the bacterial component of the microbial community, and isolates representing three distinct 16S rRNA gene phylotypes (phylotype = 100% identity) were isolated and characterized. Within a phylotype, O2 requirements varied, as did energy source utilization: some isolates could grow only with H2S, some only with H2, while others could utilize either as an energy source. These metabolic phenotypes were consistent with in situ geochemical conditions measured using aqueous chemical analysis and in-field measurements made by using gas chromatography and microelectrodes. Pure-culture experiments with an isolate that could utilize H2S and H2 and that represented the dominant phylotype (70% of the PCR clones) showed that H2S and H2 were used simultaneously, without evidence of induction or catabolite repression, and at relative rate differences comparable to those measured in ex situ field assays. Under in situ-relevant concentrations, growth of this isolate with H2S was better than that with H2. The major conclusions drawn from this study are that phylogeny may not necessarily be reliable for predicting physiology and that H2S can dominate over H2 as an energy source in terms of availability, apparent in situ consumption rates, and growth-supporting energy. PMID:18641166

D'Imperio, Seth; Lehr, Corinne R.; Oduro, Harry; Druschel, Greg; Kühl, Michael; McDermott, Timothy R.

2008-01-01

389

Relative importance of H2 and H2S as energy sources for primary production in geothermal springs.  

PubMed

Geothermal waters contain numerous potential electron donors capable of supporting chemolithotrophy-based primary production. Thermodynamic predictions of energy yields for specific electron donor and acceptor pairs in such systems are available, although direct assessments of these predictions are rare. This study assessed the relative importance of dissolved H(2) and H(2)S as energy sources for the support of chemolithotrophic metabolism in an acidic geothermal spring in Yellowstone National Park. H(2)S and H(2) concentration gradients were observed in the outflow channel, and vertical H(2)S and O(2) gradients were evident within the microbial mat. H(2)S levels and microbial consumption rates were approximately three orders of magnitude greater than those of H(2). Hydrogenobaculum-like organisms dominated the bacterial component of the microbial community, and isolates representing three distinct 16S rRNA gene phylotypes (phylotype = 100% identity) were isolated and characterized. Within a phylotype, O(2) requirements varied, as did energy source utilization: some isolates could grow only with H(2)S, some only with H(2), while others could utilize either as an energy source. These metabolic phenotypes were consistent with in situ geochemical conditions measured using aqueous chemical analysis and in-field measurements made by using gas chromatography and microelectrodes. Pure-culture experiments with an isolate that could utilize H(2)S and H(2) and that represented the dominant phylotype (70% of the PCR clones) showed that H(2)S and H(2) were used simultaneously, without evidence of induction or catabolite repression, and at relative rate differences comparable to those measured in ex situ field assays. Under in situ-relevant concentrations, growth of this isolate with H(2)S was better than that with H(2). The major conclusions drawn from this study are that phylogeny may not necessarily be reliable for predicting physiology and that H(2)S can dominate over H(2) as an energy source in terms of availability, apparent in situ consumption rates, and growth-supporting energy. PMID:18641166

D'Imperio, Seth; Lehr, Corinne R; Oduro, Harry; Druschel, Greg; Kühl, Michael; McDermott, Timothy R

2008-09-01

390

Life Cycle Assessment of Carbon Fiber-Reinforced Polymer Composites  

SciTech Connect

Carbon fiber-reinforced polymer matrix composites is gaining momentum with the pressure to lightweight vehicles, however energy-intensity and cost remain some of the major barriers before this material could be used in large-scale automotive applications. A representative automotive part, i.e., a 30.8 kg steel floor pan having a 17% weight reduction potential with stringent cash performance requirements has been considered for the life cycle energy and emissions analysis based on the latest developments occurring in the precursor type (conventional textile-based PAN vs. renewable-based lignin), part manufacturing (conventional SMC vs. P4) and fiber recycling technologies. Carbon fiber production is estimated to be about 14 times more energy-intensive than conventional steel production, however life cycle primary energy use is estimated to be quite similar to the conventional part, i.e., 18,500 MJ/part, especially when considering the uncertainty in LCI data that exists from using numerous sources in the literature. Lignin P4 technology offers the most life cycle energy and CO2 emissions benefits compared to a conventional stamped steel technology. With a 20% reduction in energy use in the lignin conversion to carbon fiber and free availability of lignin as a by-product of ethanol and wood production, a 30% reduction in life cycle energy use could be obtained. A similar level of life cycle energy savings could also be obtained with a higher part weight reduction potential of 43%.

Das, Sujit [ORNL

2011-01-01

391

International nuclear fuel cycle fact book  

SciTech Connect

As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source or information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained has been obtained from nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops; and so forth. Sources do not agree completely with each other, and the data listed herein does not reflect any one single source but frequently is consolidation/combination of information. Lack of space as well as the intent and purpose of the Fact Book limit the given information to that pertaining to the Nuclear Fuel Cycle and to data considered of primary interest or most helpful to the majority of users.

Leigh, I.W.

1988-01-01

392

Energy losses in thermally cycled optical fibers constrained in small bend radii  

SciTech Connect

High energy laser pulses were fired into a 365?m diameter fiber optic cable constrained in small radii of curvature bends, resulting in a catastrophic failure. Q-switched laser pulses from a flashlamp pumped, Nd:YAG laser were injected into the cables, and the spatial intensity profile at the exit face of the fiber was observed using an infrared camera. The transmission of the radiation through the tight radii resulted in an asymmetric intensity profile with one half of the fiber core having a higher peak-to-average energy distribution. Prior to testing, the cables were thermally conditioned while constrained in the small radii of curvature bends. Single-bend, double-bend, and U-shaped eometries were tested to characterize various cable routing scenarios.

Guild, Eric; Morelli, Gregg

2012-09-23

393

Rot it Right: The Cycling of Matter and Transfer of Energy  

NSDL National Science Digital Library

This Immersion Unit provides a coherent series of lessons designed to guide students in developing deep conceptual understanding that is aligned with the National standards, key science concepts, and essential features of classroom inquiry (as defined by the National Science Education Standards). The goal of this unit is to provide students with an opportunity to explore the interdependency of living and nonliving factors in an ecological system. Students investigate the process of decomposition and examine the role that decomposers and other organisms play in the transfer of energy and matter.The Unit's overarching concepts are:Organisms need matter and energy to live.Science knowledge advances through inquiry.This unit was developed through the large Math and Science Partnership project called System-wide Change for All Learners and Educators (SCALE), involving a collaboration among Los Angeles School District educators, California State University science and education faculty, and UW-Madison SCALE staff.

Program, The W.

394

Energy efficiency for the transcritical compression CO2 cycle with the use of the ejector as the first stage of the compression  

NASA Astrophysics Data System (ADS)

An analysis of energy efficiency for transcritical compression unit with CO2 (R744) as the refrigerant has been carried out using empirical operating characteristics for the two-phase ejector. The first stage of the refrigerant compression is carried out in the ejector. The criterion adopted for the estimation of energy efficiency for the cycle is the coefficient of performance COP. The analysis is performed for the heat pump and refrigeration systems. The results of COP for the systems with the ejector has been compared with the COPL values for the single stage Linde cycle.

