Meeting global policy commitments carbon sequestration and southern pine forests

Treesearch

Kurt H. Johnsen; David N. Wear; R. Oren; R.O. Teskey; Felipe Sanchez; Rodney E. Will; John Butnor; D. Markewitz; D. Richter; T. Rials; H.L. Allen; J. Seiler; D. Ellsworth; Christopher Maier; G. Katul; P.M. Dougherty

2001-01-01

In managed forests, the amount of carbon further sequestered will be determined by (1) the increased amount of carbon in standing biomass (resulting from land-use changes and increased productivity); (2) the amount of recalcitrant carbon remaining below ground at the end of rotations; and (3) the amount of carbon sequestered in products created from harvested wood....

A comparative assessment of the financial costs and carbon benefits of REDD+ strategies in Southeast Asia

NASA Astrophysics Data System (ADS)

Graham, Victoria; Laurance, Susan G.; Grech, Alana; McGregor, Andrew; Venter, Oscar

2016-11-01

REDD+ holds potential for mitigating emissions from tropical forest loss by providing financial incentives for carbon stored in forests, but its economic viability is under scrutiny. The primary narrative raised in the literature is that REDD+ will be of limited utility for reducing forest carbon loss in Southeast Asia, while the level of finance committed falls short of profits from alternative land-use activities in the region, including large-scale timber and oil palm operations. Here we assess the financial costs and carbon benefits of various REDD+ strategies deployed in the region. We find the cost of reducing emissions ranges from 9 to 75 per tonne of avoided carbon emissions. The strategies focused on reducing forest degradation and promoting forest regrowth are the most cost-effective ways of reducing emissions and used in over 60% of REDD+ projects. By comparing the financial costs and carbon benefits of a broader range of strategies than previously assessed, we highlight the variation between different strategies and draw attention to opportunities where REDD+ can achieve maximum carbon benefits cost-effectively. These findings have broad policy implications for Southeast Asia. Until carbon finance escalates, emissions reductions can be maximized from reforestation, reduced-impact logging and investing in improved management of protected areas. Targeting cost-efficient opportunities for REDD+ is important to improve the efficiency of national REDD+ policy, which in-turn fosters greater financial and political support for the scheme.

40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

Code of Federal Regulations, 2010 CFR

2010-07-01

... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons...

40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

Code of Federal Regulations, 2014 CFR

2014-07-01

... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons...

40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

Code of Federal Regulations, 2011 CFR

2011-07-01

... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons...

40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

Code of Federal Regulations, 2012 CFR

2012-07-01

... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons...

40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

Code of Federal Regulations, 2013 CFR

2013-07-01

... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons...

The impact of middle manager affective commitment on perceived improvement program implementation success.

PubMed

Fryer, Ashley-Kay; Tucker, Anita L; Singer, Sara J

Recent literature suggests that middle manager affective commitment (emotional attachment, identification, and involvement) to an improvement program may influence implementation success. However, less is known about the interplay between middle manager affective commitment and frontline worker commitment, another important driver of implementation success. We contribute to this research by surveying middle managers who directly manage frontline workers on nursing units. We assess how middle manager affective commitment is related to their perceptions of implementation success and whether their perceptions of frontline worker support mediate this relationship. We also test whether a set of organizational support factors foster middle manager affective commitment. We adapt survey measures of manager affective commitment to our research context of hospitals. We surveyed 67 nurse managers from 19 U.S. hospitals. We use hierarchical linear regression to assess relationships among middle manager affective commitment to their units' falls reduction program and their perceptions of three constructs related to the program: frontline worker support, organizational support, and implementation success. Middle manager affective commitment to their unit's falls reduction program is positively associated with their perception of implementation success. This relationship is mediated by their perception of frontline worker support for the falls program. Moreover, middle managers' affective commitment to their unit's falls program mediates the relationship between perceived organizational support for the program and perceived implementation success. We, through this research, offer an important contribution by providing empirical support of factors that may influence successful implementation of an improvement program: middle manager affective commitment, frontline worker support, and organizational support for an improvement program. Increasing levels of middle manager affective commitment to an improvement program could strengthen program implementation success by facilitating frontline worker support for the program. Furthermore, providing the organizational support items in our survey construct may bolster middle manager affective commitment.

Committed emissions from existing and planned power plants and asset stranding required to meet the Paris Agreement

NASA Astrophysics Data System (ADS)

Pfeiffer, Alexander; Hepburn, Cameron; Vogt-Schilb, Adrien; Caldecott, Ben

2018-05-01

Over the coming decade, the power sector is expected to invest ~7.2 trillion USD in power plants and grids globally, much of it into CO2-emitting coal and gas plants. These assets typically have long lifetimes and commit large amounts of (future) CO2 emissions. Here, we analyze the historic development of emission commitments from power plants and compare the emissions committed by current and planned plants with remaining carbon budgets. Based on this comparison we derive the likely amount of stranded assets that would be required to meet the 1.5 °C–2 °C global warming goal. We find that even though the growth of emission commitments has slowed down in recent years, currently operating generators still commit us to emissions (~300 GtCO2) above the levels compatible with the average 1.5 °C–2 °C scenario (~240 GtCO2). Furthermore, the current pipeline of power plants would add almost the same amount of additional commitments (~270 GtCO2). Even if the entire pipeline was cancelled, therefore, ~20% of global capacity would need to be stranded to meet the climate goals set out in the Paris Agreement. Our results can help companies and investors re-assess their investments in fossil-fuel power plants, and policymakers strengthen their policies to avoid further carbon lock-in.

Committed climate change due to historical land use and management: the concept

NASA Astrophysics Data System (ADS)

Freibauer, Annette; Dolman, Han; Don, Axel; Poeplau, Christopher

2013-04-01

A significant fraction of the European land surface has changed its land use over the last 50 years. Management practices have changed in the same period in most land use systems. These changes have affected the carbon and greenhouse gas (GHG) balance of the European land surface. Land use intensity, defined here loosely as the degree to which humans interfere with the land, strongly affects GHG emissions. Land use and land management changes suggest that the variability of the carbon balance and of GHG emissions of cultivated land areas in Europe is much more driven by land use history and management than driven by climate. Importantly changes in land use and its management have implications for future GHG emissions, and therefore present a committed climate change, defined as inevitable future additional climate change induced by past human activity. It is one of the key goals of the large-scale integrating research project "GHG-Europe - Greenhouse gas management in European land use systems" to quantify the committed climate change due to legacy effects by land use and management. The project is funded by the European Commission in the 7th framework programme (Grant agreement no.: 244122). This poster will present the conceptual approach taken to reach this goal. (1) First of all we need to proof that at site, or regional level the management effects are larger than climate effects on carbon balance and GHG emissions. Observations from managed sites and regions will serve as empirical basis. Attribution experiments with models based on process understanding are run on managed sites and regions will serve to demonstrate that the observed patterns of the carbon balance and GHG emissions can only be reproduced when land use and management are included as drivers. (2) The legacy of land use changes will be quantified by combining spatially explicit time series of land use changes with response functions of carbon pools. This will allow to separate short-term and long-term effects of land-use changes, to quantify how much current changes in biomass and soil carbon are driven by past land use change and how much future changes in biomass and soil carbon have already been committed by past and present land use changes. (3) The legacy of land management changes will be quantified by combining spatially explicit time series of land management activities with response functions and relatively simple models of carbon pools and greenhouse gases. This will allow to detect major trends and spatial patterns in carbon and GHG fluxes driven by intensification or extensification over the last decades. The poster will concentrate on background, concept of the legacy analysis, data sources and the scientific strategy for deriving the climate change committed by past and present land use and management in Europe.

Positive Feedback of NDT80 Expression Ensures Irreversible Meiotic Commitment in Budding Yeast

PubMed Central

Tsuchiya, Dai; Yang, Yang; Lacefield, Soni

2014-01-01

In budding yeast, meiotic commitment is the irreversible continuation of the developmental path of meiosis. After reaching meiotic commitment, cells finish meiosis and gametogenesis, even in the absence of the meiosis-inducing signal. In contrast, if the meiosis-inducing signal is removed and the mitosis-inducing signal is provided prior to reaching meiotic commitment, cells exit meiosis and return to mitosis. Previous work has shown that cells commit to meiosis after prophase I but before entering the meiotic divisions. Since the Ndt80 transcription factor induces expression of middle meiosis genes necessary for the meiotic divisions, we examined the role of the NDT80 transcriptional network in meiotic commitment. Using a microfluidic approach to analyze single cells, we found that cells commit to meiosis in prometaphase I, after the induction of the Ndt80-dependent genes. Our results showed that high-level expression of NDT80 is important for the timing and irreversibility of meiotic commitment. A modest reduction in NDT80 levels delayed meiotic commitment based on meiotic stages, although the timing of each meiotic stage was similar to that of wildtype cells. A further reduction of NDT80 resulted in the surprising finding of inappropriately uncommitted cells: withdrawal of the meiosis-inducing signal and addition of the mitosis-inducing signal to cells at stages beyond metaphase I caused return to mitosis, leading to multi-nucleate cells. Since Ndt80 enhances its own transcription through positive feedback, we tested whether positive feedback ensured the irreversibility of meiotic commitment. Ablating positive feedback in NDT80 expression resulted in a complete loss of meiotic commitment. These findings suggest that irreversibility of meiotic commitment is a consequence of the NDT80 transcriptional positive feedback loop, which provides the high-level of Ndt80 required for the developmental switch of meiotic commitment. These results also illustrate the importance of irreversible meiotic commitment for maintaining genome integrity by preventing formation of multi-nucleate cells. PMID:24901499

Carbon-climate feedbacks accelerate ocean acidification

NASA Astrophysics Data System (ADS)

Matear, Richard J.; Lenton, Andrew

2018-03-01

Carbon-climate feedbacks have the potential to significantly impact the future climate by altering atmospheric CO2 concentrations (Zaehle et al. 2010). By modifying the future atmospheric CO2 concentrations, the carbon-climate feedbacks will also influence the future ocean acidification trajectory. Here, we use the CO2 emissions scenarios from four representative concentration pathways (RCPs) with an Earth system model to project the future trajectories of ocean acidification with the inclusion of carbon-climate feedbacks. We show that simulated carbon-climate feedbacks can significantly impact the onset of undersaturated aragonite conditions in the Southern and Arctic oceans, the suitable habitat for tropical coral and the deepwater saturation states. Under the high-emissions scenarios (RCP8.5 and RCP6), the carbon-climate feedbacks advance the onset of surface water under saturation and the decline in suitable coral reef habitat by a decade or more. The impacts of the carbon-climate feedbacks are most significant for the medium- (RCP4.5) and low-emissions (RCP2.6) scenarios. For the RCP4.5 scenario, by 2100 the carbon-climate feedbacks nearly double the area of surface water undersaturated with respect to aragonite and reduce by 50 % the surface water suitable for coral reefs. For the RCP2.6 scenario, by 2100 the carbon-climate feedbacks reduce the area suitable for coral reefs by 40 % and increase the area of undersaturated surface water by 20 %. The sensitivity of ocean acidification to the carbon-climate feedbacks in the low to medium emission scenarios is important because recent CO2 emission reduction commitments are trying to transition emissions to such a scenario. Our study highlights the need to better characterise the carbon-climate feedbacks and ensure we do not underestimate the projected ocean acidification.

Atmospheric CO2 mole fraction affects stand-scale carbon use efficiency of sunflower by stimulating respiration in light.

PubMed

Gong, Xiao Ying; Schäufele, Rudi; Lehmeier, Christoph Andreas; Tcherkez, Guillaume; Schnyder, Hans

2017-03-01

Plant carbon-use-efficiency (CUE), a key parameter in carbon cycle and plant growth models, quantifies the fraction of fixed carbon that is converted into net primary production rather than respired. CUE has not been directly measured, partly because of the difficulty of measuring respiration in light. Here, we explore if CUE is affected by atmospheric CO 2 . Sunflower stands were grown at low (200 μmol mol -1 ) or high CO 2 (1000 μmol mol -1 ) in controlled environment mesocosms. CUE of stands was measured by dynamic stand-scale 13 C labelling and partitioning of photosynthesis and respiration. At the same plant age, growth at high CO 2 (compared with low CO 2 ) led to 91% higher rates of apparent photosynthesis, 97% higher respiration in the dark, yet 143% higher respiration in light. Thus, CUE was significantly lower at high (0.65) than at low CO 2 (0.71). Compartmental analysis of isotopic tracer kinetics demonstrated a greater commitment of carbon reserves in stand-scale respiratory metabolism at high CO 2 . Two main processes contributed to the reduction of CUE at high CO 2 : a reduced inhibition of leaf respiration by light and a diminished leaf mass ratio. This work highlights the relevance of measuring respiration in light and assessment of the CUE response to environment conditions. © 2016 John Wiley & Sons Ltd.

Is the World in a State of Climate Change Planetary Emergency?

NASA Astrophysics Data System (ADS)

Carter, Peter

2013-04-01

Leading climate change experts have made public statements that the world is beyond dangerous interference with the climate system, committed to a warming of 3-5°C, facing a risk of global climate catastrophe, and in a state of planetary emergency, but these conclusions are not informing climate change policy. The evidence for these statements is examined and presented in this paper. The main parameters considered are world food security and carbon feedback "runaway" or rapid global warming. 2012 was a record year for Arctic albedo loss, which amplifies Arctic warming and drives Arctic methane feedback emissions. Since 2007, atmospheric methane is experiencing a renewed, sustained increase due to feedback emissions. All potentially large positive Arctic feedbacks are operant. These include albedo loss from disappearing snow and summer sea ice; methane released from peatlands, thawing permafrost and sea floor methane hydrates; and nitrous oxide from cryoperturbed permafrost. Increasing extreme weather events have caused regional crop productivity losses on many continents since 2000. The loss of Arctic albedo might be driving extreme heat and drought in the northern hemisphere. Today the formal national pledges for emissions reductions filed with the UN, combined, commit humanity to a warming of 4.4°C (Climate Interactive) by 2100, which is more than 8°C eventually after 2100, and there are no initiatives to change this. The International Energy Agency warns that the current global economy is on track for a warming of 6°C by 2100. A simple yet novel summation approach of all unavoidable sources of warming estimates the committed unavoidable warming to be 3°C by 2100. What are the implications of these future commitments for world food security and the risk of runaway climate change? The paper considers how these commitments and the policy-relevant research findings can inform policy making with respect to an appropriate science-based mitigation response.

Air quality and climate benefits of long-distance electricity transmission in China

NASA Astrophysics Data System (ADS)

Peng, Wei; Yuan, Jiahai; Zhao, Yu; Lin, Meiyun; Zhang, Qiang; Victor, David G.; Mauzerall, Denise L.

2017-06-01

China is the world’s top carbon emitter and suffers from severe air pollution. It has recently made commitments to improve air quality and to peak its CO2 emissions by 2030. We examine one strategy that can potentially address both issues—utilizing long-distance electricity transmission to bring renewable power to the polluted eastern provinces. Based on an integrated assessment using state-of-the-science atmospheric modeling and recent epidemiological evidence, we find that transmitting a hybrid of renewable (60%) and coal power (40%) (Hybrid-by-wire) reduces 16% more national air-pollution-associated deaths and decreases three times more carbon emissions than transmitting only coal-based electricity. Moreover, although we find that transmitting coal power (Coal-by-Wire, CbW) is slightly more effective at reducing air pollution impacts than replacing old coal power plants with newer cleaner ones in the east (Coal-by-Rail, CbR) (CbW achieves a 6% greater reduction in national total air-pollution-related mortalities than CbR), both coal scenarios have approximately the same carbon emissions. We thus demonstrate that coordinating transmission planning with renewable energy deployment is critical to maximize both local air quality benefits and global climate benefits.

Limited emission reductions from fuel subsidy removal except in energy-exporting regions.

PubMed

Jewell, Jessica; McCollum, David; Emmerling, Johannes; Bertram, Christoph; Gernaat, David E H J; Krey, Volker; Paroussos, Leonidas; Berger, Loïc; Fragkiadakis, Kostas; Keppo, Ilkka; Saadi, Nawfal; Tavoni, Massimo; van Vuuren, Detlef; Vinichenko, Vadim; Riahi, Keywan

2018-02-07

Hopes are high that removing fossil fuel subsidies could help to mitigate climate change by discouraging inefficient energy consumption and levelling the playing field for renewable energy. In September 2016, the G20 countries re-affirmed their 2009 commitment (at the G20 Leaders' Summit) to phase out fossil fuel subsidies and many national governments are using today's low oil prices as an opportunity to do so. In practical terms, this means abandoning policies that decrease the price of fossil fuels and electricity generated from fossil fuels to below normal market prices. However, whether the removal of subsidies, even if implemented worldwide, would have a large impact on climate change mitigation has not been systematically explored. Here we show that removing fossil fuel subsidies would have an unexpectedly small impact on global energy demand and carbon dioxide emissions and would not increase renewable energy use by 2030. Subsidy removal would reduce the carbon price necessary to stabilize greenhouse gas concentration at 550 parts per million by only 2-12 per cent under low oil prices. Removing subsidies in most regions would deliver smaller emission reductions than the Paris Agreement (2015) climate pledges and in some regions global subsidy removal may actually lead to an increase in emissions, owing to either coal replacing subsidized oil and natural gas or natural-gas use shifting from subsidizing, energy-exporting regions to non-subsidizing, importing regions. Our results show that subsidy removal would result in the largest CO 2 emission reductions in high-income oil- and gas-exporting regions, where the reductions would exceed the climate pledges of these regions and where subsidy removal would affect fewer people living below the poverty line than in lower-income regions.

Limited emission reductions from fuel subsidy removal except in energy-exporting regions

NASA Astrophysics Data System (ADS)

Jewell, Jessica; McCollum, David; Emmerling, Johannes; Bertram, Christoph; Gernaat, David E. H. J.; Krey, Volker; Paroussos, Leonidas; Berger, Loïc; Fragkiadakis, Kostas; Keppo, Ilkka; Saadi, Nawfal; Tavoni, Massimo; van Vuuren, Detlef; Vinichenko, Vadim; Riahi, Keywan

2018-02-01

Hopes are high that removing fossil fuel subsidies could help to mitigate climate change by discouraging inefficient energy consumption and levelling the playing field for renewable energy. In September 2016, the G20 countries re-affirmed their 2009 commitment (at the G20 Leaders’ Summit) to phase out fossil fuel subsidies and many national governments are using today’s low oil prices as an opportunity to do so. In practical terms, this means abandoning policies that decrease the price of fossil fuels and electricity generated from fossil fuels to below normal market prices. However, whether the removal of subsidies, even if implemented worldwide, would have a large impact on climate change mitigation has not been systematically explored. Here we show that removing fossil fuel subsidies would have an unexpectedly small impact on global energy demand and carbon dioxide emissions and would not increase renewable energy use by 2030. Subsidy removal would reduce the carbon price necessary to stabilize greenhouse gas concentration at 550 parts per million by only 2-12 per cent under low oil prices. Removing subsidies in most regions would deliver smaller emission reductions than the Paris Agreement (2015) climate pledges and in some regions global subsidy removal may actually lead to an increase in emissions, owing to either coal replacing subsidized oil and natural gas or natural-gas use shifting from subsidizing, energy-exporting regions to non-subsidizing, importing regions. Our results show that subsidy removal would result in the largest CO2 emission reductions in high-income oil- and gas-exporting regions, where the reductions would exceed the climate pledges of these regions and where subsidy removal would affect fewer people living below the poverty line than in lower-income regions.

Committed carbon emissions, deforestation, and community land conversion from oil palm plantation expansion in West Kalimantan, Indonesia.

PubMed

Carlson, Kimberly M; Curran, Lisa M; Ratnasari, Dessy; Pittman, Alice M; Soares-Filho, Britaldo S; Asner, Gregory P; Trigg, Simon N; Gaveau, David A; Lawrence, Deborah; Rodrigues, Hermann O

2012-05-08

Industrial agricultural plantations are a rapidly increasing yet largely unmeasured source of tropical land cover change. Here, we evaluate impacts of oil palm plantation development on land cover, carbon flux, and agrarian community lands in West Kalimantan, Indonesian Borneo. With a spatially explicit land change/carbon bookkeeping model, parameterized using high-resolution satellite time series and informed by socioeconomic surveys, we assess previous and project future plantation expansion under five scenarios. Although fire was the primary proximate cause of 1989-2008 deforestation (93%) and net carbon emissions (69%), by 2007-2008, oil palm directly caused 27% of total and 40% of peatland deforestation. Plantation land sources exhibited distinctive temporal dynamics, comprising 81% forests on mineral soils (1994-2001), shifting to 69% peatlands (2008-2011). Plantation leases reveal vast development potential. In 2008, leases spanned ∼65% of the region, including 62% on peatlands and 59% of community-managed lands, yet <10% of lease area was planted. Projecting business as usual (BAU), by 2020 ∼40% of regional and 35% of community lands are cleared for oil palm, generating 26% of net carbon emissions. Intact forest cover declines to 4%, and the proportion of emissions sourced from peatlands increases 38%. Prohibiting intact and logged forest and peatland conversion to oil palm reduces emissions only 4% below BAU, because of continued uncontrolled fire. Protecting logged forests achieves greater carbon emissions reductions (21%) than protecting intact forests alone (9%) and is critical for mitigating carbon emissions. Extensive allocated leases constrain land management options, requiring trade-offs among oil palm production, carbon emissions mitigation, and maintaining community landholdings.

Committed carbon emissions, deforestation, and community land conversion from oil palm plantation expansion in West Kalimantan, Indonesia

PubMed Central

Carlson, Kimberly M.; Curran, Lisa M.; Ratnasari, Dessy; Pittman, Alice M.; Soares-Filho, Britaldo S.; Asner, Gregory P.; Trigg, Simon N.; Gaveau, David A.; Lawrence, Deborah; Rodrigues, Hermann O.

2012-01-01

Industrial agricultural plantations are a rapidly increasing yet largely unmeasured source of tropical land cover change. Here, we evaluate impacts of oil palm plantation development on land cover, carbon flux, and agrarian community lands in West Kalimantan, Indonesian Borneo. With a spatially explicit land change/carbon bookkeeping model, parameterized using high-resolution satellite time series and informed by socioeconomic surveys, we assess previous and project future plantation expansion under five scenarios. Although fire was the primary proximate cause of 1989–2008 deforestation (93%) and net carbon emissions (69%), by 2007–2008, oil palm directly caused 27% of total and 40% of peatland deforestation. Plantation land sources exhibited distinctive temporal dynamics, comprising 81% forests on mineral soils (1994–2001), shifting to 69% peatlands (2008–2011). Plantation leases reveal vast development potential. In 2008, leases spanned ∼65% of the region, including 62% on peatlands and 59% of community-managed lands, yet <10% of lease area was planted. Projecting business as usual (BAU), by 2020 ∼40% of regional and 35% of community lands are cleared for oil palm, generating 26% of net carbon emissions. Intact forest cover declines to 4%, and the proportion of emissions sourced from peatlands increases 38%. Prohibiting intact and logged forest and peatland conversion to oil palm reduces emissions only 4% below BAU, because of continued uncontrolled fire. Protecting logged forests achieves greater carbon emissions reductions (21%) than protecting intact forests alone (9%) and is critical for mitigating carbon emissions. Extensive allocated leases constrain land management options, requiring trade-offs among oil palm production, carbon emissions mitigation, and maintaining community landholdings. PMID:22523241

Benefits of collaborative and comparative research on land use change and climate mitigation

NASA Astrophysics Data System (ADS)

Zhu, Zhiliang; Gong, Peng

2016-04-01

The world's two largest economies are also the latest greenhouse gas emitters. The United States is committed to reduce the net greenhouse gas emission by 28% below the 2005 level by 2025. Similarly China also announced significant climate mitigation steps at the Paris climate convention. These policy plans will require actions including reduction of GHG emissions as well as protection of carbon stored in biologic pools and increase of carbon sequestration by the natural ecosystems. Major drivers of ecosystem carbon sequestration and protection of existing carbon resources include land use, disturbances, and climate change. Recent studies indicate that vegetated ecosystems in the United States remain as a carbon sink but the sink is weakening due to increased disturbances (such as wildfire and harvesting) and aging of forests. Unique land use policies in China such as large-scale afforestation in the recent decades have reportedly led to significant increase in total forest area and aboveground biomass, although it is not clear to what degree the increase has translated to strengthened net uptake of atmospheric CO2 and the rate of sequestration by vegetated ecosystems. What lessons can we draw from different land management and land use practices in the U.S. and China that can benefit scientific advances and climate mitigation goals? Research conducted collaboratively by the U.S. Geological Survey and China Ministry of Science and Technology has led to improved techniques for tracking and modeling land use change and ecosystem disturbances and improved understanding of consequences of different land use change and management practices on ecosystem carbon sequestration capacities.

Could US mayors achieve the entire US Paris climate target?

NASA Astrophysics Data System (ADS)

Gurney, K. R.; Huang, J.; Hutchins, M.; Liang, J.

2017-12-01

After the recent US Federal Administration announcement not to adhere to the Paris Accords, 359 mayors (and counting) in the US pledged to maintain their commitments, reducing emissions within their jurisdictions by 26-28% from their 2005 levels by the year 2025. While important, this leaves a large portion of the US landscape, and a large amount of US emissions, outside of the Paris commitment. With Federal US policy looking unlikely to change, could additional effort by US cities overcome the gap in national policy and achieve the equivalent US national Paris commitment? How many cities would be required and how deep would reductions need to be? Up until now, this question could not be reliably resolved due to lack of data at the urban scale. Here, we answer this question with new data - the Vulcan V3.0 FFCO2 emissions data product - through examination of the total US energy related CO2 emissions from cities. We find that the top 500 urban areas in the US could meet the national US commitment to the Paris Accords with a reduction of roughly 30% below their 2015 levels by the year 2025. This is driven by the share of US emissions emanating from cities, particularly the largest cohort. Indeed, as the number of urban areas taking on CO2 reduction targets grows, the less the reduction burden on any individual city. In this presentation, we provide an analysis of US urban CO2 emissions and US climate policy, accounting for varying definitions of urban areas, emitting sectors and the tradeoff between the number of policy-active cities and the CO2 reduction burden.

Pollution mitigation and carbon sequestration by an urban forest.

PubMed

Brack, C L

2002-01-01

At the beginning of the 1900s, the Canberra plain was largely treeless. Graziers had carried out extensive clearing of the original trees since the 1820s leaving only scattered remnants and some plantings near homesteads. With the selection of Canberra as the site for the new capital of Australia, extensive tree plantings began in 1911. These trees have delivered a number of benefits, including aesthetic values and the amelioration of climatic extremes. Recently, however, it was considered that the benefits might extend to pollution mitigation and the sequestration of carbon. This paper outlines a case study of the value of the Canberra urban forest with particular reference to pollution mitigation. This study uses a tree inventory, modelling and decision support system developed to collect and use data about trees for tree asset management. The decision support system (DISMUT) was developed to assist in the management of about 400,000 trees planted in Canberra. The size of trees during the 5-year Kyoto Commitment Period was estimated using DISMUT and multiplied by estimates of value per square meter of canopy derived from available literature. The planted trees are estimated to have a combined energy reduction, pollution mitigation and carbon sequestration value of US$20-67 million during the period 2008-2012.

Providing Decision-Relevant Information for a State Climate Change Action Plan

NASA Astrophysics Data System (ADS)

Wake, C.; Frades, M.; Hurtt, G. C.; Magnusson, M.; Gittell, R.; Skoglund, C.; Morin, J.

2008-12-01

Carbon Solutions New England (CSNE), a public-private partnership formed to promote collective action to achieve a low carbon society, has been working with the Governor appointed New Hampshire Climate Change Policy Task Force (NHCCTF) to support the development of a state Climate Change Action Plan. CSNE's role has been to quantify the potential carbon emissions reduction, implementation costs, and cost savings at three distinct time periods (2012, 2025, 2050) for a range of strategies identified by the Task Force. These strategies were developed for several sectors (transportation and land use, electricity generation and use, building energy use, and agriculture, forestry, and waste).New Hampshire's existing and projected economic and population growth are well above the regional average, creating additional challenges for the state to meet regional emission reduction targets. However, by pursuing an ambitious suite of renewable energy and energy efficiency strategies, New Hampshire may be able to continue growing while reducing emissions at a rate close to 3% per year up to 2025. This suite includes efficiency improvements in new and existing buildings, a renewable portfolio standard for electricity generation, avoiding forested land conversion, fuel economy gains in new vehicles, and a reduction in vehicle miles traveled. Most (over 80%) of these emission reduction strategies are projected to provide net economic savings in 2025.A collaborative and iterative process was developed among the key partners in the project. The foundation for the project's success included: a diverse analysis team with leadership that was committed to the project, an open source analysis approach, weekly meetings and frequent communication among the partners, interim reporting of analysis, and an established and trusting relationship among the partners, in part due to collaboration on previous projects.To develop decision-relevant information for the Task Force, CSNE addressed several challenges, including: allocating the emission reduction and economic impacts of local- to state-scale mitigation strategies that are in reality integrated on regional and/or national scales; incorporating changes to the details of the strategies over time; identifying and quantifying key variables; choosing appropriate levels of detail for over 100 strategies within the limited analysis timeframe; integrating individual strategies into a coherent whole; and structuring data presentation to maximize transparency of analysis without confusing or overwhelming decision makers.

Early action to reduce greenhouse gas emissions before the commitment period of the Kyoto protocol: advantages and disadvantages.

PubMed

Michaelowa, A; Rolfe, C

2001-09-01

Current "business as usual" projections suggest greenhouse gas emissions from industrialized nations will grow substantially over the next decade. However, if it comes into force, the Kyoto Protocol will require industrialized nations to reduce emissions to an average of 5% below 1990 levels in the 2008-2012 period. Taking early action to close this gap has a number of advantages. It reduces the risks of passing thresholds that trigger climate change "surprises." Early action also increases future generations' ability to choose greater levels of climate protection, and it leads to faster reductions of other pollutants. From an economic sense, early action is important because it allows shifts to less carbon-intensive technologies during the course of normal capital stock turnover. Moreover, many options for emission reduction have negative costs, and thus are economically worthwhile, because of paybacks in energy costs, healthcare costs, and other benefits. Finally, early emission reductions enhance the probability of successful ratification and lower the risk of noncompliance with the protocol. We discuss policy approaches for the period prior to 2008. Disadvantages of the current proposals for Credit for Early Action are the possibility of adverse selection due to problematic baseline calculation methods as well as the distributionary impacts of allocating a part of the emissions budget already before 2008. One simple policy without drawbacks is the so-called baseline protection, which removes the disincentive to early action due to the expectation that businesses may, in the future, receive emission rights in proportion to past emissions. It is particularly important to adopt policies that shift investment in long-lived capital stock towards less carbon-intensive technologies and to encourage innovation and technology development that will reduce future compliance costs.

In-Use Emissions and Estimated Impacts of Traditional, Natural- and Forced-Draft Cookstoves in Rural Malawi

PubMed Central

2017-01-01

Emissions from traditional cooking practices in low- and middle-income countries have detrimental health and climate effects; cleaner-burning cookstoves may provide “co-benefits”. Here we assess this potential via in-home measurements of fuel-use and emissions and real-time optical properties of pollutants from traditional and alternative cookstoves in rural Malawi. Alternative cookstove models were distributed by existing initiatives and include a low-cost ceramic model, two forced-draft cookstoves (FDCS; Philips HD4012LS and ACE-1), and three institutional cookstoves. Among household cookstoves, emission factors (EF; g (kg wood)−1) were lowest for the Philips, with statistically significant reductions relative to baseline of 45% and 47% for fine particulate matter (PM2.5) and carbon monoxide (CO), respectively. The Philips was the only cookstove tested that showed significant reductions in elemental carbon (EC) emission rate. Estimated health and climate cobenefits of alternative cookstoves were smaller than predicted from laboratory tests due to the effects of real-world conditions including fuel variability and nonideal operation. For example, estimated daily PM intake and field-measurement-based global warming commitment (GWC) for the Philips FDCS were a factor of 8.6 and 2.8 times higher, respectively, than those based on lab measurements. In-field measurements provide an assessment of alternative cookstoves under real-world conditions and as such likely provide more realistic estimates of their potential health and climate benefits than laboratory tests. PMID:28060518

Teleconsultations reduce greenhouse gas emissions.

PubMed

Oliveira, Tiago Cravo; Barlow, James; Gonçalves, Luís; Bayer, Steffen

2013-10-01

Health services contribute significantly to greenhouse gas emissions. New models of delivering care closer to patients have the potential to reduce travelling and associated emissions. We aimed to compare the emissions of patients attending a teleconsultation - an outpatient appointment using video-conferencing equipment - with those of patients attending a face-to-face appointment. We estimated the total distances travelled and the direct and indirect greenhouse gas emissions for 20,824 teleconsultations performed between 2004 and 2011 in Alentejo, a Portuguese region. These were compared to the distances and emissions that would have resulted if teleconsultations were not available and patients had to attend face-to-face outpatient appointments. Estimates were calculated using survey data on mode of transport, and national aggregate data for car engine size and fuel. A sensitivity analysis using the lower and upper quartiles for survey distances was performed. Teleconsultations led to reductions in distances and emissions of 95%. 2,313,819 km of travelling and 455 tonnes of greenhouse gas emissions were avoided (22 kg of carbon dioxide equivalent per patient). The incorporation of modes of transport and car engine size and fuel in the analysis led to emission estimates which were 12% smaller than those assuming all patients used an average car. The availability of remote care services can significantly reduce road travel and associated emissions. At a time when many countries are committed to reducing their carbon footprint, it is desirable to explore how these reductions could be incorporated into technology assessments and economic evaluations.

Employing a CGE model in analysing the environmental and economy-wide impacts of CO2 emission abatement policies in Malaysia.

PubMed

Yahoo, Masoud; Othman, Jamal

2017-04-15

The impact of global warming has received much international attention in recent decades. To meet climate-change mitigation targets, environmental policy instruments have been designed to transform the way goods and services are produced as well as alter consumption patterns. The government of Malaysia is strongly committed to reducing CO 2 gas emissions as a proportion of GDP by 40% from 2005 levels by the year 2020. This study evaluates the economy-wide impacts of implementing two different types of CO 2 emission abatement policies in Malaysia using market-based (imposing a carbon tax) and command-and-control mechanism (sectoral emission standards). The policy simulations conducted involve the removal of the subsidy on petroleum products by the government. A carbon emission tax in conjunction with the revenue neutrality assumption is seen to be more effective than a command-and-control policy as it provides a double dividend. This is apparent as changes in consumption patterns lead to welfare enhancements while contributing to reductions in CO 2 emissions. The simulation results show that the production of renewable energies is stepped up when the imposition of carbon tax and removal of the subsidy is augmented by revenue recycling. This study provides an economy-wide assessment that compares two important tools for assisting environment policy makers evaluate carbon emission abatement initiatives in Malaysia. Copyright © 2017 Elsevier B.V. All rights reserved.

Antecedents of Student Teachers' Affective Commitment to the Teaching Profession and Turnover Intention

ERIC Educational Resources Information Center

Christophersen, Knut-Andreas; Elstad, Eyvind; Solhaug, Trond; Turmo, Are

2016-01-01

Several European countries have experienced both a dearth of and reduction in the quality of applicants to teacher education study programmes. There is also significant leakage from these programmes. The rationale for this study therefore lies in the need to reduce teacher attrition. Research indicates that affective commitment to a profession is…

Using a Class to Conduct a Carbon Inventory: A Case Study with Practical Results at Macalester College

ERIC Educational Resources Information Center

Wells, Christopher W.; Savanick, Suzanne; Manning, Christie

2009-01-01

Purpose: The purpose of this paper is to discuss the practical realities of using a college seminar to fulfill the carbon audit requirement for signatories to the American College and University Presidents Climate Commitment (ACUPCC) and presents evidence of this approach's advantages as an educational and practical tool.…

The relationship between some demographic characteristics and organizational commitment of nurses working in the Social Security Hospital of Khorramabad

PubMed Central

Sepahvand, Faribah; Atashzadeh-Shoorideh, Foorozan; Parvizy, Soroor; Tafreshi, Mansoureh Zagheri

2017-01-01

Background Reduction in organizational commitment of nurses results in deficiency of care services. Some demographic factors affect organizational commitment. Objective The present study is intended to determine the organizational commitment of nurses and its relationship with demographic characteristics. Methods This study was a descriptive correlation (cross-sectional) study in January and February of 2016 on 126 nurses who held Bachelor of Science (B.Sc.) or Master of Science (M.Sc.) and at least one year of work experience in the Social Security Hospital of Khorramabad, selected using the census method. Data collection tools included a demographic characteristics form and Allen and Meyer questionnaire. Data analysis was performed using SPSS 20. Independent-samples t-test and one-way ANOVA were used to determine the relationship between organizational commitment and demographic characteristics. Results The majority of nurses had moderate organizational commitment, the highest score belonging to the continuance commitment (22.33%), and the lowest score belonging to the normative commitment (19.16%). Also, there was a significant correlation between the continuance commitment and work experience (p=0.001), the staff posts (p=0.01) and shifts (p=0.04). Conclusion Considering the moderate level of subjects’ organizational commitment in the present study, managers should take necessary measures to increase the attachment and organizational commitment of nurses and provide the ground for improving nursing services. PMID:28848623

The relationship between some demographic characteristics and organizational commitment of nurses working in the Social Security Hospital of Khorramabad.

PubMed

Sepahvand, Faribah; Atashzadeh-Shoorideh, Foorozan; Parvizy, Soroor; Tafreshi, Mansoureh Zagheri

2017-06-01

Reduction in organizational commitment of nurses results in deficiency of care services. Some demographic factors affect organizational commitment. The present study is intended to determine the organizational commitment of nurses and its relationship with demographic characteristics. This study was a descriptive correlation (cross-sectional) study in January and February of 2016 on 126 nurses who held Bachelor of Science (B.Sc.) or Master of Science (M.Sc.) and at least one year of work experience in the Social Security Hospital of Khorramabad, selected using the census method. Data collection tools included a demographic characteristics form and Allen and Meyer questionnaire. Data analysis was performed using SPSS 20. Independent-samples t-test and one-way ANOVA were used to determine the relationship between organizational commitment and demographic characteristics. The majority of nurses had moderate organizational commitment, the highest score belonging to the continuance commitment (22.33%), and the lowest score belonging to the normative commitment (19.16%). Also, there was a significant correlation between the continuance commitment and work experience (p=0.001), the staff posts (p=0.01) and shifts (p=0.04). Considering the moderate level of subjects' organizational commitment in the present study, managers should take necessary measures to increase the attachment and organizational commitment of nurses and provide the ground for improving nursing services.

Assessing the Feasibility of Comprehensive Energy Efficiency Upgrades at Potawatomi Carter Casino Hotel

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

Karman, Nathan A.

The Forest County Potawatomi Community, a federally-recognized Indian Tribe with a strong commitment to the natural environment, sought and obtained funding to investigate energy efficient improvements to its Potawatomi Carter Casino & Hotel and the adjacent Potawatomi Carter C-Store and Smoke Shop. The resulting energy studies recommended energy conservation measures that would collectively reduce energy use by more than 30% at the facilities and would save approximately $200,000 per year in energy costs. Consistent with its commitment to the natural environment, and to advance its goal of energy independence using Carbon free or Carbon neutral renewable resources, the Community hasmore » already begun implementing certain measures and continues to seek funding sources necessary to implement the remaining measures.« less

A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

NASA Astrophysics Data System (ADS)

Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, Chandrasekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

2016-12-01

Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts.

Interannual variation of carbon fluxes from three contrasting evergreen forests: the role of forest dynamics and climate.

PubMed

Sierra, Carlos A; Loescher, Henry W; Harmon, Mark E; Richardson, Andrew D; Hollinger, David Y; Perakis, Steven S

2009-10-01

Interannual variation of carbon fluxes can be attributed to a number of biotic and abiotic controls that operate at different spatial and temporal scales. Type and frequency of disturbance, forest dynamics, and climate regimes are important sources of variability. Assessing the variability of carbon fluxes from these specific sources can enhance the interpretation of past and current observations. Being able to separate the variability caused by forest dynamics from that induced by climate will also give us the ability to determine if the current observed carbon fluxes are within an expected range or whether the ecosystem is undergoing unexpected change. Sources of interannual variation in ecosystem carbon fluxes from three evergreen ecosystems, a tropical, a temperate coniferous, and a boreal forest, were explored using the simulation model STANDCARB. We identified key processes that introduced variation in annual fluxes, but their relative importance differed among the ecosystems studied. In the tropical site, intrinsic forest dynamics contributed approximately 30% of the total variation in annual carbon fluxes. In the temperate and boreal sites, where many forest processes occur over longer temporal scales than those at the tropical site, climate controlled more of the variation among annual fluxes. These results suggest that climate-related variability affects the rates of carbon exchange differently among sites. Simulations in which temperature, precipitation, and radiation varied from year to year (based on historical records of climate variation) had less net carbon stores than simulations in which these variables were held constant (based on historical records of monthly average climate), a result caused by the functional relationship between temperature and respiration. This suggests that, under a more variable temperature regime, large respiratory pulses may become more frequent and high enough to cause a reduction in ecosystem carbon stores. Our results also show that the variation of annual carbon fluxes poses an important challenge in our ability to determine whether an ecosystem is a source, a sink, or is neutral in regard to CO2 at longer timescales. In simulations where climate change negatively affected ecosystem carbon stores, there was a 20% chance of committing Type II error, even with 20 years of sequential data.

Committed warming inferred from observations and an energy balance model

NASA Astrophysics Data System (ADS)

Pincus, R.; Mauritsen, T.

2017-12-01

Due to the lifetime of CO2 and thermal inertia of the ocean, the Earth's climate is not equilibrated with anthropogenic forcing. As a result, even if fossil fuel emissions were to suddenly cease, some level of committed warming is expected due to past emissions. Here, we provide an observational-based quantification of this committed warming using the instrument record of global-mean warming, recently-improved estimates of Earth's energy imbalance, and estimates of radiative forcing from the fifth IPCC assessment report. Compared to pre-industrial levels, we find a committed warming of 1.5K [0.9-3.6, 5-95 percentile] at equilibrium, and of 1.3K [0.9-2.3] within this century. However, when assuming that ocean carbon uptake cancels remnant greenhouse gas-induced warming on centennial timescales, committed warming is reduced to 1.1K [0.7-1.8]. Conservatively, there is a 32% risk that committed warming already exceeds the 1.5K target set in Paris, and that this will likely be crossed prior to 2053. Regular updates of these observationally-constrained committed warming estimates, though simplistic, can provide transparent guidance as uncertainty regarding transient climate sensitivity inevitably narrows and understanding the limitations of the framework is advanced.

Potential reduction exposure products and FDA tobacco and regulation: a CNS call to action.

PubMed

Heath, Janie; Andrews, Jeannette; Balkstra, Cindy R

2004-01-01

A new generation of tobacco harm reduction products is stirring controversy and confusion among healthcare providers. These products, known as "potential reduction exposure products" (PREPs), can be described in terms of reported scientific evidence, as "the good, the bad, and the ugly." On the good side, there is sufficient scientific evidence to support the use of Commit, a new over-the-counter nicotine lozenge PREP, approved for smoking cessation. On the bad side, there is no scientific evidence to support the use of Ariva, another over-the-counter nicotine lozenge PREP, marketed as an alternative to cigarettes when smoking is restricted. On the ugly side, both of these PREPs are nicotine delivery systems with "candy-like" appearances; however, one (Commit) has the Food and Drug Administration (FDA) approval and the other (Ariva) does not. This article provides an overview of PREPs and strategies to help clinical nurse specialists (CNSs) address tobacco harm reduction issues.

Variability in climate change simulations affects needed long-term riverine nutrient reductions for the Baltic Sea.

PubMed

Bring, Arvid; Rogberg, Peter; Destouni, Georgia

2015-06-01

Changes to runoff due to climate change may influence management of nutrient loading to the sea. Assuming unchanged river nutrient concentrations, we evaluate the effects of changing runoff on commitments to nutrient reductions under the Baltic Sea Action Plan. For several countries, climate projections point to large variability in load changes in relation to reduction targets. These changes either increase loads, making the target more difficult to reach, or decrease them, leading instead to a full achievement of the target. The impact of variability in climate projections varies with the size of the reduction target and is larger for countries with more limited commitments. In the end, a number of focused actions are needed to manage the effects of climate change on nutrient loads: reducing uncertainty in climate projections, deciding on frameworks to identify best performing models with respect to land surface hydrology, and increasing efforts at sustained monitoring of water flow changes.

Variability in climate change simulations affects needed long-term riverine nutrient reductions for the Baltic Sea

DOE PAGES

Bring, Arvid; Rogberg, Peter; Destouni, Georgia

2015-05-28

Changes to runoff due to climate change may influence management of nutrient loading to the sea. Assuming unchanged river nutrient concentrations, we evaluate the effects of changing runoff on commitments to nutrient reductions under the Baltic Sea Action Plan. For several countries, climate projections point to large variability in load changes in relation to reduction targets. These changes either increase loads, making the target more difficult to reach, or decrease them, leading instead to a full achievement of the target. The impact of variability in climate projections varies with the size of the reduction target and is larger for countriesmore » with more limited commitments. Finally, in the end, a number of focused actions are needed to manage the effects of climate change on nutrient loads: reducing uncertainty in climate projections, deciding on frameworks to identify best performing models with respect to land surface hydrology, and increasing efforts at sustained monitoring of water flow changes.« less

Variability in climate change simulations affects needed long-term riverine nutrient reductions for the Baltic Sea

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

Bring, Arvid; Rogberg, Peter; Destouni, Georgia

Changes to runoff due to climate change may influence management of nutrient loading to the sea. Assuming unchanged river nutrient concentrations, we evaluate the effects of changing runoff on commitments to nutrient reductions under the Baltic Sea Action Plan. For several countries, climate projections point to large variability in load changes in relation to reduction targets. These changes either increase loads, making the target more difficult to reach, or decrease them, leading instead to a full achievement of the target. The impact of variability in climate projections varies with the size of the reduction target and is larger for countriesmore » with more limited commitments. Finally, in the end, a number of focused actions are needed to manage the effects of climate change on nutrient loads: reducing uncertainty in climate projections, deciding on frameworks to identify best performing models with respect to land surface hydrology, and increasing efforts at sustained monitoring of water flow changes.« less

Global economic consequences of deploying bioenergy with carbon capture and storage (BECCS)

NASA Astrophysics Data System (ADS)

Muratori, Matteo; Calvin, Katherine; Wise, Marshall; Kyle, Page; Edmonds, Jae

2016-09-01

Bioenergy with carbon capture and storage (BECCS) is considered a potential source of net negative carbon emissions and, if deployed at sufficient scale, could help reduce carbon dioxide emissions and concentrations. However, the viability and economic consequences of large-scale BECCS deployment are not fully understood. We use the Global Change Assessment Model (GCAM) integrated assessment model to explore the potential global and regional economic impacts of BECCS. As a negative-emissions technology, BECCS would entail a net subsidy in a policy environment in which carbon emissions are taxed. We show that by mid-century, in a world committed to limiting climate change to 2 °C, carbon tax revenues have peaked and are rapidly approaching the point where climate mitigation is a net burden on general tax revenues. Assuming that the required policy instruments are available to support BECCS deployment, we consider its effects on global trade patterns of fossil fuels, biomass, and agricultural products. We find that in a world committed to limiting climate change to 2 °C, the absence of CCS harms fossil-fuel exporting regions, while the presence of CCS, and BECCS in particular, allows greater continued use and export of fossil fuels. We also explore the relationship between carbon prices, food-crop prices and use of BECCS. We show that the carbon price and biomass and food crop prices are directly related. We also show that BECCS reduces the upward pressure on food crop prices by lowering carbon prices and lowering the total biomass demand in climate change mitigation scenarios. All of this notwithstanding, many challenges, both technical and institutional, remain to be addressed before BECCS can be deployed at scale.

A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

PubMed Central

Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, ChandraSekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

2016-01-01

Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts. PMID:27958290

Salmonella Enteritidis Deposition inside Eggs after Experimental Infection of Laying Hens with Different Oral Doses

USDA-ARS?s Scientific Manuscript database

The continuing attribution of human Salmonella Enteritidis infections to internally contaminated eggs has necessitated the commitment of substantial public and private resources to risk reduction and testing programs for commercial laying flocks. Cost-effective risk reduction requires a detailed und...

[Cerebellar Infarction After Carbon Monoxide Poisoning and Hyperbaric Oxygen Therapy].

PubMed

Wick, Matthias; Schneiker, André; Bele, Sylvia; Pawlik, Michael; Meyringer, Helmut; Graf, Bernhard; Wendl, Christina; Kieninger, Martin

2017-06-01

We report on a patient who developed a space-occupying cerebellar infarction with occlusive hydrocephalus after a poisoning with carbon monoxide with the intention to commit suicide. A neurosurgical and intensive care therapy were needed. The patient's survival without severe neurological deficits could be secured due to the early detection of the intracerebral lesions. Georg Thieme Verlag KG Stuttgart · New York.

Sulfate reduction and oxic respiration in marine sediments: implications for organic carbon preservation in euxinic environments

NASA Technical Reports Server (NTRS)

Canfield, D. E.; DeVincenzi, D. L. (Principal Investigator)

1989-01-01

Compilations have been made of sulfate reduction rates and oxic respiration rates over the entire range of marine sedimentation rates, and sedimentary environments, including several euxinic sites. These data show, consistent with the findings of Jorgensen (1982, Nature, 296, 643-645), that sulfate reduction and oxic respiration oxidize equal amounts of organic carbon in nearshore sediments. As sedimentation rates decrease, oxic respiration, becomes progressively more important, and in deep-sea sediments 100-1000 times more organic carbon is oxidized by oxic respiration than by sulfate reduction. By contrast, nearly as much organic carbon is oxidized by sulfate reduction in euxinic sediments as is oxidized by the sum of sulfate reduction and oxic respiration in normal marine sediments of similar deposition rate. This observation appears at odds with the enhanced preservation of organic carbon observed in euxinic sediments. However, only small reductions in (depth-integrated) organic carbon decomposition rates (compared to normal marine) are required to give both high organic carbon concentrations and enhanced carbon preservation in euxinic sediments. Lower rates of organic carbon decomposition (if only by subtle amounts) are explained by the diminished ability of anaerobic bacteria to oxidize the full suite of sedimentary organic compounds.

Awareness of Stress-reduction Interventions: The Impact on Employees' Well-being and Organizational Attitudes.

PubMed

Pignata, Silvia; Boyd, Carolyn; Gillespie, Nicole; Provis, Christopher; Winefield, Anthony H

2016-08-01

Employing the social-exchange theoretical framework, we examined the effect of employees' awareness of stress-reduction interventions on their levels of psychological strain, job satisfaction, organizational commitment, perceptions of senior management trustworthiness and procedural justice. We present longitudinal panel data from 869 employees who completed questionnaires at two time points at 13 Australian universities. Our results show that employees who reported an awareness of stress-reduction interventions undertaken at their university scored lower on psychological strain and higher on job satisfaction and commitment than those who were unaware of the interventions. The results suggest that simply the awareness of stress interventions can be linked to positive employee outcomes. The study further revealed that senior management trustworthiness and procedural justice mediate the relationship between awareness and employee outcomes. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

The Oregon Court of Appeals and the State Civil Commitment Statute.

PubMed

Bloom, Joseph D; Britton, Juliet; Berry, Wil

2017-03-01

In 1973 the Oregon Legislature passed a major revision of its civil commitment law adopting changes that mirrored those taking place across the United States. The new sections offered significant protections of the rights of individuals who are alleged to have mental illness, a limitation on the length of commitment, the adoption of both dangerousness and gravely disabled type commitment criteria and the adoption of "beyond a reasonable doubt" as the standard of proof for commitment hearings. From 1973 to the present time, the Oregon Court of Appeals adjudicated a large number of appeals emanating from civil commitment courts. This article is based on a review of 98 written Oregon Court of Appeals commitment decisions from the years 1998 through 2015 and is accompanied by a review of legislative intent in 1973. It appears that the court of appeals has significantly altered the 1973 legislative changes by moving the dangerousness criteria to imminence and the gravely disabled criteria to a focus on survival. Empirically, civil commitment has dramatically decreased in Oregon over a 40-year period and the case law, as developed by Oregon Court of Appeals, has had a significant contributing role in this reduction. © 2017 American Academy of Psychiatry and the Law.

40 CFR 60.2115 - What if I do not use a wet scrubber, fabric filter, activated carbon injection, selective...

Code of Federal Regulations, 2014 CFR

2014-07-01

..., fabric filter, activated carbon injection, selective noncatalytic reduction, an electrostatic... filter, activated carbon injection, selective noncatalytic reduction, an electrostatic precipitator, or a... than a wet scrubber, activated carbon injection, selective noncatalytic reduction, fabric filter, an...

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

Grissom, C.B.; Cleland, W.W.

The role of the metal ion in the oxidative decarboxylation of malate by chicken liver NADP malic enzyme and details of the reaction mechanism have been investigated by /sup 13/C isotope effects. With saturating NADP and the indicated metal ion at a total concentration 10-fold higher than its K/sub m/, the following primary /sup 13/C kinetic isotope effects at C/sub 4/ of malate (/sup 13/(VK/sub mal/)) were observed at pH 8.0: Mg/sup 2 +/, 1.0336; Mn/sup 2 +/, 1.0365; Cd/sup 2 +/, 1.0366; Zn/sup 2 +/, 1.0337; Co/sup 2 +/, 1.0283; Ni/sup 2 +/, 1.025. Knowing the partitioning of themore » intermediate oxalacetate between decarboxylation to pyuvate and reduction to malate allows calculation of the intrinsic carbon isotope effect for decarboxylation to pyuvate and reduction to malate allows calculation of the intrinsic carbon isotope effect for decarboxylation. For Mg/sup 2 +/ as activator, this was 1.049 with NADP and 1.046 with 3-acetylpyridine adenine dinucleotide phosphate, although the intrinsic primary deuterium isotope effects on dehydrogenation were 5.6 and 4.2, and the partition ratios of the oxalacetate intermediate for decarboxylation as opposed to hydride transfer were 0.11 and 3.96. It was not possible to calculate reasonable intrinsic carbon isotope effects with the other metal ions by use of the partitioning ratio of oxalacetate because of decarboxylation by another mechanism. The variation of /sup 13/(VK/sub mal/) with pH was used to dissect the total forward and external components. When the authors attempted to use the variation of /sup 13/(VK/sub mal/) with solution viscosity to determine the internal and external commitments, incorrect values were obtained because of a specific effect of the viscosogen in decreasing the K/sub m/ for malate, so that VK/sub mal/ actually increased with viscosity instead of decreasing, as theory predicts.« less

A mathematical/physics carbon emission reduction strategy for building supply chain network based on carbon tax policy

NASA Astrophysics Data System (ADS)

Li, Xueying; Peng, Ying; Zhang, Jing

2017-03-01

Under the background of a low carbon economy, this paper examines the impact of carbon tax policy on supply chain network emission reduction. The integer linear programming method is used to establish a supply chain network emission reduction such a model considers the cost of CO2 emissions, and analyses the impact of different carbon price on cost and carbon emissions in supply chains. The results show that the implementation of a carbon tax policy can reduce CO2 emissions in building supply chain, but the increase in carbon price does not produce a reduction effect, and may bring financial burden to the enterprise. This paper presents a reasonable carbon price range and provides decision makers with strategies towards realizing a low carbon building supply chain in an economical manner.

Committed warming inferred from observations

NASA Astrophysics Data System (ADS)

Mauritsen, Thorsten; Pincus, Robert

2017-09-01

Due to the lifetime of CO2, the thermal inertia of the oceans, and the temporary impacts of short-lived aerosols and reactive greenhouse gases, the Earth’s climate is not equilibrated with anthropogenic forcing. As a result, even if fossil-fuel emissions were to suddenly cease, some level of committed warming is expected due to past emissions as studied previously using climate models. Here, we provide an observational-based quantification of this committed warming using the instrument record of global-mean warming, recently improved estimates of Earth’s energy imbalance, and estimates of radiative forcing from the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Compared with pre-industrial levels, we find a committed warming of 1.5 K (0.9-3.6, 5th-95th percentile) at equilibrium, and of 1.3 K (0.9-2.3) within this century. However, when assuming that ocean carbon uptake cancels remnant greenhouse gas-induced warming on centennial timescales, committed warming is reduced to 1.1 K (0.7-1.8). In the latter case there is a 13% risk that committed warming already exceeds the 1.5 K target set in Paris. Regular updates of these observationally constrained committed warming estimates, although simplistic, can provide transparent guidance as uncertainty regarding transient climate sensitivity inevitably narrows and the understanding of the limitations of the framework is advanced.

Effect of Amount of Carbon on the Reduction Efficiency of Iron Ore-Coal Composite Pellets in Multi-layer Bed Rotary Hearth Furnace (RHF)

NASA Astrophysics Data System (ADS)

Mishra, Srinibash; Roy, Gour Gopal

2016-08-01

The effect of carbon-to-hematite molar ratio has been studied on the reduction efficiency of iron ore-coal composite pellet reduced at 1523 K (1250 °C) for 20 minutes in a laboratory scale multi-layer bed rotary hearth furnace (RHF). Reduced pellets have been characterized through weight loss measurement, estimation of porosity, shrinkage, qualitative and quantitative phase analysis by XRD. Performance parameters such as the degree of reduction, metallization, carbon efficiency, productivity, and compressive strength have been calculated to compare the process efficacy at different carbon levels in the pellets. Pellets with optimum carbon-to-hematite ratio (C/Fe2O3 molar ratio = 1.66) that is much below the stoichiometric carbon required for direct reduction of hematite yielded maximum reduction, better carbon utilization, and productivity for all three layers. Top layer exhibited maximum reduction at comparatively lower carbon level (C/Fe2O3 molar ratio <2.33) in the pellet, while bottom layer exceeded top layer reduction at higher carbon level (C/Fe2O3 molar ratio >2.33). Correlation between degree of reduction and metallization indicated non-isothermal kinetics influenced by heat and mass transfer in multi-layer bed RHF. Compressive strength of the partially reduced pellet with optimum carbon content (C/Fe2O3 molar ratio = 1.66) showed that they could be potentially used as an alternate feed in a blast furnace or any other smelting reactor.

[Awareness of health co-benefits of carbon emissions reduction in urban residents in Beijing: a cross-sectional survey].

PubMed

Gao, J H; Zhang, Y; Wang, J; Chen, H J; Zhang, G B; Liu, X B; Wu, H X; Li, J; Li, J; Liu, Q Y

2017-05-10

Objective: To understand the awareness of the health co-benefits of carbon emission reduction in urban residents in Beijing and the influencing factors, and provide information for policy decision on carbon emission reduction and health education campaigns. Methods: Four communities were selected randomly from Fangshan, Haidian, Huairou and Dongcheng districts of Beijing, respectively. The sample size was estimated by using Kish-Leslie formula for descriptive analysis. 90 participants were recruited from each community. χ (2) test was conducted to examine the associations between socio-demographic variables and individuals' awareness of the health co-benefits of carbon emission reduction. Ordinal logistic regression analysis was performed to investigate the factors influencing the awareness about the health co-benefits. Results: In 369 participants surveyed, 12.7 % reported they knew the health co-benefits of carbon emission reduction. The final logistic regression analysis revealed that age ( OR =0.98), attitude to climate warming ( OR =0.72) and air pollution ( OR =1.59), family monthly average income ( OR =1.27), and low carbon lifestyle ( OR =2.36) were important factors influencing their awareness of the health co-benefits of carbon emission reduction. Conclusion: The awareness of the health co-benefits of carbon emissions reduction were influenced by people' socio-demographic characteristics (age and family income), concerns about air pollution and climate warming, and low carbon lifestyle. It is necessary to take these factors into consideration in future development and implementation of carbon emission reduction policies and related health education campaigns.

Iron Reduction and Carbonate Precipitation by Shewanella oneidensis

NASA Astrophysics Data System (ADS)

Zeng, Z.; Tice, M. M.

2011-12-01

This study is to contribute to better understanding of how Archean microbes induced carbonate diagenesis in mats and stromatolites. Previous studies showed sulfate reduction, a common promoter of carbonate precipitation in modern mats[1], is likely to have been less effective in Archean mats in marine fluids lower in sulfate[2]. Alternatively, iron reduction produces far more alkalinity per unit carbon respired than sulfate reduction. Therefore, we hypothesize iron reduction can promote much more carbonate precipitation than sulfate reduction. Our study might also have some relevance to banded iron formation on which microbial iron reduction played a potential role[3]. To test our hypothesis, Shewanella oneidensis MR-1, a dissimilatory iron reducing bacterium will be cultured anaerobically (79%N2, 20%CO2 and 1%H2) in basal medium to trigger iron reduction. Lactate will be used as electron donor, and the electron acceptor will be fresh ferrihydrite. Culture medium will be added with various metal ions, such as Ca2+ and Mg2+, to obtain potential carbonate precipitate. Escherichia coli (with fumarate added as an electron acceptor) will be used to provide a comparison to live but non-iron- reduction cells. After 20 days incubation, precipitate will be collected, washed and identified by X-ray diffraction (XRD). Besides, iron reduction rate (ferrozine assay)[4], PH and amount of precipitate (carbonate and oxidize fractions)[5] will be measured over time to well understand how S. oneidensis drives carbonate precipitation.

[Efficiency of industrial energy conservation and carbon emission reduction in Liaoning Pro-vince based on data envelopment analysis (DEA)method.

PubMed

Wang, Li; Xi, Feng Ming; Li, Jin Xin; Liu, Li Li

2016-09-01

Taking 39 industries as independent decision-making units in Liaoning Province from 2003 to 2012 and considering the benefits of energy, economy and environment, we combined direction distance function and radial DEA method to estimate and decompose the energy conservation and carbon emissions reduction efficiency of the industries. Carbon emission of each industry was calculated and defined as an undesirable output into the model of energy saving and carbon emission reduction efficiency. The results showed that energy saving and carbon emission reduction efficiency of industries had obvious heterogeneity in Liaoning Province. The whole energy conservation and carbon emissions reduction efficiency in each industry of Liaoning Province was not high, but it presented a rising trend. Improvements of pure technical efficiency and scale efficiency were the main measures to enhance energy saving and carbon emission reduction efficiency, especially scale efficiency improvement. In order to improve the energy saving and carbon emission reduction efficiency of each industry in Liaoning Province, we put forward that Liaoning Province should adjust industry structure, encourage the development of low carbon high benefit industries, improve scientific and technological level and adjust the industry scale reasonably, meanwhile, optimize energy structure, and develop renewable and clean energy.

WTO Dispute Settlement: Status of U.S. Compliance in Pending Cases

DTIC Science & Technology

2010-01-29

meat , poultry meat , and rice, for 2008 and 2009.183 Brazil’s request was based on language in the Arbitrator’s report directing the United States to...subsidy commitments regarding various unscheduled products (e.g., cotton, oilseeds, protein meals) as well as three scheduled products (rice, poultry ... meat , and rice).148 By providing export subsidies both to unscheduled products and to scheduled products in excess of its reduction commitments, the

A Biochemical Magic Frequency Based on the Reduction Level of Biological Carbon

NASA Technical Reports Server (NTRS)

Weber, Arthur L.

1995-01-01

We have calculated the average number of electron pairs required for the chemical reduction of carbon dioxide to biological carbon using (a) estimates of the reducing equivalents (electron pairs) needed to synthesize biomolecules from carbon dioxide, and (b) measurements of the molecular composition of different organisms. These calculations showed that the carbon of the Earth's biosphere is at the reduction level of formaldehyde that requires two electron pairs per carbon atom to be synthesized from carbon dioxide. This was also the reduction level of cellular carbon when fuel stored as lipid was not used in the estimate. Since this chemical characteristic of life is probably universal, it could be the one thing we know about other carbon-based life in the universe, and the one thing that other intelligent life knows about us. We believe that this common knowledge that biological carbon throughout the universe is at the reduction level of formaldehyde could lead to the selection of the 72.83814 GHz line of the 0, 0, 0 yields 1, 1, 1 rotational transition of formaldehyde as a frequency for interstellar communication.

Semiconductor-Based Photoelectrochemical Conversion of Carbon Dioxide: Stepping Towards Artificial Photosynthesis.

PubMed

Pang, Hong; Masuda, Takuya; Ye, Jinhua

2018-01-18

The photoelectrochemical (PEC) carbon dioxide reduction process stands out as a promising avenue for the conversion of solar energy into chemical feedstocks, among various methods available for carbon dioxide mitigation. Semiconductors derived from cheap and abundant elements are interesting candidates for catalysis. Whether employed as intrinsic semiconductors or hybridized with metallic cocatalysts, biocatalysts, and metal molecular complexes, semiconductor photocathodes exhibit good performance and low overpotential during carbon dioxide reduction. Apart from focusing on carbon dioxide reduction materials and chemistry, PEC cells towards standalone devices that use photohybrid electrodes or solar cells have also been a hot topic in recent research. An overview of the state-of-the-art progress in PEC carbon dioxide reduction is presented and a deep understanding of the catalysts of carbon dioxide reduction is also given. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Trash to Gas (TtG) Simulant Analysis

NASA Technical Reports Server (NTRS)

Miles, John D., II; Hintze, Paul E.

2014-01-01

Space exploration in outer earths orbit is a long-term commitment, where the reuse of discarded materials is a critical component for its success. The Logistics Reduction and Repurposing (LRR) project under the NASA Advanced Exploration System Program is a project focused on technologies that reduce the amount of consumables that are needed to be sent into space, repurpose items sent to space, or convert wastes to commodities. In particular, Trash to Gas (TtG), part of the LRR project, is a novel space technology capable of converting raw elements from combustible waste including food waste and packaging, paper, wipes and towels, nitrile gloves, fecal matter, urine brine, maximum absorbency garments, and other organic wastes from human space exploration into useful gases. Trash to gas will ultimately reduce mission cost by producing a portion of important consumables in situ. This paper will discuss results of waste processing by steam reforming. Steam reforming is a thermochemical process developed as part of TtG, where waste is heated in the presence of oxygen and steam to produce carbon dioxide, carbon monoxide, hydrogen, methane and water. The aim of this experiment is to investigate the processing of different waste simulants and their gaseous products. This will lay a foundation for understating and optimizing the production of useful gases for propulsion and recovery of water for life support.

Joint implementation: Biodiversity and greenhouse gas offsets

NASA Astrophysics Data System (ADS)

Cutright, Noel J.

1996-11-01

One of the most pressing environmental issues today is the possibility that projected increases in global emissions of greenhouse gases from increased deforestation, development, and fossil-fuel combustion could significantly alter global climate patterns. Under the terms of the United Nations Framework Convention on Climate Change, signed in Rio de Janeiro during the June 1992 Earth Summit, the United States and other industrialized countries committed to balancing greenhouse gas emissions at 1990 levels in the year 2000. Included in the treaty is a provision titled “Joint Implementation,” whereby industrialized countries assist developing countries in jointly modifying long-term emission trends, either through emission reductions or by protecting and enhancing greenhouse gas sinks (carbon sequestration). The US Climate Action Plan, signed by President Clinton in 1993, calls for voluntary climate change mitigation measures by various sectors, and the action plan included a new program, the US Initiative on Joint Implementation. Wisconsin Electric decided to invest in a Jl project because its concept encourages creative, cost-effective solutions to environmental problems through partnering, international cooperation, and innovation. The project chosen, a forest preservation and management effort in Belize, will sequester more than five million tons of carbon dioxide over a 40-year period, will become economically selfsustaining after ten years, and will have substantial biodiversity benefits.