Kozio?, Joachim; Gazda, Wies?aw; Wil?y?ski, ?ukasz

2010-10-01

395

Gross Primary Productivity  

NASA Technical Reports Server (NTRS)

NASA's new Moderate-resolution Imaging Spectroradiometer (MODIS) allows scientists to gauge our planet's metabolism on an almost daily basis. GPP, gross primary production, is the technical term for plant photosynthesis. This composite image over the continental United States, acquired during the period March 26-April 10, 2000, shows regions where plants were more or less productive-i.e., where they 'inhaled' carbon dioxide and then used the carbon from photosynthesis to build new plant structures. This false-color image provides a map of how much carbon was absorbed out of the atmosphere and fixed within land vegetation. Areas colored blue show where plants used as much as 60 grams of carbon per square meter. Areas colored green and yellow indicate a range of anywhere from 40 to 20 grams of carbon absorbed per square meter. Red pixels show an absorption of less than 10 grams of carbon per square meter and white pixels (often areas covered by snow or masked as urban) show little or no absorption. This is one of a number of new measurements that MODIS provides to help scientists understand how the Earth's landscapes are changing over time. Scientists' goal is use of these GPP measurements to refine computer models to simulate how the land biosphere influences the natural cycles of water, carbon, and energy throughout the Earth system. The GPP will be an integral part of global carbon cycle source and sink analysis, an important aspect of Kyoto Protocol assessments. This image is the first of its kind from the MODIS instrument, which launched in December 1999 aboard the Terra spacecraft. MODIS began acquiring scientific data on February 24, 2000, when it first opened its aperture door. The MODIS instrument and Terra spacecraft are both managed by NASA's Goddard Space Flight Center, Greenbelt, MD. Image courtesy Steven Running, MODIS Land Group Member, University of Montana

2002-01-01

396

Caffeine improves supramaximal cycling but not the rate of anaerobic energy release  

Microsoft Academic Search

The purpose of this study was to determine if improved supramaximal exercise performance in trained cyclists following caffeine\\u000a ingestion was associated with enhanced O2 uptake ($$ \\\\dot{V}{\\\\text{O}}_{2} $$ kinetics), increased anaerobic energy provision (accumulated O2—AO2—deficit), or a reduction in the accumulation of metabolites (for example, K+) associated with muscular fatigue. Six highly trained male cyclists ($$ \\\\dot{V}{\\\\text{O}}_{2} $$peak 68 ± 8 mL kg?1 min?1) performed

Michael J. Simmonds; Clare L. Minahan; Surendran Sabapathy

2010-01-01

397

ENERGY-CYCLE ANALYSIS OF A GASIFICATION-BASED MULTI-PRODUCT SYSTEM WITH CO2 RECOVERY  

Microsoft Academic Search

The DOE is investigating CO2 recovery from fossil-fuel cycles as a greenhouse gas mitigation strategy. Recognizing this, we used life-cycle analysis tools to compare two integrated gasification combined-cycle (IGCC) plant designs based on the Shell entrained-flow gasifier. One option, called the \\

J. C. Molburg; N. F. Brockmeier; V. A. Gorokhov; L. M. Manfredo; M. Ramezan; G. J. Stiegel

398

The Real Biofuel Cycles  

Microsoft Academic Search

This paper analyzes energy efficiency of the industrial corn-ethanol cycle and brackets energy efficiency of the switchgrass-cellulosic ethanol cycle. In particular, it critically evaluates the publications by Farrell et al. (2006a; 2006b) and Shapouri, Wang, et al. (Wang, 2001; Shapouri et al., 2002; Shapouri et al., 2003; Shapouri and McAloon, 2004). It is demonstrated that in a net-energy analysis of

Tad W. Patzek

399

Fictitious Supercontinent Cycles  

NASA Astrophysics Data System (ADS)

"Supercontinent cycles" or "Wilson cycles" is the idea that before Pangaea there were a series of supercontinents that each formed and then broke apart and separated before colliding again, re-aggregating, and suturing into a new supercontinent in a continuing sequence. I suggest that "supercontinent cycles" are artificial constructs, like planetary orbit epicycles, attempts to describe geological phenomena within the framework of problematic paradigms, namely, planetesimal Earth formation and plate tectonics' mantle convection. The so-called 'standard model of solar system formation' is problematic as it would lead to insufficiently massive planetary cores and necessitates additional ad hoc hypotheses such as the 'frost line' between Mars and Jupiter to explain planetary differences and whole-planet melting to explain core formation from essentially undifferentiated matter. The assumption of mantle convection is crucial for plate tectonics, not only for seafloor spreading, but also for continental movement; continent masses are assumed to ride atop convection cells. In plate tectonics, plate collisions are thought to be the sole mechanism for fold-mountain formation. Indeed, the occurrence of mountain chains characterized by folding which significantly predate the breakup of Pangaea is the primary basis for assuming the existence of supercontinent cycles with their respective periods of ancient mountain-forming plate collisions. Mantle convection is physically impossible. Rayleigh Number justification has been misapplied. The mantle bottom is too dense to float to the surface by thermal expansion. Sometimes attempts are made to obviate the 'bottom heavy' prohibition by adopting the tacit assumption that the mantle behaves as an ideal gas with no viscous losses, i.e., 'adiabatic'. But the mantle is a solid that does not behave as an ideal gas as evidenced by earthquakes occurring at depths as great as 660 km. Absent mantle convection, plate tectonics is not valid and there is no motive force for driving supercontinent cycles. The reasonable conclusion one must draw, as in the case of epicycles, is there must exist a new and fundamentally different geoscience paradigm which obviates the problems inherent in plate tectonics and in planetesimal Earth formation and yet better explains geological features. I have disclosed a new indivisible geoscience paradigm, called Whole-Earth Decompression Dynamics (WEDD), that begins with and is the consequence of our planet's early formation as a Jupiter-like gas giant and which permits deduction of: (1) Earth's internal composition and highly-reduced oxidation state; (2) Core formation without whole-planet melting; (3) Powerful new internal energy sources, protoplanetary energy of compression and georeactor nuclear fission energy; (4) Mechanism for heat emplacement at the base of the crust; (5) Georeactor geomagnetic field generation; (6) Decompression-driven geodynamics that accounts for the myriad of observations attributed to plate tectonics without requiring physically-impossible mantle convection, and; (7) A mechanism for fold-mountain formation that does not necessarily require plate collision. The latter obviates the necessity to assume supercontinent cycles. The fundamental basis of geodynamics is this: In response to decompression-driven Earth volume increases, cracks form to increase surface area and mountain ranges characterized by folding form to accommodate changes in curvature. Resources at NuclearPlanet.com .

Marvin Herndon, J.

2014-05-01

400

Energy intensity, life-cycle greenhouse gas emissions, and economic assessment of liquid biofuel pipelines.  

PubMed

Petroleum fuels are predominantly transported domestically by pipelines, whereas biofuels are almost exclusively transported by rail, barge, and truck. As biofuel production increases, new pipelines may become economically attractive. Location-specific variables impacting pipeline viability include construction costs, availability and costs of alternative transportation modes, electricity prices and emissions (if priced), throughput, and subsurface temperature. When transporting alcohol or diesel-like fuels, pipelines have a lower direct energy intensity than rail, barge, and trucks if fluid velocity is under 1 m/s for 4-inch diameter pipelines and 2 m/s for 8-inch or larger pipelines. Across multiple hypothetical state-specific scenarios, profit-maximizing design velocities range from 1.2 to 1.9 m/s. In costs and GHG emissions, optimized pipelines outperform trucks in each state and rail and barge in most states, if projected throughput exceeds four billion liters/year. If emissions are priced, optimum design diameters typically increase to reduce pumping energy demands, increasing the cost-effectiveness of pipeline projects. PMID:24119498

Strogen, Bret; Horvath, Arpad; Zilberman, David

2013-12-01

401

Life-cycle energy use and greenhouse gas emissions of production of bioethanol from sorghum in the United States  

PubMed Central

Background The availability of feedstock options is a key to meeting the volumetric requirement of 136.3 billion liters of renewable fuels per year beginning in 2022, as required in the US 2007 Energy Independence and Security Act. Life-cycle greenhouse gas (GHG) emissions of sorghum-based ethanol need to be assessed for sorghum to play a role in meeting that requirement. Results Multiple sorghum-based ethanol production pathways show diverse well-to-wheels (WTW) energy use and GHG emissions due to differences in energy use and fertilizer use intensity associated with sorghum growth and differences in the ethanol conversion processes. All sorghum-based ethanol pathways can achieve significant fossil energy savings. Relative to GHG emissions from conventional gasoline, grain sorghum-based ethanol can reduce WTW GHG emissions by 35% or 23%, respectively, when wet or dried distillers grains with solubles (DGS) is the co-product and fossil natural gas (FNG) is consumed as the process fuel. The reduction increased to 56% or 55%, respectively, for wet or dried DGS co-production when renewable natural gas (RNG) from anaerobic digestion of animal waste is used as the process fuel. These results do not include land-use change (LUC) GHG emissions, which we take as negligible. If LUC GHG emissions for grain sorghum ethanol as estimated by the US Environmental Protection Agency (EPA) are included (26 g CO2e/MJ), these reductions when wet DGS is co-produced decrease to 7% or 29% when FNG or RNG is used as the process fuel. Sweet sorghum-based ethanol can reduce GHG emissions by 71% or 72% without or with use of co-produced vinasse as farm fertilizer, respectively, in ethanol plants using only sugar juice to produce ethanol. If both sugar and cellulosic bagasse were used in the future for ethanol production, an ethanol plant with a combined heat and power (CHP) system that supplies all process energy can achieve a GHG emission reduction of 70% or 72%, respectively, without or with vinasse fertigation. Forage sorghum-based ethanol can achieve a 49% WTW GHG emission reduction when ethanol plants meet process energy demands with CHP. In the case of forage sorghum and an integrated sweet sorghum pathway, the use of a portion of feedstock to fuel CHP systems significantly reduces fossil fuel consumption and GHG emissions. Conclusions This study provides new insight into life-cycle energy use and GHG emissions of multiple sorghum-based ethanol production pathways in the US. Our results show that adding sorghum feedstocks to the existing options for ethanol production could help in meeting the requirements for volumes of renewable, advanced and cellulosic bioethanol production in the US required by the EPA’s Renewable Fuel Standard program. PMID:24088388

2013-01-01

402

Capital requirements and fuel-cycle energy and emissions impacts of potential PNGV fuels.  

SciTech Connect

Our study reveals that supplying gasoline-equivalent demand for the low-market-share scenario requires a capital investment of less than $40 billion for all fuels except H{sub 2}, which will require a total cumulative investment of $150 billion. By contrast, cumulative capital investments under the high-market-share scenario are $50 billion for LNG, $90 billion for ethanol, $100 billion for methanol, $160 billion for CNG and DME, and $560 billion for H{sub 2}. Although these substantial capital requirements are spread over many years, their magnitude could pose a challenge to the widespread introduction of 3X vehicles. Fossil fuel use by US light-duty vehicles declines significantly with introduction of 3X vehicles because of fuel-efficiency improvements for 3X vehicles and because of fuel substitution (which applies to the nonpetroleum-fueled alternatives). Petroleum use for light-duty vehicles in 2030 is reduced by as much as 45% relative to the reference scenario. GHG emissions follow a similar pattern. Total GHG emissions decline by 25-30% with most of the propulsion system/fuel alternatives. For those using renewable fuels (i.e., ethanol and H{sub 2} from solar energy), GHG emissions drop by 33% (H{sub 2}) and 45% (ethanol). Among urban air pollutants, urban NOX emissions decline slightly for 3X vehicles using CIDI and SIDI engines and drop substantially for fuel-cell vehicles. Urban CO emissions decline for CIDI and FCV alternatives, while VOC emissions drop significantly for all alternatives except RFG-, methanol-, and ethanol-fueled SIDI engines. With the exception of CIDI engines fueled by RFD, FT50, or B20 (which increase urban PM{sub 10} emissions by over 30%), all propulsion system/fuel alternatives reduce urban PM{sub 10} emissions. Reductions are approximately 15-20% for fuel cells and for methanol-, ethanol-, CNG-, or LPG-fueled SIDI engines. Table 3 qualitatively summarizes impacts of the 13 alternatives on capital requirements and on energy use and emissions relative to the reference scenario. The table clearly shows the trade-off between costs and benefits. For example, while H{sub 2} FCVs have the greatest incremental capital needs, they offer the largest energy and emissions benefits. On the basis of the cost and benefit changes shown, methanol and gasoline FCVs appear to have particularly promising benefits-to-costs ratios.

Johnson, L.; Mintz, M.; Singh, M.; Stork, K.; Vyas, A.; Wang, M.

1999-03-11

403

Exposure of Clinical MRSA Heterogeneous Strains to ?-Lactams Redirects Metabolism to Optimize Energy Production through the TCA Cycle  

PubMed Central

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as one of the most important pathogens both in health care and community-onset infections. The prerequisite for methicillin resistance is mecA, which encodes a ?-lactam-insensitive penicillin binding protein PBP2a. A characteristic of MRSA strains from hospital and community associated infections is their heterogeneous expression of resistance to ?-lactam (HeR) in which only a small portion (?0.1%) of the population expresses resistance to oxacillin (OXA) ?10 µg/ml, while in other isolates, most of the population expresses resistance to a high level (homotypic resistance, HoR). The mechanism associated with heterogeneous expression requires both increase expression of mecA and a mutational event that involved the triggering of a ?-lactam-mediated SOS response and related lexA and recA genes. In the present study we investigated the cellular physiology of HeR-MRSA strains during the process of ?-lactam-mediated HeR/HoR selection at sub-inhibitory concentrations by using a combinatorial approach of microarray analyses and global biochemical profiling employing gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS) to investigate changes in metabolic pathways and the metabolome associated with ?-lactam-mediated HeR/HoR selection in clinically relevant heterogeneous MRSA. We found unique features present in the oxacillin-selected SA13011-HoR derivative when compared to the corresponding SA13011-HeR parental strain that included significant increases in tricarboxyl citric acid (TCA) cycle intermediates and a concomitant decrease in fermentative pathways. Inactivation of the TCA cycle enzyme cis-aconitase gene in the SA13011-HeR strain abolished ?-lactam-mediated HeR/HoR selection demonstrating the significance of altered TCA cycle activity during the HeR/HoR selection. These results provide evidence of both the metabolic cost and the adaptation that HeR-MRSA clinical strains undergo when exposed to ?-lactam pressure, indicating that the energy production is redirected to supply the cell wall synthesis/metabolism, which in turn contributes to the survival response in the presence of ?-lactam antibiotics. PMID:23940684

Keaton, Mignon A.; Rosato, Roberto R.; Plata, Konrad B.; Singh, Christopher R.; Rosato, Adriana E.

2013-01-01

404

Study of capacity fade of lithium-ion polymer battery with continuous cycling & power performance modeling of energy storage devices  

NASA Astrophysics Data System (ADS)

Thus far, capacity fade has been ascribed to various mechanisms that include (i) the dissolution of highly resistive surface films on the electrode surface which result from side reactions; (ii) loss in active electrode materials; (iii) phase change in the electrode structure; (iv) loss of electrode contact with the current collector that can lead to complete cell failure. If accurate dynamic prediction models for batteries are to be achieved through the incorporation of the mechanisms of capacity fade, it is important to quantify the contribution of capacity fade to each mechanism. To quantify capacity fade to various mechanism to the overall impedance of the cell, we investigate a complete electrochemical cell for morphological change at the electrode/electrolyte interface and the change in electrode structural after prolong cycling using scanning electron microscopy (SEM), transmission line microscopy (TEM), x-ray diffraction (XRD). Analyses were performed using commercial lithium-ion polymer cell UP383562A (Sony Co.). The electrochemical charge discharge performance was studied using conventional galvanostatic/potentostatic techniques. Fitting techniques using an electrical equivalent circuit was applied to the electrochemical impedance spectra (EIS) using the method of non linear least square fitting (NLLS). Parameter evaluations from the equivalent circuit show that with extended cycling there is a large increase in the impedance of the solid electrolyte impedance, charge transfer resistance and ionic impedance. SEM analysis on the individual electrodes shows that during charge-discharge cycling, thick surface films are deposited on the negative (graphite) electrode surface. These surface films including LiF, Li2CO3 etc. are known to increase the internal impedance of the cell which result in reduce cell performance. No surface films were observed on the cathode (Li1-xCoO 2) electrode surface, however, XRD analysis show the development of some structural defects which are believed to contribute significantly to the overall increase in cell impedance with continuous insertion and extraction of Li ions. The equivalent circuit model obtained from the EIS in the frequency domain can be mapped to a time domain equivalent circuit to accurately represent the dc non-linear behavior, dynamic and transient response of the lithium-ion polymer and electrochemical double layer capacitors (EDLC). More importantly, these models demonstrated that an accurate estimation of the power and energy density relationship in terms of Ragone plots can be obtained.

Moss, Pedro L.

405

Study of the solar anisotropy of cosmic ray primaries of about 200 GeV energy with the L3+C muon detector  

NASA Astrophysics Data System (ADS)

Context: Primary cosmic rays experience multiple deflections in the non-uniform galactic and heliospheric magnetic fields which may generate anisotropies. Aims: A study of anisotropies in the energy range between 100 and 500 GeV is performed. This energy range is not yet well explored. Methods: The L3 detector at the CERN electron-positron collider, LEP, is used for a study of the angular distribution of atmospheric muons with energies above 20 GeV. This distribution is used to investigate the isotropy of the time-dependent intensity of the primary cosmic-ray flux with a Fourier analysis. Results: A small deviation from isotropy at energies around 200 GeV is observed for the second harmonics at the solar frequency. No sidereal anisotropy is found at a level above 10-4. The measurements were performed in the years 1999 and 2000.