Effects of Low-Dose Mindfulness-Based Stress Reduction (MBSR-ld) on Working Adults

ERIC Educational Resources Information Center

Klatt, Maryanna D.; Buckworth, Janet; Malarkey, William B.

2009-01-01

Mindfulness-based stress reduction (MBSR) has produced behavioral, psychological, and physiological benefits, but these programs typically require a substantial time commitment from the participants. This study assessed the effects of a shortened (low-dose [ld]) work-site MBSR intervention (MBSR-ld) on indicators of stress in healthy working…

Canada's Voluntary ARET Program: Limited Success Despite Industry Cosponsorship

ERIC Educational Resources Information Center

Antweiler, Werner; Harrison, Kathryn

2007-01-01

The Accelerated Reduction/Elimination of Toxins (ARET) Challenge was a voluntary program initiated in 1994 by the Government of Canada. Unlike the U.S. 33/50 Program, ARET involved industry partners in negotiation and cosponsorship of the program, with the intention that early involvement would yield stronger commitment to voluntary reductions. We…

Acceptance and Commitment Therapy for Problematic Internet Pornography Use: A Randomized Trial.

PubMed

Crosby, Jesse M; Twohig, Michael P

2016-05-01

Problematic Internet pornography use is the inability to control the use of pornography, the experience of negative cognitions or emotions regarding pornography use, and the resulting negative effects on quality of life or general functioning. This study compared a 12-session individual protocol of acceptance and commitment therapy (ACT) for problematic Internet pornography use to a waitlist control condition with 28 adult males, all but 1 of whom were members of the Church of Jesus Christ of Latter-day Saints. Measures of self-reported pornography viewing, standardized measures of compulsive sexual behavior and related cognitions, and quality of life occurred at pretreatment, posttreatment, and 3-month follow-up. Results demonstrate significant between-condition reductions in pornography viewing compared to the waitlist condition (93% reduction ACT vs. 21% waitlist). When combining all participants (N=26), a 92% reduction was seen at posttreatment and an 86% reduction at 3-month follow-up. Complete cessation was seen in 54% of participants at posttreatment and at least a 70% reduction was seen in 93% of participants. At the 3-month follow-up assessment, 35% of participants showed complete cessation, with 74% of participants showing at least 70% reduction in viewing. Treatment suggestions and future directions are discussed. Copyright © 2016. Published by Elsevier Ltd.

[Research on carbon reduction potential of electric vehicles for low-carbon transportation and its influencing factors].

PubMed

Shi, Xiao-Qing; Li, Xiao-Nuo; Yang, Jian-Xin

2013-01-01

Transportation is the key industry of urban energy consumption and carbon emissions. The transformation of conventional gasoline vehicles to new energy vehicles is an important initiative to realize the goal of developing low-carbon city through energy saving and emissions reduction, while electric vehicles (EV) will play an important role in this transition due to their advantage in energy saving and lower carbon emissions. After reviewing the existing researches on energy saving and emissions reduction of electric vehicles, this paper analyzed the factors affecting carbon emissions reduction. Combining with electric vehicles promotion program in Beijing, the paper analyzed carbon emissions and reduction potential of electric vehicles in six scenarios using the optimized energy consumption related carbon emissions model from the perspective of fuel life cycle. The scenarios included power energy structure, fuel type (energy consumption per 100 km), car type (CO2 emission factor of fuel), urban traffic conditions (speed), coal-power technologies and battery type (weight, energy efficiency). The results showed that the optimized model was able to estimate carbon emissions caused by fuel consumption more reasonably; electric vehicles had an obvious restrictive carbon reduction potential with the fluctuation of 57%-81.2% in the analysis of six influencing factors, while power energy structure and coal-power technologies play decisive roles in life-cycle carbon emissions of electric vehicles with the reduction potential of 78.1% and 81.2%, respectively. Finally, some optimized measures were proposed to reduce transport energy consumption and carbon emissions during electric vehicles promotion including improving energy structure and coal technology, popularizing energy saving technologies and electric vehicles, accelerating the battery R&D and so on. The research provides scientific basis and methods for the policy development for the transition of new energy vehicles in low-carbon transport.

Acceptance and commitment therapy as a treatment for problematic internet pornography viewing.

PubMed

Twohig, Michael P; Crosby, Jesse M

2010-09-01

Despite the prevalence of problematic Internet pornography viewing and the breadth of intervention approaches to potentially address it, no studies to address this problem have been reported to date. An emerging treatment approach, Acceptance and Commitment Therapy (ACT), holds promise as a treatment for Internet pornography viewing because of its focus on processes hypothesized to underlie this maladaptive behavior. In the first experiment on the treatment of problematic Internet pornography viewing, 6 adult males who reported that their Internet pornography viewing was affecting their quality of life were treated in eight 1.5-hour sessions of ACT for problematic pornography viewing. The effects of the intervention were assessed in a multiple-baseline-across-participants design with time viewing pornography as the dependent variable. Treatment resulted in an 85% reduction in viewing at posttreatment with results being maintained at 3-month follow-up (83% reduction). Increases were seen on measures of quality of life, and reductions were seen on measures of OCD and scrupulosity. Weekly measures of ACT-consistent processes showed reductions that corresponded with reductions in viewing. Large reductions were seen on a measure of psychological flexibility, and minor reductions were seen on measures of thought-action fusion and thought control. Overall, results suggest the promise of ACT as a treatment for problematic Internet pornography viewing and the value of future randomized trials of this approach.

Interannual variation of carbon fluxes from three contrasting evergreen forests: The role of forest dynamics and climate

USGS Publications Warehouse

Sierra, C.A.; Loescher, H.W.; Harmon, M.E.; Richardson, A.D.; Hollinger, D.Y.; Perakis, S.S.

2009-01-01

Interannual variation of carbon fluxes can be attributed to a number of biotic and abiotic controls that operate at different spatial and temporal scales. Type and frequency of disturbance, forest dynamics, and climate regimes are important sources of variability. Assessing the variability of carbon fluxes from these specific sources can enhance the interpretation of past and current observations. Being able to separate the variability caused by forest dynamics from that induced by climate will also give us the ability to determine if the current observed carbon fluxes are within an expected range or whether the ecosystem is undergoing unexpected change. Sources of interannual variation in ecosystem carbon fluxes from three evergreen ecosystems, a tropical, a temperate coniferous, and a boreal forest, were explored using the simulation model STANDCARB. We identified key processes that introduced variation in annual fluxes, but their relative importance differed among the ecosystems studied. In the tropical site, intrinsic forest dynamics contributed ?? 30% of the total variation in annual carbon fluxes. In the temperate and boreal sites, where many forest processes occur over longer temporal scales than those at the tropical site, climate controlled more of the variation among annual fluxes. These results suggest that climate-related variability affects the rates of carbon exchange differently among sites. Simulations in which temperature, precipitation, and radiation varied from year to year (based on historical records of climate variation) had less net carbon stores than simulations in which these variables were held constant (based on historical records of monthly average climate), a result caused by the functional relationship between temperature and respiration. This suggests that, under a more variable temperature regime, large respiratory pulses may become more frequent and high enough to cause a reduction in ecosystem carbon stores. Our results also show that the variation of annual carbon fluxes poses an important challenge in our ability to determine whether an ecosystem is a source, a sink, or is neutral in regard to CO2 at longer timescales. In simulations where climate change negatively affected ecosystem carbon stores, there was a 20% chance of committing Type II error, even with 20 years of sequential data. ?? 2009 by the Ecological Society of America.

Long term (1987-2012) trends in water chemistry of acid sensitive Swedish lakes

NASA Astrophysics Data System (ADS)

Futter, Martyn; Valinia, Salar; Fölster, Jens

2014-05-01

Acidification of surface waters is a serious concern in Sweden. During the 1970s and 1980s, many surface waters in Sweden were acidified by long-range pollution. Legislated emissions reductions have led to the recovery of many water bodies but today, there are concerns about the possibility of re-acidification. Sweden is committed to a goal of natural acidification only (i.e. no anthropogenic acidification). Here, we present long term (1987-2012) trends in strong acid anion, base cation, organic carbon and alkalinity measurements. Lakes are defined as acidified in Sweden if pH is more than 0.4 units less than a reference (1860) pH estimated using MAGIC, a widely used process-based model of acidification. Using this criteria, many acid sensitive Swedish lakes are still acidified. A changing climate and more intensive forest harvesting may further delay the recovery from acidification. Average measured alkalinity in the 38 lakes presented here was <= 0.02 mekv/l between 2000-2012. Strong acid anion concentrations declined, primarily as a result of declines in sulfate. Chloride is now the dominant anion in many of these lakes. Base cations concentrations have declined less rapidly, leading to an increase in charge balance ANC. This increase in charge balance ANC has not been matched by an increase in measured alkalinity. Total organic carbon concentrations have increased significantly in many of these lakes, to the point where modeled organic acidity is now approximately equal to inorganic acidity. While the results presented here conform to acidification theory, they illustrate the value of long-term monitoring for assessing the effects of pollutant reduction measures, identifying new threats to water quality and corroborating model results. Most importantly, the long-term monitoring results presented here can be an important tool for informing environmental policy.

Pathways of organic carbon oxidation in three continental margin sediments

NASA Technical Reports Server (NTRS)

Canfield, D. E.; Jorgensen, B. B.; Fossing, H.; Glud, R.; Gundersen, J.; Ramsing, N. B.; Thamdrup, B.; Hansen, J. W.; Nielsen, L. P.; Hall, P. O.

1993-01-01

We have combined several different methodologies to quantify rates of organic carbon mineralization by the various electron acceptors in sediments from the coast of Denmark and Norway. Rates of NH4+ and Sigma CO2 liberation sediment incubations were used with O2 penetration depths to conclude that O2 respiration accounted for only between 3.6-17.4% of the total organic carbon oxidation. Dentrification was limited to a narrow zone just below the depth of O2 penetration, and was not a major carbon oxidation pathway. The processes of Fe reduction, Mn reduction and sulfate reduction dominated organic carbon mineralization, but their relative significance varied depending on the sediment. Where high concentrations of Mn-oxide were found (3-4 wt% Mn), only Mn reduction occurred. With lower Mn oxide concentrations more typical of coastal sediments, Fe reduction and sulfate reduction were most important and of a similar magnitude. Overall, most of the measured O2 flux into the sediment was used to oxidized reduced inorganic species and not organic carbon. We suspect that the importance of O2 respiration in many coastal sediments has been overestimated, whereas metal oxide reduction (both Fe and Mn reduction) has probably been well underestimated.

Estimating geological CO2 storage security to deliver on climate mitigation.

PubMed

Alcalde, Juan; Flude, Stephanie; Wilkinson, Mark; Johnson, Gareth; Edlmann, Katriona; Bond, Clare E; Scott, Vivian; Gilfillan, Stuart M V; Ogaya, Xènia; Haszeldine, R Stuart

2018-06-12

Carbon capture and storage (CCS) can help nations meet their Paris CO 2 reduction commitments cost-effectively. However, lack of confidence in geologic CO 2 storage security remains a barrier to CCS implementation. Here we present a numerical program that calculates CO 2 storage security and leakage to the atmosphere over 10,000 years. This combines quantitative estimates of geological subsurface CO 2 retention, and of surface CO 2 leakage. We calculate that realistically well-regulated storage in regions with moderate well densities has a 50% probability that leakage remains below 0.0008% per year, with over 98% of the injected CO 2 retained in the subsurface over 10,000 years. An unrealistic scenario, where CO 2 storage is inadequately regulated, estimates that more than 78% will be retained over 10,000 years. Our modelling results suggest that geological storage of CO 2 can be a secure climate change mitigation option, but we note that long-term behaviour of CO 2 in the subsurface remains a key uncertainty.

Active capping technology: a new environmental remediation of contaminated sediment.

PubMed

Zhang, Chang; Zhu, Meng-Ying; Zeng, Guang-Ming; Yu, Zhi-Gang; Cui, Fang; Yang, Zhong-Zhu; Shen, Liu-Qing

2016-03-01

The management and treatment of contaminated sediment is a worldwide problem and poses major technical and economic challenges. Nowadays, various attempts have been committed to investigating a cost-effective way in contaminated sediment restoration. Among the remediation options, in situ capping turns out to be a less expensive, less disruptive, and more durable approach. However, by using the low adsorption capacity materials, traditional caps do not always fulfill the reduction of risks that can be destructive for human health, ecosystem, and even natural resources. Active caps, therefore, are designed to employ active materials (activated carbon, apatite, zeolite, organoclay, etc.) to strengthen their adsorption and degradation capacity. The active capping technology promises to be a permanent and cost-efficient solution to contaminated sediments. This paper provides a review on the types of active materials and the ways of these active materials employed in recent active capping studies. Cap design considerations including site-specific conditions, diffusion/advection, erosive forces, and active material selection that should be noticed in an eligible remediation project are also presented.

Specification of Energy Assessment Methodologies to Satisfy ISO 50001 Energy Management Standard

NASA Astrophysics Data System (ADS)

Kanneganti, Harish

Energy management has become more crucial for industrial sector as a way to lower their cost of production and in reducing their carbon footprint. Environmental regulations also force the industrial sector to increase the efficiency of their energy usage. Hence industrial sector started relying on energy management consultancies for improvements in energy efficiency. With the development of ISO 50001 standard, the entire energy management took a new dimension involving top level management and getting their commitment on energy efficiency. One of the key requirements of ISO 50001 is to demonstrate continual improvement in their (industry) energy efficiency. The major aim of this work is to develop an energy assessment methodology and reporting format to tailor the needs of ISO 50001. The developed methodology integrates the energy reduction aspect of an energy assessment with the requirements of sections 4.4.3 (Energy Review) to 4.4.6 (Objectives, Targets and Action Plans) in ISO 50001 and thus helping the facilities in easy implementation of ISO 50001.

Ontario's Primary Class Size Reduction Initiative: Report on Early Implementation

ERIC Educational Resources Information Center

Bascia, Nina

2010-01-01

Reduction in the size of classes from Kindergarten to Grade 3 was a major Liberal Party campaign promise in Ontario's 2003 provincial election. It was intended to demonstrate a new government's commitment to improving public education. By the 2008-09 school year, the provincial government's goals had been achieved: over 90% of all primary classes…

A Descriptive Evaluation of the Federal Class-Size Reduction Program: Final Report

ERIC Educational Resources Information Center

Millsap, Mary Ann; Giancola, Jennifer; Smith, W. Carter; Hunt, Dana; Humphrey, Daniel C.; Wechsler, Marjorie E.; Riehl, Lori M.

2004-01-01

The federal Class-Size Reduction (CSR) Program, P.L. 105-277, begun in Fiscal Year 1999, represented a major federal commitment to help school districts hire additional qualified teachers, especially in the early elementary grades, so children would learn in smaller classes. The CSR program also allowed funds to be spent as professional…

Impact assessment of the carbon reduction strategy for transport, low carbon transport : a greener future

DOT National Transportation Integrated Search

2009-07-01

This is an impact assessment for the Carbon Reduction Strategy for Transport (DfT, 2009), Low Carbon Transport: A Greener Future, which is part of the UK Governments wider UK Low Carbon Transition Plan (DECC, 2009), Britains path to ta...

Estimating the National Carbon Abatement Potential of City Policies: A Data-Driven Approach

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

O'Shaughnessy, Eric; Heeter, Jenny; Keyser, David

Cities are increasingly taking actions such as building code enforcement, urban planning, and public transit expansion to reduce emissions of carbon dioxide in their communities and municipal operations. However, many cities lack the quantitative information needed to estimate policy impacts and prioritize city actions in terms of carbon abatement potential and cost effectiveness. This report fills this research gap by providing methodologies to assess the carbon abatement potential of a variety of city actions. The methodologies are applied to an energy use data set of 23,458 cities compiled for the U.S. Department of Energy City Energy Profile tool. The analysismore » develops a national estimate of the carbon abatement potential of realizable city actions in six specific policy areas encompassing the most commonly implemented city actions. The results of this analysis suggest that, in aggregate, cities could reduce nationwide carbon emissions by about 210 million metric tons of carbon dioxide (MMT CO2) per year in a 'moderate abatement scenario' by 2035 and 480 MMT CO2/year in a 'high abatement scenario' by 2035 through these common actions typically within a city's control in the six policy areas. The aggregate carbon abatement potential of these specific areas equates to a reduction of 3%-7% relative to 2013 U.S. emissions. At the city level, the results suggest the average city could reduce carbon emissions by 7% (moderate) to 19% (high) relative to current city-level emissions. In the context of U.S. climate commitments under the 21st session of the Conference of the Parties (COP21), the estimated national abatement potential of the city actions analyzed in this report equates to about 15%-35% of the remaining carbon abatement necessary to achieve the U.S. COP21 target. Additional city actions outside the scope of this report, such as community choice aggregation (city-level purchasing of renewable energy), zero energy districts, and multi-level governance strategies, could significantly augment the carbon abatement contributions of city actions toward national climate targets. The results suggest that cities may play a pivotal role in progress toward national climate targets. In addition to providing carbon and emissions estimates, this report estimates the national net economic impacts of policies for which cost and benefit data are available. Impact metrics include employment, worker earnings, and gross domestic product (GDP). For the policy areas studied, the economic analysis demonstrates that city carbon abatement may be achieved with only minimal and generally slightly positive economic impacts. Employment impacts range from 0.04% to 0.13% of U.S, employment during implementation and zero to 0.1% thereafter. GDP estimates show net impacts of 0.02% to 0.07% of GDP during implementation and impacts from -0.02% to zero thereafter. This report quantitatively demonstrates the material impact of a limited set of local policy areas on national carbon abatement potential. The magnitude of estimated carbon reductions from city policies, 3%-7% of national emissions by 2035, suggests an important role for city-led actions in reaching U.S. climate goals. Multi-level governance at the city, state, and national levels could augment the carbon abatement potential of city actions and make cities a key component of long-term U.S. climate strategies.« less

40 CFR 60.2680 - What if I do not use a wet scrubber, fabric filter, activated carbon injection, selective...

Code of Federal Regulations, 2014 CFR

2014-07-01

..., fabric filter, activated carbon injection, selective noncatalytic reduction, an electrostatic... use a wet scrubber, fabric filter, activated carbon injection, selective noncatalytic reduction, an... reduction, fabric filter, an electrostatic precipitator, or a dry scrubber or limit emissions in some other...

40 CFR 60.2680 - What if I do not use a wet scrubber, fabric filter, activated carbon injection, selective...

Code of Federal Regulations, 2013 CFR

2013-07-01

..., fabric filter, activated carbon injection, selective noncatalytic reduction, an electrostatic... use a wet scrubber, fabric filter, activated carbon injection, selective noncatalytic reduction, an... reduction, fabric filter, an electrostatic precipitator, or a dry scrubber or limit emissions in some other...

Classroom Demonstration: Combustion of Diamond to Carbon Dioxide Followed by Reduction to Graphite

ERIC Educational Resources Information Center

Miyauchi, Takuya; Kamata, Masahiro

2012-01-01

An educational demonstration shows the combustion of carbon to carbon dioxide and then the reduction of carbon dioxide to carbon. A melee diamond is the source of the carbon and the reaction is carried out in a closed flask. The demonstration helps students to realize that diamonds are made of carbon and that atoms do not change or vanish in…

Defense Threat Reduction Agency > Careers > Onboarding

Science.gov Websites

, click HERE. Let's Get Started Our values allow personnel to achieve their commitment to total customer satisfaction by meeting and anticipating customer needs. INTEGRITY SERVICE EXCELLENCE INNOVATION TEAMWORK

What Can China Do? China's Best Alternative Outcome for Energy Efficiency and CO2 Emissions

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

G. Fridley, David; Zheng, Nina; T. Aden, Nathaniel

After rapid growth in economic development and energy demand over the last three decades, China has undertaken energy efficiency improvement efforts to reduce its energy intensity under the 11th Five Year Plan (FYP). Since becoming the world's largest annual CO{sub 2} emitter in 2007, China has set reduction targets for energy and carbon intensities and committed to meeting 15% of its total 2020 energy demand with non-fossil fuel. Despite having achieved important savings in 11th FYP efficiency programs, rising per capita income and the continued economic importance of trade will drive demand for transport activity and fuel use. At themore » same time, an increasingly 'electrified' economy will drive rapid power demand growth. Greater analysis is therefore needed to understand the underlying drivers, possible trajectories and mitigation potential in the growing industrial, transport and power sectors. This study uses scenario analysis to understand the likely trajectory of China's energy and carbon emissions to 2030 in light of the current and planned portfolio of programs, policies and technology development and ongoing urbanization and demographic trends. It evaluates the potential impacts of alternative transportation and power sector development using two key scenarios, Continued Improvement Scenario (CIS) and Accelerated Improvement Scenario (AIS). CIS represents the most likely path of growth based on continuation of current policies and meeting announced targets and goals, including meeting planned appliance efficiency standard revisions, fuel economy standards, and industrial targets and moderate phase-out of subcritical coal-fired generation with additional non-fossil generation. AIS represents a more aggressive trajectory of accelerated improvement in energy intensity and decarbonized power and transport sectors. A range of sensitivity analysis and power technology scenarios are tested to evaluate the impact of additional actions such as carbon capture and sequestration (CCS) and integrated mine-mouth generation. The CIS and AIS results are also contextualized and compared to model scenarios in other published studies. The results of this study show that China's energy and CO{sub 2} emissions will not likely peak before 2030, although growth is expected to slow after 2020. Moreover, China will be able to meet its 2020 carbon intensity reduction target of 40 to 45% under both CIS and AIS, but only meet its 15% non-fossil fuel target by 2020 under AIS. Under both scenarios, efficiency remains a key resource and has the same, if not greater, mitigation potential as new technologies in transport and power sectors. In the transport sector, electrification will be closely linked the degree of decarbonization in the power sector and EV deployment has little or no impact on China's crude oil import demand. Rather, power generation improvements have the largest sector potential for overall emission mitigation while mine-mouth power generation and CCS have limited mitigation potential compared to fuel switching and efficiency improvements. Comparisons of this study's results with other published studies reveal that CIS and AIS are within the range of other national energy projections but alternative studies rely much more heavily on CCS for carbon reduction. The McKinsey study, in particular, has more optimistic assumptions for reductions in crude oil imports and coal demand in its abatement scenario and has much higher gasoline reduction potential for the same level of EV deployment. Despite these differences, this study's scenario analysis of both transport and power sectors illustrate the necessity for continued efficiency improvements and aggressive power sector decarbonization in flattening China's CO{sub 2} emissions.« less

Rewiring the Carbon Economy: Engineered Carbon Reduction Listening Day Summary Report

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

Illing, Lauren; Natelson, Robert; Resch, Michael

On July 8, 2017, the U.S. Department of Energy’s Bioenergy Technologies Office (BETO) sponsored the Engineered Carbon Reduction Listening Day: Advanced Strategies to Bypass Land Use for the Emerging Bioeconomy in La Jolla, California. This event explored non-photosynthetic carbon dioxide–reduction technologies, including electrocatalytic, thermocatalytic, photocatalytic, and biocatalytic approaches. BETO has summarized stakeholder input from the listening day in a summary report.

The promise of spirit at work: increasing job satisfaction and organizational commitment and reducing turnover and absenteeism in long-term care.

PubMed

Kinjerski, Val; Skrypnek, Berna J

2008-10-01

The effectiveness of a spirit at work program in long-term care was evaluated using a quasi-experimental, pretest-posttest design. These findings, along with focus group results, provide strong support that the program increased spirit at work, job satisfaction, organizational commitment, and organizational culture (particularly teamwork and morale), leading to a reduction in turnover and absenteeism--two major concerns in the long-term care sector. This study suggests that implementation of a spirit at work program is a relatively inexpensive way to enhance the work satisfaction of employees, increase their commitment to the organization (thus reducing turnover and absenteeism), and ultimately improve the quality of resident care.

Modelling short-rotation coppice and tree planting for urban carbon management - a citywide analysis.

PubMed

McHugh, Nicola; Edmondson, Jill L; Gaston, Kevin J; Leake, Jonathan R; O'Sullivan, Odhran S

2015-10-01

The capacity of urban areas to deliver provisioning ecosystem services is commonly overlooked and underutilized. Urban populations have globally increased fivefold since 1950, and they disproportionately consume ecosystem services and contribute to carbon emissions, highlighting the need to increase urban sustainability and reduce environmental impacts of urban dwellers. Here, we investigated the potential for increasing carbon sequestration, and biomass fuel production, by planting trees and short-rotation coppice (SRC), respectively, in a mid-sized UK city as a contribution to meeting national commitments to reduce CO 2 emissions.Iterative GIS models were developed using high-resolution spatial data. The models were applied to patches of public and privately owned urban greenspace suitable for planting trees and SRC, across the 73 km 2 area of the city of Leicester. We modelled tree planting with a species mix based on the existing tree populations, and SRC with willow and poplar to calculate biomass production in new trees, and carbon sequestration into harvested biomass over 25 years.An area of 11 km 2 comprising 15% of the city met criteria for tree planting and had the potential over 25 years to sequester 4200 tonnes of carbon above-ground. Of this area, 5·8 km 2 also met criteria for SRC planting and over the same period this could yield 71 800 tonnes of carbon in harvested biomass.The harvested biomass could supply energy to over 1566 domestic homes or 30 municipal buildings, resulting in avoided carbon emissions of 29 236 tonnes of carbon over 25 years when compared to heating by natural gas. Together with the net carbon sequestration into trees, a total reduction of 33 419 tonnes of carbon in the atmosphere could be achieved in 25 years by combined SRC and tree planting across the city. Synthesis and applications . We demonstrate that urban greenspaces in a typical UK city are underutilized for provisioning ecosystem services by trees and especially SRC, which has high biomass production potential. For urban greenspace management, we recommend that planting SRC in urban areas can contribute to reducing food-fuel conflicts on agricultural land and produce renewable energy sources close to centres of population and demand.

Electrochemical reduction of carbon dioxide. Final report

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

LaConti, A.B.; Molter, T.M.; Zagaja, J.A.

1986-05-01

Many researchers have studied the electrochemical reduction of carbon dioxide and related organic species to form concentrated liquid/gaseous products in laboratory-scale hardware. Hamilton Standard has developed a high pressure SPE electrolysis cell capable of reducing carbon dioxide streams to form pure, concentrated alcohols, carboxylic acids, and other hydrocarbons. The process is unique in that the byproducts of reaction include oxygen and, under some test conditions water. In addition, a relatively simple test system was designed and constructed permitting both batch and semibatch type electrochemical reduction studies. In this study, cathode materials were developed which 1) had a characteristic high hydrogenmore » overvoltage, and 2) possessed the intrinsic affinity for electrochemical reduction of the carbon dioxide species. In addition, suitable anode electrocatalyst materials were identified. Studies involving the electrochemical reduction of carbon dioxide required the ability to identify and quantify reaction products obtained during cell evaluation. Gas chromatographic techniques were developed along with the establishment of ion chromatographic methods permitting the analysis of organic reaction products. Hamilton Standard has evaluated electrochemical carbon dioxide reduction cells under a variety of test conditions.« less

Reducing GHG emissions in the United States' transportation sector

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

Das, Sujit; Andress, David A; Nguyen, Tien

Reducing GHG emissions in the U.S. transportation sector requires both the use of highly efficient propulsion systems and low carbon fuels. This study compares reduction potentials that might be achieved in 2060 for several advanced options including biofuels, hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), and fuel cell electric vehicles (FCEV), assuming that technical and cost reduction targets are met and necessary fueling infrastructures are built. The study quantifies the extent of the reductions that can be achieved through increasing engine efficiency and transitioning to low-carbon fuels separately. Decarbonizing the fuels is essential for achieving large reductions inmore » GHG emissions, and the study quantifies the reductions that can be achieved over a range of fuel carbon intensities. Although renewables will play a vital role, some combination of coal gasification with carbon capture and sequestration, and/or nuclear energy will likely be needed to enable very large reductions in carbon intensities for hydrogen and electricity. Biomass supply constraints do not allow major carbon emission reductions from biofuels alone; the value of biomass is that it can be combined with other solutions to help achieve significant results. Compared with gasoline, natural gas provides 20% reduction in GHG emissions in internal combustion engines and up to 50% reduction when used as a feedstock for producing hydrogen or electricity, making it a good transition fuel for electric propulsion drive trains. The material in this paper can be useful information to many other countries, including developing countries because of a common factor: the difficulty of finding sustainable, low-carbon, cost-competitive substitutes for petroleum fuels.« less

Managing carbon sinks in rubber (Hevea brasilensis) plantation by changing rotation length in SW China.

PubMed

Nizami, Syed Moazzam; Yiping, Zhang; Liqing, Sha; Zhao, Wei; Zhang, Xiang

2014-01-01

Extension of the rotation length in forest management has been highlighted in Article 3.4 of the Kyoto Protocol to help the countries in their commitments for reduction in greenhouse gas emissions. CO2FIX Model Ver.3.2 was used to examine the dynamics of carbon stocks (C stocks) in a rubber plantation in South Western China with the changing rotation lengths. To estimate the efficiency of increasing the rotation length as an Article 3.4 activity, study predicted that the rubber production and C stocks of the ecosystem increased with the increasing rotation (25, 30, 35, 40 and 45 years). While comparing the pace of growth both in economical (rubber production) and ecological (C stocks) terms in each rotation, 40 years rotation length showed maximum production and C stocks. After elongation of 40 year rotation to four consecutive cycles, it was concluded that the total C stocks of the ecosystem were 186.65 Mg ha(-1). The longer rotation lengths showed comparatively increased C stocks in below ground C stock after consecutive four rotations. The pace of C input (Mg C ha(-1) yr(-1)) and rubber production indicated that 40 years rotation is best suited for rubber plantation. The study has developed carbon mitigation based on four rotation scenarios. The possible stimulated increase in C stocks of the entire ecosystem after consecutive long rotations indicated that the emphasis must be paid on deciding the rotation of rubber plantation in SW China for reporting under article 3.4 of the Kyoto Protocol.

Managing Carbon Sinks in Rubber (Hevea brasilensis) Plantation by Changing Rotation length in SW China

PubMed Central

Nizami, Syed Moazzam; Yiping, Zhang; Liqing, Sha; Zhao, Wei; Zhang, Xiang

2014-01-01

Extension of the rotation length in forest management has been highlighted in Article 3.4 of the Kyoto Protocol to help the countries in their commitments for reduction in greenhouse gas emissions. CO2FIX Model Ver.3.2 was used to examine the dynamics of carbon stocks (C stocks) in a rubber plantation in South Western China with the changing rotation lengths. To estimate the efficiency of increasing the rotation length as an Article 3.4 activity, study predicted that the rubber production and C stocks of the ecosystem increased with the increasing rotation (25, 30, 35, 40 and 45 years). While comparing the pace of growth both in economical (rubber production) and ecological (C stocks) terms in each rotation, 40 years rotation length showed maximum production and C stocks. After elongation of 40 year rotation to four consecutive cycles, it was concluded that the total C stocks of the ecosystem were 186.65 Mg ha-1. The longer rotation lengths showed comparatively increased C stocks in below ground C stock after consecutive four rotations. The pace of C input (Mg C ha-1yr-1) and rubber production indicated that 40years rotation is best suited for rubber plantation. The study has developed carbon mitigation based on four rotation scenarios. The possible stimulated increase in C stocks of the entire ecosystem after consecutive long rotations indicated that the emphasis must be paid on deciding the rotation of rubber plantation in SW China for reporting under article 3.4 of the Kyoto Protocol. PMID:25536041

Agenda and Meeting Summary from Final Workshop on Arctic Black Carbon: Reduction of Black Carbon from Diesel Sources

EPA Pesticide Factsheets

The U.S. Environmental Protection Agency, Battelle Memorial Institute and WWF-Russia organized the final workshop on Arctic Black Carbon: Reduction of Black Carbon from Diesel Sources on November 5, 2014 in Murmansk, Russia.

Agenda and Meeting Summary from Best Practices Training on Arctic Black Carbon: Reduction of Black Carbon from Diesel Sources

EPA Pesticide Factsheets

From April 15-19, 2013, EPA's partners hosted the Best Practices Training on Arctic Black Carbon: Reduction of Black Carbon from Diesel Sources in Murmansk, Russia. Over the course of this event, participants:

Carbon balance in municipal solid waste management--a case study of Nonthaburi municipality, Thailand.

PubMed

Nanthapong, Kampol; Polprasert, Chongchin

2013-12-01

This research aimed to investigate the carbon equivalences associated with the unit processes of municipal solid waste management (MSWM) in Nonthaburi municipality. In addition, factors affecting MSWM's carbon-related activities were determined to find the reduction potential of carbon emissions into the atmosphere. Afield survey was conducted to quantify the amount of resources used in MSWM. Then, they were evaluated in terms of carbon equivalences occurring in the process scheme and categorized into carbon emissions, fixation and reduction,following a carbon-balanced model. From carbon balance analysis of the base-line-scenario MSWM, the carbon emissions were found to be -2,374.56 MTCE/y, resulting in the average carbon unit of-22.98 kg CE/ton solid waste. The negative sign indicates a carbon reduction, instead of an emission,from this MSWM practice, which helps to reduce the concentration of carbon dioxide in the atmosphere. The results of the model reveal that the highest contribution to carbon reduction potential in MSWM is recycling. Accordingly, it is strongly recommended that a policy promoting reuse, recovery, and recycling be pursued in every step of MSWM to assist in, not only extending landfill service life span, but also alleviating the increasing global warming problems.

Measles mortality reduction contributes substantially to reduction of all cause mortality among children less than five years of age, 1990-2008.

PubMed

van den Ent, Maya M V X; Brown, David W; Hoekstra, Edward J; Christie, Athalia; Cochi, Stephen L

2011-07-01

The Millennium Development Goal 4 (MDG4) to reduce mortality in children aged <5 years by two-thirds from 1990 to 2015 has made substantial progress. We describe the contribution of measles mortality reduction efforts, including those spearheaded by the Measles Initiative (launched in 2001, the Measles Initiative is an international partnership committed to reducing measles deaths worldwide and is led by the American Red Cross, the Centers for Disease Control and Prevention, UNICEF, the United Nations Foundation, and the World Health Organization). We used published data to assess the effect of measles mortality reduction on overall and disease-specific global mortality rates among children aged <5 years by reviewing the results from studies with the best estimates on causes of deaths in children aged 0-59 months. The estimated measles-related mortality among children aged <5 years worldwide decreased from 872,000 deaths in 1990 to 556,000 in 2001 (36% reduction) and to 118,000 in 2008 (86% reduction). All-cause mortality in this age group decreased from >12 million in 1990 to 10.6 million in 2001 (13% reduction) and to 8.8 million in 2008 (28% reduction). Measles accounted for about 7% of deaths in this age group in 1990 and 1% in 2008, equal to 23% of the global reduction in all-cause mortality in this age group from 1990 to 2008. Aggressive efforts to prevent measles have led to this remarkable reduction in measles deaths. The current funding gap and insufficient political commitment for measles control jeopardizes these achievements and presents a substantial risk to achieving MDG4. © The Author 2011. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved.

Building Low Carbon Cities: Framework to Design and Evaluate Alternative Technologies and Policies for Land Use Planning

NASA Astrophysics Data System (ADS)

Hashimoto, S.; Hamano, H.; Fujita, T.; Hori, H.

2008-12-01

Annex I parties of the Kyoto Protocol are facing even greater pressures to fulfill their commitment for GHG reduction as they enter the first commitment period of the Kyoto Protocol 2008-2012. In Japanese context, one such challenge is to reduce CO2 emissions from the household and business sectors because CO2 emissions from the both sectors has increased by 12% and 20% respectively since 1990 while the industry has achieved 21% of CO2 emissions reduction. Land use planning, which, either directly or indirectly, controls appropriate uses for land within jurisdictions, might play very important roles to deal with CO2 reductions from the household and business sectors. In this research, aiming at effective reductions of air- conditioning energy consumption and resultant CO2 emissions from the household and business sectors, the framework to design and evaluate land use planning was developed. The design and evaluation processes embraced in this framework consist of GIS database, technology and policy inventory for planning, one- dimensional urban canopy model which evaluate urban climate at neighborhood level and air-conditioning load calculation procedure. The GIS database provides spatial information of target areas such as land use, building use and road networks, which, then, helps design alternative land use plans. The technology and policy inventory includes various planning options ranging from those for land over control to those for building energy control, which, combined with the GIS database, serves for planning process. The urban canopy model derives vertical profiles of local climate, such as temperature and humidity, using the information of land use, building height and so on, aided by the GIS database. Vertical profiles of the urban climate are then utilized to derive air-conditioning load and associated CO2 emissions for each building located in target areas. The framework developed was applied to the coastal district of Kawasaki, Japan, with an area of 40 square kilometers, for August 2006, to explore effective combinations of technologies and policies for land use planning. Six alternative land use policies were designed, including BaU in which current land use continues, and were, then, evaluated to seek more effective alternatives. Our findings suggested that about 541 MWh power and 204 tons of CO2 emission be saved at maximum by greening building sites, introducing water retentive pavement and installing energy-saving technologies for buildings in an appropriate manner.

Brief communication: Sendai framework for disaster risk reduction - success or warning sign for Paris?

NASA Astrophysics Data System (ADS)

Mysiak, Jaroslav; Surminski, Swenja; Thieken, Annegret; Mechler, Reinhard; Aerts, Jeroen

2016-09-01

In March 2015, a new international blueprint for disaster risk reduction (DRR) was adopted in Sendai, Japan, at the end of the Third UN World Conference on Disaster Risk Reduction (WCDRR, 14-18 March 2015). We review and discuss the agreed commitments and targets, as well as the negotiation leading the Sendai Framework for DRR (SFDRR) and discuss briefly its implication for the later UN-led negotiations on sustainable development goals and climate change.

Putting Green to Work on Your Campus

ERIC Educational Resources Information Center

Ellis, Martha

2008-01-01

Conferences, publications, media, and state mandates provide a plethora of information about community colleges "going green." Indeed, many community college presidents have signed the American College & University Presidents Climate Commitment, a pledge to reduce the carbon footprints of their institutions. But the task is not easy.…

Electrocatalytic Transformation of Carbon Dioxide into Low Carbon Compounds on Conducting Polymers Derived from Multimetallic Porphyrins.

PubMed

Dreyse, Paulina; Honores, Jessica; Quezada, Diego; Isaacs, Mauricio

2015-11-01

The electrochemical reduction of carbon dioxide is studied herein by using conducting polymers based on metallotetraruthenated porphyrins (MTRPs). The polymers on glassy carbon electrodes were obtained by electropolymerization processes of the monomeric MTRP. The linear sweep voltammetry technique resulted in polymeric films that showed electrocatalytic activity toward carbon dioxide reduction with an onset potential of -0.70 V. The reduction products obtained were hydrogen, formic acid, formaldehyde, and methanol, with a tendency for a high production of methanol with a maximum value of turnover frequency equal to 15.07 when using a zinc(II) polymeric surface. Studies of the morphology (AFM) and electrochemical impedance spectroscopy results provide an adequate background to explain that the electrochemical reduction is governed by the roughness of the polymer, for which the possible mechanism involves a series of one-electron reduction reactions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ribosome Levels Selectively Regulate Translation and Lineage Commitment in Human Hematopoiesis.

PubMed

Khajuria, Rajiv K; Munschauer, Mathias; Ulirsch, Jacob C; Fiorini, Claudia; Ludwig, Leif S; McFarland, Sean K; Abdulhay, Nour J; Specht, Harrison; Keshishian, Hasmik; Mani, D R; Jovanovic, Marko; Ellis, Steven R; Fulco, Charles P; Engreitz, Jesse M; Schütz, Sabina; Lian, John; Gripp, Karen W; Weinberg, Olga K; Pinkus, Geraldine S; Gehrke, Lee; Regev, Aviv; Lander, Eric S; Gazda, Hanna T; Lee, Winston Y; Panse, Vikram G; Carr, Steven A; Sankaran, Vijay G

2018-03-22

Blood cell formation is classically thought to occur through a hierarchical differentiation process, although recent studies have shown that lineage commitment may occur earlier in hematopoietic stem and progenitor cells (HSPCs). The relevance to human blood diseases and the underlying regulation of these refined models remain poorly understood. By studying a genetic blood disorder, Diamond-Blackfan anemia (DBA), where the majority of mutations affect ribosomal proteins and the erythroid lineage is selectively perturbed, we are able to gain mechanistic insight into how lineage commitment is programmed normally and disrupted in disease. We show that in DBA, the pool of available ribosomes is limited, while ribosome composition remains constant. Surprisingly, this global reduction in ribosome levels more profoundly alters translation of a select subset of transcripts. We show how the reduced translation of select transcripts in HSPCs can impair erythroid lineage commitment, illuminating a regulatory role for ribosome levels in cellular differentiation. Copyright © 2018 Elsevier Inc. All rights reserved.

Electrochemical reduction of CO2 to CO over Zn in propylene carbonate/tetrabutylammonium perchlorate

NASA Astrophysics Data System (ADS)

Shen, Feng-xia; Shi, Jin; Chen, Tian-you; Shi, Feng; Li, Qing-yuan; Zhen, Jian-zheng; Li, Yun-fei; Dai, Yong-nian; Yang, Bin; Qu, Tao

2018-02-01

Developing low cost and high efficient electrode for carbon dioxide (CO2) reduction in organic media is essential for practical application. Zn is a cheap metal and has high catalytic effects on CO2 reduction to carbon monoxide (CO) in aqueous solution. However, little attention has been given to investigate the performance of Zn in organic media for CO2 reduction. In present work, we have conducted CO2 reduction in propylene carbonate/tetrabutylammonium perchlorate on Zn due to that propylene carbonate is a widely used industrial absorber, and tetrabutylammonium perchlorate is a commonly used organic supporting electrolyte. In addition, because electrochemical reduction of CO2 to CO naturally produces H2O, we have discussed water effects on CO2 reduction in propylene carbonate/tetrabutylammonium perchlorate+6.8 wt % H2O. Our experiment results reveal that the faradaic efficiency for CO formation reaches to 83%, and the current density remains stable at 6.72 mA/cm2 at voltage -2.3 V for 4 h. Interestingly, Zn presents higher catalytic activity than Ag, and slightly lower than Au. X-ray photoelectron spectroscopy results confirm that no poisonous species is formed and absorbed on the cathode, which is an important advantage in practical application.

A Biochemical Magic Frequency

NASA Technical Reports Server (NTRS)

Weber, Arthur L.

1993-01-01

Life is composed principally of four classes of biomolecules - protein, nucleic acid, polysaccharide and lipid. Using 1) estimates of the reducing equivalents (electron pairs) needed to synthesize these biomolecules from carbon dioxide, and 2) measurements of the molecular composition of different organisms, we calculated the average number of electron pairs required for the reduction of carbon dioxide to biological carbon (electron pairs/carbon atom). These calculations showed that the carbon of the Earths biosphere is at the reduction level of formaldehyde that requires 2 electron pairs/carbon atom to be synthesized from carbon dioxide. This was also the reduction level of carbon of individual organisms, except for those that stored large amounts of fuel as lipid. Since this chemical property of life is easily discovered and probably universal, it's most likely known by other intelligent life in the universe. It could be the one thing we know about other carbon-based life in the universe, and the one thing that other intelligent life knows about us. We believe this common knowledge that formaldehyde represents the reduction level of life's carbon could lead to the selection of the 72.83814 GHz line of the 0,0,0,1,0,1 ground-state rotational transition of formaldehyde as a frequency for interstellar communication.

Carbon Dioxide Emissions Effects of Grid-Scale Electricity Storage in a Decarbonizing Power System

DOE PAGES

Craig, Michael T.; Jaramillo, Paulina; Hodge, Bri-Mathias

2018-01-03

While grid-scale electricity storage (hereafter 'storage') could be crucial for deeply decarbonizing the electric power system, it would increase carbon dioxide (CO 2) emissions in current systems across the United States. To better understand how storage transitions from increasing to decreasing system CO 2 emissions, we quantify the effect of storage on operational CO 2 emissions as a power system decarbonizes under a moderate and strong CO 2 emission reduction target through 2045. Under each target, we compare the effect of storage on CO 2 emissions when storage participates in only energy, only reserve, and energy and reserve markets. Wemore » conduct our study in the Electricity Reliability Council of Texas (ERCOT) system and use a capacity expansion model to forecast generator fleet changes and a unit commitment and economic dispatch model to quantify system CO 2 emissions with and without storage. We find that storage would increase CO 2 emissions in the current ERCOT system, but would decrease CO 2 emissions in 2025 through 2045 under both decarbonization targets. Storage reduces CO 2 emissions primarily by enabling gas-fired generation to displace coal-fired generation, but also by reducing wind and solar curtailment. We further find that the market in which storage participates drives large differences in the magnitude, but not the direction, of the effect of storage on CO 2 emissions.« less

Carbon Dioxide Emissions Effects of Grid-Scale Electricity Storage in a Decarbonizing Power System

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

Craig, Michael T.; Jaramillo, Paulina; Hodge, Bri-Mathias

While grid-scale electricity storage (hereafter 'storage') could be crucial for deeply decarbonizing the electric power system, it would increase carbon dioxide (CO 2) emissions in current systems across the United States. To better understand how storage transitions from increasing to decreasing system CO 2 emissions, we quantify the effect of storage on operational CO 2 emissions as a power system decarbonizes under a moderate and strong CO 2 emission reduction target through 2045. Under each target, we compare the effect of storage on CO 2 emissions when storage participates in only energy, only reserve, and energy and reserve markets. Wemore » conduct our study in the Electricity Reliability Council of Texas (ERCOT) system and use a capacity expansion model to forecast generator fleet changes and a unit commitment and economic dispatch model to quantify system CO 2 emissions with and without storage. We find that storage would increase CO 2 emissions in the current ERCOT system, but would decrease CO 2 emissions in 2025 through 2045 under both decarbonization targets. Storage reduces CO 2 emissions primarily by enabling gas-fired generation to displace coal-fired generation, but also by reducing wind and solar curtailment. We further find that the market in which storage participates drives large differences in the magnitude, but not the direction, of the effect of storage on CO 2 emissions.« less

Carbon dioxide emissions effects of grid-scale electricity storage in a decarbonizing power system

NASA Astrophysics Data System (ADS)

Craig, Michael T.; Jaramillo, Paulina; Hodge, Bri-Mathias

2018-01-01

While grid-scale electricity storage (hereafter ‘storage’) could be crucial for deeply decarbonizing the electric power system, it would increase carbon dioxide (CO2) emissions in current systems across the United States. To better understand how storage transitions from increasing to decreasing system CO2 emissions, we quantify the effect of storage on operational CO2 emissions as a power system decarbonizes under a moderate and strong CO2 emission reduction target through 2045. Under each target, we compare the effect of storage on CO2 emissions when storage participates in only energy, only reserve, and energy and reserve markets. We conduct our study in the Electricity Reliability Council of Texas (ERCOT) system and use a capacity expansion model to forecast generator fleet changes and a unit commitment and economic dispatch model to quantify system CO2 emissions with and without storage. We find that storage would increase CO2 emissions in the current ERCOT system, but would decrease CO2 emissions in 2025 through 2045 under both decarbonization targets. Storage reduces CO2 emissions primarily by enabling gas-fired generation to displace coal-fired generation, but also by reducing wind and solar curtailment. We further find that the market in which storage participates drives large differences in the magnitude, but not the direction, of the effect of storage on CO2 emissions.

[Analysis of carbon balance and study on mechanism in anoxic-oxic-settling-anaerobic sludge reduction process].

PubMed

Zhai, Xiao-Min; Gao, Xu; Zhang, Man-Man; Jia, Li; Guo, Jin-Song

2012-07-01

In order to deeply explore the mechanism of sludge reduction in OSA system, carbon balance was performed in an anoxic-oxic-settling-anaerobic (A + OSA) system and a reference AO system to investigate effects of inserting a sludge holding tank in sludge cycle line on the sludge reduction process. Meanwhile, carbon mass change in each reaction unit was identified in terms of solid, liquid and gas phases. The causes of excess sludge reduction in A + OSA system were deduced. The carbon balance results show that when the hydraulic retention time in the sludge holding tank is 7.14 h, carbon percent in solid phase of the sludge reduction system is nearly 50% higher than that of the reference system, supporting the consequence that sludge reduction rate of 49.98% had been achieved. The insertion of a sludge holding tank in the sludge return circuit can be effective in sludge reduction. Carbon changes in each unit reveal that the amount of carbon consumed for biosynthesis in the anoxic and oxic tanks (main reaction zone) of the sludge reduction system is higher than in that of the reference system. Sludge decay is observed in the sludge holding tank. Furthermore, CH4 released from the sludge holding tank is significantly higher than that from the main reaction zone. The DGGE profiles show that there are hydrolytic-fermentative bacteria in the sludge holding tank related to sludge decay. The excess sludge reduction in the A + OSA system could be a result of the combination of sludge decay in the sludge holding tank and sludge compensatory growth in the main reaction cell.

Long-term climate change commitment and reversibility: An EMIC intercomparison

NASA Astrophysics Data System (ADS)

Zickfeld, K.; Eby, M.; Weaver, A. J.

2012-12-01

This paper summarizes the results of an intercomparison project with Earth System Models of Intermediate Complexity (EMICs) undertaken in support of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). The focus is on long-term climate projections designed to: (i) quantify the climate change "commitment" of a range of radiative forcing trajectories, and (ii) explore the extent to which climate change is reversible if atmospheric CO2 is left to evolve freely or is artificially restored to pre-industrial levels. All commitment simulations follow the four Representative Concentration Pathways (RCPs) and their extensions to 2300. Most EMICs simulate significant surface air temperature and thermosteric sea level rise commitment following stabilization of the atmospheric composition at year-2300 levels. The additional warming by the year 3000 is 0.0-0.6 °C for RCP4.5 and 0.0-1.2 °C for RCP8.5, and the additional sea level rise is 0.1-1.0 m for RCP4.5 and 0.4-2.6 m for RCP8.5. Elimination of anthropogenic CO2 emissions results in constant or slightly decreasing surface air temperature in all EMICs. Thermosteric sea level rise continues after elimination of anthropogenic CO2 emissions, with additional sea level rise between 2300 and 3000 of 0.0-0.5 m for RCP4.5 and 0.2-2.4 m for RCP8.5. The largest warming and sea level rise commitment are simulated for the case with constant year-2300 CO2 emissions. Restoration of atmospheric CO2 from RCP to pre-industrial levels over 100-1000 years does not result in the simultaneous return to pre-industrial climate conditions, as surface air temperature and sea level rise exhibit a substantial time lag relative to atmospheric CO2, and requires large artificial removal of CO2 from the atmosphere. Results of the climate change commitment and reversibility simulations differ widely among EMICs, both in the physical and biogeochemical response. Particularly large differences are identified in the response of the terrestrial carbon cycle to atmospheric CO2 and climate, highlighting the need for improved understanding and representation of land carbon cycle processes in Earth System models.

Optimisation of entrapped activated carbon conditions to remove coloured compounds from winery wastewaters.

PubMed

Devesa-Rey, R; Bustos, G; Cruz, J M; Moldes, A B

2011-06-01

The objective of this work was to study the entrapped conditions of activated carbon in calcium-alginate beads for the clarification of winery wastewaters. An incomplete 3(3) factorial design was carried out to study the efficiency of activated carbon (0.5-2%); sodium alginate (1-5%); and calcium chloride (0.050-0.900 M), on the following dependent variables: colour reduction at 280, 465, 530 and 665 nm. The activated carbon and calcium chloride were the most influential variables in the colour reduction. Nearly 100% colour reductions were found for the wavelengths assayed when employing 2% of activated carbon, 5% of sodium alginate and intermediate concentrations of calcium chloride (0.475 M). Instead, other conditions like, 2% of activated carbon, 4% of sodium alginate and 0.580 M of calcium chloride can also give absorbance reductions close to 100%. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Effect of the Agricultural Carbon Sequestration and Agrochemical Reduction on the Regional Water Environment Quality

NASA Astrophysics Data System (ADS)

Leyi, Wang; Baoli, Zhang; Xin, Li; Juan, Du

2018-05-01

This paper analysed the impact of the agricultural carbon reduction and emission reduction measures implementation on the environmental quality of surface water and groundwater in winter and summer in Henan and Anhui Province project areas by using entropy weight fuzzy matter element analysis method. The result showed that the reduction in the application of chemical fertilizers and pesticides had a certain impact on the improvement of the water environment by using agricultural carbon sequestration technologies.

[Effects of nurses' social capital on turnover intention: focused on the mediating effects organizational commitment and organizational cynicism].

PubMed

Han, Jeongwon; Woo, Heeyoung; Ju, Eunsil; Lim, Sohee; Han, Sangsook

2013-08-01

The purpose of this study was to investigate the casual relationship between nurses' social capital and turnover intention and to verify the goodness of fit between a hypothetical model and actual data in order to suggest the best model. This survey was conducted with 315 nurses working in general hospitals in Seoul. Data were collected from December 1 to December 30, 2011, and analyzed using SPSS Windows 18.0 and AMOS 16.0. Nurses' social capital was found to have a direct effect on reducting organization cynicism and increasing organizational commitment. Nurses' organizational cynicism and organizational commitment were found to have a direct effect on turnover intention, but social capital did not have a direct effect on turnover intention. However, social capital had a partial and indirect effect on turnover intention through mediating organizational cynicism and organizational commitment. Results of this study indicate that nurse managers should put increased effort in reducing nurses' organizational cynicism and improving their organizational commitment, two contrary parameters. At the same time managers need to develop plans to establish social capital more efficiently so that nurses have lower turnover intention.

Low Energy Schools in Ireland

ERIC Educational Resources Information Center

Heffernan, Martin

2004-01-01

Out of a commitment to reducing carbon dioxide emissions, Ireland's Department of Education and Science has designed and constructed two low energy schools, in Tullamore, County Offaly, and Raheen, County Laois. With energy use in buildings responsible for approximately 55% of the CO[subscript 2] released into the atmosphere and a major…

Carbon Neutrality and the Use of Offsets

ERIC Educational Resources Information Center

Ney, Richard A.; Purman, Judith R.

2009-01-01

Many organizations, including colleges and universities, are moving to address the threat of climate change by reducing greenhouse gas (GHG) emissions from their operations. For example, the rapid growth of participation in the Presidents Climate Commitment (PCC) now means that more than 600 colleges and universities have pledged to develop plans…

The Educational Facilities Professional's Practical Guide to Reducing the Campus Carbon Footprint

ERIC Educational Resources Information Center

Hignite, Karla

2009-01-01

As more institutions respond to the American College & University Presidents Climate Commitment, or are otherwise responsible for campus environmental stewardship, this implementation guide gives educational facilities professionals a practical framework for moving forward in their unique role within this process. The intent is to help facilities…

Does smoking cannabis affect work commitment?

PubMed

Hyggen, Christer

2012-07-01

  This study aimed to examine the associations between cannabis use and work commitment.   We used a 25-year panel survey initiated in 1985 with follow-ups in 1987, 1989, 1993, 2003 and 2010. Registered data from a range of public registers were matched with individual responses for the entire period.   The panel survey was a nation-wide study set in Norway.   A total of 1997 respondents born between 1965 and 1968 were included in the panel.   Work involvement scale (WIS) was used to assess work commitment. Involvement with cannabis was based on self-reported smoking of cannabis within the last 12 months and exposure to cannabis through friends. This information was categorized into 'abstaining', 'exposed', 'experimented' and 'involved'. Control measures included socio-economic background, mental health (HSCL-10), education, work satisfaction, unemployment, receipt of social assistance, consumption of alcohol, alcohol-related problems and use of other illicit drugs.   The level of work commitment was associated with involvement with cannabis. In 1993, when the respondents were in their mid-20s, those who were involved or had experimented with cannabis displayed lower levels of work commitment than those who were abstaining or merely exposed to cannabis through friends (P < 0.05). Work commitment among those who experimented with cannabis converged towards the levels reported by abstainers and the exposed as they grew older, whereas those involved reported decreasing work commitment into adulthood (P < 0.001). Using linear regression models for panel data, an association with continued use of cannabis across the life-course and a lowering of work commitment was established. Results remained significant even when controlling for a range of other factors known to be related to work commitment, such as socio-economic background, education, labour market experiences, mental health and family characteristics (P < 0.05).   In Norway the use of cannabis is associated with a reduction in work commitment among adults. © 2012 The Author, Addiction © 2012 Society for the Study of Addiction.

REPEATED REDUCTIVE AND OXIDATIVE TREATMENTS ON GRANULAR ACTIVATED CARBON

EPA Science Inventory

Fenton oxidation and Fenton oxidation preceded by reduction solutions were applied to granular activated carbon (GAC) to chemically regenerate the adsorbent. No adsorbate was present on the GAC so physicochemical effects from chemically aggressive regeneration of the carbon coul...

Forest wildfire, fuel reduction treatments, and landscape carbon stocks: a sensitivity analysis

Treesearch

John L. Campbell; Alan A. Ager

2013-01-01

Fuel reduction treatments prescribed in fire-suppressed forests of western North America pose an apparent paradox with respect to terrestrial carbon management. Such treatments have the immediate effect of reducing forest carbon stocks but likely reduce future carbon losses through the combustion and mortality caused by high-severity wildfires. Assessing the long-term...

Evaluating the CO 2 emissions reduction potential and cost of power sector re-dispatch

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

Steinberg, Daniel C.; Bielen, David A.; Townsend, Aaron

Prior studies of the U.S. electricity sector have recognized the potential to reduce carbon dioxide (CO2) emissions by substituting generation from coal-fired units with generation from under-utilized and lower-emitting natural gas-fired units; in fact, this type of 're-dispatch' was invoked as one of the three building blocks used to set the emissions targets under the Environmental Protection Agency's Clean Power Plan. Despite the existence of surplus natural gas capacity in the U.S., power system operational constraints not often considered in power sector policy analyses, such as transmission congestion, generator ramping constraints, minimum generation constraints, planned and unplanned generator outages, andmore » ancillary service requirements, could limit the potential and increase the cost of coal-to-gas re-dispatch. Using a highly detailed power system unit commitment and dispatch model, we estimate the maximum potential for re-dispatch in the Eastern Interconnection, which accounts for the majority of coal capacity and generation in the U.S. Under our reference assumptions, we find that maximizing coal-to-gas re-dispatch yields emissions reductions of 230 million metric tons (Mt), or 13% of power sector emissions in the Eastern Interconnection, with a corresponding average abatement cost of $15-$44 per metric ton of CO2, depending on the assumed supply elasticity of natural gas.« less

An integrated framework for evaluating the effects of deforestation on ecosystem services

NASA Astrophysics Data System (ADS)

Song, X. P.; Huang, C.; Townshend, J. R.

2014-03-01

Deforestation often results in massive carbon emissions and loss of ecosystem services. The objective of this paper is to develop an integrated approach to quantitatively derive changes in forest carbon stock and changes in the economic value of forest carbon due to deforestation. Combining the best available remote sensing and socioeconomic datasets, this approach establishes a comprehensive baseline of deforestation in terms of area, carbon and monetary value change. We applied this end-to-end evaluation method in the Brazilian state of Rondonia to assess the ecological and economic effects of its recent deforestation from 2000 to 2005. Our results suggest that deforestation occurred at an average rate of 2834 km2/yr during the study period, leading to 31 TgC/yr "committed carbon emissions" from deforestation. Coupling with the social cost of carbon at 23/tC and a market discount rate at 7%, this translates to 622 million U.S. dollars/yr loss in the economic value of forest carbon.

Projections of Ocean Acidification Under the U.N. Framework Convention of Climate Change Using a Reduced-Form Climate Carbon-Cycle Model

NASA Astrophysics Data System (ADS)

Hartin, C.

2016-02-01

Ocean chemistry is quickly changing in response to continued anthropogenic emissions of carbon to the atmosphere. Mean surface ocean pH has already decreased by 0.1 units relative to the preindustrial era. We use an open-source, simple climate and carbon cycle model ("Hector") to investigate future changes in ocean acidification (pH and calcium carbonate saturations) under the climate agreement from the United Nations Convention on Climate Change Conference (UNFCCC) of Parties in Paris 2015 (COP 21). Hector is a reduced-form, very fast-executing model that can emulate the global mean climate of the CMIP5 models, as well as the inorganic carbon cycle in the upper ocean, allowing us to investigate future changes in ocean acidification. We ran Hector under three different emissions trajectories, using a sensitivity analysis approach to quantify model uncertainty and capture a range of possible ocean acidification changes. The first trajectory is a business-as-usual scenario comparable to a Representative Concentration Pathway (RCP) 8.5, the second a scenario with the COP 21 commitments enacted, and the third an idealized scenario keeping global temperature change to 2°C, comparable to a RCP 2.6. Preliminary results suggest that under the COP 21 agreements ocean pH at 2100 will decrease by 0.2 units and surface saturations of aragonite (calcite) will decrease by 0.9 (1.4) units relative to 1850. Under the COP 21 agreement the world's oceans will be committed to a degree of ocean acidification, however, these changes may be within the range of natural variability evident in some paleo records.

Synthesis of reduced carbon nitride at the reduction by hydroquinone of water-soluble carbon nitride oxide (g-C{sub 3}N{sub 4})O

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

Kharlamov, Alexey; Bondarenko, Marina, E-mail: mebondarenko@ukr.net; Kharlamova, Ganna

For the first time at the reduction by hydroquinone of water-soluble carbon nitride oxide (g-C{sub 3}N{sub 4})O reduced carbon nitride (or reduced multi-layer azagraphene) is obtained. It is differed from usually synthesized carbon nitride by a significantly large (on 0.09 nm) interplanar distance is. At the same time, the chemical bonds between atoms in a heteroatomic plane of reduced carbon nitride correspond to the bonds in a synthesized g-C{sub 3}N{sub 4}. The samples of water-soluble carbon nitride oxide were synthesized under the special reactionary conditions of a pyrolysis of melamine and urea. We believe that reduced carbon nitride consists ofmore » weakly connected carbon-nitrogen monosheets (azagraphene sheets) as well as reduced (from graphene oxide) graphene contains weakly connected graphene sheets. - Graphical abstract: XRD pattern and schematic atomic model of one layer of reduced carbon nitride, carbon nitride oxide and synthesized carbon nitride. For the first time at the reduction by hydroquinone of the water-soluble carbon nitride oxide (g-C{sub 3}N{sub 4})O is obtained the reduced carbon nitride (or reduced multi-layer azagraphene). Display Omitted - Highlights: • First the reduced carbon nitride (RCN) at the reduction of the carbon nitride oxide was obtained. • Water-soluble carbon nitride oxide was reduced by hydroquinone. • The chemical bonds in a heteroatomic plane of RCN correspond to the bonds in a synthesized g-C{sub 3}N{sub 4}. • Reduced carbon nitride consists of poorly connected heteroatomic azagraphene layers.« less

Characterization of nickel laterite reduction from Pomalaa, Sulawesi Tenggara

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

Rhamdani, Ahmad Rizky; Petrus, Himawan T. B. M., E-mail: bayu.petrus@ugm.ac.id; Fahrurrozi, Moh.

2015-12-29

The effect of using different reductors in the reduction process of nickel laterite was investigated. In this work, the author conducted the reduction of nickel laterite ores by anthracite coal, lamtoro charcoal, and carbon raiser, in air and CO{sub 2} atmosphere, within the temperature ranged from 800°C and 1000°C. The results indicate that at higher temperatures, the reduction reactions proceed more complete. According to the X-ray powder diffraction (XRD) analysis, the type of carbon used greatly influence the rate of the reduction of nickel laterite. The order of reactivity is anthracite coal, lamtoro charcoal, and carbon raiser, respectively. The reductionmore » atmospheric condition also greatly influences the reduction process. The reduction process in CO{sub 2} atmospheric condition gives a lot of significant decrease in hematite and magnetite presence, means that the reduction reactions proceed more complete compared to the reduction process in the air atmospheric condition.« less

Carbothermal Reduction of Quartz and Carbon Pellets at Elevated Temperatures

NASA Astrophysics Data System (ADS)

Li, Fei; Tangstad, Merete; Ringdalen, Eli

2018-06-01

In this study, the carbothermal reduction of pellets composed of quartz and carbon at temperatures between 1898 K and 1948 K (1625 °C and 1675 °C) are investigated. The main product from this reaction is silicon carbide (SiC). The reduction of quartz with carbon black, charcoal, coke, coal, and pre-heated coal in the pellet were compared to investigate the different carbon resources used in silicon production. Charcoal and coke have high SiO reactivity, while carbon black and coal (pre-heated coal) have low SiO reactivity. Charcoal and carbon black show better matching between quartz/carbon reactivity and SiO reactivity, and will lose less SiO gas than coke and pre-heated coal. Coal has a high volatile content and is thus not recommended as a raw material for the pellets.

Evaluation of Contrail Reduction Strategies Based on Environmental and Operational Costs

NASA Technical Reports Server (NTRS)

Chen, Neil Y.; Sridhar, Banavar; Ng, Hok K.; Li, Jinhua

2013-01-01

This paper evaluates a set of contrail reduction strategies based on environmental and operational costs. A linear climate model was first used to convert climate effects of carbon dioxide emissions and aircraft contrails to changes in Absolute Global Temperature Potential, a metric that measures the mean surface temperature change due to aircraft emissions and persistent contrail formations. The concept of social cost of carbon and the carbon auction price from recent California's cap-and-trade system were then used to relate the carbon dioxide emissions and contrail formations to an environmental cost index. The strategy for contrail reduction is based on minimizing contrail formations by altering the aircraft's cruising altitude. The strategy uses a user-defined factor to trade off between contrail reduction and additional fuel burn and carbon dioxide emissions. A higher value of tradeoff factor results in more contrail reduction but also more fuel burn and carbon emissions. The strategy is considered favorable when the net environmental cost benefit exceeds the operational cost. The results show how the net environmental benefit varies with different decision-making time-horizon and different carbon cost. The cost models provide a guidance to select the trade-off factor that will result in the most net environmental benefit.

Will Fire Danger Be Reduced by Using Solar Radiation Management to Limit Global Warming to 1.5 °C Compared to 2.0 °C?

NASA Astrophysics Data System (ADS)

Burton, C.; Betts, R. A.; Jones, C. D.; Williams, K.

2018-04-01

The commitment to limit warming to 1.5 °C as set out in the Paris Agreement is widely regarded as ambitious and challenging. It has been proposed that reaching this target may require a number of actions, which could include some form of carbon removal or Solar Radiation Management in addition to strong emission reductions. Here we assess one theoretical solution using Solar Radiation Management to limit global mean warming to 1.5 °C above preindustrial temperatures and use the McArthur fire danger index to evaluate the change in fire danger. The results show that globally fire danger is reduced in most areas when temperatures are limited to 1.5 °C compared to 2.0 °C. The number of days where fire danger is "high" or above is reduced by up to 30 days/year on average, although there are regional variations. In certain regions, fire danger is increased, experiencing 31 more days above "high" fire danger.

Neurophysiological mechanisms in acceptance and commitment therapy in opioid-addicted patients with chronic pain.

PubMed

Smallwood, Rachel F; Potter, Jennifer S; Robin, Donald A

2016-04-30

Acceptance and Commitment Therapy (ACT) has been effectively utilized to treat both chronic pain and substance use disorder independently. Given these results and the vital need to treat the comorbidity of the two disorders, a pilot ACT treatment was implemented in individuals with comorbid chronic pain and opioid addiction. This pilot study supported using neurophysiology to characterize treatment effects and revealed that, following ACT, participants with this comorbidity exhibited reductions in brain activation due to painful stimulus and in connectivity at rest. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Understanding trends in electrochemical carbon dioxide reduction rates

DOE PAGES

Liu, Xinyan; Xiao, Jianping; Peng, Hongjie; ...