L3 Collaboration; Achard, P.; Adriani, O.; Aguilar-Benitez, M.; van den Akker, M.; Alcaraz, J.; Alemanni, G.; Allaby, J.; Aloisio, A.; Alviggi, M. G.; Anderhub, H.; Andreev, V. P.; Anselmo, F.; Arefiev, A.; Azemoon, T.; Aziz, T.; Bagnaia, P.; Bajo, A.; Baksay, G.; Baksay, L.; Bähr, J.; Baldew, S. V.; Banerjee, S.; Banerjee, Sw.; Barczyk, A.; Barillère, R.; Bartalini, P.; Basile, M.; Batalova, N.; Battiston, R.; Bay, A.; Becattini, F.; Becker, U.; Behner, F.; Bellucci, L.; Berbeco, R.; Berdugo, J.; Berges, P.; Bertucci, B.; Betev, B. L.; Biasini, M.; Biglietti, M.; Biland, A.; Blaising, J. J.; Blyth, S. C.; Bobbink, G. J.; Böhm, A.; Boldizsar, L.; Borgia, B.; Bottai, S.; Bourilkov, D.; Bourquin, M.; Braccini, S.; Branson, J. G.; Brochu, F.; Burger, J. D.; Burger, W. J.; Cai, X. D.; Capell, M.; Cara Romeo, G.; Carlino, G.; Cartacci, A.; Casaus, J.; Cavallari, F.; Cavallo, N.; Cecchi, C.; Cerrada, M.; Chamizo, M.; Chang, Y. H.; Chemarin, M.; Chen, A.; Chen, G.; Chen, G. M.; Chen, H. F.; Chen, H. S.; Chiarusi, T.; Chiefari, G.; Cifarelli, L.; Cindolo, F.; Clare, I.; Clare, R.; Coignet, G.; Colino, N.; Costantini, S.; de la Cruz, B.; Cucciarelli, S.; de Asmundis, R.; Déglon, P.; Debreczeni, J.; Degré, A.; Dehmelt, K.; Deiters, K.; della Volpe, D.; Delmeire, E.; Denes, P.; DeNotaristefani, F.; De Salvo, A.; Diemoz, M.; Dierckxsens, M.; Ding, L. K.; Dionisi, C.; Dittmar, M.; Doria, A.; Dova, M. T.; Duchesneau, D.; Duda, M.; Duran, I.; Echenard, B.; Eline, A.; El Mamouni, H.; Engler, A.; Eppling, F. J.; Extermann, P.; Faber, G.; Falagan, M. A.; Falciano, S.; Favara, A.; Fay, J.; Fedin, O.; Felcini, M.; Ferguson, T.; Fiandrini, E.; Field, J. H.; Filthaut, F.; Fisher, W.; Forconi, G.; Freudenreich, K.; Furetta, C.; Galaktionov, Yu.; Ganguli, S. N.; Garcia-Abia, P.; Gataullin, M.; Gentile, S.; Giagu, S.; Gong, Z. F.; Grabosch, H. J.; Grenier, G.; Grimm, O.; Groenstege, H.; Gruenewald, M. W.; Guo, Y. N.; Gupta, S.; Gupta, V. K.; Gurtu, A.; Gutay, L. J.; Haas, D.; Haller, Ch.; Hatzifotiadou, D.; Hayashi, Y.; He, Z. X.; Hebbeker, T.; Hervé, A.; Hirschfelder, J.; Hofer, H.; Hoferjun, H.; Hohlmann, M.; Holzner, G.; Hou, S. R.; Huo, A. X.; Ito, N.; Jin, B. N.; Jindal, P.; Jing, C. L.; Jones, L. W.; de Jong, P.; Josa-Mutuberría, I.; Kantserov, V.; Kaur, M.; Kawakami, S.; Kienzle-Focacci, M. N.; Kim, J. K.; Kirkby, J.; Kittel, W.; Klimentov, A.; König, A. C.; Kok, E.; Korn, A.; Kopal, M.; Koutsenko, V.; Kräber, M.; Kuang, H. H.; Kraemer, R. W.; Krüger, A.; Kuijpers, J.; Kunin, A.; Ladron de Guevara, P.; Laktineh, I.; Landi, G.; Lebeau, M.; Lebedev, A.; Lebrun, P.; Lecomte, P.; Lecoq, P.; Le Coultre, P.; Le Goff, J. M.; Lei, Y.; Leich, H.; Leiste, R.; Levtchenko, M.; Levtchenko, P.; Li, C.; Li, L.; Li, Z. C.; Likhoded, S.; Lin, C. H.; Lin, W. T.; Linde, F. L.; Lista, L.; Liu, Z. A.; Lohmann, W.; Longo, E.; Lu, Y. S.; Luci, C.; Luminari, L.; Lustermann, W.; Ma, W. G.; Ma, X. H.; Ma, Y. Q.; Malgeri, L.; Malinin, A.; Maña, C.; Mans, J.; Martin, J. P.; Marzano, F.; Mazumdar, K.; McNeil, R. R.; Mele, S.; Meng, X. W.; Merola, L.; Meschini, M.; Metzger, W. J.; Mihul, A.; van Mil, A.; Milcent, H.; Mirabelli, G.; Mohanty, G. B.; Monteleoni, B.; Muanza, G. S.; Muijs, A. J. M.; Musy, M.; Nagy, S.; Nahnhauer, R.; Naumov, V. A.; Natale, S.; Napolitano, M.; Nessi-Tedaldi, F.; Newman, H.; Nisati, A.; Novak, T.; Nowak, H.; Ofierzynski, R.; Organtini, G.; Pal, I.; Palomares, C.; Paolucci, P.; Paramatti, R.; Parriaud, J.-F.; Passaleva, G.; Patricelli, S.; Paul, T.; Pauluzzi, M.; Paus, C.; Pauss, F.; Pedace, M.; Pensotti, S.; Perret-Gallix, D.; Petersen, B.; Piccolo, D.; Pierella, F.; Pieri, M.; Pioppi, M.; Piroué, P. A.; Pistolesi, E.; Plyaskin, V.; Pohl, M.; Pojidaev, V.; Pothier, J.; Prokofiev, D.; Qing, C. R.; Rahal-Callot, G.; Rahaman, M. A.; Raics, P.; Raja, N.; Ramelli, R.; Rancoita, P. G.; Ranieri, R.; Raspereza, A.; Ravindran, K. C.; Razis, P.; Rembeczki, S.; Ren, D.; Rescigno, M.; Reucroft, S.; Rewiersma, P.; Riemann, S.; Riles, K.; Roe, B. P.; Rojkov, A.; Romero, L.; Rosca, A.; Rosier-Lees, S.; Roth, S.; Rubio, J. A.; Ruggiero, G.; Rykaczewski, H.; Saidi, R.; Sakharov, A.; Saremi, S.; Sarkar, S.; Salicio, J.; Sanchez, E.; Schäfer, C.; Schegelsky, V.; Schmitt, V.; Schoeneich, B.; Schopper, H.; Schotanus, D. J.; Sciacca, C.; Servoli, L.; Shen, C. Q.; Shevchenko, S.; Shivarov, N.; Shoutko, V.; Shumilov, E.; Shvorob, A.; Son, D.; Souga, C.; Spillantini, P.; Steuer, M.; Stickland, D. P.; Stoyanov, B.; Straessner, A.; Sudhakar, K.; Sulanke, H.; Sultanov, G.; Sun, L. Z.; Suter, H.; Swain, J. D.; Szillasi, Z.; Tang, X. W.; Tarjan, P.; Tauscher, L.; Taylor, L.; Tellili, B.; Teyssier, D.; Timmermans, C.; Ting, Samuel C. C.; Ting, S. M.; Tonwar, S. C.; Tóth, J.; Trowitzsch, G.; Tully, C.; Tung, K. L.; Ulbricht, J.; Unger, M.; Valente, E.