2017-05-22

Electrochemical carbon dioxide reduction to fuels presents one of the great challenges in chemistry. Herein we present an understanding of trends in electrocatalytic activity for carbon dioxide reduction over different metal catalysts that rationalize a number of experimental observations including the selectivity with respect to the competing hydrogen evolution reaction. We also identify two design criteria for more active catalysts. The understanding is based on density functional theory calculations of activation energies for electrochemical carbon monoxide reduction as a basis for an electrochemical kinetic model of the process. Furthermore, we develop scaling relations relating transition state energies to the carbonmore » monoxide adsorption energy and determine the optimal value of this descriptor to be very close to that of copper.« less

Understanding trends in electrochemical carbon dioxide reduction rates

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

Liu, Xinyan; Xiao, Jianping; Peng, Hongjie

Electrochemical carbon dioxide reduction to fuels presents one of the great challenges in chemistry. Herein we present an understanding of trends in electrocatalytic activity for carbon dioxide reduction over different metal catalysts that rationalize a number of experimental observations including the selectivity with respect to the competing hydrogen evolution reaction. We also identify two design criteria for more active catalysts. The understanding is based on density functional theory calculations of activation energies for electrochemical carbon monoxide reduction as a basis for an electrochemical kinetic model of the process. Furthermore, we develop scaling relations relating transition state energies to the carbonmore » monoxide adsorption energy and determine the optimal value of this descriptor to be very close to that of copper.« less

Density Functional Theory Research into the Reduction Mechanism for the Solvent/Additive in a Sodium-Ion Battery.

PubMed

Liu, Qi; Mu, Daobin; Wu, Borong; Wang, Lei; Gai, Liang; Wu, Feng

2017-02-22

The solid-electrolyte interface (SEI) film in a sodium-ion battery is closely related to capacity fading and cycling stability of the battery. However, there are few studies on the SEI film of sodium-ion batteries and the mechanism of SEI film formation is unclear. The mechanism for the reduction of ethylene carbonate (EC), propylene carbonate (PC), vinylene carbonate (VC), ethylene sulfite (ES), 1,3-propylene sulfite (PS), and fluorinated ethylene carbonate (FEC) is studied by DFT. The reaction activation energies, Gibbs free energies, enthalpies, and structures of the transition states are calculated. It is indicated that VC, ES, and PS additives in the electrolyte are all easier to form organic components in the anode SEI film by one-electron reduction. The priority of one-electron reduction to produce organic SEI components is in the order of VC>PC>EC; two-electron reduction to produce the inorganic Na 2 CO 3 component is different and follows the order of EC>PC>VC. Two-electron reduction for sulfites ES and PS to form inorganic Na 2 SO 3 is harder than that of carbonate ester reduction. It is also suggested that the one- and two-electron reductive decomposition pathway for FEC is more feasible to produce inorganic NaF components. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

U.S. Draft Domestic Action Plan for Lake Erie

EPA Pesticide Factsheets

In 2016, in response to the 2012 Great Lakes Water Quality Agreement commitments, Canada and the U.S. adopted phosphorus reduction targets for Lake Erie. Each country is developing domestic action plans which outline strategies for meeting the new targets.

Microbiology of Shell Egg Production in the United States

USDA-ARS?s Scientific Manuscript database

A significant proportion of human illnesses caused by Salmonella are linked to the consumption of contaminated eggs. Substantial government and industry resources have been committed to comprehensive Salmonella testing and risk reduction programs for commercial egg-laying flocks. The implementation ...

Revealing the Origin of Activity in Nitrogen-Doped Nanocarbons towards Electrocatalytic Reduction of Carbon Dioxide.

PubMed

Xu, Junyuan; Kan, Yuhe; Huang, Rui; Zhang, Bingsen; Wang, Bolun; Wu, Kuang-Hsu; Lin, Yangming; Sun, Xiaoyan; Li, Qingfeng; Centi, Gabriele; Su, Dangsheng

2016-05-23

Carbon nanotubes (CNTs) are functionalized with nitrogen atoms for reduction of carbon dioxide (CO2 ). The investigation explores the origin of the catalyst's activity and the role of nitrogen chemical states therein. The catalysts show excellent performances, with about 90 % current efficiency for CO formation and stability over 60 hours. The Tafel analyses and density functional theory calculations suggest that the reduction of CO2 proceeds through an initial rate-determining transfer of one electron to CO2 , which leads to the formation of carbon dioxide radical anion (CO2 (.-) ). The initial reduction barrier is too high on pristine CNTs, resulting in a very high overpotentials at which the hydrogen evolution reaction dominates over CO2 reduction. The doped nitrogen atoms stabilize the radical anion, thereby lowering the initial reduction barrier and improving the intrinsic activity. The most efficient nitrogen chemical state for this reaction is quaternary nitrogen, followed by pyridinic and pyrrolic nitrogen. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Microscopic Study of Carbon Surfaces Interacting with High Carbon Ferromanganese Slag

NASA Astrophysics Data System (ADS)

Safarian, Jafar; Kolbeinsen, Leiv

2015-02-01

The interaction of carbon materials with molten slags occurs in many pyro-metallurgical processes. In the production of high carbon ferromanganese in submerged arc furnace, the carbothermic reduction of MnO-containing silicate slags yields the metal product. In order to study the interaction of carbon with MnO-containing slags, sessile drop wettability technique is employed in this study to reduce MnO from a molten slag drop by carbon substrates. The interfacial area on the carbon substrate before and after reaction with slag is studied by scanning electron microscope. It is indicated that no Mn metal particles are found at the interface through the reduction of the MnO slag. Moreover, the reduction of MnO occurs through the contribution of Boudouard reaction and it causes carbon consumption in particular active sites at the interface, which generate carbon degradation and open pore growth at the interface. It is shown that the slag is fragmented to many micro-droplets at the reaction interface, potentially due to the effect on the interfacial energies of a provisional liquid Mn thin film. The rapid reduction of these slag micro-droplets affects the carbon surface with making deep micro-pores. A mechanism for the formation of slag micro-droplets is proposed, which is based on the formation of provisional micro thin films of liquid Mn at the interface.

Integrated Modeling and Assessment of Climate Change Mitigation in North America: Lessons learned from Mexico

NASA Astrophysics Data System (ADS)

Olguin-Alvarez, M. I.; Kurz, W. A.; Wayson, C.; Birdsey, R.; Richardson, K.; Angeles, G.; Vargas, B.; Corral, J.; Magnan, M.; Fellows, M.; Morken, S.; Maldonado, V.; Mascorro, V.; Meneses, C.; Galicia, G.; Serrano, E.

2016-12-01

The Government of Mexico has recently designed a system of measurement, reporting and verification (MRV) to account for the emissions and removals of greenhouse gases (GHG) associated with the country's forest sector. This system reports national-scale GHG emissions based on the "stock-difference" approach combining information from two sets of measurements from the national forest inventory and remote sensing data. However, consistent with the commitments made by the country to the United Nations Framework Convention on Climate Change (UNFCCC), the MRV system must strive to reduce, as far as practicable, the uncertainties associated with national estimates on GHG fluxes. Since 2012, the Mexican government through its National Forestry Commission, with support from the North America Commission of Environmental Cooperation, the Forest Services of Canada and USA, the SilvaCarbon Program and research institutes in Mexico, has made progress towards the use of carbon dynamics models ("gain-loss" approach) to reduce uncertainty of the GHG estimates in strategic landscapes. In Mexico, most of the forests are under social tenure where management includes a wide array of activities (e.g. selective harvesting, firewood collection). Altering these diverse management activities (REDD+ strategies as well as harvested wood products), can augment their mitigation potential. Here we present the main steps conducted to compile and integrate information from forest inventories, remote sensing, disturbance data and ecosystem carbon transfers to generate inputs required to calibrate these models and validate their outputs. The analyses are supported by the use of the CBM-CFS3 model with the appropriate modification of the model parameters and input data according to the 2006 guidelines of the Intergovernmental Panel on Climate Change (IPCC) for preparing Tier 3-GHG inventories. The ultimate goal of this tri-national effort is to show how the data and tools developed for carbon assessment in strategic landscapes in North America can help estimate the impact of several mitigation options consistent with national goals of GHG emission reductions.

Kinetic study of the carbothermic synthesis of uranium monocarbide microspheres

NASA Astrophysics Data System (ADS)

Mukerjee, S. K.; Dehadraya, J. V.; Vaidya, V. N.; Sood, D. D.

1990-06-01

Uranium monocarbide microspheres were synthesized by carbothermic reduction of porous uranium oxide microspheres with uniformly dispersed carbon black. Kinetics of the reduction was studied under vacuum and flowing inert gas from 1250 to 1550° C. The carbon monoxide gas concentration in the effluent stream during reduction was used to determine the rate of carbide formation. Under vacuum, reduction was found to be controlled by reaction at the reactant-product interface whereas under flowing gas conditions, the diffusion of carbon monoxide gas through the carbide layer was the rate controlling process. The activation energy was 335.1 ± 8.6 and 363.7 ± 7.6 kJ/mol for reduction under vacuum and flowing gas, respectively.

An analysis of the feasibility of carbon management policies as a mechanism to influence water conservation using optimization methods.

PubMed

Wright, Andrew; Hudson, Darren

2014-10-01

Studies of how carbon reduction policies would affect agricultural production have found that there is a connection between carbon emissions and irrigation. Using county level data we develop an optimization model that accounts for the gross carbon emitted during the production process to evaluate how carbon reducing policies applied to agriculture would affect the choices of what to plant and how much to irrigate by producers on the Texas High Plains. Carbon emissions were calculated using carbon equivalent (CE) calculations developed by researchers at the University of Arkansas. Carbon reduction was achieved in the model through a constraint, a tax, or a subsidy. Reducing carbon emissions by 15% resulted in a significant reduction in the amount of water applied to a crop; however, planted acreage changed very little due to a lack of feasible alternative crops. The results show that applying carbon restrictions to agriculture may have important implications for production choices in areas that depend on groundwater resources for agricultural production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Investigation of reductive dechlorination supported by natural organic carbon

USGS Publications Warehouse

Rectanus, H.V.; Widdowson, M.A.; Chapelle, F.H.; Kelly, C.A.; Novak, J.T.

2007-01-01

Because remediation timeframes using monitored natural attenuation may span decades or even centuries at chlorinated solvent sites, new approaches are needed to assess the long-term sustainability of reductive dechlorination in ground water systems. In this study, extraction procedures were used to investigate the mass of indigenous organic carbon in aquifer sediment, and experiments were conducted to determine if the extracted carbon could support reductive dechlorination of chloroethenes. Aquifer sediment cores were collected from a site without an anthropogenic source of organic carbon where organic carbon varied from 0.02% to 0.12%. Single extraction results showed that 1% to 28% of sediment-associated organic carbon and 2% to 36% of the soft carbon were removed depending on nature and concentration of the extracting solution (Nanopure water; 0.1%, 0.5%, and 1.0% sodium pyrophosphate; and 0.5 N sodium hydroxide). Soft carbon is defined as organic carbon oxidized with potassium persulfate and is assumed to serve as a source of biodegradable carbon within the aquifer. Biodegradability studies demonstrated that 20% to 40% of extracted organic carbon was biodegraded aerobically and anaerobically by soil microorganisms in relatively brief tests (45 d). A five-step extraction procedure consisting of 0.1% pyrophosphate and base solutions was investigated to quantify bioavailable organic carbon. Using the extracted carbon as the sole electron donor source, tetrachloroethene was transformed to cis-1,2- dichloroethene and vinyl chloride in anaerobic enrichment culture experiments. Hydrogen gas was produced at levels necessary to sustain reductive dechlorination (>1 nM). ?? 2007 National Ground Water Association.

Greenhouse Gas Mitigation Options in ISEEM Global Energy Model: 2010-2050 Scenario Analysis for Least-Cost Carbon Reduction in Iron and Steel Sector

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

Karali, Nihan; Xu, Tengfang; Sathaye, Jayant

The goal of the modeling work carried out in this project was to quantify long-term scenarios for the future emission reduction potentials in the iron and steel sector. The main focus of the project is to examine the impacts of carbon reduction options in the U.S. iron and steel sector under a set of selected scenarios. In order to advance the understanding of carbon emission reduction potential on the national and global scales, and to evaluate the regional impacts of potential U.S. mitigation strategies (e.g., commodity and carbon trading), we also included and examined the carbon reduction scenarios in China’smore » and India’s iron and steel sectors in this project. For this purpose, a new bottom-up energy modeling framework, the Industrial Sector Energy Efficiency Modeling (ISEEM), (Karali et al. 2012) was used to provide detailed annual projections starting from 2010 through 2050. We used the ISEEM modeling framework to carry out detailed analysis, on a country-by-country basis, for the U.S., China’s, and India’s iron and steel sectors. The ISEEM model applicable to iron and steel section, called ISEEM-IS, is developed to estimate and evaluate carbon emissions scenarios under several alternative mitigation options - including policies (e.g., carbon caps), commodity trading, and carbon trading. The projections will help us to better understand emission reduction potentials with technological and economic implications. The database for input of ISEEM-IS model consists of data and information compiled from various resources such as World Steel Association (WSA), the U.S. Geological Survey (USGS), China Steel Year Books, India Bureau of Mines (IBM), Energy Information Administration (EIA), and recent LBNL studies on bottom-up techno-economic analysis of energy efficiency measures in the iron and steel sector of the U.S., China, and India, including long-term steel production in China. In the ISEEM-IS model, production technology and manufacturing details are represented, in addition to the extensive data compiled from recent studies on bottom-up representation of efficiency measures for the sector. We also defined various mitigation scenarios including long-term production trends to project country-specific production, energy use, trading, carbon emissions, and costs of mitigation. Such analyses can provide useful information to assist policy-makers when considering and shaping future emissions mitigation strategies and policies. The technical objective is to analyze the costs of production and CO 2 emission reduction in the U.S, China, and India’s iron and steel sectors under different emission reduction scenarios, using the ISEEM-IS as a cost optimization model. The scenarios included in this project correspond to various CO 2 emission reduction targets for the iron and steel sector under different strategies such as simple CO 2 emission caps (e.g., specific reduction goals), emission reduction via commodity trading, and emission reduction via carbon trading.« less

Spontaneous and controlled-diameter synthesis of single-walled and few-walled carbon nanotubes

NASA Astrophysics Data System (ADS)

Inoue, Shuhei; Lojindarat, Supanat; Kawamoto, Takahiro; Matsumura, Yukihiko; Charinpanitkul, Tawatchai

2018-05-01

In this study, we explored the spontaneous and controlled-diameter growth of carbon nanotubes. We evaluated the effects of catalyst density, reduction time, and a number of catalyst coating on the substrate (for multi-walled carbon nanotubes) on the diameter of single-walled carbon nanotubes and the number of layers in few-walled carbon nanotubes. Increasing the catalyst density and reduction time increased the diameters of the carbon nanotubes, with the average diameter increasing from 1.05 nm to 1.86 nm for single-walled carbon nanotubes. Finally, we succeeded in synthesizing a significant double-walled carbon nanotube population of 24%.

Process for Making Carbon-Carbon Turbocharger Housing Unit for Intermittent Combustion Engines

NASA Technical Reports Server (NTRS)

Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

1999-01-01

An improved. lightweight, turbine housing unit for an intermittent combustion reciprocating internal combustion engine turbocharger is prepared from a lay-up or molding of carbon-carbon composite materials in a single-piece or two-piece process. When compared to conventional steel or cast iron, the use of carbon-carbon composite materials in a turbine housing unit reduces the overall weight of the engine and reduces the heat energy loss used in the turbo-charging process. This reduction in heat energy loss and weight reduction provides for more efficient engine operation.

Carbon-Carbon Turbocharger Housing Unit for Intermittent Combustion Engines

NASA Technical Reports Server (NTRS)

Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)

1998-01-01

An improved, lightweight, turbine housing unit for an intermittent combustion reciprocating internal combustion engine turbocharger is prepared from a lay-up or molding of carbon-carbon composite materials in a single-piece or two-piece process. When compared to conventional steel or cast iron, the use of carbon-carbon composite materials in a turbine housing unit reduces the overall weight of the engine and reduces the heat energy loss used in the turbocharging process. This reduction in heat energy loss and weight reduction provides for more efficient engine operation.

The impact of local government investment on the carbon emissions reduction effect: An empirical analysis of panel data from 30 provinces and municipalities in China.

PubMed

He, Lingyun; Yin, Fang; Zhong, Zhangqi; Ding, Zhihua

2017-01-01

Among studies of the factors that influence carbon emissions and related regulations, economic aggregates, industrial structures, energy structures, population levels, and energy prices have been extensively explored, whereas studies from the perspective of fiscal leverage, particularly of local government investment (LGI), are rare. Of the limited number of studies on the effect of LGI on carbon emissions, most focus on its direct effect. Few studies consider regulatory effects, and there is a lack of emphasis on local areas. Using a cointegration test, a panel data model and clustering analysis based on Chinese data between 2000 and 2013, this study measures the direct role of LGI in carbon dioxide (CO2) emissions reduction. First, overall, within the sample time period, a 1% increase in LGI inhibits carbon emissions by 0.8906% and 0.5851% through its influence on the industrial structure and energy efficiency, respectively, with the industrial structure path playing a greater role than the efficiency path. Second, carbon emissions to some extent exhibit inertia. The previous year's carbon emissions impact the following year's carbon emissions by 0.5375%. Thus, if a reduction in carbon emissions in the previous year has a positive effect, then the carbon emissions reduction effect generated by LGI in the following year will be magnified. Third, LGI can effectively reduce carbon emissions, but there are significant regional differences in its impact. For example, in some provinces, such as Sichuan and Anhui, economic growth has not been decoupled from carbon emissions. Fourth, the carbon emissions reduction effect in the 30 provinces and municipalities sampled in this study can be classified into five categories-strong, relatively strong, medium, relatively weak and weak-based on the degree of local governments' regulation of carbon emissions. The carbon emissions reduction effect of LGI is significant in the western and central regions of China but not in the eastern and northeast regions. This study helps overcome the limitations of previous studies on the regulatory effects of LGI on carbon emissions, and the constructed model may more closely reflect actual economic conditions. Moreover, the current study can benefit countries similar to China that aim to objectively identify the impacts of their LGI on carbon emissions, and such countries can use it as a reference in the formulation of investment policies based on their economic and industrial characteristics.

The impact of local government investment on the carbon emissions reduction effect: An empirical analysis of panel data from 30 provinces and municipalities in China

PubMed Central

He, Lingyun; Yin, Fang; Zhong, Zhangqi; Ding, Zhihua

2017-01-01

Among studies of the factors that influence carbon emissions and related regulations, economic aggregates, industrial structures, energy structures, population levels, and energy prices have been extensively explored, whereas studies from the perspective of fiscal leverage, particularly of local government investment (LGI), are rare. Of the limited number of studies on the effect of LGI on carbon emissions, most focus on its direct effect. Few studies consider regulatory effects, and there is a lack of emphasis on local areas. Using a cointegration test, a panel data model and clustering analysis based on Chinese data between 2000 and 2013, this study measures the direct role of LGI in carbon dioxide (CO2) emissions reduction. First, overall, within the sample time period, a 1% increase in LGI inhibits carbon emissions by 0.8906% and 0.5851% through its influence on the industrial structure and energy efficiency, respectively, with the industrial structure path playing a greater role than the efficiency path. Second, carbon emissions to some extent exhibit inertia. The previous year’s carbon emissions impact the following year’s carbon emissions by 0.5375%. Thus, if a reduction in carbon emissions in the previous year has a positive effect, then the carbon emissions reduction effect generated by LGI in the following year will be magnified. Third, LGI can effectively reduce carbon emissions, but there are significant regional differences in its impact. For example, in some provinces, such as Sichuan and Anhui, economic growth has not been decoupled from carbon emissions. Fourth, the carbon emissions reduction effect in the 30 provinces and municipalities sampled in this study can be classified into five categories—strong, relatively strong, medium, relatively weak and weak—based on the degree of local governments’ regulation of carbon emissions. The carbon emissions reduction effect of LGI is significant in the western and central regions of China but not in the eastern and northeast regions. This study helps overcome the limitations of previous studies on the regulatory effects of LGI on carbon emissions, and the constructed model may more closely reflect actual economic conditions. Moreover, the current study can benefit countries similar to China that aim to objectively identify the impacts of their LGI on carbon emissions, and such countries can use it as a reference in the formulation of investment policies based on their economic and industrial characteristics. PMID:28727783

Recovery of lead from lead paste in spent lead acid battery by hydrometallurgical desulfurization and vacuum thermal reduction.

PubMed

Ma, Yunjian; Qiu, Keqiang

2015-06-01

Lead sulfate, lead oxides and lead metal are the main component of lead paste in spent lead acid battery. When lead sulfate was desulfurized and transformed into lead carbonate by sodium carbonate, lead metal and lead oxides remained unchanged. Lead carbonate is easily decomposed to lead oxide and carbon dioxide under high temperature. Namely, vacuum thermal process is the reduction reaction of lead oxides. A compatible environmental process consisted of hydrometallurgical desulfurization and vacuum thermal reduction to recycle lead was investigated in this research. Lead paste was firstly desulfurized with sodium carbonate, by which, the content of sulfur declined from 7.87% to 0.26%. Then, the desulfurized lead paste was reduced by charcoal under vacuum. Under the optimized reaction conditions, i.e., vacuum thermal reduction at temperature 850°C under 20 Pa for 45 min, a 22.11×10(-2) g cm(-2) min(-1) reduction rate, and a 98.13% direct recovery ratio of fine lead (99.77%) had been achieved, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Electrochemical process for the preparation of nitrogen fertilizers

DOEpatents

Jiang, Junhua; Aulich, Ted R; Ignatchenko, Alexey V

2015-04-14

Methods and apparatus for the preparation of nitrogen fertilizers including ammonium nitrate, urea, urea-ammonium nitrate, and/or ammonia are disclosed. Embodiments include (1) ammonium nitrate produced via the reduction of a nitrogen source at the cathode and the oxidation of a nitrogen source at the anode; (2) urea or its isomers produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source: (3) ammonia produced via the reduction of nitrogen source at the cathode and the oxidation of a hydrogen source or a hydrogen equivalent such as carbon monoxide or a mixture of carbon monoxide and hydrogen at the anode; and (4) urea-ammonium nitrate produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source, and anodic oxidation of a nitrogen source.

Natural diamond formation by self-redox of ferromagnesian carbonate

NASA Astrophysics Data System (ADS)

Chen, Ming; Shu, Jinfu; Xie, Xiande; Tan, Dayong; Mao, Ho-kwang

2018-03-01

Formation of natural diamonds requires the reduction of carbon to its bare elemental form, and pressures (P) greater than 5 GPa to cross the graphite–diamond transition boundary. In a study of shocked ferromagnesian carbonate at the Xiuyan impact crater, we found that the impact pressure–temperature (P-T) of 25–45 GPa and 800–900 °C were sufficient to decompose ankerite Ca(Fe2+,Mg)(CO3)2 to form diamond in the absence of another reductant. The carbonate self-reduced to diamond by concurrent oxidation of Fe2+ to Fe3+ to form a high-P polymorph of magnesioferrite, MgFe3+2O4. Discovery of the subsolidus carbonate self-reduction mechanism indicates that diamonds could be ubiquitously present as a dominant host for carbon in the Earth’s lower mantle.

Enhancing Productivity: A Structured Approach to Downsizing.

ERIC Educational Resources Information Center

Oehm, J. Kent

1991-01-01

Organizations that downsize in a rational and orderly manner can increase productivity. School districts can initiate a cost-reduction and restructuring program with an analysis of the responsibilities of each employee followed by communicating with, and renewing the commitment of, remaining employees. (MLF)

40 CFR 71.22 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... commits a company to achieving before January 1, 1994 sufficient reductions in hazardous air pollutants... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL... this chapter. Act means the Clean Air Act, as amended, 42 U.S.C. 7401, et seq. Actual emissions means...

40 CFR 71.22 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... commits a company to achieving before January 1, 1994 sufficient reductions in hazardous air pollutants... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL... this chapter. Act means the Clean Air Act, as amended, 42 U.S.C. 7401, et seq. Actual emissions means...

40 CFR 71.22 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... commits a company to achieving before January 1, 1994 sufficient reductions in hazardous air pollutants... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL... this chapter. Act means the Clean Air Act, as amended, 42 U.S.C. 7401, et seq. Actual emissions means...

40 CFR 71.22 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... commits a company to achieving before January 1, 1994 sufficient reductions in hazardous air pollutants... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) FEDERAL... this chapter. Act means the Clean Air Act, as amended, 42 U.S.C. 7401, et seq. Actual emissions means...

Lessons learned from successful Papanicolaou cytology cervical cancer prevention in the Socialist Republic of Vietnam.

PubMed

Suba, Eric J; Raab, Stephen S

2012-04-01

In 1996, we documented that the burden of cervical cancer in Vietnam was associated with troop movements during the Vietnam War. Subsequently, establishment of Papanicolaou screening in southern Vietnam was associated with reductions in cervical cancer incidence from 29.2/100,000 in 1998 to 16/100,000 in 2003. This is one of the first English-language reports of a real-world cervical cancer prevention effort associated with a decisive impact on health outcomes in a contemporary developing country. if our ideological commitment is to improve health outcomes as rapidly as possible among as many people as possible, then Papanicolaou screening (with or without HPV or visual screening) must be implemented without further delay in any setting where cervical screening is appropriate but unavailable; consideration must be given to HPV vaccination after, rather than before, full coverage of target demographic groups by screening services has been achieved and/or the possibility has been excluded that HPV vaccination may be ineffective for cancer prevention. Competing ideological commitments engender imprudent yet commercially useful alternative strategies prone to decelerate global reductions in mortality by suppressing the more-rapid uptake of less-expensive open-source technology in favor of the less-rapid uptake of more-expensive proprietary technologies with uncertain real-world advantages and unfavorable real-world operational limitations. Global cervical cancer prevention efforts will become more effective if global health leaders, including the Bill & Melinda Gates Foundation, embrace an ideological commitment to improving health outcomes as rapidly as possible among as many people as possible and assimilate the policy implications of that commitment. Copyright © 2011 Wiley-Liss, Inc.

The Effect of a "Class Smoke Free Pledge" on Breath Carbon Monoxide in Arabic Male Adolescents.

PubMed

Al-Sheyab, Nihaya A; Khader, Yousef S; Shah, Smita; Roydhouse, Jessica K; Gallagher, Robyn

2018-04-02

Arabic male adolescents have a high smoking prevalence. Introduction of "Class smoke-free" pledges have been successful amongst European adolescents but have not been evaluated using objective valid measures. We tested the impact of adding a smoke free pledge strategy to a proven peer-led asthma and smoking prevention program on breath carbon monoxide level (BCO) in male high-school students in Jordan. We enrolled male students from four high-schools in Irbid, Jordan. Schools were randomly assigned to receive either TAJ (Triple A in Jordan, n = 218) or TAJ-Plus (with added class smoke-free pledge, n = 215). We hypothesized that students receiving TAJ-Plus would have greater reduction in BCO levels than those only receiving the TAJ intervention. Asthma and smoking status were assessed by self-administered questionnaires. Smoking outcomes were collected using a BCO Monitor. Both groups had significant reductions in BCO levels post-intervention (p < .0001), however, decreases were greater in TAJ-Plus group (3.9 ± 0.2 vs. 4.8 ± 0.2, p < .0001). Intervention effects on BCO over time did not vary by smoking status (p = .085), asthma status (p = .602), or a combination of the two (p = .702). An added smoke-free pledge strategy to a proven peer-led asthma education program appears to be a promising approach to motivate adolescents to abstain from smoking in Jordan. Future research is required to determine if these results can be extended to Jordanian adolescent females. A commitment by students via a "class smoke-free" pledge can be an added incentive to motivate adolescents in Arabic-speaking countries to abstain from smoking. Social influence approaches in schools can be useful in countering the aggressive tobacco marketing campaigns targeting Jordanian and other Arabic-speaking youth. The combination of "class smoke-free" pledges and an evidence-based peer-led asthma and smoking education can be implemented in schools to influence adolescents with asthma to abstain from smoking.

Extreme late-summer drought causes neutral annual carbon balance in southwestern ponderosa pine forests and grasslands

NASA Astrophysics Data System (ADS)

Kolb, Thomas; Dore, Sabina; Montes-Helu, Mario

2013-03-01

We assessed the impacts of extreme late-summer drought on carbon balance in a semi-arid forest region in Arizona. To understand drought impacts over extremes of forest cover, we measured net ecosystem production (NEP), gross primary production (GPP), and total ecosystem respiration (TER) with eddy covariance over five years (2006-10) at an undisturbed ponderosa pine (Pinus ponderosa) forest and at a former forest converted to grassland by intense burning. Drought shifted annual NEP from a weak source of carbon to the atmosphere to a neutral carbon balance at the burned site and from a carbon sink to neutral at the undisturbed site. Carbon fluxes were particularly sensitive to drought in August. Drought shifted August NEP at the undisturbed site from sink to source because the reduction of GPP (70%) exceeded the reduction of TER (35%). At the burned site drought shifted August NEP from weak source to neutral because the reduction of TER (40%) exceeded the reduction of GPP (20%). These results show that the lack of forest recovery after burning and the exposure of undisturbed forests to late-summer drought reduce carbon sink strength and illustrate the high vulnerability of forest carbon sink strength in the southwest US to predicted increases in intense burning and precipitation variability.

Carbon dioxide reduction by the Bosch process

NASA Technical Reports Server (NTRS)

Manning, M. P.; Reid, R. C.

1975-01-01

Prototype units for carrying out the reduction of carbon dioxide to elementary carbon have been built and operated successfully. In some cases, however, startup difficulties have been reported. Moreover, the recycle reactor product has been reported to contain only small amounts of water and undesirably high yields of methane. This paper presents the results of the first phase of an experimental study that was carried out to define the mechanisms occurring in the reduction process. Conclusions are drawn and possible modifications to the present recycle process are suggested.

40 CFR 60.2115 - What if I do not use a wet scrubber, fabric filter, activated carbon injection, selective...

Code of Federal Regulations, 2013 CFR

2013-07-01

..., fabric filter, activated carbon injection, selective noncatalytic reduction, or an electrostatic... Limitations and Operating Limits § 60.2115 What if I do not use a wet scrubber, fabric filter, activated... carbon injection, selective noncatalytic reduction, fabric filter, or an electrostatic precipitator or...

Review of Manganese Processing for Production of TRIP/TWIP Steels, Part 2: Reduction Studies

NASA Astrophysics Data System (ADS)

Elliott, R.; Coley, K.; Mostaghel, S.; Barati, M.

2018-02-01

Production of ultrahigh-manganese steels is expected to result in significant increase in demand for low-carbon (LC) ferromanganese (FeMn) and silicomanganese (SiMn). Current manganese processing techniques are energy intensive and typically yield a high-carbon product. The present work therefore reviews available literature regarding carbothermic reduction of Mn oxides and ores, with the objective of identifying opportunities for future process development to mitigate the cost of LC FeMn and SiMn. In general, there is consensus that carbothermic reduction of Mn oxides and ores is limited by gasification of carbon. Conditions which enhance or bypass this step (e.g., by application of CH4) show higher rates of reduction at lower temperatures. This phenomenon has potential application in solid-state reduction of Mn ore. Other avenues for process development include optimization of the prereduction step in conventional FeMn production and metallothermic reduction as a secondary reduction step.

Modeling GHG Emissions and Carbon Changes in Agricultural and Forest Systems to Guide Mitigation and Adaptation: Synthesis and Future Needs

USDA-ARS?s Scientific Manuscript database

Agricultural production systems and land use change for agriculture and forestry are important sources of anthropogenic greenhouse gas (GHG) emissions. Recent commitments by the European Union, the United States, and China to reduce GHG emissions highlight the need to improve estimates of current em...

Formate: an Energy Storage and Transport Bridge between Carbon Dioxide and a Formate Fuel Cell in a Single Device.

PubMed

Vo, Tracy; Purohit, Krutarth; Nguyen, Christopher; Biggs, Brenna; Mayoral, Salvador; Haan, John L

2015-11-01

We demonstrate the first device to our knowledge that uses a solar panel to power the electrochemical reduction of dissolved carbon dioxide (carbonate) into formate that is then used in the same device to operate a direct formate fuel cell (DFFC). The electrochemical reduction of carbonate is carried out on a Sn electrode in a reservoir that maintains a constant carbon balance between carbonate and formate. The electron-rich formate species is converted by the DFFC into electrical energy through electron release. The product of DFFC operation is the electron-deficient carbonate species that diffuses back to the reservoir bulk. It is possible to continuously charge the device using alternative energy (e.g., solar) to convert carbonate to formate for on-demand use in the DFFC; the intermittent nature of alternative energy makes this an attractive design. In this work, we demonstrate a proof-of-concept device that performs reduction of carbonate, storage of formate, and operation of a DFFC. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improving and Assessing Aircraft-based Greenhouse Gas Emission Rate Measurements at Indianapolis as part of the INFLUX project.

NASA Astrophysics Data System (ADS)

Heimburger, A. M. F.; Shepson, P. B.; Stirm, B. H.; Susdorf, C.; Cambaliza, M. O. L.

2015-12-01

Since the Copenhagen accord in 2009, several countries have affirmed their commitment to reduce their greenhouse gas emissions. The United States and Canada committed to reduce their emissions by 17% below 2005 levels, by 2020, Europe by 14% and China by ~40%. To achieve such targets, coherent and effective strategies in mitigating atmospheric carbon emissions must be implemented in the next decades. Whether such goals are actually achieved, they require that reductions are "measurable", "reportable", and "verifiable". Management of greenhouse gas emissions must focus on urban environments since ~74% of CO2 emissions worldwide will be from cities, while measurement approaches are highly uncertain (~50% to >100%). The Indianapolis Flux Experiment (INFLUX) was established to develop, assess and improve top-down and bottom-up quantifications of urban greenhouse gas emissions. Based on an aircraft mass balance approach, we performed a series of experiments focused on the improvement of CO2, CH4 and CO emission rates quantification from Indianapolis, our final objective being to drastically improve the method overall uncertainty from the previous estimate of 50%. In November-December 2014, we conducted nine methodologically identical mass balance experiments in a short period of time (24 days, one downwind distance) for assumed constant total emission rate conditions, as a means to obtain an improved standard deviation of the mean determination. By averaging the individual emission rate determinations, we were able to obtain a method precision of 17% and 16% for CO2 and CO, respectively, at the 95%C.L. CH4 emission rates are highly variable day to day, leading to precision of 60%. Our results show that repetitive sampling can enable improvement in precision of the aircraft top-down methods through averaging.

PREFACE: 7th International Conference on Cooling & Heating Technologies (ICCHT 2014)

NASA Astrophysics Data System (ADS)

2015-09-01

The Kyoto protocol has initiated a pledge from almost all developing and developed countries to be committed to reducing CO2 emissions. Development of new renewable energy technologies are also of interest in this conference. Greenhouse gases have contributed to global warming and other man-made disasters. Cooling and Heating communities also have responsibilities towards the commitment of reducing the greenhouse gas emissions. In addition, depleting natural resources also act as a threat to the Cooling and Heating industries, causing them to develop highly efficient equipment and innovative technologies. The 1st International Conference on Cooling & Heating Technologies was held in Hanoi Vietnam (Jan. 2005). Whereas the 2nd, 3rd, 4th and 5th ICCHT conferences were held in Dalian, China (Jul. 2006), Tokyo, Japan (Jul. 2007), Jinhae, Korea (Oct. 2008) and Bandung, Indonesia (Dec. 2010) respectively. The 6th International Conference on Cooling & Heating Technologies (ICCTH2012) was held in Xi'an in China on November 9-12, 2012. It is our pleasure to welcome you to the 7th International Conference on Cooling & Heating Technologies (ICCTH2014) on 4th - 6th November 2014 at the Grand Dorsett Subang Hotel, Subang Jaya, Selangor Darul Ehsan, Malaysia The Theme of the Conference is ''Sustainability and Innovation in Heating & Cooling Technologies''. The sub-themes are:- • CO2 Reduction and Low Carbon Technologies • HVAC System and Natural Ventilation • Energy & Alternative Energy • Computational Fluid Dynamics • Low Temperature & Refrigeration Engineering In conjunction with the Conference, an Exhibition will be organized as an integral part of the Conference. Project experiences, product solutions, new applications and state-of-the art information will be highlighted.

Nudging guideline-concordant antibiotic prescribing: a randomized clinical trial.

PubMed

Meeker, Daniella; Knight, Tara K; Friedberg, Mark W; Linder, Jeffrey A; Goldstein, Noah J; Fox, Craig R; Rothfeld, Alan; Diaz, Guillermo; Doctor, Jason N

2014-03-01

"Nudges" that influence decision making through subtle cognitive mechanisms have been shown to be highly effective in a wide range of applications, but there have been few experiments to improve clinical practice. To investigate the use of a behavioral "nudge" based on the principle of public commitment in encouraging the judicious use of antibiotics for acute respiratory infections (ARIs). Randomized clinical trial in 5 outpatient primary care clinics. A total of 954 adults had ARI visits during the study timeframe: 449 patients were treated by clinicians randomized to the posted commitment letter (335 in the baseline period, 114 in the intervention period); 505 patients were treated by clinicians randomized to standard practice control (384 baseline, 121 intervention). The intervention consisted of displaying poster-sized commitment letters in examination rooms for 12 weeks. These letters, featuring clinician photographs and signatures, stated their commitment to avoid inappropriate antibiotic prescribing for ARIs. Antibiotic prescribing rates for antibiotic-inappropriate ARI diagnoses in baseline and intervention periods, adjusted for patient age, sex, and insurance status. Baseline rates were 43.5% and 42.8% for control and poster, respectively. During the intervention period, inappropriate prescribing rates increased to 52.7% for controls but decreased to 33.7% in the posted commitment letter condition. Controlling for baseline prescribing rates, we found that the posted commitment letter resulted in a 19.7 absolute percentage reduction in inappropriate antibiotic prescribing rate relative to control (P = .02). There was no evidence of diagnostic coding shift, and rates of appropriate antibiotic prescriptions did not diminish over time. Displaying poster-sized commitment letters in examination rooms decreased inappropriate antibiotic prescribing for ARIs. The effect of this simple, low-cost intervention is comparable in magnitude to costlier, more intensive quality-improvement efforts. clinicaltrials.gov identifier: NCT01767064.

State Right to Refuse Medication Laws and Procedures: Impact on Homicide and Suicide.

PubMed

Edwards, Griffin

2016-09-01

As part of the expansive overhaul of the mental health system that occurred in the latter half of the 20th Century, many states passed laws that allow, under certain conditions, voluntary and involuntarily committed patients to refuse medication. While some predicted the consequences of these laws would be dire, the effect on violent behavior remains untested. The aim is to decipher any differences state right to refuse medication laws may have on violence. Using the homicide rate of every US state between 1972 and 2001 (N = 1,479), and the suicide rate between 1981 and 2001 (N = 1,071). The study compares the difference in homicide/suicide rates before and after a law change to that same difference in a set of control states to estimate the effect of laws aimed at extending the right to refuse medication to both voluntary and involuntarily committed mental health patients. Laws designed to allow voluntarily committed patients to refuse medication are associated with a 0.8 increase in homicides per 100,000 of the state population while laws dictating an involuntarily committed patient's right to request refusal of medication are negative but statistically insignificant using standard t test. Laws designed to allow voluntarily committed patients to refuse medication have no statistically significant effect on suicides while laws dictating an involuntarily committed patient's right to request refusal of medication, specifically when the request is reviewed by independent mental health professionals, are associated with a statistically significant reduction in suicides. Allowing voluntarily committed patients to refuse medication may entice some to enter in-patient facilities, but the brief and optional exposure to medication and their side effects may actually discourage treatment and increase violence.

Enhancing the open space of Jabodetabek area, Indonesia

NASA Astrophysics Data System (ADS)

Wartaman, A. S.; Situmorang, R.; Suharto, B. B.

2018-01-01

Jabodetabek area is planned to be developed as a sustainable development region. The Government of Indonesia (GoI) committed in Paris Conference that the target of GHG emissions would be reduced by 29% up to 2030 with her own efforts and by 41% with supported by international assistance. This research attempts to apply specific methods such as stratified planting method to improve the quality of green open space by increasing the absorbed carbon level. The study showed that with the planting vegetation of stratified model, the total capacity of the mainland to absorb CO2 gas is quite significant increase with approximately 20% compared to that of homogeneous vegetation. The stratified planting model is worthwhile to achieve the commitment of the GoI mentioned above.

Energy Challenges: Isolating Results Due to Behavior Change

ERIC Educational Resources Information Center

Boulton, Kelly; Pallant, Eric; Bradshaw-Wilson, Casey; Choate, Beth; Carbone, Ian

2017-01-01

Purpose: Approximately 700 colleges and universities have committed to climate neutrality, which will require significant reductions in energy consumption. This paper aims to explore the effectiveness of an Annual Energy Challenge in curtailing electricity use by changing consumption behaviors at one liberal arts college.…

Burnout among the Addiction Counseling Workforce: The Differential Roles of Mindfulness and Values-based Processes and Work-site Factors*

PubMed Central

Vilardaga, Roger; Luoma, Jason B.; Hayes, Steven C.; Pistorello, Jacqueline; Levin, Michael E.; Hildebrandt, Mikaela J.; Kohlenberg, Barbara; Roget, Nancy A.; Bond, Frank

2011-01-01

Although work-site factors have been shown to be a consistent predictor of burnout, the importance of mindfulness and values-based processes among addiction counselors has been little examined. In this study we explored how strongly experiential avoidance, cognitive fusion and values commitment related to burnout after controlling for well-established work-site factors (job control, co-worker support, supervisor support, salary, workload and tenure). We conducted a cross-sectional survey among 699 addiction counselors working for urban substance abuse treatment providers in six states of the U.S.A. Results corroborated the importance of work-site factors for burnout reduction in this specific population, but we found that mindfulness and values-based processes had a stronger and more consistent relationship with burnout as compared to work-site factors. We conclude that interventions that target experiential avoidance, cognitive fusion and values commitment may provide a possible new direction for the reduction of burnout among addiction counselors. PMID:21257281

Acceptance and commitment group therapy for health anxiety--results from a pilot study.

PubMed

Eilenberg, T; Kronstrand, L; Fink, P; Frostholm, L

2013-06-01

Health anxiety (or hypochondriasis) is prevalent, may be persistent and disabling for the sufferers and associated with high societal costs. Acceptance and Commitment Therapy (ACT) is a new third-wave behavioral cognitive therapy that has not yet been tested in health anxiety. 34 consecutive Danish patients with severe health anxiety were referred from general practitioners or hospital departments and received a ten-session ACT group therapy. Patients were followed up by questionnaires for 6 months. There were significant reductions in health anxiety, somatic symptoms and emotional distress at 6 months compared to baseline: a 49% reduction in health anxiety (Whiteley-7 Index), a 47% decrease in emotional distress (SCL-8), and a 40% decrease in somatic symptoms (SCL-90R Somatization Subscale). The patients' emotional representations and perception of the consequences of their illness (IPQ) improved significantly, and 87% of the patients were very or extremely satisfied with the treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Kinetics study of carbon raiser on the reduction of nickel laterite from Pomalaa, Southeast Sulawesi

NASA Astrophysics Data System (ADS)

Petrus, H. T. B. M.; Rhamdani, A. R.; Putera, A. D. P.; Warmada, I. W.; Yuliansyad, A. T.; Perdana, I.

2016-11-01

As one of the top ten on nickel laterite ore resources in the world, Indonesia must have been initiating the nickel processing in total amount of about 1.5 million tonnes. In regard to the low nickel laterite processing, one of the possible product is nickel pig iron (NPI) needed for the stainless steel industries. In this study carbon raiser that is waste from oil industries was used to replace metalurgical coke. The kinetic of nickel laterite reduction using carbon raiser was studied and compared with anthrasite coal. In this work, the author conducted the reduction of nickel laterite ores by both carbon raiser and anthrasite coal as reductant, in air and CO2 atmosphere, within the temperature ranged from 800°C and 1000°C. Two models were applied, sphere particle geometry model and Ginstling-Brounhstein diffusion model, to study the kinetic parameters. The results indicated that type of reductants and reduction atmosphere greatly influence the kinetic parameters. The obtained values of activation energy were varied between 17.44-18.12 kcal/mol.

Assessing Earthquake-Induced Tree Mortality in Temperate Forest Ecosystems: A Case Study from Wenchuan, China

DOE PAGES

Zeng, Hongcheng; Lu, Tao; Jenkins, Hillary; ...

2016-03-17

Earthquakes can produce significant tree mortality, and consequently affect regional carbon dynamics. Unfortunately, detailed studies quantifying the influence of earthquake on forest mortality are currently rare. The committed forest biomass carbon loss associated with the 2008 Wenchuan earthquake in China is assessed by a synthetic approach in this study that integrated field investigation, remote sensing analysis, empirical models and Monte Carlo simulation. The newly developed approach significantly improved the forest disturbance evaluation by quantitatively defining the earthquake impact boundary and detailed field survey to validate the mortality models. Based on our approach, a total biomass carbon of 10.9 Tg·C wasmore » lost in Wenchuan earthquake, which offset 0.23% of the living biomass carbon stock in Chinese forests. Tree mortality was highly clustered at epicenter, and declined rapidly with distance away from the fault zone. It is suggested that earthquakes represent a signif icant driver to forest carbon dynamics, and the earthquake-induced biomass carbon loss should be included in estimating forest carbon budgets.« less

Assessing Earthquake-Induced Tree Mortality in Temperate Forest Ecosystems: A Case Study from Wenchuan, China

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

Zeng, Hongcheng; Lu, Tao; Jenkins, Hillary

Earthquakes can produce significant tree mortality, and consequently affect regional carbon dynamics. Unfortunately, detailed studies quantifying the influence of earthquake on forest mortality are currently rare. The committed forest biomass carbon loss associated with the 2008 Wenchuan earthquake in China is assessed by a synthetic approach in this study that integrated field investigation, remote sensing analysis, empirical models and Monte Carlo simulation. The newly developed approach significantly improved the forest disturbance evaluation by quantitatively defining the earthquake impact boundary and detailed field survey to validate the mortality models. Based on our approach, a total biomass carbon of 10.9 Tg·C wasmore » lost in Wenchuan earthquake, which offset 0.23% of the living biomass carbon stock in Chinese forests. Tree mortality was highly clustered at epicenter, and declined rapidly with distance away from the fault zone. It is suggested that earthquakes represent a signif icant driver to forest carbon dynamics, and the earthquake-induced biomass carbon loss should be included in estimating forest carbon budgets.« less

Reduction of Carbon Dioxide by a Molybdenum-Containing Formate Dehydrogenase: A Kinetic and Mechanistic Study.

PubMed

Maia, Luisa B; Fonseca, Luis; Moura, Isabel; Moura, José J G

2016-07-20

Carbon dioxide accumulation is a major concern for the ecosystems, but its abundance and low cost make it an interesting source for the production of chemical feedstocks and fuels. However, the thermodynamic and kinetic stability of the carbon dioxide molecule makes its activation a challenging task. Studying the chemistry used by nature to functionalize carbon dioxide should be helpful for the development of new efficient (bio)catalysts for atmospheric carbon dioxide utilization. In this work, the ability of Desulfovibrio desulfuricans formate dehydrogenase (Dd FDH) to reduce carbon dioxide was kinetically and mechanistically characterized. The Dd FDH is suggested to be purified in an inactive form that has to be activated through a reduction-dependent mechanism. A kinetic model of a hysteretic enzyme is proposed to interpret and predict the progress curves of the Dd FDH-catalyzed reactions (initial lag phase and subsequent faster phase). Once activated, Dd FDH is able to efficiently catalyze, not only the formate oxidation (kcat of 543 s(-1), Km of 57.1 μM), but also the carbon dioxide reduction (kcat of 46.6 s(-1), Km of 15.7 μM), in an overall reaction that is thermodynamically and kinetically reversible. Noteworthy, both Dd FDH-catalyzed formate oxidation and carbon dioxide reduction are completely inactivated by cyanide. Current FDH reaction mechanistic proposals are discussed and a different mechanism is here suggested: formate oxidation and carbon dioxide reduction are proposed to proceed through hydride transfer and the sulfo group of the oxidized and reduced molybdenum center, Mo(6+)═S and Mo(4+)-SH, are suggested to be the direct hydride acceptor and donor, respectively.

Advanced air revitalization system modeling and testing

NASA Technical Reports Server (NTRS)

Dall-Baumann, Liese; Jeng, Frank; Christian, Steve; Edeer, Marybeth; Lin, Chin

1990-01-01

To support manned lunar and Martian exploration, an extensive evaluation of air revitalization subsystems (ARS) is being conducted. The major operations under study include carbon dioxide removal and reduction; oxygen and nitrogen production, storage, and distribution; humidity and temperature control; and trace contaminant control. A comprehensive analysis program based on a generalized block flow model was developed to facilitate the evaluation of various processes and their interaction. ASPEN PLUS was used in modelling carbon dioxide removal and reduction. Several life support test stands were developed to test new and existing technologies for their potential applicability in space. The goal was to identify processes which use compact, lightweight equipment and maximize the recovery of oxygen and water. The carbon dioxide removal test stands include solid amine/vacuum desorption (SAVD), regenerative silver oxide chemisorption, and electrochemical carbon dioxide concentration (EDC). Membrane-based carbon dioxide removal and humidity control, catalytic reduction of carbon dioxide, and catalytic oxidation of trace contaminants were also investigated.

Supramolecular Porphyrin Cages Assembled at Molecular–Materials Interfaces for Electrocatalytic CO Reduction

DOE PAGES

Gong, Ming; Cao, Zhi; Liu, Wei; ...

2017-09-13

Conversion of carbon monoxide (CO), a major one-carbon product of carbon dioxide (CO 2) reduction, into value-added multicarbon species is a challenge to addressing global energy demands and climate change. Here in this paper, we report a modular synthetic approach for aqueous electrochemical CO reduction to carbon-carbon coupled products via self-assembly of supramolecular cages at molecular-materials interfaces. Heterobimetallic cavities formed by face-to-face coordination of thiol-terminated metalloporphyrins to copper electrodes through varying organic struts convert CO to C2 products with high faradaic efficiency (FE = 83% total with 57% to ethanol) and current density (1.34 mA/cm 2) at a potential ofmore » -0.40 V vs RHE. The cage-functionalized electrodes offer an order of magnitude improvement in both selectivity and activity for electrocatalytic carbon fixation compared to parent copper surfaces or copper functionalized with porphyrins in an edge-on orientation.« less

Carbon flow analysis and Carbon emission reduction of FCC in Chinese oil refineries

NASA Astrophysics Data System (ADS)

Jia, Fengrui; Wei, Na; Ma, Danzhu; Liu, Guangxin; Wu, Ming; Yue, Qiang

2017-08-01

The major problem of the energy production in oil refineries is the high emission of CO2 in China. The fluid catalytic cracking unit (FCC) is the key source of carbon emission in the oil refineries. According to the statistical data, the carbon emission of FCC unit accounts for more than 31% for the typical oil refineries. The carbon flow of FCC in the typical Chinese oil refineries were evaluated and analysed, which aimed at the solution of CO2 emission reduction. The method of substances flow analysis (SFA) and the mathematical programming were used to evaluate the carbon metabolism and optimize the carbon emission. The results indicated that the combustion emission of the reaction-regeneration subsystem (RRS) was the major source of FCC. The quantity of CO2 emission of RSS was more than 90%. The combustion efficiency and the amount of residual oil affected the carbon emission of RRS most according to the optimized analysis of carbon emission reduction. Moreover, the fractionation subsystem (TFS) had the highest environmental efficiency and the absorption-stabilization subsystem (ASS) had the highest resource efficiency (approximately to 1) of carbon.

Regional drought-induced reduction in the biomass carbon sink of Canada's boreal forests.

PubMed

Ma, Zhihai; Peng, Changhui; Zhu, Qiuan; Chen, Huai; Yu, Guirui; Li, Weizhong; Zhou, Xiaolu; Wang, Weifeng; Zhang, Wenhua

2012-02-14

The boreal forests, identified as a critical "tipping element" of the Earth's climate system, play a critical role in the global carbon budget. Recent findings have suggested that terrestrial carbon sinks in northern high-latitude regions are weakening, but there has been little observational evidence to support the idea of a reduction of carbon sinks in northern terrestrial ecosystems. Here, we estimated changes in the biomass carbon sink of natural stands throughout Canada's boreal forests using data from long-term forest permanent sampling plots. We found that in recent decades, the rate of biomass change decreased significantly in western Canada (Alberta, Saskatchewan, and Manitoba), but there was no significant trend for eastern Canada (Ontario and Quebec). Our results revealed that recent climate change, and especially drought-induced water stress, is the dominant cause of the observed reduction in the biomass carbon sink, suggesting that western Canada's boreal forests may become net carbon sources if the climate change-induced droughts continue to intensify.

Highly selective and active CO2 reduction electrocatalysts based on cobalt phthalocyanine/carbon nanotube hybrid structures

PubMed Central

Zhang, Xing; Wu, Zishan; Zhang, Xiao; Li, Liewu; Li, Yanyan; Xu, Haomin; Li, Xiaoxiao; Yu, Xiaolu; Zhang, Zisheng; Liang, Yongye; Wang, Hailiang

2017-01-01

Electrochemical reduction of carbon dioxide with renewable energy is a sustainable way of producing carbon-neutral fuels. However, developing active, selective and stable electrocatalysts is challenging and entails material structure design and tailoring across a range of length scales. Here we report a cobalt-phthalocyanine-based high-performance carbon dioxide reduction electrocatalyst material developed with a combined nanoscale and molecular approach. On the nanoscale, cobalt phthalocyanine (CoPc) molecules are uniformly anchored on carbon nanotubes to afford substantially increased current density, improved selectivity for carbon monoxide, and enhanced durability. On the molecular level, the catalytic performance is further enhanced by introducing cyano groups to the CoPc molecule. The resulting hybrid catalyst exhibits >95% Faradaic efficiency for carbon monoxide production in a wide potential range and extraordinary catalytic activity with a current density of 15.0 mA cm−2 and a turnover frequency of 4.1 s−1 at the overpotential of 0.52 V in a near-neutral aqueous solution. PMID:28272403

Mo(CO)/sub 6/-promoted reductive cleavage of the carbon-sulfur bond

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

Luh, T.Y.; Wong, C.S.

1985-12-13

In order to study the reductive cleavage of carbon-sulfur bonds by Mo(CO/sub 6/, various organosulfur compounds are reacted with Mo(CO)/sub 6/ in THF. Results of these experiments demonstrate that benzylic-, aryl-, or ..cap alpha..-acyl-activated carbon-sulfur bonds are reduced by treatment with Mo(CO)/sub 6/. 1 table.

Sustainable forest management of tropical forests can reduce carbon emissions and stabilize timber production

Treesearch

N. Sasaki; G.P. Asner; Yude Pan; W. Knorr; P.B. Durst; H.O. Ma; I. Abe; A.J. Lowe; L.P. Koh

2016-01-01

The REDD+ scheme of the United Nations Framework Conventionon Climate Change has provided opportunities to manage tropical forests for timber production and carbon emission reductions. To determine the appropriate loggingtechniques, we analyzed potential timber production and carbon emission reductions under two logging techniques over a 40-year period of selective...

Reduction of Plutonium in Acidic Solutions by Mesoporous Carbons

DOE PAGES

Parsons-Moss, Tashi; Jones, Stephen; Wang, Jinxiu; ...

2015-12-19

Batch contact experiments with several porous carbon materials showed that carbon solids spontaneously reduce the oxidation state of plutonium in 1-1.5 M acid solutions, without significant adsorption. The final oxidation state and rate of Pu reduction varies with the solution matrix, and also depends on the surface chemistry and surface area of the carbon. It was demonstrated that acidic Pu(VI) solutions can be reduced to Pu(III) by passing through a column of porous carbon particles, offering an easy alternative to electrolysis with a potentiostat.

Reduced graphene oxide supported gold nanoparticles for electrocatalytic reduction of carbon dioxide

NASA Astrophysics Data System (ADS)

Saquib, Mohammad; Halder, Aditi

2018-02-01

Electrochemical reduction of carbon dioxide is one of the methods which have the capability to recycle CO2 into valuable products for energy and industrial applications. This research article describes about a new electrocatalyst "reduced graphene oxide supported gold nanoparticles" for selective electrochemical conversion of carbon dioxide to carbon monoxide. The main aim for conversion of CO2 to CO lies in the fact that the latter is an important component of syn gas (a mixture of hydrogen and carbon monoxide), which is then converted into liquid fuel via well-known industrial process called Fischer-Tropsch process. In this work, we have synthesized different composites of the gold nanoparticles supported on defective reduced graphene oxide to evaluate the catalytic activity of reduced graphene oxide (RGO)-supported gold nanoparticles and the role of defective RGO support towards the electrochemical reduction of CO2. Electrochemical and impedance measurements demonstrate that higher concentration of gold nanoparticles on the graphene support led to remarkable decrease in the onset potential of 240 mV and increase in the current density for CO2 reduction. Lower impedance and Tafel slope values also clearly support our findings for the better performance of RGOAu than bare Au for CO2 reduction.

40 CFR 63.75 - Enforceable commitments.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Pennsylvania Ave., NW., Washington, DC 20460 and the EPA Emission Standards Division (MD-13), Research Triangle... by a responsible official of the source, containing the following: (i) A statement providing the post... achieve before January 1, 1994, the stated post-reduction emission level(s) at the source, which will...

40 CFR 63.75 - Enforceable commitments.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Pennsylvania Ave., NW., Washington, DC 20460 and the EPA Emission Standards Division (MD-13), Research Triangle... by a responsible official of the source, containing the following: (i) A statement providing the post... achieve before January 1, 1994, the stated post-reduction emission level(s) at the source, which will...

40 CFR 63.75 - Enforceable commitments.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Pennsylvania Ave., NW., Washington, DC 20460 and the EPA Emission Standards Division (MD-13), Research Triangle... by a responsible official of the source, containing the following: (i) A statement providing the post... achieve before January 1, 1994, the stated post-reduction emission level(s) at the source, which will...

40 CFR 63.75 - Enforceable commitments.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Pennsylvania Ave., NW., Washington, DC 20460 and the EPA Emission Standards Division (MD-13), Research Triangle... by a responsible official of the source, containing the following: (i) A statement providing the post... achieve before January 1, 1994, the stated post-reduction emission level(s) at the source, which will...

40 CFR 63.75 - Enforceable commitments.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Pennsylvania Ave., NW., Washington, DC 20460 and the EPA Emission Standards Division (MD-13), Research Triangle... by a responsible official of the source, containing the following: (i) A statement providing the post... achieve before January 1, 1994, the stated post-reduction emission level(s) at the source, which will...

Microbiological Consequences of Different Housing Systems for Laying Hens: Field and Experimental Infection Studies

USDA-ARS?s Scientific Manuscript database

A significant proportion of human illnesses caused by Salmonella are linked to the consumption of contaminated eggs. In response, substantial government and private industry resources are committed to comprehensive Salmonella testing and risk reduction programs for commercial egg-laying flocks. Envi...

Toward a Conceptual Clarification of Employee Responses to Flexible Working Hours: A Work Adjustment Approach.

ERIC Educational Resources Information Center

Pierce, Jon L.; Newstrom, John W.

1980-01-01

Elaborates on a work adjustment model to explain how flexible working hours can influence employee satisfaction, performance, absenteeism, tenure, organizational commitment, and job involvement. Discusses need fulfillment, stress reduction, and the harmonization of work with human circadian rhythms. (Author/RC)

Role of a gas phase in the kinetics of zinc and iron reduction with carbon from slag melts

NASA Astrophysics Data System (ADS)

Chumarev, V. M.; Selivanov, E. N.

2013-03-01

The influence of the mass transfer conditions in the gas phase having formed at the carbon-slag melt interface on CO regeneration is approximately estimated in the framework of a two-stage scheme of metal reduction from slag melts by carbon. The effect of zinc vapors on the combined reduction of iron and zinc from slags is considered. The influence of the slag composition and temperature on the critical concentration of zinc oxide above which no iron forms as an individual phase is explained.

Developing country finance in a post-2020 global climate agreement

NASA Astrophysics Data System (ADS)

Hannam, Phillip M.; Liao, Zhenliang; Davis, Steven J.; Oppenheimer, Michael

2015-11-01

A central task for negotiators of the post-2020 global climate agreement is to construct a finance regime that supports low-carbon development in developing economies. As power sector investments between developing countries grow, the climate finance regime should incentivize the decarbonization of these major sources of finance by integrating them as a complement to the commitments of developed nations. The emergence of the Asian Infrastructure Investment Bank, South-South Cooperation Fund and other nascent institutions reveal the fissures that exist in rules and norms surrounding international finance in the power sector. Structuring the climate agreement in Paris to credit qualified finance from the developing world could have several advantages, including: (1) encouraging low-carbon cooperation between developing countries; (2) incentivizing emerging investors to prefer low-carbon investments; and (3) enabling more cost-effective attainment of national and global climate objectives. Failure to coordinate on standards now could hinder low-carbon development in the decades to come.

Properties and effects of remaining carbon from waste plastics gasifying on iron scale reduction.

PubMed

Zhang, Chongmin; Chen, Shuwen; Miao, Xincheng; Yuan, Hao

2011-06-01

The carbonous activities of three kinds of carbon-bearing materials gasified from plastics were tested with coal coke as reference. The results showed that the carbonous activities of these remaining carbon-bearing materials were higher than that of coal-coke. Besides, the fractal analyses showed that the porosities of remaining carbon-bearing materials were higher than that of coal-coke. It revealed that these kinds of remaining carbon-bearing materials are conducive to improve the kinetics conditions of gas-solid phase reaction in iron scale reduction. Copyright © 2011 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Committed CO2 Emissions of China's Coal-fired Power Plants

NASA Astrophysics Data System (ADS)

Suqin, J.

2016-12-01

The extent of global warming is determined by the cumulative effects of CO2 in the atmosphere. Coal-fired power plants, the largest anthropogenic source of CO2 emissions, produce large amount of CO2 emissions during their lifetimes of operation (committed emissions), which thus influence the future carbon emission space under specific targets on mitigating climate change (e.g., the 2 degree warming limit relative to pre-industrial levels). Comprehensive understanding of committed CO2 emissions for coal-fired power generators is urgently needed in mitigating global climate change, especially in China, the largest global CO2emitter. We calculated China's committed CO2 emissions from coal-fired power generators installed during 1993-2013 and evaluated their impact on future emission spaces at the provincial level, by using local specific data on the newly installed capacities. The committed CO2 emissions are calculated as the product of the annual coal consumption from newly installed capacities, emission factors (CO2emissions per unit crude coal consumption) and expected lifetimes. The sensitivities about generators lifetimes and the drivers on provincial committed emissions are also analyzed. Our results show that these relatively recently installed coal-fired power generators will lead to 106 Gt of CO2 emissions over the course of their lifetimes, which is more than three times the global CO2 emissions from fossil fuels in 2010. More than 80% (85 Gt) of their total committed CO2 will be emitted after 2013, which are referred to as the remaining emissions. Due to the uncertainties of generators lifetime, these remaining emissions would increase by 45 Gt if the lifetimes of China's coal-fired power generators were prolonged by 15 years. Furthermore, the remaining emissions are very different among various provinces owing to local developments and policy disparities. Provinces with large amounts of secondary industry and abundant coal reserves have higher committed emissions. The national and provincial CO2 emission mitigation objectives might be greatly restricted by existing and planned power plants in China. The policy implications of our results have also been discussed.

A Model for Climate Change Adaptation

NASA Astrophysics Data System (ADS)

Pasqualini, D.; Keating, G. N.

2009-12-01

Climate models predict serious impacts on the western U.S. in the next few decades, including increased temperatures and reduced precipitation. In combination, these changes are linked to profound impacts on fundamental systems, such as water and energy supplies, agriculture, population stability, and the economy. Global and national imperatives for climate change mitigation and adaptation are made actionable at the state level, for instance through greenhouse gas (GHG) emission regulations and incentives for renewable energy sources. However, adaptation occurs at the local level, where energy and water usage can be understood relative to local patterns of agriculture, industry, and culture. In response to the greenhouse gas emission reductions required by California’s Assembly Bill 32 (2006), Sonoma County has committed to sharp emissions reductions across several sectors, including water, energy, and transportation. To assist Sonoma County develop a renewable energy (RE) portfolio to achieve this goal we have developed an integrated assessment model, CLEAR (CLimate-Energy Assessment for Resiliency) model. Building on Sonoma County’s existing baseline studies of energy use, carbon emissions and potential RE sources, the CLEAR model simulates the complex interactions among technology deployment, economics and social behavior. This model enables assessment of these and other components with specific analysis of their coupling and feedbacks because, due to the complex nature of the problem, the interrelated sectors cannot be studied independently. The goal is an approach to climate change mitigation and adaptation that is replicable for use by other interested communities. The model user interfaces helps stakeholders and policymakers understand options for technology implementation.

Nitrous oxide production kinetics during nitrate reduction in river sediments.

PubMed

Laverman, Anniet M; Garnier, Josette A; Mounier, Emmanuelle M; Roose-Amsaleg, Céline L

2010-03-01

A significant amount of nitrogen entering river basins is denitrified in riparian zones. The aim of this study was to evaluate the influence of nitrate and carbon concentrations on the kinetic parameters of nitrate reduction as well as nitrous oxide emissions in river sediments in a tributary of the Marne (the Seine basin, France). In order to determine these rates, we used flow-through reactors (FTRs) and slurry incubations; flow-through reactors allow determination of rates on intact sediment slices under controlled conditions compared to sediment homogenization in the often used slurry technique. Maximum nitrate reduction rates (R(m)) ranged between 3.0 and 7.1microg Ng(-1)h(-1), and affinity constant (K(m)) ranged from 7.4 to 30.7mg N-NO(3)(-)L(-1). These values were higher in slurry incubations with an R(m) of 37.9microg Ng(-1)h(-1) and a K(m) of 104mg N-NO(3)(-)L(-1). Nitrous oxide production rates did not follow Michaelis-Menten kinetics, and we deduced a rate constant with an average of 0.7 and 5.4ng Ng(-1)h(-1) for FTR and slurry experiments respectively. The addition of carbon (as acetate) showed that carbon was not limiting nitrate reduction rates in these sediments. Similar rates were obtained for FTR and slurries with carbon addition, confirming the hypothesis that homogenization increases rates due to release of and increasing access to carbon in slurries. Nitrous oxide production rates in FTR with carbon additions were low and represented less than 0.01% of the nitrate reduction rates and were even negligible in slurries. Maximum nitrate reduction rates revealed seasonality with high potential rates in fall and winter and low rates in late spring and summer. Under optimal conditions (anoxia, non-limiting nitrate and carbon), nitrous oxide emission rates were low, but significant (0.01% of the nitrate reduction rates). Copyright 2009 Elsevier Ltd. All rights reserved.

A Ground-Up Model for Gun Violence Reduction: A Community-Based Public Health Approach.

PubMed

Byrdsong, T Rashad; Devan, Angela; Yamatani, Hide

2016-01-01

The suggested strategy for the reduction of violence is to collaboratively address the problem, based on an intervention system focused on prevention, rehabilitation, and development. This strategy is capable of engaging community residents in positive ways, and it empowers them to take ownership and sustain much-needed resident commitments to achieve long-term public safety. The community residents largely insist that over-reliance on law enforcement to control violence invites further affliction among Black youth and adults.

Assessment on the rates and potentials of soil organic carbon sequestration in agricultural lands in Japan using a process-based model and spatially explicit land-use change inventories - Part 2: Future potentials

NASA Astrophysics Data System (ADS)

Yagasaki, Y.; Shirato, Y.