2008-09-01

406

Intramolecular photo-switching and intermolecular energy transfer as primary photoevents in photoreceptive processes: the case of Euglena gracilis.  

PubMed

In this paper we report the results of measurements performed by FLIM on the photoreceptor of Euglenagracilis. This organelle consists of optically bistable proteins, characterized by two thermally stable isomeric forms: A(498,) non fluorescent and B(462), fluorescent. Our data indicate that the primary photoevent of Euglena photoreception upon photon absorption consists of two contemporaneous different phenomena: an intramolecular photo-switch (i.e., A(498) becomes B(462)), and a intermolecular and unidirectional Forster-type energy transfer. During the FRET process, the fluorescent B(462) form acts as donor for the non-fluorescent A(498) form of the protein nearby, which acts as acceptor. We hypothesize that in nature these phenomena follow each other with a domino progression along the orderly organized and closely packed proteins in the photoreceptor layer(s), modulating the isomeric composition of the photoreceptive protein pool. This mechanism guarantees that few photons are sufficient to produce a signal detectable by the cell. PMID:19450554

Mercatelli, Raffaella; Quercioli, Franco; Barsanti, Laura; Evangelista, Valter; Coltelli, Primo; Passarelli, Vincenzo; Frassanito, Anna Maria; Gualtieri, Paolo

2009-07-24

407

Intramolecular photo-switching and intermolecular energy transfer as primary photoevents in photoreceptive processes: The case of Euglena gracilis  

SciTech Connect

In this paper we report the results of measurements performed by FLIM on the photoreceptor of Euglenagracilis. This organelle consists of optically bistable proteins, characterized by two thermally stable isomeric forms: A{sub 498,} non fluorescent and B{sub 462}, fluorescent. Our data indicate that the primary photoevent of Euglena photoreception upon photon absorption consists of two contemporaneous different phenomena: an intramolecular photo-switch (i.e., A{sub 498} becomes B{sub 462}), and a intermolecular and unidirectional Forster-type energy transfer. During the FRET process, the fluorescent B{sub 462} form acts as donor for the non-fluorescent A{sub 498} form of the protein nearby, which acts as acceptor. We hypothesize that in nature these phenomena follow each other with a domino progression along the orderly organized and closely packed proteins in the photoreceptor layer(s), modulating the isomeric composition of the photoreceptive protein pool. This mechanism guarantees that few photons are sufficient to produce a signal detectable by the cell.

Mercatelli, Raffaella; Quercioli, Franco [Istituto Sistemi Complessi, CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy)] [Istituto Sistemi Complessi, CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Italy); Barsanti, Laura; Evangelista, Valter [Istituto di Biofisica, CNR, Via Moruzzi 1, 56124 Pisa (Italy)] [Istituto di Biofisica, CNR, Via Moruzzi 1, 56124 Pisa (Italy); Coltelli, Primo [ISTI, CNR, Via Moruzzi 1, 56124 Pisa (Italy)] [ISTI, CNR, Via Moruzzi 1, 56124 Pisa (Italy); Passarelli, Vincenzo; Frassanito, Anna Maria [Istituto di Biofisica, CNR, Via Moruzzi 1, 56124 Pisa (Italy)] [Istituto di Biofisica, CNR, Via Moruzzi 1, 56124 Pisa (Italy); Gualtieri, Paolo, E-mail: paolo.gualtieri@pi.ibf.cnr.it [Istituto di Biofisica, CNR, Via Moruzzi 1, 56124 Pisa (Italy)] [Istituto di Biofisica, CNR, Via Moruzzi 1, 56124 Pisa (Italy)

2009-07-24

408

Study of the solar anisotropy of cosmic ray primaries of about 200 GeV energy with the L3+C muon detector  

Microsoft Academic Search

Context. Primary cosmic rays experience multiple deflections in the non-uniform galactic and heliospheric magnetic fields which may generate anisotropies. Aims. A study of anisotropies in the energy range between 100 and 500 GeV is performed. This energy range is not yet well explored. Methods. The L3 detector at the CERN electron-positron collider, LEP, is used for a study of the

P. Achard; O. Adriani; M. Aguilar-Benitez; M. van den Akker; J. Alcaraz; G. Alemanni; J. Allaby; A. Aloisio; M. G. Alviggi; H. Anderhub; V. P. Andreev; F. Anselmo; A. Arefiev; T. Azemoon; T. Aziz; P. Bagnaia; A. Bajo; G. Baksay; L. Baksay; J. Bahr; S. V. Baldew; S. Banerjee; A. Barczyk; R. Barillere; P. Bartalin; M. Basile; N. Batalova; R. Battiston; A. Bay; F. Becattini; U. Becker; F. Behner; L. Bellucci; R. Berbeco; J. Berdugo; P. Berges; B. Bertucci; B. L. Betev; M. Biasini; M. Biglietti; A. Biland; J. J. Blaising; S. C. Blyth; G. J. Bobbink; A. Boehm; L. Boldizsar; B. Borgia; S. Bottai; D. Bourilkov; M. Bourquin; S. Braccini; J. G. Branson; F. Brochu; J. D. Burger; W. J. Burger; X. D. Cai; M. Capell; G. C. Romeo; G. Carlino; A. Cartacci; J. Casaus; F. Cavallari; N. Cavallo; C. Cecchi; M. Cerrada; M. Chamizo; Y. H. Chang; M. Chemarin; A. Chen; G. Chen; H. F. Chen; H. S. Chen; T. Chiarusi; G. Chiefari; L. Cifarelli; F. Cindolo; I. Clare; R. Clare; G. Coignet; N. Colino; S. Costantini; B. de La Cruz; S. Cucciarelli; R. de Asmundis; P. Deglon; J. Debreczeni; A. Degre; K. Dehmelt; K. Deiters; D. della Volpe; E. Delmeire; P. Denes; F. DeNotaristefani; A. De Salvo; M. Diemoz; M. Dierckxsens; L. K. Ding; C. Dionisi; M. Dittmar; A. Doria; M. T. Dova; D. Duchesneau; M. Duda; I. Duran; B. Echenard; A. Eline; H. El Mamouni; A. Engler; F. J. Eppling; P. Extermann; G. Faber; M. A. Falagan; S. Falciano; A. Favara; J. Fay; O. Fedin; M. Felcini; T. Ferguson; E. Fiandrini; J. H. Field; F. Filthaut; W. Fisher; G. Forconi; K. Freudenreich; C. Furetta; Y. Galaktionov; S. N. Ganguli; P. Garcia-Abia; M. Gataullin; S. Gentile; S. Giagu; Z. F. Gong; H. J. Grabosch; G. Grenier; O. Grimm; H. Groenstege; M. W. Gruenewald; Y. N. Guo; S. Gupta; V. K. Gupta; A. Gurtu; L. J. Gutay; D. Haas; C. Haller; D. Hatzifotiadou; Y. Hayashi; Z. X. He; T. Hebbeker; A. Herve; H. Hofer; M. Hohlmann; G. Holzner; S. R. Hou; A. X. Huo; N. Ito; B. N. Jin; P. Jindal; C. L. Jing; L. W. Jones; P. de Jong; I. Josa-Mutuberria; V. Kantserov; M. Kaur; S. Kawakami; M. N. Kienzle-Focacci; J. K. Kim; J. Kirkby; W. Kittel; A. Klimentov; A. C. Konig; E. Kok; A. Korn; M. Kopal; V. Koutsenko; M. Kraber; H. H. Kuang; R. W. Kraemer; A. Kruger; J. Kuijpers; A. Kunin; P. L. de Guevara; I. Laktineh; G. Landi; M. Lebeau; A. Lebedev; P. Lebrun; P. Lecomte; P. Lecoq; P. Le Coultre; J. M. Le Goff; Y. Lei; H. Leich; R. Leiste; M. Levtchenko; P. Levtchenko; C. Li; L. Li; Z. C. Li; S. Likhoded; C. H. Lin; W. T. Lin; F. L. Linde; L. Lista; Z. A. Liu; W. Lohmann; E. Longo; Y. S. Lu; C. Luci; L. Luminari; W. Lustermann; W. G. Ma; X. H. Ma; Y. Q. Ma; L. Malgeri; A. Malinin; C. Mana; J. Mans; J. P. Martin; F. Marzano; K. Mazumdar; R. R. McNeil; S. Mele; X. W. Meng; L. Merola; M. Meschini; W. J. Metzger; A. Mihul; A. van Mil; H. Milcent; G. Mirabelli; G. B. Mohanty; B. Monteleoni; G. S. Muanza; A. J. M. Muijs; M. Musy; S. Nagy; R. Nahnhauer; V. A. Naumov; S. Natale; M. Napolitano; F. Nessi-Tedaldi; H. Newman; A. Nisati; T. Novak; H. Nowak; R. Ofierzynski; G. Organtini; I. Pal; C. Palomares; P. Paolucci; R. Paramatti; J. F. Parriaud; G. Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; F. Pauss; M. Pedace; S. Pensotti; D. Perret-Gallix; B. Petersen; D. Piccolo; F. Pierella; M. Pieri; M. Pioppi; P. A. Piroue; E. Pistolesi; V. Plyaskin; M. Pohl; V. Pojidaev; J. Pothier; D. Prokofiev; C. R. Qing; G. Rahal-Callot; M. A. Rahaman; P. Raics; N. Raja; R. Ramelli; P. G. Rancoita; R. Ranieri; A. Raspereza; K. C. Ravindran; P. Razis; S. Rembeczki; D. Ren; M. Rescigno; S. Reucroft; P. Rewiersma; S. Riemann; K. Riles; B. P. Roe; A. Rojkov; L. Romero; A. Rosca; S. Rosier-Lees; S. Roth; J. A. Rubio; G. Ruggiero; H. Rykaczewski; R. Saidi; A. Sakharov; S. Saremi; S. Sarkar; J. Salicio; E. Sanchez; C. Schafer; V. Schegelsky; V. Schmitt; B. Schoeneich; H. Schopper; D. J. Schotanus; C. Sciacca; L. Servoli; C. Q. Shen; S. Shevchenko; N. Shivarov; V. Shoutko; E. Shumilov; A. Shvorob; D. Son; C. Souga; P. Spillantini; M. Steuer; D. P. Stickland; B. Stoyanov; A. Straessner; K. Sudhakar; H. Sulanke; G. Sultanov; L. Z. Sun; H. Suter; J. D. Swain; Z. Szillasi; X. W. Tang; P. Tarjan; L. Tauscher; L. Taylor; B. Tellili; D. Teyssier; C. Timmermans; C. C. Ting; S. M. Ting; S. C. Tonwar; J. Toth; G. Trowitzsch; C. Tully; K. L. Tung; J. Ulbricht; M. Unger; E. Valente; H. Verkooijen; R. T. V. de Walle; R. Vasquez; G. Vesztergombi; I. Vetlitsky; G. Viertel; M. Vivargent; S. Vlachos; I. Vodopianov; H. Vogel; H. Vogt; I. Vorobiev; A. A. Vorobyov; M. Wadhwa; R. G. Wang; Q. Wang; X. L. Wang; X. W. Wang; Z. M. Wang; M. Weber; R. van Wijk; T. A. M. Wijnen; H. Wilkens; S. Wynhoff; L. Xia; Y. P. Xu; J. S. Xu; Z. Z. Xu; J. Yamamoto; B. Z. Yang; C. G. Yang; H. J. Yang; M. Yang; X. F. Yang; Z. G. Yao; S. C. Yeh; Z. Q. Yu; A. Zalite; Y. Zalite; C. Zhang; F. Zhang; J. Zhang; S. Zhang; Z. P. Zhang; J. Zhao

2008-01-01

409

Study of the solar anisotropy of cosmic ray primaries of about 200 GeV energy with the L3+C muon detector  

Microsoft Academic Search

Context: Primary cosmic rays experience multiple deflections in the non-uniform galactic and heliospheric magnetic fields which may generate anisotropies. Aims: A study of anisotropies in the energy range between 100 and 500 GeV is performed. This energy range is not yet well explored. Methods: The L3 detector at the CERN electron-positron collider, LEP, is used for a study of the

P. Achard; O. Adriani; M. Aguilar-Benitez; M. van den Akker; J. Alcaraz; G. Alemanni; J. Allaby; A. Aloisio; M. G. Alviggi; H. Anderhub; V. P. Andreev; F. Anselmo; A. Arefiev; T. Azemoon; T. Aziz; P. Bagnaia; A. Bajo; G. Baksay; L. Baksay; J. Bähr; S. V. Baldew; S. Banerjee; A. Barczyk; R. Barillère; P. Bartalini; M. Basile; N. Batalova; R. Battiston; A. Bay; F. Becattini; U. Becker; F. Behner; L. Bellucci; R. Berbeco; J. Berdugo; P. Berges; B. Bertucci; B. L. Betev; M. Biasini; M. Biglietti; A. Biland; J. J. Blaising; S. C. Blyth; G. J. Bobbink; A. Böhm; L. Boldizsar; B. Borgia; S. Bottai; D. Bourilkov; M. Bourquin; S. Braccini; J. G. Branson; F. Brochu; J. D. Burger; W. J. Burger; X. D. Cai; M. Capell; G. Cara Romeo; G. Carlino; A. Cartacci; J. Casaus; F. Cavallari; N. Cavallo; C. Cecchi; M. Cerrada; M. Chamizo; Y. H. Chang; M. Chemarin; A. Chen; G. Chen; H. F. Chen; H. S. Chen; T. Chiarusi; G. Chiefari; L. Cifarelli; F. Cindolo; I. Clare; R. Clare; G. Coignet; N. Colino; S. Costantini; B. de la Cruz; S. Cucciarelli; R. de Asmundis; P. Déglon; J. Debreczeni; A. Degré; K. Dehmelt; K. Deiters; D. della Volpe; E. Delmeire; P. Denes; F. DeNotaristefani; A. De Salvo; M. Diemoz; M. Dierckxsens; L. K. Ding; C. Dionisi; M. Dittmar; A. Doria; M. T. Dova; D. Duchesneau; M. Duda; I. Duran; B. Echenard; A. Eline; H. El Mamouni; A. Engler; F. J. Eppling; P. Extermann; G. Faber; M. A. Falagan; S. Falciano; A. Favara; J. Fay; O. Fedin; M. Felcini; T. Ferguson; E. Fiandrini; J. H. Field; F. Filthaut; W. Fisher; G. Forconi; K. Freudenreich; C. Furetta; Yu. Galaktionov; S. N. Ganguli; P. Garcia-Abia; M. Gataullin; S. Gentile; S. Giagu; Z. F. Gong; H. J. Grabosch; G. Grenier; O. Grimm; H. Groenstege; M. W. Gruenewald; Y. N. Guo; S. Gupta; V. K. Gupta; A. Gurtu; L. J. Gutay; D. Haas; Ch. Haller; D. Hatzifotiadou; Y. Hayashi; Z. X. He; T. Hebbeker; A. Hervé; J. Hirschfelder; H. Hofer; H. Hoferjun; M. Hohlmann; G. Holzner; S. R. Hou; A. X. Huo; N. Ito; B. N. Jin; P. Jindal; C. L. Jing; L. W. Jones; P. de Jong; I. Josa-Mutuberría; V. Kantserov; M. Kaur; S. Kawakami; M. N. Kienzle-Focacci; J. K. Kim; J. Kirkby; W. Kittel; A. Klimentov; A. C. König; E. Kok; A. Korn; M. Kopal; V. Koutsenko; M. Kräber; H. H. Kuang; R. W. Kraemer; A. Krüger; J. Kuijpers; A. Kunin; P. Ladron de Guevara; I. Laktineh; G. Landi; M. Lebeau; A. Lebedev; P. Lebrun; P. Lecomte; P. Lecoq; P. Le Coultre; J. M. Le Goff; Y. Lei; H. Leich; R. Leiste; M. Levtchenko; P. Levtchenko; C. Li; L. Li; Z. C. Li; S. Likhoded; C. H. Lin; W. T. Lin; F. L. Linde; L. Lista; Z. A. Liu; W. Lohmann; E. Longo; Y. S. Lu; C. Luci; L. Luminari; W. Lustermann; W. G. Ma; X. H. Ma; Y. Q. Ma; L. Malgeri; A. Malinin; C. Maña; J. Mans; J. P. Martin; F. Marzano; K. Mazumdar; R. R. McNeil; S. Mele; X. W. Meng; L. Merola; M. Meschini; W. J. Metzger; A. Mihul; A. van Mil; H. Milcent; G. Mirabelli; G. B. Mohanty; B. Monteleoni; G. S. Muanza; A. J. M. Muijs; M. Musy; S. Nagy; R. Nahnhauer; V. A. Naumov; S. Natale; M. Napolitano; F. Nessi-Tedaldi; H. Newman; A. Nisati; T. Novak; H. Nowak; R. Ofierzynski; G. Organtini; I. Pal; C. Palomares; P. Paolucci; R. Paramatti; J.-F. Parriaud; G. Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; F. Pauss; M. Pedace; S. Pensotti; D. Perret-Gallix; B. Petersen; D. Piccolo; F. Pierella; M. Pieri; M. Pioppi; P. A. Piroué; E. Pistolesi; V. Plyaskin; M. Pohl; V. Pojidaev; J. Pothier; D. Prokofiev; C. R. Qing; G. Rahal-Callot; M. A. Rahaman; P. Raics; N. Raja; R. Ramelli; P. G. Rancoita; R. Ranieri; A. Raspereza; K. C. Ravindran; P. Razis; S. Rembeczki; D. Ren; M. Rescigno; S. Reucroft; P. Rewiersma; S. Riemann; K. Riles; B. P. Roe; A. Rojkov; L. Romero; A. Rosca; S. Rosier-Lees; S. Roth; J. A. Rubio; G. Ruggiero; H. Rykaczewski; R. Saidi; A. Sakharov; S. Saremi; S. Sarkar; J. Salicio; E. Sanchez; C. Schäfer; V. Schegelsky; V. Schmitt; B. Schoeneich; H. Schopper; D. J. Schotanus; C. Sciacca; L. Servoli; C. Q. Shen; S. Shevchenko; N. Shivarov; V. Shoutko; E. Shumilov; A. Shvorob; D. Son; C. Souga; P. Spillantini; M. Steuer; D. P. Stickland; B. Stoyanov; A. Straessner; K. Sudhakar; H. Sulanke; G. Sultanov; L. Z. Sun; H. Suter; J. D. Swain; Z. Szillasi; X. W. Tang; P. Tarjan; L. Tauscher; L. Taylor; B. Tellili; D. Teyssier; C. Timmermans; Samuel C. C. Ting; S. M. Ting; S. C. Tonwar; J. Tóth; G. Trowitzsch; C. Tully; K. L. Tung; J. Ulbricht; M. Unger; E. Valente; H. Verkooijen; R. T. Van de Walle; R. Vasquez; G. Vesztergombi; I. Vetlitsky; G. Viertel; M. Vivargent; S. Vlachos; I. Vodopianov; H. Vogel; H. Vogt; I. Vorobiev; A. A. Vorobyov; M. Wadhwa; R. G. Wang; Q. Wang; X. L. Wang; X. W. Wang; Z. M. Wang; M. Weber; R. van Wijk; T. A. M. Wijnen; H. Wilkens; S. Wynhoff; L. Xia; Y. P. Xu; J. S. Xu; Z. Z. Xu; J. Yamamoto; B. Z. Yang; C. G. Yang; H. J. Yang; M. Yang; X. F. Yang; Z. G. Yao; S. C. Yeh; Z. Q. Yu; An. Zalite; Yu. Zalite