2014-08-01

Future potentials of the sequestration of soil organic carbon (SOC) in agricultural lands in Japan were estimated using a simulation system we recently developed to simulate SOC stock change at country-scale under varying land-use change, climate, soil, and agricultural practices, in a spatially explicit manner. Simulation was run from 1970 to 2006 with historical inventories, and subsequently to 2020 with future scenarios of agricultural activity comprised of various agricultural policy targets advocated by the Japanese government. Furthermore, the simulation was run subsequently until 2100 while forcing no temporal changes in land-use and agricultural activity to investigate duration and course of SOC stock change at country scale. A scenario with an increased rate of organic carbon input to agricultural fields by intensified crop rotation in combination with the suppression of conversion of agricultural lands to other land-use types was found to have a greater reduction of CO2 emission by enhanced soil carbon sequestration, but only under a circumstance in which the converted agricultural lands will become settlements that were considered to have a relatively lower rate of organic carbon input. The size of relative reduction of CO2 emission in this scenario was comparable to that in another contrasting scenario (business-as-usual scenario of agricultural activity) in which a relatively lower rate of organic matter input to agricultural fields was assumed in combination with an increased rate of conversion of the agricultural fields to unmanaged grasslands through abandonment. Our simulation experiment clearly demonstrated that net-net-based accounting on SOC stock change, defined as the differences between the emissions and removals during the commitment period and the emissions and removals during a previous period (base year or base period of Kyoto Protocol), can be largely influenced by variations in future climate. Whereas baseline-based accounting, defined as differences between the net emissions in the accounting period and the ex ante estimation of net business-as-usual emissions for the same period, has robustness over variations in future climate and effectiveness to factor out some of the direct human-induced effects such as changing land-use and agricultural activity. Factors affecting uncertainties in the estimation of the country-scale potential of SOC sequestration were discussed, especially those related to estimation of the rate of organic carbon input to soils under different land-use types. Our study suggested that, in order to assist decision making of policy on agriculture, land management, and mitigation of global climate change, it is also important to take account of duration and time course of SOC sequestration, supposition on land-use change pattern in future, as well as feasibility of agricultural policy planning.

Predictors of motivation for abstinence at the end of outpatient substance abuse treatment

PubMed Central

Laudet, Alexandre B.; Stanick, Virginia

2010-01-01

Commitment to abstinence, a motivational construct, is a strong predictor of reductions in drug and alcohol use. Level of commitment to abstinence at treatment end predicts sustained abstinence, a requirement for recovery. This study sought to identify predictors of commitment to abstinence at treatment end to guide clinical practice and to inform the conceptualization of motivational constructs. Polysubstance users (N = 250) recruited at the start of outpatient treatment were re-interviewed at the end of services. Based on the extant literature, potential predictors were during treatment measures of substance use and related cognitions, psychological functioning, recovery supports, stress, quality of life satisfaction, and treatment experiences. In multivariate analyses, perceived harm of future drug use, abstinence self-efficacy, quality of life satisfaction, and number of network members in 12-step recovery contributed 26.6% of the variance explained in the dependent variable, a total of 49.6% when combined with the control variables (demographics and baseline level of the outcome). Gender subgroup analyses yielded largely similar results. Clinical implications of findings for maximizing commitment to abstinence when clients leave treatment are discussed as are future research directions. PMID:20185267

Positional effects of second-sphere amide pendants on electrochemical CO 2 reduction catalyzed by iron porphyrins

DOE PAGES

Nichols, Eva M.; Derrick, Jeffrey S.; Nistanaki, Sepand K.; ...

2018-01-01

The development of catalysts for electrochemical reduction of carbon dioxide offers an attractive approach to transforming this greenhouse gas into value-added carbon products with sustainable energy input.

Indirect carbon reduction by residential vegetation and planting strategies in Chicago, U.S.A

Treesearch

H.K. Jo; E.G. McPherson

2001-01-01

Concern about climate change has evoked interest in the potential for urban vegetation to help reduce the levels of atmospheric carbon. This study applied computer simulations to try to quantify the modifying effects of existing vegetation on the indirect reduction of atmospheric carbon for two residential neighborhoods in north-west Chicago. The effects of shading,...

PRODUCTION OF BORON CARBIDES IN CARBON REDUCTION OF RARE EARTH MIXTURES WITH BORON (in Russian)

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

Markovskii, L.Ya.; Vekshina, N.V.; Pron, G.F.

1962-09-01

Carbon reduction of CeO/sub 2/ or La/sub 2/O/sub 3/ mixtures with B at 1900 to 2000 deg C produced borocarbides similar to Ca, Sr, and Ba borocarbides. The synthesized products contained considerable amounts of chemically unstable compounds that in hydrolytic disintegration transform into a boronmetal solution and carbon. (R.V.J.)

Sugars as the Optimal Biosynthetic Carbon Substrate of Aqueous Life throughout the Universe

NASA Technical Reports Server (NTRS)

Weber, Arthur L.

1999-01-01

Our previous analysis of the energetics of metabolism showed that both the biosynthesis of amino acids and lipids from sugars, and the fermentation of organic substrates, were energetically driven by electron transfer reactions resulting in carbon redox disproportionation (Weber 1997). Redox disproportionation -- the spontaneous (energetically favorable) direction of carbon group transformation in biosynthesis -- is brought about and driven by the energetically downhill transfer of electron pairs from more oxidized carbon groups (with lower half-cell reduction potentials) to more reduced carbon groups (with higher half-cell reduction potentials). In this report, we compare the redox and kinetic properties of carbon groups in order to evaluate the relative biosynthetic capability of organic substrates, and to identify the optimal biosubstrate. This analysis revealed that sugars (monocarbonyl alditols) are the optimal biosynthetic substrate because they contain the maximum number of biosynthetically useful .high energy electrons/carbon atom , while still containing a single carbonyl group needed to kinetically facilitate their conversion to useful biosynthetic intermediates. This conclusion applies to aqueous life throughout the Universe because it is based on invariant aqueous carbon chemistry -- primarily, the universal reduction potentials of carbon groups.

Sugars as the optimal biosynthetic carbon substrate of aqueous life throughout the universe

NASA Technical Reports Server (NTRS)

Weber, A. L.

2000-01-01

Our previous analysis of the energetics of metabolism showed that both the biosynthesis of amino acids and lipids from sugars, and the fermentation of organic substrates, were energetically driven by electron transfer reactions resulting in carbon redox disproportionation (Weber, 1997). Redox disproportionation--the spontaneous (energetically favorable) direction of carbon group transformation in biosynthesis--is brought about and driven by the energetically downhill transfer of electron pairs from more oxidized carbon groups (with lower half-cell reduction potentials) to more reduced carbon groups (with higher half-cell reduction potentials). In this report, we compare the redox and kinetic properties of carbon groups in order to evaluate the relative biosynthetic capability of organic substrates, and to identify the optimal biosubstrate. This analysis revealed that sugars (monocarbonyl alditols) are the optimal biosynthetic substrate because they contain the maximum number of biosynthetically useful high energy electrons/carbon atom while still containing a single carbonyl group needed to kinetically facilitate their conversion to useful biosynthetic intermediates. This conclusion applies to aqueous life throughout the Universe because it is based on invariant aqueous carbon chemistry--primarily, the universal reduction potentials of carbon groups.

Influence of moisture content and temperature on degree of carbonation and the effect on Cu and Cr leaching from incineration bottom ash.

PubMed

Lin, Wenlin Yvonne; Heng, Kim Soon; Sun, Xiaolong; Wang, Jing-Yuan

2015-09-01

This study investigated the influence of moisture content and temperature on the degree of carbonation of municipal solid waste (MSW) incineration bottom ash (IBA) from two different incineration plants in Singapore. The initial rate of carbonation was affected by the nominal moisture content used. Carbonation temperature seemed to play a part in changing the actual moisture content of IBA during carbonation, which in turn affected the degree of carbonation. Results showed that 2h of carbonation was sufficient for the samples to reach a relatively high degree of carbonation that was close to the degree of carbonation observed after 1week of carbonation. Both Cu and Cr leaching also showed significant reduction after only 2h of carbonation. Therefore, the optimum moisture content and temperature were selected based on 2h of carbonation. The optimum moisture content was 15% for both incineration plants while the optimum temperature was different for the two incineration plants, at 35°C and 50°C. The effect on Cu and Cr leaching from IBA after accelerated carbonation was evaluated as a function of carbonation time. Correlation coefficient, Pearson's R, was used to determine the dominant leaching mechanism. The reduction in Cu leaching was found to be contributed by both formation of carbonate mineral and reduction of DOC leaching. On the other hand, Cr leaching seemed to be dominantly controlled by pH. Copyright © 2015 Elsevier Ltd. All rights reserved.

Analysis on carbon dioxide emission reduction during the anaerobic synergetic digestion technology of sludge and kitchen waste: Taking kitchen waste synergetic digestion project in Zhenjiang as an example.

PubMed

Guo, Qia; Dai, Xiaohu

2017-11-01

With the popularization of municipal sewage treatment facilities, the improvement of sewage treatment efficiency and the deepening degree of sewage treatment, the sludge production of sewage plant has been sharply increased. Carbon emission during the process of municipal sewage treatment and disposal has become one of the important sources of greenhouse gases that cause greenhouse effect. How to reduce carbon dioxide emissions during sewage treatment and disposal process is of great significance for reducing air pollution. Kitchen waste and excess sludge, as two important organic wastes, once uses anaerobic synergetic digestion technology in the treatment process can on the one hand, avoid instability of sludge individual anaerobic digestion, improve sludge degradation rate and marsh gas production rate, and on the other hand, help increase the reduction of carbon dioxide emissions to a great extent. The paper uses material balance method, analyzes and calculates the carbon dioxide emissions from kitchen waste and sludge disposed by the anaerobic synergetic digestion technology, compares the anaerobic synergetic digestion technology with traditional sludge sanitary landfill technology and works out the carbon dioxide emission reductions after synergetic digestion. It takes the kitchen waste and sludge synergetic digestion engineering project of Zhenjiang city in Jiangsu province as an example, makes material balance analysis using concrete data and works out the carbon dioxide daily emission reductions. The paper analyzes the actual situation of emission reduction by comparing the data, and found that the synergetic digestion of kitchen waste and sludge can effectively reduce the carbon dioxide emission, and the reduction is obvious especially compared with that of sludge sanitary landfill, which has a certain effect on whether to promote the use of the technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acceptance and Commitment Therapy for chronic pain: A diary study of treatment process in relation to reliable change in disability

PubMed Central

Vowles, Kevin E.; Fink, Brandi C.; Cohen, Lindsey L.

2016-01-01

In chronic pain treatment, a primary goal is reduced disability. It is often assumed that a central process by which disability reduction occurs is pain reduction. Conversely, approaches such as Acceptance and Commitment Therapy (ACT) posit that pain reduction is not necessary for reduced disability. Instead, disability reduction occurs when responses to pain are changed, such that as unsuccessful struggles for pain control decreases and engagement in personally-valued activities increases. Treatment outcome studies have supported ACT’s effectiveness; however, less work has examined how within-treatment patterns of change relate to treatment success or failure (i.e., decreased or sustained disability). The present study, therefore, sought to examine this issue. Specifically, struggles for pain control and engagement in valued activities were recorded weekly in 21 patients who completed a four week interdisciplinary ACT intervention for chronic pain. It was hypothesized that the presence or absence of reliable change in disability at a three month follow-up would be predicted by within treatment patterns of change in the weekly data. At follow-up, 47.6% of patients evidenced reliable disability reduction. The expected pattern of change occurred in 81.0% of patients–specifically, when pain control attempts decreased and engagement in valued activities increased, reliably reduced disability typically occurred, while the absence of this pattern was typically associated with a lack of reliable change. Further, changes in pain intensity, also assessed weekly, were unrelated to reliable change. Overall, these results provide additional support for the ACT model and further suggest some possible requirements for treatment success. PMID:27818931

The Healthy Weight Commitment Foundation Pledge

PubMed Central

Ng, Shu Wen; Popkin, Barry M.

2014-01-01

Context An independent evaluation of the Healthy Weight Commitment Foundation (HWCF) marketplace pledge found that the participating companies met and exceeded their interim 2012 sales reduction pledge. Evidence acquisition This follow-up study conducted in 2013 used purchase data from 2000–2012 among U.S. households with children and compared trends in calorie purchases of HWCF, non-HWCF name brands, and private label (PL) products in the pre-pledge period (2000–2007) and the post-pledge period (2008–2012); controlled for potential effects of concurrent changes in demographic and economic factors, including the Great Recession and food prices; and assessed whether the HWCF marketplace pledge was associated with reductions in consumer packaged goods (CPG) calorie purchases by households with children. Evidence synthesis There has been a significant per capita decline in average daily CPG caloric purchases between 2000 and 2012 among households with children from all brand categories. Based on pre-pledge trends, declines in CPG caloric purchases were already occurring. However, post-pledge reductions in calories purchased from HWCF brands were less than expected, and reductions in calories purchased from non-HWCF name brands and PLs were greater than expected after economic, sociodemographic, and secular factors were accounted for. Conclusions If the 16 HWCF companies had been able to maintain their pre-pledge trajectory, there should have been an additional 42 kcals/capita/day reduction in calories purchased from HWCF products in 2012 among households with children. A lack of change in total CPG calories purchased between 2011 and 2012 calls into question the sustainability of the decline and a need for continued monitoring. PMID:25240968

Telemedicine can make healthcare greener.

PubMed

Yellowlees, Peter M; Chorba, Kathy; Burke Parish, Michelle; Wynn-Jones, Hannah; Nafiz, Najia

2010-03-01

The American healthcare industry is generally lacking environmentally sustainable practices. The environmental impact of healthcare practices in the country has been largely disregarded due to ambivalence, ignorance, and fears of additional costs and regulations. The current practices continue to pollute the environment by requiring large amounts of travel and paperwork by both the patient and the clinician. Telemedicine and health information technology help save time, energy, raw materials (such as paper and plastic), and fuel, thereby lowering the carbon footprint of the health industry. By implementing green practices, for instance, by engaging in carbon credit programs, the health industry could benefit financially as well as reduce its negative impact on the health of our planet. Companies that reduce their carbon emissions by implementing energy-saving practices can sell their carbon credits to companies that emit more carbon than permissible by their legally binding commitment. These carbon profits can then be used for healthcare research or to provide healthcare to the underserved. Alternatively, the savings could be used for green purchasing and to implement other carbon-reducing activities. This report reviews the numerous possible options for the American health industry to become greener and lower its carbon footprint while at the same time becoming more time- and cost efficient.

Microfluidic platform for studying the electrochemical reduction of carbon dioxide

NASA Astrophysics Data System (ADS)

Whipple, Devin Talmage

Diminishing supplies of conventional energy sources and growing concern over greenhouse gas emissions present significant challenges to supplying the world's rapidly increasing demand for energy. The electrochemical reduction of carbon dioxide has the potential to address many of these issues by providing a means of storing electricity in chemical form. Storing electrical energy as chemicals is beneficial for leveling the output of clean, but intermittent renewable energy sources such as wind and solar. Electrical energy stored as chemicals can also be used as carbon neutral fuels for portable applications allowing petroleum derived fuels in the transportation sector to be replaced by more environmentally friendly energy sources. However, to be a viable technology, the electrochemical reduction of carbon dioxide needs to have both high current densities and energetic efficiencies (Chapter 1). Although many researchers have studied the electrochemical reduction of CO2 including parameters such as catalysts, electrolytes and temperature, further investigation is needed to improve the understanding of this process and optimize the performance (Chapter 2). This dissertation reports the development and validation of a microfluidic reactor for the electrochemical reduction of CO2 (Chapter 3). The design uses a flowing liquid electrolyte instead of the typical polymer electrolyte membrane. In addition to other benefits, this flowing electrolyte gives the reactor great flexibility, allowing independent analysis of each electrode and the testing of a wide variety of conditions. In this work, the microfluidic reactor has been used in the following areas: • Comparison of different metal catalysts for the reduction of CO2 to formic acid and carbon monoxide (Chapter 4). • Investigation of the effects of the electrolyte pH on the reduction of CO2 to formic acid and carbon monoxide (Chapter 5). • Study of amine based electrolytes for lowering the overpotentials for CO2 reduction and suppressing undesirable hydrogen evolution (Chapter 6). • Investigation of the effects of reaction temperature on the Faradaic efficiency and current density for CO2 reduction on several catalysts (Chapter 7). These studies demonstrate the utility of this flexible reactor design and provide increased understanding of the electrochemical reduction of CO2 and the critical parameters for optimization of this process.

Reaction engineering for materials processing in space: Reduction of ilmenite by hydrogen and carbon monoxide

NASA Technical Reports Server (NTRS)

Zhao, Y.; Shadman, F.

1991-01-01

Oxygen is a consumable material which needs to be produced continuously in most space missions. Its use for propulsion as well as life support makes oxygen one of the largest volume chemicals to be produced in space. Production of oxygen from lunar materials is of particular interest and is very attractive possibility. The kinetics and mechanism of reduction of ilmenite by carbon monoxide and hydrogen at 800 to 1100 C were investigated. The temporal profiles of conversion for carbon monoxide have a sigmoidal shape and indicate the presence of three different stages (induction, acceleration, and deceleration) during the reduction reaction. The apparent activation energy decreases from 18 kcal/mole at 10 percent conversion to 10 kcal/mole at 50 percent conversion. The reaction is first order with respect to carbon monoxide under the experimental conditions studied. Both SEM and EDX analysis show that the diffusion of Fe product away from the reaction front and through the TiO2 phase, followed by the nucleation and growth of a separate Fe phase are important steps affecting the process kinetics. The results from hydrogen reduction show that the mechanism of ilmenite reduction by hydrogen is similar to that by carbon monoxide. However, the titanium dioxide can be further reduced by hydrogen at 800 to 1000 C. The detailed comparison and theoretical modeling of both reduction processes is presented.

Ni0 encapsulated in N-doped carbon nanotubes for catalytic reduction of highly toxic hexavalent chromium

NASA Astrophysics Data System (ADS)

Yao, Yunjin; Zhang, Jie; Chen, Hao; Yu, Maojing; Gao, Mengxue; Hu, Yi; Wang, Shaobin

2018-05-01

N-doped carbon nanotubes encapsulating Ni0 nanoparticles (Ni@N-C) were fabricated via thermal reduction of dicyandiamide and NiCl2·6H2O, and used to remove CrVI in polluted water. The resultant products present an excellent catalytic activity for CrVI reduction using formic acid under relatively mild conditions. The CrVI reduction efficiency of Ni@N-C was significantly affected by the preparation conditions including the mass of nickel salt and synthesis temperatures. The impacts of several reaction parameters, such as initial concentrations of CrVI and formic acid, solution pH and temperatures, as well as inorganic anions in solution on CrVI reduction efficiency were also evaluated in view of scalable industrial applications. Owing to the synergistic effects amongst tubes-coated Ni0, doped nitrogen, oxygen containing groups, and the configuration of carbon nanotubes, Ni@N-C catalysts exhibit excellent catalytic activity and recyclable capability for CrVI reduction. Carbon shell can efficiently protect inner Ni0 core and N species from corrosion and subsequent leaching, while Ni0 endows the Ni@N-C catalysts with ferromagnetism, so that the composites can be easily separated via a permanent magnet. This study opens up an avenue for design of N-doped carbon nanotubes encapsulating Ni0 nanoparticles with high CrVI removal efficiency and magnetic recyclability as low-cost catalysts for industrial applications.

Effects of job rotation and role stress among nurses on job satisfaction and organizational commitment

PubMed Central

Ho, Wen-Hsien; Chang, Ching Sheng; Shih, Ying-Ling; Liang, Rong-Da

2009-01-01

Background The motivation for this study was to investigate how role stress among nurses could affect their job satisfaction and organizational commitment, and whether the job rotation system might encourage nurses to understand, relate to and share the vision of the organization, consequently increasing their job satisfaction and stimulating them to willingly remain in their jobs and commit themselves to the organization. Despite the fact that there have been plenty of studies on job satisfaction, none was specifically addressed to integrate the relational model of job rotation, role stress, job satisfaction, and organizational commitment among nurses. Methods With top managerial hospital administration's consent, questionnaires were only distributed to those nurses who had had job rotation experience. 650 copies of the questionnaire in two large and influential hospitals in southern Taiwan were distributed, among which 532 valid copies were retrieved with a response rate of 81.8%. Finally, the SPSS 11.0 and LISREL 8.54 (Linear Structural Relationship Model) statistical software packages were used for data analysis and processing. Results According to the nurses' views, the findings are as follows: (1) job rotation among nurses could have an effect on their job satisfaction; (2) job rotation could have an effect on organizational commitment; (3) job satisfaction could have a positive effect on organizational commitment; (4) role stress among nurses could have a negative effect on their job satisfaction; and (5) role stress could have a negative effect on their organizational commitment. Conclusion As a practical and excellent strategy for manpower utilization, a hospital could promote the benefits of job rotation to both individuals and the hospital while implementing job rotation periodically and fairly. And when a medical organization attempts to enhance nurses' commitment to the organization, the findings suggest that reduction of role ambiguity in role stress has the best effect on enhancing nurses' organizational commitment. The ultimate goal is to increase nurses' job satisfaction and encourage them to stay in their career. This would avoid the vicious circle of high turnover, which is wasteful of the organization's valuable human resources. PMID:19138390

Effects of job rotation and role stress among nurses on job satisfaction and organizational commitment.

PubMed

Ho, Wen-Hsien; Chang, Ching Sheng; Shih, Ying-Ling; Liang, Rong-Da

2009-01-12

The motivation for this study was to investigate how role stress among nurses could affect their job satisfaction and organizational commitment, and whether the job rotation system might encourage nurses to understand, relate to and share the vision of the organization, consequently increasing their job satisfaction and stimulating them to willingly remain in their jobs and commit themselves to the organization. Despite the fact that there have been plenty of studies on job satisfaction, none was specifically addressed to integrate the relational model of job rotation, role stress, job satisfaction, and organizational commitment among nurses. With top managerial hospital administration's consent, questionnaires were only distributed to those nurses who had had job rotation experience. 650 copies of the questionnaire in two large and influential hospitals in southern Taiwan were distributed, among which 532 valid copies were retrieved with a response rate of 81.8%. Finally, the SPSS 11.0 and LISREL 8.54 (Linear Structural Relationship Model) statistical software packages were used for data analysis and processing. According to the nurses' views, the findings are as follows: (1) job rotation among nurses could have an effect on their job satisfaction; (2) job rotation could have an effect on organizational commitment; (3) job satisfaction could have a positive effect on organizational commitment; (4) role stress among nurses could have a negative effect on their job satisfaction; and (5) role stress could have a negative effect on their organizational commitment. As a practical and excellent strategy for manpower utilization, a hospital could promote the benefits of job rotation to both individuals and the hospital while implementing job rotation periodically and fairly. And when a medical organization attempts to enhance nurses' commitment to the organization, the findings suggest that reduction of role ambiguity in role stress has the best effect on enhancing nurses' organizational commitment. The ultimate goal is to increase nurses' job satisfaction and encourage them to stay in their career. This would avoid the vicious circle of high turnover, which is wasteful of the organization's valuable human resources.

77 FR 7517 - Definitions and Abbreviations

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-13

... Paperwork Reduction Act of 1995 (44 U.S.C. Chapter 35). E-Government Act Compliance Rural Development is committed to complying with the E-Government Act, to promote the use of the Internet and other information... following methods: Federal eRulemaking Portal: http://www.regulations.gov . Follow the instructions for...

76 FR 47055 - Emergency Restoration Plan (ERP)

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-04

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Detecting Salmonella Enteritidis in Laying Hens and Eggs after Experimental Infection at Different Oral Dose Levels

USDA-ARS?s Scientific Manuscript database

The attribution of human illness to eggs contaminated with Salmonella Enteritidis has led to substantial commitments of resources (by both government and industry) to risk reduction and testing programs in egg-laying flocks. Cost-effective application of testing requires a thorough understanding of ...

Salmonella Enteritidis deposition in eggs after experimental infection of laying hens with different oral doses

USDA-ARS?s Scientific Manuscript database

The continuing attribution of human Salmonella Enteritidis (SE) infections to internally contaminated eggs has necessitated the commitment of substantial public and private resources to SE testing and control programs in commercial laying flocks. Cost-effective risk reduction requires a detailed and...

Fructan reduction by downregulation of 1-SST in guayule

USDA-ARS?s Scientific Manuscript database

The natural rubber producing plant Parthenium argentatum (guayule) stores carbohydrates mainly in the form of fructans, which are synthesized and stored in the same tissues at the same time as the rubber polymer. The first committed step to fructan synthesis is catalyzed by sucrose:sucrose-1-fructos...

76 FR 22896 - Agency Information Collection Activities: Proposed Collection; Submission for OMB Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-25

... comments to EEOC, you may submit comments and attachments electronically at http://www.regulations.gov... being committed and to produce reports from the data. The EEOC issued regulations, Title 29, Chapter XIV... accordance with the Paperwork Reduction Act, the Equal Employment Opportunity Commission (EEOC or Commission...

When will we be committed to crossing 1.5 and 2 °C temperature thresholds?

NASA Astrophysics Data System (ADS)

Armour, K.; Proistosescu, C.; Roe, G.; Huybers, P. J.

2017-12-01

The zero-emissions climate commitment is a key metric for science and policy. It is the future warming we face given only to-date emissions, independent of future human influence on climate. Following a cessation of emissions, future global temperature change depends on (i) the atmospheric lifetimes of aerosols and greenhouse gases (GHGs), and (ii) the physical climate response to radiative forcing (Armour and Roe 2011). The cooling effect of aerosols diminishes within weeks; GHG concentrations get drawn down on timescales ranging from months to millennia; and ocean heat uptake diminishes as climate equilibrates with the residual CO2 forcing. Whether global temperature increases, stays stable, or declines following emission cessation depends on these competing factors. There is substantial uncertainty in the zero-emissions commitment due to a combination of (i) correlated uncertainties in aerosol radiative forcing and climate sensitivity, (ii) uncertainty in the atmospheric lifetime of CO2, and (iii) uncertainty in how climate sensitivity will evolve in the future. Here we quantify climate commitment in a Bayesian framework of an idealized model constrained by observations of global warming and energy imbalance, combined with estimates of global radiative forcing. At present, our committed warming is 1.2°C (median), with a 25% chance that it already exceeds 1.5°C and a 5% chance that it exceeds 2°C; the range comes primarily from uncertainty in the degree to which aerosols currently mask GHG forcing. We further quantify how climate commitment, and its uncertainty, changes with emissions scenario and over time. Under high emissions (RCP8.5), we will reach a >50% risk of a 2°C zero-emission climate commitment by the year 2035, about two decades before that temperature would be reached if emissions continued unabated. Committed warming is substantially reduced for lower-emissions scenarios, depending on the mix of aerosol and GHG mitigation. For the next few decades the primary uncertainty in climate commitment comes from correlated uncertainties in aerosol forcing and climate sensitivity; later in the century it comes from uncertainties in the carbon cycle (setting the lifetime and residual concentration of CO2) and in how climate sensitivity changes over time.

Electrochemical process for the preparation of nitrogen fertilizers

DOEpatents

Aulich, Ted R [Grand Forks, ND; Olson, Edwin S [Grand Forks, ND; Jiang, Junhua [Grand Forks, ND

2012-04-10

The present invention provides methods and apparatus for the preparation of nitrogen fertilizers including ammonium nitrate, urea, urea-ammonium nitrate, and/or ammonia, at low temperature and pressure, preferably at ambient temperature and pressure, utilizing a source of carbon, a source of nitrogen, and/or a source of hydrogen or hydrogen equivalent. Implementing an electrolyte serving as ionic charge carrier, (1) ammonium nitrate is produced via the reduction of a nitrogen source at the cathode and the oxidation of a nitrogen source at the anode; (2) urea or its isomers are produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source; (3) ammonia is produced via the reduction of nitrogen source at the cathode and the oxidation of a hydrogen source or a hydrogen equivalent such as carbon monoxide or a mixture of carbon monoxide and hydrogen at the anode; and (4) urea-ammonium nitrate is produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source, and anodic oxidation of a nitrogen source. The electrolyte can be aqueous, non-aqueous, or solid.

Multi-walled Carbon Nanotubes Reduce Toxicity of Diphenhydramine to Ceriodaphnia dubia in Water and Sediment Exposures.

PubMed

Myer, Mark H; Black, Marsha C

2017-09-01

Multi-walled carbon nanotubes are adsorptive materials that have potential for remediation of organic contaminants in water. Sediment elutriate exposures were undertaken with Ceriodaphnia dubia to compare the toxic effects of diphenhydramine in the presence and absence of sediment and multi-walled carbon nanotubes. In both sediment and solution-only treatments, addition of 0.318 mg/g of carbon nanotubes significantly decreased 48-h mortality relative to control, with a 78.7%-90.1% reduction in treatments with nanotube-amended sediment and 40.7%-53.3% reduction in nanotube-amended water exposures. The greatest degree of relative mortality reduction occurred in sediments containing higher levels of natural organic matter, indicating a potential additive effect.

Carbon Monoxide as an Electron Donor for the Biological Reduction of Sulphate

PubMed Central

Parshina, Sofiya N.; Sipma, Jan; Henstra, Anne Meint; Stams, Alfons J. M.

2010-01-01

Several strains of Gram-negative and Gram-positive sulphate-reducing bacteria (SRB) are able to use carbon monoxide (CO) as a carbon source and electron donor for biological sulphate reduction. These strains exhibit variable resistance to CO toxicity. The most resistant SRB can grow and use CO as an electron donor at concentrations up to 100%, whereas others are already severely inhibited at CO concentrations as low as 1-2%. Here, the utilization, inhibition characteristics, and enzymology of CO metabolism as well as the current state of genomics of CO-oxidizing SRB are reviewed. Carboxydotrophic sulphate-reducing bacteria can be applied for biological sulphate reduction with synthesis gas (a mixture of hydrogen and carbon monoxide) as an electron donor. PMID:20628586

Carbon-neutral energy cycles using alcohols.

PubMed

Fukushima, Takashi; Kitano, Sho; Hata, Shinichi; Yamauchi, Miho

2018-01-01

We demonstrated carbon-neutral (CN) energy circulation using glycolic acid ( GC )/oxalic acid ( OX ) redox couple. Here, we report fundamental studies on both catalyst search for power generation process, i.e. GC oxidation, and elemental steps for fuel generation process, i.e. OX reduction, in CN cycle. The catalytic activity test on various transition metals revealed that Rh, Pd, Ir, and Pt have preferable features as a catalyst for electrochemical oxidation of GC . A carbon-supported Pt catalyst in alkaline conditions exhibited higher activity, durability, and product selectivity for electrooxidation of GC rather than those in acidic media. The kinetic study on OX reduction clearly indicated that OX reduction undergoes successive two-electron reductions to form GC . Furthermore, application of TiO 2 catalysts with large specific area for electrochemical reduction of OX facilitates the selective formation of GC .

Carbon-neutral energy cycles using alcohols

PubMed Central

Fukushima, Takashi; Kitano, Sho; Hata, Shinichi; Yamauchi, Miho

2018-01-01

Abstract We demonstrated carbon-neutral (CN) energy circulation using glycolic acid (GC)/oxalic acid (OX) redox couple. Here, we report fundamental studies on both catalyst search for power generation process, i.e. GC oxidation, and elemental steps for fuel generation process, i.e. OX reduction, in CN cycle. The catalytic activity test on various transition metals revealed that Rh, Pd, Ir, and Pt have preferable features as a catalyst for electrochemical oxidation of GC. A carbon-supported Pt catalyst in alkaline conditions exhibited higher activity, durability, and product selectivity for electrooxidation of GC rather than those in acidic media. The kinetic study on OX reduction clearly indicated that OX reduction undergoes successive two-electron reductions to form GC. Furthermore, application of TiO2 catalysts with large specific area for electrochemical reduction of OX facilitates the selective formation of GC. PMID:29511392

Carbon-constrained health care enterprise.

PubMed

Gell, Michael

2010-02-01

The health economy is a significant part of a national economy accounting typically for about 8% of GDP spent. As national economies respond to the dual challenges of severe economic turbulence on the global scale and climate change mitigation, the health economy is coming under increasing pressure to respond. Indications for sharp reductions in budgets and reductions in greenhouse gas emissions, such as carbon dioxide, are widespread. In this paper an analysis is undertaken of the diverse forces acting on a typical health care enterprise. The forces, both economic and carbon related, are investigated in terms of their effects through the enterprise and across its boundaries on the supply, demand and waste sides. The overall aim is to show how the enterprise and whole supply chains may flip synchronously into a low-carbon evolutionary pathway. By illustrating how different elements of the health care enterprise may respond to these developments, diverse opportunities for cost reduction, carbon reduction and product (goods and services) development are identified. These opportunities involve a variety of waste reduction and energy and materials conservation measures as well as new ways of collaborating with other enterprises going through similar transformations. The overall objective is to show that the carbon-constrained health care enterprise and the low-carbon health economy in which it sits may broaden its role in the coming decades to include a degree of responsibility for the health of the environment. This broader role is likely to supplement and entangle with the traditional role of the health economy, currently focused narrowly on human health, and lead to extensive organisational transformation, and infrastructure and product developments.

The multimillennial sea-level commitment of global warming.

PubMed

Levermann, Anders; Clark, Peter U; Marzeion, Ben; Milne, Glenn A; Pollard, David; Radic, Valentina; Robinson, Alexander

2013-08-20

Global mean sea level has been steadily rising over the last century, is projected to increase by the end of this century, and will continue to rise beyond the year 2100 unless the current global mean temperature trend is reversed. Inertia in the climate and global carbon system, however, causes the global mean temperature to decline slowly even after greenhouse gas emissions have ceased, raising the question of how much sea-level commitment is expected for different levels of global mean temperature increase above preindustrial levels. Although sea-level rise over the last century has been dominated by ocean warming and loss of glaciers, the sensitivity suggested from records of past sea levels indicates important contributions should also be expected from the Greenland and Antarctic Ice Sheets. Uncertainties in the paleo-reconstructions, however, necessitate additional strategies to better constrain the sea-level commitment. Here we combine paleo-evidence with simulations from physical models to estimate the future sea-level commitment on a multimillennial time scale and compute associated regional sea-level patterns. Oceanic thermal expansion and the Antarctic Ice Sheet contribute quasi-linearly, with 0.4 m °C(-1) and 1.2 m °C(-1) of warming, respectively. The saturation of the contribution from glaciers is overcompensated by the nonlinear response of the Greenland Ice Sheet. As a consequence we are committed to a sea-level rise of approximately 2.3 m °C(-1) within the next 2,000 y. Considering the lifetime of anthropogenic greenhouse gases, this imposes the need for fundamental adaptation strategies on multicentennial time scales.

The multimillennial sea-level commitment of global warming

PubMed Central

Levermann, Anders; Clark, Peter U.; Marzeion, Ben; Milne, Glenn A.; Pollard, David; Radic, Valentina; Robinson, Alexander

2013-01-01

Global mean sea level has been steadily rising over the last century, is projected to increase by the end of this century, and will continue to rise beyond the year 2100 unless the current global mean temperature trend is reversed. Inertia in the climate and global carbon system, however, causes the global mean temperature to decline slowly even after greenhouse gas emissions have ceased, raising the question of how much sea-level commitment is expected for different levels of global mean temperature increase above preindustrial levels. Although sea-level rise over the last century has been dominated by ocean warming and loss of glaciers, the sensitivity suggested from records of past sea levels indicates important contributions should also be expected from the Greenland and Antarctic Ice Sheets. Uncertainties in the paleo-reconstructions, however, necessitate additional strategies to better constrain the sea-level commitment. Here we combine paleo-evidence with simulations from physical models to estimate the future sea-level commitment on a multimillennial time scale and compute associated regional sea-level patterns. Oceanic thermal expansion and the Antarctic Ice Sheet contribute quasi-linearly, with 0.4 m °C−1 and 1.2 m °C−1 of warming, respectively. The saturation of the contribution from glaciers is overcompensated by the nonlinear response of the Greenland Ice Sheet. As a consequence we are committed to a sea-level rise of approximately 2.3 m °C−1 within the next 2,000 y. Considering the lifetime of anthropogenic greenhouse gases, this imposes the need for fundamental adaptation strategies on multicentennial time scales. PMID:23858443

Deployment, Design, and Commercialization of Carbon-Negative Energy Systems

NASA Astrophysics Data System (ADS)

Sanchez, Daniel Lucio

Climate change mitigation requires gigaton-scale carbon dioxide removal technologies, yet few examples exist beyond niche markets. This dissertation informs large-scale implementation of bioenergy with carbon capture and sequestration (BECCS), a carbon-negative energy technology. It builds on existing literature with a novel focus on deployment, design, commercialization, and communication of BECCS. BECCS, combined with aggressive renewable deployment and fossil emission reductions, can enable a carbon-negative power system in Western North America by 2050, with up to 145% emissions reduction from 1990 levels. BECCS complements other sources of renewable energy, and can be deployed in a manner consistent with regional policies and design considerations. The amount of biomass resource available limits the level of fossil CO2 emissions that can still satisfy carbon emissions caps. Offsets produced by BECCS are more valuable to the power system than the electricity it provides. Implied costs of carbon for BECCS are relatively low ( 75/ton CO2 at scale) for a capital-intensive technology. Optimal scales for BECCS are an order of magnitude larger than proposed scales found in existing literature. Deviations from optimal scaled size have little effect on overall systems costs - suggesting that other factors, including regulatory, political, or logistical considerations, may ultimately have a greater influence on plant size than the techno-economic factors considered. The flexibility of thermochemical conversion enables a viable transition pathway for firms, utilities and governments to achieve net-negative CO 2 emissions in production of electricity and fuels given increasingly stringent climate policy. Primary research, development (R&D), and deployment needs are in large-scale biomass logistics, gasification, gas cleaning, and geological CO2 storage. R&D programs, subsidies, and policy that recognize co-conversion processes can support this pathway to commercialization. Here, firms can embrace a gradual transition pathway to deep decarbonization, limiting economic dislocation and increasing transfer of knowledge between the fossil and renewable sectors. Global cumulative capital investment needs for BECCS through 2050 are over 1.9 trillion (2015$, 4% real interest rate) for scenarios likely to limit global warming to 2 °C. This scenario envisions deployment of as much as 24 GW/yr of BECCS by 2040 in the electricity sector. To achieve theses rates of deployment within 15-20 years, governments and firms must commit to research, development, and deployment on an unprecedented scale. Three primary issues complicate emissions accounting for BECCS: cross-sector CO2 accounting, regrowth, and timing. Switchgrass integration decreases lifecycle greenhouse gas impacts of co-conversion systems with CCS, across a wide range of land-use change scenarios. Risks at commercial scale include adverse effects on food security, land conservation, social equity, and biodiversity, as well as competition for water resources. This dissertation argues for an iterative risk management approach to BECCS sustainability, with standards being updated as more knowledge is gained through deployment. Sustainability impacts and public opposition to BECCS may be reduced with transparent measurement and communication. Commercial-scale deployment is dependent on the coordination of a wide range of actors, many with different incentives and worldviews. Despite this problem, this dissertation challenges governments, industry incumbents, and emerging players to research, support, and deploy BECCS.

Synthesis of reduced carbon nitride at the reduction by hydroquinone of water-soluble carbon nitride oxide (g-C3N4)O

NASA Astrophysics Data System (ADS)

Kharlamov, Alexey; Bondarenko, Marina; Kharlamova, Ganna; Fomenko, Veniamin

2016-09-01

For the first time at the reduction by hydroquinone of water-soluble carbon nitride oxide (g-C3N4)O reduced carbon nitride (or reduced multi-layer azagraphene) is obtained. It is differed from usually synthesized carbon nitride by a significantly large (on 0.09 nm) interplanar distance is. At the same time, the chemical bonds between atoms in a heteroatomic plane of reduced carbon nitride correspond to the bonds in a synthesized g-C3N4. The samples of water-soluble carbon nitride oxide were synthesized under the special reactionary conditions of a pyrolysis of melamine and urea. We believe that reduced carbon nitride consists of weakly connected carbon-nitrogen monosheets (azagraphene sheets) as well as reduced (from graphene oxide) graphene contains weakly connected graphene sheets.

In situ spectroscopic monitoring of CO2 reduction at copper oxide electrode.

PubMed

Wang, Liying; Gupta, Kalyani; Goodall, Josephine B M; Darr, Jawwad A; Holt, Katherine B

2017-04-28

Copper oxide modified electrodes were investigated as a function of applied electrode potential using in situ infrared spectroscopy and ex situ Raman and X-ray photoelectron spectroscopy. In deoxygenated KHCO 3 electrolyte bicarbonate and carbonate species were found to adsorb to the electrode during reduction and the CuO was reduced to Cu(i) or Cu(0) species. Carbonate was incorporated into the structure and the CuO starting material was not regenerated on cycling to positive potentials. In contrast, in CO 2 saturated KHCO 3 solution, surface adsorption of bicarbonate and carbonate was not observed and adsorption of a carbonato-species was observed with in situ infrared spectroscopy. This species is believed to be activated, bent CO 2 . On cycling to negative potentials, larger reduction currents were observed in the presence of CO 2 ; however, less of the charge could be attributed to the reduction of CuO. In the presence of CO 2 CuO underwent reduction to Cu 2 O and potentially Cu, with no incorporation of carbonate. Under these conditions the CuO starting material could be regenerated by cycling to positive potentials.

ABIOTIC REDUCTIVE DECHLORINATION OF CARBON TETRACHLORIDE AND HEXACHLOROETHANE BY ENVIRONMENTAL REDUCTANTS

EPA Science Inventory

The transformation rates of hexachloroethane (HCA) and carbon tetrachloride (CTET) have been measured in model systems representing the ground water environment and in slurries of fractionated Borden aquifer material. his report summarizes research conducted to identify the envir...

Electrochemical reduction of nalidixic acid at glassy carbon electrode modified with multi-walled carbon nanotubes.

PubMed

Patiño, Yolanda; Pilehvar, Sanaz; Díaz, Eva; Ordóñez, Salvador; De Wael, Karolien

2017-02-05

The aqueous phase electrochemical degradation of nalidixic acid (NAL) is studied in this work, using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) as instrumental techniques. The promotional effect of multi-walled carbon nanotubes (MWCNT) on the performance of glassy carbon electrodes is demonstrated, being observed that these materials catalyze the NAL reduction. The effect of surface functional groups on MWCNT -MWCNT-COOH and MWCNT-NH 2 -was also studied. The modification of glassy carbon electrode (GCE) with MWCNT leads to an improved performance for NAL reduction following the order of MWCNT>MWCNT-NH 2 >MWCNT-COOH. The best behavior at MWCNT-GCE is mainly due to both the increased electrode active area and the enhanced MWCNT adsorption properties. The NAL degradation was carried out under optimal conditions (pH=5.0, deposition time=20s and volume of MWCNT=10μL) using MWCNT-GCE obtaining an irreversible reduction of NAL to less toxic products. Paramaters as the number of DPV cycles and the volume/area (V/A) ratio were optimized for maximize pollutant degradation. It was observed that after 15 DPV scans and V/A=8, a complete reduction was obtained, obtaining two sub-products identified by liquid chromatography-mass spectrometry (LC-MS). Copyright © 2016 Elsevier B.V. All rights reserved.

Supramolecular Porphyrin Cages Assembled at Molecular–Materials Interfaces for Electrocatalytic CO Reduction

PubMed Central

2017-01-01

Conversion of carbon monoxide (CO), a major one-carbon product of carbon dioxide (CO2) reduction, into value-added multicarbon species is a challenge to addressing global energy demands and climate change. Here we report a modular synthetic approach for aqueous electrochemical CO reduction to carbon–carbon coupled products via self-assembly of supramolecular cages at molecular–materials interfaces. Heterobimetallic cavities formed by face-to-face coordination of thiol-terminated metalloporphyrins to copper electrodes through varying organic struts convert CO to C2 products with high faradaic efficiency (FE = 83% total with 57% to ethanol) and current density (1.34 mA/cm2) at a potential of −0.40 V vs RHE. The cage-functionalized electrodes offer an order of magnitude improvement in both selectivity and activity for electrocatalytic carbon fixation compared to parent copper surfaces or copper functionalized with porphyrins in an edge-on orientation. PMID:28979945

Preparation of Pt Nanocatalyst on Carbon Materials via a Reduction Reaction of a Pt Precursor in a Drying Process.

PubMed

Lee, Jae-Young; Lee, Woo-Kum; Rim, Hyung-Ryul; Joung, Gyu-Bum; Weidner, John W; Lee, Hong-Ki

2016-06-01

Platinum (Pt) nanocatalyst for a proton-exchange membrane fuel cell (PEMFC) was prepared on a carbon black particle or a graphite particle coated with a nafion polymer via a reduction of platinum(II) bis(acetylacetonate) denoted as Pt(acac)2 as a Pt precursor in a drying process. Sublimed Pt(acac)2 adsorbed on the nafion-coated carbon materials was reduced to Pt nanoparticles in a glass reactor at 180 degrees C of N2 atmosphere. The morphology of Pt nanoparticles on carbon materials was observed by scanning electron microscopy (SEM) and the distribution of Pt nanoparticles was done by transmission electron microscopy (TEM). The particle size was estimated by analyzing the TEM image using an image analyzer. It was found that nano-sized Pt particles were deposited on the surface of carbon materials, and the number density and the average particle size increased with increasing reduction time.

The Impact of Technological Progress in the Energy Sector on Carbon Emissions: An Empirical Analysis from China

PubMed Central

Jin, Lei; Duan, Keran; Shi, Chunming; Ju, Xianwei

2017-01-01

This paper investigates the relationship between technological progress in the energy sector and carbon emissions based on the Environment Kuznets Curve (EKC) and data from China during the period of 1995–2012. Our study confirms that the situation in China conforms to the EKC hypothesis and presents the inverted U-curve relationship between per capita income and carbon emissions. Furthermore, the inflection point will be reached in at least five years. Then, we use research and development (R & D) investment in the energy industry as the quantitative indicator of its technological progress to test its impact on carbon emissions. Our results show that technological progress in the energy sector contributes to a reduction in carbon emissions with hysteresis. Furthermore, our results show that energy efficiency improvements are also helpful in reducing carbon emissions. However, climate policy and change in industrial structure increase carbon emissions to some extent. Our conclusion demonstrates that currently, China is not achieving economic growth and pollution reduction simultaneously. To further achieve the goal of carbon reduction, the government should increase investment in the energy industry research and improve energy efficiency. PMID:29207562

The Impact of Technological Progress in the Energy Sector on Carbon Emissions: An Empirical Analysis from China.

PubMed

Jin, Lei; Duan, Keran; Shi, Chunming; Ju, Xianwei

2017-12-04

This paper investigates the relationship between technological progress in the energy sector and carbon emissions based on the Environment Kuznets Curve (EKC) and data from China during the period of 1995-2012. Our study confirms that the situation in China conforms to the EKC hypothesis and presents the inverted U-curve relationship between per capita income and carbon emissions. Furthermore, the inflection point will be reached in at least five years. Then, we use research and development (R & D) investment in the energy industry as the quantitative indicator of its technological progress to test its impact on carbon emissions. Our results show that technological progress in the energy sector contributes to a reduction in carbon emissions with hysteresis. Furthermore, our results show that energy efficiency improvements are also helpful in reducing carbon emissions. However, climate policy and change in industrial structure increase carbon emissions to some extent. Our conclusion demonstrates that currently, China is not achieving economic growth and pollution reduction simultaneously. To further achieve the goal of carbon reduction, the government should increase investment in the energy industry research and improve energy efficiency.

Photoassisted carbon dioxide reduction and formation of twoand three-carbon compounds. [prebiological photosynthesis

NASA Technical Reports Server (NTRS)

Halmann, M.; Aurian-Blajeni, B.; Bloch, S.

1981-01-01

The photoassisted reduction of aqueous carbon dioxide in the presence of naturally occurring minerals is investigated as a possible abiotic precursor of photosynthesis. Aqueous carbon dioxide saturated suspensions or surfaces of the minerals nontronite, bentonite, anatase, wolframite, molybdenite, minium, cinnabar and hematite were irradiated with high-pressure mercury lamps or sunlight. Chemical analyses reveal the production of formic acid, formaldehyde, methanol and methane, and the two and three-carbon compounds glyoxal (CHOCHO) and malonaldehyde (CH2(CHO)2). It is suggested that such photosynthetic reactions with visible light in the presence of semiconducting minerals may provide models for prebiological carbon and nitrogen fixation in both oxidized and reduced atmospheres.

Country actions to meet UN commitments on non-communicable diseases: a stepwise approach.

PubMed

Bonita, Ruth; Magnusson, Roger; Bovet, Pascal; Zhao, Dong; Malta, Deborah C; Geneau, Robert; Suh, Il; Thankappan, Kavumpurathu Raman; McKee, Martin; Hospedales, James; de Courten, Maximilian; Capewell, Simon; Beaglehole, Robert

2013-02-16

Strong leadership from heads of state is needed to meet national commitments to the UN political declaration on non-communicable diseases (NCDs) and to achieve the goal of a 25% reduction in premature NCD mortality by 2025 (the 25 by 25 goal). A simple, phased, national response to the political declaration is suggested, with three key steps: planning, implementation, and accountability. Planning entails mobilisation of a multisectoral response to develop and support the national action plan, and to build human, financial, and regulatory capacity for change. Implementation of a few priority and feasible cost-effective interventions for the prevention and treatment of NCDs will achieve the 25 by 25 goal and will need only few additional financial resources. Accountability incorporates three dimensions: monitoring of progress, reviewing of progress, and appropriate responses to accelerate progress. A national NCD commission or equivalent, which is independent of government, is needed to ensure that all relevant stakeholders are held accountable for the UN commitments to NCDs. Copyright © 2013 Elsevier Ltd. All rights reserved.

Threshold amounts of organic carbon needed to initiate reductive dechlorination in groundwater systems

USGS Publications Warehouse

Chapelle, Francis H.; Thomas, Lashun K.; Bradley, Paul M.; Rectanus, Heather V.; Widdowson, Mark A.

2012-01-01

Aquifer sediment and groundwater chemistry data from 15 Department of Defense facilities located throughout the United States were collected and analyzed with the goal of estimating the amount of natural organic carbon needed to initiate reductive dechlorination in groundwater systems. Aquifer sediments were analyzed for hydroxylamine and NaOH-extractable organic carbon, yielding a probable underestimate of potentially bioavailable organic carbon (PBOC). Aquifer sediments were also analyzed for total organic carbon (TOC) using an elemental combustion analyzer, yielding a probable overestimate of bioavailable carbon. Concentrations of PBOC correlated linearly with TOC with a slope near one. However, concentrations of PBOC were consistently five to ten times lower than TOC. When mean concentrations of dissolved oxygen observed at each site were plotted versus PBOC, it showed that anoxic conditions were initiated at approximately 200 mg/kg of PBOC. Similarly, the accumulation of reductive dechlorination daughter products relative to parent compounds increased at a PBOC concentration of approximately 200 mg/kg. Concentrations of total hydrolysable amino acids (THAA) in sediments also increased at approximately 200 mg/kg, and bioassays showed that sediment CO2 production correlated positively with THAA. The results of this study provide an estimate for threshold amounts of bioavailable carbon present in aquifer sediments (approximately 200 mg/kg of PBOC; approximately 1,000 to 2,000 mg/kg of TOC) needed to support reductive dechlorination in groundwater systems.

Deep-convection events foster carbonate ion reduction in deep coral reefs

NASA Astrophysics Data System (ADS)

Perez, Fiz F.; Fontela, Marcos; Garcia-Ibañez, Maribel I.; Lherminier, Pascale; Zunino, Patricia; de la Paz, Mercedes; Padín, Xose A.; Alonso-Pérez, Fernando; Velo, Anton; Guallart, Elisa F.; Mercier, Herle

2017-04-01

Since millennial times, water mass circulation and deep-convection events have been transforming warm upper waters at high latitudes into cold and well-oxygenated deep waters. These processes have filled the deep North Atlantic Ocean with waters moderately saturated in calcium carbonate, thus promoting the growth of stony corals, which are hotspots of biodiversity. During the Anthropocene, the meridional circulation has been conveying cumulative amounts of more acidified waters with lower calcium carbonate saturation levels due to the incorporation of anthropogenic carbon dioxide, with very harsh conditions for deep cold-water corals projected by 2100. We evaluate the diminution of calcium carbonate saturation levels (aragonite form) due to the increase in anthropogenic carbon dioxide during the last two decades (2002-2016). We observe a strong decrease in the aragonite saturation levels concomitant with the reduction in the volume transport of aragonite-saturated waters. We estimate a 30-35% reduction in the transport of ion carbonate excess over the saturation levels with respect to the natural carbon cycle for the period 2002-2016. This reduction is associated with an increase in the downward transport of hydrogen ions. We also observe a heaving of the aragonite saturation horizons during the last 25 years, which is estimated at 6 m year-1 for the deep waters and 12-14 m year-1 for the intermediated waters. The harsh winters of 2015 and 2016 have fostered the fast addition of more acidified water into the lower layers of the North Atlantic through deep-convection events. In the future scenario of 2oC warming, the anthropogenic carbon dioxide in the water column would be double than today and the associated transport of hydrogen ions towards the bottom water would reduce the aragonite saturation levels to 60-80% with respect to preindustrial levels. This reduction in the aragonite saturation levels would suppose a strong diminution of the North Atlantic habitats where stony corals will be able to inhabit.

Metal/Carbon Hybrid Nanostructures Produced from Plasma-Enhanced Chemical Vapor Deposition over Nafion-Supported Electrochemically Deposited Cobalt Nanoparticles

PubMed Central

Achour, Amine; Saeed, Khalid; Djouadi, Mohamed Abdou

2018-01-01

In this work, we report development of hybrid nanostructures of metal nanoparticles (NP) and carbon nanostructures with strong potential for catalysis, sensing, and energy applications. First, the etched silicon wafer substrates were passivated for subsequent electrochemical (EC) processing through grafting of nitro phenyl groups using para-nitrobenzene diazonium (PNBT). The X-ray photoelectron spectroscope (XPS) and atomic force microscope (AFM) studies confirmed presence of few layers. Cobalt-based nanoparticles were produced over dip or spin coated Nafion films under different EC reduction conditions, namely CoSO4 salt concentration (0.1 M, 1 mM), reduction time (5, 20 s), and indirect or direct EC reduction route. Extensive AFM examination revealed NP formation with different attributes (size, distribution) depending on electrochemistry conditions. While relatively large NP with >100 nm size and bimodal distribution were obtained after 20 s EC reduction in H3BO3 following Co2+ ion uptake, ultrafine NP (<10 nm) could be produced from EC reduction in CoSO4 and H3BO3 mixed solution with some tendency to form oxides. Different carbon nanostructures including few-walled or multiwalled carbon nanotubes (CNT) and carbon nanosheets were grown in a C2H2/NH3 plasma using the plasma-enhanced chemical vapor deposition technique. The devised processing routes enable size controlled synthesis of cobalt nanoparticles and metal/carbon hybrid nanostructures with unique microstructural features. PMID:29702583

Carbon and energy saving markets in compressed air

NASA Astrophysics Data System (ADS)

Cipollone, R.

2015-08-01

CO2 reduction and fossil fuel saving represent two of the cornerstones of the environmental commitments of all the countries of the world. The first engagement is of a medium to long term type, and unequivocally calls for a new energetic era. The second delays in time the fossil fuel technologies to favour an energetic transition. In order to sustain the two efforts, new immaterial markets have been established in almost all the countries of the world, whose exchanges (purchases and sales) concern CO2 emissions and equivalent fossil fuels that have not been emitted or burned. This paper goes deep inside two aspects not yet exploited: specific CO2 emissions and equivalent fossil fuel burned, as a function of compressed air produced. Reference is made to the current compressor technology, carefully analysing CAGI's (Compressed Air Gas Institute) data and integrating it with the PNUEROP (European Association of manufacturers of compressors, vacuum pumps, pneumatic tools and allied equipment) contribution on the compressor European market. On the base of energy saving estimates that could be put in place, this article also estimates the financial value of the CO2 emissions and fossil fuels avoided.

Pure Water From a Pure Genius

NASA Technical Reports Server (NTRS)

2002-01-01

Ammonium perchlorate is widely used throughout the aerospace, munitions, and pyrotechnics industries as a primary ingredient in solid rocket and missile propellants, fireworks, and explosive charges. This highly soluble salt has tainted soils and water sources all over the world, and is believed to be an endocrine disrupter, adversely affecting the growth patterns of a fetus or a young child. UMPQUA Research Company (URC), once a small drinking water testing laboratory and a research and development contractor for NASA's manned spaceflight applications, has evolved to become a leader in water purification and analysis. With a total of 11 patents issued for new technologies created by URC under NASA SBIR contracts and a 25-year commitment to water recycling, the company clearly possessed the qualifications necessary to tackle the presence of perchlorate in water. An SBIR contract with NASA's Marshall Space Flight Center that concentrated on the stringent water quality requirements of long-term, manned spaceflight was the source for URC's process and catalyst to facilitate the destruction of perchlorate and nitrate in water. URC licensed the rights of its unique reduction reaction process to Calgon Carbon Corporation for use with the company's perchlorate/nitrate remediation process, otherwise known as ISEP(R).

Conservation voltage regulation (CVR) applied to energy savings by voltage-adjusting equipment through AMI

NASA Astrophysics Data System (ADS)

Lan, B.-R.; Chang, C.-A.; Huang, P.-Y.; Kuo, C.-H.; Ye, Z.-J.; Shen, B.-C.; Chen, B.-K.

2017-11-01

Conservation voltage reduction (CVR) includes peak demand reduction, energy conservation, carbon emission reduction, and electricity bill reduction. This paper analyzes the energy-reduction of Siwei Feeders with applying CVR, which are situated in Penghu region and equipped with smart meters. Furthermore, the applicable voltage reduction range for the feeders will be explored. This study will also investigate how the CVR effect and energy conservation are improved with the voltage control devices integrated. The results of this study can serve as a reference for the Taiwan Power Company to promote and implement voltage reduction and energy conservation techniques. This study is expected to enhance the energy-reduction performance of the Penghu Low Carbon Island Project.

Selective electrochemical reduction of CO2 to CO with a cobalt chlorin complex adsorbed on multi-walled carbon nanotubes in water.

PubMed

Aoi, Shoko; Mase, Kentaro; Ohkubo, Kei; Fukuzumi, Shunichi

2015-06-25

Electrocatalytic reduction of CO2 occurred efficiently using a glassy carbon electrode modified with a cobalt(II) chlorin complex adsorbed on multi-walled carbon nanotubes at an applied potential of -1.1 V vs. NHE to yield CO with a Faradaic efficiency of 89% with hydrogen production accounting for the remaining 11% at pH 4.6.

Method And Reactor For Production Of Aluminum By Carbothermic Reduction Of Alumina

DOEpatents

Aune, Jan Arthur; Johansen, Kai

2004-10-19

A hollow partition wall is employed to feed carbon material to an underflow of a carbothermic reduction furnace used to make aluminum. The partition wall divides a low temperature reaction zone where aluminum oxide is reacted with carbon to form aluminum carbide and a high temperature reaction zone where the aluminum carbide and remaining aluminum oxide are reacted to form aluminum and carbon monoxide.

Nitrogenase Reduction of Carbon-Containing Compounds

PubMed Central

Seefeldt, Lance C.; Yang, Zhi-Yong; Duval, Simon; Dean, Dennis R.

2013-01-01

Nitrogenase is an enzyme found in many bacteria and archaea that catalyzes biological dinitrogen fixation, the reduction of N2 to NH3, accounting for the major input of fixed nitrogen into the biogeochemical N cycle. In addition to reducing N2 and protons, nitrogenase can reduce a number of small, non-physiological substrates. Among these alternative substrates are included a wide array of carbon containing compounds. These compounds have provided unique insights into aspects of the nitrogenase mechanism. Recently, it was shown that carbon monoxide (CO) and carbon dioxide (CO2) can also be reduced by nitrogenase to yield hydrocarbons, opening new insights into the mechanism of small molecule activation and reduction by this complex enzyme as well as providing clues for the design of novel molecular catalysts. PMID:23597875

Nitrogen and Fluorine-Codoped Carbon Nanowire Aerogels as Metal-Free Electrocatalysts for Oxygen Reduction Reaction

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

Fu, Shaofang; Zhu, Chengzhou; Song, Junhua

2017-07-11

The development of active, durable, and low-cost catalysts to replace noble metal-based materials is highly desirable to promote the sluggish oxygen reduction reaction in fuel cells. Herein, nitrogen and fluorine-codoped three-dimensional carbon nanowire aerogels, composed of interconnected carbon nanowires, were synthesized for the first time by a hydrothermal carbonization process. Owing to their porous nanostructures and heteroatom-doping, the as-prepared carbon nanowire aerogels, with optimized composition, present excellent electrocatalytic activity that is comparable to commercial Pt/C. Remarkably, the aerogels also exhibit superior stability and methanol tolerance. This synthesis procedure paves a new way to design novel heteroatomdoped catalysts.

Using Acceptance and Commitment Therapy during Methadone Dose Reduction: Rationale, Treatment Description, and a Case Report

ERIC Educational Resources Information Center

Stotts, Angela L.; Masuda, Akihiko; Wilson, Kelly

2009-01-01

Many clients who undergo methadone maintenance (MM) treatment for heroin and other opiate dependence prefer abstinence from methadone. Attempts at methadone detoxification are often unsuccessful, however, due to distressing physical as well as psychological symptoms. Outcomes from an MM client who voluntarily participated in an Acceptance and…

The Power of Proverbs: Dissonance Reduction through Common Sayings

ERIC Educational Resources Information Center

Stalder, Daniel R.

2010-01-01

After reading a detailed account of a serious mistake in which a similar-age other went against personal values or a prior commitment, undergraduates rated their feelings of dissonance (regret, hypocrisy, and stupidity) had they been in the actor's place. Relative to a control condition, reading relevant proverbs such as "everybody makes mistakes"…

40 CFR 52.2299 - Original identification of plan section.

Code of Federal Regulations, 2011 CFR

2011-07-01

...), Appendix AG, Emission Reduction Commitments for Transportation Control Measures in Post-1982 SIP Areas...; as adopted by the Texas Air Control Board on October 14, 1988. (C) The following portions of the Post... Transportation Control Measures in Post-1982 SIP Areas, as adopted by the Texas Air Control Board on December 18...

40 CFR 52.2299 - Original identification of plan section.

Code of Federal Regulations, 2013 CFR

2013-07-01

...), Appendix AG, Emission Reduction Commitments for Transportation Control Measures in Post-1982 SIP Areas...; as adopted by the Texas Air Control Board on October 14, 1988. (C) The following portions of the Post... Transportation Control Measures in Post-1982 SIP Areas, as adopted by the Texas Air Control Board on December 18...

Do HRD Investment Strategies Pay? Exploring the Relationship between Lifelong Learning and Psychological Contracts.

ERIC Educational Resources Information Center

Martin, Graeme; Pate, Judy; McGoldrick, Jim

1999-01-01

A four-year study of a Scottish manufacturer's employee lifelong learning program discovered a positive relationship between the program and employee perceptions of careers, fairness, and the long-term "psychological contract." Due to reduction in the employer's commitment to job security, employees were beginning to view the program as…

An obesity/cardiometabolic risk reduction disease management program: a population-based approach.

PubMed

Villagra, Victor G

2009-04-01

Obesity is a critical health concern that has captured the attention of public and private healthcare payers who are interested in controlling costs and mitigating the long-term economic consequences of the obesity epidemic. Population-based approaches to obesity management have been proposed that take advantage of a chronic care model (CCM), including patient self-care, the use of community-based resources, and the realization of care continuity through ongoing communications with patients, information technology, and public policy changes. Payer-sponsored disease management programs represent an important conduit to delivering population-based care founded on similar CCM concepts. Disease management is founded on population-based disease identification, evidence-based care protocols, and collaborative practices between clinicians. While substantial clinician training, technology infrastructure commitments, and financial support at the payer level will be needed for the success of disease management programs in obesity and cardiometabolic risk reduction, these barriers can be overcome with the proper commitment. Disease management programs represent an important tool to combat the growing societal risks of overweight and obesity.

Biological uptake of polychlorinated biphenyls by Macoma balthica from sediment amended with activated carbon

USGS Publications Warehouse

McLeod, Pamela B.; van den Heuvel-Greve, Martine J.; Luoma, S.N.; Luthy, R.G.

2007-01-01

This work characterizes the efficacy of activated carbon amendment in reducing polychlorinated biphenyl (PCB) bioavailability to clams (Macoma balthica) from field-contaminated sediment (Hunters Point Naval Shipyard, San Francisco Bay, CA, USA) Test methods were developed for the use of clams to investigate the effects of sediment amendment on biological uptake. Sediment was mixed with activated carbon for one month. Bioaccumulation tests (28 d) were employed to assess the relationships between carbon dose and carbon particle size on observed reductions in clam biological uptake of PCBs. Extraction and cleanup protocols were developed for the clam tissue. Efficacy of activated carbon treatment was found to increase with both increasing carbon dose and decreasing carbon particle size. Average reductions in bioaccumulation of 22, 64, and 84% relative to untreated Hunters Point sediment were observed for carbon amendments of 0.34, 1.7, and 3.4%, respectively. Average bioaccumulation reductions of 41, 73, and 89% were observed for amendments (dose = 1.7% dry wt) with carbon particles of 180 to 250, 75 to 180, and 25 to 75 ??m, respectively, in diameter, indicating kinetic phenomena in these tests. Additionally, a biodynamic model quantifying clam PCB uptake from water and sediment as well as loss through elimination provided a good fit of experimental data. Model predictions suggest that the sediment ingestion route contributed 80 to 95% of the PCB burdens in the clams. ?? 2007 SETAC.

Biogeochemical cycles of carbon, sulfur, and free oxygen in a microbial mat

NASA Technical Reports Server (NTRS)

Canfield, Donald E.; Des Marais, David J.

1993-01-01

Complete budgets for carbon and oxygen have been constructed for cyanobacterial mats dominated by Microcoleus chthonoplastes from the evaporating ponds of a salt works. We infer from the data the various sinks for O2 as well as the sources of carbon for primary production. Although seasonal variability exists, a major percentage of the O2 produced during the day did not diffuse out of the mat but was used within the mat to oxidize both organic carbon and the sulfide produced by sulfate reduction. At night, most of the O2 that diffused into the mat was used to oxidize sulfide, with O2 respiration of minor importance. During the day, the internal mat processes of sulfate reduction and O2 respiration generated as much or more inorganic carbon (DIC) for primary production as diffusion into the mat. Oxygenic photosynthesis was the most important process of carbon fixation. At night, the DIC lost from the mat was mostly from sulfate reduction. Elemental fluxes across the mat/brine interface indicated that carbon with an oxidation state of greater than zero was taken up by the mat during the day and liberated from the mat at night. Overall, carbon with an average oxidation state of near zero accumulated in the mat. Both carbon fixation and carbon oxidation rates varied with temperature by a similar amount.

Nudging Guideline-Concordant Antibiotic Prescribing

PubMed Central

Meeker, Daniella; Knight, Tara K.; Friedberg, Mark W.; Linder, Jeffrey A.; Goldstein, Noah J.; Fox, Craig R.; Rothfeld, Alan; Diaz, Guillermo; Doctor, Jason N.

2015-01-01

IMPORTANCE “Nudges” that influence decision making through subtle cognitive mechanisms have been shown to be highly effective in a wide range of applications, but there have been few experiments to improve clinical practice. OBJECTIVE To investigate the use of a behavioral “nudge” based on the principle of public commitment in encouraging the judicious use of antibiotics for acute respiratory infections (ARIs). DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial in 5 outpatient primary care clinics. A total of 954 adults had ARI visits during the study timeframe: 449 patients were treated by clinicians randomized to the posted commitment letter (335 in the baseline period, 114 in the intervention period); 505 patients were treated by clinicians randomized to standard practice control (384 baseline, 121 intervention). INTERVENTIONS The intervention consisted of displaying poster-sized commitment letters in examination rooms for 12 weeks. These letters, featuring clinician photographs and signatures, stated their commitment to avoid inappropriate antibiotic prescribing for ARIs. MAIN OUTCOMES AND MEASURES Antibiotic prescribing rates for antibiotic-inappropriate ARI diagnoses in baseline and intervention periods, adjusted for patient age, sex, and insurance status. RESULTS Baseline rates were 43.5% and 42.8% for control and poster, respectively. During the intervention period, inappropriate prescribing rates increased to 52.7% for controls but decreased to 33.7% in the posted commitment letter condition. Controlling for baseline prescribing rates, we found that the posted commitment letter resulted in a 19.7 absolute percentage reduction in inappropriate antibiotic prescribing rate relative to control (P = .02). There was no evidence of diagnostic coding shift, and rates of appropriate antibiotic prescriptions did not diminish over time. CONCLUSIONS AND RELEVANCE Displaying poster-sized commitment letters in examination rooms decreased inappropriate antibiotic prescribing for ARIs. The effect of this simple, low-cost intervention is comparable in magnitude to costlier, more intensive quality-improvement efforts. TRIAL REGISTRATION clinicaltrials.gov identifier: NCT01767064 PMID:24474434

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

NONE

The Illinois Solid Waste Management Act, enacted in September 1986, established the State`s commitment to adress solid waste handling, based on a solid waste management hierarchy as folloew: (1) volume reduction at the source; (2) recycling and reuse; (3) combustion with energy recovery; (4) combustion for volume reduction; and (5) disposal in landfill facilities. Under this Act, the Illinois Environmental Protection Agency (IEPA) is required to publish an annual report `regarding the projected disposal capacity available for solid waste in sanitary landfills`. The information presented in this report reflects the reporting period January 1, 1994 - Decenber 31, 1994.

The Healthy Wight Commitment Foundation pledge: calories purchased by U.S. households with children, 2000-2012.

PubMed

Ng, Shu Wen; Popkin, Barry M

2014-10-01

An independent evaluation of the Healthy Weight Commitment Foundation (HWCF) marketplace pledge found that the participating companies met and exceeded their interim 2012 sales reduction pledge. This follow-up study conducted in 2013 used purchase data from 2000 to 2012 among U.S. households with children and compared trends in calorie purchases of HWCF, non-HWCF name brands, and private label (PL) products in the pre-pledge period (2000-2007) and the post-pledge period (2008-2012); controlled for potential effects of concurrent changes in demographic and economic factors, including the Great Recession and food prices; and assessed whether the HWCF marketplace pledge was associated with reductions in consumer packaged goods (CPG) calorie purchases by households with children. There has been a significant per capita decline in average daily CPG caloric purchases between 2000 and 2012 among households with children from all brand categories. Based on pre-pledge trends, declines in CPG caloric purchases were already occurring. However, post-pledge reductions in calories purchased from HWCF brands were less than expected, and reductions in calories purchased from non-HWCF name brands and PLs were greater than expected after economic, sociodemographic, and secular factors were accounted for. If the 16 HWCF companies had been able to maintain their pre-pledge trajectory, there should have been an additional 42 kcal/capita/day reduction in calories purchased from HWCF products in 2012 among households with children. A lack of change in total CPG calories purchased between 2011 and 2012 calls into question the sustainability of the decline and a need for continued monitoring. Copyright © 2014 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Solvent decompositions and physical properties of decomposition compounds in Li-ion battery electrolytes studied by DFT calculations and molecular dynamics simulations.

PubMed

Tasaki, Ken

2005-02-24

The density functional theory (DFT) calculations have been performed for the reduction decompositions of solvents widely used in Li-ion secondary battery electrolytes, ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonates (DMC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC), including a typical electrolyte additive, vinylene carbonate (VC), at the level of B3LYP/6-311+G(2d,p), both in the gas phase and solution using the polarizable conductor calculation model. In the gas phase, the first electron reduction for the cyclic carbonates and for the linear carbonates is found to be exothermic and endothermic, respectively, while the second electron reduction is endothermic for all the compounds examined. On the contrary, in solution both first and second electron reductions are exothermic for all the compounds. Among the solvents and the additive examined, the likelihood of undergoing the first electron reduction in solution was found in the order of EC > PC > VC > DMC > EMC > DEC with EC being the most likely reduced. VC, on the other hand, is most likely to undergo the second electron reduction among the compounds, in the order of VC > EC > PC. Based on the results, the experimentally demonstrated effectiveness of VC as an excellent electrolyte additive was discussed. The bulk thermodynamic properties of two dilithium alkylene glycol dicarbonates, dilithium ethylene glycol dicarbonate (Li-EDC) and dilithium 1,2-propylene glycol dicarbonate (Li-PDC), as the major component of solid-electrolyte interface (SEI) films were also examined through molecular dynamics (MD) simulations in order to understand the stability of the SEI film. It was found that film produced from a decomposition of EC, modeled by Li-EDC, has a higher density, more cohesive energy, and less solubility to the solvent than the film produced from decomposition of PC, Li-PDC. Further, MD simulations of the interface between the decomposition compound and graphite suggested that Li-EDC has more favorable interactions with the graphite surface than Li-PDC. The difference in the SEI film stability and the behavior of Li-ion battery cycling among the solvents were discussed in terms of the molecular structures.

Energy technologies evaluated against climate targets using a cost and carbon trade-off curve.

PubMed

Trancik, Jessika E; Cross-Call, Daniel

2013-06-18

Over the next few decades, severe cuts in emissions from energy will be required to meet global climate-change mitigation goals. These emission reductions imply a major shift toward low-carbon energy technologies, and the economic cost and technical feasibility of mitigation are therefore highly dependent upon the future performance of energy technologies. However, existing models do not readily translate into quantitative targets against which we can judge the dynamic performance of technologies. Here, we present a simple, new model for evaluating energy-supply technologies and their improvement trajectories against climate-change mitigation goals. We define a target for technology performance in terms of the carbon intensity of energy, consistent with emission reduction goals, and show how the target depends upon energy demand levels. Because the cost of energy determines the level of adoption, we then compare supply technologies to one another and to this target based on their position on a cost and carbon trade-off curve and how the position changes over time. Applying the model to U.S. electricity, we show that the target for carbon intensity will approach zero by midcentury for commonly cited emission reduction goals, even under a high demand-side efficiency scenario. For Chinese electricity, the carbon intensity target is relaxed and less certain because of lesser emission reductions and greater variability in energy demand projections. Examining a century-long database on changes in the cost-carbon space, we find that the magnitude of changes in cost and carbon intensity that are required to meet future performance targets is not unprecedented, providing some evidence that these targets are within engineering reach. The cost and carbon trade-off curve can be used to evaluate the dynamic performance of existing and new technologies against climate-change mitigation goals.

Nitrogen reduction pathways in estuarine sediments: Influences of organic carbon and sulfide

NASA Astrophysics Data System (ADS)

Plummer, Patrick; Tobias, Craig; Cady, David

2015-10-01

Potential rates of sediment denitrification, anaerobic ammonium oxidation (anammox), and dissimilatory nitrate reduction to ammonium (DNRA) were mapped across the entire Niantic River Estuary, CT, USA, at 100-200 m scale resolution consisting of 60 stations. On the estuary scale, denitrification accounted for ~ 90% of the nitrogen reduction, followed by DNRA and anammox. However, the relative importance of these reactions to each other was not evenly distributed through the estuary. A Nitrogen Retention Index (NIRI) was calculated from the rate data (DNRA/(denitrification + anammox)) as a metric to assess the relative amounts of reactive nitrogen being recycled versus retained in the sediments following reduction. The distribution of rates and accompanying sediment geochemical analytes suggested variable controls on specific reactions, and on the NIRI, depending on position in the estuary and that these controls were linked to organic carbon abundance, organic carbon source, and pore water sulfide concentration. The relationship between NIRI and organic carbon abundance was dependent on organic carbon source. Sulfide proved the single best predictor of NIRI, accounting for 44% of its observed variance throughout the whole estuary. We suggest that as a single metric, sulfide may have utility as a proxy for gauging the distribution of denitrification, anammox, and DNRA.

Comparison of heterogeneous photolytic reduction of Hg(II) in the coal fly ashes and synthetic aerosols

NASA Astrophysics Data System (ADS)

Tong, Yindong; Eichhorst, Terry; Olson, Michael R.; Rutter, Andrew P.; Shafer, Martin M.; Wang, Xuejun; Schauer, James J.

2014-03-01

In this study, we examined the heterogeneous reduction of Hg(II) on the coal fly ash samples and synthetic aerosols under different light conditions in a controlled laboratory reactor. Three types of coal fly ashes were studied: a high carbon fly ash from a stoker boiler, a low carbon/low sulfate fly ash from a pulverized coal combustor burning low sulfur coal, and a high sulfate fly ash from a pulverized coal combustor burning high sulfur coal. The rate of Hg(II) reduction on the three diverse fly ash samples was found to be relatively fast with an average half-life of 1.6 h under clear sky atmospheric conditions (under the irradiance of 1000 W/m2). The reduction rate in the low sulfate/low carbon fly ash was approximately 1.5 times faster than with the other coal fly ash samples. Synthetic aerosols made of carbon black and levoglucosan produced Hg(II) reduction rates similar to coal fly ashes. However, aerosols composed of adipic acid resulted in reduction rates that were 3-5 times faster. The sensitivity of adipic acid reduction to light source wavelength was found to be greater than for the coal fly ash and other synthetic aerosols. Aerosols made from the water extracts of coal fly ash samples produced reduction rates equal to or slightly higher than with the native fly ash suggesting that the soluble components of fly ash play a significant role in the reduction mechanism. The measured reduction rates are likely important in the chemical processing of mercury in power plant plumes and potentially in the atmosphere and should be considered for incorporation in atmospheric transport models that are used to understand the fate of atmospheric mercury.

Carbon-dependent chromate toxicity mechanism in an environmental Arthrobacter isolate.

PubMed

Field, Erin K; Blaskovich, John P; Peyton, Brent M; Gerlach, Robin

2018-05-12

Arthrobacter spp. are widespread in soil systems and well-known for their Cr(VI) reduction capabilities making them attractive candidates for in situ bioremediation efforts. Cellulose drives carbon flow in soil systems; yet, most laboratory studies evaluate Arthrobacter-Cr(VI) interactions solely with nutrient-rich media or glucose. This study aims to determine how various cellulose degradation products and biostimulation substrates influence Cr(VI) toxicity, reduction, and microbial growth of an environmental Arthrobacter sp. isolate. Laboratory culture-based studies suggest there is a carbon-dependent Cr(VI) toxicity mechanism that affects subsequent Cr(VI) reduction by strain LLW01. Strain LLW01 could only grow in the presence of, and reduce, 50 μM Cr(VI) when glucose or lactate were provided. Compared to lactate, Cr(VI) was at least 30-fold and 10-fold more toxic when ethanol or butyrate was the sole carbon source, respectively. The addition of sulfate mitigated toxicity somewhat, but had no effect on the extent of Cr(VI) reduction. Cell viability studies indicated that a small fraction of cells were viable after 8 days suggesting cell growth and subsequent Cr(VI) reduction may resume. These results suggest when designing bioremediation strategies with Arthrobacter spp. such as strain LLW01, carbon sources such as glucose and lactate should be considered over ethanol and butyrate. Copyright © 2018 Elsevier B.V. All rights reserved.

A sociodrama: an innovative program engaging college students to learn and self-reflect about alcohol use.

PubMed

Haleem, Diane M; Winters, Justin

2011-08-01

A sociodrama addressing college drinking.   This article reports on the development, production, and evaluation of an innovative sociodrama addressing college drinking mental health professionals caring for students who drink at levels that cause negative consequences can use techniques addressed in the sociodrama to help students self-reflect on their alcohol use. The goal is to help students make healthy choices to decrease the negative consequences as a result of drinking. A script for the sociodrama was developed and five students acted out the sociodrama. A facilitator engaged the audience of college students, at scripted pauses, during the production to reflect on the scenes presented. The purpose of the sociodrama is to foster a discussion, to aid in student understanding concerning college drinking, to have students consider and commit to use harm reduction techniques, to access resources, and to correct misperceptions about drinking. The sociodrama format can help address communication challenges, problem solving, and self-awareness. Pre- and post-surveys were administered to test commitment to use harm reduction techniques, assess the perception of a student's own drinking pattern to the perception of their fellow student colleague drinking, assess the student use of resources, and assess the effectiveness of the sociodrama as a means of learning. This research was Institutional Review Board approved. Over 41% of students reported not consuming alcohol the last time they partied or socialized yet reported only 3.8% of their students colleagues did not consume alcohol. Most students (94%) reported that drinking five or more drinks would place them at risk as opposed to estimating that the same amount would put fewer students at risk (75%). Students significantly increased their commitment to use harm reduction techniques. A sociodrama is an effective method of involving students in discussions about college drinking and engaging them in conversation and self-reflection. © 2011 Wiley Periodicals, Inc.

Pricing, Carbon Emission Reduction, Low-Carbon Promotion and Returning Decision in a Closed-Loop Supply Chain under Vertical and Horizontal Cooperation

PubMed Central

Li, Hui; Wang, Chuanxu; Shang, Meng; Ou, Wei

2017-01-01

In this paper, we examine the influences of vertical and horizontal cooperation models on the optimal decisions and performance of a low-carbon closed-loop supply chain (CLSC) with a manufacturer and two retailers, and study optimal operation in the competitive pricing, competitive the low-carbon promotion, the carbon emission reduction, the used-products collection and the profits. We consider the completely decentralized model, M-R vertical cooperation model, R-R horizontal cooperation model, M-R-R vertical and horizontal cooperation model and completely centralized model, and also identify the optimal decision results and profits. It can be observed from a systematic comparison and numerical analysis that the completely centralized model is best in all optimal decision results among all models. In semi-cooperation, the M-R vertical cooperation model is positive, the R-R horizontal cooperation model is passive, and the positivity of the M-R-R vertical and horizontal cooperation model decreases with competitive intensity increasing in the used-products returning, carbon emissions reduction level, low-carbon promotion effort and the profits of the manufacturer and the entire supply chain. PMID:29104268

Pricing, Carbon Emission Reduction, Low-Carbon Promotion and Returning Decision in a Closed-Loop Supply Chain under Vertical and Horizontal Cooperation.

PubMed

Li, Hui; Wang, Chuanxu; Shang, Meng; Ou, Wei

2017-11-01

In this paper, we examine the influences of vertical and horizontal cooperation models on the optimal decisions and performance of a low-carbon closed-loop supply chain (CLSC) with a manufacturer and two retailers, and study optimal operation in the competitive pricing, competitive the low-carbon promotion, the carbon emission reduction, the used-products collection and the profits. We consider the completely decentralized model, M-R vertical cooperation model, R-R horizontal cooperation model, M-R-R vertical and horizontal cooperation model and completely centralized model, and also identify the optimal decision results and profits. It can be observed from a systematic comparison and numerical analysis that the completely centralized model is best in all optimal decision results among all models. In semi-cooperation, the M-R vertical cooperation model is positive, the R-R horizontal cooperation model is passive, and the positivity of the M-R-R vertical and horizontal cooperation model decreases with competitive intensity increasing in the used-products returning, carbon emissions reduction level, low-carbon promotion effort and the profits of the manufacturer and the entire supply chain.

Biogeochemical cycles of carbon, sulfur, and free oxygen in a microbial mat

NASA Astrophysics Data System (ADS)

Canfield, Donald E.; Des Marais, David J.

1993-08-01

Complete budgets for carbon and oxygen have been constructed for cyanobacterial mats dominated by Microcoleus chthonoplastes from the evaporating ponds of a salt works located in Guerrero Negro, Baja California Sur, Mexico. Included in the budget are measured rates of O 2 production, sulfate reduction, and elemental exchange across the mat/brine interface, day and night, at various temperatures and times of the year. We infer from this data the various sinks for O 2, as well as the sources of carbon for primary production. To summarize, although seasonal variability exists, a major percentage of the O 2 produced during the day did not diffuse out of the mat but was used within the mat to oxidize both organic carbon and the sulfide produced by sulfate reduction. At night, most of the O 2 that diffused into the mat was used to oxidize sulfide, with O 2 respiration of minor importance. During the day, the internal mat processes of sulfate reduction and O 2 respiration generated as much or more inorganic carbon (DIC) for primary production as diffusion into the mat. Also, oxygenic photosynthesis was the most important process of carbon fixation, although anoxygenic photosynthesis may have been important at low light levels during some times of the year. At night, the DIC lost from the mat was mostly from sulfate reduction. Elemental fluxes across the mat/brine interface indicated that carbon with an oxidation state of greater than zero was taken up by the mat during the day and liberated from the mat at night. Overall, carbon with an average oxidation state of near zero accumulated in the mat. Both carbon fixation and carbon oxidation rates varied with temperature by a similar amount. These mats are thus closely coupled systems where rapid rates of photosynthesis both require and fuel rapid rates of heterotrophic carbon oxidation.

The market effectiveness of electricity reform: A case of carbon emissions trading market of Shenzhen city

NASA Astrophysics Data System (ADS)

Wang, Yongli; Wang, Gang; Zuo, Yi; Fan, Lisha; Xiao, Yao

2017-03-01

In the 13th Five-Year Plan, the Chinese government proposed to achieve the national carbon emission trading market established by 2017. The establishment of carbon emission trading market is the most important one in power reform, which helps to promote the power reform and achieve the goal of energy saving and emission reduction. As the bond of connecting environment energy issues and the economic development, carbon emissions trading market has become a hot research topic in the related fields, by market means, it incentive the lower cost subject emissions to undertake more reductions and therefore to benefit, the body of the high cost finished the task by buying quota reduction, to achieve the effect of having the least social total cost. Shenzhen has become the first city in China to start carbon trading pilot formally on June 16, 2013, online trading on June 18. The paper analyzes the market effectiveness of electricity reform in China, which takes carbon emissions trading market of Shenzhen city for example, and gives some suggestions for future development.

Functionalization of multi-walled carbon nanotubes with iron phthalocyanine via a liquid chemical reaction for oxygen reduction in alkaline media

NASA Astrophysics Data System (ADS)

Yan, Xiaomei; Xu, Xiao; Liu, Qin; Guo, Jia; Kang, Longtian; Yao, Jiannian

2018-06-01

Iron single-atom catalyst in form of iron-nitrogen-carbon structure possesses the excellent catalytic activity in various chemical reactions. However, exploring a sustainable and stable single-atom metal catalyst still faces a great challenge due to low yield and complicated synthesis. Here, we report a functional multi-wall carbon nanotubes modified with iron phthalocyanine molecules via a liquid chemical reaction and realize the performance of similar single-atom catalysis for oxygen reduction reaction. A serial of characterizations strongly imply the structure change of iron phthalocyanine molecule and its close recombination with multi-wall carbon nanotubes, which are in favor of ORR catalysis. Compared to commercial platinum-carbon catalyst, composites exhibit superior activity for oxygen reduction reaction with higher half-wave potential (0.86 V), lower Tafel slope (38 mV dec-1), higher limiting current density and excellent electrochemical stability. The corresponding Zinc-air battery also presents higher maximum power density and discharge stability. Therefore, these findings provide a facile route to synthesize a highly efficient non-precious metal carbon-based catalyst.

Biomass enables the transition to a carbon-negative power system across western North America

NASA Astrophysics Data System (ADS)

Sanchez, Daniel L.; Nelson, James H.; Johnston, Josiah; Mileva, Ana; Kammen, Daniel M.

2015-03-01

Sustainable biomass can play a transformative role in the transition to a decarbonized economy, with potential applications in electricity, heat, chemicals and transportation fuels. Deploying bioenergy with carbon capture and sequestration (BECCS) results in a net reduction in atmospheric carbon. BECCS may be one of the few cost-effective carbon-negative opportunities available should anthropogenic climate change be worse than anticipated or emissions reductions in other sectors prove particularly difficult. Previous work, primarily using integrated assessment models, has identified the critical role of BECCS in long-term (pre- or post-2100 time frames) climate change mitigation, but has not investigated the role of BECCS in power systems in detail, or in aggressive time frames, even though commercial-scale facilities are starting to be deployed in the transportation sector. Here, we explore the economic and deployment implications for BECCS in the electricity system of western North America under aggressive (pre-2050) time frames and carbon emissions limitations, with rich technology representation and physical constraints. We show that BECCS, combined with aggressive renewable deployment and fossil-fuel emission reductions, can enable a carbon-negative power system in western North America by 2050 with up to 145% emissions reduction from 1990 levels. In most scenarios, the offsets produced by BECCS are found to be more valuable to the power system than the electricity it provides. Advanced biomass power generation employs similar system design to advanced coal technology, enabling a transition strategy to low-carbon energy.

Magnetic cobaltic nanoparticle-anchored carbon nanocomposite derived from cobalt-dipicolinic acid coordination polymer: An enhanced catalyst for environmental oxidative and reductive reactions.

PubMed

Wu, Chang-Hsun; Lin, Jyun-Ting; Lin, Kun-Yi Andrew

2018-05-01

Direct carbonization of cobalt complexes represents as a convenient approach to prepare magnetic carbon/cobalt nanocomposites (MCCNs) as heterogeneous environmental catalysts. However, most of MCCNs derived from consist of sheet-like carbon matrices with very sparse cobaltic nanoparticles (NPs), making them exhibit relatively low catalytic activities, porosity and magnetism. In this study, dipicolinic acid (DPA) is selected to prepare a 3-dimensional cobalt coordination polymer (CoDPA). MCCN derived from CoDPA can consist of a porous carbon matrix embedded with highly-dense Co 0 and Co 3 O 4 NPs. This magnetic Co 0 /Co 3 O 4 NP-anchored carbon composite (MCNC) appears as a promising heterogeneous catalyst for oxidative and reductive environmental catalytic reactions. As peroxymonosulfate (PMS) activation is selected as a model catalytic oxidative reaction, MCNC exhibits a much higher catalytic activity than Co 3 O 4 , a benchmark catalyst for PMS activation. The reductive catalytic activity of MCNC is demonstrated through 4-nitrophenol (4-NP) reduction in the presence of NaBH 4 . MCNC could rapidly react with NaBH 4 to generate H 2 for hydrogenation of 4-NP to 4-aminophenol (4-AP). In comparison with other precious metallic catalysts, MCNC also shows a relatively high catalytic activity. These results indicate that MCNC is a conveniently prepared and highly effective and stable carbon-supported cobaltic heterogeneous catalyst for versatile environmental catalytic applications. Copyright © 2018 Elsevier Inc. All rights reserved.

A heat transfer model for incorporating carbon foam fabrics in firefighter's garment

NASA Astrophysics Data System (ADS)

Elgafy, Ahmed; Mishra, Sarthak

2014-04-01

In the present work, a numerical study was performed to predict and investigate the performance of a thermal protection system for firefighter's garment consisting of carbon foam fabric in both the outer shell and the thermal liner elements. Several types of carbon foam with different thermal conductivity, porosity, and density were introduced to conduct a parametric study. Additionally, the thickness of the introduced carbon foam fabrics was varied to acquire optimum design. Simulation was conducted for a square planar 2D geometry of the clothing comprising of different fabric layers and a double precision pressure-based implicit solver, under transient state condition was used. The new anticipated thermal protection system was tested under harsh thermal environmental conditions that firefighters are exposed to. The parametric study showed that employing carbon foam fabric with one set of designed parameters, weight reduction of 33 % in the outer shell, 56 % in the thermal liner and a temperature reduction of 2 % at the inner edge of the garment was achieved when compared to the traditional firefighter garment model used by Song et al. (Int J Occup Saf Ergon 14:89-106, 2008). Also, carbon foam fabric with another set of designed parameters resulted in a weight reduction of 25 % in the outer shell, 28 % in the thermal liner and a temperature reduction of 6 % at the inner edge of the garment. As a result, carbon foam fabrics make the firefighter's garment more protective, durable, and lighter in weight.

Development and characterization of hybrid thermoplastic composites

NASA Astrophysics Data System (ADS)

Karkhanis, Priyanka Chandrashekhar

This work is aimed at studying the possibility of using interply hybrid woven thermoplastic semi-pregs in secondary structures in aircrafts at TenCate Advanced Composites, Netherlands and Purdue University. Three different interply hybrids were designed from combination of Cetex(c) carbon-PPS semi-preg, Owen corning's woven glass with PPS sheets and discontinuous chopped Cetex(c) carbon-PPS semi-preg to get desired flexural, out of plane and bearing properties. The design calculations are done based on classical laminate theory and the selection of materials to be used with carbon-PPS was done based on cost and availability. The Hybrid laminate performances are analyzed and compared to the conventional Cetex (c) Carbon-PPS semi-preg laminates. Observations are reported on three point bend test (European standard 2562), four point bend test(ASTM D6415-99) and bearing test (Airbus standards AITM 1-0009) for the laminates and it was found that hybrid laminates show a reduction of 5-10% in bending stiffness, 20-40% reduction in out-of-plane strength and 2-5%reduction in bearing with a cost reduction of 20-30%. The research identifies and documents the different factors responsible for failures and reduction in strength in the Hybrids.

Activated Carbon Textile via Chemistry of Metal Extraction for Supercapacitors.

PubMed

Lam, Do Van; Jo, Kyungmin; Kim, Chang-Hyun; Kim, Jae-Hyun; Lee, Hak-Joo; Lee, Seung-Mo

2016-12-27

Carbothermic reduction in the chemistry of metal extraction (MO(s) + C(s) → M(s) + CO(g)) using carbon as a sacrificial agent has been used to smelt metals from diverse oxide ores since ancient times. Here, we paid attention to another aspect of the carbothermic reduction to prepare an activated carbon textile for high-rate-performance supercapacitors. On the basis of thermodynamic reducibility of metal oxides reported by Ellingham, we employed not carbon, but metal oxide as a sacrificial agent in order to prepare an activated carbon textile. We conformally coated ZnO on a bare cotton textile using atomic layer deposition, followed by pyrolysis at high temperature (C(s) + ZnO(s) → C'(s) + Zn(g) + CO(g)). We figured out that it leads to concurrent carbonization and activation in a chemical as well as mechanical way. Particularly, the combined effects of mechanical buckling and fracture that occurred between ZnO and cotton turned out to play an important role in carbonizing and activating the cotton textile, thereby significantly increasing surface area (nearly 10 times) compared with the cotton textile prepared without ZnO. The carbon textiles prepared by carbothermic reduction showed impressive combination properties of high power and energy densities (over 20-fold increase) together with high cyclic stability.

Deposition of platinum nanoparticles on carbon nanotubes by supercritical fluid method.

PubMed

Yen, Clive H; Cui, Xiaoli; Pan, Horng-Bin; Wang, Shaofen; Lin, Yuehe; Wai, Chien M

2005-11-01

Carbon nanotube-supported platinum nanoparticles with a 5-15 nm diameter size range can be synthesized by hydrogen reduction of platinum(ll) acetylacetonate in methanol modified supercritical carbon dioxide. X-ray photoelectron spectroscopy and X-ray diffraction spectra indicate that the carbon nanotubes contain zero-valent platinum metal and high-resolution transmission electron microscopy images show that the visible lattice fringes of platinum nanoparticles are crystallites. Carbon nanotubes synthesized with 25% by weight of platinum nanoparticles exhibit a higher activity for hydrogenation of benzene compared with a commercial carbon black platinum catalyst. The carbon nanotube-supported platinum nanocatalyst can be reused at least six times for the hydrogenation reaction without losing activity. The carbon nanotube-supported platinum nanoparticles are also highly active for electrochemical oxidation of methanol and for reduction of oxygen suggesting their potential use as a new electrocatalyst for proton exchange membrane fuel cell applications.

A Unique 3D Nitrogen-Doped Carbon Composite as High-Performance Oxygen Reduction Catalyst

PubMed Central

Karunagaran, Ramesh; Tung, Tran Thanh; Tran, Diana; Coghlan, Campbell; Doonan, Christian

2017-01-01

The synthesis and properties of an oxygen reduction catalyst based on a unique 3-dimensional (3D) nitrogen doped (N-doped) carbon composite are described. The composite material is synthesised via a two-step hydrothermal and pyrolysis method using bio-source low-cost materials of galactose and melamine. Firstly, the use of iron salts and galactose to hydrothermally produceiron oxide (Fe2O3) magnetic nanoparticle clusters embedded carbon spheres. Secondly, magnetic nanoparticles diffused out of the carbon sphere when pyrolysed in the presence of melamine as nitrogen precursor. Interestingly, many of these nanoparticles, as catalyst-grown carbon nanotubes (CNTs), resulted in the formation of N-doped CNTs and N-doped carbon spheres under the decomposition of carbon and a nitrogen environment. The composite material consists of integrated N-doped carbon microspheres and CNTs show high ORR activity through a predominantly four-electron pathway. PMID:28792432

Sources and turnover of organic carbon and methane in fjord and shelf sediments off northern Norway

NASA Astrophysics Data System (ADS)

Sauer, Simone; Hong, Wei-Li; Knies, Jochen; Lepland, Aivo; Forwick, Matthias; Klug, Martin; Eichinger, Florian; Baranwal, Soma; Crémière, Antoine; Chand, Shyam; Schubert, Carsten J.

2016-10-01

To better understand the present and past carbon cycling and transformation processes in methane-influenced fjord and shelf areas of northern Norway, we compared two sediment cores from the Hola trough and from Ullsfjorden. We investigated (1) the organic matter composition and sedimentological characteristics to study the sources of organic carbon (Corg) and the factors influencing Corg burial, (2) pore water geochemistry to determine the contribution of organoclastic sulfate reduction and methanogenesis to total organic carbon turnover, and (3) the carbon isotopic signature of hydrocarbons to identify the carbon transformation processes and gas sources. High sedimentation and Corg accumulation rates in Ullsfjorden support the notion that fjords are important Corg sinks. The depth of the sulfate-methane-transition (SMT) in the fjord is controlled by the supply of predominantly marine organic matter to the sediment. Organoclastic sulfate reduction accounts for 60% of the total depth-integrated sulfate reduction in the fjord. In spite of the presence of ethane, propane, and butane, we suggest a purely microbial origin of light hydrocarbons in the sediments based on their low δ13C values. In the Hola trough, sedimentation and Corg accumulation rates changed during the deglacial-to-post-glacial transition from approximately 80 cm ka-1 to erosion at present. Thus, Corg burial in this part of the shelf is presently absent. Low organic matter content in the sediment and low rates of organoclastic sulfate reduction (only 3% of total depth-integrated sulfate reduction) entail that the shallow depth of the SMT is controlled mostly by ascending thermogenic methane from deeper sources.

Water and energy link in the cities of the future - achieving net zero carbon and pollution emissions footprint.

PubMed

Novotny, V

2011-01-01

This article discusses the link between water conservation, reclamation, reuse and energy use as related to the goal of achieving the net zero carbon emission footprint in future sustainable cities. It defines sustainable ecocities and outlines quantitatively steps towards the reduction of energy use due to water and used water flows, management and limits in linear and closed loop water/stormwater/wastewater management systems. The three phase water energy nexus diagram may have a minimum inflection point beyond which reduction of water demand may not result in a reduction of energy and carbon emissions. Hence, water conservation is the best alternative solution to water shortages and minimizing the carbon footprint. A marginal water/energy chart is developed and proposed to assist planners in developing future ecocities and retrofitting older communities to achieve sustainability.

Role of water and carbonates in photocatalytic transformation of CO{sub 2} to CH{sub 4} on titania.

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

Dimitrijevic, N. M.; Vijayan, B. K.; Poluektov, O. G.

Using the electron paramagnetic resonance technique, we have elucidated the multiple roles of water and carbonates in the overall photocatalytic reduction of carbon dioxide to methane over titania nanoparticles. The formation of H atoms (reduction product) and {center_dot}OH radicals (oxidation product) from water, and CO{sub 3}{sup -} radical anions (oxidation product) from carbonates, was detected in CO{sub 2}-saturated titania aqueous dispersion under UV illumination. Additionally, methoxyl, {center_dot}OCH{sub 3}, and methyl, {center_dot}CH{sub 3}, radicals were identified as reaction intermediates. The two-electron, one-proton reaction proposed as an initial step in the reduction of CO{sub 2} on the surface of TiO{sub 2} ismore » supported by the results of first-principles calculations.« less

Role of Water and Carbonates in Photocatalytic Transformation of CO2 to CH4 on Titania

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

Dimitrijevic, Nada; Vijayan, Baiju K.; Poluektov, Oleg G.

Using the electron paramagnetic resonance technique, we have elucidated the multiple roles of water and carbonates in the overall photocatalytic reduction of carbon dioxide to methane over titania nanoparticles. The formation of H atoms (reduction product) and {sm_bullet}OH radicals (oxidation product) from water, and CO{sub 3}{sup -} radical anions (oxidation product) from carbonates, was detected in CO{sub 2}-saturated titania aqueous dispersion under UV illumination. Additionally, methoxyl, {sm_bullet}OCH{sub 3}, and methyl, {sm_bullet}CH{sub 3}, radicals were identified as reaction intermediates. The two-electron, one-proton reaction proposed as an initial step in the reduction of CO{sub 2}, on the surface of TiO{sub 2}, ismore » supported by the results of first-principles calculations.« less

Metal-nitrogen doping of mesoporous carbon/graphene nanosheets by self-templating for oxygen reduction electrocatalysts.

PubMed

Li, Shuang; Wu, Dongqing; Liang, Haiwei; Wang, Jinzuan; Zhuang, Xiaodong; Mai, Yiyong; Su, Yuezeng; Feng, Xinliang

2014-11-01

We demonstrate a general and efficient self-templating strategy towards transition metal-nitrogen containing mesoporous carbon/graphene nanosheets with a unique two-dimensional (2D) morphology and tunable mesoscale porosity. Owing to the well-defined 2D morphology, nanometer-scale thickness, high specific surface area, and the simultaneous doping of the metal-nitrogen compounds, the as-prepared catalysts exhibits excellent electrocatalytic activity and stability towards the oxygen reduction reaction (ORR) in both alkaline and acidic media. More importantly, such a self-templating approach towards two-dimensional porous carbon hybrids with diverse metal-nitrogen doping opens up new avenues to mesoporous heteroatom-doped carbon materials as electrochemical catalysts for oxygen reduction and hydrogen evolution, with promising applications in fuel cell and battery technologies. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

40 CFR 60.2115 - What if I do not use a wet scrubber to comply with the emission limitations?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., activated carbon injection, selective noncatalytic reduction, or an electrostatic precipitator to comply..., activated carbon injection, selective noncatalytic reduction, fabric filter, or an electrostatic precipitator or limit emissions in some other manner, including material balances, to comply with the emission...

40 CFR 60.2115 - What if I do not use a wet scrubber to comply with the emission limitations?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., activated carbon injection, selective noncatalytic reduction, or an electrostatic precipitator to comply..., activated carbon injection, selective noncatalytic reduction, fabric filter, or an electrostatic precipitator or limit emissions in some other manner, including material balances, to comply with the emission...

40 CFR 60.2680 - What if I do not use a wet scrubber to comply with the emission limitations?

Code of Federal Regulations, 2012 CFR

2012-07-01

..., activated carbon injection, selective noncatalytic reduction, or an electrostatic precipitator to comply..., activated carbon injection, selective noncatalytic reduction, fabric filter, or an electrostatic precipitator or limit emissions in some other manner, including mass balances, to comply with the emission...

Removing lead in drinking water with activated carbon

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

Taylor, R.M.; Kuennen, R.W.

A point-of-use (POU) granular activated carbon (GAC) fixed bed adsorber (FBA) was evaluated for reduction of soluble and insoluble lead from drinking water. Some of the factors which affect lead removal by GAC were evaluated, such as carbon type, solution pH, and a limited amount of work on competitive interactions. The design criteria for lead reduction by a POU device are also addressed. Minicolumns were used to evaluate the capacity of carbon for lead under a variety of conditions. The importance of surface chemistry of the carbon and the relationship with the pH of the water for lead reduction wasmore » demonstrated. Results indicate that a properly designed POU-GAC-FBA can reduce lead in drinking water to below the EPA action level of 15 ppb while being tested under a variety of conditions as specified under the National Sanitation Foundation (NSF) International Standard 53 test protocol. 37 refs., 9 figs., 1 tab.« less

Microbial Electrosynthesis: Feeding Microbes Electricity To Convert Carbon Dioxide and Water to Multicarbon Extracellular Organic Compounds

PubMed Central

Nevin, Kelly P.; Woodard, Trevor L.; Franks, Ashley E.; Summers, Zarath M.; Lovley, Derek R.

2010-01-01

The possibility of providing the acetogenic microorganism Sporomusa ovata with electrons delivered directly to the cells with a graphite electrode for the reduction of carbon dioxide to organic compounds was investigated. Biofilms of S. ovata growing on graphite cathode surfaces consumed electrons with the reduction of carbon dioxide to acetate and small amounts of 2-oxobutyrate. Electrons appearing in these products accounted for over 85% of the electrons consumed. These results demonstrate that microbial production of multicarbon organic compounds from carbon dioxide and water with electricity as the energy source is feasible. PMID:20714445

Overview of the U.S. Environmental Protection Agency's Hazardous Air Pollutant Early Reduction Program.

PubMed

Laznow, J; Daniel, J

1992-01-01

Under provision of the Clean Air Act Amendments of 1990 Title III, the EPA has proposed a regulation (Early Reduction Program) to allow a six-year compliance extension from Maximum Achievable Control Technology (MACT) standards for sources that voluntarily reduce emissions of Hazardous Air Pollutants (HAPs) by 90 percent or more (95 percent or more for particulates) from a base year of 1987 or later. The emission reduction must be made before the applicable MACT standard is proposed for the source category or be subject to an enforceable commitment to achieve the reduction by January 1, 1994 for sources subject to MACT standards prior to 1994. The primary purpose of this program is to encourage reduction of HAPs emissions sooner than otherwise required. Industry would be allowed additional time in evaluating emission reduction options and developing more cost-effective compliance strategies, although, under strict guidelines to ensure actual, significant and verifiable emission reductions occur.

Sulfate reduction in sulfuric material after re-flooding: Effectiveness of organic carbon addition and pH increase depends on soil properties.

PubMed

Yuan, Chaolei; Fitzpatrick, Rob; Mosley, Luke M; Marschner, Petra

2015-11-15

Sulfuric material is formed upon oxidation of sulfidic material; it is extremely acidic, and therefore, an environmental hazard. One option for increasing pH of sulfuric material may be stimulation of bacterial sulfate reduction. We investigated the effects of organic carbon addition and pH increase on sulfate reduction after re-flooding in ten sulfuric materials with four treatments: control, pH increase to 5.5 (+pH), organic carbon addition with 2% w/w finely ground wheat straw (+C), and organic carbon addition and pH increase (+C+pH). After 36 weeks, in five of the ten soils, only treatment +C+pH significantly increased the concentration of reduced inorganic sulfur (RIS) compared to the control and increased the soil pore water pH compared to treatment+pH. In four other soils, pH increase or/and organic carbon addition had no significant effect on RIS concentration compared to the control. The RIS concentration in treatment +C+pH as percentage of the control was negatively correlated with soil clay content and initial nitrate concentration. The results suggest that organic carbon addition and pH increase can stimulate sulfate reduction after re-flooding, but the effectiveness of this treatment depends on soil properties. Copyright © 2015 Elsevier B.V. All rights reserved.

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

PubMed

Morgan, M Granger

2007-11-01

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

Cooperative Emissions Trading Game: International Permit Market Dominated by Buyers.

PubMed

Honjo, Keita

2015-01-01

Rapid reduction of anthropogenic greenhouse gas emissions is required to mitigate disastrous impacts of climate change. The Kyoto Protocol introduced international emissions trading (IET) to accelerate the reduction of carbon dioxide (CO2) emissions. The IET controls CO2 emissions through the allocation of marketable emission permits to sovereign countries. The costs for acquiring additional permits provide buyers with an incentive to reduce their CO2 emissions. However, permit price has declined to a low level during the first commitment period (CP1). The downward trend in permit price is attributed to deficiencies of the Kyoto Protocol: weak compliance enforcement, the generous allocation of permits to transition economies (hot air), and the withdrawal of the US. These deficiencies created a buyer's market dominated by price-making buyers. In this paper, I develop a coalitional game of the IET, and demonstrate that permit buyers have dominant bargaining power. In my model, called cooperative emissions trading (CET) game, a buyer purchases permits from sellers only if the buyer forms a coalition with the sellers. Permit price is determined by bargaining among the coalition members. I evaluated the demand-side and supply-side bargaining power (DBP and SBP) using Shapley value, and obtained the following results: (1) Permit price is given by the product of the buyer's willingness-to-pay and the SBP (= 1 - DBP). (2) The DBP is greater than or equal to the SBP. These results indicate that buyers can suppress permit price to low levels through bargaining. The deficiencies of the Kyoto Protocol enhance the DBP, and contribute to the demand-side dominance in the international permit market.

Abiotic CO2 reduction during geologic carbon sequestration facilitated by Fe(II)-bearing minerals

NASA Astrophysics Data System (ADS)

Nielsen, L. C.; Maher, K.; Bird, D. K.; Brown, G. E.; Thomas, B.; Johnson, N. C.; Rosenbauer, R. J.

2012-12-01

Redox reactions involving subsurface minerals and fluids and can lead to the abiotic generation of hydrocarbons from CO2 under certain conditions. Depleted oil reservoirs and saline aquifers targeted for geologic carbon sequestration (GCS) can contain significant quantities of minerals such as ferrous chlorite, which could facilitate the abiotic reduction of carbon dioxide to n-carboxylic acids, hydrocarbons, and amorphous carbon (C0). If such reactions occur, the injection of supercritical CO2 (scCO2) could significantly alter the oxidation state of the reservoir and cause extensive reorganization of the stable mineral assemblage via dissolution and reprecipitation reactions. Naturally occurring iron oxide minerals such as magnetite are known to catalyze CO2 reduction, resulting in the synthesis of organic compounds. Magnetite is thermodynamically stable in Fe(II) chlorite-bearing mineral assemblages typical of some reservoir formations. Thermodynamic calculations demonstrate that GCS reservoirs buffered by the chlorite-kaolinite-carbonate(siderite/magnesite)-quartz assemblage favor the reduction of CO2 to n-carboxylic acids, hydrocarbons, and C0, although the extent of abiotic CO2 reduction may be kinetically limited. To investigate the rates of abiotic CO2 reduction in the presence of magnetite, we performed batch abiotic CO2 reduction experiments using a Dickson-type rocking hydrothermal apparatus at temperatures (373 K) and pressures (100 bar) within the range of conditions relevant to GCS. Blank experiments containing CO2 and H2 were used to rule out the possibility of catalytic activity of the experimental apparatus. Reaction of brine-suspended magnetite nanoparticles with scCO2 at H2 partial pressures typical of reservoir rocks - up to 100 and 0.1 bars respectively - was used to investigate the kinetics of magnetite-catalyzed abiotic CO2 reduction. Later experiments introducing ferrous chlorite (ripidolite) were carried out to determine the potential for heterogeneous catalysis in GCS systems.

A bio-inspired N-doped porous carbon electrocatalyst with hierarchical superstructure for efficient oxygen reduction reaction

NASA Astrophysics Data System (ADS)

Miao, Yue-E.; Yan, Jiajie; Ouyang, Yue; Lu, Hengyi; Lai, Feili; Wu, Yue; Liu, Tianxi

2018-06-01

The bio-inspired hierarchical "grape cluster" superstructure provides an effective integration of one-dimensional carbon nanofibers (CNF) with isolated carbonaceous nanoparticles into three-dimensional (3D) conductive frameworks for efficient electron and mass transfer. Herein, a 3D N-doped porous carbon electrocatalyst consisting of carbon nanofibers with grape-like N-doped hollow carbon particles (CNF@NC) has been prepared through a simple electrospinning strategy combined with in-situ growth and carbonization processes. Such a bio-inspired hierarchically organized conductive network largely facilitates both the mass diffusion and electron transfer during the oxygen reduction reactions (ORR). Therefore, the metal-free CNF@NC catalyst demonstrates superior catalytic activity with an absolute four-electron transfer mechanism, strong methanol tolerance and good long-term stability towards ORR in alkaline media.

Carbon-doped BN nanosheets for metal-free photoredox catalysis

PubMed Central

Huang, Caijin; Chen, Cheng; Zhang, Mingwen; Lin, Lihua; Ye, Xinxin; Lin, Sen; Antonietti, Markus; Wang, Xinchen

2015-01-01

The generation of sustainable and stable semiconductors for solar energy conversion by photoredox catalysis, for example, light-induced water splitting and carbon dioxide reduction, is a key challenge of modern materials chemistry. Here we present a simple synthesis of a ternary semiconductor, boron carbon nitride, and show that it can catalyse hydrogen or oxygen evolution from water as well as carbon dioxide reduction under visible light illumination. The ternary B–C–N alloy features a delocalized two-dimensional electron system with sp2 carbon incorporated in the h-BN lattice where the bandgap can be adjusted by the amount of incorporated carbon to produce unique functions. Such sustainable photocatalysts made of lightweight elements facilitate the innovative construction of photoredox cascades to utilize solar energy for chemical conversion. PMID:26159752

Reduction of Iron-Oxide-Carbon Composites: Part III. Shrinkage of Composite Pellets during Reduction

NASA Astrophysics Data System (ADS)

Halder, S.; Fruehan, R. J.

2008-12-01

This article involves the evaluation of the volume change of iron-oxide-carbon composite pellets and its implications on reduction kinetics under conditions prevalent in a rotary hearth furnace (RHF) that were simulated in the laboratory. The pellets, in general, were found to shrink considerably during the reduction due to the loss of carbon and oxygen from the system, sintering of the iron-oxide, and formation of a molten slag phase at localized regions inside the pellets due to the presence of binder and coal/wood-charcoal ash at the reduction temperatures. One of the shortcomings of the RHF ironmaking process has been the inability to use multiple layers of composite pellets because of the impediment in heat transport to the lower layers of a multilayer bed. However, pellet shrinkage was found to have a strong effect on the reduction kinetics by virtue of enhancing the external heat transport to the lower layers. The volume change of the different kinds of composite pellets was studied as a function of reduction temperature and time. The estimation of the change in the amount of external heat transport with varying pellet sizes for a particular layer of a multilayer bed was obtained by conducting heat-transfer tests using inert low-carbon steel spheres. It was found that if the pellets of the top layer of the bed shrink by 30 pct, the external heat transfer to the second layer increases by nearly 6 times.

Guidance on the State Fiscal Stabilization Fund Program

ERIC Educational Resources Information Center

US Department of Education, 2009

2009-01-01

The State Fiscal Stabilization Fund Program is a new, one-time appropriation of approximately $48.6 billion that the U.S. Department of Education will award to Governors to help stabilize State and local budgets in order to minimize and avoid reductions in education and other essential services, in exchange for a State's commitment to advance …

75 FR 44734 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-29

... from the State of Nevada containing a commitment to reinstate the existing vapor pressure limit in the...''), which establishes a low Reid vapor pressure (RVP) specification for gasoline sold during the late fall... the vapor pressure requirement and associated CO emissions reductions, and are severable from the rest...

Team approach to care in labor and delivery.

PubMed

Mann, Susan; Pratt, Stephen D

2008-12-01

Changing to a teamwork culture in labor and delivery requires a real commitment. The skills involved can be taught to all healthcare providers. The benefits of a teamwork culture may include improved patient outcomes, less medical errors, and improved patient and staff satisfaction. Malpractice claim reduction may possibly occur through these improved outcomes and better communication with our patients.

40 CFR 63.76 - Review of base year emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Review of base year emissions. 63.76... Governing Compliance Extensions for Early Reductions of Hazardous Air Pollutants § 63.76 Review of base year... approve or disapprove base year emission data submitted in an enforceable commitment under § 63.75 or in a...

40 CFR 63.76 - Review of base year emissions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Review of base year emissions. 63.76... Governing Compliance Extensions for Early Reductions of Hazardous Air Pollutants § 63.76 Review of base year... approve or disapprove base year emission data submitted in an enforceable commitment under § 63.75 or in a...

40 CFR 63.76 - Review of base year emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Review of base year emissions. 63.76... Governing Compliance Extensions for Early Reductions of Hazardous Air Pollutants § 63.76 Review of base year... approve or disapprove base year emission data submitted in an enforceable commitment under § 63.75 or in a...

40 CFR 63.76 - Review of base year emissions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Review of base year emissions. 63.76... Governing Compliance Extensions for Early Reductions of Hazardous Air Pollutants § 63.76 Review of base year... approve or disapprove base year emission data submitted in an enforceable commitment under § 63.75 or in a...

Role of heteroatoms in S, N-codoped nanoporous carbons in CO2 (photo)electrochemical reduction.

PubMed

Bandosz, Teresa; Li, Wanlu

2018-06-19

Thiourea-modified wood-based activated carbons were evaluated as catalysts for CO2 electrochemical reduction reaction (CO2ERR). The materials obtained at 950oC showed a long stability. The results indicated that thiophenic sulfur provides catalytic activity for CO formation. However, it was not as active for CH4 formation as was pyridinic-N. Tafel plots suggested that the nanoporous structure enhanced the kinetics for CO2 reduction. The electric conductivity limited the activity for CO2ERR in the materials modified at 600, 800 and 900oC. The effect of visible light on CO2ERR was also investigated in this study. Upon irradiation, photocurrent was generated, and a current density increased during CO2 reduction process. Combined with a band-gap alignment, the results indicate that thiophenic-S in the carbon matrix contributed to sample's photoactivity in visible light. These species enhance the overall reduction process promoting both hydrogen evolution reaction and CO2 reduction to CO. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Exclusive Ni-N4 Sites Realize Near-Unity CO Selectivity for Electrochemical CO2 Reduction.

PubMed

Li, Xiaogang; Bi, Wentuan; Chen, Minglong; Sun, Yuexiang; Ju, Huanxin; Yan, Wensheng; Zhu, Junfa; Wu, Xiaojun; Chu, Wangsheng; Wu, Changzheng; Xie, Yi

2017-10-25

Electrochemical reduction of carbon dioxide (CO 2 ) to value-added carbon products is a promising approach to reduce CO 2 levels and mitigate the energy crisis. However, poor product selectivity is still a major obstacle to the development of CO 2 reduction. Here we demonstrate exclusive Ni-N 4 sites through a topo-chemical transformation strategy, bringing unprecedentedly high activity and selectivity for CO 2 reduction. Topo-chemical transformation by carbon layer coating successfully ensures preservation of the Ni-N 4 structure to a maximum extent and avoids the agglomeration of Ni atoms to particles, providing abundant active sites for the catalytic reaction. The Ni-N 4 structure exhibits excellent activity for electrochemical reduction of CO 2 with particularly high selectivity, achieving high faradaic efficiency over 90% for CO in the potential range from -0.5 to -0.9 V and gives a maximum faradaic efficiency of 99% at -0.81 V with a current density of 28.6 mA cm -2 . We anticipate exclusive catalytic sites will shed new light on the design of high-efficiency electrocatalysts for CO 2 reduction.

Kinetic study of nickel laterite reduction roasting by palm kernel shell charcoal

NASA Astrophysics Data System (ADS)

Sugiarto, E.; Putera, A. D. P.; Petrus, H. T. B. M.

2017-05-01

Demand to process nickel-bearing laterite ore increase as continuous depletion of high-grade nickel-bearing sulfide ore takes place. Due to its common nickel association with iron, processing nickel laterite ore into nickel pig iron (NPI) has been developed by some industries. However, to achieve satisfying nickel recoveries, the process needs massive high-grade metallurgical coke consumption. Concerning on the sustainability of coke supply and positive carbon emission, reduction of nickel laterite ore using biomass-based reductor was being studied.In this study, saprolitic nickel laterite ore was being reduced by palm kernel shell charcoal at several temperatures (800-1000 °C). Variation of biomass-laterite composition was also conducted to study the reduction mechanism. X-ray diffraction and gravimetry analysis were applied to justify the phenomenon and predict kinetic model of the reduction. Results of this study provide information that palm kernel shell charcoal has similar reducing result compared with the conventional method. Reduction, however, was carried out by carbon monoxide rather than solid carbon. Regarding kinetics, Ginstling-Brouhnstein kinetic model provides satisfying results to predict the reduction phenomenon.

Operando spectroscopy study of the carbon dioxide electro-reduction by iron species on nitrogen-doped carbon.

PubMed

Genovese, Chiara; Schuster, Manfred E; Gibson, Emma K; Gianolio, Diego; Posligua, Victor; Grau-Crespo, Ricardo; Cibin, Giannantonio; Wells, Peter P; Garai, Debi; Solokha, Vladyslav; Krick Calderon, Sandra; Velasco-Velez, Juan J; Ampelli, Claudio; Perathoner, Siglinda; Held, Georg; Centi, Gabriele; Arrigo, Rosa

2018-03-05

The carbon-carbon coupling via electrochemical reduction of carbon dioxide represents the biggest challenge for using this route as platform for chemicals synthesis. Here we show that nanostructured iron (III) oxyhydroxide on nitrogen-doped carbon enables high Faraday efficiency (97.4%) and selectivity to acetic acid (61%) at very-low potential (-0.5 V vs silver/silver chloride). Using a combination of electron microscopy, operando X-ray spectroscopy techniques and density functional theory simulations, we correlate the activity to acetic acid at this potential to the formation of nitrogen-coordinated iron (II) sites as single atoms or polyatomic species at the interface between iron oxyhydroxide and the nitrogen-doped carbon. The evolution of hydrogen is correlated to the formation of metallic iron and observed as dominant reaction path over iron oxyhydroxide on oxygen-doped carbon in the overall range of negative potential investigated, whereas over iron oxyhydroxide on nitrogen-doped carbon it becomes important only at more negative potentials.

Carbon Offsets and Renewable Energy Certificates | Climate Neutral Research

Science.gov Websites

Campuses | NREL Carbon Offsets and Renewable Energy Certificates Carbon Offsets and Renewable Energy Certificates Carbon offsets are typically less expensive than installing hardware or undertaking climate reduction targets. While research campuses should not rely on carbon offsets long term, they can

On the Significance of a Carbon-Rich Background in Plasma-Based Graphene Oxide Reduction

DTIC Science & Technology

2016-06-02

can lead to the formation of defects and vacancies. We find that methane provides not only hydrogen but also the carbon necessary to restore the...Graphene oxide Reduction Plasma Argon Hydrogen Methane Office of Naval Research One Liberty Center 875 North Randolph Street, Suite 1425 Arlington, VA...electron-beam generated plasmas produced in argon/ methane (Ar/CH4) backgrounds. However, unlike other reduction approaches [14] the process was found to

Continuous Reductive Amination of Biomass-Derived Molecules over Carbonized Filter Paper-Supported FeNi Alloy.

PubMed

Chieffi, Gianpaolo; Braun, Max; Esposito, Davide

2015-11-01

This paper reports the continuous reductive amination of different molecules, including biomass-related compounds, over carbon-supported FeNi nanoparticles obtained on the basis of inexpensive and abundant metal precursors and cellulose. A biorefinery case study for the preparation of pyrrolidones via acid-catalyzed hydrolysis of glucose followed by reductive amination of the obtained levulinic acid is described. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Iron and manganese in anaerobic respiration: environmental significance, physiology, and regulation

NASA Technical Reports Server (NTRS)

Nealson, K. H.; Saffarini, D.

1994-01-01

Dissimilatory iron and/or manganese reduction is known to occur in several organisms, including anaerobic sulfur-reducing organisms such as Geobacter metallireducens or Desulfuromonas acetoxidans, and facultative aerobes such as Shewanella putrefaciens. These bacteria couple both carbon oxidation and growth to the reduction of these metals, and inhibitor and competition experiments suggest that Mn(IV) and Fe(III) are efficient electron acceptors similar to nitrate in redox abilities and capable of out-competing electron acceptors of lower potential, such as sulfate (sulfate reduction) or CO2 (methanogenesis). Field studies of iron and/or manganese reduction suggest that organisms with such metabolic abilities play important roles in coupling the oxidation of organic carbon to metal reduction under anaerobic conditions. Because both iron and manganese oxides are solids or colloids, they tend to settle downward in aquatic environments, providing a physical mechanism for the movement of oxidizing potential into anoxic zones. The resulting biogeochemical metal cycles have a strong impact on many other elements including carbon, sulfur, phosphorous, and trace metals.

Synthesis of an efficient heteroatom-doped carbon electro-catalyst for oxygen reduction reaction by pyrolysis of protein-rich pulse flour cooked with SiO2 nanoparticles.

PubMed

Gokhale, Rohan; Unni, Sreekuttan M; Puthusseri, Dhanya; Kurungot, Sreekumar; Ogale, Satishchandra

2014-03-07

Development of a highly durable, fuel-tolerant, metal-free electro-catalyst for oxygen reduction reaction (ORR) is essential for robust and cost-effective Anion Exchange Membrane Fuel Cells (AEMFCs). Herein, we report the development of a nitrogen-doped (N-doped) hierarchically porous carbon-based efficient ORR electrocatalyst from protein-rich pulses. The process involves 3D silica nanoparticle templating of the pulse flour(s) followed by their double pyrolysis. The detailed experiments are performed on gram flour (derived from chickpeas) without any in situ/ex situ addition of dopants. The N-doped porous carbon thus generated shows remarkable electrocatalytic activity towards ORR in the alkaline medium. The oxygen reduction on this material follows the desired 4-electron transfer mechanism involving the direct reduction pathway. Additionally, the synthesized carbon catalyst also exhibits good electrochemical stability and fuel tolerance. The results are also obtained and compared with the case of soybean flour having higher nitrogen content to highlight the significance of different parameters in the ORR catalyst performance.

Metal-Organic-Framework-Derived Dual Metal- and Nitrogen-Doped Carbon as Efficient and Robust Oxygen Reduction Reaction Catalysts for Microbial Fuel Cells.

PubMed

Tang, Haolin; Cai, Shichang; Xie, Shilei; Wang, Zhengbang; Tong, Yexiang; Pan, Mu; Lu, Xihong

2016-02-01

A new class of dual metal and N doped carbon catalysts with well-defined porous structure derived from metal-organic frameworks (MOFs) has been developed as a high-performance electrocatalyst for oxygen reduction reaction (ORR). Furthermore, the microbial fuel cell (MFC) device based on the as-prepared Ni/Co and N codoped carbon as air cathode catalyst achieves a maximum power density of 4335.6 mW m -2 and excellent durability.

Self-Assembled Fe-N-Doped Carbon Nanotube Aerogels with Single-Atom Catalyst Feature as High-Efficiency Oxygen Reduction Electrocatalysts

DOE PAGES

Zhu, Chengzhou; Fu, Shaofang; Song, Junhua; ...

2017-02-06

In this study, self-assembled M–N-doped carbon nanotube aerogels with single-atom catalyst feature are for the first time reported through one-step hydrothermal route and subsequent facile annealing treatment. By taking advantage of the porous nanostructures, 1D nanotubes as well as single-atom catalyst feature, the resultant Fe–N-doped carbon nanotube aerogels exhibit excellent oxygen reduction reaction electrocatalytic performance even better than commercial Pt/C in alkaline solution.

Assessing the 100-Year Climate Change Mitigation Potential of Large-Scale Tropical Forest Restoration Under the Bonn Challenge

NASA Astrophysics Data System (ADS)

Wheeler, C. E.; Mitchard, E. T.; Lewis, S. L.

2017-12-01

Restoring degraded and deforested tropical lands to sequester carbon is widely considered to offer substantial climate change mitigation opportunities, if conducted over large spatial scales. Despite this assertion, explicit estimates of how much carbon could be sequestered because of large-scale restoration are rare and have large uncertainties. This is principally due to the many different characteristics of land available for restoration, and different potential restoration activities, which together cause very different rates of carbon sequestration. For different restoration pathways: natural regeneration of degraded and secondary forest, timber plantations and agroforestry, we estimate carbon sequestration rates from the published literature. Then based on tropical restoration commitments made under the Bonn challenge and using carbon density maps, these carbon sequestration rates were used to predict total pan-tropical carbon sequestration to 2100. Restoration of degraded or secondary forest via natural regeneration offers the greatest carbon sequestration potential, considerably exceeding the carbon captured by either timber plantations or agroforestry. This is predominantly due to naturally regenerating forests representing a more permanent store of carbon in comparison to timber plantations and agroforestry land-use options, which, due to their rotational nature, result in the sequential return of carbon to the atmosphere. If the Bonn Challenge is to achieve its ambition of providing substantial climate change mitigation from restoration it must incorporate large areas of natural regeneration back to an intact forest state, otherwise it stands to be a missed opportunity in helping meet the Paris climate change goals.

Photocatalytic CO 2 Reduction by Trigonal-Bipyramidal Cobalt(II) Polypyridyl Complexes: The Nature of Cobalt(I) and Cobalt(0) Complexes upon Their Reactions with CO 2, CO, or Proton

DOE PAGES

Shimoda, Tomoe; Morishima, Takeshi; Kodama, Koichi; ...

2018-04-26

Trigonal-bipyramidal Co(II) complexes are used for photochemical carbon dioxide (CO 2) reduction with Ru(bpy) 3 2+ as a photosensitizer, tri-p-tolylamine (TTA) as a reversible quencher, and triethylamine (TEA) as a sacrificial electron donor to produce carbon monoxide and dihydrogen. Here, the CO 2 reduction is slow because of the large structural changes, spin flipping in the cobalt catalytic intermediates, and an uphill reaction for reduction to catalytically active Co(0) by the photoproduced [Ru(bpy) 3] +.

Photocatalytic CO 2 Reduction by Trigonal-Bipyramidal Cobalt(II) Polypyridyl Complexes: The Nature of Cobalt(I) and Cobalt(0) Complexes upon Their Reactions with CO 2, CO, or Proton

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

Shimoda, Tomoe; Morishima, Takeshi; Kodama, Koichi

Trigonal-bipyramidal Co(II) complexes are used for photochemical carbon dioxide (CO 2) reduction with Ru(bpy) 3 2+ as a photosensitizer, tri-p-tolylamine (TTA) as a reversible quencher, and triethylamine (TEA) as a sacrificial electron donor to produce carbon monoxide and dihydrogen. Here, the CO 2 reduction is slow because of the large structural changes, spin flipping in the cobalt catalytic intermediates, and an uphill reaction for reduction to catalytically active Co(0) by the photoproduced [Ru(bpy) 3] +.

The impacts of electricity dispatch protocols on the emission reductions due to wind power and carbon tax.

PubMed

Yu, Yang; Rajagopal, Ram

2015-02-17

Two dispatch protocols have been adopted by electricity markets to deal with the uncertainty of wind power but the effects of the selection between the dispatch protocols have not been comprehensively analyzed. We establish a framework to compare the impacts of adopting different dispatch protocols on the efficacy of using wind power and implementing a carbon tax to reduce emissions. We suggest that a market has high potential to achieve greater emission reduction by adopting the stochastic dispatch protocol instead of the static protocol when the wind energy in the market is highly uncertain or the market has enough adjustable generators, such as gas-fired combustion generators. Furthermore, the carbon-tax policy is more cost-efficient for reducing CO2 emission when the market operates according to the stochastic protocol rather than the static protocol. An empirical study, which is calibrated according to the data from the Electric Reliability Council of Texas market, confirms that using wind energy in the Texas market results in a 12% CO2 emission reduction when the market uses the stochastic dispatch protocol instead of the 8% emission reduction associated with the static protocol. In addition, if a 6$/ton carbon tax is implemented in the Texas market operated according to the stochastic protocol, the CO2 emission is similar to the emission level from the same market with a 16$/ton carbon tax operated according to the static protocol. Correspondingly, the 16$/ton carbon tax associated with the static protocol costs 42.6% more than the 6$/ton carbon tax associated with the stochastic protocol.

Environment and economic risk: An analysis of carbon emission market and portfolio management.

PubMed

Luo, Cuicui; Wu, Desheng

2016-08-01

Climate change has been one of the biggest and most controversial environmental issues of our times. It affects the global economy, environment and human health. Many researchers find that carbon dioxide (CO2) has contributed the most to climate change between 1750 and 2005. In this study, the orthogonal GARCH (OGARCH) model is applied to examine the time-varying correlations in European CO2 allowance, crude oil and stock markets in US, Europe and China during the Protocol's first commitment period. The results show that the correlations between EUA carbon spot price and the equity markets are higher and more volatile in US and Europe than in China. Then the optimal portfolios consisting these five time series are selected by Mean-Variance and Mean-CVAR models. It shows that the optimal portfolio selected by MV-OGARCH model has the best performance. Copyright © 2016 Elsevier Inc. All rights reserved.

An international comparative overview on the rehabilitation of offenders and effective measures for the prevention of recidivism.

PubMed

Someda, Kei

2009-04-01

The prevention of recidivism has long been a central issue in criminal justice policy. This is justified because an offender who repeatedly commits crime inflicts far greater damage on society than an offender who commits a crime just once in his/her lifetime. For instance, research by the Ministry of Justice of Japan (2007) reveals that only approximately 30% of repeat offenders were responsible for around 60% of the crime committed in Japan from 1948 to 2006. It has been proven that the realization of the rehabilitation of offenders contributes to the reduction of recidivism. The successful rehabilitation of offenders depends in large part upon the effectiveness of the community-based treatment given to offenders based upon an appropriate assessment of multidimensional risk factors and a multidisciplinary approach. In exploring effective community-based treatment of offenders using a multidisciplinary approach, the author touches upon several effective programs from an international comparative view, including: intensive supervision probation/parole (ISP), Drug Court, cognitive behavioral treatment programs and some recent developments related to this field in Japan.

Metal-Free Carbon Materials for CO2 Electrochemical Reduction.

PubMed

Duan, Xiaochuan; Xu, Jiantie; Wei, Zengxi; Ma, Jianmin; Guo, Shaojun; Wang, Shuangyin; Liu, Huakun; Dou, Shixue

2017-11-01

The rapid increase of the CO 2 concentration in the Earth's atmosphere has resulted in numerous environmental issues, such as global warming, ocean acidification, melting of the polar ice, rising sea level, and extinction of species. To search for suitable and capable catalytic systems for CO 2 conversion, electrochemical reduction of CO 2 (CO 2 RR) holds great promise. Emerging heterogeneous carbon materials have been considered as promising metal-free electrocatalysts for the CO 2 RR, owing to their abundant natural resources, tailorable porous structures, resistance to acids and bases, high-temperature stability, and environmental friendliness. They exhibit remarkable CO 2 RR properties, including catalytic activity, long durability, and high selectivity. Here, various carbon materials (e.g., carbon fibers, carbon nanotubes, graphene, diamond, nanoporous carbon, and graphene dots) with heteroatom doping (e.g., N, S, and B) that can be used as metal-free catalysts for the CO 2 RR are highlighted. Recent advances regarding the identification of active sites for the CO 2 RR and the pathway of reduction of CO 2 to the final product are comprehensively reviewed. Additionally, the emerging challenges and some perspectives on the development of heteroatom-doped carbon materials as metal-free electrocatalysts for the CO 2 RR are included. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reduction of CO2 emission by INCAM model in Malaysia biomass power plants during the year 2016.