2008-01-01

410

Life cycle Analysis of Aluminum Foil Packaging Material.  

PubMed

A fundamental tent of life cycle analysis (LCA) is that every material product must become a waste. To choose the greener products, it is necessary to take into account their environmental impacts from cradle to grave. LCA is the tool used to measure environmental improvements. Aluminum (Al) is the third most common element found in the earth's crust, after oxygen and silicon. Al packaging foil was chosen as the material for the study with its life cycle perspective at Alexandria. The Al packaging produced from virgin and recycled Al was investigated through life cycle stages in these two production processes; primary and secondary. The aim of this study is to evaluate the environmental impact of aluminum packaging process by using life cycle analysis of its product from two different starting raw materials (virgin and recycled aluminum). The input and output materials, energy, water, natural gas consumptions, and solid waste uses in the foil industry had been analyzed in order to identify those with significant contribution to the total environmental impacts. From the survey done on the two life cycles, it was found that in environmental terms, the most important emissions from the primary process are the emission of CO(2) and perfluorocarbon (PFC) gases, which produce the greenhouse effect, and SO(2) as well as the emission of fluorides and polyaromatic hydrocarbons (PAH compounds), which are toxic to humans and the environment. On over all material balance, it was found that the ingot shares by 45% of the feed to the casthouse furnaces at Egyptian Copper Work (ECW), net production of the casthouse is 43.76% and the yield of rotary dross furnace (RDF) is 28.8%. The net production of the foil unit represents 35% of the total input to the unit. By comparing the two life cycles, it is obvious that, for water consumption, 93.5% is used in the primary cycle, while 6.5% is used in the secondary cycle. For electricity consumption, 99.3% is used in the primary cycle; while 0.63% is used in the secondary cycle. For the natural gas consumption, 46.66% is used in the primary cycle excluding Nag' Hammady as it uses fuel oil, while 53.34% is used in the secondary cycle. Using a matrix approach, the primary cycle scored 6 heavy loaded factors out of 9, while the secondary cycle scored 3 heavy loaded factors out of 9. It can be concluded that Al recycling (secondary cycle) in Al industry decreases the use of virgin material, energy use, and environmental loadings, while increasing the economic life of products, and reducing overall material demands. So, the secondary cycle is to be recommended and is the most favorable option in most of the factors influencing the two cycles. Monitoring of the furnaces, automatic control of the metal, proper dross cooling, better refining of molten Al, rate of solidification of molten Al, and proper annealing process will lead to reduction of the overall fuel, water, and electricity consumption and metal losses will be minimum. PMID:17382061

El Sebaie, Olfat; Ahmed, Manal; Hussein, Ahmed; El Sharkawy, Fahmay; Samy, Manal

2006-01-01

411

Assessment of external combustion, Brayton-cycle engine potential in total and integrated energy systems  

SciTech Connect

The history, advantages, disadvantages, and performance and cost characteristics of the external-combustion, Brayton engine are discussed. Included are studies of external combustion, Brayton engines in Integrated Energy Systems, and comparisons with current technologies, such as diesels and gas turbines, as well as with other advanced prime-mover technologies, such as large Stirling engines and adiabatic turbocompound diesel engines. Lastly, a development program, one that would lead to a commercializable external combustion, Brayton engine using an atmospheric fluidized bed combustor is described. The fluidized bed offers a method for burning coal in an environmentally acceptable manner at a fairly reasonable cost so that the external combustion Brayton concept can be used in the residential/commercial sector. Based on this study, it appears that the external combustion, Brayton engine, using a fluidized-bed combustion system, offers a technologically sound alternative for developing an economically viable, environmentally acceptable method for using non-scarce fuels. Although the efficiency of the engine is not as high as that projected for large diesel and Stirling engines, the capital cost advantages, fuel flexibility, relatively low developmental costs, and high chance of success make it an attractive alternative.

Marciniak, T.J.; Bratis, J.C.; Davis, A.; Jain, M.L.; Ashe, T.L.; Six, L.D.; Trimble, S.W.

1980-03-01

412

Economic evaluation of the Annual Cycle Energy System (ACES). Volume II. Detailed results. Final report  

SciTech Connect

The energy effectiveness and the economic viability of the ACES concept are examined. ACES is studied in a variety of different applications and compared to a number of conventional systems. The different applications are studied in two groups: the class of building into which the ACES is incorporated and the climatic region in which the ACES is located. Buildings investigated include single-family and multi-family residences and a commercial office building. The application of ACES to each of these building types is studied in Minneapolis, Atlanta, and Philadelphia. The economic evaluation of the ACES is based on a comparison of the present worth of the ACES to the present worth of conventional systems; namely, electric resistance heating, electric air conditioning, and electric domestic water heating; air-to-air heat pump and electric domestic water heating; oil-fired furnace, electric air conditioning, and electric domestic water heating; and gas-fired furnace, electric air conditioning, and gas domestic water heating.