PubMed

Amin, Nor Aishah Saidina; Talebian-Kiakalaieh, Amin

2018-03-01

As the world's second largest palm oil producer and exporter, Malaysia could capitalize on its oil palm biomass waste for power generation. The emission factors from this renewable energy source are far lower than that of fossil fuels. This study applies an integrated carbon accounting and mitigation (INCAM) model to calculate the amount of CO 2 emissions from two biomass thermal power plants. The CO 2 emissions released from biomass plants utilizing empty fruit bunch (EFB) and palm oil mill effluent (POME), as alternative fuels for powering steam and gas turbines, were determined using the INCAM model. Each section emitting CO 2 in the power plant, known as the carbon accounting center (CAC), was measured for its carbon profile (CP) and carbon index (CI). The carbon performance indicator (CPI) included electricity, fuel and water consumption, solid waste and waste-water generation. The carbon emission index (CEI) and carbon emission profile (CEP), based on the total monthly carbon production, were determined across the CPI. Various innovative strategies resulted in a 20%-90% reduction of CO 2 emissions. The implementation of reduction strategies significantly reduced the CO 2 emission levels. Based on the model, utilization of EFB and POME in the facilities could significantly reduce the CO 2 emissions and increase the potential for waste to energy initiatives. Copyright © 2017 Elsevier Ltd. All rights reserved.

Field-scale reduction of PCB bioavailability with activated carbon amendment to river sediments.

PubMed

Beckingham, Barbara; Ghosh, Upal

2011-12-15

Remediation of contaminated sediments remains a technological challenge because traditional approaches do not always achieve risk reduction goals for human health and ecosystem protection and can even be destructive for natural resources. Recent work has shown that uptake of persistent organic pollutants such as polychlorinated biphenyls (PCBs) in the food web is strongly influenced by the nature of contaminant binding, especially to black carbon surfaces in sediments. We demonstrate for the first time in a contaminated river that application of activated carbon to sediments in the field reduces biouptake of PCBs in benthic organisms. After treatment with activated carbon applied at a dose similar to the native organic carbon of sediment, bioaccumulation in freshwater oligochaete worms was reduced compared to preamendment conditions by 69 to 99%, and concentrations of PCBs in water at equilibrium with the sediment were reduced by greater than 93% at all treatment sites for up to three years of monitoring. By comparing measured reductions in bioaccumulation of tetra- and penta-chlorinated PCB congeners resulting from field application of activated carbon to a laboratory study where PCBs were preloaded onto activated carbon, it is evident that equilibrium sorption had not been achieved in the field. Although other remedies may be appropriate for some highly contaminated sites, we show through this pilot study that PCB exposure from moderately contaminated river sediments may be managed effectively through activated carbon amendment in sediments.

Matrix approach to uncertainty assessment and reduction for modeling terrestrial carbon cycle

NASA Astrophysics Data System (ADS)

Luo, Y.; Xia, J.; Ahlström, A.; Zhou, S.; Huang, Y.; Shi, Z.; Wang, Y.; Du, Z.; Lu, X.

2017-12-01

Terrestrial ecosystems absorb approximately 30% of the anthropogenic carbon dioxide emissions. This estimate has been deduced indirectly: combining analyses of atmospheric carbon dioxide concentrations with ocean observations to infer the net terrestrial carbon flux. In contrast, when knowledge about the terrestrial carbon cycle is integrated into different terrestrial carbon models they make widely different predictions. To improve the terrestrial carbon models, we have recently developed a matrix approach to uncertainty assessment and reduction. Specifically, the terrestrial carbon cycle has been commonly represented by a series of carbon balance equations to track carbon influxes into and effluxes out of individual pools in earth system models. This representation matches our understanding of carbon cycle processes well and can be reorganized into one matrix equation without changing any modeled carbon cycle processes and mechanisms. We have developed matrix equations of several global land C cycle models, including CLM3.5, 4.0 and 4.5, CABLE, LPJ-GUESS, and ORCHIDEE. Indeed, the matrix equation is generic and can be applied to other land carbon models. This matrix approach offers a suite of new diagnostic tools, such as the 3-dimensional (3-D) parameter space, traceability analysis, and variance decomposition, for uncertainty analysis. For example, predictions of carbon dynamics with complex land models can be placed in a 3-D parameter space (carbon input, residence time, and storage potential) as a common metric to measure how much model predictions are different. The latter can be traced to its source components by decomposing model predictions to a hierarchy of traceable components. Then, variance decomposition can help attribute the spread in predictions among multiple models to precisely identify sources of uncertainty. The highly uncertain components can be constrained by data as the matrix equation makes data assimilation computationally possible. We will illustrate various applications of this matrix approach to uncertainty assessment and reduction for terrestrial carbon cycle models.

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

O'Shaughnessy, Eric; Heeter, Jenny; Keyser, David

Cities are increasingly taking actions such as building code enforcement, urban planning, and public transit expansion to reduce emissions of carbon dioxide in their communities and municipal operations. However, many cities lack the quantitative information needed to estimate policy impacts and prioritize city actions in terms of carbon abatement potential and cost effectiveness. This report fills this research gap by providing methodologies to assess the carbon abatement potential of a variety of city actions. The methodologies are applied to an energy use data set of 23,458 cities compiled for the U.S. Department of Energy’s City Energy Profile tool. The analysismore » estimates the national carbon abatement potential of the most commonly implemented actions in six specific policy areas. The results of this analysis suggest that, in aggregate, cities could reduce nationwide carbon emissions by about 210 million metric tons of carbon dioxide (MMT CO 2) per year in a "moderate abatement scenario" by 2035 and 480 MMT CO 2/year in a "high abatement scenario" by 2035 through these common actions typically within a city’s control in the six policy areas. The aggregate carbon abatement potential of these specific areas equates to a reduction of 3%-7% relative to 2013 U.S. emissions. At the city level, the results suggest the average city could reduce carbon emissions by 7% (moderate) to 19% (high) relative to current city-level emissions. City carbon abatement potential is sensitive to national and state policies that affect the carbon intensity of electricity and transportation. Specifically, the U.S. Clean Power Plan and further renewable energy cost reductions could reduce city carbon emissions overall, helping cities achieve their carbon reduction goals.« less

Microstructural and Mechanical Properties of Hot Roll Bonded Titanium Alloy/Low Carbon Steel Plate

NASA Astrophysics Data System (ADS)

Yu, Chao; Qi, Zi-chen; Yu, Hui; Xu, Cheng; Xiao, Hong

2018-03-01

In this paper, a titanium alloy and low carbon steel were bonded via hot rolling in a vacuum, and the effect of roll bonding temperature and reduction ratio on the microstructural and mechanical properties of the plate was studied. When the bonding temperature was between 850 and 1050 °C, the shear strength of the interface increased with an increasing reduction ratio from 18 to 70%. At a bonding temperature of 950 °C and at a rolling reduction ratio of 70%, the best bonding strength was obtained, and a shear fracture occurred on the low carbon steel matrix. At 1050 °C, brittle compounds, i.e., TiC, FeTi, and Fe2Ti, formed at the interface, which decreased the bonding strength. The large reduction ratio can break up compounds at the interface and extrude fresh metal for bonding, thereby increasing the bonding strength.

Electrochemical process for the preparation of nitrogen fertilizers

DOEpatents

Aulich, Ted R.; Olson, Edwin S.; Jiang, Junhua

2013-03-19

The present invention provides methods and apparatus for the preparation of nitrogen fertilizers including ammonium nitrate, urea, urea-ammonium nitrate, and/or ammonia utilizing a source of carbon, a source of nitrogen, and/or a source of hydrogen. Implementing an electrolyte serving as ionic charge carrier, (1) ammonium nitrate is produced via the reduction of a nitrogen source at the cathode and the oxidation of a nitrogen source at the anode; (2) urea or its isomers are produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source; (3) ammonia is produced via the reduction of nitrogen source at the cathode and the oxidation of a hydrogen source at the anode; and (4) urea-ammonium nitrate is produced via the simultaneous cathodic reduction of a carbon source and a nitrogen source, and anodic oxidation of a nitrogen source. The electrolyte can be solid.

In vivo assimilation of one-carbon via a synthetic reductive glycine pathway in Escherichia coli.

PubMed

Yishai, Oren; Bouzon, Madeleine; Döring, Volker; Bar-Even, Arren

2018-05-15

Assimilation of one-carbon compounds presents a key biochemical challenge, which limits their use as sustainable feedstocks for microbial growth and production. The reductive glycine pathway is a synthetic metabolic route that could provide an optimal way for the aerobic assimilation of reduced C1 compounds. Here, we show that a rational integration of native and foreign enzymes enables the tetrahydrofolate and glycine cleavage/synthase systems to operate in the reductive direction, such that Escherichia coli satisfies all of its glycine and serine requirements from the assimilation of formate and CO2. Importantly, the biosynthesis of serine from formate and CO2 does not lower the growth rate, indicating high flux that is able to provide 10% of cellular carbon. Our findings assert that the reductive glycine pathway could support highly efficient aerobic assimilation of C1-feedstocks.

Modeling Anaerobic Soil Organic Carbon Decomposition in Arctic Polygon Tundra: Insights into Soil Geochemical Influences on Carbon Mineralization: Modeling Archive

DOE Data Explorer

Zheng, Jianqiu; Thornton, Peter; Painter, Scott; Gu, Baohua; Wullschleger, Stan; Graham, David

2018-06-13

This anaerobic carbon decomposition model is developed with explicit representation of fermentation, methanogenesis and iron reduction by combining three well-known modeling approaches developed in different disciplines. A pool-based model to represent upstream carbon transformations and replenishment of DOC pool, a thermodynamically-based model to calculate rate kinetics and biomass growth for methanogenesis and Fe(III) reduction, and a humic ion-binding model for aqueous phase speciation and pH calculation are implemented into the open source geochemical model PHREEQC (V3.0). Installation of PHREEQC is required to run this model.

Fabrication of biomembrane-like films on carbon electrodes using alkanethiol and diazonium salt and their application for direct electrochemistry of myoglobin.

PubMed

Anjum, Saima; Qi, Wenjing; Gao, Wenyue; Zhao, Jianming; Hanif, Saima; Aziz-Ur-Rehman; Xu, Guobao

2015-03-15

Alkanethiols generally form self-assembled monolayers on gold electrodes and the electrochemical reduction of aromatic diazonium salts is a popular method for the covalent modification of carbon. Based on the reaction of alkanethiol with aldehyde groups covalently bound on carbon surface by the electrochemical reduction of aromatic diazonium salts, a new strategy for the modification of carbon electrodes with alkanethiols has been developed. The modification of carbon surface with aldehyde groups is achieved by the electrochemical reduction of aromatic diazonium salts in situ electrogenerated from a nitro precursor, p-nitrophenylaldehyde, in the presence of nitrous acid. By this way, in situ electrogenerated p-aminophenyl aldehyde from p-nitrophenylaldehyde immediately reacts with nitrous acid, effectively minimizing the side reaction of amine groups and aldehyde groups. The as-prepared alkanethiol-modified glassy carbon electrode was further used to make biomembrane-like films by casting didodecyldimethylammonium bromide on its surface. The biomembrane-like films enable the direct electrochemistry of immobilized myoglobin for the detection of hydrogen peroxide. The response is linear over the range of 1-600μM with a detection limit of 0.3μM. Copyright © 2014 Elsevier B.V. All rights reserved.

Application of gas diffusion biocathode in microbial electrosynthesis from carbon dioxide.

PubMed

Bajracharya, Suman; Vanbroekhoven, Karolien; Buisman, Cees J N; Pant, Deepak; Strik, David P B T B

2016-11-01

Microbial catalysis of carbon dioxide (CO 2 ) reduction to multi-carbon compounds at the cathode is a highly attractive application of microbial electrosynthesis (MES). The microbes reduce CO 2 by either taking the electrons or reducing the equivalents produced at the cathode. While using gaseous CO 2 as the carbon source, the biological reduction process depends on the dissolution and mass transfer of CO 2 in the electrolyte. In order to deal with this issue, a gas diffusion electrode (GDE) was investigated by feeding CO 2 through the GDE into the MES reactor for its reduction at the biocathode. A combination of the catalyst layer (porous activated carbon and Teflon binder) and the hydrophobic gas diffusion layer (GDL) creates a three-phase interface at the electrode. So, CO 2 and reducing equivalents will be available to the biocatalyst on the cathode surface. An enriched inoculum consisting of acetogenic bacteria, prepared from an anaerobic sludge, was used as a biocatalyst. The cathode potential was maintained at -1.1 V vs Ag/AgCl to facilitate direct and/or hydrogen-mediated CO 2 reduction. Bioelectrochemical CO 2 reduction mainly produced acetate but also extended the products to ethanol and butyrate. Average acetate production rates of 32 and 61 mg/L/day, respectively, with 20 and 80 % CO 2 gas mixture feed were achieved with 10 cm 2 of GDE. The maximum acetate production rate remained 238 mg/L/day for 20 % CO 2 gas mixture. In conclusion, a gas diffusion biocathode supported bioelectrochemical CO 2 reduction with enhanced mass transfer rate at continuous supply of gaseous CO 2 . Graphical abstract ᅟ.

Highly regenerable carbon-Fe3O4 core-satellite nanospheres as oxygen reduction electrocatalyst and magnetic adsorbent

NASA Astrophysics Data System (ADS)

Zhou, Wenqiang; Liu, Minmin; Cai, Chao; Zhou, Haijun; Liu, Rui

2017-02-01

We present the synthesis and multifunctional utilization of core-satellite carbon-Fe3O4 nanoparticles to serve as the enabling platform for a range of applications including oxygen reduction reaction (ORR) and magnetic adsorbent. Starting from polydopamine (PDA) nanoparticles and Fe(NO3)3, carbon-Fe3O4 core-satellite nanospheres are synthesized through successive steps of impregnation, ammoniation and carbonization. The synergistic combination of Fe3O4 and N-doped carbon endows the nanocomposite with high electrochemical activity in ORR and mainly four electrons transferred in reaction process. Furthermore, carbon-Fe3O4 nanoparticles used as magnetic adsorbent exhibit the efficient removal of Rhodamine B from an aqueous solution. The recovery and reuse of the adsorbent is demonstrated 5 times without any detectible loss in activity.

Reducing black carbon emissions from diesel vehicles in Russia: An assessment and policy recommendations

DOE PAGES

Kholod, Nazar; Evans, Meredydd

2015-11-13

This article assesses options and challenges of reducing black carbon emissions from diesel vehicles in Russia. Black carbon is a product of incomplete diesel combustion and is a component of fine particulate matter. Particulate matter emissions have adverse health impacts, causing cardiopulmonary disease and lung cancer; black carbon is also a large climate forcer. Black carbon emissions from Russian diesel sources affect not only the Russian territory but also contribute to overall pollution. Here, this paper analyzes current ecological standards for vehicles and fuel, evaluates policies for emission reductions from existing diesel vehicle fleet, and assesses Russia’s attempts to encouragemore » the use of natural gas as a vehicle fuel. Based on best practices of black carbon emission reductions, this paper provides a number of policy recommendations for Russia.« less

Reducing black carbon emissions from diesel vehicles in Russia: An assessment and policy recommendations

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

Kholod, Nazar; Evans, Meredydd

This article assesses options and challenges of reducing black carbon emissions from diesel vehicles in Russia. Black carbon is a product of incomplete diesel combustion and is a component of fine particulate matter. Particulate matter emissions have adverse health impacts, causing cardiopulmonary disease and lung cancer; black carbon is also a large climate forcer. Black carbon emissions from Russian diesel sources affect not only the Russian territory but also contribute to overall pollution. Here, this paper analyzes current ecological standards for vehicles and fuel, evaluates policies for emission reductions from existing diesel vehicle fleet, and assesses Russia’s attempts to encouragemore » the use of natural gas as a vehicle fuel. Based on best practices of black carbon emission reductions, this paper provides a number of policy recommendations for Russia.« less

Geochemical Impacts to Groundwater from Geologic Carbon Sequestration: Controls on pH and Inorganic Carbon Concentrations from Reaction Path and Kinetic Modeling

EPA Science Inventory

Geologic carbon sequestration has the potential to cause long-term reductions in global emissions of carbon dioxide to the atmosphere. Safe and effective application of carbon sequestration technology requires an understanding of the potential risks to the quality of underground...

Epidemiological transition of some diseases in Oman: a situational analysis.

PubMed

Ganguly, S S; Al-Shafaee, M A; Al-Lawati, J A; Dutta, P K; Duttagupta, K K

2009-01-01

During the past 35 years Oman has undergone a rapid socioeconomic and epidemiological transition leading to a steep reduction in child and adult mortality and morbidity due to the decline of various communicable diseases, including vaccine-preventable diseases. Good governance and planning, together with leadership and commitment by the government, has been a critical factor in this reduction. However, with increasing prosperity, lifestyle-related noncommunicable diseases have emerged as new health challenges to the country, with cardiovascular diseases, diabetes and obesity in the lead among other chronic conditions. Appropriate prevention strategies for reducing the burden of noncommunicable diseases are discussed.

Equilibrium responses of global net primary production and carbon storage to doubled atmospheric carbon dioxide: Sensitivity to changes in vegetation nitrogen concentration

USGS Publications Warehouse

McGuire, David A.; Melillo, J.M.; Kicklighter, D.W.; Pan, Y.; Xiao, X.; Helfrich, J.; Moore, B.; Vorosmarty, C.J.; Schloss, A.L.

1997-01-01

We ran the terrestrial ecosystem model (TEM) for the globe at 0.5?? resolution for atmospheric CO2 concentrations of 340 and 680 parts per million by volume (ppmv) to evaluate global and regional responses of net primary production (NPP) and carbon storage to elevated CO2 for their sensitivity to changes in vegetation nitrogen concentration. At 340 ppmv, TEM estimated global NPP of 49.0 1015 g (Pg) C yr-1 and global total carbon storage of 1701.8 Pg C; the estimate of total carbon storage does not include the carbon content of inert soil organic matter. For the reference simulation in which doubled atmospheric CO2 was accompanied with no change in vegetation nitrogen concentration, global NPP increased 4.1 Pg C yr-1 (8.3%), and global total carbon storage increased 114.2 Pg C. To examine sensitivity in the global responses of NPP and carbon storage to decreases in the nitrogen concentration of vegetation, we compared doubled CO2 responses of the reference TEM to simulations in which the vegetation nitrogen concentration was reduced without influencing decomposition dynamics ("lower N" simulations) and to simulations in which reductions in vegetation nitrogen concentration influence decomposition dynamics ("lower N+D" simulations). We conducted three lower N simulations and three lower N+D simulations in which we reduced the nitrogen concentration of vegetation by 7,5, 15.0, and 22.5%. In the lower N simulations, the response of global NPP to doubled atmospheric CO2 increased approximately 2 Pg C yr-1 for each incremental 7.5% reduction in vegetation nitrogen concentration, and vegetation carbon increased approximately an additional 40 Pg C, and soil carbon increased an additional 30 Pg C, for a total carbon storage increase of approximately 70 Pg C. In the lower N+D simulations, the responses of NPP and vegetation carbon storage were relatively insensitive to differences in the reduction of nitrogen concentration, but soil carbon storage showed a large change. The insensitivity of NPP in the N+D simulations occurred because potential enhancements in NPP associated with reduced vegetation nitrogen concentration were approximately offset by lower nitrogen availability associated with the decomposition dynamics of reduced litter nitrogen concentration. For each 7.5% reduction in vegetation nitrogen concentration, soil carbon increased approximately an additional 60 Pg C, while vegetation carbon storage increased by only approximately 5 Pg C. As the reduction in vegetation nitrogen concentration gets greater in the lower N+D simulations, more of the additional carbon storage tends to become concentrated in the north temperateboreal region in comparison to the tropics. Other studies with TEM show that elevated CO2 more than offsets the effects of climate change to cause increased carbon storage. The results of this study indicate that carbon storage would be enhanced by the influence of changes in plant nitrogen concentration on carbon assimilation and decomposition rates. Thus changes in vegetation nitrogen concentration may have important implications for the ability of the terrestrial biosphere to mitigate increases in the atmospheric concentration of CO2 and climate changes associated with the increases.

A System of Systems Approach to the EU Energy System

NASA Astrophysics Data System (ADS)

Jess, Tom; Madani, Kaveh; Mahlooji, Maral; Ristic, Bora

2016-04-01

Around the world, measures to prevent dangerous climate change are being adopted and may change energy systems fundamentally. The European Union (EU) is committed to reducing greenhouse gas emission by 20% by 2020 and by 80-95% by 2050. In order to achieve this, EU member states aim to increase the share of renewables in the energy mix to 20% by 2020. This commitment comes as part of a series of other aims, principles, and policies to reform the EU's energy system. Cost-efficiency in the emissions reductions measures as well as strategic goals under the Resource Efficient Europe flagship initiative which would include a more prudent approach to other natural resources such as water and land. Using the "System of Systems Approach", as from Hadian and Madani (2015), energy sources' Relative Aggregate Footprints (RAF) in the EU are evaluated. RAF aggregates across four criteria: carbon footprint, water footprint, land footprint, and economic cost. The four criteria are weighted by resource availability across the EU and for each Member State. This provides an evaluation of the overall resource use efficiency of the EU's energy portfolio and gives insight into the differences in the desirability of energy sources across Member States. Broadly, nuclear, onshore wind, and geothermal are most desirable under equal criteria weights and EU average weighting introduces only small changes in the relative performance of only few technologies. The member state specific weightings show that most countries have similar energy technology preferences. However, the UK deviates most strongly from the average, with an even stronger preference for nuclear and coal. Sweden, Malta and Finland also deviate from the typical preferences indicating the complexity in play in reforming the EU energy system. Reference Hadian S, Madani K (2015) A System of Systems Approach to Energy Sustainability Assessment: Are All Renewables Really Green? Ecological Indicators, 52, 194-206.

Carbon dioxide reduction through urban forestry: guidelines for professional and volunteer tree planters

Treesearch

E. Gregory McPherson; James R. Simpson

1999-01-01

Carbon dioxide reduction through urban forestry—Guidelines for professional and volunteer tree planters has been developed by the Pacific Southwest Research Station’s Western Center for Urban Forest Research and Education as a tool for utilities, urban foresters and arborists, municipalities, consultants, non-profit organizations and others to...

REDUCTIVE DEHALOGENATION OF HEXACHLOROETHANE, CARBON TETRACHLORIDE, AND BROMOFORM BY ANTHRAHYDROQUINONE DISULFONATE AND HUMIC ACID

EPA Science Inventory

The reductive dehalogenation of hexachloroethane (CzCLj), carbon tetrachloride (CC14), and bromoform (CHBr3) was examined at 50 “C in aqueous solutions containing ei- ther (1) 500 pM of 2,6-anthrahydroquinone disulfonate (AHQDS), (2) 250 pM Fe2+, or (3) 250 pM HS-. The pH ranged ...

Public Constructs of Energy Values and Behaviors in Implementing Taiwan's "Energy-Conservation/Carbon-Reduction" Declarations

ERIC Educational Resources Information Center

Chiu, Mei-Shiu; Yeh, Huei-Ming; Spangler, Jonathan

2016-01-01

The emergent crisis of global warming calls for energy education for people of all ages and social groups. The Taiwanese government has publicized 10 declarations on energy conservation and carbon reduction as public behavior guidelines to mitigate global warming. This study uses interviews with quantitative assessment to explore the values and…

Preparation and Study on Nickel Oxide Reduction of Polyacrylonitrile-Based Carbon Nanofibers by Thermal Treatment.

PubMed

Lee, Yeong Ju; Kim, Hyun Bin; Jeun, Joon Pyo; Lee, Dae Soo; Koo, Dong Hyun; Kang, Phil Hyun

2015-08-01

Carbon materials containing magnetic nanopowder have been attractive in technological applications such as electrochemical capacitors and electromagnetic wave shielding. In this study, polyacrylonitrile (PAN) fibers containing nickel nanoparticles were prepared using an electrospinning method and thermal stabilization. The reduction of nickel oxide was investigated under a nitrogen atmosphere within a temperature range of 600 to 1,000 °C. Carbon nanofibers containing nickel nanoparticles were characterized by FE-SEM, EDS, XRD, TGA, and VSM. It was found that nickel nanoparticles were formed by a NiO reduction in PAN as a function of the thermal treatment. These results led to an increase in the coercivity of nanofibers and a decrease in the remanence magnetization.

The effect of tar spot pathogen on host plant carbon balance and its possible consequences on a tundra ecosystem.

PubMed

Masumoto, Shota; Uchida, Masaki; Tojo, Motoaki; Herrero, Maria Luz; Mori, Akira S; Imura, Satoshi

2018-03-01

In Arctic tundra, plant pathogens have substantial effects on the growth and survival of hosts, and impacts on the carbon balance at the scale of ecological systems. To understand these effects on carbon dynamics across different scales including plant organ, individual, population and ecosystem, we focused on two primary factors: host productivity reduction and carbon consumption by the pathogen. We measured the effect of the pathogen on photosynthetic and respiratory activity in the host. We also measured respiration and the amount of carbon in the pathogen. We constructed a model based on these two factors, and calculated pathogenic effects on the carbon balance at different organismal and ecological scales. We found that carbon was reduced in infected leaves by 118% compared with healthy leaves; the major factor causing this loss was pathogenic carbon consumption. The carbon balance at the population and ecosystem levels decreased by 35% and 20%, respectively, at an infection rate of 30%. This case study provides the first evidence that a host plant can lose more carbon through pathogenic carbon consumption than through a reduction in productivity. Such a pathogenic effect could greatly change ecosystem carbon cycling without decreasing annual productivity.

Evaluation of in situ layers for treatment of acid mine drainage: a field comparison.

PubMed

Hulshof, Andrea H M; Blowes, David W; Gould, W Douglas

2006-05-01

Reactive treatment layers, containing labile organic carbon, were evaluated to determine their ability to promote sulfate reduction and metal sulfide precipitation within a tailings impoundment, thereby treating tailings effluent prior to discharge. Organic carbon materials, including woodchips and pulp waste, were mixed with the upper meter of tailings in two separate test cells, a third control cell contained only tailings. In the woodchip cell sulfate reduction rates were 500 mg L-1a-1, (5.2 mmol L-1a-1) this was coupled with the gradual removal of 350 mg L-1 Zn (5.4 mmol L-1). Decreased delta13CDIC values from -3 per thousand to as low as -12 per thousand indicated that sulfate reduction was coupled with organic carbon oxidation. In the pulp waste cell the most dramatic change was observed near the interface between the pulp waste amended tailings and the underlying undisturbed tailings. Sulfate reduction rates were 5000 mg L-1a-1 (52 mmol L-1a-1), Fe concentrations decreased by 80-99.5% (148 mmol L-1) and Zn was consistently <5 mg L-1. Rates of sulfate reduction and metal removal decreased as the pore water migrated upward into the shallower tailings. Increased rates of sulfate reduction in the pulp waste cell were consistent with decreased delta13CDIC values, to as low as -22 per thousand, and increased populations of sulfate reducing bacteria. Lower concentrations of the nutrients, phosphorus, organic carbon and nitrogen in the woodchip material contribute to the lower sulfate reduction rates observed in the woodchip cell.

A modified carbothermal reduction method for preparation of high-performance nano-scale core/shell Cu 6Sn 5 alloy anodes in Li-ion batteries

NASA Astrophysics Data System (ADS)

Cui, Wangjun; Wang, Fei; Wang, Jie; Liu, Haijing; Wang, Congxiao; Xia, Yongyao

Core-shell structured, carbon-coated, nano-scale Cu 6Sn 5 has been prepared by a modified carbothermal reduction method using polymer coated mixed oxides of CuO and SnO 2 as precursors. On heat treatment, the mixture oxides were converted into Cu 6Sn 5 alloy by carbothermal reduction. Simultaneously, the remnants carbon was coated on the surface of the Cu 6Sn 5 particles to form a core-shell structure. Transmission electron microscope (TEM) images demonstrate that the well-coated carbon layer effectively prevents the encapsulated, low melting point alloy from out flowing in a high-temperature treatment process. Core-shell structured, carbon coated Cu 6Sn 5 delivers a reversible capacity of 420 mAh g -1 with capacity retention of 80% after 50 cycles. The improvement in the cycling ability can be attributed to the fact that the carbon-shell prevents aggregation and pulverization of nano-sized tin-based alloy particles during charge/discharge cycling.

Tradespace and Affordability - Phase 1

DTIC Science & Technology

2013-07-09

assessment options Cost-effectiveness, risk reduction leverage/ROI, rework avoidance Tool, data, scenario availability Contract Number: H98230-08-D-0171...Prepare FED assessment plans and earned value milestones Try to relate earned value to risk -exposure avoided rather than budgeted cost F. Begin...evaluate and iterate plans and enablers I. Assess readiness for Commitment Review Shortfalls identified as risks and covered by risk mitigation

Establish Time for Learning: Finding Time to Collaborate Takes Creativity and Commitment

ERIC Educational Resources Information Center

Killion, Joellen

2016-01-01

The major challenge with time is finding it. Current school-day schedules and school-year calendars are leaner than ever because of budget reductions. States and districts have implemented furlough days to balance lean-and-mean budgets that show no sign of improving. Few are willing to take the leap toward reducing instructional time to improve…

A Review of New Labour's Policy on School Exclusion: The Political Challenge of School Disaffection in England

ERIC Educational Resources Information Center

Reed, Jodie

2003-01-01

Shortly after coming to power, Tony Blair's New Labour government expressed its strong commitment to tackling the problem of school expulsion. The Treasury's 1998 Spending Review included the bold target to achieve "a reduction by one third in... exclusions (from 12,500 to 8,400 permanent exclusions a year) by 2002". This article gives…

Reducing the Federal Budget: Strategies and Examples, Fiscal Years 1982- 1986.

DTIC Science & Technology

1981-02-01

Small issues are being used with increasing frequency to finance a wide range of facilities including manufacturing plants, fast- food franchises , and...Funding for Amtrak .......... 79 Phasing Out of Conrail Funding ........ 81 Reduction in New Subway Commitments ...... ... 83 Reduced Spending on...Grant ............... 166 Changes in Food Stamp Program . . . . . . . 168 Recoupment of Food Stamp Benefits . . . . .. 171 Change in the Low Income

A "Carbon Reduction Challenge" as tool for undergraduate engagement on climate change

NASA Astrophysics Data System (ADS)

Cobb, K. M.; Toktay, B.

2017-12-01

Institutions of higher education must meet the challenges of educating the generation that must make significant progress towards stabilizing atmospheric greenhouse gases. However, the interdisciplinary nature of the climate change problem, and the fact that solutions will necessarily involve manipulating natural systems, advancing energy technologies, and developing innovative policy instruments means that traditional disciplinary tracks are not well-suited for the task. Furthermore, institutions must not only equip students with fundamental knowledge about climate and energy, but they must empower a generation of students to become part of the climate change solution. Here we present the cumulative results of the `Carbon Reduction Challenge' - a team-based competition to reduce CO2 that is conducted in an interdisciplinary undergraduate class called "Energy, the Environment, and Society" at Georgia Institute of Technology. Working with 30 undergraduate students from all years and all majors, we demonstrate how student teams move through a highly-structured timeline of deliverables towards achieving their team's end-of-semester goals. We discuss the importance of student creativity, ingenuity, initiative, and perseverance in achieving project outcomes, which in 2017 topped 5 million pounds of CO2 reductions - the all-time record for the class. Student-driven reductions on a year-to-year basis track an exponential growth curve through time. Based on the success of a pilot Carbon Reduction Challenge conducted in the summer of 2017, we present evidence that student-led partnerships with large corporations represents the area of largest potential for student success. Such partnerships deliver significant value added to students (professional conduct, on-the-job training, networking), the corporate partner (cost savings, talent recruitment, and public relations), and to the higher education institution (corporate relations contacts). In summary, the Carbon Reduction Challenge represents a solutions-oriented, hands-on, project-based learning tool that has achieved significant pedagogical benefits while delivering real-world carbon reductions and cost savings to community stakeholders.

State Constitutional Commitment to Health and Health Care and Population Health Outcomes: Evidence From Historical US Data

PubMed Central

2015-01-01

Objectives. I investigated whether the introduction of health and health care provisions in US state constitutions can make health systems more equitable and improve health outcomes by urging state policymakers and administrative agencies to uphold their human rights obligations at state level. Methods. I constructed a panel of infant mortality rates from 50 US states over the period 1929 through 2000 to examine their association with the timing and details of introducing a constitutional right to health and health care provisions. Results. The introduction of a stronger constitutional commitment that obligates state legislature to provide health care was associated with a subsequent reduction in the infant mortality rate of approximately 7.8%. The introduction of provisions explicitly targeting the poor was also associated with a reduction in the infant mortality rate of 6.5%. These health benefits are primarily evident in non-White populations. Conclusions. This empirical result supports Elizabeth Leonard’s view that although state constitutional rights have been poorly enforced through the judiciary, a constitutional expression of health care duties has fueled the political and social process, ultimately allowing states to identify the best way to address citizens’ health inequality concerns. PMID:25905857

Drug error in paediatric anaesthesia: current status and where to go now.

PubMed

Anderson, Brian J

2018-06-01

Medication errors in paediatric anaesthesia and the perioperative setting continue to occur despite widespread recognition of the problem and published advice for reduction of this predicament at international, national, local and individual levels. Current literature was reviewed to ascertain drug error rates and to appraise causes and proposed solutions to reduce these errors. The medication error incidence remains high. There is documentation of reduction through identification of causes with consequent education and application of safety analytics and quality improvement programs in anaesthesia departments. Children remain at higher risk than adults because of additional complexities such as drug dose calculations, increased susceptibility to some adverse effects and changes associated with growth and maturation. Major improvements are best made through institutional system changes rather than a commitment to do better on the part of each practitioner. Medication errors in paediatric anaesthesia represent an important risk to children and most are avoidable. There is now an understanding of the genesis of adverse drug events and this understanding should facilitate the implementation of known effective countermeasures. An institution-wide commitment and strategy are the basis for a worthwhile and sustained improvement in medication safety.

State constitutional commitment to health and health care and population health outcomes: evidence from historical US data.

PubMed

Matsuura, Hiroaki

2015-07-01

I investigated whether the introduction of health and health care provisions in US state constitutions can make health systems more equitable and improve health outcomes by urging state policymakers and administrative agencies to uphold their human rights obligations at state level. I constructed a panel of infant mortality rates from 50 US states over the period 1929 through 2000 to examine their association with the timing and details of introducing a constitutional right to health and health care provisions. The introduction of a stronger constitutional commitment that obligates state legislature to provide health care was associated with a subsequent reduction in the infant mortality rate of approximately 7.8%. The introduction of provisions explicitly targeting the poor was also associated with a reduction in the infant mortality rate of 6.5%. These health benefits are primarily evident in non-White populations. This empirical result supports Elizabeth Leonard's view that although state constitutional rights have been poorly enforced through the judiciary, a constitutional expression of health care duties has fueled the political and social process, ultimately allowing states to identify the best way to address citizens' health inequality concerns.

High chance that current atmospheric greenhouse concentrations commit to warmings greater than 1.5 °C over land.

PubMed

Huntingford, Chris; Mercado, Lina M

2016-07-27

The recent Paris UNFCCC climate meeting discussed the possibility of limiting global warming to 2 °C since pre-industrial times, or possibly even 1.5 °C, which would require major future emissions reductions. However, even if climate is stabilised at current atmospheric greenhouse gas (GHG) concentrations, those warming targets would almost certainly be surpassed in the context of mean temperature increases over land only. The reason for this is two-fold. First, current transient warming lags significantly below equilibrium or "committed" warming. Second, almost all climate models indicate warming rates over land are much higher than those for the oceans. We demonstrate this potential for high eventual temperatures over land, even for contemporary GHG levels, using a large set of climate models and for which climate sensitivities are known. Such additional land warming has implications for impacts on terrestrial ecosystems and human well-being. This suggests that even if massive and near-immediate emissions reductions occur such that atmospheric GHGs increase further by only small amounts, careful planning is needed by society to prepare for higher land temperatures in an eventual equilibrium climatic state.

Air quality co-benefits of subnational carbon policies

DOE PAGES

Thompson, Tammy M.; Rausch, Sebastian; Saari, Rebecca K.; ...

2016-05-18

To mitigate climate change, governments ranging from city to multi-national have adopted greenhouse gas (GHG) emissions reduction targets. While the location of GHG reductions does not affect their climate benefits, it can impact human health benefits associated with co-emitted pollutants. Here, an advanced modeling framework is used to explore how subnational level GHG targets influence air pollutant co-benefits from ground level ozone and fine particulate matter. Two carbon policy scenarios are analyzed, each reducing the same total amount of GHG emissions in the Northeast US: an economy-wide Cap and Trade (CAT) program reducing emissions from all sectors of the economy,more » and a Clean Energy Standard (CES) reducing emissions from the electricity sector only. Results suggest that a regional CES policy will cost about 10 times more than a CAT policy. Despite having the same regional targets in the Northeast, carbon leakage to non-capped regions varies between policies. Consequently, a regional CAT policy will result in national carbon reductions that are over six times greater than the carbon reduced by the CES in 2030. Monetized regional human health benefits of the CAT and CES policies are 844% and 185% of the costs of each policy, respectively. Benefits for both policies are thus estimated to exceed their costs in the Northeast US. The estimated value of human health co-benefits associated with air pollution reductions for the CES scenario is two times that of the CAT scenario. Implications: In this research, an advanced modeling framework is used to determine the potential impacts of regional carbon policies on air pollution co-benefits associated with ground level ozone and fine particulate matter. Study results show that spatially heterogeneous GHG policies have the potential to create areas of air pollution dis-benefit. It is also shown that monetized human health benefits within the area covered by policy may be larger than the model estimated cost of the policy. These findings are of particular interest both as U.S. states work to develop plans to meet state-level carbon emissions reduction targets set by the EPA through the Clean Power Plan, and in the absence of comprehensive national carbon policy.« less

Air quality co-benefits of subnational carbon policies.

PubMed

Thompson, Tammy M; Rausch, Sebastian; Saari, Rebecca K; Selin, Noelle E

2016-10-01

To mitigate climate change, governments ranging from city to multi-national have adopted greenhouse gas (GHG) emissions reduction targets. While the location of GHG reductions does not affect their climate benefits, it can impact human health benefits associated with co-emitted pollutants. Here, an advanced modeling framework is used to explore how subnational level GHG targets influence air pollutant co-benefits from ground level ozone and fine particulate matter. Two carbon policy scenarios are analyzed, each reducing the same total amount of GHG emissions in the Northeast US: an economy-wide Cap and Trade (CAT) program reducing emissions from all sectors of the economy, and a Clean Energy Standard (CES) reducing emissions from the electricity sector only. Results suggest that a regional CES policy will cost about 10 times more than a CAT policy. Despite having the same regional targets in the Northeast, carbon leakage to non-capped regions varies between policies. Consequently, a regional CAT policy will result in national carbon reductions that are over six times greater than the carbon reduced by the CES in 2030. Monetized regional human health benefits of the CAT and CES policies are 844% and 185% of the costs of each policy, respectively. Benefits for both policies are thus estimated to exceed their costs in the Northeast US. The estimated value of human health co-benefits associated with air pollution reductions for the CES scenario is two times that of the CAT scenario. In this research, an advanced modeling framework is used to determine the potential impacts of regional carbon policies on air pollution co-benefits associated with ground level ozone and fine particulate matter. Study results show that spatially heterogeneous GHG policies have the potential to create areas of air pollution dis-benefit. It is also shown that monetized human health benefits within the area covered by policy may be larger than the model estimated cost of the policy. These findings are of particular interest both as U.S. states work to develop plans to meet state-level carbon emissions reduction targets set by the EPA through the Clean Power Plan, and in the absence of comprehensive national carbon policy.

Disentangling the contribution of multiple land covers to fire-mediated carbon emissions in Amazonia during the 2010 drought.

PubMed

Anderson, Liana Oighenstein; Aragão, Luiz E O C; Gloor, Manuel; Arai, Egídio; Adami, Marcos; Saatchi, Sassan S; Malhi, Yadvinder; Shimabukuro, Yosio E; Barlow, Jos; Berenguer, Erika; Duarte, Valdete

2015-10-01

In less than 15 years, the Amazon region experienced three major droughts. Links between droughts and fires have been demonstrated for the 1997/1998, 2005, and 2010 droughts. In 2010, emissions of 510 ± 120 Tg C were associated to fire alone in Amazonia. Existing approaches have, however, not yet disentangled the proportional contribution of multiple land cover sources to this total. We develop a novel integration of multisensor and multitemporal satellite-derived data on land cover, active fires, and burned area and an empirical model of fire-induced biomass loss to quantify the extent of burned areas and resulting biomass loss for multiple land covers in Mato Grosso (MT) state, southern Amazonia-the 2010 drought most impacted region. We show that 10.77% (96,855 km 2 ) of MT burned. We estimated a gross carbon emission of 56.21 ± 22.5 Tg C from direct combustion of biomass, with an additional 29.4 ± 10 Tg C committed to be emitted in the following years due to dead wood decay. It is estimated that old-growth forest fires in the whole Brazilian Legal Amazon (BLA) have contributed to 14.81 Tg of C (11.75 Tg C to 17.87 Tg C) emissions to the atmosphere during the 2010 fire season, with an affected area of 27,555 km 2 . Total C loss from the 2010 fires in MT state and old-growth forest fires in the BLA represent, respectively, 77% (47% to 107%) and 86% (68.2% to 103%) of Brazil's National Plan on Climate Change annual target for Amazonia C emission reductions from deforestation.

Carbon recovery rates following different wildfire risk mitigation treatments

Treesearch

M. Hurteau; M. North

2010-01-01

Sequestered forest carbon can provide a climate change mitigation benefit, but in dry temperate forests, wildfire poses a reversal risk to carbon offset projects. Reducing wildfire risk requires a reduction in and redistribution of carbon stocks, the benefit of which is only realized when wildfire occurs. To estimate the time needed to recover carbon removed and...

Estimating litter carbon stocks on forest land in the United States

Treesearch

Grant M. Domke; Charles H. (Hobie) Perry; Brian F. Walters; Christopher W. Woodall; Matthew B. Russell; James E. Smith

2016-01-01

Forest ecosystems are the largest terrestrial carbon sink on earth, withmore than half of their net primary productionmoving to the soil via the decomposition of litter biomass. Therefore, changes in the litter carbon (C) pool have important implications for global carbon budgets and carbon emissions reduction targets and negotiations. Litter accounts for an estimated...

Regioselective electrochemical reduction of 2,4-dichlorobiphenyl - Distinct standard reduction potentials for carbon-chlorine bonds using convolution potential sweep voltammetry

NASA Astrophysics Data System (ADS)

Muthukrishnan, A.; Sangaranarayanan, M. V.; Boyarskiy, V. P.; Boyarskaya, I. A.

2010-04-01

The reductive cleavage of carbon-chlorine bonds in 2,4-dichlorobiphenyl (PCB-7) is investigated using the convolution potential sweep voltammetry and quantum chemical calculations. The potential dependence of the logarithmic rate constant is non-linear which indicates the validity of Marcus-Hush theory of quadratic activation-driving force relationship. The ortho-chlorine of the 2,4-dichlorobiphenyl gets reduced first as inferred from the quantum chemical calculations and bulk electrolysis. The standard reduction potentials pertaining to the ortho-chlorine of 2,4-dichlorobiphenyl and that corresponding to para chlorine of the 4-chlorobiphenyl have been estimated.

Noncovalent immobilization of electrocatalysts on carbon electrodes for fuel production.

PubMed

Blakemore, James D; Gupta, Ayush; Warren, Jeffrey J; Brunschwig, Bruce S; Gray, Harry B

2013-12-11

We show that molecular catalysts for fuel-forming reactions can be immobilized on graphitic carbon electrode surfaces via noncovalent interactions. A pyrene-appended bipyridine ligand (P) serves as the linker between each complex and the surface. Immobilization of a rhodium proton-reduction catalyst, [Cp*Rh(P)Cl]Cl (1), and a rhenium CO2-reduction catalyst, Re(P)(CO)3Cl (2), afford electrocatalytically active assemblies. X-ray photoelectron spectroscopy and electrochemistry confirm catalyst immobilization. Reduction of 1 in the presence of p-toluenesulfonic acid results in catalytic H2 production, while reduction of 2 in the presence of CO2 results in catalytic CO production.

Nitro Lignin-Derived Nitrogen-Doped Carbon as an Efficient and Sustainable Electrocatalyst for Oxygen Reduction.

PubMed

Graglia, Micaela; Pampel, Jonas; Hantke, Tina; Fellinger, Tim-Patrick; Esposito, Davide

2016-04-26

The use of lignin as a precursor for the synthesis of materials is nowadays considered very interesting from a sustainability standpoint. Here we illustrate the synthesis of a micro-, meso-, and macroporous nitrogen-doped carbon (NDC) using lignin extracted from beech wood via alkaline hydrothermal treatment and successively functionalized via aromatic nitration. The so obtained material is thus carbonized in the eutectic salt melt KCl/ZnCl2. The final NDC shows an excellent activity as electrocatalyst for the oxygen reduction reaction.

Comment on "Carbon farming in hot, dry coastal areas: an option for climate change mitigation" by Becker et al. (2013)

NASA Astrophysics Data System (ADS)

Heimann, M.

2014-01-01

Becker et al. (2013) argue that an afforestation of 0.73 × 109 ha with Jatropha curcas plants would generate an additional terrestrial carbon sink of 4.3 PgC yr-1, enough to stabilise the atmospheric mixing ratio of carbon dioxide (CO2) at current levels. However, this is not consistent with the dynamics of the global carbon cycle. Using a well-established global carbon cycle model, the effect of adding such a hypothetical sink leads to a reduction of atmospheric CO2 levels in the year 2030 by 25 ppm compared to a reference scenario. However, the stabilisation of the atmospheric CO2 concentration requires a much larger additional sink or corresponding reduction of anthropogenic emissions.

Comment on "Carbon farming in hot, dry coastal areas: an option for climate change mitigation" by Becker et al. (2013)

NASA Astrophysics Data System (ADS)

Heimann, M.

2013-08-01

Becker et al. (2013) argue that an afforestation of 0.73 109 ha with Jatropha curcas plants would generate an additional terrestrial carbon sink of 4.3 PgC yr-1, enough to stabilise the atmospheric mixing ratio of carbon dioxide (CO2) at current levels. However, this is not consistent with the dynamics of the global carbon cycle. Using a well established global carbon cycle model, the effect of adding such a hypothetical sink leads to a reduction of atmospheric CO2 levels in the year 2030 by 25 ppm compared to a reference scenario. However, the stabilisation of the atmospheric CO2 concentration requires a much larger additional sink or corresponding reduction of anthropogenic emissions.

Abiotic reduction of trifluralin and pendimethalin by sulfides in black-carbon-amended coastal sediments.

PubMed

Gong, Wenwen; Liu, Xinhui; Xia, Shuhua; Liang, Baocui; Zhang, Wei

2016-06-05

Dinitroaniline herbicides such as trifluralin and pendimethalin are persistent bioaccumulative toxins to aquatic organisms. Thus, in-situ remediation of contaminated sediments is desired. This study investigated whether black carbons (BCs), including apple wood charcoal (BC1), rice straw biochar (BC2), and activated carbon (BC3), could facilitate abiotic reduction of trifluralin and pendimethalin by sulfides of environmentally-relevant concentrations in anoxic coastal sediments. The reduction rates of trifluralin and pendimethalin increased substantially with increasing BC dosages in the sediments. This enhancing effect was dependent on BC type with the greatest for BC3 followed by BC1 and BC2, which well correlated with their specific surface area. The pseudo-first order reduction rate constants (kobs) for BC3-amended sediment (2%) were 13- and 14 times the rate constants in the BC-free sediment. The reduction rates increased with increasing temperature from 8 to 25°C in the BC-amended sediment, following the Arrhenius relationship. Finally, through molecular modeling by density functional theory and reaction species identification from mass spectra, molecular pathways of trifluralin and pendimethalin reduction were elucidated. In contrary to the separate sequential reduction of each nitro group to amine group, both nitro groups, first reduced to nitroso, then eventually to amine groups. Copyright © 2016 Elsevier B.V. All rights reserved.

Incorporating operational flexibility into electric generation planning Impacts and methods for system design and policy analysis

NASA Astrophysics Data System (ADS)

Palmintier, Bryan S.

This dissertation demonstrates how flexibility in hourly electricity operations can impact long-term planning and analysis for future power systems, particularly those with substantial variable renewables (e.g., wind) or strict carbon policies. Operational flexibility describes a power system's ability to respond to predictable and unexpected changes in generation or demand. Planning and policy models have traditionally not directly captured the technical operating constraints that determine operational flexibility. However, as demonstrated in this dissertation, this capability becomes increasingly important with the greater flexibility required by significant renewables (>= 20%) and the decreased flexibility inherent in some low-carbon generation technologies. Incorporating flexibility can significantly change optimal generation and energy mixes, lower system costs, improve policy impact estimates, and enable system designs capable of meeting strict regulatory targets. Methodologically, this work presents a new clustered formulation that tractably combines a range of normally distinct power system models, from hourly unit-commitment operations to long-term generation planning. This formulation groups similar generators into clusters to reduce problem size, while still retaining the individual unit constraints required to accurately capture operating reserves and other flexibility drivers. In comparisons against traditional unit commitment formulations, errors were generally less than 1% while run times decreased by several orders of magnitude (e.g., 5000x). Extensive numerical simulations, using a realistic Texas-based power system show that ignoring flexibility can underestimate carbon emissions by 50% or result in significant load and wind shedding to meet environmental regulations. Contributions of this dissertation include: 1. Demonstrating that operational flexibility can have an important impact on power system planning, and describing when and how these impacts occur; 2. Demonstrating that a failure to account for operational flexibility can result in undesirable outcomes for both utility planners and policy analysts; and 3. Extending the state of the art for electric power system models by introducing a tractable method for incorporating unit commitment based operational flexibility at full 876o hourly resolution directly into planning optimization. Together these results encourage and offer a new flexibility-aware approach for capacity planning and accompanying policy design that can enable cleaner, less expensive electric power systems for the future. (Copies available exclusively from MIT Libraries, libraries.mit.edu/docs - docs mit.edu)

Assembling of carbon nanotubes film responding to significant reduction wear and friction on steel surface

NASA Astrophysics Data System (ADS)

Zhang, Bin; Xue, Yong; Qiang, Li; Gao, Kaixong; Liu, Qiao; Yang, Baoping; Liang, Aiming; Zhang, Junyan

2017-11-01

Friction properties of carbon nanotubes have been widely studied and reported, however, the friction properties of carbon nanotubes related on state of itself. It is showing superlubricity under nanoscale, but indicates high shear adhesion as aligned carbon nanotube film. However, friction properties under high load (which is commonly in industry) of carbon nanotube films are seldom reported. In this paper, carbon nanotube films, via mechanical rubbing method, were obtained and its tribology properties were investigated at high load of 5 to 15 N. Though different couple pairs were employed, the friction coefficients of carbon nanotube films are nearly the same. Compared with bare stainless steel, friction coefficients and wear rates under carbon nanotube films lubrication reduced to, at least, 1/5 and 1/(4.3-14.5), respectively. Friction test as well as structure study were carried out to reveal the mechanism of the significant reduction wear and friction on steel surface. One can conclude that sliding and densifying of carbon nanotubes at sliding interface contribute to the sufficient decrease of friction coefficients and wear rates.

ASSESSMENT OF HOUSEHOLD CARBON FOOTPRINT REDUCTION POTENTIALS

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

Kramer, Klaas Jan; Homan, Greg; Brown, Rich

2009-04-15

The term ?household carbon footprint? refers to the total annual carbon emissions associated with household consumption of energy, goods, and services. In this project, Lawrence Berkeley National Laboratory developed a carbon footprint modeling framework that characterizes the key underlying technologies and processes that contribute to household carbon footprints in California and the United States. The approach breaks down the carbon footprint by 35 different household fuel end uses and 32 different supply chain fuel end uses. This level of end use detail allows energy and policy analysts to better understand the underlying technologies and processes contributing to the carbon footprintmore » of California households. The modeling framework was applied to estimate the annual home energy and supply chain carbon footprints of a prototypical California household. A preliminary assessment of parameter uncertainty associated with key model input data was also conducted. To illustrate the policy-relevance of this modeling framework, a case study was conducted that analyzed the achievable carbon footprint reductions associated with the adoption of energy efficient household and supply chain technologies.« less

Environmental Aspects of Use of Recycled Carbon Fiber Composites in Automotive Applications.

PubMed

Meng, Fanran; McKechnie, Jon; Turner, Thomas; Wong, Kok H; Pickering, Stephen J

2017-11-07

The high cost and energy intensity of virgin carbon fiber manufacture provides an opportunity to recover substantial value from carbon fiber reinforced plastic wastes. In this study, we assess the life cycle environmental implications of recovering carbon fiber and producing composite materials as substitutes for conventional and proposed lightweight materials in automotive applications (e.g., steel, aluminum, virgin carbon fiber). Key parameters for the recycled carbon fiber materials, including fiber volume fraction and fiber alignment, are investigated to identify beneficial uses of recycled carbon fiber in the automotive sector. Recycled carbon fiber components can achieve the lowest life cycle environmental impacts of all materials considered, although the actual impact is highly dependent on the design criteria (λ value) of the specific component. Low production impacts associated with recycled carbon fiber components are observed relative to lightweight competitor materials (e.g., aluminum, virgin carbon fiber reinforced plastic). In addition, recycled carbon fiber components have low in-use energy use due to mass reductions and associated reduction in mass-induced fuel consumption. The results demonstrate environmental feasibility of the CFRP recycling materials, supporting the emerging commercialization of CF recycling technologies and identifying significant potential market opportunities in the automotive sector.

Operationalizing clean development mechanism baselines: A case study of China's electrical sector

NASA Astrophysics Data System (ADS)

Steenhof, Paul A.

The global carbon market is rapidly developing as the first commitment period of the Kyoto Protocol draws closer and Parties to the Protocol with greenhouse gas (GHG) emission reduction targets seek alternative ways to reduce their emissions. The Protocol includes the Clean Development Mechanism (CDM), a tool that encourages project-based investments to be made in developing nations that will lead to an additional reduction in emissions. Due to China's economic size and rate of growth, technological characteristics, and its reliance on coal, it contains a large proportion of the global CDM potential. As China's economy modernizes, more technologies and processes are requiring electricity and demand for this energy source is accelerating rapidly. Relatively inefficient technology to generate electricity in China thereby results in the electrical sector having substantial GHG emission reduction opportunities as related to the CDM. In order to ensure the credibility of the CDM in leading to a reduction in GHG emissions, it is important that the baseline method used in the CDM approval process is scientifically sound and accessible for both others to use and for evaluation purposes. Three different methods for assessing CDM baselines and environmental additionality are investigated in the context of China's electrical sector: a method based on a historical perspective of the electrical sector (factor decomposition), a method structured upon a current perspective (operating and build margins), and a simulation of the future (dispatch analysis). Assessing future emission levels for China's electrical sector is a very challenging task given the complexity of the system, its dynamics, and that it is heavily influenced by internal and external forces, but of the different baseline methods investigated, dispatch modelling is best suited for the Chinese context as it is able to consider the important regional and temporal dimensions of its economy and its future development. For China, the most promising options for promoting sustainable development, one of the goals of the Kyoto Protocol, appear to be tied to increasing electrical end-use and generation efficiency, particularly clean coal technology for electricity generation since coal will likely continue to be a dominant primary fuel.

Reduction of Iron-Oxide-Carbon Composites: Part I. Estimation of the Rate Constants

NASA Astrophysics Data System (ADS)

Halder, S.; Fruehan, R. J.

2008-12-01

A new ironmaking concept using iron-oxide-carbon composite pellets has been proposed, which involves the combination of a rotary hearth furnace (RHF) and an iron bath smelter. This part of the research focuses on studying the two primary chemical kinetic steps. Efforts have been made to experimentally measure the kinetics of the carbon gasification by CO2 and wüstite reduction by CO by isolating them from the influence of heat- and mass-transport steps. A combined reaction model was used to interpret the experimental data and determine the rate constants. Results showed that the reduction is likely to be influenced by the chemical kinetics of both carbon oxidation and wüstite reduction at the temperatures of interest. Devolatilized wood-charcoal was observed to be a far more reactive form of carbon in comparison to coal-char. Sintering of the iron-oxide at the high temperatures of interest was found to exert a considerable influence on the reactivity of wüstite by virtue of altering the internal pore surface area available for the reaction. Sintering was found to be predominant for highly porous oxides and less of an influence on the denser ores. It was found using an indirect measurement technique that the rate constants for wüstite reduction were higher for the porous iron-oxide than dense hematite ore at higher temperatures (>1423 K). Such an indirect mode of measurement was used to minimize the influence of sintering of the porous oxide at these temperatures.

Nafion induced surface confinement of oxygen in carbon-supported oxygen reduction catalysts

DOE PAGES

Chlistunoff, Jerzy; Sansinena, Jose -Maria

2016-11-17

We studied the surface confinement of oxygen inside layers of Nafion self-assembled on carbon-supported oxygen reduction reaction (ORR) catalysts. It is demonstrated that oxygen accumulates in the hydrophobic component of the polymer remaining in contact with the carbon surface. Furthermore, the amount of surface confined oxygen increases with the degree of carbon surface graphitization, which promotes the self-assembly of the polymer. Planar macrocyclic ORR catalysts possessing a delocalized system of π electrons such as Co and Fe porphyrins and phthalocyanines have virtually no effect on the surface confinement of oxygen, in accordance with their structural similarity to graphitic carbon surfacesmore » where they adsorb. Platinum particles in carbon-supported ORR catalysts with high metal contents (20%) disrupt the self-assembly of Nafion and virtually eliminate the oxygen confinement, but the phenomenon is still observed for low Pt loading (4.8%) catalysts.« less

Nafion induced surface confinement of oxygen in carbon-supported oxygen reduction catalysts

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

Chlistunoff, Jerzy; Sansinena, Jose -Maria

We studied the surface confinement of oxygen inside layers of Nafion self-assembled on carbon-supported oxygen reduction reaction (ORR) catalysts. It is demonstrated that oxygen accumulates in the hydrophobic component of the polymer remaining in contact with the carbon surface. Furthermore, the amount of surface confined oxygen increases with the degree of carbon surface graphitization, which promotes the self-assembly of the polymer. Planar macrocyclic ORR catalysts possessing a delocalized system of π electrons such as Co and Fe porphyrins and phthalocyanines have virtually no effect on the surface confinement of oxygen, in accordance with their structural similarity to graphitic carbon surfacesmore » where they adsorb. Platinum particles in carbon-supported ORR catalysts with high metal contents (20%) disrupt the self-assembly of Nafion and virtually eliminate the oxygen confinement, but the phenomenon is still observed for low Pt loading (4.8%) catalysts.« less

Heavily Graphitic-Nitrogen Self-doped High-porosity Carbon for the Electrocatalysis of Oxygen Reduction Reaction

NASA Astrophysics Data System (ADS)

Feng, Tong; Liao, Wenli; Li, Zhongbin; Sun, Lingtao; Shi, Dongping; Guo, Chaozhong; Huang, Yu; Wang, Yi; Cheng, Jing; Li, Yanrong; Diao, Qizhi

2017-11-01

Large-scale production of active and stable porous carbon catalysts for oxygen reduction reaction (ORR) from protein-rich biomass became a hot topic in fuel cell technology. Here, we report a facile strategy for synthesis of nitrogen-doped porous nanocarbons by means of a simple two-step pyrolysis process combined with the activation of zinc chloride and acid-treatment process, in which kidney bean via low-temperature carbonization was preferentially adopted as the only carbon-nitrogen sources. The results show that this carbon material exhibits excellent ORR electrocatalytic activity, and higher durability and methanol-tolerant property compared to the state-of-the-art Pt/C catalyst for the ORR, which can be mainly attributed to high graphitic-nitrogen content, high specific surface area, and porous characteristics. Our results can encourage the synthesis of high-performance carbon-based ORR electrocatalysts derived from widely-existed natural biomass.

Climate change reduces the capacity of northern peatlands to absorb the atmospheric carbon dioxide: The different responses of bogs and fens

NASA Astrophysics Data System (ADS)

Wu, Jianghua; Roulet, Nigel T.

2014-10-01

The carbon (C) storage of northern peatlands is equivalent to ~34-46% of the ~795 T g C currently held in the atmosphere as CO2. Most studies report that northern peatlands are a sink of between 20 and 60 g CO2-C m-2 yr-1. Since peatland hydrology and biogeochemistry are very closely related to climate, there is concern whether northern peatlands will continue to function as C sinks with climate change. We used a coupled land surface scheme and peatland C model, called CLASS3W-MWM, to examine the sensitivity of peatland C to climate change. Based on the data available to constrain our model, we simulated the C dynamics of the Mer Bleue (MB) bog in eastern Canada and the Degerö Stormyr (DS) poor fen in northern Sweden for four Intergovernmental Panel on Climate Change (IPCC) climate change scenarios, i.e., A1B, A2, B1, and Commit, over four time periods, i.e., present day, 2030, 2060, and 2100. When the simulated future C fluxes were compared to the baseline fluxes under the present climate conditions, we found that fens were much more sensitive to climate change than bogs. Gross primary production (GPP) at MB significantly increased by 4-44% up to 2100 for all scenarios except Commit. GPP at DS significantly decreased by 34-39% for A1B and A2, and slightly increased by 6-10% for B1 and Commit. Total ecosystem respiration (TER) significantly increased by 7-57% for MB and 4-34% for DS up to 2100 for all scenarios except Commit. Net ecosystem production (NEP), therefore, significantly decreased. The bog, however, was still a C sink up to 2100, though much reduced, but the fen switched to a C source for A1B and A2 scenarios. Additional experiments where we climatically transplanted the study peatlands or forced vegetation changes when the fen became too dry showed similar but less dramatic results as the standard runs. Our results indicate that northern peatlands should be included in the C-coupled climate model to fully understand the response of C cycling in terrestrial ecosystems to climate change and to reduce the uncertainties for projecting the future climate.

The anaerobic degradation of organic matter in Danish coastal sediments - Iron reduction, manganese reduction, and sulfate reduction

NASA Technical Reports Server (NTRS)

Canfield, Donald E.; Thamdrup, BO; Hansen, Jens W.

1993-01-01

A combination of porewater and solid phase analysis as well as a series of sediment incubations are used to quantify organic carbon oxidation by dissimilatory Fe reduction, Mn reduction, and sulfate reduction, in sediments from the Skagerrak (located off the northeast coast of Jutland, Denmark). Solid phase data are integrated with incubation results to define the zones of the various oxidation processes. At S(9), surface Mn enrichments of up to 3.5 wt pct were found, and with such a ready source of Mn, dissimilatory Mn reduction was the only significant anaerobic process of carbon oxidation in the surface 10 cm of the sediment. At S(4) and S(6), active Mn reduction occurred; however, most of the Mn reduction may have resulted from the oxidation of acid volatile sulfides and Fe(2+) rather than by a dissimilatory sulfate. Dissolved Mn(2+) was found to completely adsorb onto sediment containing fully oxidized Mn oxides.

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

Nichols, Eva M.; Derrick, Jeffrey S.; Nistanaki, Sepand K.

The development of catalysts for electrochemical reduction of carbon dioxide offers an attractive approach to transforming this greenhouse gas into value-added carbon products with sustainable energy input.

Electrocatalytic CO2 reduction near the theoretical potential in water using Ru complex supported on carbon nanotubes

NASA Astrophysics Data System (ADS)

Sato, Shunsuke; Arai, Takeo; Morikawa, Takeshi

2018-01-01

We successfully developed a highly efficient electrode for CO2 reduction using a Ru-complex catalyst ([Ru]) supported on carbon paper coated with multi-walled carbon nanotubes (CPCNT/[Ru]). The CPCNT/[Ru] electrode promoted the CO2 reduction reaction in aqueous solution near the theoretical potential, and produced formate linearly with a current density of greater than 0.9 mA cm-2 at -0.15 V (versus RHE) for at least 24 h. Due to the outstandingly low overpotential, a monolithic tablet-shaped photo-device was realized by coupling the CPCNT/[Ru] catalyst with amorphous SiGe-jn as a light absorber and IrO x as a water oxidation catalyst, and the device produced formate from CO2 and water in a single-compartment reactor. The nanotubes enhanced the rate for CO2 reduction at [Ru], and accordingly a solar-to-chemical conversion efficiency of 4.3% for formate production was achieved when the CO2 reduction and H2O oxidation sites had the same area.

REDUCTIVE DEHALOGENATION OF HEXACHLOROETHANE, CARBON TETRACHLORIDE, AND BROMOFORM BY ANAHYDROQUINONE DISULFONATE AND HUMIC ACID

EPA Science Inventory

The reductive dehalogenation of hexachloroethane (C2CI6), carbon tetrachloride (CC14), and bromoform (CHBr3) was examined at 50 degrees C in aqueous solutions containing either (1) 500 uM of 2,6-anthrahydroquinone disulfonate (AHQDS), (2) 250 uM Fe2+, or (3) 250 uM HS. The pH ran...

Using augmented reality to inform consumer choice and lower carbon footprints

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

Isley, Steven C.; Ketcham, Robert; Arent, Douglas J.

Consumers who wish to consider product attributes like carbon footprints in their purchasing decisions are often blocked from meaningful action by a lack of information. We conducted a single randomized controlled trial at a grocery store to evaluate the effects of providing such product attribute and carbon footprint information via augmented reality (AR) displays on bottled water and breakfast cereal, two frequently purchased goods. Using an AR smartphone app that incorporates comparative and detailed product information into personalized data and recommendations, a 23% statistically significant reduction in carbon footprint was found for bottled water, and non-significant reductions for breakfast cereal.more » Furthermore, AR informed choice lead to healthier cereal choices.« less

Using augmented reality to inform consumer choice and lower carbon footprints

DOE PAGES

Isley, Steven C.; Ketcham, Robert; Arent, Douglas J.

2017-05-23

Consumers who wish to consider product attributes like carbon footprints in their purchasing decisions are often blocked from meaningful action by a lack of information. We conducted a single randomized controlled trial at a grocery store to evaluate the effects of providing such product attribute and carbon footprint information via augmented reality (AR) displays on bottled water and breakfast cereal, two frequently purchased goods. Using an AR smartphone app that incorporates comparative and detailed product information into personalized data and recommendations, a 23% statistically significant reduction in carbon footprint was found for bottled water, and non-significant reductions for breakfast cereal.more » Furthermore, AR informed choice lead to healthier cereal choices.« less

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

Brauman, A.; Labat, M.; Kane, M.D.

The evolution of different feeding guilds in termites is paralleled by differences in the activity of their gut microbiota. In wood-feeding termites, carbon dioxide-reducing acetogenic bacteria were found to generally outprocess carbon dioxide-reducing methanogenic bacteria for reductant (presumably hydrogen) generated during microbial fermentation in the hindgut. By contrast, acetogenesis from hydrogen and carbon dioxide was of little significance in fungus-growing and soil-feeding termites, which evolved more methane than their wood- and grass-feeding counterparts. Given the large biomass of termites on the earth and especially in the tropics, these findings should help refine global estimates of carbon dioxide reduction in anoxicmore » habitats and the contribution of termite emissions to atmospheric methane concentrations.« less

Identification of a Noroxomaritidine Reductase with Amaryllidaceae Alkaloid Biosynthesis Related Activities*

PubMed Central

Kilgore, Matthew B.; Holland, Cynthia K.; Jez, Joseph M.; Kutchan, Toni M.

2016-01-01

Amaryllidaceae alkaloids are a large group of plant natural products with over 300 documented structures and diverse biological activities. Several groups of Amaryllidaceae alkaloids including the hemanthamine- and crinine-type alkaloids show promise as anticancer agents. Two reduction reactions are required for the production of these compounds: the reduction of norcraugsodine to norbelladine and the reduction of noroxomaritidine to normaritidine, with the enantiomer of noroxomaritidine dictating whether the derivatives will be the crinine-type or hemanthamine-type. It is also possible for the carbon-carbon double bond of noroxomaritidine to be reduced, forming the precursor for maritinamine or elwesine depending on the enantiomer reduced to an oxomaritinamine product. In this study, a short chain alcohol dehydrogenase/reductase that co-expresses with the previously discovered norbelladine 4′-O-methyltransferase from Narcissus sp. and Galanthus spp. was cloned and expressed in Escherichia coli. Biochemical analyses and x-ray crystallography indicates that this protein functions as a noroxomaritidine reductase that forms oxomaritinamine from noroxomaritidine through a carbon-carbon double bond reduction. The enzyme also reduces norcraugsodine to norbelladine with a 400-fold lower specific activity. These studies identify a missing step in the biosynthesis of this pharmacologically important class of plant natural products. PMID:27252378

Carbon and Mo transformations during the synthesis of mesoporous Mo2C/carbon catalysts by carbothermal hydrogen reduction

NASA Astrophysics Data System (ADS)

Wang, Haiyan; Liu, Shida; Liu, Bing; Montes, Vicente; Hill, Josephine M.; Smith, Kevin J.

2018-02-01

The synthesis of mesoporous Mo2C/carbon catalysts by carbothermal hydrogen reduction is reported. Petroleum coke (petcoke) was activated with KOH at 800 °C to obtain high surface area microporous activated petcoke (APC; 2000 m2/g). The APC was wet impregnated with ammonium heptamolybdate (AHM: 10 wt% Mo), dried and reduced in H2 at temperatures from 400 to 800 °C, to yield Mo2C/APC catalysts. Increased reduction temperature increased the Mo2C yield and the mesoporous volume of the Mo2C/APC. At a reduction temperature of 750 °C the mesopore volume of the catalyst doubled compared to the APC support and accounted for 37% of the total pore volume. Maintaining the final CHR temperature for 90 min further increased the Mo2C yield and mesoporosity of the catalyst. The role of Mo2C in the catalytic hydrogenation of the APC and mesopore generation is demonstrated. The activity of the Mo2C/carbon catalysts in the hydrodeoxygenation of 4-methyl phenol increased with increased CHR temperature and catalyst mesoporosity.

Benefits of using biogas technology in rural area: karo district on supporting local action plan for greenhouse gas emission reduction of north sumatera province 2010-2020

NASA Astrophysics Data System (ADS)

Ginting, N.

2017-05-01

Indonesia committed to reduce its greenhouse gas (GHG) by 26% in 2020. At the UNFCCC (Conference of the United Nation Framework Convention on Climate Change) held in Paris in December 2015 Indonesia committed to reduce GHG; one way by promoting clean energy use for example biogas. Agricultural industry produces organic waste which contributes to global warming and climate change. In Karo District, mostly the people were farmers, either horticulture or fruit and produces massive organic waste. Biogas research was conducted in Karo District in May until July 2016 used 5 biodigesters. The purpose was to determine benefits of using biogas technology in order to reduct GHG emissions. The used design was Completely Randomized Design (CRD) with treatments: T1 (100% cow feces), T2 (75% cow feces + 25% horticultural waste), T3 (50% cow feces + 50% horticultural waste), T4 (25% cow feces + 75% horticultural waste) and T5 (100% horticultural waste). Parameter research were gas production, pH and temperature. The research result showed that T1 produced the highest methane ( P<0.05) compared to other treatments while T2 produced methane higher (P<0.05) compared to T4 or T5. There was no difference on methane production between T4 and T5. As conclusion application of biogas on agricultural waste supported local action plan for greenhouse gas emission reduction of North Sumatera Province 2010-2020. From horticultural waste, there were 2.1 × 106 ton CO2 eq in 2014 which were not calculated in RAD GRK (Regional Action Plan for Greenhouse Gas Emissions Reduction).

Lead recovery and glass microspheres synthesis from waste CRT funnel glasses through carbon thermal reduction enhanced acid leaching process.

PubMed

Mingfei, Xing; Yaping, Wang; Jun, Li; Hua, Xu

2016-03-15

In this study, a novel process for detoxification and reutilization of waste cathode ray tube (CRT) funnel glass was developed by carbon thermal reduction enhanced acid leaching process. The key to this process is removal of lead from the CRT funnel glass and synchronous preparation of glass microspheres. Carbon powder was used as an isolation agent and a reducing agent. Under the isolation of the carbon powder, the funnel glass powder was sintered into glass microspheres. In thermal reduction, PbO in the funnel glass was first reduced to elemental Pb by carbon monoxide and then located on the surface of glass microspheres which can be removed easily by acid leaching. Experimental results showed that temperature, carbon adding amount and holding time were the major parameters that controlled lead removal rate. The maximum lead removal rate was 94.80% and glass microspheres that measured 0.73-14.74μm were obtained successfully by setting the temperature, carbon adding amount and holding time at 1200°C, 10% and 30min, respectively. The prepared glass microspheres may be used as fillers in polymer materials and abrasive materials, among others. Accordingly, this study proposed a practical and economical process for detoxification and recycling of waste lead-containing glass. Copyright © 2015 Elsevier B.V. All rights reserved.

The Role of Microbial Iron Reduction in the Formation of Proterozoic Molar Tooth Structures

NASA Astrophysics Data System (ADS)

Hodgskiss, M. S. W.; Kunzmann, M.; Halverson, G. P.; Poirier, A.

2016-12-01

Molar tooth structures are poorly understood early diagenetic, microspar-filled voids in clay-rich carbonate sediments. They are a common structure in sedimentary successions dating from 2600-720 Ma, but do not occur in rocks older or younger. Despite being volumetrically significant in carbonate rocks of this age, their formation and disappearance are poorly understood. Here, we present iron isotope data, supported by carbon and oxygen isotopes, major and minor element concentrations, and total organic carbon and pyrite contents for samples from ten regions spanning 1870-635 Ma. The iron isotopic composition of molar tooth structures is almost always lighter (modal depletion of 2‰) than the carbonate or siliciclastic components in the host sediment, whereas carbon isotopes are indistinguishable. We interpret the isotopically light iron in molar tooth structures to have been produced by microbial iron reduction utilising Fe-oxyhydroxides and smectites. The microbial conversion of smectite to illite results in a volume reduction of clay minerals ( 30%), while locally increasing pore water alkalinity. Therefore, this biogeochemical process is a viable mechanism to produce voids and subsequently precipitate carbonate minerals. The disappearance of molar tooth structures is likely linked to a combination of a decrease in smectite abundance, a decline in the marine DIC reservoir, and increase in the concentration of O2 in shallow seawater in the mid-Neoproterozoic.

The carbon footprint of cataract surgery.

PubMed

Morris, D S; Wright, T; Somner, J E A; Connor, A

2013-04-01

Climate change is predicted to be one of the largest global health threats of the 21st century. Health care itself is a large contributor to carbon emissions. Determining the carbon footprint of specific health care activities such as cataract surgery allows the assessment of associated emissions and identifies opportunities for reduction. To assess the carbon footprint of a cataract pathway in a British teaching hospital. This was a component analysis study for one patient having first eye cataract surgery in the University Hospital of Wales, Cardiff. Activity data was collected from three sectors, building and energy use, travel and procurement. Published emissions factors were applied to this data to provide figures in carbon dioxide equivalents (CO2eq). The carbon footprint for one cataract operation was 181.8 kg CO2eq. On the basis that 2230 patients were treated for cataracts during 2011 in Cardiff, this has an associated carbon footprint of 405.4 tonnes CO2eq. Building and energy use was estimated to account for 36.1% of overall emissions, travel 10.1% and procurement 53.8%, with medical equipment accounting for the most emissions at 32.6%. This is the first published carbon footprint of cataract surgery and acts as a benchmark for other studies as well as identifying areas for emissions reduction. Within the procurement sector, dialogue with industry is important to reduce the overall carbon footprint. Sustainability should be considered when cataract pathways are designed as there is potential for reduction in all sectors with the possible side effects of saving costs and improving patient care.

The carbon footprint of cataract surgery

PubMed Central

Morris, D S; Wright, T; Somner, J E A; Connor, A

2013-01-01

Background Climate change is predicted to be one of the largest global health threats of the 21st century. Health care itself is a large contributor to carbon emissions. Determining the carbon footprint of specific health care activities such as cataract surgery allows the assessment of associated emissions and identifies opportunities for reduction. Aim To assess the carbon footprint of a cataract pathway in a British teaching hospital. Methods This was a component analysis study for one patient having first eye cataract surgery in the University Hospital of Wales, Cardiff. Activity data was collected from three sectors, building and energy use, travel and procurement. Published emissions factors were applied to this data to provide figures in carbon dioxide equivalents (CO2eq). Results The carbon footprint for one cataract operation was 181.8 kg CO2eq. On the basis that 2230 patients were treated for cataracts during 2011 in Cardiff, this has an associated carbon footprint of 405.4 tonnes CO2eq. Building and energy use was estimated to account for 36.1% of overall emissions, travel 10.1% and procurement 53.8%, with medical equipment accounting for the most emissions at 32.6%. Conclusions This is the first published carbon footprint of cataract surgery and acts as a benchmark for other studies as well as identifying areas for emissions reduction. Within the procurement sector, dialogue with industry is important to reduce the overall carbon footprint. Sustainability should be considered when cataract pathways are designed as there is potential for reduction in all sectors with the possible side effects of saving costs and improving patient care. PMID:23429413

The lithium storage performance of electrolytic-carbon from CO2

NASA Astrophysics Data System (ADS)

Tang, Juanjuan; Deng, Bowen; Xu, Fei; Xiao, Wei; Wang, Dihua

2017-02-01

Sustainable and affordable energy resources are urgently demanded to mitigate environmental issues. Herein, carbon materials, prepared by electrochemical reduction of greenhouse gas, CO2, in Li-Na-K carbonate molten salts (electrolytic-carbon), are tested as negative electrode materials for Li-ion batteries. Owing to the small particle size and suitable surface area, the electrolytic-carbon exhibits a high reversible capacity of 798 mAh g-1 (more than two times of graphites' theoretical capacity) at 50 mA g-1 and 266 mAh g-1 with a stable cyclability over 500 cycles at a current density up to 500 mA g-1, as well as remarkable rate performance. Furthermore, a comprehensively study was conducted to investigate the effects of electrolysis temperature and cell voltage on the electrochemical performance of the electrolytic-carbon. These results demonstrate a promising strategy to develop renewable high-performance carbon negative electrode materials for Li-ion batteries by molten salt capture and electrochemical reduction of CO2.

Thermo-mechanical evaluation of carbon-carbon primary structure for SSTO vehicles

NASA Astrophysics Data System (ADS)

Croop, Harold C.; Lowndes, Holland B.; Hahn, Steven E.; Barthel, Chris A.

1998-01-01

An advanced development program to demonstrate carbon-carbon composite structure for use as primary load carrying structure has entered the experimental validation phase. The component being evaluated is a wing torque box section for a single-stage-to-orbit (SSTO) vehicle. The validation or demonstration component features an advanced carbon-carbon design incorporating 3D woven graphite preforms, integral spars, oxidation inhibited matrix, chemical vapor deposited (CVD) oxidation protection coating, and ceramic matrix composite fasteners. The validation component represents the culmination of a four phase design and fabrication development effort. Extensive developmental testing was performed to verify material properties and integrity of basic design features before committing to fabrication of the full scale box. The wing box component is now being set up for testing in the Air Force Research Laboratory Structural Test Facility at Wright-Patterson Air Force Base, Ohio. One of the important developmental tests performed in support of the design and planned testing of the full scale box was the fabrication and test of a skin/spar trial subcomponent. The trial subcomponent incorporated critical features of the full scale wing box design. This paper discusses the results of the trial subcomponent test which served as a pathfinder for the upcoming full scale box test.

Awareness of Stress-Reduction Interventions on Work Attitudes: The Impact of Tenure and Staff Group in Australian Universities.

PubMed

Pignata, Silvia; Winefield, Anthony H; Provis, Chris; Boyd, Carolyn M

2016-01-01

This study explored the impact of staff group role and length of organizational tenure in the relationship between the awareness of stress interventions (termed intervention awareness: IA) and the work-related attitudinal outcomes of university employees. A two-wave longitudinal study of a sample of 869 employees from 13 universities completed a psychosocial work factors and health questionnaire. Hierarchical regression analyses examined the contribution of staff role and different lengths of organizational tenure with IA and employees' reports of job satisfaction, affective organizational commitment, trust in senior management, and perceived procedural justice. Employees' length of tenure affected the relation between IA and work attitudes, and there were also differences between academic and non-academic staff groups. For non-academic employees, IA predicted job satisfaction, affective organizational commitment, trust in senior management, and perceived procedural justice. However, for academics, IA only predicted job satisfaction and trust which identifies a need to increase the visibility of organizational interventions. Across the tenure groups, IA predicted: (1) perceived procedural justice for employees with five or less years of tenure; (2) job satisfaction for employees with 0-19 years of tenure; (3) trust in senior management for employees with 6-19 years of tenure; and (4) affective organizational commitment for employees with a tenure length of 6-10 years. Employees working at the university for an intermediate period had the most positive perceptions of their organization in terms of IA, job satisfaction, trust in senior management, and affective organizational commitment, whereas employees with 20-38 years of tenure had the least positive perceptions. Results suggest that employees in the middle of their careers report the most positive perceptions of their university. The findings highlight the need to attend to contextual issues in organizational stress and wellbeing interventions and suggest that management may need to implement new strategies and/or promote existing stress-management and reduction strategies to academics, and employees whom are either new to the university or those who have been working for the organization for longer periods of time to ensure that they are aware of organizational strategies to promote employee wellbeing and morale within their work environments.

Sulfur cycling in plays an important role in the development of Ocean Anoxic Events

NASA Astrophysics Data System (ADS)

Gomes, M. L.; Raven, M. R.; Fike, D. A.; Gill, B. C.; Johnston, D. T.

2017-12-01

Ocean Anoxic Events (OAEs) are major carbon cycle perturbations marked by enhanced organic carbon deposition in the marine realm and carbon isotope excursions in organic and inorganic carbon. Although not as severe as the "big five" mass extinctions, OAEs had dire consequences for marine ecosystems and thus influenced Mesozoic evolutionary patterns. Sulfur cycle reconstructions provide insight into the biogeochemical processes that played a role in the development of OAEs because the sulfur cycle is linked with the carbon and oxygen cycles. We present sulfur and oxygen isotope records from carbonate-associated sulfate from the Toarcian OAE that documents a positive sulfate-oxygen isotope excursion of +6‰, which is similar to the magnitude of the positive sulfur isotope excursion documented at the same site and other globally distributed sites. This high-resolution record allows us to explore temporal variability in the onset of the isotopic excursions: the onset of the positive sulfate-oxygen isotope excursion occurs at the same stratigraphic interval as the onset of the positive carbon isotope excursion and both precede the onset of the positive sulfate-sulfur isotope excursion. Because oxygen is rapidly recycled during oxidative sulfur cycling, changes in oxidative sulfur cycling affect oxygen isotope values of sulfate without impacting sulfur isotope values. Thus, the early onset of the sulfate-oxygen isotope excursion implies a change in oxidative sulfur cycling, which is likely due to a shoaling of the zone of sulfate reduction. We explore the consequences of sulfate reduction zone shoaling for organic carbon preservation. Specifically, the sulfurization of organic matter, which makes organic matter less susceptible to degradation, occurs more rapidly when the top of the zone of sulfate reduction is near or above the sediment water interface. Therefore, we suggest that the shoaling of the sulfate reduction zone locally changed pathways of oxidative sulfur cycling and enhanced organic carbon preservation. Given synchronous changes in similar, globally-distributed depositional environments, this impacted the global biogeochemical cycles of oxygen, carbon, and nutrients in ways that sustained decreased oxygen availability and influenced extinction patterns of marine organisms.

VISION-BASED MONITORING AND CONTROL OF CONSTRUCTION OPERATIONS CARBON FOOTPRINT

EPA Science Inventory

Automated and continuous carbon footprint monitoring of construction operations support the contractors and project managers with information required for assessment on carbon footprint of various construction operation alternatives. This can ultimately lead to reduction of...

Measuring the effect of fuel treatments on forest carbon using landscape risk analysis

NASA Astrophysics Data System (ADS)

Ager, A. A.; Finney, M. A.; McMahan, A.; Cathcart, J.

2010-12-01

Wildfire simulation modelling was used to examine whether fuel reduction treatments can potentially reduce future wildfire emissions and provide carbon benefits. In contrast to previous reports, the current study modelled landscape scale effects of fuel treatments on fire spread and intensity, and used a probabilistic framework to quantify wildfire effects on carbon pools to account for stochastic wildfire occurrence. The study area was a 68 474 ha watershed located on the Fremont-Winema National Forest in southeastern Oregon, USA. Fuel reduction treatments were simulated on 10% of the watershed (19% of federal forestland). We simulated 30 000 wildfires with random ignition locations under both treated and untreated landscapes to estimate the change in burn probability by flame length class resulting from the treatments. Carbon loss functions were then calculated with the Forest Vegetation Simulator for each stand in the study area to quantify change in carbon as a function of flame length. We then calculated the expected change in carbon from a random ignition and wildfire as the sum of the product of the carbon loss and the burn probabilities by flame length class. The expected carbon difference between the non-treatment and treatment scenarios was then calculated to quantify the effect of fuel treatments. Overall, the results show that the carbon loss from implementing fuel reduction treatments exceeded the expected carbon benefit associated with lowered burn probabilities and reduced fire severity on the treated landscape. Thus, fuel management activities resulted in an expected net loss of carbon immediately after treatment. However, the findings represent a point in time estimate (wildfire immediately after treatments), and a temporal analysis with a probabilistic framework used here is needed to model carbon dynamics over the life cycle of the fuel treatments. Of particular importance is the long-term balance between emissions from the decay of dead trees killed by fire and carbon sequestration by forest regeneration following wildfire.

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

NONE

The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report on their emissions of greenhouse gases, and on actions taken that have reduced or avoided emissions or sequestered carbon, to the Energy Information Administration (EIA). This, the second annual report of the Voluntary Reporting Program, describes information provided by the participating organizations on their aggregate emissions and emissions reductions, as well as their emissions reduction or avoidance projects, through 1995. This information has been compiled into a database that includes reports from 142 organizationsmore » and descriptions of 967 projects that either reduced greenhouse gas emissions or sequestered carbon. Fifty-one reporters also provided estimates of emissions, and emissions reductions achieved, for their entire organizations. The projects described actions taken to reduce emissions of carbon dioxide from energy production and use; to reduce methane and nitrous oxide emissions from energy use, waste management, and agricultural processes; to reduce emissions of halocarbons, such as CFCs and their replacements; and to increase carbon sequestration.« less

Aligned carbon nanotube with electro-catalytic activity for oxygen reduction reaction

DOEpatents

Liu, Di-Jia; Yang, Junbing; Wang, Xiaoping

2010-08-03

A catalyst for an electro-chemical oxygen reduction reaction (ORR) of a bundle of longitudinally aligned carbon nanotubes having a catalytically active transition metal incorporated longitudinally in said nanotubes. A method of making an electro-chemical catalyst for an oxygen reduction reaction (ORR) having a bundle of longitudinally aligned carbon nanotubes with a catalytically active transition metal incorporated throughout the nanotubes, where a substrate is in a first reaction zone, and a combination selected from one or more of a hydrocarbon and an organometallic compound containing an catalytically active transition metal and a nitrogen containing compound and an inert gas and a reducing gas is introduced into the first reaction zone which is maintained at a first reaction temperature for a time sufficient to vaporize material therein. The vaporized material is then introduced to a second reaction zone maintained at a second reaction temperature for a time sufficient to grow longitudinally aligned carbon nanotubes over the substrate with a catalytically active transition metal incorporated throughout the nanotubes.

A Healthy Reduction in Oil Dependence and Carbon Emissions

NASA Astrophysics Data System (ADS)

Higgins, P. A.; Higgins, M.

2003-12-01

Societal dependence on oil as an energy source for personal transportation leads to increasingly negative social consequences including climate change, air pollution, political and economic instability and habitat degradation. Our heavy reliance on the automobile for transportation, determined in part by urban sprawl, also contributes to the population's increasingly sedentary lifestyle and to a concomitant degradation in health. We have shown that widespread substitution of exercise, commensurate with previously recommended levels, through biking or walking instead of driving can substantially reduce oil consumption and carbon emissions. For example, if all individuals between the ages of 10 and 64 substituted one hour of cycling for driving the reduction in gasoline demand would be equivalent to the gas produced from 34.9 percent of current oil consumption. Relative to 1990 net US emissions, this constitutes a 10.9 percent reduction in carbon emissions. Therefore, substitution of exercise for driving could improve health, reduce carbon emissions and save more oil than even upper estimates of that contained in the Arctic National Wildlife Refuge.

Graphite Carbon-Supported Mo2C Nanocomposites by a Single-Step Solid State Reaction for Electrochemical Oxygen Reduction.

PubMed

Huang, K; Bi, K; Liang, C; Lin, S; Wang, W J; Yang, T Z; Liu, J; Zhang, R; Fan, D Y; Wang, Y G; Lei, M

2015-01-01

Novel graphite-molybdenum carbide nanocomposites (G-Mo2C) are synthesized by a typical solid state reaction with melamine and MoO3 as precursors under inert atmosphere. The characterization results indicate that G-Mo2C composites are composed of high crystallization and purity of Mo2C and few layers of graphite carbon. Mo2C nanoparticles with sizes ranging from 5 to 50 nm are uniformly supported by surrounding graphite layers. It is believed that Mo atom resulting from the reduction of MoO3 is beneficial to the immobilization of graphite carbon. Moreover, the electrocatalytic performances of G-Mo2C for ORR in alkaline medium are investigated by cyclic voltammetry (CV), rotating disk electrode (RDE) and chronoamperometry test with 3M methanol. The results show that G-Mo2C has a considerable catalytic activity and superior methanol tolerance performance for the oxygen reduction reaction (ORR) benefiting from the chemical interaction between the carbide nanoparticles and graphite carbon.

Tropical forest soil microbial communities couple iron and carbon biogeochemistry

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

Dubinsky, E.A.; Silver, W.L.; Firestone, M.K.

2009-10-15

We report that iron-reducing bacteria are primary mediators of anaerobic carbon oxidation in upland tropical soils spanning a rainfall gradient (3500 - 5000 mm yr-1) in northeast Puerto Rico. The abundant rainfall and high net primary productivity of these tropical forests provide optimal soil habitat for iron-reducing and iron-oxidizing bacteria. Spatially and temporally dynamic redox conditions make iron-transforming microbial communities central to the belowground carbon cycle in these wet tropical forests. The exceedingly high abundance of iron-reducing bacteria (up to 1.2 x 10{sup 9} cells per gram soil) indicated that they possess extensive metabolic capacity to catalyze the reduction ofmore » iron minerals. In soils from the higher rainfall sites, measured rates of ferric iron reduction could account for up to 44 % of organic carbon oxidation. Iron reducers appeared to compete with methanogens when labile carbon availability was limited. We found large numbers of bacteria that oxidize reduced iron at sites with high rates of iron reduction and large numbers of iron-reducers. the coexistence of large populations of ironreducing and iron-oxidizing bacteria is evidence for rapid iron cycling between its reduced and oxidized states, and suggests that mutualistic interactions among these bacteria ultimately fuel organic carbon oxidation and inhibit CH4 production in these upland tropical forests.« less

Early-diagenetic processes in marine mangrove sediments from Guadeloupe, French West Indies

NASA Astrophysics Data System (ADS)

Crémière, Antoine; Sebilo, Mathieu; Strauss, Harald; Gros, Olivier; Laverman, Anniet M.

2014-05-01

Sediment and pore-water geochemistry were investigated in two short sediment cores from the Manche-à-eau lagoon (Guadeloupe, French Caribbean island) surrounded by mangroves trees. These sediments present high total organic carbon content, ranging between 10 to 18 % wt, mainly originating from mangrove litter fall. Oxygen is depleted in the first few millimetres of the sediment indicating active organic carbon degradation. Seawater sulphate is entirely consumed within the first 20 cm of the sediments and total organic carbon content decreases with depth pointing out that early-diagenetic degradation of organic matter occurs with sulphate reduction. Sulphide produced as the results of sulphate reduction partly reacts with detrital iron-bearing minerals and precipitates as pyrite which is consistent with high amounts of sulphur in the sediments (4-5 % wt). The sulphur isotopic composition (δ34S) of both dissolved sulphate and sulphide in pore-water increases with depth displaying a large apparent isotopic fractionation (Δ34S) between both species of 65-80o as a result of bacterial sulphate reduction. Scanning electron microscopy investigation reveals that a part of the carbonate alkalinity produced either by organic matter oxidation or anaerobic methane oxidation leads to authigenic carbonates precipitation. These results provide straightforward evidence that carbon and sulphur biogeochemical cycles are intimately governed by sedimentary microbial activity.

Development of Flexi-Burn™ CFB Power Plant to Meet the Challenge of Climate Change

NASA Astrophysics Data System (ADS)

Hackt, Horst; Fant, Zhen; Seltzert, Andrew; Hotta, Arto; Erikssoni, Timo; Sippu, Ossi

Carbon-dioxide capture and storage (CCS) offers the potential for major reductions in carbon- dioxide emissions of fossil fuel-based power generation in the fairly short term, and oxyfuel combustion is one of the identified CCS technology options. Foster Wheeler (FW) is working on reduction of carbon-dioxide with its integrated Flexi-Burn™ CFB technology. The proven high efficiency circulating fluidized-bed (CFB) technology, when coupled with air separation units and carbon purification units, offers a solution for carbon dioxide reduction both in re-powering and in greenfield power plants. CFB technology has the advantages over pulverized coal technology of a more uniform furnace heat flux, increased fuel flexibility and offers the opportunity to further reduce carbon dioxide emissions by co-firing coal with bio-fuels. Development and design of an integrated Flexi-Bum™ CFB steam generator and balance of plant system was conducted for both air mode and oxyfuel mode. Through proper configuration and design, the same steam generator can be switched from air mode to oxyfuel mode without the need for unit shutdown for modifications. The Flexi-Burn™ CFB system incorporates features to maximize plant efficiency and power output when operating in the oxy-firing mode through firing more fuel in the same boiler.

Geochemical modeling of iron, sulfur, oxygen and carbon in a coastal plain aquifer

USGS Publications Warehouse

Brown, C.J.; Schoonen, M.A.A.; Candela, J.L.

2000-01-01

Fe(III) reduction in the Magothy aquifer of Long Island, NY, results in high dissolved-iron concentrations that degrade water quality. Geochemical modeling was used to constrain iron-related geochemical processes and redox zonation along a flow path. The observed increase in dissolved inorganic carbon is consistent with the oxidation of sedimentary organic matter coupled to the reduction of O2 and SO4/2- in the aerobic zone, and to the reduction of SO4/2- in the anaerobic zone; estimated rates of CO2 production through reduction of Fe(III) were relatively minor by comparison. The rates of CO2 production calculated from dissolved inorganic carbon mass transfer (2.55 x 10-4 to 48.6 x 10-4 mmol 1-1 yr-1) generally were comparable to the calculated rates of CO2 production by the combined reduction of O2, Fe(III) and SO4/2- (1.31 x 10-4 to 15 x 10-4 mmol 1-1 yr-1). The overall increase in SO4/2- concentrations along the flow path, together with the results of mass-balance calculations, and variations in ??34S values along the flow path indicate that SO4/2- loss through microbial reduction is exceeded by SO4/2- gain through diffusion from sediments and through the oxidation of FeS2. Geochemichal and microbial data on cores indicate that Fe(III) oxyhydroxide coatings on sediment grains in local, organic carbon- and SO4/2- -rich zones have localized SO4/2- -reducing zones in which the formation of iron disulfides been depleted by microbial reduction and resulted in decreases dissolved iron concentrations. These localized zones of SO4/2- reduction, which are important for assessing zones of low dissolved iron for water-supply development, could be overlooked by aquifer studies that rely only on groundwater data from well-water samples for geochemical modeling. (C) 2000 Elsevier Science B.V.Fe(III) reduction in the Magothy aquifer of Long Island, NY, results in high dissolved-iron concentrations that degrade water quality. Geochemical modeling was used to constrain iron-related geochemical processes and redox zonation along a flow path. The observed increase in dissolved inorganic carbon is consistent with the oxidation of sedimentary organic matter coupled to the reduction of O2 and SO42- in the aerobic zone, and to the reduction of SO42- in the anaerobic zone; estimated rates of CO2 production through reduction of Fe(III) were relatively minor by comparison. The rates of CO2 production calculated from dissolved inorganic carbon mass transfer (2.55??10-4 to 48.6??10-4mmol l-1yr-1) generally were comparable to the calculated rates of CO2 production by the combined reduction of O2, Fe(III) and SO42- (1.31??10-4 to 15??10-4mmol l-1yr-1). The overall increase in SO42- concentrations along the flow path, together with the results of mass-balance calculations, and variations in ??34S values along the flow path indicate that SO42- loss through microbial reduction is exceeded by SO42- gain through diffusion from sediments and through the oxidation of FeS2. Geochemical and microbial data on cores indicate that Fe(III) oxyhydroxide coatings on sediment grains in local, organic carbon- and SO42--rich zones have been depleted by microbial reduction and resulted in localized SO42--reducing zones in which the formation of iron disulfides decreases dissolved iron concentrations. These localized zones of SO42- reduction, which are important for assessing zones of low dissolved iron for water-supply development, could be overlooked by aquifer studies that rely only on groundwater data from well-water samples for geochemical modeling.

Delta-Flux: An eddy covariance network for a climate-smart Lower Mississippi Basin

USGS Publications Warehouse

Runkle, Benjamin R. K.; Rigby, James R.; Reba, Michele L.; Anapalli, Saseendran S.; Bhattacharjee, Joydeep; Krauss, Ken W.; Liang, Lu; Locke, Martin A.; Novick, Kimberly A.; Sui, Ruixiu; Suvočarev, Kosana; White, Paul M.

2017-01-01

Networks of remotely monitored research sites are increasingly the tool used to study regional agricultural impacts on carbon and water fluxes. However, key national networks such as the National Ecological Observatory Network and AmeriFlux lack contributions from the Lower Mississippi River Basin (LMRB), a highly productive agricultural area with opportunities for soil carbon sequestration through conservation practices. The authors describe the rationale to create the new Delta-Flux network, which will coordinate efforts to quantify carbon and water budgets at seventeen eddy covariance flux tower sites in the LMRB. The network structure will facilitate climate-smart management strategies based on production-scale and continuous measurements of carbon and water fluxes from the landscape to the atmosphere under different soil and water management conditions. The seventeen instrumented field sites are expected to monitor fluxes within the most characteristic landscapes of the target area: row-crop fields, pasture, grasslands, forests, and marshes. The network participants are committed to open collaboration and efficient regionalization of site-level findings to support sustainable agricultural and forestry management and conservation of natural resources.

Isotopic evidence for organic matter oxidation by manganese reduction in the formation of stratiform manganese carbonate ore

USGS Publications Warehouse

Okita, P.M.; Maynard, J.B.; Spiker, E. C.; Force, E.R.

1988-01-01

Unlike other marine-sedimentary manganese ore deposits, which are largely composed of manganese oxides, the primary ore at Molango (Hidalgo State, Mexico) is exclusively manganese carbonate (rhodochrosite, Mn-calcite, kutnahorite). Stable isotope studies of the carbonates from Molango provide critical new information relevant to the controversy over syngenetic and diagenetic models of stratiform manganese deposit formation. Negative ??13C values for carbonates from mineralized zones at Molango are strongly correlated with manganese content both on a whole rock scale and by mineral species. Whole rock ??13C data fall into three groups: high-grade ore = -16.4 to -11.5%.; manganese-rich, sub-ore-grade = -5.2 to 0%.; and unmineralized carbonates = 0 to +2.5%. (PDB). ??18O data show considerable overlap in values among the three groups: +4.8 to -2.8, -5.4 to -0.3%., and -7.4 to +6.2 (PDB), respectively. Isotopic data for individual co-existing minerals suggest a similar separation of ??13C values: ??13C values from calcite range from -1.1 to +0.7%. (PDB), whereas values from rhodochrosite are very negative, -12.9 to -5.5%., and values from kutnahorite or Mn-calcite are intermediate between calcite and rhodochrosite. 13C data are interpreted to indicate that calcite (i.e. unmineralized carbonate) formed from a normal marine carbon reservoir. However, 13C data for the manganese-bearing carbonates suggest a mixed seawater and organic source of carbon. The presence of only trace amounts of pyrite suggests sulfate reduction may have played a minor part in oxidizing organic matter. It is possible that manganese reduction was the predominant reaction that oxidized organic matter and that it released organic-derived CO2 to produce negative ??13C values and manganese carbonate mineralization. ?? 1988.

An overview of salt intake reduction efforts in the Gulf Cooperation Council countries.

PubMed

Alhamad, Nawal; Almalt, Elsayed; Alamir, Najeeba; Subhakaran, Monica

2015-06-01

Globally, morbidity and mortality from non-communicable diseases (NCDs) are increasing steadily and at an alarming rate. High blood pressure is a major risk factor for cardiovascular disease (CVD) and salt reduction is an effective measure to decrease mortality rates. In the Eastern Mediterranean region, current salt intake is high, with an average intake of >12 g per person per day. Reducing the intake of salt has been identified as a priority intervention to reduce NCDs. Countries of the Gulf Cooperation Council (GCC) are showing a willingness to comply with the World Health Organization (WHO) recommendations and an eagerness to reduce the burden of NCDs. However, they face some challenges, including lack of political commitment, lack of experience, and shortage of qualified human resources. Salt intake reduction efforts vary in the GCC region, from achieving 20% salt reduction in bread, to the very early stages of planning.

An overview of salt intake reduction efforts in the Gulf Cooperation Council countries

PubMed Central

Almalt, Elsayed; Alamir, Najeeba; Subhakaran, Monica

2015-01-01

Globally, morbidity and mortality from non-communicable diseases (NCDs) are increasing steadily and at an alarming rate. High blood pressure is a major risk factor for cardiovascular disease (CVD) and salt reduction is an effective measure to decrease mortality rates. In the Eastern Mediterranean region, current salt intake is high, with an average intake of >12 g per person per day. Reducing the intake of salt has been identified as a priority intervention to reduce NCDs. Countries of the Gulf Cooperation Council (GCC) are showing a willingness to comply with the World Health Organization (WHO) recommendations and an eagerness to reduce the burden of NCDs. However, they face some challenges, including lack of political commitment, lack of experience, and shortage of qualified human resources. Salt intake reduction efforts vary in the GCC region, from achieving 20% salt reduction in bread, to the very early stages of planning. PMID:26090327

Litter carbon stocks in forests of the US are markedly smaller than previously reported

Treesearch

Grant Domke; Charles Perry; Brian Walters; Christopher Woodall; Matthew Russell; James Smith

2015-01-01

Forest ecosystems are the largest terrestrial carbon sink on earth with more than half of their net primary production moving to the soil via the decomposition of litter biomass. Therefore, changes in the litter carbon pool have important implications for global carbon budgets and carbon emissions reduction targets and negotiations. Litter accounts for an estimated 5...

Impact of wastewater derived dissolved organic carbon on reduction, mobility, and bioavailability of As(V) and Cr(VI) in contaminated soils.

PubMed

Kunhikrishnan, Anitha; Choppala, Girish; Seshadri, Balaji; Wijesekara, Hasintha; Bolan, Nanthi S; Mbene, Kenneth; Kim, Won-Il

2017-01-15

In this work, the effects of various wastewater sources (storm water, sewage effluent, piggery effluent, and dairy effluent) on the reduction, and subsequent mobility and bioavailability of arsenate [As(V)] and chromate [Cr(VI)] were compared using both spiked and field contaminated soils. Wastewater addition to soil can increase the supply of carbon, nutrients, and stimulation of microorganisms which are considered to be important factors enhancing the reduction of metal(loid)s including As and Cr. The wastewater-induced mobility and bioavailability of As(V) and Cr(VI) were examined using leaching, earthworm, and soil microbial activity tests. The rate of reduction of As(V) was much less than that of Cr(VI) both in the presence and absence of wastewater addition. Wastewater addition increased the reduction of both As(V) and Cr(VI) compared to the control (Milli-Q water) and the effect was more pronounced in the case of Cr(VI). The leaching experiment indicated that Cr(VI) was more mobile than As(V). Wastewater addition increased the mobility and bioavailability of As(V), but had an opposite effect on Cr(VI). The difference in the mobility and bioavailability of Cr(VI) and As(V) between wastewater sources can be attributed to the difference in their dissolved organic carbon (DOC) content. The DOC provides carbon as an electron donor for the reduction of As(V) and Cr(VI) and also serves as a complexing agent thereby impacting their mobility and bioavailability. The DOC-induced reduction increased both the mobility and bioavailability of As, but it caused an opposite effect in the case of Cr. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evidence for iron-sulfate coupling in salt marsh sediments

NASA Astrophysics Data System (ADS)

Mills, Jennifer; Antler, Gilad; Turchyn, Alexandra

2014-05-01

Organic carbon burial in shallow marine sediments represents an important net sink in the global carbon cycle. Microbially mediated oxidation of organic matter in oxic, suboxic, and anoxic sediments however, prevents the ultimate burial of organic carbon and its removal from the surface of the planet. Although the subsurface transformations of organic carbon have been studied extensively, an enigmatic question remains: when organic matter is deposited, what determines whether it will be buried, reoxidized, or undergo methanogenesis? One hypothesis is that the sulfur cycle, due to the abundance of sulfate in many surface environments, dominates the subsurface oxidation or other fate of organic carbon. However, it has also been suggested that iron may in turn play a key role in determining the behavior of the sulfur cycle. To better understand the controls on these processes, we are using stable isotope and geochemical techniques to explore the microbially mediated oxidation of organic carbon in salt marsh sediments in North Norfolk, UK. In these sediments there is a high supply of organic carbon, iron, and sulfate (from diurnal tidal cycles). Thus these environments may provide insight into the nature of interactions between the carbon, iron, and sulfur cycles. A series of sampling missions was undertaken in the autumn and winter of 2013-2014. In subsurface fluid samples we observe very high ferrous iron concentrations (>1mM), indicative of extended regions of iron reduction (to over 30cm depth). Within these zones of iron reduction we would predict no sulfate reduction, and as expected δ34Ssulfate remains unchanged with depth. However, δ18Osulfate exhibits significant enrichments of up to 5 permil. This decoupling in the sulfur and oxygen isotopes of sulfate is suggestive of a sulfate recycling process in which sulfate is reduced to an intermediate sulfur species and subsequently reoxidized to sulfate. Taken together, these data suggest that microbial assemblages in these salt marsh sediments facilitate a cryptic cycling of sulfur, potentially mediated by iron species in the zone of iron reduction.

Global action to prevent war: a programme for government and grassroots efforts to stop war, genocide and other forms of deadly conflict.

PubMed

Dean, J; Forsberg, R C; Mendlovitz, S

2000-01-01

At the end of history's bloodiest century and the outset of a new millennium, we have an opportunity to fulfil one of humanity's oldest dreams: making the world largely free of war. Global changes make this goal achievable. Nuclear weapons have shown the folly of war. For the first time, there is no war and no immediate prospect of war among the main military powers. For the first time, many proven measures to prevent armed conflict, distilled in the crucible of this century's wars, are available. If systematically applied, these measures can sharply decrease the frequency and violence of war, genocide, and other forms of deadly conflict. To seize the opportunity, nations should adopt a comprehensive programme to reduce conventional armaments and armed conflict. This programme will complement and strengthen efforts to eliminate nuclear arms. To assure its ongoing worldwide implementation, the conventional reduction programme should be placed in a treaty framework. We propose a four-phased process, with three treaties, each lasting five to ten years, to lay the groundwork for the fourth treaty, which will establish a permanent international security system. The main objectives of the treaties are to achieve: 1. A verified commitment to provide full transparency on conventional armed forces and military spending, not to increase forces during negotiations on arms reductions, and to increase the resources allocated to multilateral conflict prevention and peacekeeping. 2. Substantial worldwide cuts in national armed forces and military spending and further strengthening of United Nations and regional peacekeeping and peace-enforcement capabilities. 3. A trial of a watershed commitment by participating nations, including the major powers, not to deploy their armed forces beyond national borders except in a multilateral action under UN or regional auspices. 4. A permanent transfer to the UN and regional security organizations of the authority and capability for armed intervention to prevent or end war, accompanied by further substantial cuts in national armed forces and increases in UN and regional forces. This programme offers many valuable features: a global framework for conventional forces that parallels the nuclear Non-Proliferation Treaty; a verified no-increase commitment for national armed forces based on full data exchange; a commitment to undertake prescribed confidence-building measures, including limits on force activities and deployments; a commitment to a specified plan for increased funding of UN and regional peacekeeping capabilities; a commitment to strengthen international legal institutions; and after a trial period, a lasting commitment by each participant not to unilaterally deploy its armed forces beyond its borders, but instead to give the responsibility for peacekeeping and peace enforcement to international institutions. This programme of phased steps to reduce armed forces and strengthen peacekeeping institutions will make war rare. It will foster the spread of zones of peace like those in North America and Western Europe where, after centuries of violence, international and civil war have given way to the peaceful settlement of disputes.

Interactive effects of frequent burning and timber harvesting on above ground carbon biomass in temperate eucalypt forests

NASA Astrophysics Data System (ADS)

Collins, Luke; Penman, Trent; Ximenes, Fabiano; Bradstock, Ross

2015-04-01

The sequestration of carbon has been identified as an important strategy to mitigate the effects of climate change. Fuel reduction burning and timber harvesting are two common co-occurring management practices within forests. Frequent burning and timber harvesting may alter forest carbon pools through the removal and redistribution of biomass and demographic and structural changes to tree communities. Synergistic and antagonistic interactions between frequent burning and harvesting are likely to occur, adding further complexity to the management of forest carbon stocks. Research aimed at understanding the interactive effects of frequent fire and timber harvesting on carbon biomass is lacking. This study utilised data from two long term (25 - 30 years) manipulative burning experiments conducted in southern Australia in temperate eucalypt forests dominated by resprouting canopy species. Specifically we examined the effect of fire frequency and harvesting on (i) total biomass of above ground carbon pools and (ii) demographic and structural characteristics of live trees. We also investigated some of the mechanisms driving these changes. Frequent burning reduced carbon biomass by up to 20% in the live tree carbon pool. Significant interactions occurred between fire and harvesting, whereby the reduction in biomass of trees >20 cm diameter breast height (DBH) was amplified by increased fire frequency. The biomass of trees <20 cm DBH increased with harvesting intensity in frequently burnt areas, but was unaffected by harvesting intensity in areas experiencing low fire frequency. Biomass of standing and fallen coarse woody debris was relatively unaffected by logging and fire frequency. Fire and harvesting significantly altered stand structure over the study period. Comparison of pre-treatment conditions to current conditions revealed that logged sites had a significantly greater increase in the number of small trees (<40 cm DBH) than unlogged sites. Logged sites showed a significant decrease in the number of large trees (>60 cm DBH) over the study period, while unlogged sites showed an increase. Frequently burnt logged sites showed the greatest reduction in large trees, presumably due to increased fire related mortality and collapse. Analysis of tree survival and growth data suggest that mortality rate is increased and growth rate reduced in frequently burnt areas compared to unburnt areas. Our findings suggest that future shifts towards more frequent fire (both prescribed fire and wildfire) could potentially lead to broad scale reductions in carbon sequestration in temperate forests and woodlands dominated by resprouting canopy species. Reductions in carbon sequestration associated with frequent burning will potentially be amplified in intensively harvested landscapes.

Decision-Making Processes during State Appropriation Cuts in Michigan Public Universities: How Administrators Respond to These Cuts a Case Study of State "A" University

ERIC Educational Resources Information Center

Almeshagbeh, Wasfi K.

2012-01-01

In principle and practice, Michigan's public universities are committed to the sustained improvement of educational and economic opportunities in the state. However, their place in the state's general fund budget makes them especially vulnerable to reductions, when resources are low. The remarkable impact that higher education has on every person…

High performance platinum single atom electrocatalyst for oxygen reduction reaction

NASA Astrophysics Data System (ADS)

Liu, Jing; Jiao, Menggai; Lu, Lanlu; Barkholtz, Heather M.; Li, Yuping; Wang, Ying; Jiang, Luhua; Wu, Zhijian; Liu, Di-Jia; Zhuang, Lin; Ma, Chao; Zeng, Jie; Zhang, Bingsen; Su, Dangsheng; Song, Ping; Xing, Wei; Xu, Weilin; Wang, Ying; Jiang, Zheng; Sun, Gongquan

2017-07-01

For the large-scale sustainable implementation of polymer electrolyte membrane fuel cells in vehicles, high-performance electrocatalysts with low platinum consumption are desirable for use as cathode material during the oxygen reduction reaction in fuel cells. Here we report a carbon black-supported cost-effective, efficient and durable platinum single-atom electrocatalyst with carbon monoxide/methanol tolerance for the cathodic oxygen reduction reaction. The acidic single-cell with such a catalyst as cathode delivers high performance, with power density up to 680 mW cm-2 at 80 °C with a low platinum loading of 0.09 mgPt cm-2, corresponding to a platinum utilization of 0.13 gPt kW-1 in the fuel cell. Good fuel cell durability is also observed. Theoretical calculations reveal that the main effective sites on such platinum single-atom electrocatalysts are single-pyridinic-nitrogen-atom-anchored single-platinum-atom centres, which are tolerant to carbon monoxide/methanol, but highly active for the oxygen reduction reaction.

High performance platinum single atom electrocatalyst for oxygen reduction reaction

PubMed Central

Liu, Jing; Jiao, Menggai; Lu, Lanlu; Barkholtz, Heather M.; Li, Yuping; Wang, Ying; Jiang, Luhua; Wu, Zhijian; Liu, Di-jia; Zhuang, Lin; Ma, Chao; Zeng, Jie; Zhang, Bingsen; Su, Dangsheng; Song, Ping; Xing, Wei; Xu, Weilin; Wang, Ying; Jiang, Zheng; Sun, Gongquan

2017-01-01

For the large-scale sustainable implementation of polymer electrolyte membrane fuel cells in vehicles, high-performance electrocatalysts with low platinum consumption are desirable for use as cathode material during the oxygen reduction reaction in fuel cells. Here we report a carbon black-supported cost-effective, efficient and durable platinum single-atom electrocatalyst with carbon monoxide/methanol tolerance for the cathodic oxygen reduction reaction. The acidic single-cell with such a catalyst as cathode delivers high performance, with power density up to 680 mW cm−2 at 80 °C with a low platinum loading of 0.09 mgPt cm−2, corresponding to a platinum utilization of 0.13 gPt kW−1 in the fuel cell. Good fuel cell durability is also observed. Theoretical calculations reveal that the main effective sites on such platinum single-atom electrocatalysts are single-pyridinic-nitrogen-atom-anchored single-platinum-atom centres, which are tolerant to carbon monoxide/methanol, but highly active for the oxygen reduction reaction. PMID:28737170

Hierarchically porous carbons with optimized nitrogen doping as highly active electrocatalysts for oxygen reduction

NASA Astrophysics Data System (ADS)

Liang, Hai-Wei; Zhuang, Xiaodong; Brüller, Sebastian; Feng, Xinliang; Müllen, Klaus

2014-09-01

Development of efficient, low-cost and stable electrocatalysts as the alternative to platinum for the oxygen reduction reaction is of significance for many important electrochemical devices, such as fuel cells, metal-air batteries and chlor-alkali electrolysers. Here we report a highly active nitrogen-doped, carbon-based, metal-free oxygen reduction reaction electrocatalyst, prepared by a hard-templating synthesis, for which nitrogen-enriched aromatic polymers and colloidal silica are used as precursor and template, respectively, followed by ammonia activation. Our protocol allows for the simultaneous optimization of both porous structures and surface functionalities of nitrogen-doped carbons. Accordingly, the prepared catalysts show the highest oxygen reduction reaction activity (half-wave potential of 0.85 V versus reversible hydrogen electrode with a low loading of 0.1 mg cm-2) in alkaline media among all reported metal-free catalysts. Significantly, when used for constructing the air electrode of zinc-air battery, our metal-free catalyst outperforms the state-of the-art platinum-based catalyst.

Monolithic carbon structures including suspended single nanowires and nanomeshes as a sensor platform

PubMed Central

2013-01-01

With the development of nanomaterial-based nanodevices, it became inevitable to develop cost-effective and simple nanofabrication technologies enabling the formation of nanomaterial assembly in a controllable manner. Herein, we present suspended monolithic carbon single nanowires and nanomeshes bridging two bulk carbon posts, fabricated in a designed manner using two successive UV exposure steps and a single pyrolysis step. The pyrolysis step is accompanied with a significant volume reduction, resulting in the shrinkage of micro-sized photoresist structures into nanoscale carbon structures. Even with the significant elongation of the suspended carbon nanowire induced by the volume reduction of the bulk carbon posts, the resultant tensional stress along the nanowire is not significant but grows along the wire thickness; this tensional stress gradient and the bent supports of the bridge-like carbon nanowire enhance structural robustness and alleviate the stiction problem that suspended nanostructures frequently experience. The feasibility of the suspended carbon nanostructures as a sensor platform was demonstrated by testing its electrochemical behavior, conductivity-temperature relationship, and hydrogen gas sensing capability. PMID:24256942

A review of carbon-based and non-carbon-based catalyst supports for the selective catalytic reduction of nitric oxide

PubMed Central

Anthonysamy, Shahreen Binti Izwan; Afandi, Syahidah Binti; Khavarian, Mehrnoush

2018-01-01

Various types of carbon-based and non-carbon-based catalyst supports for nitric oxide (NO) removal through selective catalytic reduction (SCR) with ammonia are examined in this review. A number of carbon-based materials, such as carbon nanotubes (CNTs), activated carbon (AC), and graphene (GR) and non-carbon-based materials, such as Zeolite Socony Mobil–5 (ZSM-5), TiO2, and Al2O3 supported materials, were identified as the most up-to-date and recently used catalysts for the removal of NO gas. The main focus of this review is the study of catalyst preparation methods, as this is highly correlated to the behaviour of NO removal. The general mechanisms involved in the system, the Langmuir–Hinshelwood or Eley–Riedeal mechanism, are also discussed. Characterisation analysis affecting the surface and chemical structure of the catalyst is also detailed in this work. Finally, a few major conclusions are drawn and future directions for work on the advancement of the SCR-NH3 catalyst are suggested. PMID:29600136

A review of carbon-based and non-carbon-based catalyst supports for the selective catalytic reduction of nitric oxide.

PubMed

Anthonysamy, Shahreen Binti Izwan; Afandi, Syahidah Binti; Khavarian, Mehrnoush; Mohamed, Abdul Rahman Bin

2018-01-01

Various types of carbon-based and non-carbon-based catalyst supports for nitric oxide (NO) removal through selective catalytic reduction (SCR) with ammonia are examined in this review. A number of carbon-based materials, such as carbon nanotubes (CNTs), activated carbon (AC), and graphene (GR) and non-carbon-based materials, such as Zeolite Socony Mobil-5 (ZSM-5), TiO 2 , and Al 2 O 3 supported materials, were identified as the most up-to-date and recently used catalysts for the removal of NO gas. The main focus of this review is the study of catalyst preparation methods, as this is highly correlated to the behaviour of NO removal. The general mechanisms involved in the system, the Langmuir-Hinshelwood or Eley-Riedeal mechanism, are also discussed. Characterisation analysis affecting the surface and chemical structure of the catalyst is also detailed in this work. Finally, a few major conclusions are drawn and future directions for work on the advancement of the SCR-NH 3 catalyst are suggested.

Highly uniform distribution of Pt nanoparticles on N-doped hollow carbon spheres with enhanced durability for oxygen reduction reaction

DOE PAGES

Shi, Qiurong; Zhu, Chengzhou; Engelhard, Mark H.; ...

2017-01-19

Here, carbon-supported Pt nanostructures currently exhibited great potential in polymer electrolyte membrane fuel cells. Nitrogen-doped hollow carbon spheres (NHCSs) with extra low density and high specific surface area are promising carbon support for loading Pt NPs. The doped heteroatom of nitrogen could not only contribute to the active activity for the oxygen reduction reaction (ORR), but also shows a strong interaction with Pt NPs for entrapping them from dissolution/migration. This synergetic effect/interaction resulted in the uniform dispersion and strong combination of the Pt NPs on the carbon support and thus play a significant role in hindering the degradation of themore » catalytic activities of Pt NPs. As expected, the as-obtained Pt/NHCSs displayed improved catalytic activity and superior durability toward ORR.« less

A polyacrylonitrile copolymer-silica template for three-dimensional hierarchical porous carbon as a Pt catalyst support for the oxygen reduction reaction.

PubMed

Liu, Minmin; Li, Jian; Cai, Chao; Zhou, Ziwei; Ling, Yun; Liu, Rui

2017-08-01

Herein, we report a novel route to construct a hierarchical three-dimensional porous carbon (3DC) through a copolymer-silica assembly. In the synthesis, silica acts as a hard template and leads to the formation of an interconnected 3D macropore, whereas styrene-co-acrylonitrile polymer has been used as both a carbon source and a soft template for micro- and meso-pores. The obtained 3DC materials possess a large surface area (∼550.5 m 2 g -1 ), which facilitates high dispersion of Pt nanoparticles on the carbon support. The 3DC-supported Pt electrocatalyst shows excellent performance in the oxygen reduction reaction (ORR). The easy processing ability along with the characteristics of hierarchical porosity offers a new strategy for the preparation of carbon nanomaterials for energy application.

Taxing pollution instead of labor: Is it a prudent CO[sub 2] reduction policy

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

Sanghi, A.K.; Joseph, A.L.

Any serious attempt to reduce carbon dioxide emissions will require reductions from all sectors of the economy. The authors believe that top-down approaches to a carbon tax will generate heavy excess revenues, thus causing administrative and equity problems. They suggest that a better approach, which was espoused by Vice President Gore, could come through a targeted trust fund approach.

The Effect of Hands-on '"Energy-Saving House" Learning Activities on Elementary School Students' Knowledge, Attitudes, and Behavior Regarding Energy Saving and Carbon-Emissions Reduction

ERIC Educational Resources Information Center

Lee, Lung-Sheng; Lin, Kuen-Yi; Guu, Yunn-Horng; Chang, Liang-Te; Lai, Chih-Chien

2013-01-01

Energy saving and carbon-emissions reduction (ESCER) are widely regarded as important issues for progress towards ensuring sustainable forms of economic development. This Taiwanese study focuses on the effects of a series of educational activities about ESCER on students' knowledge, attitudes and behavior. Sixty fifth-grade students from two…

Promotional Effect of Molten Carbonates on Proton Conductivity and Oxygen Reduction Reaction - an Experimental and Computational Study

NASA Astrophysics Data System (ADS)

Xiong, Xiaolei

Recent research of Solid oxide fuel cells (SOFCs) is aimed to lower the operating temperature to an intermediate temperature (IT) range of 500 to 700°C, while maintaining a proper performance. This Ph.D. research project investigates the promotional effects of alkaline carbonate eutectics on the proton conductivity of proton conducting electrolytes and cathodic ORR reactivity in SOFCs by both experimental and computational methods. The ionic conductivity of the MC-BZY composite above 500°C increases with the higher loading of MC. The sample exhibited nearly a factor of two higher conductivity in H2-containing atmosphere than in air. First-principles DFT modeling further investigated proton transfer at the interface of BaZrO 3 and molten carbonate. With the presence of carbonate ion, the energy barrier for proton migration becomes as low as 0.332 eV. The modeling indicates the reduction of energy barrier is resulted from the change of rate-determining step from proton transfer between oxygen atoms to proton rotation around oxygen atom. Infiltration of MC into porous cathode can reduce the polarization of resistance (Rp), i.e., enhance the oxygen reduction reaction (ORR) activity. The EIS analysis shows that MC has a beneficial effect on reducing Rp for different cathodes including Au, La0.8Sr 0.2MnO3-delta(LSM), La0.6Sr0.4Co 0.2Fe0.8O3-delta(LSCF) and La2NiO 4+delta (LNO). Specifically, the study on MC loading effect was carried out on LSCF cathode. It shows that a higher loading makes a greater reduction on Rp and the degree of reduction is the same from 500 to 600°C. As the loading increases to 1.4 wt%, the degree of Rp reduction tends to reach a limit. First-principles DFT modeling was further used to investigate the incorporation of oxygen into MC. The formation of CO 52- in molten carbonate was considered as a chemisorption of gas oxygen on the surface of MC infiltrated cathodes. After the formation of CO52-, it reacts with another CO3 2- to form two CO42-, which is a rate-limiting step on potential energy surface. After dissociation, oxygen atoms migrate in molten carbonate, which is energetically favor by intermolecular pathways. An O-O-O linkage is formed between carbonate ions, which facilitates the oxygen migration between carbonate ions.

The role of ecosystem-atmosphere interactions in simulated Amazonian precipitation decrease and forest dieback under global climate warming

NASA Astrophysics Data System (ADS)

Betts, R. A.; Cox, P. M.; Collins, M.; Harris, P. P.; Huntingford, C.; Jones, C. D.

A suite of simulations with the HadCM3LC coupled climate-carbon cycle model is used to examine the various forcings and feedbacks involved in the simulated precipitation decrease and forest dieback. Rising atmospheric CO2 is found to contribute 20% to the precipitation reduction through the physiological forcing of stomatal closure, with 80% of the reduction being seen when stomatal closure was excluded and only radiative forcing by CO2 was included. The forest dieback exerts two positive feedbacks on the precipitation reduction; a biogeophysical feedback through reduced forest cover suppressing local evaporative water recycling, and a biogeochemical feedback through the release of CO2 contributing to an accelerated global warming. The precipitation reduction is enhanced by 20% by the biogeophysical feedback, and 5% by the carbon cycle feedback from the forest dieback. This analysis helps to explain why the Amazonian precipitation reduction simulated by HadCM3LC is more extreme than that simulated in other GCMs; in the fully-coupled, climate-carbon cycle simulation, approximately half of the precipitation reduction in Amazonia is attributable to a combination of physiological forcing and biogeophysical and global carbon cycle feedbacks, which are generally not included in other GCM simulations of future climate change. The analysis also demonstrates the potential contribution of regional-scale climate and ecosystem change to uncertainties in global CO2 and climate change projections. Moreover, the importance of feedbacks suggests that a human-induced increase in forest vulnerability to climate change may have implications for regional and global scale climate sensitivity.

Cooperative Emissions Trading Game: International Permit Market Dominated by Buyers

PubMed Central

Honjo, Keita

2015-01-01

Rapid reduction of anthropogenic greenhouse gas emissions is required to mitigate disastrous impacts of climate change. The Kyoto Protocol introduced international emissions trading (IET) to accelerate the reduction of carbon dioxide (CO2) emissions. The IET controls CO2 emissions through the allocation of marketable emission permits to sovereign countries. The costs for acquiring additional permits provide buyers with an incentive to reduce their CO2 emissions. However, permit price has declined to a low level during the first commitment period (CP1). The downward trend in permit price is attributed to deficiencies of the Kyoto Protocol: weak compliance enforcement, the generous allocation of permits to transition economies (hot air), and the withdrawal of the US. These deficiencies created a buyer’s market dominated by price-making buyers. In this paper, I develop a coalitional game of the IET, and demonstrate that permit buyers have dominant bargaining power. In my model, called cooperative emissions trading (CET) game, a buyer purchases permits from sellers only if the buyer forms a coalition with the sellers. Permit price is determined by bargaining among the coalition members. I evaluated the demand-side and supply-side bargaining power (DBP and SBP) using Shapley value, and obtained the following results: (1) Permit price is given by the product of the buyer’s willingness-to-pay and the SBP (= 1 − DBP). (2) The DBP is greater than or equal to the SBP. These results indicate that buyers can suppress permit price to low levels through bargaining. The deficiencies of the Kyoto Protocol enhance the DBP, and contribute to the demand-side dominance in the international permit market. PMID:26244778

Climate Change Mitigation Challenge for Wood Utilization-The Case of Finland.

PubMed

Soimakallio, Sampo; Saikku, Laura; Valsta, Lauri; Pingoud, Kim

2016-05-17

The urgent need to mitigate climate change invokes both opportunities and challenges for forest biomass utilization. Fossil fuels can be substituted by using wood products in place of alternative materials and energy, but wood harvesting reduces forest carbon sink and processing of wood products requires material and energy inputs. We assessed the extended life cycle carbon emissions considering substitution impacts for various wood utilization scenarios over 100 years from 2010 onward for Finland. The scenarios were based on various but constant wood utilization structures reflecting current and anticipated mix of wood utilization activities. We applied stochastic simulation to deal with the uncertainty in a number of input variables required. According to our analysis, the wood utilization decrease net carbon emissions with a probability lower than 40% for each of the studied scenarios. Furthermore, large emission reductions were exceptionally unlikely. The uncertainty of the results were influenced clearly the most by the reduction in the forest carbon sink. There is a significant trade-off between avoiding emissions through fossil fuel substitution and reduction in forest carbon sink due to wood harvesting. This creates a major challenge for forest management practices and wood utilization activities in responding to ambitious climate change mitigation targets.

Surface-Satellite Measurements for Atmospheric Radiative Transfer (SMART)and Chemical, Optical and Microphysical Measurements of In-Situ Troposphere (COMMIT) Research Activities

NASA Technical Reports Server (NTRS)

Tsay, Si-Chee

2004-01-01

The GSFC SMART consists of a suite of remote sensing instruments, including many commercially available radiometers, spectrometer, interferometer, and three in-house developed inskuments: micro-pulse lidar (MPL), scanning microwave radiometer (SMiR), and sun-sky-surface photometer (S(sup 3)). SMART cover the spectral range from UV to microwave, and passive to active remote sensing. This is to enrich the EOS-like research activities (i.e., EOS validation, innovative investigations, and long-term local environmental observations). During past years, SMART has been deployed in many NASA supported field campaigns to collocate with satellite nadir overpass for intercomparisons, and for initializing model simulations. Built on the successful experience of SMART, we are currently developing a new ground-based in-situ sampling package, COMMIT, including measurements of trace gases (CO, SO2, NOx, and O3,) concentrations, fine/coarse particle sizers and chemical composition, single- and three-wavelength nephelometers, and surface meteorological probes. COMMIT is built for seeking a relationship between surface in-situ measurements and boundary layer characteristics. This is to enrich EOS-like research on removing boundary layer signal from the entire column from space observation - to deduce the stable (less variability) free-troposphere observations. The COMMIT will try its best to link the chemical, microphysical, and optical properties of the boundary layer with radiation. The next major activities for SMART-COMMIT are scheduled for 2004-2006 in BASE-ASIA and EAST-AIRE. The expected close collaboration of BASE-ASIA with various research projects in Asia (i.e., ABC in South Asia, led by Ramanathan et al.; EAST-AIRE in East Asia, led by Li et al.; and APEX in Northeast Asia, led by Nakajima et al.) will definitely provide a better understanding of the impact of the biomass burning and air pollutants on regional-to-global climate, hydrological and carbon cycles, and tropospheric chemistry in Asia.

Assessment of some cultural experimental methods to study the effects of antibiotics on microbial activities in a soil: An incubation study

PubMed Central

Molaei, Ali; Haghnia, Gholamhosain; Astaraei, Alireza; Rasouli-Sadaghiani, MirHassan; Teresa Ceccherini, Maria; Datta, Rahul

2017-01-01

Oxytetracycline (OTC) and sulfamethoxazole (SMX) are two of most widely used antibiotics in livestock and poultry industry. After consumption of antibiotics, a major portion of these compounds is excreted through the feces and urine of animals. Land application of antibiotic-treated animal wastes has caused increasing concern about their adverse effects on ecosystem health. In this regard, inconsistent results have been reported regarding the effects of antibiotics on soil microbial activities. This study was conducted based on the completely randomized design to the measure microbial biomass carbon, cumulative respiration and iron (III) reduction bioassays. Concentrations of OTC and SMX including 0, 1, 10, 25, 50, and 100 mg/kg were spiked in triplicate to a sandy loam soil and incubated for 21 days at 25°C. Results showed that the effects of OTC and SMX antibiotics on cumulative respiration and microbial biomass carbon were different. SMX antibiotic significantly affected soil microbial biomass carbon and cumulative respiration at different treatments compared to control with increasing incubation time. OTC antibiotic, on the other hand, negatively affected cumulative respiration compared to control treatment throughout the incubation period. Although OTC antibiotic positively affected microbial biomass carbon at day one of incubation, there was no clear trend in microbial biomass carbon between different treatments of this antibiotic after that time period. Nevertheless, sulfamethoxazole and oxytetracycline antibiotics had similar effects on iron (III) reduction such that they considerably affected iron (III) reduction at 1 and 10 mg/kg, and iron (III) reduction was completely inhibited at concentrations above 10 mg/kg. Hence, according to our results, microbial biomass carbon and cumulative respiration experiments are not able alone to exhibit the effect of antibiotics on soil microbial activity, but combination of these two experiments with iron (III) reduction test could well display the effects of sulfamethoxazole (SMX) and oxytetracycline (OTC) antibiotics on soil biochemical activities. PMID:28683144

Deep-Sea Carbonate Accumulation and Surface Ocean Saturation State in the Aftermath of the Cretaceous-Paleogene extinction

NASA Astrophysics Data System (ADS)

Pruss, S. B.; Higgins, J. A.; Bush, A. M.; Leckie, R. M.; Deeg, C.; Getzin, B. L.

2016-12-01

The role of the K-Pg extinction on biogeochemical cycling has been intensively studied in recent years. However, it remains unknown how extinctions in marine pelagic calcifiers impacted carbon cycling in the ocean. Low accumulation rates of microfossils in the aftermath of the extinction have been attributed to lowered production, which triggered a reduction in carbonate delivery to the seafloor. Interestingly, although microfossil abundance is lower and foraminifera are significantly smaller than in the latest Cretaceous, carbonate accumulated on the seafloor in the earliest Paleogene even in areas that should have been below the CCD. One such deep-water site in the South Pacific (U1370) was cored during IODP Expedition 329 in November 2010. We examined 16 samples from an anomalous carbonate layer provisionally assigned to lower Paleocene planktonic foraminiferal Zones P1a and P1b that preserves benthic and planktonic foraminifera. Carbon isotope values of the benthic species Nuttalies orealis range from 1.45 to 1.95‰ VPDB in the 16 samples. The planktonic species Parasubbotina pseudobulloides was only abundant enough for analysis in 4 samples, and these values range from 1.41 to 1.91‰ VPDB. We note, as others have, that no carbon isotope gradient existed between the benthic and planktonic foraminifera during the deposition of this carbonate layer, perhaps due to reduced primary production and/or export of organic carbon. The presence of this carbonate layer in the deep ocean and its preservation of a collapsed isotopic gradient are both consistent with a reduction in the surface-to-deep water gradient in carbonate saturation state during the unusual oceanographic conditions that followed the extinction. We speculate that this was associated with a sustained reduction in surface ocean saturation state with adverse consequences for neritic carbonate producers in the aftermath of the K-T extinction.

PRODUCTION OF URANIUM METAL BY CARBON REDUCTION

DOEpatents

Holden, R.B.; Powers, R.M.; Blaber, O.J.