Not Available

1980-05-01

413

Environmental Life-cycle Assessment of Passenger Transportation An Energy, Greenhouse Gas, and Criteria Pollutant Inventory of Rail and Air Transportation  

Microsoft Academic Search

The passenger transportation modes of rail and air are critical systems relied upon for business and leisure. When considering their environmental effects, most studies and policy focus on the fuel use of the vehicles, and ignore the energy and other resource inputs and environmental outputs from the life cycles of other components. Vehicle manufacturing and maintenance, infrastructure construction and operation,

Arpad Horvath; Mikhail Chester

2008-01-01

414

Environmental Life-cycle Assessment of Passenger Transportation: A Detailed Methodology for Energy, Greenhouse Gas and Criteria Pollutant Inventories of Automobiles, Buses, Light Rail, Heavy Rail and Air  

Microsoft Academic Search

The passenger transportation modes of auto, bus, heavy rail, light rail and air are critical systems relied upon for business and leisure. When considering their environmental effects, most studies and policy focus on the fuel use of the vehicles, and ignore the energy and other resource inputs and environmental outputs from the life cycles of necessary infrastructures, fuels, and vehicles.

Mikhail Chester; Arpad Horvath

2007-01-01

415

CCA-Treated wood disposed in landfills and life-cycle trade-offs with waste-to-energy and MSW landfill disposal  

E-print Network

CCA-Treated wood disposed in landfills and life-cycle trade-offs with waste-to-energy and MSW February 2007 Available online 9 April 2007 Abstract Chromated copper arsenate (CCA)-treated wood is a preservative treated wood construction product that grew in use in the 1970s for both residential

Florida, University of

416

Omics in the Arctic: Genome-enabled Contributions to Carbon Cycle Research in High-Latitude Ecosystems (JGI Seventh Annual User Meeting 2012: Genomics of Energy and Environment)  

ScienceCinema

Stan Wullschleger of Oak Ridge National Laboratory on "Omics in the Arctic: Genome-enabled Contributions to Carbon Cycle Research in High-Latitude Ecosystems" on March 22, 2012 at the 7th Annual Genomics of Energy & Environment Meeting in Walnut Creek, California.

Wullschleger, Stan [ORNL

2013-01-22

417

Life cycle assessment and energy pay-back time of advanced photovoltaic modules: CdTe and CIS compared to poly-Si  

Microsoft Academic Search

The paper is concerned with the results of a thorough energy and life cycle assessment (LIA) of CdTe and CIS photovoltaic modules. The analysis is based on actual production data, making it one of the very first of its kind to be presented to the scientific community, and therefore especially worthy of attention as a preliminary indication of the future

Marco Raugei; Silvia Bargigli; Sergio Ulgiati

2007-01-01

418

Net energy, CO 2 emission, and life-cycle cost assessment of cassava-based ethanol as an alternative automotive fuel in China  

Microsoft Academic Search

Assessment on net energy, external cost of carbon dioxide (CO2) emissions and cost of using cassava-based ethanol as an alternative automotive fuel has been conducted based on its holistic life-cycle, from feedstock production (source) to fuel combustion. And, a new indicator, figure of merit (FM), is proposed for grading conventional gasoline (CG) and cassava-based ethanol (CE): it links net energy

Zhiyuan Hu; Fang Fang; DaoFeng Ben; Gengqiang Pu; Chengtao Wang

2004-01-01

419

Seasonal cycle and long-term trend of solar energy fluxes through Arctic sea ice  

NASA Astrophysics Data System (ADS)

Arctic sea ice has not only decreased in volume during the last decades, but has also changed in its physical properties towards a thinner and more seasonal ice cover. These changes strongly impact the energy budget, and might affect the ice-associated ecosystems. In this study, we quantify solar shortwave fluxes through sea ice for the entire Arctic during all seasons. To focus on sea-ice-related processes, we exclude fluxes through open water, scaling linearly with sea ice concentration. We present a new parameterization of light transmittance through sea ice for all seasons as a function of variable sea ice properties. The maximum monthly mean solar heat flux under the ice of 30 × 105 Jm-2 occurs in June, enough heat to melt 0.3 m of sea ice. Furthermore, our results suggest that 96% of the annual solar heat input through sea ice occurs during only a 4-month period from May to August. Applying the new parameterization to remote sensing and reanalysis data from 1979 to 2011, we find an increase in transmitted light of 1.5% yr-1 for all regions. This corresponds to an increase in potential sea ice bottom melt of 63% over the 33-year study period. Sensitivity studies reveal that the results depend strongly on the timing of melt onset and the correct classification of ice types. Assuming 2 weeks earlier melt onset, the annual transmitted solar radiation to the upper ocean increases by 20%. Continuing the observed transition from a mixed multi-year/first-year sea ice cover to a seasonal ice cover results in an increase in light transmittance by an additional 18%.

Arndt, S.; Nicolaus, M.

2014-11-01

420

Introduction to combined cycles  

NASA Astrophysics Data System (ADS)

Ideas and concepts underlying the technology of combined cycles including the scientific principles involved and the reasons these cycles are in fashion at the present time, are presented. A cycle is a steady flow process for conversion of heat energy into work, in which a working medium passes through a range of states, returning to its original state. Cycles for power production are the steam cycle, which is a closed cycle, and the gas turbine, which represents an open cycle. Combined cycle thermodynamic parameters, are discussed. The general arrangement of the plant is outlined and important features of their component parts described. The scope for future development is discussed. It is concluded that for the next few years the natural gas fired combined cycle will be the main type of plant installed for electricity generation and cogeneration. Whilst gas turbines may not increase substantially in unit size, there remains scope for further increase in firing temperature with consequent increase in cycle performance. However the larger global reserves of coal are providing an incentive to the development of plant for clean coal combustion using the inherent advantage of the combined cycle to attain high efficiencies.

Moore, M. J.

421

Exploring the Water Cycle  

NSDL National Science Digital Library

In this lesson, students will learn about the water cycle and how energy from the sun and the force of gravity drive this cycle. The emphasis in this lesson will be on having students understand the processes that take place in moving water through Earthâs system.

422

Facies analysis of an Upper Cretaceous high-energy rudist-dominated carbonate ramp (Matese Mountains, central-southern Italy): subtidal and peritidal cycles  

NASA Astrophysics Data System (ADS)

Upper Cretaceous shallow-water limestones rich in rudists have been studied in the Matese Mountains. They show a preponderance of skeletal components (molluscs and benthic foraminifers) and a lack of non-skeletal grains. The most prominent sediments of the studied stratigraphic interval are rudist-dominated fine- to coarse-grained lithologies. Most of the Senonian successions are characterized by massive neritic limestones rich in molluscs (mostly rudists and subordinate gastropods) and a few corals. The sediments were generated in situ on shelves where rudist bivalves were the primary sediment producers. These sediments were actively moved by storms, waves and swells. The finer fractions were probably winnowed out and deposited in deeper water. Well-bedded dolomitized mudstones/wackestones, microbial laminites and benthic foraminifer wackestones characterize some successions where they rhythmically alternate and testify to deposition in tidal-flat environments. The lithofacies, faunal and taphonomic characters and the sedimentary structures are typical of a ramp-like open shelf with local peritidal deposition. The vertical lithofacies organization consists of numerous decimetre- to metre-scale shallowing-upward subtidal and peritidal cycles. A complete transition from peritidal to subtidal cycles has been recognized and documented. The peritidal cycles are usually bounded by desiccation surfaces and/or dolomitized crusts followed by shallow-subtidal to peritidal facies of the next cycle. The subtidal cycles are typified by rudist floatstones passing to large-scale cross-bedded bioclastic packstones/grainstones. Current and storm structures are distinctive features; in shallower-water environments the effects of submarine erosion prevail; hardgrounds commonly developed and the resulting cycles are usually truncated. The formation of the peritidal cycles appears to have been controlled by accommodation space in response to fluctuations in relative sea level. The formation of the subtidal cycles was determined by sedimentation rates in response to fluctuations in the zones of fair-weather and storm-wave reworking, in turn controlled by relative sea level. This indicates that sediment production and supply were important controlling factors in the cycle formation during the early Senonian stratigraphic interval. The recognition of similar depositional styles in other early Senonian successions cropping out in the southern Apennines suggests that this type of sedimentation is a recurring attribute of the Upper Cretaceous open shelves.

Ruberti, Daniela

1997-10-01

423
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