1959-09-22

The preparation of uranium metal by the carbon reduction of an oxide of uranium is described. In a preferred embodiment of the invention a charge composed of carbon and uranium oxide is heated to a solid mass after which it is further heated under vacuum to a temperature of about 2000 deg C to produce a fused uranium metal. Slowly ccoling the fused mass produces a dendritic structure of uranium carbide in uranium metal. Reacting the solidified charge with deionized water hydrolyzes the uranium carbide to finely divide uranium dioxide which can be separated from the coarser uranium metal by ordinary filtration methods.

Maternal mortality in developing countries: challenges in scaling-up priority interventions.

PubMed

Prata, Ndola; Passano, Paige; Sreenivas, Amita; Gerdts, Caitlin Elisabeth

2010-03-01

Although maternal mortality is a significant global health issue, achievements in mortality decline to date have been inadequate. A review of the interventions targeted at maternal mortality reduction demonstrates that most developing countries face tremendous challenges in the implementation of these interventions, including the availability of unreliable data and the shortage in human and financial resources, as well as limited political commitment. Examples from developing countries, such as Sri Lanka, Malaysia and Honduras, demonstrate that maternal mortality will decline when appropriate strategies are in place. Such achievable strategies need to include redoubled commitments on the part of local, national and global political bodies, concrete investments in high-yield and cost-effective interventions and the delegation of some clinical tasks from higher-level healthcare providers to mid- or lower-level healthcare providers, as well as improved health-management information systems.

Chemoselective Radical Dehalogenation and C-C Bond Formation on Aryl Halide Substrates Using Organic Photoredox Catalysts.

PubMed

Poelma, Saemi O; Burnett, G Leslie; Discekici, Emre H; Mattson, Kaila M; Treat, Nicolas J; Luo, Yingdong; Hudson, Zachary M; Shankel, Shelby L; Clark, Paul G; Kramer, John W; Hawker, Craig J; Read de Alaniz, Javier

2016-08-19

Despite the number of methods available for dehalogenation and carbon-carbon bond formation using aryl halides, strategies that provide chemoselectivity for systems bearing multiple carbon-halogen bonds are still needed. Herein, we report the ability to tune the reduction potential of metal-free phenothiazine-based photoredox catalysts and demonstrate the application of these catalysts for chemoselective carbon-halogen bond activation to achieve C-C cross-coupling reactions as well as reductive dehalogenations. This procedure works both for conjugated polyhalides as well as unconjugated substrates. We further illustrate the usefulness of this protocol by intramolecular cyclization of a pyrrole substrate, an advanced building block for a family of natural products known to exhibit biological activity.

A high-performance mesoporous carbon supported nitrogen-doped carbon electrocatalyst for oxygen reduction reaction

NASA Astrophysics Data System (ADS)

Xu, Jingjing; Lu, Shiyao; Chen, Xu; Wang, Jianan; Zhang, Bo; Zhang, Xinyu; Xiao, Chunhui; Ding, Shujiang

2017-12-01

Investigating low-cost and highly active electrocatalysts for oxygen reduction reactions (ORR) is of crucial importance for energy conversion and storage devices. Herein, we design and prepare mesoporous carbon supported nitrogen-doped carbon by pyrolysis of polyaniline coated on CMK-3. This electrocatalyst exhibits excellent performance towards ORR in alkaline media. The optimized nitrogen-doped mesoporous electrocatalyst show an onset potential (E onset) of 0.95 V (versus reversible hydrogen electrode (RHE)) and half-wave potential (E 1/2) of 0.83 V (versus RHE) in 0.1 M KOH. Furthermore, the as-prepared catalyst presents superior durability and methanol tolerance compared to commercial Pt/C indicating its potential applications in fuel cells and metal-air batteries.

Influence of various carbon nano-forms as supports for Pt catalyst on proton exchange membrane fuel cell performance

NASA Astrophysics Data System (ADS)

Bharti, Abha; Cheruvally, Gouri

2017-08-01

In this study, we discuss the influence of various carbon supports for Pt on proton exchange membrane (PEM) fuel cell performance. Here, Pt supported on various carbon nano-forms [Pt/carbon black (Pt/CB), Pt/single-walled carbon nanotubes (Pt/SWCNT), Pt/multi-walled carbon nanotubes (Pt/MWCNT) and Pt/graphene (Pt/G)] are synthesized by a facile, single step, microwave-assisted, modified chemical reduction route. Their physical, chemical and electrochemical characteristics pertaining to oxygen reduction reaction (ORR) catalytic activity and stability in PEM fuel cell are studied in detail by various techniques and compared. The study shows that the different carbon supports does not significantly affect the Pt particle size during synthesis, but leads to different amount of defective sites in the carbon framework which influence both the availability of active metal nano-catalysts and metal-support interaction. In-situ electrochemical investigations reveal that the different carbon supports influence both ORR catalytic activity and stability of the catalyst. This is further corroborated by the demonstration of varying polarization characteristics on PEM fuel cell performance by different carbon supported Pt catalysts. This study reveals MWCNT as the most suitable carbon support for Pt catalyst, exhibiting high activity and stability for ORR in PEM fuel cell.

Short and long-term carbon balance of bioenergy electricity production fueled by forest treatments

Treesearch

Katherine C. Kelsey; Kallie L. Barnes; Michael G. Ryan; Jason C. Neff

2014-01-01

Forests store large amounts of carbon in forest biomass, and this carbon can be released to the atmosphere following forest disturbance or management. In the western US, forest fuel reduction treatments designed to reduce the risk of high severity wildfire can change forest carbon balance by removing carbon in the form of biomass, and by altering future potential...

Mbd3/NuRD controls lymphoid cell fate and inhibits tumorigenesis by repressing a B cell transcriptional program

PubMed Central

Hamey, Fiona K.; Errami, Youssef

2017-01-01

Differentiation of lineage-committed cells from multipotent progenitors requires the establishment of accessible chromatin at lineage-specific transcriptional enhancers and promoters, which is mediated by pioneer transcription factors that recruit activating chromatin remodeling complexes. Here we show that the Mbd3/nucleosome remodeling and deacetylation (NuRD) chromatin remodeling complex opposes this transcriptional pioneering during B cell programming of multipotent lymphoid progenitors by restricting chromatin accessibility at B cell enhancers and promoters. Mbd3/NuRD-deficient lymphoid progenitors therefore prematurely activate a B cell transcriptional program and are biased toward overproduction of pro–B cells at the expense of T cell progenitors. The striking reduction in early thymic T cell progenitors results in compensatory hyperproliferation of immature thymocytes and development of T cell lymphoma. Our results reveal that Mbd3/NuRD can regulate multilineage differentiation by constraining the activation of dormant lineage-specific enhancers and promoters. In this way, Mbd3/NuRD protects the multipotency of lymphoid progenitors, preventing B cell–programming transcription factors from prematurely enacting lineage commitment. Mbd3/NuRD therefore controls the fate of lymphoid progenitors, ensuring appropriate production of lineage-committed progeny and suppressing tumor formation. PMID:28899870

Europe's Shifting Response to HIV/AIDS: From Human Rights to Risk Management.

PubMed

Smith, Julia

2016-12-01

Despite a history of championing HIV/AIDS as a human rights issue, and a rhetorical commitment to health as a human right, European states and institutions have shifted from a rights-based response to a risk management approach to HIV/AIDS since the economic recession of 2008. An interdisciplinary perspective is applied to analyze health policy changes at the national, regional, and global levels by drawing on data from key informant interviews, and institutional and civil society documents. It is demonstrated that, in the context of austerity measures, member states such as the UK and Greece reduced commitments to rights associated with HIV/AIDS; at the regional level, the EU failed to develop rights-based approaches to address the vulnerabilities and health care needs of key populations affected by HIV/AIDS, particularly migrants and sex workers; and at the global level, the EU backtracked on commitments to global health and is prioritizing the intellectual property rights of pharmaceutical companies over the human rights of people living with HIV/AIDS. The focus within and from the EU is on containment, efficiency, and cost reduction. The rights of those most affected are no longer prioritized.

Europe’s Shifting Response to HIV/AIDS

PubMed Central

2016-01-01

Abstract Despite a history of championing HIV/AIDS as a human rights issue, and a rhetorical commitment to health as a human right, European states and institutions have shifted from a rights-based response to a risk management approach to HIV/AIDS since the economic recession of 2008. An interdisciplinary perspective is applied to analyze health policy changes at the national, regional, and global levels by drawing on data from key informant interviews, and institutional and civil society documents. It is demonstrated that, in the context of austerity measures, member states such as the UK and Greece reduced commitments to rights associated with HIV/AIDS; at the regional level, the EU failed to develop rights-based approaches to address the vulnerabilities and health care needs of key populations affected by HIV/AIDS, particularly migrants and sex workers; and at the global level, the EU backtracked on commitments to global health and is prioritizing the intellectual property rights of pharmaceutical companies over the human rights of people living with HIV/AIDS. The focus within and from the EU is on containment, efficiency, and cost reduction. The rights of those most affected are no longer prioritized. PMID:28559682

ACTIVATED CARBON PROCESS FOR TREATMENT OF WASTEWATERS CONTAINING HEXAVALENT CHROMIUM

EPA Science Inventory

The removal of hexavalent chromium, Cr(VI), from dilute aqueous solution by an activated carbon process has been investigated. Two removal mechanisms were observed; hexavalent chromium species were removed by adsorption onto the interior carbon surface and/or through reduction to...

Electron Transfer Strategies Regulate Carbonate Mineral and Micropore Formation.

PubMed

Zeng, Zhirui; Tice, Michael M

2018-01-01

Some microbial carbonates are robust biosignatures due to their distinct morphologies and compositions. However, whether carbonates induced by microbial iron reduction have such features is unknown. Iron-reducing bacteria use various strategies to transfer electrons to iron oxide minerals (e.g., membrane-bound enzymes, soluble electron shuttles, nanowires, as well as different mechanisms for moving over or attaching to mineral surfaces). This diversity has the potential to create mineral biosignatures through manipulating the microenvironments in which carbonate precipitation occurs. We used Shewanella oneidensis MR-1, Geothrix fermentans, and Geobacter metallireducens GS-15, representing three different strategies, to reduce solid ferric hydroxide in order to evaluate their influence on carbonate and micropore formation (micro-size porosity in mineral rocks). Our results indicate that electron transfer strategies determined the morphology (rhombohedral, spherical, or long-chained) of precipitated calcium-rich siderite by controlling the level of carbonate saturation and the location of carbonate formation. Remarkably, electron transfer strategies also produced distinctive cell-shaped micropores in both carbonate and hydroxide minerals, thus producing suites of features that could potentially serve as biosignatures recording information about the sizes, shapes, and physiologies of iron-reducing organisms. Key Words: Microbial iron reduction-Micropore-Electron transfer strategies-Microbial carbonate. Astrobiology 18, 28-36.

Navigation Performance of Global Navigation Satellite Systems in the Space Service Volume

NASA Technical Reports Server (NTRS)

Force, Dale A.

2013-01-01

GPS has been used for spacecraft navigation for many years center dot In support of this, the US has committed that future GPS satellites will continue to provide signals in the Space Service Volume center dot NASA is working with international agencies to obtain similar commitments from other providers center dot In support of this effort, I simulated multi-constellation navigation in the Space Service Volume In this presentation, I extend the work to examine the navigational benefits and drawbacks of the new constellations center dot A major benefit is the reduced geometric dilution of precision (GDOP). I show that there is a substantial reduction in GDOP by using all of the GNSS constellations center dot The increased number of GNSS satellites broadcasting does produce mutual interference, raising the noise floor. A near/far signal problem can also occur where a nearby satellite drowns out satellites that are far away. - In these simulations, no major effect was observed Typically, the use of multi-constellation GNSS navigation improves GDOP by a factor of two or more over GPS alone center dot In addition, at the higher altitudes, four satellite solutions can be obtained much more often center dot This show the value of having commitments to provide signals in the Space Service Volume Besides a commitment to provide a minimum signal in the Space Service Volume, detailed signal gain information is useful for mission planning center dot Knowledge of group and phase delay over the pattern would also reduce the navigational uncertainty

Carbon Balance and Contribution of Harvested Wood Products in China Based on the Production Approach of the Intergovernmental Panel on Climate Change.

PubMed

Ji, Chunyi; Cao, Wenbin; Chen, Yong; Yang, Hongqiang

2016-11-12

The carbon sequestration of harvested wood products (HWP) plays an important role in climate mitigation. Accounting the carbon contribution of national HWP carbon pools has been listed as one of the key topics for negotiation in the United Nations Framework Convention on Climate Change. On the basis of the revised Production Approach of the Intergovernmental Panel on Climate Change (2013) (IPCC), this study assessed the accounting of carbon stock and emissions from the HWP pool in China and then analyzed its balance and contribution to carbon mitigation from 1960 to 2014. Research results showed that the accumulated carbon stock in China's HWP carbon pool increased from 130 Teragrams Carbon (TgC) in 1960 to 705.6 TgC in 2014. The annual increment in the carbon stock rose from 3.2 TgC in 1960 to 45.2 TgC in 2014. The category of solid wood products accounted for approximately 95% of the annual amount. The reduction in carbon emissions was approximately twelve times that of the emissions from the HWP producing and processing stage during the last decade. Furthermore, the amount of carbon stock and emission reduction increased from 23 TgC in 1960 to 76.1 TgC in 2014. The annual contribution of HWP could compensate for approximately 2.9% of the national carbon dioxide emissions in China.

Carbon Balance and Contribution of Harvested Wood Products in China Based on the Production Approach of the Intergovernmental Panel on Climate Change

PubMed Central

Ji, Chunyi; Cao, Wenbin; Chen, Yong; Yang, Hongqiang

2016-01-01

The carbon sequestration of harvested wood products (HWP) plays an important role in climate mitigation. Accounting the carbon contribution of national HWP carbon pools has been listed as one of the key topics for negotiation in the United Nations Framework Convention on Climate Change. On the basis of the revised Production Approach of the Intergovernmental Panel on Climate Change (2013) (IPCC), this study assessed the accounting of carbon stock and emissions from the HWP pool in China and then analyzed its balance and contribution to carbon mitigation from 1960 to 2014. Research results showed that the accumulated carbon stock in China’s HWP carbon pool increased from 130 Teragrams Carbon (TgC) in 1960 to 705.6 TgC in 2014. The annual increment in the carbon stock rose from 3.2 TgC in 1960 to 45.2 TgC in 2014. The category of solid wood products accounted for approximately 95% of the annual amount. The reduction in carbon emissions was approximately twelve times that of the emissions from the HWP producing and processing stage during the last decade. Furthermore, the amount of carbon stock and emission reduction increased from 23 TgC in 1960 to 76.1 TgC in 2014. The annual contribution of HWP could compensate for approximately 2.9% of the national carbon dioxide emissions in China. PMID:27845760

CARBON DIOXIDE REDUCTION CONTACTORS IN SPACE VEHICLES AND OTHER ENCLOSED STRUCTURES,

DTIC Science & Technology

CONTROLLED ATMOSPHERES, CARBON DIOXIDE, REMOVAL, LIFE SUPPORT SYSTEMS, SPACE ENVIRONMENTS, CONFINED ENVIRONMENTS, OXYGEN CONSUMPTION, REGENERATION(ENGINEERING), CHEMISORPTION, MASS TRANSFER, FLUID MECHANICS, CENTRIFUGES .

Carbon footprint of telemedicine solutions--unexplored opportunity for reducing carbon emissions in the health sector.

PubMed

Holmner, Asa; Ebi, Kristie L; Lazuardi, Lutfan; Nilsson, Maria

2014-01-01

The healthcare sector is a significant contributor to global carbon emissions, in part due to extensive travelling by patients and health workers. To evaluate the potential of telemedicine services based on videoconferencing technology to reduce travelling and thus carbon emissions in the healthcare sector. A life cycle inventory was performed to evaluate the carbon reduction potential of telemedicine activities beyond a reduction in travel related emissions. The study included two rehabilitation units at Umeå University Hospital in Sweden. Carbon emissions generated during telemedicine appointments were compared with care-as-usual scenarios. Upper and lower bound emissions scenarios were created based on different teleconferencing solutions and thresholds for when telemedicine becomes favorable were estimated. Sensitivity analyses were performed to pinpoint the most important contributors to emissions for different set-ups and use cases. Replacing physical visits with telemedicine appointments resulted in a significant 40-70 times decrease in carbon emissions. Factors such as meeting duration, bandwidth and use rates influence emissions to various extents. According to the lower bound scenario, telemedicine becomes a greener choice at a distance of a few kilometers when the alternative is transport by car. Telemedicine is a potent carbon reduction strategy in the health sector. But to contribute significantly to climate change mitigation, a paradigm shift might be required where telemedicine is regarded as an essential component of ordinary health care activities and not only considered to be a service to the few who lack access to care due to geography, isolation or other constraints.

Drought impact on vegetation growth and mortality

NASA Astrophysics Data System (ADS)

Xu, C.; Wang, M.; Allen, C. D.; McDowell, N. G.; Middleton, R. S.

2017-12-01

Vegetation is a key regulator of the global carbon cycle via CO2 absorption through photosynthesis and subsequent growth; however, low water availability, heat stress, and disturbances associated with droughts could substantially reduce vegetation growth and increase vegetation mortality. As far as we know, there are few studies have assessed the drought impact on vegetation growth and mortality at regional and global scales. In this study, we analyzed 13 Earth System models (ESMs) to quantify the impact of drought on GPP and linked the remote-sensing based tree mortality to observed drought indices to assess the drought impact on tree mortality in continental US (CONUS). Our analysis of 13 Earth System models (ESMs) shows that the average global gross primary production (GPP) reduction per year associated with extreme droughts over years 2075-2099 is predicted to be 3-5 times larger than that over years 1850-1999. The annual drought-associated reduction in GPP over years 2075-2099 could be 52 and 74 % of annual fossil fuel carbon emission during years 2000-2007. Increasing drought impacts on GPP are driven primarily by the increasing drought frequency. The risks of drought-associated GPP reduction are particularly high for temperate and tropical regions. The consistent prediction of higher drought-associated reduction in NPP across 13 ESMs suggests increasing impacts of drought on the global carbon cycle with atmospheric warming. Our analysis of drought impact on tree mortality showed that drought-associated carbon loss accounts for 12% of forest carbon loss in CONUS for 2000-2014, which is about one-fifth of that resulting from timber harvesting and 1.35 % of average annual fossil fuel emissions in the U.S. for the same period. The carbon stock loss from natural disturbances for 2000-2014 is approximately 75% of the total carbon loss from anthropogenic disturbance (timber harvesting), suggesting that natural disturbances play a very important role on forest carbon loss from dead trees. Our results clearly demonstrate the importance of drought impact on forest carbon stocks at the continental level and will provide critical data for future model improvement to better predict the vegetation mortality under droughts.

Formation of carbonate pipes in the northern Okinawa Trough linked to strong sulfate exhaustion and iron supply

NASA Astrophysics Data System (ADS)

Peng, Xiaotong; Guo, Zixiao; Chen, Shun; Sun, Zhilei; Xu, Hengchao; Ta, Kaiwen; Zhang, Jianchao; Zhang, Lijuan; Li, Jiwei; Du, Mengran

2017-05-01

The microbial anaerobic oxidation of methane (AOM), a key biogeochemical process that consumes substantial amounts of methane produced in seafloor sediments, can lead to the formation of carbonate deposits at or beneath the sea floor. Although Fe oxide-driven AOM has been identified in cold seep sediments, the exact mode by which it may influence the formation of carbonate deposits remains poorly understood. Here, we characterize the morphology, petrology and geochemistry of a methane-derived Fe-rich carbonate pipe in the northern Okinawa Trough (OT). We detect abundant authigenic pyrites, as well as widespread trace Fe, within microbial mat-like carbonate veins in the pipe. The in situ δ34S values of these pyrites range from -3.9 to 31.6‰ (VCDT), suggesting a strong consumption of seawater sulfate by sulfate-driven AOM at the bottom of sulfate reduction zone. The positive δ56Fe values of pyrite and notable enrichment of Fe in the OT pipe concurrently indicate that the pyrites are primarily derived from Fe oxides in deep sediments. We propose that the Fe-rich carbonate pipe formed at the bottom of sulfate reduction zone, below which Fe-driven AOM, rather than Fe-oxide reduction coupled to organic matter degradation, might be responsible for the abundantly available Fe2+ in the fluids from which pyrites precipitated. The Fe-rich carbonate pipe described in this study probably represents the first fossil example of carbonate deposits linked to Fe-driven AOM. Because Fe-rich carbonate deposits have also been found at other cold seeps worldwide, we infer that similar processes may play an essential role in biogeochemical cycling of sub-seafloor methane and Fe at continental margins.

Experimental evidence for chemo-mechanical coupling during carbon mineralization in ultramafic rocks

NASA Astrophysics Data System (ADS)

Lisabeth, H. P.; Zhu, W.; Kelemen, P. B.; Ilgen, A.

2017-09-01

Storing carbon dioxide in the subsurface as carbonate minerals has the benefit of long-term stability and immobility. Ultramafic rock formations have been suggested as a potential reservoir for this type of storage due to the availability of cations to react with dissolved carbon dioxide and the fast reaction rates associated with minerals common in ultramafic formations; however, the rapid reactions have the potential to couple with the mechanical and hydraulic behavior of the rocks and little is known about the extent and mechanisms of this coupling. In this study, we argue that the dissolution of primary minerals and the precipitation of secondary minerals along pre-existing fractures in samples lead to reductions in both the apparent Young's modulus and shear strength of aggregates, accompanied by reduction in permeability. Hydrostatic and triaxial deformation experiments were run on dunite samples saturated with de-ionized water and carbon dioxide-rich solutions while stress, strain, permeability and pore fluid chemistry were monitored. Sample microstructures were examined after reaction and deformation using scanning electron microscopy (SEM). The results show that channelized dissolution and carbonate mineral precipitation in the samples saturated with carbon dioxide-rich solutions modify the structure of grain boundaries, leading to the observed reductions in stiffness, strength and permeability. A geochemical model was run to help interpret fluid chemical data, and we find that the apparent reaction rates in our experiments are faster than rates calculated from powder reactors, suggesting mechanically enhanced reaction rates. In conclusion, we find that chemo-mechanical coupling during carbon mineralization in dunites leads to substantial modification of mechanical and hydraulic behavior that needs to be accounted for in future modeling efforts of in situ carbon mineralization projects.

The potential of land management to decrease global warming from climate change

NASA Astrophysics Data System (ADS)

Mayer, A.; Hausfather, Z.; Jones, A. D.; Silver, W. L.

2016-12-01

Recent evidence suggests that negative emissions (i.e. sequestration) is critical to slow climate change (IPCC, 2013; Gasser et al, 2015). Agricultural (crop and grazing) lands have the potential to act as a significant carbon sink. These ecosystems cover a significant proportion of the global land surface, and are largely degraded with regard to soil carbon due to previous management practices (Bai et al, 2008). However, few studies have examined the required scale of land management interventions that would be required to make a significant contribution to a portfolio of efforts aimed at limiting anthropogenic influences on global mean temperature. To address this, we modelled the quantitative effect of a range of soil carbon sequestration rates on global temperature to 2100. Results showed that by assuming a baseline emissions scenario outlined in RCP 2.6, the sequestration of an additional 0.7 Pg C per year through improved agricultural land management practices would produce a reduction of 0.1 degrees C from predicted global temperatures by the year 2100. We also compiled previous estimates of global carbon sequestration potential of agricultural soils to compare with our theoretical prediction to determine whether carbon sequestration through existing land management practices has potential to significantly reduce global temperatures. Assuming long-term soil carbon uptake, the combined potential of agricultural land management-based mitigation approaches exceeded 0.25 degrees C warming reduction by the year 2100. However, results were highly sensitive to potential carbon saturation, defined as the maximum threshold for carbon storage in soil. Our results suggest that current land management technologies and available land area exist and could make a measureable impact on warming reduction. Results also highlighted potential carbon saturation as a key gap in knowledge.

Control of carbon balance in a silicon smelting furnace

DOEpatents

Dosaj, Vishu D.; Haines, Cathryn M.; May, James B.; Oleson, John D.

1992-12-29

The present invention is a process for the carbothermic reduction of silicon dioxide to form elemental silicon. Carbon balance of the process is assessed by measuring the amount of carbon monoxide evolved in offgas exiting the furnace. A ratio of the amount of carbon monoxide evolved and the amount of silicon dioxide added to the furnace is determined. Based on this ratio, the carbon balance of the furnace can be determined and carbon feed can be adjusted to maintain the furnace in carbon balance.

Geochemical modeling of iron, sulfur, oxygen and carbon in a coastal plain aquifer

NASA Astrophysics Data System (ADS)

Brown, C. J.; Schoonen, M. A. A.; Candela, J. L.

2000-11-01

Fe(III) reduction in the Magothy aquifer of Long Island, NY, results in high dissolved-iron concentrations that degrade water quality. Geochemical modeling was used to constrain iron-related geochemical processes and redox zonation along a flow path. The observed increase in dissolved inorganic carbon is consistent with the oxidation of sedimentary organic matter coupled to the reduction of O 2 and SO 42- in the aerobic zone, and to the reduction of SO 42- in the anaerobic zone; estimated rates of CO 2 production through reduction of Fe(III) were relatively minor by comparison. The rates of CO 2 production calculated from dissolved inorganic carbon mass transfer (2.55×10 -4 to 48.6×10 -4 mmol l -1 yr-1) generally were comparable to the calculated rates of CO 2 production by the combined reduction of O 2, Fe(III) and SO 42- (1.31×10 -4 to 15×10 -4 mmol l -1 yr-1). The overall increase in SO 42- concentrations along the flow path, together with the results of mass-balance calculations, and variations in δ34S values along the flow path indicate that SO 42- loss through microbial reduction is exceeded by SO 42- gain through diffusion from sediments and through the oxidation of FeS 2. Geochemical and microbial data on cores indicate that Fe(III) oxyhydroxide coatings on sediment grains in local, organic carbon- and SO 42--rich zones have been depleted by microbial reduction and resulted in localized SO 42--reducing zones in which the formation of iron disulfides decreases dissolved iron concentrations. These localized zones of SO 42- reduction, which are important for assessing zones of low dissolved iron for water-supply development, could be overlooked by aquifer studies that rely only on groundwater data from well-water samples for geochemical modeling.

Atmospheric carbon reduction by urban trees

Treesearch

David J. Nowak

1993-01-01

Trees, because they sequester atmospheric carbon through their growth process and conserve energy in urban areas, have been suggested as one means to combat increasing levels of atmospheric carbon. Analysis of the urban forest in Oakland, California (21% tree cover), reveals a tree carbon storage level of 11.0 metric tons/hectare. Trees in the area of the 1991 fire in...

The Effects of Earth Science Textbook Contents on High School Students' Knowledge of, Attitude toward, and Behavior of Energy Saving and Carbon Reduction

ERIC Educational Resources Information Center

Chao, Yu-Long; Chou, Ying-Chyi; Yen, Hsin-Yi; Chen, Shr-Jya

2017-01-01

As science textbooks are considered as one of the major source of climate change information of students, this study aims to examine the differences in energy saving and carbon reduction knowledge, attitude, and behavior between two groups of Taiwan's high school students using earth science textbooks of two different publishers. Some items of…

Electrochemical Interfaces and Electrode Processes.

DTIC Science & Technology

1984-08-15

reduction of 02 on such surfaces has been of special interest. Some of these complexes such as the iron tetrasulfonated phthalocyanines (TSPc) have high...high area carbon electrodes in porous carbon electrolyte structures (14,22,27). We have been successful in examining the Fe phthalocyanine and Co...Zagal, B. Z. Nikolic and R. R. Adzic, 1 May 1979. 50. A Mechanistic Study of 02 Reduction on Water Soluble Phthalocyanines Adsorbed on Graphite

Electrochemical reduction of carbon fluorine bond in 4-fluorobenzonitrile Mechanistic analysis employing Marcus Hush quadratic activation-driving force relation

NASA Astrophysics Data System (ADS)

Muthukrishnan, A.; Sangaranarayanan, M. V.

2007-10-01

The reduction of carbon-fluorine bond in 4-fluorobenzonitrile in acetonitrile as the solvent, is analyzed using convolution potential sweep voltammetry and the dependence of the transfer coefficient on potential is investigated within the framework of Marcus-Hush quadratic activation-driving force theory. The validity of stepwise mechanism is inferred from solvent reorganization energy estimates as well as bond length calculations using B3LYP/6-31g(d) method. A novel method of estimating the standard reduction potential of the 4-fluorobenzonitrile in acetonitrile is proposed.

Annealing of radiation damage in low resistivity silicon solar cells

NASA Technical Reports Server (NTRS)

Weinberg, I.; Swartz, C. K.

1980-01-01

The reduction of the temperatures required to restore cell performance after irradiation was investigated with emphasis on the annealing characteristics of two groups of cells containing different amounts of oxygen and carbon. Examination of defect behavior in irradiated boron doped silicon leads to the tentative conclusion that further reduction in annealing temperature could be achieved by decreasing the carbon concentration and either neutralizing the divacancy and/or minimizing its formation as a result of irradiation. A significant reduction in the temperature required to remove radiation induced degradation in 0.1 ohm centimeter silicon solar cells was achieved.

EU ambition to build the world's leading bioeconomy-Uncertain times demand innovative and sustainable solutions.

PubMed

Bell, John; Paula, Lino; Dodd, Thomas; Németh, Szilvia; Nanou, Christina; Mega, Voula; Campos, Paula

2018-01-25

This article outlines the current context and the development of the European Bioeconomy Strategy. It analyses the current situation, challenges and needs for EU action and concludes with the next steps that the European Commission will undertake to review and update the Bioeconomy Strategy. Bioeconomy offers great opportunities to realising a competitive, circular and sustainable economy with a sound industrial base that is less dependent on fossil carbon. A sustainable bioeconomy also contributes to climate change mitigation, with oceans, forests and soils being major carbon sinks and fostering negative CO 2 emissions. The EU has invested significantly in research and innovation in this field and the European Commission is committed to lead on European bioeconomy strategy. Copyright © 2017 Elsevier B.V. All rights reserved.

Bioturbation and Manganese Cycling in Hemipelagic Sediments

NASA Astrophysics Data System (ADS)

Aller, R. C.

1990-06-01

The activities of infaunal macrobenthos have major influences on the types, rates and distributions of diagenetic reactions involving manganese in relatively carbon-rich deep-sea and nearshore sediments. In some non-sulphidic hemipelagic deposits of the eastern equatorial Pacific (Panama Basin) biogenic reworking drives internal cycles of manganese, which can apparently account for up to ca. 100% of organic carbon oxidation and reduction of O2 supplied (diffusively) to the sea floor. Heterotrophic (carbon-based) manganese reduction is stimulated by simultaneous mixing of reactive organic matter and manganese oxide into suboxic-anoxic deposits. In sulphidic sediments, biogenic reworking must also enhance a lithotrophic pathway (sulphur-based) pathway of manganese reduction by promoting contact of manganese oxides and iron sulphides. Particle reworking dramatically alters the balance between aerobic and anaerobic decomposition pathways, promoting the utilization of O2 in the reoxidaton of reduced metabolites rather than direct oxidation of carbon. Irrigated burrows create microenvironments, which increase manganese reduction-oxidation and deplete Mn2+ from deeper pore waters. This may increase net Mn2+ production rates by removal of metabolites and potential co-precipitants with Mn2+. The occurrence and geometry of manganese oxide encrusted biogenic structures imply specific adaptations of infauna to manganese based microbial activity in hemipelagic sediments like the Panama Basin.

Reduction of CO2 diffuse emissions from the traditional ceramic industry by the addition of Si-Al raw material.

PubMed

González, I; Barba-Brioso, C; Campos, P; Romero, A; Galán, E

2016-09-15

The fabrication of ceramics can produce the emission of several gases, denominated exhaust gases, and also vapours resulting from firing processes, which usually contain metals and toxic substances affecting the environment and the health of workers. Especially harmful are the diffuse emissions of CO2, fluorine, chlorine and sulphur from the ceramics industry, which, in highly industrialized areas, can suppose an important emission focus of dangerous effects. Concerning CO2, factories that use carbonate-rich raw materials (>30% carbonates) can emit high concentrations of CO2 to the atmosphere. Thus, carbonate reduction or substitution with other raw materials would reduce the emissions. In this contribution, we propose the addition of Al-shales to the carbonated ceramic materials (marls) for CO2 emission reduction, also improving the quality of the products. The employed shales are inexpensive materials of large reserves in SW-Spain. The ceramic bodies prepared with the addition of selected Al-shale to marls in variable proportions resulted in a 40%-65% CO2 emission reduction. In addition, this research underlines at the same time that the use of a low-price raw material can also contribute to obtaining products with higher added value. Copyright © 2016 Elsevier Ltd. All rights reserved.

Understanding activity and selectivity of metal-nitrogen-doped carbon catalysts for electrochemical reduction of CO2.

PubMed

Ju, Wen; Bagger, Alexander; Hao, Guang-Ping; Varela, Ana Sofia; Sinev, Ilya; Bon, Volodymyr; Roldan Cuenya, Beatriz; Kaskel, Stefan; Rossmeisl, Jan; Strasser, Peter

2017-10-16

Direct electrochemical reduction of CO 2 to fuels and chemicals using renewable electricity has attracted significant attention partly due to the fundamental challenges related to reactivity and selectivity, and partly due to its importance for industrial CO 2 -consuming gas diffusion cathodes. Here, we present advances in the understanding of trends in the CO 2 to CO electrocatalysis of metal- and nitrogen-doped porous carbons containing catalytically active M-N x moieties (M = Mn, Fe, Co, Ni, Cu). We investigate their intrinsic catalytic reactivity, CO turnover frequencies, CO faradaic efficiencies and demonstrate that Fe-N-C and especially Ni-N-C catalysts rival Au- and Ag-based catalysts. We model the catalytically active M-N x moieties using density functional theory and correlate the theoretical binding energies with the experiments to give reactivity-selectivity descriptors. This gives an atomic-scale mechanistic understanding of potential-dependent CO and hydrocarbon selectivity from the M-N x moieties and it provides predictive guidelines for the rational design of selective carbon-based CO 2 reduction catalysts.Inexpensive and selective electrocatalysts for CO 2 reduction hold promise for sustainable fuel production. Here, the authors report N-coordinated, non-noble metal-doped porous carbons as efficient and selective electrocatalysts for CO 2 to CO conversion.

Protistan Predation Affects Trichloroethene Biodegradation in a Bedrock Aquifer▿

PubMed Central

Cunningham, Joseph J.; Kinner, Nancy E.; Lewis, Maureen

2009-01-01

Despite extensive research on the bottom-up force of resource availability (e.g., electron donors and acceptors), slow biodegradation rates and stalling at cis-dichloroethene (cDCE) and vinyl chloride continue to be observed in aquifers contaminated with trichloroethene (TCE). The objective of this research was to gauge the impact of the top-down force of protistan predation on TCE biodegradation in laboratory microcosms. When indigenous bacteria from an electron donor-limited TCE-contaminated bedrock aquifer were present, the indigenous protists inhibited reductive dechlorination altogether. The presence of protists during organic carbon-amended conditions caused the bacteria to elongate (length:width, ≥10:1), but reductive dechlorination was still inhibited. When a commercially available dechlorinating bacterial culture and an organic carbon amendment were added in he presence of protists, the elongated bacteria predominated and reductive dechlorination stalled at cDCE. When protists were removed under organic carbon-amended conditions, reductive dechlorination stalled at cDCE, whereas in the presence organic carbon and bacterial amendments, the total chlorinated ethene concentration decreased, indicating TCE was converted to ethene and/or CO2. The data suggested that indigenous protists grazed dechlorinators to extremely low levels, inhibiting dechlorination altogether. Hence, in situ bioremediation/bioaugmentation may not be successful in mineralizing TCE unless the top-down force of protistan predation is inhibited. PMID:19820148

Carbon-supported, selenium-modified ruthenium-molybdenum catalysts for oxygen reduction in acidic media.

PubMed

Guinel, Maxime J-F; Bonakdarpour, Arman; Wang, Biao; Babu, Panakkattu K; Ernst, Frank; Ramaswamy, Nagappan; Mukerjee, Sanjeev; Wieckowski, Andrzej

2009-07-20

The stability and oxygen reduction activity of two carbon-supported catalyst materials are reported. The catalysts, Se/Ru and Se/(Ru-Mo), were prepared by using a chemical reduction method. The catalyst nanoparticles were evenly dispersed onto globular amorphous carbon supports, and their average size was ca. 2.4 nm. Thermal treatment at 500 °C for 2 h in an inert argon atmosphere resulted in coarsening of the nanoparticles, and also in some decrease of their activity. A gradual reduction of activity was also observed for Se/Ru during potential-cycle experiments. However, the incorporation of small amounts of Mo into the Se/Ru catalysts considerably improved the stability of the catalyst against dissolution. The Mo-containing samples showed excellent oxygen reduction activities even after cycling the potential 1000 times between 0.7 and 0.9 V. Furthermore, they showed excellent fuel-cell behavior. The performance of the Se/Ru catalysts is greatly improved by the addition of small amounts of elemental Mo. Possible mechanisms responsible for the improvement of the activity are discussed. Copyright © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electrochemical Reduction of Protic Supercritical CO2 on Copper Electrodes.

PubMed

Melchaeva, Olga; Voyame, Patrick; Bassetto, Victor Costa; Prokein, Michael; Renner, Manfred; Weidner, Eckhard; Petermann, Marcus; Battistel, Alberto

2017-09-22

The electrochemical reduction of carbon dioxide is usually studied in aqueous solutions under ambient conditions. However, the main disadvantages of this method are high hydrogen evolution and low faradaic efficiencies of carbon-based products. Supercritical CO 2 (scCO 2 ) can be used as a solvent itself to suppresses hydrogen evolution and tune the carbon-based product yield; however, it has received little attention for this purpose. Therefore, the focus of this study was on the electrochemical reduction of scCO 2 . The conductivity of scCO 2 was increased through the addition of supporting electrolyte and a cosolvent (acetonitrile). Furthermore, the addition of protic solutions of different pH to scCO 2 was investigated. 1 m H 2 SO 4 , trifluoroethanol, H 2 O, KOH, and CsHCO 3 solutions were used to determine the effect on current density, faradaic efficiency, and selectivity of the scCO 2 reduction. The reduction of scCO 2 to methanol and ethanol are reported for the first time. However, methane and ethylene were not observed. Additionally, corrosion of the Cu electrode was noticed. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Physicochemical properties of metal-doped activated carbons and relationship with their performance in the removal of SO2 and NO.

PubMed

Gao, Xiang; Liu, Shaojun; Zhang, Yang; Luo, Zhongyang; Cen, Kefa

2011-04-15

Several metal-doped activated carbons (Fe, Co, Ni, V, Mn, Cu and Ce) were prepared and characterized. The results of N(2) adsorption-desorption, X-ray diffraction, and X-ray photoelectron spectroscopy indicated that some metals (Cu and Fe) were partly reduced by carbon during preparation. Activity tests for the removal of SO(2) and the selective catalytic reduction of NO with ammonia were carried out. Due to different physicochemical properties, different pathways for the SO(2) removal had been put out, i.e., catalytic oxidation, direct reaction and adsorption. This classification depended on the standard reduction potentials of metal redox pairs. Samples impregnated with V, Ce and Cu showed good activity for NO reduction by NH(3), which was also ascribed to the reduction potential values of metal redox pairs. Ce seemed to be a promising alternative to V due to the higher activity in NO reduction and the nontoxic property. A metal cation which could easily convert between the two valences seemed to be crucial to the good performance of both SO(2) and NO removal, just like V and Cu. Copyright © 2011 Elsevier B.V. All rights reserved.

CoMn2O4-supported functionalized carbon nanotube: efficient catalyst for oxygen reduction in microbial fuel cells

NASA Astrophysics Data System (ADS)

Zhu, Nengwu; Lu, Yu; Liu, Bowen; Zhang, Taiping; Huang, Jianjian; Shi, Chaohong; Wu, Pingxiao; Dang, Zhi; Wang, Ruixin

2017-10-01

Recently, the synthesis of nonprecious metal catalysts with low cost and high oxygen reduction reaction (ORR) efficiency is paid much attention in field of microbial fuel cells (MFCs). Transition metal oxides (AMn2O4, A = Co、Ni, and Zn) supported on carbon materials such as graphene and carbon nanotube exhibit stronger electroconductivity and more active sites comparing to bare AMn2O4. Herein, we demonstrate an easy operating Hummer's method to functionalize carbon nanotubes (CNTs) with poly (diallyldimethylammonium chloride) in order to achieve effective loading of CoMn2O4 nanoparticles, named CoMn2O4/PDDA-CNTs (CMODT). After solvothermal treatment, nanoscale CoMn2O4 particles ( 80 nm) were successfully attached on the noncovalent functionalized carbon nanotube. Results show that such composites possess an outstanding electrocatalytic activity towards ORR comparable to the commercial Pt/C catalyst in neutral media. Electrochemical detections as cyclic voltammogram (CV) and rotating ring-disk electrode tests (RRDE) showed that the potential of oxygen reduction peak of 30% CMODT was at - 0.3 V (vs Ag/AgCl), onset potential was at + 0.4 V. Among them, 30% CMODT composite appeared the best candidate of oxygen reduction via 3.9 electron transfer pathway. When 30% CMODT composite was utilized as cathode catalyst in air cathode MFC, the reactor obtained 1020 mW m-2 of the highest maximum power density and 0.781 V of open circuit voltage. The excellent activity and low cost (0.2 g-1) of the hybrid materials demonstrate the potential of transition metal oxide/carbon as effective cathode ORR catalyst for microbial fuel cells. [Figure not available: see fulltext.

Magnetic Carbon Supported Palladium Nanoparticles: An Efficient and Sustainable Catalyst for Hydrogenation Reactions

EPA Science Inventory

Magnetic carbon supported Pd catalyst has been synthesized via in situ generation of nanoferrites and incorporation of carbon from renewable cellulose via calcination; the catalyst can be used for the hydrogenation of alkenes and reduction of aryl nitro compounds.

Fungal mycelia show lag time before re-growth on endogenous carbon.

PubMed

Pollack, Judith K; Li, Zheng Jian; Marten, Mark R

2008-06-15

Nutrient starvation is a common occurrence for filamentous fungi. To better understand the effects of starvation, we used a parallel plate flow chamber to study individual fungal mycelia when subjected to a step change in glucose concentration. We report the presence of a finite "lag time" in starved mycelia during which they ceased to grow/extend while switching from growth on exogenous carbon to re-growth on endogenous carbon. This lag time precedes other morphological or physiological changes such as change in growth rate (50-70% reduction), vacuolation (up to 16%), and decreased hyphal diameter (almost 50% reduction). Data suggests that during lag time, vacuolar degradation produces sufficient endogenous carbon to support survival and restart hyphal extension. Lag time is inversely related to the size of the mycelium at the time of starvation, which suggests a critical flow of endogenous carbon to the apical tip. We present a mathematical model consistent with our experimental observations that relate lag time, area, and flow of endogenous carbon. (c) 2008 Wiley Periodicals, Inc.

Soft-Templating Synthesis of N-Doped Mesoporous Carbon Nanospheres for Enhanced Oxygen Reduction Reaction.

PubMed

Bayatsarmadi, Bita; Zheng, Yao; Jaroniec, Mietek; Qiao, Shi Zhang

2015-07-01

The development of ordered mesoporous carbon materials with controllable structures and improved physicochemical properties by doping heteroatoms such as nitrogen into the carbon framework has attracted a lot of attention, especially in relation to energy storage and conversion. Herein, a series of nitrogen-doped mesoporous carbon spheres (NMCs) was synthesized via a facile dual soft-templating procedure by tuning the nitrogen content and carbonization temperature. Various physical and (electro)chemical properties of the NMCs have been comprehensively investigated to pave the way for a feasible design of nitrogen-containing porous carbon materials. The optimized sample showed a favorable electrocatalytic activity as evidenced by a high kinetic current and positive onset potential for oxygen reduction reaction (ORR) due to its large surface area, high pore volume, good conductivity, and high nitrogen content, which make it a highly efficient ORR metal-free catalyst in alkaline solutions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis and photocatalytic CO2 reduction performance of Cu2O/Coal-based carbon nanoparticle composites

NASA Astrophysics Data System (ADS)

Dedong, Zhang; Maimaiti, Halidan; Awati, Abuduheiremu; Yisilamu, Gunisakezi; Fengchang, Sun; Ming, Wei

2018-05-01

The photocatalytic reduction of CO2 into hydrocarbons provides a promising approach to overcome the challenges of environmental crisis and energy shortage. Here we fabricated a cuprous oxide (Cu2O) based composite photocatalyst consisting of Cu2O/carbon nanoparticles (CNPs). To prepare the CNPs, coal samples from Wucaiwan, Xinjiang, China, were first treated with HNO3, followed by hydrogen peroxide (H2O2) oxidation to strip nanocrystalline carbon from coal. After linking with oxygen-containing group such as hydroxyl, coal-based CNPs with sp2 carbon structure and multilayer graphene lattice structure were synthesized. Subsequently, the CNPs were loaded onto the surface of Cu2O nanoparticles prepared by in-situ reduction of copper chloride (CuCl2·2H2O). The physical properties and chemical structure of the Cu2O/CNPs as well as photocatalytic activity of CO2/H2O reduction into CH3OH were measured. The results demonstrate that the Cu2O/CNPs are composed of spherical particles with diameter of 50 nm and mesoporous structure, which are suitable for CO2 adsorption. Under illumination of visible light, electron-hole pairs are generated in Cu2O. Thanks to the CNPs, the fast recombination of electron-hole pairs is suppressed. The energy gradient formed on the surface of Cu2O/CNPs facilitates the efficient separation of electron-hole pairs for CO2 reduction and H2O oxidation, leading to enhanced photocatalytic activity.

Decomposition of CO2 Emission Factors in Baoding

NASA Astrophysics Data System (ADS)

Li, Wei; Wang, xuyang; Zhang, Hongzhi

2018-01-01

Baoding, as one of the first “five provinces and eight cities” low carbon pilot cities, undertakes an important task and mission. The urgent task is to explore a peak route and emission reduction path suitable for Baoding’s own development, so as to provide reference for the construction of low-carbon pilot cities. At present, the carbon emissions of Baoding city and its subordinate districts and counties are not clear, and the carbon emissions, change trends and emission characteristics of various industries have not been systematically studied. This lead researcherscan not carry out further attribution analysis, the prediction of future emissions trends and put forward specific measures to reduce emissions are impossible.If the government can not accurately and comprehensively understand the problems faced in the construction and development of low-carbon cities, it is difficult to fundamentally put forward effective emission reduction policies and measures.

On the effect of the Fe(2+)/Fe(3+) redox couple on oxidation of carbon in hot H3PO4

NASA Technical Reports Server (NTRS)

Dhar, H. P.; Christner, L. G.; Kush, A. K.

1986-01-01

Oxidation studies of graphite:glassy carbon composites have been carried out at 1 and 4.7 atm. pressures in conc. H3PO4 in the presence and absence of iron ions. The concentration of the acid was varied over 85-100 wt pct, and of the iron ions over 30-300 ppm; the temperature varied over 190-210 C. Unlike the effect of Fe, which has been observed to increase the corrosion of carbon in sulphuric acid, the corrosion in phosphoric acid was observed to be slightly decreased or not at all affected. This result arises because of the catalytic reduction of the oxidized surface groups of carbon by Fe(2+) ions. The catalytic reduction is possible because under the experimental conditions the redox potential of the Fe(2+)/Fe(3+) couple is lower than the open-circuit voltage of carbon.

The onsite manufacture of propellant oxygen from lunar resources

NASA Technical Reports Server (NTRS)

Rosenberg, Sanders D.; Beegle, Robert L., Jr.; Guter, Gerald A.; Miller, Frederick E.; Rothenberg, Michael

1992-01-01

The Aerojet carbothermal process for the manufacture of oxygen from lunar materials has three essential steps: the reduction of silicate with methane to form carbon monoxide and hydrogen; the reduction of carbon monoxide with hydrogen to form methane and water; and the electrolysis of water to form hydrogen and oxygen. The reactions and the overall process are shown. It is shown with laboratory experimentation that the carbothermal process is feasible. Natural silicates can be reduced with carbon or methane. The important products are carbon monoxide, metal, and slag. The carbon monoxide can be completely reduced to form methane and water. The water can be electrolyzed to produce hydrogen and oxygen. A preliminary engineering study shows that the operation of plants using this process for the manufacture of propellant oxygen has a large economic advantage when the cost of the plant and its operation is compared to the cost of delivering oxygen from Earth.

Boron and oxygen-codoped porous carbon as efficient oxygen reduction catalysts

NASA Astrophysics Data System (ADS)

Lei, Zhidan; Chen, Hongbiao; Yang, Mei; Yang, Duanguang; Li, Huaming

2017-12-01

A low-cost boron- and oxygen-codoped porous carbon electrocatalyst towards oxygen reduction reaction (ORR) has been fabricated by a facile one-step pyrolysis approach, while a boron- and oxygen-rich polymer network was used as precursor. The boron- and oxygen-codoped carbon catalyst with high ORR electrocatalytic activity is comparable to that of Pt/C and is superior to that of catalysts doped solely with boron atoms or with oxygen atoms. Furthermore, the optimized boron- and oxygen-codoped carbon catalyst possesses excellent methanol tolerance and long-term durability in alkaline media. The high electrocatalytic activity of the dual-doped carbon catalysts can be attributed to the synergistic effects of high surface area, predominant mesostructure, abundant active oxygen-containing groups, and effective boron doping. The present results show that this boron- and oxygen-codoping strategy could be as a promising way for the preparation of highly efficient ORR catalysts.

Co@Co3O4 nanoparticle embedded nitrogen-doped carbon architectures as efficient bicatalysts for oxygen reduction and evolution reactions

NASA Astrophysics Data System (ADS)

Qi, Chunling; Zhang, Li; Xu, Guancheng; Sun, Zhipeng; Zhao, Aihua; Jia, Dianzeng

2018-01-01

The oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) play crucial roles in efficient energy conversion and storage solutions. Here, Co@Co3O4 nanoparticle embedded nitrogen-doped carbon architectures (denoted as Co@Co3O4/NCs) are prepared via a simple two-step and in situ approach by carbonization and subsequent oxidation of Co-MOF containing high contents of carbon and nitrogen. When evaluated as electrocatalyst towards both ORR and OER in a KOH electrolyte solution, the as-fabricated Co@Co3O4/NC-2 exhibits similar ORR catalytic activity to the commercial Pt/C catalyst, but superior stability and good methanol tolerance. Furthermore, the as-fabricated catalysts also show promising catalytic activity for OER. The effective catalytic activities originate from the synergistic effects between well wrapped Co@Co3O4 nanoparticles and nitrogen doped carbon structures.

Oxygen Generation from Carbon Dioxide for Advanced Life Support

NASA Technical Reports Server (NTRS)

Bishop, Sean; Duncan, Keith; Hagelin-Weaver, Helena; Neal, Luke; Sanchez, Jose; Paul, Heather L.; Wachsman, Eric

2007-01-01

The partial electrochemical reduction of carbon dioxide (CO2) using ceramic oxygen generators (COGs) is well known and widely studied. However, complete reduction of metabolically produced CO2 (into carbon and oxygen) has the potential of reducing oxygen storage weight for life support if the oxygen can be recovered. Recently, the University of Florida devel- oped novel ceramic oxygen generators employing a bilayer elec- trolyte of gadolinia-doped ceria and erbia-stabilized bismuth ox- ide (ESB) for NASA's future exploration of Mars. The results showed that oxygen could be reliably produced from CO2 at temperatures as low as 400 C. The strategy discussed here for advanced life support systems employs a catalytic layer com- bined with a COG cell so that CO2 is reduced all the way to solid carbon and oxygen without carbon buildup on the COG cell and subsequent deactivation.

Sulfate-dependent Anaerobic Oxidation of Methane as a Generation Mechanism for Calcite Cap Rock in Gulf Coast Salt Domes

NASA Astrophysics Data System (ADS)

Caesar, K. H.; Kyle, R.; Lyons, T. W.; Loyd, S. J.

2015-12-01

Gulf Coast salt domes, specifically their calcite cap rocks, have been widely recognized for their association with significant reserves of crude oil and natural gas. However, the specific microbial reactions that facilitate the precipitation of these cap rocks are still largely unknown. Insight into the mineralization mechanism(s) can be obtained from the specific geochemical signatures recorded in these structures. Gulf Coast cap rocks contain carbonate and sulfur minerals that exhibit variable carbon (d13C) and sulfur isotope (δ34S) signatures. Calcite d13C values are isotopically depleted and show a large range of values from -1 to -52‰, reflecting a mixture of various carbon sources including a substantial methane component. These depleted carbon isotope compositions combined with the presence of abundant sulfide minerals in cap rocks have led to interpretations that invoke microbial sulfate reduction as an important carbonate mineral-yielding process in salt dome environments. Sulfur isotope data from carbonate-associated sulfate (CAS: trace sulfate incorporated within the carbonate mineral crystal lattice) provide a more direct proxy for aqueous sulfate in salt dome systems and may provide a means to directly fingerprint ancient sulfate reduction. We find CAS sulfur isotope compositions (δ34SCAS) significantly greater than those of the precursor Jurassic sulfate-salt deposits (which exhibit δ34S values of ~ +15‰). This implies that cap rock carbonate generation occurred via microbial sulfate reduction under closed-system conditions. The co-occurrence of depleted carbonate d13C values (< ~30‰) and the enriched δ34SCAS values are evidence for sulfate-dependent anaerobic oxidation of methane (AOM). AOM, which has been shown to yield extensive seafloor carbonate authigenesis, is also potentially partly responsible for the carbonate minerals of the Gulf Coast calcite cap rocks through concomitant production of alkalinity. Collectively, these data shed new light on a potential hotspot of microbial activity in the deep biosphere.

Selective hydrogenation of phenol to cyclohexanone over Pd@CN (N-doped porous carbon): Role of catalyst reduction method

NASA Astrophysics Data System (ADS)

Hu, Shuo; Yang, Guangxin; Jiang, Hong; Liu, Yefei; Chen, Rizhi

2018-03-01

Selective phenol hydrogenation is a green and sustainable technology to produce cyclohexanone. The work focused on investigating the role of catalyst reduction method in the liquid-phase phenol hydrogenation to cyclohexanone over Pd@CN (N-doped porous carbon). A series of reduction methods including flowing hydrogen reduction, in-situ reaction reduction and liquid-phase reduction were designed and performed. The results highlighted that the reduction method significantly affected the catalytic performance of Pd@CN in the liquid-phase hydrogenation of phenol to cyclohexanone, and the liquid-phase reduction with the addition of appropriate amount of phenol was highly efficient to improve the catalytic activity of Pd@CN. The influence mechanism was explored by a series of characterizations. The results of TEM, XPS and CO chemisorption confirmed that the reduction method mainly affected the size, surface composition and dispersion of Pd in the CN material. The addition of phenol during the liquid-phase reduction could inhibit the aggregation of Pd NPs and promote the reduction of Pd (2+), and then improved the catalytic activity of Pd@CN. The work would aid the development of high-performance Pd@CN catalysts for selective phenol hydrogenation.

A Text Message Intervention with Adaptive Goal Support to Reduce Alcohol Consumption Among Non-Treatment-Seeking Young Adults: Non-Randomized Clinical Trial with Voluntary Length of Enrollment.

PubMed

Suffoletto, Brian; Chung, Tammy; Muench, Frederick; Monti, Peter; Clark, Duncan B

2018-02-16

Stand-alone text message-based interventions can reduce binge drinking episodes (≥4 drinks for women and ≥5 drinks for men) among nontreatment-seeking young adults, but may not be optimized. Adaptive text message support could enhance effectiveness by assisting context-specific goal setting and striving, but it remains unknown how to best integrate it into text message interventions. The objective of this study was to evaluate young adults' engagement with a text message intervention, Texting to Reduce Alcohol Consumption 2 (TRAC2), which focuses on reducing weekend alcohol consumption. TRAC2 incorporated preweekend drinking-limit goal-commitment ecological momentary assessments (EMA) tailored to past 2-week alcohol consumption, intraweekend goal reminders, self-efficacy EMA with support tailored to goal confidence, and maximum weekend alcohol consumption EMA with drinking limit goal feedback. We enrolled 38 nontreatment-seeking young adults (aged 18 to 25 years) who screened positive for hazardous drinking in an urban emergency department. Following a 2-week text message assessment-only run-in, subjects were given the opportunity to enroll in 4-week intervention blocks. We examined patterns of EMA responses and voluntary re-enrollment. We then examined how goal commitment and goal self-efficacy related to event-level alcohol consumption. Finally, we examined the association of length of TRAC2 exposure with alcohol-related outcomes from baseline to 3-month follow-up. Among a diverse sample of young adults (56% [28/50] female, 54% [27/50] black, 32% [12/50] college enrolled), response rates to EMA queries were, on average, 82% for the first 4-week intervention block, 75% for the second 4-week block, and 73% for the third 4-week block. In the first 4 weeks of the intervention, drinking limit goal commitment was made 68/71 times it was prompted (96%). The percentage of subjects being prompted to commit to a drinking limit goal above the binge threshold was 52% (15/29) in week 1 and decreased to 0% (0/15) by week 4. Subjects met their goal 130/146 of the times a goal was committed to (89.0%). There were lower rates of goal success when subjects reported lower confidence (score <4) in meeting the goal (76% [32/42 weekends]) compared with that when subjects reported high confidence (98% [56/57 weekends]; P=.001). There were reductions in alcohol consumption from baseline to 3 months, but reductions were not different by length of intervention exposure. Preliminary evidence suggests that nontreatment-seeking young adults will engage with a text message intervention incorporating self-regulation support features, resulting in high rates of weekend drinking limit goal commitment and goal success. ©Brian Suffoletto, Tammy Chung, Frederick Muench, Peter Monti, Duncan B Clark. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 16.02.2018.

Stability of carbon electrodes for aqueous lithium-air secondary batteries

NASA Astrophysics Data System (ADS)

Ohkuma, Hirokazu; Uechi, Ichiro; Matsui, Masaki; Takeda, Yasuo; Yamamoto, Osamu; Imanishi, Nobuyuki

2014-01-01

The air electrode performance of various carbon materials, such as Ketjen black (KB), acetylene black (AB and AB-S), Vulcan XC-72R (VX), and vapor grown carbon fiber (VGCF) with and without La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) catalyst were examined in an aqueous solution of saturated LiOH with 10 M LiCl in the current density range 0.2-2.0 mA cm-2. The best performance for oxygen reduction and evolution reactions was observed for the KB electrode, which has the highest surface area among the carbon materials examined. A steady over-potential of 0.2 V was obtained for the oxygen reduction reaction using the KB electrode without the catalyst, while the over-potential was 0.15 V for KB with the LSCF catalyst at 2.0 mA cm-2. The over-potentials for the oxygen evolution reaction were slightly higher than those for the oxygen reduction reaction, and gradually increased with the polarization period. Analysis of the gas in the cell after polarization above 0.4 V revealed the evolution of a small amount of CO during the oxygen evolution reaction by the decomposition of carbon in the electrode. The amount of CO evolved was significantly decreased by the addition of LSCF to the carbon electrode.

Carbon dots-decorated multiwalled carbon nanotubes nanocomposites as a high-performance electrochemical sensor for detection of H2O2 in living cells.

PubMed

Bai, Jing; Sun, Chunhe; Jiang, Xiue

2016-07-01

A novel enzyme-free hydrogen peroxide sensor composed of carbon dots (CDs) and multi-walled carbon nanotubes (MWCNTs) was prepared. It was found that the carbon dots-decorated multi-walled carbon nanotubes nanocomposites (CDs/MWCNTs) modified glassy carbon (GC) electrode (CDs/MWCNTs/GCE) exhibited a significant synergistic electrocatalytic activity towards hydrogen peroxide reduction as compared to carbon dots or multi-walled carbon nanotubes alone, and the CDs/MWCNTs/GCE has shown a low detection limit as well as excellent stability, selectivity, and reproducibility. These remarkable analytical advantages enable the practical application of CDs/MWCNTs/GCE for the real-time tracking of hydrogen peroxide (H2O2) released from human cervical cancer cells with satisfactory results. The enhanced electrochemical activity can be assigned to the edge plane-like defective sites and lattice oxygen in the CDs/MWCNTs nanocomposites due to the small amount of decoration of carbon dots on the multi-walled carbon nanotubes. Based on a facile preparation method and with good electrochemical properties, the CDs/MWCNTs nanocomposites represent a new class of carbon electrode for electrochemical sensor applications. Graphical Abstract CDs/MWCNTs exhibited good electrocatalytic activity and stability to H2O2 reduction and can be used for real-time detection of H2O2 released from living cells.

Height-related growth declines in ponderosa pine are not due to carbon limitation.

PubMed

Sala, Anna; Hoch, Günter

2009-01-01

Decreased gas exchange as trees grow tall has been proposed to explain age-related growth declines in trees. We examined changes of mobile carbon stores (starch, sugars and lipids) with tree height in ponderosa pine (Pinus ponderosa) at two sites differing in water availability, and tested the following hypotheses: (1) carbon supply does not become increasingly limited as trees grow tall; rather, the concentration of mobile carbon compounds increases with tree height reflecting greater reductions of carbon sink activities relative to carbon assimilation; and (2) increases of stored mobile carbon compounds with tree height are greater in drier sites. Height-related growth reductions were associated with significant increases of non-structural carbohydrates (NSC) and lipid concentrations in all tissues in the upper canopy and of NSC in the bole. Lipid concentrations in the bole decreased with tree height, but such decrease is not necessarily inconsistent with non-limiting carbon supply in tall trees. Furthermore, we found stronger increases of mobile carbon stores with tree height at the dry site relative to the moist site. Our results provide first direct evidence that carbon supply does not limit growth in tall trees and that decreases of water availability might negatively impact growth processes more than net-photosynthesis.

Thermodynamically controlled preservation of organic carbon in floodplains

NASA Astrophysics Data System (ADS)

Boye, Kristin; Noël, Vincent; Tfaily, Malak M.; Bone, Sharon E.; Williams, Kenneth H.; Bargar, John R.; Fendorf, Scott

2017-06-01

Organic matter decomposition in soils and terrestrial sediments has a prominent role in the global carbon cycle. Carbon stocks in anoxic environments, such as wetlands and the subsurface of floodplains, are large and presumed to decompose slowly. The degree of microbial respiration in anoxic environments is typically thought to depend on the energetics of available terminal electron acceptors such as nitrate or sulfate; microbes couple the reduction of these compounds to the oxidation of organic carbon. However, it is also possible that the energetics of the organic carbon itself can determine whether it is decomposed. Here we examined water-soluble organic carbon by Fourier-transform ion-cyclotron-resonance mass spectrometry to compare the chemical composition and average nominal oxidation state of carbon--a metric reflecting whether microbial oxidation of organic matter is thermodynamically favourable--in anoxic (sulfidic) and oxic (non-sulfidic) floodplain sediments. We observed distinct minima in the average nominal oxidation state of water-soluble carbon in sediments exhibiting anoxic, sulfate-reducing conditions, suggesting preservation of carbon compounds with nominal oxidation states below the threshold that makes microbial sulfate reduction thermodynamically favourable. We conclude that thermodynamic limitations constitute an important complement to other mechanisms of carbon preservation, such as enzymatic restrictions and mineral association, within anaerobic environments.

Quantifying carbon footprint reduction opportunities for U.S. households and communities.

PubMed

Jones, Christopher M; Kammen, Daniel M

2011-05-01

Carbon management is of increasing interest to individuals, households, and communities. In order to effectively assess and manage their climate impacts, individuals need information on the financial and greenhouse gas benefits of effective mitigation opportunities. We use consumption-based life cycle accounting techniques to quantify the carbon footprints of typical U.S. households in 28 cities for 6 household sizes and 12 income brackets. The model includes emissions embodied in transportation, energy, water, waste, food, goods, and services. We further quantify greenhouse gas and financial savings from 13 potential mitigation actions across all household types. The model suggests that the size and composition of carbon footprints vary dramatically between geographic regions and within regions based on basic demographic characteristics. Despite these differences, large cash-positive carbon footprint reductions are evident across all household types and locations; however, realizing this potential may require tailoring policies and programs to different population segments with very different carbon footprint profiles. The results of this model have been incorporated into an open access online carbon footprint management tool designed to enable behavior change at the household level through personalized feedback.

A hybrid method for provincial scale energy-related carbon emission allocation in China.

PubMed

Bai, Hongtao; Zhang, Yingxuan; Wang, Huizhi; Huang, Yanying; Xu, He

2014-01-01

Achievement of carbon emission reduction targets proposed by national governments relies on provincial/state allocations. In this study, a hybrid method for provincial energy-related carbon emissions allocation in China was developed to provide a good balance between production- and consumption-based approaches. In this method, provincial energy-related carbon emissions are decomposed into direct emissions of local activities other than thermal power generation and indirect emissions as a result of electricity consumption. Based on the carbon reduction efficiency principle, the responsibility for embodied emissions of provincial product transactions is assigned entirely to the production area. The responsibility for carbon generation during the production of thermal power is borne by the electricity consumption area, which ensures that different regions with resource endowments have rational development space. Empirical studies were conducted to examine the hybrid method and three indices, per capita GDP, resource endowment index and the proportion of energy-intensive industries, were screened to preliminarily interpret the differences among China's regional carbon emissions. Uncertainty analysis and a discussion of this method are also provided herein.

SWITCH-China: A Systems Approach to Decarbonizing China's Power System.

PubMed

He, Gang; Avrin, Anne-Perrine; Nelson, James H; Johnston, Josiah; Mileva, Ana; Tian, Jianwei; Kammen, Daniel M

2016-06-07

We present an integrated model, SWITCH-China, of the Chinese power sector with which to analyze the economic and technological implications of a medium to long-term decarbonization scenario while accounting for very-short-term renewable variability. On the basis of the model and assumptions used, we find that the announced 2030 carbon peak can be achieved with a carbon price of ∼$40/tCO2. Current trends in renewable energy price reductions alone are insufficient to replace coal; however, an 80% carbon emission reduction by 2050 is achievable in the Intergovernmental Panel on Climate Change Target Scenario with an optimal electricity mix in 2050 including nuclear (14%), wind (23%), solar (27%), hydro (6%), gas (1%), coal (3%), and carbon capture and sequestration coal energy (26%). The co-benefits of carbon-price strategy would offset 22% to 42% of the increased electricity costs if the true cost of coal and the social cost of carbon are incorporated. In such a scenario, aggressive attention to research and both technological and financial innovation mechanisms are crucial to enabling the transition at a reasonable cost, along with strong carbon policies.

DESC (Defense Electronics Supply Center) Total Quality Management Plan

DTIC Science & Technology

1989-04-01

Paoerwort Reduction Proodt(0704.01 ge. Washington. DC 20S03 4. TITLE AND SUBTITLE Api598 . FUNDING NUMBERS DESC Total Quality Management Master Plan...OF PAGES TQM (Total Quality Management ), Continuous Process Improvement,_________ cTainingManagement 16. PRICE CODE 17. SECURITY CLASSIFICATION 18... QUALITY MANAGEMENT As you read the DESC Total Quality Management Plan, I ask each of you to make a commitment to continuously strive for improvement

Joining Forces: Preparing to Fight Coalition Air War

DTIC Science & Technology

2013-06-01

as a communications officer, he graduated from pilot training and was assigned to Dyess AFB, Texas, as a B-1 pilot. Following an operational...the reality of the deficiencies themselves. The deficiencies may require a reduction in global commitments, which might increase security risks...the Air Power Challenges of the Post -Cold War Era (Maxwell AFB, AL: Air University Press, 2011), 28. 13 Benjamin S. Lambeth, The Transformation of